Laxative activities of Mareya micrantha (Benth.) Müll. Arg. (Euphorbiaceae) leaf aqueous extract in rats

<p>Abstract</p> <p>Background</p> <p><it>Mareya micrantha </it>(Benth.) Müll. Arg. (Euphorbiaceae) is a shrub that is commonly used in Côte d'Ivoire (West Africa) for the treatment of constipation and as an ocytocic drug. The present study was carried out to investigate the laxative activity of <it>Mareya micrantha </it>in albino's Wistar rats.</p> <p>Methods</p> <p>Rats were divided in 5 groups of 5 animals each, first group as control, second group served as standard (sodium picosulfate) while group 3, 4 and 5 were treated with leaf aqueous extract of <it>Mareya micrantha </it>at doses of 100, 200 and 400 mg/kg body weight (b.w.), <it>per os </it>respectively. The laxative activity was determined based on the weight of the faeces matter. The effects of the leaves aqueous extract of <it>Mareya micrantha </it>and castor oil were also evaluated on intestinal transit, intestinal fluid accumulation and ions secretion.</p> <p>Results</p> <p>Phytochemicals screening of the extract revealed the presence of flavonoids, alkaloids, tannins, polyphenols, sterols and polyterpenes. The aqueous extract of <it>Mareya micrantha </it>applied orally (100, 200 and 400 mg/kg; <it>p.o</it>.), produced significant laxative activity and reduced loperamide induced constipation in dose dependant manner. The effect of the extract at 200 and 400 mg/kg (<it>p.o</it>.) was similar to that of reference drug sodium picosulfate (5 mg/kg, <it>p.o</it>). The same doses of the extract (200 and 400 mg/kg, <it>p.o</it>.) produced a significant increase (p < 0.01) of intestinal transit in comparison with castor oil (2 mL) (p < 0.01). Moreover, the extract induced a significant enteropooling and excretion of Cl^-, Na⁺, K⁺and Ca²⁺in the intestinal fluid (p < 0.01).</p> <p>Conclusions</p> <p>The results showed that the aqueous extract of <it>Mareya micrantha </it>has a significant laxative activity and supports its traditional use in herbal medicine.</p

Biologically active bisbenzylisoquinoline alkaloids from the root bark of Epinetrum villosum

Methanol and water extracts of the root of Epinetrum villosum (Exell) Troupin (Menispermaceae) were found to exhibit antimicrobial and antiplasmodial activities. Investigation of the active methanol fraction led to the isolation of four bisbenzylisoquinoline alkaloids, i.e., cycleanine, cycleanine N-oxide, isochondodendrine and cocsoline. Structures were established by spectroscopic methods. Cocsoline displayed antibacterial and antifungal activities (MIC values of 1000-15.62 and 31.25 mu g/ml, respectively). Isochondodendrine was found to have the most potent antiplasmodial activity (IC50 = 0- 10 mu g/ml), whereas the IC50 on HCT-116 human colon carcinoma cells was 17.5 mu g/ml (selectivity index 175). Cycleanine acted against HIV-2 (EC50 = 1.83 mu g/ml) but was at least 10-fold less active against HIV-1. Cycleanine N-oxide showed no activity towards all tested microorganisms. (C) 2005 Elsevier Ireland Ltd. All rights reserved

Hepatitis C virus among blood donors in Lubumbashi, DRC: Seroprevalence and molecular characterisation.

To date, no study has been done yet on the distribution of Hepatitis C virus genotypes in Lubumbashi, Democratic Republic of Congo. The objective of this work was to determine the seroprevalence and study the distribution of hepatitis C virus (HCV) genotypes among blood donors in Lubumbashi, DRC. This was a cross-sectional descriptive study among blood donors. The detection of anti-HCV antibodies was carried out by rapid diagnostic test (RDT) then confirmed by Chemiluminescent immuno-assay (CLIA). Viral load was determined by Nucleic Acid Amplification test (NAT) on Panther system and genotyping by Next Generation Sequencing (NGS) on Sentosa platform. The obtained seroprevalence was 4.8%. Genotypes 3a (5.0%), 4 (90.0%) and 7 (5.0%) and a few drug resistance mutations were identified in the study population. Significant disturbances of some studied biochemical parameters (HDL-cholesterol, direct bilirubin, transaminases, ALP, GGT and albumin) have been observed in positive HCV blood donors. Irregular family and volunteer donors have been found as the socio-demographic characteristics associated with hepatitis C. With a seroprevalence of 4.8% obtained among blood donors, Lubumbashi is in an area with medium endemicity for HCV, highlighting the need to implement strategies aiming to improve transfusion safety among blood recipients in Lubumbashi. This study reports for the first time the presence of HCV strains of genotypes 3a, 4 and 7. These results might allow better therapeutic management of HCV infections and contribute to the development of the mapping of HCV genotypes in Lubumbashi and DRC as well

Knowledge, attitude, and practice towards hepatitis B and C viruses among the population of Lubumbashi, Democratic Republic of Congo

Hepatitis B (HBV) and C (HCV) infection remains significant public health problemworldwide. Unfortunately, the Democratic Republic of Congo is in an area of high endemicity, and its population remains poorly informed about these viral infections. Therefore, this study aims to determine Lubumbashi's knowledge, attitudes, and practices toward HBV and HCV

Newer insights into the mechanism of action of <it>Psidium guajava </it>L. leaves in infectious diarrhoea

<p>Abstract</p> <p>Background</p> <p><it>Psidium guajava </it>L., Myrtaceae, is used widely in traditional medicine for the treatment of diarrhoea, dysentery, gastroenteritis, stomachaches, and indigestion. However, the effect of the leaf extract of <it>P. guajava </it>on the pathogenesis of infectious diarrhoea has not been studied. The present study evaluates the effect of a hot aqueous extract (decoction) of dried leaves of <it>P. guajava </it>on parameters associated with pathogenicity of infectious diarrhoea. The aim was to understand its possible mechanism(s) of action in controlling infectious diarrhoea and compare it with quercetin, one of the most reported active constituents of <it>P. guajava </it>with antidiarrhoeal activity.</p> <p>Methods</p> <p>The crude decoction and quercetin were studied for their antibacterial activity and effect on virulence features of common diarrhoeal pathogens viz. colonization of epithelial cells and production and action of enterotoxins. Colonization as measured by adherence of enteropathogenic <it>Escherichia coli </it>(EPEC) and invasion of enteroinvasive <it>E. coli </it>(EIEC) and <it>Shigella flexneri </it>was assessed using HEp-2 cell line. The production of <it>E. coli </it>heat labile toxin (LT) and cholera toxin (CT) and their binding to ganglioside monosialic acid (GM1) were studied by GM1-ELISA whereas the production and action of <it>E. coli </it>heat stable toxin (ST) was assessed by suckling mouse assay.</p> <p>Results</p> <p>The decoction of <it>P. guajava </it>showed antibacterial activity towards <it>S. flexneri </it>and <it>Vibrio cholerae</it>. It decreased production of both LT and CT and their binding to GM1. However, it had no effect on production and action of ST. The decoction also inhibited the adherence of EPEC and invasion by both EIEC and <it>S. flexneri </it>to HEp-2 cells. Quercetin, on the other hand, had no antibacterial activity at the concentrations used nor did it affect any of the enterotoxins. Although it did not affect adherence of EPEC, it inhibited the invasion of both EIEC and <it>S. flexneri </it>to HEp-2 cells.</p> <p>Conclusion</p> <p>Collectively, the results indicate that the decoction of <it>P. guajava </it>leaves is an effective antidiarrhoeal agent and that the entire spectrum of its antidiarrhoeal activity is not due to quercetin alone.</p