背景 肌肉减少症是终末期肝病患者死亡的独立危险因素,与患者的预后密切相关,因此受到广泛关注.但对于肌少症来说,目前还缺乏统一的检测方法和诊断标准,临床应用受限.目的评估乙肝肝硬化相关慢加急性肝衰竭(acute-on-chronic liver failure,ACLF)患者的第三腰椎腰大肌指数(the third lumbar level psoas muscle index,L3-PMI)与临床指标的关系及其在预后评估中的作用.方法 采用回顾性研究的方法,选取2014-01/2017-12在天津市第三中心医院肝内科住院的符合乙肝肝硬化相关ACLF诊断标准且有腹部CT扫描资料的140例患者为研究对象.由同一名研究者在患者腹部CT图像上手动追踪第三腰椎下缘水平面,测量双侧腰大肌最大前后径和横径,计算腰大肌指数.分析患者的L3-PMI和临床特点及预后.结果 将140例患者按90天生存情况分为生存组102例,死亡组38例.死亡组患者L3-PMI值4.89 cm2/m2±1.42 cm2/m2较生存组患者5.94 cm2/m2±1.24 cm2/m2显著降低(P＜0.001);血小板(platelet,PLT)、白蛋白(albumin,ALB)、丙氨酸转移酶(alanine aminotransferase,ALT)、天门冬氨酸转移酶(aspartate transaminase,AST)、血肌酐(serum creatinine,SCr)、估算肾小球滤过率(estimated glomerular filtration rate,eGFR)在两组之间无统计学差异,P值均＞0.05;死亡组患者白细胞(white blood cell,WBC)、国际标准化比值(international normalized ratio,INR)水平、终末期肝病模型(model for end-stage liver disease,MELD)评分显著高于生存组,而血清钠显著低于生存组(P值均＜0.05).此外,ACLF患者中33例合并肝性脑病(hepatic encephalopathy,HE)的患者L3-PMI值5.17 cm2/m2±1.49 cm2/m2显著低于107例未合并HE的患者5.80 cm2/m2±1.29 cm2/m2,(P=0.02).所有ACLF患者中男性120例,女性20例,其中男性组L3-PMI值5.92 cm2/m2±1.23 cm2/m2显著高于女性组4.03 cm2/m2±0.92 cm2/m2,(P＜0.05).按性别分别绘制L3-PMI预测死亡的ROC曲线图,其中男性ROC曲线下面积0.726,截断值为5.02,敏感度为85％,特异度50％;女性ROC曲线下面积0.774,截断值为4.60,敏感度为50％,特异度100％.结论 L3-PMI对于评估乙肝肝硬化相关ACLF患者的预后有重要临床应用价值.

随着全球人口老龄化趋势的加剧,如何改善老年人口的生存质量成为一个全球性的公共卫生问题.肠道细菌作为人体最大的微生态系统,在衰老及相关疾病进程中起重要作用,日益受到临床医生关注.本文对肠道菌群与衰老相关疾病关系的国内外研究进展进行总结,并从影响老年人肠道菌群的因素、老年人肠道菌群变化的特点、肠道菌群代谢产物及其生理作用、肠道菌群代谢产物致病机制等方面进行综述,旨在为临床提供帮助.

OBJECTIVE: To investigate biological characteristics of human umbilical cord-derived mesenchymal stem cells, and to explore the possibility of hepatocyte-like cells differentiation.METHODS: The umbilical cord was provided by healthy term birth woman in Tianjin Third Central Hospital. Mesenchymal stem cells were isolated from human umbilical cord by enzyme digestion method. Cells were passaged at 80%-90% confluent. The ninth passage of cells at a density of 5×10~(10)/L were seeded in 12-well culture plate and incubated with DMEM containing hepatocyte growth factor, fibroblast growth factor-4 and oncostatin for 28 days. Cell growth activity was detected by MTT method; cell cycle was detected by flow cytometry; surface immunological marker in MSC was detected by immunocytochemical stain and flow cytometry; specific surface phenotype of hepatocyte was detected by immunocytochemical staining. Function characteristic of hepatocyte was determined by staining for glycogen.RESULTS: MSCs were isolated from human umbilical cord and presented with fibroblastic morphology. 80% of cells were at G_0/G_1 phase with good growth activity and stably passaged over 20 times. These cells were positive for CD29, CD105, and Vimentin, but negative for CD34 and CD31. MSCs were induced to hepatocyte-1 ike cells that were positive for alpha fetoprotein, CK18, CK19 at 1 week and albumin at 3 weeks. At 4 weeks, induced cells were positive for glycogen staining.CONCLUSION: MSCs isolated from human umbilical cord can be cultured in a long periods time in vitro and are able to differentiate into functional hepatocyte-like cells.

目的:研究脐带间充质干细胞（umbilical cord-mesenchymal stem cells,UC-MSCs）生物学的特性及向肝细胞分化的可能性.方法:从脐带中分离间充质干细胞,体外行传代培养,检测脐带间充质干细胞表面免疫标志、细胞周期和生长活性等,利用肝细胞生长因子、成纤维生长因子4和抑瘤素等细胞因子诱导脐带间充质干细胞向肝细胞分化,用免疫细胞方法对诱导和未诱导的细胞进行免疫学检测,糖原染色进行功能鉴定.结果:从人脐带中可分离到贴壁生长的间充质干细胞,细胞形态类似成纤维细胞,可在体外进行长期稳定培养;CD29、CD105和Vimentin表达阳性,基本不表达CD34、CD31,经加入细胞因子可成功将间充质干细胞向肝细胞诱导分化,分化的细胞表达肝细胞表面标志物ALB、AFP、CK18和CK19,糖原染色呈现阳性.结论:人脐带中可成功分离到间充质干细胞,细胞可实现体外长期培养,表达脐带间充质干细胞的表面标志,在体外脐带间充质干细胞诱导分化为肝细胞,有望成为细胞替代治疗的理想来源之一.