Objective To summarize the recent progress in research on the mechanism of denerved skeletal muscle atrophy. Methods The recently-publ ished l iteratures at home and abroad on denerved skeletal muscle atrophy were reviewedand summarized. Results The mechanism of denerved skeletal muscle atrophy was very complex. At present, the studyof the mechanism was based on the changes in histology, cytology and molecules. Fiber thinning and disorderly arrangement of denerved skeletal muscles were observed and apoptotic bodies were detected. Apoptosis-promoting genes expressed upregulatedly and apoptosis-restraining genes expressed down-regulatedly. Muscle satell ite cells increased after denervation, but then they decreased and disappeared because they could not differentiate to mature muscle fibers. The structural change of cytomiscrosome and down-regulation of metabol ism-related enzymes induced cell metabol ism disorder. Conclusion The histological change of skeletal muscle fibers, the change of the number of muscle satell ite cells and differentiation, the structural change of cytomiscrosome and the change of apoptosis-related and metabol ism-related gene expressions contribute to denerved skeletal muscle atrophy.
ObjectiveTo investigate the possible mechanism affecting liver cirrhosis by splenectomy. MethodsBy subcutaneous administration of 20% carbon tetrachloride(CCl4), liver cirrhosis models were established in splenectomy and nonsplenectomy groups. After HE staining, special staining and immunohistochemical staining, mast cell, Kupffer’s cell and Ito cell were counted under optical microscope. Liver pathological sections and the dynamic changes of these cells in mice were studied respectively in comparison with the normal group.ResultsThe incidence of liver cirrhosis in nonsplenectomy group was significantly higher than that in splenectomy group after the 16th injection of CCl4 (P＜0.05). The count of mast cell was much higher than that in splenectomy group after the 4th and the 8th injection (P＜0.05). Kupffer’s cell and Ito cell significantly increased after the 12th and the 16th injection in nonsplenectomy group compared with splenectomy group (P＜0.05). ConclusionSplenectomy may decline the incidence of hepatic cirrhosis caused by multifactors. In the early stage, splenectomy influences the migration, maturation and accumulation of mast cell. In the middle and late stage, it influences the proliferation of Kupper’s cell and cytokine secretion, thus the Ito cells are activated and proliferation is inhibited, in which extracellular matrix decreases in amount and the degree of hepatic fibrosis is reduced.
The sample size of a meta-analysis should not be less than a single randomized controlled trial. Trial sequential analysis (TSA) can provide required information size and monitoring boundary to justify the conclusion of meta-analysis. However, the TSA software is only suitable for binary and continuous data, and it cannot analyze the time-to-event data. This paper aimed to introduce how to analyze the time-to-event data using TSA approach.