1.Role of PI3K/Akt signaling pathway in dexmedetomidine postconditioning-induced reduction of myocardial ischemia-reperfusion injury in rats
Chinese Journal of Anesthesiology 2014;34(4):481-484
Objective To evaluate the role of phosphatidylinositol 3-kinase (PI3K)/protein-serinethreonine kinases (Akt) signaling pathway in dexmedetomidine postconditioning-induced reduction of myocardial ischemia-reperfusion (I/R) injury in rats.Methods Seventy-two healthy male Sprague-Dawley rats,aged 4-5 months,weighing 200-240 g,were heparinized and anesthetized with intraperitoneal pentobarbital sodium 40 mg/kg.Their hearts were rapidly excised and perfused in a Langendorff apparatus with oxygenated (95% O2-5% CO2) K-H solution at 0-4℃.The isolated hearts were randomly divided into 6 groups (n =12 each):control group (group C),group I/R,dexmedetomidine postconditioning group (gruop D),solvent group (group DMSO),PI3K inhibitor LY294002 group (group L) and LY294002 + dexmedetomidine postconditioning group (group L + D).After a 20 min stabilization period,the hearts were continuously perfused with K-H solution for 120 min in group C and were subjected to 30 min of global no-flow ischemia followed by 90 min of repeffusion in the other groups.Dexmedetomidine 100 nmo/L was added during the initial 30 min of reperfusion in D and L + D groups.LY294002 15 μmol/L was added in L group.0.02% DMSO containing 15 μmol/L LY294002 was added in L + D group.0.02% DMSO was added in DMSO group.HR,left ventricular end-diastolic pressure,left ventricular developed pressure and ± dp/dtmax were recorded at the end of 20 min stabilization and 15,30 and 90 min of reperfusion.The expression of phosphorylated Akt (p-Akt) and Akt was measured at 30 min of reperfusion.Myoeardial infarct size was determined using TTC staining at 90 min of reperfusion.Results Compared with group C,HR,left ventricular developed pressure and ± dp/dtmax were significantly decreased,and left ventricular enddiastolic pressure and myocardial infarct size were increased in the other 5 groups,and the expression of p-Akt was significantly up-regulated in group D (P < 0.05).Compared with group I/R,HR was significantly decreased at 15 and 30 min of reperfusion,the expression of p-Akt was up-regulated,and myocardial infarct size was decreased in group D (P < 0.05).Compared with group D,the expression of p-Akt was down-regulated,and myocardial infarct size and HR was increased in L + D group (P < 0.05).Conclusion Dexmedetomidine postconditioning attenuates myocardial I/R injury throuth activating PI3K/Akt signaling pathway in rats.
2.Interaction between nimodipine and growth factors during formation of new retinal vessels
Yi KONG ; Lirong HAN ; Yajun PENG ; Li TANG ; Changxiu CHEN
Academic Journal of Second Military Medical University 2000;0(07):-
Objective: To study the interaction between the calcium channel antagonist nimodipine and growth factors (vascular endothelial growth factor [VEGF] and platelet-derived growth factor[PDGF]) during the formation of new retinal vessels. Methods: The hyperoxia model was induced by proliferative retinopathy (OIR) in newborn Sprague-Dawley (SD) rats. SD rats (2 d after birth) were randomized into 5 groups: normal control group, pure OIR group and group 3, 4 and 5, where the animals received retrobulbar injection of nimodipine 10 ?l, 5 ?l and 2 ?l once every 2 d for 3 times, respectively. Both eyeballs of newborn rats were made into common pathological sections and detected by immunohistochemistry method to count the nuclei of proliferative retinal vessel cells and to investigate the expression of VEGF and PDGF in retina. Results: The nuclei of proliferative retinal vessel cells and the expressions of VEGF and PDGF in pure OIR group increased significantly compared to those of normal control group(P
3.The advance of bioactive peptide RGD in the research of bone regeneration.
Kai QIU ; Xin CHEN ; Tianquan LI ; Changxiu WAN
Journal of Biomedical Engineering 2003;20(3):546-549
Clinically, there has been so far no effective way to repair the bone-missing of large extent due to gash, infection and removal of tumor. The solution of this problem can be assisted by the addition of bioactive substances to substrate materials, because the growth of peripheral tissue and the fiber tissue growing the materials can be induced to the direction of bone-tissue by these biomaterials with bioactive peptides. The peptide Arg-Gly-Asp is the point between the integrin which comes from membrane and the ligand. In certain cases, the artificially synthesized RGD can be competitively combined with the integrin on cell surface, and outer-cell information is transmitted into cells, which will cause a series of physiological changes in cells. Presently, it is reported that the RGD has the ability to induce the growth of osteoblasts, restrain the adhesion between osteoclasts and substrates. This paper reviews and introduces the progress made with the work of RGD-inducing bone regeneration.
Biocompatible Materials
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Bone Regeneration
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drug effects
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physiology
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Cell Adhesion
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drug effects
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Oligopeptides
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administration & dosage
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chemistry
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pharmacology
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Osteoblasts
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drug effects
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physiology
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Osteoclasts
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drug effects
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physiology
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Tissue Engineering
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methods
4.Hierarchical chain management model in blood glucose control and its influence factors in patients with diabetes mellitus
Qingge GAO ; Yi WANG ; Chao SHI ; Rong CHEN ; Changxiu LIANG ; Yanrong LU ; Yong ZHOU
Chinese Journal of Postgraduates of Medicine 2012;35(19):7-10
Objective To explore the hierarchical chain management model in blood glucose control and its influence factors in patients with diabetes mellitus.Methods Health management database of diabetic patients was established in 2007 and managed by hierarchical chain management.The number of the patients reached to 1010 till 2011.The blood glucose control of diabetic patients was analyzed and its influence factors were analyzed by multivariate unconditional Logistic regression method.Results The concentration of glycosylated hemoglobin( HbA1c ) of 1010 patients with type 2 diabetes was (8.21 ±:2.70)%.Four hundred and eighty-seven cases (48.22%) reached the blood glucose standard,303 cases (30.00%)reached the blood pressure standard,245 cases (24.26%) reached the blood lipids standard,and 76 cases (7.52%) reached all three standards.Multivariate analysis showed that occupation (OR =2.521,95% CI:1.871 - 3.397),education level (OR =1.890,95% CI:1.642 - 2.174),disease course (OR =1.035,95%CI:1.016 -1.055),systolic pressure (OR =1.016,95% CI:1.007 -1.025) and triglyceride (OR =1.204,95%CI:1.063 - 1.365) were the risk factors of blood glucose control (P <0.01).Conclusions Hierarchical chain management model is helpful for the blood glucose control in patients with type 2 diabetes.The comprehensive control and treatment of type 2 diabetes should be taken combined with related risk factors,such as blood pressure,blood lipids and diabetes disease course.
5.Study and effect assessment of the hierarchical chain management model of type 2 diabetes
Qingge GAO ; Yi WANG ; Chao SHI ; Rong CHEN ; Changxiu LIANG ; Yanrong LU ; Yong ZHOU
Chinese Journal of Postgraduates of Medicine 2011;34(16):28-31
Objective To explore the hierarchical chain management model of type 2 diabetes and determine its evaluation.Method Based on the hierarchical chain management of the three community health service institutions and Dahua hospital in Shanghai Xuhui district,215 cases of type 2 diabetes had been involved in the study.Results Compared with the baseline before management,lasting blood glucose (FBG),2 h postprandial glucose (2hPBG),glycosylated hemoglobin (HbA1c),low density lipoprotein cholesterol (LDL-C),systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the diabetes after 12 months' management declined [(8.50 ±2.81) mmol/L,(11.09 ±4.01) mmol/L,(8.56 ±2.41)% ,(3.31 ± 1.06) mmol/L,(139.06 ±20.68) mm Hg (1 mm Hg = 0.133 kPa),(78.20 ± 12.11) mm Hg vs.(7.41 ±2.04) mmol/L,(9.03 ±2.46) mmol/L,(7.34 ± 1.59)% ,(3.00 ± 1.06) mmol/L,(135.48 ± 17.82) mm Hg,(77.27 ±11.83) mm Hg],and the differences were statistically significant(P<0.01 );control rate of FBG,2hPBG,HbA1c,LDLC,SBP,DBP had improved significantly [19.5% (42/215),20.9% (45/215),24.7%(53/215),20.0%(43/215),27.4%(59/215),30.2%(65/215) vs.50.7%(109/215),53.0% (114/215),54.0%(ll6/215),42.3%(91/215),47.0%(101/215),45.6%(98/215)](P<0.01).Conclusion Primary and secondary-care hospital based hierarchical chain management model is valid and can be implemented for type 2 diabetes.
6.Influencing factors of standardization in the hierarchical chain management of type 2 diabetes
Yi WANG ; Qingge GAO ; Xiangying MENG ; Yanrong LU ; Chao SHI ; Rong CHEN ; Changxiu LIANG ; Yong ZHOU
Clinical Medicine of China 2012;28(12):1264-1268
Objective To analysis the influence factors of standardization in the hierarchical chain management of type 2 diabetes and to enhance the hierarchical chain management of type 2 diabetes.Methods ( 1 ) Six hundred and ninty patients with type 2 diabetes completed 1 years management were divided into well-controlled glycosylated hemoglobin ( HbAlc ) group (<7.0% ) and bad-controlled glycosylated hemoglobin (HbAlc) group ( ≥ 7.0% ).The conditions of diet,physical activity,medication,self-blood sugar monitoring and participation in health seminars were investigated and analyzed.(2) The patients were divided into standardized management group and not standardized management group.Their age,sex,educational background,occupation,monthly income per person,medical security,the course,cognition for glycuresis,two-way transfer,and chronic complications were investigated and statistically analyzed.Results ( 1 ) The proportions of physical activity (70.1% vs 54.2%,x2=6.163,P=0.018),self-blood sugar monitoring(60.4% vs 43.8%,x2=6.268,P=0.016) and participation in health seminars (56.0% vs 41.7%,x2=4.577,P=0.045) in the well-controlled HbAlc group were significantly higher than those in the bad-controlled HbAlc group.(2) Their age [(61.08 ±10.04) years old vs ( 57.75 ± 9.89 ) years old,t=2.539,P=0.012],educational background ( ratio of low educational attainment:8.3 % vs 17.2%,x2=6.426,P=0.041 ),medical security (own expense ratios:4.6% vs 11.5%,x2=3.543,P=0.048 ),awareness of diabetes ( ratio of poor awareness of diabetes:19.4% vs 41.0%,x2=17.518,P=0.000 ),two-way transfer ( ratio of not transfer treatment:4.6% vs 14.8%,x2=7.662,P=0.022) and chronic complications ( ratio of chronic complication:41.7 % vs 26.2%,x2=6.130,P=0.017) were significantly different between the standardized management group and not standardized management group.(3) Logistic regression analyses indicated that the age ( OR=0.954,P=0.006),monthly income per person ( OR=4.101,P=0.018 ),medical security ( OR=7.617,P=0.003 ),cognition for glycuresis ( OR=0.030,P=0.000),two-way transfer ( OR=9.079,P=0.000) and chronic complications ( OR=0.456,P=0.031 ) were the risk factors of standardized management.Conclusion We should focus on the impact factors affecting the standardized management of patients including age,monthly income per person,medical security,awareness of diabetes,ratio of not transfer treatment,positive strategies for chronic complications,improve the hierarchical chain management of type 2 diabetes,and then make the diabetic patients to early participate in standardization management of diabetes mellitus and delay the appearance of complications.
7.The hydrophilicity and cell affinity of polylactic acid containg bionic function group of phosphorylcholine.
Juan LUO ; Lijian WANG ; Yuanwei CHEN ; Xianglin LUO ; Nianchao CHEN ; Changxiu WAN ; Xiaohua ZHANG
Journal of Biomedical Engineering 2008;25(6):1344-1348
A series of novel biodegradable and bionic functional polymers, PLLA-PC-PLLA, were synthesized using L-lactide ring-opening polymerization by L-a-Glycerophosphorylcholine (PC) from nature source. The hydrophilicity of the polymers was investigated. The results made known that, as PC group was brought into the backbone of PLLA, PLLA-PC-PLLA gained much better hydrophilicity than did PLLA, and polar phosphatidylcholines probably transferred to the sample surface in aqueous environment. The relative growth ratios of ECV304 cells to the lixivium of all PLLA-PC-PLLA were higher than 84% in 5 d culture. The cells adhesion of ECV304 on the films of PLLA-PC-PLLA lagged as compared to that on PLLA, but they could proliferate and cover the films in total. The difference between PLLA-PC-PLLA and PLLA was due to the existence of PC group. Thus, PLLA-PC-PLLA, the same as PLLA, are not cytotoxic, and ECV304 can attach and proliferate on them. PLLA-PC-PLLA have potential applications in the fields of tissue engineering and drug delivery system.
Cell Adhesion
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physiology
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Drug Carriers
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Endothelial Cells
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cytology
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Humans
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Hydrophobic and Hydrophilic Interactions
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Lactic Acid
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chemistry
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pharmacology
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Phosphorylcholine
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chemistry
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pharmacology
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Polyesters
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Polymers
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chemistry
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pharmacology
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Surface Properties
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Tissue Scaffolds
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Umbilical Veins
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cytology
8.Advances in research on calcium polyphosphate bioceramic for bone tissue engineering scaffold.
Kai QIU ; Xin CHEN ; Changxiu WAN
Journal of Biomedical Engineering 2005;22(3):614-617
Bone tissue engineering is a novel, developing and challenging science which provides a new way to repair bone lost from injury and disease. Porous calcium polyphosphate bioceramic is one kind of absorptable bioceramic. Owing to its fine biocompatibility and degradability, more and more pieces of research wark have been carried out in bone tissue engineering, and because of its special characteristics, calcium polyphosphate bioceramic is regarded as a promising material for solving the problem of how to match the degradation velocity of scaffold with the velocity of cell growth. The recent research of using calcium polyphosphate bioceramic as the scaffold in bone tissue engineering is summarized, including the property, synthesis and advances.
Bone Substitutes
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chemistry
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Bone and Bones
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Calcium Phosphates
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chemistry
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Humans
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Porosity
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Tissue Engineering
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Tissue Scaffolds
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chemistry
9.The advance in researches for biomedical intelligent polymer materials.
Zhibin ZHANG ; Changwei TANG ; Kai QIU ; Yuanwei CHEN ; Yanfang XIONG ; Changxiu WAN
Journal of Biomedical Engineering 2004;21(5):852-855
The properties of biomedical intelligent polymer materials can be changed obviously when there is a little physical or chemical change in external condition. They are in the forms of solids, solutions and polymers on the surface of carrier, including aqueous solution of hydrophilic polymers, cross-linking hydrophilic polymers (i.e. hydrogels) and the polymers on the surface of carrier. In this paper are reviewed the progress in researches and the application of biomedical intelligent polymer materials.
Biocompatible Materials
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chemistry
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Biotechnology
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Chemical Phenomena
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Chemistry, Physical
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Hydrogel, Polyethylene Glycol Dimethacrylate
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chemistry
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Polymers
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chemistry
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Surface Properties
10.Effect of processing parameters on the degradation of calcium polyphosphate bioceramic for bone tissue scaffolds.
Yingjie QIN ; Xixun YU ; Yuanwei CHEN ; Yulong DING ; Changxiu WAN
Journal of Biomedical Engineering 2007;24(4):794-797
This study was undertaken to elucidate the degradation regularity of calcium polyphosphate (CPP) scaffolds with different preparation parameters. CPP scaffolds with different main crystalline phases were prepared by controlling the particle size of the calcining stuff and the calcining heat. Specimens were soaked into Tris-buffer solution and simulated body fluid (SBF) for 60 days. Results show: alpha-CPP degrades faster than does beta-CPP, and beta-CPP degrades faster than does gamma-CPP; the lower the sinter temperature, the better the degradation of CPP morever, the degradation rate of CPP is inversely proportional to the original particle size. These data suggest that crystal type, sinter temperature and particle size influence the degradation rate of CPP markedly.
Absorbable Implants
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Biocompatible Materials
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chemistry
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Bone Substitutes
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chemistry
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Calcium
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chemistry
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Calcium Phosphates
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chemistry
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Ceramics
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chemistry
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Polymers
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chemistry
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Polyphosphates
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chemistry
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Tissue Scaffolds
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chemistry