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101.
Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers 总被引:2,自引:0,他引:2
Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention. 相似文献
102.
Involvement of platelet-activating factor and tumour necrosis factor in the pathogenesis of joint inflammation in rabbits.
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P Zarco C Maestre G Herrero-Beaumont E Gonzlez R Garcia-Hoyo F J Navarro P Braquet J Egido 《Clinical and experimental immunology》1992,88(2):318-323
We have studied the participation of platelet-activating factor (PAF) in antigen-induced arthritis in rabbits, as well as the possible co-operation between PAF and tumour necrosis factor (TNF) in their ability to induce joint inflammation when injected into the knees of healthy rabbits. The administration of two structurally different PAF receptor antagonists, BN52021 and Alprazolam, from 4 h before the intra-articular injection of ovalbumin in preimmunized rabbits, induced an important reduction in the synovial fluid volume, in the amount of cells infiltrating the articular cavity and the synovial membrane, as well as in the prostaglandin E2 (PGE2) concentration. Furthermore, proteoglycans of the articular cartilage, which were found diminished in animals with non-treated arthritis, were well preserved in rabbits treated with PAF antagonists. All the synovial fluids from joints with arthritis had detectable amounts of PAF. The injection of either TNF or PAF into the joints of normal rabbits induced a mild inflammation. When TNF was administered 1 h before PAF, a synergistic response was noted in the synovial fluid volume, in the accumulation of leucocytes, and in the amount of PGE2. The administration of BN50726, a hetrazepine with a potent PAF-receptor antagonist effect, induced a diminution in those parameters. Our results suggest that PAF may be an early and important mediator of joint damage, and that TNF can amplify the inflammatory response induced by PAF. PAF receptor antagonists could play some role in the treatment of inflammatory joint diseases. 相似文献
103.
104.
Splanchnic ischaemia and its role in multiple organ failure 总被引:3,自引:0,他引:3
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed. 相似文献
105.
Lyme arthritis, the most common manifestation of late Lyme disease, has been associated with the presence of Borellia burgdorferi in the joint. However, it is still unclear whether the pathogen itself is able to elicit such a sustained inflammatory response, or whether an aberrant immunological reaction of the host is the main driving force. Borrelia antigens, including lipoproteins, flagellin and DNA, are ligands of Toll-like receptors, and can thus elicit a strong stimulation of host cells, such as neutrophils, mononuclear cells and resident tissue cells. Understanding the molecular basis of the signalling events caused by Borrelia lipoproteins will lead to a greater understanding of inflammation in Lyme arthritis and, hopefully, new treatment strategies for chronic antibiotic-resistant disease. 相似文献
106.
中西医结合治疗慢性盆腔炎100例疗效观察 总被引:2,自引:1,他引:1
目的:采用中西医结合治疗慢性盆腔炎,减少复发,提高治愈率。方法:对我院门诊患者100例采用胎盘组织液肌注,金钢藤胶囊口服,并用我院自制中药妇炎肠疗液灌肠。结果:临床显效40例,有效56例,无效4例,总有效率96%。结论:中西医结合治疗慢性盆腔炎疗效满意,是目前治疗慢性盆腔炎的最好方法。 相似文献
107.
Treatment with combined oral contraceptives induces a rise in serum C-reactive protein in the absence of a general inflammatory response 总被引:2,自引:0,他引:2
M. VAN ROOIJEN L. O. HANSSON† J. FROSTEGÅRD‡ A. SILVEIRA§ A. HAMSTEN§ K. BREMME 《Journal of thrombosis and haemostasis》2006,4(1):77-82
BACKGROUND: The role of inflammation in the pathogenesis of cardiovascular disease is well established. C-reactive protein (CRP) is the strongest independent predictor of myocardial infarction and stroke in women. Recent studies have indicated that CRP levels are raised during use of combined oral contraceptives (COCs). OBJECTIVES: The aim of the study was to investigate the effect of COCs on serum CRP levels and to indicate the underlying mechanisms of an expected increase. METHOD: In a prospective randomized cross over-study 35 women used two different preparations of COC, one second and one third generation. Serum levels of CRP, serum amyloid A (SAA), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), antibodies against oxidized LDL, insulin and insulin-like growth factor-I (IGF-I) along with insulin-like growth factor binding protein-1 (IGFBP-1) and IGFBP-3 were analyzed before and during the two treatments. E-selectin, von Willebrand factor and factor VIII concentrations in plasma were also measured. RESULTS: A rise in serum CRP was observed during both treatments; the median level increased from 0.45 mg L(-1) at baseline to 1.48 mg L(-1) with second generation and to 2.02 mg L(-1) with third generation COC. The serum levels of SAA increased slightly during treatment with the third generation COC. IL-6 and TNFalpha were unaffected by treatment. Both preparations lowered IGF-I and raised IGFBP-1 and IGFBP-3 concentrations. CONCLUSION: The raised serum CRP concentration during treatment with COCs appears to be related to a direct effect on hepatocyte CRP synthesis and does not reflect IL-6 mediated inflammation, endothelial activation or induction of insulin resistance. 相似文献
108.
Summary: The origins of human mesial temporal lobe epilepsy and hippocampal sclerosis are still not well understood. Hippocampal sclerosis and temporal lobe epileptogenesis involve a series of pathologies including hippocampal neuronal loss and gliosis, axonal reorganization, and maybe hippocampal neoneurogenesis. However, the causality of these events is unclear as well as their relation to the factors that may precipitate epileptogenesis. Significant differences between temporal lobe epileptogenesis in the adult and immature brain may require differential approaches. Hereditary factors also may participate in some cases of hippocampal sclerosis. The key point is to identify the significance of these age-dependent changes and to design preventive treatments. Novel strategies for the prevention and treatment of mesial temporal lobe epilepsy and hippocampal sclerosis may include rational use of neuroprotective agents, hormonotherapy, immunizations, and immunotherapy. 相似文献
109.
Claudio Franceschi MD 《Nutrition reviews》2007,65(S3):S173-S176
Widespread aging at the population level is a recent phenomenon that emerged in affluent societies. Inflammation is necessary to cope with damaging agents and is crucial for survival, particularly to cope with acute inflammation during our reproductive years. But chronic exposure to a variety of antigens, especially to some viruses such as cytomegalovirus, for a period much longer than that predicted by evolution, induces a chronic low-grade inflammatory status that contributes to age-associated morbidity and mortality. This condition carries the proposed name "inflammaging". Centenarians are unique in that, despite high levels of pro-inflammatory markers, they also exhibit anti-inflammatory markers that may delay disease onset. The key to successful aging and longevity is to decrease chronic inflammation without compromising an acute response when exposed to pathogens. 相似文献
110.
外科系统分离菌对抗生素耐药性的监测 总被引:4,自引:0,他引:4
研究外科感染的病原菌及其对抗生素的耐药性,以指导临床用药。方法:采用Vitek-AmsSystem和K-B法,对外科临床标本进行细菌培养并菌株对18种的耐药性。 相似文献