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941.
Thuluvath PJ Maheshwari A Mehdi J Fairbanks KD Wu LL Gelrud LG Ryan MJ Anania FA Lobis IF Black M 《Gut》2004,53(1):130-135
BACKGROUND AND AIM: In this study, we compared the efficacy of triple therapy (interferon alfa, ribavirin, and amantadine) with standard therapy (interferon alfa and ribavirin) in treatment na?ve patients with chronic hepatitis C virus (HCV). METHODS: In this prospective, randomised, double blind, placebo controlled, multicentre study, 85 patients (amantadine group) received a three drug regimen of interferon alfa-2b 3 million units three times per week, ribavirin 1000-1200 mg daily in divided doses, and amantadine 100 mg twice daily, and 86 patients (placebo group) received interferon alfa-2b, ribavirin, and identical placebo. Treatment was discontinued at 24 weeks if patients had detectable HCV RNA by polymerase chain reaction (PCR). All patients were followed for 24 weeks after completion of treatment. The primary end point was undetectable HCV-RNA by PCR at 24 weeks (sustained viral clearance) after completion of treatment. RESULTS: At the end of treatment, HCV RNA clearance was seen in 32.9% of the amantadine group and 38.4% of the placebo group (p=0.3). Sustained virological response was seen in 24.7% of the amantadine group and in 27.9% of the placebo group by intention to treat analysis; response rate was 30.4% and 34.8%, respectively, in those who completed 24 weeks of treatment. Poor response was seen in both groups among cirrhotics, African-Americans, genotype 1, and those with a higher viral load. By multivariate analysis, genotype 1, high viral load, and low serum albumin were the only predictors of poor response. Addition of amantadine to the standard regimen did not result in any unexpected side effects. CONCLUSION: Response to triple therapy of interferon alfa, ribavirin, and amantadine was similar to standard therapy of interferon alfa and ribavirin. Our results suggest that amantadine has no role in the management of HCV. 相似文献
942.
943.
呼吸道感染患者肺炎衣原体感染的研究 总被引:8,自引:0,他引:8
呼吸道感染患者肺炎衣原体感染的研究施毅夏锡荣冯根宝胡兰萍康晓明肺炎衣原体是80年代后期新发现的呼吸道感染病原体[1]。我们采用微量免疫荧光试验(micro-IF)对呼吸道感染住院患者肺炎衣原体感染进行了研究。对象与方法(1)病例选择:1995年1~1... 相似文献
944.
Metabolic, membrane, and functional responses of human polymorphonuclear leukocytes to platelet-activating factor 总被引:13,自引:0,他引:13
The phospholipid mediator of anaphylaxis, platelet-activating factor (PAF) is chemotactic for polymorphonuclear leukocytes (PMN). We have examined this agent's effects on several other PMN functions. Human PMN were prepared from heparinized venous blood by Ficoll gradient. Metabolic burst was examined by measurement of O2 use and O2.- production in the presence or absence of PAF (10(-6)--10(-9) M). Unless cells were treated with cytochalasin-B (5 micrograms/ml), no significant respiratory burst was demonstrated. However, pretreatment with PAF (10(-7) M) enhanced approximately threefold the O2 utilization found when cells were subsequently stimulated with 10(-7) M FMLP. PAF also stimulated arachidonic acid metabolism in 14C-arachidonic acid- labeled PMN. Thin-layer chromatography analysis of chloroform-methanol extracts showed substances that comigrated with authentic 5- hydroxyeicosatetraenoic acid had a marked increase in radioactivity following PAF stimulation at 10(-7) M. PAF failed to stimulate release of granule enzymes, B-glucuronidase, lysozyme, or myeloperoxidase unless cytochalasin-B were added. PAF from 10(-6) M to 10(-10) M affected PMN surface responses. PMN labeled with the fluorescent dye, chlorotetracycline, showed decreased fluorescence upon addition of PAF, suggesting translocation of membrane-bound cations. Further, the rate of migration of PMN in an electric field was decreased following PAF exposure, a change consistent with reduced cell surface charge. PMN self-aggregation and adherence to endothelial cells were both influenced by PAF (10(-6) M--10(-9) M). Aggregation was markedly stimulated by the compound, and the percent PMN adhering to endothelial cell monolayers increased almost twofold in the presence of 10(-8) M PAF. Thus, PAF promotes a variety of PMN responses: enhances respiratory burst, stimulates arachidonic acid turnover, alters cell membrane cation content and surface charge, and promotes PMN self- aggregation as well as adherence to endothelial cells. 相似文献
945.
The current Indochinese resettlement program in the United States has resulted in an increase in the number of persons with hemoglobin E trait. American physicians should be aware of the hematologic expressions of this innocuous condition. The hematologic manifestations of 21 persons with hemoglobin E trait were evaluated. The subjects were of Tai-dam, Vietnamese, Chinese, Laotian, and European origin. These studies showed uniform hematologic manifestations in hemoglobin E trait, characterized by slight microcytosis, by morphologic features resembling those of thalassemia minor, and often by increased erythrocyte count. Hemoglobin instability also was confirmed. 相似文献
946.
E-selectin-dependent neutrophil adhesion to Rickettsia rickettsii- infected endothelial cells 总被引:6,自引:0,他引:6
Increased neutrophil or HL60 cell adhesion to Rickettsia rickettsii- infected endothelial cells (ECs) was observed at 6 to 8 hours after the initiation of infection, diminishing by 24 hours. Similar increases were observed using formaldehyde-fixed neutrophils. Cellular association and likely the intracellular presence of rickettsiae was required for enhanced neutrophil adhesion, because culture medium conditioned by infected cells or rickettsiae rendered noninfective by pretreatment with tetracycline were ineffective at inducing neutrophil adhesion. Increases in neutrophil adhesion caused by infection were blocked by pretreatment of ECs with cycloheximide, suggesting the involvement of new protein synthesis in the cells' response. Flow cytometric analysis of infected cells showed increases in cell surface expression of E-selectin compared with uninfected control cells. Furthermore, incubation of 6- to 8-hour infected cells with a blocking monoclonal antibody against E-selectin (BB11) inhibited neutrophil adhesion an average of 61%. These results suggest the involvement of E- selectin in neutrophil adhesion to infected ECs occurring early in the course of the infection process. EC-initiated recruitment of neutrophil adhesion during rickettsiae infection could contribute to the pathologic changes associated with Rocky Mountain Spotted Fever. 相似文献
947.
Unequal crossing-over: a common basis of single alpha-globin genes in Asians and American blacks with hemoglobin-H disease 总被引:5,自引:0,他引:5
Phillips JA d; Vik TA; Scott AF; Young KE; Kazazian HH Jr; Smith KD; Fairbanks VF; Koenig HM 《Blood》1980,55(6):1066-1069
The alpha-globin genes of five black Americans, two Chinese, and five Filipinos with HbH disease (an alpha-thalassemia state in which there is a single functional alpha gene) were analyzed by restriction endonuclease techniques. All subjects were found to have one chromosome 16, lacking both alpha genes, and another containing a single alpha gene (--/-alpha). Restriction endonuclease patterns of the DNA obtained from all 12 subjects were identical and compatible with unequal crossing-over as the mechanism of origin of the single alpha gene in these individuals. 相似文献
948.
949.
Rodent nutritional model of steatohepatitis: Effects of endotoxin (lipopolysaccharide) and tumor necrosis factor alpha deficiency 总被引:2,自引:0,他引:2
RICHARD KIRSCH VIVIAN CLARKSON ROBERT C VERDONK ADRIAN D MARAIS ENID G SHEPHARD BERNARD RYFFEL PAULINE DE LA M HALL 《Journal of gastroenterology and hepatology》2006,21(1):174-182
Background and Aims: Intestinal endotoxin (lipopolysaccharide) is thought to contribute to liver injury in both alcoholic and nonalcoholic steatohepatitis (NASH). Tumor necrosis factor alpha (TNFα) is an important mediator of this process and is considered central to the inflammatory response in NASH. This study aimed to investigate the effects of lipopolysaccharide on liver injury in the methionine choline deficient (MCD) nutritional model of NASH, and to determine if TNFα is required for the development of steatohepatitis in this model. Method: Male C57/BL6 mice received a MCD diet for 4 weeks, whilst a control group received an identical diet supplemented with 0.2% choline bitartrate and 0.3% methionine. At 4 weeks, mice received either an intraperitoneal injection of lipopolysaccharide (0.5 µg/g body mass) or sterile saline, and were killed 24 h thereafter. In a separate study, TNFα knockout and wild type C57BL/6 mice received either MCD or control diets for 4 weeks. Serum transaminase levels, liver histology (steatosis, inflammation and apoptosis), hepatic triglyceride concentration and hepatic lipid peroxidation products (conjugated dienes, lipid hydroperoxides and thiobarbituric reactive substances, free and total) were evaluated. Results: Intraperitoneal administration of lipopolysaccharide augmented serum alanine aminotransferase (ALT) levels (P < 0.02), hepatic inflammation (P < 0.025), apoptosis (P < 0.01) and free thiobarbituric acid reactive substances (P < 0.025) in MCD mice. TNFα knockout mice fed the MCD diet developed steatohepatitis with histological and biochemical changes similar to those seen in wild type counterparts. Conclusions: Lipopolysaccharide augments liver injury in MCD mice, and TNFα is not required for the development of steatohepatitis in MCD mice. 相似文献
950.
Disease relapse after allogeneic bone marrow transplantation (BMT) is a major cause of treatment failure and is thought to evolve from clinically occult residual disease in the recipient. However, the demonstration of minimal residual disease (MRD) in individual patients is of uncertain prognostic significance because the detection of residual disease has not consistently correlated with subsequent relapse. Moreover, the optimal therapeutic approach in patients with MRD after allogeneic BMT is unknown. The study of these issues has been hindered by the lack of clinically relevant animal models. In this report, we characterize a novel murine model for the study of MRD after allogeneic BMT. This model was designed to simulate high-risk BMT in humans in which patients receive transplants in relapse and disease recurrence in the major cause of treatment failure. The H-2-compatible, mixed lymphocyte culture nonreactive murine strains, AKR (H-2k) and CBA (H-2k), were chosen to parallel marrow transplants from HLA-matched siblings, which represent the majority of allo-transplants in humans. Male AKR leukemia cells were used in female donor/host chimeras permitting the Y chromosome to serve as a leukemia-specific marker for MRD. Detection of residual male leukemia cells in the peripheral blood of the primary host was facilitated by use of the polymerase chain reaction (PCR) and sequence-specific oligonucleotide probe hybridization (SSOPH). Use of PCR/SSOPH was highly predictive of clinical outcome (relapse or cure) in animals receiving transplants (P < .00002) and detected disease recurrence earlier than comparative flow cytometric analysis studies. This murine model will be useful in evaluating the efficacy of therapeutic strategies aimed at reducing disease relapse posttransplant and can be adapted to other transplant murine tumor systems for the study of MRD. 相似文献