Publications

Found 2273 results

Sort by: Author [ Title  (Asc)] Type Year
Filters: First Letter Of Title is O  [Clear All Filters]
A B C D E F G H I J K L M N [O] P Q R S T U V W X Y Z   [Show ALL]
O
ONYAMBU DRKWAMBOKACALLEN, MATHENGE DRMURIITHIIAN. "Onyambu CK, Muriithi IM, Ngare SM. Cerebral Venous Sinus Thrombosis: A Report of Two Cases. EAMJ.2010;87:220-224." EAST AFRICAN MEDICAL JOURNAL. 2010;87(5):220-224. AbstractWebsite

Cerebral venous sinus thrombosis is an uncommon yet potentially life threatening condition which is often under-diagnosed or misdiagnosed because of the variability of the clinical signs and symptoms. The imaging findings are often subtle thus the need for a high index of suspicion. The superior sagittal and transverse sinuses are the most frequently involved. The correct diagnosis of cerebral venous thrombosis relies on neuroimaging studies. The two cases reported highlight the fact that the radiologist may be the first clinician to suspect and diagnose this condition. This ultimately affects prognosis as early diagnosis and treatment reduces morbidity and mortality.

WANJIRU DRNGUGIROSE. "Onyancha C.; Are foreign exchange and stock markets related? An empirical analysis of the Kenyan case, 1998, University of Nairobi.". In: Paris 2011 World Cup in Paris, France. The Icfai University Journal of Architecture, Vol. II No.1, February 2010; 1998. Abstract
In contrast with mammalian cells, little is known about the control of Ca2+ entry into primitive protozoans. Here we report that Ca2+ influx in pathogenic Trypanosoma brucei can be regulated by phospholipase A2 (PLA2) and the subsequent release of arachidonic acid (AA). Several PLA2 inhibitors blocked Ca2+ entry; 3-(4-octadecyl)-benzoylacrylic acid (OBAA; IC50 0.4+/-0.1 microM) was the most potent. We identified in live trypanosomes PLA2 activity that was sensitive to OBAA and could be stimulated by Ca2+, suggesting the presence of positive feedback control. The cell-associated PLA2 activity was able to release [14C]AA from labelled phospholipid substrates. Exogenous AA (5-50 microM) also initiated Ca2+ entry in a manner that was inhibited by the Ca2+ antagonist La3+ (100 microM). Ca2+ entry did not depend on AA metabolism or protein kinase activation. The cell response was specific for AA, and fatty acids with greater saturation than tetraeicosanoic acid (AA) or with chain lengths less than C20 exhibited greatly diminished ability to initiate Ca2+ influx. Myristate and palmitate inhibited PLA2 activity and also inhibited Ca2+ influx. Overall, these results demonstrate that Ca2+ entry into T. brucei can result from phospholipid hydrolysis and the release of eicosanoic acids.
OMOLO PROFWANGOEMMANUEL. "Onyango D.W., Wango E.O. and Werner G.(2001). Epididymal epithelial cell involution following a single intraperitoneal administration it and it it paid of ethane dimethanesulphonate (EDS) in the goat (Capra hircus) Toxicol. Appl. Pharmacol. 175(1): 19-27.". In: Biennial Conference. Faculty of Vet. Medicine. EM Ngatia, LW Gathece, FG Macigo, TK Mulli, LN Mutara, EG Wagaiyu.; 2001. Abstract

SUMMARY LIII)' lIIorpllOlogiClI changcs ill the goat ,csris after:. sillgle illlraperilOlieal injec,ioll of ethalle ,lillie' I.:lIIeslll"llOnarc (EI )S) werc investigatcd mint; (1Orh liglH alld deCll'On microscopy. The (olllpolind was ;almillistered at two dose Icvels: 75 mgll

OMOLO PROFWANGOEMMANUEL. "Onyango D.W., Wango E.O., Odongo H., Mugweru J and Okindo E.(1996). Effects of heptachlor on plasma LH, testosterone and cortisol and testicular structure.". In: First Pan African Conference on Biochemistry and Molecular Biology, Nairobi, Kenya. Abstr. B-31. EM Ngatia, LW Gathece, FG Macigo, TK Mulli, LN Mutara, EG Wagaiyu.; 1996. Abstract

SUMMARY LIII)' lIIorpllOlogiClI changcs ill the goat ,csris after:. sillgle illlraperilOlieal injec,ioll of ethalle ,lillie' I.:lIIeslll"llOnarc (EI )S) werc investigatcd mint; (1Orh liglH alld deCll'On microscopy. The (olllpolind was ;almillistered at two dose Icvels: 75 mgll

OMOLO PROFWANGOEMMANUEL. "Onyango D.W., Wango E.O., Odongo H., Mugweru J. and Okindo E.(1998). Effects of heptachlor on rat plasma LH, testosterone and cortisol levels, and testicular structure.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology (FASBMB), pp195-198. EM Ngatia, LW Gathece, FG Macigo, TK Mulli, LN Mutara, EG Wagaiyu.; 1998. Abstract

SUMMARY LIII)' lIIorpllOlogiClI changcs ill the goat ,csris after:. sillgle illlraperilOlieal injec,ioll of ethalle ,lillie' I.:lIIeslll"llOnarc (EI )S) werc investigatcd mint; (1Orh liglH alld deCll'On microscopy. The (olllpolind was ;almillistered at two dose Icvels: 75 mgll

OMOLO PROFWANGOEMMANUEL. "Onyango D.W., Wango E.O., Oduor Okelo D. and Werner G (2001).Early testicular response to intraperitoneal administration of ethane dimethanesulphonate (EDS) in the goat (Capra hircus). J. Submicrosc.Cytol. Path. 33 (1-2), 117-124.". In: Biennial Conference. Faculty of Vet. Medicine. EM Ngatia, LW Gathece, FG Macigo, TK Mulli, LN Mutara, EG Wagaiyu.; 2001. Abstract
Early morphological changes in the goat testis after a single intraperitoneal injection of ethane dimethanesulphonate (EDS) were investigated using both light and electron microscopy. The compound was administered at two dose levels: 75 mg/kg and 25 mg/kg. While the former resulted in some deaths due to toxicity, the latter had no noticeable toxic effects on the animals. The testicular effects at both dose levels were similar. Six (6) days post-treatment, Leydig cells were refractory to EDS challenge but there was a marked disruption of spermatogenesis. These Leydig cells exhibited ovoid or irregularly round nuclei, abundant cytoplasm containing spherical, ovoid or elongate mitochondria and a preponderance of smooth endoplasmic reticulum typical of the normal cells. Lipid droplets were rare. In the seminiferous tubules germ and Sertoli cell degeneration was observed. Changes in the germ cells included: spermatogonial degeneration, condensed chromatin in leptotene spermatocytes and failure of chromatin re-organization resulting in the formation of clumps in the cells at the telophase stage of cell division (stage 4 of the seminiferous cycle).The nuclear envelope of primary spermatocytes showed marked irregularity and there was an overall reduction in cell size. There was peripheral re-distribution of chromatin in developing spermatids of stages 1, 2 and 5, often resulting in thick margination along the nucleolemma and leaving a pale nucleoplasm. An accompanying retention of maturation phase spermatids in stage 2 tubules was also observed. Sertoli cells exhibited extensive accumulation of intracytoplasmic vesicles, obscuring the rest of the organelles. Intercellular vacuoles also occurred within the epithelium. The results suggest that while EDS does not have any effect on goat Leydig cells, it causes severe disruption of the spermatogenic process. Furthermore, it is concluded from the results that the optimum dose in this species is 25 mg/kg
OMOLO PROFWANGOEMMANUEL. "Onyango D.W., Wango E.O., Owiti G.E.O., Oduor Okelo D. and Werner G. (2000). Morphological characterisation of the seminiferous cycle in the goat (Capra hircus): a histological and ultra structural study.Ann. Anat.,182(3), 235-241.". In: 5th Society of Neuroscientists of Africa (SONA) Conference, Nairobi, Kenya, 23rd-27th April. EM Ngatia, LW Gathece, FG Macigo, TK Mulli, LN Mutara, EG Wagaiyu.; 2000. Abstract

SUMMARY LIII)' lIIorpllOlogiClI changcs ill the goat ,csris after:. sillgle illlraperilOlieal injec,ioll of ethalle ,lillie' I.:lIIeslll"llOnarc (EI )S) werc investigatcd mint; (1Orh liglH alld deCll'On microscopy. The (olllpolind was ;almillistered at two dose Icvels: 75 mgll

M. PROFKITONYIJOSEPHK. "Onyango F.E., Wafula E.M., Kitonyi J.M.K et al. Hypoxaemia in young Kenyan children with acute lower respiratory infection.BMJ. 1993 Mar 6;306(6878):612-5.". In: BMJ. 1993 Mar 6;306(6878):612-5. Comment in: BMJ. 1993 May 15;306(6888):1342. Vaccine 26:2788- 2795; 1993. Abstract

OBJECTIVES–To determine the prevalence, clinical correlates, and outcome of hypoxaemia in acutely ill children with respiratory symptoms. DESIGN–Prospective observational study. SETTING–Paediatric casualty ward of a referral hospital at 1670 m altitude in Nairobi, Kenya. SUBJECTS–256 Infants and children under 3 years of age with symptoms of respiratory infection. MAIN OUTCOME MEASURES–Prevalence of hypoxaemia, defined as arterial oxygen saturation < 90% determined by pulse oximetry, and condition of patient on the fifth day after admission. RESULTS–Over half (151) of the children were hypoxaemic, and short term mortality was 4.3 times greater in these children. In contrast, the relative risk of a fatal outcome in children with radiographic pneumonia was only 1.03 times that of children without radiographic pneumonia. A logistic regression model showed that in 3-11 month old infants a respiratory rate > or = 70/min, grunting, and retractions were the best independent clinical signs for the prediction of hypoxaemia. In the older children a respiratory rate of > or = 60/min was the single best clinical predictor of hypoxaemia. The presence of hypoxaemia predicted radiographic pneumonia with a sensitivity of 71% and specificity of 55%. CONCLUSIONS–Over half the children presenting to this referral hospital with respiratory symptoms were hypoxaemic. A group of specific clinical signs seem useful in predicting hypoxaemia. The clear association of hypoxaemia with mortality suggests that the detection and effective treatment of hypoxaemia are important aspects of the clinical management of acute infections of the lower respiratory tract in children in hospital in developing regions. PIP: In 1989, pediatricians followed 256 children 7 days to 36 months old with symptoms of respiratory infection at Kenyatta National Hospital (1670 m altitude) in Nairobi, Kenya. The symptoms were serious enough to warrant hospital admission for 209 of these children. The most common clinical diagnoses were pneumonia (53%) and bronchiolitis (33%). 59% of the children admitted to the hospital were hypoxemic (arterial oxygen saturation or + to 90%). 10% of all admitted children died. 90.4% of them were hypoxemic with arterial oxygen saturations ranging from 40-88%. Children with hypoxemia were 4.3 times more apt to die within 5 days than those with no hypoxemia (p = .02). On the other hand, children with radiographic pneumonia had a relative risk of short-term mortality of only 1.03. Hypoxemia on admission predicted short-term mortality with 90% sensitivity and 34% specificity. It predicted pneumonia with 71% sensitivity and 55% specificity (p .0001). Children who lived for at least 5 days had arterial oxygen saturations ranging from 41-98. Even though all of the children with clinically evident cyanosis were less than a year old, 89% of the hypoxemic infants less than 1 year old did not exhibit cyanosis. Mothers' reports of blueness in newborns and infants less than 2 months was the best predictor of hypoxemia (62% accuracy; p .05). For children 3-11 months old, the best predictors of hypoxemia, with an accuracy of 70%, were a respiratory rate of at least 70/minute (odds ratio [OR] 2.6; p .001). For children at least 12 months old, the sole best predictor was a respiratory rate of at least 60/minute (70% accuracy; OR 5.1; p .01). This study should be followed by well-designed studies of the clinical effectiveness of proper treatment with oxygen in preventing mortality in hypoxemic infants and children.

O. PROFNDINYA-ACHOLAJ. "Onyango FE, Ndinya-Achola J, Orinda VA, Musoke RN.Lancefield group B beta-haemolytic streptococcal infections in the newborn at Kenyatta National Hospital (K.N.H.).East Afr Med J. 1984 May;61(5):376-81.". In: East Afr Med J. 1984 May;61(5):376-81. IBIMA Publishing; 1984. Abstract
Routine procedures used to isolate Haemophilus ducreyi in a busy laboratory are reported. Identification was based on colony morphology and nutritional and biochemical properties of 120 fresh isolates of H. ducreyi. These isolates grew very well on Gonococcal Agar and Mueller-Hinton Agar incubated at 34 degrees C in candle extinction jars containing moistened filter paper. Colonies varied in size, giving a polymorphic appearance. They were smooth, dome-shaped, and buff-yellow to grey in colour, and measured 2 mm in diameter. They could be pushed intact across the agar surface. By microscopic examination of gram-stained smears the isolates were gram-negative coccobacilli arranged in short chains, clumps or whorls and occasionally in typical "rail track" arrangements. Individual bacteria showed bipolar staining. Colonies autoagglutinated in saline. All strains were catalase-negative and did not produce indole or H2S. They were oxidase- and beta-lactamase positive and required X but not V factor for growth. Now that reliable techniques have been developed and characteristics established it is possible for most clinical laboratories to isolate and identify this organism from most patients with chancroid.
O. PROFNDINYA-ACHOLAJ. "Onyango FE, Ndinya-Achola JO, Orinda V, Musoke R. Lancefield group B Beta haemolytic Streptococcal infection in the Newborn unit at Kenyatta National Hospital. E.A. Med. J. Vol. 61: 376 - 382, 1984.". In: E.A. Med. J. Vol. 61: 376 - 382, 1984. IBIMA Publishing; 1984. Abstract
Routine procedures used to isolate Haemophilus ducreyi in a busy laboratory are reported. Identification was based on colony morphology and nutritional and biochemical properties of 120 fresh isolates of H. ducreyi. These isolates grew very well on Gonococcal Agar and Mueller-Hinton Agar incubated at 34 degrees C in candle extinction jars containing moistened filter paper. Colonies varied in size, giving a polymorphic appearance. They were smooth, dome-shaped, and buff-yellow to grey in colour, and measured 2 mm in diameter. They could be pushed intact across the agar surface. By microscopic examination of gram-stained smears the isolates were gram-negative coccobacilli arranged in short chains, clumps or whorls and occasionally in typical "rail track" arrangements. Individual bacteria showed bipolar staining. Colonies autoagglutinated in saline. All strains were catalase-negative and did not produce indole or H2S. They were oxidase- and beta-lactamase positive and required X but not V factor for growth. Now that reliable techniques have been developed and characteristics established it is possible for most clinical laboratories to isolate and identify this organism from most patients with chancroid.
FREDRICK DRONYANGOJOHN. "Onyango J F, Vilembwa A, Awange D O, Wakoli KA, Dimba E A: Squamous cell carcinoma arising in a dentigerous cyst lining: a case report and literature review, JMOSI, 2008; 7: 478 .". In: a case report and literature review, JMOSI, 2008; 7: 478 . University of Nairobi Press; 2008. Abstract
Mefloquine pharmacokinetics were studied in Kenyan African normal volunteers and in patients with severe acute attack of Plasmodium falciparum malaria. Peak concentrations were achieved in both groups at 20-24 hours. The mean half-life of elimination was 385 +/- 150 hours (mean +/- SD) in normal subjects while in severe malaria it was 493 +/- 215 hours which was significantly longer (P less than or equal to 0.001). The volume of distribution was significantly smaller in severe malaria where it was 30.76 +/- 10.50 l/kg (mean +/- SD) while in the normal subjects it was 40.90 +/- 20.70 l/kg (mean +/- SD) (P less than or equal to 0.001). The total body clearance in severe malaria was 3.75 +/- 1.51 l/h (mean +/- SD). This was significantly lower than in the normal subjects where it was 5.15 +/- 1.50 l/h (mean +/- SD) (P less than or equal to 0.001).
M DRWAKIAGAJOHN, M DRWAKIAGAJOHN. "Onyango J. F., Awange D.O., and Wakiaga, J.M.: Oral Tumours and Tumour-like conditions in Kenya: I Histological distribution. East African Medical Journal 72: 560-563, 1995.". In: East African Medical Journal 72: 560-563, 1995. University of Nairobi Press; 1995. Abstract

A histological analysis of 3141 cases of oral tumours and tumour-like lesions diagnosed at Kenyatta National Hospital between 1978 and 1992 has been carried out. Squamous cell carcinoma, salivary gland tumours and lymphoid tumours form the majority of lesions. In general, the histological distribution of the oral tumours do not differ significantly from those reported in non African series save for the Burkitt's lymphoma.

K DRKAYIMAJOSHUA. "Onyango J. F., Kayima J. K. and Owen W. O. Rhinocerebral mucormycosis: case report East African Medical Journal, 79(7): 390-393; 2002.". In: East African Medical Journal, 79(7): 390-393; 2002. Ochieng P. O., McLigeyo S. O., Amayo E. O., Kayima J. K. and Omonge E. O.; 2002. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
M DRWAKIAGAJOHN, M DRWAKIAGAJOHN. "Onyango J.F.,Awange D.O. and Wakiaga J.M.: Oral Tumours and Tumourlike conditions in Kenya: II Age, Sex and Site distribution. East African Medical Journal, 72: 568-576, 1995.". In: East African Medical Journal, 72: 568-576. University of Nairobi Press; 1995. Abstract
This paper presents the age, sex and site distribution of oral tumours and tumour like conditions in Kenya. It confirms some important points. First, there is an overall lower mean age for oral tumours in African series compared to non African series. Secondly, sex bias in the distribution of oral tumours is less marked for most tumours in Africans. Thirdly, there is difference in site distribution and oral tumours between Africans and non-African populations.
FREDRICK DRONYANGOJOHN. "Onyango JF, Awange DO, Njiru A, Macharia IM. Pattern of occurrence of head and neck cancer presenting at Kenyatta National Hospital, Nairobi.East Afr Med J. 2006 May;83(5):288-91.". In: East Afr Med J. 2006 May;83(5):288-91. University of Nairobi Press; 2006. Abstract
BACKGROUND: Currently there is a dearth of data on the pattern of occurrence of head and neck cancers in Kenya. OBJECTIVE: To provide a comprehensive analysis of the pattern of occurrence of head and neck cancers in a Kenyan population. DESIGN: Retrospective hospital-based descriptive study. SETTING: Kenyatta National Hospital, Nairobi. RESULT: A total of 793 cases were recorded consisting of 507 male and 286 female (M: F = 2:1). Most of the lesions arose from the upper aerodigestive pathway. The larynx was the most common site for aerodigestive malignancies. This was followed in order of frequency, by the tongue, the mouth, and the nasopharynx. Outside the aerodigestive pathway the eye was the most commonly affected site followed by the thyroid. Squamous cell carcinoma was the most common malignancy. Sarcomas were typically rare. Gender and age distribution showed an overall male preponderance and a wide age range. However, specific tumour sites and tumour types showed varying patterns of gender and age distribution. CONCLUSION: This study confirms the relative prominence of laryngeal, oral and nasopharyngeal cancers in the African population. It is, however, at variance with other African studies regarding the relative frequency of nasal and paranasal cancers.
MUTHURE PROFMACHARIAISAAC. "Onyango JF, Awange DO, Njiru A, Macharia IM.Pattern of occurrence of head and neck cancer presenting at Kenyatta National Hospital, Nairobi.East Afr Med J. 2006 May;83(5):288-91.". In: East Afr Med J. 2006 May;83(5):288-91. University of Nairobi Case, in the proceedings of the IST-Africa 2008 Conference; Windhoek, Namibia; 2006. Abstract
BACKGROUND: Currently there is a dearth of data on the pattern of occurrence of head and neck cancers in Kenya. OBJECTIVE: To provide a comprehensive analysis of the pattern of occurrence of head and neck cancers in a Kenyan population. DESIGN: Retrospective hospital-based descriptive study. SETTING: Kenyatta National Hospital, Nairobi. RESULT: A total of 793 cases were recorded consisting of 507 male and 286 female (M: F = 2:1). Most of the lesions arose from the upper aerodigestive pathway. The larynx was the most common site for aerodigestive malignancies. This was followed in order of frequency, by the tongue, the mouth, and the nasopharynx. Outside the aerodigestive pathway the eye was the most commonly affected site followed by the thyroid. Squamous cell carcinoma was the most common malignancy. Sarcomas were typically rare. Gender and age distribution showed an overall male preponderance and a wide age range. However, specific tumour sites and tumour types showed varying patterns of gender and age distribution. CONCLUSION: This study confirms the relative prominence of laryngeal, oral and nasopharyngeal cancers in the African population. It is, however, at variance with other African studies regarding the relative frequency of nasal and paranasal cancers.
M DRWAKIAGAJOHN. "Onyango JF, Awange DO, Wakiaga JM.Oral tumours and tumour-like conditions in Kenya: II. Age, sex and site distribution. East Afr Med J. 1995 Sep;72(9):568-76.". In: East Afr Med J. 1995 Sep;72(9):568-76. University of Nairobi Press; 1995. Abstract
This paper presents the age, sex and site distribution of oral tumours and tumour like conditions in Kenya. It confirms some important points. First, there is an overall lower mean age for oral tumours in African series compared to non African series. Secondly, sex bias in the distribution of oral tumours is less marked for most tumours in Africans. Thirdly, there is difference in site distribution and oral tumours between Africans and non-African populations.
FREDRICK DRONYANGOJOHN. "Onyango JF, Awange DO, Wakiaga JM.Oral tumours and tumour-like conditions in Kenya: II. Age, sex and site distribution.East Afr Med J. 1995 Sep;72(9):568-76.". In: East Afr Med J. 1995 Sep;72(9):568-76. University of Nairobi Press; 1995. Abstract
This paper presents the age, sex and site distribution of oral tumours and tumour like conditions in Kenya. It confirms some important points. First, there is an overall lower mean age for oral tumours in African series compared to non African series. Secondly, sex bias in the distribution of oral tumours is less marked for most tumours in Africans. Thirdly, there is difference in site distribution and oral tumours between Africans and non-African populations.
FREDRICK DRONYANGOJOHN. "Onyango JF, Awange DO.Ossifying Fibroma of the Jaws: A case report and review of literature.East Afr Med J. 1991 Aug;68(8):661-7.". In: East Afr Med J. 1991 Aug;68(8):661-7. University of Nairobi Press; 1991. Abstract
This communication presents the first case report of ossifying fibroma of the jaw from Kenya and reviews the literature including the available published case reports from Africa. The relationship between ossifying fibroma and other related benign fibro-osseous lesion of the jaws is briefly discussed. Intensified research work on this condition in Africans is called for so that more cases should be published since it is reportedly more common in black race. The majority of the African cases are generally reported in advanced stages indicating neglect or delay in seeking for medical help. Since ossifying fibroma is a well encapsulated and expansile benign bone neoplasm, surgical enucleation appears to be the treatment of choice; recurrence is rare.
FREDRICK DRONYANGOJOHN. "Onyango JF, Kayima JK, Owen WO.Rhinocerebral mucormycosis: case report.East Afr Med J. 2002 Jul;79(7):390-3.". In: East Afr Med J. 2002 Jul;79(7):390-3. University of Nairobi Press; 2002. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
MUTHURE PROFMACHARIAISAAC. "Onyango JF, Macharia IM.Delays in diagnosis, referral and management of head and neck cancer presenting at Kenyatta National Hospital, Nairobi.East Afr Med J. 2006 Apr;83(4):85-91.". In: East Afr Med J. 2006 Apr;83(4):85-91. University of Nairobi Case, in the proceedings of the IST-Africa 2008 Conference; Windhoek, Namibia; 2006. Abstract
BACKGROUND: The most important prognostic factor in head and neck cancer is the stage of the disease at presentation. Early cancer has an excellent prognosis following treatment. Unfortunately most patients present with late disease that requires radical treatment with considerable morbidity and mortality. Clinical experience at Kenyatta National Hospital (KNH) shows that most patients present with late disease. OBJECTIVE: To determine the causes of late presentation of head and neck cancer. DESIGN: A prospective descriptive study. SETTING: Kenyatta National Hospital, Nairobi. RESULTS: Forty four cases were seen among whom 34 were males and 10 were females. The age range was 20 to 90 years with a peak incidence between 50 and 60 years. Most of the patients had little or no education and the majority lived in the rural areas. Seventy one percent of the patients came from the Central and Eastern provinces. Tobacco and alcohol use were the most common risk habits. The larynx was the most common site affected followed by the tongue. In 61% of the cases the size of the tumours at presentation was unknown. In 14% the size was 1-2cm, in 7% of the cases it was 2-4 cm while in 5% of the cases it was 4-6 cm. In 14% of the cases the tumour size was over 6 cm. The most common presenting symptom was hoarseness followed by swelling. The majority of the patients attended a public health facility nearest them. For most patients the facility lay within 5 km and could be accessed by walking. However, most of the patients went through multiple referrals to get to KNH. By the time the patients reached KNH, 35 patients (77%) had been treated with unspecified medications, two (4%) had had tooth extraction, and seven (16%) had had biopsies done. The time-lapse between the first symptom and consultation ranged from zero and eight months. Forty five percent of the patients presented to a medical facility within one month of their symptom and 45% presented after three months. The time lapse between referral and attendance at KNH ranged from zero and thirteen weeks and 45% of the patients presented to KNH within two weeks of referral. The overall duration of symptoms by the time of diagnosis ranged from zero months to unspecified years. Thirty two percent of the cases had experienced symptoms for six months or less by the time of diagnosis. However, a number of patients had had their symptoms for a number of years by the time of diagnosis. The distribution of the tumours by stage at the time of final diagnosis were as follows: stage I were 2%, stage II 6%, stage III 14% and stage IV 56%. CONCLUSION: This study showed that the referral system was the main cause of delayed presentation of head and neck cancer to Kenyatta National Hospital.
FREDRICK DRONYANGOJOHN. "Onyango JF, Macharia IM.Delays in diagnosis, Referral and management of Head and neck cancers presenting at Kenyatta National Hospital.East Afr Med J. 2006 Apr;83(4):85-91.". In: East Afr Med J. 2006 Apr;83(4):85-91. University of Nairobi Press; 2006. Abstract
BACKGROUND: The most important prognostic factor in head and neck cancer is the stage of the disease at presentation. Early cancer has an excellent prognosis following treatment. Unfortunately most patients present with late disease that requires radical treatment with considerable morbidity and mortality. Clinical experience at Kenyatta National Hospital (KNH) shows that most patients present with late disease. OBJECTIVE: To determine the causes of late presentation of head and neck cancer. DESIGN: A prospective descriptive study. SETTING: Kenyatta National Hospital, Nairobi. RESULTS: Forty four cases were seen among whom 34 were males and 10 were females. The age range was 20 to 90 years with a peak incidence between 50 and 60 years. Most of the patients had little or no education and the majority lived in the rural areas. Seventy one percent of the patients came from the Central and Eastern provinces. Tobacco and alcohol use were the most common risk habits. The larynx was the most common site affected followed by the tongue. In 61% of the cases the size of the tumours at presentation was unknown. In 14% the size was 1-2cm, in 7% of the cases it was 2-4 cm while in 5% of the cases it was 4-6 cm. In 14% of the cases the tumour size was over 6 cm. The most common presenting symptom was hoarseness followed by swelling. The majority of the patients attended a public health facility nearest them. For most patients the facility lay within 5 km and could be accessed by walking. However, most of the patients went through multiple referrals to get to KNH. By the time the patients reached KNH, 35 patients (77%) had been treated with unspecified medications, two (4%) had had tooth extraction, and seven (16%) had had biopsies done. The time-lapse between the first symptom and consultation ranged from zero and eight months. Forty five percent of the patients presented to a medical facility within one month of their symptom and 45% presented after three months. The time lapse between referral and attendance at KNH ranged from zero and thirteen weeks and 45% of the patients presented to KNH within two weeks of referral. The overall duration of symptoms by the time of diagnosis ranged from zero months to unspecified years. Thirty two percent of the cases had experienced symptoms for six months or less by the time of diagnosis. However, a number of patients had had their symptoms for a number of years by the time of diagnosis. The distribution of the tumours by stage at the time of final diagnosis were as follows: stage I were 2%, stage II 6%, stage III 14% and stage IV 56%. CONCLUSION: This study showed that the referral system was the main cause of delayed presentation of head and neck cancer to Kenyatta National Hospital.
FREDRICK DRONYANGOJOHN. "Onyango JF, Noah S.Pattern of clefts of the lip and palate managed over a three year period at a Nairobi hospital in Kenya.East Afr Med J. 2005 Dec;82(12):649-51.". In: East Afr Med J. 2005 Dec;82(12):649-51. University of Nairobi Press; 2005. Abstract

BACKGROUND: The pattern of cleft lip and palate in the African population remains uncertain. The few studies of clefts in African populations have suggested that the pattern of these defects may be significantly different from those reported in other population groups. However, most of these studies have been based on very small sample sizes bringing into question the validity of those findings. OBJECTIVE: To analyse the pattern of cleft lip and palate cases managed at a Nairobi hospital. DESIGN: A retrospective descriptive study. SETTING: Gertrude's Garden Children's Hospital, a private exclusive children's hospital in Nairobi, where cleft lip and palate treatment was being offered at subsidised rates to needy children under the sponsorship of an international organization. SUBJECTS: Three hundred and nine cases were seen during the study period. RESULTS: Age at presentation ranged between 1 week and 45 years, with 75% presenting between 0-5 years. The average age was 10 months. Gestation histories were missing for most cases but for those with gestation histories none were significant. Most children ranked between first to third birth orders, suggesting birth to young mothers. Six cases of associated deformities were identified among the cases. No syndromic clefts were seen. The most common cleft deformity was the cleft lip and palate (CL+P) followed by isolated cleft lip (CL). Isolated cleft palate was least common. There was a male preponderance in all cleft types and most of the clefts occurred on the left side. CONCLUSION: The pattern of clefts in this study does not differ significantly from those reported in the literature for the non-African populations.

FREDRICK DRONYANGOJOHN. "Onyango JF, Omondi BI, Njiru A, Awange OOOral Cancer at Kenyatta National Hospital, Nairobi. East Afr Med J. 2004 Jun;81(6):318-21.". In: East Afr Med J. 2004 Jun;81(6):318-21. University of Nairobi Press; 2004. Abstract
BACKGROUND: The epidemiology of oral cancer in the African population is still uncertain. Earlier reports suggested a relatively low incidence of oral cancer among Africans. However, there have been recent reports of an upward trend in the incidence of oral cancers in developing countries as a consequence of changes in life style and the emergence of new diseases. It is, therefore, reasonable to expect changes in the pattern of oral cancer in Kenya in view of these changes. OBJECTIVE: To determine changes in the pattern of oral cancer in the past 20 years. DESIGN: Retrospective descriptive study. SETTING: Kenyatta National Hospital, Nairobi. METHOD: Pathology records of cases of oral cancer diagnosed at Kenyatta National Hospital from 1978 to 1997 were analysed for relative frequency, age, sex and site distribution. RESULTS: Of a total 22,788 malignancies 821 cases (3.6%) were oral cancer. Yearly relative frequency of oral cancer ranged between 1.5% of the total malignancies. There was a small male predominance (M:F = 1.3:1). The most preferred site for oral cancer was the tongue but with a significant number involving the maxilla and mandible. Comparison with a previous study did not demonstrate a dramatic change in the pattern of oral cancer in Kenya. An overall gradual decline of cancers diagnosed at Kenyatta National Hospital was noted. This decline could not be accounted for in this study. CONCLUSION: This study does not show any increase in the frequency or change in the pattern of oral cancer in this population despite changes in life style and the emergence of AIDS disease in the country.
ONYANGO DROGEMBO. "Onyango Ogembo William - Assessment of Water Resources of Kenya with some aspects of their rational utilization, UNESCO/A.A.H.R., Seminar on Hydraulic Research and River Basin Development in Africa, Nairobi.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1980. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Assessment of Water Resources of Kenya with some aspects of their rational utilization, UNESCO/I.A.H.R., Seminar on Hydraulic Research and River Basin Development in Africa, Nairobi, 1980.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1980. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Kenya's River Run-off resources, Izvestiya Journal, Geographical series No.5 pages 88-96. The U.S.S.R. Academy of Sciences, Moscow.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1979. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Kenya's Water Problems, Water Resources Journal. Number 2 pages 171 - 176, The U.S.S.R. Academy of Sciences Moscow.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1977. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Kenya's Water Problems, Water Resources Journal. Number 2 pages 171-176, The U.S.S.R Academy of Sciences Moscow.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1977. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Problems of Water Development in Kenya, Inside Kenya Today Number - 37 page 10-14 Nairobi Kenya.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1977. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Problems of Water Development in Kenya, Inside Kenya Today Number 37 page 10 - 14 Nairobi, Kenya.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1977. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Water balance and the utilisation of water resources in Kenya.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1980. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
ONYANGO DROGEMBO. "Onyango Ogembo William - Water balance and the utilisation of water resources, Izvestiya Journal, Geographical series No. 5 pages 88 - 96, The U.S.S.R. Academy of Sciences, Moscow.". In: Izvestiya Journal, Geographical series NO. 1 pages 90 - 105, U.S.S.R., Academy of Sciences Moscow, 1980. Science; 1979. Abstract
Ogutu EO. A 10-year (1976-1986) retrospective study was done on 30 cases with histological diagnosis of pancreatic carcinoma. The male to female ratio was 1.3:1 and the peak incidence was in the 6th and 7th decades. The head of the pancreas was involved in 96% of cases while solid adenocarcinoma of duct cell origin accounted for 73.3% of cases, followed by anaplastic carcinoma (23.3%). The commonest complications were distinct metastasis (86.6%), obstructive jaundice (73.3%) and upper gastrointestinal bleed (13.6%).
K PROFIMUNGIJASPER. "Onyango, C. M., Shibairo, S. I., Imungi, J. K. and Harbinson, J. 2008. The physico-chemical characteristics and some nutritional value values of vegetable amaranth sold in Nairobi. Ecology of Food and Nutrition 47: 382 .". In: Ecology of Food and Nutrition 47: 382 . Canadian Center of Science and Education; 2008. Abstract
Twenty variceal banding sessions were performed in eight patients between February 1995 and September 1996. A total of 69 rings were used to band the varices and at each session between two to six rings were used. Two of the eight had active bleeding and both underwent variceal banding to successfully arrest their bleeding as inpatients. Sixteen other variceal banding sessions were performed on an outpatient basis to obliterate their varices. Four of the eight patients had had sclerotherapy before and varices were still present. No acute or long term complications were noted. In one patient, variceal banding could not be performed as he developed stridor upon placement of the overtube. All the patients had advanced varices (Grade III or IV) and extended for more than 15 cms in the oesophagus. Endoscopic variceal obliteration remains the treatment of choice for patients with portal hypertension with variceal bleeding. Variceal banding is associated with a superior outcome when compared with sclerotherapy; the variceal kill time is shorter, infective complications less, rebleeding occurs less commonly and transfusion requirements are lower.
WANDAYI PROFOKOTHMICHAEL. "ONYANGO, C.; M.W. OKOTH & S.K. MBUGUA (2000). Effect of drying lactic fermented uji (an East African sour porridge) on some carboxylic acids. .". In: Journal of the Science of Food and Agriculture. University of Nairobi.; 2000. Abstract

Operations Research techniques involving modelling a situation or a problem and finding an optimal solution for it. These tools are not designed nor intended to replace managerial decision making, but rather their purpose is to aid in the decision-making process by providing a quantitative basis for decision making. Unfortunately, the proliferation of OR tools in organizational decision making has been lacking, with concerns been expressed about the limited awareness of the business community of OR's potential and capability. Current study was based in the premise that students provide an appropriate avenue, as agent of change, in sensitizing and demonstrating the potential and capacity of OR tools/techniques in resolving various problems, both in public and private sector. Study aimed at evaluating the use of OR as tools of data analysis at MBA level. A sample of 100 MBA research projects undertaken between 2005 and 2007 was randomly selected and their objectives and selected data analysis tools recorded. Where OR tools were not used, the research evaluated if there was a possibility of using OR tools. Results indicated low usage of OR as data analysis, though there was a high potential for the use of OR tools.

WANDAYI PROFOKOTHMICHAEL. "ONYANGO, C.; M.W. OKOTH & S.K. MBUGUA (2003). The pasting behavior of lactic fermented and dried uji (an East African sour porridge). .". In: Journal of the Science of Food and Agriculture. University of Nairobi.; 2003. Abstract

Operations Research techniques involving modelling a situation or a problem and finding an optimal solution for it. These tools are not designed nor intended to replace managerial decision making, but rather their purpose is to aid in the decision-making process by providing a quantitative basis for decision making. Unfortunately, the proliferation of OR tools in organizational decision making has been lacking, with concerns been expressed about the limited awareness of the business community of OR's potential and capability. Current study was based in the premise that students provide an appropriate avenue, as agent of change, in sensitizing and demonstrating the potential and capacity of OR tools/techniques in resolving various problems, both in public and private sector. Study aimed at evaluating the use of OR as tools of data analysis at MBA level. A sample of 100 MBA research projects undertaken between 2005 and 2007 was randomly selected and their objectives and selected data analysis tools recorded. Where OR tools were not used, the research evaluated if there was a possibility of using OR tools. Results indicated low usage of OR as data analysis, though there was a high potential for the use of OR tools.

K PROFIMUNGIJASPER. "Onyango, C.A., Keya, E.L. and Imungi, J.K. 1993. Aspects of cassava-cereal composite flour quality and appropriate use in some Kenyan food products. Discovery and Innovation 15:241.". In: Proc. 5th Symp. ISTRCAB. pp 332-335. Canadian Center of Science and Education; 1993. Abstract
Twenty variceal banding sessions were performed in eight patients between February 1995 and September 1996. A total of 69 rings were used to band the varices and at each session between two to six rings were used. Two of the eight had active bleeding and both underwent variceal banding to successfully arrest their bleeding as inpatients. Sixteen other variceal banding sessions were performed on an outpatient basis to obliterate their varices. Four of the eight patients had had sclerotherapy before and varices were still present. No acute or long term complications were noted. In one patient, variceal banding could not be performed as he developed stridor upon placement of the overtube. All the patients had advanced varices (Grade III or IV) and extended for more than 15 cms in the oesophagus. Endoscopic variceal obliteration remains the treatment of choice for patients with portal hypertension with variceal bleeding. Variceal banding is associated with a superior outcome when compared with sclerotherapy; the variceal kill time is shorter, infective complications less, rebleeding occurs less commonly and transfusion requirements are lower.
MUNGE PROFMUKUNYAD. "Onyango, D. and D.M. Mukunya. 1982. Bacterial blight of cassava, Xanthomonas manihotis in Kenya.". In: Proceedings of the Workshop on root and Tuber crops held in Burundi. IITA. Ibadan, Nigeria. Plant Molecular Biology Reporter Vol. 27, pp. 79-85.; 1982. Abstract
The gene Q13L coding for the Capripoxvirus group specific structural protein P32 was expressed in Escherichia coli using plasmid pGEX-2T as a fusion protein with glutathione-s-transferase and purified on glutathione sepharose affinity chromatography column. The protein was then employed for diagnosis of sheeppox, goatpox and lumpyskin disease, by a latex agglutination test (LAT) using the purified P32 antigen and guinea pig detector antiserum raised against the P32 antigen. The LAT and virus neutralization test (VNT) were used to screen one hundred livestock field sera for antibodies to Capripoxvirus, in comparison the LAT was simpler, rapid and 23% more sensitive than the VNT. In addition the LAT was found to be specific for Carpripoxvirus because it did not pick antibodies to Orthopoxvirus and Parapoxvirus. The LA test can be taken for a simple and quick diagnostic tool for primary screening of Carpripoxvirus infection and will reduce the reliance of diagnostic laboratories on tissue culture facilities. Keywords: Carpripox, latex agglutination test, attachment gene J. Trop. Microbiol. Biotechnol. Vol. 3 (2) 2007: pp. 36-43
. DRONYANGODANIELW. "Onyango, D. W (1992): Histological and ultrastructural study of the male reproductive system of non-breeding naked mole rats (Heterocephalus glaber, Ruppell) and in vitro interstitial (Leydig) cell response to luteinizing hormone (LH). MSc. thesis,univers.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1992. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W (2001): Effects of ethane dimethanesulphonate (EDS) on testicular and epididymal structure, and plasma testosterone profiles in the goat (Capra hircus). Ph.D thesis, University of Nairobi, Kenya.". In: MSc. Thesis, University of Nairobi. Kisipan, M.L.; 2001. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Gachoka, J. M., Otiang.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1995. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Oduor-Okelo, D & Otiang.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1993. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Oduor-Okelo, D & Otiang.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1992. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

ODUOR PROFOKELLODOMINIC. "ONYANGO, D. W., ODUOR-OKELO, D. & OWITI, G E.O.(1993).Ultrastructural study of the testis of non-breeding naked mole rat (Heterocephalus glaber, Ruppell).Annals of Anatomy 175: 447-452.". In: J. Comp. Biochem. Physiol. 111 C (2): 191-196. Kisipan, M.L.; 1993. Abstract
Adult female Sprague-Dawley rats were injected with corn oil or 5 mg, 20 mg, 25 mg or 30 mg per kg body weight of heptachlor solution every other day for up to 18 days. The rats were killed at the end of the experimental period, and blood samples were assayed for progesterone and oestrogen by radioimmunoassay. Ovarian cells from the rats were isolated and incubated either on their own, or in the presence of LH or FSH, and production of progesterone and oestrogen determined. Control incubations consisted of cells from corn oil-treated rats. The latter were also incubated on their own or in the presence of LH or FSH. Heptachlor significantly suppressed blood progesterone and oestradiol levels (P < 0.05 to P < 0.001), the degree of suppression depending on the dose and the stage of the oestrous cycle in which samples were obtained. Production of oestradiol by ovarian cells from heptachlor-treated rats was lower than for corn oil-treated controls. Cells from rats treated with low doses of heptachlor (5 mg per kg body weight) showed an increased production of progesterone, while high doses (> 20 mg per kg body weight) suppressed production.
. DRONYANGODANIELW. "Onyango, D. W., Otiang.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1991. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

ODUOR PROFOKELLODOMINIC. "ONYANGO, D. W., OWITI, G.E.O., ODUOR-OKELO, D. & MAKAWITI, D. W.(1991). In vitro testicular interstitial (Leydig) cell response to LH and concentration of plasma testosterone and LH in the naked mole rat (Heterocephalus glaber, Ruppel). Afr. J. Ecol. Vol.". In: J. Comp. Biochem. Physiol. 111 C (2): 191-196. Kisipan, M.L.; 1991. Abstract
Adult female Sprague-Dawley rats were injected with corn oil or 5 mg, 20 mg, 25 mg or 30 mg per kg body weight of heptachlor solution every other day for up to 18 days. The rats were killed at the end of the experimental period, and blood samples were assayed for progesterone and oestrogen by radioimmunoassay. Ovarian cells from the rats were isolated and incubated either on their own, or in the presence of LH or FSH, and production of progesterone and oestrogen determined. Control incubations consisted of cells from corn oil-treated rats. The latter were also incubated on their own or in the presence of LH or FSH. Heptachlor significantly suppressed blood progesterone and oestradiol levels (P < 0.05 to P < 0.001), the degree of suppression depending on the dose and the stage of the oestrous cycle in which samples were obtained. Production of oestradiol by ovarian cells from heptachlor-treated rats was lower than for corn oil-treated controls. Cells from rats treated with low doses of heptachlor (5 mg per kg body weight) showed an increased production of progesterone, while high doses (> 20 mg per kg body weight) suppressed production.
. DRONYANGODANIELW. "Onyango, D. W., Wango, E. O and Werner, G (2001): Epididymal epithelial cell involution following a single intraperitoneal administration of ethane dimethanesulphonate (EDS) in the goat (Capra hircus). Toxicol. Appl. Pharmacol. 175(1): 19-27.". In: MSc. Thesis, University of Nairobi. Kisipan, M.L.; 2001. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Wango, E. O. Odongo, H., Mugweru, J & Okindo, E (1998):Effects of heptachlor on rat plasma LH, testosterone and cortisol and testicular structure. In;.". In: Proceedings of the First Meeting of Federation of African Societies of Biochemistry and Molecular Biology(FASBMB) (Eds. Ochanda, J. O., Kiaira, J. K & Makawiti, D. W.),pp.195-198. Biochemical Society of Kenya. Kisipan, M.L.; 1998. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Wango, E. O., Oduor-Okelo, D and Werner, G (2001): Early testicular response to intraperitoneal administration of ethane dimethanesulphonate (EDS) in the goat (Capra hircus). J. Submicrosc.Cytol. Pathol., 33(1-2): 117-124.". In: MSc. Thesis, University of Nairobi. Kisipan, M.L.; 2001. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

. DRONYANGODANIELW. "Onyango, D. W., Wango, E. O., Otiang.". In: MSc. Thesis, University of Nairobi. Kisipan, M.L.; 2000. Abstract

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml. 6 mg/ml. 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3 h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml. 0.6 mg/ml and 6 mg/ml) significantly stimulated (P < 0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r= 0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations. may enhance testosterone production with accompanying effects on reproductive functions in male mice. @2006 Publishedby Elsevier Ireland Ltd. Kel'lVords: In dtro; Khat; Testosterone; Interstitial cells; Mouse

MBAABU DRMATHIUPETER. "Onyango, E.M. and Mathiu P.M. (1999). The normal hemogram and Oxygen affinity of hemoglobin in the Maasai ostrich.". In: The joint Commonwealth Veterinary Association (CVA)/Kenya Veterinary Association (KVA) regional conference for Eastern, Central and Southern Africa, Nairobi. Elsevier; 1999. Abstract
Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya
IKUSYA PROFKANUITITUS. "Onyango, E.M., Buoro I.B.J., Kanui T.I. and Maina, J.N. Correlation between electrocardiographic characteristics with morphometric features in experimental early, mild heartworm disease Bulletin of Animal Production Africa, 42 (1994) : 41 - 45.". In: Symposium held on the Launch of Tramal, Eldoret 1994 P1 Abs. Elsevier; 1994. Abstract
Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya
IKUSYA PROFKANUITITUS. "Onyango, E.M., Buoro, I.B.J. and Kanui, T.I. Arrhythmias associated with experimental pulmonary embolism in the dog. The Kenya Veterinarian 16 (1992) 21 .". In: Proceedings of The First International Congress of The African Association of Physiological Sciences, Nairobi, Kenya, September, 21-28, 1992, 17 (Abs.), pp.8. Elsevier; 1992. Abstract
Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya
IKUSYA PROFKANUITITUS. "Onyango, E.M., Buoro, I.B.J., Kanui, T.I. Induction of pulmonary hypertension in the dog using poly vinyl chloride threads. Israel Journal of Veterinary Medicine, 49 (1) (1994) 31 .". In: Symposium held on the Launch of Tramal, Eldoret 1994 P1 Abs. Elsevier; 1994. Abstract
Ethnopharmacological relevance: Traditional medicines play an important role in the management of chronically painful and debilitating joint conditions, particularly in the rural Africa. However, their potential use as sources of medicines has not been fully exploited. The present study was carried to find the medicinal plants traditionally used to manage chronic joint pains in Machakos and Makueni counties in Kenya. Materials and methods: To obtain this ethnobotanical information, 30 consenting traditional herbal med-ical practitioners were interviewed exclusively on medicinal plant use in the management of chronic joint pains, in a pre-planned workshop. Results and discussion: In this survey, a total of 37 plants belonging to 32 genera and 23 families were cited as being important for treatment of chronic joint pains. The most commonly cited plant species were Pavetta crassipes K. Schum, Strychnos henningsii Gilg., Carissa spinarum L., Fagaropsis hildebrandtii (Engl.) Milve-Redh. and Zanthoxylum chalybeum Engl. Acacia mellifera (Vahl) Benth., Amaranthus albus L., Balanites glabra Mildbr. & Schltr., Grewia fallax K. Schum., Lactuca capensis, Launaea cornuta (Oliv. & Hiern) O. Jeffrey, Lippia kituiensis Vatke, Pappea capensis Eckl. & Zeyh. and Pennisetum glaucum (L.) R. Br. are documented for the first time as being important in the management of chronic joint pains. Conclusions: The findings of this study show that a variety of medicinal plants are used in the management of chronic joint pains and the main mode of administration is oral. Keywords: Ethnobotanical survey; Medicinal plants; Chronic joint pains; Rheumatoid arthritis; Akamba; Machakos-Kenya
FREDRICK DRONYANGOJOHN. "Onyango, J.F,. Kayima, J.K, and Owen, W.O: East Afr Med J. 2002 Jul;79(7):390-3.". In: East Afr Med J. 2002 Jul;79(7):390-3. University of Nairobi Press; 2002. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
FREDRICK DRONYANGOJOHN. "Onyango, J.F. and Awange, D.O.: Primary malignant fibrous histiocytoma of the mandible: A case report.East Afr Med J. 1993 Jul;70(7):460-3.". In: East Afr Med J. 1993 Jul;70(7):460-3. University of Nairobi Press; 1993. Abstract
A case report of a primary malignant fibrous histiocytoma (MFH) in the mandible of a young adult male is presented and relevant literature reviewed. The clinical presentation and course of the case is typical of MFH of the jaw as reported in the literature
FREDRICK DRONYANGOJOHN. "Onyango, J.F. and Mwangi W. N.: Medical Audit in the Department of Oral and Maxillofacial Surgery, Division of Dental Surgery, Kenyatta National Hospital, Nairobi. The New Afric. Journal of medicine. 1997; 2; 26 .". In: The New Afric. Journal of medicine. 1997; 2; 26 . University of Nairobi Press; 1997. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
FREDRICK DRONYANGOJOHN. "Onyango, J.F., Awange, D.O. and Wakiaga, J.M.: Ameloblastoma: A clinico pathological analysis of 176 cases, Afric. J. Oral Health Sci, 2001; 2:4 .". In: Afric. J. Oral Health Sci, 2001; 2:4 . University of Nairobi Press; 2001. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
FREDRICK DRONYANGOJOHN, FREDRICK DRONYANGOJOHN. "Onyango, J.F., Awange, D.O. and Wakiaga, J.M: Oral tumours and tumour-like conditions in Kenya: I. Histological distribution. East Afr Med J. 1995 Sep;72(9):560-3.". In: East Afr Med J. 1995 Sep;72(9):560-3. University of Nairobi Press; 1995. Abstract

A histological analysis of 3141 cases of oral tumours and tumour-like lesions diagnosed at Kenyatta National Hospital between 1978 and 1992 has been carried out. Squamous cell carcinoma, salivary gland tumours and lymphoid tumours form the majority of lesions. In general, the histological distribution of the oral tumours do not differ significantly from those reported in non African series save for the Burkitt's lymphoma.

FREDRICK DRONYANGOJOHN. "Onyango, J.F., Awange, D.O., Muthamia, J.M., Muga, B.I.O.: Salivary Gland Tumours in Kenya.East Afr Med J. 1992 Sep;69(9):525-30.". In: East Afr Med J. 1992 Sep;69(9):525-30. University of Nairobi Press; 1992. Abstract
Four hundred and seventeen tumours of salivary glands in Kenya were analysed. There is no evidence of higher incidence of salivary tumours than in non-African countries. The pattern of distribution differed from that of western countries, but in conformity with most African series showed a low proportion of tumours of the parotid gland and high proportion of tumours in the submandibular gland and the palate. The involvement of the palate by salivary gland tumour is very prominent in the African series and particularly more so in the females. Malignant tumours of the palate and parotid glands were frequent but were lower than those reported in other African series. On the other hand malignant salivary gland tumours of the submandibular glands while lower than those of the western countries, were higher than those of other African series.
FREDRICK DRONYANGOJOHN. "Onyango, J.F., Awange, D.O.: Ameloblastic Sarcoma of the Mandible: A case report, Afric J of Oral Health Sciences, 2000; 1:.". In: Afric J of Oral Health Sciences, 2000; 1:. University of Nairobi Press; 2001. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
FREDRICK DRONYANGOJOHN. "Onyango, J.F., Njiru, A. Kaposis sarcoma in a Nairobi hospital. East Afr Med J. 2004 Mar;81(3):120-3.". In: East Afr Med J. 2004 Mar;81(3):120-3. University of Nairobi Press; 2004. Abstract

BACKGROUND: Kaposi's sarcoma (KS) is associated epidemiologically with HIV infection and a number of countries have reported a dramatic increase in the incidence of KS with the advent of AIDS. Although AIDS is prevalent in Kenya, no studies on the impact of AIDS on the pattern of KS has been carried out. OBJECTIVE: To determine any changes in the pattern of KS that might have occurred since the advent of AIDS in the country. DESIGN: Retrospective descriptive study. SETTING: Kenyatta National Hospital (KNH). METHOD: Pathology records of cases of KS diagnosed at KNH from 1968 to 1997 were analysed with respect to relative frequency, age, sex and site distribution; and trend. The period was divided into the pre and post AIDS era from 1983, which is the time the first AIDS patient was reported in the country. RESULT: A total of 1108 cases of KS consisting of 911 males and 197 females were recorded. The relative frequency of KS ranged between 2% to 5% of the total malignancies. There was a gradual decline in the male to female ratio from about 10:1 in the sixties to about 2:1 in 1997. There was no dramatic difference in the age distribution in the pre and post AIDS era, although a large number of cases were recorded as adults without age specification in the post AIDS era. Site distribution was characteristic of the disease with most of the cases having the lesions occurring in the lower limbs and involving the skin. CONCLUSION: Although these findings do not demonstrate a dramatic alteration in the pattern of KS in the post AIDS era there were indications that such changes may have been obscured by under-reporting. The fall in the male:female ratio is a strong indication of a rise in KS among female patients. A further study is necessary to elucidate the true impact of AIDS on the pattern of KS in the country.

FREDRICK DRONYANGOJOHN. "Onyango, J.F.: Cleft Lip/Cleft Palate and Oral Facial Defect Management: The need for Oro-facial cleft center in Kenya. Medicom. 1982; 4:.". In: Medicom. 1982; 4:. University of Nairobi Press; 1982. Abstract
This communication presents the first case report of ossifying fibroma of the jaw from Kenya and reviews the literature including the available published case reports from Africa. The relationship between ossifying fibroma and other related benign fibro-osseous lesion of the jaws is briefly discussed. Intensified research work on this condition in Africans is called for so that more cases should be published since it is reportedly more common in black race. The majority of the African cases are generally reported in advanced stages indicating neglect or delay in seeking for medical help. Since ossifying fibroma is a well encapsulated and expansile benign bone neoplasm, surgical enucleation appears to be the treatment of choice; recurrence is rare.
FREDRICK DRONYANGOJOHN. "Onyango, J.F.: Prabu S.R. Oral Cancer in Kenya. Medicom, 1980; 2: 87 -90.". In: Medicom, 1980; 2: 87 -90. University of Nairobi Press; 1980. Abstract
This communication presents the first case report of ossifying fibroma of the jaw from Kenya and reviews the literature including the available published case reports from Africa. The relationship between ossifying fibroma and other related benign fibro-osseous lesion of the jaws is briefly discussed. Intensified research work on this condition in Africans is called for so that more cases should be published since it is reportedly more common in black race. The majority of the African cases are generally reported in advanced stages indicating neglect or delay in seeking for medical help. Since ossifying fibroma is a well encapsulated and expansile benign bone neoplasm, surgical enucleation appears to be the treatment of choice; recurrence is rare.
FREDRICK DRONYANGOJOHN. "Onyango, J.F: Ameloblastoma: Where are we? Afric. J. Oral Health Sci. 2001; 2: 2.". In: Afric. J. Oral Health Sci. 2001; 2: 2. University of Nairobi Press; 2001. Abstract
Rhinocerebral mucormycosis is a rare, fulminating opportunistic fungal infection caused by a fungus of the order mucorales. These fungi are ubiquitous, subsisting on decaying vegetation and diverse organic material. Although the fungi and spores of mucorales show minimal intrinsic pathogenicity towards normal persons, they can initiate aggressive and fulminating infection in the immune compromised host. Because rhinocerebral mucormycosis occurs infrequently it may pose a diagnostic and therapeutic dilemma for those who are not familiar with its clinical presentation. We present a patient with classical presentation of rhinocerebral mucormycosis involving the paranasal sinuses, the orbit and cranial base who, was treated by a combination of aggressive surgical and medical therapy and subsequently had surgical repair of the oral defect. The purpose of this presentation is to draw attention to the clinical presentation and pathogenesis of rhinocerebral mucormycosis and to emphasise the need for high index of suspicion in its diagnosis and management.
K PROFIMUNGIJASPER. "Onyango, M. C. and Imungi, J. K. 2007. Post harvest handling and characteristics of fresh-cut traditional vegetables sold in Nairobi-Kenya. Proc. African Crop Science Conference, 27 .". In: African Crop Science Conference, 27 . Canadian Center of Science and Education; 2007. Abstract
Twenty variceal banding sessions were performed in eight patients between February 1995 and September 1996. A total of 69 rings were used to band the varices and at each session between two to six rings were used. Two of the eight had active bleeding and both underwent variceal banding to successfully arrest their bleeding as inpatients. Sixteen other variceal banding sessions were performed on an outpatient basis to obliterate their varices. Four of the eight patients had had sclerotherapy before and varices were still present. No acute or long term complications were noted. In one patient, variceal banding could not be performed as he developed stridor upon placement of the overtube. All the patients had advanced varices (Grade III or IV) and extended for more than 15 cms in the oesophagus. Endoscopic variceal obliteration remains the treatment of choice for patients with portal hypertension with variceal bleeding. Variceal banding is associated with a superior outcome when compared with sclerotherapy; the variceal kill time is shorter, infective complications less, rebleeding occurs less commonly and transfusion requirements are lower.
MORAA DRONYANGOCECILIA. "Onyango, M.C. and Silim, S.N. Effect of genotype, storage temperature, Shelling and duration of storage on quality of vegetable pigeonpea. In: Silim, S.N., Mergeai, G., and Kimani, P.M. (eds) 2001.". In: Status and Potential of pigeonpea in Eastern and Southern Africa: Proceedings of a regional workshop, 12-15 Sep. 2000, Nairobi, Kenya. African Crop Science Society; 2001. Abstract
Twenty one major supermarkets and ten independent green grocers in the city of Nairobi were surveyed for the types of fresh-cut traditional leafy vegetables (TLVs) sold. Cleome gynandra, Solanum nigrum, Vigna unguiculata, Amarathus spp. and Cucurbita spp were found to be the most common TLVs selling. Amaranthus spp. and Solanum nigrum were selling in all the sales outlets surveyed, while the rest were selling in only a few of the sales outlets. For vending, the vegetables were not afforded any formal packaging; instead the vegetables within each type were tied in bundles of similar average size and displayed in troughs or shelves. The average weight of the bundles ranged between 250g for Cucurbita spp. to 650g for Vigna unguiculata. The mean price per bundle was KSh 14.00. The edible portion per bundle averaged between 34.2% for Vigna unguiculata and 84% for Cucurbita spp. Most of the sales outlets sold proportions ranging between 94% and 97% of the total delivery of the vegetables. The major cause of deterioration of the vegetables during vending was wilting. However, it was indicated that significant losses also occurred through spillage. The study concludes that TLVs are becoming important as commercial crops and as items of diets for Kenyans of all levels. Studies on simple postharvest handling to minimize the losses are however, required.
MUCHAI PROFKAGIKOM, MWANGI PROFGATHUMAJ. "Onyango-Abuje, J.A., Waiyaki, P.G. and Gathuma, J.M. (1989). Specific and shared antigen components of Taenia saginata oncospheres. Research in Veterinary Science 4, 236 .". In: journal. FARA; 1989. Abstract
Bacillus cereus strains were tested for production of diarrheal enterotoxin by the reverse passive latex agglutination test and for presence of B. cereus enterotoxin gene (bceT) by polymerase chain reaction. About 50% of 56 B. cereus strains reacted positive in broth culture in the reverse passive latex agglutination test, while the bceT gene was detected in 41.1 % of the strains. A 741 bp probe prepared from the polymerase chain reaction product detected bceT gene in all strains that were positive with the polymerase chain reaction. This study indicated a likelihood of two or more enterotoxins being produced by B. cereus which may be involved in causing diarrheal type food poisoning.
MUCHAI PROFKAGIKOM, MWANGI PROFGATHUMAJ. "Onyango-Abuje, J.A., Waiyaki, P.G. and Gathuma, J.M. (1989). Specific and shared antigen components of Taenia saginata oncospheres. Research in Veterinary Science 4, 236 .". In: Nairobi Journal of Medince 1: 23, 1970. au-ibar; 1989. Abstract
No abstract available.
ONYANGO-OUMA DRW. "Onyango-Ouma, W. 2003. Children as partners in health communication in a Kenyan community. Anthropology in Action 10 (1): 25-33.". In: Nordic Journal of African Studies 15 (3): 393-40. Population Council; 2003. Abstract
Anthropology at home: Perspectives and ethical dilemmas. Mila (N.S.) 5: 90-97.
Kipkoech, D. N.;, Ng’anga NW;, Kabira JN;, Abong GO;, Nderitu JH. "On‐farm seed potato storage practices in Kenya: A case study of Nyandarua."; 2012.
Kipkoech, D. N.;, Ng’anga NW;, Kabira JN;, Abong GO;, Nderitu JH. "On‐farm seed potato storage practices in Kenya: A case study of Nyandarua."; 2012.
N.I DROONGEZABLON. "Oonge Z and Parkin G.F. Poisoning of Sulfate Reductions with Molybdenum in Anaerobic Reactors Fed Glucose.". In: In Proceedings of the 45th Industrial Waste Conference May 8, 9, 10, 1990; Purdue University. World Conference of Phylosophy Proceedings; 1990.
Donnelly TM, Srivastava KK, Oyejide A, Kanyari PW, Ngatia TA, Mbaabu-Mathiu P. "Oozing ostrich egg: omphalitis caused by Enterobacter sp.". 2002.
Martin PG, Heydenreich M, M. S, Midiwo.' JO, Yenesew A. "Op-37 Flavonoids from erythrina burttii and erythrina sacleuxii.". 2000. AbstractOp-37 Flavonoids from erythrina burttii and erythrina sacleuxii

The root and stem bark of Erythrina species are widely used in traditional medicine for the treatment of microbial infections: In our interest on the phytochemistry of Erythrina species of Kenya, we have isolated several flavonoids, including new flavanones (eg. 1) and isoflav-3-enes (eg 2) from Erythrina burttii; isoflavones (eg. 3) and isoflavanones (eg. '1) from Erythrina sac/euxii. Some of these compounds show antibacterial, anti-fimgal, anti-malarial and anti-oxidant activities. The structure elucidation and biological activities of some of these compounds will be discussed.

Kabugu A, Gikunju M. Open access and the role of the librarian.; 2014.
Zachariah R, Kumar AMV, Reid AJ, den Bergh VR, Isaakidis P, Draguez B, Delaunois P, Nagaraja SB, Ramsay A, Reeder JC, Denisiuk O, Ali E, Khogali M, Hinderaker SG, Kosgei RJ, van Griensven J, Quaglio GL, Maher D, Billo NE, Terry RF, Harries AD. "Open access for operational research publications from low and middle-income countries: who pays?" Public Health Action . 2014;4(3):141-144.open_acess_for_operations_research_who_pays.pdf
Gikunju M. Open Access Initiatives .; 2014.
Gikunju M. Open Access Resources .; 2015.
Masinde M. Open Access4D: Battle not won.; 2015. Abstract

The trend is still: “transferring of Northern designs to Southern realities” While 41% of the world’s household have access to the Internet, Africa is lagging far behind at 9%. Africa has abysmal penetration rate for landline telephone, the number of fixed-broadband subscriptions Internet has increased the digital divide.... Africa is slow to take up technological innovation as most have to be imported from elsewhere..” Liam (2009)

WAMBUGU LYDIAH, NDUNGE KYALODOROTHY. "Open and Distance Education as a Strategy for Improving Higher Education in the 21st Century in Kenya- a case of the University of Nairobi." Journal of Education and Practice. 2013;, Vol.4 (14 2013. ISSN 2222-1735 ).
WAMBUGU LN, KYALO DN. "Open and Distance Education as a Strategy for Improving Higher Education in the 21st Century in Kenya- a case of the University of Nairobi.". In: 3rd ACDE Conference and General Assembly . Dar es Salaam , Tanzania; 2011.
O DROPEREALFRED. "OPEN AND DISTANT LEARNING MATERIALS WRITTEN & REVIEWED: 1. SMR 103: Quantitative methods & Computer Applications I 2. SMR 309: Hydrometeorology I 3. SMR 307: Thermodynamics & Cloud Physics.". In: University of Nairobi. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2010. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
MalariaGEN, Ahouidi A, Ali M, et al. "An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples." Wellcome Open Res.. 2021;6:42. Abstract

MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

Tamimi IFM, Patel NB. "Open field ethogram and olfactory preference in naked mole rat (Heterocephalus glabus). .". In: Society of Neuroscientists of Africa. Entebbe, Uganda; 2017.imaan_-_sona_poster__27_may_2017.pdf
A. PROFODHIAMBOPETER. "Open Heart Surgery - MEDICOM.". In: The African Journal of Hospital Medicine. Heinrich Boll Foundation.; 1980. Abstract
A retrospective study of 42 patients with perforations of the oesophagus during the period 1981-1987 indicated that 57.1% of the perforations were iatrogenic. Diseases of the oesophagus and in contiguous structures and foreign bodies in the oesophagus caused perforations in 31% of the cases. Perforations in 35.7% of the patients were located in the middle third of the oesophagus. The lower and upper thirds were affected in 31% of the patients in each site. The presenting physical signs included tachycardia (78.6%), fever (76.2%) and dyspnoea (59.5%). The main accompanying symptoms were chest pain and coughs in 100% and in 50% of the patients respectively. Radiographic findings showed hydropneumothorax in 40.5% of the cases and consolidation in 38.1% of the patients. Oesophagoscopy was positive in 78% of cases tested while thoracocentesis was positive in all cases that were tested.
Kanyinga K. "An open letter to governors: How to get quick wins in first three months." Sunday Nation, August 27, 2017.
W DRGETAOKATHERINE. "Open Source Software Adoption in Kenyan Tertiary Education: Opportunities, Challenges And Methodology.". In: International ICT Workshop 2004 On Application of ICT in enhancing Higher Learning Education, pp 34-51. East African Orthopaedic Journal; 2004.
Machera M, ed) SA(. Opening a Can of Worms: A Debate on Female Sexuality in the Lecture Theatre. Uppsala: Nordic Africa Institute; 2004.
VERONICA MISSMWENDE. "Opening A Video Library.". In: Bull. Environ. Contam. Toxicol. Bull. Environ. Contam. Toxicol; 2002. Abstract
The paper shows that in the analysis of a queuing system with fixed-size batch arrivals, there emerges a set of polynomials which are a generalization of Chebyshev polynomialsof the second kind. The paper uses these polynomials in assessing the transient behaviour of the overflow (equivalently call blocking) probability in the system. A key figure to noteis the proportion of the overflow (or blocking) probability resident in the transient component,which is shown in the results to be more significant at the beginning of the transient and naturally decays to zero in the limit of large t. The results also show that the significanceof transients is more pronounced in cases of lighter loads, but lasts longer for heavier loads.
E.N. PN. "Opening speech to Coast Branch N.N.A.K. AGM on team work and nurses welfare.". In: Opening speech to Coast Branch N.N.A.K. AGM on team work and nurses welfare.; 1981. Abstract

Kenya Nurs J. 1981 Jun;10(1):21-2.
Opening speech to Coast Branch N.N.A.K. AGM on team work and nurses welfare.
Ngugi EN.

PMID:
6913629
[PubMed - indexed for MEDLINE]

The following toggler user interface control may not be accessible. Tab to the next button to revert the control to an accessible version.
Destroy user interface controlMeSH Terms

Irandu EM. "Opening up African Skies: the case of Airline Industry Liberalization in East Africa." JOURNAL OF THE TRANSPORTATION RESEARCH FORUM, Vol.47, No.1: 73-89.. 2008;Vol.47, No.1: 73-89.
F EA, N MJ, K KC. "Openings Effects on the Performance of Reinforced Concrete Beams Loaded in Bending and Shear." Engineering, Technology & Applied Science Research. 2020;Vol 10(2):5352-5360.
OGEDA MRODUMBEJACKONIAH. "Operation of the Institute of Distance Education of the University of Swaziland published as an Occasional Paper for DEASA by the International Extension College London.". In: Seminar on African University Day of UNISWA 15th November 2002. Thought and Practice; 2002. Abstract
Introduction The Centre for Open and Distance Learning has been established to facilitate the Internal Faculties in launching and managing their programmes using distance mode with a view to increasing access to university education and provide equity in higher education to the learners all over the country. Operational Strategies The operational strategies that have been set up involve collaborative arrangements between the CODL and the Internal Faculties in the development of Study Materials and Learner support Services for off-campus students. The professional in open and distance learning are availed by the Centre to serve the Faculties as trainers while the Faculties provide academic expertise who are facilitated through participatory methods involving application of knowledge, skills and strategies to develop study materials in their respective subjects. Focus The Centre is currently working with Faculties of Science, Commerce and Arts. The Material development process involves training, writing, reviewing and editing followed by conversion to e-content and audio modes. Conclusion These collaborative arrangements will increase access to higher education make significant contribution in the realization of educational Millennium Goals in Kenya where only 20% of all those who qualify obtain admission in the public universities.
MALECHE MRZACHARIAH. "The operation of the Integrated LADP process." In collaboration with the Green Towns project on Environment and Urban Development, ministry of Local Government. 1996.". In: KISE Bulletin, July 1987. Vol. 1 No. 2. World Conference of Phylosophy Proceedings; 1996.
Iminza NW, Kiragu ND, L GW. "OPERATIONAL GOVERNANCE AND OCCUPATIONAL FRAUD RISK IN COMMERCIAL BANKS IN KENYA: A POSITIVISM APPROACH." European Journal of Business Management. 2015;2(1):401-423. Abstract

Association of Certified Fraud Examiners caution that globally, a typical organization loses at
least 5% its annual revenue through occupational fraud. Further statistics indicate that
occupational fraud risk is highest in commercial banks than any other industry globally.
Occupational fraud risk is therefore a global problem. The problem is that Kenya has the highest
incidences of fraud is East Africa. The study set to determine the effect of operational
governance on occupational fraud risk in commercial banks in Kenya. Using a positivism
research paradigm and a descriptive research design, a representative stratified sample of 30
commercial banks out of the 43 commercial banks licensed by Central Bank of Kenya by June
30, 2012 was used in this study. Principal Component Analysis, Varimax, Orthogonal was used
for Factor analysis. Kaiser-Meyer-Olkin test of sampling adequacy was used together with
Bartlett’s test of Sphericity to assess factorability of the predictor variable. Cronbach’s alpha
coefficient was used to assess the data collection tool for stability and consistency. Factor
analysis was used to asses construct validity. In order to test the null hypothesis, that is, there is
no relationship between operational governance and occupational fraud risk in commercial banks
in Kenya, model fitness, ANOVA and Regression coefficients were generated and interpreted.
The study found that there is a positive but weak correlation between operational governance and
occupational fraud risk. Further, the study found that the relationship is not statistically
significant. These results provide insights into the occupational fraud risk controls relevance and

OKETCH UK, Chokwe T, MUNG'AYI V. "The operational setup of intensive care units in a low income country in East Africa: a cross sectional survey. ." East African Medical Journal. 2015;92(2):72-80.
GITHII MW. "OPERATIONS RESEARCH II DISTANCE LEARNING MANUAL.". In: Proceedings of the Third Conference on Information Technology and Economic Development. 2004 Ghana .INTERCED. Ghana: Ahmed C.M., Dabelic R., Waiboci L., Jager L.D., Heron L.L. and Johnson H.M.; 2009. Abstract

n/a

MEROKA PROFMBECHEISAAC, S.O.Nyamwange. "Operations Strategies Applied for the Competetitiveness of Kenyan Large Manufacturing Firms.". In: Nairobi Journal of Management, Vol. 6 May-September, 2003. IBIMA Publishing; 2003. Abstract

This research sought to survey the manufacturing strategies pursued by the large manufacturing firms in Kenya as a way of remaining a float in the turbulent "libero-global' environment. The survey was carried out among the large manufacturing firms in Kenya. A total of seventy large firms picked through stratified sampling from a sample frame of 260, were sent questionnaires and twenty seven completed and returned them. The findings indicate the presence of trade-offs on one hand and order-winners and qualifiers on the other, also, it was found that all firms, regardless of company characteristics, compete on similar operations strategies. In particular, firms ranked, in order of priority, the following strategies: (1) high quality (2) low cost (3) time/speed, innovativeness and flexibility. The findings of this research indicate the majority of large manufacturing firms acknowledge that operations- based strategies enhance the competitive capabilities of their firms by contributing to long-term business performance and success. In order to mobilize their competitiveness, firms need to emphasize high quality and consistence, low cost and hence low price, time/speed, dependability, innovativeness and high flexibility.

 Mbeche IM, Onserio NS. "Operations Strategies applied for the competitiveness of Kenyan large manufacturing firms." Hekima Journal of the Humanities and Social Sciences. 2003;Vol. 2. (No.1).
Ojuka DK, Macleod J, Nyabuto CK. "Operative Exposure of a Surgical Trainee at a Tertiary Hospital in Kenya." Surg Res Pract. 2015;2015:724506. Abstract

Background. Psychomotor domain training requires repetitive exposure in order to develop proficiency in skills. This depends on many training factors in any training institution. Objective. This study sought to look at the operative exposure of surgical trainees in a tertiary hospital in a developing country. Design and Setting. This was a six-month retrospective study performed in one surgical firm at Kenyatta National Hospital. Patients and Methods. The files of all patients admitted to the unit at that time were retrieved. The demographics, diagnosis at admission, need for surgery, and cadre of operating surgeon among others were recorded. Scientific Package for Social Sciences (SPSS) version 17.0 was used for data entry and analysis. Results. The study cohort was 402 patients of the 757 patients admitted in the study period. The average age was 36.7 years, a female to male ratio of 1 : 2.5. The majority (69.7%) of patients required surgery. Trauma was the most common reason for admission (44.5%). Year 2 residents received the most clinical exposure. Consultant was available in only 34.5% of the cases. Conclusion. The junior residents performed the vast majority of procedures with an unsatisfactory amount of supervision from the senior residents and faculty.

Langdon J, Patel M, Brennan P. Operative {Oral} and {Maxillofacial} {Surgery} {Second} edition. 2nd ed. CRC Press; 2010. Abstract

Operative Maxillofacial Surgery was first published in 1998, and within a very short period it became the standard text for trainees in oral and maxillofacial surgery preparing for their exit examinations.For this second edition, the contents have been extensively revised not only to include all aspects of oral surgery but also to reflect the changes in maxillofacial practice that have occurred since 1998. In particular, the role of osseointegrated implants, the management of craniofacial trauma and facial aesthetic surgery including 'cosmetic' surgery and bone distraction have all moved on since the first edition was written. The editors have made a careful selection of contributors representing current practice from throughout the world including continental Europe, the United States, Asia and Australia. Operative Oral and Maxillofacial Surgery represents international best practice in the specialty. Each chapter has been written by an internationally recognised expert and represents a 'how I do it' master class. It is illustrated with clear line diagrams supplemented where appropriate with clinical photographs showing the essential steps in all the surgical procedures in current clinical practice. Authors have kept to a standard template, ensuring a minimum of discussion and an emphasis on surgical technique.The definitive surgical manual in the field, Operative Oral and Maxillofacial Surgery will appeal to trainees, young specialists and established experts not only in oral and maxillofacial surgery but also the related specialties of otorhinolaryngology and plastic surgery.

O DROPEREALFRED. "Opere A.O., Mkhandi S.H. and P. Willems (2006): At Site Food Frequency Analysis for the Nile Equatorial basins. Journal of Physics and Chemistry of the Earth 31 (2006) 919.". In: Vulnerability to Climate-Induced Highland Malaria in East AIACC Working Paper No.25; 47pp. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2006. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A. (2005): Hazard Risk assessment in Mount Kenya headwaters: Sustainable Management of Headwater Resources; research from Africa and India, United Nations University, p165-177; Jansky L., Martin J. Haigh and H. Prasad (eds).". In: Proc. 7th Kenya Meteorological Society Workshop on Meteorological Research, Applications and Services, Nairobi, 17-21 0ctober 2005. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2005. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2000): The need for a flood forecasting system (FFS) in Kenya Proceedings of the Fifth workshop of the Kenya Meteorological Society workshop on Meteorological Research, Applications and Services, 4-8 September 2000, Mombasa, Kenya.". In: Journal of African Meteorological Society, vol.15, 2001. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2000. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2002): Climate data and GCM models Report of the af_91 AIACC Project workshop held at Sunset hotel, Kisumu, 2nd .". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2002): Homogeneous climatologic zones using principal component analysis. Proceedings of pre-forum capacity building training workshop for the Great Horn of Africa (GHA), 20th January to 17th February 2002.". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2002): Impacts of climate change in water resources planning and management. Proceedings of the 9th Nile 2002 International conference, Kenya College of Communications and Technology (KCCT), Nairobi, 7-9 October 2002.". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2002): Lessons from the 1997/98 Elnino floods and the 2000 La nina related drought. Proceedings of the capacity building training workshop on stream flow modeling for the Great Horn of Africa (GHA), 4th .". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. (2002): Quality control of rainfall data Proceedings of pre-forum capacity building training workshop for the Great Horn of Africa (GHA), 20th January to 17th February, 2002, Nairobi, Kenya.". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O. and mutua, F.M. (1996): Transfer-Function model for Upper Athi river catchment of central Kenya. Proceedings of the 3rd workshop of the Kenya Meteorological Society workshop on Meteorological Research, Applications and Services, 7-11 October 1.". In: Journal of African Meteorological Society, vol.15, 2001. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 1996. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Awuor, V.O., Kooke, S.O. and W.O. Omoto (2002): Impact of rainfall variability on water resource management. Proceedings of the 3rd WaterNet/Warfsa Symposium, WhiteSands Hotel, Dar-es-Salaam, Tanzania, 30-31 October 2002.". In: Journal of African Meteorological Society, March 2002. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2002. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Awuor, V.O., Kooke, S.O. and W.O. Omoto (2003): Impact of rainfall variability on water resources management: case study in Kitui district, Kenya. Proceedings of JACs East Africa Workshop: Silver Springs Hotel, Nairobi, Kenya, 15 May 2003.". In: Journal of African Meteorological Society, vol.6.no1, (2003). A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2003. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Mkhandi S., Willems, P. (2005): At site flood frequency analysis for the Nile equatorial basins. Proceedings of the International conference of FRIEND/Nile FUST project, Sheraton Sharm Hotel, Sharm El Sheik, Egypt.". In: Proc. 7th Kenya Meteorological Society Workshop on Meteorological Research, Applications and Services, Nairobi, 17-21 0ctober 2005. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2005. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Mkhandi S., Willems, P. (2005): Homogeneity testing for peak flow in catchments in the equatorial Nile basins. Proceedings of the International conference of FRIEND/Nile FUST project, Sheraton Sharm Hotel, Sharm El Sheik, Egypt.". In: Proc. 7th Kenya Meteorological Society Workshop on Meteorological Research, Applications and Services, Nairobi, 17-21 0ctober 2005. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 2005. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Mutua, F.M. and L.A. Ogallo (1993): Catchment spatial characteristics derived from principal component analysis (PCA). Proceedings of the First International workshop for the African Meteorological Society, 8-12 February 1993, KICC, Nairobi, .". In: Journal of African Meteorological Society, vol.15, 2001. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 1993. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
O DROPEREALFRED. "Opere, A.O., Mutua, F.M. and L.A. Ogallo (1998): Regional flood frequency analysis. Proceedings of the Fourth workshop of the Kenya Meteorological Society workshop on Meteorological Research, Applications and Services, 7-11 September 1998, Mombasa, Kenya.". In: Journal of African Meteorological Society, vol.15, 2001. A Matimba, M Oluka, B Ebeshi, J Sayi, Bolaji, J Del Favero , C Van Broeckhoven, AN Guanta; 1998. Abstract
Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.
M DRNJOKAHJOSEPHM. "Ophalocele management in Kenyatta National Hospital,Medcom(under print) 2002.". In: Faculty of Veterinary Medicine Biennial Conference. 2004 Kabete Nairobi. au-ibar; 2002. Abstract
   
Dean WH, Buchan JC, Gichuhi S, Faal H, Mpyet C, Resnikoff S, Gordon I, Matende I, Samuel A, Visser L, Burton MJ. "Ophthalmology training in sub-Saharan Africa: a scoping review." Eye (Lond). 2021;35(4):1066-1083. AbstractWebsite

Sub-Saharan Africa is home to 12% of the global population, and 4.3 million are blind and over 15 million are visually impaired. There are only 2.5 ophthalmologists per million people in SSA. Training of ophthalmologists is critical. We designed a systematic literature review protocol, searched MEDLINE Ovid and Embase OVID on 1 August 2019 and limited these searches to the year 2000 onwards. We also searched Google Scholar and websites of ophthalmic institutions for additional information. We include a total of 49 references in this review and used a narrative approach to synthesise the results. There are 56 training institutions for ophthalmologists in eleven Anglophone, eleven Francophone, and two Lusophone SSA countries. The median duration of ophthalmology training programmes was 4 years. Most curricula have been regionally standardised. National, regional and international collaborations are a key feature to ophthalmology training in more than half of ophthalmology training programmes. There is a drive, although perhaps not always evidence-based, for sub-specialisation in the region. Available published scientific data on ophthalmic medical and surgical training in SSA is sparse, especially for Francophone and Lusophone countries. However, through a broad scoping review strategy it has been possible to obtain a valuable and detailed view of ophthalmology training in SSA. Training of ophthalmologists is a complex and multi-faceted task. There are challenges in appropriate selection, capacity, and funding of available training institutions. Numerous learning outcomes demand curriculum, time, faculty, support, and appropriate assessment. There are opportunities provided by modern training approaches. Partnership is key.

SAMSON PROFMEMEJULIUS. "Opinya G., Kaimenyi JT., Meme JS., Oral Findings in Faconi's Anaemia. J. Peiodontol 59:473, 1988.". In: J. Peiodontol 59:473, 1988. au-ibar; 1988. Abstract

A case of fanconi's anemia was referred to the Dental School from the Department of Pediatrics. The patient was a 24-year-old male and a product of a consanguineous marriage. His chief complaint was loose and falling teeth, which has started at the age of 16 years. The first teeth to fall out were the first permanent molars followed by mandibular and maxillary anteriors. General examination showed that the patient was of normal intelligence and small for his age. He had no palmar plantar hyperkeratosis and was not diabetic. A total of 19 teeth remained in the mouth, most of them with grade three mobility. The remaining molars and first maxillary premolars had grade three furcation involvement. Most of the teeth had periodontal pockets more than 10 mm deep. Full mouth intraoral periapical radiographs and orthopantomographic views showed severe horizontal bone loss uncommensurate with the patient's age. In view of the patient's history and severe bone loss at an early age, the diagnosis was juvenile periodontitis associated with Fanconi's anemia.

T. PROFKAIMENYIJACOB. "Opinya G.N., Kaimenyi, J.T and Meme J.S. (1988). Oral findings in Fanconi.". In: J Periodontol. 1988 Jul;59(7):461-3. African Meteorological Society; 1988. Abstract

Dental School, College of Health Sciences, Nairobi, Kenya, Africa. A case of fanconi's anemia was referred to the Dental School from the Department of Pediatrics. The patient was a 24-year-old male and a product of a consanguineous marriage. His chief complaint was loose and falling teeth, which has started at the age of 16 years. The first teeth to fall out were the first permanent molars followed by mandibular and maxillary anteriors. General examination showed that the patient was of normal intelligence and small for his age. He had no palmar plantar hyperkeratosis and was not diabetic. A total of 19 teeth remained in the mouth, most of them with grade three mobility. The remaining molars and first maxillary premolars had grade three furcation involvement. Most of the teeth had periodontal pockets more than 10 mm deep. Full mouth intraoral periapical radiographs and orthopantomographic views showed severe horizontal bone loss uncommensurate with the patient's age. In view of the patient's history and severe bone loss at an early age, the diagnosis was juvenile periodontitis associated with Fanconi's anemia.

SAMSON PROFMEMEJULIUS. "Opinya GN, Kaimenyi JT, Meme JS.Oral findings in Fanconi's anemia. A case report.J Periodontol. 1988 Jul;59(7):461-3.". In: J Periodontol. 1988 Jul;59(7):461-3. au-ibar; 1988. Abstractoral_findings_in_fanconi.pdf

A case of fanconi's anemia was referred to the Dental School from the Department of Pediatrics. The patient was a 24-year-old male and a product of a consanguineous marriage. His chief complaint was loose and falling teeth, which has started at the age of 16 years. The first teeth to fall out were the first permanent molars followed by mandibular and maxillary anteriors. General examination showed that the patient was of normal intelligence and small for his age. He had no palmar plantar hyperkeratosis and was not diabetic. A total of 19 teeth remained in the mouth, most of them with grade three mobility. The remaining molars and first maxillary premolars had grade three furcation involvement. Most of the teeth had periodontal pockets more than 10 mm deep. Full mouth intraoral periapical radiographs and orthopantomographic views showed severe horizontal bone loss uncommensurate with the patient's age. In view of the patient's history and severe bone loss at an early age, the diagnosis was juvenile periodontitis associated with Fanconi's anemia.

T. PROFKAIMENYIJACOB. "Opinya GN, Kaimenyi JT, Meme JS.Oral findings in Fanconi's anemia. A case report.J Periodontol. 1988 Jul;59(7):461-3.". In: J Periodontol. 1988 Jul;59(7):461-3. African Meteorological Society; 1988. Abstract

A case of fanconi's anemia was referred to the Dental School from the Department of Pediatrics. The patient was a 24-year-old male and a product of a consanguineous marriage. His chief complaint was loose and falling teeth, which has started at the age of 16 years. The first teeth to fall out were the first permanent molars followed by mandibular and maxillary anteriors. General examination showed that the patient was of normal intelligence and small for his age. He had no palmar plantar hyperkeratosis and was not diabetic. A total of 19 teeth remained in the mouth, most of them with grade three mobility. The remaining molars and first maxillary premolars had grade three furcation involvement. Most of the teeth had periodontal pockets more than 10 mm deep. Full mouth intraoral periapical radiographs and orthopantomographic views showed severe horizontal bone loss uncommensurate with the patient's age. In view of the patient's history and severe bone loss at an early age, the diagnosis was juvenile periodontitis associated with Fanconi's anemia.

OPIYO PROFAKECHNOBERT. "Opiyo -Akech, N - Tectono -Magmatic emplacement of the Kenyan Granite Greenstones: Geochemical evidence from the Maseno area, western Kenya.". In: African Journal of Science and Technology, Vol.6 No.2 pp27 -33. UNIVERSITY OF NAIROBI; 1992. Abstract
n/a
OPIYO PROFAKECHNOBERT. "Opiyo -Akech, N and J. O. Barongo (1999): Earth Science Education In Kenya.". In: Journal of African Earth Sciences. Vol.28 No.4 pp795 -803. UNIVERSITY OF NAIROBI; 1999. Abstract
n/a
OPIYO PROFAKECHNOBERT. "Opiyo -Akech, N, J. Tarney and Hoshino, M (1999): Petrology and geochemistry of granites from the Archaean terrain north of Lake Victoria, Western Kenya.". In: Journal of African Earth Sciences. Vol.29 No.2 pp283 -300. UNIVERSITY OF NAIROBI; 1999. Abstract
n/a
O DROGARAWILLIAM. "Opiyo A T, W O Ogara 2000. Public health evaluation of existing animal waste handling methods. In: The veterinary profession in a changing environment, Kenya veterinary Vol. 24 115-120.". In: journal. The Kenya Veterinarian; 2000. Abstract
As part of a study to assess zoonotic milk-borne health risks, seasonal survey data and unpasteurized milk samples were collected between January 1999 and February 2000 from randomly selected informal milk market agents (220 and 236 samples in the dry and wet seasons, respectively) and from households purchasing raw milk (213 and 219 samples in the dry and wet seasons, respectively) in rural and urban locations in Central Kenya and screened for antibiotics, Brucella abortus (B. abortus) and presence of Escherichia coli (E. coli 0157:H7).The latter was assessed based on samples from consumer households only. Antibodies to B. abortus were screened using the indirect antibody Enzyme Linked Immunosorbent Assay (ELISA) and the Milk Ring Test (MRT). The presence of E. coli 0157:H7 was assessed by culture, biochemical characterization, serological testing for production of verocytotoxin one (VTI) and two (VT2) and polymerase chain reaction (PCR) analysis for the presence of genes encoding for the toxins.                                                                                                         The prevalence of antibodies to B.abortus varied considerably ranging from none in milk sold in small units and originating from intensive production systems to over 10% in samples that were bulked or originating from extensive production systems. E. coli 0157:H7 was isolated from two samples (0.8%), one of which produced VTI. All urban consumers (100%) and nearly all rural consumers (96%) of marketed milk boiled the milk before consumption, mainly in tea, thus reducing chances of exposure to live pathogens and potential health risks.
O MROPIYOELISHATOYNE. "Opiyo E.T.O. (1995). A case-based problem solving strategy: sembe im ipimo gi nyamin.". In: Kenya's first national information technology (IT) conference and exhibition, 29th November - 2nd December, 1995, KICC, Nairobi. UNIVERSITY OF NAIROBI; 1995.
O MROPIYOELISHATOYNE. "Opiyo E.T.O. (1995). Reflections on expert systems for developing countries.". In: Kenya's first national information technology(IT) conference and exhibition, 29th November - 2nd December, 1995, KICC, Nairobi. UNIVERSITY OF NAIROBI; 1995.
O MROPIYOELISHATOYNE. "Opiyo Elisha T. O. and Erick Ayienga, Katherine Getao, Bernard Manderick, Okello-Odongo, Ann Now.". In: In the Proceedings of The Fourth International 4th Annual International Conference on Computing and Research- SREC08, Makerere University, Uganda, 3-6 August, 2008. UNIVERSITY OF NAIROBI; 2008.
O MROPIYOELISHATOYNE. "Opiyo Elisha T. O., Erick Ayienga and Katherine Getao, Bernard Manderick, and Okello-Odongo and Ann Now.". In: In the Proceedings of the first International Conference in Computer Science and Informatics, School of Computing and Informatics, University of Nairobi, Kenya, 5-9 February, 2007. UNIVERSITY OF NAIROBI; 2007.
O MROPIYOELISHATOYNE. "Opiyo Elisha T. O., Erick Ayienga, Katherine Getao, Bernard Manderick, Okello- Odongo, Ann Now.". In: In Proceedings of the International Conference on Research for Sustainable Development and Institutional Capacity Building. UNIVERSITY OF NAIROBI; 2009.
"Opiyo Elisha T. O., Erick Ayienga, Katherine Getao, Bernard Manderick, Okello-Odongo, Ann Now.". In: { In the Proceedings of The Fourth International 4th Annual International Conference on Computing and Research- SREC08}, Makerere University, Uganda, 3-6 August, 2008.; 2005. Abstract

n/a

O MROPIYOELISHATOYNE. "Opiyo Elisha T. O., Erick Ayienga, Katherine Getao, Bernard Manderick, Okello-Odongo, Ann Now.". In: In Proceedings of the 4th International Operations Research Society of East Africa (ORSEA) Conference, 23rd-24th Oct 2008, Nairobi, Kenya. UNIVERSITY OF NAIROBI; 2008.
O MROPIYOELISHATOYNE. "Opiyo, Elisha T. O. (1995). Case-based reasoning for expertise relocation in support of rural health workers in developing countries.". In: In Manuela Veloso, Agnar Aamodt (Editors), Case- Based Reasoning Research and Development, First International Conference, ICCBR-95, Sesimbra, Portugal, October 1995, Proceedings. Springer -Verlag. UNIVERSITY OF NAIROBI; 1995.
DR. MUKABANA WOLFANGRICHARD. "Opiyo, P., Mukabana, W.R., Kiche, I.O., Mathenge, E.M., Killeen, G.F., Fillinger, U., 2007, An exploratory study of community factors relevant for participatory malaria control on Rusinga Island, western Kenya. Malaria Journal, 6: 48.". In: Malaria Journal, 6: 48. Journal of School of Continuous and Distance Education ; 2007. Abstract
Normal 0 false false false MicrosoftInternetExplorer4 st1:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Capacity strengthening of rural communities, and the various actors that support them, is needed to enable them to lead their own malaria control programmes. Here the existing capacity of a rural community in western Kenya was evaluated in preparation for a larger intervention. Focus group discussions and semi-structured individual interviews were carried out in 1,451 households to determine (1) demographics of respondent and household; (2) socio-economic status of the household; (3) knowledge and beliefs about malaria (symptoms, prevention methods, mosquito life cycle); (4) typical practices used for malaria prevention; (5) the treatment-seeking behaviour and household expenditure for malaria treatment; and (6) the willingness to prepare and implement community-based vector control. Malaria was considered a major threat to life but relevant knowledge was a chimera of scientific knowledge and traditional beliefs, which combined with socio-economic circumstances, leads to ineffective malaria prevention. The actual malaria prevention behaviour practiced by community members differed significantly from methods known to the respondents. Beside bednet use, the major interventions implemented were bush clearing and various hygienic measures, even though these are ineffective for malaria prevention. Encouragingly, most respondents believed malaria could be controlled and were willing to contribute to a community-based malaria control program but felt they needed outside assistance. Culturally sensitive but evidence-based education interventions, utilizing participatory tools, are urgently required which consider traditional beliefs and enable understanding of causal connections between mosquito ecology, parasite transmission and the diagnosis, treatment and prevention of disease. Community-based organizations and schools need to be equipped with knowledge through partnerships with national and international research and tertiary education institutions so that evidence-based research can be applied at the grassroots level.
OPIYO PROFAKECHNOBERT. "Opiyo-Akech, N. - Geochemistry of the Archaean Greenstone Volcanics from the area around Maseno, western Kenya.". In: Nairobi University Geological Magazine. Vol. 1 pp42-47. UNIVERSITY OF NAIROBI; 1990. Abstract
n/a
W DRICHANGIDANIEL. "Opiyo-Akech, N., Tarney, J. and Ichang.". In: Geological Society of South Africa Annual Meeting 24th. June, 1999. Abstract. Philosophical Issues Invoked by Shona People; 1999. Abstract
.
OPONDO MARY. "Opondo, M., and Wendoh, S., (2006).". In: (EAMJ 82: 592-597). University of Nairobi.; 2006. Abstract

Four hundred and forty-six children attending nursery schools in Nairobi were examined for caries and gingivitis. Assessment of social class was based on the occupation of the head of the child's household. Amongst 3-year-old children, 62% were caries-free and the mean dmft was 1.35. Amongst 5-year-olds 50% were caries-free and the mean dmft was 1.88. Thirty-seven per cent of the children had evidence of gingivitis, with the proportion changing little with age. There was no evidence of either caries or gingivitis being significantly related to social class, although children in the higher classes had more filled teeth.

OPONDO MARY. "Opondo, M., Dolan, C.S., Wendoh, S., and Kathuri, J.". In: (EAMJ 82: 592-597). University of Nairobi.; 2007. Abstract

Four hundred and forty-six children attending nursery schools in Nairobi were examined for caries and gingivitis. Assessment of social class was based on the occupation of the head of the child's household. Amongst 3-year-old children, 62% were caries-free and the mean dmft was 1.35. Amongst 5-year-olds 50% were caries-free and the mean dmft was 1.88. Thirty-seven per cent of the children had evidence of gingivitis, with the proportion changing little with age. There was no evidence of either caries or gingivitis being significantly related to social class, although children in the higher classes had more filled teeth.

Njeri KM, Khayes M. "Opportuities in the Matatu Services.". In: Rembering Kenya Vol. 2. Nairobi: Twaweza Limited; 2013.
Ongoro TN. "Opportunities and Challenges For Foreign Direct Investment in Africa in the era of Global Financial Crisis." Eurasian International Scientific-Analytical Journal. Forthcoming.
Verdoodt A;, Moussandek R;, Mureithi SM;, Vermang, J.; Ye L. "Opportunities and challenges in assessing and combating land degradation.".; 2012. Abstract

Technology development for assessing and combating land degradation faces various challenges, both
in high and low income countries. This paper aims to highlight knowledge gaps on spatio-temporal
soil functioning and on efficiency of soil conservation measures: (1) “What are current challenges
related to assessing land degradation?”, (2) “What do we know about the impact of land degradation
on food security?”, and (3) “What is the efficiency of conservation measures?”. The discussion
encompasses soil degradation at field plot to continental scale, as well as bottlenecks relevant to both
low and high-income countries. Key issues identified within each theme are illustrated using a number
of case studies. They illustrate the need for innovative approaches to systematic assessments of the
dynamic nature of soil functioning and degradation, of the impact of soil degradation on various
ecosystem services, to support the identification and design of suitable soil management, soil
conservation or soil improvement measures. Experimental trials and process-based models reflecting
ecosystem functioning, though highly time and data demanding, are still needed to pursue better local
insights and feed process-based land degradation models applied at watershed scale.

"Opportunities and Challenges of China-Africa Aid Relations’." African Journal of Economics Policy. 2009;16(2).
Paul Kamau. "Opportunities and Challenges of the Multilateral Trading System: The Kenyan Experience under WTO." Institute for International Studies) Vol. 37 Number 1, pp. 101-116; 2004. Abstract
n/a
Gausset Q, Andersen SK, Hansen HH, Lund JF, Mugasha AG, Nathan I, Theilade I. "Opportunities and constraints for private and communal tree management in Majawanga (Gairo, Tanzania).". 2007.
Karani PF. "Opportunities and Constraints in teacher training.". In: Coordination of primary teacher training and University education. Multimedia University of Kenya, Mbagathi, Nairobi.; 2009.
A PKARANIFLORIDA. "Opportunities and Constraints in teacher training: Primary versus Secondary Education levels.". In: Consultative Workshop on Coordination of primary teacher training and University education.; 2009.
Scholtz MM, McManus C, Okeyo AM. "Opportunities for beef production in developing countries of the southern hemisphere.". 2011. Abstract

Developing countries from the southern hemisphere have similarities in terms of climatic and agricultural conditions and cattle are the most important livestock species in these countries — which leads to many areas of similar interest and opportunities regarding beef cattle production. The increase in demand for meat in developing countries offers large market opportunities for livestock producers. If the productivity of beef farmers can be improved to commercial levels, it may have the potential to address poverty in these agriculturally based economies. Climate change is predicted to be highly dynamic and can have adverse effects on crop and livestock productivity. The cattle breed to be used and the production strategy to be followed in developing countries of the southern hemisphere will depend primarily on the environment and level of management. The availability of diverse cattle breed resources with adaptive and productive differences will allow breed types to be matched to different environments, management capabilities and markets. In the harsh and undeveloped areas or pastoralist systems, pure breeding with e.g. Sanga, Zebu or naturalized breeds may be the only production strategy that can be followed. In the more developed areas, crossbreeding with small indigenous cows may succeed in improving the output of beef cattle farming. It is believed that crossbreeding will gain importance in many developing counties in the southern hemisphere. It is therefore essential that crossbreeding studies be conducted where necessary, to supply information regarding heterosis and for the development of multi-breed genetic evaluations, breeding objectives and decision making. By describing production environments it may be possible to identify genotypes that are adapted to a specific environment. However, tools are needed to overlay geo-referenced data sets onto the different environments. Statistical science continues to support animal breeding and improvement, especially with respect to production traits. Traits linked to fertility and/or survival are still problematic and the appropriate quantitative breeding technology to properly handle these traits still needs to be developed. Gene or marker assisted selection may play an important role in selection for disease and parasite resistance or tolerance, since it is generally difficult to measure these traits directly. Strategies that utilize EBVs derived from genomic analyses (genomic EBVs), together with conventional mixed model methodology, may speed up the process of breeding animals with subsequent higher and more efficient production. The application of a landscape genetics approach offers the potential to greatly enhance the knowledge of how landscape heterogeneity influences the genetic population structure, gene flow, and adaptation. Results from these studies can be used to address questions related to species management and conservation.

M PROFSYAGGAPAUL. "Opportunities in a falling market: what has been happening at the low end of the urban land market.". In: Urban LandMark Conference,South Africa. Urban LandMark; 2009. Abstract
Falling land and property prices which have been experience globally since 2008,present both a challenge and an opportunity.What opportunities does such a market present to government,the private sector and to communities trying to establish themselves in urban areas? The myth is that such opportunities would assist the poor, but the reality is that the prices are already too high to be within the reach of the poor.Irrespective of how low they fall,short of affirmative action through grants,cross subsidies and other innovative approaches falling prices remain a pipe dream for the urban poor..
JAMES PROFODEK. "Opportunities of the Lome Convention for the East African Economy; Friedrich Ebert Stiftung, april Nairobi.". In: Paper presented at the WIPO High Level Forum on IP Policy and Strategy, Tokyo . Prof. James Otieno-Odek; 1998. Abstract
J. O. Midiwo, A. Yenesew, B. F. Juma, S. Dereses, J. A. Ayoo, A. Aluoch and S. Guchu There are several described medicinal plants in Kenya from a flora of approximately 10,000 members. Strong cross-medical information from the 42 ethnic groups points to the high potential of some of these species. The Myrsinaceae are well established ethno-anthelmintics and anti-bacterials. They are harbingers of long alkyl side chain benzoquinones which clearly have a protective function from their histochemical disposition. The main benzoquinone in the sub-family Myrsinodae is embelin while for the Maesodae it is maesaquinone together with its 5-acetyl derivative; the distribution of these benzoquinones by their alkyl side chain length or the presence/absence of a 6-methyl group is in accord with morphological sub-family de-limitation. The benzoquinones showed anti-feedant, anti-microbial, phytotoxic, acaricidal, insecticidal and nematicidal activity. Many other benzoquinones of medium and minor concentration were also isolated and characterised. Some plants belonging to the Polygonaceae which are widely used as ethno-anthelmintics have been studied. The common anthelmintic anthraquinones were obtained from all five Rumex species while the naphthalenic acetogenin derivative, nepodin was more selectively distributed. The leaf of Polygonum senegalense is up to 17% surface exudate; about thirteen non polar flavonoid derivatives (chalcones, dihydrochalcones, flavanones and a flavone) have been isolated from it. From the internal aerial tissues of this plant, the major flavonoids were common flavonoids, quercetin, kaempferol, luteolin and their glycosides. The only unique compound isolated from this plant was 2prime-glucosyl-6prime-hydroxy-4prime-methoxydihydrochalcone whose aglycone, uvangolatin is part of the exudate mixture. Other leaf exudate plants studied include the stomach-ache medicine, Psiadia punctulata (Compositae) from which novel methylated flavonoids, kaurene and trachyloban diterpenes have been found
Duysburgh E, Kerstens B, Kouanda S, Kaboré CP, Belemsaga Yugbare D, P G, Masache G, Crahay B, Gondola Sitefane G, Bique Osman N, Foia S, Barros H, Castro Lopes S, Mann S, Nambiar B, Colbourn T, M. T. "Opportunities to improve postpartum care for mothers and infants: design of context-specific packages of postpartum interventions in rural districts in four sub-Saharan African countries." BMC Pregnancy Childbirth.. 2015;3;15:131. (doi: 10.1186/s12884-015-0562-8. ).
Tsuma VT, Magnusson U. "Opsonic activity in mammary secretion and serum of gilts during the lactation period.". 1992. Abstract

Opsonic activity was studied in mammary secretion and serum during lactation in four healthy gilts. The opsonic activity was determined as peak chemiluminescence and time to peak chemiluminescence in a luminol enhanced chemiluminescence assay. The peak chemiluminescence was significantly (p < 0.05) higher in mammary secretion around parturition than later in lactation. No changes in the opsonic activity were seen in serum during lactation. Overall, the peak chemiluminescence and time to peak chemiluminescence were significantly higher (p < 0.001) and shorter (p < 0.05) respectively, in serum than in mammary secretion. The present study indicates that the opsonic activity is highest in mammary secretion around parturition but decreases later in lactation, and that this change is confined to the mammary gland.

Muiva CM, Mwabora JM. "Optical and Dielectric properties of Amorphous ternary Se90-xIn10Sbx thin films,." Journal of Alloys and Compounds. 2016;689:432-438. Abstract

Ternary thin film alloys of Se90-XIn10SbX (x = 1, 4, 10, 15 and 20) were synthesized by flash evaporation of the pre-melt quenched bulk samples under a vacuum of 10-5 Torr. Optical absorption analysis pointed to indirect allowed transitions as the mechanism of excitation across the energy gap. The optical band gap (Eg) was evaluated on the basis of Wemple-Didomenico single oscillator model and Tauc's extrapolation method in the spectral region where the absorption coefficient, α ≥ 104 cm-1. The refractive index (n), complex dielectric constant (ε), band tailing parameter (B), plasma frequency (ωp), single oscillator parameters (Eo and Ed) and lattice dielectric constant (εL) were deduced for each alloy. The compositional dependence of optical and dielectric parameters was explained on the basis of chemical bond approach. The observed shift in the trends of Eg, Ed, εL and up values at the composition where Sb = 4 at% was correlated to the usual chemical threshold at this composition.

Muthoka B, Mwabora JM, Domtau DL, Simiyu J, Ayieta EO. "Optical and Electrical Properties Dependence on Thickness of Screen-Printed TiO2 Thin Films." Journal of Materials Physics and Chemistry. 2016. Abstract

Effect of film thickness on the optical and electrical properties of TiO 2 thin films were
studied. Thin films of different thicknesses were deposited by screen printing method on
fluorine doped tin oxide coated on glass substrate. The film thickness was determined by
surface profile measurement. The thicknesses were 3.2, 8.2, 13.5 and 18.9 µm.
Transmittance, reflectance and absorbance spectra were studied using UV-VIS-NIR
spectrophotometer in the photon wavelength range of 300-1500 nm for transmittance and …

Domtau DL, Simiyu J, Muthoka B, Mwabora J. "Optical and Electrical Properties Dependence on Thickness of Screen-Printed TiO2 Thin Films. ." Journal of Materials Physics and Chemistry. . 2016;4(1):1-3.
Domtau DL, Simiyu J, Ayieta EO, Muthoka B, Mwabora JM. "Optical and Electrical Properties Dependence on Thickness of Screen-Printed TiO2 Thin Films." Journal of Materials Physics and Chemistry.. 2016;4(1):1. Abstract

Effect of film thickness on the optical and electrical properties of TiO2 thin films was studied. Thin films of different thicknesses were deposited by screen printing method on fluorine doped tin oxide coated on glass substrate. The film thickness was determined by surface profile measurement. The thicknesses were 3.2, 8.2, 13.5 and 18.9 µm. Transmittance, reflectance and absorbance spectra were studied using UV-VIS-NIR spectrophotometer in the photon wavelength range of 200-2500 nm for transmittance and reflectance and 200-1200 nm for absorbance. Band gap and refractive index of the films were determined using these spectra. It was found that reflectance, absorbance, band gap and refractive index increase with film thickness while transmittance decreases with increase in thickness. I-V characteristics of the films were also measured by a 4- point probe. Electrical resistivity (

Optical and Electrical Properties of Magnesium Doped Zinc Oxide for Photovoltaic Applications. United Kenya Club; 2013. Abstract

This research is an experimental design which came up with the optical and electrical properties of magnesium doped zinc oxide for photovoltaic applications. The specific objectives are to determine the Optical properties, and electrical properties of Magnesium doped ZnO of Magnesium doped ZnO. These objectives are to be achieved by sputtering three types of targets on to glass slides. The targets that will be used are two targets of magnesium doped ZnO with compositions of ZnO: Mg being 95:5 wt% and 90:10 wt%, both with a purity of 99.99% and a third target of un-doped ZnO with a purity of 99.99% . The optical properties will be determined using a double beam spectrophotometer in the UV/VIS/NIR regions. Thus the absorption, transmission and reflection properties will be focused on. The electrical properties will be determined using four point probe and the film resistance, sheet resistance and film conductivity will be looked at.

Mugwang’a FK, Karimi PK, Njoroge WK, Omayio O, Waita SM. "Optical Characterization of Copper Oxide Thin Films Prepared By Reactive Dc Magnetron Sputtering For Solar Cell Applications.". 2012. AbstractOptical Characterization of Copper Oxide Thin Films Prepared By Reactive Dc Magnetron Sputtering For Solar Cell Applications

— Cu2O thin films have been deposited using reactive dc magnetron sputtering technique using an Edward Auto 306 Magnetron Sputtering System. Transmittance and reflectance data in the range 300 nm-2500 nm were obtained using UV-VIS NIR Spectrophotometer Solid State 3700 DUV for all the thin films samples that were prepared. Transmittance values of above 70% were observed. The optical measurements were simulated using SCOUT 98 software to determine optical constants and optical bad gap of the thin. The optical properties in these films were varied by varying oxygen flow rate at constant powerof 200 W. Optical studies show a direct allowed transition and a shift in the optical absorption edge as the oxygen flow rate varies at constant argon flow rate and other deposition parameters. These results show that single phase Cu2O thin films can be synthesized at a relatively low substrate temperature using the reactive dc magnetron sputtering technique. Band gap values of 1.62 eV –2.54 eV is observed. The surface sheet resistivities at room temperature of 298 K were found to vary with the deposition parameters and film thickness. Urbach energy varied between 0.6 ×10-4 to 1.92 ×104

and S. M. Waita, B. O. Aduda MNJMGA. Optical Characterization of sputtered TiO2 compact layers for dye-sensitized solar cell applications. 13-15 October 2009, Dar es Salaam, Tanzania; 2009.

UoN Websites Search