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There is an increased need for improved and affordable insect repellents to reduce transmission of rapidly spreading diseases with high mortality rates. Natural products are often used when DEET cannot be afforded or accessed and when consumers choose not to use a synthetic repellent. The essential oils from two newly bred Nepeta cataria (catnip) plants representing two different chemotypes and their respective isolated nepetalactone isomers were evaluated as mosquito repellents against Aedes aegypti mosquitoes that transmit the Zika and Dengue virus in a one choice landing rate inhibition assay. A dose response curve was generated for each treatment and a time course analysis of repellency was performed over 24 hours with a N. cataria essential oil sample. The results indicate that all essential oil samples and their respective purified nepetalactone isomers were able to achieve greater than 95% repellency. Between two and four hours, the ability to repel more than 95% of the mosquitoes diminished. At the lowest concentrations tested, the nepetalactones and crude essential oil samples were more effective than DEET at reducing the number of mosquito landings.

While polyphenolic compounds have many health benefits, the potential development of polyphenols for the prevention/treatment of neurological disorders is largely hindered by their complexity as well as by limited knowledge regarding their bioavailability, metabolism, and bioactivity, especially in the brain. We recently demonstrated that dietary supplementation with a specific grape-derived polyphenolic preparation (GP) significantly improves cognitive function in a mouse model of Alzheimer's disease (AD). GP is comprised of the proanthocyanidin (PAC) catechin and epicatechin in monomeric (Mo), oligomeric, and polymeric forms. In this study, we report that following oral administration of the independent GP forms, only Mo is able to improve cognitive function and only Mo metabolites can selectively reach and accumulate in the brain at a concentration of ∼400 nM. Most importantly, we report for the first time that a biosynthetic epicatechin metabolite, 3'-O-methyl-epicatechin-5-O-β-glucuronide (3'-O-Me-EC-Gluc), one of the PAC metabolites identified in the brain following Mo treatment, promotes basal synaptic transmission and long-term potentiation at physiologically relevant concentrations in hippocampus slices through mechanisms associated with cAMP response element binding protein (CREB) signaling. Our studies suggest that select brain-targeted PAC metabolites benefit cognition by improving synaptic plasticity in the brain, and provide impetus to develop 3'-O-Me-EC-Gluc and other brain-targeted PAC metabolites to promote learning and memory in AD and other forms of dementia.

Growing African Indigenous Vegetables (AIVs) is an innovative way to address poverty and malnutrition problems in Zambia. Farmers' bargaining power plays an important role in increasing AIV production and farmers' income. Based on 300 responses from Zambian AIV farmers, we defined AIV farmers' bargaining power and analyzed its benefits to farmers and the AIV industry. We used the ordered logistic regression model (OLRM) to analyze the influence of several factors that contribute to farmers' bargaining power, and then used the interpretative structural modeling (ISM) to analyze the relationship and hierarchical structure between the effects. Four key results and innovations arose from the analysis of the data. First, we defined farmers' bargaining power through their self-reported bargaining power. Second, we found that the respondents' bargaining power was significantly influenced by seven variables: age, gender, education, main trading partners, awareness of AIV prices, and distance to the market from the farm. Third, the main trading partners and awareness of AIV prices are surface direct factors, gender, education and distance to the market from the farm are middle indirect relationships, and age, belong to any community are deep root factors. Last, farmers' bargaining power can be improved through education, especially women's education level, strengthening farmers' organization construction, altering some of the farmers' trading methods, and developing infrastructure. Overall, we found that bargaining power has played an important role in obtaining higher prices, getting faster payment, getting more income from AIV sales, and expanding AIV planting areas for farmers. [ABSTRACT FROM AUTHOR]