A guide for using NIH Image J for single slice cross-sectional area and composition analysis of the thigh from computed tomography

Impact of CFTR modulator therapy on body composition as assessed by thoracic computed tomography: A follow-up study

OBJECTIVE

Treatment with cystic fibrosis transmembrane conductance regulator (CFTR) modulators in individuals with cystic fibrosis (CF) has brought a significant change in forced expiratory volume in 1 second (FEV1) and clinical parameters. However, it also results in weight gain. The aim of our study is to evaluate the effect of CFTR modulator treatment on body composition, measured by computed tomography (CT).

METHODS

Adult subjects with CF under follow-up at La Princesa University Hospital were recruited. All of them were on elexacaftor-tezacaftor-ivacaftor (ELX/TEZ/IVA) treatment. Body composition analysis was conducted using CT scans and an open-source software. The results were then compared with bioimpedance estimations, as well as other clinical and spirometry data.

RESULTS

Our sample consisted of 26 adult subjects. The fat mass compartments on CT scans correlated with similar compartments on bioimpedance, and normal-density muscle mass exhibited a strong correlation with phase angle. Higher levels of very low-density muscle prior to treatment were associated with lower final FEV1 and less improvement in FEV1 after therapy. We observed an increase in total body area (P < 0.001), driven by increases in total fat mass (P < 0.001), subcutaneous fat (P < 0.001), visceral fat (P = 0.002), and intermuscular fat (P = 0.022). The only muscle compartment that showed an increase after treatment was very low-density muscle (P = 0.032).

CONCLUSIONS

CT scans represent an opportunity to assess body composition on CF. Combination treatment with CFTR modulators, leads to an improvement in FEV1 and to an increase in body mass in all compartments primarily at the expense of fat mass.

Application of a Diabetic Foot Smart APP in the measurement of diabetic foot ulcers

AIMS

In the early stage, we developed an intelligent measurement APP for diabetic foot ulcers, named Diabetic Foot Smart APP. This study aimed to validate the APP in the measurement of ulcer area for diabetic foot ulcer (DFU).

METHODS

We selected 150 DFU images to measure the ulcer areas using three assessment tools: the Smart APP software package, the ruler method, and the gold standard Image J software, and compared the measurement results and measurement time of the three tools. The intra-rater and inter-rater reliability were described by Pearson correlation coefficient, intra-group correlation coefficient, and coefficient of variation.

RESULTS

The Image J software showed a median ulcer area of 4.02 cm2, with a mean measurement time of 66.37 ± 7.95 s. The ruler method showed a median ulcer area of 5.14 cm2, with a mean measurement time of 171.47 ± 46.43 s. The APP software showed a median ulcer area of 3.70 cm2, with a mean measurement time of 38.25 ± 6.81 s. There were significant differences between the ruler method and the golden standard Image J software (Z = -4.123, p < 0.05), but no significant difference between the APP software and the Image J software (Z = 1.103, p > 0.05). The APP software also showed good inter-rater reliability and intra-rater reliability, with both reaching 0.99.

CONCLUSION

The Diabetic Foot Smart APP is a fast and reliable measurement tool with high measurement accuracy that can be easily used in clinical practice for the measurement of ulcer areas of DFU.

TRIAL REGISTRATION

Chinese clinical trial registration number: ChiCTR2100047210.

One-leg standing time is a simple measure for loss of skeletal muscle mass and fat deposition in muscle: the J-SHIPP study

BACKGROUNDS

One-leg standing time (OLST) has been frequently used physical performance measure; however, what muscular characteristics OLST represents remains uncertain.

AIM

This cross-sectional study aimed to investigate the association between OLST and muscle characteristics to clarify the possibility of using OLST as a physical performance measure.

METHODS

Study participants comprised 1144 older adults aged 65 years or older. Computed tomography images provided mid-thigh skeletal muscle cross-sectional area and mean attenuation value. OLST was measured for a maximum of 60 s. Static postural instability was assessed using a posturography.

RESULTS

A frequency of OLST < 20 s was increased by quartiles of muscle cross-sectional area (Q1: 33.6, Q2: 12.8, Q3: 13.6, Q4: 11.9%, P < 0.001) and mean attenuation value (Q1: 32.3, Q2: 21.7, Q3: 14.3, Q4: 7.7%, P < 0.001). Results of the multinomial regression analysis indicated that muscle cross-sectional area and mean attenuation value were independently associated with an OLST of less than 20 s. The crude odds ratio of OLST less than 20 s for the lowest quartiles of both cross-sectional area and mean attenuation value was 4.19 (95% CI: 3.01 - 5.84). The cross-sectional area of muscles with greater fat deposition was inversely associated with OLST, while that with smaller fat deposition showed a positive association with OLST, indicating why mean attenuation value and cross-sectional area were independently associated with OLST. No clear relationship was observed with static postural instability.

CONCLUSION

OLST was a simply measurable quantifiable physical measure representing the loss of muscle mass and quality in older adults.

Klotho Null Mutation Involvement in Adenosine A2B Receptor-Related Skeletal Muscle Degeneration

Klotho is known for its age-suppressing function and has been implicated in sarcopenia pathology. It has recently been proposed that the adenosine A2B receptor plays a crucial role in skeletal muscle energy expenditure. However, the association between Klotho and A2B remains elusive. In this study, Klotho knockout mice, aged 10 weeks, and wild-type mice, aged 10 and 64 weeks, were used for comparison in indicators of sarcopenia (n = 6 for each group). PCR was performed to confirm the mice genotypes. Skeletal muscle sections were analyzed using hematoxylin and eosin staining as well as immunohistochemistry staining. The skeletal muscle cross-sectional area was significantly reduced in Klotho knockout mice and wild-type mice, aged 64 weeks, when compared with wild-type mice, aged 10 weeks, with a decreased percentage of type IIa and IIb myofibers. Likely impaired regenerative capacity, as reflected by the reduction of paired box 7 (Pax7)- and myogenic differentiation protein 1 (MyoD)-positive cells, was also observed in Klotho knockout mice and aged wild-type mice. 8-Hydroxy-2-deoxyguanosine expression was enhanced with Klotho knockout and aging, indicating higher oxidative stress. Adenosine A2B signaling was impaired, with a lower expression of the A2B receptor and the cAMP-response element binding protein in Klotho knockout and aged mice. The present study provides the novel finding that sarcopenia involves adenosine signaling under the influence of Klotho knockout.

A Multimodal Approach to Quantify Chondrocyte Viability for Airway Tissue Engineering

OBJECTIVES/HYPOTHESIS

Partially decellularized tracheal scaffolds have emerged as a potential solution for long-segment tracheal defects. These grafts have exhibited regenerative capacity and the preservation of native mechanical properties resulting from the elimination of all highly immunogenic cell types while sparing weakly immunogenic cartilage. With partial decellularization, new considerations must be made about the viability of preserved chondrocytes. In this study, we propose a multimodal approach for quantifying chondrocyte viability for airway tissue engineering.

METHODS

Tracheal segments (5 mm) were harvested from C57BL/6 mice, and immediately stored in phosphate-buffered saline at -20°C (PBS-20) or biobanked via cryopreservation. Stored and control (fresh) tracheal grafts were implanted as syngeneic tracheal grafts (STG) for 3 months. STG was scanned with micro-computed tomography (μCT) in vivo. STG subjected to different conditions (fresh, PBS-20, or biobanked) were characterized with live/dead assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and von Kossa staining.

RESULTS

Live/dead assay detected higher chondrocyte viability in biobanked conditions compared to PBS-20. TUNEL staining indicated that storage conditions did not alter the proportion of apoptotic cells. Biobanking exhibited a lower calcification area than PBS-20 in 3-month post-implanted grafts. Higher radiographic density (Hounsfield units) measured by μCT correlated with more calcification within the tracheal cartilage.

CONCLUSIONS

We propose a strategy to assess chondrocyte viability that integrates with vivo imaging and histologic techniques, leveraging their respective strengths and weaknesses. These techniques will support the rational design of partially decellularized tracheal scaffolds.

LEVEL OF EVIDENCE

N/A Laryngoscope, 133:512-520, 2023.

Skeletal muscle tissue composition ratio in patients with hip fracture: Comparison of fractured side and non-fractured side

BACKGROUND

The extent of asymmetry in the muscle tissue composition ratios with hip fractures has not been clarified.

OBJECTIVE

To determine whether there is a difference in the muscle tissue composition ratios between the fractured and non-fractured sides of the trunk and thighs immediate measurement.

METHODS

Forty-four patients (84.6 ± 7.0 years) were included. Computed tomography images were used for measurements. The muscle tissue composition ratio was measured using muscle cross-sectional area (CSA) and attenuation coefficient (Hounsfield units; HU). Defined each HU attenuation range as follows: low-density muscle (LDM), low-quality muscle tissue with fat infiltration, normal-density muscle (NDM), muscle contractor tissue, and intramuscular adipose tissue (IMAT), fat infiltration tissue. The CSA of each muscle tissue was expressed as a percentage: %LDM, %NDM, and %IMAT. A paired t-test was performed for comparison.

RESULTS

The %LDM on the fractured side was higher in the thigh and erector spinae. The %NDM on the fractured side was lower in the thigh. There was no significant difference in the %IMAT for all muscles.

CONCLUSION

The thigh on the fractured side showed asymmetry with low %NDM and high %LDM. This characteristic captures a characteristic of muscle tissue that may have importance in hip fracture etiology.

Impact of Change in Body Composition during Follow-Up on the Survival of GEP-NET

Background: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are heterogeneous rare diseases causing malnutrition and cachexia in which the study of body composition may have an impact in prognosis. Aim: Evaluation of muscle and fat tissues by computed tomography (CT) at the level of the third lumbar (L3 level) at diagnosis and at the end of follow-up in GET-NET patients and their relationships with clinical and biochemical variables as predictors of survival. Methodology: Ninety-eight GEP-NET patients were included. Clinical and biochemical parameters were evaluated. Total body, subcutaneous, visceral and total fat areas and very low-density, low-density, normal density, high-density, very high-density and total muscle areas were obtained from CT images. Results: Body composition measures and overall mortality correlated with age, ECOG (Eastern Cooperative Oncology Group performance status) metastases, lactate dehydrogenase (LDH), albumin and urea levels. Although there was no relationship between body composition variables at diagnosis and overall and specific mortality, an increase in low-density muscle and a decrease in normal-density muscle during follow-up were independently correlated to overall (p <0.05) and tumor-cause mortality (p < 0.05). Conclusion: Although body composition measures obtained by CT at diagnosis did not impact survival of GEP-NET patients, a loss of good quality muscle during follow-up was associated with an increased overall and tumor-related mortality. Nutritional status should therefore be supervised by nutrition specialists and an increase in good quality muscle could improve prognosis.

Early immunological responses to the mRNA SARS-CoV-2 vaccine in patients with neuromuscular disorders

Backgrounds

Intramuscular injection of the SARS-CoV-2 vaccine has raised concerns about its use in patients with neuromuscular disorders (NMDs). We evaluated the response of patients with NMDs to the BNT162b2 vaccine.

Methods

Healthy subjects, patients with spinal muscular atrophy (SMA), and patients with Duchenne muscular dystrophy (DMD) were included. All participants received two BNT162b2 doses. SARS-CoV-2 antibody titers at baseline and 2 weeks after each vaccination were compared between groups. Residual muscle volume was evaluated in NMDs group. A questionnaire documented adverse reactions.

Results

Eleven patients with NMDs (9 with SMA, 2 with DMD; 7 males; aged 32.7 ± 19.3 years) and 346 healthy subjects (60 males, aged 40.0 ± 12.4 years) were included. Antibody titers (U/mL) were similar between groups (baseline: <0.40 vs. <0.40, first vaccination, 145 ± 258 vs. 103 ± 1192, and second vaccination, 1528 ± 1265 vs. 1429 ± 944; p = 1.000, 0.909, and 0.736, respectively). A negative correlation was found between antibody titers and residual muscle volume but was not significant (Mercuri scale, r = −0.429, p = 0.249; fat infiltration rate, r = −0.194, p = 0.618). The adverse reactions were comparable between groups.

Conclusion

The BNT162b2 vaccine is safe and effective in patients with NMDs.

Impact of sarcopenia on tumor response and survival outcomes in patients with hepatocellular carcinoma treated by trans-arterial (chemo)-embolization

BACKGROUND

At the diagnosis of hepatocellular carcinoma (HCC), more than 90% of HCC patients present cirrhosis, a clinical condition often associated to malnutrition. Sarcopenia is an indirect marker of malnutrition assessable on computed tomography (CT).

AIM

To evaluate the prognostic value of sarcopenia in patients with HCC treated by trans-arterial (chemo)-embolization.

METHODS

Patients with HCC treated by a first session of trans-arterial (chemo)embolization and an available CT scan before treatment were included. Sarcopenia was assessed using skeletal muscle index at baseline and at the first radiological assessment. Radiological response was recorded after the first session of treatment using mRECIST.

RESULTS

Of 225 patients treated by trans-arterial bland embolization (n = 71) or trans-arterial chemoembolization (n = 154) for HCC between 2007 and 2013, Barcelona Clinic of Liver Cancer stage was A, B, and C in 27.5%, 55%, and 16.8% of cases, respectively. Sarcopenia was present in 57.7% of the patients. Patients with sarcopenia presented a higher rate of progressive disease (19% vs 8%, P = 0.0236), a shorter progression-free survival (8.3 vs 13.2 mo, P = 0.0035), and a shorter median overall survival (19.4 mo vs 35.5 mo, P = 0.0149) compared with non-sarcopenic patients. Finally, patients whose sarcopenia appeared after first transarterial treatment had the worst prognosis (P = 0.0004).

CONCLUSION

Sarcopenia is associated with tumor progression and poor survival outcomes after trans-arterial (chemo)-embolization for HCC.

Temporal Changes in Subcutaneous Fibrosis in Patients with Lower Extremity Lymphedema Following Surgery for Gynecologic Cancer: A Computed Tomography-Based Quantitative Analysis

Lymphedema causes inflammation, which provokes fibrosis within the epifascial tissue. Temporal change in fibrosis according to severity of the lymphedema has not been widely investigated. We aimed to study the quantitative changes in epifascial fibrosis during lymphedema treatment using computed tomography (CT). Forty-five patients (mean age: 57.75 ± 11.12 years) who developed lymphedema following gynecologic surgery were included in this retrospective study. Two weeks of complete decongestive therapy and continued self-bandaging or compression garments were prescribed under regular follow-up monitoring. Lower-extremity epifascial fibrosis was quantitatively analyzed on the initial and follow-up CT scans. Circumference, skin fibrosis, subcutaneous tissue, and fibrosis ratio were calculated in the axial scan. Based on the change in lymphedema severity, we divided subjects into ‘improved’ and ‘aggravated’ groups. The affected lower extremities showed higher circumference, more skin fibrosis and subcutaneous tissue, and higher fibrosis ratio than the unaffected sides on initial CT scan. At follow-up, compared to the aggravated group, the improved group showed significant decreases in fibrosis of skin and subcutaneous tissue and fibrosis ratio. Subcutaneous fibrosis was reversible with volume resolution of lymphedema. Therapeutic approaches should be established on the basis of the reversible nature of fibrotic changes in patients with lower extremity lymphedema.

Confocal and Super-Resolution Imaging of Polarized Intracellular Trafficking and Secretion of Basement Membrane Proteins During Drosophila Oogenesis

The basement membrane (BM) - a specialized sheet of extracellular matrix present at the basal side of epithelial cells - is critical for the establishment and maintenance of epithelial tissue morphology and organ morphogenesis. Moreover, the BM is essential for tissue modeling, serving as a signaling platform, and providing external forces to shape tissues and organs. Despite the many important roles that the BM plays during normal development and pathological conditions, the biological pathways controlling the intracellular trafficking of BM-containing vesicles and how basal secretion leads to the polarized deposition of BM proteins are poorly understood. The follicular epithelium of the Drosophila ovary is an excellent model system to study the basal deposition of BM membrane proteins, as it produces and secretes all major components of the BM. Confocal and super-resolution imaging combined with image processing in fixed tissues allows for the identification and characterization of cellular factors specifically involved in the intracellular trafficking and deposition of BM proteins. This article presents a detailed protocol for staining and imaging BM-containing vesicles and deposited BM using endogenously tagged proteins in the follicular epithelium of the Drosophila ovary. This protocol can be applied to address both qualitative and quantitative questions and it was developed to accommodate high-throughput screening, allowing for the rapid and efficient identification of factors involved in the polarized intracellular trafficking and secretion of vesicles during epithelial tissue development.

Skeletal muscle properties show collagen organization and immune cell content are associated with resistance exercise response heterogeneity in older persons

In older individuals, hypertrophy from progressive resistance training (PRT) is compromised in approximately one- third of participants in exercise trials. The objective of this study was to establish novel relationships between baseline muscle features and/or their PRT-induced change in vastus lateralis muscle biopsies with hypertrophy outcomes. Multiple linear regression analyses adjusted for sex were performed on phenotypic data from older adults (n=48, 70.8±4.5 years) completing 14 weeks of PRT. Results show that baseline muscle size associates with growth regardless of hypertrophy outcome measure (fiber cross-sectional area (fCSA), β=-0.76, Adj. p<0.01; thigh muscle area by CT, β=-0.75, Adj. p<0.01; DXA thigh lean mass, β=-0.47, Adj. p<0.05). Furthermore, loosely packed collagen organization (β=-0.44, Adj. p<0.05) and abundance of CD11b+/CD206- immune cells (β=-0.36, Adj. p=0.10) were negatively associated with whole muscle hypertrophy, with a significant sex interaction on the latter. Additionally, a composite hypertrophy score generated using all three measures reinforces significant fiber level findings that changes in myonuclei (β=0.67, Adj. p<0.01), changes in immune cells (β=0.48, Adj. p<0.05; both CD11b+/CD206+ and CD11b+/CD206- cells), and capillary density (β=0.56, Adj. p<0.01) are significantly associated with growth. Exploratory single cell RNA-sequencing of CD11b+ cells in muscle in response to resistance exercise showed that macrophages have a mixed phenotype. Collagen associations with macrophages may be an important aspect in muscle response heterogeneity. Detailed histological phenotyping of muscle combined with multiple measures of growth response to resistance training in older persons identify potential new mechanisms underlying response heterogeneity and possible sex differences.

Function Over Mass: A Meta-Analysis on the Importance of Skeletal Muscle Quality in COVID-19 Patients

COVID-19 caused by SARS-CoV-2 infection is a highly contagious disease affecting both the higher and lower portions of the respiratory tract. This disease reached over 265 million people and has been responsible for over 5.25 million deaths worldwide. Skeletal muscle quality and total mass seem to be predictive of COVID-19 outcome. This systematic review aimed at providing a critical analysis of the studies published so far reporting on skeletal muscle mass in patients with COVID-19, with the intent of examining the eventual association between muscle status and disease severity. A meta-analysis was performed to evaluate whether skeletal muscle quantity, quality and function were related to disease severity. Systematic reviews and meta-analyses were conducted according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions and reported according to the guidelines of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guide. From a total of 1,056 references found, 480 were selected after removing duplicates. Finally, only 7 met the specified inclusion criteria. The results of this meta-analysis showed that skeletal muscle quality, rather than quantity, was associated with COVID-19 severity, as confirmed by lower skeletal muscle density and lower handgrip strength in patients with severe disease. Muscle function assessment can thus be a valuable tool with prognostic value in COVID-19.

A reliable and robust method for the upper thigh muscle quantification on computed tomography: toward a quantitative biomarker for sarcopenia

Background

We aimed to evaluate the feasibility of the upper thigh level as a landmark to measure muscle area for sarcopenia assessment on computed tomography (CT).

Methods

In the 116 healthy subjects who performed CT scans covering from mid-abdomen to feet, the skeletal muscle area in the upper thigh level at the inferior tip of ischial tuberosity (SMA_UT), the mid-thigh level (SMA_MT), and L3 inferior endplate level (SMA_L3) were measured by two independent readers. Pearson correlation coefficients between SMA_UT, SMA_MT, and SMA_L3 were calculated. Inter-reader agreement between the two readers were evaluated using intraclass correlation coefficient (ICC) and Bland-Altman plots with 95% limit of agreement (LOA).

Results

In readers 1 and 2, very high positive correlations were observed between SMA_UT and SMA_MT (r = 0.91 and 0.92, respectively) and between SMA_UT and SMA_L3 (r = 0.90 and 0.91, respectively), while high positive correlation were observed between SMA_MT and SMA_L3 (r = 0.87 and 0.87, respectively). Based on ICC values, the inter-reader agreement was the best in the SMA_UT (0.999), followed by the SMA_L3 (0.990) and SMA_MT (0.956). The 95% LOAs in the Bland-Altman plots indicated that the inter-reader agreement of the SMA_UT (− 0.462 to 1.513) was the best, followed by the SMA_L3 (− 9.949 to 7.636) and SMA_MT (− 12.105 to 14.605).

Conclusion

Muscle area measurement at the upper thigh level correlates well with those with the mid-thigh and L3 inferior endpoint level and shows the highest inter-reader agreement. Thus, the upper thigh level might be an excellent landmark enabling SMA_UT as a reliable and robust biomarker for muscle area measurement for sarcopenia assessment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05032-2.

Computed Tomography-Based Quantitative Analysis of Fibrotic Changes in Skin and Subcutaneous Tissue in Lower Extremity Lymphedema Following Gynecologic Cancer Surgery

Background: Lymphedema produces protein-rich fluids that aggravate inflammation in the skin and subcutaneous tissue. Inflammation then induces fibroadipose tissue deposition and fibrosis. However, few methods have been developed to evaluate the severity of fibrosis. Therefore, we aimed to evaluate the subcutaneous fibrotic changes in lower extremity lymphedema following gynecologic cancer surgery using an image analysis tool, the FIJI software. Methods and Results: Seventy-four patients with lymphedema following gynecologic surgery were enrolled in this study. We quantitatively analyzed the cross-sectional area (CSA) of soft tissue compartments, including subcutaneous tissue with the skin, muscle volume, fibrotic changes in subcutaneous tissue, and the perimeter of skin boundaries. The limb circumference and the CSA of the subcutaneous tissue and skin on the affected side were significantly larger than those on the unaffected side. Fibrotic changes showed the same trend. However, muscle volume patterns were different from those of the other compartments. Some patients showed lower muscle volume on the unaffected side than on the affected side. Circumference and cellulitis significantly affected the extent of fibrotic changes in the skin and subcutaneous tissues. Age and duration of lymphedema did not affect fibrosis. Conclusion: Fibrosis of subcutaneous regions with the skin can be quantitatively calculated using an image analysis tool in lower extremity lymphedema following gynecologic cancer surgery. Edema and cellulitis increase fibrotic changes in the subcutaneous tissue with the skin.

Subcutaneous fat area at the upper thigh level is a useful prognostic marker in the elderly with femur fracture

BACKGROUND

The aim of this study was to evaluate prognostic value of body tissue composition at the upper thigh level for 1 year mortality in elderly patients with proximal femur fracture.

METHODS

This retrospective cohort study included consecutive elderly (aged ≥65) patients diagnosed with proximal femur fracture based on the findings of pelvic bone computed tomography (CT) performed at the emergency department of a tertiary care hospital and treated with surgery between 2010 and 2017. The cross-sectional area of subcutaneous fat and skeletal muscle at the upper thigh level was measured using CT. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for 1 year mortality were estimated using a Cox proportional hazards model. Survival based on the SFA quartiles was assessed using nonparametric Kaplan-Meier survival analysis and compared used log-rank tests.

RESULTS

Among 876 elderly patients included in this study, the median age was 79.0 years, and 646 (73.7%) patients were female. A total of 93 (10.6%) died within 1 year after admission to the emergency department. Survivors had a significantly higher median subcutaneous fat area (SFA) than non-survivors (170.2 vs. 133.0 cm² , P < 0.001), but no significant difference was observed between the skeletal muscle area (median, 156.7 vs. 160.3 cm² , P = 0.504) and muscle density (median, 19.0 vs. 19.1 HU, P = 0.861) of both groups. After adjustment of other clinical characteristics and body compositions, the multivariate Cox proportional hazard analysis showed that SFA (adjusted HR, 0.987; 95% CI, 0.982-0.992; P < 0.001) was independently associated with 1 year mortality. With 384 deaths during 51 322 person-months of follow-up, the median estimated survival duration of all the patients was 92.8 months (95% CI, 80.8-104.7 months). The patients with SFA in the third (165.6-195.0 cm² ) and fourth (>195.0 cm² ) quartiles showed significantly longer survival duration than those with SFA in the first (<131.4 cm² ; median survival time, 51.3 months) and second (131.4-165.5 cm² ; median survival time, 88.7 months) quartiles (P < 0.001 by log-rank test).

CONCLUSIONS

The SFAs measured at the upper thigh level and 1 year mortality are positively associated in elderly patients with proximal femur fracture. SFA may be an independent prognostic biomarker for 1 year mortality of femur fracture.

Construction and verification of an intelligent measurement model for diabetic foot ulcer

OBJECTIVES

The measurement of diabetic foot ulcers is important for the success in diabetic foot ulcer management. At present, it lacks the accurate and convenient measurement tools in clinical. In recent years, artificial intelligence technology has demonstrated the potential application value in the field of image segmentation and recognition. This study aims to construct an intelligent measurement model of diabetic foot ulcers based on the deep learning method, and to conduct preliminary verification.

METHODS

The data of 1 042 diabetic foot ulcers clinical samples were collected. The ulcers and color areas were manually labeled, of which 782 were used as the training data set and 260 as the test data set. The Mask RCNN ulcer tissue color semantic segmentation and RetinaNet scale digital scale target detection were used to build a model. The training data set was input into the model and iterated. The test data set was used to verify the intelligent measurement model.

RESULTS

This study established an intelligent measurement model of diabetic foot ulcers based on deep learning. The mean average precision@.5 intersection over union (mAP@.5IOU) of the color region segmentation in the training set and the test set were 87.9% and 63.9%, respectively; the mAP@.5IOU of the ruler scale digital detection in the training set and the test set were 96.5% and 83.4%, respectively. Compared with the manual measurement result of the test sample, the average error of the intelligent measurement result was about 3 mm.

CONCLUSIONS

The intelligent measurement model has good accuracy and robustness in measuring the diabetic foot ulcers. Future research can further optimize the model with larger-scale data samples.

Association Between the Normal-Density Psoas Muscle Index and Handgrip Strength or Gait Speed in Maintenance Hemodialysis Patients

Introduction: This study aimed to evaluate the association between the psoas muscle (PM) index with or without fatty infiltration and various indices associated with muscle mass in hemodialysis (HD) patients.

Methods: We included stable HD patients (n = 83). The collected data included subjective global assessment (SGA) score, ASM/Ht² (appendicular skeletal muscle mass divided by the squared height in meters), gait speed (GS; m/s), and handgrip strength (HGS; kg). The abdominal computed tomography (CT) image was obtained using a CT scanner. The PM and normal-density PM (NPM) indices (mm²/m²) were calculated using the whole PM area or the area with an attenuation range of 35–100 HU divided by the squared height in meters.

Results: Correlation coefficients for the SGA score, ASM/Ht², HGS, and GS were greater for the NPM index than for the PM index. The linear regression analysis showed that, on multivariate analysis, the NPM index was significantly associated with the SGA score, ASM/Ht², and GS. However, the PM index was significantly associated with the SGA score and ASM/Ht² but not with HGS or GS. For calculating the low GS, the area under the receiver operating characteristic curve area was significantly greater for the NPM index than for the PM index (P = 0.012).

Conclusion: The present study suggested that the NPM index excluding fatty infiltration may be an early and useful indicator for detecting muscle strength and physical performance among HD patients.

Inhibition of the canonical Wnt signaling pathway by a β-catenin/CBP inhibitor prevents heart failure by ameliorating cardiac hypertrophy and fibrosis

In heart failure (HF) caused by hypertension, the myocyte size increases, and the cardiac wall thickens. A low-molecular-weight compound called ICG001 impedes β-catenin-mediated gene transcription, thereby protecting both the heart and kidney. However, the HF-preventive mechanisms of ICG001 remain unclear. Hence, we investigated how ICG001 can prevent cardiac hypertrophy and fibrosis induced by transverse aortic constriction (TAC). Four weeks after TAC, ICG001 attenuated cardiac hypertrophy and fibrosis in the left ventricular wall. The TAC mice treated with ICG001 showed a decrease in the following: mRNA expression of brain natriuretic peptide (Bnp), Klf5, fibronectin, β-MHC, and β-catenin, number of cells expressing the macrophage marker CD68 shown in immunohistochemistry, and macrophage accumulation shown in flow cytometry. Moreover, ICG001 may mediate the substrates in the glycolysis pathway and the distinct alteration of oxidative stress during cardiac hypertrophy and HF. In conclusion, ICG001 is a potential drug that may prevent cardiac hypertrophy and fibrosis by regulating KLF5, immune activation, and the Wnt/β-catenin signaling pathway and inhibiting the inflammatory response involving macrophages.

Low Thoracic Skeletal Muscle Area Is Not Associated With Negative Outcomes in Patients With COVID-19

OBJECTIVE

Sarcopenia has been related to negative outcomes in different clinical scenarios from critical illness to chronic conditions. The aim of this study was to verify whether there was an association between low skeletal muscle index and in-hospital mortality, intensive care unit admission, and invasive mechanical ventilation need in hospitalized patients with COVID-19.

DESIGN

This was a retrospective cohort study of a referral center for COVID-19. We included all consecutive patients admitted to the hospital between February 26 and May 15, 2020, with a confirmed diagnosis of COVID-19. Skeletal muscle index was assessed from a transverse computed tomography image at the level of twelfth thoracic vertebra with National Institutes of Health ImageJ software, and statistical analysis was performed to find an association between skeletal muscle index and in-hospital mortality, need of invasive mechanical ventilation, and intensive care unit admission.

RESULTS

We included 519 patients, the median age was 51 (42-61) yrs, and 115 patients (22%) had low skeletal muscle index. On multivariable analysis, skeletal muscle index was not associated with mortality, intensive care unit admission, or invasive mechanical ventilation need nor in a subanalysis of patients 65 yrs or older.

CONCLUSIONS

Skeletal muscle index determined by computed tomography at the level of twelfth thoracic vertebra was not associated with negative outcomes in hospitalized patients with COVID-19.

Association of Creatinine-to-Cystatin C Ratio with Myosteatosis and Physical Performance in Older Adults: The Japan Shimanami Health Promoting Program

OBJECTIVE

Sarcopenia is a risk factor for poor outcomes in older adults. Identification of plasma markers may facilitate screening of sarcopenia. We previously reported that creatinine-to-cystatin C ratio is a simple marker of muscle mass. To further assess the clinical relevance of the creatinine-to-cystatin C ratio, we investigated its association with myosteatosis and physical performance.

DESIGN

Observational study.

SETTING AND PARTICIPANTS

Cross-sectional analysis of the dataset obtained from a Japanese population consisting of 1468 older (≥60 years of age) community residents.

METHODS

The mean attenuation values of the skeletal muscle calculated from computed tomography images of the midthigh were used as an index of myosteatosis, while the cross-sectional area of the muscle was used as a proxy for muscle mass. Physical performance was assessed by 1-leg standing time.

RESULTS

Creatinine-to-cystatin C ratio was positively associated with the cross-sectional area of muscle fiber-rich muscles, while it showed an inverse association with fat-rich muscle areas, resulting in the positive association between creatinine-to-cystatin C ratio and the mean attenuation value of the skeletal muscle [creatinine-to-cystatin C ratio quartiles (Q), Q1: 47.4 ± 4.8, Q2: 48.9 ± 4.4, Q3: 49.8 ± 4.1, Q4: 50.9 ± 3.7, P < .001]. The results of the linear regression analysis adjusted for major covariates (including muscle cross-sectional area) identified creatinine-to-cystatin C ratio as an independent determinant of the mean attenuation value (Q1: reference, Q2: β = 0.07, P = .019, Q3: β = 0.11, P < .001, Q4: β = 0.16, P < .001). Low creatinine-to-cystatin C ratio was independently associated with 1-leg standing time, although the association was attenuated substantially by adjusting for skeletal muscle cross-sectional area and mean attenuation value.

CONCLUSION AND IMPLICATIONS

Creatinine-to-cystatin C ratio was associated with myosteatosis in older adults, independent of the muscle mass. Creatinine-to-cystatin C ratio may serve as a convenient marker of sarcopenia.

Associations of muscle lipid content with physical function and resistance training outcomes in older adults: altered responses with metformin

Preserving muscle mass and strength is critical for long-term health and longevity. Age-related muscle lipid accumulation has been shown to be detrimental to muscle health. In healthy older individuals, we sought to determine whether muscle lipid content, determined from computed tomography, is associated with self-reported physical function, laboratory-measured performance, and the response to progressive resistance training (PRT), and how metformin may alter these responses (N = 46 placebo, 48 metformin). Using multiple linear regression models adjusted for confounders in a large cohort, we show that intermuscular adipose tissue (IMAT) was not associated with baseline function or response to PRT, contrary to previous reports. On the other hand, thigh muscle density (TMD), as an indicator of intra- and extramyocellular lipid (IMCL and EMCL), remained strongly and independently positively associated with physical function and performance following adjustment. Baseline TMD was inversely associated with gains in strength, independent of muscle mass. Percent change in TMD was positively associated with improved chair stand and increased type II fiber frequency but was not associated with muscle hypertrophy or overall strength gain following PRT. For the first time, we show that metformin use during PRT blunted density and strength gains by inhibiting fiber type switching primarily in those with low baseline TMD. These results indicate that participants with higher muscle lipid content derive the most performance benefit from PRT. Our results further indicate that muscle density may be as influential as muscle size for strength, physical function, and performance in healthy older adults. ClinicalTrials.gov , NCT02308228, Registered on 25 November 2014.

Characteristics of Lymphedema in Patients Treated with Mammalian Target of Rapamycin Inhibitors

Purpose: To investigate the characteristics of lymphedema in patients treated with mammalian target of rapamycin (mTOR) inhibitors and delineate complex decongestive therapy (CDT) outcomes. Methods and Results: We retrospectively analyzed 24 patients with mTOR inhibitor-induced lymphedema and 7 lymphedema patients (control) not treated with mTOR inhibitors, who visited the lymphedema clinic of the department of rehabilitation medicine from March 2016 to December 2019. We comprehensively reviewed clinical features, medication history, associated diseases, lymphoscintigraphy, lower extremity computed tomography venography (LE CTV), and the effect of CDT. By using ImageJ program, we measured the cross-sectional area (CSA) of muscle and subcutaneous fat of mid-thigh image in LE CTV and compared them to a control group not treated with mTOR inhibitors. Seventeen patients on sirolimus and seven patients on everolimus were included, with an approximately equal distribution of stages 2 and 3 lymphedema, and most with pitting edema. Ten patients had breast or gynecological cancer and underwent lymph node dissection. Lymphedema developed after mTOR inhibitor initiation, not postoperatively. Lymphoscintigraphy revealed decreased lymph node uptake and dermal backflow. LE CTV revealed subcutaneous honeycomb-shaped trabecular areas in the affected limbs of seven patients. Patients treated with mTOR inhibitors had a larger mean subcutaneous fat CSA and a smaller mean muscular CSA than controls. Lymphedema improved or remained unchanged after initial CDT. Daily CDT adequately controlled 11 cases, but exacerbation occurred in 5 of 7 poorly compliant patients, and cellulitis occurred in 6 patients. Conclusion: Physicians should identify mTOR inhibitor-related lymphedema early and discuss medication alternatives and CDT with patients.