Evaluation of the Insecticidal Activities of α-Pinene and 3-Carene on Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae).

Pest management in most sub-Saharan subsistence agriculture involves mainly the use of botanicals that are either applied as powders, solvent extracts, ash or essential oils. Two hydrogenated monoterpenes (α-pinene and 3-carene) from Cupressus sempervirens were tested against Sitophilus zeamais in the laboratory to evaluate the contact and fumigation effects on the mortality of adult and immature weevils, progeny production, and grain damage. Contact toxicity of the terpenes was investigated at these concentrations: 0.08, 4, 8 and 12 ppm (terpene/maize), while fumigant action was studied at the following doses: 1, 2, 3, and 4 ppm. The results indicate that insecticidal effects were concentration-dependent since mortality increased with dosage and exposure periods. After a 14-day exposure period at the concentration of 12 ppm of α-pinene and 3-carene/grain, more than 98% mortality of the mature weevils was observed at concentrations of 4.1333 and 1.642 ppm respectively and progeny production was reduced by 98% and 100%, respectively. When α-pinene and 3-carene were applied as fumigants, LC50s (lethal concentrations that generate 50% mortality) of 1.402 and 0.610 ppm were obtained after 24 h of exposure, respectively. At concentrations above 3 ppm, both monoterpenes acted as repellents to weevils and reduced grain damage by 80%. Both monoterpenes inhibited the development of immature stages of the weevil and reduced progeny by up to 94%. These compounds are very promising and effective and could be exploited as novel phytoinsecticides against the maize weevil.

Pre-treatment drug resistance and HIV-1 genetic diversity in the rural and urban settings of Northwest-Cameroon.

BACKGROUND: With the scale-up of antiretroviral therapy (ART), pre-treatment drug resistance (PDR) appears ≥10% amongst ART-initiators in many developing countries, including Cameroon. Northwest region-Cameroon having the second epidemiological burden of HIV infection, generating data on PDR in these geographical settings, will enhance evidence-based decision-making. OBJECTIVES: We sought to ascertain levels of PDR and HIV-1 clade dispersal in rural and urban settings, and their potential association with subtype distribution and CD4-staging. METHODS: A cross-sectional study was conducted from February to May 2017 among patients recently diagnosed with HIV-infection and initiating ART at the Bamenda regional Hospital (urban setting) and the Mbingo Baptist hospital (rural setting). Protease and reverse transcriptase sequencing was performed using an in-house protocol and pre-treatment drug resistance mutations were interpreted using Stanford HIVdb.v8.3. Phylogeny was performed for subtype assignation. RESULTS: A total of 61 patient sequences were generated from ART initiators (median age: 37 years old; 57.4% female; median CD4 cell count: 184 [IQR: 35-387] in urban vs. 161 [IQR: 96-322] cells/mm3 in rural). Overall, the level of PDR was 9.8% (6/61). Of note, burden of PDR was almost doubled in urban (12.9% [4/31]) compared to rural setting 6.7% (2/30), p = 0.352). Fifteen (15) PDR mutations were found among four patients the urban settings [6 resistance mutations to NRTIs:[M41L (2), E44D (1), K65R (1), K70E (1), M184V/I (2), K219R (1)] and 6 resistance mutations to NNRTIs: K103N (1), E138A/G (2), V179E (1), M230L (1), K238T (1), P225H (1)] against two (02) mutations found in two patients in the rural setting[2 resistant mutations to NNRTIs: E138A (1) and Y188H (1)]. The rural setting showed more genetic diversity (8 subtypes) than the urban setting (5 subtypes), with CRF02_AG being the most prevalent clade (72.1% [44/61]). Of note, level of PDR was similar between patients infected with CRF02_AG and non-CRF02_AG infected (9.1% [4/44]) vs. 11.8% [2/17]), p = 1.000). Moreover, PDR appeared higher in patients with CD4 cell count <200 cells/mm3 compared to those with CD4 cell count ≥200 cells/mm3 (14.7% [5/34]) vs. 3.7% [1/27]), p = 0.214). CONCLUSIONS: PDR is at a moderate rate in the Northwest region of Cameroon, with higher burden within urban populations. CRF02_AG is the most predominant clade in both urban and rural settings. No effect of HIV molecular epidemiology and CD4-staging on the presence of PDR in patients living in these settings was found. Our findings suggest close monitoring, NNRTI-sparing regimens or sequencing for patients initiating ART, especially in urban settings.

Next-generation sequencing provides an added value in determining drug resistance and viral tropism in Cameroonian HIV-1 vertically infected children.

With limited and low-genetic barrier drugs used for the prevention of mother-to-child transmission (PMTCT) of HIV in sub-Saharan Africa, vertically transmitted HIV-1 drug-resistance (HIVDR) is concerning and might prompt optimal pediatric strategies.The aim of this study was to ascertain HIVDR and viral-tropism in majority and minority populations among Cameroonian vertically infected children.A comparative analysis among 18 HIV-infected children (7 from PMTCT-exposed mothers and 11 from mothers without PMTCT-exposure) was performed. HIVDR and HIV-1 co-receptor usage was evaluated by analyzing sequences obtained by both Sanger sequencing and ultra-deep 454-pyrosequencing (UDPS), set at 1% threshold.Overall, median (interquartile range) age, viremia, and CD4 count were 6 (4-10) years, 5.5 (4.9-6.0) log10 copies/mL, and 526 (282-645) cells/mm, respectively. All children had wild-type viruses through both Sanger sequencing and UDPS, except for 1 PMTCT-exposed infant harboring minority K103N (8.31%), born to a mother exposed to AZT+3TC+NVP. X4-tropic viruses were found in 5 of 15 (33.3%) children (including 2 cases detected only by UDPS). Rate of X4-tropic viruses was 0% (0/6) below 5 years (also as minority species), and became relatively high above 5 years (55.6% [5/9], P = .040. X4-tropic viruses were higher with CD4 ≤15% (4/9 [44.4%]) versus CD4 >15% (1/6 [16.7%], P = .580); similarly for CD4 ≤200 (3/4 [75%]) versus CD4 >200 (2/11 [18.2%] cells/mm, P = .077.NGS has the ability of excluding NRTI- and NNRTI-mutations as minority species in all but 1 children, thus supporting the safe use of these drug-classes in those without such mutations, henceforth sparing ritonavir-boosted protease inhibitors or integrase inhibitors for the few remaining cases. In children under five years, X4-tropic variants would be rare, suggesting vertical-transmission with CCR5-tropic viruses and possible maraviroc usage at younger ages.

The development of an in vitro screening strategy for topically applied products.

The objective of this study was the pharmaco-toxicological understanding of the constituents of an authenticated herbal mixture. The mixture was prepared by maceration in ethanol and subsequent dilution to produce a topically applied lotion, for which the intended target conditions are psoriasis and eczema. A three-tiered in vitro screening strategy was adopted for evaluating this product, comprising cytotoxicity assays; mutagenicity screening and therapeutic evaluation. Viability assays performed with dilutions of both the herbal concentrate and final product on organotypic cell lines indicated that neither preparation acted as an irritant. Genotoxicity screening using six strains of Salmonella typhimurium showed no mutagenic potential, and furthermore significant anti-microbial activity was evident. Therapeutic evaluation involved assessing the antioxidant potential of the extract, which can be correlated to an anti-inflammatory effect. Nitroblue-tetrazolium (NBT) assay results indicate that the extract can reduce superoxide anion generation by 45%. The extract also increased cell viability on exposure to hydrogen peroxide by 28%, illustrating its dismutation potential. A 3-D skin culture system, EpiDerm, released 3000 microg/ml upon exposure to the extract, implying that the components enhance arachidonic acid metabolism. Overall, it may be concluded that the herbal extract is sufficiently non-toxic for dermal application and possesses anti-inflammatory activity.

Synthesis of some p-toluenesulfonyl-hydrazinothiazoles and hydrazino-bis-thiazoles and their anticancer activity.

A series of novel p-toluenesulfonyl-hydrazinothiazoles and hydrazino-bis-thiazoles derivatives (2a-f, 3a-f and 5-8) were synthesized by initial condensation of p-toluenesulfonylthiosemicarbazide 1 with a series of α-halogenocarbonyls in acetone or dimethylformamide (DMF)/acetone, mixture. All our synthesized compounds were submitted for further acylation reaction in the presence of acetic anhydride. The structures of newly synthesized derivatives 2a-f, 3a-f and 5-8 were confirmed by IR, (1)H-NMR, EIMS spectral data and elemental analysis. Compounds 2a, 2c, 2d, 2e and 3a showed significant anticancer activities (IC(50)<10 µM) on both prostate DU-145 and hepatocarcinoma Hep-G2 cancer cell lines.