Multi-level analysis of alcohol-related injury and drinking pattern: emergency department data from 19 countries

Aim While drinking in the event is an important factor in injury occurrence, the pattern of usual drinking may also be important in risk of injury. Explored here is the relationship of an alcohol‐related injury with an individual usual drinking pattern. Design Alcohol‐related injury is examined using hierarchical linear models, taking into account individual usual volume of consumption over the past 12 months, as well as aggregate‐level detrimental drinking pattern (DDP) and alcohol policy measures. Setting Data analyzed are from emergency departments (EDs) in 19 countries, comprising three collaborative studies on alcohol and injury, all of which used a similar methodology. Participants The sample comprised 14 132 injured drinkers across 46 emergency room (ER) studies. Measurements Alcohol‐related injury was measured, separately, by any self‐reported drinking prior to injury, a blood alcohol concentration (BAC) ≥ 0.08 and self‐reported causal attribution of injury to drinking. Findings While individual usual volume strongly predicted an alcohol‐related injury for all three measures, usual drinking pattern also predicted an alcohol‐related injury (controlling for volume), with episodic heavy and frequent heavy drinking both more predictive of alcohol‐related injury than other drinking patterns. When individual usual volume and drinking pattern were controlled, DDP was no longer a significant predictor of alcohol‐related injury. Alcohol policy measures were predictive of both BAC and causal attribution (the stronger the policy the lower the rates of alcohol‐related injury). Conclusions Volume of alcohol typically consumed and occurrence of heavy drinking episodes are associated independently with incidence of alcohol‐related injury. The stronger the anti‐alcohol policies in a country, the lower the rates of alcohol‐related injury.     

RNA/DNA co-analysis from blood stains--results of a second collaborative EDNAP exercise

A second collaborative exercise on RNA/DNA co-analysis for body fluid identification and STR profiling was organized by the European DNA Profiling Group (EDNAP). Six human blood stains, two blood dilution series (5-0.001 μl blood) and, optionally, bona fide or mock casework samples of human or non-human origin were analyzed by the participating laboratories using a RNA/DNA co-extraction or solely RNA extraction method. Two novel mRNA multiplexes were used for the identification of blood: a highly sensitive duplex (HBA, HBB) and a moderately sensitive pentaplex (ALAS2, CD3G, ANK1, SPTB and PBGD). The laboratories used different chemistries and instrumentation. All of the 18 participating laboratories were able to successfully isolate and detect mRNA in dried blood stains. Thirteen laboratories simultaneously extracted RNA and DNA from individual stains and were able to utilize mRNA profiling to confirm the presence of blood and to obtain autosomal STR profiles from the blood stain donors. The positive identification of blood and good quality DNA profiles were also obtained from old and compromised casework samples. The method proved to be reproducible and sensitive using different analysis strategies. The results of this collaborative exercise involving a RNA/DNA co-extraction strategy support the potential use of an mRNA based system for the identification of blood in forensic casework that is compatible with current DNA analysis methodology.     

A typology of teaching roles and relationships for medical education

Background: Educational programs involve interactions between the instructors and the learners. In these interactions, instructors may play various roles. However, a nomenclature for relationships with learners appropriate to those roles has not been developed for medical education.

Aims: This article presents a typology of instructor’s roles to facilitate the connection of outcomes with instructional methods and to inform training sessions for instructors.

Method: Published articles in general education and medical education were searched for examples of terms used for instructor’s roles in developmental interactions. Examples were grouped and classified to develop a two-dimensional typology.

Results: The typology has eight categories on two dimensions. One dimension is the purpose for interaction: (1) knowledge transmission, (2) professional identity formation, (3) negotiating the institutional milieu, and (4) relationship building. The other dimension is dichotomous on whether the instructor is a member of the profession to which the learners aspire. Twelve terms were categorized: Advisor, Advocate, Buddy, Coach, Counselor, Facilitator, Guru, Master, Mentor, Role model, Teacher and Tutor.

Conclusions: Faculty instructors in medical education are often pressed for time, so clarifying role expectations is a low-cost scheme to enhance results. Using the typology can align instructor behavior with the desired learner outcomes and enhance efficient use of instructional time.     

Migrating and myelinating potential of subventricular zone neural progenitor cells in white matter tracts of the adult rodent brain

Adult neural stem cells in the subventricular zone (SVZ) produce neuronal progenitors that migrate along the rostral migratory stream (RMS) and generate olfactory interneurons. Here, we evaluate the migratory potential of SVZ cells outside the RMS and their capacity to generate oligodendrocytes in the adult brain. We show that SVZ cells migrate long distances when grafted into white matter tracts such as the cingulum (Ci) and corpus callosum (CC). Furthermore, 22 days postinjection, most present morphologic and phenotypic characteristics of cells committed to the oligodendrocyte lineage. Cells grafted in shiverer CC and Ci become MBP-positive oligodendrocytes, abundantly myelinating these white matter tracts. Type A progenitors are involved in this myelinating process. Altogether, this study reveals the migrating and myelinating potential of SVZ cells in a new environmental context. Therefore, SVZ cells stand as interesting candidates for the development of novel therapeutic strategies for demyelinating diseases.     

Gentamicin encapsulated within a biopolymer for the treatment of Staphylococcus aureus and Escherichia coli infected skin ulcers

Abstract

Skin wound infection requires carefully long-term treatment with an immense financial burden to healthcare systems worldwide. Various strategies such as drug delivery systems using polymer matrix from natural source have been used to enhance wound healing. Natural rubber latex (NRL) from Hevea brasiliensis has shown angiogenic and tissue repair properties. Gentamicin sulfate (GS) is a broad-spectrum antibiotic which inhibits the growth of a wide variety of microorganisms and, because of this, it has also been applied topically for treatment of local infections. The aim of this study was to develop a GS release system using NRL as matrix for Staphylococcus aureus and Escherichia coli infected skin ulcers treatment, without changing drug antibiotic properties. The matrix did not change the GS antimicrobial activity against S. aureus and E. coli strains. Moreover, the NRL-GS biomembrane did not exhibit hemolytic activity, being non-toxic to red blood cells. The eluates of NRL-GS biomembranes and GS solutions did not significantly reduce the survival of Caenorhabditis elegans worms for 24?h at any of the tested concentrations. Thus, these results emphasize that the NRL-GS biomembrane proved to be a promising biomaterial for future studies on the development of dressings for topical uses, inexpensive and practicable, keeping drug antibiotic properties against pathogens and to reduce the side effects.     

Tissue selectivity of endothelin

The effects of endothelin, a potent endogenous vasoconstrictor peptide, were examined in a range of vascular and non-vascular tissues. At concentrations that cause vasoconstriction in portal vein and aorta, the peptide strongly contracted rat uterus, trachea and vas deferens, but not guinea pig ileum. Nifedipine, a dihydropyridine calcium anatgonist, partially inhibited these contractions. Endothelin had no inotropic or chronotropic effect on the isolated rat heart. The peptide did not modulate secretion at the neuromuscular junction, from adrenal medullary cells or neutrophils, nor affect secretion or aggregation of platelets. The tissue responsiveness to endothelin was not the same as the tissue distribution of dihydropyridine receptors. This supports the idea that endothelin interacts with a specific receptor distinct from dihydropyridine sensitive calcium channels. The contractile effect of endothelin on non vascular smooth muscle suggests that the concept of endothelium dependent modulation of vascular smooth muscle tone may be extended to include epithelium dependent modulation of non vascular tissues.     

Dose-related effects of perfluorodecanoic acid on growth,feed intake and hepatic peroxisomal β-oxidation

The effects of the persistent peroxisome proliferator, perfluorodecanoic acid (PFDA), on growth, feed intake and the enzyme activities associated with peroxisomal β-oxidation were studied in female Sprague Dawley rats. Rats received one of six levels of PFDA (0, 0.3, 1.0, 3.0, 10.0 or 30.0 mg/kg/injection) in four IP doses at 2-week intervals. Rats with cumulative doses of ≤ 12.0 mg/kg did not differ from control rats in growth or feed intake, while rats receiving cumulative doses of ≥40 mg/kg lost weight and decreased their feed intake. Rats which received cumulative doses between these levels increased their feed intake but did not significantly alter their body weight. Total peroxisomal β-oxidation was decreased in a dose-related manner, whereas the liver to body weight ratio and the activities of individual enzymes comprising the peroxisomal β-oxidation system, namely fatty acyl-CoA oxidase, enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase, and thiolase, were increased. This study clearly shows that the inhibition of peroxisomal ß-oxidation by PFDA is not reflected in the in vitro measurement of the individual enzyme activities comprising this pathway.