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Sepsis-induced myopathy (SIM) has been recognized as a critical risk factor for the development of acquired muscle weakness among patients in the intensive care unit. These individuals frequently encounter inadequate dietary intake and malnutrition. With the aggravation of the severity of the person's condition, leading to increased skeletal muscle protein breakdown and reduced synthesis, which is an urgent problem to be solved in clinical nutritional treatment. Whole milk protein powder (WMPP) has promising bioactive nutrients and holds promising potential for enhancing skeletal muscle mass. The study was designed to delve into the potential effects and mechanisms of WMPP intervention for increaseing skeletal muscle mass on SIM mice. Our results clearly show that the intervention with WMPP can significantly improve the exercise capacity and skeletal muscle mass in SIM mice. It significantly increases the diameter and cross-sectional area (CSA) of skeletal muscle fibers, while effectively reducing the excessive aggregation of collagen fibers and the abnormal accumulation of adipose tissue in the skeletal muscle of SIM mice. Moreover, WMPP intervention also significantly alleviated the oxidative stress status of mitochondria, which subsequently enhanced the expression of mitochondrial metabolic enzymes. The mechanism may be associated with decreased AMPK phosphorylation in skeletal muscle tissue and simultaneously increased phosphorylation of mTOR, p70S6K1, and 4EBP-1 in SIM mice. In summary, the WMPP intervention significantly enhances exercise capacity and skeletal muscle mass while mitigating the oxidative stress status of mitochondria. Furthermore, it regulates skeletal muscle anabolism via the AMPK/mTOR signaling pathway in SIM mice. [ABSTRACT FROM AUTHOR]

Aims: Insulin resistance (IR) is an important risk factor for obesity and cardiometabolic diseases, and our previous findings have demonstrated that visceral fat area to skeletal muscle mass ratio (VSR) is significantly and positively associated with the risk of cardiometabolic diseases. Hence, this study aimed to investigate the relationship between VSR and multiorgan IR, provide a new approach to improve body composition, and set the basis for VSR to increase the incidence of cardiometabolic diseases. Materials and Methods: The study included 398 patients who underwent anthropometric and biochemical measurements, and body composition assessment. Spearman correlation analysis was used to investigate the correlation between VSR and homeostatic model assessment for insulin resistance (HOMA‐IR) as well as multiorgan IR, including homeostasis model assessment adiponectin (HOMA‐AD), adipose tissue insulin resistance (ADIPO‐IR), and hepatic insulin sensitivity (HISI). The new model that incorporated into the present study is made up of easily measured biochemical indicators and is used to predict IR. Logistic regression was used to analyze the odds ratio (OR) of VSR on the risk of multiorgan IR. The predictive value of VSR for HOMA‐IR and new model was evaluated using the receiver operating characteristic (ROC) curve. Results: VSR was significantly associated with HOMA‐IR, HOMA‐AD, ADIPO‐IR, 1/HISI, and new model (p < 0.001). With the increase of VSR, the OR increased significantly for HOMA‐IR and new model (p < 0.001). Then, multiorgan IR indicators were quantified, compared to the lowest quartile group, and increased VSR exacerbated the risk of IR in the highest quartile (ptrend < 0.001). The area under the curve for predicting IR using VSR for HOMA‐IR and new model was 0.88 for men, 0.85 for women and 0.73 for men, 0.76 for women, respectively. Conclusions: There was significant correlation between VSR and multiorgan IR, and the risk of multiorgan IR increased with increasing VSR. Trial Registration: Clinical Trial Registry identifier: ChiCTR2100044305. [ABSTRACT FROM AUTHOR]

BACKGROUND: Maca extract may regulate oxidative stress and muscle damage after exhaustive endurance exercise (EEE); however, its impact on these physiological activities remains obscure. OBJECTIVE: To examine the effects of Maca extract supplementation on oxidative stress, muscle damage and aerobic capacity after EEE. METHODS: Twenty healthy men were assigned to Maca or placebo groups and received two doses per day for 12 weeks. Pre- and post-EEE tests assessed levels of oxidative stress and muscle damage. The EEE test also recorded metrics such as time to exhaustion, peak oxygen consumption, and maximal and average heart rates. RESULTS: Post-exercise, there was no significant difference in oxidative stress markers between the Maca and placebo groups. However, the Maca group exhibited lower stress levels at both Post-4 and Post-24 in comparison to Post-0, while the placebo group only displayed a decrease at Post-4. Notably, Maca extract supplementation immediately increased catalase activity at Post-0. Though muscle damage markers did not significantly differ, the slope of CK elevation in the Maca group appeared lower than the Placebo group, suggesting Maca's potential in preventing muscle damage. However, no differences were noted on aerobic capacity markers. CONCLUSIONS: Maca extract may have some beneficial effects on reducing oxidative stress and possibly muscle damage after EEE. [ABSTRACT FROM AUTHOR]

Objective: To explore the feasibility of applying CT Hounsfield Units (HUs) for the assessment of preoperative paraspinal muscle fat infiltration (FI) in different segments in patients who underwent anterior cervical discectomy and fusion (ACDF). To compare the consistency of preoperative paraspinal muscle FI evaluations using MRI and those via CT HUs in patients who underwent ACDF surgery. Methods: Ninety-five patients (45 males and 50 females, aged 37‒71 years) who received CT and MRI examinations and underwent ACDF surgery were retrospectively analyzed. In the axial T2-weighted MR images at the median level of the C3/4, C4/5, and C5/6 segments, regions of interests (ROIs) were delineated along the boundaries of the cervical multifidus (MF) and semispinalis cervicis (Scer) muscles. Using the threshold tool in ImageJ software, areas of fat tissue and intermuscular septa within the ROI were quantified. The effective cross-sectional area (ECSA) for each side was obtained by subtracting the areas of fat tissue and intermuscular septa from the total ROI area. The ratio of the fat tissue area to the CSA was then calculated to determine the initial FI value. The depth of subcutaneous fat from the midline spinous process to the epidermis at the median plane of the C4/5 intervertebral disc was measured. The initial FI values were then divided by the depth of fat to determine the post-correction FI value. Using the Picture Archiving and Communication System (PACS), at identical segments and planes, ROIs were delineated using the same method as in MRI under a standard soft tissue window (width of 500 HU, level of 60 HU). The CT HU values were measured within these defined areas. The CT HU values from both sides are summed to obtain the total HU value for the segment. According to whether the measurement results of two sets of data follow a normal distribution, Pearson's test or Sperman's test was used to analyze the correlation. Results: On MRI, a statistically significant difference was observed in the post-correction FI only at the C3/4 segment compared to the other two segments (P < 0.05). No significant difference in the post-correction FI between the C4/5 and C5/6 segments was noted (P > 0.05). The CT HU results showed a substantial discrepancy between C3/4 and C4/5 segments and between C3/4 and C5/6 segments (P < 0.05), whereas no statistically significant difference was found in the CT HU value between the C4/5 and C5/6 segments (P > 0.05). The consistency analysis revealed a relatively strong correlation between the post-correction FI and CT HU values of the C3/4 and C4/5 segments. Furthermore, a strong correlation was detected in the variations in the measurement outcomes at the C5/6 segment. Conclusion: Patients requiring surgical treatment for the cervical spine exhibit varying degrees of FI in paraspinal muscles across different locations and segments. Evaluating the degree of FI in the paraspinal muscles of the cervical spine through CT HU values is feasible. There is considerable consistency between the post-correction FI assessed under MRI and the measurements of CT HU values in evaluating the FI of paraspinal muscles in the cervical spine. [ABSTRACT FROM AUTHOR]

Aims: Evidence regarding impact of protein intake distribution on skeletal muscle mass in older adults is limited and inconsistent. This study aims to investigate the relationship of evenness of dietary protein distribution and number of meals exceeding a threshold with appendicular skeletal muscle mass (ASM) in healthy and free-living Chinese older adults. Methods: Repeated measured data of 5689 adult participants aged ≥ 60 years from the China Health and Nutrition Survey (CHNS) 2015 and 2018 waves were analyzed. Mixed-effects linear regression model was performed to examine the relationship between coefficient of variance (CV) of protein intake across meals, number of meals ≥ 0.4 g protein/kg BW and ASM, respectively. Analyses were conducted separately for male and female. Results: The average CV of protein intake in each wave was in the range of 0.34–0.35. More than 40% male and female participants in each wave had no meal reaching 0.4 g protein/kg BW. Female participants in the highest quartile of protein intake CV had significantly lower ASM (β = -0.18, 95%CI = -0.32, -0.04) compared with those in the lowest quartile, after adjustment for multiple confounders. Significant negative trends were observed across dietary protein CV quartiles with ASM both in male (P trend = 0.043) and female (P trend = 0.007). Significant positive association between number of meals exceeding 0.4 g protein /kg BW and relative ASM were observed in females (2 meals vs. 0 meal: β = 0.003, 95%CI = 0.0007,0.006;≥3 meals vs. 0 meal: β = 0.008, 95%CI = 0.003,0.013), after adjusting for multiple covariates. Conclusions: A more even-distributed protein intake pattern and more meals reaching protein intake threshold were respectively associated with higher appendicular skeletal muscle mass in healthy and free-living older Chinese adults. Prospective studies and intervention trials are needed to confirm these cross-sectional findings. [ABSTRACT FROM AUTHOR]

Purpose: Older adults frequently encounter health challenges, such as impaired balance and muscle health, which increase risk of falls. The current study investigated the effectiveness of the proprioceptive neuromuscular facilitation (PNF) technique in improving balance and muscle health among older adults with high fall risk. Method: A total of 160 older adults with high fall risk were randomized into control and intervention groups. Over 6 months, the control group received standard interventions, while the intervention group received the same interventions and additional PNF training. Results: Both groups demonstrated improvements in balance function over time, with the intervention group exhibiting significant improvements in Berg Balance Scale scores, Timed Up and Go test times, and 30-Second Chair Stand Test counts (p < 0.05). Bone density significantly increased in the intervention group compared to the control group (p < 0.05), although no substantial differences in lower limb muscle mass were observed. Satisfaction rates were higher and fall incidents fewer in the intervention group. Conclusion: The PNF technique is effective in enhancing balance function and muscle health in older adults with high fall risk, demonstrating potential in reducing fall risk and improving quality of life among older adults. [Journal of Gerontological Nursing, 50(8), 37–44.] [ABSTRACT FROM AUTHOR]

This study develops a comprehensive genotype-phenotype model for predicting the effects of resistance training on leg press performance. A cohort of physically inactive adults (N=193) underwent 12 weeks of resistance training, and measurements of maximum isokinetic leg press peak force, muscle mass, and thickness were taken before and after the intervention. Whole-genome genotyping was performed, and genome-wide association analysis identified 85 novel SNPs significantly associated with changes in leg press strength after training. A prediction model was constructed using stepwise linear regression, incorporating seven lead SNPs that explained 40.4% of the training effect variance. The polygenic score showed a significant positive correlation with changes in leg press strength. By integrating genomic markers and phenotypic indicators, the comprehensive prediction model explained 75.4% of the variance in the training effect. Additionally, five SNPs were found to potentially impact muscle contraction, metabolism, growth, and development through their association with REACTOME pathways. Individual responses to resistance training varied, with changes in leg press strength ranging from −55.83% to 151.20%. The study highlights the importance of genetic factors in predicting training outcomes and provides insights into the potential biological functions underlying resistance training effects. The comprehensive model offers valuable guidance for personalized fitness programs based on individual genetic profiles and phenotypic characteristics. [ABSTRACT FROM AUTHOR]

With the increasing trend of global aging, sarcopenia has become a significant public health issue. Goji berry, also known as "Gou qi zi" in China, is a traditional Chinese herb that can enhance the structure and function of muscles and bones. Otherwise, previous excellent publications illustrated that plant-derived exosome-like nanoparticles can exert good bioactive functions in different aging or disease models. Thus, we issued the hypothesis that Gouqi-derived nanovesicles (GqDNVs) may also have the ability to improve skeletal muscle health, though the effect and its mechanism need to be explored. Hence, we have extracted GqDNVs from fresh berries of Lycium barbarum L. (goji) and found that the contents of GqDNVs are rich in saccharides and lipids. Based on the pathway annotations and predictions in non-targeted metabolome analysis, GqDNVs are tightly associated with the pathways in metabolism. In muscle atrophy model mice, intramuscular injection of GqDNVs improves the cross-sectional area of the quadriceps muscle, grip strength and the AMPK/SIRT1/PGC1α pathway expression. After separately inhibiting AMPK or PGC1α in C2C12 cells with dexamethasone administration, we have found that the activated AMPK plays the chief role in improving cell proliferation induced by GqDNVs. Furthermore, the energy-targeted metabolome analysis in the quadriceps muscle demonstrates that the GqDNVs up-regulate the metabolism of amino sugar and nucleotide sugar, autophagy and oxidative phosphorylation process, which indicates the activation of muscle regeneration. Besides, the Spearman rank analysis shows close associations between the quality and function of skeletal muscle, metabolites and expression levels of AMPK and SIRT1. In this study, we provide a new founding that GqDNVs can improve the quality and function of skeletal muscle accompanying the activated AMPK/SIRT1/PGC1α signaling pathway. Therefore, GqDNVs have the effect of anti-aging skeletal muscle as a potential adjuvant or complementary method or idea in future therapy and research. [ABSTRACT FROM AUTHOR]

Low birth weight (LBW) impairs the development and health of livestock by affecting postnatal growth performance and metabolic health in adulthood. Previous studies on indigenous goats in southwest China showed that LBW goat kids had higher mortality and morbidity rates, including hepatic dyslipidemia and liver damage. However, the mechanism of insulin resistance a&lowbar;ecting lipid metabolism under LBW conditions remains unclear. In this study, we conducted in vivo glucose-insulin metabolic studies, measured biochemical parameters, and analyzed related regulatory pathways. Both glucose tolerance tests and insulin tolerance tests indicated insulin resistance in LBW goat kids compared to controls (p < 0.05). The marker of insulin resistance, homeostasis model assessment (HOMA), was 2.85-fold higher in LBW than in control goats (p < 0.01). Additionally, elevated levels of free fatty acids in both plasma and skeletal muscle were observed in LBW goats compared to normal birth weight (NBW) goats (p < 0.05). Transcriptome analysis revealed impairments in lipid metabolism and insulin signaling in LBW goats. The observed lipid accumulation was associated with the upregulation of genes linked to fatty acid uptake and transport (FABP3), fatty acid oxidation (PPARA), triacylglycerol synthesis (LPIN1 and DGAT1), oxidative stress (ANKRD2), and insulin resistance (PGC1α). Furthermore, the insulin receptor substrate 2 (IRS2) was lower in the liver of LBW goat kids (p < 0.05). While there was no change in insulin function in skeletal muscle, LBW may lead to lipid accumulation in skeletal muscle by interfering with insulin function in the liver. These findings collectively impact the health and growth performance of livestock. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epidemiological research data on sarcopenia in China are concentrated in some provincial capitals and developed areas, while research on sarcopenia in the elderly in the Yunnan-Guizhou Plateau is at the initial stage, and there is still a lack of understanding of the development mechanism, influencing factors and prevention methods of sarcopenia. OBJECTIVE: Based on the 2019 Asian Sarcopenia Working Group Standard (AWGS2019), to assess sarcopenia in the elderly in the Yunnan-Guizhou Plateau, while analyzing the prevalence and risk factors of sarcopenia in the elderly. METHODS: A total of 1 327 elderly study subjects (650 males and 677 females) were recruited and their socio-demographic characteristics, clinical data and physical activity levels were collected. The prevalence of sarcopenia was screened using the AWGS2019 criteria. The possible influencing factors for sarcopenia were screened by univariate analysis, including χ2 test for comparing count data and t-test for comparing measurement data, and the indicators through univariate screening were included in the binary logistic regression model to assess the risk factors for sarcopenia, and then the odds ratio (OR) and 95% confidence interval (CI) were calculated. RESULTS AND CONCLUSION: The prevalence of sarcopenia in the elderly in the Yunnan-Guizhou Plateau was 14.62% (12.73% male and 16.49% female). Aging (OR=1.158, 95% CI: 1.133-1.185), female (OR=2.416, 95% CI: 1.629-3.586), fasting blood glucose ≥ 7.0 mmol/L (OR=1.653, 95% CI: 1.071-2.551), smoking (OR=1.595, 95% CI: 1.043-2.438) and a low physical activity level (OR=1.778, 95% CI: 1.154-2.737) were all independent risk factors for sarcopenia, while body mass index was a protective factor for sarcopenia (OR=0.708, 95% CI: 0.583-0.859). These findings indicate that aging, female, fasting glucose ≥ 7.0 mmol/L, smoking and low physical activity levels all increase the risk of sarcopenia, while increased body mass index can decrease the risk of sarcopenia. To conclude, the elderly (especially women) should maintain a healthy lifestyle and slightly higher body mass index levels during the aging process, thus reducing the risk of sarcopenia. [ABSTRACT FROM AUTHOR]

To evaluate the association between ATP2B1 gene polymorphisms and skeletal fluorosis, a cross-sectional study was conducted. In China, 962 individuals were recruited, including 342 cases of skeletal fluorosis. Four TP2BA1 polymorphisms (rs2070759, rs12817819, rs17249754, and rs7136259) were analysed. The results suggested that rs17249754 and rs7136259 were associated with skeletal fluorosis. After controlling confounders, the protective effect of GG genotype in rs17249754 was apparent in individuals over 45 years old, female, with urine fluoride concentration below 1.6 mg/L, serum calcium above 2.25 mmol/L or serum phosphorus between 1.1 and 1.3. Heterozygote TC in rs7136259 increased the risk of skeletal fluorosis in subjects who are elderly, female, with urinary fluoride more than 1.6 mg/L, serum calcium more than 2.25 mmol/L and blood phosphorus between 1.1 and 1.3 mmol/L. Four loci were found to be tightly related by linkage disequilibrium analysis, and the frequency of distribution of haplotype GCGT was lower in the skeletal fluorosis group. [ABSTRACT FROM AUTHOR]

Growth is an important trait in aquaculture that is influenced by various factors, among which genetic regulation plays a crucial role. Megalobrama amblycephala, one of the most important freshwater species in China, exhibits wide variations in body mass among individuals of the same age within the same pool. But the molecular mechanisms underlying wide variation in body mass remain unclear. Here, we performed muscle histological and transcriptome analysis of muscle tissues from Fast-Growing (FG) and Slow-Growing (SG) M. amblycephala at the age of 4 months old (4 mo) and 10 months old (10 mo) to elucidate its muscle development and growth mechanism. The muscle histological analysis showed smaller diameter and higher total number of muscle fibers in FG compared to SG at 4 mo, while larger diameter and total number of muscle fibers were detected in FG at 10 mo. The transcriptome analysis of muscle tissue detected 1171 differentially expressed genes (DEGs) between FG and SG at 4 mo, and 718 DEGs between FG and SG at 10 mo. Furthermore, 44 DEGs were consistently up-regulated in FG at both 4 mo and 10 mo. Up-regulated DEGs in FG at 4 mo were mainly enriched in the pathways related to cell proliferation, while down-regulated DEGs were significantly enriched in cell fusion and muscle contraction. Up-regulated DEGs in FG at 10 mo were mainly enriched in the pathways related to cell proliferation and protein synthesis. Therefore, these results provide novel insights into the molecular mechanism of M. amblycephala muscle growth at different stages, and will be of great guiding significance to promote the fast growth of M. amblycephala. [ABSTRACT FROM AUTHOR]

There are many debates regarding the risk factors of surgical site infection (SSI) following posterior cervical surgery in previous studies. And, till now there is no such a study to examine cervical laminoplasty surgery. From January 2011 through October 2021, a total of 405 patients who were treated with unilateral open‐door laminoplasty surgeries were enrolled in this study. We divided the patients into the SSI group and the non‐SSI group and compared their patient‐specific and procedure‐specific factors. Univariate and multiple logistic regression analysis were performed to determine the risk factors. Of the 405 patients, 20 patients had SSI. The rate of SSI found to be 4.93%. There were significant differences between groups in the thicker subcutaneous fat thickness (FT) (p < 0.001), the higher ratio of subcutaneous FT to muscle thickness (MT) (p < 0.001), the higher preoperative Japanese Orthopaedic Association (JOA) Scores (p < 0.003), the decreased preoperative serum albumin (p < 0.001), the more postoperative drainage (p < 0.05) and the longer time of draining (p < 0.001). Logistic regression analysis of these differences showed that the higher ratio of subcutaneous FT/MT, the higher preoperative JOA scores, the decreased preoperative serum albumin and the longer time of draining were significantly related to SSI (p < 0.05). The higher ratio of subcutaneous FT/MT, the higher preoperative JOA scores, the decreased preoperative serum albumin and the longer time of draining are identified as the independent risk factors of SSI in cervical laminoplasty. Identification of these risk factors could be useful in reducing the SSI incidence and patients counselling. [ABSTRACT FROM AUTHOR]

Simple Summary: The inhibition of inflammation is of great importance for porcine growth and development under heat stress, and due to the hot and humid weather in the Hainan province of China, the local pig populations, including Wuzhishan (WZS) minipigs, have developed excellent heat resistance and adaptability. Moreover, the WZS minipig is a perfect animal model for human disease investigation. Therefore, the genetic selection of genes that play roles in both inhibition of inflammation and suppression of growth is beneficial for the conservation and utilization of WZS minipigs. In this study, we analyzed the genetic selection of genes in top genetically different regions in WZS minipigs and four other pig populations using whole genome sequencing, and we found that the HSP genes (HSPD1 and HSPE1) are connected to both inflammation and growth. As a result, this study offers a valuable theoretical basis for the sustainable application of the conservation and utilization of WZS pigs. Wuzhishan (WZS) pigs, which are minipigs native to Hainan Province in China, are characterized by strong resistance to extreme hot temperatures and humidity. The relationship between their immune response and growth still needs to be clarified. In this study, we used whole genome sequencing (WGS) to detect variations within 37 WZS pigs, 32 Large White (LW) pigs, and 22 Xiangxi black (XXB) pigs, and ~2.49 GB of SNPs were obtained. These data were combined with those of two other pig breeds, and it was found that most of the genes detected (354) were located within the distinct genetic regions between WZS pigs and LW pigs. The network that was constructed using these genes represented a center including 12 hub genes, five of which had structural variations (SVs) within their regulatory regions. Furthermore, RNA-seq and RT-qPCR data for 12 genes were primarily consistent in liver, spleen, and LDM tissues. Notably, the expression of HSPs (HSPD1 and HSPE1) was higher while that of most genes involved in the JAK3-STAT pathway were lower in liver tissue of WZS pigs, compared with LW pigs. This likely not only reduced inflammation-related immune response but also impaired their growth. Our findings demonstrated the role of HSPs in the connection between inflammation and growth rate, while also providing the fundamental genetic selection of the adaptability of WZS pigs. [ABSTRACT FROM AUTHOR]

China boasts a rich diversity of indigenous duck species, some of which exhibit desirable economic traits. Here, we generated transcriptome sequencing datasets of breast muscle tissue samples from 1D of four groups: Pekin duck pure breeding group (P), Jinling White duck breeding group (J), P ♂ × J ♀ orthogonal group (PJ) and J ♂ × P ♀ reciprocal-cross group (JP) (n = 3), chosen based on the distinctive characteristics of duck muscle development during the embryonic period. We identified 5053 differentially expressed genes (DEGs) among the four groups. Network prediction analysis showed that ribosome and oxidative phosphorylation-related genes were the most enriched, and muscular protein-related genes were found in the 14-day-old embryonic group. We found that previously characterized functional genes, such as FN1, AGRN, ADNAMST3, APOB and FGF9, were potentially involved in muscle development in 14-day-old embryos. Functional enrichment analysis suggested that genes that participated in molecular function and cell component and key signaling pathways (e.g., hippo, ribosome, oxidative phosphorylation) were significantly enriched in the development of skeletal muscle at 14 days of embryonic age. These results indicate a possible role of muscle metabolism and myoglobin synthesis in skeletal muscle development in both duck parents and hybrids. [ABSTRACT FROM AUTHOR]

Childhood is a critical period for muscle accumulation. Studies in elders have reported that antioxidant vitamins could improve muscle health. However, limited studies have assessed such associations in children. This study included 243 boys and 183 girls. A seventy-nine-item FFQ was used to investigate dietary nutrients intake. Plasma levels of retinol and α -tocopherol were measured using high-performance liquid chromatography with MS. Dual X-ray absorptiometry was used to assess appendicular skeletal muscle mass (ASM) and total body fat. The ASM index (ASMI) and ASMI Z-score were then calculated. Hand grip strength was measured using a Jamar® Plus+ Hand Dynamometer. Fully adjusted multiple linear regression models showed that for each unit increase in plasma retinol content, ASM, ASMI, left HGS and ASMI Z-score increased by 2·43 × 10−3 kg, 1·33 × 10−3 kg/m2, 3·72 × 10−3 kg and 2·45 × 10−3 in girls, respectively (P < 0·001–0·050). ANCOVA revealed a dose–response relationship between tertiles of plasma retinol level and muscle indicators (P trend: 0·001–0·007). The percentage differences between the top and bottom tertiles were 8·38 %, 6·26 %, 13·2 %, 12·1 % and 116 % for ASM, ASMI, left HGS, right HGS and ASMI Z-score in girls, respectively (P diff: 0·005–0·020). No such associations were observed in boys. Plasma α -tocopherol levels were not correlated with muscle indicators in either sex. In conclusion, high circulating retinol levels are positively associated with muscle mass and strength in school-age girls. [ABSTRACT FROM AUTHOR]

Background: Skeletal muscle mass is an essential parameter for diagnosing sarcopenia. The gold standard for assessing skeletal muscle mass is using computed tomography (CT) to measure skeletal muscle area at the third lumbar vertebra (L3) level. This study aims to investigate whether skeletal muscle mass could be evaluated at the first lumbar vertebra (L1) level using images obtained from routine chest CT scans. Methods: Skeletal muscle index (SMI, cm²/m²) and skeletal muscle density (SMD, HU) are commonly used to measure relative muscle mass and the degree of fat infiltration. This study used CT images at the L1 level to measure the skeletal muscle area (SMA, cm²) in 815 subjects from the health examination center. Linear regression analysis was used to explore the association between L1 and L3 measurements. The receiver operating characteristic (ROC) analysis was used to assess the predictive performance of L1 SMI for sarcopenia. The sex-specific cut-off values for low skeletal muscle mass in patients under the age of 60 were determined using the following formula: "mean - 1.28 × standard deviation." A multivariate linear regression model was established. Results: A significantly higher SMI at the L1 level was found in males than in females (43.88 ± 6.33 cm²/m² vs 33.68 ± 5.03 cm²/m²; P < 0.001). There were strong correlations between measures at the L1 and L3 levels in both the total subject and sex-specific analyses. A negative association was found between age and L3 SMI in males (r = -0.231, P = 0.038). Both body mass index (BMI) and body surface area (BSA) were positively associated with L1 SMI in both males and females. A multivariate analysis was used to establish a prediction rule to predict SMI at the L3 level. The assessment of consistency and interchangeability between predicted and actual SMI at the L3 level yielded moderately good results. Considering the significant differences observed between male and female participants, the sex-specific cut-off values of the L1 SMI for defining low skeletal muscle mass were 36.52 cm²/m² in males and 27.29 cm²/m² in females. Conclusions: Based on a population from central China, the correlated indicators obtained at the L1 level from routine chest CT scans may serve as effective surrogate markers for those at the L3 level in assessing overall skeletal muscle mass. [ABSTRACT FROM AUTHOR]

BACKGROUND: Exercise-induced muscle damage accounts for the highest proportion among various sports injury types, and eccentric exercise patterns may be related to the severity of damage. An effective utilization of skeletal muscle eccentric contraction is of great significance to the development of national fitness and sports undertakings in line with the concept of "healthy China." OBJECTIVE: To investigate the influence of different eccentric exercise patterns on the degree of exercise-induced muscle damage. METHODS: A total of 66 male Sprague-Dawley rats were randomly divided into control group (n=6), single eccentric exercise group (n=30), and continuous eccentric exercise group (n=30) which was further divided into five subgroups at 0.5, 24, 48, 120, 168 hours after the last exercise. The expressions of interleukin-6 and tumor necrosis factor-α in the quadriceps femoris were detected by immunohistochemical staining, and the mean absorbance value was measured. Hematoxylin-eosin staining was used to observe the morphological changes of muscle fibers. RESULTS AND CONCLUSION: There were cells with mild cytoplasmic brown staining of interleukin-6 and tumor necrosis factor-α in the control group. In the exercise groups, the expression of interleukin-6 and tumor necrosis factor-α began to increase at 0.5 hours. From 24 to 48 hours, muscle fibers were distorted with disordered arrangement and contours, the extracellular space was enlarged with inflammatory cell infiltration, the degree and range of cytoplasmic brown staining increased to the peak but it decreased at 120 and 168 hours. The mean absorbance values of interleukin-6 and tumor necrosis factor-α in the continuous eccentric exercise group were lower than those in the once eccentric exercise group at 48, 120, and 168 hours (P < 0.05). The recovery time of morphological structure of the skeletal muscle stained by hematoxylin-eosin was different in the continuous eccentric exercise group and once eccentric exercise group, which was 120 and 168 hours respectively. Results from the two-way repeated measure analysis of variance showed that the mean absorbance values of interleukin-6 and tumor necrosis factor-α were significantly correlated with exercise patterns and time points, and there was an interaction between the exercise pattern and time, with F values of 3.106 and 13.431, respectively (P=0.020, P < 0.001). To conclude, the degree of exercise-induced muscle damage is related to the eccentric exercise pattern, and the continuous eccentric exercise is better than the once eccentric exercise. [ABSTRACT FROM AUTHOR]

Background: Previous research has linked sarcopenic obesity (SO) to cognitive function; however, the relationship between cognitive performance and SO Alzheimer's disease (AD) patients remains unclear. This study aimed to investigate their relationship in AD patients. Methods: One hundred and twenty mild to moderate AD patients and 56 normal controls were recruited. According to sarcopenia or obesity status, AD patients were classified into subgroups: normal, obesity, sarcopenia, and SO. Body composition, demographics, and sarcopenia parameters were assessed. Cognitive performance was evaluated using neuropsychological scales. Results: Among the 176 participants, the prevalence of SO in the moderate AD group was higher than in the normal control group. The moderate AD group had the lowest appendicular skeletal muscle mass index (ASMI) and the highest percentage of body fat (PBF). Hypertension and diabetes were more prevalent in the SO group than in the normal group among the subgroups. The sarcopenia and SO groups exhibited worse global cognitive function compared to the normal and obesity groups. Partial correlation analysis revealed that ASMI, PBF, and visceral fat area were associated with multiple cognitive domains scores. In logistic regression analysis, after adjusting for confounders, obesity was not found to be associated with AD. However, sarcopenia (odds ratio (OR) = 5.35, 95% CI: 1.27–22.46) and SO (OR = 5.84, 95% CI: 1.26–27.11) were identified as independent risk factors for AD. Conclusions: SO was associated with cognitive dysfunction in AD patients. Moreover, the impact of SO on cognitive decline was greater than that of sarcopenia. Early identification and intervention for SO may have a positive effect on the occurrence and progression of AD. [ABSTRACT FROM AUTHOR]

Pigs are susceptible to cold stress due to the absence of brown fat caused by the partial deletion of uncoupling protein 1 during their evolution. Some local pig breeds in China exhibit potential cold adaptability, but research has primarily focused on fat and intestinal tissues. Skeletal muscle plays a key role in adaptive thermogenesis in mammals, yet the molecular mechanism of cold adaptation in porcine skeletal muscle remains poorly understood. This study investigated the cold adaptability of two pig breeds, Mashen pigs (MS) and Large White pigs (LW), in a four-day cold (4 °C) or normal temperature (25 °C) environment. We recorded phenotypic changes and collected blood and longissimus dorsi muscle for transcriptome sequencing. Finally, the PRSS8 gene was randomly selected for functional exploration in porcine skeletal muscle satellite cells. A decrease in body temperature and body weight in both LW and MS pigs under cold stress, accompanied by increased shivering frequency and respiratory frequency, were observed. However, the MS pigs demonstrated stable physiological homeostasis, indicating a certain level of cold adaptability. The LW pigs primarily responded to cold stress by regulating their heat production and glycolipid energy metabolism. The MS pigs exhibited a distinct response to cold stress, involving the regulation of heat production, energy metabolism pathways, and robust mitochondrial activity, as well as a stronger immune response. Furthermore, the functional exploration of PRSS8 in porcine skeletal muscle satellite cells revealed that it affected cellular energy metabolism and thermogenesis by regulating ERK phosphorylation. These findings shed light on the diverse transcriptional responses of skeletal muscle in LW and MS pigs under cold stress, offering valuable insights into the molecular mechanisms underlying cold adaptation in pigs. [ABSTRACT FROM AUTHOR]

Objectives: Several studies have linked myosteatosis with nonalcoholic fatty liver disease (NAFLD) in individuals with obesity The clinical significance of myosteatosis in individuals with NAFLD in the general population has not been well investigated. Here, we wanted to explore and compare the associations of NAFLD and liver fibrosis with muscle fat content and skeletal muscle mass (SMM) in a relatively large general population in China. Methods: We retrospectively included all participants who underwent abdominal CT scans in our health promotion center between April 2021 and October 2021. Muscle fat content was assessed by abdomen quantitative computed tomography (QCT) scans, and SMM was evaluated by bioelectrical impedance. NAFLD was assessed by ultrasonography. The NAFLD fibrosis score (NFS) and Fibrosis-4 Index (FIB-4) score were calculated to assess liver fibrosis. Results: Compared with participants without NAFLD, patients with NAFLD showed significantly increased intermuscular adipose tissue (IMAT%) (7.40±3.37% vs. 6.76±2.66%, P <0.01). According to a multiple logistic regression model, IMAT% (OR=1.091, 95% CI 1.030–1.155, P=0.003) was only independently correlated with NAFLD in obese participants. Mediation analysis showed that BMI mediated the association between IMAT% and NAFLD. In participants with NAFLD, increased IMAT% was independently associated with an increased intermediate to high risk of advanced fibrosis assessed by the NFS or FIB-4 score after adjusting for multiple potential confounders. However, SMM was only independently correlated with an intermediate to high risk for advanced fibrosis evaluated by the NFS and not by the FIB-4 score. Conclusion: Increased muscle fat content is positively correlated with NAFLD and intermediate to high risk for advanced fibrosis in the general Chinese population. [ABSTRACT FROM AUTHOR]

Background: Studies on prognostic factors for older patients with intra-abdominal sepsis are scarce, and the association between skeletal muscle mass and prognosis among such patients remains unclear. Aims: To develop a nomogram to predict in-hospital mortality among older patients with intra-abdominal sepsis. Methods: Older patients with intra-abdominal sepsis were prospectively recruited. Their demographics, clinical features, laboratory results, abdominal computed tomography-derived muscle mass, and in-hospital mortality were recorded. The predictors of mortality were selected via least absolute shrinkage and selection operator and multivariable logistic regression analyses, and a nomogram was developed. The nomogram was assessed and compared with Sequential Organ Failure Assessment score, Acute Physiology and Chronic Health Evaluation II score, and Simplified Acute Physiology Score II. Results: In total, 464 patients were included, of whom 104 (22.4%) died. Six independent risk factors (skeletal muscle index, cognitive impairment, frailty, heart rate, red blood cell distribution width, and blood urea nitrogen) were incorporated into the nomogram. The Hosmer–Lemeshow goodness-of-fit test and calibration plot revealed a good consistency between the predicted and observed probabilities. The area under the receiver operating characteristic curve was 0.875 (95% confidence interval = 0.838–0.912), which was significantly higher than those of commonly used scoring systems. The decision curve analysis indicated the nomogram had good predictive performance. Discussion: Our nomogram, which is predictive of in-hospital mortality among older patients with intra-abdominal sepsis, incorporates muscle mass, a factor that warrants consideration by clinicians. The model has a high prognostic ability and might be applied in clinical practice after external validation. [ABSTRACT FROM AUTHOR]

Objective To evaluate the diagnostic value of skeletal muscle biopsy in asymptomatic and pauci-symptomatic hyperCKemia. Methods and Results A total of 146 patients with asymptomatic or pauci - symptomatic hyperCKemia diagnosed in Peking University First Hospital from July 2020 to February 2023 were selected, and skeletal muscle biopsy was performed. About 72.60% (106/146) had histological changes, including muscular dystrophy (n = 73), inflammatory or necrotizing myopathy (n = 16), other myopathy (n = 15), and neurogenic skeletal muscle damage (n = 2). The positive rate of pathological diagnosis was 50.68% (74/146), including muscular dystrophy 82.43% (61/74), inflammatory myopathy 8.11% (6/74) and metabolic myopathy 9.46% (7/74). The positive rate of etiological diagnosis was 85.62% (125/146), including muscular dystrophy 67.20% (84/125), inflammatory myopathy 13.60% (17/125), metabolic myopathy 7.20% (9/125) and other causes 12% (15/125). Compared with different subgroups, the proportion of pathological changes ((χ² = 14.043, P = 0.000; (χ² = 12.740, P = 0.000), the positive rate of pathological diagnosis ((χ² = 10.641, P = 0.001; (χ² = 25.530, P = 0.000) and etiological diagnosis (Fisher's exact probability: P = 0.001; χ² = 10.811, P = 0.001) in the significantly elevated creatine kinase (CK) level group and the adolescent group was significantly higher than those in the mildly elevated CK level group and the adult group. The positive rate of pathological diagnosis in the asymptomatic group was higher than the pauci-symptomatic group (χ² = 4.792, P = 0.029). There were significant differences in the etiological ratio between the mildly elevated CK level group and the significantly elevated CK level group (Fisher's exact probability: P = 0.000), the adolescent group and the adult group (χ² = 86.149, P = 0.000), and the asymptomatic group and the pauci - symptomatic group (χ² = 20.608, P = 0.000). Conclusions Skeletal muscle biopsy was important in etiological diagnosis of asymptomatic and pauci-symptomatic hyperCKemia. Muscular dystrophy is a common cause of asymptomatic and pauci-symptomatic hyperCKemia. [ABSTRACT FROM AUTHOR]

Purpose: Physical activity (PA) is likely to be the most important modifiable factor in skeletal muscle development. However, the influence of PA on the skeletal muscle of preschool children has not been thoroughly investigated. The main objective of this study was to quantitatively measure PA, and then, to assess whether associations exist between site-specific muscle changes and PA in relation to sex and weight statuses in preschool children aged 3 to 4 years. Methods: A total of 86 healthy preschool children, aged 3–4 years, were instructed to wear an accelerometer for seven consecutive days. The number of steps taken daily, and minutes spent in moderate–vigorous PA (MVPA) and total PA (TPA) were recorded. Muscle thickness was measured by B-mode ultrasonography using a 5–18 MHz scanning head. Muscle thickness was measured at seven sites: the lateral forearm, upper arm, abdomen, anterior and posterior thigh, and anterior and posterior lower leg. Results: There was no significant difference between boys and girls in terms of MVPA and TPA on weekdays and weekends. According to the linear regression models, after adjusting for daylight duration, the muscle of the posterior thigh was significantly positively associated (p < 0.05) with daily steps and MVPA on weekdays for boys and girls, respectively. Conclusions: We found that the muscle thickness of the posterior thigh in preschool children was significantly positively associated with PA, as measured by daily steps and MVPA. We suggest that for the overall health and well-being of preschool children, the levels of PA should be maintained and/or increased, and preferably transformed into a regular part of daily living. [ABSTRACT FROM AUTHOR]

• Low muscle mass is a novel and effective predictive marker for incidence of cardiovascular events in a general population. • This relationship is independent of multiple well-established CVD risk factors such as smoking, diabetes, hypertension, and dyslipidemia. • Low muscle mass strengthens predicting future cardiovascular events over traditional risk score, especially among people with a moderate-to-high risk. We aimed to explore the association between skeletal muscle mass and cardiovascular events, and its additional value on the assessment of cardiovascular diseases (CVD) over traditional risk scores. The study included 1365 community-based participants aged over 50 years and free of CVDs at baseline. Participants completed detailed assessments at baseline and received a follow-up assessment in 2021–2022 via phone calls or electronic medical records. Skeletal muscle mass was measured using an automatic bioelectric analyzer. Predicted probabilities of 10-year atherosclerotic cardiovascular disease (ASCVD) risk were estimated individually with the China-PAR equation. After a mean follow-up of 7.6 years, 144 cardiovascular events were identified. The fully-adjusted hazard ratios (HRs) of cardiovascular events were 0.93 (0.88–0.98) and 1.08 (1.04–1.12) for skeletal muscle mass and predicted 10-year risk, respectively. Among participants over 60 years and with two or more risk factors, cardiovascular events risk increased progressively with each decreasing skeletal muscle tertile. Receiver operating characteristic curves showed that the C-statistic of predicting cardiovascular events for a 10-year risk assessment was slightly increased after adding skeletal muscle mass. The categorical net reclassification improvement (NRI) showed a 56.7% increase in the reclassification. The continuous NRI and integrated discrimination improvement increased as well. Participants with low skeletal muscle mass were more likely to have cardiovascular events. Low muscle mass improved the predictive power of CVD incidence over the original risk score, indicating that muscle mass could be a valuable parameter and a declining value needed early detection in the population. [ABSTRACT FROM AUTHOR]

The Huai pig is a well-known indigenous pig breed in China. The main advantages of Huai pigs over Western commercial pig breeds include a high intramuscular fat (IMF) content and good meat quality. There are significant differences in the meat quality traits of the same muscle part or different muscle parts of the same variety. To investigate the potential genetic mechanism underlying the meat quality differences in different pig breeds or muscle groups, longissimus dorsi (LD), psoas major (PM), and biceps femoris (BF) muscle tissues were collected from two pig breeds (Huai and Duroc). There were significant differences in meat quality traits and amino acid content. We assessed the muscle transcriptomic profiles using high-throughput RNA sequencing. The IMF content in the LD, PM, and BF muscles of Huai pigs was significantly higher than that in Duroc pigs (p < 0.05). Similarly, the content of flavor amino acids in the three muscle groups was significantly higher in Huai pigs than that in Duroc pigs (p < 0.05). We identified 175, 110, and 86 differentially expressed genes (DEGs) between the LD, PM, and BF muscles of the Huai and Duroc pigs, respectively. The DEGs of the different pig breeds and muscle regions were significantly enriched in the biological processes and signaling pathways related to muscle fiber type, IMF deposition, lipid metabolism, PPAR signaling, cAMP signaling, amino acid metabolism, and ECM–receptor interaction. Our findings might help improve pork yield by using the obtained DEGs for marker-assisted selection and providing a theoretical reference for evaluating and improving pork quality. [ABSTRACT FROM AUTHOR]

Objective: Research on muscularity‐oriented disordered eating has grown in recent years. However, the bulk of this research has focused on men and Western populations. Limited research is available in non‐Western populations of women (e.g., China) which is likely due to the lack of valid instruments in these populations. Thus, the current study aimed to describe the validity and reliability of the Muscularity‐Oriented Eating Test (MOET) in Chinese women. Method: Two online surveys (survey one: n = 599, Mage = 29.49, SD = 7.36; survey two: n = 201, Mage = 28.42, SD = 7.76) were conducted to explore the psychometric properties of the MOET in Chinese women. In survey one, the factor structure of the MOET was examined via exploratory and confirmatory factor analyses (EFA and CFA). Internal consistency reliability and convergent and incremental validity of the MOET were also assessed. In survey two, test–retest reliability across a 2‐week interval was examined. Results: EFA and CFA provided support for the unidimensional factor structure of the MOET in Chinese adult women. The MOET presented good internal consistency and test–retest reliability and convergent validity via large, positive associations with theoretically related constructs (e.g., thinness‐oriented disordered eating, drive for muscularity, and psychosocial impairment). Finally, muscularity‐oriented disordered eating described unique variance in psychosocial impairment, providing support for the incremental validity of the MOET. Discussion: The sound psychometric structure of the MOET was supported in Chinese women. Continued research is needed to describe muscularity‐oriented disordered eating in Chinese women to contribute to this significant gap in the literature. Public Significance: The Muscularity‐Oriented Eating Test (MOET) is a measure specifically developed for assessing muscularity‐oriented disordered eating. This study examined the validity and reliability of the MOET in Chinese women. The results showed that the MOET had sound validity and reliability in Chinese women. Thus, the MOET is a valuable tool for advancing the understanding of the muscularity‐oriented disordered eating of women from the Chinese context. [ABSTRACT FROM AUTHOR]

Objectives: Muscle health is essential for children's physical development and future health. PPARGC1A gene encode the peroxisome proliferator-activated receptor coactivator 1α which coactivates transcription factors that control mediating skeletal muscle fiber type conversion and skeletal muscle fiber formation. The PPARGC1A rs8192678 Gly/Ser (Gly482Ser) polymorphism was associated with the regulation of skeletal muscle fibre type. This paper aims to explore the association between the PPARGC1A rs8192678 (Gly482Ser) polymorphism and muscle fitness in Chinese schoolchildren. Methods: We detected the distribution of the PPARGC1A rs8192678 (Gly482Ser) polymorphism by DNA typing of saliva samples from untrained Southern Chinese Han children aged 7–12 years. Considering that muscle studies in children cannot use invasive sampling, we analyzed the association between alleles and genotypes with high validity tests of muscle fitness assesment in children(handgrip strength, standing long jump, sit-ups and push-ups). Results: The results showed no significant differences in height, weight or body mass index between the sexes. The grip strength indicators were correlated with age in boys and height and weight in girls. Sit-ups were significantly higher in girls with the PPARGC1A Gly/Gly genotype than in boys, and handgrip strength and standing long jump were significantly lower in girls with the PPARGC1A rs8192678 (Gly482Ser) genotype than in boys. Genetic model analysis showed that the Gly482 allele had a dominant genetic effect on the Gly482 allele is hypothesized to influence the expression of type I fibers in skeletal muscle in girls, while the Ser482 allele affects on type II fibers in girls. The two alleles had little genetic effect on boys. Conclusions: The results suggested the possible association of the PPARGC1A rs8192678 (Gly482Ser) polymorphism on myofibril type-related phenotypes in Han Chinese children in southern China, with a particular impact on girls. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to construct a formula to predict L3 skeletal muscle cross‐sectional area (CSA) from C3 CSA and to select the cutoff values to evaluate the nutritional status in OSCC. Materials and Methods: A total of 220 OSCC patients in Nanfang Hospital were divided into two groups: the training set (n = 100) and the validation set (n = 120). Patients in the training set were performed the preoperative whole‐body positron emission tomography‐computed tomography (PET/CT) scans, and patients in the validation set received preoperative head‐and‐neck computed tomography (CT) scans. C3 CSA and L3 CSA were delineated. The predictive formula was established, and the gender‐specific thresholds of malnutrition were obtained by X‐tile software in training set. Finally, the formula and cutoff values were validated. Results: The predictive formula was successfully established. The gender‐specific cutoff values for L3 SMI were 55.0 cm2/m2 for men and 36.6 cm2/m2 for women. There were no differences between the overall survival (OS) of patients diagnosed with malnutrition and that of patients who are not malnutrition. Conclusions: Our studies reveal that the L3 CSA could be calculated by C3 CSA conveniently with our formula in OSCC, which allowed us to assess malnutrition with head‐and‐neck CT image. However, there is no direct connection found between malnutrition and OS in OSCC. Hence, further studies with a larger sample size may be required. [ABSTRACT FROM AUTHOR]

Background: It has been reported that the harvested hamstring tendon for autograft could be regenerated with well-oriented fibers and uniformly distributed spindle-shaped cells after removal. However, which cell type might participate in the repair process remains unknown. Purpose: To investigate the tenogenic differentiation potential of human muscle–derived cells (MDCs) both in vitro and in vivo. Study Design: Controlled laboratory study. Methods: Primary human MDCs and tenocytes were isolated from discarded materials during a peroneus longus tendon–harvesting procedure. Expression of tenogenic genes were evaluated and compared among MDCs, MDCs with tenogenic induction, and tenocytes. RNA sequencing was performed to evaluate the expression profile of differentiated MDCs. Human MDCs were implanted in a tendon injury model to investigate the in vivo tenogenic differentiation potential. Histologic and functional analyses were performed to evaluate the function of MDCs for tendon repair. Results: The relative expression levels (in fold change) of tenogenic genes Col I, MKX, SCX, THBS4, and TNC in MDCs were significantly upregulated 11.5 ± 1.3, 957.1 ± 63.7, 19.1 ± 2.8, 61.9 ± 4.8, and 10.2 ± 2.8 after tenogenic induction, respectively. The expression profile of tenogenically differentiated MDCs was much closer to primary tenocytes. Activation of TGF-β/Smad3 signaling significantly promoted the tenogenic differentiation ability of MDCs. Transplanted human MDCs were identified in regenerated tendon and expressed tenogenic genes. As for biomechanical properties, the failure loads in the Matrigel, transplantation, and uninjured groups were 7.2 ± 0.5, 11.6 ± 0.3, and 13.9 ± 0.7 N, while the stiffness values were 4.4 ± 1.3 × 103, 7.6 ± 0.8 × 103, and 10.9 ± 1.1 × 103 N/m. Plantarflexion force, histologic morphology, and motor function were also significantly improved after MDC transplantation in a tendon injury model. Conclusion: There exist cells with tenogenic differentiation potential in human skeletal muscles. Activation of TGF-β/Smad3 signaling plays an important role in tenogenic differentiation for human MDCs. Human MDCs contribute to structural and functional repair for the injured tendon. MDCs are a potential cell source to participate in the repair process after tendon injury. Clinical Relevance: The MDCs could be a promising cell source to repair tendon injury. [ABSTRACT FROM AUTHOR]

Simple Summary: Research into the genetic mechanisms of skeletal muscle development in ducks is of great significance to the breeding and industrialization of indigenous ducks in China. This study examined the crucial candidates during two developmental stages of duck embryonic breast muscles by circular RNA sequencing. There were 16,622 circular RNAs detected between embryonic day 13 (E13) and embryonic day 19 (E19), of which 260 showed differential expression. Additionally, we examined the protein–protein interaction (PPI) with the parental genes of the differentially expressed circular RNAs, as well as the enriched GO terms and KEGG pathways. In addition, we selected one circular transcript of the growth arrest-specific gene 2 (GAS2), or circGAS2-2, to perform functional validations in duck embryonic myoblasts. The results showed that circGAS2-2 accelerated cell cycling and promoted the proliferation of myoblasts. Our results supplement the duck circular RNA database and demonstrate that circular RNAs are abundantly and differentially expressed during duck skeletal muscle development. Circular RNAs are widespread in various species and have important roles in myogenesis. However, the circular RNAs involved in breast muscle development in ducks have not yet been studied. Here, to identify circular RNAs during duck skeletal muscle development, three pectorales from Shan Ma ducks at E13 and E19, which represent undifferentiated and differentiated myoblasts, respectively, were collected and subjected to RNA sequencing. A total of 16,622 circular RNAs were identified, of which approximately 80% were exonic circular RNAs and 260 were markedly differentially expressed between E19 and E13. The parental genes of the differentially expressed circular RNAs were significantly enriched in muscle-related biological processes. Moreover, we found that the overexpression of circGAS2-2 promoted cell cycle progression and increased the proliferation viability of duck primary myoblasts; conversely, knockdown of circGAS2-2 retarded the cell cycle and reduced the proliferation viability of myoblasts. Taken together, our results demonstrate that circular RNAs are widespread and variously expressed during the development of duck skeletal muscle and that circGAS2-2 is involved in the regulation of myogenesis. [ABSTRACT FROM AUTHOR]

To evaluate the long-term outcomes of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation of uterine fibroids classified by T2-weighted magnetic resonance imaging (T2WI-MRI). The data of 1427 premenopausal women with symptomatic uterine fibroids who underwent USgHIFU at four teaching hospitals in China were analyzed retrospectively. The uterine fibroids were classified based on their T2WI-MRI signal intensities relative to that of skeletal muscle, myometrium and endometrium as: hypointense, isointense, heterogeneous hyperintense fibroids (HHF), slightly HHF (sHHF) and markedly HHF (mHHF), respectively. The rates of symptom relief and reintervention post-USgHIFU ablation were compared between the classified groups. A total of 1303 patients were followed up for 44 (40, 49) months. The symptom relief rate of the hypointense and isointense fibroids was 83.3% and 79.5%, respectively, which were significantly higher (p <.05) compared to that of HHF, sHHF and mHHF (58.3%, 44.2% and 60.4%), respectively. sHHF had the lowest symptom relief rate (p <.05). The cumulative reintervention rate for hypointense, isointense, HHF, sHHF and mHHF types were 8.8%, 10.8%, 21.4%, 39.9% and 19.8%, respectively. The reintervention rate of hypointense/isointense fibroids was significantly lower than that of HHF/mHHF/sHHF (p <.01), while sHHF had the highest re-intervention rate (p <.01). Thus, reintervention rate is inversely correlated to the rate of symptom relief. USgHIFU ablation is effective for hypointense, isointense, HHF and mHHF with acceptable long-term follow-up outcomes. However, sHHF is associated with a higher reintervention rate. [ABSTRACT FROM AUTHOR]

The Duroc pig originated in the United States and is a typical lean-meat pig. The breed grows fast, and the body size is large, but the meat quality is poor. The Luchuan pig is one of eight excellent local breeds in China; it has tender meat but is small in size. To study the factors that determine growth, we selected the longissimus dorsi muscle of Luchuan and Duroc pigs for transcriptome sequencing. The results of the transcriptome showed that 3682 genes were differentially expressed (DEGs) in the longissimus dorsi muscle of Duroc and Luchuan pigs. We screened out genes related to muscle development and selected the MYL2 (Myosin light chain-2) gene to perform preliminary research. Gene Ontology (GO) enrichment of biological functions and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the gene products were mainly involved in the Akt/FoxO signaling pathway, fatty acid metabolism, arachidonic acid metabolism and glycine, serine and threonine metabolism. Such pathways contributed to skeletal muscle growth, fatty acid metabolism and intramuscular fat deposition. These results provide insight into the mechanisms underlying the formation of skeletal muscle and provide candidate genes to improve growth traits, as well as contribute to improving the growth and development traits of pigs through molecular breeding. [ABSTRACT FROM AUTHOR]

Tengchong snow, which has white feathers and black meat, is one of the most important black-bone chicken breeds and a genetic treasure of black food in China. Although the black meat traits are dominant, there are some chickens with white meat traits born in the process of folk selection and breeding. The purpose of this study was to compare the differences in skeletal muscle development between Tengchong snow black meat chickens (BS) and white meat chickens (WS), as well as whether excessive melanin deposition has an effect on skeletal muscle development. The BS and WS groups were selected to determine their muscle development difference at stages of 1, 7, 14, 21, and 42 days, using histological stain methods to analyze the development and composing type of breast and leg muscle fibers, as well as the count of melanin in BS muscle fibers. Finally, we were validated key candidate genes associated with muscle development and melanin synthesis. The results showed that BS breast muscle development was inhibited at 7, 14, and 21 days, while the leg muscle was inhibited at 7, 14, 21, and 42 days, compared to WS. Melanin deposition was present in a temporal migration pattern and was greater in the leg muscles than in the breast muscles, and it focused around blood vessels, as well as the epithelium, perimysium, endomysium, and connective tissue. Additionally, melanin produced an inhibitory effect similar to MSTN during skeletal muscle fiber development, and the inhibition was strongest at the stage of melanin entry between muscle fibers, but the precise mechanisms need to be confirmed. This study revealed that melanin has an inhibitory effect on the early development of skeletal muscle, which will provide new insights into the role of melanin in the black-boned chicken and theoretical references for the future conservation and utilization of black-boned chicken. [ABSTRACT FROM AUTHOR]

Background the effects regarding n-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on sarcopenia have been explored by several clinical trials. Nonetheless, the use of n-3 PUFA for improving body composition, muscle strength and physical performance in older people is conflicting. Objectives our aim was to perform a randomised, double-blind, controlled trial to evaluate the effects of 6-month n-3 PUFA supplementation on body composition, muscle strength and physical performance in older Chinese people. Methods in this double-blind, placebo-controlled trial, 200 eligible subjects were randomly assigned to receive 4 g/day fish oil capsules (1.34 g eicosapentaenoic [EPA] + 1.07 docosahexaenoic [DHA]) or 4 g/day corn oil capsules (EPA + DHA <0.05 g) for 6 months. The primary outcomes were the changes of body composition, muscle strength (hand grip strength) and physical performance (Timed Up and Go time). Secondary outcomes were the changes in serum lipid profiles. Results compared with control group, fish oil-derived n-3 PUFA supplementation resulted in significant increases in thigh circumference (interaction time × group effect P  < 0.001), total skeletal muscle mass (interaction time × group effect P  < 0.001) and appendicular skeletal muscle mass (interaction time × group effect P  < 0.001); the differences were still significant even after height correction. Muscle strength and physical performance including hand grip strength (interaction time × group effect P  < 0.001) and Timed Up and Go time (interaction time × group effect P  < 0.001) were also improved after a 6-month fish oil-derived n-3 PUFA intervention. In terms of serum lipid profiles, fish oil-derived n-3 PUFA supplementation could significantly reduce serum level of triglyceride (interaction time × group effect P  = 0.012) and increase high density lipoprotein cholesterol (interaction time × group effect P  < 0.001); while no significant improvement was found in serum concentrations of total cholesterol (interaction time × group effect P  = 0.413) and low density lipoprotein cholesterol (interaction time × group effect P  = 0.089). Conclusions our present trial demonstrated that a 6-month fish oil-derived n-3 PUFA supplementation could beneficially affect the body composition, muscle strength, physical performance and serum lipid profiles in older people, which could be into considerations when making strategies aiming to the primary prevention of sarcopenia. [ABSTRACT FROM AUTHOR]

Objective: To explore the dynamic changes in the body composition during chemotherapy in patients with gastrointestinal malignancies in the context of active nutrition intervention. Methods: Patients with gastrointestinal malignancies receiving first-line chemotherapy in the Department of Medical Oncology of Ordos Central Hospital from September 2019 to January 2022 were included in this study. The Nutritional Risk Screening form 2002, Patient-Generated Subjective Global Assessment form, bioelectrical impedance analysis, and dynamic changes in L3 skeletal muscle index (SMI) (L3SMI) were assessed at baseline and after chemotherapy. The recommended protocol of the Nutrition Guidelines for Cancer Patients in China 2020 was adopted as the active nutrition intervention. Chemotherapy-related toxic adverse reactions and the degree of toxicity were recorded with the adoption of the Common Terminology Criteria for Adverse Events version 4.0 by the National Institutes of Health. The type of toxicity Chemotherapy-Induced Nauseaand Vomiting(CINV) and hematological. Results: Fifty cases were enrolled in the study, and 38 cases completed the dynamic follow-ups. The average follow-up time was 125.63 d. In the context of active nutrition intervention, the prevalence of sarcopenia decreased from 26.3% before chemotherapy to 21.1% after chemotherapy. The average L3SMI decreased from 38.77 cm2 /m2 to 38.04 cm2 /m2, with a reduction of 1.41% ± 8.49% (P = 0.177). The SMI remained stable or increased in 57.9% (22/38) of patients. The benefit of active nutrition intervention was greater in the sarcopenic group than in the non-sarcopenic group (P = 0.033). There was an increased incidence of chemotherapy-related toxic adverse reactions of ≥ grade 3 during chemotherapy in the sarcopenic group compared with the muscle retention/gain group (P = 0.089).Conclusion: Active nutrition intervention might decrease the degree of reduction of L3SMI and the incidence of sarcopenia in patients with gastrointestinal tumors and raise the proportion of patients with stable or increased SMI during chemotherapy. [ABSTRACT FROM AUTHOR]

In this study, a D‐galactose‐induced aging mouse model was established, and Syringa oblata Lindl. extract (SOLE) was administered orally to observe the effect and mechanism of SOLE on the running ability of aging mice. The role of SOLE was evaluated by H&E histopathological observation, detection of serum biochemical indices, and detection of mRNA expression levels by qPCR experiments. The experimental results showed that SOLE could increase the exhaustive running time of aging mice and reduce the oxidative aging of the liver and kidney. At the same time, the levels of BUN, lactic acid, GOT, GPT, MDA, iNOS, and TNF‐α in the serum of the mice were decreased, and the relative mRNA expression levels of nNOS, iNOS, TNF‐α and syncytin‐1 in the liver tissue and skeletal muscle tissue of the mice were downregulated. In addition, it increased the levels of CAT, GSH‐Px, and T‐SOD in mouse serum and upregulated the relative mRNA expression of Cu/Zn‐SOD, Mn‐SOD, and CAT in mouse liver tissue and muscle tissue. The analysis results showed that SOLE mainly contained rutin, isoquercitrin, ferulic acid, dihydroquercetin, and quercitrin. In summary, SOLE can enhance the running ability and exercise ability of aging mice and slow down aging. Practical applications: Clove is used as health tea or traditional Chinese medicine in China, but there is no relevant research and application on the improvement of human exercise ability. This study found this new function of clove, which accumulated a theoretical basis for further popularizing its application. [ABSTRACT FROM AUTHOR]

The increased sensitivity of pigs to ambient temperature is due to today's intensive farming. Frequent climate disasters increase the pressure on healthy pig farming. Min pigs are an indigenous pig breed in China with desirable cold resistance characteristics, and hence are ideal for obtaining cold-resistant pig breeds. Therefore, it is important to discover the molecular mechanisms that are activated in response to cold stress in the Min pig. Here, we conducted a transcriptomic analysis of the skeletal muscle of Min pigs under chronic low-temperature acclimation (group A) and acute short cold stress (group B). Cold exposure caused more genes to be upregulated. Totals of 125 and 96 differentially expressed genes (DEGs) were generated from groups A and B. Sixteen common upregulated DEGs were screened; these were concentrated in oxidative stress (SRXN1, MAFF), immune and inflammatory responses (ITPKC, AREG, MMP25, FOSL1), the nervous system (RETREG1, GADD45A, RCAN1), lipid metabolism (LRP11, LIPG, ITGA5, AMPD2), solute transport (SLC19A2, SLC28A1, SLCO4A1), and fertility (HBEGF). There were 102 and 73 genes that were specifically differentially expressed in groups A and B, respectively. The altered mRNAs were enriched in immune, endocrine, and cancer pathways. There were 186 and 91 differentially expressed lncRNAs generated from groups A and B. Analysis of the target genes suggested that they may be involved in regulating the MAPK signaling pathway for resistance to cold. The results of this study provide a comprehensive overview of cold exposure–induced transcriptional patterns in skeletal muscle of the Min pig. These results can guide future molecular studies of cold stress response in pigs for improving cold tolerance as a goal in breeding programs. [ABSTRACT FROM AUTHOR]

Background Previous studies have presented inconsistent results on the relationship between serum uric acid and skeletal muscle mass (SMM). We aimed to explore whether a higher serum uric acid level was associated with low SMM in the Chinese population. Methods We performed a cross-sectional analysis of 6595 subjects aged 45 years or older. They were tested for fasting blood glucose, total cholesterol, triglycerides, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, uric acid, blood urea nitrogen, creatinine, and estimated glomerular filtration rate. SMM was accessed by dual-energy x-ray absorptiometry using two approaches: weight-adjusted appendicular skeletal muscle mass (ASM)% and ASM/BMI (body mass index (kg/m2)). Low SMM was defined as a cut-off point of ASM/BMI<0.789 for men and<0.512 for women. Results Compared with their normal group, patients with hyperuricemia had lower ASM% (29.33±2.33 vs 30.03±2.34 for males and 24.71±1.99 vs 25.19±2.07 for females, P<0.01) and ASM/BMI (0.83±0.10 vs 0.85±0.10 for male and 0.60±0.07 vs 0.62±0.07 for female), with a higher prevalence of the associated low SMM in both sexes (35.2 vs 26.5% for male and 10.5 vs 5.9% for female, P<0.01). Pearson analysis showed that ASM% and ASM/BMI were negatively correlated with SUA (male: ASM/BMI, r=−0.097, ASM%, r=−0.146; female: ASM/BMI, r=−0.151, ASM%, r=−0.157; all P<0.001). Logistic regression analysis showed a positive association of hyperuricemia with adjusted risk of low SMM association. Conclusions In a middle-aged and elderly Chinese population, hyperuricemia is independently and positively associated with low SMM and can vary by age and gender. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the contribution of body composition including skeletal muscle mass (SMM) and body fat mass (BFM) to longitudinal growth among children and adolescents aged 6-11 years old. Methods: This cohort study was conducted from the annual health examination between 2019 and 2020. Annual height gain and weight gain and changes in SMM and BFM were calculated and compared between sexes, different nutritional status, and growth curve shifting mode. Spearman analyses and multiple linear regression analysis were performed to identify the impact of SMM, BFM, or body mass index (BMI) on height gain. Results: Of the 584 subjects, the annual height gains of boys (4.76 cm in the 6-9-year group and 4.63 cm in the 10-11-year group) were significantly lower than those of girls (5.48 and 5.74 cm, respectively). Spearman analysis showed that SMM gain and height gain were positively and significantly correlated in each examination of all children (r = 0.535 for boys and 0.734 for girls, p < 0.001). Conversely, BFM and height gains were negatively (r = -0.5240 for boys and -0.232 for girls, p < 0.001) correlated. Multiple linear regression analysis identified SMM gain as an independent predictor (95% CI: 1.20,1.44) of height gain after adjusting for age, gender, BMI, BFM gain, and percentage of body fat (PBF). Conclusion: SMM gains, rather than BFM gains, were associated with height gains in children and adolescents aged 6-11 years. Monitoring SMM changes in routine healthcare might motivate children and adolescents to achieve dietary and exercise recommendations, thereby growing taller without gaining excessive weight. [ABSTRACT FROM AUTHOR]

Epinephelus coioides is a fish species with high economic value due to its delicious meat, high protein content, and rich fatty acid nutrition. It has become a high-economic fish in southern parts of China and some other Southeast Asian countries. In this study, the myostatin nucleic acid vaccine was constructed and used to immunize E. coioides. The results from body length and weight measurements indicated the myostatin nucleic acid vaccine promoted E. coioides growth performance by increasing muscle fiber size. The results from RT-qPCR analysis showed that myostatin nucleic acid vaccine upregulated the expression of myod, myog and p21 mRNA, downregulated the expression of smad3 and mrf4 mRNA. This preliminary study is the first report that explored the role of myostatin in E. coioides and showed positive effects of autologous nucleic acid vaccine on the muscle growth of E. coioides. Further experiments with increased numbers of animals and different doses are needed for its application to E. coiodes aquaculture production. [ABSTRACT FROM AUTHOR]

Introduction: Body composition is closely related to metabolic health status. Visceral adipose tissue (VAT) dysfunction contributes to metabolic syndrome. However, results regarding subcutaneous adipose tissue (SAT) and skeletal muscle are controversial. We aimed to determine the association of indices of body composition with abnormal metabolic phenotype in China. Methods: A total of 3, 954 subjects (age 50.2 ± 11.7 years) with body mass index (BMI) more than 18.5 kg/m2 from Pinggu Metabolic Disease Study were analyzed. Quantitative computed tomography (QCT) was performed to measure total adipose tissue (TAT), VAT, SAT area, and lumbar skeletal muscle area (SMA). Participants were divided into six groups on the basis of BMI category (normal weight/overweight/obesity) and metabolic status (healthy/unhealthy), as defined by the presence or absence of components of the metabolic syndrome by Chinese Diabetes Society criteria. Results: 63.4%, 39.5%, and 23.3% participants were classified as metabolically healthy phenotype in individuals with normal weight, overweight and obese, respectively. Individuals in the highest TAT, VAT, and VAT/TAT ratio category had higher risk of being metabolically unhealthy than individuals in the lowest group (all p <0.01). While, risk for metabolically unhealthy was reduced significantly in the highest SMA/TAT ratio category when compared with the lowest category in individuals with normal wight and overweight (both p <0.05). Risk for metabolically unhealthy was reduced significantly in the highest SAT category when compared with the lowest category (OR=0.555, 95%CI: 0.360-0.856, p =0.008) in individuals with obese after adjustment for age, sex and BMI. However, skeletal muscle index (SMI) showed no significant association with the metabolically healthy status in different BMI categories (p >0.05). The VAT and VAT/TAT ratio were better diagnostic values of indicators to differentiate metabolically unhealthy subjects from controls compared with other indicators, such as TAT, SAT, SMI, SMA/TAT ratio. Conclusions: Higher visceral adipose tissue was closely associated with metabolically unhealthy phenotype in Chinese adults. Subcutaneous adipose tissue might be a protective factor for metabolic health status only in obese individuals. [ABSTRACT FROM AUTHOR]

Study Design: A randomized controlled trial.Objective: To evaluate the effects of inelastic and elastic lumbosacral orthoses (LSOs) on the prevention of low back pain (LBP) in healthy nurses.Summary Of Background Data: Over 80% of people experience LBP during their lifetime. LSOs, as a device used to maintain lumbar stability, were widely used in LBP management. The effects of inelastic LSOs (iLSOs) and elastic LSOs (eLSOs) on the prevention of LBP are controversial.Methods: A randomized clinical trial recruiting healthy nurses was conducted from November 2011 to June 2013 at a tertiary hospital in China. A total of 300 eligible participants aged 20 to 25 years were randomly assigned to iLSO, eLSO, or control groups. The intervention period was 6 months, and follow-ups were continued for an additional 6 months. Participants in both iLSO and eLSO groups were required to wear LSOs daily. Outcomes included the incidence of LBP, changes in trunk muscle endurance, and spinal range of motion assessed at baseline, 6months, and 12 months from the starting date. The incidence of LBP among groups was analyzed by ANOVA. Wilcoxon rank-sum test, Kruskal-Wallis H test, etc. were used for secondary outcomes comparison across groups.Results: Two hundred seventy-eight out of 300 participants (92.7%) completed the trial. No statistically significant differences were observed in LBP incidence among the three groups. No difference was observed in abdominal/back muscle endurance among groups at 6 months. In secondary outcome analysis regarding spinal range of motion, flexion and extension improved in iLSO groups at 12 months compared with that at baseline (flexion, P  = 0.01; extension, P  = 0.01), whereas only extension motion improved at 12 months in the eLSO group (P  = 0.00).Conclusions: Six-month wearing of LSO showed neither a significant difference in preventing LBP nor causing adverse effects to participants.Level of Evidence: 1. [ABSTRACT FROM AUTHOR]

The snowboarding project has the characteristics of high risk and high technical level. The current publicity level is not high, and the number of participants is also very limited. Another potential advantage medal breakthrough project that is expected to be achieved in the Winter Olympics has received a lot of attention, creating favorable opportunities for the promotion and development of this project in China. The event requires good special physical support, skeletal muscle contraction is the body to produce motor function, and special physical training and recovery are key factors for athletes to obtain excellent results in the competition. This article is aimed at performing ultrasonic quantitative analysis on the skeletal muscles of skiers after exercise based on artificial intelligence and complex networks and at studying the skeletal muscle conditions of snowboarders after exercise, so as to provide a certain theoretical basis for coaches in future scientific training. Based on a large amount of literature, this paper uses variational optical flow calculation and split Bregman method to solve the typical HS model, L1-L2 model, and L1-high-order model, respectively, and uses the motion estimation method to describe the movement of muscles. An experiment was designed to collect ultrasound images of the gastrocnemius and quadriceps muscles during contraction. In addition, a motion target positioning algorithm was used to obtain some motion parameters, which provided direct help for athletes in rationally arranging training load and scientific training. The experimental results in this paper show that the muscle motion features extracted from the ultrasound sequence images can quantitatively express a lot of important information about the skeletal muscle motion form and function and have potential practical application value. And the different invariants of each type of ski trajectory vary greatly, floating between 1.5429 and 7.6759. [ABSTRACT FROM AUTHOR]

Purpose: The effects of short-term blood flow restriction (BFR) exercise on muscle blood flow perfusion and performance during high-intensity exercise were determined in elite para-alpine standing skiers to assess whether this would be an effective training regimen for elite athletes with disabilities. Methods : Nine national-level para-alpine standing skiers (mean age, 20.67 +/- 1.34 yr; four women) were recruited. Nondominant lower limbs were trained with BFR (eight in final analyses), and dominant lower limbs were trained without BFR (seven in final analyses). The 2-wk protocol included high-load resistance, local muscle endurance (circuit resistance training), and aerobic endurance (stationary cycling) training performed 4 times a week, with BFR during local muscle endurance and aerobic endurance sessions. Muscle strength was measured by maximal voluntary isometric contraction (MVIC) in the knee extensors; microcirculatory blood perfusion (MBP), by laser Doppler blood flow; and muscle strength and endurance, by the total amount of work (TW) performed during high-intensity centrifugal and concentric contractions. Results : BFR significantly increased absolute and relative MVIC (P < 0.001, P = 0.001), MBP (P = 0.011, P = 0.008), and TW (P = 0.006, P = 0.007) from pretraining values, whereas only absolute MVIC increased without BFR (P = 0.047). However, the MVIC increase with BFR exercise (35.88 +/- 14.83 N[middle dot]m) was significantly greater (P = 0.040) than without BFR exercise (16.71 +/- 17.79 N[middle dot]m). Conclusions : Short-term BFR exercise significantly increased strength endurance, muscle strength, and MBP in national-level para-alpine standing skiers. Our study provides new evidence that BFR exercise can improve local muscle blood perfusion during high-intensity exercise and informs BFR exercise strategies for athletes with disabilities. [ABSTRACT FROM AUTHOR]

Aims: The evidence for joint and independent associations of low muscle mass and low muscle strength with diabetes is limited and mixed. The study aimed to determine the associations of muscle parameters (muscle mass, strength, quality, and sarcopenia) and sarcopenia obesity with diabetes, and the previously unstudied mediating effect of inflammation., Materials and Methods: A total of 13,420 adults from the 2023 China National Health Survey (CNHS) and 5,380 adults from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) were included in this study. Muscle mass was determined using bioelectrical impedance analysis (BIA) in the CNHS, and whole-body dual X-ray absorptiometry (DXA) in the NHANES. Muscle strength was assessed using digital hand dynamometer. Multivariate logistic regression models were used to evaluate the associations of muscle parameters and sarcopenia obesity with diabetes. Inflammatory status was assessed using blood cell counts and two systemic inflammation indices (platelet-to-lymphocyte ratio (PLR) and system inflammation response index (SIRI)). Mediation analysis was conducted to examine inflammation's role in these associations., Results: Low muscle mass and strength were independently related to diabetes. Low muscle quality was associated with elevated diabetes risk. Sarcopenia has a stronger association with diabetes compared to low muscle strength alone or mass alone (CNHS, odds ratio (OR) = 1.93, 95 % confidence interval (CI):1.64-2.27; NHANES, OR = 3.80, 95 %CI:2.58-5.58). Participants with sarcopenia obesity exhibit a higher risk of diabetes than those with obesity or sarcopenia alone (CNHS, OR = 2.21, 95 %CI:1.72-2.84; NHANES, OR = 6.06, 95 %CI:3.64-10.08). Associations between muscle parameters and diabetes were partially mediated by inflammation (mediation proportion: 1.99 %-36.64 %, P < 0.05)., Conclusion: Low muscle mass and muscle strength are independently or jointly associated with diabetes, and inflammation might be a potential mechanism underlying this association. Furthermore, the synergistic effects of sarcopenia and obesity could significantly increase diabetes risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The purpose of this study was to establish the one-repetition maximum (1RM) prediction equations of a biceps curl, bench press, and squat from the submaximal skeletal muscle strength of 4–10RM or 11–15RM in older adults. The first group of 109 participants aged 60–75 years was recruited to measure their 1RM, 4–10RM, and 11–15RM of the three exercises. The 1RM prediction equations were developed by multiple regression analyses. A second group of participants with similar physical characteristics to the first group was used to evaluate the equations. The actual measured 1RM of the second group correlated significantly to the predicted 1RM obtained from the equations (r values were from .633–.985), and standard error of estimate ranged from 1.08–5.88. Therefore, the equations can be used to predict 1RM from submaximal skeletal muscle strength accurately for older adults. [ABSTRACT FROM AUTHOR]

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]

Objective To summarize the clinical, muscle pathology and molecular biological features of late-onset glycogen storage disease type II (GSD II). Methods and Results Five patients with late - onset GSD II diagnosed and treated in The Fifth Affiliated Hospital of Zhengzhou University from January 2013 to January 2020 were selected. The main clinical manifestations of 5 patients were weakness of raising the head, weakness of the proximal extremities, decreased muscle tone, fatigue intolerance, and dyspnea. The activity of acid α-glucosidase (GAA) was significantly reduced. HE staining of muscular tissues in 5 patients showed vacuole-like changes of different sizes, different numbers, and irregular shapes in most muscle fibers. Modified Gomori trichrome (MGT) staining showed a large number of blue and purple particles deposited in the vacuole. Periodic acid-Schiff (PAS) staining showed the glycogen content in the vacuoles were increased in 4 cases, and the glycogen content in the vacuoles were lost in one case. GAA gene testing showed that 9 mutations were detected in 5 patients, and 4 cases were compound heterozygous mutations, which were derived from father and mother respectively. The c.1320&lowbar;1322delGAT (p.Met440del) was a deletion mutation, c.2331G > C (p.Thr777Thr) was a synonymous mutation, c.2237G > A (p.Trp746*) was a nonsense mutation, c.877G > A (p.Gly293Arg) was a missense mutation, c.2238G > C (p. Trp746Cys) was a missense mutation, c.784G > A (p.Glu262Lys) was a missense mutation, c.2014C > T (p. Arg672Trp) was a missense mutation, and c. 2332 - 2A > G was a splicing mutation. One case was homozygous mutation of c. 1432G > A (p. Gly478Arg), which originated from the mother. Among them, c. 2331G > C, c. 1432G > A and c. 2332 - 2A > G were reported for the first time at home and abroad. Conclusions The clinical manifestations of late - onset GSD II are weakness of proximal limbs and dyspnea. The activity of GAA in peripheral serum is decreased significantly. Muscle tissue pathology is characteristic. GAA gene mutations are mainly compound heterozygous mutation, c.2331G > C, c.1432G > A and c.2332-2A > G are new mutations, which extended the mutation spectrum of GAA gene. [ABSTRACT FROM AUTHOR]