Phase angle and its determinants among adolescents: influence of body composition and physical fitness level.

To examine the association between levels of physical fitness, parameters of body composition and phase angle (PhA) amongst adolescents. A total of 152 adolescents (84 girls) aged 11-16 years were included in this study. Weight and height were measured and the body mass index (BMI) was calculated. Bioelectrical impedance analysis (BIA) provided resistance and reactance parameters to calculate fat-free mass (FFM), PhA and fat mass (%FM). The following physical fitness variables were analysed: flexibility, abdominal muscular endurance, upper and lower limb explosive strength, agility, speed and cardiorespiratory fitness. Generalized Linear Models were applied to verify differences across sexes. Stepwise linear regression was used to establish an association between the variables studied. The study established an association between PhA and weight, FFM, BMI, FM, %FM and medicine ball throw (MBT) for girls. As for the boys, an association was verified between PhA and weight, FFM, BMI, standing long jump (SLJ), MBT and the three allometric VO2peak variables analyzed. An association was found between PhA and the boys' 4-m shuttle run test (4SRT) and 20-m sprint test (20SRT). Boys showed a greater phase angle than girls; In girls, BMI and %FM, were determinant of 32.4% (r = 0.57). PhA variability which is influenced by physical fitness, body composition and, therefore, the tissues electrical conductivity. Furthermore, boys' height, FFM, upper limb strength, and agility account for 58.4% (r = 0.76) PhA variability. There was a positive correlation between the physical fitness tests and the PhA.

[Relationship between bioelectrical impedance analysis-derived fluid status and nutritional indicators and the prognosis in patients undergoing maintenance hemodialysis].

Objective: To explore the relationship between bioelectrical impedance analysis (BIA)-derived fluid status and nutritional indicators and the prognosis in patients undergoing maintenance hemodialysis (MHD). Methods: A retrospective cohort study was conducted. The clinical data of MHD patients in Jiangsu Province Hospital between January 2014 and December 2016 were analyzed. BIA data of healthy volunteers in Gulou District, Nanjing City, collected between April and October 2022, were used to determine the cut-off value of body cell mass index (BCMI). Referring to previous research, using 0.15 as the cut-off value for the ratio of overhydration and extracellular water (OH/ECW). The data were transformed into binary variables based on these cut-off values to categorize patients into different groups. Kaplan-Meier analysis was used to plot survival curves, and the Cox proportional hazards model was performed to analyze risk factors for all-cause mortality. Results: A total of 706 MHD patients (407 males and 299 females) were included, aged (54±15) years. MHD patients were classified into four groups based on whether BCMI was<5.4 kg/m2 and OH/ECW was≥0.15, which included non-overhydration and non-malnutrition group, overhydration group, malnutrition group, and overhydration and malnutrition group, with 269, 186, 151, and 100 patients, respectively. During a median follow-up of [M(Q1, Q3)] 33 (26, 37) months, 162 patients died. Kaplan-Meier analysis showed that the median survival periods of the four groups were 52 months (95%CI: 41-54 months), 46 months (95%CI: 44-49 months), 37 months (95%CI: 34-40 months), and 34 months (95%CI: 30-38 months), respectively, with a statistically significant difference (P<0.001). The 1-year survival rates were 95.5%, 93.5%, 92.1%, and 88.0% (P<0.001), respectively, and the 2-year mortality rates were 92.6%, 87.1%, 83.4%, and 77.0% (P<0.001), respectively. Multivariate Cox regression analysis showed that compared with non-overhydration and non-malnutrition group, the risk of all-cause mortality increased by 1.18 times in the malnutrition group (HR=2.18, 95%CI: 1.29-3.71, P=0.004), and by 1.59 times in the overhydration and malnutrition group (HR=2.59, 95%CI: 1.48-4.54, P=0.001). Conclusions: BIA-derived fluid status and nutritional indicators are associated with the prognosis of MHD patients. Compared with patients without fluid overload and malnutrition, patients with malnutrition and fluid overload have an increased risk of all-cause mortality.

Effect of measurement procedure errors on assessing lung fluid via remote dielectric sensing system.

The study assessed the impact of procedural errors on the remote dielectric sensing system (ReDS), a non-invasive lung fluid assessment technology, in an Asian cohort. Healthy volunteers underwent ReDS measurements following manufacturer's instructions, with two consecutive measurements one minute apart. A subset of 20 participants had modified procedure settings. Reliability was measured using intraclass correlation coefficient (ICC). The study included 86 healthy volunteers, and all ReDS measurements fell within the recommended normal range. The intra-rater reliability of ReDS measurements was excellent, with an ICC of 0.968. Among the subset of 20 subjects, deviations in height and weight did not significantly affect ReDS values. However, deviations in chest size by ± 3 cm had a noticeable impact on ReDS measures, and incorrect station selection led to fluctuations in ReDS readings. In conclusion, the ReDS system demonstrated excellent intra-rater reliability and applicability in an Asian cohort. Procedural errors, such as chest size measurement and station selection, significantly influenced ReDS measurements. Adherence to standardized operating procedures is crucial to ensure accurate and consistent results. These findings highlight the importance of adherence to manufacturer instructions when utilizing ReDS for lung fluid assessment, thereby enhancing its reliability and clinical applicability.

Postural balance and functional mobility in relation to BMI and body composition among female students at a College of Applied Medical Sciences: A cross-sectional study.

INTRODUCTION: This study aimed to compare different Body Mass Index (BMI) categories, body composition parameters, postural balance, and functional mobility among female students at a College of Applied Medical Sciences; and examine the relationship between BMI and body composition with postural balance and functional mobility among female students at the college of applied medical sciences. MATERIALS AND METHODS: Female students, aged 18‒25 years old. They were subdivided into four groups according to their BMI category: underweight, normal, overweight, or obese, with n = 20 participants in each group. A Bioelectrical Impedance Human Body Analyzer (BIA) was used to assess the following body composition parameters: Fat Percentage (FATP), fat mass, muscle mass, and Total Body Water (TBW). A NeuroCom Balance Master was used to assess postural balance and functional mobility. A Timed Up and Go (TUG) test was employed to assess functional mobility. All data were analyzed using SPSS. RESULTS: Participants' ages and heights were matched (p > 0.05). However, there were variables that were statistically significantly higher in terms of weight, BMI and body composition, including FATP, fat mass, muscle mass, and TBW (p = 0.000), among the obese group. Moreover, postural balance was lower among the obese group. There was a significant relationship between BMI and body composition variables in respect of postural balance but not in relation to functional mobility. CONCLUSION: Postural instability but not functional mobility was related to higher BMI and body composition values among the study groups.

Concordance between platelet counts by impedance and optical technique during microcytic anemia: towards a threshold value of the mean corpuscular volume.

INTRODUCTION: Platelet count is crucial for clinical decision. In cases of microcytosis, platelet count based on impedance technique (PLT-I) may overestimate platelet count. AIM: To compare PLT-I with platelet count using the optical technique (PLT-O) and establish a Mean Corpuscular Volume (MCV) threshold for considering PLT-O. METHODS: A prospective analytical study conducted over two months involved blood samples collected in standard K2 EDTA tubes for complete blood count analysis, revealing microcytosis (MCV<80 fL). PLT-O analysis in channel-Ret mode was performed using the Sysmex-XN1000 (Sysmex Corporation, Kobe, Japan). Percentage of fragmented red cells (FRC%) and percentage of microcytic red cells (Micro-R%) were recorded. Blood smears stained with May-Grünwald-Giemsa were examined for potential interfering particles. RESULTS: A strong correlation was observed between the two techniques for all platelet values as well as for PLT <150 x 109/L (correlation coefficient r = 0.971, 95% CI: [0.956-0.982]; P<10-3 and r = 0.90, 95% CI: [0.79-0.95]; P< 10-3). The Bland-Altman plot revealed a bias of 16.53 x 109/L between the two methods, with agreement limits between -55.8 and 88.8 x 109/L. A threshold MCV value indicating the use of the optical method, with a cut-off at 72.9fL, demonstrated promising performance consistent with literature findings. However, less favorable performance was observed with Micro-R%. CONCLUSION: Impedance could be employed in routine practice. However, for MCV<72.9 fL or in the presence of schizocytes, the hemogram validation procedure may incorporate the use of PLT-O.

Non-invasive hERG channel screening based on electrical impedance tomography and extracellular voltage activation (EIT-EVA).

hERG channel screening has been achieved based on electrical impedance tomography and extracellular voltage activation (EIT-EVA) to improve the non-invasive aspect of drug discovery. EIT-EVA screens hERG channels by considering the change in extracellular ion concentration which modifies the extracellular resistance in cell suspension. The rate of ion passing in cell suspension is calculated from the extracellular resistance Rex, which is obtained from the EIT measurement at a frequency of 500 kHz. In the experiment, non-invasive screening is applied by a novel integrated EIT-EVA printed circuit board (PCB) sensor to human embryonic kidney (HEK) 293 cells transfected with the human ether-a-go-go-related gene (hERG) ion channel, while the E-4031 antiarrhythmic drug is used for hERG channel inhibition. The extracellular resistance Rex of the HEK 293 cells suspension is measured by EIT as the hERG channels are activated by EVA over time. The Rex is reconstructed into extracellular conductivity distribution change Δσ to reflect the extracellular K+ ion concentration change Δc resulting from the activated hERG channel. Δc is increased rapidly during the hERG channel non-inhibition state while Δc is increased slower with increasing drug concentration cd. In order to evaluate the EIT-EVA system, the inhibitory ratio index (IR) was calculated based on the rate of Δc over time. Half-maximal inhibitory concentration (IC50) of 2.7 nM is obtained from the cd and IR dose-response relationship. The IR from EIT-EVA is compared with the results from the patch-clamp method, which gives R2 of 0.85. In conclusion, EIT-EVA is successfully applied to non-invasive hERG channel screening.

Local vaginal bioelectrical impedance can predict preterm delivery in mice.

Preterm birth is a serious pregnancy complication that affects neonatal mortality, morbidity, and long-term neurological prognosis. Predicting spontaneous preterm delivery (PTD) is important for its management. While excluding the risk of PTD is important, identifying women at high risk of PTD is imperative for medical intervention. Currently used PTD prediction parameters in clinical practice have shown high negative predictive values, but low positive predictive values. We focused on sulfated and sialylated glycocalyx changes in the uterus and vagina prior to the onset of parturition and explored the potential of electrophysiological detection of these changes as a PTD prediction parameter with a high positive predictive value. In vivo local vaginal bioelectrical impedance (VZ) was measured using two different mouse PTD models. PTD was induced in ICR mice through the subcutaneous injection of mifepristone or local intrauterine injection of lipopolysaccharide (LPS). The PTD rates were 100% and 60% post-administration of mifepristone (16-20 h, n = 4) and LPS (12-24 h, n = 20), respectively. The local VZ values (15 and 10 h after mifepristone or LPS treatment, respectively) were significantly lower in the PTD group than in the non-PTD group. Receiver operator characteristic (ROC) curve analysis of VZ at 125 kHz as a predictor of PTD showed an area under the ROC curve of 1.00 and 0.77 and positive predictive values of 1.00 and 0.86, for the mifepristone and LPS models, respectively, suggesting that local VZ value can predict PTD. Histological examination of the LPS-treated model 6 h post-treatment revealed increased expression of sulfomucins and/or sulfated proteoglycans and sialomucins in the cervical epithelium, cervical stroma and vaginal stroma. In conclusion, local VZ values can determine sulfated and sialylated glycocalyx alterations within the uterus and vagina and might be a useful PTD prediction parameter.

How to diagnose GERC more effectively: reflections on post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance.

INTRODUCTION: Post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI) are novel parameters reflect esophageal clearance capacity and mucosal integrity. They hold potential in aiding the recognition of gastroesophageal reflux-induced chronic cough (GERC). Our study aims to investigate their diagnostic value in GERC. METHODS: This study included patients suspected GERC. General information and relevant laboratory examinations were collected, and final diagnosis were determined following guidelines for chronic cough. The parameters of multichannel intraluminal impedance-pH monitoring (MII-pH) in patients were analyzed and compared to explore their diagnostic value in GERC. RESULTS: A total of 186 patients were enrolled in this study. The diagnostic value of PSPWI for GERC was significant, with the area under the working curve (AUC) of 0.757 and a cutoff value of 39.4%, which was not statistically different from that of acid exposure time (AET) (p > 0.05). The combined diagnostic value of AET > 4.4% and PSPWI < 39.4% was superior to using AET > 4.4% alone (p < 0.05). Additionally, MNBI and distal MNBI also contributed to the diagnosis of GERC, with AUC values of 0.639 and 0.624, respectively. AET > 4.4% or PSPWI < 39.4% is associated with a 44% reduction in missed diagnoses of non-acid GERC compared to AET > 6.0% or symptom association probability (SAP) ≥ 95%, and may be more favorable for identifying GERC. CONCLUSION: The diagnostic value of PSPWI for GERC is comparable to that of AET. Combining PSPWI < 39.4% or AET > 4.4% can improve the diagnostic efficiency by reducing the risk of missed diagnoses in cases where non-acid reflux is predominant. Distal MNBI and MNBI can serve as secondary reference indices in the diagnosis of GERC.

Ultrasound Cut-Off Values for Rectus Femoris for Detecting Sarcopenia in Patients with Nutritional Risk.

BACKGROUND: A nationwide, prospective, multicenter, cohort study (the Disease-Related caloric-protein malnutrition EChOgraphy (DRECO) study) was designed to assess the usefulness of ultrasound of the rectus femoris for detecting sarcopenia in hospitalized patients at risk of malnutrition and to define cut-off values of ultrasound measures. METHODS: Patients at risk of malnutrition according to the Malnutrition Universal Screening Tool (MUST) underwent handgrip dynamometry, bioelectrical impedance analysis (BIA), a Timed Up and Go (TUG) test, and rectus femoris ultrasound studies. European Working Group on Sarcopenia in Older People (EWGSOP2) criteria were used to define categories of sarcopenia (at risk, probable, confirmed, severe). Receiver operating characteristic (ROC) and area under the curve (AUC) analyses were used to determine the optimal diagnostic sensitivity, specificity, and predictive values of cut-off points of the ultrasound measures for the detection of risk of sarcopenia and probable, confirmed, and severe sarcopenia. RESULTS: A total of 1000 subjects were included and 991 of them (58.9% men, mean age 58.5 years) were evaluated. Risk of sarcopenia was detected in 9.6% patients, probable sarcopenia in 14%, confirmed sarcopenia in 9.7%, and severe sarcopenia in 3.9%, with significant differences in the distribution of groups between men and women (p < 0.0001). The cross-sectional area (CSA) of the rectus femoris showed a significantly positive correlation with body cell mass of BIA and handgrip strength, and a significant negative correlation with TUG. Cut-off values were similar within each category of sarcopenia, ranging between 2.40 cm2 and 3.66 cm2 for CSA, 32.57 mm and 40.21 mm for the X-axis, and 7.85 mm and 10.4 mm for the Y-axis. In general, these cut-off values showed high sensitivities, particularly for the categories of confirmed and severe sarcopenia, with male patients also showing better sensitivities than women. CONCLUSIONS: Sarcopenia in hospitalized patients at risk of malnutrition was high. Cut-off values for the better sensitivities and specificities of ultrasound measures of the rectus femoris are established. The use of ultrasound of the rectus femoris could be used for the prediction of sarcopenia and be useful to integrate nutritional study into real clinical practice.

MXene-Based Flexible Electrodes for Electrophysiological Monitoring.

The advancement of flexible electrodes triggered research on wearables and health monitoring applications. Metal-based bioelectrodes encounter low mechanical strength and skin discomfort at the electrode-skin interface. Thus, recent research has focused on the development of flexible surface electrodes with low electrochemical resistance and high conductivity. This study investigated the development of a novel, flexible, surface electrode based on a MXene/polydimethylsiloxane (PDMS)/glycerol composite. MXenes offer the benefit of featuring highly conductive transition metals with metallic properties, including a group of carbides, nitrides, and carbonitrides, while PDMS exhibits inherent biostability, flexibility, and biocompatibility. Among the various MXene-based electrode compositions prepared in this work, those composed of 15% and 20% MXene content were further evaluated for their potential in electrophysiological sensing applications. The samples underwent a range of characterization techniques, including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), as well as mechanical and bio-signal sensing from the skin. The experimental findings indicated that the compositions demonstrated favorable bulk impedances of 280 and 111 Ω, along with conductivities of 0.462 and 1.533 mS/cm, respectively. Additionally, they displayed promising electrochemical stability, featuring charge storage densities of 0.665 mC/cm2 and 1.99 mC/cm2, respectively. By conducting mechanical tests, Young's moduli were determined to be 2.61 MPa and 2.18 MPa, respectively. The composite samples exhibited elongation of 139% and 144%, respectively. Thus, MXene-based bioelectrodes show promising potential for flexible and wearable electronics and bio-signal sensing applications.

Stability Study of Synthetic Diamond Using a Thermally Controlled Biological Environment: Application towards Long-Lasting Neural Prostheses.

This paper demonstrates, for the first time, the stability of synthetic diamond as a passive layer within neural implants. Leveraging the exceptional biocompatibility of intrinsic nanocrystalline diamond, a comprehensive review of material aging analysis in the context of in-vivo implants is provided. This work is based on electric impedance monitoring through the formulation of an analytical model that scrutinizes essential parameters such as the deposited metal resistivity, insulation between conductors, changes in electrode geometry, and leakage currents. The evolution of these parameters takes place over an equivalent period of approximately 10 years. The analytical model, focusing on a fractional capacitor, provides nuanced insights into the surface conductivity variation. A comparative study is performed between a classical polymer material (SU8) and synthetic diamond. Samples subjected to dynamic impedance analysis reveal distinctive patterns over time, characterized by their physical degradation. The results highlight the very high stability of diamond, suggesting promise for the electrode's enduring viability. To support this analysis, microscopic and optical measurements conclude the paper and confirm the high stability of diamond and its strong potential as a material for neural implants with long-life use.

Enhanced Sweat Biosensing with Thread-Embedded Microfluidic Devices.

BACKGROUND This study explored the integration of conductive threads into a microfluidic compact disc (CD), developed using the xurographic method, for a potential sweat biosensing platform. MATERIAL AND METHODS The microfluidic CD platform, fabricated using the xurographic method with PVC films, included venting channels and conductive threads linked to copper electrodes. With distinct microfluidic sets for load and metering, flow control, and measurement, the CD's operation involved spinning for sequential liquid movement. Impedance analysis using HIOKI IM3590 was conducted for saline and artificial sweat solutions on 4 identical CDs, ensuring reliable conductivity and measurements over a 1 kHz to 200 kHz frequency range. RESULTS Significant differences in |Z| values were observed between saline and artificial sweat treatments. 27.5 µL of saline differed significantly from 27.5 µL of artificial sweat, 72.5 µL of saline from 72.5 µL of artificial sweat, and 192.5 µL of saline from 192.5 µL of sweat. Significant disparities in |Z| values were observed between dry fibers and Groups 2, 3, and 4 (varying saline amounts). No significant differences emerged between dry fibers and Groups 6, 7, and 8 (distinct artificial sweat amounts). These findings underscore variations in fiber characteristics between equivalent exposures, emphasizing the nuanced response of the microfluidic CD platform to different liquid compositions. CONCLUSIONS This study shows the potential of integrating conductive threads in a microfluidic CD platform for sweat sensing. Challenges in volume control and thread coating degradation must be addressed for transformative biosensing devices in personalized healthcare.

Colonic Epithelial Permeability to Ions Is Restored after Vedolizumab Treatment and May Predict Clinical Response in Inflammatory Bowel Disease Patients.

Vedolizumab (VDZ) is used for treating inflammatory bowel disease (IBD) patients. A study investigating colonic epithelial barrier function ex vivo following VDZ is lacking. This work aims to evaluate ex vivo the colonic epithelial barrier function in IBD patients at baseline and during VDZ treatment, and to investigate the relationships between barrier function and clinical parameters. Colonic specimens were obtained from 23 IBD patients before, and at 24 and 52 weeks after VDZ treatment, and from 26 healthy volunteers (HV). Transepithelial electrical resistance (TEER, permeability to ions) and paracellular permeability were measured in Ussing chambers. IBD patients showed increased epithelial permeability to ions (TEER, 13.80 ± 1.04 Ω × cm2 vs. HV 20.70 ± 1.52 Ω × cm2, p < 0.001) without changes in paracellular permeability of a 4 kDa probe. VDZ increased TEER (18.09 ± 1.44 Ω × cm2, p < 0.001) after 52 weeks. A clinical response was observed in 58% and 25% of patients at week 24, and in 62% and 50% at week 52, in ulcerative colitis and Crohn's disease, respectively. Clinical and endoscopic scores were strongly associated with TEER. TEER < 14.65 Ω × cm2 predicted response to VDZ (OR 11; CI 2-59). VDZ reduces the increased permeability to ions observed in the colonic epithelium of IBD patients before treatment, in parallel to a clinical, histological (inflammatory infiltrate), and endoscopic improvement. A low TEER predicts clinical response to VDZ therapy.

Bioelectrical impedance parameters add incremental value to waist-to-hip ratio for prediction of metabolic dysfunction associated steatotic liver disease in youth with overweight and obesity.

Introduction: Metabolic dysfunction-associated steatotic liver disease (MASLD) presents a growing health concern in pediatric populations due to its association with obesity and metabolic syndrome. Bioelectrical impedance analysis (BIA) offers a non-invasive and potentially effective alternative for identifying MASLD risk in youth with overweight or obesity. Therefore, this study aimed to assess the utility of BIA for screening for MASLD in the youth. Method: This retrospective, cross-sectional study included 206 children and adolescents aged <20 years who were overweight and obese. The correlations between anthropometric measurements and BIA parameters and alanine aminotransferase (ALT) levels were assessed using Pearson's correlation analysis. Logistic regression analysis was performed to examine the associations between these parameters and ALT level elevation and MASLD score. Receiver operating characteristic (ROC) curves were generated to assess the predictive ability of the parameters for MASLD. Results: Pearson's correlation analysis revealed that waist-to-hip ratio (WHR), percentage body fat (PBF), and BIA parameters combined with anthropometric measurements were correlated with ALT level. Logistic regression revealed that WHR, skeletal muscle mass/WHR, PBF-WHR, fat-free mass/WHR, and appendicular skeletal muscle mass/WHR were correlated with ALT level elevation after adjusting for age, sex, and puberty. WHR, PBF-WHR, and visceral fat area (VFA)-WHR were positively correlated with the MASLD score in the total population after adjusting for age, sex, and puberty. PBF-WHR and VFA-WHR were correlated with the MASLD score even in youth with a normal ALT level. The cutoff points and area under the ROC curves were 34.6 and 0.69 for PBF-WHR, respectively, and 86.6 and 0.79 for VFA-WHR, respectively. Discussion: This study highlights the utility of combining BIA parameters and WHR in identifying the risk of MASLD in overweight and obese youth, even in those with a normal ALT level. BIA-based screening offers a less burdensome and more efficient alternative to conventional MASLD screening methods, facilitating early detection and intervention in youth at risk of MASLD.

Evaluation of the SARC-F Questionnaire as a Diagnostic Tool for Sarcopenia in Geriatric Age-group in India.

INTRODUCTION: With medical science advancing in leaps and bounds, average lifespan is now trending upward, and we are now facing an increasing prevalence of diseases of the elderly, sarcopenia being one of them. Unfortunately, sarcopenia, especially in India, remains to be frequently overlooked, underdiagnosed, and largely understudied. One of the greatest hindrances to the diagnosis of sarcopenia is high costs and limited availability of diagnostic modalities such as magnetic resonance imaging (MRI) and dual energy X-ray absorptiometry (DEXA) scan. Accessible, feasible, and affordable means to diagnose sarcopenia is thus the need of the hour. MATERIALS AND METHODS: We performed a cross-sectional observational study among 300 patients aged 65 years or above (including both outpatient and inpatient departments) at MM Institute of Medical Sciences, Mullana between June 2021 and June 2022. Patients were evaluated as per the European Working Group for Sarcopenia in Older People (EWGSOP) algorithm using bioelectrical impedance analysis (BIA) and the results were compared with results of the SARC-F questionnaire. Statistical analyses were then carried out using IBM Statistical Package for the Social Sciences (SPSS) Statistics version 26. RESULTS: Out of 300 patients, 56 (18.7%) were sarcopenic. Sarcopenia showed no significant association with sex (p = 0.74). SARC-F showed a sensitivity of 73.2% and a specificity of 37.3% with a positive predictive value of 86.51% and a negative predictive value of 32.84% in diagnosing sarcopenia. SARC-F showed good internal reliability with a Cronbach's α > 0.7. CONCLUSION: The SARC-F questionnaire can be used as a bedside screening tool for sarcopenia, especially in a developing country like India where diagnostic resources are frequently scarce.

Circulating myostatin as a biomarker of muscle mass and strength in individuals with cancer or obesity.

BACKGROUND & AIMS: Our study aims to determine whether myostatin (MSTN) is associated with muscle mass and strength in individuals with cancer or obesity, as well as with cancer cachexia (CC) or sarcopenic obesity (SO). METHODS: The ACTICA study included individuals with CC (n = 70) or without CC (NC, n = 73). The MYDIASECRET study included individuals with obesity evaluated before (T0) and 3 months (T3) after bariatric surgery (n = 62). Body composition was assessed using bioelectrical impedance analysis (BIA). Skeletal muscle mass (SMM) and appendicular SMM (ASMM) were calculated from Janssen's and Sergi's equations, respectively, and expressed as indexes (SMMI and ASMMI). Handgrip strength (HGS) was assessed using a Jamar hand-held dynamometer. MSTN plasma levels were measured using ELISA. Spearman's coefficient was used to correlate MSTN with muscle mass and strength. Receiver operating characteristic (ROC) curve analysis was performed to identify an optimal MSTN cutoff level for the prediction of CC or SO. RESULTS: In the ACTICA study, muscle mass and strength were lower in CC individuals than in NC individuals (SMMI: 8.0 kg/m2vs 9.0 kg/m2, p = 0.004; ASMMI: 6.2 kg/m2vs 7.2 kg/m2, p < 0.001; HGS: 28 kg vs 38 kg, p < 0.001). MSTN was also lower in CC individuals than in NC individuals (1434 pg/mL vs 2149 pg/mL, p < 0.001). Muscle mass and strength were positively correlated with MSTN (SMMI: R = 0.500, p < 0.001; ASMMI: R = 0.479, p < 0.001; HGS: R = 0.495, p < 0.001). ROC curve analysis showed a MSTN cutoff level of 1548 pg/mL (AUC 0.684, sensitivity 57%, specificity 75%, p < 0.001) for the prediction of CC. In the MYDIASECRET study, muscle mass and strength were reduced at T3 (SMMI: -8%, p < 0.001; ASMMI: -12%, p < 0.001; HGS: -6%, p = 0.005). MSTN was also reduced at T3 (1773 pg/mL vs 2582 pg/mL, p < 0.001). Muscle mass and strength were positively correlated with MSTN at T0 and T3 (SMMI-T0: R = 0.388, p = 0.002; SMMI-T3: R = 0.435, p < 0.001; HGS-T0: R = 0.337, p = 0.007; HGS-T3: R = 0.313, p = 0.013). ROC curve analysis showed a MSTN cutoff level of 4225 pg/mL (AUC 0.835, sensitivity 98%, specificity 100%, p = 0.014) for the prediction of SO at T3. CONCLUSIONS: MSTN is positively correlated with muscle mass and strength in individuals with cancer or obesity, suggesting its potential use as a biomarker of muscle mass and strength. The ROC curve analysis suggests the potential use of MSTN as a screening tool for CC and SO.

Performance of anthropometry-based and bio-electrical impedance-based muscle-mass indicators in the Global Leadership Initiative on Malnutrition criteria for predicting prognosis in patients with cancer.

BACKGROUND: Reduced muscle mass is a criterion for diagnosing malnutrition using the Global Leadership Initiative on Malnutrition (GLIM) criteria; however, the choice of muscle-mass indicators within the GLIM criteria remains contentious. This study aimed to establish muscle-measurement-based GLIM criteria using data from bio-electrical impedance analysis (BIA) and anthropometric evaluations and evaluate their ability to predict overall survival (OS), short-term outcomes, and healthcare burden in patients with cancer. METHODS: This was a multicenter, prospective study that commenced in 2013 and enrolled participants from various clinical centers across China. We constructed GLIM criteria based on various muscle measurements, including fat-free mass index (FFMI), skeletal muscle index (SMI), calf circumference (CC), midarm circumference (MAC), midarm muscle circumference (MAMC), and midarm muscle area (MAMA). Survival was estimated using the Kaplan-Meier method and survival curves were compared using the log-rank test. Cox proportional hazards regression was used to assess the independent association between the GLIM criteria and OS. The discriminatory performance of different muscle-measurement-based GLIM criteria for mortality was evaluated using Harrell's concordance index (C-index). Logistic regression was used to evaluate the association of the GLIM criteria with short-term outcomes and healthcare burden. RESULTS: A total of 4769 patients were included in the analysis, of whom 1659 (34.8%) died during the study period. The Kaplan-Meier curves demonstrated that all muscle-measurement-based GLIM criteria significantly predicted survival in patients with cancer (all p < 0.001). The survival rate of malnourished patients was approximately 10% lower than that of non-malnourished patients. Cox proportional hazards regression showed that all the muscle-measurement-based GLIM could independently predict the OS of patients (all p < 0.001). The prognostic discrimination was as follows: MAMC (Chi-square: 79.61) > MAMA (Chi-square: 79.10) > MAC (Chi-square: 64.09) > FFMI (Chi-square: 62.33) > CC (Chi-square: 58.62) > ASMI (Chi-square: 57.29). In comparison to the FFMI-based GLIM criteria, the ASMI-based criteria (-0.002, 95% CI: -0.006 to 0.002, p = 0.334) and CC-based criteria (-0.003, 95% CI: -0.007 to 0.002, p = 0.227) did not exhibit a significant advantage. However, the MAC-based criteria (0.001, 95% CI: -0.003 to 0.004, p = 0.776), MAMA-based criteria (0.004, 95% CI: 0.000-0.007, p = 0.035), and MAMC-based criteria (0.005, 95% CI: 0.000-0.007, p = 0.030) outperformed the FFMI-based GLIM criteria. Logistic regression showed that muscle measurement-based GLIM criteria predicted short-term outcomes and length of hospital stay in patients with cancer. CONCLUSION: All muscle measurement-based GLIM criteria can effectively predict OS, short-term outcomes, and healthcare burden in patients with cancer. Anthropometric measurement-based GLIM criteria have potential for clinical application as an alternative to BIA-based measurement.

Evaluating Dielectric Properties for Assessing Water Content at Acupuncture Points: New Methodology.

Importance: Understanding acupuncture point microenvironments is vital for optimizing treatment efficacy. Evaluating changes in water content at these points can provide further insights into the effects of acupuncture on tissues. Objective: This study aimed to measure tissue dielectric constant (TDC) and assess changes in water content, specifically at stomach 36 (ST36, Zusanli) and spleen 6 (SP6, Sanyinjiao) acupuncture points. Methods: In a controlled, blinded, randomized trial, 113 healthy volunteers were divided into six groups based on TDC sensor diameters (XS, M, and L): three control groups and three acupuncture groups. They were assessed at three time points: T1, baseline; T2, 20 min post-needle withdrawal; and T3, 40 min post-needle withdrawal. Electrical impedance (EI) was also analyzed. Significance level was set at p < 0.001. Results: TDC at ST36 and SP6 significantly decreased with the XS probe at T2 and T3 compared with that at T1 (F8, 452: 54.61). TDC did not significantly vary between T2 and T3 with M and L probes. EI data indicated that the current passage increased in the SP (F2, 226: 39.32) and ST (F2, 226: 37.32) groups during T2 and T3 compared with that during T1 within their respective groups and controls. Conclusions: and Relevance: This study demonstrated the efficacy of TDC measurements in detecting water content fluctuations at acupuncture points and their responses to needles. TDC measurements, which were validated against EI, provide valuable insights into acupuncture point microenvironments and thus help optimize treatments.

Volume control strategy and patient survival in sepsis-associated acute kidney injury receiving continuous renal replacement therapy: a randomized controlled trial with secondary analysis.

Optimal strategy for volume control and the clinical implication of achieved volume control are unknown in patients with sepsis-associated acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT). This randomized controlled trial aimed to compare the survival according to conventional or bioelectrical impedance analysis (BIA)-guided volume control strategy in patients with sepsis-associated AKI receiving CRRT. We also compared patient survival according to achieved volume accumulation rate ([cumulative fluid balance during 3 days × 100]/fluid overload measured by BIA at enrollment) as a post-hoc analysis. We randomly assigned patients to conventional volume control strategy (n = 39) or to BIA-guided volume control strategy (n = 34). There were no differences in 28-day mortality (HR, 1.19; 95% CI, 0.63-2.23) or 90-day mortality (HR, 0.99; 95% CI 0.57-1.75) between conventional and BIA-guided volume control group. In the secondary analysis, achieved volume accumulation rate was significantly associated with patient survival. Compared with the achieved volume accumulation rate of ≤ - 50%, the HRs (95% CIs) for the risk of 90-day mortality were 1.21 (0.29-5.01), 0.55 (0.12-2.48), and 7.18 (1.58-32.51) in that of - 50-0%, 1-50%, and > 50%, respectively. Hence, BIA-guided volume control in patients with sepsis-associated AKI receiving CRRT did not improve patient outcomes. In the secondary analysis, achieved volume accumulation rate was associated with patient survival.