钙及其拮抗剂对苹果果肉质膜透性的调节作用

采用培养果肉圆片的方法,研究了Ca2+及其拮抗剂对苹果果肉质膜透性的调节作用。结果表明,CaCl2(1、10mmol/L)降低果肉膜透性和溶质外渗速率(Js);细胞膜Ca2+通道阻塞剂Verapamil(100μmol/L)的影响不显著;细胞外Ca2+螯合剂EGTA(5mmol/L)、CaM的拮抗剂CPZ、TFP(100μmol/L)明显提高果肉膜透性和细胞溶质外渗速率。培养24h时,CaCl2能明显维持较高的SOD活性和ACC向乙烯的转化能力,EGTA、Verapamail、CPZ和TFP的作用相反。这些说明Ca2+对果肉细胞膜具有保护作用,而减少细胞外Ca2+和抑制细胞内Ca2+-CaM功能对果肉细胞膜具有伤害作用。     

Model establishment and biological behaviour observation of mouse blastocyst co-cultured with hepatocarcinoma cell lines with differently invasive and metastatic potential in vitro

AIM: To explore interaction and biological behaviour changes of two kinds of cells-blastocysts and hepatocarcinoma cells in the same microenvironment. METHODS:The models of mouse blastocysts co-cultured with human hepatocarcinoma cell lines were established, then biological behaviours and mutual effects of the two kinds of cells in co-culture system were observed. RESULTS: Compared with control group, hepatocarcinoma cells with differently invasive and metastatic potential significantly enhanced the rates of blastocyst hatchment , attachment and outgrowth(P＜0.05). There was no significant difference in those among hepatocarcinoma cells co-cultured groups (P＞0.05). The blastocyst hatched and attached to hepatocarcinoma cells with differently invasive and metastatic potential. Then, differential trophoblasts invaded hepatocarcinoma cells. The clear-cut interfaces were gradually formed between both sides. Hepatocarcinoma cells on interface showed changes of growth direction and cell shapes and did not invade blastocysts. CONCLUSIONS: Hepatocarcinoma cells promoted blastocyst development. Blastocysts implanted and invaded hepatocarcinoma cells with differently invasive and metastatic potential in vitro, which indicate that blastocyst implantation in vitro does not relate with the kinds and differential level of interactional cells and the low selectivity maybe relate with high adaptability of early life.     

Analysis of blood biochemistry and arterial blood gas of systemic inflammatory response syndrome in the early time after trauma

AIM: To explore the variation of blood biochemistry and arterial blood gas of patients with systemic inflammatory response syndrome (SIRS) in the early time after trauma and improve the diagnosis and first aid. METHODS: Eighty-eight patients with trauma from August 2003 to February 2004 were divided into two groups by their AIS-ISS90 score. The data of temperature, pulse, respiratory rate, white blood cell counts, Hb, blood glucose and arterial blood gas (PaO₂, PaCO₂, HCO₃^-, AG) were collected and compared with each group by statistic methods. RESULTS: Of the 88 patients, 49 underwent SIRS, 12 in light trauma group (ISS≥16) and 37 in severe trauma group (ISS<16). Compared with light trauma group, the data of pulse, respiratory rate, white blood cell counts, blood glucose, AG and rate of SIRS of severe trauma group were higher, PaO₂ and HCO₃^- were lower and the cases of PaCO₂>45 mmHg or <35 mmHg were more (P<0.01). The data of temperature and Hb had not significant difference between two groups (P>0.05). 13 patients had MODS in severe trauma group and 2 died while none had MODS or died in light trauma group. CONCLUSION: Application of AIS-ISS90 and SIRS-related blood biochemistry and arterial blood gas is beneficial for the diagnosis and treatment of patients in the early time after trauma.     

Effect of insulin on the secretion of VEGF and its receptor in serum-free cultured bovine thoracic aortic endothelial cells

AIM: This study was designed to investigate the secretion of VEGF and its receptor (flt-1 or flk-1/KDR) protein by cultured bovine thoracic aortic endothelial cells treated with various insulin concentrations. METHODS: Endothelial cells was isolated from bovine thoracic aorta, and cultured in serum-free medium, then incubated with different insulin concentrations (30 mU/L, 300 mU/L, 3 000 mU/L). The level of VEGF and its receptor (flt-1 or flk-1/KDR) protein were detected by immunohistochemical staining. RESULTS: As compared with no insulin group, the expression of VEGF protein in low insulin concentration (30 mU/L and 300 mU/L) groups were significantly increased (P＜0.01). The expression of VEGF protein in high insulin concentration (3 000 mU/L) group was significantly decreased (P＜0.05). Howerer, no difference of the expression of VEGF receptor (flt-1 or flk-1/KDR) protein among all groups (P＞0.05) was observed. CONCLUSION: Low concentration insulin up-regulates the VEGF protein expression while high concentration insulin down-regulates the VEGF protein expression in bovine thoracic aortic endothelial cells, but insulin had no directly effect on the VEGF receptor (flt-1 or flk-1/KDR) protein expression in bovine thoracic aortic endothelial cells.     

Effect of EGFP gene transfection on the cell cycle distribution of primary cultured human chondrocytes

AIM: To investigate the effect of enhanced green fluorescence protein (EGFP) gene transfection on the cell cycle distribution of primary cultured human chondrocytes in order to establish a tracking method of cultured human nasoseptal chondrocytes. METHODS: pEGFP-N1 plasmid was amplified in E.coli, and purified by high purity kit. Primary cultured human chondrocytes,which were initially obtained from the nasoseptal cartilage, were cultured in vitro and transferred with pEGFP-N1 by means of electroporation with Amaxa nucleofector device. Transfering process and transient expression were evaluated by laser scanning confocal microscope (LSCM), the transfer efficiency and the cell cycle distribution were evaluated by flow cytometry. RESULTS: There was significant expression of EGFP at 24 h after transferring. The transfection efficiency of pEGFP-N1 into primary cultured human chondrocytes reached 35.37％ at 48 h. It didn't affect the process of cell adherance and had no effect on the cell cycle distribution. CONCLUSION: Primary cultured human chondrocytes, which were transfected with pEGFP, are alive in vitro, and the transferring process doesn't affect the cell cycle distribution. These results suggest that pEGFP-N1 is an ideal transient expression vector for primary cultured human chondrocytes and it might be a well tracer in construction tissue engineered cartilage.     

Osmolarity,cell volume and proliferation in nasopharyngeal carcinoma cells

AIM: To investigate the relationship between osmolarity, cell volume and cell proliferation in nasopharyngeal carcinoma cells. METHODS: MTT method was applied to detect the proliferation ability of the poorly-differentiated nasopharyngeal carcinoma cell (CNE-2Z) under various osmolarity conditions. The flow cytometry was used to analyse cell cycle distribution. Cell volume was obtained by the image analysis of living cells and cell viability was determined by the trypan blue assay. RESULTS: Cultivation of cells under the hypertonic conditions of 370 and 440 mOsmol/L increased cell volume by 8.7% and 27.8% and facilitated cell proliferation by 22.2% and 33.9%, respectively. However, hypotonic incubation of cells with osmolarity of 160 and 230 mOsmol/L decreased cell volume by 12.8% and 4.1% and inhibited cell proliferation by 34.0% and 15.6%, respectively. Cell volume was positively correlated with cell proliferation rate. Long-term cultivation of cells under anisotonic conditions did not significantly alter cell cycle distribution, but hypotonic cultivation decreased cell viability. CONCLUSION: Proliferation of nasopharyngeal carcinoma cells was closely correlated with the osmolarity of culture medium and cell volume. Hypotonic cultivation may inhibit cell proliferation by decreasing cell volume to facilitate cell death mechanisms.     

Effects of component of some Chinese herbs on proliferation of human umbilical vein endothelial cells in vitro

AIM: To observe the effects of some component of Chinese herbs for external use on proliferation of human umbilical vein endothelial cells (HUVEC) and investigate the mechanism of promoting tissue repair. METHODS: The method of MTT was used to examine the effects of Rg1, Rh1, perlolyrine, cinnamyl aldehyde, muscone, astragaluspolysaccharin (APS), velver antler polypeptide (VAP) and soluble extract of boswellia carterii birdw (BCB) on proliferation of HUVEC. RESULTS: APS did not promote proliferation of HUVEC at 9.75 mg/L-2.5 g/L; Rh1 promoted proliferation of HUVEC at 1.94 mg/L-0.5 g/L (P<0.05 or P＜0.01), and Rg1 inhibited proliferation of HUVEC at 31 mg/L (P<0.05); VAP promoted proliferation of HUVEC at 1 mg/L-0.5 g/L with optimal dose of 10 mg/L (P<0.01), Cinnamyl aldehyde promoted proliferation of HUVEC at 2 g/L(P＜0. 05); Muscone and soluble extract of BCB inhibited proliferation of HUVEC at 1 g/L, 0.5-2.5 kg/L(P＜0. 01), respectively; Perlolyrine inhibited proliferation of HUVEC at 0.125 g/L-0.5 g/L(P＜0. 01). CONCLUSION: The external herbs for supplementing Qi and warming Yang can promote HUVEC proliferation and improve angiogenesis during tissue repair. The external herbs for promoting blood circulation and accelerating capillary movement may have influence upon other stages of tissue repair.     

Chloride channels of platelets

Chloride channels distribute widely in the body, and participate in many physiological actions and regulatory processes. Based on their physiological roles and molecular structures, six kinds of chloride channels have been identified: (1) The chloride channels family; (2) Cystic fibrosis transmembrane conductance regulator; (3) Swelling-activated chloride channels; (4) Calcium-activated chloride channels; (5) The p64 (CLIC) gene family; (6) γ-aminobutyric acid and glycine receptors. The chloride channels do exist in platelets, and their appearances are dependent on the presence of intracellular calcium. Blocking agents of chloride channels inhibit the thrombin-activated platelet aggregation and the elevation of the intracellular calcium concentration in a dose-dependent manner. It is suggested that chloride channels play a role in the activation of platelets. In addition, chloride channels act on both the cell volume regulation and the intracellular pH regulation in platelets.     

Recent advances in molecular mechanisms of oncosis

Oncosis is another form of cell death, which is different from apoptosis. The review will discuss the recent advances of oncosis on pathological morphology, nuclear biochemical changes and molecular mechanisms.     

二丁酰环腺苷酸的合成与性质研究

以ATP为原料采用化学方法合成了dbcAMP及其钠盐 ,并对其理化性质和吸收特性进行了研究。经质谱分析 ,其结构为C18H2 3 N5O8PNa ,分子量为 4 90 .0 ;经紫外光谱测定其含量为 96 .0 % ,产品的得率为 85 .6 %。dbcAMP钠盐为白色粉末 ,可溶于水与乙醇 ,对热和酸碱比较稳定。经饲料添加和皮下注射dbcAMP检测其经消化道和皮下吸收的性能。通过测定饲喂和皮下注射dbcAMP后 0 .5h、1～ 96h不同时间内血液dbcAMP的浓度表明 ,饲料添加在 3h内达到最大浓度 84 .75pmol/mL ,皮下注射在 2h内达到最大浓度 92 .96pmol/mL ,之后血液中dbcAMP的浓度逐渐下降 ,在 96h达到较低水平。