Objective To study the changes and mechanism of skin stem cells in microgravity.Methods The skin stem cells of SD rats were used to establish a suspension culture system and compare the proliferation of skin stem cells with 1G gravity.Results The simulated microgravity significantly affected the velocity of skin stem cell sphere proliferation in suspension culture,which was about 12%higher than the 1G gravity group.Transcriptome sequencing showed that 1673 genes were up-regulated and 1409 genes were downregulated;Calcium signaling;cytokine-cytokine receptor interaction and PPAR pathway were different in the two environments.Conclusion Simulation of microgravity can affect the proliferation behavior of skin stem cells in suspension culture by regulating the expression of key signaling pathways,which provides an experimental basis for further research in spatial microgravity environ ment.

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.

Objective To investigate the relationship between cellular immune response which is related with Th1/Th2 cells and the different severities of tuberculosis pleural effusion adhesion.Methods A total of 66 in-patients diagnosed with different severities of tuberculosis pleural effusion adhesion by internal thoracoscope were enrolled from August 2014 to December 2016.ELISA was used to determine levels of INF-γ,TNF-α,IL-2 and IL-4. The ratio of Th1 and Th2 cells was detected by flow cytometry. Results All the patients were divided into 3 groups:9 cases without pleural adhesion,32 cases with mild pleural adhesion,25 cases with severe pleural adhe-sion. The levels of 4 cytokines in pleural fluid were significantly higher than those in serum in each group(P <0.05,respectively).The concentrations of INF-γ and TNF-α were increased with the severity of tuberculosis pleu-ral effusion adhesion. The levels of INF-γ and TNF-α in the severe pleural adhesion group were markedly higher than those in the other two groups(P<0.05,respectively).The proportion of Th1 cells in the severe pleural adhe-sion group was significantly higher than that in the none pleural adhesion group and in the mild pleural adhesion group(P<0.05,respectively).Conclusions The proportion of Th1 cells and levels of INF-γ and TNF-α are pos-itively related with pleural adhesion severity. Cellular immune response which is related with Th1 cells contributes to pathological immune pleural damage and intensify the severity of pleural adhesions.

Objective To investigate the clinical efficacy of montelukast sodium and procaterol for treating the children with chronic cough and its impact on serum immunoglobulin E(IgE).Methods Eighty cases of children with chronic cough were divided into treatment group and control group by random digits table method with 40 cases each.The control group was given procaterol treatment on the basis of conventional treatment,and the treatment group was added montelukast sodium on the basis of treatment of control group.Treatment course was 1 month.Before and after treatment,the clinical symptoms and signs in the two groups were observed,the serum IgE level was detected,the clinical efficacy was evaluated,and the adverse reaction was observed.Results The total effective rate in the treatment group was 95.0％ (38/40),the control group was 67.5％ (27/40),and the difference was significant (x2 =9.928,P ＜ 0.01).The time of cough mitigation and disappearance in the treatment group was (24.41 ± 8.14) d and (41.27 ± 14.74) d,which was lower than that in the control group [(47.27 ± 15.76) d and (57.78 ±20.64) d],and the difference was significant (t =8.153,4.118,P ＜ 0.05).After treatment,the serum IgE level in the treatment group and control group significantly decreased [(295.27 ± 105.45)μg/L vs.(594.48 ± 198.16)μg/L,(427.78 ± 152.78) μ g/L vs.(567.21 ± 189.07) μ g/L,t =8.430,3.628,P ＜ 0.05],and the difference was significant between them (t =4.515,P ＜0.05).There were no serious adverse reactions in two groups.Conclusions The serum IgE may play an important role in the incidence of children with chronic cough,and montelukast sodium and procaterol for treating the children with chronic cough is safe,effective and worthy of clinical application.

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.

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.

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.

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 μmol/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.

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.

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.