Search

Purpose: Mid-upper arm circumference (MUAC) is a simple, noninvasive anthropometric indicator. This study evaluated the applicability of MUAC as an alternative screening instrument to appendicular skeletal muscle mass index (ASMI) for detecting sarcopenia, and determined the optimal MUAC cutoff values. Patients and Methods: A total of 4509 subjects ≥ 50 years of age from the West China Health and Aging Trend study were included in the present study. ASM was measured by bioelectrical impedance analysis. MUAC, calf circumference (CC), and grip strength were evaluated and the Short Physical Performance Battery and 3-m timed up-and-go test were administered. Low muscle mass was diagnosed based on Asian Working Group for Sarcopenia 2019 (AWGS2019) and updated European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. Results: ASMI was positively correlated with MUAC in both men (r=0.726, P< 0.001) and women (r=0.698, P< 0.001). The area under the receiver operating characteristic curve (AUC) for MUAC as an indicator of low muscle mass in men and women was 0.86 (95% confidence interval [CI]: 0.85– 0.88) and 0.85 (95% CI: 0.84– 0.86), respectively, according to AWGS2019 criteria; and 0.86 (95% CI: 0.85– 0.88) and 0.86 (95% CI: 0.85– 0.88), respectively, according to EWGSOP2 criteria. Optimal MUAC cutoff values for predicting low muscle mass were ≤ 28.6 cm for men and ≤ 27.5 cm for women. There was no significant difference between the AUCs of MUAC and CC in men according to the 2 reference standards (P=0.809), whereas the AUC of CC was superior to that of MUAC in women according to AWGS2019 (P< 0.001) and EWGSOP2 (P=0.008) criteria. Conclusion: MUAC is strongly correlated with ASMI among community-dwelling middle-aged and older adults in China. MUAC can be used as a simple screening instrument to ASMI for diagnosing sarcopenia, especially in men. [ABSTRACT FROM AUTHOR]

The carbon catabolite repressor protein 4 (CCR4)-negative on TATA (NOT) complex includes multiple subunits and is conserved in the eukaryotic cells. The CCR4-NOT complex can regulate gene expression at different levels. Two subunits of the CCR4-NOT complex, CCR4 and CCR4-associated factor 1 (CAF1), possess deadenylase activity. In yeast, the deadenylase activity is mainly provided by the CCR4 subunit; however, the deadenylase activity is provided by both CCR4 and CAF1 in other eukaryotes. A previous study reported that CAF1 but not CCR4 is required for the decay of a reporter mRNA with AU-rich elements. Our previous study showed that CAF1 is involved in the regulation of intercellular adhesion molecule-1 (ICAM-1) and interleukin-8 (IL-8) expression. Both ICAM-1 and IL-8 play crucial roles in acute lung injury. In the present study, we examined the effects of CAF1 deficiency on IL-8 and ICAM-1 expression and acute lung injury in mice. Here we showed that there were no differences between the wild-type and CAF1-knockout mice on phenotypes. The lung histology and protein and mRNA levels of IL-8 and ICAM-1 in unstimulated wild-type mice were comparable to those in unstimulated CAF1-knockout mice. However, lipopolysaccharide stimulation led to more severe lung histological injury and greatly higher IL-8 and ICAM-1 expression in CAF1-knockout mice compared to the wild-type mice. These results, together with our previous study, suggest that CAF1 is involved in the regulation of lipopolysaccharide-stimulated IL-8 and ICAM-1 expression in vivo and affects the progression of acute lung injury. [ABSTRACT FROM AUTHOR]