Effects of leaf extracts of Vernonia amygdalina on the force and rate of contractility of an isolated mammalian heart

Background: Vernonia amygdalina is a common medicinal plant that is widely used by local communities and traditional herbalists in central Uganda in management of various conditions including hypertension that occurs as a result of changes in heart contractility. However, there is limited scientific information of V. amygdalina effects on the force and rate of contractility of the heart. The study evaluated the inotropic and chronotropic effect of methanol, aqueous, ether and total crude leaf extracts of V. amygdalina on isolated perfused rabbit heart.Methods: An experimental laboratory based study determined the effects of V. amygdalina extracts on the rate and force of contraction isolated perfused rabbit using the Langendorff’s heart perfusion experiment and methods. The heart rate (beats/minute) was counted per minute. The force of contraction of the heart was determined measuring the height of each peak on the kymogram.Results: The findings showed that the force and rate of heart contractility reduced with increasing doses of methanol, aqueous ether and total crude leaf extracts at doses of 0.5, 8.0, 62.0 and 250.0 mg/ml. The force and rate of heart contractility at a dose of 250.0 mg/ml for all the extracts were comparable to that of acetylcholine drug to almost causing cardiac arrest.Conclusions: The leaf extracts of V. amygdalina contain compounds that reduced the force and rate of contraction of an isolated rabbit heart

Effect of chronic alcohol consumption on the red blood cell count and RBC indices in the HIV infected patients on d4T/3TC/NVP drug regimen in Uganda

Alcohol consumption is common problem in Uganda. Among the types of alcohols consumed include beers, spirits, liqueurs, wines and traditional brew. These alcohols are easily accessible and consumed by many people including the HIV infected patients who are on the d4T/3TC/NVP regimen. The aim of this study was to determine the effect of chronic alcohol intake on the red blood cell count (RBC) and the RBC indices in the HIV-infected patients on d4T/3TC/NVP regimen. It was a case control study that used a repeated measures design model where serial measurements of the red blood cell count (RBC) and RBC indices were determined at 3 month interval for 9 months. A total of 41 HIV infected patients were recruited and grouped into two arms; the control group had 21 patients and the chronic alcohol group had 20 patients. The RBC and RBC indices of the whole blood were determined using automated hematological Coulter CBC-5 Hematology Analyzer system using standard procedures. The data was sorted into alcohol-use self reporting by WHO AUDIT tool and alcohol-use biomarkers groups. It was analysed using the SAS 2003 version 9.1 statistical package with the repeated measures fixed model. The means were compared using the student t-test. The mean MCV and MCH values in the chronic alcohol use group were higher than in the control group and there was a significant difference between the 2 groups (p<0.05) for both the WHO AUDIT tool group and chronic alcohol use biomarkers group. The mean RBC count, Hct, HGB and MCHC values in both the control and chronic alcohol use groups were within the normal reference ranges for both groups though the trend was lower in alcohol group. Chronic alcohol use affects the RBC and RBC indices in the HIV infected patients on d4T/3TC/NVP treatment regimen

Chronic alcohol use affects therapeutic steady state plasma drug concentrations of stavudine, lamivudine and nevirapine in HIV-infected patients during 9 months follow up period: WHO AUDIT tool application G

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