Determination of dichlorvos residue levels in vegetables sold in Lusaka, Zambia

Introduction: Small scale and large scale farmers around Lusaka, the capital city of Zambia grow vegetables using intensive agriculture methods to satisfy the ever increasing demand. To ensure maximum yield they apply various types of pesticides to control pests and diseases that attack these vegetables. Organophosphate pesticides are widely used in agriculture for the control of various insect pests mainly in developing countries. The purpose of the study was to determine the residual levels of the most commonly used organophosphate, 2, 2-Dichlorovinyl dimethyl phosphate, in three commonestvegetables supplied at various markets around Lusaka. Methods: Samples of 9 bunches of rape, 14 bunches lettuce and 15 rolls cabbage were randomly picked from several study sites around Lusaka. The vegetables were chopped into small pieces which were chemically treated to get methanol extracts. The extracts were then dissolved in an appropriate solvent and using Shimadzu High Performance Liquid Chromatography-Ultra-violet detector (HPLC-UV) levels of 2, 2-Dichlorovinyl dimethyl phosphate were determined. Results: The analysis showed that the average levels of dichlorvos were significantly above the maximum accepted limit as set by Zambian Food and Drugs Act on vegetables. Conclusion: Locally grown vegetables from around Lusaka have higher than maximum acceptable limits. This may have implications on human health as the cumulative effect of organophosphates in human body has potential to cause long term health problems.Pan African Medical Journal 2016; 2

Antihyperglycemic and Antihyperlipidemic Effects of Aqueous Extracts of Lannea edulis in Alloxan-Induced Diabetic Rats

Lannea edulis (Sond.) Engl. commonly known as wild grape is used traditionally for the treatment of diabetes. It is only found in Eastern and Southern Africa. Phytochemical screening, antihyperglycemic and antihyperlipidemic effects of aqueous extracts of L. edulis in alloxan induced diabetic rats were carried out. We report herein the findings of this research work. Lannea edulis crude aqueous extracts were obtained by hot infusion and evaporation method. Phytochemical screening was carried out and subsequently toxicity studies of the aqueous extracts were performed to establish the Lethal Dose 50 (LD50) in albino rats. Alloxan monohydrate was used to induce diabetes in the rats. Lannea edulis positive control group doses of 100, 300, and 500 mg/kg were administered to 3 groups for 14 days. The positive control group was administered 5 mg/kg of glibenclamide. The negative and normal control groups were administered distilled water. To determine fasting blood glucose, blood was drawn on days 0, 1, 3, 5, 7, and 14 while it was drawn on days 0 and 14 for the determination of lipids. Phytochemical screening revealed the presence of flavonoids, saponins, tannins, cardiac glycosides, alkaloids and steroids. L. edulis diabetic positive control groups showed significant (P < 0.05) dose dependent reductions in fasting blood glucose levels. When day 0 mean blood glucose levels were compared to day 3 mean blood glucose levels of their respective groups, the 300 mg/kg L. edulis group showed a 23.3% drop and the 500 mg/kg L. edulis group showed a 52.6% drop. The 100 mg/kg L. edulis diabetic positive control group showed a 25.1% drop by day 5, the day on which it showed statistical significance (P < 0.05) compared to the diabetic control. In addition, administration of aqueous extracts of L. edulis to diabetic rats for 14 days significantly decreased (P < 0.05) the levels of serum total cholesterol, triglycerides, Low Density Lipoprotein (LDL) and Very Low Density Lipoprotein (VLDL) whilst increasing the levels of High Density Lipoprotein (HDL), when compared to the diabetic control group. It was concluded that L. edulis showed significant and dose dependent antihyperglycemic and antihyperlipidemic effects thus confirming its traditional use

Aphrodisiac Properties of Mutimba Vula and Mwana Apeluke Herbs sold in Lusaka, Zambia

Background: Male potency has been a talk of many years since humanity existed and the use of various kinds of substances to stimulate sexual desire has been done for many years. Many plant-based concoctions have been released on the Zambian market for consumption without scientifically proven results or effects. Herbalists, Traditional health practitioners (THPs) have put up many advertisements to spread their market base but all the same without any proven results to show to would-be customers to use a particular product. Two local herbal extracts, Mutimba vula (MTV) and Mwana apeluke (MWN) were studied for the presence of medicinally active components and for their sexual behaviour effects in male rats.Aim of the study: The main objective of this research work was to determine aphrodisiac properties of MTV and MWN aqueous herbal extracts.Methodology: Phytochemical screening to determine presence of medicinally active components was performed following standard guidelines. Thereafter, 3 g each of dried powder of MTV and MWN were soaked in 250 mL of distilled water for 3 hours for extraction of active ingredients. Two concentrations, high and low doses of the herbal extracts were administered orally to the treatment groups for 21 days followed by sexual behaviour analysis. Concentration of testosterone in blood samples was determined using a Testosterone Enzyme-Linked Immunosorbent Assay (ELISA) test.Results: Herbal extracts showed varying amounts of saponins, tannins, flavonoids, alkaloids and glycosides. The mounting frequency (p= 0.039), intromission frequency (p= 0.032) and penile erections increased (p= 0.001) significantly indicating enhanced sexual activity in animals treated with the plant extracts. The results indicated that there was no dose-dependent relationship between serum Testosterone levels and the treatment groups (p= 0.061).Conclusion: It was established that oral administration of Mutimba vula and Mwana apeluke caused increased sexual performance in rats. However, more studies are needed to exploit the possible mode of action.Key Words: Aphrodisiacs, potency, Mutimba vula, Mwana apeluke, Testosteron

Immunogenicity of rotavirus vaccine (RotarixTM) in infants with environmental enteric dysfunction.

Deployment of rotavirus vaccines has contributed to significant declines in diarrheal morbidity and mortality globally. Unfortunately, vaccine performance in low-middle income countries (LMICs) is generally lower than in developed countries. The cause for this has been associated with several host and maternal factors including poor water sanitation and hygiene (WASH) status, which are predominant in LMICs. More recently, environmental enteric dysfunction (EED) has specifically been hypothesized to contribute to poor vaccine uptake and response. The aim of this study was to examine the association between serological biomarkers of EED and seroconversion to rotavirus vaccine in Zambian infants.This was a retrospective cohort study of 142 infants who had been fully immunized with Rotarix™, and had known seroconversion status. Seroconversion was defined as 4-fold or more increase in rotavirus-specific IgA titres between pre-vaccination and one month post-dose two vaccination. We performed ELISA assays to assess soluble CD14 (sCD14), Endotoxin Core IgG Antibodies (EndoCAb), intestinal fatty acid binding protein (i-FABP) and Zonulin according to the manufacturers protocols. Generalised linear model with family-poisson, link-log and robust standard error was used to estimate the independent effects of biomarkers on seroconversion adjusting for important cofounders.The median concentration of Zonulin, Soluble CD14, EndoCaB, and IFABP were 209.3 (IQR = 39.7, 395.1), 21.5 (IQR = 21.5, 21.5), 0.3 (IQR = 0.3, 0.3), and 107.7 (IQR = 6.4, 1141.4) respectively. In multivariable analyses adjusting for the independent effect of other biomarkers and confounders (i.e. age of child at vaccination, breast-milk anti-rotavirus IgA, infant serum anti-rotavirus IgG, and IgA seropositivity at baseline), there was strong evidence of about 24% increase in seroconversion due to doubling Zonulin concentration (Adjusted risk ratio (aRR) = 1.24; 95% CI = 1.12 to1.37; p<0.0001). Similarly, we found about 7% increase in seroconversion due to doubling IFABP concentration (aRR = 1.07; 95% CI = 1.02 to 1.13; p = 0.006).We found that high levels of zonulin and IFABP played a role in seroconversion. It is plausible that increased gut permeability in EED allows greater uptake of the live virus within the vaccine, but later consequences result in deleterious local structural distortions and malabsorption syndromes

Medical School Admissions: A Review of Global Practices, Predictive Validity, and Practice Points for Africa

Background: Processes for selection of candidates into medical schools vary globally. Knowledge of the predictive validity of a selection method is important for policy revision. Aim: To survey the practices used by medical schools to select students and their predictive validity. Methods: Search terms developed from the research problem were used to search Google Scholar, PubMed, and Educational Resources Information Centre (ERIC). These were “medical school,” “predictive validity,” “success,” “academic achievement” “admission criteria,” and “student selection.” Retrieved articles were screened for relevance and sorted according to countries ofpublication. Authors narratively reviewed the articles from each country and collated the findings. Best practices were recommended for African-based medical schools. Results: Articles retrieved from 14 countries were included in the review. USA, Canada, UK, Australia, and New Zealand operate&nbsp; centralized medical school admission programs and administer nationwide admission tests. These tests cover cognitive and non-cognitive domains. The validity of these tests in predicting medical school success were extensively studied and reported. Other countries do not operate centralized medical school admission programs. Most of these rely on cognitive excellence to select students. Few reports are available on the validity of selection practices in Africa. Most rely on cognitive excellence which highly predicted academic success during preclinical studies. Predictivity decreased during clinical phases and non-cognitive variables&nbsp; became better predictors of success. Conclusion: Medical school admission processes should consider cognitive and non-cognitive factors. With non-cognitive factors,&nbsp; candidates with right attitudes are selected. African countries should align their practices to that of Western countries. Keywords: Admission, undergraduate medical education, predictive value of tests, selection criteria, educational achievemen

Independent effects of markers of environmetal enteric dysfunction on seroconversion post dose 2 among rotavirus vaccinated infants aged 6–11 weeks.

<p>Independent effects of markers of environmetal enteric dysfunction on seroconversion post dose 2 among rotavirus vaccinated infants aged 6–11 weeks.</p

Seroconversion at post dose 2 by environmental enteric dysfunction status and key infant and maternal factors.

<p>Seroconversion at post dose 2 by environmental enteric dysfunction status and key infant and maternal factors.</p

Infant recruitment and sample selection flow chart.

<p>Infant recruitment and sample selection flow chart.</p