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BACKGROUND: Protein degradation is the main reason of exercise induced muscle damage (ElMO). High-intensity exercise may lead to the misfolding of proteins and fonn aggregates, which is harmful to the ultrastructure of skeleton muscle. OBJECTIVE: To determine the formation and role of protein aggregate (especially the desmin aggregate) in ElMO. METHODS: Sixty-four adult male Sprague-Dawtey rats (purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd., China) were randomly divided into eight groups (control, post-exercise 0, 3, 6, 12, 24, 48, and 72 hours, eight rats in each). A damage model was established by downhill running (-160, 16m/min, 90 minutes). All rats were then killed at corresponding time points to take the soleus as specimen. Severity of damage was observed histologically under a transmission electron microscope. Expression of ubiquitin in the insoluble protein of soleus muscle was detected using western blot, and expression of desmin aggregates was observed by immunofluorescence double labeling. All experimental procedures were approved by the Beijing Sport University Institutional Review Board. RESULTS AND CONCLUSION: (1) After a large-load eccentric exercise, the sarcomere of the soleus muscle was widened, the Z-line was broken, and the myofibril was broken and distorted, all of which was most serious at 12 hours after exercise, and recovered completely at 72 hours after exercise. (2) Western blot results indicated that the expression of ubiquitin in the skeletal muscle increased first and then decreased after a large-load eccentric exercise. The expression peaked at 12 hours after exercise and returned to normal at 72 hours after exercise. (3)0verall expression of desmin aggregates significantly raised (P < 0.01) instantly when the ElMO occurred. It reached the peak at 12 hours after exercise, then reduced somewhat (P < 0.01) at 24 and 48 hours, and finally recovered at 72 hours. (4)These findings indicate that desmin aggregation may be one of the causes of ElMO. [ABSTRACT FROM AUTHOR]

BACKGROUND: A high-intensity eccentric exercise may lead to skeletal muscle damage, endoplasmic reticulum stress, increasing misfolded proteins. Aggraphagy works as an effective way of controlling quality of proteins and plays an important role in damage repair. OBJECTIVE: To discover the activation degree of aggrephagy in the damage repair process after an overload eccentric exercise, and to discuss the role of aggrephagy in the exercise-induced muscle damage, which is supplementary to the protein degradation pathway in skeletal muscle damage. METHODS: Sixty-four male adult Sprague Dawley rats were randomly divided into a static control group (n=8) and seven exercise groups according to post-exercise time (0, 3, 6, 12, 24,48 and 72 hours, eight rats in each). Damage models were established by downhill running (-16°, 16m/min, 90 minutes). Subsequently, the histological changes of the rat soleus muscle was observed under an electron microscope and protein expressions of histone deacetylase 6 and microtubule-associated protein 1 light chain 3II/I related to aggrephagy were detected using western bot assay. RESULTS AND CONCLUSION: (1) Under the transmission electron microscope, the rat soleus muscle was disordered and widened and appeared to have transient sarcomere, the Z line was water wave-like, broken and disappeared, and the mitochondria were swollen and unevenly distributed with an unclear structure after high-intensity eccentric exercise. The model rats suffered severest muscle damage at 12 hours and recovered completely at 72 hours after high-intensity eccentric exercise. (2) After one-time eccentric exercise, the expression of histone deacetylase 6 had a transient increase. The histone deacetylase 6 expression reached the peak at 6 hours, then gradually reduced and recovered at 72 hours after exercise. The microtubule-associated protein 1 light chain 3II/I expression was significantly increased at 3 hours after exercise, reached the peak at 12 hours, then reduced significantly and recovered at 72 hours after exercise. All these findings indicate that aggrephagy transiently happens and exerts important roles in the clearance of misfolded proteins, maintenance of cellular environmental homeostasis and recovery of skeletal muscle damage. [ABSTRACT FROM AUTHOR]

This study attempts to develop a reference substance for the live bacteria count of Streptococcicosis live vaccines in order to evaluate the validity of live bacterial count in inspection and testing. We prepared a batch of live Streptococcus suis reference substance for live bacterial count, tested their physical property, purity, vacuum degree, remaining moisture, and determined their homogeneity, thermal stability and transportation stability. Moreover, we organized collaborative calibration to assign count values to the reference substance and determine the shelf life of the reference substance in 12 months. The results showed that the physical property, the purity, the remaining moisture and the vacuum degree of the reference substance were all in compliance with the requirements of the Chinese Veterinary Pharmacopoeia. The homogeneity test showed that the coefficient of variation of the count of the reference substance was less than 10%, indicating a good homogeneity. Transportation stability test showed that the reference substance remained active after 72 h transportation in summer and winter with the package of styrofoam boxes and ice packs. Thermal stability test showed that the reference substance could be stored for up to 3 months at -20 °C, or up to 21 days at 4 °C. According to the collaborative calibration, the reference vaccine was assigned a count value range of (8.5-12.1)×107 CFU/ampoule. The shelf life test showed that the reference substance was stable for 12 months when stored at -70 °C. The reference substance could provide a reference for the live bacterial count of Streptococcicosis live vaccines. Moreover, it could also be used as a reference to evaluate the quality of corresponding agar media.

Objective: To investigate the status of subjective well-being (SWB) for medical staffs who contact with patients directly in a tertiary hospital.
, Methods: Staffs from a tertiary hospital in Hunan province were investigated the SWB Scale (SWBS-cc20) from 2012 to 2014.
, Results: The scores of SWB for medical staffs are high (81.67±12.33). Among the 10 sub-dimensions of SWB, medical staffs performed the best in family atmosphere, personal growth, and interpersonal adaptation, while performed the worst in physical health, mental health and material contentment. Title, job nature, education and occupation significantly affected the status of SWB. Staffs who directly connected with patients have less scores of SWB than those who do not (t=-4.80, P<0.001). Moreover, they perform better in contentment (OR=0.079, 95% CI 1.278 to 2.214, P<0.001), but worse in mental health (OR=1.315, 95% CI 1.023 to 1.690, P<0.05) and physical health (OR=1.313, 95% CI 1.029 to 1.677, P<0.05).
, Conclusion: Medical staffs have high scores of SWB. Staffs who directly connected with patients have less scores of SWB than those who do not. Moreover, they perform better in contentment, but worse in mental health and physical health.

Objective: To investigate the effect of emodin on proliferation and cell cycle distribution of human oral squamous carcinoma cells in vitro., Methods: Cultured human oral squamous carcinoma Tca8113 cells were treated with 2.5, 5, 10, 20, 40, 60 and 80 µmol/L emodin for 24, 48 or 72 h, with the cells treated with 0.1% DMSO as control. MTT assay and flow cytometry were used to evaluate the changes in cell proliferation and cell cycle distribution, respectively. Western blotting was employed to analyze the changes in the expression levels of the cell cycle-related proteins CDK2, cyclin E and P21 after emodin treatment., Results: Emodin significantly inhibited the growth and proliferation of Tca8113 cells within 72 h in a time- and dose-dependent manner, and caused cell cycle arrest in G0-G1 phase. Western blotting revealed that emodin treatment significantly lowered the expression levels of CDK2, cyclin E and P21 proteins in Tca8113 cells (P<0.05)., Conclusion: Emodin can inhibit the proliferation of Tca8113 cells and affect their cell cycle distribution possibly by inhibiting the signaling pathways of cell cycle regulation.