Impregnated netting slows infestation by Triatoma infestans

We used sentinel animal enclosures to measure the rate of infestation by the Chagas disease vector, Triatoma infestans, in an urban community of Arequipa, Peru, and to evaluate the effect of deltamethrin-impregnated netting on that rate. Impregnated netting decreased the rate of infestation of sentinel enclosures (rate ratio, 0.23; 95% confidence interval, 0.13-0.38; P < 0.001), controlling for the density of surrounding vector populations and the distance of these to the sentinel enclosures. Most migrant insects were early-stage nymphs, which are less likely to carry the parasitic agent of Chagas disease, Trypanosoma cruzi. Spread of the vector in the city therefore likely precedes spread of the parasite. Netting was particularly effective against adult insects and late-stage nymphs; taking into account population structure, netting decreased the reproductive value of migrant populations from 443.6 to 40.5. Impregnated netting can slow the spread of T. infestans and is a potentially valuable tool in the control of Chagas disease.     

Genome-Wide Association Study for Age-Related Hearing Loss (AHL) in the Mouse: A Meta-Analysis

Age-related hearing loss (AHL) is characterized by a symmetric sensorineural hearing loss primarily in high frequencies and individuals have different levels of susceptibility to AHL. Heritability studies have shown that the sources of this variance are both genetic and environmental, with approximately half of the variance attributable to hereditary factors as reported by Huag and Tang (Eur Arch Otorhinolaryngol 267(8):1179–1191, 2010). Only a limited number of large-scale association studies for AHL have been undertaken in humans, to date. An alternate and complementary approach to these human studies is through the use of mouse models. Advantages of mouse models include that the environment can be more carefully controlled, measurements can be replicated in genetically identical animals, and the proportion of the variability explained by genetic variation is increased. Complex traits in mouse strains have been shown to have higher heritability and genetic loci often have stronger effects on the trait compared to humans. Motivated by these advantages, we have performed the first genome-wide association study of its kind in the mouse by combining several data sets in a meta-analysis to identify loci associated with age-related hearing loss. We identified five genome-wide significant loci (<10⁻⁶). One of these loci confirmed a previously identified locus (ahl8) on distal chromosome 11 and greatly narrowed the candidate region. Specifically, the most significant associated SNP is located 450 kb upstream of Fscn2. These data confirm the utility of this approach and provide new high-resolution mapping information about variation within the mouse genome associated with hearing loss.     

Cr(VI) induces DNA damage, cell cycle arrest and polyploidization: a flow cytometric and comet assay study in Pisum sativum

Chromium(VI) is recognized as the most toxic valency of Cr, but its genotoxicity and cytostaticity in plants is still poorly studied. In order to analyze Cr(VI) cyto- and gentotoxicity, Pisum sativum L. plants were grown in soil and watered with solutions with different concentrations of Cr up to 2000 mg/L. After 28 days of exposure, leaves showed no significant variations in either cell cycle dynamics or ploidy level. As for DNA damage, flow cytometric (FCM) histograms showed significant differences in full peak coefficient of variation (FPCV) values, suggesting clastogenicity. This is paralleled by the Comet assay results, showing an increase in DNA damage for 1000 and 2000 mg/L. In roots, exposure to 2000 mg/L resulted in cell cycle arrest at the G(2)/M checkpoint. It was also verified that under the same conditions 40% of the individuals analyzed suffered polyploidization having both 2C and 4C levels. DNA damage analysis by the Comet assay and FCM revealed dose-dependent increases in DNA damage and FPCV. Through this, we have unequivocally demonstrated for the first time in plants that Cr exposure can result in DNA damage, cell cycle arrest, and polyploidization. Moreover, we critically compare the validity of the Comet assay and FCM in evaluating cytogenetic toxicity tests in plants and demonstrate that the data provided by both techniques complement each other and present high correlation levels. In conclusion, the data presented provides new insight on Cr effects in plants in general and supports the use of the parameters tested in this study as reliable endpoints for this metal toxicity in plants.     

Non heart-beating donors in England

When transplantation started all organs were retrieved from patients immediately after cardio-respiratory arrest, i.e. from non heart-beating donors. After the recognition that death resulted from irreversible damage to the brainstem, organ retrieval rapidly switched to patients certified dead after brainstem testing. These heart-beating-donors have become the principal source of organs for transplantation for the last 30 years. The number of heart-beating-donors are declining and this is likely to continue, therefore cadaveric organs from non-heart-beating donor offers a large potential of resources for organ transplantation. The aim of this study is to examine clinical outcomes of non-heart-beating donors in the past 10 years in the UK as an way of decreasing pressure in the huge waiting list for organs transplantation.     

Diabetes: insulin resistance and derangements in lipid metabolism. Cure through intervention in fat transport and storage

We present multiple findings on derangements in lipid metabolism in type 2 diabetes. The increase in the intracellular deposition of triglycerides (TG) in muscles, liver and pancreas in subjects prone to diabetes is well documented and demonstrated to attenuate glucose metabolism by interfering with insulin signaling and insulin secretion. The obesity often associated with type 2 diabetes is mainly central, resulting in the overload of abdominal adipocytes with TG and reducing fat depot capacity to protect other tissues from utilizing a large proportion of dietary fat. In contrast to subcutaneous adipocytes, the central adipocytes exhibit a high rate of basal lipolysis and are highly sensitive to fat mobilizing hormones, but respond poorly to lipolysis restraining insulin. The enlarged visceral adipocytes are flooding the portal circulation with free fatty acids (FFA) at metabolically inappropriate time, when FFA should be oxidized, thus exposing nonadipose tissues to fat excess. This leads to ectopic TG accumulation in muscles, liver and pancreatic beta-cells, resulting in insulin resistance and beta-cell dysfunction. This situation, based on a large number of observations in humans and experimental animals, confirms that peripheral adipose tissue is closely regulated, performing a vital role of buffering fluxes of FFA in the circulation. The central adipose tissues tend to upset this balance by releasing large amounts of FFA. To reduce the excessive fat outflow from the abdominal depots and prevent the ectopic fat deposition it is important to decrease the volume of central fat stores or increase the peripheral fat stores. One possibility is to downregulate the activity of lipoprotein lipase, which is overexpressed in abdominal relatively to subcutaneous fat stores. This can be achieved by gastrointestinal bypass or gastroplasty, which decrease dietary fat absorption, or by direct means that include surgical removal of mesenteric fat. Indirect treatment consists of the compliant application of drastic lifestyle change comprising both diet and exercise and pharmacotherapy that reduces mesenteric fat mass and activity. The first step should be an attempt to effectively induce a lifestyle change. Next comes pharmacotherapy including acarbose, metformin, PPARgamma, or PPARgammaalpha agonists, statins and orlistat, estrogens in postmenopausal women or testosterone in men. Among surgical procedures, gastric bypass has been proven to produce beneficial results in advance of other surgical techniques, the evidence basis of which still needs strengthening.     

Endovascular therapy of spontaneous aortocaval fistulae associated with abdominal aortic aneurysms

We report a case of an abdominal aortic aneurysm (AAA) associated with an aortocaval fistula managed with endovascular techniques. The patient had a known AAA, and on the latest computed follow-up tomographic scan, evidence of fistulization between the aorta and the vena cava was suggested, which was later corroborated by standard contrast angiography. His comorbidities precluded an open repair, and this prompted consideration for an endovascular intervention. Successful exclusion of the AAA was performed, with no evidence of endoleaks or persistence of the fistula. The endovascular approach provides an efficacious alternative to traditional methods for repair of an aortocaval fistula, which is especially important in elderly patients with several comorbidities.