Objective To analyze the effect of transport and storage conditions on the detection of pathogenic nucleic acid MHV, Reo-3, MNV in laboratory mouse cecal contents samples. Methods MHV, Reo-3 and MNV were mixed with mouse cecal contents and used as reference samples,respectively. They were placed in the lysis buffer of RNA extraction reagent(buffer AVL)or normal saline, and stored at 4℃ and room temperature(22℃-25℃). RNA of these samples was extracted at 1,2,3,7,and 14 days. Then the amount of nucleic acid in samples was detected by real-time fluorescence quantitative PCR. Results A greater decrease of the amount of nucleic acid was observed when the samples were placed in normal saline than that kept in buffer AVL. The amount of nucleic acid in samples stored at 4℃ was found to be higher than that stored at 25℃ room temperature. The amount of nucleic acid in the samples which were kept in buffer AVL at 4℃ for 3 days was higher than 50%,still detectable in the samples kept for 7 days,and undetectable at 14 days. Conclusions Mouse cecal content samples are preferably stored in the lysis buffer of RNA extraction reagent and transported at 4℃ for the detection of MHV, Reo-3, and MNV nucleic acid. It is better to complete the detection test within 3 days.

Objective: To explore the effect of the umbilical cord mesenchymal stem cells(UC-MSCs) on the pulmonary fibrosis in silicosis rats. Methods: SPF male Sprague Dawley rats were randomly divided into control group, silica model group and UC-MSCs treatment group with 12 rats each group. SiO₂ intra-tracheal injection(0.5 ml of 50 mg/ml/rat) were applied to silica model group and UC-MSCs treatment groups. After that UC-MSCs treatment group received 1 ml UC-MSCs suspension (3×10⁶ cells/ml) by tail vein injection on the 29th, 36th, 43th and 50th day after exposure to the first silica suspension. On the 60th and 75th day after exposure to silica suspension, all animals were examed for pulmonary CT. Then the rats were euthanized on 75th day after the first exposure to silica.Lung's histopathological examination of the rats from all the groups were carried out. The content of hydroxyproline in lungs, TGF-β1 and IL-6 in serum were examined. Results: The lung's histopathological examination showed no obvious inflammatory cell and no fibrosis in the lung tissue of the control group, there were a lot of inflammatory cell aggregation and collagen fiber deposition in silica model group, while in the UC-MSCs intervention group and treatment group, there were less inflammatory cells and collagen fiber. The rats from silica model groups had higher HYP, TGF-β1 and IL-6 than the rats from UC-MSCs treatment group and control group. Lung fields of rats in the control group were clear and no obvious high-density shadow. Different-sized granular high-density shadows or reticular fibrous shadows were found diffusely distributed in the lungs of the rats in silica model group. Lung field of rats in UC-MSCs intervention group and treatment group were less high density shadows, and more clear. Conclusion UC-MSCs can alleviate the pulmonary fibrosis in silica model rats through regulating the secretion of some fibrosis related cytokines.

Objective:To summarize the best evidence of physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD).Methods:According to the 6S evidence model, BMJ Best Practice, UpToDate, Joanna Briggs Institute (JBI) database, National Guideline Clearinghouse (NGC), National Institute for Health and Clinical Excellence (NICE) network, Scottish Intercollegiate Guidelines Network (SIGN), Guidelines International Network (GIN), New Zealand Guideline Group (NZGG) network, Registered Nurses′ Association of Ontario (RNAO) network, Medlive, PubMed, Web of Science, Cochrane Library, CNKI, Wanfang Knowledge Data Service Platform, VIP database and Chinese Biomedical Database and European Respiratory Society/American Thoracic Society were searched systematically to obtain guidelines, expert consensus, best practice information book, clinical decision-making, recommended practice, and systematic review on PA management in patients with COPD. The data retrieval time was from the establishment of the databases to April 30, 2022. Two researchers with evidence-based medicine background evaluated the quality and extracted evidence of the included literature.Results:A total of 19 articles were selected including 4 guidelines, 2 clinical decision, 9 systematic reviews, 3 expert consensus and 1 randomized controlled trial. Finally, 33 pieces of best evidence were formed from 10 themes, namely pre-exercise assessment, exercise prescription, exercise style, time, intensity, PA location, safety and effectiveness of PA, intervention strategies, effect evaluation and quality control.Conclusions:This study summarizes the best evidence of PA in patients with COPD. Health professionals should choose and apply the best evidence with consideration of the clinical situation and patient preference.

Patients with chronic obstructive pulmonary disease have the disease phenomenon of fear of exercise because of dyspnea, which can accelerate the body degradation rate, weaken muscle strength, reverse increase dyspnea, and delay the recovery of the disease. As a result, this article examines the theoretical underpinnings and specific measures of dyspnea belief intervention programs for chronic obstructive pulmonary disease patients at home and abroad, summarizes the limitations of previous studies, and makes pertinent recommendations in an effort to serve as a guide for early patient prevention and the development of scientific and feasible intervention programs.