Anthropological insights into the use of race/ethnicity to explore genetic contributions to disparities in health

Anthropological insights into the use of race/ethnicity to explore genetic contributions to disparities in health were developed using in-depth qualitative interviews with editorial staff from nineteen genetics journals, focusing on the methodological and conceptual mechanisms required to make race/ethnicity a genetic variable. As such, these analyses explore how and why race/ethnicity comes to be used in the context of genetic research, set against the background of continuing critiques from anthropology and related human sciences that focus on the social construction, structural correlates and limited genetic validity of racial/ethnic categories. The analyses demonstrate how these critiques have failed to engage geneticists, and how geneticists use a range of essentially cultural devices to protect and separate their use of race/ethnicity as a genetic construct from its use as a societal and social science resource. Given its multidisciplinary, biosocial nature and the cultural gaze of its ethnographic methodologies, anthropology is well placed to explore the cultural separation of science and society, and of natural and social science disciplines. Anthropological insights into the use of race/ethnicity to explore disparities in health suggest that moving beyond genetic explanations of innate difference might benefit from a more even-handed critique of how both the natural and social sciences tend to essentialize selective elements of race/ethnicity. Drawing on the example of HIV/AIDS, this paper demonstrates how public health has been undermined by the use of race/ethnicity as an analytical variable, both as a cipher for innate genetic differences in susceptibility and response to treatment, and in its use to identify 'core groups' at greater risk of becoming infected and infecting others. Clearly, a tendency for biological reductionism can place many biomedical issues beyond the scope of public health interventions, while socio-cultural essentialization has tended to stigmatize 'unhealthy behaviours' and the communities where these are more prevalent.     

Construction of a shuttle vector containing a single O6-methylguanine: a probe for mutagenesis in mammalian cells

A shuttle vector, pKE15, was constructed for investigating the mechanisms by which single carcinogen-DNA adducts induce mutations in mammalian cells. pKE15 contains the SV40 origin of replication, the neomycin resistance gene, SV40 polyadenylation sequences and the pML2 origin of replication. Transfection of pKE15 into CHO cells established the G418-resistant phenotype; the frequency of G418-resistant clones was approximately 10(-4), a value that is similar to those obtained with other SV40-based vectors expressing the neomycin resistance gene. A tetranucleotide containing O6-methylguanine, a DNA adduct formed by carcinogenic alkylating agents, was incorporated into a 4-base gap positioned in the center of a PstI site. The tetranucleotide containing the adduct was physically mapped to a 14-base-pair region of the shuttle vector that included the ligation target, the PstI site. It was incorporated approximately equally into either of the complementary strands of the shuttle vector. The ligation efficiency of the tetranucleotide into the gapped genome was approximately 100% and was independent of the concentration of tetranucleotide used at concentrations ranging over one order of magnitude. The potential applications of the site-specifically modified genome for establishing the mutagenic fate of O6-methylguanine in repair-proficient and -deficient CHO cells are discussed.     

Foraminifera and meiofauna on an intertidal mudflat,Cornwall, England: Populations; respiration and secondary production; and energy budget

A rich and varied meiofauna inhabits a Cornish mudflat near the mouth of the Tamar River in southwestern England. Population densities range from 117 to 943 individuals · g^–1 (wet) sediment (1.4–11.4 × 10⁶ individuals · m^–2), with foraminifera, harpacticoid copepods and nematodes appearing in nearly equal numbers and comprising most of the meiofauna. Seasonally, meiofaunal numbers rise and fall with solar radiation and vary inversely with river discharge. Two species, the atestate allogromiid A and the calcareous Haynesina germanica (Ehrenberg), far outnumber other foraminifera; their population densities and growth rates reach maxima in spring and summer.Monthly rates of sediment respiration are locally variable, but clearly increase from winter (4.13 ml O₂ · m^–2 · h^–1 in December) to spring (38.87 ml O₂ · m^–2 · h^–1 in April). Experiments and calculations ascribe approximately 30% of this total to the meiofauna (including microfauna and microflora), 50% to bacteria and less than 20% to chemical oxidation. A tentative energy budget for the mudflat suggests that secondary production by meiofauna is small as compared with coastal environments elsewhere, and that meiofaunal production (426 Kcal · m^–2 · y^–1) is nearly twice meiofaunal respiration (252 Kcal · m^–2 · yr^–1).     

Mechanistic insight into nuclear receptor‐mediated regulation of bile acid metabolism and lipid homeostasis by grape seed procyanidin extract (GSPE)

Dietary procyanidins have emerged as important bioactive components that regulate various metabolic pathways to maintain homeostasis. Grape seed procyanidin extract (GSPE), in particular, has demonstrated regulatory effects on bile acid and lipid metabolism in vivo. While numerous studies in rodent models have shown the potent hypolipidemic action of grape seed extracts, human studies have shown inconsistent results. This review will focus on the molecular mechanisms underlying the hypolipidemic actions of GSPE identified to date, specifically highlighting the effects exerted via nuclear receptors. Such evidence may provide avenues for future research in human subjects with GSPE as a therapeutic treatment for the prevention and amelioration of the metabolic syndrome and cardiovascular disease.     

The Phylogeography and Spatiotemporal Spread of South-Central Skunk Rabies Virus

The south-central skunk rabies virus (SCSK) is the most broadly distributed terrestrial viral lineage in North America. Skunk rabies has not been efficiently targeted by oral vaccination campaigns and represents a natural system of pathogen invasion, yielding insights to rabies emergence. In the present study we reconstructed spatiotemporal spread of SCSK in the whole territory of its circulation using a combination of Bayesian methods. The analysis based on 241 glycoprotein gene sequences demonstrated that SCSK is much more divergent phylogenetically than was appreciated previously. According to our analyses the SCSK originated in the territory of Texas ~170 years ago, and spread geographically during the following decades. The wavefront velocity in the northward direction was significantly greater than in the eastward and westward directions. Rivers (except the Mississippi River and Rio Grande River) did not constitute significant barriers for epizootic spread, in contrast to deserts and mountains. The mean dispersal rate of skunk rabies was lower than that of the raccoon and fox rabies. Viral lineages circulate in their areas with limited evidence of geographic spread during decades. However, spatiotemporal reconstruction shows that after a long period of stability the dispersal rate and wavefront velocity of SCSK are increasing. Our results indicate that there is a need to develop control measures for SCSK, and suggest how such measure can be implemented most efficiently. Our approach can be extrapolated to other rabies reservoirs and used as a tool for investigation of epizootic patterns and planning interventions towards disease elimination.     

Sleeping blood,tremor and paralysis: A trans-cultural approach to an unusual conversion reaction

An unusual conversion reaction and a related folk belief system are described in a Cape Verdean-American woman. A clinical approach is presented which stresses the need to negotiate between professional and popular explanatory models of illness. It is suggested that a significant factor in the successful management of this patient's symptoms was the acceptance of a mutually-understandable idiom for communication and treatment.