Objective To evaluate the effect of sevoflurane preconditioning on autophagy during ischemiareperfusion (I/R) injury to isolated rat hearts and the role of PI3K/Akt signaling pathway.Methods Healthy adult male Wistar rats,aged 6-8 weeks,weighing 250-280 g,were anesthetized.Their hearts were excised and perfused in a Langendorff apparatus.Eighty-four isolated rat hearts with I/R injury were randomly divided into 7 groups (n =12 each):normal control group (NC group),I/R group,sevoflurane preconditioning group (S + I/R group),normal control plus wortmannin group (NC + W group),I/R plus wortmannin group (I/R + W group),sevoflurane preconditioning plus wortmannin group (S + I/R + W group),and solvent group (S + I/R + D group).In NC group,the hearts were continuously perfused with K-H solution for 180 min.In I/R group,the hearts were perfused with K-H solution for 30 min,and then subjected to ischemia for 30 min followed by 120 min of reperfusion.In S+ I/R group,the hearts were perfused with K-H solution for 10 min,and then with K-H solution saturated with 2.5％ sevoflurane for 15 min,followed by 5 min washout with K-H solution before ischemia.In NC + W group,wortmannin (PI3K inhibitor) 15 μg/kg was injected intraperitoneally at 30 min before chest opening,and the other procedures were similar to those previously described in group NC.In I/R + W group,wortmarnin 15 μg/kg was injected intraperitoneally at 30 min before chest opening,and the other procedures were similar to those previously described in group I/R.In S + I/R + W group,wortmannin 15 μg/kg was injected intraperitoneally at 30 min before chest opening,and the other procedures were similar to those previously described in S + I/R group.In S + I/R + D group,dimethyl sulfoxide 1.5 ml/kg was injected intraperitoneally at 30 min before chest opening,and the other procedures were similar to those previously described in group S + I/R.The HR,± dp/dtmax,left ventricular developed pressure (LVDP) and left ventricular end-diastolic pressure (LVEDP) were recorded at the end of equilibration and reperfusion.At the end of reperfusion,coronary effluent was collected to detect lactate dehydrogenase (LDH) activity,and myocardial specimens were obtained to calculate the percentage of myocardial infract size.The expression of autophagy marker LC3-Ⅱ and Akt,phosphor-Akt (p-Akt),mammalian target of rapamycin (mTOR),and phosphor-mTOR (p-mTOR) was determined by Western blot.Results Compared with NC group,no significant change was found in the parameters of hemodynamics in NC + W group,and HR,± dp/dtmax and LVDP were significantly decreased,LVEDP,myocardial infract size,and LDH activity were increased,LC3-Ⅱ expression was up-regulated,and the expression of p-Akt and p-mTOR was down-regulated in the other groups.Compared with group I/R,HR,± dp/dtmax,and LVDP were significantly increased,LVEDP,myocardial infract size,and LDH activity were decreased,LC3-Ⅱ expression was downregulated,and the expression of p-Akt and p-mTOR was up-regulated in S + I/R and S + I/R + D groups,and no significant change was found in each parameter in S+ I/R+ W group.Compared with S + I/R group,HR,± dp/ dtmax and LVDP were significantly decreased,LVEDP,myocardial infract size and LDH activity were increased,LC3-Ⅱ expression was up-regulated,and the expression of p-Akt and p-mTOR was down-regulated in S + I/R + W group,and no significant change was found in each parameter in S + I/R + D group.Conclusion Sevoflurane preconditioning can decrease autophagy of myocardial cells during I/R through activating PI3K/Akt signaling pathway and enhancing mTOR activity in the downstream,thus protecting isolated rat hearts against I/R injury.

Atropine (Atr) ip 5 - 10mg/kg elevated the threshold dose of ouabain ( 10?g/min, iv ) to induce ventricular premature beats, ventricular tachycardia , ventricular fibrillation and cardiac arrest in guinea-pigs. Atr 2 - 4 mg/kg iv shortened the duration of arrhythmia elicited by Adr ( 40?g/kg, iv ) in conscious rabbits, & delayed the onset of arrhythmia evoked by AC ( 20?g/kg, iv ) or BaCl2 ( 2mg/kg, iv ) in anesthetized rats. It also decreased the incidence of arrhythmia induced by CaCl2 ( 102mg/kg, iv ) in rats. In mice, Atr ( 5~10mg/kg, ip)decreased the incidence of ventricular fibrillation by chloroform and artrial fibrill-ation ( or flutter ) by Ach-CaCl2.

AIM: To explore the effect of protein kinase C-?(PKC-?) in U937 cell line inhibited by short hairpin RNA(shRNA) on the transcription of vascular endothelial growth factor(VEGF) mRNA induced by stromal cell-derived factor-1(SDF-1).METHODS: 64 bp reverse repeated motifs of PKC-? target sequence were synthesized and inserted into the plasmid to construct the plasmid expressing shRNA-PKC-?(pSIRENp) and the pSIRENp plasmid was transfected into U937 cell line.The expression of PKC-? and VEGF mRNA was detected by RT-PCR.RESULTS: The recombinant plasmid pSIRENp was successfully constructed and it nearly completely suppressed the PKC-? expression in U937 cell line.After transfection,both basical and VEGF mRNA induced by SDF-1 significantly reduced compared to control.CONCLUSION: The results shows that the short hairpin RNA of PKC? efficiently reduces its expression in U937 cells and PKC-? may be involved in the regulation of VEGF mRNA expression.

Objective: To develop the matrix-matched calibration curve correction-inductively coupled plasma mass spectrometry (ICP-MS) for the determination of lead in blood. Methods: Whole blood samples and blank whole blood were pretreated by direct dilution with a solution of 0.5% nitric acid and 0.01% TritonX-100 to obtain whole blood sample solutions and matrix-matched solvents at a 10-fold dilution. The mass concentration of lead was determined by using an ICP-MS instrument in He mode. 175Lu was added online as an internal standard. The standard working curve was calibrated with the matrix-matched solvent, and the mass concentration of lead in the whole blood samples was calculated based on the standard working curve. Recovery tests were performed on whole blood blind samples by spiking, and the relative standard deviation and average recovery rate were calculated. The accuracy and precision of this method were assessed by comparing it with the method recommended in the national standard in detection of lead in three types of bovine blood lead standard materials. Results: Good linearity was shown for lead at 0.5 to 100.0 μg/L, with a correlation coefficient of 1.000. The detection limit of lead was 0.4 μg/L, and the quantitation limit was 1.3 μg/L. The relative standard deviations were 0.65% and 1.10%. The average recovery ranged from 96.89% to 99.73%. The lead determination results were all within the normal reference ranges specified by the three certified reference materials for bovine blood samples. Conclusion The matrix-matched calibration curve correction-ICP-MS is suitable for high-throughput determination of blood lead.

Aim To determine the effects and mechanisms of isoflurane on energy metabolism during ischemia and reperfusion in isolated rat hserts.Methods The rat Langendorff model was used,and isolated per-fused rat hearts were separated into untreated,isoflurane,chelerythrine(PKC inhibitor)plus isoflurane,and chelerythrine groups.All the hearts were subjected to treatment before ischemia,followed by 30 min of ischemia and 60 min of reperfusion.Hemodynamic variables were recorded,and metabolites were measured by high-performance liquid chromatography,and analyzed subcellular localization of PKC isoforms by Western blot analysis.Results The recovery of left ventricular developed pressure after ischemia was(33?8)%,(56?9)%,and(30?5)% in the untreated,isoflurane,and isoflurane with chelerythrine groups respectively.Compared with the untreated hearts,isoflurane significantly improved the recovery of left ventricular developed pressure(P

Objective To investigate the role of phosphatidyl-inositol 3-kinase-Akt (PI3k-Akt) signal pathway in the attenuation of ischemia-reperfusion (I/R) injury by sevoflurane preconditioning in isolated rat hearts. Methods Ninety-six adult male SD rats weighing 220-280 g were randomly divided into 6 groups ( n = 16 each): sham operation group (group S); I/R group; sevoflurane preconditioning group (group SP); wortmannin group (group W); dimethyl sulfoxide (DMSO) group (group D) and sevoflurane preconditioning + wortmannin group (group SW) . Their hearts were excised and perfused in a Langendorff apparatus with K-H solution saturated with 95%O2-5%C02 at 37 ℃ . The hearts were continuously perfused for 180 min in group S. After 15 min of equilibration, the isolated hearts were subjected to 30 min of ischemia followed by 120 min of reperfusion in SP, W, D and SW groups. Croups SP, W, D and SW received 10 min of perfusion with K-H solution containing 2. 4% sevoflurane, 100 nmol/L wortmannin, 20 μmol/L DMSO, and 2.4% sevoflurane + 100 nmol/L wortmannin, respectively, followed by 5 min washout before I/R. Eight hearts in each group were selected and HR, left ventricular end-diabetic pressure (LVEDP), left ventricular developed pressure (LVDP), and ± dp/dtmax were recorded at the end of equilibration and at 15 min of reperfusion, Myocardial tissues were obtained at 15 min of reperfusion for determination of apoptosis (by TUNEL) and phosphorylated Akt (p-Akt) expression (by Western blot) . Another 8 hearts were selected at 120 min of reperfusion for determination of myocardial infarct size by TTC staining. Result Compared with group S, LVDP and ± dp/dt,^ were significantly decreased and LVEDP was significantly increased in groups I/R, SP, W, D and SW, and myocardial p-Akt expression was up-regulated in groups I/R, SP and D ( P ＜ 0.05). Compared with group I/R, LVDP and ± dp/dtmax were significantly increased, LVEDP and apoptosis index were significantly decreased, myocardial p-Akt expression was up-regulated, and myocardial infarct size was significantly reduced in group SP (P ＜0.05) . Conclusion Activation of PI3K-Akt signal pathway is involved in the attenuation of I/R injury by sevoflurane reconditioning in isolated rat hearts.

Objective To study the effect of Sandra Fucile oral stimulation on oral feeding readiness and ability of preterm infants.Methods Sixty-five premature infants were selected in the study.All of the premature infants were recruited randomly in convenience between Jul.and Dec.2012.For a randomized control principle,SPSS 13.0 was performed to achieve complete random design.Objects were divided into control group(receiving routine nursing) and intervention group(on the basis of routine nursing,receiving 15 minutes oral stimulation,1 time/day,for 10 days).Chinese version of Preterm Infant Oral Feeding Readiness Assessment scale(PIOFRA scale-CV) was used when intervention began,and 7 days,10 days,14 days after the start of the intervention.Results PIOFRA-CV scale score was statistically different at different time in both groups(F =169.062,P ＜0.001).The first day ratings were minimum in the 2 groups,after which with an upward trend over time.The control group and intervention group rated a statistically significant difference(F =5.538,P =0.022).Except for no difference on the first day and seventh day (t =1.650,P =0.204 ;t =0.817,P =0.369) between the 2 groups,the intervention group had a higher score than the control group (t =17.339,24.141,all P ＜0.001).Group and time had an interaction effect(F =1 1.561,P ＜0.001).The incidence of vomiting[42.4％ (14/33 cases) vs 34.4％ (11/32 cases)],infection [27.3％ (9/33 cases) vs 9.4％ (3/32 cases)],and gastro-oesophageal reflux[30.3％ (10/33 cases) vs 25.0％ (8/32 cases)] were not significantly different between the 2 groups(x2 =0.445,3.457,0.288,all P ＞ 0.05).Conclusions Saudra Fucile oral stimulation method can significantly promote the development of premature oral feeding ability on the 10 day after the intervention,and will not increase vomiting,gastroesophageal reflux,and infection.It is suitable for clinical application.

Objective To investigate the effect of sevoflurane postconditioning on mitochondrial connexin 43 (Cx43) during myocardial ischemia-reperfusion (I/R) in isolated rat hearts and the role of mitochondrial ATP-sensitive potassium (mito-KATP) channels in it.Methods Forty-five adult male SpragueDawley rats,weighing 200-250 g,were used in the study.Their hearts were excised and retrogradely perfused with K-H solution in a Langendorff apparatus.The 45 isolated hearts were assigned into 5 groups (n =9 each) using a random number table:control group (group C),I/R group,sevoflurane postconditioning group (group Sev),and sevoflurane postconditioning plus 5-hydroxydecanoate (5-HD,a specific mitoKATp channel blocker) group (group Sev+5-HD) and I/R plus 5-HD group (group I/R+5-HD).The hearts were subjected to 20 main of global ischemia followed by 90 min of reperfusion to establish the model of myocardial I/R injury.From the beginning of reperfusion,the hearts were perfused with K-H solution saturated with 3％ sevoflurane for 15 min in group Sev,with K-H solution saturated with 3％ sevoflurane and containing 100 μ mol/L 5-HD in group Sev+5-HD,and with K-H solution containing 100 μ mol/L 5-HD in group 5-HD.The heart rate (HR),left ventricular end-diastolic pressure (LVEDP),left ventricular developed pressure (LVDP) and the maximum rate of increase and decrease of ventricular pressure (±dp/dtmax) were recorded at the end of equilibration (T1) and 30 and 60 min of reperfusion (T2,3).At 90 min of reperfusion,the myocardial infarct size was measured by TTC staining,and the expression of total Cx43 (tCx43)and phosphorylated Cx43 (p-Cx43) in mitochondria was determined by Western blot analysis.The percentage of myocardial infarct size and p-Cx43/tCx43 ratio were calculated.Results Compared with group C,the HR,LVDP and ±dp/dtmax were significantly decreased,and the LVEDP was increased at T2,3,and the percentage of myocardial infarct size was increased in the other 4 groups,the expression of mitochondrial tCx43 and p-Cx43 was significantly down-regulated in I/R,Sev+5-HD and 5-HD groups (P＜0.05),and no significant change was found in the expression of mitochondrial tCx43 and p-Cx43 in group Sev (P＞0.05).Compared with group I/R,the HR,LVDP and ±dp/dtmax were significantly increased,and the LVEDP was decreased at T2,3,the percentage of myocardial infarct size was decreased,and the expression of mitochondrial tCx43 and p-Cx43 was up-regulated in group Sev (P＜0.05),and no significant change was found in the parameters mentioned above in Sev+5-HD and 5-HD groups (P＞0.05).Compared with group Sev,the HR,LVDP and ±dp/dt were significantly decreased,and the LVEDP was increased at T2,3,the percentage of myocardial infarct size was increased,and the expression of mitochondrial tCx43 and p-Cx43 was down-regulated in group Sev+5-HD (P＜0.05).There was no significant change in the pCx43/tCx43 ratio between the five groups (P＞0.05).Conclusion The mechanism by which sevoflurane postconditioning attenuates myocardial I/R injury may be related to induction of mito-KATP channel opening and up-regulation of the expression of mitochondrial Cx43 in cardiomyocytes of rats.

Objective To investigate the relationship between hypoxia and stemness of cancer stem cells ( CSCs ) . Methods U87 cells,U251 cells and primary glioma cells were experienced hypoxia. Detected the ultrastructure of these cancer cells with transmission elec-tron microscopy;detect the cell growth with MTT assay;cell cycle and CD133 expression were detected by flow cytometry;and the cell mi-gration ablity were detected through transwell chamber assay;the colony-forming efficiency were deteced by colony-forming assay; and real-time quantitative PCR and Western blot were carried out to detect the mRNA and protein expression of markers of stem cells and their differ-entiation respectively. Results Hypoxia maintained the undifferentiated state of primary glioma cells, slowed down the growth of glioma cells which were in a relatively quiescent stage, increased the colony forming efficiency and migration of glioma cells, and increased the expression of markers of stem cells, but the expression of markers for stem cell differentiation was reduced after hypoxia treatment. Conclusion Hypoxi-a may induce the “dedifferentiation” of differentiated glioma cells which then acquire the stemness.