The current global occurrence of dengue infection annually is approximately 400 million, with a case fatality rate of 2.5%. However, there are no antiviral agents. Carica papaya leaf extract is known for its medicinal value, due to the presence of organic compounds that possess antimicrobial, anti-inflammatory, and antioxidant activities. This study determined the anti-dengue effect of C. papaya leaf extract silver synthesized nanoparticles. In this study, aqueous and non-aqueous extractions were carried out, followed by the synthesis of silver nanoparticles as well as characterization through Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy. The in vitro anti-dengue effect was evaluated using a focus reduction neutralization test on kidney Vero E2 cell lines. In silico studies involved molecular docking to determine the potential interactions between the bioactive compounds in C. papaya leaf extract and the viral NS5 protein. C. papaya leaf methanol extract silver synthesized nanoparticle was the most promising with an IC50 of 9.20 µg/mL. Molecular docking showed 5,7 dimethoxycoumarin as the best ligand, with binding energy of −7.75 kcal/mol, indicating high affinity for the NS5 protein. These results highlight that C. papaya leaf methanol extract silver synthesized nanoparticles could be used to inhibit dengue virus type 2 viral replication. However, we recommend further studies to determine their toxicity and the safety profiles.

Euphorbia ingens is traditionally used to treat and manage cancer in Ambeere community of Embu County in Kenya. Whilst research has demonstrated the bioactivities of E. ingens including antimicrobial, antitubercular and antifungal activities, scientific validation of its anticancer properties is limited. This study evaluated the antiproliferative potentials of E. ingens on human prostate cancer cell line (DU-145). The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay was used to assess the antiproliferative activity, chemical constituents were analysed by qualitative colour method and Gas Chromatography-Mass Spectrometry analysis. At the same time, the investigation of putative molecular targets and mechanisms of action of E. ingens was done through network pharmacological analysis. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was carried out to validate the network predictions of putative targets. Our result showed E. ingens ethyl acetate inhibited DU-145 growth (IC50 of 9.71 ± 0.4 µg/ml) with a high selectivity index of 8.26. There was the presence of phenols, terpenoids, flavonoids, tannins, sterols, and saponins; additional 18 compounds were identified by the GC-MS approach. ESR1, IL6, MMP9, CDK2, MAP2K1, AR, PRKCD, CDK1, CDC25B, and JAK2 were indicated as key targets of E. ingens against prostate cancer with the PI3K-AKT, MAPK, and p53 signalling pathways identified as the most probable mechanisms of action. There was significant downregulation of AR and BCL2, and upregulation of p53 and caspase-3 in E. ingens-treated DU-145 cells compared to 0.2 % DMSO negative control. Our results suggest that E. ingens has phytochemical compounds efficacious at inhibiting the proliferation of DU-145 cells; therefore, the plant can be considered a potential source of compounds that may be used to manage and treat prostate cancer; however, further in vivo evaluations are needed.

Soil microbiomes in forest ecosystems act as both nutrient sources and sinks through a range of processes including organic matter decomposition, nutrient cycling, and humic compound incorporation into the soil. Most forest soil microbial diversity studies have been performed in the northern hemisphere, and very little has been done in forests within African continent. This study examined the composition, diversity and distribution of prokaryotes in Kenyan forests top soils using amplicon sequencing of V4-V5 hypervariable region of the 16S rRNA gene. Additionally, soil physicochemical characteristics were measured to identify abiotic drivers of prokaryotic distribution. Different forest soils were found to have statistically distinct microbiome compositions, with Proteobacteria and Crenarchaeota taxa being the most differentially abundant across regions within bacterial and archaeal phyla, respectively. Key bacterial community drivers included pH, Ca, K, Fe, and total N while archaeal diversity was shaped by Na, pH, Ca, total P and total N. To contextualize the prokaryote diversity of Kenyan forest soils on a global scale, the sample set was compared to amplicon data obtained from forest biomes across the globe; displaying them to harbor distinct microbiomes with an over-representation of uncultured taxa such as TK-10 and Ellin6067 genera.

Bedbugs have experienced an extraordinary upsurge in the recent past across the world. This cross-sectional study aimed to explore the community perception of the pest outbreaks, the population dynamics, and dispersal patterns under different habitat systems. A survey was conducted within communities in nine counties in Kenya, where geographical coordinates of the sites of bedbug presence were recorded and maximum entropy distribution modelling (MaxEnt) was used to map and predict the potentially suitable habitat, while system thinking and system dynamics approach with Vensim PLE 8.0.9 software was applied to implement bedbug infestation dynamics. Our results indicated that majority of the respondents had ample knowledge on bedbugs and were concerned about the physico-psychologic and socio-economic health effects. Spatial distribution analysis showed regions in Kenya with optimal to suitable for bedbug occurrence in the whole country, and similar results were found at continental level across Africa. Furthermore, infestation dynamics results showed a rapid mobility of bedbug from one house to another. In terms of management strategies, the models showed that the combination of chemical with other control methods was considerably much more effective compared to the use of chemical approach only, appointing integrated pest management strategy as a better intervention approach in controlling the pest.

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