ABSTRACT
Background: Medicinal herbs have long been used in the treatment of malaria in the endemic tropical and subtropical regions of the world, especially in sub-Saharan Africa where malaria has remained as a top killer disease to children under five years and expectant mothers. Among the herbs commonly used in Uganda to treat malaria is Zanthoxylum chalybeum (ZC) root-bark and to a lesser extent its leaves. However, the continued use of the root-bark has led to plant extinction due to the destructive method of harvesting the herb as opposed to the leaves. Aim: The study investigated the antiplasmodial activity of the crude ether and methanol leaf extracts of ZC with chloroquine diphosphate as a positive control. Materials and Methods: The in vitro Micro-Test (MARK III) kit was used to determine the antiplasmodial activity of Z. chalybeum Engl. ether and methanol extracts. The effective concentration that caused a 50% P. falciparum schizonts suppression (EC50) values were determined. The antiplasmodial activities of the ether and methanol extracts were expressed as 50% effective concentration (EC50) that was determined from doseresponse curve by non-linear regression analysis (curve-fit) using GraphPad Prism (version 6) software at 95% confidence intervals. Results: The results showed that ether extract of ZC had EC50 value of 13.39 (95% CI: 10.82 – 16.59) μg/ml and methanol extract had EC50 value of 8.10 (95% CI: 5.89 – 11.12) μg/ml. The chloroquine diphosphate, standard had EC50 value of 25.33 (95% CI: 17.07 – 37.60) μg/ml. Conclusion: The ether and methanol extracts of Z. chalybeum Engl. contains compounds that caused Plasmodium falciparum schizonts suppression at a lower concentration, hence the continued use of the herb by the traditional herbalist and local communities in Uganda, in the treatment of malaria.
ABSTRACT
Chronic alcohol consumption is a common problem among the HIV-infected patients on HAART. The study determined the effect of chronic alcohol use on steady state plasma drug concentrations of stavudine (d4T), lamivudine (3TC) and nevirapine (NVP) in HIV-infected patients during the 9 months follow up period. It also determined whether there were some patients with undetectable plasma drug concentrations in their plasma during the follow up. A case control using repeated measures design with serial measurements model, where plasma drug concentrations were measured at 3 month intervals was used. Chronic alcohol-use using WHO AUDIT tool was used to screen patients. A total of 41 patients (21 alcohol group and 20 control group) were followed up for 9 months with blood sampling done at 3 month intervals. The Shimadzu Class-VPTM HPLC Chromatography data system version 6.1 equipment with UV detector was used to measure the plasma drug concentrations. Data was analyzed using SAS 2003 version 9.1 statistical package with repeated measures fixed the model and means were compared using the student t-test. The mean steady state plasma concentration of both d4T and 3TC in chronic alcohol use group were lower than in the control group all throughout the 9 months period of follow-up. The mean steady state plasma drug concentrations of NVP were higher in the alcohol group at 0 and 3 months and lower in the 6 and 9 months as compared to the control group. The mean total plasma NVP concentration was higher in the chronic alcohol group as compared to the control group and the difference was statistically significant (p≤0.05). However some patients had undetectable plasma drug concentrations despite of having ≥ 95 % adherence rate. Chronic alcohol use by the HIV-infected patients lowers the steady state plasma drug concentrations of d4T, 3TC and NVP in patients.