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Objective:To study the effects of trioxygen pretreatment on cerebral ischemia/reperfusion (I/R) injury in rats.Methods:A total of 24 clean grade male Sprague-Dawley (SD) rats were randomly divided into Sham group, brain I/R group (I/R group) and Ozone pretreatment group (Ozone group), with 8 rats in each group. The animals were routinely fed, and the operation was performed 5 days after the intervention of Ozone group by intraperitoneal injection of trioxygen water (concentration 80 mg/L, 0.01 mL/g), and the Sham group and I/R group were injected with equal volume normal saline. The Sham group only separated the arteries without ligation, and the I/R group and Ozone group established the rat cerebral I/R model. Neurological deficit score (NDS) was performed 2 hours after ischemia and modified neurological deficit score (mNSS) was performed 24 hours after reperfusion. Brain tissue was collected after anesthesia. Cerebral infarction was observed by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and the percentage of cerebral infarction volume was calculated. Protein expression of metabolic glutamate receptor 5 (mGluR5) and ionic glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) subunit GluA2 in cerebral ischemic penumbra was determined by Western blotting.Results:Compared with the Sham group, NDS score, mNSS score and percentage of cerebral infarction volume in I/R group were increased [NDS score: 2.63±0.52 vs. 0, mNSS score: 9.63±1.19 vs. 1.13±0.64, cerebral infarction volume: (41.25±2.93)% vs. 0%, all P < 0.05], and expressions of mGluR5 and GluA2 in penumbra area of cerebral ischemia were decreased [mGluR5 protein (mGluR5/β-actin): 0.44±0.14 vs. 1.00±0.10, GluA2 protein (GluA2/β-actin): 0.23±0.08 vs. 1.00±0.25, both P < 0.05]. Compared with the I/R group, mNSS score and percentage of cerebral infarction volume in the Ozone group were decreased [mNSS score: 7.00±1.20 vs. 9.63±1.19, cerebral infarction volume: (27.23±6.21)% vs. (41.25±2.93)%, both P < 0.05], and mGluR5 and GluA2 expressions in the penumbra of cerebral ischemia were up-regulated [mGluR5 protein (mGluR5/β-actin): 0.81±0.10 vs. 0.44±0.14, GluA2 protein (GluA2/β-actin): 0.76±0.13 vs. 0.23±0.08, both P < 0.05]. Conclusion:Trioxygen preconditioning can alleviate cerebral I/R injury in rats, and its mechanism may be related to the upregulation of GluR5 and GluA2 in the ischemic penumbra.
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Objective To evaluate the effect of clemastine fumarate on Toll-like receptor 4/phosphatidylinositol-3-kinase/serine-threonine kinase (TLR4/PI3K/Akt) signaling pathway during hypoxia-reoxygenation (H/R) in rat cardiomyocytes.Methods H9C2 cells of rats cultured in vitro were seeded in culture wells or dishes at a density of 1×105 cells/ml and divided into 3 groups (n=11 each) by using a random number table method:control group (group C),H/R group and clemastine fumarate group (CF group).Cardiomyocytes were exposed to 5％ CO2-95％ N2in a low-glucose DMEM medium at 37℃ for 4 h followed by 4 h reoxygenation.At 4 h of reoxygenation,the cell viability was detected by CCK-8 assay,the ultrastructure was observed with a transmission electron microscope,the expression of TLR4,PI3K,phosphorylated Akt (p-Akt) and caspase-3 was detected by Western blot,and the expression of TLR4,PI3K and caspase-3 was detected by immunofluorescence.Results Compared with group C,the cell viability was significantly decreased,the expression of TLR4 and caspase-3 was up-regulated,and the expression of PI3K and p-Akt was down-regulated in group H/R (P＜0.05).Compared with group H/R,the cell viability was significantly increased,the expression of TLR4 and caspase-3 was down-regulated,the expression of PI3K and p-Akt was up-regulated (P＜0.05),and the mitochondrial damage was significantly attenuated in group CF.Conclusion The mechanism by which clemastine fumarate alleviates H/R injury to rat cardiomyocytes may be related to inhibiting TLR4 expression and activating PI3K/Akt signaling pathway.
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Objective To evaluate the effect of sevoflurane preconditioning on the expression of metabotropic glutamate receptor type Ⅱ( mGluRⅡ) during focal cerebral ischemia-reperfusion ( I∕R) in rats. Methods Forty-eight clean-grade healthy male Sprague-Dawley rats were divided into 3 groups (n＝16 each) using a random number table method: sham operation group ( group S), cerebral I∕R group (group I∕R) and sevoflurane preconditioning group (group Sev). Rats were anesthetized with 10% chloral hydrate 3 ml∕kg. Focal cerebral I∕R was produced by occlusion of the right middle cerebral artery for 2 h fol-lowed by 24 h reperfusion. In group Sev, 2. 7% sevoflurane was inhaled for 1 h and 24 h later focal cerebral I∕R was produced. At 24 h after reperfusion, neurological deficit was scored, the cerebral infarct size was determined by TTC staining, the cell apoptosis in ischemic penumbra was observed by TUNEL, IκB-α ex-pression was detected by Western blot, and mGluRⅡexpression was determined by immunofluorescent stai-ning. The apoptosis rate was calculated. Results Compared with group S, the neurological deficit score, cerebral infarct size and apoptosis rate were significantly increased, the expression of mGluRⅡwas up-regu-lated, and the expression of IκB-α was down-regulated in I∕R and Sev groups ( P＜0. 05). Compared with group I∕R, the neurological deficit score, cerebral infarct size and apoptosis rate were significantly de-creased, the expression of mGluRⅡwas down-regulated, and the expression of IκB-α was up-regulated in group Sev (P＜0. 05). Conclusion Sevoflurane preconditioning reduces focal cerebral I∕R injury through inhibiting the expression of mGluRⅡ in rats.
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Objective To detect the protein expression changes of mitochondrial apoptotic pathway during the reverse effects of lipid emulsion on bupivacaine cardiotoxicity, so as to investigate the probable mechanism concerning the reverse effect of lipid emulsion on bupivacaine cardiotoxicity.Methods The ventricular muscles of 15 healthy SD neonatal mice (1-3 d) were chosen to conduct primary culture in vitro.And the cardiomyocytes were cultivated in a medium containing bupivacaine for 24 hours to establish its bupivacaine poisoning model.The cultured cardiomyocytes were divided into three groups: control group (group C);bupivacaine group (group B);and bupivacaine+lipid emulsion group (group BL).Flow cytometry was applied to examine the apoptosis of cardiomyocytes, and the Western blot was employed to detect the protein expression variation of cytochrome C (Cyto-C) and cleaved casepase-3.Results Compared with group C, the apoptosis rate was remarkably increased in both group B and group BL and that of the group B was dramatically higher than that of the group BL, with a statistical significance (P<0.05).Compared with group C, the protein expression levels of both Cyto-C and cleaved casepase-3 were significantly increased in groups B and BL (P<0.05), and the protein expression levels of both Cyto-C and cleaved casepase-3 in group B were significantly higher than those in group BL (P<0.05).Conclusion Lipid emulsion can regulate apoptosis through inhibiting the release of mitochondrial Cyto-C and reducing casepase-3 activation, thus it protects cardiomyocytes.
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Under the condition of information society, we should cultivate students'!ability of infor-mation literacy and innovation. Based on the early investigation of medical students'!information ability and scientific research quality, we carried on a staged and systematic subject-oriented information literacy training for post-graduate students in specialty of anesthesiology through such measures as enriching infor-mation resources, strengthening students'!awareness of information, the implementation of the supervisor group system or double tutor system, and other measures, which strengthened the graduate students' ! independent study ability and scientific research quality. The related practice can provide reference for the development of information literacy education in colleges and universities.
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One of the major responsibilities for medical students is to save lives and to popularize emergency medical treatment knowledge for the masses of society.Based on research analysis,systemic training of cardiopulmonary resuscitation program including lectures,simulation education and social practice were performed for medical students.After practice activities,these students could proficiently apply the basic knowledge and skills of cardiopulmonary resuscitation in practical work and spread what they have learned to the public.Furthermore the program could improve students' abilities in social practice and team spirit and it is of great social significance.
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The animal experiment studies have demonstrated that hyperthermia is a strong teratogen to many kinds of animal with high incidence of neural tube defects(NTD).Epidermiological investigation showed that hyperthermia was closely related to the acencephaly and excenphaly in human being,but little was known about the distinct mechanism of NTD induced by hyperthermia.In order to study the developmental mechanism of NTD induced by hyperthermia,we observed the effects of hyperthermia on the neuroepithelial cells in primary culture.The neural tubes of the hamster embryos on 10 d after fertilization were obtained.the neuroepithelia were dissociated and then seeded at the density of 1×106 cells per well.The cells were divided into experimental and control groups randomly.The experimental groups were exposed to 42 C for 20 min,whereas groups exposed to 37 Cserved as control.After treatment of hyperthermia,the cells were incubated continuously at 37 C in a 95%air/5%CO2 humidified incubator,the culture was terminated after different intervals.Phase-contrast microscopy.scanning electron microscopy.transmission electron microscopy,MTT assay,agarose gel electrophoresis analysis,TUNEL detection,immunocytochemistryand image analysis were made.The results of the experimental groups indicated that the floating cells and apoptotic cells increased in number,the neurites of the cells were shortened even disappeared,the survival cells decreased in number,the ultrastructure of the cells demonstrated distinct abnormal changes,the function of mitochondria was impaired,the expressions of both bcl-2 and bax were abnormal.The above results suggest that hyperthermia may induce apoptosis of neuroepithelial cells,duringwhich bcl-2 and bax genes may play important regulatory roles.