Specialized insect herbivores commonly co‐opt plant defences for protection against predators, but the costs, benefits and mechanisms of sequestration are poorly understood. We quantified sequestration of toxic cardenolides by the specialist aphid Aphis nerii when reared on four closely related milkweed (Asclepias) species with >20‐fold variation in cardenolide content, and in the presence or absence of generalist ladybug predators. Increasing concentrations of apolar plant cardenolides increased sequestered amounts in aphids. High concentrations in plants impaired aphid population growth, but also reduced the top‐down effects of predators. An in vitro enzymatic assay of total cardenolides in aphid bodies using the cardenolides’ target (animal Na+/K+‐ATPase) revealed that the subset of sequestered cardenolides is disproportionally more toxic than cardenolides in leaves. All aphids accumulated two cardenolides not present in their host plant, even on plants with very low foliar cardenolide concentrations. Sequestration of potent cardenolides by A. nerii thus involves passive, concentration‐dependent uptake from the host plant, as well as a presumably more active mechanism of modification and up‐concentration of plant cardenolides. The concentration of toxins in the host plant thus not only determines the negative impacts on growth and performance of an aphid, but also the ease and efficiency by which toxins are sequestered for the aphid’s defence, making the costs and benefits of plant toxins highly context‐dependent for both the plant and the herbivore. Therefore, variation in plant toxins is of central importance for co‐evolutionary plant–insect interactions, particularly in environments with variable predator pressure. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13144/suppinfo is available for this article.

Background and Objectives: A majority of medical students believe that treating sexual concerns is important for their careers. However, a minority feel that they have received adequate instruction in medical school. This novel supplemental reproductive and sexual health curriculum at a large academic medical center aimed to address this gap and to improve attitudes, comfort, and knowledge about sexual and reproductive health topics among learners.Methods: Students participated in a series of sexual and reproductive health workshops taught by interdisciplinary health care workers, with the first cohort in a classroom setting and the second cohort using a virtual format due to the COVID-19 pandemic. We administered a novel pre- and postcourse survey to assess attitudes, comfort, and knowledge about the topics. We performed unpaired 1-tailed t tests and χ2 tests to compare the scores on the pre- and postcourse surveys. Results: Sample size was 12 students for the first cohort and 23 students for the second cohort. Reported levels of comfort with taking sexual histories in different age groups and discussing reproductive and sexual health topics increased significantly: 0.92 for the classroom setting, and 0.50 for the virtual setting, with an average increase of 0.65 points on a 4-point Likert scale. There were no significant changes in student attitudes toward or knowledge of reproductive and sexual health.Conclusion: This course elaborated on topics to which medical students traditionally lack adequate exposure, with significant improvement in comfort counseling patients. A disparity between the classroom and virtual setting suggests limitations of online learning for these topics.

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Introduction: Limited data exist on prenatal depression in in high HIV burden resource‐poor settings. Population: 403 pregnant clinic attendees at Gulu Hospital, Uganda. HIV (+) women were oversampled in a ratio of 1 HIV (+): 2 HIV (‐). Methods. Depression was assessed using the Center for Epidemiological Studies‐Depression (CESD) scale. Maternal food insecurity (FI) was evaluated using an individually focused Food Insecurity Access Scale, anemia using a Hemocue® hemoglobinometer, and social support using the 10 item version of the Duke‐UNC functional social support instrument. We performed bivariate and multivariate analyses to identify variables associated with CESD scores keeping those with p <0.05 as well as theoretically or contextually important variables in the final model. Results: CESD scores ranged from 0‐57 (mean 20 + 13.2SD). 62.3% of study women had a major depressive episode (CESD score 蠅15). While being HIV (+) was linked to higher CESD scores in bivariate analyses, in multivariate linear regression maternal food insecurity (β=+0.663) and age (β=+0.227) were the only factors associated with higher CESD scores. Maternal social support (β=‐1.209) and higher hemoglobin (β=‐0.927) were linked to lower CESD scores. Conclusion: Interventions targeting depressed pregnant Ugandan women should better understand how age, food insecurity, anemia, and social support influence prenatal depression. Grant Funding Source: Supported by USAID Feed the Future grant to Tufts University