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Gichuki N. Banking Law: Cases and Materials.; Forthcoming.
Gichuki FN;, Mungai DN;, Gachene CKK. Soil and water management in semi-arid Kenya: an overview..; 2000. AbstractWebsite

This paper presents results of a study aimed at quantifying soil and water management practices and identifying major constraints and implications for future adoption of appropriate technologies. The study was conducted in the Machakos and Makueni Districts of Kenya. Approximately 83% of the farmers interviewed were using manure, while only 4% use fertilizer. 60% had fanya juu terraces on their land, while only 13% were using grass strips. The study concluded that finance is a major constraint limiting farmers' adoption of practices enhancing soil fertility and that lack of conservation practices on grazing land is of great concern. The lack of knowledge of possible benefits of soil and water management practices is noted.

Gichuki FN;, Mungai DN;. Factors affecting land use and crop production in Botswana..; 2000. AbstractWebsite

This paper looks at factors which influence land allocation and crop production patterns in Botswana, across traditional and commercial farmers. It found that, among smallholder traditional farmers, less land is used (on average 5.6 ha) and is subdivided into the growing of three major crops: sorghum, maize and beans, with more land allocated to sorghum, the main staple and more adaptable to the climate. The small amount of cultivated land is attributed to lack of capital, transport and labour. Although large areas of land are owned by commercial farmers a high percentage is left idle due to constraints such as poor marketing systems, poor storage facilities and shortage of labour.

Gichuki FN;, Mungai DN;, Gachene CKK;, Thomas DB. "Land and water management in Kenya: towards sustainable land use.".; 2000. Abstract

Preliminary findings on the effects of land use in the Masinga Dam catchment, Kenya, on the storage capacity of the reservoir are presented. Remote sensing and GIS techniques, supplemented with ground reports, were used to determine areas most susceptible to erosion. A representative catchment was then chosen for rainy season monitoring of soil loss, river suspended sediments and discharge response to rainfall. In addition, Gerlach-type traps were used to evaluate erosion rates under different crop covers and slope gradients. A sample of 200 households was interviewed about their perceptions of erosion problems on their farms. Preliminary results suggest that the major sediment-contributing areas are the densely populated and intensively cultivated foothills of the Aberdares, rather than the semi-arid lowlands directly bordering the reservoir. Poorly drained sealed and murram roads, together with footpaths, cattle tracks and gullies, act as extensions of the drainage network during storms, channelling sediment-laden runoff from bare areas around homesteads and schools directly into the river. Subsistence crops, particularly mono-cropped maize, appear to provide poor cover for a major part of the wet season.

GICHUKI MRMUCHIRI. "Gichuki Muchiri. 1969. Resistance to airflow through shelled corn. Unpublished MSc Theses. Iowa State University.". In: Oral presentation, AFRA IV (RAF/4/009) Regional Meeting on Current and Future Activities in Maintenance and Repair of Nuclear Instruments. Arusha, Tanzania: 28th February to 2nd March 1994. University of Nairobi.; 1969.
Gichuki N. "Mainstreaming the Youth in Local Governance.". In: Consultative Workshop organized by Africa Youth Trust. Nairobi; 2008.
Gichuki NN, Ndiwa T, Jackson C, Olivier H. "Status of globally threatened waterbirds in Tana delta, Kenya.". In: Third Biennial Scientific Conference, National Musuems of Kenya, Nairobi. Nairobi, Kenya ; 2011.
Gichuki FN;, Mungai DN;. Erosion scars caused by earthflows: a case study of Ol Joro Orok division, Nyandarua district.; 2000. AbstractWebsite

This paper describes earthflow features in Nyairoko sub-location of Ol Joro Orok Division, Kenya. In 1989 more than 900 earthflows were counted in Nyandarua District, most of them in Ol Joro Orok and Ol Kalou Divisions. Individual flows affected areas between a few square metres and two hectares. More than 50% of the farms in the area were affected by earthflows. Such earthflows occurred only on grazing land and on convex slopes and were usually the result of extremely slow processes. Soils in the area are mainly moderately well drained, dark reddish brown Luvisols and well-drained, red to reddish-brown Nitisols. The first visible signs were usually shallow scars along the contour, breaking up the grass vegetation. Subsequent soil movement was very gradual. According to old residents of the area some of the earthflow features had been observed as long as 60 years ago and could not be attributed to land use change. One earthflow studied in detail revealed that soil stratification impeded drainage, leading to oversaturation of the topsoil layers and that seasonal subsurface flow generally seemed to be responsible for the soil movement. No obvious triggering could be identified.

GICHUKI MRMUCHIRI. "Gichuki Muchiri et al. 1985. Animal Drawn Equipment Development in Kenya. In Agricultural Machinery Manufacturing lixcess capacity in Kenya by IFTIK-HAR AHMED and Bill Kinsey, International Labour Office, Geneve.". In: Oral presentation, AFRA IV (RAF/4/009) Regional Meeting on Current and Future Activities in Maintenance and Repair of Nuclear Instruments. Arusha, Tanzania: 28th February to 2nd March 1994. University of Nairobi.; 1985.
Gichuki N. "The Paradox in the Implementation Matrix in Capital Markets Reform in Kenya.". In: Emerging Trends in Commercial & Financial Law Workshop. KCB Leadership Centre, Karen, Nairobi; 2011.
Gichuki NN, Matagi S. "South Eastern Rift Valley Lakes of Eastern Africa.". In: Freshwater Ecosregions of Africa and Madagascar. New York: Island Press; 2005.
Gichuki JW, Opiyo R, Mugyenyi P, Namusisi K. "Healthcare providers’ level of involvement in provision of smoking cessation interventions in public health facilities in Kenya." Journal of Public Health in Africa. 2016.
Gichuki FN;, Mungai DN;. Effects of phosphorus supply on the growth and nodulation of cowpeas..; 2000. AbstractWebsite

The effects of P supply (0, 20, 40, 80, 160 and 320 kg/ha) on growth and nodulation of cowpeas (Vigna unguiculata) cv. Vita 4 and Ife Brown grown in a podzolic soil (Haplustult) was studied in a greenhouse trial. The seeds were inoculated with Bradyrhyzobium CB 756. Plants were harvested at the beginning of flowering. The number of trifoliate leaves and DM yield in both cv. increased with increasing P application. The yield of the tops of Vita 4 was maximum at 160 kg P/ha and that of Ife Brown at 320 kg P/Ha. Extractable P related linearly to the rate of applied P, and DM yield increased with increase in extractable P. Plants grown without P had fewer and smaller nodules. An increase in P from 1 to 160 kg/ha increased the number of nodules/plant from 16 to 113 in Vita 4 and from 14 to 70 in Ife Brown. Similarly, increasing P increased nodule dry weight. The P conc. of the youngest fully expanded leaf (YFEL) and in the whole plant top increased with increasing P supply in both cv. and was generally higher in the YFEL than in the whole top. A critical P conc. of 0.3 and 0.25% was found in the YFEL and the whole top, resp., for cv. Vita 4.

Gichuki CM, Gichuki NN. Wetland birds of Kenya.; 1992.Wetland birds of Kenya
GICHUKI MRMUCHIRI. "Gichuki Muchiri. 2004. Conservation tillage Equipment productivity quantified. A case study in semiarid smallholder Agriculture in Eastern Kenya. Unpublished PhD Thesis submitted for examination. University of Nairobi.". In: Oral presentation, AFRA IV (RAF/4/009) Regional Meeting on Current and Future Activities in Maintenance and Repair of Nuclear Instruments. Arusha, Tanzania: 28th February to 2nd March 1994. University of Nairobi.; 2004.
Gichuki FN;, Mungai DN;, Gachene CKK;, Thomas DB. Riverbank protection and food security..; 2000. AbstractWebsite

This paper reflects on the role of root crops (cocoyam, Colocasia esculenta or C. antiquorum) as a case study in riverbank protection and food security in Kenya. Field performance, water erosion control, ecologically friendly production and food value were studied. It is concluded that the national relevance of cocoyam cultivation lies in its role in its conservation through erosion control and soil fertility maintenance; its low energy input; its potential to supplement per capita calories through high yield per unit area; its perpetuity; its multiple nutritive value, ease of preparation and digestibility; and its industrial potential and competitive market opportunity for various end-products.

Gichuki FN;, Mungai DN;. The effect of variations in maize stover placement on maize growth and nitrogen uptake in continuous maize cropping systems in two regions of Kenya..; 2000. AbstractWebsite

Stover placement (surface mulch, incorporated or a mixture of mulch and incorporation) was compared with stover removal in the presence and absence of 50kg N fertilizer/ha in trials over two successive seasons in continuous maize cropping systems in two regions in Kenya. Stover applied at 4 tonnes DM/ha was found to have highly variable effects on maize growth and yield according to site., method of stover placement, N application and season. Relative to controls without stover, stover incorporation reduced yield by 39% in the first season, followed by yield increases of 15% in the second season. In the first season there was little or no response to N in the presence of stover. Low N uptake and N use efficiency suggested N immobilization in the incorporation treatment. Yield responses and large N uptake in the following season suggested mineralization of N immobilized in the previous season. Surface mulching at the Kabete site increased grain yields in the first season by 39% and 6% compared to stover removal without and with fertilizer, resp. In the second season, surface mulching markedly reduced yields possibly due to a combination of reduced phytotoxicity and N immobilization. At the Katumani site, stover amendments increased yields compared to removal in both seasons with incorporation results being superior to surface mulch. At this site, in both seasons, application of N reduced the effect of stover mulching and incorporation. You must log in to CAB Direct in order to view search results. If you have forgotten your log

Gichuki FN;, Mungai DN;, Gachene CKK. Some" near-farmer" research on land and water management for crop production in semi-arid Kenya..; 2000. AbstractWebsite

This paper describes a "near-farmer" applied research project working on 10 field stations scattered through the arid and semi-arid lands of Embu, Meru and Isiolo Districts of Esatern Province, Kenya. The objective of the research was to define better extension messages for resource-poor farmers to enable them to improve their land and water management techniques for improved and sustained yields. Most of the trials related to soil fertility and soil moisture, as well as trials on the use of Vetiver grass for soil conservation, control of the legume root parasite Alectra vogelii, and new introductions such as groundnuts, simsim (sesame), tubers, fodder crops and fruits.

Gichuki FN;, Mungai DN;, Gachene CKK. Residual effect of lucerne on wheat yield: report of a farm trial at Njoro, Nakuru district..; 2000. AbstractWebsite

This paper presents results from a trial in Swara Farm, Njoro, Kenya, in which a field was sown with Sorghum almum on a volcanic ash soil. Immediately after sowing, 14 strips measuring 156 m x 9 m were marked out and alternate strips were oversown with inoculated seed of lucerne cv. Hairy Peruvian. During the first year of the trial no differences were noticed in the growth of S. almum, but during the second year it grew better when associated with lucerne. After two years the field was ploughed and sown with wheat. The strips were harvested separately with a combine harvester. Mean yields after S. almum were 2,708 kg/ha and after the S.almum/lucerne mixture were 3,244 kg/ha

Gichuki FN;, Mungai DN;, Thomas DB. Development of a streamflow model for rural catchments in Kenya..; 1993. AbstractWebsite

A stream flow model was developed for use in rural catchments in Kenya. In the model the physical environment was divided into three zones: the unsaturated zone (consists of multiple hydrological response units defined by homogenous land use and soil type in which a daily soil moisture balance is maintained), shallow saturated and deep saturated zones which were modelled as regional aquifers. Rainfall and evapotranspiration were distributed according to altitude, and runoff was determined using the curve number method devised by the US Soil Conservation Service: a function of five-day antecedent precipitation. Evapotranspiration was varied according to the soil moisture content, and the weather generator allowed Monte Carol simulations over a long period. The data consisted of daily rainfall, mean daily evaporation for each month, land use/vegetation and soil type. The ARC-INFO GIS package was used to assemble the topographical, hydrological, land use/vegetation type and soil information in different layer. The model was tested on the Naro Moru catchment (172kn2) in Kenya, which has climatic conditions that vary from the glaciated peaks of Mount Kenya (5,200 m) to the semi-arid Laikipia plateau (1,800 m). The model was calibrated over a two-year period and validated over a different two-year period. A comparison of the observed and simulated stream flow showed that minimal calibration was required. The simulated stream flow compared well with the observed values for both the calibration and the validation periods (70-85% for the 10-day period) indicating that the model is appropriate for ungauged catchments.

Gichuki FN;, Mungai DN;. Hedgerows for control of soil erosion in Kabale, southwest Uganda..; 2000. AbstractWebsite

Runoff and soil loss was studied on steep terraced slopes containing various combinations of lines of Grevillea robusta, hedgerows of Calliandra calothyrsus and strips of Pennisetum purpureum in Kabale, southwest Uganda. A factorial design, replicated three times, included three levels of intra-row spacing (0, 3 and 5m) of Grevillea spp. and three understorey types (none, Pennisetum and Calliandra spp). The understorey and Grevillea were interplanted along a contour in the middle of the terrace parallel to the two adjacent risers. Results indicate that when contour lines of trees are on fallow ground there is little or possibly a negative effect in controlling soil and water loss. When contour lines are on steep cultivated terraces they have a significant effect in reducing losses. The understoreys appear to filter out much of the sediment from the runoff, holding it in or above the contour line of the vegetation. The potential for using contour lines of Pennisetum and Calliandra for controlling soil and water loss is discussed.

Gichuki FN;, Gachene CKK, Mungai DN;. Minimizing hydrological impacts of smallholder drainage development.; 2000. AbstractWebsite

A review of available literature on the hydrologic impacts of drainage is presented and management practices that reduce such impacts are identified. Factors that influence the impact of drainage include land use, soil type, drainage density, type and condition of the drains, size and duration of the storm, and extent and location of the drainage. Suggested options for minimising impacts include: appropriate land use (fish ponds, duck farming, harvesting natural products, dry season grazing or cultivation); controlled drainage through use of shallow drains, drainage for growing water-loving plants, land preparation (hilling, cambered beds), and blocking drains at the end of the rains; and water storage (dams along the river or farm ponds).

Gichuki, FN; Mungai DN;, Gachene CKK, Gichuki FN;. A participatory route towards conservation farming for better land husbandry..; 2000.Website
Gichuki FN, Gachene CKK. Biological and water-harvesting measures for gully control.; 2000. AbstractWebsite

The Arpolo gullying control project in the West Pokot Region of Kenya is described. This is an example of conservation work done to protect the Arpolo dispensary which cost >KES350,000 to put up and serves about 3,000 people and is threatened by a fast-growing gully. The initial proposal for a concrete wall in the first phase of implementation was not feasible since it would be undermined during the rains. The alternative was to plan, design and apply water-harvesting methods and implement biological measures that would reduce the erosive energy of the surface runoff. The design of the water-harvesting structures is shown. The success of the project shows that land and water management requires skillful planning and design, especially where soils are vulnerable to erosion. The physical and chemical properties of the soils in the area are described. Given proper hydraulic designs, water-harvesting measures are still a reliable means of soil conservation.

Gichuki FN;, Mungai DN;, Gachene CKK. Soil and water management in semi-arid Kenya: an overview..; 2000. AbstractWebsite

This paper presents results of a study aimed at quantifying soil and water management practices and identifying major constraints and implications for future adoption of appropriate technologies. The study was conducted in the Machakos and Makueni Districts of Kenya. Approximately 83% of the farmers interviewed were using manure, while only 4% use fertilizer. 60% had fanya juu terraces on their land, while only 13% were using grass strips. The study concluded that finance is a major constraint limiting farmers' adoption of practices enhancing soil fertility and that lack of conservation practices on grazing land is of great concern. The lack of knowledge of possible benefits of soil and water management practices is noted.

GICHUNGE DRHEZEKIAH. "Gichunge, H. and Aligula, M.E.(2003): .". In: Politics and Political Science (Online Publication), Vol. 43, Number 1, January 2010. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 2003. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
GICHUNGE DRHEZEKIAH. "Gichunge H. (1993): International Contracting for the Construction Industry in changing times. A paper presented in A.A.K Professional Practice Conference on 29th .". In: Nairobi Journal of Management. Volume 6, PP 117-145. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 1993. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
GICHUNGE DRHEZEKIAH. "Mbeche, I.M. and Gichunge, H. (2003): Risk Management in Building projects: An Analysis of time and Cost Risks.". In: Nairobi Journal of Management. Volume 6, PP 117-145. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 2003. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
GICHUNGE DRHEZEKIAH. "Gichunge, H. (1991): Value Engineering and Constructibility Improvement Studies. A Paper presented in a workshop on Project Management, Construction and Architecture, FADD, University of Nairobi.". In: Nairobi Journal of Management. Volume 6, PP 117-145. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 1991. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
GICHUNGE DRHEZEKIAH. "Olima, W.H.A and Gichunge, H. Emerging Environmental concerns in Nairobi: The Case of East African Towns in transition, GLCA/UON Symposium, from 17th -19th June 2002, Heritage Voyager Hotel in Mombasa.". In: Nairobi Journal of Management. Volume 6, PP 117-145. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 2002. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
GICHUNGE DRHEZEKIAH. "Factors that contribute to cost of provision of low cost housing in Nairobi, Kenya. Published conference proceedings on Low Cost Housing I, CMTSI, PP 1-12, International Conference on Spatial Information for Sustainable Development, Nairobi, Kenya, 2-5th .". In: Nairobi Journal of Management. Volume 6, PP 117-145. GIGA German Institute of Global and Area Studies, Hamburg, July 2009; 2001. Abstract
This integrative review on the teaching of reading in Kenyan primary schools provides a foundation for the growing movement there to improve reading education. In gathering sources for this review, we took an inclusive historical stance. Thus, we did not dismiss research reports that lacked traditional indicators of quality such as being published in peer-reviewed journals. We used multiple methods to find relevant research and associated documents, including two trips to Kenya. The review is organized by six topics: (a) language of instruction, (b) reading instruction, (c) reading materials, (d) reading culture, (e) assessment, and (f) teacher development. The review concludes with six proposals for policymakers, educational researchers, and teacher educators for the development of reading instruction based on what we learned in reviewing the literature. The first proposals are intended specifically to address the teaching of reading in Kenya, but they may be relevant to other sub-Saharan nations. The final proposal encourages others to conduct similar reviews to make possible a handbook of reading in Africa.
Gichure, J. N. KMICNPM. "Standardization of cut size and pre-drying time of beef to mainstream pastoral processing in Kenya’s meat industry." Pastoralism: Research, Policy and Practice. 2017;7:1-7.
Gichure, N.G., Wahome, R.G., Njage, P.K., Karuri, H. W., Nzuma, M.J., Karantininis, K. "Factors influencing extent of traceability along organic fresh produce value chains: case of kale in Nairobi, Kenya." Organic Agriculture. 2017;7(3):293-302.
Gichuru EK;, Combes MC;, Mutitu EW;, Ngugi ECK;, Omondi CO;, Bertrand B;, Lashermes P. Towards the development of sequence based markers for resistance to coffee berry disease (Colletotrichum kahawae).; 2009. AbstractWebsite

Coffee Berry Disease which affects green Arabica coffee (Coffea arabica) berries is caused by the fungus Colletotrichum kahawae and is a major problem in Arabica coffee production in African countries. Breeding for resistance to this disease is therefore to a major priority in these countries avoid intensive chemical usage for its control. Recently, microsatellite and Amplified Fragment Length Polymorphisms (AFLP) markers for a gene conferring resistance to the disease were identified and mapped onto the chromosomal region carrying the gene. To improve the repeatability of the AFLP markers, four of the marker bands were selected for cloning and sequencing to facilitate specific primers to be designed. Three of the resultant primers did not amplify products that exhibited polymorphism characteristic of the parent AFLP bands; but one primer pair amplified a product that dominantly identified the presence of the parent AFLP marker at an optimum temperature of 62°C followed by electrophoresis in agarose. The reliability of the designed primers was confirmed by analysis in 95 plants from a F2 population previously used to map the chromosomal fragment carrying the resistance. The importance of the results in enhancing the utility of the parent AFLP marker in relation to analytical costs and position on the chromosomal fragment is discussed.

Gichuru L, Derera J, Njoroge K. "The incidence of diseases and other constraints found in small-scale maize cropping systems of Kenya-midlands.". In: Annual Joint Meeting of the National Association of Plant Breeders (NAPB), and the Plant Breeding Coordinating Committee PBCC).; 2012.
Gichuru L, Ininda J, Njoroge K. "Maize streak virus (MSV) disease expression in F1 hybrids of diverse genotypes.". In: 10th KARI biennial conference. Nairobi, Kenya ; 2007.
kariuki james gichuru. "The gender implications of men’s shift from cash-crop farming to dairy farming in Central Kenya." International Journal of Social Sciences and Entrepreneurship. 2013;1(5):631-646.
Gichuyia LN. "INDOOR OVERHEATING RISK ANALYSIS OF OFFICE BUILDINGS IN NAI- ROBI IN A CHANGING CLIMATE.". In: Annual Eastern Africa Architecture Workshop and Exhibition. ADD Building - University of Nairobi; 2019.
Gichuyia LN. BOOSTING INTERCON- TINENTAL RELATIONS _ LESSONS FROM BUILDING PHYSICS. Wilhelm Kempff house- Casa Orfeo, Positano -Italy,; 2019.
Gichuyia LN. "LESSONS LEARNT FROM THERMAL DATA-LOGGING OF BUILDINGS IN NAIROBI OVER THE YEARS; HIGHLIGHT- ING THE DEMAND FUNCTIONS FOR DECI- SION-SUPPORT.". In: Annual Eastern Africa Architecture Workshop and Exhibition. ADD Building - University of Nairobi; 2019.
Gichuyia LN. "NAIROBI CITY MARKET: AN ELASTIC ARCHITECTURE AND URBAN DE- SIGN EXPERIENCE ACROSS TIME AND SPACE.". In: NAIROBI CITY MARKET: AN ELASTIC ARCHITECTURE AND URBAN DE- SIGN EXPERIENCE ACROSS TIME AND SPACE. Leuven, Belgium: Leuven University Press ; 2019.
Gichuyia LN. INDOOR OVERHEAT- ING RISK: A FRAMEWORK FOR TEMPORAL BUILDING ADAPTATION DECISION-MAKING. Cambridge, London: University of Cambridge - https://doi.org/10.17863/CAM.17146; 2017.
Gichuyia LN. "THE IMPACT OF CLIMATE CHANGE ON THE INDOOR OVERHEATING RISK LANDSCAPE OF NAIROB.". In: In Proceedings of the Annual Architecture and Engineering Conference - Business opportunities in Energy, Manufacturing, Infrastructural and Environmental Research. School of Engineering, University of Nairobi, Kenya; 2019.
Gichuyia LN, Madette E. "OCHA: THE EAST AFRICAN COUNTRYSIDE FORMS.". In: OCHA: THE EAST AFRICAN COUNTRYSIDE FORMS. Rotterdam, Netherlands: OMA/AMO Press; 2019.
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 EW, p o Oduor OS, Kanyanjua SM, Keter JKA. "Phosphate sorption by some kenyan soils as evaluated by the langmuir and freundlich adsorption equations.". 2000. Abstract

The sorption of added inorganic phosphate (P) by eight soils which varied appreciably in their ability to sorb P was evaluated using the Langmuir and Freundlich adsorption equations. When the sorption data were plotted according to the conven¬tional Langmuir and linear Freundlich equations, linear relationships were obtained. Regression analysis was used to compute the straight lines obtained. The Freundlich equations gave significantly to highly significantly correlation coefficients (r2 = 0.509 - 0.972) in all the soils tested while the Langmuir equation was non-sig¬nificant in the highest and lowest sorbing soils (r2 0.004 and 0.453 respectively) but was highly to very highly significant in the other soils (r2 = 0.816 - 0.988). The Freundlich equation was, therefore, ade¬quate in describing the sorption data in all the soils tested but with varying precision as shown by the different correlation coeffi¬cients. A comparison of the two equations indicated that Freundlich equation gives the best fit in majority of soils and would, therefore, be recommended for estimating the P-sorption characteristic of soils tested in this work.

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 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 Initiatives .; 2014.
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.
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.

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).

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.

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.

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 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. "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. "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 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., 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. "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. "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., 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.
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 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 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., 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. "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. "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. "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. "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 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., 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 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. "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. "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. (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 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 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 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 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.
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. Current Research Projects. Nairobi: Dept Vet Pathology; 2014.current_research-.pdf
Gitao CG, Mbindyo C, Bebora L. "Dairy Goat Milk Hygiene: Analyses in Mt Kenya Region.". 2014. Abstract
n/a
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 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 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 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., 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 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, 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, 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, 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 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. 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 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, 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 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 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
n/a
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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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 OJJ &. Business Law. Nairobi: Focus Books; 2010.
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, M DRMUNYUASJ. "J. K. Wabacha, J.M. Maribei, A.G. Thaiya, S.J.M. Munyua, D.N. Karanja and E.M. Njoroge(2000). Progressive atrophic rhinitis in a medium scale pig farm in Kiambu, Kenya. J. S. Afr. Vet. Ass. 71 (2): 122-124.". In: Journal of South Africa Veterinary Association. 71(2): 122-124. J. S. Afr. Vet. Ass.; 2000. 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, 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. "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 T;, McDermott JJ;, Waltner-Toews D;, Gathuma JM;, Kang EK;, Kimani VW;, Kilungo, J K;, Muni RK;, Mwangi JM;, Otieno GO. "Agro-ecosystems, natural resources management and human health related research in East Africa."; 1989. Abstract

The paper briefly describes the application of agro-ecosystem health framework for characterization of an agro-ecosystem in central Kenya, and identification of the indications of its health. The lessons learnt from the application are briefly discussed.

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.
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, 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. (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 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. "J.K. WABACHA, C.M.M. Mulei, N.P. Gitonga, M.J. Njenga, A.G. Thaiyah and J. Nduhiu. An outbreak of unusual form of acute ovine dermatophilosis in a mixed farming enterprise in Kenya. Bull. Anim. Hlth. Prod. Afr. 54:144-147.". In: Faculty of Veterinary Medicine Biennial Scientific Conference, Nairobi, 6th . Bull. Anim. Hlth. Prod. Afr.; 2006. 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 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 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 GK;, Aleri JW;, Mbuthia PG;, Mulei C. "Major causes of calf mortality in peri-urban area of Nairobi, Kenya."; 2010.
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. "Acute toxicity of Nicandra physaloides (L) Gaertn in cattle and mice. Muthee, J.K., Mbaria, J.M., Thaiya, A.G. and Gakuya, D.W.". In: kenya veterinarian 33: 1-6. kenya veterinarian 33: 1-6; 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., 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 CMW, Gor SO. "Measuring Factor Productivity of the Banking Sector in Kenya." OIDA International Journal of Sustainable Development. 2011;2(12):1-18.
Gitau OJJ &. Business Law. Nairobi: Focus Books; 2010.
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 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, A.N., K. N. Technical Manual : Soil and Water Conservation - ISBN: 978 9966 1533 8 8. Nairobi: Sustainable Agriculture Information Initiative; 2010.

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