eScholarship@UMMS

Objectives

To test whether women aged 55 and older with increasing evidence of a frailty phenotype would have greater risk of fractures, disability, and recurrent falls than women who were not frail, across geographic areas (Australia, Europe, and North America) and age groups.

Design

Multinational, longitudinal, observational cohort study.

Setting

Global Longitudinal Study of Osteoporosis in Women (GLOW).

Participants

Women (N = 48,636) aged 55 and older enrolled at sites in Australia, Europe, and North America.

Measurements

Components of frailty (slowness and weakness, poor endurance and exhaustion, physical activity, and unintentional weight loss) at baseline and report of fracture, disability, and recurrent falls at 1 year of follow-up were investigated. Women also reported health and demographic characteristics at baseline.

Results

Women younger than 75 from the United States were more likely to be prefrail and frail than those from Australia, Canada, and Europe. The distribution of frailty was similar according to region for women aged 75 and older. Odds ratios from multivariable models for frailty versus nonfrailty were 1.23 (95% confidence interval (CI) = 1.07–1.42) for fracture, 2.29 (95% CI = 2.09–2.51) for disability, and 1.68 (95% CI = 1.54–1.83) for recurrent falls. The associations for prefrailty versus nonfrailty were weaker but still indicated statistically significantly greater risk of each outcome. Overall, associations between frailty and each outcome were similar across age and geographic region.

Conclusion

Greater evidence of a frailty phenotype is associated with greater risk of fracture, disability, and falls in women aged 55 and older in 10 countries, with similar patterns across age and geographic region.

Objective Non-alcoholic fatty liver disease (NAFLD) is associated with a higher risk of cardiovascular disease, but no data exist about the relation between NAFLD and adverse outcomes in persons with acute coronary syndromes (ACS). We evaluated elevated serum alanine aminotransferase (ALT) as a marker of NAFLD, in association adverse outcomes following ACS.

Methods We conducted a retrospective cohort study of participants enrolled in the Global Registry of Acute Coronary Events (GRACE) admitted for ACS to St Michael's Hospital, Toronto, between 1999 and 2007. Multivariable linear regression was used to determine the change in maximum measured cardiac troponin I (cTnI) per each 1 IU/l increase in serum ALT concentration. The association between an elevated ALT >90th centile, and adverse outcomes in-hospital and at 6 months were calculated using multiple logistic regression analyses, adjusting for age, sex, body mass index, serum creatinine, glucose, triglycerides and LDL-C, as well as chronic statin or other lipid-lowering agent use.

Results 528 participants were included. Each 1 IU/l increase in ALT was associated with an increase in maximum measured cTnI of 0.16 µg/l (95% CI 0.10 to 0.22). An elevated ALT concentration >90th percentile was associated with a maximum measured cTnI in the highest quartile (adjusted OR 7.07, 95% CI 1.83 to 27.37). An elevated ALT >90th percentile was also significantly associated with all-cause mortality in-hospital, and up to 6 months after discharge (adjusted OR 8.96, 95% CI 3.28 to 24.49).

Conclusions NAFLD, determined by an elevated serum ALT, is associated with a higher risk of adverse outcomes in persons with ACS. Whether ALT is a valid and independent prognostic marker in ACS remains to be determined.

Supervillin, the largest member of the villin/gelsolin family, is a cytoskeleton regulating, peripheral membrane protein. Supervillin increases cell motility and promotes invasive activity in tumors. Major cytoskeletal interactors, including filamentous actin and myosin II, bind within the unique supervillin amino terminus, amino acids 1-830. The structural features of this key region of the supervillin polypeptide are unknown. Here, we utilize circular dichroism and bioinformatics sequence analysis to demonstrate that the N-terminal part of supervillin forms an extended intrinsically disordered region (IDR). Our combined data indicate that the N-terminus of human and bovine supervillin sequences (positions 1-830) represents an IDR, which is the largest IDR known to date in the villin/gelsolin family. Moreover, this result suggests a potentially novel mechanism of regulation of myosin II and F-actin via the intrinsically disordered N-terminal region of hub protein supervillin.

The inflammasome has emerged as an important molecular protein complex which initiates proteolytic processing of pro-IL-1β and pro-IL-18 into mature inflammatory cytokines. In addition, inflammasomes initiate pyroptotic cell death that may be independent of those cytokines. Inflammasomes are central to elicit innate immune responses against many pathogens, and are key components in the induction of host defenses following bacterial infection. Here, we review recent discoveries related to NLRP1, NLRP3, NLRC4, NLRP6, NLRP7, NLRP12 and AIM2-mediated recognition of bacteria. Mechanisms for inflammasome activation and regulation are now suggested to involve kinases such as PKR and PKCδ, ligand binding proteins such as the NAIPs, and caspase-11 and caspase-8 in addition to caspase-1. Future research will determine how specific inflammasome components pair up in optimal responses to specific bacteria.