AAS Open Research
EISSN : 25159321
Current Publisher: F1000 Research, Ltd. (10.12688)
Total articles ≅ 85
Latest articles in this journal
AAS Open Research; doi:10.12688/aasopenres
AAS Open Research, Volume 1; doi:10.12688/aasopenres.12848.2
Abstract:Background: A number of studies have investigated transgenerational effects of parental post-traumatic stress disorder (PTSD) and its repercussions for offspring. Few studies however, have looked at this issue in the African context. Methods: The present study addresses this gap by utilizing a Pearson correlation matrix to investigate symptom severity within the three Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) PTSD symptom domains in mothers exposed to the genocide against the Tutsi in Rwanda (n=25) and offspring (n=25), and an ethnically matched set of controls (n=50) who were outside of Rwanda during the 1994 genocide. All mothers were pregnant with the offspring included in the study during the time of the genocide. Results: Total PTS score was significantly (pNR3C1) locus, an important stress modulating gene, and PTSD symptom domains, finding an association between DNA methylation and re-experiencing among genocide-exposed mothers that exceeded any other observed associations by approximately two-fold. Conclusions: This is the first report, to our knowledge, of a symptom-based analysis of transgenerational transmission of PTSD in sub-Saharan Africa. These findings can be leveraged to inform further mechanistic and treatment research for PTSD.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.12947.2
Abstract:Background: There is limited data from Africa on the effect of pre- and post-natal growth and infant feeding on later body composition. This study's aim was to investigate the effect of birth weight, exclusive breastfeeding and infant growth on adolescent body composition, using data from a Ugandan birth cohort. Methods: Data was collected prenatally from pregnant women and prospectively from their resulting live offspring. Data on body composition (fat mass index [FMI] and fat free mass index [FFMI]) was collected from 10- and 11-year olds. Linear regression was used to assess the effect of birth weight, exclusive breastfeeding and infant growth on FMI and FFMI, adjusting for confounders. Results: 177 adolescents with a median age of 10.1 years were included in analysis, with mean FMI 2.9 kg/m2 (standard deviation (SD) 1.2), mean FFMI 12.8 kg/m2 (SD 1.4) and mean birth weight 3.2 kg (SD 0.5). 90 (50.9%) were male and 110 (63.2%) were exclusively breastfeeding at six weeks of age. Birth weight was associated with FMI in adolescence (regression coefficient β= 0.66 per kg increase in birth weight, 95% confidence interval (CI) (0.04, 1.29), P=0.02), while exclusive breastfeeding (β= -0.43, 95% CI (-1.06, 0.19), P=0.12), growth 0-6 months (β= 0.24 95% CI (-0.43, 0.92), P=0.48) and growth 6-12 months (β= 0.61, 95% CI (-0.23, 1.46), P=0.11) were not associated with FMI among adolescents. Birth weight (β= 0.91, 95% CI (0.17, 1.65), P=0.01) was associated with FFMI in adolescence. Exclusive breastfeeding (β= 0.17, 95% CI (-0.60, 0.94), P=0.62), growth 0-6 months (β= 0.56, 95% CI (-0.20, 1.33), P= 0.10), and growth 6-12 months (β= -0.02, 95% CI (-1.02, 0.99), P=0.97) were not associated with FFMI. Conclusions: Birth weight predicted body composition parameters in Ugandan early adolescents, however, exclusive breastfeeding at six weeks of age and growth in infancy did not.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.12953.2
Abstract:Background: In recent years, a profound transformation has been observed in the eating habits of the populations of African cities, induced by accelerated socioeconomic and demographic growth. In Senegal, these changes have manifested in the proliferation of collective informal catering enterprises, such as the ‘dibiteries’, where the roasted meat of sheep is prepared and sold. The rise of the average household income has contributed substantially to increasing levels of meat consumption, leading to the expansion of the dibiteries. The purpose of the current work was to evaluate the managerial performance of these establishments in Dakar, Senegal. Methods: To achieve this, a cross-sectional study was conducted among 152 dibiteries using a questionnaire. Efficiency scores were determined via the data envelopment analysis method. The pure technical scores thereby obtained were subsequently used as dependent variables in a Tobit model to identify the socioeconomic determinants of dibiterie efficiency. Results: The resulting average score of the dibiteries suggests that the majority are operating inefficiently (79.6%). Moreover, it was demonstrated that this inefficiency seems to be related to scale rather than technical issues. However, few of the dibiteries assessed (20.4%) were nevertheless in a situation of constant scale economy. Among the socioeconomic variables tested, experience, leadership (family or individual-run), the ownership status of the restaurant building (own or lease) and the type of workforce (family, recruited, mixed or without) had a significant impact on the efficiency of the establishments. Conclusions: The scale economy and waste reduction in food production can result in economic gains that can in turn be used in the safety of finished products. Indeed, by following best practices, dibiteries can make gains which could be used to invest in good hygiene practices on handwashing, cleaning and disinfecting grilling tools, optimizing work space and training staff.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.12967.2
Abstract:Background: This study evaluated the effect of Beta vulgaris (beetroot) smoothie on some biochemical parameters on dimethyl 2,2-dichlorovinyl phosphate (DDVP, known as dichlorvos)-exposed albino Wistar rats. Methods: A total of 30 rats of both sexes were grouped into five groups of six animals each. Group I served as the negative control and were not exposed to dichlorvos. Group II served as the positive control and were exposed to dichlorvos but received no smoothie. Group III received 500 mg/kg body weight beetroot smoothie and was not exposed to dichlorvos. Groups IV and V were exposed to dichlorvos but received beetroot before and after exposure, respectively. At the end of the 6-week experiment, the animals were euthanized, the blood samples collected for some biochemical assays while the organs (kidney and liver) were harvested and subjected to histopathological examination. Results: From the biochemical assay, it was observed that the beetroot smoothies regulated and significantly reduced the elevated levels of AST, ALT, urea and creatinine observed in the animals that were exposed to dichlorvos. Additionally, the beetroot was able to regenerate the liver and kidney organs that were damaged on exposure to dichlorvos. Conclusion: This study concluded that beetroot smoothie possesses hepato-protective, hepato-curative as well as nephro-curative properties.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.13027.1
Abstract:Background: It is projected that by 2030, 70% of all cancer related deaths will occur in low-middle income countries. However, data on the state of cancer in most African countries is scanty. Cancer estimates for Kenya are based on the Nairobi and Eldoret cancer registries, leaving most parts of the country unrepresented. Lacking national coverage, these data do not accurately reflect Kenya’s cancer burden. The paucity of reliable data impedes formulation of effective cancer control strategies and cancer research prioritization. Here, we report the findings of a retrospective study of the cancer state in Meru County, Kenya. Methods: A retrospective analysis of patient files at Meru hospice was carried out. 2349 cancer cases seen at the Meru hospice between 2003 and 2018 were analyzed. Data abstracted from the records included patient age, gender and cancer type. The abstracted data was analyzed by descriptive statistics. Results: Our results indicate that cancer is almost evenly distributed across genders, with men accounting for 49% and women 51%. Stomach cancer rates are strikingly elevated and equal to those in countries with the highest stomach cancer rates globally – making it the commonest cancer in this region (14%). Among men, the most common cancers affect the prostate (18%), stomach (17%), esophagus (14%), head & neck (12%), liver (8%) and colorectum (5%). Among women, the commonest are cancers of the breast (22%), cervix (20%), stomach (11%), esophagus (8%), head & neck (6%) and liver (5%). Breast cancer occurs at a notably early age, with 20% of those affected aged below 40. Lung cancer rates are notably low in this region (1.3%) relative to world estimates. Conclusion: Cancer distribution in Meru is nearly even between sexes. Our analysis suggests that the Meru region is a stomach cancer hotspot and that it also experiences elevated esophageal cancer levels.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.13022.1
Abstract:Background: Toxoplasma gondii is an obligate, intracellular, apicomplexan parasite that causes toxoplasmosis. Although the global prevalence of toxoplasmosis has been estimated to be approximately 30%, there is limited seroprevalence data in Ghana, with a dearth of information on the impact of T. gondii on haematological parameters in exposed persons. Methods: Questionnaires were administered to 300 consenting individuals to obtain demographic information and assessment of their risk of exposure to T. gondii. Using anti-T. gondii IgG/IgM combo test kits, seropositivity to parasite-specific IgG and/or IgM was determined. A haematological analyser was used to measure haematological parameters. Results: The participants included 58 males and 242 females, and ranged in age from 6 months to 84 years, with a median age of 27 years. There was an overall seroprevalence of 50.3% (n=151), with 49.7% (n=149) of the study participants seropositive for IgG and 1% (n=3) testing positive for IgM. Furthermore, the observed seroprevalence among pregnant women was 56.4% (n=62). With regards to the different communities in which the hospitals were located, a seroprevalence of 55.6% was observed in the rural community, 50.6% in the peri-urban community and 47.1% in the urban community. The study identified cat ownership, contact with cat litter [RR (95% CI: 1.76 (1.23-2.53), 1.66 (1.03-2.67), 1.25(1.00-1.57)] and age (p Conclusions: About half of the study population, including a significant number of women of reproductive age carried antibodies against T. gondii, raising questions about the risk of congenital toxoplasmosis, as well as possible links to anaemia. We, therefore, recommend that screening for Toxoplasma gondii be included in the routine screening of pregnant women seeking antenatal care.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.12986.1
Abstract:Background: Trypanosoma brucei, a causative agent of African Trypanosomiasis, is known to cross the blood brain barrier during the second stage of the disease. It was previously suggested that this parasite crosses the blood brain barrier in a manner similar to that of lymphocytes. This would imply that trypanosomes possess integrins that are required to interact with adhesion molecules located on the blood brain barrier microvascular endothelial cells, as a first step in traversal. To date, no T. brucei integrin has been described. However, one T. brucei putative FG-GAP repeat containing protein (typical of integrins) encoded by the Tb927.11.720 gene, was predicted to be involved in cell-cell/cell-matrix adhesion. Therefore, this study sought to characterize a putative FG-GAP repeat containing protein (FG-GAP RCP) and to determine its cellular localization as a basis for further exploration of its potential role in cell-cell or cell-matrix adhesion. Methods: In this study, we successfully cloned, characterized, expressed and localized this protein using antibodies we produced against its VCBS domain in T. brucei. Results: Contrary to what we initially suspected, our data showed that this protein is localized to the mitochondria but not the plasma membrane. Our data showed that it contains putative calcium binding motifs within the FG-GAP repeats suggesting it could be involved in calcium signaling/binding in the mitochondrion of T. brucei. Conclusion: Based on its localization we conclude that this protein is unlikely to be a trypanosomal integrin and thus that it may not be involved in traversal of the blood brain barrier. However, it could be involved in calcium signaling in the mitochondrion.
AAS Open Research, Volume 1; doi:10.12688/aasopenres.12910.5
Abstract:Background: Cancer in Africa is an emerging health problem. In Kenya it ranks third as a cause of death after infectious and cardiovascular diseases. Nearly 31% of the total cancer burden in sub-Saharan Africa is attributable to infectious agents. Information on cancer burden is scanty in Kenya and this study aimed to provide comprehensive hospital based data to inform policies. Method: A cross-sectional retrospective survey was conducted at Kenyatta National Hospital (KNH) and Moi Teaching and Referral Hospital (MTRH) from January 2008 to December 2012. Data was obtained from the patients files and the study was approved by the KNH/University of Nairobi and MTRH Ethics and Research Committees. Results: In KNH, the top five cancers were: cervical (62, 12.4%), breast (59, 11.8%), colorectal (31, 6.2%), chronic leukemia (27, 5.4%) and stomach cancer (26, 5.2%). Some 154 (30.8%) of these cancers were associated with infectious agents, while an estimated 138 (27.6%) were attributable to infections. Cancers of the cervix (62, 12.4%), stomach (26, 5.2%) and nasopharynx (17, 3.4%) were the commonest infection-associated cancers. In MTRH, the five common types of cancers were Kaposi’s sarcoma (93, 18.6%), breast (77, 15.4%), cervical (41, 8.2%), non-Hodgkin’s lymphoma (37, 7.4%) and colorectal, chronic leukemia and esophageal cancer all with 27 (5.4%). Some 241 (48.2%) of these cancers were associated with infectious agents, while an estimated 222 (44.4%) were attributable to infections. Kaposi’s sarcoma (93, 18.6%), cancer of the cervix (41, 8.2%) and non-Hodgkin’s lymphoma (37, 7.4%) were the commonest infection-associated cancers. Conclusion: Our results suggest that 30.8% and 48.2% of the total cancer cases sampled in KNH and MTRH respectively were associated with infectious agents, while 27.6% and 44.4% were attributable to infections in the two hospitals respectively. Reducing the burden of infection-attributable cancers can translate to a reduction of the overall cancer burden.
AAS Open Research, Volume 2; doi:10.12688/aasopenres.13021.1
Abstract:Background: Major constraints to camel production include pests and diseases. In northern Kenya, little information is available about disease pathogens circulating in one-humped camels (Camelus dromedarius) or their possible transmission by the camel haematophagous ectoparasite, Hippobosca camelina, commonly known as camel ked or camel fly. This study aimed to: (i) identify the presence of potentially insect-vectored pathogens in camels and camel keds, and (ii) assess the potential utility of keds for xenodiagnosis of camel disease pathogens that they may not vector. Methods: In Laisamis, northern Kenya, camel blood samples (n = 249) and camel keds (n = 117) were randomly collected from camels. All samples were screened for trypanosomal and camelpox DNA by PCR, and for Anaplasma, Ehrlichia, Brucella, Coxiella, Theileria, and Babesia by PCR coupled with high-resolution melting (PCR-HRM) analysis. Results: In camels, we detected Trypanosoma vivax (102/249) (41%), Trypanosoma evansi (3/249) (1.2%), and “Candidatus Anaplasma camelii” (137/200) (68.5%). In camel keds, we also detected T. vivax (53/117) (45.3%), T. evansi (3/117) (2.56%), Trypanosoma melophagium (1/117) (0.4%), and “Candidatus Anaplasma camelii” (19/117) (16.24 %). Piroplasms (Theileria spp. and Babesia spp.), Coxiella burnetii, Brucella spp., Ehrlichia spp., and camel pox were not detected in any samples. Conclusions: This study reveals the presence of epizootic pathogens in camels from northern Kenya. Furthermore, the presence of the same pathogens in camels and in keds collected from sampled camels suggests the potential use of these flies in xenodiagnosis of haemopathogens circulating in camels.