A novel class of CoA-transferase involved in short-chain fatty acid metabolism in butyrate-producing human colonic bacteria

Peer reviewedPublisher PD

Serum Concentrations of Myostatin and Myostatin-Interacting Proteins do not differ between young and Scarcopenic elderly men

Peer reviewedPostprin

Производительность труда на предприятии: оценка и направления повышения (на примере ОАО «Гомельский завод станочных узлов»)

Penicillin-binding proteins (PBPs) are enzymes responsible for the polymerization of the glycan strand and the cross-linking between glycan chains as well as the target proteins for beta-lactam antibiotics. Mutational alterations in PBPs can confer resistance either by reducing binding of the antibiotic to the active site or by evolving a beta-lactamase activity that degrades the antibiotic. As no systematic studies have been performed to examine the potential of all PBPs present in one bacterial species to evolve increased resistance against beta-lactam antibiotics, we explored the ability of fifteen different defined or putative PBPs in Salmonella enterica to acquire increased resistance against penicillin G. We could after mutagenesis and selection in presence of penicillin G isolate mutants with amino-acid substitutions in the PBPs, FtsI, DacB and DacC (corresponding to PBP3, PBP4 and PBP6) with increased resistance against b-lactam antibiotics. Our results suggest that: (i) most evolved PBPs became 'generalists" with increased resistance against several different classes of b-lactam antibiotics, (ii) synergistic interactions between mutations conferring antibiotic resistance are common and (iii) the mechanism of resistance of these mutants could be to make the active site more accessible for water allowing hydrolysis or less binding to b-lactam antibiotics

Sex-specific relevance of diabetes to occlusive vascular and other mortality : a collaborative meta-analysis of individual data from 980 793 adults from 68 prospective studies

Background: Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men. Methods: In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes. Findings: Individual participant-level data were analysed from 980793 adults. During 9 center dot 8 million person-years of follow-up, among participants aged between 35 and 89 years, 19686 (25 center dot 6%) of 76965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2 center dot 10, 95% CI 1 center dot 97-2 center dot 24) and tripled risk among women (3 center dot 00, 2 center dot 71-3 center dot 33; x(2) test for heterogeneity p<0 center dot 0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35-59 years: 2 center dot 60, 2 center dot 30-2 center dot 94) than in older individuals (aged 70-89 years: 2 center dot 01, 1 center dot 85-2 center dot 19; p=0 center dot 0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35-59 years had the highest death RR across all age and sex groups (5 center dot 55, 4 center dot 15-7 center dot 44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35-59 years, the excess absolute risk was 0 center dot 05% (95% CI 0 center dot 03-0 center dot 07) per year in women compared with 0 center dot 08% (0 center dot 05-0 center dot 10) per year in men; the corresponding excess at ages 70-89 years was 1 center dot 08% (0 center dot 84-1 center dot 3 2) per year in women and 0 center dot 91% (0 center dot 77-1 center dot 05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes. Interpretation: Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained

Insights into substrate stabilization from snapshots of the peptidyl transferase center of the intact 70S ribosome

Protein synthesis is catalyzed in the peptidyl transferase center (PTC), located in the large (50S) subunit of the ribosome. No high-resolution structure of the intact ribosome has contained a complete active site including both A- and P-site tRNAs. In addition, although past structures of the 50S subunit have found no ordered proteins at the PTC, biochemical evidence suggests that specific proteins are capable of interacting with the 3′ ends of tRNA ligands. Here we present structures, at 3.6-Å and 3.5-Å resolution respectively, of the 70S ribosome in complex with A- and P-site tRNAs that mimic pre- and post-peptidyl-transfer states. These structures demonstrate that the PTC is very similar between the 50S subunit and the intact ribosome. They also reveal interactions between the ribosomal proteins L16 and L27 and the tRNA substrates, helping to elucidate the role of these proteins in peptidyl transfer

Menopausal hormone use and ovarian cancer risk: individual participant meta-analysis of 52 epidemiological studies

Background Half the epidemiological studies with information about menopausal hormone therapy and ovarian cancer risk remain unpublished, and some retrospective studies could have been biased by selective participation or recall. We aimed to assess with minimal bias the effects of hormone therapy on ovarian cancer risk. Methods Individual participant datasets from 52 epidemiological studies were analysed centrally. The principal analyses involved the prospective studies (with last hormone therapy use extrapolated forwards for up to 4 years). Sensitivity analyses included the retrospective studies. Adjusted Poisson regressions yielded relative risks (RRs) versus never-use. Findings During prospective follow-up, 12 110 postmenopausal women, 55% (6601) of whom had used hormone therapy, developed ovarian cancer. Among women last recorded as current users, risk was increased even with <5 years of use (RR 1·43, 95% CI 1·31–1·56; p<0·0001). Combining current-or-recent use (any duration, but stopped <5 years before diagnosis) resulted in an RR of 1·37 (95% CI 1·29–1·46; p<0·0001); this risk was similar in European and American prospective studies and for oestrogen-only and oestrogen-progestagen preparations, but differed across the four main tumour types (heterogeneity p<0·0001), being definitely increased only for the two most common types, serous (RR 1·53, 95% CI 1·40–1·66; p<0·0001) and endometrioid (1·42, 1·20–1·67; p<0·0001). Risk declined the longer ago use had ceased, although about 10 years after stopping long-duration hormone therapy use there was still an excess of serous or endometrioid tumours (RR 1·25, 95% CI 1·07–1·46, p=0·005). Interpretation The increased risk may well be largely or wholly causal; if it is, women who use hormone therapy for 5 years from around age 50 years have about one extra ovarian cancer per 1000 users and, if its prognosis is typical, about one extra ovarian cancer death per 1700 users

How non-native English-speaking staff are evaluated in linguistically diverse organizations: A sociolinguistic perspective

The aim of this paper is to examine the effects of evaluations of non-native speaking staff?s spoken English in international business settings. We adopt a sociolinguistic perspective on power and inequalities in linguistically diverse organizations in an Anglophone environment. The interpretive qualitative study draws on 54 interviews with non-native English-speaking staff in 19 UK business schools. We analyze, along the dimensions of status, solidarity and dynamism, the ways in which non-native speakers, on the basis of their spoken English, are evaluated by themselves and by listeners. We show how such evaluations refer to issues beyond the speaker?s linguistic fluency, and have consequences for her or his actions. The study contributes to the literature on language and power in international business through offering fine-grained insights into and elucidating how the interconnected evaluative processes impact the formation and perpetuation of organizational power relations and inequalities. It also puts forward implications for managing the officially monolingual, yet linguistically diverse organizations

Language in international business: a review and agenda for future research

A fast growing number of studies demonstrates that language diversity influences almost all management decisions in modern multinational corporations. Whereas no doubt remains about the practical importance of language, the empirical investigation and theoretical conceptualization of its complex and multifaceted effects still presents a substantial challenge. To summarize and evaluate the current state of the literature in a coherent picture informing future research, we systematically review 264 articles on language in international business. We scrutinize the geographic distributions of data, evaluate the field’s achievements to date in terms of theories and methodologies, and summarize core findings by individual, group, firm, and country levels of analysis. For each of these dimensions, we then put forward a future research agenda. We encourage scholars to transcend disciplinary boundaries and to draw on, integrate, and test a variety of theories from disciplines such as psychology, linguistics, and neuroscience to gain a more profound understanding of language in international business. We advocate more multi-level studies and cross-national research collaborations and suggest greater attention to potential new data sources and means of analysis