University of Nairobi

About: University of Nairobi is a education organization based out in Nairobi, Nairobi, Kenya. It is known for research contribution in the topics: Population & Health care. The organization has 6702 authors who have published 10777 publications receiving 231294 citations. The organization is also known as: UoN & IAU-020319.

The effects of dark rearing on the development of the visual cortex of the rat

Abstract: The effects of dark rearing on the development of the visual cortex has been studied in Wistar rats, as have the effects of subsequent light exposure on recovery Five groups of animals were used: (1) light exposed until 30-40 days post partum (dpp) (2) dark reared until 30-40 dpp (3) dark reared until 80-120 dpp (4) dark reared to 21 dpp, then light exposed until 40 dpp (5) light exposed to 21 dpp and then dark reared until 40 dpp Golgi-Cox impregnations of layer IV stellate cell dendritic fields were analysed and total neuronal and glial counts were also done within layer IV of the primary visual cortex Normal visual stellate cell dendritic fields were radially organised, with the highest dendritic density being recorded below the soma In short term visually deprived animals and in those exposed only for 21 dpp and then reared in light until 40 dpp the radial distribution of dendrites was maintained but the peak density shifted to above the soma In all other experimental groups this abnormal polarisation was still present but not as marked Measurement of branching indices suggested that these field changes resulted from increased branching and growth in the superficial domain and not from the reorientation of dendrites Differential glial counts revealed a significantly higher number of microglia in dark reared animals than in controls Neuronal numbers were not affected

Toxigenic potential of Aspergillus species occurring on maize kernels from two agro-ecological zones in Kenya.

Abstract: Two agro-ecological zones in Kenya were selected to compare the distribution in maize of Aspergillus spp. and their toxigenicity. These were Nandi County, which is the main maize growing region in the country but where no human aflatoxicoses have been reported, and Makueni County where most of the aflatoxicosis cases have occurred. Two hundred and fifty-five households were sampled in Nandi and 258 in Makueni, and Aspergillus was isolated from maize. Aspergillus flavus and A. parasiticus isolates were tested for the presence of aflD and aflQ genes. Positive strains were induced to produce aflatoxins on yeast extract sucrose and quantified using liquid chromatography-tandem mass spectrometry (LCMSMS). Aspergillus flavus was the most common contaminant, and the incidence of occurrence in Nandi and Makueni was not significantly different (82.33% and 73.26%, respectively). Toxigenic strains were more prevalent than non-toxigenic strains. All the toxigenic strains from Makueni were of the S-type while those from Nandi belonged to the l-type. Quantitative differences in aflatoxin production in vitro between isolates and between strains were detected with S strains producing relatively larger amounts of total aflatoxins, B toxins and lower values for G toxins. This was in accord with the frequent aflatoxicosis outbreaks in Makueni. However some L strains produced considerable amounts of B toxins. Given the widespread distribution of toxigenic strains in both regions, the risk of aflatoxin poisoning is high when favorable conditions for toxin production occur.

Domestic violence and prevention of mother-to-child transmission of HIV-1.

Abstract: OBJECTIVES To determine the prevalence of life-time domestic violence by the current partner before HIV-1 testing, its impact on the uptake of prevention of mother-to-child transmission (PMTCT) interventions and frequency after testing DESIGN A prospective cohort METHODS Antenatally, women and their partners were interviewed regarding physical, financial, and psychological abuse by the male partner before HIV-1 testing and 2 weeks after receiving results RESULTS Before testing, 804 of 2836 women (28%) reported previous domestic violence, which tended to be associated with increased odds of HIV-1 infection [univariate odds ratio (OR) 17, 95% confidence interval (CI) 13-22; P < 00001, adjusted OR 12, 95% CI 09-16; P = 01], decreased odds of coming with partners for counseling (adjusted OR 07, 95% CI 05-10; P = 004), and decreased odds of partner notification (adjusted OR 07, 95% CI 05-11; P = 009) Previous domestic violence was not associated with a reduced uptake of HIV-1 counseling, HIV-1 testing, or nevirapine After receiving results, 15 out of 1638 women (09%) reported domestic violence After notifying partners of results, the odds of HIV-1-seropositive women reporting domestic violence were 48 times those of HIV-1-seronegative women (95% CI 14-16; P = 001) Compared with women, men reported similar or more male-perpetrated domestic violence, suggesting a cultural acceptability of violence CONCLUSION Domestic violence before testing may limit partner involvement in PMTCT Although infrequent, immediate post-test domestic violence is more common among HIV-1-infected than uninfected women Domestic violence prevention programmes need to be integrated into PMTCT, particularly for HIV-1-seropositive women

Subtype C Is associated with increased vaginal shedding of HIV-1.

Abstract: HIV-1 is divided into types and subtypes on the basis of sequence relatedness, and typically only small regions of the viral genome are compared. There are conflicting data on the role played by HIV-1 subtype in HIV-1 disease progression [1, 2]. There is also speculation that HIV-1 subtype is responsible for differences in the epidemic spread of HIV-1. Specifically, subtype C has been associated with what is perceived to be the most rapid epidemic spread of HIV-1. However, it is difficult to discern whether the more rapid spread of subtype C epidemics is due to subtype or to other coexisting factors in populations affected by this subtype. It is possible that sociobehavioral factors preexistent in settings with newly introduced subtype C virus are responsible for the rapid spread of infection within the population, rather than the properties of subtype C virus. It has been challenging to determine the clinical and epidemiologic consequences of genetic differences in HIV-1 subtypes, because many geographic regions have an overwhelming predominance of 1 subtype and insufficient numbers of other subtypes to enable comparisons between them. In some regions that do have >1 frequently circulating HIV-1 subtype, such as Thailand, specific subtypes are associated with specific HIV-1 risk factors (i.e., parenteral versus sexual transmission), which makes it difficult to ascribe transmission differences between subtypes solely to subtype [3]. Perinatal HIV-1 transmission cohorts in sub-Saharan Africa often include women infected with different HIV-1 subtypes. The relative homogeneity of risk behaviors of the mothers in these cohorts may minimize bias and enable comparisons of HIV-1 shedding and transmission between different subtypes. Studies of perinatal transmission have yielded mixed evidence that subtype influences transmission [4, 5]. Mucosal shedding is a frequently used surrogate marker of infectivity. Thus, identification of differences in shedding between HIV-1 subtypes may be an important first step in understanding the role played by HIV-1 subtype in transmission. To determine whether HIV-1 subtype influences shedding in mucosal surfaces or secretions that are responsible for transmission, we compared HIV-1 shedding in genital secretions and breast milk and the risk of mother-to-child transmission of HIV-1 in mothers infected with subtype A, C, or D in Nairobi, Kenya.