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A higher body mass index (BMI) is associated with shorter telomeres. The loss of muscle mass with aging is associated with adverse outcomes. The appendicular skeletal muscle index (ASMI) is currently used to quantify muscle mass. We investigated the association of the ASMI with leukocyte telomere length in adult Americans. This cross-sectional study used the National Health and Nutrition Examination Survey (NHANES) 1999–2002 dataset. Body composition was measured by dual-energy X-ray absorptiometry. Low muscle mass was defined using sex-specific thresholds of the appendicular skeletal muscle mass index (ASMI). The telomere-to-single-copy gene ratio (T/S ratio) was converted to base pairs. Generalized linear models were performed to evaluate the association of ASMI with telomere length. In multivariable adjustment regression models, higher ASMI was associated with longer telomeres in US adults (β = 70.2, P < 0.001, P trend<0.001). In participants with preserved muscle mass, the ASMI was related to longer telomere length (β = 75.1, P < 0.001), but not significantly in low muscle mass participants (β = 68.7, P = 0.30). Further subgroup analysis by a combination of age groups and muscle mass status showed positive association with young-preserved muscle mass (β = 82.6, P < 0.001), old-preserved muscle mass (β = 44.4, P = 0.12), young-low muscle mass (β = 135.4, P = 0.20), and old-low muscle mass (β = 52.7, P = 0.55). Because each additional year of chronological age was associated with telomeres that were 15.3 base pairs shorter, on average, this would equate to 5.4 fewer years of biological aging (82.6 ÷ 15.3) in the young-preserved muscle mass participants. A higher ASMI is associated with longer telomeres. The prevention of skeletal muscle loss has the potential to delay telomere shortening and account for less biological aging. In young people with preserved muscle mass, for every 1 kg/m2 increase in the ASMI, telomere will be extended by 82.6 bp; this would equate to 5.4 fewer years of biological aging (82.6 base pairs/15.3). [Display omitted] [ABSTRACT FROM AUTHOR]

Objective To evaluate the change in mandibular second-molar (M2) angulation in orthodontic treatment with premolar extraction and lower third molar (M3). Study Design Panoramic radiographs were evaluated in 3 groups of 129 participants: (1) control, no orthodontic treatment (n = 65); (2) extraction, orthodontic treatment with premolar extraction (n = 30); and (3) nonextraction, orthodontic treatment without premolar extraction (n = 34). The angular difference and ratio of M2 to the first molar (M1), the change in the angulation of M2 between pre- and postorthodontic treatment, and the distal bone level of M2 were assessed. Results The angular difference and ratio of M2 to M1, the angulation change of M2 between pre- and postorthodontic treatment, and the distal bone level of M2 were higher in the nonextraction group than in the control and extraction groups. Conclusions The successful orthodontic alignment of the M2 may not be achieved in nonextraction cases when the M3s are present. [ABSTRACT FROM AUTHOR]

• First frameshift mutation in the GHRH gene was identified in a Chinese boy with IGHD. • Mutant GHRH showed increased expression level and altered intracellular localization. • Mutant GHRH had reduced capacity to stimulate GH secretion in GH3 cells. • GHRH haploinsufficiency might be a potential molecular etiology of IGHD. Isolated growth hormone deficiency (IGHD) is a rare genetically heterogeneous disorder caused primarily by mutations in GH1 and GH releasing hormone receptor (GHRHR). The aim of this study was to identify the molecular etiology of a Chinese boy with IGHD. Whole-exome sequencing, sanger sequencing and bioinformatic analysis were performed to screen for candidate mutations. The impacts of candidate mutation on gene expression, intracellular localization and protein function were further evaluated by in vitro assays. A novel heterozygous frameshift mutation in the GHRH gene (c.91dupC, p.R31Pfs*98) was identified in a Chinese boy clinically diagnosed as having IGHD. The mutation was absent in multiple public databases, and considered as deleterious using in silico prediction, conservative analysis and three-dimensional homology modeling. Furthermore, mRNA and protein expression levels of mutant GHRH were significantly increased than wild-type GHRH (p < 0.05). Moreover, mutant GHRH showed an aberrant accumulation within the cytoplasm, and obviously reduced ability to stimulate GH secretion and cAMP accumulation in human GHRHR-expressing pituitary GH3 cells compared to wild-type GHRH (p < 0.05). Our study discovered the first loss-of function mutation of GHRH in a Chinese boy with IGHD and provided new insights on IGHD pathogenesis caused by GHRH haploinsufficiency. [ABSTRACT FROM AUTHOR]

Background Nurses play an important role in medical and health services but anxiety among those in this profession is widespread. Anxiety not only damages the physical and mental health of the individual, but also reduces the efficiency of their work and the quality of care, ultimately impacting on patient care. Therefore, it is necessary to elucidate the factors that lead to anxiety and explore measures to reduce the impact these factors have on nurses. Objective The purpose of this study was to investigate the serial-multiple mediation of psychological capital (PsyCap), organizational commitment, job burnout, and anxiety among Chinese female nurses. Design A cross-sectional stratified cluster sampling study. Participants The study consisted of 1354 Chinese female nurses from two tertiary grade A hospitals in Heilongjiang Province, China. Methods The Zung Self-Rating Anxiety Scale, the Chinese psychological capital questionnaire, the Chinese Maslach Burnout Inventory, and the Chinese Employee Organizational Commitment Questionnaire were used to gather data. Descriptive analysis, independent-samples T -test, one-way analysis of variance, Spearman correlation analyses, ordinary least-squares regression and the bootstrap method were used to analyze data. Results The prevalence rate of anxiety among nurses was found to be 41.1%, and there were significant differences in anxiety symptoms in age (F = 15.54, p < 0.001) and marital status (F = 5.41, p < 0.001), but not education (F = 1.50, p = 0.224) among nurses. Overall, the serial-multiple mediation of organizational commitment and job burnout in the relationship between PsyCap and anxiety was found to be statistically significant. Conclusions The results of the present study showed that positive PsyCap was sequentially associated with increased organizational commitment first, and then decreased job burnout, which was in turn related to reduced symptoms of anxiety among female nurses. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most common bone diseases; it is characterized by bone loss and is a risk factor for hip fracture. Chinese herbal medicines (CHMs) and their related natural compounds have been used for treating many diseases, including bone diseases, since ancient times in China and are regarded as a cost-effective complementary therapy. The goal of this study was to investigate the osteoprotective mechanisms of these three Chinese herbs and their related natural compounds. The effects of CHMs and related natural compounds on RANKL-induced osteoclastogenesis in vitro were investigated. A network pharmacology method was applied to study CHM-related natural compounds and their osteoporosis targets. In addition, their effect on RANKL-induced osteoclastogenesis in RAW264.7 cells was also investigated in vitro. Radix dipsaci , Eucommiae cortex , and Rhizoma drynariae exhibited protective effects against mortality in hip fracture patients. Furthermore, these three herbs inhibited RANKL-induced TRAP activities and reduced the expression of bone resorption-related genes in RAW264.7 cells. Network analysis of natural compound (ingredient)-target interactions identified 11 natural compounds. Signal pathway analyses suggested that these compounds may target cytokine-cytokine receptor interactions, including RANKL-induced osteoclastogenesis. Five novel natural compounds exhibited reduced RANKL-induced TRAP activities and bone resorption-related gene expression. The clinically used CHMs, Radix dipsaci , Eucommiae cortex , and Rhizoma drynariae , and natural compounds obtained from them may suppress RANKL-induced osteoclastogenesis in vitro. Image 1 [ABSTRACT FROM AUTHOR]