An ethics of anthropology-informed community engagement with COVID-19 clinical trials in Africa

The COVID-19 pandemic has reinforced the critical role of ethics and community engagement in designing and conducting clinical research during infectious disease outbreaks where no vaccine or treatment already exists. In reviewing current practices across Africa, we distinguish between three distinct roles for community engagement in clinical research that are often conflated: 1) the importance of community engagement for identifying and honouring cultural sensitivities; 2) the importance of recognising the socio-political context in which the research is proposed; and 3) the importance of understanding what is in the interest of communities recruited to research according to their own views and values. By making these distinctions, we show that current practice of clinical research could draw on anthropology in ways which are sometimes unnecessary to solicit local cultural values, overlook the importance of socio-political contexts and wider societal structures within which it works, potentially serving to reinforce unjust political or social regimes, and threaten to cast doubt on the trustworthiness of the research. We argue that more discerning anthropological engagement as well as wider collaboration with other social scientists and those working in the humanities is urgently needed to improve the ethics of current biomedical and pharmaceutical research practice in Africa.     

Characterization of plant phenotypes associated with loss-of-function of AtCNGC1, a plant cyclic nucleotide gated cation channel.

Of the 57 cation channel genes in the Arabidopsis genome, over a third encode cyclic nucleotide gated cation channels (CNGCs). CNGCs are ion channels regulated by cytosolic signaling molecules (cyclic nucleotides, calmodulin, and Ca(2+)), and which conduct Ca(2+) as well as K(+) and in some cases Na(+). Little is currently known about the role CNGCs may play in plant growth and development. Here, we examined the hypothesis that an Arabidopsis thaliana genotype containing a null mutation in one of the CGNC genes (AtCNGC1) would display cation uptake-related growth phenotype differences from wild type (WT) plants. We determined that AtCNGC1 protein is primarily expressed in the roots of Arabidopsis seedlings. Seedlings lacking this protein had slightly (6-22%) lower shoot Ca(2+) than WT plants. Primary roots of Atcngc1 mutant seedlings grew faster than roots of WT plants, and had larger angles of gravicurvature and less nitric oxide generation upon gravistimulation. We conclude that channels formed (at least in part) by AtCNGC1 contribute (along with other channels) to Ca(2+) uptake into plants, and that Ca(2+) uptake into roots through AtCNGC1 affects some aspects of growth in the primary root of Arabidopsis seedlings.     

Recalcitrant Grain Legume Vigna radiata, Mung Bean, Made to Regenerate on Change of Hormonal and Cultural Conditions

Induction of shoots is possible from cotyledonary node of Vigna radiata seedlings by culturing them on a low concentration of thidiazuron (TDZ 1.0 μM). Interestingly, flooding the seedlings with the same concentration of TDZ considerably enhanced this effect and also led to the induction of shoots from the epicotyl – an unexpected and significant finding. Even plain mineral medium evoked this response on flooding. But seedlings raised on TDZ and flooding with mineral medium was not so effective. Instead seedlings raised on TDZ (1.0 μM) medium as well as flooding with it had synergistic effect. In a comparative study TDZ (1.0 μM) was found to be more effective than BAP (10 μM). Marked repression of root formation and expansion of shoot–apex were noted in seedlings raised on TDZ or BAP, particularly in cultures that were flooded.     

Promotive effect of polyvinylpolypyrrolidone on pollen embryogenesis in Datura innoxia

Pollen embryos of Datura innoxia Mill are produced in larger numbers from anthers on agar-gelled medium containing polyvinylpolypyrrolidone than on control. The best response is observed with 0.5% polyvinylpolypyrrolidone. The effect is possibly due to adsorption of substances (phenolics) emanating from cultured anthers and inhibiting the development of pollen grains into embryos.     

Interaction of molecular probes with living cells and tissues. Part 2

Summary Cultured rat fibroblasts were exposed to 41 cationic fluorescent probes of very varied hydrophilicity/lipophilicity. Outcome of probe-cell interaction fell into one of the following categories: probe failed to enter the cells; probe accumulated on cell surfaces; probe accumulated in mitochondria, and/or in other intracellular regions. The observations were analysed using a Simplistic Chinese Box (SCB) approach, and the following conclusions were reached. It was the hydrophilic probes which failed to enter cells, whilst extremely lipophilic probes were retained on the cell surfaces. Only the slightly lipophilic cationic probes were permeant, and accumulated in mitochondria. Using the probes log P values to model hydrophilicity/lipophilicity, effective cationic mitochondrial stains can be specified numerically so: 0P _probe<+5. This SCB model was used to rationalise a variety of earlier observations on the action of mitochondrial probes. The applicability of the SCB approach to integrate image-based and biochemical investigations was demonstrated by using the action of chlorpromazine on mitochondrial action as a case example.