Research progress of tunneling nanotube in bone biology / 中华口腔医学杂志

Tunneling nanotube (TNT) is a newly discovered communication mode between animal cells in recent years, which have important physiological and pathological significance. However, the role of TNT in bone biology is still unclear. At present, there are many reports about tunneling nanotubes in bone marrow mesenchymal stem cells, osteoclast precursor cells, osteoblasts and immune cells. This review describes the research advances of TNT and its research progress in bone biology. It looks forward to the research direction of TNT in oral and maxillofacial bone development and bone biology, to provide new strategies for the maintenance of bone homeostasis and the treatment of bone diseases.

Effect and mechanism of Jiming Powder on myocardial fibrosis in mice with myocardial infarction / 中国中药杂志

Jiming Powder is a traditional ancient prescription with good therapeutic effect in the treatment of heart failure, but its mechanism lacks further exploration. In this study, a mouse model of coronary artery ligation was used to evaluate the effect and mechanism of Jiming Powder on myocardial fibrosis in mice with myocardial infarction. The study constructed a mouse model of heart failure after myocardial infarction using the method of left anterior descending coronary artery ligation. The efficacy of Jiming Powder was evaluated from multiple angles, including ultrasound imaging, hematoxylin-eosin(HE) staining, Masson staining, Sirius Red staining, and serum myocardial enzyme spectrum detection. Western blot analysis was performed to detect key proteins involved in ventricular remodeling, including transforming growth factor-β1(TGF-β1), α-smooth muscle actin(α-SMA), wingless-type MMTV integration site family member 3a(Wnt3a), β-catenin, matrix metallopeptidase 2(MMP2), matrix metallopeptidase 3(MMP3), TIMP metallopeptidase inhibitor 1(TIMP1), and TIMP metallopeptidase inhibitor 2(TIMP2). The results showed that compared with the model group, the high and low-dose Jiming Powder significantly reduced the left ventricular internal diameter in systole(LVID;s) and diastole(LVID;d), increased the left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS), effectively improved cardiac function in mice after myocardial infarction, and effectively reduced the levels of myocardial injury markers such as creatine kinase(CK), creatine kinase isoenzyme(CK-MB), and lactic dehydrogenase(LDH), thus protecting ischemic myocardium. HE staining showed that Jiming Powder could attenuate myocardial inflammatory cell infiltration after myocardial infarction. Masson and Sirius Red staining demonstrated that Jiming Powder effectively inhibited myocardial fibrosis, reduced the collagen Ⅰ/Ⅲ ratio in myocardial tissues, and improved collagen remodeling after myocardial infarction. Western blot results showed that Jiming Powder reduced the expression of TGF-β1, α-SMA, Wnt3a, and β-catenin, decreased the levels of MMP2, MMP3, and TIMP2, and increased the level of TIMP1, suggesting its role in inhibiting cardiac fibroblast transformation, reducing extracellular matrix metabolism in myocardial cells, and lowering collagen Ⅰ and α-SMA content, thus exerting an anti-myocardial fibrosis effect after myocardial infarction. This study revealed the role of Jiming Powder in improving ventricular remodeling and treating myocardial infarction, laying the foundation for further research on the pharmacological effect of Jiming Powder.

Mechanism of Jiming Powder in ameliorating heart failure with preserved ejection fraction based on metabolomics / 中国中药杂志

In this study, untargeted metabolomics was conducted using the liquid chromatography-tandem mass spectrometry(LC-MS/MS) technique to analyze the potential biomarkers in the plasma of mice with heart failure with preserved ejection fraction(HFpEF) induced by a high-fat diet(HFD) and nitric oxide synthase inhibitor(Nω-nitro-L-arginine methyl ester hydrochloride, L-NAME) and explore the pharmacological effects and mechanism of Jiming Powder in improving HFpEF. Male C57BL/6N mice aged eight weeks were randomly assigned to a control group, a model group, an empagliflozin(10 mg·kg~(-1)·d~(-1)) group, and high-and low-dose Jiming Powder(14.3 and 7.15 g·kg~(-1)·d~(-1)) groups. Mice in the control group were fed on a low-fat diet, and mice in the model group and groups with drug intervention were fed on a high-fat diet. All mice had free access to water, with water in the model group and Jiming Powder groups being supplemented with L-NAME(0.5 g·L~(-1)). Drugs were administered on the first day of modeling, and 15 weeks later, blood pressure and cardiac function of the mice in each group were measured. Heart tissues were collected for hematoxylin-eosin(HE) staining to observe pathological changes and Masson's staining to observe myocardial collagen deposition. Untargeted metabolomics analysis was performed on the plasma collected from mice in each group, and metabolic pathway analysis was conducted using MetaboAnalyst 5.0. The results showed that the blood pressure was significantly lower and the myocardial concentric hypertrophy and left ventricular diastolic dysfunction were significantly improved in both the high-dose and low-dose Jiming Powder groups as compared with those in the model group. HE and Masson staining showed that both high-dose and low-dose Jiming Powder significantly alleviated myocardial fibrosis. In the metabolomics experiment, 23 potential biomarkers were identified and eight strongly correlated metabolic pathways were enriched, including linoleic acid metabolism, histidine metabolism, alpha-linolenic acid metabolism, glycerophospholipid metabolism, purine metabolism, porphyrin and chlorophyll metabolism, arachidonic acid metabolism, and pyrimidine metabolism. The study confirmed the pharmacological effects of Jiming Powder in lowering blood pressure and ameliorating HFpEF and revealed the mechanism of Jiming Powder using the metabolomics technique, providing experimental evidence for the clinical application of Jiming Powder in treating HFpEF and a new perspective for advancing and developing TCM therapy for HFpEF.

A comparative study on safe sexual behavior and its intention among college students in Beijing between 2006 and 2016 / 中华疾病控制杂志

Objective To compare the changes of safe sexual behavior and its intention among college students in Beijing between 2006 and 2016, and to provide evidence for reproductive health education for prevention and control of sexually transmitted diseases (STDs). Methods By a stratified random sampling method,a questionnaire survey was conducted among college students in Beijing in 2006 and 2016 respectively. Results The rate of sexual behaviors declined ( 2=81.150,P<0.001), while the percentage of homosexual behavior among respondents in 2016 was higher than that in 2006( 2=12.115,P<0.001). Meanwhile, the age of first sexual intercourse (t=12.009, P<0.001) and the intention of safe sexual behavior declined( 2=10.375,P<0.001). In both surveys, the proportion of risk behaviors among students who ever had sexual behavior was higher than that of students never had sexual behavior. Multivariate linear regression analysis showed that the intention of safe sexual behavior among college students was associated with gender, age, self-efficacy of condom use, UNGASS index, visiting entertainment places and browsing pornographic information on the Internet(all P<0.05).Conclusions Compared with 2006, the safe sexualbehavior, intention and their risk factors among college students in Beijing changed greatly in 2016. The contents and approaches of intervention related to STDs and reproductive health should be changed according to the current situation in order to improve the intention of safe sexual behavior among college students and to control the occurrence of STDs.

HyaIuronic acid scaffoIds: appIication research and product prospects / 中国组织工程研究

BACKGROUND: Hyaluronic acid is an important component of extracellular matrix, has good biocompatibility, unique rheological properties and a variety of physiological functions. Therefore, it has wide application prospect in the tissue engineering. OBJECTIVE: To review the latest research progress in hyaluronic acid scaffold materials in different directions of tissue engineering. METHODS: Using the keywords of "hyaluronic acid, tissue engineering, regeneration, scaffold" in English and Chinese, we retrieved relevant articles published from January 2013 to September 2016 in the databases of PubMed, ScienceDirect and CNKI. RESULTS AND CONCLUSION: The application of hyaluronic acid tissue engineering scaffold materials mainly focuses on the regeneration of bone, cartilage, cardiovascular and nerve. The researchers optimize the composition, ratio of different materials, and modification or cross-linking methods to obtain the ideal scaffold materials to match the mechanical properties and physiological activity of the target tissue. However, there are not enough data on the influence of the molecular weight of hyaluronic acid and the original source of other raw materials on the scaffold properties. Further investigations are needed on the clinical transformation of hyaluronic acid tissue engineering products.