Aim To study the effect of two racemic ketamine, S(+)-ketamine and R(-)-ketamine on stimulus-induced superoxide generation and intracellular calcium in vitro. Methods The stimulus-induced superoxide generation in human neutrophils was determined by using method of cytochrome C reduction. The intracellular calcium in human neutrophils was measured by chemiluminescence with Fura-2 loading. The phosphorylation of p47phox of NADPH oxidase in neutrophils was detected by Western blotting. Results S(+)-Ket and R(-)-Ket inhibited fMLP-induced superoxide generation in neutrophils in a concentration-dependent manner. In the case of PMA, S(+)-Ket inhibited PMA-induced superoxide generation and elevation of intracellular calcium of neutrophils in a concentration-dependent manner, whereas R(-)-Ket slightly increased PMA-induced superoxide generation and elevation of intracellular calcium of neutrophils. On the other hand S(+)-Ket inhibited the phosphorytion of p47phox of NADPH oxidase subunit,which R(-)-Ket was increased. EGTA can abolished the inhibition of S(+)-Ket on PMA-induced phosphorytion of p47phox.Conclusion S(+)-Ket inhibits the phosphorylation of p47phox of NADPH oxidase subunit and the superoxide generation in human neutrophils via PKC-calcium signal pathway.

Objective To investigate the risk factors for postoperative cognitive dysfunction (POCD)induced by patient-controlled intravenous analgesia(PCIA)in elderly patients. Methods 95 patients with POCD and 97 cognitive normal controls were included in the study. The cases and controls were matched for gender, type of operation and PCIA volume dose. Cognitive function was assessed by Mini-Mental-State test and the relationship between POCD and various factors was analyzed by univariate and multivariate analysis. Results Univariate analysis revealed that the education level and visual analog scale (VAS) score had significant differences between the two groups. Multivariate analysis showed that the VAS score and education level were significantly related to POCD induced by PCIA, with the odds ratios of 2. 379 (95%CI:1.205～4.698) and 0. 292 (95%CI:0.157～0.543), respectively. Conclusions Lower VAS score is an independent risk factor and higher education level seems to be a protective factor for POCD induced by PCIA.

Objective To investigate the effect of splenectomy on tau expression in rat hippocampus.Methods One hundred and five male SD rats aged 6 months weighing 350-400 g were randomly divided into 3 groups: group A control (n = 15); group B anesthesia (n =45) and group C surgery (n =45). The animals were anesthetized, intubated and mechanically ventilated. In group B and C the animals were anesthetized with 1.5% isoflurane for 2 h. In group C splenectomy was performed. The animals were killed on the 1st, 3rd and 7th day after anesthesia and surgery. The hippocampi were immediately removed for determination of IL-1 and TNF-α mRNA and protein expression, expression of total tau, phosphorylated tau at Thr-205 and Ser-396 and activity of glycogen synthase kinase-3 beta (GSK-3β). Results There was no significant difference in the expression of phosphorylated tau at Thr-205 and Ser-396 between control and anesthesia groups. Surgery significantly increased the expression of IL-1β and TNF-α and induced rapid and massive hyperphosphorylation of tau at Thr-205 and Ser-396 epitope in the hippocampus and activation of GSK-3β. Conclusion Surgical trauma induces inflammatory response in hippocampus, activates GSK-3β and increases phosphorylation of tau.

Objective To investigate the protective effect of hypoxic-preconditioned bone marrow mesenchymal stem cells (BMSCs) on spinal cord tissue after ischemia reperfusion injury.Methods Healthy adult Sprague Dawley (SD) rats weighing 200 ～ 250 grams (g) were randomly divided into 3 groups with 6 animals in each group:The sham group received simple surgical manipulation without ischemia/reperfusion treatment;The spinal cord ischemia/reperfusion group (Control group) only received spinal cord ischemia/reperfusion surgery.The hypoxic preconditioned BMSC transplantation group (HP-MSCs group) was injected with hypoxic preconditioned BMSCs 2 days before ischemia/reperfusion.The control group,HP-MSCs group received spinal cord ischemia/reperfusion for 10 min and observed for 48 h.The permeability of the blood-spinal cord barrier was examined with Evans blue (EB),and the histomorphology changes were observed with hematoxylin and eosin (HE) staining.Results EB red fluorescence was significantly weakened in the HP-MSCs group than that in the Control group (P ＜ 0.05),and more intact motor neurons were found in the lumbar spinal cords in the HP-MSCs group than that in the Control group (P ＜0.05).Conclusions The hypoxic-preconditioned BMSCs could effectively attenuate spinal cord ischemia reperfusion injury,it may be associated with protective effect of the blood-spinal cord barrier integrity.

Objective To investigate the effects of intrathecal transplantation of bone marrow stromal cells (BMSCs) on inter cellular cell adhesion molecule-1 (ICAM-1) expression and blood spinal cord barrier following spinal cord ischemia reperfusion injury.Methods Ninety Sprague Dawley rats were randomly divided into three groups:sham (Sham group),ischemia-reperfusion injury (I/ R group),and BMSCs transplantation (BMSCs group).Spinal I/R injury was induced by clamping the aortic arch between left common carotid artery and left subclavian artery for 14 min in I/R group and BMSCs group.Sham group was subjected to exposure of aortic arch but without occlusion.I/R group and BMSCs group were intrathecally injected with phosphate buffered saline (PBS) or BMSCs (2 × 106) two days before injury.At 1 d,3 d,and 7 d after injury,neurological function was evaluated and damaged lumbosacral seg ment was removed for measurement of blood spinal cord barrier permeability and ICAM-1 protein expression.Results Compared with Sham group,neurological function score was significantly lower:1 d (F =38:59,P =0.001),3 d (F =31.34,P =0.001),and 7 d (F =27.71,P =0.001) ; ICAM-1 expression was increased 1 d (F =34.33,P =0.001),3 d (F =29.76,P =0.001),and 7 d (F =23.65,P =0.001),and blood spinal cord barrier permeability was higher:1 d (F =42.57,P =0.001),3 d (F =32.75,P =0.001),and 7 d (F =26.89,P =0.001) in I/R group.Compared with I/R group,neurological function score was increased:1 d (F =16.62,P =0.001),3 d (F =21.54,P =0.001),and 7 d (F =12.84,P =0.002) ; ICAM-1 expression was decreased:1 d (F =19.84,P =0.018),3 d (F =17.38,P =0.008),and 7 d (F =22.46,P =0.007),and blood spinal cord barrier permeability was lower:1 d (F =22.38,P =0.016),3 d (F =27.59,P =0.009),and 7 d (F =23.25,P =0.001) in BMSCs group.Conclusions Intrathecal transplantation of BMSCs inhibited ICAM-1 expression and decreased blood spinal cord barrier permeability,and then attenuated spinal cord ischemia-reperfusion injury.

Objective To evaluate the effect of hypoxia-preconditioned bone marrow mesenchymal stem cells (BMSCs) on the expression of HO-1 during spinal ischemia-reperfusion (I/R) in rats.Methods Thirty healthy adult Sprague-Dawley rats,weighing 200-250 g,were randomly divided into 5 groups with 6 animals in each group using a random number table:sham operation group (group S),I/R group,PBS group,BMSC transplantation group (BMSC group) and hypoxic preconditioning group (group HP).In group HP,BMSCs were exposed to 3％O2-5％CO2-92％N2 for 24 h for hypoxia preconditioning.In PBS,BMSC and HP groups,PBS,BMSCs and BMSCs for hypoxic preconditioning were injected intrathecally,respectively,and 60 min later spinal I/R was induced by clamping the aorta in the rats anesthetized with chloral hydrate.At 6,12,24 and 48 h and 7 days of reperfusion,the neurological function was evaluated and scored.At day 7 of reperfusion,the rats were sacrificed,and spinal cord tissues were obtained for determination of HO-1 expression (by Western blot) and HO-1 mRNA expression (using real-time PCR).Results Compared with group S,the neurological function score was significantly decreased at each time point of reperfusion,and the expression of HO-1 mRNA and protein in spinal cord tissues was up-regulated in the other groups.Compared with group I/R,the neurological function score was significantly increased at each time point of reperfusion,and the expression of HO-1 mRNA and protein in spinal cord tissues was upregulated in BMSC and HP groups,and no significant change was found in group PBS in the parameters mentioned above.Compared with group BMSC,the neurological function score was significantly increased at each time point of reperfusion,and the expression of HO-1 mRNA and protein in spinal cord tissues was up-regulated in group HP.Conclusion The mechanism by which hypoxic preconditioning enhances protection of spinal cord by BMSC transplantation may be related to up-regulation of HO-1 expression in rats.

Objective:To investigate the effects of mesenchymal stem cells-derived exosomes (MSC-Exos) secreted by mesenchymal stem cells (MSCs) induced by astragaloside IV (AS-IV) on the biological function and pyroptosis of human umbilical vein endothelial cells (HUVECs) injured by high glucose.Methods:After human umbilical cord blood mesenchymal stem cells (hUCBMSCs) were intervened with 400 mg/L of AS-IV, exosomes were extracted, and then the morphology and specific markers of exosomes were identified. Human umbilical vein endothelial cells (HUVECs) were cultured in a medium with a glucose concentration of 30 mmol/L to prepare a high glucose-impaired HUVECs model. High glucose-impaired HUVECs were randomly divided into experimental and model groups, with the experimental group intervened with 100 μg/ml of MSC-Exos and the model group intervened with an equal volume of PBS solution, while a blank control group was also set up. Cell counting Kit-8 (CCK-8) cell proliferation assay, adhesion assay, matrigel tube formation assay and scratch assay were used to detect the effects of AS-IV-mediated MSC-Exos on the proliferation, adhesion, tube formation and migrationability of HUVECs; Western blot and real time fluorescence quantitative polymerase chain reaction (qRT-PCR) were used to detect the protein and mRNA expression of scorch death-related molecules, such as Caspase-1, GSDMD (Gasdermin D) and NLRP3 in each group.Results:The proliferation, adhesion number, tube number and migration width of HUVECs cells were significantly lower than those in the blank group ( P<0.05); The expression of Caspase-1, GSDMD, NLRP3 protein and their mRNA increased significantly ( P<0.001); Under the intervention of MSC-Exos mediated by AS-IV, the cell proliferation, adhesion number, tube number and migration width of HUVECs were significantly higher than those in the model group ( P<0.05); The expression of Caspase-1, GSDMD, NLRP3 protein and their mRNA decreased, with statistically significant difference ( P<0.05). Conclusions:AS-IV mediated MSC-Exos can significantly improve the biological function of high glucose-impaired endothelial cells, and its mechanism may be related to anti-pyroptosis.