EFECT OF SMOKING ON THE ACCUMULATION OF POLYCYCLIC AROMATIC HIDROCARBONS, IN M. LONGISIMUS DORSI FROM PIGS AND POSSIBILITIES FOR REDUCING THEIR CONTENT

This study deals with the effect of smoking process and the accumulation of toxic polycyclic aromatic hydrocarbons in Musculus Longissimus dorsi from pigs and studies the possibilities to reduce their content. The studies were conducted on two samples boiled-smoked fillet – one salted with brine and added proteincoating, whereas the second one salted with brine and added ascorbic acid.Qualitative identification and quantification of polycyclic aromatic hydrocarbons is done by gas hromotograph Hewlett Packard 5890 with LG 85 B spectrophotometric detector. It was found that the use of proteincoatings, significantly reduces the amount of polycyclic aromatic hydrocarbons in the smoking of Musculus Longissimus dorsi from pigs. The addition of ascorbic acid in conjunction with protein salting coatings technology represents a significant option for reducing the content of the benzo(a)pyrene , which contributes to the safety in the final products. In studies of the samples of proteins and ascorbic acid, the inner layers i.e the muscle tissue was found to contain significantly less amount of benzo(a)pyrene (1,75 ± 0,06 μ/kg) compared with the values found in the surface layers (2,31 ± 0,02 μg/kg)

A comparative study of mental health of medical students in two countries

Results from many studies indicate that throughout medical education students experience high levels of stress and depression. The aim of the current study was to assess and compare Bulgarian and Turkish medical students' levels of stress and depression. A cross-sectional study was conducted with 546 students (276 foreign students from Medical University – Sofia and 270 medical students from several medical universities in Ankara). The study instrument included basic socio-demographic questions, Medical Student Stressor Questionnaire (MSSQ-40 items) and Beck Depression Inventory (BDI). Turkish medical students showed higher levels of stress and depression than foreign students from Bulgaria. We found that all types of stressors in medical students had a relationship with depression. Results of our study imply that medical students need access to psychological support throughout their education

Axonemal structures reveal mechanoregulatory and disease mechanisms

Motile cilia and flagella beat rhythmically on the surface of cells to power the flow of fluid and to enable spermatozoa and unicellular eukaryotes to swim. In humans, defective ciliary motility can lead to male infertility and a congenital disorder called primary ciliary dyskinesia (PCD), in which impaired clearance of mucus by the cilia causes chronic respiratory infections1. Ciliary movement is generated by the axoneme, a molecular machine consisting of microtubules, ATP-powered dynein motors and regulatory complexes2. The size and complexity of the axoneme has so far prevented the development of an atomic model, hindering efforts to understand how it functions. Here we capitalize on recent developments in artificial intelligence-enabled structure prediction and cryo-electron microscopy (cryo-EM) to determine the structure of the 96-nm modular repeats of axonemes from the flagella of the alga Chlamydomonas reinhardtii and human respiratory cilia. Our atomic models provide insights into the conservation and specialization of axonemes, the interconnectivity between dyneins and their regulators, and the mechanisms that maintain axonemal periodicity. Correlated conformational changes in mechanoregulatory complexes with their associated axonemal dynein motors provide a mechanism for the long-hypothesized mechanotransduction pathway to regulate ciliary motility. Structures of respiratory-cilia doublet microtubules from four individuals with PCD reveal how the loss of individual docking factors can selectively eradicate periodically repeating structures

Interaction between Amyloid Beta Peptide and an Aggregation Blocker Peptide Mimicking Islet Amyloid Polypeptide

Assembly of amyloid-beta peptide (Aβ) into cytotoxic oligomeric and fibrillar aggregates is believed to be a major pathologic event in Alzheimer's disease (AD) and interfering with Aβ aggregation is an important strategy in the development of novel therapeutic approaches. Prior studies have shown that the double N-methylated analogue of islet amyloid polypeptide (IAPP) IAPP-GI, which is a conformationally constrained IAPP analogue mimicking a non-amyloidogenic IAPP conformation, is capable of blocking cytotoxic self-assembly of Aβ. Here we investigate the interaction of IAPP-GI with Aβ40 and Aβ42 using NMR spectroscopy. The most pronounced NMR chemical shift changes were observed for residues 13–20, while residues 7–9, 15–16 as well as the C-terminal half of Aβ - that is both regions of the Aβ sequence that are converted into β-strands in amyloid fibrils - were less accessible to solvent in the presence of IAPP-GI. At the same time, interaction of IAPP-GI with Aβ resulted in a concentration-dependent co-aggregation of Aβ and IAPP-GI that was enhanced for the more aggregation prone Aβ42 peptide. On the basis of the reduced toxicity of the Aβ peptide in the presence of IAPP-GI, our data are consistent with the suggestion that IAPP-GI redirects Aβ into nontoxic “off-pathway” aggregates

Identification and Molecular Characterization of a New Ovarian Cancer Susceptibility Locus at 17q21.31

Epithelial ovarian cancer (EOC) has a heritable component that remains to be fully characterized. Most identified common susceptibility variants lie in non-protein-coding sequences. We hypothesized that variants in the 3 ′ untranslated region at putative microRNA (miRNA) binding sites represent functional targets that influence EOC susceptibility. Here, we evaluate the association between 767 miRNA binding site single nucleotide polymorphisms (miRSNPs) and EOC risk in 18,174 EOC cases and 26,134 controls from 43 studies genotyped through the Collaborative Oncological Gene-environment Study. We identify several miRSNPs associated with invasive serous EOC risk (OR=1.12, P =10−8 ) mapping to an inversion polymorphism at 17q21.31. Additional genotyping of non-miRSNPs at 17q21.31 reveals stronger signals outside the inversion ( P =10−10 ). Variation at 17q21.31 associates with neurological diseases, and our collaboration is the first to report an association with EOC susceptibility. An integrated molecular analysis in this region provides evidence for ARHGAP27 and PLEKHM1 as candidate EOC susceptibility genes