SVEP1 plays a crucial role in epidermal differentiation

SVEP1 is a recently identified multidomain cell adhesion protein, homologous to the mouse polydom protein, which has been shown to mediate cell‐cell adhesion in an integrin‐dependent manner in osteogenic cells. In this study, we characterized SVEP1 function in the epidermis. SVEP1 was found by qRT‐PCR to be ubiquitously expressed in human tissues, including the skin. Confocal microscopy revealed that SVEP1 is normally mostly expressed in the cytoplasm of basal and suprabasal epidermal cells. Downregulation of SVEP1 expression in primary keratinocytes resulted in decreased expression of major epidermal differentiation markers. Similarly, SVEP1 downregulation was associated with disturbed differentiation and marked epidermal acanthosis in three‐dimensional skin equivalents. In contrast, the dispase assay failed to demonstrate significant differences in adhesion between keratinocytes expressing normal vs low levels of SVEP1. Homozygous Svep1 knockout mice were embryonic lethal. Thus, to assess the importance of SVEP1 for normal skin homoeostasis in vivo, we downregulated SVEP1 in zebrafish embryos with a Svep1‐specific splice morpholino. Scanning electron microscopy revealed a rugged epidermis with perturbed microridge formation in the centre of the keratinocytes of morphant larvae. Transmission electron microscopy analysis demonstrated abnormal epidermal cell‐cell adhesion with disadhesion between cells in Svep1‐deficient morphant larvae compared to controls. In summary, our results indicate that SVEP1 plays a critical role during epidermal differentiation.     

Selenium Cycling Across Soil-Plant-Atmosphere Interfaces: A Critical Review

Selenium (Se) is an essential element for humans and animals, which occurs ubiquitously in the environment. It is present in trace amounts in both organic and inorganic forms in marine and freshwater systems, soils, biomass and in the atmosphere. Low Se levels in certain terrestrial environments have resulted in Se deficiency in humans, while elevated Se levels in waters and soils can be toxic and result in the death of aquatic wildlife and other animals. Human dietary Se intake is largely governed by Se concentrations in plants, which are controlled by root uptake of Se as a function of soil Se concentrations, speciation and bioavailability. In addition, plants and microorganisms can biomethylate Se, which can result in a loss of Se to the atmosphere. The mobilization of Se across soil-plant-atmosphere interfaces is thus of crucial importance for human Se status. This review gives an overview of current knowledge on Se cycling with a specific focus on soil-plant-atmosphere interfaces. Sources, speciation and mobility of Se in soils and plants will be discussed as well as Se hyperaccumulation by plants, biofortification and biomethylation. Future research on Se cycling in the environment is essential to minimize the adverse health effects associated with unsafe environmental Se levels.     

The role of metabolism in the developmental toxicity of polycyclic aromatic hydrocarbon-containing extracts of petroleum substances

In vitro assays presently used for prenatal developmental toxicity (PDT) testing only assess the embryotoxic potential of parent substances and not that of potentially embryotoxic metabolites. Here we combined a biotransformation system, using hamster liver microsomes, with the ES-D3 cell differentiation assay of the embryonic stem cell test (EST) to compare the in vitro PDT potency of two 5-ring polycyclic aromatic hydrocarbons (PAHs), benzo[a]pyrene (BaP) and dibenz[a,h]anthracene (DBA), and dimethyl sulfoxide extracts from five PAH-containing petroleum substances (PS) and a gas-to-liquid base oil (GTLb), with and without bioactivation. In the absence of bioactivation, DBA, but not BaP, inhibited the differentiation of ES-D3 cells into beating cardiomyocytes in a concentration-dependent manner. Upon bioactivation, BaP induced in vitro PDT, while its major metabolite 3-hydroxybenzo[a]pyrene was shown to be active in the EST as well. This means BaP needs biotransformation to exert its embryotoxic effects. GTLb extracts tested negative in the EST, with and without bioactivation. The PS-induced PDT in the EST was not substantially changed following bioactivation, implying that metabolism may not play a crucial role for the PS extracts under study to exert the in vitro PDT effects. Altogether, these results indicate that although some PAH require bioactivation to induce PDT, some do not and this latter appears to hold for the (majority of) the PS constituents responsible for the in vitro PDT of these complex substances.     

Unexpected complication of arteriovenous fistula of the left common carotid to internal jugular vein following central venous catheterization

Incidence of inadvertent arterial puncture secondary to central venous catheter insertion is not common with an arterial puncture rate of<1%.This is due to the advancements and wide availability of ultrasound to guide its insertion.Formation of arteriovenous fistula after arterial puncture is an unexpected complication.Till date,only five cases(including this case)of acquired arteriovenous fistula formation has been described due to inadvertent common carotid puncture.The present case is a 26-year-old man sustained traumatic brain injuries,chest injuries and multiple bony fractures.During resuscitative phase,attempts at left central venous catheter via left internal jugular vein under ultrasound guidance resulted in inadvertent puncture into the left common carotid artery.Surgical neck exploration revealed that the catheter had punctured through the left internal jugular vein into the common carotid artery with formation of arteriovenous fistula.The catheter was removed successfully and common carotid artery was repaired.Postoperatively,the patient recovered and clinic visits revealed no neurological deficits.From our literature review,the safest method for removal is via endovascular and open surgical removal.The pull/push technique(direct removal with compression)is not recommended due to the high risk for stroke,bleeding and hematoma formation.     

Personal Characteristics Associated with Resident Physicians’ Self Perceptions of Preparedness to Deliver Cross-Cultural Care

BACKGROUND  Recent reports from the Institute of Medicine emphasize patient-centered care and cross-cultural training as a means of improving the quality of medical care and eliminating racial and ethnic disparities. OBJECTIVE  To determine whether, controlling for training received in medical school or during residency, resident physician socio-cultural characteristics influence self-perceived preparedness and skill in delivering cross-cultural care. DESIGN  National survey of resident physicians. PARTICIPANTS  A probability sample of residents in seven specialties in their final year of training at US academic health centers. MEASUREMENT  Nine resident characteristics were analyzed. Differences in preparedness and skill were assessed using the χ² statistic and multivariate logistic regression. RESULTS  Fifty-eight percent (2047/3500) of residents responded. The most important factor associated with improved perceived skill level in performing selected tasks or services believed to be useful in treating culturally diverse patients was having received cross-cultural skills training during residency (OR range 1.71–4.22). Compared with white residents, African American physicians felt more prepared to deal with patients with distrust in the US healthcare system (OR 1.63) and with racial or ethnic minorities (OR 1.61), Latinos reported feeling more prepared to deal with new immigrants (OR 1.88) and Asians reported feeling more prepared to deal with patients with health beliefs at odds with Western medicine (1.43). CONCLUSIONS  Cross-cultural care skills training is associated with increased self-perceived preparedness to care for diverse patient populations providing support for the importance of such training in graduate medical education. In addition, selected resident characteristics are associated with being more or less prepared for different aspects of cross-cultural care. This underscores the need to both include medical residents from diverse backgrounds in all training programs and tailor such programs to individual resident needs in order to maximize the chances that such training is likely to have an impact on the quality of care.     

Accuracy in the estimation of body weight: an alternate test of the motivated-distortion hypothesis

OBJECTIVE: Inaccuracies in self-reported weight are believed to represent a motivated distortion, but cognitive or perceptual biases have not been excluded. We examined the ability of participants to estimate the weight of a target person as a means of distinguishing between motivated distortions and perceptual biases. METHOD: Participants (restrained eaters and unrestrained eaters; women and men) estimated the weight of a target individual, which was compared with the actual weight of the target individual. RESULTS: Restrained and unrestrained eaters did not differ in their estimates of the target's weight, and men underestimated the target's weight to a greater extent than did women. DISCUSSION: The pattern of inaccuracies observed does not parallel those found in research on self-reported weight. This observation suggests that perceptual biases do not explain inaccuracies in self-reported weight and that such inaccuracies may be the result of motivated distortions. Issues regarding data analysis and presentation are also discussed.