BACKGROUND:Until now, it is stil unclear whether the stem cel transplantation triggersadverse effects on the myocardial electrical activity, resulting in the emergence of arrhythmia.
OBJECTIVE:To explore the effect of intracoronary transplantation of umbilical cord blood stem cels on arrhythmia score and incidence of ventricular arrhythmia.
METHODS:According to therapeutic strategies, 73patients with coronary heart disease were assigned to receive drug therapy in control group (n=38) and umbilical cord blood stem cel transplantation in observation group (n=35). Arrhythmia score, incidence of ventricular arrhythmia and adverse reactions were recorded and analyzed before and 1, 4, 8 weeks after transplantation.
RESULTS AND CONCLUSION:After treatment, arrhythmia scores were significantly reduced in the two groups, especialy in the observation group, to exhibit a continuous decline trend (P< 0.05). Compared with the control group, the incidence of ventricular arrhythmia was significantly lower in the observation (P< 0.05). However, there were no significant changes in the blood pressure, heart rate and blood oxygen saturation before and after transplantation, and no acute heart failure and death occurred in thetwo groups. These results suggest that the intracoronary transplantation of umbilical cord blood stem cels exhibits superiorities in the treatment of coronary artery disease, significantly reducing the arrhythmia score, reducing the incidence of ventricular arrhythmia, and resulting in less adverse reactions.

Objective:To research and design a negative pressure environment that can be applied in container type of biological isolation shelter,so as to meet the stable negative pressure environment and dynamic intelligent regulation of pressure difference in the container during multimodal transportation,especially under air freight conditions.Methods:The design specifications and research achievements of pressure differences of negative pressure isolation equipment for infectious diseases at home and abroad were comprehensively analyzed.And then,one kind of power-distributed ventilation system without air duct was designed to achieve.The preseted pressure redundancy,real-time monitoring of sensors and dynamic follow-up of pressure were used to realize stable and intelligent regulation of negative pressure within the container during air freight.Results:After testing,the pressure differences of each region of the"three regions and two channels"included clean region,buffer region,contamination region,medical staff passage and patient passage within container type of biological isolation shelter under the negative pressure environment could meet the preseted requirements.The values of pressure differences at the outside of room of clean region,the toilet of clean region,the toilet of clean region of the second dressing room of the buffer region,the contamination region of the first dressing room of the buffer region,the toilet of contamination region and the outside of the room of contamination region were respectively 34.2,38.8,-8.0,-31.7,-15.1 and-44.6.The conditions of the pressure differences within each region of container,which dynamically met the requirements of Biosafety Level-Ⅲ(BSL-3)laboratory,were tested through the sensors,and intelligent display and control equipment that deployed inside of container.Conclusion:The stable negative pressure environment and intelligent regulation for pressure difference in each region of the container can take container to have more high biosafety characteristics,which can effectively ensure the safe transportation of whole region for patients with severe infectious diseases,and the transport and treatment under air freight condition.