Antibacterial properties of Mangifera indica on Staphylococcus aureus

Antibacterial activity of Mangifera indica stem bark extracts was determined using disk diffusion, agar and broth dilution methods. In disk diffusion method, inhibition zone sizes were used to determine the susceptibility of S. aureus to the extracts. The results showed that the stem-bark extracts of M. indica have antimicrobial activity against S. aureus. Methanol extracts showed the highest inhibition zone diameter of 25 mm, followed by ethyl acetate, water and hexane extracts with inhibition zone diameter of 22 mm, 14 mm and 10 mm, respectively. The antibacterial activities of different extracts were found to be concentration dependent, in agar and broth dilution methods. The plant extracts were shown to have a MIC range of 0.62 mg/ml to 4.17 mg/ml, in agar dilution method. Results from the broth dilution method had a MIC range of 0.16 mg/ml to 1.25 mg/ml. The control (ampicillin) was however, more effective than plant extracts since only a concentration of 0.03 mg/ml in agar dilution and 0.001 mg/ml in broth dilution method were effective to inhibit the growth of S. aureus. The extracts were shown to be bacteriostatic at low concentrations. Phytochemical screening of the extracts revealed the presence of phyto-compounds such as alkaloids and tannins which are known to inhibit bacterial growth by different mechanisms from those of synthetic drugs. These phyto-constituents may be responsible for the M. indica antibacterialactivity.Keywords: Staphylococcus aureus, antimicrobial activity, MIC, Phytochemical screening, MBC

Vitamin D: the role of the sunshine vitamin

The importance of vitamin D in physical disorders has been well documented. Deficiency in this vitamin is associated with a wide range of physical and mental disorders that include, heart problems, hypertension, stroke, diabetes, various cancers, and asthma. In mental health vitamin D deficiency is associated with schizophrenia, depression, anxiety, Alzheimer’s disease among others. Risk factors for vitamin D deficiency include darker skin, lack of adequate sun exposure, autoimmune diseases, influenza, old age and the use of certain medicines like anticonvulsants. Vitamin D is likely to play an important role in the management and prevention of various mental health problems. In particular, adequate vitamin D during the perinatal stage is likely to impact positively on the long term mental health of a person

A Vegetation Map of Stamford Farm in Mvurwi, Mashonaland Central Province, Zimbabwe

The factors underlying tree species and tree size class distribution at Stanford Farm in Mvurwi, Zimbabwe were investigated. Quadrats were laid along belt transects running from a hilltop down a vlei leading to a dam. In each quadrat, tree species and height, soil moisture and depth, as well as rockiness were determined. Human disturbance was also assessed through counting the number of stumps per quadrat. The farm recorded a high species diversity with ten different species identified. It was also noted that soil characteristics determined tree species as well as size class distribution. Keywords: Human disturbance, Rockiness, Simpson’s index of diversity, soil depth, soil moisture, tree height, tree  specie

Randomised controlled trial to improve health and reduce substance use in established psychosis (IMPaCT): cost-effectiveness of integrated psychosocial health promotion

Background: There is mounting evidence that people with severe mental illness have unhealthy lifestyles, high rates of cardiovascular and metabolic diseases, and greater risk of early mortality. This study aimed to assess the cost-effectiveness of a health promotion intervention seeking to improve physical health and reduce substance use in people with psychosis. Methods: Participants with a psychotic disorder, aged 18-65 years old and registered on an enhanced care approach programme or equivalent were recruited from community mental health teams in six mental health trusts in England. Participants were randomisation to either standard community mental health team care (treatment as usual) or treatment as usual with an integrated health promotion intervention (IMPaCT). Cost-effectiveness and cost-utility analyses from health and social care and societal perspectives were conducted alongside a cluster randomised controlled trial. Total health and social care costs and total societal costs at 12 and 15 months were calculated as well as cost-effectiveness (incremental cost-effectiveness ratios and cost-effectiveness acceptability curves) at 15 months based on quality of life (SF-36 mental and physical health components, primary outcome measures) and quality adjusted life years (QALYs) using two measures, EQ-5D-3 L and SF-36. Data were analysed using bootstrapped regressions with covariates for relevant baseline variables. Results: At 12-15 months 301 participants had full data needed to be included in the economic evaluation. There were no differences in adjusted health and social care costs (£95, 95% CI -£1410 to £1599) or societal costs (£675, 95% CI -£1039 to £2388) between the intervention and control arms. Similarly, there were no differences between the groups in the SF-36 mental component (−0.80, 95% CI -3.66 to 2.06), SF-36 physical component (−0.68, 95% CI -3.01 to 1.65), QALYs estimated from the SF-36 (−0.00, −0.01 to 0.00) or QALYs estimated from the EQ-5D-3 L (0.00, 95% CI -0.01 to 0.02). Cost-effectiveness acceptability curves for all four outcomes and from both cost perspectives indicate that the probability of the health promotion intervention being cost-effective does not exceed 0.4 for willingness to pay thresholds ranging from £0-£50,000. Conclusions: Alongside no evidence of additional quality of life/clinical benefit, there is also no evidence of cost-effectiveness

Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

A comparative assessment of the quality of age at first sex and age at first marriage reporting in three HIV cohort studies in sub-Saharan Africa

OBJECTIVES: To assess inconsistencies in reported age at first sex (AFS) and age at first marriage (AFM) in three African cohorts, and consider their implications for interpreting trends in sexual and marital debut.METHODS: Data were analysed from population-based cohort studies in Zimbabwe, Uganda and South Africa with 3, 10 and 4 behavioural survey rounds, respectively. Three rounds over a similar time frame were selected from each site for comparative purposes. The consistency of AFS and AFM reports was assessed for each site by comparing responses made by participants in multiple surveys. Respondents were defined as unreliable if less than half of all their age-at-event reports were the same. Kaplan-Meier functions were used to describe the cumulative proportion (1) having had sex and (2) married by age, stratified by sex, birth cohort and site, to compare the influence of reporting inconsistencies on these estimates.RESULTS: Among participants attending all three comparable rounds, the percentage with unreliable AFS reports ranged from 30% among South African women to 56% among Zimbabwean men, with similar patterns observed for AFM. Inclusion of unreliable reports had little effect on estimates of median age-at-event in all sites. There was some evidence from the 1960-9 birth cohort that women in Uganda and both sexes in South Africa reported later AFS as they aged.CONCLUSION: Although reporting quality is unlikely to affect comparisons of AFS and AFM between settings, care should be taken not to overinterpret small changes in reported age-at-event over time within each site

Leadership emergence in face-to-face and virtual teams : a multi-level model with agent-based simulations, quasi-experimental and experimental tests

With leadership as a major predictor of team performance in both face-to-face and virtual teams, research on differences in leadership emergence in these contexts seems warranted. We offer a multi-level model analyzing the roles of degree of team virtuality and density of social network ties as boundary conditions on leadership emergence, viewed as a fundamentally social–cognitive process. Using agent-based modeling and simulations, our results suggest that virtuality moderates the relationships between cognitive ability, extraversion, and self-efficacy (as independent variables) and leadership emergence (as dependent variable); and density of network ties serves as a moderator for the associations of cognitive ability and self-efficacy with leadership emergence. Subsequent quasi-experimental and experimental tests support the role of density of network ties as a moderator for the association of extraversion with leadership emergence. Implications of these findings and future paths for research bridging the fields of leadership, team virtuality and social networks are discussed