Objective:To investigate the changes of gene or protein expression and activity of matrix metalloprotein9 (MMP9) and tissue inhibitor ofmetalloproteinasel (TIMP1) in the carotid artery (CA) of 4 wk hindlimb unweighted rat.Methods:A 4 weeks(wk) hindlimb unweighted (HU) rat model was used to simulate the effect of weightlessness on the cardiovascular system.Transmission electron microscopy was used to detect the content of ECM.Reverse transcriptase polymerase chain reaction(RT-PCR) was conducted to measure the mRNA content MMP and TIMP1.Immunohistochemistry and Western blot technique were used to measure the protein abundance.Gelatin zymography was carried out to detect the activity of MMP9.Results:Compared to the control group (CON),the area of ECM was enhanced (P＜0.05) and the content of collage fiber was increased (P＜0.05) in the CA of HU rats;moreover,HU did not affect the mRNA expression of MMP9,but significantly reduced the protein content (P＜0.05) or enzymatic activity (P＜0.05).Accordingly,the mRNA or protein expression of TIMP1 in the CA was significantly increased by HU (P＜0.05).Conclusion:Simulated weightlessness caused imbalance between MMP and TIMP1 expression,which might contribute to the ECM aggregation and stiffness of CA.

To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits, transthoracic RTMCE was performed in 10 healthy rabbits by using continuous infusion of SonoVue into the auricular vein. The short axis view at the papillary muscle level was obtained. The duration of the time that the contrast took to appear in right heart, left heart and myocardium was recorded. The regional myocardial signal intensity (SI) versus refilling time plots were fitted to an exponential function: y(t) =A(1-e(-beta(t-t0))) + C, where y is SI at any given time, A is the SI plateau that reflects myocardial blood volume, and beta is the slope of the refilling curve that reflects myocardial microbubble velocity. The A, beta and Axbeta values at different infusion rate of SonoVue were analyzed and the A, beta and Axbeta values in each segment in the short axis view at the papillary muscle level were compared. All the animal experiments were successful and high-quality images were obtained. The best intravenous infusion rate for SonoVue was 30 mL/h. The contrast appeared in right heart, left heart and myocardium at 7.5+/-2.2 s, 9.1+/-2.4 s and 12.2+/-1.6 s respectively. After 16.6+/-2.3s, myocardial opacification reached a steady state. The mean A, beta and Axbeta value in the short axis view at the papillary muscle level were 9.8+/-3.0 dB, 1.4+/-0.5 s(-1) and 13.5+/-3.6 dBxs(-1) respectively. A, beta and Axbeta values showed no significant differences among 6 segments. It was suggested that RTMCE was feasible for quantitative analysis of myocardial perfusion in rabbits. It provides a non-invasive method to evaluate the myocardial perfusion in rabbit disease models.

Objective To evaluate the effect and cost-benefit of catheter drainage combined with stoma bags in the management of fecal incontinence associated dermatitis. Methods Cochrane Library, PubMed, Embase, Web of Science, Chinese Biomedical Medical Disc, China National Knowledge Infrastructure, Wanfang database and VIP database were searched up to March 2016 for the relative randomized controlled trials of catheter drainage combined with stoma bags in the management of fecal incontinence associated dermatitis. Two researchers independently extracted data and evaluated the quality of literature. Then, meta-analysis was performed by using RevMan 5.3 software.Results A total of eight RCTs were involved and 788 patients were included in the research. Meta-analysis showed that compared with the traditional method, catheter drainage combined with stoma bags improved the effective rate of management in patients with fecal incontinence associated dermatitis (RR=1.40,95%CI(1.13,1.72),P=0.002); reduced the incidence rate of incontinence associated dermatitis [RR=0.16, 95%CI(0.09,0.31),P<0.000 01];and reduced nursing time [MD=-0.91, 95%CI(-1.31,-0.51),P<0.000 01].Conclusions Meta-analysis showed that, the effect of catheter drainage combined with stoma bags in the management of fecal incontinence associated dermatitis is better than the routine skin care method. However, the included studies is not enough, so a large sample of high-quality RCTs are needed for further verification.

Military flying labor hygiene is a discipline that focuses on influences of special flight environment and labor condition on human body and related prevent measures, with the core of flight fatigue. Health information and technique training can help flight surgeons to enhance professional competency and improve the prevention and recovery of military flying fatigue. The course construction of teaching system in this study included survey of demand, arrangement of content, identification of strategy, determination of evaluation, and feedback of results. Meanwhile, the textbook compilation, cultivation of teaching team and construction of laboratory were also needed. After a 4-year practice, a formal teaching system has been established and its teaching effectiveness has basically fulfilled the professional requirement for flight surgeons.

Objective:To study the chemical constituents in the roots of Tripterygium wilfordii. Methods: The compounds from Tripterygium wilfordii were isolated and purified by silica gel, Sephadex LH-20 and prep-HPLC chromatography, and their structures were elucidated based on the physiochemical properties and spectroscopic analysis. Results:Twelve compounds were isolated and iden-tified as wilforgine(1),wilforine(2),triptonoterpene methyl ether(3),glut-5-en-3β,28-diol(4),wilforol E(5),triptobenzene L (6),maytenoic acid(7),triptophenolide(8),celastrol(9),demethylzeylasteral(10),1-desacetyl wilforgine(11) and wilfortrine (12). Conclusion:The 1D and 2D NMR data of 1 and 2 are assigned for the first time,and the absolute configurations of 1 are con-firmed by X-ray single crystal diffraction.

Objective To localize Skin Condition Assessment Tool (SAT) in Chinese and test on the reliability and validity of scales.Methods Totally 50 incontinence associated dermatitis (IAD) patients who were admitted to Tianjin Medical University General Hospital between July and September 2016 were investigated and assessed in terms of their SAT reliability and validity.Results The validity of SAT re-test was 0.775;the correlation coefficient within the group was 0.977 (P＜0.01);the Cronbach′s α coefficient which stands for internal consistency was 0.836;the content validity index (CVI) was 0.93;there was one common factor in factor analysis;and the accumulated variance contribution rate was 78.561%.Conclusions The Chinese version of SAT has less entries and is easy to use. Its result has sound reliability and validity,hence applicable to the assessment of IAD severity.

Objective: To explore the association of tobacco/alcohol-excessive Internet usage and insufficient sleep with depressive symptoms among middle school students, so as to provide a reference for improving mental health of middle school students. Methods: In accordance with the cluster random sampling method, a total of 18 484 middle school students in Shanghai were surveyed from September to November 2022. Tobacco/alcohol-excessive Internet usage and sleep duration with depressive symptoms were assessed using the relevant scale items included in the questionnaire of Surveillance for Common Disease and Health Risk Factors among Students. The χ 2 test was used for inter group comparison, Logistic regression analysis and likelihood ratio test were used to analyze the independent and aggregated associations of tobacco/alcohol-excessive Internet use and insufficient sleep wiht depressive symptoms. Results: Self reported rates of tobacco/alcohol-excessive Internet usage, insufficient sleep and depressive symptoms among adolescents were 14.7%, 73.5% and 16.3%, respectively. Tobacco/alcohol-excessive Internet usage ( OR=2.69, 95%CI =2.44-2.97) and insufficient sleep ( OR=1.76, 95%CI =1.58-1.95) were associated with depressive symptoms ( P <0.05). Compared to middle school students with no tobacco/alcohol-excessive Internet usage and sufficient sleep, those with both tobacco/alcohol-excessive Internet usage and insufficient sleep showed the higher rate of depressive symptoms ( OR=4.71, 95%CI =4.08-5.44, P <0.05). Further stratified analysis results showed that, compared to the boys and the high school students, the separate and joint association of tobacco/alcohol-excessive Internet usage and insufficient sleep with depressive symptoms were more pronounced in the girls and the middle school students [ OR (95% CI ) for tobacco/alcohol-excessive Internet usage were 3.09 (2.68-3.56) and 4.74 (3.86-5.83), respectively; OR (95% CI ) for insufficient sleep were 1.86 (1.60-2.17) and 2.00 (1.58-2.53), respectively; and the OR (95% CI ) for the joint association were 6.05 (5.01-7.31) and 9.15 (6.98-11.99), respectively, P <0.05]. Conclusions Tobacco/alcohol-excessive Internet usage and insufficient sleep are associated with depressive symptoms in middle school students. Prevention and control strategies for adolescent mental health should be developed with consideration of health related behaviors, and also need to be tailored by focusing on gender and grade differences.

The liver is the most important digestive organ in the body. Several studies have explored liver biology and diseases related to the liver. However, most of these studies have only explored liver development, mechanism of liver regeneration and pathophysiology of liver diseases mainly based on two-dimensional (2D) cell lines and animal models.Traditional 2D cell lines do not represent the complex three-dimensional tissue architecture whereas animal models are limited by inter-species differences. These shortcomings limit understanding of liver biology and diseases. Liver organoid technology is effective in elucidating structural and physiological characteristics and basic tissue-level functions of liver tissue. In this review, formation strategies and a wide range of applications in biomedicine of liver organoid are summarized. Liver organoids are derived from single type cell culture, such as induced pluripotent stem cells (iPSCs), adult stem cells, primary hepatocytes, and primary cholangiocytes and multi-type cells co-culture, such as iPSC-derived hepatic endoderm cells co-cultured with mesenchymal stem cells and umbilical cord-derived endothelial cells. In vitro studies report that liver organoids are a promising model for regenerative medicine, organogenesis, liver regeneration, disease modelling, drug screening and personalized treatment. Liver organoids are a promising in vitro model for basic research and for development of clinical therapeutic interventions for hepatopathy.

The liver is the most important digestive organ in the body. Several studies have explored liver biology and diseases related to the liver. However, most of these studies have only explored liver development, mechanism of liver regeneration and pathophysiology of liver diseases mainly based on two-dimensional (2D) cell lines and animal models.Traditional 2D cell lines do not represent the complex three-dimensional tissue architecture whereas animal models are limited by inter-species differences. These shortcomings limit understanding of liver biology and diseases. Liver organoid technology is effective in elucidating structural and physiological characteristics and basic tissue-level functions of liver tissue. In this review, formation strategies and a wide range of applications in biomedicine of liver organoid are summarized. Liver organoids are derived from single type cell culture, such as induced pluripotent stem cells (iPSCs), adult stem cells, primary hepatocytes, and primary cholangiocytes and multi-type cells co-culture, such as iPSC-derived hepatic endoderm cells co-cultured with mesenchymal stem cells and umbilical cord-derived endothelial cells. In vitro studies report that liver organoids are a promising model for regenerative medicine, organogenesis, liver regeneration, disease modelling, drug screening and personalized treatment. Liver organoids are a promising in vitro model for basic research and for development of clinical therapeutic interventions for hepatopathy.

To evaluate the feasibility of real-time myocardial contrast echocardiography (RTMCE) by quantitative analysis of myocardial perfusion in rabbits,transthoracic RTMCE was performed in 10 healthy rabbits by using continuous infusion of Sono Vue into the auricular vein. The short axis view at the papillary muscle level was obtained. The duration of the time that the contrast took to appear in right heart,left heart and myocardium was recorded. The regional myocardial signal intensity (SI) versus refilling time plots were fitted to an exponential function:y(t) =A(1-e-β(t-t0)) + C,where y is SI at any given time,A is the SI plateau that reflects myocardial blood volume,and β is the slope of the refilling curve that reflects myocardial microbubble velocity. The A,β and A×β values at different infusion rate of SonoVue were analyzed and the A,β and A×β values in each segment in the short axis view at the papillary muscle level were compared. All the animal experiments were successful and high-quality images were obtained. The best intravenous infusion rate for Sono Vue was 30 mL/h. The contrast appeared in fight heart,left heart and myocardium at 7.5±2.2 s,9.1±2.4 s and 12.2±1.6 s respectively. After 16.6±2.3s,myocardial opacification reached a steady state. The mean A,β and A×β value in the short axis view at the papillary muscle level were 9.8±3.0 dB,1.4±0.5 s 1 and 13.5±3.6 dB×s-1 respectively.A,β and A×β values showed no significant differences among 6 segments. It was suggested that RTMCE was feasible for quantitative analysis of myocardial perfusion in rabbits. It provides a non-invasive method to evaluate the myocardial perfusion in rabbit disease models.