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.

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

Introduction

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.

Methods

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.

Results

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).

Conclusion

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.

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.

Development of a curriculum for training in One Health analytical epidemiology at the University of Zambia

Recently, the world has witnessed emergence of novel diseases such as avian influenza, HIV and AIDS, West Nile Virus and Ebola. The evolution of these pathogens has been facilitated mainly by a constantly evolving animal-human interface. Whilst infectious disease control was previously conceptualised as either public health or animal health related issues, the distinction between disciplinary foci have been blurred by multiple causal factors that clearly traverse traditional disciplinary divides. These multiple evolutionary pressures have included changes in land use, ecosystems, human-livestock-wildlife interactions and antibiotic use, representing novel routes for pathogen emergence. With the growing realisation that pathogens do not respect traditional epistemological divides, the ‘One Health’ initiative has emerged to advocate for closer collaboration across the health disciplines and has provided a new agenda for health education. Against this background, the One Health Analytical Epidemiology course was developed under the auspices of the Southern African Centre for Infectious Diseases Surveillance by staff from the University of Zambia with collaborators from the London School of Hygiene and Tropical Medicine and the Royal Veterinary College in London. The course is aimed at equipping scientists with multidisciplinary skill sets to match the contemporary challenges of human, animal and zoonotic disease prevention and control. Epidemiology is an important discipline for both public and animal health. Therefore, this two-year programme has been developed to generate a cadre of epidemiologists with a broad understanding of disease control and prevention and will be able to conceptualise and design holistic programs for informing health and disease control policy decisions.

4alpha-Phorbol negates the inhibitory effects of phorbol-12-myristate-13-acetate on human cilia and alters the phosphorylation of PKC

In medium 199, ciliary beat frequency (CBF) in human nasal epithelium declines to 60% of baseline by 2 h and 1 nM phorbol-12-myristate-13-acetate (PMA) doubles the rate of decline by activating protein kinase C (PKC). We find that a reported negative control for PMA, 4alpha-phorbol (1 pM-1 nM)+/-1 nM PMA, not only maintains CBF at baseline, but arrests a pre-existing PMA-induced decline in CBF and alters the profile of multiple phosphorylated PKC species. Thus, 4alpha-phorbol not only potently prevents PMA from inhibiting CBF but also has potent effects on the phosphorylation of PKC.

'Behind walls': a study of HIV risk behaviours and seroprevalence in prisons in Zambia

Inmate populations include a large number of individuals at risk of HIV infection. However, there is insufficient data about HIV/AIDS epidemiology in prisons. Our study, conducted in Zambia, a sub-Saharan African nation with an estimated HIV prevalence of 19% in adults, was designed to address this shortfall.

Antimalarial drug sensitivity patterns in the western province of Zambia. Implications for the management of primary health care (PHC)

The management of acute malaria consists of chemotherapy aimed at restoring the normal function of all organs. Appropriate treatment is dependent upon extensive knowledge of the drug sensitivity patterns of the malaria parasites in the area. This is also important for chemoprophylaxis. Drug sensitivity patterns and recrudescence rates for Mongu (Western Province in Zambia) are suggestive of a likely increase in resistance to both chloroquine and sulfadoxine-pyrimethamine (Fansidar). We found RI (19.4%), RII (1.5%) and RIII (4.4%) resistance to chloroquine and RII (4.3%) resistance to Fansidar. This calls for careful consideration of treatment schedules, legislation pertaining to the distribution of drugs in the general public and alternative antimalarial control strategies.