Objective To evaluate the effect of oxycodone postconditioning on myocardial ischemia-reperfusion (I/R) injury in rats.Methods Forty pathogen-free healthy adult male Sprague-Dawley rats,weighing 200-300 g,were randomly divided into 4 groups (n =10 each) using a random number table:sham operation group (group S),myocardial I/R group (group Ⅰ),oxycodone postconditioning group (group O),and selective protein kinase C inhibitor chelerythrine group (group CH).Myocardial ischemia was induced by 30 min occlusion of the left anterior descending branch of the coronary artery,followed by 120 min reperfusion.In group S,the left anterior descending branch of the coronary artery was only exposed but not ligated.In group CH,chelerythrine 5 mg/kg was injected intravenously and slowly via the jugular vein before ligation which was performed immediately after administration.In O and CH groups,oxycodone 0.5 mg/kg was injected intravenously and slowly via the jugular vein at 2 min before reperfusion.Arterial blood samples were taken at 120 min of reperfusion to detect the levels of cardiac troponin Ⅰ (cTnI) and creatine kinase-MB (CK-MB) in serum.The hearts were removed after the animals were sacrificed to measure the myocardial infarct size by TTC staining.Results Compared with group S,the levels of cTnI and CK-MB in serum and myocardial infarct size were significantly increased in Ⅰ,O and CH groups (P＜0.05).Compared with group Ⅰ,the levels of cTnI and CK-MB in serum and myocardial infarct size were significantly decreased in O and CH groups (P＜0.05).Compared with group O,the levels of cTnI and CK-MB in serum and myocardial infarct size were significantly increased in group CH (P＜0.05).Conclusion Oxycodone postconditioning can mitigate myocardial I/R injury in rats,and the mechanism is partially related to activation of protein kinase C signaling pathway.

Objective To investigate the effects of sinomenine on hind limb ischemia?reperfusion ( I∕R) injury and expression of Bcl?2 and Bax in skeletal muscle cells of rats. Methods Fifty?four healthy adult male Wistar rats, aged 6-8 weeks, weighing 180-220 g, were divided into 3 groups ( n=18 each) using a random number table: sham operation group ( group S) , group I∕R and sinomenine group ( group SIN) . The rats were subjected to 4 h of ischemia on the proximal part of the right hind limb using elastic rubber bands followed by reperfusion in I∕R and SIN groups. Sinomenine 60 mg∕kg was injected intraperito?neally at 30 min before reperfusion in group SIN, and the equal volume of normal saline was given instead of sinomenine at 30 min before reperfusion in S and I∕R groups. Immediately after onset of reperfusion and at 4 and 24 h of reperfusion, blood samples were collected from the cardiac apex to measure the concentra?tions of serum lactate dehydrogenase ( LDH) and creatine kinase ( CK) . The animals were sacrificed imme?diately after blood sampling, and the gastrocnemius specimens of the hind limb were immediately removed for determination of the wet to dry weight ratio ( W∕D ratio) and expression of Bcl?2 and Bax in gastrocnemi?us cells ( by immunohistochemistry) and for examination of the pathological changes after haematoxylin and eosin staining. The Bcl?2∕Bax ratio was calculated. Results Compared with group S, the gastrocnemius W∕D ratio and concentrations of serum LDH and CK were significantly increased, the expression of Bcl?2 was significantly down?regulated, the expression of Bax was significantly up?regulated, and the Bcl?2∕Bax
ratio was significantly decreased in I∕R and SIN groups ( P<0?05) . Compared with group I∕R, the gastroc?nemius W∕D ratio and concentrations of serum LDH and CK were significantly decreased, the expression of Bcl?2 was significantly up?regulated, the expression of Bax was significantly down?regulated, and the Bcl?2∕Bax ratio was significantly increased in group SIN ( P<0?05) . The pathological changes of the gastrocne?mius were significantly attenuated in group SIN as compared with group I∕R. Conclusion Sinomenine can attenuate hind limb I∕R injury, and the mechanism may be related to maintenance of the balance between Bcl?2 and Bax and to inhibition of apoptosis in skeletal muscle cells of rats.

Objective To study and analyze the risk factors in children with type 1 diabetes and formulate preventive health measures. Methods A total of 112 children with type 1 diabetes treated in our hospital from January 2017 to October 2019 were selected as the type 1 diabetes group, and 50 healthy children who underwent physical examination during the same period were selected as the control group. Multifactor logistic regression analysis was used to analyze predisposing factors of type 1 diabetes in children, and preventive health measures was proposed. Results The results of multivariate logistic regression analysis indicated that maternal age, passive smoking during pregnancy, milk feeding time, and children's respiratory infections were independent risk factors for children with type 1 diabetes (OR: 6404, 6.903, 6.417, 8.256, P <0.05). Conclusion Maternal age, passive smoking during pregnancy, milk addition time, and children's respiratory infections were independent risk factors for children with type 1 diabetes. Strengthening health education, breastfeeding as soon as possible, and preventing respiratory infections can help reduce the incidence of children with type 1 diabetes.