Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.

There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions

An Analysis of a Ring Attractor Model for Cue Integration

Animals and robots must constantly combine multiple streams of noisy information from their senses to guide their actions. Recently, it has been proposed that animals may combine cues optimally using a ring attractor neural network architecture inspired by the head direction system of rats augmented with a dynamic re-weighting mechanism. In this work we report that an older and simpler ring attractor network architecture, requiring no re-weighting property combines cues according to their certainty for moderate cue conflicts but converges on the most certain cue for larger conflicts. These results are consistent with observations in animal experiments that show sub-optimal cue integration and switching from cue integration to cue selection strategies. This work therefore demonstrates an alternative architecture for those seeking neural correlates of sensory integration in animals. In addition, performance is shown robust to noise and miniaturization and thus provides an efficient solution for artificial systems

Genomic Runs of Homozygosity Record Population History and Consanguinity

The human genome is characterised by many runs of homozygous genotypes, where identical haplotypes were inherited from each parent. The length of each run is determined partly by the number of generations since the common ancestor: offspring of cousin marriages have long runs of homozygosity (ROH), while the numerous shorter tracts relate to shared ancestry tens and hundreds of generations ago. Human populations have experienced a wide range of demographic histories and hold diverse cultural attitudes to consanguinity. In a global population dataset, genome-wide analysis of long and shorter ROH allows categorisation of the mainly indigenous populations sampled here into four major groups in which the majority of the population are inferred to have: (a) recent parental relatedness (south and west Asians); (b) shared parental ancestry arising hundreds to thousands of years ago through long term isolation and restricted effective population size (N(e)), but little recent inbreeding (Oceanians); (c) both ancient and recent parental relatedness (Native Americans); and (d) only the background level of shared ancestry relating to continental N(e) (predominantly urban Europeans and East Asians; lowest of all in sub-Saharan African agriculturalists), and the occasional cryptically inbred individual. Moreover, individuals can be positioned along axes representing this demographic historic space. Long runs of homozygosity are therefore a globally widespread and under-appreciated characteristic of our genomes, which record past consanguinity and population isolation and provide a distinctive record of the demographic history of an individual's ancestors. Individual ROH measures will also allow quantification of the disease risk arising from polygenic recessive effects

Do aluminium-based phosphate binders continue to have a role in contemporary nephrology practice?

Background: Aluminium-containing phosphate binders have long been used for treatment of hyperphosphatemia in dialysis patients. Their safety became controversial in the early 1980's after reports of aluminium related neurological and bone disease began to appear. Available historical evidence however, suggests that neurological toxicity may have primarily been caused by excessive exposure to aluminium in dialysis fluid, rather than aluminium-containing oral phosphate binders. Limited evidence suggests that aluminium bone disease may also be on the decline in the era of aluminium removal from dialysis fluid, even with continued use of aluminium binders

Propagation of Respiratory Aerosols by the Vuvuzela

Vuvuzelas, the plastic blowing horns used by sports fans, recently achieved international recognition during the FIFA World Cup soccer tournament in South Africa. We hypothesised that vuvuzelas might facilitate the generation and dissemination of respiratory aerosols. To investigate the quantity and size of aerosols emitted when the instrument is played, eight healthy volunteers were asked to blow a vuvuzela. For each individual the concentration of particles in expelled air was measured using a six channel laser particle counter and the duration of blowing and velocity of air leaving the vuvuzela were recorded. To allow comparison with other activities undertaken at sports events each individual was also asked to shout and the measurements were repeated while using a paper cone to confine the exhaled air. Triplicate measurements were taken for each individual. The mean peak particle counts were 658×103 per litre for the vuvuzela and 3.7×103 per litre for shouting, representing a mean log10 difference of 2.20 (95% CI: 2.03,2.36; p<0.001). The majority (>97%) of particles captured from either the vuvuzela or shouting were between 0.5 and 5 microns in diameter. Mean peak airflows recorded for the vuvuzela and shouting were 6.1 and 1.8 litres per second respectively. We conclude that plastic blowing horns (vuvuzelas) have the capacity to propel extremely large numbers of aerosols into the atmosphere of a size able to penetrate the lower lung. Some respiratory pathogens are spread via contaminated aerosols emitted by infected persons. Further investigation is required to assess the potential of the vuvuzela to contribute to the transmission of aerosol borne diseases. We recommend, as a precautionary measure, that people with respiratory infections should be advised not to blow their vuvuzela in enclosed spaces and where there is a risk of infecting others

Origin of an Alternative Genetic Code in the Extremely Small and GC–Rich Genome of a Bacterial Symbiont

The genetic code relates nucleotide sequence to amino acid sequence and is shared across all organisms, with the rare exceptions of lineages in which one or a few codons have acquired novel assignments. Recoding of UGA from stop to tryptophan has evolved independently in certain reduced bacterial genomes, including those of the mycoplasmas and some mitochondria. Small genomes typically exhibit low guanine plus cytosine (GC) content, and this bias in base composition has been proposed to drive UGA Stop to Tryptophan (Stop→Trp) recoding. Using a combination of genome sequencing and high-throughput proteomics, we show that an α-Proteobacterial symbiont of cicadas has the unprecedented combination of an extremely small genome (144 kb), a GC–biased base composition (58.4%), and a coding reassignment of UGA Stop→Trp. Although it is not clear why this tiny genome lacks the low GC content typical of other small bacterial genomes, these observations support a role of genome reduction rather than base composition as a driver of codon reassignment

Statin Use and the Presence of Microalbuminuria. Results from the ERICABEL Trial: A Non-Interventional Epidemiological Cohort Study

BACKGROUND: Microalbuminuria (MAU) is considered as a predictor or marker of cardiovascular and renal events. Statins are widely prescribed to reduce cardiovascular risk and to slow down progression of kidney disease. But statins may also generate tubular MAU. The current observational study evaluated the impact of statin use on the interpretation of MAU as a predictor or marker of cardiovascular or renal disease. METHODOLOGY/PRINCIPAL FINDINGS: We used cross-sectional data of ERICABEL, a cohort with 1,076 hypertensive patients. MAU was defined as albuminuria ≥20 mg/l. A propensity score was created to correct for "bias by indication" to receive a statin. As expected, subjects using statins vs. no statins had more cardiovascular risk factors, pointing to bias by indication. Statin users were more likely to have MAU (OR: 2.01, 95%CI: 1.34-3.01). The association between statin use and MAU remained significant after adjusting for the propensity to receive a statin based on cardiovascular risk factors (OR: 1.82, 95%CI: 1.14-2.91). Next to statin use, only diabetes (OR: 1.92, 95%CI: 1.00-3.66) and smoking (OR: 1.49, 95%CI: 0.99-2.26) were associated with MAU. CONCLUSIONS: Use of statins is independently associated with MAU, even after adjusting for bias by indication to receive a statin. In the hypothesis that this MAU is of tubular origin, statin use can result in incorrect labeling of subjects as having a predictor or marker of cardiovascular or renal risk. In addition, statin use affected the association of established cardiovascular risk factors with MAU, blurring the interpretation of multivariable analyses