Objective To investigate the post-discharge exercise behavior and factors influencing moderate to vigorous intensity physical activity (MVPA) in patients undergoing lung surgery. Methods A total of 2874 patients from the large prospective, observational perioperative lung symptom study cohort (CN-PRO-Lung 3) in the Department of Thoracic Surgery at Sichuan Cancer Hospital between April 7, 2021, and January 31, 2024, were selected as the survey subjects. A survey was conducted using the Investigation of Exercise Behavior after Lung Surgery questionnaire and the International Physical Activity Questionnaire-Short Form (IPAQ-SF) among patients who underwent lung surgery. Binary logistic regression was used to analyze the factors influencing patients’ engagement in MVPA. Results A total of 702 patients were surveyed, including 252 males and 450 females, with an average age of (52.4±10.2) years. Patients with lung cancer accounted for 85.9%. Only 36.0% of the patients had regular exercise habits, while 42.3% did not engage in any physical activity. The three main barriers for postoperative exercise were physical discomfort (pain, coughing, shortness of breath, etc, 54.7%), lack of professional guidance (41.7%), and concerns about the surgical wound (28.9%). The proportions of patients engaging in vigorous, moderate, and low-intensity physical activity were 5.7%, 28.2%, and 66.1%, respectively. Multivariate analysis showed that patients with a personal annual income ≥50000 yuan (OR=1.52, 95%CI 1.01-2.29, P=0.044), high school education or above (OR=1.92, 95%CI 1.33-2.76, P<0.001), and lobectomy (OR=1.44, 95%CI 1.02-2.03, P=0.037) engaged in more MVPA. Conclusion Patients undergoing lung surgery have inadequate physical activity after discharge, particularly lacking in MVPA. Patients with higher income, higher educational levels, and lobectomy are more frequently engaged in MVPA. Measures such as symptom control, providing exercise guidance, and enhancing education on wound care may potentially improve the inadequate physical activity in lung surgery patients after discharge.

AIM To investigate the mechanism of Jiedu Yizhi Formula on cognitive function and neuroinflammation in a mouse model of Alzheimer's disease(AD).METHODS 50 APP/PS1 double transgenic mice were randomly divided into the model group,the donepezil group,and the low-dose,moderate-dose,and high-dose Jiedu Yizhi Formula group(1.78,3.56 and 7.12 g/kg),with 10 mice in each group,in contrast to the 10 WT mice of the blank group.Following anesthesia administration and 8-week oral gavage regimen with respective drugs,all mice underwent final tissue sample collection.The mice had their learning and memory ability assessed by Morris water maze and nesting behavior scores;their pathology of brain tissue and Aβ expression observed using HE,Nissl and IHC staining;their polarization of microglia and the expression of inflammatory factors in hippocampal tissue detected by IF and ELISA;their hippocampal expression of PI3K/Akt/mTOR signaling pathway detected by RT-qPCR and Western blot.RESULTS Compared with the blank group,the model group had lower scores in total swimming distance,frequency in crossing the platform,residence time in the target quadrant,and nesting behavior scores(P＜0.05,P＜0.01);prolonged evasion latency(P＜0.01);more disorganized arrangement of pyramidal cells,solidification and deep staining,unclear demarcation,irregular cell shapes,reduction of Nyctinidia,and increased Aβ deposition in the brain tissue(P＜0.01);elevated expression of hippocampal microglia M1-type markers CD16/32 and lba-1(P＜0.01);decreased levels of M2-type marker CD206(P＜0.05);elevated levels of TNF-α and IL-1β(P＜0.01);decreased expressions of IL-13 and IL-4(P＜0.01);and decreased levels of PI3K,Akt and mTOR mRNA,and reduced p-PI3K,p-Akt and p-mTOR protein expressions(P＜0.01).Compared to the model group,the donepezil group and the Jiedu Yizhi Formula groups showed statistically significant improvements in the aforementioned indexes(P＜0.05,P＜0.01),with the magnitude of improvement being higher in the high-dose Jiedu Yizhi Formula group.CONCLUSION Jiedu Yizhi Formula suppresses microglia Ml-type polarization while enhancing M2-type polarization via activation the PI3K/Akt/mTOR signaling pathway,which subsequently reduces inflammatory cytokine secretion.This mechanism attenuates Aβ deposition in brain tissues and ameliorates cognitive dysfunction in AD mouse models.

Objective:To investigate the change trend of hepatectomy for hepatocellular carcinoma and efficacy of fluorescent laparoscopic hepatectomy in a single center from 2014?2023.Methods:The propensity score matching and retrospective cohort study was conducted. The clinicopathological data of 17 232 patients of hepatocellular carcinoma who were admitted to Zhongshan Hospital of Fudan University from January 2014 to December 2023 were collected. There were 14 404 males and 2 828 females, aged 58(range, 11?94)years. Observation indicators: (1) change trend of hepatectomy for hepatocellular carcinoma and application of fluorescent laparoscopy in 2014?2023; (2) propensity score matching between patients undergoing fluorescent and conventional laparoscopic hepatectomy; (3) intraoperative and postoperative conditions of patients in the fluorescent laparoscopy group and the conventional laparoscopy group after propensity score matching. Comparison of measurement data with skewed distribution between groups was conducted using the Mann-Whitney U test. Comparison of count data between groups was conducted using the chi-square test. Comparison of ordinal data between groups was conducted using the nonparametic rank sum test. Propensity score matching was performed using the 1∶3 nearest neighbor matching method, with the caliper value of 0.01. Results:(1) Change trend of hepatectomy for hepatocellular carcinoma and application of fluorescent laparoscopy in 2014-2023. Among 17 232 patients of hepatocellular carcinoma, 4 074 cases underwent laparoscopic surgery, and 13 158 cases underwent open surgery or conversion from laparoscopic to open surgery. From 2014 to 2023, the proportions of laparos-copic surgery in hepatectomy were 8.993%(117/1 301), 6.804%(99/1 455), 9.379%(145/1 546), 17.511%(287/1 639), 23.828%(427/1 792), 24.572%(459/1 868), 29.662%(544/1 834), 31.568%(584/1 850), 38.080%(599/1 573), and 34.246%(813/2 374), respectively. The proportions of Grade Ⅲ surgery in laparoscopic hepatectomy were 11.966%(14/117), 7.071%(7/99), 12.414%(18/145), 21.254%(61/287), 28.337%(121/427), 27.887%(128/459), 34.375%(187/544), 34.644%(214/584), 35.726%(214/599), and 42.681%(347/813), respectively. From 2016 to 2023, the proportions of the application of fluorescent laparoscopy in laparoscopic hepatectomy were 2.069%(3/145), 5.923%(17/287), 8.431%(36/427), 10.022%(46/459), 17.647%(96/544), 24.829%(145/584), 9.182%(55/599), and 12.915%(105/813), respectively. (2) Propensity score matching between patients undergoing fluorescent and conventional laparoscopic hepatectomy. Among the 4 074 patients who underwent laparoscopic liver resection, 503 cases using fluorescent laparoscopy were assigned to the fluorescent laparoscopy group, 3 571 cases using conventional laparoscopy were assigned to the conventional laparoscopy group. A total of 1 794 patients were successfully matched, with 483 cases in the fluorescent laparoscopy group and 1 311 cases in the conventional laparoscopy group. After propensity score matching, the confounding biases of the maximum tumor diameter and the year of surgery were eliminated, and the two groups were comparable. (3) Intraoperative and postoperative conditions of patients in the fluorescent laparoscopy group and the conventional laparoscopy group after propensity score matching. After propensity score matching, there was no perioperative death in either the fluorescent laparoscopy group or the conventional laparoscopy group.The operation time of patients in the fluorescent laparoscopy group was 240(150,328)minutes, the portal triad clamping time was 30(15,45)minutes, the volume of intraoperative blood loss was 50(30,100)mL, the number of patients with complication 72, respectively. For patients in the conventional laparoscopy group, the above indicators were 180(131,240)minutes, 23(15,30)minutes, 55(50,100)mL, and 248, respectively. There were significant differences in the above indicators between the two groups ( Z=?7.593, ?7.372, ?4.941, χ2=3.873, P<0.05). Conclusion:The proportion and difficulty level of laparoscopic hepatectomy for hepatocellular carcinoma in Zhongshan Hospital of Fudan University have shown an upward trend during 2014?2023. Compared with conventional laparoscopy, patients undergoing fluorescent laparoscopic hepatectomy have longer operation time and portal triad clamping time, but less intraoperative blood loss and lower iproportion of complications.

Objective To explore the optimal warning threshold of motor evoked potentials(MEP)in decompression surgery for ossification of the posterior longitudinal ligament(OPLL)at cervical and thoracic segments,and the predictive role of different MEP parameters on postoperative lower extremity motor function.Methods A retrospective analysis was conducted on the clinical data of 227 patients diagnosed with cervical or thoracic OPLL and underwent decompression surgery from January 2022 to January 2024 in the hospital.There were 131 males and 96 females,with an average age of(60±10)years.All patients underwent continuous neuro-physiological monitoring during the operation,and the minimum ratio of MEP amplitude change to the baseline at the beginning of the operation(Dmax)and the ratio of MEP terminal amplitude change to the baseline at the end of the operation(Dend)were recorded.The correlations between these two ratios and the lower extremity motor func-tion immediately after the operation and at 1 year were compared.According to the Medical Research Council muscle strength score(MRC)standard,a postoperative score increase of≥1 point compared to preoperative was defined as postoperative motor dysfunction.Pearson correlation coefficients were used to evaluate the correlations between Dmax and Dend and the lower extremity motor function immediately after the operation and at 1 year.Receiver operating characteristic(ROC)curves were drawn to predict postoperative lower extremity motor dysfunc-tion using Dmax and Dend.Results Among the 227 patients,186 had cervical OPLL and 41 had thoracic OPLL.The incidence of lower extremity motor dysfunction immediately after the operation and at 1 year was 7 cases(3.76%)and 2 cases(1.08%)in the cervical group,and 9 cases(21.95%)and 3 cases(7.32%)in the thoracic group,respectively.The incidence of lower extremity motor dysfunction in the thoracic group was higher than that in the cervical group(P<0.001).The baseline induction rate of bilateral lower extremity MEPs was 98.92%(368/372)in the cervical group and 96.34%(79/82)in the thoracic group.The Pearson correlation coefficients of Dend with the bilateral lower extremity motor function immediately after the operation in the cervical and thoracic groups were both greater than those of Dmax,and the differences were statistically significant(cervical group:r=0.669,0.517,P=0.001 2;thoracic group:r=0.882,0.727,P=0.003 6),while the differences in the Pearson corre-lation coefficients of Dend and Dmax with the bilateral lower extremity motor function at 1 year were not statistically significant(cervical group:r=0.457,0.352,P=0.088;thoracic group:r=0.760,0.625,P=0.098).The cut-off values of Dend for the cervical group were 0.853 immediately after the operation and at 1 year,and the cut-off values of Dmax were 0.881 and 0.978,respectively.For the thoracic group,the cut-off values of Dend were 0.532 immediately after the operation and 0.639 at 1 year,and the cut-off values of Dmax were 0.532 and 0.640,respec-tively.Conclusions In OPLL surgery,the MEP monitoring strategy should be adjusted according to the surgical segment.For the cervical segment,Dmax should be emphasized to balance high sensitivity and specificity,while for the thoracic segment,Dmax or Dend can be flexibly selected.Higher MEP warning thresholds are required for cervical OPLL surgery(Dmax:0.881 immediately after the operation and 0.978 at 1 year;Dend:0.853),while significantly lower thresholds are needed for thoracic OPLL(Dmax/Dend:0.532 immediately after the operation and 0.640 at 1 year).

BACKGROUND:Dexamethasone and hindlimb suspension are commonly used methods for modeling sarcopenia in animal experiments due to their short modeling time,ease of operation,and low cost.OBJECTIVE:To compare the differences in muscle mass,strength and functional phenotypes and molecular mechanisms between two mouse sarcopenia models induced by dexamethasone and hindlimb suspension.METHODS:Thirty male C57BL/6 mice were randomly divided into three groups(n=10 per group).The normal control group received no intervention.The dexamethasone group received daily intraperitoneal injections of 1 mg/kg/d dexamethasone sodium phosphate solution for 6 continuous days to establish sarcopenia models in mice,while mice in the hindlimb suspension group were suspended by tail harness for 16 hours,once per day,to establish sarcopenia models.Within 6 weeks after modeling,changes in body mass were monitored.After 6 weeks of modeling,mice were tested for limb grip strength,mobility(swimming test),skeletal muscle wet mass,and skeletal muscle pathological morphology.Expressions of skeletal muscle protein synthesis and catabolism indexes as well as the AMPK/FoXO3α signaling pathway were detected by RT-PCR and western blot.RESULTS AND CONCLUSION:(1)Two weeks after modeling,both dexamethasone and hindlimb suspension groups showed a significant decrease in body mass compared with the normal control group(P<0.001).After 6 weeks of modeling,grip strength of mice in both dexamethasone and hindlimb suspension groups was lower than that in the normal control group(P<0.001).The wet mass of gastrocnemius and extensor digitorum longus muscles and the cross-sectional area of gastrocnemius and soleus muscles in the dexamethasone group were lower than those in the normal control group(P<0.05).Compared with the hindlimb suspension group,the cross-sectional area of gastrocnemius muscle was significantly smaller in the dexamethasone group(P<0.05),while the cross-sectional area of soleus muscle was larger in the dexamethasone group(P<0.05).Mice in the dexamethasone group had reduced mobility when compared with those in the normal control group and the hindlimb suspension group(P<0.05).(3)Compared with the normal control group,PI3K,mTOR,AMPK,and PGC-1α mRNA expression and P-AMPK/AMPK protein were decreased in the two modeling groups(P<0.05),and FoXO3α mRNA expression and PGC-1α and FoXO3 protein expression were elevated(P<0.05);in the dexamethasone group,Akt1 mRNA expression was decreased(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was elevated(P<0.05);in the hindlimb suspension group,Akt1 mRNA expression was elevated(P<0.05).(4)Compared with the dexamethasone group,mTOR,Akt1,and FoXO3α mRNA expression was elevated in the hindlimb suspension group(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was decreased(P<0.05).To conclude,both modeling methods could decrease the levels of mitochondrial energy metabolism in skeletal muscle,with the dexamethasone group mediating atrophy of skeletal muscle through the dual action of ubiquitin proteasome and energy metabolism pathways,and the hindlimb suspension group inducing atrophy of skeletal muscle by mediating the energy metabolism pathway through the AMPK/FoXO3α signaling pathway,subsequently causing a reduction in mass,strength,and function of skeletal muscle.

AIM To compare total sugar,total protein,total phenol,total flavonoid,calycosin-7-O-β-D-glucoside,liquiritin,lobetyolin,quercetin,isoferulic acid,hesperidin,glycyrrhizic acid contents and their antioxidant activities,hypoglycemic activities of big honey pill,small honey pill,water pill,concentrated pill,granule,mixture and decoction of Buzhong Yiqi Recipe.METHODS Anthraquinone-sulfuric acid method,Coomassie brilliant blue method,Folin-phenol colorimetry method,sodium nitrite-aluminum nitrate method and HPLC were adopted in the content determination of total sugar,total protein,total phenol,total flavonoid and seven constituents,respectively,after which the scavenging capacities,reducing powers on DPPH·free radical,ABTS+free radical,hydroxyl free radical,and inhibition capacity on α-glucosidase activity were detected.Subsequently,correlation analysis was performed.RESULTS Total sugar,total protein,total phenol and total flavonoid contents demonstrated significant differences among different dosage forms(P＜0.05,P＜0.01).Calycosin-7-O-β-D-glucoside,glycyrrhizin,codonoside and quercetin displayed the highest contents in the decoction,while those of isoferulic acid,hesperidin and glycyrrhizin were observable in the mixture.The water pill exhibited the strongest antioxidant activity,while those of the concentrated pill and mixture were weak;the big honey pill exhibited the strongest hypoglycemic activity,while that of the decoction was the weakest.Total protein,total phenol,total flavonoid and liquiritin contents displayed significant positive correlations between antioxidant activity(P＜0.05,P＜0.01),while hesperidin content displayed significant negative correlation between the latter(P＜0.05);total protein,calycosin-7-O-β-D-glucoside,codonoside and quercetin contents displayed significant negative correlations between hypoglycemic activity(P＜0.05,P＜0.01).CONCLUSION Active constituent contents and their biological activities of Buzhong Yiqi Recipe with different dosage forms exist differences,total sugar,total protein,total flavonoids,calycosin-7-O-β-D-glucoside,licorice glycoside,hesperidin,codonoside and quercetin can be taken as quality control indices for this prescription.

AIM To investigate the mechanism of Jiedu Yizhi Formula on cognitive function and neuroinflammation in a mouse model of Alzheimer's disease(AD).METHODS 50 APP/PS1 double transgenic mice were randomly divided into the model group,the donepezil group,and the low-dose,moderate-dose,and high-dose Jiedu Yizhi Formula group(1.78,3.56 and 7.12 g/kg),with 10 mice in each group,in contrast to the 10 WT mice of the blank group.Following anesthesia administration and 8-week oral gavage regimen with respective drugs,all mice underwent final tissue sample collection.The mice had their learning and memory ability assessed by Morris water maze and nesting behavior scores;their pathology of brain tissue and Aβ expression observed using HE,Nissl and IHC staining;their polarization of microglia and the expression of inflammatory factors in hippocampal tissue detected by IF and ELISA;their hippocampal expression of PI3K/Akt/mTOR signaling pathway detected by RT-qPCR and Western blot.RESULTS Compared with the blank group,the model group had lower scores in total swimming distance,frequency in crossing the platform,residence time in the target quadrant,and nesting behavior scores(P＜0.05,P＜0.01);prolonged evasion latency(P＜0.01);more disorganized arrangement of pyramidal cells,solidification and deep staining,unclear demarcation,irregular cell shapes,reduction of Nyctinidia,and increased Aβ deposition in the brain tissue(P＜0.01);elevated expression of hippocampal microglia M1-type markers CD16/32 and lba-1(P＜0.01);decreased levels of M2-type marker CD206(P＜0.05);elevated levels of TNF-α and IL-1β(P＜0.01);decreased expressions of IL-13 and IL-4(P＜0.01);and decreased levels of PI3K,Akt and mTOR mRNA,and reduced p-PI3K,p-Akt and p-mTOR protein expressions(P＜0.01).Compared to the model group,the donepezil group and the Jiedu Yizhi Formula groups showed statistically significant improvements in the aforementioned indexes(P＜0.05,P＜0.01),with the magnitude of improvement being higher in the high-dose Jiedu Yizhi Formula group.CONCLUSION Jiedu Yizhi Formula suppresses microglia Ml-type polarization while enhancing M2-type polarization via activation the PI3K/Akt/mTOR signaling pathway,which subsequently reduces inflammatory cytokine secretion.This mechanism attenuates Aβ deposition in brain tissues and ameliorates cognitive dysfunction in AD mouse models.

This study was aimed at exploring novel auxiliary diagnostic biomarkers for brucellosis and their potential miR-NA-mRNA regulatory networks.High-throughput sequencing was used to compare miRNA expression differences in serum ex-osomes between patients with brucellosis and healthy controls.Subsequently,RT-qPCR was used to validate the expression of significantly upregulated exosomal miRNAs.The diagnostic value of these miRNAs was assessed with ROC curves,and bioin-formatics analyses were performed to investigate the potential roles of the miRNAs in brucellosis infection.The ROC curve a-nalysis indicated that the area under the curve for exosomal hsa-miR-11400(P＜0.05),hsa-miR-199a-5p(P＜0.05),and hsa-miR-148a-5p(P＜0.05)was 0.79,0.81,and 0.74,respectively.A total of 465 differentially expressed miRNAs and their tar-get genes were predicted,including 25 immune-related target genes,most of which were closely associated with cancer-related proteoglycans,NF-kappa B signaling pathways,and IL-17 signaling pathways.The constructed differentially expressed gene network indicated that the immune genes PLXNA2,IL17RA,PRKCA,CD22,ACVR1B,and CBL might be regulated by hsa-miR-199a-5p and hsa-miR-148a-5p.These findings suggest that exosomal miRNAs might serve as auxiliary diagnostic indicators for brucellosis.Our exosomal miRNA-mRNA regulatory network provides new insights into the pathogenesis and treatment of brucellosis.

This study was aimed at exploring novel auxiliary diagnostic biomarkers for brucellosis and their potential miR-NA-mRNA regulatory networks.High-throughput sequencing was used to compare miRNA expression differences in serum ex-osomes between patients with brucellosis and healthy controls.Subsequently,RT-qPCR was used to validate the expression of significantly upregulated exosomal miRNAs.The diagnostic value of these miRNAs was assessed with ROC curves,and bioin-formatics analyses were performed to investigate the potential roles of the miRNAs in brucellosis infection.The ROC curve a-nalysis indicated that the area under the curve for exosomal hsa-miR-11400(P＜0.05),hsa-miR-199a-5p(P＜0.05),and hsa-miR-148a-5p(P＜0.05)was 0.79,0.81,and 0.74,respectively.A total of 465 differentially expressed miRNAs and their tar-get genes were predicted,including 25 immune-related target genes,most of which were closely associated with cancer-related proteoglycans,NF-kappa B signaling pathways,and IL-17 signaling pathways.The constructed differentially expressed gene network indicated that the immune genes PLXNA2,IL17RA,PRKCA,CD22,ACVR1B,and CBL might be regulated by hsa-miR-199a-5p and hsa-miR-148a-5p.These findings suggest that exosomal miRNAs might serve as auxiliary diagnostic indicators for brucellosis.Our exosomal miRNA-mRNA regulatory network provides new insights into the pathogenesis and treatment of brucellosis.

BACKGROUND:Dexamethasone and hindlimb suspension are commonly used methods for modeling sarcopenia in animal experiments due to their short modeling time,ease of operation,and low cost.OBJECTIVE:To compare the differences in muscle mass,strength and functional phenotypes and molecular mechanisms between two mouse sarcopenia models induced by dexamethasone and hindlimb suspension.METHODS:Thirty male C57BL/6 mice were randomly divided into three groups(n=10 per group).The normal control group received no intervention.The dexamethasone group received daily intraperitoneal injections of 1 mg/kg/d dexamethasone sodium phosphate solution for 6 continuous days to establish sarcopenia models in mice,while mice in the hindlimb suspension group were suspended by tail harness for 16 hours,once per day,to establish sarcopenia models.Within 6 weeks after modeling,changes in body mass were monitored.After 6 weeks of modeling,mice were tested for limb grip strength,mobility(swimming test),skeletal muscle wet mass,and skeletal muscle pathological morphology.Expressions of skeletal muscle protein synthesis and catabolism indexes as well as the AMPK/FoXO3α signaling pathway were detected by RT-PCR and western blot.RESULTS AND CONCLUSION:(1)Two weeks after modeling,both dexamethasone and hindlimb suspension groups showed a significant decrease in body mass compared with the normal control group(P<0.001).After 6 weeks of modeling,grip strength of mice in both dexamethasone and hindlimb suspension groups was lower than that in the normal control group(P<0.001).The wet mass of gastrocnemius and extensor digitorum longus muscles and the cross-sectional area of gastrocnemius and soleus muscles in the dexamethasone group were lower than those in the normal control group(P<0.05).Compared with the hindlimb suspension group,the cross-sectional area of gastrocnemius muscle was significantly smaller in the dexamethasone group(P<0.05),while the cross-sectional area of soleus muscle was larger in the dexamethasone group(P<0.05).Mice in the dexamethasone group had reduced mobility when compared with those in the normal control group and the hindlimb suspension group(P<0.05).(3)Compared with the normal control group,PI3K,mTOR,AMPK,and PGC-1α mRNA expression and P-AMPK/AMPK protein were decreased in the two modeling groups(P<0.05),and FoXO3α mRNA expression and PGC-1α and FoXO3 protein expression were elevated(P<0.05);in the dexamethasone group,Akt1 mRNA expression was decreased(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was elevated(P<0.05);in the hindlimb suspension group,Akt1 mRNA expression was elevated(P<0.05).(4)Compared with the dexamethasone group,mTOR,Akt1,and FoXO3α mRNA expression was elevated in the hindlimb suspension group(P<0.05),while Atrogin-1 and MuRF-1 mRNA expression was decreased(P<0.05).To conclude,both modeling methods could decrease the levels of mitochondrial energy metabolism in skeletal muscle,with the dexamethasone group mediating atrophy of skeletal muscle through the dual action of ubiquitin proteasome and energy metabolism pathways,and the hindlimb suspension group inducing atrophy of skeletal muscle by mediating the energy metabolism pathway through the AMPK/FoXO3α signaling pathway,subsequently causing a reduction in mass,strength,and function of skeletal muscle.