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Gikonyo NK, Hassanali A, Njagi PGN, Peter M, Midiwo JO. "Odor Composition of Preferred (Buffalo and Ox) and Nonpreferred (Waterbuck) Hosts of Some Savanna Tsetse Flies.". 2002. Abstracthttp://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/36947

A previous study on the feeding responses of tsetse flies, Glossina morsitans morsitans, implicated the existence of allomonal barriers, both volatile and nonvolatile, on the nonpreferred host, waterbuck, Kobus defassa. In the present study, electroantennogram-active compounds in odors from waterbuck were compared with those of two preferred hosts of tsetse flies, buffalo, Syncerus caffer, and ox, Bos indicus. Odors from the three bovids were trapped on activated charcoal and/or reverse-phase (octadecyl bonded) silica and analyzed with a gas chromatography-linked electroantennographic detector (GC-EAD) and, where possible, identified by using gas chromatography-linked mass spectrometry (GC-MS) and chromatographic comparisons with authentic samples. The GC-EAD profiles (with G. m. morsitans antennae) of the odors of the two preferred hosts were comparable, comprising medium-chain, saturated or unsaturated aldehydes and phenols, with buffalo emitting a few more EAG-active aldehydes. Waterbuck odor gave a richer profile, consisting of fewer aldehydes but more phenolic components and a series of 2-ketones (C8–C13) and δ-octalactone. This bovid also emits moderate amounts of C5–C9 straight-chain fatty acids, some of which were detected in buffalo and ox only in trace amounts. However, these did not elicit significant GC-EAD responses. Waterbuck profiles from the antennae of G. pallidipes showed broad similarity to those from G. m. morsitans, although the composition of aldehydes and ketones was somewhat different, indicating species-specific difference in the detection of host odors. Certain waterbuck-specific EAG-active components, particularly the 2-ketones and lactone, constitute a candidate allomonal blend in waterbuck odor.

Gikonyo J, Kibegwa F, Inyangala B. "Comparative assessment of hatching rates of African Catfish (Clarias gariepinus) eggs using Nile cabbage and kaka bans substrates." Livestock Research for Rural Development. 2017;29. Abstract
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Gikonyo C. "Rationalising the Use of the Anti-Money Laundering Regime in Tackling Somalia's Piracy for Ransoms." nternational Journal of Law, Crime and Justice. 2018:155-164.
Gikonyo NW, Ndiritu AW NG. "Transformational leadership practices of school principals: Does school ownership matter?". In: Second Annual International Interdisciplinary Conference. Catholic University of Eastern Africa (CUEA),; . CUEA, Kenya; 2013.
GikonyoNW NAW. "Inspiring a shared vision: getting all the teachers in the bandwagon." Journal of Education and Practice . 2014;5(5).
Gikungu M, Nyamasyo G, Muturi J, Mbugi JP, Mueke J, Jan Langerlof, Mungatu J. "Collembola Richness And Diversity Along A Gradient Of Land-use Intensity And Soil Abiotic Factors In Taita, Kenya.". 2009.Website
Gikunju M. Open Access Resources .; 2015.
Gikunju M, Nyamato-Kwenda R, Kwanya T. "A review of citizen librarianship in academic libraries in Kenya.". In: Digital Technologies for Information and Knowledge Management. Nairobi: Technical University of Kenya; 2019.
Gikunju JK, Mbaria JM, Mureithi W, Kyule MN, McDermott JJ, Maitho TE. "Water Fluoride in Molo Division of Nakuru District Kenya. ." Fluoride . 1995;28(1):17-20.
Gikunju M. Open Access Initiatives .; 2014.
Gilbert HF, O'Leary MH. "Modification of arginine and lysine in proteins with 2,4-pentanedione." Biochemistry. 1975;14(23):5194-9. Abstract

Primary amines react with 2,4-pentanedione at pH 6-9 to form enamines, N-alkyl-4-amino-3-penten-2-ones. The latter compounds readily regenerate the primary amine at low pH or on treatment with hydroxylamine. Guanidine and substituted guanidines react with 2,4-pentanedione to form N-substituted 2-amino-4,6-dimethylpyrimidines at a rate which is lower by at least a factor of 20 than the rate of reaction of 2,4-pentanedione with primary amines. Selective modification of lysine and arginine side chains in proteins can readily be achieved with 2,4-pentanedione. Modification of lysine is favored by reaction at pH 7 or for short reaction times at pH 9. Selective modification of arginine is achieved by reaction with 2,4-pentanedione for long times at pH 9, followed by treatment of the protein with hydroxylamine. The extent of modification of lysine and arginine side chains can readily be measured spectrophotometrically. Modification of lysozyme with 2,4-pentanedione at pH 7 results in modification of 3.8 lysine residues and less than 0.4 arginine residue in 24 hr. Modification of lysozyme with 2,4-pentanedione at pH 9 results in modification of 4 lysine residues and 4.5 arginine residues in 100 hr. Treatment of this modified protein with hydroxylamine regenerated the modified lysine residues but caused no change in the modified arginine residues. One arginine residue seems to be essential for the catalytic activity of the enzyme.

Gilbert-Kawai ET, Milledge JS, Grocott MPW, Martin DS. "King of the {Mountains}: {Tibetan} and {Sherpa} {Physiological} {Adaptations} for {Life} at {High} {Altitude}." Physiology. 2014;29:388-402. AbstractWebsite

Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation.

Gilbert-Kawai ET, Milledge JS, Grocott MPW, Martin DS. "King of the {Mountains}: {Tibetan} and {Sherpa} {Physiological} {Adaptations} for {Life} at {High} {Altitude}." Physiology. 2014;29:388-402. AbstractWebsite

Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation.

Gilbert-Kawai ET, Milledge JS, Grocott MPW, Martin DS. "King of the {Mountains}: {Tibetan} and {Sherpa} {Physiological} {Adaptations} for {Life} at {High} {Altitude}." Physiology. 2014;29:388-402. AbstractWebsite

Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation.

Gilbert-Kawai ET, Milledge JS, Grocott MPW, Martin DS. "King of the {Mountains}: {Tibetan} and {Sherpa} {Physiological} {Adaptations} for {Life} at {High} {Altitude}." Physiology. 2014;29:388-402. AbstractWebsite

Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation.

Gilbert-Kawai ET, Milledge JS, Grocott MPW, Martin DS. "King of the {Mountains}: {Tibetan} and {Sherpa} {Physiological} {Adaptations} for {Life} at {High} {Altitude}." Physiology. 2014;29:388-402. AbstractWebsite

Anecdotal evidence surrounding Tibetans' and Sherpas' exceptional tolerance to hypobaric hypoxia has been recorded since the beginning of high-altitude exploration. These populations have successfully lived and reproduced at high altitude for hundreds of generations with hypoxia as a constant evolutionary pressure. Consequently, they are likely to have undergone natural selection toward a genotype (and phenotype) tending to offer beneficial adaptation to sustained hypoxia. With the advent of translational human hypoxic research, in which genotype/phenotype studies of healthy individuals at high altitude may be of benefit to hypoxemic critically ill patients in a hospital setting, high-altitude natives may provide a valuable and intriguing model. The aim of this review is to provide a comprehensive summary of the scientific literature encompassing Tibetan and Sherpa physiological adaptations to a high-altitude residence. The review demonstrates the extent to which evolutionary pressure has refined the physiology of this high-altitude population. Furthermore, although many physiological differences between highlanders and lowlanders have been found, it also suggests many more potential avenues of investigation.

Gillespie SH, Cullen MM, Sam NE, Kanduma EG, McHugh TD. "Direct detection of heteroresistance in mycobacterium tuberculosis using molecular techniques.". 2006. Abstract
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Gillespie SH, Gosling RD, Uiso L, Sam NE, Kanduma EG, McHugh TD. "Early bactericidal activity of a moxifloxacin and isoniazid combination in smear-positive pulmonary tuberculosis." Journal of Antimicrobial Chemotherapy. 2005;56:1169-1171. Abstract
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Gina Ziervogel, Opere A. "Integrating Meteorological and Indigenous Knowledge-based Seasonal Climate Forecasts for the Agricultural Sector." CCAA learning paper, 1. 2010. Abstractintegrating_meteorological_and_indigenous_knowledge-based_seasonal_climate_forecasts_for_the_agricultural_sector.pdfIDRC Digital Library

Extreme climatic events, such as droughts and floods, as well as changes in the mean climate, have a direct
effect on crops and livestock and, thus, people’s livelihoods. Food security is at risk, particularly in sub-saharan Africa where local production remains largely rain-fed. Given that climate variability is likely to increase with increasing greenhouse gas emissions, it is more important than ever to understand how this variability can be managed to reduce the negative consequences.

The impact is already significant. In Malawi, for example, as a result of the 2002 drought, approximately 5 million people needed emergency food aid, which took a long time to be delivered. A similar situation occurred in Niger in 2004–2005 when approximately 2.5 million people — or a fifth of the population — was in need of food rations (UNDP 2007). In 2009, approximately 3.8 million people in Kenya required food aid because of the prolonged drought (FEWS Net 2010). In 2006, sub-Saharan Africa accounted for 13% of the world’s population and 25% of the undernourished people in the developing world (FAO 2006).

Gioto V, Wandiga S, Oludhe C. "Determinants of Household Food Security Status and Challenges of Building Resilience to Climate Variability and Change Posed by Drought in Tharaka …." Handbook of Climate Change Resilience. 2018;2(1):1-29. Abstractlink.springer.com

Climate change and variability pose momentous severe threats to agricultural development and consequently to economic growth and increased poverty levels. In reference, this paper examines the determinants of household food security status and assesses the challenges of building resilience to climate variability and change posed by drought in Tharaka Nithi, Kenya. The study coverage is Tharaka North and Tharaka South sub-counties which are semiarid and cover an area of 1,569 square kilometers (km2) with a total population of 158,023 people; this is about 65% of Tharaka Nithi County (Kenya). The sub-counties have three main livelihood zones (LZs). These are marginal mixed farming at 52%, mixed farming at 38%, and rain-fed cropping at 10%.

The area is exposed to climate change, aggravated by minimal adaptive capacity. Climate variability and climate change threaten food production leading to about 20–30% of the population being in poor and borderline food consumption score. The year 2017 describes one of the cyclical drought situations with low productivity and depleted range land conditions exposing approximately 30,000 persons in need of humanitarian assistance. This study reflects on challenges of building resilience to climate variability and change posed by drought using a transdisciplinary approach. The problems of the household food security status were poor rainfall performance, high temperatures, low livestock prices, high food prices, poor crop production, poor pasture and browse quality, and inadequate water for both domestic and livestock use. The solutions to the above-listed issues lie in the increased advocacy, rainwater harvesting structures, marketing linkages, timely early warning knowledge management, and eco-based farming practices. The study also found that there was a significant relationship between the household level of education, family size, household income, and household head age with food security. Findings of this study will form a platform for policy makers.

Keywords
Climate variability Climate change Tharaka Nithi Drought and resilience

Gioto V, Wandiga S, Oludhe C. "Climate Change Detection across All Livelihood Zones in Tharaka Nithi County." Journal of Meteorology and Related Sciences. 2016;9(2):14-24. Abstractresearchgate.net

Kenyan agriculture is largely rain-fed and principally dependent on rainfall. According to FEWS NET report for Kenya in August 2010 based on historical data from 70 rainfall stations and 17 air temperature stations to interpolate the long-rains precipitation and temperature trends for all of Kenya from 1960 to 2009 (Funk et al, 2010). The FEWS NET report indicate that in Kenya long-rains traditionally occur between March and June and short rains in October to December. The authors report that Kenya has experienced trend of decreasing rainfall and rising temperatures as Sudan. In Central Kenya, one of the country’s key agricultural regions, the area receiving adequate rainfall to support reliable rain-fed agriculture has declined by roughly 45 per cent since the mid 1970s (Funk et al, 2010). This study investigates change in temperature and rainfall pattern across all livelihood zones in Tharaka Nithi County. Data was collected for 39 years (1976 - 2015) period for the area of Study and in addition divisions were made to three non overlapping climate period of 30 years (1982 - 1991, 1992 – 200 and 2002 - 2012). The data were subjected to Gaussian kernel analysis, moments, regression, and non-parametric approaches based on Mann-Kendal statistics to justify any change in the average monthly and annually rain fall and temperature trend. The results indicate common change points and transitions from wet to dry (upward shift). The test indicates rainfall variation over the study area is significant (p= 0.05).The study recommended on the use of the information for Agricultural development and general socio-economic improvement.

Gisore P, Kaseje D, Were F, Ayuku D. "Motivational Interviewing Intervention on Health-Seeking Behaviors of Pregnant Women in Western Kenya." Applied Biobehavioral Research. 2014;19(2):144-156. Abstract

We studied the effect of using Motivational Interviewing Intervention (MII) on health facility delivery and newborn care practices among pregnant women receiving Care of the Mother and Newborn at Home (CNH) visits by Community Health Workers (CHWs). Near-Term women who had received at least oneCHWhome visit, were randomly assigned to one session of MII (intervention) or no MII (Control). Fifty five (55%) of intervention women, compared to 35% of control women delivered in health facilities. Intervention women also understood the need to breastfeed exclusively for 6 months better than controls (P = 0.000), and had a p-value of 0.07 for breastfeeding within one hour after birth. We concluded in the context of CHW Home visit program, adding may improve perinatal care.

Gisore JO, Khainga SO. "NEGATIVE PRESSURE WOUND THERAPY (NPWT) FOR THE MANAGEMENT OF LAPAROSTOMY WOUNDS: CASE SERIES." East Afr Med J. 2013;90(12):409-12. Abstract

Laparostomy or the open abdomen can be a lifesaving intervention in surgical emergencies for abdominal compartment syndrome, wound dehiscence, trauma and intra-abdominal sepsis. However, the open abdomen imposes a significant burden on nursing staff caring for these critically ill patients due to the large volume of exudate and fluid loss.To achieve mechanical containment of abdominal viscera and active removal of exudate, we used NPWT to manage five patients with complex intra-abdominal sepsis laparostomy wounds. It took between 12 to 28 days to achieve full granulation for secondary closure of the wounds. The series shows that in the management of laparostomy wounds, NPWT provides an easier way to manage the large volumes of exudates and reduces the frequency of dressings changes required with traditional wound dressings.

Gisore P, Kaseje D, Were F, Ayuku D. "Motivational Interviewing Intervention on Health-Seeking Behaviors of Pregnant Women in Western Kenya.". 2014;2(19):144-156. Abstractmotivational_interviewing_intervention_on.pdf

We studied the effect of using Motivational Interviewing Intervention (MII) on health facility delivery and newborn care practices among pregnant women receiving Care of the Mother and Newborn at Home (CNH) visits by Community Health Workers (CHWs). Near-Term women who had received at least one CHW home visit, were randomly assigned to one session of MII (intervention) or no MII (Control). Fifty five (55%) of intervention women, compared to 35% of control women delivered in health facilities. Intervention women also understood the need to breastfeed exclusively for 6 months better than controls (P = 0.000), and had a p-value of 0.07 for breastfeeding within one hour after birth. We concluded in the context of CHW Home visit program, adding may improve perinatal care.

GITAHI DRKIAMASTEPHEN. "Kiama S. G., D. Dreher M. Kok L. Cochand L. P. Nicod P. Gehr (2002) Live bacterial vectors for mucosal delivery of protective antigen. Targeting of mucosal dendritic cells.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2002. Abstract
Interleukin-18 (IL-18) plays an important role in innate and acquired immunity, in particular against intracellular pathogens. However, little is known about the microbial factors that trigger IL-18 secretion by dendritic cells (DCs). To determine the influence of bacterial virulence factors on the activation and release of IL-18, we infected human monocyte-derived DCs with virulence mutants of the facultative intracellular pathogen Salmonella typhimurium. Our results show that infection by S. typhimurium causes caspase-1-dependent activation of IL-18 and triggers the release of IL-18 in human DCs. The secretion of IL-18 by the DCs was closely correlated with the ability of the S. typhimurium strains to induce apoptosis. We demonstrate that activation and release of IL-18 are blocked by mutations in the Salmonella sipB gene, which encodes a virulence factor that activates caspase-1 to induce apoptosis. These findings indicate that the activation and release of IL-18 induced by bacterial virulence factors may represent one component of innate immunity against the intracellular bacteria.
GITAHI DRKIAMASTEPHEN. "Dreher D., Cochand L., Kok M., Pechere J. C., Kiama S.G., Gehr P., and L. P. Nicod (2000). Genetic background of Salmonella typhimurium vaccine strains has profound influence on infectivity and cytokine production in human dendritic cells. Schweiz. Med. W.". In: Fifth NFP37 Somatic Gene Therapy meeting. Elsevier; 2000. Abstract
Salmonella typhimurium (ST) can cause infection in man, and attenuated strains are under consideration as live vaccine vectors. However, little is known about the interaction of ST with human dendritic cells (DC). Here, we compared the consequences of exposure of human, monocyte-derived DC with different attenuated strains of ST. Infection was observed with all four strains tested (wild type, PhoP-, PhoPc, and AroA), but the PhoPc strain was by far the most efficient. Intracellular persistence of wild type and PhoP- was longer than that of PhoPc and AroA, both of which were largely eliminated within 24 h. Most DC survived infection by the attenuated strains, although apoptosis was observed in a fraction of the exposed cells. All strains induced DC maturation, independent from the extent of infection. Although all strains stimulated secretion of TNF-alpha and IL-12 strongly, PhoPc induced significantly less IL-10 than the other three strains and as much as 10 times less IL-10 than heat-killed PhoPc, suggesting that this mutant suppressed the secretion of IL-10 by the DC. These data indicate that infectivity, bacterial elimination, and cytokine secretion in human DC are controlled by the genetic background of ST.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N., Weyrauch, K. D. and P.Gehr (1998). A scanning electron microscope study of the luminal surface specialisations in the blood vessels of the pecten oculi in a diurnal bird, the black kite (Milvus migrans). Anna.". In: Presented at the . Elsevier; 1998. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Obregon C., Dreher, D., Kok M., Cochand L., Kiama S. G., and L. P Nicod (2003). Human alveolar macrophages infected by virulent bacterial expressing SipB are a major source of Active interleukin-18. Infection and Immunity 71: 4382-4388.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2003. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (2001). Human dendritic cells. .". In: Presented at the Department of Human Anatomy, University of Nairobi, Kenya on 22nd August 2001. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Nicod L. P., and P. Gehr (1999). Stereological assessment of phagocytosis by dendritic cells.". In: Presented at the 31st Curriculum Vitae Kiama S G, December 2006 Annual meeting of USGEB held in Basel Switzerland on October 14-15,1999. Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., J. N. Maina, K. D. Weyrauch, D. K. Mwangi (2004). The morphology of the pecten oculi of the ostrich, Struthio camelus.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2004. Abstract
The pecten oculi is a structure peculiar to the avian eye. Three morphological types of pecten oculi are recognized: conical type, vaned type and pleated type. The pleated type has been well studied. However, there exists only scanty data on the morphology of the latter two types of pectens. The structure of the vaned type of pecten of the ostrich, Struthio camelus was investigated with light and electron microscope. The pecten of this species consists of a vertical primary lamella that arises from the optic disc and supports 16-19 laterally located secondary lamellae, which run from the base and confluence at the apex. Some of the secondary lamellae give rise to 2 or 3 tertiary lamellae. The lamellae provide a wide surface, which supports 2-3 Layers of blood capillaries. Pigmentation is highest at the distal ends of the secondary and tertiary Lamella where blood capillaries are concentrated and very scanty on the primary and the proximal ends of the secondary lamella where the presence of capillaries is much reduced. In contrast to the capillaries of the pleated pecten, the endothelium of the capillaries in the pecten of the ostrich exhibits very few microvilli. These observations suggest that the morphology of the pecten of the ostrich, a flightless ratite bird is unique to the pleated pecten and is designed to meet the balance between optimal vision and large surface area for blood supply and yet ensuring it is kept firmly erect within the vitreous
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Dreher D., Cochand L., Kok M., Pechere J. C., L. P. Nicod and P. Gehr (2001). Candidate vaccine strains of Salmonella infect and induce profound changes in the morphology of human dendritic cells.Journal of Aerosol Medicine 14: P2-10.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N., Weyrauch, K. D. and P.Gehr (1999). Comparative morphometry of the pecten oculi in domestic fowl (Gallus domesticus), black kite (Milvus migrans) and spotted eagle owl (Bubo africanus).". In: Presented at the Swiss Society for Anatomie, Histology and Embryology (SGAHE) held in Basel, Switzerland on 13th October 1999. Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Maina, J. N., Bhattacharjee J., and K. D. Weyrauch(2001). Functional morphology of the pecten oculi in the nocturnal spotted eagle owl (Bubo bubo africanus), and the diurnal black kite (Milvus migrans) and the domestic fowl (Gallus gallus va.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., and P. Gehr (2000). Dendritic cells-Particle interaction.". In: Presented at the DKF Research Conference, University of Bern,Switzerland Bern, Switzerland on 14th June 2000. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Rothen-Rutishauser B. M., Kiama S. G., Gehr P. (2005). A three-dimensional cellular model of the human respiratory tract to study the interaction with particles. American Journal of Respiratory Cell and Molecular Biology 32:281-9.". In: Faculty of Veterinary Medicine Biennial Scientific Conference and Exhibition, 6th to 8th September 2006. Elsevier; 2005. Abstract
A novel triple co-culture model of the human airway barrier was designed to simulate the cellular part of the air-blood barrier of the respiratory tract represented by macrophages, epithelial cells, and dendritic cells. When epithelial cells (A549 cells) were grown on filter inserts with pores of 3.0 mum in diameter in a two-chamber system, they formed monolayers with polarization into apical and basolateral domains. The epithelial cell cultures were then supplemented with human blood monocyte-derived macrophages and dendritic cells on the apical and basal aspect, respectively. The single-cell cultures as well as the triple co-cultures were characterized in terms of a number of typical features, for example, morphology of cell types, integrity of epithelial layer, and expression of specific cell surface markers (CD14 for macrophages and CD86 for dendritic cells). The interplay of epithelial cells with macrophages and dendritic cells during the uptake of polystyrene particles (1 mum in diameter) was investigated with confocal laser scanning and conventional transmission electron microscopy. Particles were found in all three cell types, although dendritic cells were not directly exposed to the particles. More investigations are needed to understand the translocation pathway.
GITAHI DRKIAMASTEPHEN. "Walter E., Dreher D., Kok M., Thiele L, Kiama S. G., Gehr P., and H. P. Merkle (2001). Hydrophilic poly (DL-lactide-co-glycolide) microspheres for the delivery of DNA to human-derived macrophages and dendritic cells. Journal of Controlled Release 76: 149-.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Dreher D., Cochand L., Kok M., Pechere J. C., Nicod L. P.,and P. Gehr (2000). Infection of human dendritic cells by Salmonella typhimurium.". In: Presented at the SGAHE 2000 held in Bern, Switzerland on 13th October 2000. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N. and K. D. Weyrauch (1994). Scanning electron microscope study of the pecten oculi of the black kite (Milvus migrans): possible involvement of melanosomes in protecting the pecten against damage by ultraviolet .". In: Presented at the . Elsevier; 1994. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Obregon C., Rothen-Rutishauser B., Kiama S.G., Gehr P., Nicod L. P.(2006). Exovesicles from human activated dendritic cells (DCS) fuse with resting DCS allowing them to present allo-antigens.American Journal of Pathology 169:2127-2136.". In: Journal of Anatomy 213:452-63. Elsevier; 2006. Abstract

Dendritic cells (DCs) can release microvesicles, but the latter's numbers, size, and fate are unclear. Fluorescently labeled DCs were visualized by laser-scanning microscopy. Using a Surpass algorithm, we were able to identify and quantify per cell several hundred microvesicles released from the surface of stimulated DCs. We show that most of these microvesicles are not of endocytic origin but result from budding of the plasma membrane, hence their name, exovesicle. Using a double vital staining, we show that exovesicles isolated from activated DCs can fuse with the membrane of resting DCs, thereby allowing them to present alloantigens to lymphocytes. We concluded that, within a few hours from their release, exovesicles may amplify local or distant adaptive immunological response.

GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Karlsson L. M., Nicod L. P., and P. Gehr (2001). Evaluation of phagocytic activity in human monocyte-derived dendritic cells. Journal of Aerosol Medicine 14: 289-299.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Gehr P., and L. P. Nicod (2000). Infection of human dendritic cells and human alveolar macrophages by Salmonella mutants, a potent vaccine delivery system. American Journal of Respiratory and Critical Care Medicine 161: A128.". In: Fifth NFP37 Somatic Gene Therapy meeting. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N. and K. D. Weyrauch (1997). Surface specialisation of the capillary endothelium in the pecten oculi of the chicken, and their overt roles in pectineal haemodynamics and nutrient transfer to the inner neural ret.". In: Presented at the . Elsevier; 1997. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Dreher, D., Kok M., C. Obregon, Kiama S. G., Gehr P., and L. P Nicod (2002). Salmonella virulence factor SipB induces activation and release of IL-18 in human dendritic cells. Journal of Leukocyte Biology 72:743-751.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2002. Abstract
Interleukin-18 (IL-18) plays an important role in innate and acquired immunity, in particular against intracellular pathogens. However, little is known about the microbial factors that trigger IL-18 secretion by dendritic cells (DCs). To determine the influence of bacterial virulence factors on the activation and release of IL-18, we infected human monocyte-derived DCs with virulence mutants of the facultative intracellular pathogen Salmonella typhimurium. Our results show that infection by S. typhimurium causes caspase-1-dependent activation of IL-18 and triggers the release of IL-18 in human DCs. The secretion of IL-18 by the DCs was closely correlated with the ability of the S. typhimurium strains to induce apoptosis. We demonstrate that activation and release of IL-18 are blocked by mutations in the Salmonella sipB gene, which encodes a virulence factor that activates caspase-1 to induce apoptosis. These findings indicate that the activation and release of IL-18 induced by bacterial virulence factors may represent one component of innate immunity against the intracellular bacteria.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (2001). Functional and Morphological Characterization of Particle .". In: Presented at the Institute of Anatomy, University of Bern, Bern, Switzerland on 15th May 2001. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (1999). Dendritic cell-particle interaction and the potential application(s) in the lung.". In: Presented at the . Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., J. Bhattacharjee, T. N. Kiama , D. K. Mwangi (2003). A Scanning electron microscope Study of Pigment Distribution in Pecten Oculi of the Domestic Fowl and Eagle Owl. The Kenya Veterinarian 26:43-50.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2003. Abstract
In structure-function relationship studies, stereological methods are applied to quantify structural qualities under investigation. In certain organs, like the brain, it is important to count the number of neurons associated with a particular function or region. The count gives an estimate of the electronic units available for a specific task or are endowed with a quantum of electrical energy. Similar studies can be extended in organs like the kidney, glands and muscles. Therefore, stereological methods enhance our knowledge of optimization of structure to funtion in biological design. This paper expounds on the methods used in estimation of number of particles in three-dimensional space. It articulates a historical perspective of the development of particle counting techniques to date in stereology showing how the problem was solved and a sound, practical and unbiased method developed. Two approaches are applied in counting particle number. The model based and the design based approach. The model-based approach assumes that the components under investigation are regular geometrical structures whose parameters can be quantified using regular geometrical methods. This counting method is biased, inefficient and difficult to apply in biological tissues. The design based approach applies a three dimensional sampling probe, the disector and makes no assumptions about shape or size of the components under investigation as in model approach.
GITAHI DRKIAMASTEPHEN. "Dreher D., Obregon C., Kok M., Kiama S.G., Gehr P., and L. P. Nicod(2001). Release of IL-18 by salmonella SipB protein in human antigenpresenting cells. Journal of Aerosol Medicine 14: P2-11.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., and P. Gehr (1999). Phagocytosis in dendritic cells.". In: Presented at the Division of Pneumology, Cantonal Hospital of Geneva, Geneva, Switzerland on 17th December 1999. Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
Gitahi N, Kiarie J, Mecha J, Ilovi S. "Implementation of HIV discordant couple care and treatment program in a Kenyan referral hospital.". In: 8th IAS Conference on Pathogenesis, Treatment and Prevention, Vancouver, . Canada ; 2015.
GITAHI DRKIAMASTEPHEN. "Walter E., Dreher D., Kok M., Thiele L, Kiama S. G., Gehr P., and H.P. Merkle (2001). Hydrophilic poly (DL-lactide-co-glycolide) microspheres for the delivery of DNA to human-derived macrophages and dendritic cells. Journal of Controlled Release 76: 149-1.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (2000). Phagocytosis of particulate antigens by human dendritic cells and its relevance in development of immunity.". In: Presented at the Institute of Anatomy,University of Bern, Bern,Switzerland on 8th June 2000. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Mogoa E. G. M., Wabacha J. K., Mbithi P. M. F., Kiama S. G (2005).An overview of animal welfare issues in Kenya. The Kenya Veterinarian 29:48-52.". In: Faculty of Veterinary Medicine Biennial Scientific Conference and Exhibition, 6th to 8th September 2006. Elsevier; 2005.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (2001). Functional and Morphological Characterization of Particle .". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Dreher D., Kok M., Kiama S. G., Cochand L., Gehr P., and L. P. Nicod(2000). Apoptosis in dendritic cells: Consequences for immunotherapy with Salmonella vectors.". In: Presented at the fourth NFP37 Somatic Gene Therapy meeting held in Fribourg, Switzerland on 6th October 2000. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
Gitahi JN, M.M G, P.B. G, T.W. G, A N. "Multidrug resistant Escherichia coli isolated from asymptomatic school going children in kibera slum, Kenya." African Journal of Bacteriology Research. 2018;10(5):70-77.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N. and K. D. Weyrauch(1994). Scanning electron microscope study of the pecten oculi of the black kite (Milvus migrans): possible involvement of melanosomes in protecting the pecten against damage by ultraviolet l.". In: Presented at the . Elsevier; 1994. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., Dreher D., Cochand L., Kok M., Obregon C., Nicod L. P.,Gehr P. (2006). Host cell responces of Salmonella typhimurium infected human dendritic cells. Immunology and Cell Biology 84:475-481.". In: Journal of Anatomy 213:452-63. Elsevier; 2006. Abstract

Live attenuated Salmonella are attractive vaccine candidates for mucosal application because they induce both mucosal immune responses and systematic immune responses. After breaking the epithelium barrier, Salmonella typhimurium is found within dendritic cells (DC) in the Peyer's patches. Although there are abundant data on the interaction of S. typhimurium with murine epithelial cells, macrophages and DC, little is known about its interaction with human DC. Live attenuated S. typhimurium have recently been shown to efficiently infect human DC in vitro and induce production of cytokines. In this study, we have analysed the morphological consequences of infection of human DC by the attenuated S. typhimurium mutant strains designated PhoPc, AroA and SipB and the wild-type strains of the American Type Culture Collection (Manassas, VA, USA), ATCC 14028 and ATCC C53, by electron microscopy at 30 min, 3 h and 24 h after exposure. Our results show that genetic background of the strains profoundly influence DC morphology following infection. The changes included (i) membrane ruffling; (ii) formation of tight or spacious phagosomes; (iii) apoptosis; and (iv) spherical, pedunculated membrane-bound microvesicles that project from the plasma membrane. Despite the fact that membrane ruffling was much more pronounced with the two virulent strains, all mutants were taken up by the DC. The microvesicles were induced by all the attenuated strains, including SipB, which did not induce apoptosis in the host cell. These results suggest that Salmonella is internalized by human DC, inducing morphological changes in the DC that could explain immunogenicity of the attenuated strains.

GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Maina, J. N., Bhattacharjee J., and K. D. Weyrauch (2001). Functional morphology of the pecten oculi in the nocturnal spotted eagle owl (Bubo bubo africanus), and the diurnal black kite (Milvus migrans) and the domestic fowl (Gallus gallus v.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Dreher D., L. Cochand, Kok M., Pechere J. C., Gehr P., and L. P Nicod (2000). Human Dendritic cells infected with Salmonella typhimurium produce iccosome-like structures. European Respiratory Journal 16: 178s.". In: Fifth NFP37 Somatic Gene Therapy meeting. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N. and K. D. Weyrauch(1997). Surface specialisation of the capillary endothelium in the pecten oculi of the chicken, and their overt roles in pectineal haemodynamics and nutrient transfer to the inner neural reti.". In: Presented at the . Elsevier; 1997. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Dreher, D., Kok M., C. Obregon, Kiama S. G., Gehr P., and L. P Nicod(2002). Salmonella virulence factor SipB induces activation and release of IL-18 in human dendritic cells. Journal of Leukocyte Biology 72:743-751.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2002. Abstract
Interleukin-18 (IL-18) plays an important role in innate and acquired immunity, in particular against intracellular pathogens. However, little is known about the microbial factors that trigger IL-18 secretion by dendritic cells (DCs). To determine the influence of bacterial virulence factors on the activation and release of IL-18, we infected human monocyte-derived DCs with virulence mutants of the facultative intracellular pathogen Salmonella typhimurium. Our results show that infection by S. typhimurium causes caspase-1-dependent activation of IL-18 and triggers the release of IL-18 in human DCs. The secretion of IL-18 by the DCs was closely correlated with the ability of the S. typhimurium strains to induce apoptosis. We demonstrate that activation and release of IL-18 are blocked by mutations in the Salmonella sipB gene, which encodes a virulence factor that activates caspase-1 to induce apoptosis. These findings indicate that the activation and release of IL-18 induced by bacterial virulence factors may represent one component of innate immunity against the intracellular bacteria.
Gitahi NJ, Gathura PB, Gicheru MM, GithinjI TW, Nordin A. "Multidrug resistant Escherichia coli isolated from asymptomatic school going children in Kibera slum, Kenya." African Journal of Bacteriology Research . 2018;10(5):70-77.
GITAHI DRKIAMASTEPHEN. "Dreher D., Kok M., Imboden P., Kiama S. G., Muhindi, D.W., Georgopoulos C., and L. P. Nicod (2001). From genomics to vaccination: treatment of latent tuberculosis by recombinant salmonella.". In: Fifth NFP37 Somatic Gene Therapy meeting. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Bhattacharjee, J., Maina, J. N., Weyrauch, K. D. and P. Gehr (1998). A scanning electron microscope study of the luminal surface specialisations in the blood vessels of the pecten oculi in a diurnal bird, the black kite (Milvus migrans). Ann.". In: Presented at the . Elsevier; 1998. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., J. Bhattacharjee, T. N. Kiama , D. K. Mwangi (2003). A Scanning electron microscope Study of Pigment Distribution in Pecten Oculi of the Domestic Fowl and Eagle Owl. The Kenya Veterinarian 26:43-50.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, 3rd to 5th November 2004. Elsevier; 2003. Abstract
In structure-function relationship studies, stereological methods are applied to quantify structural qualities under investigation. In certain organs, like the brain, it is important to count the number of neurons associated with a particular function or region. The count gives an estimate of the electronic units available for a specific task or are endowed with a quantum of electrical energy. Similar studies can be extended in organs like the kidney, glands and muscles. Therefore, stereological methods enhance our knowledge of optimization of structure to funtion in biological design. This paper expounds on the methods used in estimation of number of particles in three-dimensional space. It articulates a historical perspective of the development of particle counting techniques to date in stereology showing how the problem was solved and a sound, practical and unbiased method developed. Two approaches are applied in counting particle number. The model based and the design based approach. The model-based approach assumes that the components under investigation are regular geometrical structures whose parameters can be quantified using regular geometrical methods. This counting method is biased, inefficient and difficult to apply in biological tissues. The design based approach applies a three dimensional sampling probe, the disector and makes no assumptions about shape or size of the components under investigation as in model approach.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Dreher D., Cochand L., Kok M., Pechere J. C., Nicod L. P.,and P. Gehr (2001). Interaction of Salmonella with human dendritic cells: Production of iccosome-like structures with potential role in antigen presentation.". In: Keystone Symposia on . Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Nicod L. P., and P. Gehr (1999). Stereological assessment of phagocytosis by monocytes, alveolar macrophages and dendritic cells.". In: Presented at the 12th Biennial Congress. International Society for Aerosols in Medicine held in Vienna, Austria on 12th to 16th June 1999). Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
Gitahi MG, Wangoh J, Njage PMK. "Microbial Safety of Street Food in Industrial Area, Nairobi.". 2012. Abstract

Street food play a significant role in feeding urban population with cheap accessible and nutritious foods. Most street foods vendors are not trained on food hygiene and safety........

Gitahi MG, Wangoh J, Njage PMK. "Microbial Safety of Street Food in Industrial Area, Nairobi." Research Journal of Microbiology. 2012.2012-microbial_safety_of_steet_foods.pdf
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Dreher D., Cochand L., Kok M., Pechere J. C., Gehr P., and L. P Nicod (2001). Mutants of Salmonella typhimurium infect human dendritic cells and induce formation of iccosome-like structures.American Journal of Respiratory and Critical Care M.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Nicod L. P., and P. Gehr (1999). Stereological assessment of phagocytosis by monocytes, alveolar macrophages and dendritic cells. Journal of Aerosol Medicine 12 (2): 49.". In: Presented at the Institute of Anatomy,University of Bern, Bern,Switzerland on 8th June 2000. Elsevier; 1999. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Mwangi D. K., Kiama S. G. (2005). Stereological methods for estimation of total number of particles in an organ. The Kenya Veterinarian 29: 33-36.". In: Faculty of Veterinary Medicine Biennial Scientific Conference and Exhibition, 6th to 8th September 2006. Elsevier; 2005.
GITAHI DRKIAMASTEPHEN. "Kiama, S. G., Cochand L., Karlsson L. M., Nicod L. P., and P. Gehr(2001). Evaluation of phagocytic activity in human monocytederived dendritic cells. Journal of Aerosol Medicine 14: 289-299.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Walter E., Dreher, D., Kok M., Thiele L., Kiama S. G., Gehr P., and P. Merkle (2000). Interaction between DNA-loaded poly (DL-lactide-coglycolide)microspheres and human antigen-presenting cells Pharmaceutical Research.". In: Presented at the fourth NFP37 Somatic Gene Therapy meeting held in Fribourg, Switzerland on 6th October 2000. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Bhattacharjee, J., Kiama, S. G., and J. N. Maina (1994). Fine structure of the pecten oculi of the spotted eagle owl with special reference to the surface distribution of melanosomes. Experimental Eye Research 59,S1, 114.". In: Presented at the . Elsevier; 1994. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (2006). Evolving trends in veterinary education. .". In: Faculty of Veterinary Medicine Biennial Scientific Conference and Exhibition, 6th to 8th September 2006. Elsevier; 2006. Abstract
Formal veterinary education began in the Western world in the 1763 in Lyon, 1767 in Vienna and 1791 in London. These institutions were established in an effort to reduce the severe economic impact of animal diseases, particularly, rinderpest. However over time the profession has evolved in line with emerging issues such as animal welfare, food safety, the environment and advancement in information computer technology. Furthermore, consumers and clients are increasingly well informed, and the professionals no longer have a monopoly of knowledge in their area. Moreover, the hitherto assumption that an initial degree would confers one unlimited, life-long license to practice without any need for continuing education is being questioned. Furthermore, there is continued pressure on university resources, as well as problems in attracting competent clinical staff to teach in areas of specialization and, the universities are being expected to achieve more and more with fewer resources. The structure of the profession is also gradually changing with a move towards more specialist practices, but with mixed practice still an important employer of veterinary surgeons in rural areas. In addition, there is growing awareness that the amount of veterinary knowledge is expanding all the time and it is not possible anymore, for undergraduates to achieve high levels of expertise in all areas of the veterinary profession during the 4 to 6 years available for training. These issues have continued to model the evolution of the veterinary education. The evolution has mainly focused on 6 main areas namely, review on admission criteria and curriculum review, adoption of new teaching methods, collaboration with private clinicians, introduction of apprenticeship and mandatory continuing veterinary education. This paper will elaborate on the evolving trends in veterinary education as defined by each of
GITAHI DRKIAMASTEPHEN. "Dreher, D., Cochand L., Kok M., Kiama S. G., Gehr P., Pech.". In: Faculty of Veterinary Medicine Biennial Scientific Conference 2002. Elsevier; 2001. Abstract
Dendritic cells play a central role in initiation of primary T lymphocyte responses to foreign antigens. Their potency in antigen presentation vis-a-vis reported low or lack of ability to phagocytize particulate matter has limited our understanding of the role that they play in inducing immunity to particulate antigens. One hypothesis is that dendritic cells may possess a high phagocytic capacity when immature and located in peripheral tissues, which they lose on maturation. Our goal was to characterize the phagocytic capacity in human immature dendritic cells. The phagocytic capacity of human monocyte-derived immature dendritic cells was studied by morphological and morphometric means, and compared to that of professional phagocytes, human alveolar macrophages, their progenitors, the peripheral blood monocytes, and mature dendritic cells. Phagocytic index (proportion of phagocytic cells) was decreased by 42.8% (immature dendritic cells) and 74.2% (mature dendritic cells) with respect to monocytes. Similarly, the phagocytic index was decreased by 46.5% (immature dendritic cells) and 75.9% (mature dendritic cells) with respect to macrophages. Volume density of phagocytized particles was decreased by 76.1% (immature dendritic cells) and 96.7% (mature dendritic cells) with respect to the monocytes. However, volume density was decreased by 34.3% (immature dendritic cells) and 91% (mature dendritic cells) with respect to alveolar macrophages. These results show that human monocyte-derived immature dendritic cells possess a phagocytic capacity that is lower than that of peripheral blood monocytes and alveolar macrophages but higher than that of mature dendritic cells.
GITAHI DRKIAMASTEPHEN. "Bhattacharjee J., and S. G. Kiama (2000). Distribution of melanocytes in the pecten oculi of diurnal domestic fowl and nocturnal spotted eagle owl. Experimental Eye Research Vol. 71, Supplement 1, p205.". In: Fifth NFP37 Somatic Gene Therapy meeting. Elsevier; 2000. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
Gitahi N, Gicheru MM, Gathura PB, Karanja NK, Githinji WT, Nordin A. "Internalization of enteropathogenic human bacteria in lettuce and coriander plant tissue." ISABB Journal of Health and Environmental Sciences. 2018;Vol. 5(3): 28-32.
GITAHI DRKIAMASTEPHEN. "Kiama S. G. (1995). Morphology and Morphometry of the Pecten Oculi: A Comparative Study. Masters of Science in Veterinary Anatomy, University of Nairobi, Kenya.". In: Presented at the . Elsevier; 1995. Abstract
Recent publications have demonstrated that the protease caspase-1 is responsible for the processing of pro-interleukin 18 (IL-18) into the active form. Studies on cell lines and murine macrophages have shown that the bacterial invasion factor SipB activates caspase-1, triggering cell death. Thus, we investigated the role of SipB in the activation and release of IL-18 in human alveolar macrophages (AM), which are the first line of defense against inhaled pathogens. Under steady-state conditions, AM are a more important source of IL-18 than are dendritic cells (DC) and monocytes. Cytokine production by AM and DC was compared after both types of cells had been infected with a virulent strain of Salmonella enterica serovar Typhimurium and an isogenic sipB mutant, which were used as an infection model. Infection with virulent Salmonella led to marked cell death with features of apoptosis while both intracellular activation and release of IL-18 were demonstrated. In contrast, the sipB mutant did not induce such cell death or the release of active IL-18. The specific caspase-1 inhibitor Ac-YVAD-CMK blocked the early IL-18 release in AM infected with the virulent strain. However, the type of Salmonella infection did not differentially regulate IL-18 gene expression. We concluded that the bacterial virulence factor SipB plays an essential posttranslational role in the intracellular activation of IL-18 and the release of the cytokine in human AM.
GITAHI DRKIAMASTEPHEN. "Kiama S. G., Maina J. N., Bhattacharjee J., Mwangi D. K., Macharia R. G., Weyrauch K. D. (2006). The Morphology of the pectin oculi of the ostrich, Struthio camelus. Annals of Anatomy 188:516-528.". In: Journal of Anatomy 213:452-63. Elsevier; 2006. Abstract
The pecten oculi is a structure peculiar to the avian eye. Three morphological types of pecten oculi are recognized: conical type, vaned type and pleated type. The pleated type has been well studied. However, there exists only scanty data on the morphology of the latter two types of pectens. The structure of the vaned type of pecten of the ostrich, Struthio camelus was investigated with light and electron microscope. The pecten of this species consists of a vertical primary lamella that arises from the optic disc and supports 16-19 laterally located secondary lamellae, which run from the base and confluence at the apex. Some of the secondary lamellae give rise to 2 or 3 tertiary lamellae. The lamellae provide a wide surface, which supports 2-3 Layers of blood capillaries. Pigmentation is highest at the distal ends of the secondary and tertiary Lamella where blood capillaries are concentrated and very scanty on the primary and the proximal ends of the secondary lamella where the presence of capillaries is much reduced. In contrast to the capillaries of the pleated pecten, the endothelium of the capillaries in the pecten of the ostrich exhibits very few microvilli. These observations suggest that the morphology of the pecten of the ostrich, a flightless ratite bird is unique to the pleated pecten and is designed to meet the balance between optimal vision and large surface area for blood supply and yet ensuring it is kept firmly erect within the vitreous.
Gitao CG, Maina SM, Kihu SM. . Enhanced Diagnosis of peste des petits ruminants (PPR) using experimental infection models. Nairobi Jacaranda Hotel, Westlands Nairobi-Kenya 9th – 10th June: FAO-EU; 2015.
Gitao G, Maina S, Gathumbi P. Experimental infection of Peste des petits ruminants disease in Kenya. Lap Lambert Academic Publishing; 2016.978-3-659-97197-6-1.pdf
Gitao CG, Kihu SM, Muse AE, Wanjohi M. "Lessons from interaction of researchers with pastoralists from eastern Africa." African Journal of Rural Development. 2016;1(3):271-280.
Gitao CG, S.M.Kihu, Bebora LC, Njenga JM, Wairire GG, Karimuribo E, P S, Wahome R, Maingi N. "Developing capacity for implementing innovative PPR control strategies based on the epidemiology and socio-economic aspects of the disease in the East African region.". In: Second RUFORUM Biennial Meeting. Kampala, Uganda; 2010.gitao.pdf
Gitao CG, Mbindyo C, Bebora L. Dairy Goat Milk Hygiene: Analyses in Mt Kenya Region. OmniScriptum Marketing DEU GmbH Heinrich-Böcking-Straße 6-8 D - 66121 Saarbrücken: LAP LAMBERT Academic Publishing; 2014.978-3-659-61078-3_coverpreview2.pdf
Gitao CG, Njihia LW, Lamuka P. "Prevalence and risk of milk-borne microbes from camels. Potential microbes from camel milk in Isiolo County, Kenya." Lap Lambert Academic Publishing a trademark of Omni scriptum S.R.L Publishing group. 2021;(ISBN- 978-620-3-93087-0.).
Gitao C, Mbindyo C, Omani R, Chemenwo V. "Review of Sheep Pox Disease in Sheep." Journal of Veterinary medicine and Research. 2017;4(1):1068.review_of_sheep_pox.pdf
Gitao, C.G., Toroitich, K, Khalif, Field, C, Wario, S. Mass Livestock Deaths In EL-HADI Of North-Horr Sub-County, MARSABIT COUNTY. Nairobi: RPLP; 2019.marsabit_camel_deaths-paper_-1.docx
Gitao CG, Njihia LW, Lamuka P. 'Prevalence and risk of milk-borne microbes from camels" Potential microbes from camel milk in Isiolo county, Kenya. Nairobi: lAP Lambert Academic Publishing; 2021.
Gitao CG, Kihu SM, Muse AE. Comparison of Peste des petits ruminants in Kenya and Tanzania.. in Nairobi Jacaranda Hotel, Westlands Nairobi-Kenya 9th – 10th June: FAO-EU ; 2015.comparison_of_peste_des_petits_ruminants_ppr.pptx
Gitao G, Kibore B, Sangula A. Seroprevalence of foot and mouth disease in Kenya. Saarbrucken: Lap Lambert Academic Publishing; 2016.978-3-330-01103-8.pdf
Gitao, C G; Kihu BNWKSWMSM; LC;. Developing capacity for implementing innovative PPR control strategies based on the epidemiology and socio-economic aspects of the disease in the East African region.; 2010. Abstract

Major losses in sheep and goats have been incurred from Peste des petit ruminants (PPR), a relatively new disease in East Africa. It first appeared in Eastern Uganda but has since spread to most of Kenya and Northern Tanzania. Small ruminants are the source of income for most pastoralists in East Africa. In this study the epidemiology of PPR including risk factors, prevalence, and socio-economic effects will be analyzed using participatory tools in Turkana, Kenya and Longido in Tanzania.

Gitao CG, Kihu S, Maina SM. "Review of Peste Des petits ruminants in sheep." Journal of Veterinary Medicine and Research. 2016;3(5):1060.
Gitao CG, Kihu SM, Bebora LC, Njenga JM, Wairire GG, Maingi N, Muse E, E K, Misinzo G, Mellau LSB, Msoffe PLM, Swai ES, Albano. "Comparison of Peste des petits ruminants (PPR) disease between Tanzania and Kenya.". In: Third Ruforum Biennial Meeting. Kampala, Uganda; 2012.gitao_523_3.pdf
Gitao, C.G. "PhD supervision at University of Nairobi.". In: Carta Supervision workshop. Johannesburg, South Africa; 2018.
Gitao, C.G. Current Research Projects. Nairobi: Dept Vet Pathology; 2014.current_research-.pdf
Gitao C, Wanjohi G, Bebora L, Muchemi, L. "Camel Milk Quality and Bacterial Contamination along Market Chain in Wajir and Garissa Counties of Kenya." Journal of Veterinary Medicine and Animal Health. 2017;4(10):1114.
Gitao CG, Bebora L. "Subclinical mastitis affecting hygienic quality of marketed camel milk from North - Eastern Province, Kenya.". Submitted. Abstractsubclinical_mastitis_affecting_hygienic_quality_of.pdfWebsite

North Eastern Province, camel is the dominant livestock; it provides subsistence to many people especially during the frequent droughts when other animals either die or are unthrifty. This is beca use camel is highly suited for hot environments. In this region, camels number approximately 3 million and are the main producers of milk for the residents, who are mainly of Somali origin, and are pastoralists. Currentl y, the milk is also sold in Nairobi and other far places; and there is a fast growing demand for it. This has necessitated examination of the milk quality, in response to food safety awareness, especially noting that some of the bacteria causing subclinical mastitis can cause disease in humans. This study was carried out to establish the hygienic quality of camel milk from this area, zeroing down to 2 districts, Garissa and Wajir. T hree hundred and eighty four bulk camel milk samples were collected in volumes of 200 to 300 ml. They wer e transport ed to the laboratory in cold/ice boxes and bacterial isolation and characterization done not later than 24 h after arrival at the laboratory. Before culturing, the milk samples were screened using Ca lifornia Mastitis Test (CMT); samples testing positive (a n indication of subclinical mastitis) were then subjected to bacteriological investigation, using standard methods. Results of this study have shown that subclin ical mastitis is prevalent in dromedary camels of Garissa and Wajir districts of North Eastern province of Kenya, and that Gram positive cocci ( Staphylococcus and Streptococcus) are the dominant mastitis pathogens isolated. Other isolated bacteria included Klebsiella/Enterobacter, E scherichia coli and Bacillus. The positive correlation of CMT with the presen ce of mastitis pathogens in camel milk showed that CMT is a useful screening test in the detection of subclinical mastitis in camels; it is thus a useful tool for farm ers, aiding them in picking the affected animals, segregating and treating them. The resu lts also contribute towards coming up with respective control measures so as to keep camel milk fresh for longer periods and als o make it safe for human consumption.

Gitao CG, Mbindyo C, Bebora L. "Dairy Goat Milk Hygiene: Analyses in Mt Kenya Region.". 2014. Abstract
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Gitao CG, Wanjohi M, Gitari R, Akweya B, Okoth MW. "The Prevalence of Common Milk Borne Pathogens of Camelus Mastitis Origin and their Antibiotic Resistance in North Eastern Province, Kenya." American Journal of Research Communication. 2014;2(7):53-71.
Gitao, C.G., Khalif, others. Validation of camel milk standards. Isiolo, 8-11 May: KEBS; 2016.dks_2062_2016__pasteurized_camel___milk_1.docx
Gitao, C.G. Reviewer, Transboundary and Emerging diseases. Trsansboundary and Emerging Diseases; 2020.tbed_reviewer_certificate_1_1.pdf
Gitao CG. Camel milk value chain in Kenya. University of Kassel in Witzenhausen 2 - 10. Feb 2015; BIOFACH 2015" in Nürnberg 11-13, feb 2015: DAAD ALUMNI; 2015.safari.pdf
Gitao CG, Akundabweni LSM. "Creation of research linkages in Africa by regional bodies.". In: Third Ruforum Biennial Meeting. Kampala, Uganda; 2012.creation_of_networks.docx
Gitao, C.G., Orono, S, Cook, A. How to Diagnose Malignant Catarrhal fever and views from Pastoralists. Saarbrucken: Lap Lambert Academic Publishing; 2019.978-620-0-10122-8_coverpreview_2.pdf
Gitao, C.G., Bebora, L.C., Wanjohi. G. Camel Mik Hygiene: Analysis of Camel Milk contamination in Garissa and Wajir Counties in Kenya. OmniScriptum Marketing DEU GmbH Heinrich-Böcking-Straße 6-8 D - 66121 Saarbrücken: LAP LAMBERT Academic Publishing; 2014.978-3-659-58174-8_coverpreview2.pdf
Gitao C. "Role of Academia and Researchers in the Agricultural sector in Kenya’.". In: Kenya Private Sector Agricultural sector. Intercontinental Hotel, Nairobi; 2019.
Gitao C.G. UoN vet-German student exchange programme. Nairobi/Berlin: UoN/Free University of Berlin; 2014.uon_students_and_german_students.pdf
Gitari A, Nguhiu J, Varma V, Mogoa E. "Occurrence, treatment protocols, and outcomes of colic in horses within Nairobi County, Kenya." Veterinary world. 2017;10(10):1255.
Gitari A, Nguhiu J, Varma V, Mogoa E. "Occurrence, treatment protocols, and outcomes of colic in horses within Nairobi County, Kenya." Veterinary World. 2017;10(10):1255-1263.
Gitari JN;, Mugendi DN;, Mureithi JG;, Kung'u JB;, Gachene CKK. "The role of plant residues in soil productivity: farmers'knowledge and practices in Embu District, Kenya."; 2003. Abstract

Plant residues from trees, crops or weeds play an important role in determining the soil fertility status in smallholder farmers of the central highlands of Kenya region. A study was conducted in Embu district of Kenya, located in the densely populated windward side of the south-eastern slopes of Mount Kenya, to document farmers knowledge and practices in the prevalence and utilisation ofthese residues. A total of 134 small-scale . farmers cutting across five major agro ecological zones of the 30 kIn transect were interviewed. Farmers indicated that trees, Degraded soils are a major constraint to crops or weed residues found in their farms agricultural production and food security in were associated with generation of plant the central highland of Kenya region residues which either improve or impoverish (Smaling, 1997; Hudgens 1996). The the farm niches where they are found. Plant traditional residues that were associated with soil Long term experiments provide some fertility enhancement included: Zea mays, insights in the consequences of land Physeolus vulgaris, Grevillea robusta, management strategies that cannot be Combretum molle, Cordia africana, Ficus obtained through other means. For instance, sycomorous, and Camellina sinensis. On the trials established at Kenya Agricultural other hand, the residues of Eucalyptus Research Institute land at Kabete near saligna, Macadamia integrifolia, Cupressus Nairobi have shown that the soil organic lusitanica, Croton megalocarpus, Acacia matter declined from 2.1 % (in the original meamsii, Sorghum bicolour and Mangifera coffee estate) to 1.2% C after planting a indica continued to impoverish the soil in the maize-beans rotation over a period of twenty farm fields where they occur. The farmers years (Kapkiyai et al., 1999). Swift and attributed the good or poor crop Woomer (1993) state that it is not the loss performance in farm sections with certain of the soil carbon which poses the threat to types of plant residues to the decomposability the smallholder livelihood, but rather the assocated decline in crop yields resulting from degraded soils. Th euse of plant residues play a crucial role in the long-term improvement of soil physical and chemical properties.

Gitari HI, Gachene CKK, Karanja NN, Kamau S, Nyawade S, Schulte-Geldermann E. "Potato-legume intercropping on a sloping terrain and its effects on soil physico-chemical properties.". 2019.
Gitari AN, Nguhiu-Mwangi J, Mogoa EM, Varma VJ, Mwangi WE, Konde AM, Rashid FK. "Hematological and biochemical changes in horses with colic in Nairobi county, Kenya." International Journal of Veterinary Science. 2016;5(4):250-255.
Gitari HI, Nyawade SO, Kamau S, Gachene CKK, Karanja NN, Schulte-Geldermann E. "Increasing potato equivalent yield increases returns to investment under potato-legume intercropping systems.". 2019.
Gitari A, Nguhiu J, Varma V, Mogoa E. "Occurrence, treatment protocols, and outcomes of colic in horses within Nairobi County, Kenya." Veterinary World. 2017;10:1255-1263. Abstract
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Gitari A, Nguhiu J, Varma V, Mogoa E. "Occurrence, treatment protocols, and outcomes of colic in horses within Nairobi County, Kenya, Veterinary World, 10 (10): 1255-1263.". 2017. Abstract

Aim: The aim of this study was to determine the treatments and their outcomes in horses with colic in Nairobi County, Kenya.
Materials and Methods: This is a retrospective study to determine the occurrence, treatments, pain management, and outcomes of colic in horses in Nairobi County. Association between pain management protocols and the outcomes of colic with regard to recovery or death was also determined. Data collected from four equine practitioners were organized manually and given numerical codes as appropriate to facilitate entry into the computer. The coded data were entered into Microsoft Excel 2010 and exported to StatPlus pro 5.9. 8 statistical package for analysis. Simple association tests were done between various factors and occurrence of colic.
Results: The incidence of colic for the 11 years was 3.1%, which constituted 68.0% spasmodic colic, 27.8% impaction colic, and 4.2% displacement …

Gitari HI, Shadrack N, Kamau S, Karanja NN, Gachene CKK, Schulte-Geldermann E. "Agronomic assessment of phosphorus efficacy for potato (Solanum tuberosum L) under legume intercrops.". 2019.
Gitari A, Nguhiu J, Varma V, Mwangi W, Konde A, Rashid F. "Hematological and Biochemical Changes in Horses with colic in Nairobi County, Kenya." International Journal of Veterinary Science. 2016;5(4):250-255.
Gitari JN;, Mugendi, D.N.;, Kung’u JB;, Mureithi JG;, Gachene CKK;, Muna MM. "The Role Of Agroforestry Trees In Soil Productivity: Verification Of Farmers’ Knowledge A Nd Perceptions In Central Kenya Highlands."; 2003.
Gitari HI, Gachene CKK, Karanja NN, Kamau S, Nyawade S, Schulte-Geldermann E. "Potato-legume intercropping on a sloping terrain and its effects on soil physico-chemical properties.". 2019.
Gitari A, Nguhiu J, Varma V, Mwangi W, Konde A, Rashid F. "Hematological and Biochemical Changes in Horses with colic in Nairobi County, Kenya." International Journal of Veterinary Science. 2016;5:250-255. Abstract
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Gitari AN, Nguhiu-Mwangi J, Mogoa EM, Varma VJ, Mwangi WE, Konde AM, Rashid FK, others. "Hematological and biochemical changes in horses with colic in Nairobi county, Kenya." International Journal of Veterinary Science. 2016;5:250-255. Abstract
n/a
Gitari HI, Nyawade SO, Kamau S, Karanja NN, Gachene CKK, Raza MA, Maitra S, Schulte-Geldermann E. "Revisiting intercropping indices with respect to potato-legume intercropping systems.". 2020.
Gitau AN, Gumbe LO. "Triaxial testing of an agricultural soil. ISBN 7-80167-707-2.". In: 2004 CIGR International Conference. Beijing, China; 2004.
GITAU DRTHAIYAHANDREW. "Thaiya, A.G (1992). Cassia didymotrya Fres and Solanum incanum L in rats.". In: MSc thesis, Faculty of vet. medicine, university of Nairobi. Thesis; 1992. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau AK2021, Oyieke FA, Wolfgang Richard Mukabana. "Assessment of the role played by domestic animals in jigger infection in Kandara sub-county, Kenya (case control study)." Pan African Medical Journal. 2021;39:231.2021-1.pdf
Gitau GK;, Aleri JW;, Mbuthia PG;, Mulei C. "Major causes of calf mortality in peri-urban area of Nairobi, Kenya."; 2010.
GITAU DRTHAIYAHANDREW. "Thaiyah, A.G. (1996). Differential diagnosis of Eye diseases in cattle. Annual scientific conference of the central KVA branch held at Greenhills Hotel, Nyeri, 16-17/9/96.". In: Proc. S. & E. Afr. Rabies group. ILRI, 4-6TH March. Nbi, Kenya. KVA central branch annual SC. conference; 1996. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau AK, Oyieke FO, Mukabana WR. "Assessment of tungiasis management knowledge in Kandara sub county, Kenya." Journal of Entomology and Zoology Studies. 2021;9(4):127-136.
GITAU DRTHAIYAHANDREW, M DRMUNYUASJ. "Munyua .S.J.M, Mbai ,K, Thaiya , A.G., Wabacha, J.K. and Tsuma V.T.(1999). Reproductive health care in Dairy animals. Central artificial Insemination Station Magazine, October 1999, pp 25-26.". In: Central artificial Insemination Station Magazine, October 1999, pp 25-26. Central artificial Insemination Station Magazine; 1999. Abstract
Forty-two pigs in a herd of 117 displayed various clinical signs of progressive atrophic rhinitis. The main signs included sneezing, coughing, lachrymation, serous to mucopurulent nasal discharge, and nasal bleeding in 1 pig. Three pigs had lateral deviation of the snout, while 4 had brachygnathia superior with obvious deformation of the face. Four acutely affected weaner pigs appeared weak, while the 7 chronically-affected pigs appeared smaller than their apparently unaffected penmates of the same age. Treatment of the acutely affected pigs with long-acting oxytetracycline at 20 mg/kg body weight intramuscularly, repeated once after 7 days, reduced the severity but did not clear the sneezing from all the pigs. Fifteen pigs were slaughtered 2 months after the clinical diagnosis was made. The carcasses of the chronically affected pigs were about 15% lighter than those of the apparently normal pigs of the same age and from the same pen, which translated to a loss of 921.00 Kenya shillings per pig (US$13.7). Diagnosis of progressive atrophic rhinitis was confirmed by sectioning the snouts of randomly selected slaughtered pigs with obvious deformation of the snout. Sections were made at the level of the 1st/2nd upper premolar tooth. Varying degrees of turbinate atrophy, from mild to complete, were noted. Histopathology of the turbinates revealed metaplasia of nasal epithelium and fibrosis in the lamina propria
GITAU DRTHAIYAHANDREW. "J.K. Wabacha, G.K. Gitau, J.M. Nduhiu, A.G. Thaiyah, P.M.F. Mbithi and S.J.M. Munyua(1998). An outbreak of urticarial form of swine erysipelas in a medium -scale piggery in Kiambu district, Kenya. Journal of South African Veterinary Association 69(2): 61-.". In: Kenya Veterinary Assciation Central branch Scientific Seminar, 16th - 17th October, 1997, Nyeri, Kenya. Journal of South African Veterinary Association; 1998. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau, A.N., Ayub, Njoroge; Gumbe P(S)LO. Mechanical behaviour of a hardsetting luvisol soil Gitau, Ayub, Njoroge; Gumbe, L.O Prof. (Supervisor) .; 2004. Abstract

The study applies critical state soil mechanics to model the mechanical behavior of luvisol soils. Field work involved sampling and soil physical characterization to obtain undisturbed and disturbed specimens

Gitau AN. Mechanical Behaviour of a Hardsetting Luvisol soil . Nairobi: Univeristy of Nairobi; 2004.
Gitau W, Camberlin P, Ogallo L, Okoola R. "Oceanic and Atmospheric Linkages with Short Rainfall Season Intraseasonal Statistics over Equatorial Eastern Africa and their Predictive Potential." International Journal of Climatology. 2015;35(9):2382-2399. AbstractRoyal Meteorological Society

Despite earlier studies over various parts of the world including equatorial Eastern Africa (EEA) showing that intraseasonal statistics of wet and dry spells have spatially coherent signals and thus greater predictability potential, no attempts have been made to identify the predictors for these intraseasonal statistics. This study therefore attempts to identify the predictors (with a 1‐month lead time) for some of the subregional intraseasonal statistics of wet and dry spells (SRISS) which showed the greatest predictability potential during the short rainfall season over EEA. Correlation analysis between the SRISS and seasonal rainfall totals on one hand and the predefined predictors on the other hand were initially computed and those that were significant at 95% confidence levels retained. To identify additional potential predictors, partial correlation analyses were undertaken between SRISS and large‐scale oceanic and atmospheric fields while controlling the effects of the predefined predictors retained earlier. Cross‐validated multivariate linear regression (MLR) models were finally developed and their residuals assessed for independence and for normal distribution. Four large‐scale oceanic and atmospheric predictors with robust physical/dynamical linkages with SRISS were identified for the first time. The cross‐validated MLR models for the SRISS of wet spells and seasonal rainfall totals mainly picked two of these predictors around the Bay of Bengal. The two predictors combined accounted for 39.5% of the magnitude of the SST changes between the July–August and October–November–December periods over the Western Pole of the Indian Ocean Dipole, subsequently impacting EEA rainfall. MLR models were defined yielding cross‐validated correlations between observed and predicted values of seasonal totals and number of wet days ranging from 0.60 to 0.75, depending on the subregion. MLR models could not be developed over a few of the subregions suggesting that the local factors could have masked the global and regional signals encompassed in the additional potential predictors.

Gitau OJJ &. Business Law. Nairobi: Focus Books; 2010.
GITAU DRTHAIYAHANDREW, N PROFNYAGAP, MATHENGE PROFMARIBEIJAMES. "Experimental Solanum incanum L poisoning in goats. Thaiya, A.G., Nyaga, P.N., Maribei, J.M., Nduati, D., Mbuthia, P.G. and Ngatia, T.A.". In: Bull. Anim. Hlth. Prod. Afr. vol.58. no.1. au-ibar; 2010. Abstract

According to the statements made by a number of scholars, in the 80's East African Anglophone novel, which once received a nickname of "social documentary", began to lose gradually its social commitment. Many of the writers known previously as the most active supporters of the social trend, moved their attempts to other literan areas - criminal novel ("Weapon of hunger" by Meja Mцangi, 1989), love story (Yussuf Dawood's "Off my chest", 1988), even children's literature (books for children in Gikuyu, written by Ngugi wa Thiong'o). However, in the late 80's and early 90's East African Anglophone novel stepped onto a new level of social trend, moving from "social documentary" to "social epic". The authors now are trying to sum up the historical experience of East African countries over a large time span, and to that effect appeal mostly to elaborate and spacious literary forms, such as epic novel. These authors, although chosen one and the same literary form, are showing clearly their inclinations towards different styles of writing. For example, Tanzanian author Moyez Vassanji in his novel "The gunny sack" (1989) makes a rather convincing attempt to replant on East African soil the method of "mythological writing", previously used by such author as Gabriel Garcia Marquez. The novel definitely appeals not only to local reader, but to a wider international audience; on its pages the author manages to restore not only the fate of several generations of Indian family, but even the slightest details of their mentality, using myth as one of the basic means for changing the dimensions of time and space, according to the logic of the narration. The development of Kenyan novel in the early 90's confirms also one of the main tendencies in modem literature - bridging between "elite" and popular fiction. The first attempt of an epic novel in Kenyan Anglophone literature was, oddly enough, made by the veteran of Kenyan popular fiction David Maillu in his "Broken drum" H991). The novel hardly aims the widest reading public - nevertheless, stylistically it bears distinct features of popular fiction, such as crime story, romance, etc. Popular novel in East Africa also shows certain inclination towards urgent social themes, but the authors inevitably uses the artistic means they feel most happy with - that is, the style of popular fiction. For example, the "clash of cultures" - the experience of young Africans studying abroad - is presented in the form of a picaresque ("Times beyond" by Omondi Makoloo, 1992) or love story ("The girl from Uganda" by Tengio Urrio, 1993); feministic problems are spiced with sentimentalism ("Judy the nun" by P .Waweru, 1990); the thoughts on the hardships of younger generation are guised in Bildungs roman ("The plight of succession" by a Tanzanian Prosper Rwegoshora, 1990). At the same time, some authors, who have been ploughing successfully the field of pop fiction for a few decades, show their interest in more elaborate literary forms ("Dedan Kimathi: the real story" by Samuel Kaluga, 1990). All the mentioned facts do not allow us to state that the division into popular and elite novel will disappear within the foreseeable future. However, the most interesting developments seem to take place precisely in the field of bridging between these two branches of East African fiction.

GITAU DRTHAIYAHANDREW. "A case of Newcastle disease in parrots in Nairobi, Kenya. Bebora, L.C., Thaiyah, A.G., Mbuthia, P.G., Njagi, L.W., Ngatia, T.A. and Nyaga, P.N. (2007).". In: Bull. Anim. Hlth. Prod. Afr. 55:292-295. Bull. Anim. Hlth. Prod. Afr; 2007. Abstract

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

Gitau AN, Gumbe LO. "Transition from brittle failure to ductile flow in an irrigatable sandy soil. ." Discovery and Inovation journal. . 2007;19 No. 2 . (1015 – 079X):Pg. 140-146.
GITAU DRTHAIYAHANDREW. "Munyua, S.J.M., Karioki, D.I., Chibeu, D.M., Wabacha, J.K., Thaiya, A.G. Njenga, M.J., Gathuma J.M., and Mitaru, B.M. (2000) Prognostic indicator of postpartum viability of kids born of Escherichia coli vaccinated or unvaccinated does.J. S. Afr Vet Ass.71.". In: Journal of South Africa Veterinary Association. 71(2): 122-124. J. S. Afr. Vet. Ass.; 2000. Abstract
This study was undertaken to determine some blood and other physiological parameters with potential for use as prognostic indicators of viability of newborn goat kids. Of the 143 kids born during the on-farm study, 97 were crosses of Galla x Small East African (SEA) and 46 were pure SEA. The SEA x Galla kids were 46 single males, with a mean body weight at birth of 2.77 +/- 0.22 kg, 43 females with a mean body weight at birth of 2.36 +/- 0.76 kg and 5 and 3 sets of female and male twins (mean body weight at birth of 1.8 +/- 0.19 kg and 2.05 +/- 0.07 kg for the female and male kids, respectively). The SEA kids comprised 36 single male and female kids (mean body weight at birth of 2.48 +/- 0.04 kg and 10 sets of twins (both male and female) (mean body weight at birth of 1.50 +/- 0.04 kg ). Pre-suckling sera obtained on-station from kids born of does vaccinated against Escherichia coli (n = 8) and unvaccinated does (n = 7) had a total protein content of <40.0 g/l and no detectable levels of IgG and A or E. coli antibodies. Sera obtained 12 hours post partum) from kids that survived in both groups contained about 19-22 g of Ig g/l, 50-80 g total protein/l, blood glucose of >5 mmol/l and had an E. coli antibody titre of between 1/160 and 1/640. On the other hand, kids that died within 48 hours of birth (parturient deaths) and had been classified in categories 3 and 4 righting reaction had low (<40 g/l) total protein, low white blood cell count (4,000/ml) and low blood glucose concentration (<4.9 mmol/l). It is concluded that kids with delayed righting reaction (>45 minutes), low rectal temperature (<36 degrees C), low birth weights (<1.5 kg for singles and <1.0 kg for twins), low white blood cells (<4,000/ml), low (<2 mmol/l) blood glucose levels, low total protein (<40.0 g/l), low (<1:160) E. coli antibody titre and IgG (< or =3,350 mg/l) in sera obtained 12 hours after birth have a poor prognosis for survival
Gitau GK, Karioki DI. "The use of preserved colostrum for rearing replacement dairy calves: calf performance, economics and on-farm practicability in Kenya.". 1995. AbstractWebsite

A total of 133 observations on mean daily mass gains from 19 calves reared on either whole milk (control) or preserved colostrum (treatment) were estimated. The control group had a total of 104 observations computed, while the treatment group had a total of 29 observations. There was no significant difference in the overall mean daily mass gains between the treatment and control groups which were 0.2257 and 0.3607 kg, respectively (P < 0.1). Partial budgeting analysis estimated that with an annual calf crop of 80 calves, the use of preserved colostrum would result in a direct saving of an estimated US$1,800 per year for the farm.

GITAU DRTHAIYAHANDREW, N PROFNYAGAP, MATHENGE PROFMARIBEIJAMES. "Experimental Solanum incanum L poisoning in goats. Thaiya, A.G., Nyaga, P.N., Maribei, J.M., Nduati, D., Mbuthia, P.G. and Ngatia, T.A.". In: Bull. Anim. Hlth. Prod. Afr. vol.58. no.1. au-ibar; 2010. Abstract

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

GITAU DRTHAIYAHANDREW. "Wabacha, J.K., Gitau, G.K., Nduhiu, J.M., Thaiya, A.G., Mbithi, P.M.F. and Munyua, S.J.M. (2002). An outbreak of urticarial form of domestic pig Erysipelas in a medium scale piggery in Kiambu District, Kenya. The Kenya veterinarian Vol. 23, 95-97.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, Nairobi, 3rd . The Kenya veterinarian; 2002. Abstract
This case report describes an outbreak of acute dermatophilosis in a large scale dairy herd and highlights that the disease in Kenya could occur in outbreak proportions and in clinically severe form as has been reported in other countries in West and central Africa.We believe that this is the 1st documented outbreak of a severe form of bovine cutaneous dermatophilosis in exotic dairy animals in Kenya.
GITAU DRTHAIYAHANDREW. "J.K. Wabacha, N.P. Gitonga, M.J. Njenga, A.G.Thaiyah and C.M. Mulei (2006). An outbreak of acute bovine dermatophilosis in a large scale dairy herd in Kenya.". In: Bull. Anim. Hlth. Prod. Afri. 54:144-147. Bull. Anim. Hlth. Prod. Afr.; 2006. Abstract
This case report describes an outbreak of acute dermatophilosis in a large scale dairy herd and highlights that the disease in Kenya could occur in outbreak proportions and in clinically severe form as has been reported in other countries in West and central Africa.We believe that this is the 1st documented outbreak of a severe form of bovine cutaneous dermatophilosis in exotic dairy animals in Kenya.
GITAU DRTHAIYAHANDREW. "A.K. Maina, J.K Muthee, Thaiya, A.G and V.T. Tsuma (1991). An outbreak of progressive cataracts of an undetermined cause in a herd of dairy cows.The Indian Journal of Animal Sciences vol. 61 no. 11.". In: MSc thesis, Faculty of vet. medicine, university of Nairobi. The Indian Journal of Animal Sciences; 1991. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau GK;, Aleri JW;, Mbuthia PG;, Mulei C. "Major causes of calf mortality in peri-urban area of Nairobi, Kenya."; 2010.
GITAU DRTHAIYAHANDREW. "Thaiya, A.G., Chege, J.N. and Wekesa, L.S. (1993). Efficacy of buparvaquone in cattle in kiambu district, Kenya. Bull. Anim. Prod. Afr. 41, 333-335.". In: Bull. Anim. Prod. Afr. (a) 41, 333. Bull. Anim. Prod. Afr.; 1993. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau GK, O'Callaghan - JJ CJ, ADAMS. JE, LISSEMORE KD, WALTNER. "McDermott.". 1994.
GITAU DRTHAIYAHANDREW. "Thaiya, A.G. (1997). Clinical observations on cattle rabies in Kiambu District, Kenya. Proc. S. & E. Afr. Rabies group. ILRI, 4-6TH March. Nbi, Kenya.". In: Proc. S. & E. Afr. Rabies group. ILRI, 4-6TH March. Nbi, Kenya. Proc. S. & E. Afr. Rabies group; 1997. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau AN, Gumbe LO, Biamah EK. "Influence of Soil water on Stress-strain Behaviour of a Compacting Soil in Semi arid Kenya." Soil Tillage Research . 2005;(89(2006)):144-154.
Gitau OJJ &. Business Law. Nairobi: Focus Books; 2010.
GITAU DRTHAIYAHANDREW. "Atypical dermatophilosis of sheep in Kenya. J.K. Wabacha, C.M. Mulei, N.P. Gitonga, M.J. Njenga, A.G.Thaiyah and J. nduhiu (2007).". In: J. S. Afr. Vet. Ass. 78(3): 178-181. J. S. Afr. Vet. Ass.; 2007. Abstract

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

Gitau, A.N. "Mechanical Behaviour of Hardsetting Soils, The critical state soil mechanics approach to soil tillage. ISBN: 978-3-8433-7027-1.". In: Mechanical Behaviour of Hardsetting Soils. Nairobi: LAMBAERT publishers; 2010.
GITAU DRTHAIYAHANDREW, M DRMUNYUASJ. "Munyua .S.J.M, Mbai ,K, Thaiya , A.G., Wabacha, J.K. and Tsuma V.T.(1999). Reproductive health care in Dairy animals. Central artificial Insemination Station Magazine, October 1999, pp 25-26.". In: Central artificial Insemination Station Magazine, October 1999, pp 25-26. Central artificial Insemination Station Magazine; 1999. Abstract
This study was undertaken to determine some blood and other physiological parameters with potential for use as prognostic indicators of viability of newborn goat kids. Of the 143 kids born during the on-farm study, 97 were crosses of Galla x Small East African (SEA) and 46 were pure SEA. The SEA x Galla kids were 46 single males, with a mean body weight at birth of 2.77 +/- 0.22 kg, 43 females with a mean body weight at birth of 2.36 +/- 0.76 kg and 5 and 3 sets of female and male twins (mean body weight at birth of 1.8 +/- 0.19 kg and 2.05 +/- 0.07 kg for the female and male kids, respectively). The SEA kids comprised 36 single male and female kids (mean body weight at birth of 2.48 +/- 0.04 kg and 10 sets of twins (both male and female) (mean body weight at birth of 1.50 +/- 0.04 kg ). Pre-suckling sera obtained on-station from kids born of does vaccinated against Escherichia coli (n = 8) and unvaccinated does (n = 7) had a total protein content of <40.0 g/l and no detectable levels of IgG and A or E. coli antibodies. Sera obtained 12 hours post partum) from kids that survived in both groups contained about 19-22 g of Ig g/l, 50-80 g total protein/l, blood glucose of >5 mmol/l and had an E. coli antibody titre of between 1/160 and 1/640. On the other hand, kids that died within 48 hours of birth (parturient deaths) and had been classified in categories 3 and 4 righting reaction had low (<40 g/l) total protein, low white blood cell count (4,000/ml) and low blood glucose concentration (<4.9 mmol/l). It is concluded that kids with delayed righting reaction (>45 minutes), low rectal temperature (<36 degrees C), low birth weights (<1.5 kg for singles and <1.0 kg for twins), low white blood cells (<4,000/ml), low (<2 mmol/l) blood glucose levels, low total protein (<40.0 g/l), low (<1:160) E. coli antibody titre and IgG (< or =3,350 mg/l) in sera obtained 12 hours after birth have a poor prognosis for survival
GITAU DRTHAIYAHANDREW. "Bovine papillomatosis and its management with an autogenous virus vaccine in Kiambu district, Kenya. Kenya veterinarian. Thaiyah, A.G., Gitau, P., Gitau, G.K., and Nyaga, P.N. (2010).". In: Bull. Anim. Hlth. Prod. Afr. vol.58. no.1. kenya veterinarian: 33: 6-19; 2009. Abstract

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.

Gitau, A.N., L. K, Mganilwa ZM. "Mechanization status in the lake Victoria of East Africa." AJAE.. 2010;Vol. 1(5):(ISSN-1836-9448):160-164.
GITAU DRTHAIYAHANDREW. "Thaiya, A.G., Gitau, G.K. and Mugambi, J.J. (2001). Outbreaks of bovine rabies in Kiambu District, Kenya. Kenya Veterinarian Vol. 21, 10-11.". In: Kenya Veterinarian Vol. 21, 10-11. Kenya Veterinarian; 2001. Abstract
This case report describes an outbreak of acute dermatophilosis in a large scale dairy herd and highlights that the disease in Kenya could occur in outbreak proportions and in clinically severe form as has been reported in other countries in West and central Africa.We believe that this is the 1st documented outbreak of a severe form of bovine cutaneous dermatophilosis in exotic dairy animals in Kenya.
Gitau AN, Mbuge DO, Mutuli GP. "Convective Drying Modelling Approaches: A Review for Herbs, Vegetables, and Fruits. Journal of Biosystems Engineering. South Korea;." Journal of Biosystems Engineering. South Korea;. 2020;Vol. 45(ISSN 2234-1862):197-212.
Gitau PW, Kunyanga CN, Abong’ GO, Ojiem JO, Muthomi JW. "Assessing Sensory Characteristics and Consumer Preference of Legume-Cereal-Root Based Porridges in Nandi County." Journal of Food Quality. 2019;https://doi.org/10.1155/2019/3035418.
GITAU DRTHAIYAHANDREW. "M. J. Njenga, J.N. Kuria, R.G. Wahome, P.B. Gathura, A.G.Thaiya, C.G. Maina, J. Mwangi (2006). An investigation into a Human Anthrax outbreak in Maragua District, Central Kenya. Kenya veterinarian Vol. 30 (2) 62-67.". In: Bull. Anim. Hlth. Prod. Afri. 54:144-147. Kenya veterinarian; 2006. Abstract
This case report describes an outbreak of acute dermatophilosis in a large scale dairy herd and highlights that the disease in Kenya could occur in outbreak proportions and in clinically severe form as has been reported in other countries in West and central Africa.We believe that this is the 1st documented outbreak of a severe form of bovine cutaneous dermatophilosis in exotic dairy animals in Kenya.
Gitau 2. AK, Oyieke FA, Wolfgang Richard Mukabana. "Assessment of tungiasis management knowledge in Kandara sub county Mukabana, ." Journal of Entomology and Zoology studies. 2021;9(4):127-136.2021-2.pdf
Gitau GK, Perry BD, Katende JM, McDermott JJ, Morzaria SP, Young AS. "The prevalence of serum antibodies to tick-borne infections in cattle in smallholder dairy farms in Murang'a District, Kenya; a cross-sectional study.". 1997. Abstract

The most important tick-borne disease of cattle in eastern, central and southern Africa is East Coast fever (ECF) caused by Theileria parva and transmitted by the tick Rhipicephalus appendiculatus. Other less-important tick-borne diseases in cattle are benign theileriosis caused by Theileria mutans, babesiosis caused by Babesia bigemina, anaplasmosis caused by Anaplasma marginale and cowdriosis caused by Cowdria ruminatum. In Murang'a District, Central Province of Kenya, five agroecological zones (AEZs) are defined according to climate, altitude and agricultural activities. A cross-sectional serological study was conducted on 750 smallholder dairy farms in Murang'a District, selected in a stratified random sampling method. The farms had a total of 362 calves. One hundred and fifty farms were studied from three administrative sublocations in each of the five AEZs. Prevalence of serum antibodies to three tick-borne parasites, that is T. parva, T. mutans and B. bigemina, were determined using the enzyme-linked immunosorbent assay (ELISA) technique. Antibody prevalence values differed across the AEZs. The ranges of means for the prevalences were: T. parva (18–72%), T. mutans (1.5–28%) and B. bigemina (12–49%). The above results serve as indicators of the possible existence of endemic stability in some AEZs for some parasites.

Gitau AN, Mutai EBK, Aganda AA, Karuri GE. "Dynamic modeling of Temperatures in Poultry Structures.". 2010.Website
and Gitau AN, Gumbe LO. "Alleviating hard pan formation in the semi-arid Kenya soils for conservation farming. .". In: Regional Workshop on Conservation Agriculture and Rainwater Harvesting. Adidas Ababa, Ethiopia.; 2004.
GITAU DRTHAIYAHANDREW. "Maina, A.K., Munyua, S.J.M., Mutiga, E.R. and Thaiya, A.G. (1993). Mammary gland infections in free range goats in Kenya. Bulletin Animal Production Africa 41:333.". In: Bull. Anim. Hlth. Prod. Afr. 41: 33. Bulletin Animal Production Africa; 1993. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau GK, Bundi RM, Vanleeuwen J, Mulei CM. "Evaluation of PetrifilmsTM as a diagnostic test to detect bovine mastitis organisms in Kenya." Trop Anim Health Prod. 2013;45(3):883-886. Abstracttrop_anim_health_prod-2013.pdf

The study purpose was to validate PetrifilmsTM (3M Microbiology, 2005) against standard culture methods in the diagnosis of bovine mastitis organisms in Kenya. On 128 smallholder dairy cattle farms in Kenya, between June 21, 2010 and August 31, 2010, milk samples from 269 cows that were positive on California Mastitis Test (CMT) were cultured using standard laboratory culture methods and PetrifilmsTM (Aerobic Count and Coliform Count –3M Microbiology, 2005), and results were compared. Staphylococcus aureus was the most common bacterium isolated (73 % of samples). Clinical mastitis was found in only three cows, and there were only two Gram-negative isolates, making it impossible to examine the agreement between the two tests for Gram-negative- or clinical mastitis samples. The observed agreement between the standard culture and PetrifilmTM (3M Microbiology, 2005) results for Gram-positive isolates was 85 %, and there was fair agreement beyond that expected due to chance alone, with a kappa (κ) of 0.38. Using culture results as a gold standard, the PetrifilmsTM had a sensitivity of 90 % for Gram-positive samples and specificity of 51 %. With 87 % of CMT-positive samples resulting in Gram-positive pathogens cultured, there was a positive predictive value of 93 % and a negative predictive value of 43 %. PetrifilmsTM should be considered for culture of mastitis organisms in developing countries, especially when Gram-positive bacteria are expected.

Gitau GK;, Aleri JW;, Mbuthia PG;, Mulei C. "Major causes of calf mortality in peri-urban area of Nairobi, Kenya."; 2010.
GITAU DRTHAIYAHANDREW. "Munyua S. J. M. Wabacha, J. and Thaiya, A. G (1996). Infertility in dairy cattle with special emphasis to those kept under zero grazing units. Annual scientific conference of the central KVA branch held at Greenhills Hotel, Nyeri, 16-17/9/96.". In: Proc. S. & E. Afr. Rabies group. ILRI, 4-6TH March. Nbi, Kenya. KVA central branch annual Sc. Conference; 1996. Abstract
This report concerns an outbreak that occurred during July/August 1997. Ten pigs from a herd of 181 pigs in a medium-scale, semi-closed piggery in Kiambu District, Kenya, contracted the clinical disease. The main clinical findings in affected pigs included: fever (40.5-41.8 degrees C), prostration, inappetence, dog-sitting posture, abortion, erythema and raised, firm to the touch and easily palpated light pink to dark purple diamond-shaped to square/rectangular spots on the skin around the belly and the back. Based on the pathognomonic skin lesions, a clinical diagnosis of swine erysipelas was made. The diagnosis was confirmed by the isolation of Erysipelothrix rhusiopathiae organisms from the blood and skin biopsies taken from the affected pigs. Response to treatment with a combination of procaine penicillin and dihydrostreptomycin at the dosage rate of 20,000 IU/kg body weight (based on procaine penicillin) for 3 days was good and all the affected pigs recovered fully. The farm was placed under quarantine to prevent spread of the disease
Gitau CMW, Gor SO. "Measuring Factor Productivity of the Banking Sector in Kenya." OIDA International Journal of Sustainable Development. 2011;2(12):1-18.
Gitau J, GATARI MJ, Pant HJ. "Investigation of flow dynamics of porous clinkers in a ball mill using technitium-99m as a radiotracer." Applied Radiation and Isotopes. 2019. AbstractWebsite

A radiotracer investigation was carried out in a ball mill of a cement plant in Kenya. Residence time distribution (RTD) of raw feed to the mill was measured using Technetium-99m adsorbed on the clinkers as a radiotracer. From the measured RTDs, solid holdup and …

Gitau W, Camberlin P, Ogallo L, Bosire E. "Trends of Intraseasonal Descriptors of Wet and Dry Spells over Equatorial Eastern Africa." International Journal of Climatology. 2018;38(3):1189-1200. AbstractRoyal Meteorological Society

Many African countries whose economies are largely based on weather/climate sensitive sectors are vulnerable to long‐term changes in weather and climate. This study is aimed at assessing whether the recent decades have observed any significant trend in the intraseasonal descriptors (ISDs) of wet and dry spells at local and sub‐regional levels at seasonal and monthly timescales over equatorial eastern Africa (EEA). Daily rainfall observations over 36 stations and spanning a period of 51 years (1962–2012) were used.

The study has expanded on previous results that showed contrasting trends on seasonal totals between the two rainfall seasons by demonstrating that this also affects the ISDs. At the local level, it was observed that during the long rainfall season, a given ISD would have a significant trend over several neighbouring locations, which was not the case during the short rainfall season. Secondly, for the short rainfall season, a given location would have significant trend in several ISDs. Finally, when a given ISD had a significant trend at seasonal timescale during the long rainfall season, the same ISD would have significant trends in the second and third months of the season and rarely in the first month. Such a feature was not observed for the short rainfall season. Binomial probability distribution assessment confirmed that the significant trends in the various ISDs during the long rainfall season did not occur by mere chance.

Gitau AK, Oyieke FA, W.R. Mukabana. "Assessment of the role played by domestic animals in jigger infection in Kandara sub-county, Kenya (case control study)." The Pan African Medical Journal. 2021;39:231.
Gitau EN, Muchohi SN, Ogutu BR, Githiga IM, Kokwaro GO. "Selective and sensitive liquid chromatographic assay of amodiaquine and desethylamodiaquine in whole blood spotted on filter paper.". 2004. Abstract

We have developed a sensitive, selective and reproducible reversed-phase HPLC method with ultraviolet detection (340 nm) for the simultaneous quantification of amodiaquine (AQ) and its major metabolite, desethylamodiaquine (AQm) in a small volume (200 microl) of whole blood spotted on filter paper. The method involves liquid-liquid extraction with diethyl ether followed by elution from a reversed-phase phenyl column with an acidic (pH 2.8) mobile phase (25 mM KH2PO4-methanol; 80:20% (v/v) +1% (v/v) triethylamine). Calibration curves in spiked whole blood were linear from 100-2500 ng/ml (r2 > or = 0.99) for AQ and 200-2500 ng/ml (r2 > or = 0.99) for AQm. The limit of detection was 5 ng for AQ and 10 ng for AQm. The relative recovery at 150 ng/ml of AQ (n = 6) was 84.0% and at 300 ng/ml of AQm the relative recovery was 74.3%. The intra-assay coefficients of variation at 150, 600 and 2250 ng/ml of AQ and 300, 600 and 2250 ng/ml of AQm were 7.7, 8.9 and 6.2% (AQ) and 10.1, 5.4 and 3.9% (AQm), respectively. The inter-assay coefficient of variation at 150, 600 and 2250 ng/ml of AQ and 300, 600 and 2250 ng/ml of AQm were 5.2, 8.1 and 6.9% (AQ) and 3.3, 2.3 and 4.6% (AQm). There was no interference from other commonly used antimalarial and antipyretic drugs (chloroquine, quinine, sulfadoxine, pyrimethamine, artesunate, acetaminophen and salicylate). The method is particularly suitable for pharmacokinetic studies in settings where facilities for storing blood/plasma samples are not available.

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