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ObjectiveToinvestigatetheprotectiveeffectandmechanismofscutelarincombinedwith paeoniflorin after permanent cerebral ischemia in rats. Methods Forty-eight adult male SD rats w ere randomly divided into four groups: sham-operation, cerebral ischemia, scutelarin+ paeoniflorin, and cyclopamine (n=12 in each group). A model of permanent middle cerebral artery occlusion w as induced by suture method. The intraperitoneal injection of cyclopamine 6 mg/kg, a specific inhibitor of sonic hedgehog (SHH) pathw ay, at 15 min before ischemia in the cyclopamine group, w hile other groups w ere intraperitoneal y injected an equal volume of saline. At 0 hour and 3 hours after ischemia, the scutel arin+paeoniflorin group and cyclopamine group w ere intraperitoneal y injected scutel arin ( 20 mg/kg ) and paeoniflorin (30 mg/kg), while other groups were intraperitonealy injected an equal volume of saline. Neurological deficit scores w ere performed at 24 hours after ischemia, and then the rats w ere decapitated. The cerebral infarct volume w as measured by using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Real-time fluorescent quantitative polymerase chain reaction and Western blotting w ere used respectively to detect the expression levels of SHH, Patched-1, Gli-1 mRNAs and proteins in the ischemic cortex. Results The neurological deficit scores in the cerebral ischemia group, scutel arin+paeoniflorin group, and cyclopamine group w ere 3.33 ±0.52, 1.50 ±0.55, and 3.67 ±0.52, respectively. The neurological deficit score in the scutel arin+paeoniflorin group w as significantly low er than that in the cerebral ischemia group ( P<0.05), and the neurological deficit score in the cyclopamine group w as significantly higher than that in the scutelarin+paeoniflorin group ( P<0.05). The infarct volume percentage in the cerebral ischemia group, scutelarin+paeoniflorin group, and cyclopamine group were 31.77%±1.19%, 22.94%±2.65%, and 35.53%±0.20%, respectively. The infarct volume in the scutel arin+paeoniflorin group w as significantly less than that in the cerebral ischemia group ( P<0.05), and the infarct volume in the cyclopamine group was significantly larger than that of the scutelarin+paeoniflorin group (P<0.05). The expression levels of SHH, Patched-1, Gli-1 mRNAs and proteins in the cerebral ischemia group, scutelarin+paeoniflorin group, and cyclopamine group w ere significantly higher than those in the sham -operation group (al P<0.05). The expression levels of SHH, Patched-1, Gli-1 mRNAs and proteins in the scutelarin+paeoniflorin group were significantly higher than those in the in the cerebral ischemia group (al P<0.05), and the expression levels of Gli-1 mRNA and protein in the cyclopamine group were significantly lower than those in the scutelarin+paeoniflorin group ( al P<0.05 ). Conclusions The scutel arin combined w ith paeoniflorin has certain protective effect on focal cerebral ischemia injury in rats. Its mechanism is associated w ith the activation of SHH signaling pathw ay.
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Objective To investigate the effect of expressions of endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) in the ischemic cortex on ischemic cerebral injury in rats with diabetes mellitus.Methods A total of 36 healthy male Sprague-Dawley rats were divided into 3 groups:a shamoperation group,a cerebral ischemic group,and a diabetic cerebral ischemic group according to the random number table method.A diabetes model was induced by injection of streptozocin,and then,a permanent focal cerebral ischemic model was induced by the suture method.At 24 h after ischemia,the neurological deficit scores were conducted.The triphenyl tetrazolium chloride staining was used to measure the infarct volume.TUNEL was used to detect the apoptotic cells.Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression levels of VEGF and VEGFR2 mRNAs.Western blot was used to detect the expression levels of VEGF and VEGFR2 proteins.Results In the sham operation group,there were no neurological deficit and infarcts,and there were only a few apoptotic cells and a few expressions of VEGF,VEGFR2 mRNAs and protein.The neurological function score (4.25 ±0.54 vs.2.86 ±0.73);t =5.303,P＜0.001),infarct volume (51.69 ±2.26 mm3 vs.30.15 ±2.08 mm3;t =23.166,P＜0.001),and the number of apoptotic cells (24.22 ± 1.34/HP vs.13.28 ±0.37/HP;t =27.261,P＜0.001) in the diabetic cerebral ischernia group were significantly increased than those in the cerebral ischemic group,while VEGF,VEGFR2 mRNA,and protein expression level were significantly decerased (VEGF mRNA:4.74 ± 0.54 vs.6.71 ± 0.91,P ＜ 0.001;VEGFR2 mRNA:4.06 ± 0.60 vs.6.16 ± 0.96,P ＜ 0.001,VEGF protein:0.99 ± 0.13 vs.1.55 ± 0.23,P ＜ 0.001;VEGFR2 protein:4.12 ± 0.74 vs.6.23 ± 0.76,P ＜ 0.001) compare with the cerebral ischemic group.Conclusions VEGF/VEGFR2 signal pathway participates in diabetes aggravating ischemic cerebral injury.The downregulating of VEGF/VEGFR2 may be one of the mechanisms of diabetes aggravating ischemic cerebral injury.
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Glucagon and its analogues are a intestinal stimulating insulin screened by the small intestinal L cells. It can smoothly penetrate the blood-brain barrier into the brain tissue and play a neuropro-tective role. Liraglutide and glucagon and its analogues have higher homology. After entering the brain tissue, it is able to bind with the related receptors and activates Nrf2/HO-1 signaling pathway and thus reducing the production of oxidative stress products, increases the glutathione, heme oxygen synthase, superoxide dismutase and other phase Ⅱ detoxification enzymes, promotes angiogenesis, and protects the nerve cells of diabetes combined with cerebral ischemia injury.
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AIM:To evaluate the effect of microRNA-155(miRNA-155) on the regulation of angiogenesis in diabetic rats with cerebral ischemic injury .METHODS: Adult male Sprague-Dawley rats were randomly divided into 5 groups:sham group, cerebral ischemia group , diabetic cerebral ischemia group , diabetic cerebral ischemia +miRNA-155 inhibitors group and diabetic cerebral ischemia +scramble group .Diabetes model was made by injection of streptozocin and permanent cerebral ischemic model was developed by suture-occluded method .The scores of neurological deficit and infarct volume were estimated at 24 h after cerebral ischemia .miRNA-155 level was detected by real-time polymerase chain reaction.The expression of platelet endothelial cell adhesion molecule-1 ( PECAM-1/CD31 ) and vascular endothelial growth factor ( VEGF) was detected by Western blotting .RESULTS:miRNA-155 inhibitor significantly reduced miRNA-155 levels in the ischemic cortex (P<0.05), improved the scores of neurological deficit , reduced infarction size and up-regulated the levels of CD31 and VEGF (P<0.05).CONCLUSION:miRNA-155 has a critical role in the regulation of angiogenesis in diabetic rats with cerebral ischemia .Down-regulation of miRNA-155 using miRNA-155 inhibitor attenuates brain infarct injury in diabetic rats .
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After the functions and requirements of medical information officers and the distribution of enterprises were described, the problems in domestic education of medical informatics ( such as insufficient class hours for medical course and unclear orientation of subjects) were analyzed according to the status quo in training of medical informatics students, and some suggestions were put forward for the orientation of medical informatics education in China.