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101.
表皮生长因子与肿瘤坏死因子在胸腔积液中的表达 总被引:1,自引:0,他引:1
采用RIA法对58例良、恶性胸腔积液中EGF与TNF进行含量检测。结果显示22例良性胸水中EGF与TNF含量分别为2.03±0.35μg/L,1.63±0.54μg/L。36例恶性胸水中EGF与TNF含量分别为1.25±0.32μg/L,1.02±0.24μg/L。良性胸水组EGF与TNF浓度均明显高于恶性胸水组,两组间有显著性差异,(P<0.05)。结果表明EGF与TNF均参与了良、恶性胸腔积液的免疫病理生理过程。 相似文献
102.
行坏死肠管切除小肠单口造瘘术,延期行肠吻合术治疗重症小儿肠坏死10例。待病儿休克纠正后,再做Ⅱ期肠吻合术,此术式可及早缓解腹胀,减轻中毒症状,有利于休克纠正,未出现大量肠液丢失及切口裂开等并发症。 相似文献
103.
Oxidative stress, mitochondrial permeability transition, and cell death in Cu-exposed trout hepatocytes 总被引:11,自引:0,他引:11
We have previously shown that, in trout hepatocytes, exposure to a high dose of copper (Cu) leads to disruption of Ca(2+) homeostasis and elevated formation of reactive oxygen species (ROS), with the latter ultimately causing cell death. In the present study, we aimed at identifying, using a lower Cu concentration, the role of mitochondria in this scenario, the potential involvement of the mitochondrial permeability transition (MPT), and the mode of cell death induced by the metal. Incubation with 10 muM Cu resulted in a strong stimulation of ROS formation, and after 2 h of exposure a significant increase of both apoptotic and necrotic cells was seen. Co-incubation of Cu-treated hepatocytes with the iron-chelator deferoxamine significantly inhibited ROS production and completely prevented cell death. The origin of the radicals generated was at least partly mitochondrial, as visualized by confocal laser scanning microscopy. Furthermore, ROS production was diminished by inhibition of mitochondrial respiration, but since this also aggravated the elevation of intracellular Ca(2+) induced by Cu, it did not preserve cell viability. In a sub-population of cells, Cu induced a decrease of mitochondrial membrane potential and occurrence of the MPT. Cyclosporin A, which did not inhibit ROS formation, prevented the onset of the MPT and inhibited apoptotic, but not necrotic, cell death. Cu-induced apoptosis therefore appears to be dependent on induction of the MPT, but the prominent contribution of mitochondria to ROS generation also suggests an important role of mitochondria in necrotic cell death. 相似文献
104.
BACKGROUND: Identifying factors that can contribute to a better understanding of tumor progression in stage III colon cancer patients continues to be an important task. Necrotic changes in metastatic lymph nodes have not been previously analyzed in English literature. METHODS: The study included 48 consecutive colon and rectosigmoid cancer patients with stage III disease who underwent radical surgery. After reviewing the diagnostic slides, a pathologist developed a scale describing the extent of necrotic changes. Results were evaluated using Kaplan-Meier method and log-rank test. RESULTS: Thirty-four (70%) patients had necrotic changes in metastatic lymph nodes. Patients with necrotic changes in metastatic lymph nodes had more risk factors than patients without necrosis. The 5-year survival rate for patients with necrotic changes in metastatic lymph nodes was 85% and for patients without necrosis was 50% (P = 0.02). CONCLUSIONS: The survival of patients with necrotic changes in metastatic lymph nodes was higher (P = 0.02). These necrotic changes can help us to understand body-tumor relations. 相似文献
105.
Remes-Troche JM Duarte-Rojo A Morales G Robles-Díaz G 《World journal of gastroenterology : WJG》2005,11(44):7018-7023
AIM: To determine whether the hematocrit (Hct) at admission or at 24 h after admission was associated with severe acute pancreatitis (AP), organ failure (OF), and pancreatic necrosis. METHODS: A total of 336 consecutive patients with a first AP episode were studied. Etiology, Hct values at admission and at 24 h, development of severe AP according to Atlanta's criteria, pancreatic necrosis, OF and mortality were recorded. Hemoconcentration was defined as Hct level >44% for males and >40% for females. The t-test and X2 test were used to assess the association of hemoconcentration to the severity, necrosis and OF. Diagnostic accuracy was also determined. RESULTS: Biliary disease was the most frequent etiology (n = 148). Mean Hct levels at admission were 41±6% for females and 46±7% for males (P<0.01). Seventy-eight (23%) patients had severe AP, and OF developed in 45 (13%) patients. According to contrast-enhanced computed tomography scan, 36% (54/150) patients showed pancreatic necrosis. Hct levels were elevated in 58% (55/96) and 61% (33/54) patients with interstitial and necrotizing pancreatitis, respectively. Neither Hct levels at admission nor hemoconcentration at 24 h were associated with the severity, necrosis or OF. Sensitivity, specificity and positive predictive values for both determinations were very low; and negative predictive values were between 61% and 86%, being the highest value for OF. CONCLUSION: Hct is not a useful marker to predict a worse outcome in acute pancreatitis. In spite of the high negative predictive value of hemoconcentration, the prognosis gain is limited due to an already high incidence of mild disease. 相似文献
106.
Summary Chandipura virus was inoculated intraperitoneally into 9-day old mice. Rising viral titers were detected in blood, skeletal muscle and viscera, beginning 3 to 6 h post-inoculation. Significant quantities of virus were initially noted in the brain at 24 h, and titers in that region rose precipitously during the succeeding 72 h. Detectable clinical signs, including neurologic dysfunctions began 48 h post-inoculation. Death was common at 72 and 96 h. The most significant and consistently observed lesions were in the central nervous system and included necrosis of neurons and ependymal cells.Supported by U.S. Public Health Service Grants PHS-FR-05358-08 and PHS 2 PO 6 RR 00393. 相似文献
107.
Grossmayer GE Munoz LE Gaipl US Franz S Sheriff A Voll RE Kalden JR Herrmann M 《Modern rheumatology / the Japan Rheumatism Association》2005,15(6):383-390
Systemic lupus erythematosus (SLE) is a very heterogeneous systemic autoimmune disease, in which autoantibody synthesis against
nuclear constituents is the main immunological characteristic. These autoantibodies underwent affinity maturation and isotype
switching. Additionally, T-cell tolerance against nuclear autoantigens should be affected in these autoimmune patients. Nuclear
material derived from apoptotic and/or necrotic cells may serve as an important source of autoantigens. However, dead and
dying cells as well as cellular debris are rapidly removed from tissues by phagocytes without eliciting inflammation or immune
responses under healthy conditions. During apoptosis nuclear components are strongly modified through enzymatic reactions.
If these cells are not timely cleared, those autoantigens may be released, taken up, and presented by dendritic cells in tissues
or presented by follicular dendritic cells in lymph nodes to T and B cells, respectively. This could be a mechanism for breaking
the peripheral self-tolerance. In this article we focus on the deficient clearance of apoptotic cells in SLE patients and
its importance in development of this autoimmune disease.
G.E.G. and L.E.M. contributed equally to this work 相似文献
108.
Necrotic cells are generally considered to stimulate inflammation, whereas apoptotic cells should not. However, apoptotic cells have pro-inflammatory properties since they can activate complement. To what extent this activation compares to that by necrotic cells is not known. We compared complement activation by necrotic cells and apoptotic cells in plasma. Jurkat cells were made apoptotic or necrotic by incubation with etoposide or by heat shock, respectively. Cells incubated in recalcified plasma were tested for C3 and C4 fixation and fluid phase generation of complement activation products. Fixation of C3 and C4 to necrotic cells occurred mainly via the classical pathway, independent from the method of necrosis induction and the cell type. Depletion of IgM from plasma almost completely abrogated complement fixation by necrotic cells, which was restored by supplementation with purified IgM. Complement activation by late apoptotic cells was comparable to that by necrotic cells regarding the extent and dependence on IgM. Moreover, incubation of plasma with necrotic or late apoptotic cells led to the generation of comparable amounts of complement activation products. These results indicate that late apoptotic and necrotic cells employ similar complement activation mechanisms in the plasma environment. 相似文献
109.
Objective. From the knowledge of risk factors of epithelial ovarian cancer, we deduced a hypothesis that human seminal plasma (HSP) has a preventive role in the development of epithelial ovarian cancer. To examine whether HSP directly influences the growth of ovarian cancer, we have investigated the in vitro and in vivo effect of HSP on ovarian adenocarcinoma cell lines (SK-OV-3 and OVCAR-3) in comparison with its effects on normal ovarian surface epithelial cells (NOSE).Methods. Cell viability was determined by MTT assay. Cytotoxic effect was evaluated by flow cytometry analysis, by DNA laddering, and by morphological analysis. In vivo therapeutic effect of HSP was evaluated by the subcutaneous inoculation of SK-OV-3 cells in nude mice (BALB-c) model.Results. HSP at a final concentration of 1:50 induced a time- and dose-dependent inhibition of SK-OV-3 and OVCAR-3 growth, whereas NOSE was not affected. Flow cytometric analysis, DNA laddering, and morphological analysis indicated that HSP induced necrosis, rather than apoptosis, of both ovarian carcinoma cell lines. In in vivo experiment that used the nude mice (Balb-C) with tumor inoculation of SK-OV-3 cells, HSP induced necrosis of tumor with no detectable toxic effects on the major organs.Conclusion. These results show that HSP inhibits the growth and induces the necrosis of epithelial ovarian cancer cells and suggests that one or more components of HSP may provide a scientific basis for preventing epithelial ovarian cancer. 相似文献
110.
Prologation of c-Jun N-terminal kinase is associated with cell death induced by tumor necrosis factor alpha in human chondrocytes 总被引:1,自引:0,他引:1
The aim of this study was to elucidate the role of JNK signaling pathway involved in tumor necrosis factor-alpha (TNF-alpha)-induced death of chondrocytes. Primary chondrocyte cultures were obtained from human knee osteoarthritis cartilages. First passage chondrocytes were treated with TNF-alpha and various potentiators, and cell death was measured with MTT assay. C-Jun N terminal kinase (JNK) activation was investigated with the solid phase kinase assay. Expression of apoptosis-related molecule was assayed with Western blot. Chondrocytes were resistant to TNF-alpha-induced cell death. In contrast, pretreatment with actinomycin D, the phosphatase inhibitor vanadate or MAP kinase phosphatase-1 (MKP-1) inhibitor Ro318220 invariably led to chondrocyte death. While TNF-alpha alone stimulated a single, brief JNK activity, a second JNK peak was observed when the cells were pretreated with actinomycin D. When the cells were pretreated with vanadate or Ro318220, TNF-alpha-induced JNK activation was greatly prolonged, which was associated with the induction of cell death. The expression of Bcl-2 and Mcl-1 decreased significantly in conditions of cell death. In conclusions, our data suggest that chondrocyte death induced by TNF-alpha is associated with sustained JNK activation. This effect may be due to downregulation of TNF-alpha induced phosphatase that inactivates JNK and of Bcl-2 family proteins. 相似文献