Anti-onchocerca Metabolites from Cyperus articulatus:Isolation,In Vitro Activity and In Silico‘Drug-Likeness’

The aims of this investigation were to isolate active ingredients from the roots/rhizomes of Cyperus articulatus used as herbal medicine in Cameroon for the treatment of human onchocerciasis and to assess the efficacy of the metabolites on the Onchocerca worm.The antifilarial activity was evaluated in vitro on microfilariae(Mfs)and adult worms of the bovine derived Onchocerca ochengi,a close relative of Onchocerca volvulus.Cytotoxicity was assessed in vitro on monkey kidney epithelial cells.The structures of the active compounds were determined using spectroscopic methods and their drug-likeness evaluated using Lipinski parameters.Two secondary metabolites,AMJ1[containing mustakone(1)as the major component]and linoleic acid or(9Z,12Z)-octadeca-9,12-dienoic acid(2)were isolated.Both compounds were found to kill both the microfilariae and adult worms of O.ochengi in a dose dependent manner.The IC50s for AMJ1 were 15.7 lg/mL for Mfs,17.4 lg/mL for adult males and 21.9 lg/mL for adult female worms while for linoleic acid the values were,15.7 lg/mL for Mfs,31.0 lg/mL for adult males and 44.2 lg/mL for adult females.The present report provides the first ever evidence of the anti-Onchocerca efficacy of AMJ1 and linoleic acid.Thus,these secondary metabolites may provide a lead for design and development of new antifilarial agents.

Comparison of the Sensitivities of Different PCR Assays for the Detection of Mycobacterium tuberculosis Complex Isolates from Five Regions of Cameroon

The accurate diagnosis of tuberculosis caused by members of the Mycobacterium tuberculosis complex (MTBC) has remained a major challenge in clinical laboratories world-wide. Several studies have evaluated the use of highly specific in-house PCR assays targeting the IS6110, hupB, rpoB, oxyR, and IS1081 genes in the detection of MTBC species with reports on variable sensitivities depending on the geographical sourcing of isolates. In the present investigations, we evaluated the sensitivities of these PCR assays on 125 MTBC cultured isolates from five (West, Centre, Littoral, North West and South West) of the ten regions of Cameroon. Of this number, 124 (99.2%), 117 (93.6%), 123 (99.1%), 119 (95.2%) and 118 (94.4%) were positive by the IS6110, hupB, rpoB, oxyR, and IS1081-based PCR assays respectively. A total of 110 (88%) of the cultured isolates were also identified as MTBC by standard biochemical tests. Of this number, 109 (99.1%), 104 (94.5%), 109 (99.1%), 106 (96.4%) and 104 (94.5%) were positive in the IS6110, hupB, rpoB, oxyR, and IS1081-based PCR assays respectively. Concordant PCR results were obtained for 108 of the 125 samples. The 15 isolates that were negative biochemically scored sensitivities ranging from 100% (for the IS6110 assay) to 86.7% (for the hupB and oxyR assay). The combination of the IS6110 assay, which turned out to be the most sensitive, and each of the other assays gave 100% sensitivity. We conclude that the combined targeting of the IS6110 and rpoB genes is likely to yield the most sensitive PCR procedure for the diagnosis of MTBC infection in the five regions of Cameroon.

Immuno-haematologic and virologic responses and predictors of virologic failure in HIV-1 infected adults on first-line antiretroviral therapy in Cameroon

Background:Contemporary data on the immunologic,haematologic and virologic responses and predictors of virologic failure after initiation of free antiretroviral treatment in Cameroon are needed to evaluate the current treatment-monitoring algorithm and to complement efforts to scale-up and improve on the management of HIV infections.Methods:This was a cross-sectional study conducted between October 2010 and June 2012.A total of 951 participants aged 18-74 years were recruited from selected approved HIV treatment centres of the Northwest and Southwest regions.This comprised 247 males and 704 females.Demographic,self-reported risk behaviours and socioeconomic data were obtained using a structured questionnaire.Full blood and CD4+T-cell counts were done using standard automated techniques.Determination of viral load(VL)was done using Abbott RealTime HIV-1 m2000™system.Data was analysed using SPSS version 17.The statistical significance level was P<0.05.Results:The median duration of antiretroviral therapy(ART)was 24 months.The population mean CD4+T-cell count was 255.3 cells/μL[95%CI,236.8-273.9].Overall,45.9%,43.8%and 10.2%of the participants had CD4+T-cell counts of<200 cells/μL,200-499 cells/μL and>500 cells/μL respectively.Anaemia was present in 26.2%of the participants with 62.3%,25.7%and 12%described as mild,moderate and severe anaemia respectively.Virologic failure occurred in 23.2%of the participants with 12.3%having VL>10,000 RNA copies/mL.Meanwhile 76.8%of patients attained adequate viral suppression with 40.8%having undetectable viral load.The age group 18-29 years(p=0.024),co-infection with tuberculosis(p=0.014),anaemia(p=0.028)and distance from the treatment centre(p=0.011)independently predicted virologic failure.Conclusion:The majority of the participants achieved adequate viral suppression after≥6 months of ART.Despite these favourable immuno-haematologic and virologic outcomes,the National AIDS Control Program should step-up efforts to improve on antiretroviral drug distribution,as well as proper assessment and management of anaemia,foster early diagnosis and treatment of tuberculosis and enhance treatment adherence counselling especially in younger patients.

Comparison of conventional and non-invasive diagnostic tools for detecting Plasmodium falciparum infection in southwestern Cameroon:a cross-sectional study

Background:Malaria remains a significant health challenge in sub-Saharan Africa,with early diagnosis critical to reducing its morbidity and mortality.Despite the increasing Plasmodium spp.diagnostic capabilities,access to testing is limited in some cases by the almost absolute requirement for blood from potentially infected subjects as the only sample source for all conventional methods.A rapid test on non-invasive specimen with comparable performance to microscopy for the screening or diagnosis of all participants is invaluable.This study sought to compare conventional and non-invasive diagnostic tools for detecting Plasmodium falciparum.