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2.
Vet Parasitol Reg Stud Reports ; 38: 100829, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36725161

RESUMEN

INTRODUCTION: Cystic Echinococcosis (CE) is endemic in humans and livestock in many pastoral communities in Kenya. The distribution of the disease is enhanced by several factors, including livestock trade, which has allowed for the spread of CE to non-endemic areas such as western Kenya. Dogs' roaming behaviour, with consequent contamination of the environment with intestinal parasites, could then lead to parasite establishment. This study examined dogs' infection levels with taeniid eggs and their potential role in contaminating the environment with intestinal parasites. METHODOLOGY: We selected sixteen ruminant slaughterhouses in Busia and Bungoma Counties, and around each slaughterhouse we identified ten homesteads owning free-roaming dogs. We administered a questionnaire on dog management practices to the homestead owner and collected a faecal sample from the dog's rectum. In homesteads around 8 of the 16 slaughterhouses, we collared dogs with a GPS tracker to assess their movement patterns. The faecal samples were examined microscopically following zinc-chloride sieving-floatation technique for the presence of taeniid eggs and other canine intestinal parasites. Polymerase Chain Reaction - Restriction Fragment Length Polymorphism of NADH dehydrogenase subunit 1 gene and sequencing were used to confirm taeniid eggs identified during microscopy. Additionally, the Coproantigen-ELISA was used to detect the presence of taeniid antigen in a sub-set of the faecal samples. RESULTS: Helminths detected in the 155 dogs sampled included hookworms (n = 92; 59.4%), ascarids (n = 15; 9.7%), and taeniids (n = 1; 0.6%). Through Copro-PCR, 13 eggs extracted from the sample of the only taeniid infected dog were sequenced and identified as E. canadensis (G6/7) [n = 1], Taenia multiceps [n = 1], and Taenia serialis [n = 6]; the remaining were indeterminate. Of the 77 faecal samples tested for E. granulosus sensu lato (s. l.) with the Copro-ELISA, 64 (83.1%) were negative, 12 (15.6%) were positive, while 1 (1.3%) was suspicious. The dogs travelled a median of 13.5 km daily, and 28 dogs visited the slaughterhouses during the 5-day recording period. CONCLUSION: The results indicate a relatively high carriage of zoonotic parasites by free-roaming domestic dogs in western Kenya, which poses a risk to human and livestock populations. We report for the first time a domestic lifecycle of Echinococcus canadensis and Taenia multiceps in western Kenya, as well as a presumptive sylvatic cycle of coenurosis by T. serialis. We recommend an extensive and ongoing Copro-antigen survey of dog faeces, broader assessment of dog parasites with zoonotic potential, adherence to slaughterhouse management practices, and dog-ownership programmes to highlight the importance of deworming and restricted dog movements.


Asunto(s)
Equinococosis , Echinococcus , Parasitosis Intestinales , Taenia , Animales , Perros , Equinococosis/veterinaria , Echinococcus/genética , Parasitosis Intestinales/veterinaria , Kenia/epidemiología , Estadios del Ciclo de Vida , Taenia/genética
4.
Nat Biotechnol ; 40(1): 20-21, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34997245
5.
PLOS Glob Public Health ; 2(8): e0000235, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36962714

RESUMEN

Cystic Echinococcosis (CE) is a zoonosis caused by infection with the larval stages of the taeniid cestodes of the species complex Echinococcus granulosus sensu lato. It is prevalent among transhumant communities in East Africa, including those residing in northern Kenya. The movement of livestock from these regions of high incidence to areas of low incidence creates an indirect risk of disease spill-over to humans. To assess possible establishment of the CE life cycle outside known endemic regions, we used a portable ultrasound scanner to screen for the presence of human CE in Bungoma County of western Kenya, an area which imports substantial numbers of cattle for slaughter from neighbouring pastoralist regions. Eight sentinel sites were purposively selected based on their proximity to slaughterhouses handling animals introduced from pastoralist regions, and necessary permissions to conduct the study were sought. Regression analyses were conducted to identify risk factors associated with the presence of abdominal and cystic lesions (CL). In total, 1002 participants were screened; of these, 654 (65.3%) were female and the median age was 43. Farming (n = 403; 43.4%) was the most frequent occupation, followed by professional (i.e. on regular salary) (n = 215; 23.1%), and business (n = 207; 22.3%) categories. Sixty-seven participants (6.7%) had abnormal ultrasound findings, of these, 7 (1.1%) had simple liver cysts/CL, as per WHO classification. As such, their outcome was inconclusive and they were not put on treatment but advised to attend follow-up investigations in a referral health facility. Other abnormal findings included splenomegaly (n = 14), ovarian cysts (n = 14), uterine fibroids (n = 10), polycystic kidneys (n = 6), and benign prostatic hyperplasia (n = 6). Age was unconditionally associated with the presence of presumptive CL. These results contribute to CE baseline data while providing insights on the implementation of ultrasound diagnosis in the field, as recommended by the WHO for targeted control of echinococcosis by 2030.

6.
BMC Res Notes ; 12(1): 422, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31311578

RESUMEN

OBJECTIVES: Plasmids harbour antibiotic resistance genes which contribute to the emergence of multidrug resistant pathogens. We detected the presence of plasmids in multidrug resistant Salmonella enterica serovar Typhi (S. Typhi) isolates from our previous study and consequently determined their incompatibility groups and possibility of conjugation transmission. Plasmids were extracted from 98 multidrug resistant S. Typhi isolates based on alkaline lysis technique. Plasmid incompatibility grouping was established by PCR replicon typing using 18 pairs of primers to amplify FIA, FIB, FIC, HI1, HI2, I1-Iγ, L/M, N, P, W, T, A/C, K, B/O, X, Y, F and FIIA replicons. Antibiotic resistance phenotypes were conjugally transferred from S. Typhi isolates with plasmids to Escherichia coli K12F strain devoid of plasmids. RESULTS: Approximately 79.6% of the MDR S. Typhi isolates were related to the existence of plasmids. We detected 93.6% of plasmids belonging to incompatibility (Inc) group HI1. The other incompatibility groups identified included IncFIC (16.7%), IncP (1.3%), and IncI1 (1.3%) which appeared together with Inc HI1. MDR S. Typhi isolated carried a homologous plasmid of incompatibility group HI1 most of which transferred the resistance phenotypes of ampicillin, tetracycline and chloramphenicol to the transconjugants.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Plásmidos/genética , Salmonella typhi/efectos de los fármacos , Ampicilina/farmacología , Cloranfenicol/farmacología , Conjugación Genética/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Humanos , Kenia , Pruebas de Sensibilidad Microbiana , Replicón/genética , Salmonella typhi/clasificación , Salmonella typhi/genética , Tetraciclina/farmacología , Fiebre Tifoidea/microbiología
7.
BMC Microbiol ; 18(1): 187, 2018 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-30428828

RESUMEN

BACKGROUND: Typhoid fever remains a public health concern in developing countries especially among the poor who live in informal settlements devoid of proper sanitation and clean water supply. In addition antimicrobial resistance poses a major challenge in management of the disease. This study assessed the antimicrobial susceptibility patterns of Salmonella enterica serotype Typhi (S. Typhi) isolated from typhoid fever cases (2004-2007). METHODS: A cross sectional study was conducted on 144 archived S. Typhi isolates (2004-2007) tested against 11 antimicrobial agents by quality controlled disk diffusion technique. Isolates resistant to ampicillin, chloramphenicol, and cotrimoxazole were considered Multidrug resistant (MDR). Thirty MDR isolates were selected randomly and further tested using minimum inhibitory concentration (MIC) E-test. RESULTS: Sixteen percent (23/144) of the isolates were susceptible to all the antibiotics tested while 68% were resistant to three or more of the 11 antibiotics tested. The isolates showed a high susceptibility to ceftriaxone (94%) and gentamicin (97%). A high percentage of resistance was observed for the conventional first-line antibiotics; ampicillin (72%), chloramphenicol (72%), and cotrimoxazole (70%). Sixty-nine percent of the isolates (100/144) showed reduced susceptibility to ciprofloxacin. All the 30 (100%) isolates selected for MIC test were susceptible to amoxicillin-clavulanic acid. All except one of the 30 isolates were susceptible to ceftriaxone while majority 21 (70%) recorded an intermediate susceptibility to ciprofloxacin with MIC of 0.12-0.5 µg/mL. CONCLUSION: A large proportion of S. Typhi isolates were MDR and also showed reduced susceptibility to ciprofloxacin. Fluoroquinolone resistance is emerging and this may pose a challenge in treatment of typhoid in future. There is need for routine surveillance to monitor this phenotype in clinical settings.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Salmonella typhi/efectos de los fármacos , Salmonella typhi/aislamiento & purificación , Fiebre Tifoidea/microbiología , Ampicilina/farmacología , Ceftriaxona/farmacología , Cloranfenicol/farmacología , Ciprofloxacina/farmacología , Estudios Transversales , Fluoroquinolonas/farmacología , Humanos , Kenia , Pruebas de Sensibilidad Microbiana , Salmonella typhi/clasificación , Salmonella typhi/genética , Combinación Trimetoprim y Sulfametoxazol/farmacología
8.
Mol Biol Rep ; 45(6): 1849-1862, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30168097

RESUMEN

The stearoyl-CoA desaturase 1 (SCD1) A293V and acyl CoA: diacylglycerol acyltransferase 1 (DGAT1) K232A polymorphisms have been associated with significant variation in bovine milk fatty acid composition and unsaturation indices in western cattle breeds. This study aimed to estimate the milk fatty acid variability in indigenous Borgou and White Fulani cattle breeds of Benin, and the effects of the SCD1 A293V and DGAT1 K232A polymorphisms on milk and fatty acid composition and unsaturation indices. Thus, 85 Borgou and 96 White Fulani cows were genotyped for the SCD1 A293V and DGAT1 K232A polymorphisms and their milk and fatty acid composition and unsaturation indices were determined. Borgou presented milk with higher linoleic acid (P < 0.001), oleic acid (P < 0.05), C18 index (P < 0.001), total unsaturation index (P < 0.05), and lower total saturated fatty acid (SFA) compared to White Fulani. The SCD1 VV genotype was associated with higher protein and lactose contents in White Fulani (P < 0.05). In Borgou, the SCD1 AV genotype was associated with higher C14 and total unsaturation indices (P < 0.01), while the SCD1 V allele was associated with decrease in C14 index (P < 0.05). In White Fulani, the SCD1 VV genotype was associated with lower C18:1 cis-9 content (P < 0.05) while the DGAT1 K allele was associated with increased total SFA (P < 0.05), and decreased C18 index (P < 0.05), total unsaturation index (P < 0.01) and total monounsaturated fatty acid (P < 0.01). The SCD1 A293V and DGAT1 K232A may serve as genetic markers to improve milk fatty acid traits in Borgou and White Fulani breeds.


Asunto(s)
Diacilglicerol O-Acetiltransferasa/genética , Estearoil-CoA Desaturasa/genética , Alelos , Animales , Cruzamiento/métodos , Bovinos/genética , Ácidos Grasos/genética , Femenino , Frecuencia de los Genes/genética , Marcadores Genéticos , Variación Genética/genética , Genotipo , Leche/metabolismo , Fenotipo , Polimorfismo Genético/genética
9.
Trop Anim Health Prod ; 50(8): 1871-1879, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29915876

RESUMEN

Livestock traders are a key conduit for incentives in livestock production systems. Their actions affect producer prices, investment decisions, and their livelihoods. However, smallholder farmers in rural communities of eastern Africa often have limited understanding of the marketing process and the interactions among market actors. This study was undertaken following the introduction of improved indigenous goat and sheep breeds in Climate Smart Villages of Nyando in western Kenya. We sought to understand the marketing of sheep and goats in five key rural markets used by the smallholder farmers of Nyando, to generate information on key market actors, their functions in the value chain, and their preferences for attributes in sheep and goats. Most traders (65%) in all the markets were men. Four different types of traders operated in the markets, producers, retailers, wholesalers, and brokers, each making a profit. Preference for selling sheep or goats and the animal attributes desired by the traders differed depending on the surrounding community. Markets in Kericho County of Nyando traded more goats than sheep while those in Kisumu County of Nyando traded more sheep than goats. There were no clear policies guiding pricing of animals. Prices offered to producers depended on previous days, and the number of animals available for sale at the marketing point. The collaborative group actions of the producers in the Climate Smart Villages did not extend beyond the level of production to the marketing of their livestock. A critical change is required for the smallholder farmers to derive better incomes from improved quality of animals following adoption of improved breeding and management practices. The results illustrate the need to engage rural market actors when implementing livestock improvement programs for smallholder farmers for better farm gate prices of animals, and thus achieve the improved incomes envisioned.


Asunto(s)
Cabras , Ganado , Mercadotecnía , Población Rural , Ovinos , Adulto , Animales , Bovinos , Clima , Comercio , Costos y Análisis de Costo , Ambiente , Agricultores , Granjas , Femenino , Humanos , Kenia , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Virol J ; 14(1): 29, 2017 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-28196510

RESUMEN

BACKGROUND: HIV-1 is highly variable genetically and at protein level, a property it uses to subvert antiviral immunity and treatment. The aim of this study was to assess if HIV subtype differences were associated with variations in glycosylation patterns and co-receptor tropism among HAART patients experiencing different virologic treatment outcomes. METHODS: A total of 118 HIV env C2V3 sequence isolates generated previously from 59 Kenyan patients receiving highly active antiretroviral therapy (HAART) were examined for tropism and glycosylation patterns. For analysis of Potential N-linked glycosylation sites (PNGs), amino acid sequences generated by the NCBI's Translate tool were applied to the HIVAlign and the N-glycosite tool within the Los Alamos Database. Viral tropism was assessed using Geno2Pheno (G2P), WebPSSM and Phenoseq platforms as well as using Raymond's and Esbjörnsson's rules. Chi square test was used to determine independent variables association and ANOVA applied on scale variables. RESULTS: At respective False Positive Rate (FPR) cut-offs of 5% (p = 0.045), 10% (p = 0.016) and 20% (p = 0.005) for CXCR4 usage within the Geno2Pheno platform, HIV-1 subtype and viral tropism were significantly associated in a chi square test. Raymond's rule (p = 0.024) and WebPSSM (p = 0.05), but not Phenoseq or Esbjörnsson showed significant associations between subtype and tropism. Relative to other platforms used, Raymond's and Esbjörnsson's rules showed higher proportions of X4 variants, while WebPSSM resulted in lower proportions of X4 variants across subtypes. The mean glycosylation density differed significantly between subtypes at positions, N277 (p = 0.034), N296 (p = 0.036), N302 (p = 0.034) and N366 (p = 0.004), with HIV-1D most heavily glycosylated of the subtypes. R5 isolates had fewer PNGs than X4 isolates, but these differences were not significant except at position N262 (p = 0.040). Cell-associated isolates from virologic treatment success subjects were more glycosylated than cell-free isolates from virologic treatment failures both for the NXT (p = 0.016), and for all the patterns (p = 0.011). CONCLUSION: These data reveal significant associations of HIV-1 subtype diversity, viral co-receptor tropism, viral suppression and envelope glycosylation. These associations have important implications for designing therapy and vaccines against HIV. Heavy glycosylation and preference for CXCR4 usage of HIV-1D may explain rapid disease progression in patients infected with these strains.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/fisiología , Tropismo Viral , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen env del Virus de la Inmunodeficiencia Humana/metabolismo , Biología Computacional , Variación Genética , Glicosilación , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Kenia , Análisis de Secuencia
11.
PLoS One ; 12(2): e0172960, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28235021

RESUMEN

Treatment failure is a key challenge in the management of HIV-1 infection. We conducted a mixed-model survey of plasma nevirapine (NVP) concentrations (cNVP) and viral load in order to examine associations with treatment and adherence outcomes among Kenyan patients on prolonged antiretroviral therapy (ART). Blood plasma was collected at 1, 4 and 24 hours post-ART dosing from 58 subjects receiving NVP-containing ART and used to determine cNVP and viral load (VL). Median duration of treatment was 42 (range, 12-156) months, and 25 (43.1%) of the patients had virologic failure (VF). cNVP was significantly lower for VF than non- VF at 1hr (mean, 2,111ng/ml vs. 3,432ng/ml, p = 0.003) and at 4hr (mean 1,625ng/ml vs. 3,999ng/ml, p = 0.001) but not at 24hr post-ART dosing. Up to 53.4%, 24.1% and 22.4% of the subjects had good, fair and poor adherence respectively. cNVP levels peaked and were > = 3µg.ml at 4 hours in a majority of patients with good adherence and those without VF. Using a threshold of 3µg/ml for optimal therapeutic nevirapine level, 74% (43/58), 65.5% (38/58) and 86% (50/58) of all patients had sub-therapeutic cNVP at 1, 4 and 24 hours respectively. cNVP at 4 hours was associated with adherence (p = 0.05) and virologic VF (p = 0.002) in a chi-square test. These mean cNVP levels differed significantly in non-parametric tests between adherence categories at 1hr (p = 0.005) and 4hrs (p = 0.01) and between ART regimen categories at 1hr (p = 0.004) and 4hrs (p<0.0001). Moreover, cNVP levels correlated inversely with VL (p< = 0.006) and positively with adherence behavior. In multivariate tests, increased early peak NVP (cNVP4) was independently predictive of lower VL (p = 0.002), while delayed high NVP peak (cNVP24) was consistent with increased VL (p = 0.033). These data strongly assert the need to integrate plasma concentrations of NVP and that of other ART drugs into routine ART management of HIV-1 patients.


Asunto(s)
Fármacos Anti-VIH/sangre , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Nevirapina/sangre , Adolescente , Adulto , Anciano , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/uso terapéutico , Niño , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/virología , Humanos , Kenia , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Nevirapina/farmacocinética , Nevirapina/uso terapéutico , Insuficiencia del Tratamiento , Carga Viral , Adulto Joven
12.
F1000Res ; 5: 1949, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27703667

RESUMEN

Mosquitoes are a diverse group of invertebrates, with members that are among the most important vectors of diseases. The correct identification of mosquitoes is paramount to the control of the diseases that they transmit. However, morphological techniques depend on the quality of the specimen and often unavailable taxonomic expertise, which may still not be able to distinguish mosquitoes among species complexes (sibling and cryptic species). High resolution melting (HRM) analyses, a closed-tube, post-polymerase chain reaction (PCR) method used to identify variations in nucleic acid sequences, has been used to differentiate species within the Anopheles gambiae and Culex pipiens complexes. We validated the use of PCR-HRM analyses to differentiate species within Anopheles and within each of six genera of culicine mosquitoes, comparing primers targeting cytochrome b ( cyt b), NADH dehydrogenase subunit 1 (ND1), intergenic spacer region (IGS) and cytochrome c oxidase subunit 1 ( COI) gene regions. HRM analyses of amplicons from all the six primer pairs successfully differentiated two or more mosquito species within one or more genera ( Aedes ( Ae. vittatus from Ae. metallicus), Culex ( Cx. tenagius from Cx. antennatus, Cx. neavei from Cx. duttoni, cryptic Cx. pipiens species), Anopheles ( An. gambiae s.s. from An. arabiensis) and Mansonia ( Ma. africana from Ma. uniformis)) based on their HRM profiles. However, PCR-HRM could not distinguish between species within Aedeomyia ( Ad. africana and Ad. furfurea), Mimomyia ( Mi. hispida and Mi. splendens) and Coquillettidia ( Cq. aurites, Cq. chrysosoma, Cq. fuscopennata, Cq. metallica, Cq. microannulatus, Cq. pseudoconopas and Cq. versicolor) genera using any of the primers. The IGS and COI barcode region primers gave the best and most definitive separation of mosquito species among anopheline and culicine mosquito genera, respectively, while the other markers may serve to confirm identifications of closely related sub-species. This approach can be employed for rapid identification of mosquitoes.

13.
J Med Entomol ; 53(6): 1348-1363, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27402888

RESUMEN

The Lake Baringo and Lake Victoria regions of Kenya are associated with high seroprevalence of mosquito-transmitted arboviruses. However, molecular identification of potential mosquito vector species, including morphologically identified ones, remains scarce. To estimate the diversity, abundance, and distribution of mosquito vectors on the mainland shores and adjacent inhabited islands in these regions, we collected and morphologically identified adult and immature mosquitoes and obtained the corresponding sequence variation at cytochrome c oxidase 1 (COI) and internal transcribed spacer region 2 (ITS2) gene regions. A total of 63 species (including five subspecies) were collected from both study areas, 47 of which have previously been implicated as disease vectors. Fourteen species were found only on island sites, which are rarely included in mosquito diversity surveys. We collected more mosquitoes, yet with lower species composition, at Lake Baringo (40,229 mosquitoes, 32 species) than at Lake Victoria (22,393 mosquitoes, 54 species). Phylogenetic analysis of COI gene sequences revealed Culex perexiguus and Cx tenagius that could not be distinguished morphologically. Most Culex species clustered into a heterogeneous clade with closely related sequences, while Culex pipiens clustered into two distinct COI and ITS2 clades. These data suggest limitations in current morphological identification keys. This is the first DNA barcode report of Kenyan mosquitoes. To improve mosquito species identification, morphological identifications should be supported by their molecular data, while diversity surveys should target both adults and immatures. The diversity of native mosquito disease vectors identified in this study impacts disease transmission risks to humans and livestock.


Asunto(s)
Distribución Animal , Culicidae/fisiología , Variación Genética , Mosquitos Vectores/fisiología , Animales , Biota , Culicidae/anatomía & histología , Culicidae/genética , Culicidae/crecimiento & desarrollo , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Femenino , Proteínas de Insectos/genética , Islas , Kenia , Lagos , Larva/anatomía & histología , Larva/genética , Larva/crecimiento & desarrollo , Larva/fisiología , Masculino , Mosquitos Vectores/anatomía & histología , Mosquitos Vectores/genética , Mosquitos Vectores/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Óvulo/fisiología , Filogenia , Densidad de Población , Pupa/anatomía & histología , Pupa/genética , Pupa/crecimiento & desarrollo , Pupa/fisiología , Análisis de Secuencia de ADN
14.
Anim Genet ; 47(3): 377-81, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26765790

RESUMEN

The history of domestic sheep (Ovis aries) in Africa remains largely unknown. After being first introduced from the Near East, sheep gradually spread through the African continent with pastoral societies. The eastern part of Africa was important either for the first diffusion of sheep southward or for putative secondary introductions from the Arabian Peninsula or southern Asia. We analysed mitochondrial DNA control region sequences of 91 domestic sheep from Kenya and found a high diversity of matrilines from the widespread haplogroup B, whereas only a single individual from haplogroup A was detected. Our phylogeography analyses of more than 500 available mitochondrial DNA sequences also identified ancestral haplotypes that were probably first introduced in Africa and are now widely distributed. Moreover, we found no evidence of an admixture between East and West African sheep. The presence of shared haplotypes in eastern and ancient southern African sheep suggests the possible southward movement of sheep along the eastern part of Africa. Finally, we found no evidence of an extensive introduction of sheep from southern Asia into Africa via the Indian Ocean trade. The overall findings on the phylogeography of East African domestic sheep set the grounds for understanding the origin and subsequent movements of sheep in Africa. The richness of maternal lineages in Kenyan breeds is of prime importance for future conservation and breeding programmes.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Oveja Doméstica/genética , Animales , Cruzamiento , Genética de Población , Haplotipos , Kenia , Filogeografía , Análisis de Secuencia de ADN
15.
Glob Ecol Conserv ; 8: 31-40, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28203619

RESUMEN

Rural communities value Faidherbia albida in farming systems and pastoralism. Faidherbia albida provides products such as medicine, fodder, fuel, wood, food and services such as shade, soil fertility and nutrient cycling. Excessive browsing by animals, branch lopping and pod harvesting, have critically reduced the natural regeneration in some areas which exposes it to challenges due to dependence upon natural regeneration. The objective of this research was to evaluate response of Faidherbia albida provenances from eastern (Taveta Wangingombe) and southern Africa (Lupaso, Kuiseb Manapools) to different watering regimes to aid in selection of provenances for domestication. The observed difference in growth was analyzed to determine whether they are genetic or environmentally induced. Genotype  [Formula: see text]  interaction were significant at ([Formula: see text]0.001, p[Formula: see text]0.05) in seedling height, diameter and leaf numbers. Seedling height (r=0.94 p=0.001) recorded the highest correlation coefficient among all the growth variables analyzed. The growth variation was greater for seedling height than that of diameter and leaf numbers (h[Formula: see text]=0.97). Hierarchical cluster analysis grouped the provenances into three clusters with cluster iii consisting of Taveta, Kuiseb and Lupaso while cluster ii and i composed of Wangingombe and Manapools respectively. Manapools recorded the highest genetic distance from Taveta, Kuiseb and Lupaso at 84.55 units. Wangingombe and Manapools are closely related genetically at a distance of 7.32. The maximum inter-cluster distance between cluster i and iii indicated wider genetic diversity between the provenances in these clusters and selection should be from this clusters for hybridization program to achieve novel breeds.

16.
Afr J Lab Med ; 3(1): 41, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-29043171

RESUMEN

BACKGROUND: Since 1971, Kenya has had repeated cholera outbreaks. However, the cause of seasonal epidemics of cholera is not fully understood and neither are the factors that drive epidemics, both in Kenya and globally. OBJECTIVES: The objectives of the study were to determine the environmental reservoirs of V. cholerae during an interepidemic period in Kenya and to characterise their virulence factors. METHODS: One hundred (50 clinical, 50 environmental) samples were tested for V. cholerae isolates using both simplex and multiplex polymerase chain reaction. RESULTS: Both sediments and algae from fishing and landing bays yielded isolates of V. cholerae. Clinical strains were characterised along with the environmental strains for comparison. All clinical strains harboured ctxA, tcpA (El Tor), ompU, zot, ace, toxR, hylA (El Tor) and tcpI genes. Prevalence for virulence genes in environmental strains was hylA (El Tor) (10%), toxR (24%), zot (22%), ctxA (12%), tcpI (8%), hylA (26%) and tcpA (12%). CONCLUSION: The study sites, including landing bays and beaches, contained environmental V. cholerae, suggesting that these may be reservoirs for frequent epidemics. Improved hygiene and fish-handling techniques will be important in reducing the persistence of reservoirs.

17.
J Virol Methods ; 193(1): 23-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23692685

RESUMEN

Yellow fever, a mosquito-borne disease, is an important viral hemorrhagic fever in Africa and South America where it is endemic. Detection of yellow fever virus (YFV) in Africa remains a challenge due to a lack of highly specific tests. The aim of this study was to develop and optimize a rapid detection reverse transcription loop-mediated isothermal amplification (RT-LAMP) for YFV. The RT-LAMP was done isothermally at 62 °C using a real-time turbidimeter that allowed detection within 1h. Specificity of the RT-LAMP was determined using RNA from flaviviruses and other related viruses where only YFV RNA was detected: West Nile virus, dengue viruses, Japanese encephalitis virus, Rift Valley fever virus, and chikungunya virus. In addition, equal sensitivity was also observed when the RT-LAMP and the real-time RT-PCR were compared using YFV-spiked human serum samples with a detection limit of 0.29 PFU/ml. Two Kenyan YFV wild strains showed an equal detection limit as the vaccine strain 17D in this study. The RT-LAMP reduced the time of reaction from 3h to 1h and increased sensitivity tenfold compared to RT-PCR. Therefore, this test offers a simple, rapid and reliable diagnostic tool for yellow fever when there are outbreaks of acute hemorrhagic fever in Kenya and other African countries.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico/métodos , Fiebre Amarilla/diagnóstico , Virus de la Fiebre Amarilla/aislamiento & purificación , África , Humanos , Transcripción Reversa , Sensibilidad y Especificidad , América del Sur , Temperatura , Factores de Tiempo , Fiebre Amarilla/virología
18.
AIDS Res Hum Retroviruses ; 29(8): 1105-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23617327

RESUMEN

A switch of HIV coreceptor usage from CCR5 to CXCR4 occurs in AIDS pathogenesis and may play a critical role in the use of entry inhibitors. To determine the potential usefulness of maraviroc and other CCR5 antagonists among drug-naive and experienced patients in Kenya, the env-C2-V3 gene was successfully sequenced in samples from 176 (98 men and 78 female) consenting subjects between January 2009 and December 2012. In silico CPSSM, webPSSM/, and (ds) Kernel tools were used in predicting coreceptor usage. On the basis of the env V3 loop sequences, 84.1% (148) were reported with R-5 tropism, 4.5% (5) were dual tropic, while 13.4% (23) were of X4 tropism. However, similar to previous studies conducted in Kenya on genetic diversity, HIV-1 subtype A1 (73.9%; 130/176) still remains the most dominant subtype. The high levels of R5 tropism among the studied Kenyan infected populations suggested the potential use of CCR5 antagonists as new therapeutic options in Kenya.


Asunto(s)
Ciclohexanos/uso terapéutico , Proteína gp120 de Envoltorio del VIH/genética , Infecciones por VIH/genética , VIH-1/fisiología , Receptores CCR5/genética , Receptores CXCR4/genética , Triazoles/uso terapéutico , Tropismo Viral , Adolescente , Adulto , Anciano , Antagonistas de los Receptores CCR5 , Niño , Preescolar , Femenino , Infecciones por VIH/virología , Humanos , Kenia , Masculino , Maraviroc , Persona de Mediana Edad , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Adulto Joven
19.
AIDS Res Hum Retroviruses ; 29(2): 400-3, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22916803

RESUMEN

As the AIDS pandemic progresses, an increasingly broad range of genetic diversity continues to be reported within the main (M) group of HIV-1 viruses with viral subtype predominating in specific geographic areas. To determine the genetic diversity of HIV-1 subtypes among Kenyan individuals, the env-C2-V3 gene was successfully sequenced in samples from 176 patients. Analysis of the sequences showed that a majority of them belonged to subtype A1: 73.9% (130/176), followed by C: 10.8% (19/176), D: 10.2% (18/176), and 0.6% (1/176) for G and A2 as pure subtypes while the rest were recombinants of A1/U: 2.3% (4/176) and 0.6% (1/176) each for D/U, A/C/U, and AC. Similar to previous studies conducted in other parts of Kenya, HIV-1 subtype A1 still remains the most predominant subtype while subtype C continues to show an increasing prevalence. Continued surveillance of circulating subtypes of HIV-1 in Kenya is important in determining the evolution of the HIV/AIDS epidemic in Kenya.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Adolescente , Adulto , Estudios Transversales , Femenino , Variación Genética , Genotipo , VIH-1/aislamiento & purificación , Humanos , Kenia/epidemiología , Masculino , Epidemiología Molecular , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Adulto Joven
20.
Health Care Women Int ; 33(7): 595-613, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22681745

RESUMEN

In this study, 50 in-depth interviews were carried out with women from the general population in Thika, Kenya. We explored awareness, attitudes, and behavior toward cervical cancer and screening measures among the women. The concept of the health belief model (HBM) was used to develop the topics for the in-depth interviews. Our findings highlight the lack of awareness of cervical cancer and the benefits of early detection measures as critical barriers that affect women's participation in screening programs. We provide a basis for designing programs that will be acceptable and accessible to a larger population, resulting in a reduced cervical cancer burden.


Asunto(s)
Detección Precoz del Cáncer/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Neoplasias del Cuello Uterino/prevención & control , Frotis Vaginal/estadística & datos numéricos , Adulto , Anciano , Actitud del Personal de Salud , Detección Precoz del Cáncer/psicología , Femenino , Conductas Relacionadas con la Salud , Accesibilidad a los Servicios de Salud , Humanos , Entrevistas como Asunto , Kenia , Tamizaje Masivo , Persona de Mediana Edad , Modelos Psicológicos , Aceptación de la Atención de Salud , Investigación Cualitativa , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Frotis Vaginal/psicología , Adulto Joven
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