RESUMO
Objective:To fundamentally solve the problems of valve dysfunction caused by limited size of artificial valve, high requirements for implantation technology, destruction of subvalvular structure and proliferation of fibrous endothelial tissue. We have developed a prosthetic valve with zero left ventricular occupancy. The valve frame is appropriately higher than the existing products, slightly chimney shaped, fully accommodates the movement of the valve leaves in the valve frame, and completely supraannular surgical implantation. This study uses this valve for preclinical animal test.Methods:Seven sheep underwent the replacement of the artificial valve under the direct vision of cardiopulmonary bypass. Warfarin was used for anticoagulation for 6 months 24 hours after operation. The blood biochemistry, anticoagulation and cardiac color Doppler ultrasound were detected after operation. The sheep were killed 180 days later for autopsy to observe whether the artificial valve caused thromboembolism. The efficacy and safety of valve were observed.Results:Two of the seven sheep died within 24 hours after operation, and five survived for a long time. Later, they were killed at 180 days. The mechanical properties of the artificial valve were good, and there was no thromboembolism around the artificial valve and important organs. The tissue layer of suture ring has been completely organized and endothelial cells, and the thickness of tissue layer is about 0.6-1.0 mm. The mitral valve of experimental animals can be opened and closed freely, with smooth surface and no abnormal echo. The follow-up of color Doppler ultrasound showed that the left ventricular ejection fraction was normal (0.60-0.70) before and 6 months after operation. The results of cross valve pressure difference and blood flow velocity of artificial valve were good (vmean was far lower than 5 mmHg(1 mmHg=0.133 kPa) and pmean was lower than 1 m/s) , suggesting that the hemodynamic performance of artificial valve was good. Left ventricular retrograde angiography showed that the artificial valve was completely located in the left atrium with good position and normal opening and closing. There was no obvious perivalvular leakage and other abnormalities. Within 7 days of blood test, the indexes of surgical stress were more abnormal than those before operation. At 12 and 24 weeks, there were no obvious abnormalities in blood routine test, liver and kidney function and other blood test indexes of animals in each group.Conclusion:The new chimney shaped mechanical valve implanted completely above the mitral annulus has good wear resistance, histocompatibility, antithrombotic and hemodynamic performance.
RESUMO
Objective@#To study the effect of nutrition intervention on the body composition and blood glucose in newly diagnosed patients with type 2 diabetes mellitus complicated with overweight and obesity.@*Methods@#A total of 84 newly diagnosed patients with type 2 diabetes mellitus complicated with overweight and obesity were selected from the department of endocrinology in China-Japan Friendship Hospital from April 2015 to December 2016. Basic information and body composition of these patients were collected and measured. Also the food frequency questionnaire (FFQ) was used to investigate the dietary status in the past month, and calculate the intake of energy, three major nutrients and dietary fiber. All patients received nutrition intervention by nutritionist for three months as requested by Diabetes guidelines. After 3-month intervention, blood glucose, body composition and dietary status were examined again. Relevant indicators of patients were compared before and after the intervention. All patients were divided into three groups according to the degree of body mass index (BMI)′s change: <5%, 5%-10% and >10%. The differences of body weight, muscle, body fat rate, visceral fat index and blood glucose level among three groups were quantified.@*Results@#There were 53 male patients with age (41.5±8.9) years and HbA1c (7.5±0.4)%, and 31 female patients with age (40.1±8.5) years with HbA1c (7.6±0.5)%. The intake of energy, carbohydrate and fat of patients were significantly decreased (P<0.05) and dietary fiber was significantly increased (P<0.05) after nutrition intervention. The body weight, muscle mass, fat mass and visceral fat index were also significantly decreased (P<0.05). The average decrease of fat was about 2.8 kg accounting for 73.7% (2.8 kg/3.8 kg) of the total weight loss. The body fat rate decreased from (31.2±3.1)% to (28.8±3.2)% (P<0.05). The fasting blood glucose and postprandial blood glucose were both decreased significantly after intervention (P<0.05). Among three BMI decreased groups, there was no significant difference in body weight and muscle mass (P>0.05), but a significant difference in body fat rate and visceral fat index (P<0.05). The body fat rate, visceral fat index, fasting blood glucose and postprandial blood glucose had more decreases with the greater amount of weight loss (P<0.05).@*Conclusion@#The three-month nutrition intervention could change the dietary habit and components of patients with type 2 diabetes mellitus by reducing the blood glucose, body fat rate and visceral fat index significantly. The degree of reduced BMI is positively related to the decrease of fasting blood glucose and postprandial blood glucose.