Molecular cloning and phylogenetic analysis of human immunodeficiency virus type 1 subtype C: a set of 23 full-length clones from Botswana. (1/208)

To better understand the virological aspect of the expanding AIDS epidemic in southern Africa, a set of 23 near-full-length clones of human immunodeficiency virus type 1 (HIV-1) representing eight AIDS patients from Botswana were sequenced and analyzed phylogenetically. All study viruses from Botswana belonged to HIV-1 subtype C. The interpatient diversity of the clones from Botswana was higher than among full-length isolates of subtype B or among a set of full-length HIV-1 genomes of subtype C from India (mean value of 9. 1% versus 6.5 and 4.3%, respectively; P < 0.0001 for both comparisons). Similar results were observed in all genes across the entire viral genome. We suggest that the high level of HIV-1 diversity might be a typical feature of the subtype C epidemic in southern Africa. The reason or reasons for this diversity are unclear, but may include an altered replication efficiency of HIV-1 subtype C and/or the multiple introduction of different subtype C viruses.  (+info)

Elevated tumor necrosis factor-alpha activation of human immunodeficiency virus type 1 subtype C in Southern Africa is associated with an NF-kappaB enhancer gain-of-function. (2/208)

The human immunodeficiency virus type 1 (HIV-1) epidemic within southern Africa is predominantly associated with the HIV-1C subtype. Functional analysis of the enhancer region within the long terminal repeat (LTR) indicates that HIV-1C isolates have >/=3 NF-kappaB binding sites, unlike other subtypes, which have only 1 or 2 sites. A correlation was shown between NF-kappaB enhancer configuration and responsiveness to the proinflammatory cytokine tumor necrosis factor (TNF)-alpha within the context of naturally occurring subtype LTRs, subtype-specific NF-kappaB enhancer regions cloned upstream of an isogenic HXB2 core promoter or a heterologous SV40 minimal promoter, and full-genome subtype clones. In all cases, TNF-alpha activation was correlated with the subtype configuration of the NF-kappaB enhancer. Whether the naturally occurring gain-of-function in the NF-kappaB enhancer of HIV-1C observed in this study can provide a selective advantage for the virus in vivo remains to be determined and warrants further study.  (+info)

Morbidity and health care utilisation among elderly people in Mmankgodi village, Botswana. (3/208)

OBJECTIVE: To evaluate the health status among the elderly in a village in Botswana and their pattern of health care utilisation. DESIGN: A descriptive study where all persons 60 years and older were invited to participate, including a medical examination, laboratory testing and a questionnaire aiming at gathering sociodemographic data. SETTING: Mmankgodi village of Botswana. SUBJECTS: 419 persons were identified as elderly in the village, out of which 337 were included. MAIN OUTCOME MEASURES: The general medical examination also included eye status, vision and hearing tests, nutritional status, blood pressure and registering of physical disabilities. Laboratory tests included haemoglobin, blood glucose, HIV antibodies and serum lipids. The questionnaire contained questions regarding family and civil status, self assessed general health, health problems experienced during the previous month, and health care utilisation. Questions also pertained to smoking, taking snuff, and alcohol consumption. RESULTS: A majority (75%) of the elderly experienced good or only somewhat reduced health, while one quarter suffered more serious health problems. The most frequent health problems were related to the musculoskeletal system. Eye diseases, including cataract and blindness, were also common. The concentration of serum lipids is lower than the one found in the elderly population of Norway. Nutritional status indicated a relatively high prevalence (7%) of malnutrition. The majority of men were still married (87%), while most women were widowed (71%). Women reported more health problems than men, and they also reported more worries regarding their own life situation. There is a tendency for the elderly to seek assistance from the established clinics and other health facilities for their health problems. Worries are either kept to themselves or advice is sought from relatives. Traditional healers were not often consulted for health problems or worries. CONCLUSIONS: Major health problems were identified among the elderly in this geographical area of Botswana. There is presently no health programme in Botswana aimed at the elderly. Some of the diseases and conditions found in this study could easily be identified and treated in the present health system through a health care programme.  (+info)

Microscopic identification of asbestos fibres associated with African clay crafts manufacture. (4/208)

The use of asbestos in manufacturing is a world-wide phenomenon, not just confined to the developed world. The activity described below shows that there are similar problems in the third world which need to be tackled. A sample of white fibrous material used in pot making by women in a village of Botswana was provided for analysis. The identification of fibres was carried out using established analytical and vibrational microspectroscopic methods. The occupational hygiene implications and the measures which may need to be taken in order to improve the safety of the pot making process are discussed in this article.  (+info)

Characterization of strains of Mycoplasma mycoides subsp. mycoides small colony type isolated from recent outbreaks of contagious bovine pleuropneumonia in Botswana and Tanzania: evidence for a new biotype. (5/208)

Four strains of Mycoplasma mycoides subsp. mycoides small colony type (MmmSC) isolated from recent outbreaks of contagious bovine pleuropneumonia (CBPP) in Africa have been investigated. One Botswanan strain, M375, displayed numerous and significant phenotypic differences from both contemporary field isolates and older field and vaccine strains (African, Australian, and European strains dating back to 1936). Differences include altered morphology, reduced capsular polysaccharide production, high sensitivity to MmmSC rabbit hyperimmune antisera in vitro, and unique polymorphisms following immunoblotting. While insertion sequence analysis using IS1634 clearly indicates a close evolutionary relationship to west African strains, hybridization with IS1296 shows the absence of a band present in all other strains of MmmSC examined. The data suggest that a deletion has occurred in strain M375, which may explain its altered phenotype, including poor growth in vitro and a relative inability to cause septicemia in mice. These characteristics are also exhibited by Mycoplasma capricolum subsp. capripneumoniae (causal agent of contagious caprine pleuropneumonia [CCPP]), against which M375 antiserum exhibited some activity in vitro (unique among the various MmmSC antisera tested). These findings may have evolutionary implications, since CCPP is believed to be lung specific and without a septicemic phase (unlike CBPP). Since M375 was isolated from a clinical case of CBPP, this novel biotype may be fairly widespread but not normally isolated due to difficulty of culture and/or a potentially altered disease syndrome. Bovine convalescent antisera (obtained from contemporary naturally infected cattle in Botswana) were active against strain M375 in an in vitro growth inhibition test but not against any other strains of MmmSC tested. There exists the possibility therefore, that strain M375 may possess a set of protective antigens different from those of other strains of MmmSC (including vaccine strains). These findings have implications for the control of the current CBPP epidemic in Africa.  (+info)

Molecular cloning and biological characterization of full-length HIV-1 subtype C from Botswana. (6/208)

Human immunodeficiency virus type 1 (HIV-1) subtype C is now responsible for more than half of all HIV-1 infections in the global epidemic and for the high levels of HIV-1 prevalence in southern Africa. To facilitate studies of the biological nature and the underlying molecular determinants of this virus, we constructed eight full-length proviral clones from two asymptomatic and three AIDS patients infected with HIV-1 subtype C from Botswana. Analysis of viral lysates showed that Gag, Pol, and Env structural proteins were present in the virions. In four clones, the analysis suggested inefficient envelope glycoprotein processing. Nucleotide sequence analysis of the eight clones did not reveal frameshifts, deletions, premature truncations, or translational stop codons in any structural, regulatory, or accessory genes. None of the subtype C clones were replication competent in donor peripheral blood mononuclear cells (PBMCs), macrophages, Jurkat(tat) cells, or U87. CD4.CCR5 cells. However, infection by two clones could be rescued by complementation with a functional subtype C envelope clone, resulting in a productive infection of PBMCs, macrophages, and U87. CD4.CCR5 cells.  (+info)

Molecular and conventional epidemiology of Mycobacterium tuberculosis in Botswana: a population-based prospective study of 301 pulmonary tuberculosis patients. (7/208)

Little is known about patterns of tuberculosis (TB) transmission among populations in developing countries with high rates of TB and human immunodeficiency virus (HIV) infection. To examine patterns of TB transmission in such a setting, we performed a population-based DNA fingerprinting study among TB patients in Botswana. Between January 1997 and July 1998, TB patients from four communities in Botswana were interviewed and offered HIV testing. Their Mycobacterium tuberculosis isolates underwent DNA fingerprinting using IS6110 restriction fragment length polymorphism, and those with matching fingerprints were reinterviewed. DNA fingerprints with >5 bands were considered clustered if they were either identical or differed by at most one band, while DNA fingerprints with < or =5 bands were considered clustered only if they were identical. TB isolates of 125 (42%) of the 301 patients with completed interviews and DNA fingerprints fell into 20 different clusters of 2 to 16 patients. HIV status was not associated with clustering. Prior imprisonment was the only statistically significant risk factor for clustering (risk ratio, 1.5; 95% confidence interval, 1.1 to 2.0). In three communities where the majority of eligible patients were enrolled, 26 (11%) of 243 patients overall and 26 (25%) of 104 clustered patients shared both a DNA fingerprint and strong antecedent epidemiologic link. Most of the increasing TB burden in Botswana may be attributable to reactivation of latent infection, but steps should be taken to control ongoing transmission in congregate settings. DNA fingerprinting helps determine loci of TB transmission in the community.  (+info)

Shigella and Salmonella strains isolated from children under 5 years in Gaborone, Botswana, and their antibiotic susceptibility patterns. (8/208)

We isolated Shigella from 43/221 (21%) and Salmonella 8/221 (3%) rectal swabs from children under 5 years with diarrhoea, and found Shigella in two of 100 specimens from children without diarrhoea. Sh. boydii (13%) was the most prevalent Shigella species followed by Sh. flexneri (6%) and Sh. sonnei (2%). The prevalence of various types of Sh. boydii was type 7, 5%; type 9, 3%; type 12 and 16, 2%; and type 18, 1%. Other Shigella serotypes encountered were Sh. flexneri type 6 (4%), type 4 (2%), with Sh. sonnei phase II isolated from 2% of the specimens. The Salmonella species were S. typhimurium and S. paratyphi. The high rate of isolation of Shigella species from children with diarrhoea is indicative of a definite role of this enteropathogen in causing endemic diarrhoea in Gaborone, Botswana. Antibiograms of the predominant isolates showed that most Shigella species were resistant to ampicillin but susceptible to chloramphenicol, and with the exception of Sh. flexneri type 6, also susceptible to gentamicin. The Salmonella species were susceptible to chloramphenicol, collistin-sulphate, gentamicin, cotrimoxazole, and ampicillin.  (+info)