west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "Calcium" 67 results
  • Effect of Verapamil on Apoptosis, Calcium and Expressions of bcl-2 and c-myc of Pancreatic Cells in Ischemia-Reperfusion Rat Model

    【Abstract】 Objective To investigate the effect of verapamil on apoptosis, calcium and expressions of bcl-2 and c-myc of pancreatic cells in ischemia-reperfusion rat model. Methods Wistar rats were randomly divided into three groups: control group (n=10); ischemia-reperfusion group (n=10); verapamil treatment group (n=10). The anterior mesenteric artery and the celiac artery of rats in both ischemia-reperfusion group and verapamil treatment group were occluded for 15 min followed by 12-hour reperfusion. Verapamil (1 mg/kg) was injected via caudal vein to the rats in verapamil treatment group 15 min before occlusion and 1 hour after the initiation of reperfusion, respectively; and ischemia-reperfusion group was given the same volume of salient twice intravenously. Pancreatic tissues were collected from the dead rats after twelve hours since the reperfusion. The pathologic characters of pancreatic tissue were observed under light microscope; The level of calcium in the tissue was measured by atomic absorption spectrometer; TUNEL was used to detect apoptosis of pancreatic cells; and the expressions of c-myc and bcl-2 in the cells were also analyzed by immunohistochemistry technique and flow cytometry. Results The pathologic change in verapamil treatment group was less conspicuous than that of ischemia-reperfusion group. Both the calcium level and the number of apoptotic cells in verapamil treatment group were less than those of ischemia-reperfusion group 〔(411.1±55.8) μg/g dry weight vs (470.9±31.9) μg/g dry weight, P<0.05 and (9.5±2.9)% vs (18.4±3.1)% 〕, P<0.05. After taking verapamil, the number of apoptotic cells decreased, whereas the expressions of bcl-2 and c-myc increased. The fluorescent indexes of bcl-2 and c-myc in verapamil treatment group were significantly higher than those of ischemia-reperfusion group (1.72±0.11 vs 1.41±0.07, P<0.05; 1.76±0.19 vs 1.55±0.13, P<0.05. Conclusion Ischemia-reperfusion injury can induce apoptosis of pancreatic cells. Verapamil could protect the injured pancreatic tissue by reducing the level of calcium, stimulating the expressions of bcl-2 and c-myc and inhibiting apoptosis of pancreatic cells.

    Release date:2016-09-08 11:53 Export PDF Favorites Scan
  • PRODUCT STANDARD AND QUALITY CONTROL OF MEDICAL ALGINATES

    Objective To compare product standards of drug and medical device made from sodium alginate and calcium alginate between domestic and abroad, and to emphases on the process parameters monitoring based on different standards. Methods Sodium alginate and calcium alginate standards of both domestic and foreign were analyzed and summarized, and the differences and commonalities of various product standards among each standard were compared. Results Differences exist in product standards of sodium alginate and calcium alginate between domestic and abroad, whether drug or medical device, but the fundamental control points are concordant. Conclusion Companies should focus on product quality control requirements combined with its own unique manufacturing process characteristics to develop reasonable and controllable quality standards, which can ensure safe and effective clinical use.

    Release date:2016-08-31 04:07 Export PDF Favorites Scan
  • Effect of Substance P on Intracellular Free Calcium Concentration in Cultured Gastric Cancer Cell in Vit ro

    Objective  To study the effect of substance P ( SP) on int racellular f ree calcium concent ration in human poorly-differentiated gast ric cancer cell in vitro. Methods  Human gast ric cancer cell line MKN45 was cultured in RPMI 1640. Then the cells were loaded with specific calcium fluorescent probe Furu23/ AM. ASN21377642 (NK21 receptor antagonist) , Nicardipine (calcium channel blocker) and different concent rations of SP were used to treat gast ric cancer cells. The concent ration changes of int racellular free calcium were detected by laser scanning confocal microscope. Results  It was found that 10 , 50 and 100 nmol/ L SP could significantly increase the int racellular free calcium concent ration of gast ric cancer cells in Hanks solutions , which contain ext racellular calcium ( P lt;0. 05) , and the change was in a dose-dependent manner ( P lt; 0. 05) . When there was ext racellular calcium existed ,the increasing amplitude of intracellular f ree calcium concent ration was significantly higher than that when there was no extracellular calcium ( Plt; 0. 05) . And when Hanks solutions were pretreated with ASN21377642 and Nicardipine , the effects of 100 nmol/ L SP were partly inhibited , and the concent rations of int racellular f ree calcium were significantly lower than those in group s without pret reatment s ( P lt; 0. 05) . Conclusion  SP can significantly increase free calcium concent ration in the gastric cancer cells. Releasing of stored calcium in the cells and influx of extracelluar calcium may contribute to the elevation of int racellular free calcium concentration.

    Release date: Export PDF Favorites Scan
  • IMPLANTATION OF ALLOGENIC OSTEOBLAST COMBINED WITH CALCIUM PHOSPHTA COMPOSITES

    The aim of this experiment was to study the osteogenesis in vivo of allogenic osteoblast combined culture with calcium phosphate composites. The osteoblasts were obtained by enzymatic digestion of periosteum from fibula subcultured to 13 generations, the cells were combined culture with hydroxyapatite and biphasic calcium phosphate. Subseguently, the composite was implanted into rabbits subcutaneously or intramuscularly. The blank material was implanted in the contralateral side as control. Four weeks later, all animals were sacrificed. All the implants were examined by gross observation, histological examination and EDXA. The results showed: 1. obvious ingrowth of connective tissue with very little inflammatory reaction; 2. new bone formation in the composites with deposit of Ca and P on the surface of osteoblast, but none in the blank materials; 3. no significant difference of new bone formation between the different sites of implantation or different materials, but those implanted intramuscularly had lamellae form of new bone while those implanted subcutaneously had only mineralization of extracellular matrix. The conclusion were: 1. the composites are biocompatible with prior osteogenesis property; 2. periosteal-derived allogenic osteoblasts obatined by enzymatic digestion could survive following implantation with bioactivity; 3. rich blood supply might be advantageous to new bone formation and its maturation.

    Release date:2016-09-01 11:08 Export PDF Favorites Scan
  • THE DETERMINATION OF INTRACELLULAR FREE Ca2+ CONCENTRATION OF DISSOCIATED RABBIT RETINA CELLS BY Fura-2/AM

    PURPOSE:To approach the establishment of t be optimal method for determining the intracellular free Ca2+ concentration[Ca2+]i of dissociated newborn rabbit retina cells by using fluorescent indicator-Fura-2/AM. METHODS:Trypsin was employed to prepare the retlna cell suspensions which were then loaded with Fura-2/AM followed by fluorescence determination. RESULTS:The cellular viability rate of retina cell suspensiotls prepared by 0.05% trypsin 10 minutes at 37deg;C was over 90%. Loading the retina cell suspensions with Fura-2/AM 40 minutes at 37deg;C and then measurlng the fluorescent intensity of the suspensions within 30 minutes were proved to be the optimum. CONCLUSIONS:The resting [Ca2+]i of retina cell suspension was (223plusmn;27)nmol/L whlch was within the expected range of [Ca2+]i level. 25mmoI/L and S0mmol/L K+ increased the [Ca2+Ji 59% and 148% respectively. These results indicate that the preparation of retina cell suspensions and the method of [Ca2+Ji determination are reliable and feasible. (Chin J Ocul Fundus Dis,1996,12: 108-110 )

    Release date:2016-09-02 06:21 Export PDF Favorites Scan
  • DETERMINATION OF INTRACELLULAR CALCIUM IONS IN FIBROBLASTS OF CONTRACTURED SCAR

    Free calcium ions, as a kind of message-transport substance, is important in cellular activity such as cell movement, cell differentiation and cell proliferation. In order to investigate the relationship between free calcium ions and scar contracture, the fibroblasts which originated from hypertrophic scar, keloid and normal skin were used as the experimental target. The fibroblasts from 4th-6th generations of different sources were used; Then the intracellular free calcium ions concentrations were measured respectively by the fluorescent Ca2+ indicator Fura-2/AM and Image analysis system. The results showed that the level of Ca2+ in fibroblasts of hypertrophic scar was higher than that in keloid and normal skin (P lt; 0.01). There was no significant difference between the level of Ca2+ in keloid and in normal skin. The conclusion was that the concentration of intracellular free calcium ions played an important role in the scar contract, but the exact mechanism was still unclear and required further study.

    Release date:2016-09-01 11:07 Export PDF Favorites Scan
  • EFFECT OF IMPROVING THE PANCREATIC ISCHEMIA AND CALCIUM CHANNEL BLOCKERS ON PREVENTING THE PROGRESSION OF ACUTE PANCREATITIS

    【Abstract】Objective To investigate the protective effect of improving the pancreatic ischemia and calcium channel blockers on preventing the progression of acute pancreatitis. Methods Twenty-four patients with mild acute pancreatitis were randomly divided into two groups: control group and treated group. Within the first 72 hours from the onset of AP, routine conservative managements were performed in control group, improving the pancreatic ischemia and preventing Ca2+ overload were performed in treated group for two weeks. The hemorrheological parameters were measured at 1,4,7,14 days after adimission, simultanously, serum TNFα, IL-1β, C-reactive protein and plasma TXB2, 6-keto-PGF1α levels were determined with ELISA methods. Results The hemorrheological changes were improved in treated group, serum TNFα, IL-1β, C-reactive protein and plasma TXB2, 6-keto-PGF1α levels were significantly decreased each time point in treated group as compared with control group. Conclusion Improving the pancreatic ischemia and calcium channel blockers have protective effect through reducing the generation of cytokines and inflammatory mediators on preventing the progression of acute pancreatitis.

    Release date:2016-08-28 05:30 Export PDF Favorites Scan
  • BALLOON VERTEBROPLASTY COMBINED WITH SHORT-SEGMENT PEDICLE SCREW INSTRUMENTATION FOR TREATMENT OF THORACOLUMBAR BURST FRACTURES

    ObjectiveTo investigate the short-term effectiveness of balloon vertebroplasty combined with short-segment pedicle screw instrumentation for the treatment of thoracolumbar burst fractures. MethodsBetween June 2011 and December 2013, 22 patients with thoracolumbar burst fractures were included. There were 14 males and 8 females, aged 20-60 years (mean, 42.5 years). The fracture segments included T11 in 1 case, T12 in 4 cases, L1 in 10 cases, L2 in 6 cases, and L3 in 1 case. According to AO classification system, there were 13 cases of type A and 9 cases of type B. Spinal cord injury was classified as grade C in 2 cases, grade D in 3 cases, and grade E in 17 cases according to Frankel scale. The time from injury to operation was 3-10 days (mean, 5.5 days). All patients underwent posterior reduction and fixation via the injured vertebra, transpedicular balloon reduction of the endplate and calcium sulfate cement (CSC) injection. The ratio of anterior vertebral height, the ratio of central vertebral height, the sagittal Cobb angle, the restoration of nervous function, and internal fixation failure were analyzed. ResultsPrimary healing of incision was obtained in the others except 2 cases of poor healing, which was cured after dressing change or debridement. All the patients were followed up 9-40 months (mean, 15 months). CSC leakage occurred in 2 cases. Absorption of CSC was observed at 8 weeks after operation with complete absorption time of 12-16 weeks (mean, 13.2 weeks). The mean fracture healing time was 18.5 weeks (range, 16-20 weeks). The ratio of anterior vertebral height, ratio of central vertebral height, and sagittal Cobb angle were significantly improved at 1 week and 3 months after operation and last follow-up when compared with preoperative values (P<0.01), but no significant difference was found among 3 time points after operation (P>0.01). There was no internal fixation failure or Cobb angle loss more than 10°. Frankel scale was improved with no deterioration of neurologic function injury. ConclusionBalloon vertebroplasty combined with short-segment pedicle screw instrumentation is simple and safe for the treatment of thoracolumbar burst fractures, and it can improve the quality of reduction, restore vertebral mechanical performance effectively, and prevent the loss of correction and internal fixation failure.

    Release date: Export PDF Favorites Scan
  • EXPERIMENTAL STUDY ON THE TREATMENT OF FEMUR HEAD NECROSIS WITH TRICALCIUM PHOSPHATE AND PLATELETRICH PLASMA

    Objective To study the mechanism of compound of calcium phosphate(TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis.Methods The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make themodel of femoral head necrosis.Twenty-four rabbits were randomly chosen as theexperimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4,8,12 weeks after operation. The specimens were examined with X-ray and histological study.Results At 2 weeks after operation,there was no significant difference in femoral headdensity between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8,12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed thatthere was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4,8,12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greaterthan those in control group.Bone histomorphometry showed that the volum of thetrabecular was larger in the experimental group (36.65%±7.22%,38.29%±4.28%,39.24%±3.42%) than that of control group(P<0.05). Conclusion TCP/PRP does not only provide osteoblasts scaffold, butalso promotes bone formation and the head repair. TCP/PRP is a good biomaterialfor the treatment of femur head necrosis.

    Release date:2016-09-01 09:29 Export PDF Favorites Scan
  • The protection of aminoguanidine,silymarin and anisodamine on growth and cytosolic free calcium changes of retinal capillary pericytes cultured in glycation products

    Objective To investigate the protective effect of aminoguanidine(AG),silymarin (Sil) and anisodamine (Ani) on retinal capillary pericytes cultured in glycosylation products. Methods MTT cololrimetric assay, [3H] thymidine incorporating and fluorescent indicat or fura-2 acetoxy-methyl ester (Fura-2AM) were used to study the influence of AG,Sil and Ani on the growth,DNA synthesis,and cytosolic free calcium ([Ca2 ]i)changes of pericytes cultured in the medium contained early glycation products (EGs) or advanced glycation end products (AGEs). Results Cultured in the medium contained EGs,the A value by MTT assayed and amount of [3H] thymidine incorporating in AG group and Sil group were obviously elevated than those of control group(Plt;0.01);but the [Ca2 ]iconcentration in both groups were decreased significantly comparing with control group(Plt;0.01 and 0.05).Under the condition of AEGs,only AG group was distinctly increased on the A value and amount of [3H] thymidine incorporatin g (Plt;0.01),and [Ca2 ]i concentration was markedly decreased (Plt;0.05) comparing with control group. Conclusion AG has the portective effect on pericytes against the proliferative inhibition and excessive elevation of [Ca2 ]i concentration in cytosol which are induced both by EGs or AGEs.Silymarin has the effect for those only by Egs-induced.Ani has no protective effect no pericytes nei ther cultured in medium with EGs nor with AGEs. (Chin J Ocul Fundus Dis, 2001,17:192-194)

    Release date:2016-09-02 06:03 Export PDF Favorites Scan
7 pages Previous 1 2 3 ... 7 Next

Format

Content