BACKGROUND:Autologous stem celltransplantation to the heart is a research direction of heart failure treatment, but there are relatively few of studies about autologous bone marrow mesenchymal stem celltransplantation targeting the cardiac conduction system. OBJECTIVE:To evaluate the potential of rabbit bone marrow mesenchymal stem cells for treatment of heart block. METHODS:Rabbit bone marrow mesenchymal stem cells were induced by 5-azacytidine to differentiate into cardiomyocyte-like cells. After thoracotomy, the left atrium-left ventricular anterior wal was sutured in 14 New Zealand white rabbits (8 in the experimental group and 6 in the control group). One month after the surgery, in the experimental group, autologous bone marrow mesenchymal stem cells induced by 5-azacytidine for 4 weeks were labeled with 4',6-diamidino-2-phenylindole and then injected into the suture area when opening the thoracic again. In the control group, cells cultured in medium were used. One month after celltransplantation, the third thoracotomy was done to insert electrodes into the left atrium and left ventricular anterior wal , for cardiac electrophysiological detection. Whether atrioventricular pathway formed in the suture area was observed. RESULTS AND CONCLUSION:After cells were transplanted into the sutured area, two rabbits in the experimental group were discovered to form the atrioventricular pathway in the sutured area through cardiac electrophysiological examination. After transplantation, transplanted cells were visible on the heart frozen sections under fluorescence microscope in the left ventricle and sutured area, but there was no cellin the control group. In the experimental group, bone marrow mesenchymal stem cells expressed Cx43 and formed gap junction intercellular communication with cardiomyocytes, which was presented as formation of the atrioventricular pathway on cardiac electrophysiology examination. These findings indicate that bone marrow mesenchymal stem cells can be used to treat cardiac conduction system block diseases.

American medical insurance is mainly composed of public medical insurance borne by the government and private medical insurance. The main cause of death in this country are ischemic heart disease, Alzheimer’s disease, and lung cancer. The motality rate mainly caused by drug use disorders, chronic kidney disease and Alzheimer’s disease. The development of Chinese herbal medicine is relatively slow and difficult. The education system has covered Traditional Chinese Medicine (TCM). However, there still exist certain challenges of the development of TCM acupuncture faces the challenge of localization; Chinese herbal medicine still lacks standardization and TCM education needs to be standardized. Based on the current situation, it is suggested to focus on the development of acupuncture and moxibustion, to promote the registration and declaration of Chinese herbal medicine products for treating difficult diseases, and to strengthen the international exchange of TCM education, so as to promote the development and spread of TCM in the United States.

OBJECTIVE To establish a comprehensive and rapid m ethod for the a nalysis of chemical constituents as phthalides and organic acids in Angelica sinensis ，and to provide scientific reference for the quality evaluation and pharmacodynamic substance research of A. sinensis . METHODS The 70％ ethanol extract of A. sinensis was analyzed by ultra high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry （UPLC-Q-TOF/MS）. The determination was performed on ACQUITY UPLC BEH-C 18 column with mobile phase consisted of 0.1％ formic acid solution- acetonitrile（gradient elution ）at the flow rate of 0.3 mL/min. The column temperature was set at 30 ℃，and sample size was 2 µL. The ion source was an electrospray ion source ，using positive ion scanning mode ，and the mass scanning range was m/z 50-1 000. Capillary voltage was 4 000 V； atomizer pressure was 35 psi；cracking voltage was 135 V and the taper hole voltage was 65 V；the temperature of dry gas was 320 ℃；the flow of dry gas was 10 L/min and the flow of sheath gas was 11 L/min；collision energy were 20 and 40 V. Qualitative Analysis 10.0 software was used to obtain the retention time of compounds ，the accurate mass number of excimer ion peaks and secondary fragments. The compounds were analyzed by comparing with the mass spectra of the reference substance ，combined with relevant literature ，mass spectrometry cleavage law and database such as Chemspider ，MassBank，PubChem. RESULTS A total of 72 compounds were identified or deduced from A. sinensis ，including 55 phthalides，13 organic acids and 4 other constituents. CONCLUSIONS The established method is rapid and accurate for the identification of chemical constituents from A. sinensis ，such as organic acids and phthalides ，which provides an efficient and rapid analytical method for the comprehensive characterization of its chemical constituents.