Muscle Density Research Articles

Myxospore density of Kudoa inornata varies significantly within symmetrical white muscle tissue replicates of its fish host, the spotted seatrout, Cynoscion nebulosus

The spotted seatrout, Cynoscion nebulosus, is a popular game fish in the southeastern USA. It is estimated that nearly 90% of the adult population in South Carolina estuaries are infected in their skeletal muscle by the myxosporean, Kudoa inornata. However, little is known about this parasite’s biology, including the distribution and densities of myxospores within tissues of infected fish, which we expect affect the physiology of their hosts. In order to correlate densities with physiological parameters in future studies, we quantified the myxospores density in muscle and characterized the variation among individual fish. Naïve juvenile seatrout was experimentally infected via presumed K. inornata actinospores exposure to raw seawater. A plug of muscle was extracted from two bilaterally symmetrical regions in the epaxial fillet from fresh and frozen carcasses. Variation in density data was calculated both within and among individuals. Within individuals, density counts were compared between left- and right-side biopsies. There was no significant difference between fresh and frozen plugs, and variation among individuals accounted for the greatest proportion of variation at 68.8%, while variation within individuals was substantial at 25.6%. Simulation and correlation tests confirmed that bilaterally symmetrical replicates varied significantly within individuals. When sampled from areas surrounding the initial biopsies, myxospore density estimates were more similar than between sides. Our findings have important implications for sampling design, particularly for studies investigating physiological parameters at the cellular or molecular level in association with parasite infection.

The predictive value of albumin to alkaline phosphatase ratio for vertebral refractures in postmenopausal women.

To investigate the clinical value of serum albumin to alkaline phosphatase ratio (AAPR) in predicting the risk of osteoporotic vertebral refractures group (OVRFs) after percutaneous vertebral augmentation (PVA) in postmenopausal women. This is a retrospective case-control study including a series of postmenopausal women patients with osteoporotic vertebral fracture (OVF) and underwent PVA. Patients were divided into OVRFs and non-OVRFs. COX model was used to evaluate the correlation between preoperative AAPR and OVRFs after PVA. The receiver operating characteristic (ROC) curve and Kaplan-Meier method were used to analyze the predictive value of AAPR for the incidence of OVRFs. A total of 305 patients were included in the final study, and the incidence of postoperative OVRFs was 28.9%. Multivariate COX analysis showed that advanced age (HRs = 1.062, p = 0.002), low BMI (HRs = 0.923, p = 0.036), low AAPR (HRs = 0.019, p = 0.001), previous fall history (HRs = 3.503, p = 0.001), denosumab treatment (HRs = 0.409, p = 0.007), low L3 BMD (HRs = 0.977, p = 0.001) and low L3 paravertebral muscle density (PMD)value (HRs = 0.929, p = 0.001)) were closely related to the incidence of OVRFs. The area under the curve (AUC) of AAPR for predicting OVRFs was 0.740 (p < 0.001), and the optimal diagnostic cut-off value was 0.49. Kaplan-Meier curve analysis showed that low AAPR group (< 0.49) was significantly associated with lower OVRFs-free survival (p = 0.001; log-rank test). AAPR is an independent risk factor for OVRFs after PVA in postmenopausal women, and it can be used as an effective index to predict OVRFs.

Body composition in recurrent prostate cancer and the role of steroidogenic genotype.

Hormone therapy (HT) to treat prostate cancer is reported to cause adverse changes in body composition. Clinically, interpatient body composition changes are heterogeneous, but the biologic and clinical determinants of body composition toxicity are unknown. Herein, we test the hypothesis that inherited polymorphisms in steroidogenic genes are associated with differential change in body composition after HT. Men with biochemically recurrent prostate cancer (BCR) who received 8 months of LHRH analog (LHRHa) +/- abiraterone acetate (AAP) were eligible if they had: 1) CT imaging of L3 prior to and after treatment, and 2) nucleated cells collected. Cardiometabolic co-morbidities were retrospectively extracted. Body composition was measured using an AI-based segmentation tool. Germline DNA whole exome or genome sequencing was performed. In 162 men treated with 8 months of HT, median skeletal muscle mass (SMMi) loss was 6.6% and subcutaneous adipose gain was 12.3%. Men with type 2 diabetes had higher loss of SMMi after treatment (-11.1% vs. -6.3%, p = 0.003). For the 150 men with germline NGS, SRD5A2 rs523349 genotype was associated with differential loss in skeletal muscle density after HT, (-1.3% vs. -7.1%, p=0.04). In addition, HSD3B1 rs104703 genotype was associated with decreased baseline visceral adipose tissue (63.0 cm2/m2 vs. 77.9, p=0.05). In men with BCR, HT induced notable loss of skeletal muscle and increased subcutaneous adipose tissue. An inherited polymorphism in SRD5A2 and T2DM were associated with differential skeletal muscle toxicity. These findings suggest that inherited polymorphisms may contribute to the body composition toxicity observed with HT.

Association between trochanteric fractures and gluteal muscle size, density in older women: a cross-sectional study at a university hospital

PurposeThis study aimed to investigate differences in hip muscle area and density between older women with femoral neck fractures (FNF) and trochanteric fractures (TRF).DesignCross-sectional study.Setting and participantsThe study was conducted...

Association of computed tomography-derived pectoralis muscle area and density with disease severity and respiratory symptoms in patients with chronic obstructive pulmonary disease: A case-control study

Rationale and objectivesComputed tomography (CT) is commonly used and offers an additional viewpoint for evaluating extrapulmonary symptoms, disease severity, and muscle atrophy. This study assessed whether the pectoralis muscle area (PMA) and pectoralis muscle density (PMD) are lower in patients with chronic obstructive pulmonary disease (COPD) than in healthy controls and elucidated their relationships with these variables. Materials and methodsThe participants were enrolled in the hospital outpatient clinic between October 2023 and May 2024. Information was obtained from questionnaires, lung function, and CT imaging findings. On full-inspiratory CT, the PMA and PMD were measured at the aortic arch level using predetermined attenuation ranges of −29 and 150 Hounsfield units. We observed lower PMA and PMD and evaluated their associations with lung function, respiratory symptoms, and CT imaging findings in patients with COPD. ResultsOverall, 120 participants were enrolled at baseline (60 healthy controls and 60 patients with COPD). PMA and PMD were lower with progressive airflow limitation severity in those with COPD. The degree of emphysema and air trapping, as well as lung function, were correlated with PMA and PMD (P < 0.05), although not with the COPD Assessment Test or modified Medical Research Council scores (P > 0.05). ConclusionParticipants with COPD had smaller PMA and PMD. These measurements were correlated with the severity of airflow limitation, lung function, emphysema, and air trapping, suggesting that these features of the pectoralis muscle obtained from CT are helpful in assessments of patients with COPD.

Technical and biological reliability of pQCT measured bone and muscle tissue quality across the age-span

Introduction: Reliable peripheral quantitative computed tomography (pQCT) assessment is essential to the accurate longitudinal reporting of bone and muscle quality. However, the between-day reliability of pQCT and the influence of age on outcome reliability is currently unknown.Objective: To quantify the same- and between-day reliability of morphological pQCT at proximal and distal segments of the forearm, shank, and thigh, and explore the influence of participant body size, age, and sex on outcome reliability.Methods: Men and women (49 % female, 18-85 years, n=72-86) completed two consecutive-day pQCT testing sessions, where repeat measurements were conducted on day-one for technical error, and between-day for biological error quantification. Testing was undertaken following best practice body composition testing guidance, including standardized presentation and consistent time-of-day.Results: All measurements of bone were classified as having ‘good’ to ‘excellent’ reliability [intraclass correlation coefficient (r=0.786- 0.999], as were measurements of muscle area (ICC r=0.991-0.999) and total fat (r=0.996-0.999). However, between- and same-day muscle density measurements at the thigh and forearm were classified as ‘poor’ (r=0.476) and ‘moderate’ (r=0.622), respectively. Likewise, intramuscular fat area at the thigh was classified as ‘moderate’ (r=0.737) for between-day measurement. Biological error was inflated compared to technical error by an average of 0.4 % for most measurements. Error values tended to increase proportionally with the amount of tissue quantified and males had significantly greater biological error for measurement of distal tibial bone (p<0.002) and trabecular area (p<0.002). Biological error was inflated among older adults for measurement of forearm muscle density (p<0.002).Conclusions: Most pQCT outcomes can be implemented with confidence, especially outcomes that assess bone area and density at any of the radial, tibial, and femoral sites investigated herein. However, it is important to account for the influence of biological measurement error in further studies, especially for muscle and intramuscular fat outcomes derived by pQCT.

Transcriptome sequencing reveals the potential mechanisms of dietary lutein regulation on chicken leg muscle development

Lutein is an antioxidant that can indicate the oxidative status of organisms through its coloration and may be involved in the development process of chicken skeletal muscle. In this study, after feeding Nanhai Yellow Chickens with lutein-containing feed for 21 d, the lutein group significantly increased the muscle fiber diameter and decreased the fiber density in the chicken's leg muscles compared to the control group. To elucidate the potential regulatory mechanisms by which lutein is involved in muscle development, RNA-seq was used to detect changes in gene expression in chicken leg muscle tissue. After data analysis, a total of 249 significantly differentially expressed genes (DEG) were identified, including TGF-β superfamily (MSTN and TGFB1) and nonreceptor tyrosine kinase c-Src (SRC). Results from GO and KEGG analysis showed that the DEGs were enriched in GO terms such as positive regulation of the ERK1/ERK2 cascade and negative regulation of myoblast differentiation, as well as signaling pathways including the Toll-like receptor signaling pathway and the MAPK signaling pathway. These significantly enriched GO terms and pathways are closely related to muscle development, suggesting that lutein may play an important role in the process of chicken muscle development. This study provides insights into the regulatory mechanisms of dietary lutein on chicken muscle development.

The correlation of CT-derived muscle density, skeletal muscle index, and visceral adipose tissue with nutritional status in severely injured patients.

This study explored if computerized tomography-derived body composition parameters (CT-BCPs) are related to malnutrition in severely injured patients admitted to the Intensive Care Unit (ICU). This prospective cohort study included severely injured (Injury Severity Score ≥ 16) patients, admitted to the ICU of three level-1 trauma centers between 2018 and 2022. Abdominal CT scans were retrospectively analyzed to assess the CT-BCPs: muscle density (MD), skeletal muscle index (SMI), and visceral adipose tissue (VAT). The Subjective Global Assessment was used to diagnose malnutrition at ICU admission and on day 5 of admission, and the modified Nutrition Risk in Critically ill at admission was used to assess the nutritional risk. Seven (11%) of the 65 analyzed patients had malnutrition at ICU admission, increasing to 23 patients (35%) on day 5. Thirteen (20%) patients had high nutritional risk. CT-BCPs were not related to malnutrition at ICU admission and on day 5. Patients with high nutritional risk at admission had lower MD (median (IQR) 32.1 HU (25.8-43.3) vs. 46.9 HU (37.7-53.3); p < 0.01) and higher VAT (median 166.5 cm2 (80.6-342.6) vs. 92.0 cm2 (40.6-148.2); p = 0.01) than patients with low nutritional risk. CT-BCPs do not seem related to malnutrition, but low MD and high VAT may be associated with high nutritional risk. These findings may prove beneficial for clinical practice, as they suggest that CT-derived parameters may provide valuable information on nutritional risk in severely injured patients, in addition to conventional nutritional assessment and screening tools. Level III, Prognostic/Epidemiological.

Dldhcri3 zebrafish exhibit altered mitochondrial ultrastructure, morphology, and dysfunction partially rescued by probucol or thiamine.

Dihydrolipoamide dehydrogenase (DLD) deficiency is a recessive mitochondrial disease caused by variants in DLD, the E3 subunit of mitochondrial α-keto (or 2-oxo) acid dehydrogenase complexes. DLD disease symptoms are multisystemic, variably manifesting as Leigh syndrome, neurodevelopmental disability, seizures, cardiomyopathy, liver disease, fatigue, and lactic acidemia. While most DLD disease symptoms are attributed to dysfunction of the pyruvate dehydrogenase complex, the effects of other α-keto acid dehydrogenase deficiencies remain unclear. Current therapies for DLD deficiency are ineffective, with no vertebrate animal model available for preclinical study. We created a viable Danio rerio (zebrafish) KO model of DLD deficiency, dldhcri3. Detailed phenotypic characterization revealed shortened larval survival, uninflated swim bladder, hepatomegaly and fatty liver, and reduced swim activity. These animals displayed increased pyruvate and lactate levels, with severe disruption of branched-chain amino acid catabolism manifest as increased valine, leucine, isoleucine, α-ketoisovalerate, and α-ketoglutarate levels. Evaluation of mitochondrial ultrastructure revealed gross enlargement, severe cristae disruption, and reduction in matrix electron density in liver, intestines, and muscle. Therapeutic modeling of candidate therapies demonstrated that probucol or thiamine improved larval swim activity. Overall, this vertebrate model demonstrated characteristic phenotypic and metabolic alterations of DLD disease, offering a robust platform to screen and characterize candidate therapies.

Myosteatosis predicts bariatric surgery response: A longitudinal study in patients with morbid obesity.

Data on the preoperative factors for bariatric surgery response in patients with morbid obesity are limited, and there are no studies on the relationship between myosteatosis and surgery response. We investigated the preoperative factors determining bariatric surgery response and the impact of preoperative muscle fat infiltration on bariatric surgery response. This retrospective longitudinal cohort study included 125 individuals (37 men, 88 women) with morbid obesity who underwent bariatric surgery. Muscle fat infiltration (skeletal muscle fat index [SMFI]) was evaluated using computed tomography-based psoas muscle mass and density at the 4th lumbar level. A bariatric surgery response was defined as ≥50% excessive weight loss at one year postoperatively. Before bariatric surgery, the patient mean body weight and body mass index (BMI) were 107.0 kg and 39.0 kg/m2, respectively. After one year, the mean body weight was 79.6 kg. The mean excessive weight loss at one year was 75.6% and 102 (81.6%) patients were categorized as responders. There were no statistically significant differences in initial BMI, age, sex, or proportion of diabetes between responders and non-responders. Responders were more likely to have lower SMFI and triglyceride and glycated hemoglobin A1c levels than non-responders at baseline (P<0.05). Multiple logistic regression analysis showed that a lower baseline SMFI was associated with bariatric surgery response (odds ratio=0.31, 95% confidence interval=0.14-0.69, P=0.004). Preoperative myosteatosis may determine the response to bariatric surgery.

CT Derived Measurement of Body Composition: Observations from a Comparative Analysis of Patients with Colorectal and Lung Cancer

Background CT-derived measures of body composition have been shown to have prognostic value in patients with cancer. However, few studies have compared these observations across tumor types and stages of disease. The aim of the present study was to compare body composition measures between two types of cancers, i.e. colorectal cancer (CRC), which is less inflammatory and patients maintain body composition over a longitudinal study period, whereas lung cancer (LC) is proinflammatory and patients lose more fat and muscle mass using a standard methodology. Methods Clinicopathological characteristics, including those pertaining to nutritional risk/status and systemic inflammation in patients with colorectal cancer (CRC, n = 1047) and lung cancer (LC, n = 662), were compared. The CT image at L3 was used to assess body composition. Comparison of these cohorts was carried out using the chi-square test. Binary logistic regression analysis was performed to assess the impact of clinico-pathological variables on body composition, and scatter plots were used to examine the relationship between body mass index (BMI) and CT-derived measures of body composition. Results According to CT-derived body composition, high subcutaneous (SFI) and visceral fat index (VFI) were common (>70%) in both CRC and LC. Also, low skeletal muscle index (SMI) and density (SMD) were approximately 40–50% and 60–70% in both CRC and LC. Compared with CRC, patients with LC had a higher American Society of Anaesthesia (ASA) (P < 0.001), Malnutrition Universal Screening Tool (MUST) (P < 0.001), modified frailty index (mFI) (P < 0.001), modified Glasgow Prognostic Score (mGPS) (P < 0.001), and neutrophil lymphocyte ratio (NLR) (P < 0.001) scores. On binary logistic regression analysis, MUST, mFI, and NLR were predictors of subcutaneous adiposity (P < 0.05); type of cancer, MUST, and mFI were predictors of visceral obesity (P < 0.001); age, type of cancer, MUST, and mGPS were predictors of low SMI (P < 0.001); and age, type of cancer, mFI, and mGPS were predictors of low SMD (P < 0.05). There was a similar relationship between BMI and other measures of CT-derived body composition across two types of cancers. Conclusion Obesity and low skeletal muscle mass were common in both CRC and LC cohorts despite large differences in comorbidity, nutritional risk, systemic inflammation, and survival, even when normalized for TNM stage. These observations would support the hypothesis that, although prognostic, CT derived body composition analysis primarily reflects patient constitution rather than the effect of tumor stage in patients with cancer. The systemic inflammatory response, as evidenced by mGPS, can be considered as an important therapeutic target and loss of muscle mass in patients with advanced cancer is related to the systemic inflammatory response.

The chest CT perspective on sarcopenia: Exploring reference values for muscle mass quantity/quality and its application in old adults

ObjectiveTo determine reference values for diagnosing sarcopenia through chest CT scans and evaluate their suitability for use among the Chinese old population. MethodsChest CT scans were obtained from 500 healthy individuals aged 19–39. Skeletal muscle mass was assessed on chest CT at the level of T4 by the skeletal muscle area (T4SMA), skeletal muscle index (T4SMI), T12 erector spinae muscle area (T12ESMA), and T12 skeletal muscle index (T12SMI), as well as skeletal muscle density (SMD) at T4 and T12 levels. The diagnostic threshold for sarcopenia was defined as a gender-specific value below 2 SD of the mean value in the young group. These cutoff values were then applied to a group of older adults aged 65 and over. ResultsDiagnostic thresholds for low skeletal muscle in men were 110.05 cm², 36.01 cm²/m², 29.56 cm², and 9.65 cm²/m² for T4SMA, T4SMI, T12ESMA, and T12SMI, respectively. For women, the thresholds were: 69.93 cm², 26.51 cm²/m², 17.84 cm²/m², and 6.87 cm²/m², respectively. Diagnostic thresholds for low SMD were 38.63HU in men, 34.74 HU for women at T4 level. At T12 level, the cutoff values were 40.94 HU for men and 36.63 HU for women. Sarcopenia prevalence in men, defined by T4SMA, T4SMI, T12ESMA, and T12SMI cutoffs, was 35.6%, 18.9%, 36.7%, and 23.7%, respectively. In women, sarcopenia prevalence was 5.1%, 3.2%, 3.2%, and 1.9%, respectively. ConclusionThis study established reference values for sarcopenia diagnosis through chest CT scans among the Chinese population, highlighting the importance of utilizing chest CT scans for sarcopenia detection and muscle health monitoring in older adults.

Thoracic sarcopenia measured by Hounsfield unit average calculation predicts morbidity and mortality in coronary artery bypass grafting.

The aim of the study was to investigate the potential prognostic role of preoperative measurement of erector spinae myosteatosis with Hounsfield unit average calculation as a marker for sarcopenia and frailty in patients undergoing coronary bypass surgery. Preoperative computer tomography-derived measurements of 479 consecutive patients undergoing coronary bypass surgery between January 2017 and December 2019 were retrospectively performed. The erector spinae muscle at the level of the 12th vertebra was manually outlined bilaterally on the axial computer tomography slices and Hounsfield unit average calculation was performed. The lower quartile of muscle density values was defined as myosteatotic and thus sarcopenic. Sarcopenic (n = 121) versus non-sarcopenic patients (n = 358) were compared regarding postoperative morbidity and short- and long-term mortality. Results were adjusted for age, body mass index, atrial fibrillation and hypertension using inverse probability weighting. Sarcopenia was associated with higher 30-day mortality (4.1% vs 0.8%; P = 0.012), mid-term mortality after 1 year (9.3% vs 3.1%; P = 0.047) and 2 years (10.8% vs 4.2%; P = 0.047). Long-term mortality (5 years) was 20.8% for sarcopenic and 13.0% for non-sarcopenic patients but was not found to be significantly different (P = 0.089). Sarcopenia was associated with higher rates of reintubation (7.5% vs 1.1%; P < 0.001), sternal wound infections (7.5% vs 2.8%; P = 0.039) and acute kidney injury requiring haemodialysis (2.5% vs 0.4%; P = 0.021). In patients undergoing coronary bypass surgery, sarcopenia was associated with increased short-term mortality, mid-term mortality and morbidity. The measurement of erector spinae myosteatosis could be an easy and useful parameter in preoperative risk assessment.

53 Associations between body composition, ClearCode34, and clinical outcomes in localized clear cell renal cell carcinoma

Abstract Background Emerging evidence suggests that pre-surgical body composition is a prognostic factor for cancer outcomes. Lower skeletal muscle quantity and radiodensity have been associated with renal cell carcinoma (RCC) outcomes in other studies, while reports of the relationship between visceral adipose tissue and RCC outcomes have been inconsistent. Mechanisms underlying these associations are unclear but may relate to tumor biology. We leveraged a large molecular epidemiology study of localized clear cell renal cell carcinoma (ccRCC) patients to examine how pre-surgical body composition features were associated with survival post-nephrectomy as well as ClearCode34 status, a previously validated prognostic gene expression signature. Methods The RESOLVE study at Memorial Sloan Kettering Cancer Center is a retrospective study of 1,239 patients with stage I-III ccRCC undergoing nephrectomy without systemic therapy. Pre-surgical CT scans at the third lumbar vertebrae were segmented for the cross-sectional areas and radiodensities of skeletal muscle, subcutaneous adipose and visceral adipose tissues using Automatica software. Formalin-fixed, paraffin-embedded tumor tissue samples were available for 929 patients, which were sent to the University of North Carolina at Chapel Hill and assayed for gene expression. RNA was extracted from these samples and analyzed using the Nanostring nCounter system on a custom panel of 356 genes, including the 34 genes used in the ClearCode34 assay. Of the 929 patients with tumor tissue available, gene expression data from 837 patients (90.1%) passed RNA extraction and data QC. Samples were classified into either ccA or ccB ClearCode34 classes using a reference data set and PAM (prediction analysis of microarrays) centroid-based classification. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for disease-free survival (DFS) within five years of diagnosis using Cox proportional hazards models for both body composition variables and ClearCode34 subtype. We also estimated odds ratios (ORs) and 95% CIs for associations between ClearCode34 subtype and body composition with logistic regression. All multivariable models were adjusted for age, sex, and all body composition variables. Results Of the 837 patients in our analytic sample, 219 (26%) had ccB tumors. Men, patients with high stage or grade tumors, and patients with chronic kidney disease prior to nephrectomy were more likely to present with ccB tumors. Lower skeletal muscle density (SMD) was significantly associated with lower five-year DFS [HR (95% CI) per 10 HU decrease in SMD: 1.7 (1.2, 2.3)]. While no other body composition features were significantly associated, we also observed non-significantly increased HRs for VATI and VATD [HR (95% CIs): 1.3 (0.8, 2.0) and 1.5 (0.9, 2.7), respectively]. ClearCode34 subtype was significantly associated with five-year DFS, where patients with ccB tumors had poorer DFS [HR (95% CI): 1.7 (1.1, 2.5)] compared to patients with ccA tumors. Notably, we observed no significant associations between any body composition feature and ClearCode34 in univariable analyses. However, in multivariable models that accounted for all body composition variables simultaneously as well as age and sex, lower SMD emerged as significantly associated with ccB subtype [OR (95% CI) per 10 HU decrease in SMD: 1.3 (1.0, 1.7)]. Conclusions Our findings suggest that the associations observed between body composition features and clinical outcomes in ccRCC may be related to tumor biology. Lower pre-surgical SMD, which may represent myosteatosis and metabolic dysregulation in ccRCC patients, was associated with both decreased five-year DFS and an increased likelihood of presenting with a more aggressive ccB tumor. Future studies should investigate body composition features related to ccRCC prognosis and additional markers of tumor biology, such as immune-related gene expression patterns, to extend these findings.

Both rapid hyperplasia and hypertrophy promoted skeletal muscle growth in mandarin fish Siniperca chuatsi, compared to big-eye mandarin fish Siniperca kneri

As important cultured fishes in China, mandarin fish, Siniperca chuatsi and big-eye mandarin fish, Siniperca kneri share similar external morphology and genomes, but have significant differences in growth rates. In this study, we used 6 mph (month post hatching) mandarin fish and big-eye mandarin fish to compare differences in skeletal muscle growth over a one-month period, and use transcriptomes to explore the reasons for the growth differences. The results showed that the different value in number of muscle fibers (2.72 times), density (2.56 times), area (1.95 times) and diameter (2.73 times) of mandarin fish are significantly higher than that of big-eye mandarin fish (P<0.05). Hypertrophy (Contribution rate: 97.9%) is the dominant factor in big-eye mandarin fish, and both hypertrophy and hyperplasia (Contribution rate: 2.1%) were significantly different from mandarin fish (P<0.05). Transcriptome results showed that differential genes were enriched in proliferation of satellite cells, protein synthesis and degradation. Further analysis of the transcriptome results showed that the number of Pax7-positive cells per unit area of mandarin fish was 2.3 fold higher that of big-eye mandarin fish (P<0.05). Myod, pax3, pax7, and myf5 mRNA expression of mandarin fish were significantly higher than those of big-eye mandarin fish(P<0.05). In muscle fiber fusion, mef2, myog, and myomaker mRNA expression of mandarin fish were significantly higher than that of big-eye mandarin fish (P < 0.05). In protein deposits, the results showed that the muscle fiber area of mandarin fish was 2.85 times larger than that of big-eye mandarin fish by comparing the muscle fiber area with the same number of nuclei. Polr2a, mtorc1, 4e-bp1, s6, e1, murf, foxo3, atg5, beclin, and atg14 mRNA expression of mandarin fish were significantly higher than that of big-eye mandarin fish (P < 0.05), while eef2, eif2α, gcn2, eif2b, capn and cast of mandarin fish was significantly lower than that of big-eye mandarin fish (P < 0.05). This work verified that the skeletal muscle growth rate of mandarin fish is faster than that of big-eye mandarin fish. The greater number and higher activity of satellite cells of mandarin fish increased hyperplasia efficiency, and the faster fusion rate and protein precipitation rate increased hypertrophy efficiency. Both hyperplasia and hypertrophy contribute to faster skeletal muscle growth of mandarin fish than that of big-eye mandarin fish.

Sarcopenia is associated with short- and long-term mortality in patients with acute-on-chronic liver failure.

While sarcopenia is recognized as a predictor of mortality in cirrhosis, its influence on acute-on-chronic liver failure (ACLF) remains uncertain. Despite multiple studies examining the impact of sarcopenia on short-term mortality in patients with ACLF, the sample size of these studies was limited, and their outcomes were inconsistent. Therefore, this study aimed to explore the impact of sarcopenia on both short- and long-term mortality in patients with ACLF. This retrospective cohort study included 414 patients with ACLF that were treated between January 2016 and September 2022. Sarcopenia was diagnosed based on the measurement of the skeletal muscle index at the third lumbar vertebra (L3-SMI). Subsequently, the patients were divided into sarcopenia and non-sarcopenia groups. We analysed the basic clinical data of the two groups. Multivariate Cox proportional analysis was used to analyse short-term (28days) and long-term (1year and overall) mortality rates. A total of 414 patients were included, with a mean age of 52.88±13.41years. Among them, 318 (76.8%) were male, and 239 (57.7%) had sarcopenia. A total of 280 (67.6%) patients died during the study period. Among them, 153 patients died within 28days (37%) and 209 patients died within 1year (50.5%). We found that the 28-day, 1-year and overall mortality rates in the sarcopenia group were significantly higher than those in the non-sarcopenia group (37% vs. 22.3%, P<0.01; 50.5% vs. 34.9%, P<0.01; and 67.6% vs. 53.1%, P<0.01, respectively). Multivariate Cox regression analysis revealed that sarcopenia was significantly associated with increased mortality. The hazard ratios for sarcopenia were 2.05 (95% confidence interval [CI] 1.41-3.00, P<0.01) for 28-day mortality, 1.81 (95% CI 1.29-2.54, P<0.01) for 1-year mortality and 1.82 (95% CI 1.30-2.55, P<0.01) for overall mortality. In addition, muscle density and international normalized ratio were associated with short- and long-term mortality. Sarcopenia is associated with both short- and long-term mortality in patients with ACLF. Therefore, regular monitoring for sarcopenia is important for these patients.

Lower skeletal muscle density and airway structure on computed tomography in asthma

BackgroundLower skeletal muscle density may reflect muscle adiposity and metabolic dysregulation that potentially impair disease control and lung function independent of high body mass index (BMI) in patients with asthma. ObjectiveTo investigate whether the lower density of pectoralis muscles (PMs) and erector spinae muscles (ESMs) on chest computed tomography was associated with airway structural changes in patients with asthma. MethodsConsecutive patients with asthma and healthy controls undergoing chest computed tomography were retrospectively analyzed. The ESM and PM density, areas of subcutaneous adipose tissue near the PM and epicardial adipose tissue, wall area percent of the airways, and airway fractal dimension (AFD) were quantified on computed tomography. ResultsThe study included 179 patients with asthma (52% women) and 88 controls (47% women). All the controls were 60 years old or younger. The PM and ESM density in female patients with asthma who were 60 years old or younger were significantly lower than those in controls after adjustment for BMI. In female patients with asthma at all ages, lower PM and ESM density (but not subcutaneous or epicardial adipose tissue area) was associated with greater wall area percent of the airways and lower AFD after adjusting for age, height, BMI, smoking status, blood eosinophil count, and oral corticosteroid use. The only association between ESM density and AFD was found in male patients with asthma. ConclusionLower skeletal muscle density may be associated with airway wall thickening and less complexity of the airway luminal tree in female patients with asthma.

Thigh muscle by CT images as a predictor of mortality in patients with newly diagnosed colorectal cancer

This study aimed to evaluate the prognostic value of thigh muscle assessed by CT images to predict overall mortality in patients with colorectal cancer (CRC). This was a multicenter cohort study including adults (≥ 18 years old) newly diagnosed with CRC, who performed a diagnostic computed tomography (CT) exam including thigh regions. CT images were analyzed to evaluate skeletal muscle (SM in cm2), skeletal muscle index (SMI in cm2/m2), and skeletal muscle density (SMD in HU). Muscle abnormalities (low SM, SMI, and SMD) were defined as the values below the median by sex. Kaplan–Meyer curves and hazard ratios (HRs) for low SM, SMI and SMD were evaluated for overall mortality, stratified by sex. A total of 257 patients were included in the final analysis. Patients’ mean age was 62.6 ± 12.1 years, and 50.2% (n = 129) were females. In males, low thigh SMI was associated with shorter survival (log-rank P = .02). Furthermore, this low thigh SMI (cm2/m2) was independently associated with higher mortality rates (HR adjusted 2.08, 95% CI 1.03–4.18). Our additional findings demonstrated that low SMD was independently associated with overall mortality among early-stage patients (I–III) (HR adjusted 2.78, 95% CI 1.26–6.15).

Body fat percentage and Body Mass Index in association with menstrual irregularities in young adults: A cross-sectional study

HIGHLIGHTS 1. Body fat percentage and BMI were found to be associated with menstrual cycle and menstrual bleeding period.2. The odds of having a prolonged menstrual cycle were increased by a factor of 1.109 with an increase of one unit of body fat percentage, while the odds of having a prolonged menstrual bleeding period was decreased by a factor 0.887 with an increase of one unit of body fat percentage. ABSTRACT Objectives: Body fat percentage measures overall amount of fat as a proportion of total body weight. Basal metabolic index (BMI) is an unreliable predictor of body fat percentage as excess fat, lean, muscle, or bone density are indifferentiable. However, the relation between body fat percentage and BMI on menstrual characteristics are still unclear. The aim was to compare the correlations between body fat percentage and BMI towards menstrual characteristics.Materials and Methods: A cross-sectional sample of 211 young adults was taken by means of cluster random sampling. Cross tabulations were performed between variables and Pearson's chi square value were observed. Multiple logistic regressions were performed to observe the odds ratio and 95% confidence interval.Results: Body fat percentage was found to be associated with menstrual cycle (p=0.000) and menstrual bleeding period (p=0.000) but not daily pads usage, intermenstrual bleeding, and menstrual pains. Age was found not to correlate with any of the collected menstrual characteristic data. BMI was also found to be associated with menstrual cycle (p=0.008) and menstrual bleeding period (p=0.003). Further analysis showed that a one unit increase of body fat percentage was linearly correlated with increased of menstrual cycle by a factor of 1.109 days (p&lt;0.01) and a decreased of menstrual bleeding period by a factor of 0.887 days (p&lt;0.01).Conclusion: Although both body fat percentage and BMI showed associations with menstrual cycle and menstrual bleeding period, only body fat percentage was linearly correlated with menstrual cycle and menstrual bleeding period.

Does computed tomography-derived volumometry and densitometry of psoas muscle really correlate with complications in rectal cancer patients after elective surgery?

Although sarcopenia is recognized as one of the risk factors for increased morbidity after resection for colorectal cancer, the question of the most appropriate way to identify and quantify it is still unresolved. This is a retrospective unicentric study following patients undergoing elective resection of the rectum for carcinoma with available staging computed tomography (CT) of the trunk. Psoas muscle density (PMD) and its area relative to patient height psoas muscle index (PMI) at the level of inferior vertebral end plate of third lumbar vertebra (L3) were assessed using an initial staging CT scan of the trunk. Post-operative complications, evaluated according to the Clavien-Dindo classification, and blood samples on post-operative days (POD) 3 and 5 were also recorded in the study population. Patients were divided into groups with complicated and uncomplicated post-operative course, and observed parameters were then statistically compared. The correlation of PMI values with the development of post-operative complications was not confirmed in a data set of 206 patients. PMD values were found to be borderline statistically significant in patients with complicated post-operative course, while in the group of patients with severe complications (Clavien-Dindo III-IV), there was no statistically significant difference in PMI or PMD values. The same results were obtained when comparing patients with anastomotic leak (AL). It was confirmed that operations on the lower rectum are riskier for the development of post-operative complications. The secondary objective of our study regarding serum C-reactive protein (CRP) levels of 3rd and 5th POD gave us the answer in the form of cutoff values of 115.7 mg/L (3rd POD) and 76 mg/L (5th POD). PMD appears to be a promising tool for predicting post-operative morbidity in patients after rectal resection, but a clear consensus on the method of measurement, interpretation of results and cutoff values is needed. Lower rectal resections are burdened with a higher risk of post-operative complications, especially AL. Monitoring of CRP levels remains an important marker in the prediction of AL due to its negative predictive value.