BACKGROUND:The imbalance between bone resorption and bone formation in microgravity environments leads to significant bone loss in astronauts.Current research indicates that bone loss under microgravity conditions is the result of the combined effects of various cells,tissues,and systems. OBJECTIVE:To review different biological effects of microgravity on various cells,tissues,or systems,and summarize the mechanisms by which microgravity leads to the development of osteoporosis. METHODS:Databases such as PubMed,Web of Science,and the Cochrane Database were searched for relevant literature from 2000 to 2023.The inclusion criteria were all articles related to tissue engineering studies and basic research on osteoporosis caused by microgravity.Ultimately,85 articles were included for review. RESULTS AND CONCLUSION:(1)In microgravity environment,bone marrow mesenchymal stem cells tend to differentiate more into adipocytes rather than osteoblasts,and hematopoietic stem cells in this environment are more inclined to differentiate into osteoclasts,reducing differentiation into the erythroid lineage.At the same time,microgravity inhibits the proliferation and differentiation of osteoblasts,promotes apoptosis of osteoblasts,alters cell morphology,and reduces the mineralization capacity of osteoblasts.Microgravity significantly increases the number and activity of osteoclasts.Microgravity also hinders the differentiation of osteoblasts into osteocytes and promotes the apoptosis of osteocytes.(2)In a microgravity environment,the body experiences changes such as skeletal muscle atrophy,microvascular remodeling,bone microcirculation disorders,and endocrine disruption.These changes lead to mechanical unloading in the bone microenvironment,insufficient blood perfusion,and calcium cycle disorders,which significantly impact the development of osteoporosis.(3)At present,the mechanism by which microgravity causes osteoporosis is relatively complex.A deeper study of these physiological mechanisms is crucial to ensuring the health of astronauts during long-term space missions,and provides a theoretical basis for the prevention and treatment of osteoporosis.

OBJECTIVE To investigate the effects and potential mechanism of Qiangxin decoction on mitochondrion of rats with chronic heart failure （CHF）. METHODS The CHF model was established by ligating the left anterior descending branch of the coronary artery. Modeled rats were divided into model group， Qiangxin decoction low-dose and high-dose groups （12.25， 24.50 g/kg， calculated by crude drug）， and chemical medicine group （Sacubitril valsartan sodium tablets， 10.42 mg/kg）， with 10 rats in each group； control group was set up without treatment. Each group of rats was orally administered with the corresponding medication or normal saline twice a day for 28 consecutive days. After the last medication， the contents of N-terminal pro-brain natriuretic peptide （NT-proBNP） and adenosine triphosphate （ATP） in serum and phosphatidic acid （PA） and cardiolipin （CL） in myocardial tissue were all detected； the pathological damage and collagen fibrosis of rat myocardial tissue were observed； the apoptosis of myocardial cells was determined； the ultrastructure of myocardial tissue was observed； the protein expressions of mitofusin 1 （Mfn1）， Mfn2， optic atrophy protein 1 （OPA1） and dynamin-related protein 1 （Drp1） were all detected in myocardial tissue. RESULTS Compared with control group，the serum content of NT-proBNP， apoptotic rate of myocardial cells， and relative expressions of S-OPA1 and Drp1 proteins were all increased significantly； serum content of ATP，contents of PA and CL， and relative expressions of Mfn1， Mfn2 and L-OPA1 proteins were all significantly reduced （P＜0.05）. There were abnormal membrane tissue structure in various layers of myocardial tissue， degeneration and necrosis of myocardial cells， and severe fibrosis； the mitochondria were swollen， with reduced or absent cristae， and uneven matrix density. After intervention with Qiangxin decoction， the levels of the aforementioned quantitative indicators in serum and myocardial tissue of rats （excluding CL content in the Qiangxin decoction low- dose group） were significantly reversed （P＜0.05）； the pathological damage of myocardial tissue had significantly improved， fibrosis had significantly reduced， mitochondrial morphology tended to be normal， cristae had increased， and matrix density was uniform. CONCLUSIONS Qiangxin decoction can regulate myocardial mitochondrial function and structural integrity of CHF rats， thereby improving myocardial energy metabolism and antagonizing myocardial fibrosis， the mechanism of which may be associated with activating PA/Mfn/CL signaling pathway.

OBJECTIVE To investigate the effects and potential mechanism of Qiangxin decoction on mitochondrion of rats with chronic heart failure （CHF）. METHODS The CHF model was established by ligating the left anterior descending branch of the coronary artery. Modeled rats were divided into model group， Qiangxin decoction low-dose and high-dose groups （12.25， 24.50 g/kg， calculated by crude drug）， and chemical medicine group （Sacubitril valsartan sodium tablets， 10.42 mg/kg）， with 10 rats in each group； control group was set up without treatment. Each group of rats was orally administered with the corresponding medication or normal saline twice a day for 28 consecutive days. After the last medication， the contents of N-terminal pro-brain natriuretic peptide （NT-proBNP） and adenosine triphosphate （ATP） in serum and phosphatidic acid （PA） and cardiolipin （CL） in myocardial tissue were all detected； the pathological damage and collagen fibrosis of rat myocardial tissue were observed； the apoptosis of myocardial cells was determined； the ultrastructure of myocardial tissue was observed； the protein expressions of mitofusin 1 （Mfn1）， Mfn2， optic atrophy protein 1 （OPA1） and dynamin-related protein 1 （Drp1） were all detected in myocardial tissue. RESULTS Compared with control group，the serum content of NT-proBNP， apoptotic rate of myocardial cells， and relative expressions of S-OPA1 and Drp1 proteins were all increased significantly； serum content of ATP，contents of PA and CL， and relative expressions of Mfn1， Mfn2 and L-OPA1 proteins were all significantly reduced （P＜0.05）. There were abnormal membrane tissue structure in various layers of myocardial tissue， degeneration and necrosis of myocardial cells， and severe fibrosis； the mitochondria were swollen， with reduced or absent cristae， and uneven matrix density. After intervention with Qiangxin decoction， the levels of the aforementioned quantitative indicators in serum and myocardial tissue of rats （excluding CL content in the Qiangxin decoction low- dose group） were significantly reversed （P＜0.05）； the pathological damage of myocardial tissue had significantly improved， fibrosis had significantly reduced， mitochondrial morphology tended to be normal， cristae had increased， and matrix density was uniform. CONCLUSIONS Qiangxin decoction can regulate myocardial mitochondrial function and structural integrity of CHF rats， thereby improving myocardial energy metabolism and antagonizing myocardial fibrosis， the mechanism of which may be associated with activating PA/Mfn/CL signaling pathway.

Background/Aims: Obesity is associated with several gastrointestinal (GI) disorders and has been identified as a potential risk factor for various GI symptoms. Bowel frequency is an important indicator of bowel function. However, the causal link between obesity and gastrointestinal motility remains uncertain. This study aims to determine the causal effect of overall and central obesity on stool frequency. Methods: Four obesity-related anthropometric indicators–body mass index, body fat percentage, waist circumference (WC), and waist-tohip ratio (WHR)–were investigated. Individual-level baseline information from the UK Biobank was used to explore observational associations between obesity and stool frequency. Additionally, summary-level data from published genome-wide association studies were subjected to two-sample Mendelian randomization (MR) analyses to examine causal associations. Results: For all 4 indicators of obesity, higher levels of obesity were associated with more frequent bowel movements after adjusting for demographic characteristics, lifestyle, and dietary factors. After rigorous screening, 482 body mass index single nucleotide polymorphisms (SNPs), 7 body fat percentage SNPs, 48 WC SNPs, and 287 WHR SNPs were identified as instrument variables for MR analysis. The MR results were generally consistent with observational findings, proving that the associations observed in the overall obesity indicators were causal. For central obesity, the association between WHR and stool frequency remained consistent in both analysis phases, whereas WC showed a multidirectional association. Conclusions Obesity-related anthropometric indicators were causally associated with increased stool frequency in the overall and central obesity groups. Weight loss could be a potential approach to improve gastrointestinal regularity in individuals with obesity.

Background/Aims: Obesity is associated with several gastrointestinal (GI) disorders and has been identified as a potential risk factor for various GI symptoms. Bowel frequency is an important indicator of bowel function. However, the causal link between obesity and gastrointestinal motility remains uncertain. This study aims to determine the causal effect of overall and central obesity on stool frequency. Methods: Four obesity-related anthropometric indicators–body mass index, body fat percentage, waist circumference (WC), and waist-tohip ratio (WHR)–were investigated. Individual-level baseline information from the UK Biobank was used to explore observational associations between obesity and stool frequency. Additionally, summary-level data from published genome-wide association studies were subjected to two-sample Mendelian randomization (MR) analyses to examine causal associations. Results: For all 4 indicators of obesity, higher levels of obesity were associated with more frequent bowel movements after adjusting for demographic characteristics, lifestyle, and dietary factors. After rigorous screening, 482 body mass index single nucleotide polymorphisms (SNPs), 7 body fat percentage SNPs, 48 WC SNPs, and 287 WHR SNPs were identified as instrument variables for MR analysis. The MR results were generally consistent with observational findings, proving that the associations observed in the overall obesity indicators were causal. For central obesity, the association between WHR and stool frequency remained consistent in both analysis phases, whereas WC showed a multidirectional association. Conclusions Obesity-related anthropometric indicators were causally associated with increased stool frequency in the overall and central obesity groups. Weight loss could be a potential approach to improve gastrointestinal regularity in individuals with obesity.

Background/Aims: Obesity is associated with several gastrointestinal (GI) disorders and has been identified as a potential risk factor for various GI symptoms. Bowel frequency is an important indicator of bowel function. However, the causal link between obesity and gastrointestinal motility remains uncertain. This study aims to determine the causal effect of overall and central obesity on stool frequency. Methods: Four obesity-related anthropometric indicators–body mass index, body fat percentage, waist circumference (WC), and waist-tohip ratio (WHR)–were investigated. Individual-level baseline information from the UK Biobank was used to explore observational associations between obesity and stool frequency. Additionally, summary-level data from published genome-wide association studies were subjected to two-sample Mendelian randomization (MR) analyses to examine causal associations. Results: For all 4 indicators of obesity, higher levels of obesity were associated with more frequent bowel movements after adjusting for demographic characteristics, lifestyle, and dietary factors. After rigorous screening, 482 body mass index single nucleotide polymorphisms (SNPs), 7 body fat percentage SNPs, 48 WC SNPs, and 287 WHR SNPs were identified as instrument variables for MR analysis. The MR results were generally consistent with observational findings, proving that the associations observed in the overall obesity indicators were causal. For central obesity, the association between WHR and stool frequency remained consistent in both analysis phases, whereas WC showed a multidirectional association. Conclusions Obesity-related anthropometric indicators were causally associated with increased stool frequency in the overall and central obesity groups. Weight loss could be a potential approach to improve gastrointestinal regularity in individuals with obesity.

Acupuncture, a therapeutic treatment defined as the insertion of needles into the body at specific points (ie, acupoints), has growing in popularity world-wide to treat various diseases effectively, especially acute and chronic pain. In parallel, interest in the physiological mechanisms underlying acupuncture analgesia, particularly the neural mechanisms have been increasing. Over the past decades, our understanding of how the central nervous system and peripheral nervous system process signals induced by acupuncture has developed rapidly by using electrophysiological methods. However, with the development of neuroscience, electrophysiology is being challenged by calcium imaging in view field, neuron population and visualization in vivo. Owing to the outstanding spatial resolution, the novel imaging approaches provide opportunities to enrich our knowledge about the neurophysiological mechanisms of acupuncture analgesia at subcellular, cellular, and circuit levels in combination with new labeling, genetic and circuit tracing techniques. Therefore, this review will introduce the principle and the method of calcium imaging applied to acupuncture research. We will also review the current findings in pain research using calcium imaging from in vitro to in vivo experiments and discuss the potential methodological considerations in studying acupuncture analgesia.
Calcium ; Acupuncture Therapy ; Acupuncture ; Acupuncture Analgesia/methods* ; Acupuncture Points ; Technology

Objective To establish and validate a method for simultaneous determination of 9 sedative-hypnotics in human plasma,and to explore the preliminary clinical application.Methods Plasma samples were precipitated with acetonitrile and determined by high performance liquid chromatography tandem mass spectrometry.The column was Agilent Poroshell 120 EC-C18(2.1 mm × 50.0 mm,2.7μm)and eluted with acetonitrile water containing 0.1％formic acid in an equal degree program at a flow rate of 0.3 mL·min-1.The column temperature was 20 ℃ and injection volume was 5 μL.The deprotonated ions of analytes were ionized by positive ion,electron spray ionization and multiple reaction monitoring mode.The specificity,standard curve and lower limit of quantification,precision and recovery,matrix effect,stability and dilution effect of the method were investigated.Results Excellent linear relationship with correlation coefficient of r2 ≥ 0.997 7 was obtained.The linear of esazolam,alprazolam,oxazepam,clonazepam,lorazepam,triazolam,midazolam,diazepam and zolpidem were 18-1 800,4.5-450,25-2 500,3.5-350,25-2 500,1.5-150,5.5-550,35-3 500,4-400 ng·mL-1,respectively.The lower limit of quantification were 18,4.5,25,3.5,25,1.5,5.5,35,4 ng·mL-1.The method was accurate and precise with acceptable intra-day and inter-day precisions(relative standard deviations were less than 20％for a lower limit of quantification and less than 15％for other quality control samples)and an accuracy of 86.21％-112.38％.The extraction recovery rate were 93.07％-110.50％.The matrix factors normalized by internal standard were 86.61％-108.41％,relative standard deviations were less than 15％.Plasma samples remained stable under various storage conditions.The precision and accuracy of plasma samples were acceptable after dilution.Conclusion The method is simple,rapid,sensitive and specific,and it can be used for simultaneous detection of the 9 sedative-hypnotics in human plasma.

ObjectiveTo identify and clarify the key issues faced by tertiary hospitals in responding to public health emergencies. MethodsA literature review index system was constructed， and key issues were identified using hierarchical analysis. ResultsAfter a systematic literature review， 20 types of problems faced by tertiary hospitals in responding to public health emergencies were identified. Three key issues were ultimately identified by prioritizing the issues that needed to be addressed. ConclusionThe key issues of tertiary hospitals in responding to public health emergencies are concentrated in the areas of emergency response capabilities and competencies of medical staff， the number of emergency response personnel， and the standardization and specificity of training and drills. Tertiary hospitals should focus on these issues in developing public health emergency response systems to improve the effectiveness of their emergency response.

ObjectiveTo identify the key issues in emergency response to public health emergencies in the Yangtze River Delta region， and to provide a basis for the formulation of relevant policies. MethodLiterature on emergency response to public health emergencies in the Yangtze River Delta region was systematically reviewed and collected， and 18 main problems were identified after collecting and organizing the problems. A questionnaire survey and cluster analysis were used to identify the key issues. ResultsThe study of 18 major problems revealed that "insufficient reserve of emergency medical supplies"， "insufficient financial investment to meet the needs of emergency response"， "lack of a sound mechanism for the deployment of supplies， resulting in the untimely deployment of materials"， were the key issues of emergency response to public health emergencies in the Yangtze River Delta region. ConclusionFuture development of the emergency response system in the Yangtze River Delta region should focus on accelerating the integration process of the Yangtze River Delta， establishing and improving information systems， optimizing the material storage and deployment network， prioritizing the fund investment and utilization mechanism， and improving the effectiveness of public health emergency response.