The Pla surface protease/adhesin of Yersinia pestis mediates bacterial invasion into human endothelial cells

AbstractThe plasminogen activator Pla of Yersinia pestis belongs to the omptin family of enterobacterial surface proteases and is responsible for the highly efficient invasion of the plague bacterium from the subcutaneous infection site into the circulation. Y. pestis has been reported to invade human epithelial cells. Here, we investigated the role of Pla in bacterial invasion into human endothelial cells. Expression of Pla in recombinant Escherichia coli XL1(pMRK1) enhanced bacterial invasion into ECV304 cells. The invasiveness was not affected by substitution mutation at the residues S99 or D206 that are needed for the proteolytic activity of Pla. Pla-expressing bacteria adhered to the extracellular matrix of ECV304 cells. Only weak adhesion and poor invasion were seen with the recombinant E. coli XL1(pMRK2), which expresses the omptin homolog from E. coli. The results identify Pla as an invasion protein of Y. pestis and show that the invasive function does not involve the proteolytic activity of Pla

Menopausal transition alters female skeletal muscle transcriptome

Objectives Although skeletal muscle is a target of hormonal regulation, the muscle transcriptome, including messenger-RNA (mRNA), long non-coding RNAs (lncRNAs), and microRNAs (miRNAs) has not previously been studied across the menopausal transition. Thus, we took a multi-RNA-omics approach to get insight into transcriptome-wide events of menopause. Methods We included baseline and follow-up muscle samples from seven early (EarlyMT) and 17 late perimenopausal (LateMT) women transitioning to early postmenopause during the study. Total RNA was sequenced and differential expression (DE) of the transcriptome was investigated. Gene functions were investigated with pathway analyses and protein level expression with Western Blot. Results We found 30 DE mRNA genes in EarlyMT and 19 in LateMT participating in pathways controlling cell death, growth, and interactions with the external environment. Lack of protein level changes may indicate a specific role of the regulatory RNAs during menopause. 10 DE lncRNA transcripts but no DE lncRNA genes were identified. No DE miRNAs were found. We identified putative regulatory networks likely to be affected by estradiol availability. Changes in gene expression were correlated with changes in body composition variables, indicating that muscularity and adiposity regulators are affected by menopausal transition. We also found correlations between gene expression and physical activity levels. Conclusions The observed DE genes and their regulatory networks offer novel mechanistic insights into factors affecting body composition during and after menopause. Our results imply that physiological deteriorations orchestrated by the muscle transcriptome likely depend on the magnitude of hormonal change and are influenced by physical activity

Association between neighbourhood characteristics and antidepressant use at older ages: A register-based study of urban areas in three European countries

Background: Research evidence on the association between neighbourhood characteristics and individual mental health at older ages is inconsistent, possibly due to heterogeneity in the measurement of mental-health outcomes, neighbourhood characteristics and confounders. Register-based data enabled us to avoid these problems in this longitudinal study on the associations between socioeconomic and physical neighbourhood characteristics and individual antidepressant use in three national contexts. Methods: We used register-based longitudinal data on the population aged 50+ from Turin (Italy), Stockholm (Sweden), and the nine largest cities in Finland linked to satellite-based land-cover data. This included individual-level information on sociodemographic factors and antidepressant use, and on neighbourhood soci

pH-Dependent Association of Enolase and Glyceraldehyde-3-Phosphate Dehydrogenase of Lactobacillus crispatus with the Cell Wall and Lipoteichoic Acids▿

The plasminogen-binding proteins enolase and glyceraldehyde-3-phosphate dehydrogenase of Lactobacillus crispatus were localized on the cell surface at pH 5 but released into the medium at an alkaline pH. These proteins bound to lipoteichoic acids at a pH below their isoelectric point. The results indicate that lactobacilli rapidly modify their surface properties in response to changes in pH