The effect of antenatal isoniazid preventive therapy on birth outcomes in Western Kenya.

BACKGROUND: Pregnant women living with HIV (WLHIV) are at high risk for TB. There are limited data to inform whether TB preventive therapy is safe in pregnancy.METHODS: We completed a retrospective study of antenatal and birth records of mother-infant dyads at two health care facilities in Kisumu, Kenya. Among pregnant WLHIV, we assessed the relationship of antenatal isoniazid preventive therapy (IPT) with birth outcomes (preterm birth, low birth weight [LBW], congenital anomalies, and perinatal death).RESULTS: Of 576 mother-infant pairs, most women were on antiretroviral therapy (574, 99.7%) with viral suppression (518, 89.9%) and one-quarter had IPT exposure during pregnancy (152, 26.4%). The prevalence of preterm birth was lower among women with antenatal IPT exposure (21% vs. 30%; P = 0.03). LBW, congenital anomaly and perinatal death were not associated with antenatal IPT; however, we observed a trend toward fewer composite poor birth outcomes among women taking antenatal IPT (26% vs 33%; P = 0.08). Controlling for maternal age and viral load, IPT use during pregnancy was associated with lower odds of preterm birth (aOR 0.62, 95% CI 0.40-0.98; P = 0.04).CONCLUSION: In a programmatic setting in Western Kenya, IPT use was not associated with adverse birth outcomes.

Vaccine safety surveillance in Kenya using GAIA standards: A feasibility assessment of existing national and subnational research and program systems.

BACKGROUND: Active surveillance systems for monitoring vaccine safety among pregnant women address some of the limitations of a current passive surveillance approach utilized in low- and middle-income countries (LMIC). However, few active surveillance systems in LMIC exist. Our study assessed the feasibility of utilizing three existing data collection systems in Kenya for active surveillance of maternal immunization and to assess the applicability of Global Alignment of Immunization Safety Assessment in pregnancy (GAIA) case definitions that were initially developed for clinical trials within these systems. METHODS: We assessed applicability of GAIA case definition for maternal Tetanus Toxoid exposure, stillbirth, low birth weight, small for gestational age, Neonatal Invasive Blood Stream Infection (NIBSI), prematurity and neonatal death in two routine web-based health information systems (Kenya EMR and DHIS-2), and a web-based population-based pregnancy research platform (ANCOV1) in Kenya. RESULTS: All three HIS were capable of reporting selected outcomes to varying degrees of GAIA certainty. The ANCOV platform was the most robust in collecting and collating clinical data for effective maternal pharmacovigilance. The utilization of facility- and district-aggregated data limits the usefulness of DHIS-2 in pharmacovigilance as currently operationalized. While the Kenya EMR contained individual level data and meets the key considerations for effective pharmacovigilance, it was used primarily for HIV care and treatment records in a small proportion of health facilities and would require additional resources to expand to all antenatal care facilities and to link maternal and infant records. DISCUSSION: Population-based research studies may offer a responsive short-term option for implementing maternal vaccine pharmacovigilance in LMICs. However, the foundation exists for long-term capacity building within the national health electronic data systems to provide this critical service as well as ensure participation of the country in international studies on maternal vaccine safety.

Spatial epidemiology of tuberculosis in the high-burden counties of Kisumu and Siaya, Western Kenya, 2012-2015.

BACKGROUND: Effective management of tuberculosis (TB) and reduction of TB incidence relies on knowledge of where, when and to what degree the disease is present. METHODS: In a retrospective cross-sectional study, we analysed the spatial distribution of notified TB incidence from 1 January 2012 and 31 December 2015 in Siaya and Kisumu Counties, Western Kenya. TB data were obtained from the Division of Leprosy, Tuberculosis and Lung Disease, Nairobi, Kenya, as part of an approved TB case detection study. Cases were linked to their corresponding geographic location using physical address identifiers. Spatial analysis techniques were used to examine the spatial and temporal patterns of TB. Assessment of spatial clustering was carried out following Moran's I method of spatial autocorrelation and the Getis-Ord Gi* statistic. RESULTS: The notified TB incidence varied from 638.0 to 121.4 per 100 000 at the small area level. Spatial analysis identified 16 distinct geographic regions with high TB incidence clustering (GiZScore 2.58, P < 0.01). There was a positive correlation between population density and TB incidence that was statistically significant (rs = 0.5739, P = 0.0001). CONCLUSION: The present study presents an opportunity for targeted interventions in the identified subepidemics to supplement measures aimed at the general population.

The FEN1 E359K germline mutation disrupts the FEN1-WRN interaction and FEN1 GEN activity, causing aneuploidy-associated cancers.

Polymorphisms and somatic mutations in Flap Endonuclease 1 (FEN1), an essential enzyme involved in DNA replication and repair, can lead to functional deficiencies of the FEN1 protein and a predisposition to cancer. We identified a FEN1 germline mutation that changed residue E359 to K in a patient whose family had a history of breast cancer. We determined that the E359K mutation, which is in the protein-protein domain of FEN1, abolished the interaction of FEN1 with Werner syndrome protein (WRN), an interaction that is critical for resolving stalled DNA replication forks. Furthermore, although the flap endonuclease activity of FEN1 E359K was unaffected, it failed to resolve bubble structures, which require the FEN1 gap-dependent endonuclease activity. To determine the etiological significance of E359K, we established a mouse model containing this mutation. E359K mouse embryonic fibroblasts (MEF) were more sensitive to DNA crosslinking agents that cause replication forks to stall. Cytological analysis suggested that the FEN1-WRN interaction was also required for telomere stability; mutant cell lines had fragile telomeres, increased numbers of spontaneous chromosomal anomalies and higher frequencies of transformation. Moreover, the incidence of cancer was significantly higher in mice homozygous for FEN1 E359K than in wild-type mice, suggesting that the FEN1 E359K mutation is oncogenic.

Morphological evaluation of spermatogenesis in Lake Magadi tilapia (Alcolapia grahami): a fish living on the edge.

Spermatogenesis in Lake Magadi tilapia (Alcolapia grahami), a cichlid fish endemic to the highly alkaline and saline Lake Magadi in Kenya, was evaluated using light and transmission electron microscopy. Spermatogenesis, typified by its three major phases (spermatocytogenesis, meiosis and spermiogenesis), was demonstrated by the presence of maturational spermatogenic cells namely spermatogonia, spermatocytes, spermatids and spermatozoa. Primary spermatogonia, the largest of all the germ cells, underwent a series of mitotic divisions producing primary spermatocytes, which then entered two consecutive meiotic divisions to produce secondary spermatocytes and spermatids. Spermatids, in turn, passed through three structurally distinct developmental stages typical of type-I spermiogenesis to yield typical primitive anacrosomal spermatozoa of the externally fertilizing type (aquasperm). The spermatozoon of this fish exhibited a spheroidal head with the nucleus containing highly electron-dense chromatin globules, a midpiece containing ten ovoid mitochondria arranged in two rows and a flagellum formed by the typical 9 + 2 microtubule axoneme. In addition, the midpiece, with no cytoplasmic sheath, appeared to end blindly distally in a lobe-like pattern around the flagellum; a feature that was unique and considered adaptive for the spermatozoon of this species to the harsh external environment. These observations show that the testis of A. grahami often undergoes active spermatogenesis despite the harsh environmental conditions to which it is exposed on a daily basis within the lake. Further, the spermiogenic features and spermatozoal ultrastructure appear to be characteristic of Cichlidae and, therefore, may be of phylogenetic significance.

Khat (Catha edulis) lowers plasma luteinizing hormone (LH) and testosterone secretion, but increases cortisol levels in male rabbits.

AIM: This study investigated the effects of fresh khat extract on specific circulating hormones in male rabbits. MATERIALS AND METHODS: A total of 25 male New Zealand White rabbits were divided into five groups each comprising five animals. The first four groups were fed four doses (1.5 g/kg, 4.5 g/kg, 13.5 g/kg and 40.5 g/kg body weight) of khat extract twice a week for 5 weeks while the last group, serving as control, was fed only normal saline via intragastric tube. Blood samples were collected at 15 min interval for up to 3 h after khat extract administration and plasma assayed for luteinizing hormone (LH), testosterone and cortisol levels using radioimmunoassay technique. RESULTS: Khat extract at all doses significantly lowered (P<0.05) LH pulse frequency, area under LH curve, mean plasma LH and mean plasma testosterone levels. Plasma cortisol levels were significantly elevated (P<0.05) in khat-treated rabbits in a dose-dependent manner. CONCLUSION: This study demonstrates that khat may impair reproductive function in male rabbits by interfering with sex hormone profiles.

Multidrug Resistance of Salmonella Enterica Serovars Typhi and Als in Western Kenya

Background: The threat to human health posed by antibiotic resistance is of growing concern. Many commensals and pathogenic organisms have developed resistance to well established and newer antibiotics. This is a cross-sectional study within two hospital settings to determine in vitro antibiotic susceptibilities of Salmonella species isolated in blood; cerebral spinal fluid; pus and stool collected from in- and out-patients. The inclusion criteria was non restrictive to in- and out-patient but preference to severe diarrhea cases with negligible changes to previous treatment regimen was observed. The study was carried out from February 2004 - June 2005. Fifty-three diarrhea patients within the hospital who were chosen by convenient sampling and consented to participate in the study were considered. Methodology: Either blood or pus was collected using vacutainer tubes and syringe; swabs respectively; and cerebral spinal fluid by lumbar puncture from patients who had fever (temp = 38oC) and diarrhea. Stool samples were also colle cted and all specimens analyzed for the presence of Salmonella by routine microbiological procedures. The isolates were subjected to antibiotic susceptibility testing using disc diffusion technique. Results: In St. Elizabeth Mukumu Mission Hospital; Salmonella enterica serovar Typhi was most common (56.6; n=33); followed by S. typhimurium (34; n=18); while in Maseno Mission Hospital only S. typhimurium was isolated. Whereas S. typhi was more commonly isolated in male adults and female children (P = 0.9); S. typhimurium was more common in female and male children (P=0.1). All the isolates were sensitive to ciprofloxacin. However; S. typhi was resistant to streptomycin; ampicillin; chloramphenical and cotrimoxazole; S. typhimurium to tetracycline; sulfamethoxazole; cotrimoxazole; ampicillin; chloramphenical and streptomycin. Conclusions: S. typhi displayed a high resistance pattern to most antibiotic screened than S. typhimurium

Antileukemic and cytogenetic activity by triple administration of three modified steroidal derivatives of nitrogen mustards.

Combination chemotherapy is widely and routinely used for most cancer patients. The main objective of this study is an effort to develop new anticancer drugs and procedures with enhanced antitumor activity and reduced toxicity. This study was designed to determine the antileukemic and cytogenetic activity of five mixtures of three specific steroidal esters of aromatic nitrogen mustards in different proportions. This is the next step of two previous studies where the combination of two such esteric analogues was investigated with promising results. All of the five mixtures used proved active against leukemia P388 and in the induction of sister chromatid exchanges, indicating that the combination of the same class of compounds can be successful, especially when a highly potent agent is combined with another less active but probably mechanistically supplementary one. These results can be used in future experiments in order to further scout the specific role of the steroidal part of these molecules in the antileukemic potency of them.

Early testicular response to intraperitoneal administration of ethane dimethanesulphonate (EDS) in the goat (Capra hircus).

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.

Epididymal epithelial cell involution following a single intraperitoneal administration of ethane dimethanesulfonate in the goat (Capra hircus).

Ethane dimethanesulfonate (EDS) selectively destroys Leydig cells in rats and a few other smaller animal species but not in mice and quail. In the teleost fish, it stimulates testicular activity instead. It also causes formation of sperm granulomas, reduction of sperm fertilizing ability, and destruction of clear cells in the epididymis. Investigations involving larger animal species are scanty. We have previously reported that EDS has no effect on goat Leydig cells but appears to have a direct cytotoxic effect on the seminiferous epithelium. This study was therefore designed to investigate the effects of EDS on goat epididymal cytoarchitecture. EDS was administered intraperitoneally at two dose levels, 75 and 25 mg/kg body wt. The former dose was rather toxic, killing three of five goats in this group within 24 h whereas the latter dose was well tolerated. Six days after treatment, the goats were hemicastrated and the epididymis was isolated and processed for light and electron microscopy. Involution associated with EDS was observed in epithelial cells of all regions of the epididymis, each having its own specific and peculiar changes. In the caput, there was increased cytoplasmic density accompanied by enlarged vacuoles and paucity of secretory vesicles in the apical cytoplasm. The Golgi cisternae were dilated and disorganized and, in the basal aspect, large dense staining bodies or inclusions, degenerative mitochondria, and lamellated bodies were observed. In the corpus, large vacuoles containing flocculent materials occurred in the entire cell cytoplasm but were particularly numerous and large in the midcytoplasm, completely obliterating the Golgi area. There was a dramatic reduction in epithelial height in the cauda epididymis accompanied by sparse distribution of markedly shortened microvilli. The epithelial cells had extensively lobulated nuclei and disorganized cytoplasm with dilated Golgi apparatus and large conglomerations of tubular structures. These structural changes suggest that EDS causes degeneration of goat epididymal epithelial cells. These effects are likely to result from the direct action of the compound on the epithelium.

Morphological characterization of the seminiferous cycle in the goat (Capra hircus): a histological and ultrastructural study.

The cycle of spermatogenesis/seminiferous cycle was investigated in the goat testis using both light and electron microscopy techniques. Using the various cell associations and the accompanying changes in spermatid shape and location, the cycle was divided into eight (8) successive stages. The cycle began with the accomplishment of spermiation (stage 1) and ended with apical migration and close attachment of late maturation phase spermatids at the Sertoli cell apex accompanied by adluminal retention of residual bodies with dense staining inclusions (stage 8). The early stages of the cycle (stages 1-4) were therefore characterized by the presence of only one generation of spermatids, the second one appearing only after the division of secondary spermatocytes in stage 4. Consequently, stages 5-8 had two generations of spermatids; Golgi or cap phase as well as maturation phase spermatids. Although stages 5 to 7 appeared as distinct entities, stages 6 and 7 were rather short-lived and considered as continuations of stage 5. Therefore, the 8 stages of the cycle in the goat were further condensed into 6 main divisions. The duration of each stage was estimated by the frequency of occurrence in sections. Among these, stage 1 had the highest frequency (34%) followed by stages 5-7 (27%). Stages 8 and 4 had the shortest frequency (up to 9%) while stages 2 and 3 had 13% and 12% respectively. These results indicate that, like most domestic species, goats have a cycle of 8 stages with 6 main divisions, the longest being stage 1.

In vitro production of testosterone and plasma levels of luteinising hormone, testosterone and cortisol in male rats treated with heptachlor.

Male rats were divided into six groups of five rats each. Rats were injected subcutaneously with different concentrations of heptachlor for 2 weeks. Heptachlor at all doses significantly suppressed plasma testosterone levels (P < 0.05). Plasma luteinizing hormone (LH) (P < 0.01) and cortisol (P < 0.02) levels were significantly elevated in heptachlor-treated rats as compared to corn oil-treated controls. LH and testosterone levels showed strong correlation (r = 0.69, P < 0.05). The testes in rats treated with 25 mg/kg body weight of heptachlor showed some pathological changes. We conclude that heptachlor causes adverse effects on several male reproductive parameters in rats.

Ultrastructural study of the testis of non-breeding naked mole-rat (Heterocephalus glaber, Ruppell).

The testicular structure of the wild caught naked mole rat was studied. It comprises of a large volume of lipid-rich interstitial cells of Leydig among which are few scattered seminiferous tubules. In addition, the interstitial cells possess elongated mitochondria and vast network of smooth endoplasmic reticulum (sER). The Golgi apparatus (GA) apparently is not conspicuous or well developed. All stages of spermatogenesis occur in the seminiferous tubules although the mature forms (secondary spermatocytes, spermatids and spermatozoa) are few. Sertoli cells show an irregular nucleus, mitochondria oriented perpendicular to the basement membrane, a vast network of endoplasmic reticulum with sER as the predominant form and lipid droplets. The ultrastructural features of Leydig cells seem to suggest a steroidogenic capacity although the vast accumulation of lipid droplets may imply impaired utilisation of cholesterol reservoir as a result of pituitary hormonal imbalance or (and) the local paracrine influence by Sertoli cells. The cause of slow-down in spermatogenesis is still unclear but may also be under the influence of pheromonal cues or the local paracrine control. Sertoli cell features point towards a role of synthesis and secretion.