Objective To investigate the protective effects of antitumor necrosis factor-α antibody (TNF-αAb) on lung injury after cardiopulmonary bypass (CPB) and their mechanisms. Methods Forty healthy New Zealand white rabbits,weighting 2.0-2.5 kg,male or female,were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ,the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ,the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ,the rabbits received CPB only. In group Ⅳ,the rabbits only received sham surgery. Neutrophils count,TNF-α and malondialdehyde (MDA) concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content,TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ,after CPB,the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count,TNF-α and MDA(P<0.05),higherTNF-α mRNA expression,apoptosis index and water content of the lung tissues (P<0.05),and significantly lower oxyg-enation index (P<0.05) as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ,after CPB,the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α (5 minutes after aortic declamping,220.43±16.44 pg/ml vs.185.27±11.78 pg/ml,P<0.05;249.99±14.09 pg/ml vs.185.27±11.78 pg/ml,P<0.05),significantly higher apoptosis index (at the time of CPB termination,60.7‰±13.09‰ vs. 37.9‰±7.78‰,P<0.05;59.6‰±7.74‰ vs. 37.9‰±7.78‰,P<0.05),significantly higher blood levels of neutrophils count and MDA (P<0.05),significantly higher TNF-α mRNA expression and water content of the lung tissues (P<0.05),and significantly loweroxygenation index (P<0.05) as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ,rabbits in group Ⅲ had significantly higher above parameters (P<0.05) but lower oxygenation index (P<0.05) only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.
Objective To evaluate the phenomena of apoptosis and its relevant mechanism during ischemia-reperfusion period. Methods The published papers to explore the apoptotic phenomena and its mechanism in organs or tissues which experienced ischemia-reperfusion injury were reviewed. Results Apoptosis was common in ischemia-reperfusioned organ or tissue. The severity of apoptosis was influenced by many factors such as ischemia, hypoxia, oxygen free radials, intracellular free calcium ion overloading, various cytokines, et al; and also was regulated by bcl-2 family, caspase family and NF-κB,et al. Conclusion Apoptosis is a common phenomenum in ischemiareperfusioned organ or tissue which is affected and regulated by various factors.
Objective To further investigate pathologic mechanism of retinal phototrauma. Methods Twenty Wistar rats were divided into control and experimental groups.Their eyes were extracted in 12,24 and 36 hours after light exposure.HE stained retina samples were examined and TDT-mediated dUTP nick end labelling(TUNEL)method was employed to distinguish apoptotic cells. Results After 12-hour light exposure,slight vesiculation was observed in the rod outer segment of the retinas.After 24-hour light exposure,the outer nuclear layer showed predominant fractured and condensed nuclei and fragmented DNA.After 36-hour light exposure,the rod outer and inner segments were lysed and most of the nuclei in the outer nuclear layer were disappeared. Conclusions Apoptosis of photoreceptor cell is one of the important mechanisms which cause experimental retinal photoinjury of rats. (Chin J Ocul Fundus Dis, 1999, 15: 167-169)
【Abstract】Objective To investigate the apoptosis induced by TGF-β1 in human hepatic carcinoma cell lines and its relationship with p53 gene and Smad. Methods Three human hepatic carcinoma cell lines which involving in various status of the p53 gene were used in this study. TGF-β1-induced apoptosis in hepatic carcinoma cell lines was measured by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. To study the mechanism of TGF-β1-induced apoptosis, these cell lines were transfected with a TGF-β1-inducible luciferase reporter plasmid containing Smad 4 binding elements (SBE) and luciferase gene using Lipofectamine 2000, then treated with TGF-β1, relative luciferase activity was assayed. Results Of three cell lines studied with TUNEL assay, TGF-β1 induced apoptosis was observed in HepG2 cells (wild type p53). Huh-7 (mutant p53) and Hep3B (deleted p53) cell lines showed less apoptosis. Luciferase activity assay indicated that the response to TGF-β1 induction in HepG2 cells was increased dramatically but was not significant in Huh-7 and Hep3B cell lines. Conclusion HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh7 cell lines. Smad 4 is a central mediator of the TGF-β1 signal transduction pathway.
ObjectiveTo explore the new gene therapy method for tumor, the recombinant Caspase3 gene (rcaspase3) eukaryotic expression plasmid was constructed by molecular biologic method. MethodsThe eukaryotic expression plasmid pcDNA3.1(+)/rCaspase3 was constructed by rearrangement of the large subunit and small subunit of Caspase3 and it was transfected into pancreatic carcinoma cells(PCⅡ). After being transfected, the expression of rCaspase3 mRNA in pancreatic carcinoma cells was detected by RTPCR and it’s apoptotic activity was detected by FCM. ResultsThe sequence of rCaspase3 showed that the recombinant molecules (rCaspase3) now had its’ small subunit preceding its’ large subunit. After pancreatic carcinoma cells being transfected with the pcDNA3.1(+)/rCaspase3 by liposomes, a 894 bp strap was observed by RTPCR. No strap was found in control groups. A transparent hypodiploid karyotype peak was found by FCM.ConclusionThe plasmid of pcDNA3.1(+)/rCaspase3 has been constructed successfully. rCaspase3 has apoptotic activity and can be used as target gene in gene therapy for pancreatic carcinoma.
Objective To investigate the relationship between the expression of apoptosis-related gene Fas and recovery of neurological function after surgical decompression at different time points in acute spinal cord injury (SCI) rat model by cerclage. Methods A total of 100 13-week-old male Sprague Dawley rats (weighing, 255-376 g) were randomly divided into 4 groups (n=25). The rats only received laminectomy in group A as control; the rats were made the acute SCI models by cerclage in groups B, C, and D. The spinal cord decompression was performed in group B at 8 hours and in group C at 72 hours, no spinal cord decompression in group D. At 1, 3, 7, 14, and 21 days, Basso-Beattie-Bresnahan (BBB) score and inclined plane test were used to evaluate the recovery of neurological function; the neuronal apoptosis level of spinal cord was examined by TUNEL staining; HE staining and immunohistochemical staining were applied to analyze the expressions of Fas. Results The BBB score and inclined plane test score in group A were significantly better than those in groups B, C, and D at different time points (P lt; 0.05); group B was significantly better than groups C and D, and group C than group D at 3, 7, 14, and 21 days (P lt; 0.05). In group A, no bleeding, edema, or necrosis was found. The edema, hemorrhage, and neuron death were observed in spinal cord tissue of groups B, C, and D at 1 day after operation, especially in group D. The degree of cell degeneration in group B was lighter than that in groups C and D at 3 and 7 days after operation; few glial cells and fibroblast proliferation were found at damaged zone in group B at 14 and 21 days, but necrosis and cystic cavity in groups C and D. Fas and TUNEL expression was little in group A at different time points. Fas and TUNEL were expressed in groups B, C, and D; the expressions of Fas and TUNEL reached the maximum at 3 days, and then gradually decreased at 7 and 21 days. The number of positive cells was highest in group D, and the number of positive cells in group B was significantly less than that in groups C and D (P lt; 0.05). Conclusion Early decompression of SCI is beneficial to recovering the neurological function. The Fas signal pathway may play an important role in the apoptosis of neuron and glial cells after SCI.
目的 探討HIF-1α和BAK蛋白在胃癌中的表達情況,以及二者在胃癌中的相互關系及作用。方法 應用免疫組化SABC染色法檢測80例胃癌組織和20例正常胃組織中的HIF-1α和BAK蛋白的表達情況。結果 胃癌中HIF-lα和BAK蛋白的表達陽性率分別為56.3%(45/80)和67.5%(54/80),而在胃正常組織中分別為5.0%(1/20)和20.0%(4/20),二者在胃癌中的表達顯著高于胃正常組織,其差異有統計學意義(P<0.05)。HIF-1α蛋白表達與胃癌組織的浸潤范圍、分化程度及淋巴結轉移有關(P<0.05),與臨床分期、年齡及性別無關(P>0.05);BAK蛋白表達與胃癌浸潤及分化程度相關(P<0.05),與淋巴結轉移、臨床分期、年齡及性別無關(P>0.05)。胃癌組織中HIF-1α與BAK蛋白的陽性表達之間呈正相關(列聯系數r=0.056,P<0.05)。結論 HIF-1α與BAK蛋白在胃癌的臨床分期及浸潤轉移中存在關系,這對于研究胃癌的發生和發展,以及對于探索以二者為靶點的抗腫瘤治療有重要意義。
ObjectiveTo establish the co-culture model of mice's early embryo and tumor cells in Vitro to observe the embryonic development and biologic behavior of tumor cells in the same microenvironment and discuss their interaction. MethodsWe acquired 2-cell embryos from mice, and then co-cultured them with tumor cell lines of mice in Vitro. We observed the development of embryos in Vitro and the rates of 4-cell embryos, morula and blastocyst formation. The transwell chamber was used for culture. Methylthiazolyldiphenyl-tetrazolium method was used to test the proliferative activity of tumor cells, while the flow cytometry was used to test its apoptosis. The interaction of co-cultured embryos and tumor cells was analyzed by propidium iodide staining and immunohistochemical technique. ResultsThe co-cultured 2-cell embryos could continue surviving and developing. The rates of 4-cell embryos, morula and blastocyst formation increased significantly in the co-cultured group (P<0.05). There was no significant difference in the proliferative activity and apoptosis of tumor cells between the co-cultured group and the control group (P>0.05). Tumor-free ring formed between the trophoblast and tumor cells. We could observe tumor cells stacked around the tumor-free ring. However, no difference in expression of proliferating cell nuclear antigen and B-cell lymphoma leukemia-2 was observed in tumor cells stacking around the tumor-free ring compared with those elsewhere. ConclusionThe development of 2-cell embryos is enhanced in the co-culture model. The proliferative activity and apoptosis of tumor cells are not affected in this model. A tumor-free ring can form between trophoblast and tumor cells. However, the proliferative activity of tumor cells is not affected by this ring.
Objective To study the effect of water soluble chitosan (WSC) on the apoptosis of peritoneal macrophage induced by lipopolysaccharides (LPS), and discuss the mechanism. Methods Peritoneal macrophages were divided to three groups: phosphate buffered saline (PBS) group, LPS group and LPS plus WSC group. At hour 24, apoptosis cell and active caspase-3 were detected by flow cytometry; nitric oxide (NO) was determined with Griess reagent. Results There were more apoptosis cells in the LPS group than the PBS group. The percentage of apoptosis cells was significantly decreased in the LPS plus WSC group than the LPS group. The expression of active caspase-3 and the secretion of NO were also inhibited by WSC after LPS intervention. Conclusion WSC inhibits apoptosis of peritoneal macrophage induced by LPS.