Methionine Sulfoxide Reductase A (MsrA) Deficient Mycoplasma genitalium Shows Decreased Interactions with Host Cells

Mycoplasma genitalium is an important sexually transmitted pathogen that affects both men and women. In genital-mucosal tissues, it initiates colonization of epithelial cells by attaching itself to host cells via several identified bacterial ligands and host cell surface receptors. We have previously shown that a mutant form of M. genitalium lacking methionine sulfoxide reductase A (MsrA), an antioxidant enzyme which converts oxidized methionine (Met(O)) into methionine (Met), shows decreased viability in infected animals. To gain more insights into the mechanisms by which MsrA controls M. genitalium virulence, we compared the wild-type M. genitalium strain (G37) with an msrA mutant (MS5) strain for their ability to interact with target cervical epithelial cell lines (HeLa and C33A) and THP-1 monocytic cells. Infection of epithelial cell lines with both strains revealed that MS5 was less cytotoxic to HeLa and C33A cell lines than the G37 strain. Also, the MS5 strain was more susceptible to phagocytosis by THP-1 cells than wild type strain (G37). Further, MS5 was less able to induce aggregation and differentiation in THP-1 cells than the wild type strain, as determined by carboxyfluorescein diacetate succinimidyl ester (CFSE) labeling of the cells, followed by counting of cells attached to the culture dish using image analysis. Finally, MS5 was observed to induce less proinflammatory cytokine TNF-α by THP-1 cells than wild type G37 strain. These results indicate that MsrA affects the virulence properties of M. genitalium by modulating its interaction with host cells

Governing social orders, unfolding rationality, and Jesuit accounting practices:A procedural approach to institutional logics

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Validity of two wheelchair-mounted devices for estimating wheelchair speed and distance traveled

This study evaluated the validity of two wheelchair-mounted devices—the Cateye® and Wheeler—for monitoring wheelchair speed and distance traveled. Speed estimates were validated against a calibrated treadmill at speeds from 1.5 to 10 km/hr. Twenty-five wheelchair users completed a course of known distance comprising a sequence of everyday wheelchair activities. Speed estimate validity was very good (mean absolute percentage error ≤ 5%) for the Wheeleri at all speeds and for the Cateye at speeds >3 km/hr but not speeds 20%). Wheeleri distance estimates were good (mean absolute percentage error < 10%) for linear pushing activities and general maneuvering but poor for confined-space maneuvering. Cateye estimates were good for continuous linear propulsion but poor for discontinuous pushing and maneuvering (both general and confined space). Both devices provided valid estimates of speed and distance for typical wheelchair-based exercise activities. However, the Wheeleri provided more accurate estimates of speed and distance during typical everyday wheelchair activities