ABSTRACT
The outbreak of COVID-19 around the world has made more than two millions of confirmed patients and serious shortages of healthcare resources and medical staff in many countries. In the battle of fighting COVID-19 in Wuhan, many microsurgery staff across China were sent to Wuhan and put on duty in the treatment of COVID-19 patients. The purpose of this article is to review the personal experiences of microsurgery staff in fighting against COVID-19 as well as to analyse how to act professionally when facing the challenges and change of roles and meanwhile having to give full play to the professional advantages subject to make contributions to the battle of COVID-19. A reference is hereby provided for the microsurgery staff in dealing with a sudden and major epidemic outbreak in the future.
ABSTRACT
ObjectiveTo investigate expression of TGF-β1,CTGF and collagen deposition in skeletal muscle during chronic entrapment of peripheral nerve. MethodsFifty rats were separated into two groups,control group and experimental group. At different time points after operation, the right gastrocnemius of 5rats from each group were collected for further analysis such as HE, Masson stain, immunohistochemical staining,RT-PCR and Western-blot. Results It was observed that axon degeneration occurred during chronic nerve entrapment,and which was in line with reports from other groups.Moreover,it had been demonstrated that after nerve entrapment,skeletal muscles may form fibrosis and degeneration consequently.Within this pathological procedure,expression of TGF-β1. CTGF and deposition of collagenⅠ changed rapidly when compared with control group.ConclusionOverall,these results indicated that these factors may be important during skeletal muscle degeneration after chronic nerve entrapment.
ABSTRACT
In order to investigate the biological function of transforming growth factor-β1 (TGF-β1) during fibrosis in denervated skeletal muscle, we recruited sciatic nerve injury model of SD rats in which denervated gastrocnemius was isolated for analysis. At different time points after operation, denervated muscle was examined by several methods. Masson trichrome staining showed morphological changes of denervated skeletal muscle. Quantitative RT-PCR detected the rapid increase of TGF-β1 expression at mRNA level after nerve injury. It was found that a peak of TGF-β1 mRNA expression appeared one week post-operation. The expression of collagen I (COL I) mRNA was up-regulated in the nerve injury model as well, and reached highest level two weeks post-injury. Immunoblot revealed similar expression pattern of TGF-β1 and COL I in denervated muscles at protein level. In addition, we found that the area of the gastrocnemius muscle fiber was decreased gradually along with increased interstitital fibrosis. Interestingly, this pathological change could be prevented, at least partly, by local injection of TGF-β1 antibodies, which could be contributed to the reduced production of COL I by inhibiting function of TGF-β1. Taken together, in this study, we demonstrated that the expression of TGF-β1 was increased significantly in denervated skeletal muscle, which might play a crucial role during muscle fibrosis after nerve transection.
ABSTRACT
Adult stem cells from skeletal muscle cells were induced to differentiate into cardiocytes to see if stem cells from another different but histologically-comparable tissues can differentiate to the target cells. Skeletal muscles-derived stem cells (MDSCs) were isolated from adult skeleton muscle tissues by differential adhesion, and immunocytochemically identified by using Sca-1. In order to induce the proliferation but not differentiation of MDSCs, the cells were cultured in Dulbecco's modified Eagle's medium/F12 (DMEM/F12) supplemented with 1:50 B27, 20 ng/mL basic fibroblast growth factor (bFGF), 20 ng/mL epidermal growth factor (EGF) in a suspension for 6 days. Then these stem cells were treated with 5 mumol/L 5-azacytidine for 24 h in an adherence culture. The characteristics of induced cells were examined by immunocytochemistry, quantitative real time RT-PCR and morphological observation of cell phenotype. Our results showed that the appearance of some cells gradually changed from spindle-shape into polygonal or short-column-shape. Some of these post-treated cells could contract spontaneously and rhythmically. The expression of GATA-4 and cTnT was increased 1 and 2 week(s) after the treatment. And about 16.6% of post-treated cells were cTnT-positive. Therefore, we are led to conclude that skeletal muscle-derived stem cells could differentiate into cardiocyte-like cells, which exhibited some characteristics of cardiocytes.
ABSTRACT
Pleiotrophin, discovered in 1989, was thought as a muhi-funetional growth factor; It plays an important role in tumor occurrence and central neural system. The latest research showed pleiotrophin signal pathway probably takes part in neural repair after peripheral nerve injury, especially in the followed crisis point, such as the protection of spinal cord neuron, the promotion of the speed of neuron axon regeneration, the guidance of neuron axon regeneration, skeleton muscle reirmervation. It potentially makes a key role in the guidance of neural axon regeneration in peripheral neural system and muscle reianervation. Along with the related researches go deep, pleiotrophin gene might become a controllable target for promoting the result of peripheral neural repair and reconstructing the neuromuscular junction.