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11.

Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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目的:观察平肝定眩汤对肝阳上亢型后循环缺血性眩晕的疗效。方法:选取2017年6月-2018年10月烟台业达医院收治的后循环缺血性眩晕的患者120例,按随机数字表法分为治疗组和对照组。治疗组和对照组各60例,两组一般的资料经统计学方法,差异无统计学意义(P>0.05),具有可比性。两组均给予改善循环,控制血压、血糖,调节血脂,抗血小板聚集等基础治疗。治疗组给予平肝定眩汤,对照组给予平眩胶囊。两组疗程均为4周,观察两组患者治疗前后总体症状,脑血流速度、血脂、血糖等指标改善情况。采用SPSS 11.0统计学软件进行计算。结果:治疗组总有效率91.7%(55/60),对照组总有效率61.6%(37/60),两组疗效比较有统计学意义(P<0.05)。治疗组三酰甘油(Triglyceride,TG)、血清总胆固醇(Serum Total Cholesterol,TC)、HDL-C、LDL-C治疗后显著改善,与治疗前比较,差异有统计学意义(P<0.05);对照组TG及TC治疗前后差异有统计学意义(P<0.05),高密度脂蛋白胆固醇(High Density Liptein Cholesterol,HDL-C)及低密度脂蛋白胆固醇(Low Density Liptein Cholesterol,LDL-C)治疗前后比较,差异无统计学意义(P>0.05)。两组治疗后TC比较,差异有统计学意义(P<0.05)。两组治疗后空腹血糖(Fasting Plasma Glucose,GLU)明显降低(P<0.05),两组间的治疗后比较,差异无统计学意义(P>0.05)。治疗组治疗后椎动脉(Vertebral Artery,VA)、基底动脉(Basilarartery,BA)平均血流速度(Mean Blood Flow Velocity,VM)明显提高,与对照组治疗后相比较,差异具有统计学意义(P<0.05)。结论:平肝定眩汤治疗后循环缺血性眩晕在改善患者症状、降低血液黏稠度,改善脑血流状况方面疗效显著。  相似文献   
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Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes.  相似文献   
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Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
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