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1.
To investigate the mechanism of the long-lasting efficacy of chimeric monoclonal anti-TNF antibody (cA2) therapy for rheumatoid arthritis (RA), eight patients with refractory RA were treated with a single infusion of cA2 and the changes in circulating cytokines (IL-1, IL-6, TNF, and IL-10), soluble cytokine receptors (TNF-RI, RII, and sIL-6R) and peripheral white blood cell (WBC) subset counts were followed up long-term (12 weeks) after cA2 therapy in them. Significant clinical responses (>20% improvement according to Paulus' criteria) were observed just after cA2 infusion and lasted more than 4 weeks in all patients, as reported elsewhere. Moreover, five of the eight patients showed prolonged clinical responses (>12 weeks). The elevated serum IL-6 and sTNF-RI (or RII) levels before treatment rapidly decreased after treatment. The serum IL-10 levels also significantly elevated before treatment. The elevations of serum IL-10 levels were augmented after treatment and stayed higher than the baseline in four patients with prolonged clinical responses. No significant TNF, IL-1 and -, or sIL-6R were detected in the sera of the patients before treatment and during the whole study period. On the other hand, peripheral lymphocytes as well as total WBC and neutrophils increased for 4 weeks after treatment. However, thereafter, only the lymphocyte count decreased gradually and stayed below the baseline long-term (12 weeks). FACS analysis revealed the predominance of T lymphocytes in the decrease in lymphocyte counts. These results suggest that the augmentation of IL-10 production and the decrease in T cells might partly contribute to the long-lasting efficacy of cA2 treatment in RA.  相似文献   
2.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
3.
A pathogenic role of precore-defective mutation in the onset of fulminant hepatitis B has been suggested. However, precore-defective mutants do not always cause fulminant hepatitis B and are not always isolated from affected patients. These findings strongly suggest the presence of some additional important mutations outside the precore region in fulminant hepatitis. In the present investigation an attempt was made to sequence the X open reading frame of hepatitis B virus DNA isolated from seven patients with fulminant hepatitis B and five patients with acute hepatitis B. The latter were used as controls. Since the X open reading frame encodes the X protein and contains the core promoter/enhancer II complex, some critical mutations may enhance or disrupt the replication and expression of hepatitis B virus DNA leading to fulminant hepatitis. A C-to-T substitution was found at nucleotide (nt) 1655, an A-to-T substitution at nt 1764 and a G-to-A substitution at nt 1766 in 4, 5 and 5 patients, respectively, out of the seven with fulminant hepatitis. These substitutions were not recognized in the patients with acute hepatitis. These mutations might change the function of the X protein and core promoter/enhancer II complex. It is suggested, therefore, that these mutations, as well as the precore-defective mutation, may play an important role in the pathogenesis of fulminant hepatitis. © Wiley-Liss, Inc.  相似文献   
4.
The present study investigates the effects of bis(7)-tacrine, a novel dimeric acetylcholinesterase inhibitor, on hydrogen peroxide(H2O2)-induced cell injury with comparison to the corresponding monomer, tacrine. Exposure of rat pheochromocytoma line PC12 cells to H2O2 induced significant cell damage. This reagent also caused redox desequilibrium as indicated by a decrease in activities of intracellular antioxidant enzymes such as glutathione peroxidase as well as catalase and an accumulation of malondialdehyde, a product of lipid peroxidation. Pretreatment of cells with bis(7)-tacrine or tacrine attenuated H2O2-induced cell toxicity, and bis(7)-tacrine demonstrated higher potency than tacrine in improving redox desequilibrium. These results suggest that bis(7)-tacrine and tacrine significantly protect against H2O2 insult, which might be beneficial for their potential usage in the prevention and treatment of Alzheimer's disease.  相似文献   
5.
In this study, we examined the degree of disruption of blood-brain barrier (BBB) in irradiated rat brains using P-glycoprotein, one of the functional molecules of BBB, as a marker. In the animal experiments, disruption of BBB has been mainly studied at the acute stage of brain edema caused by a lethal dose of irradiation. However, they do not mimic the clinical situation of radiotherapy for malignant brain tumors. Therefore, we examined effects of a clinically compatible dose of radiation on BBB. The rat hemisphere received a single application of 25 Gy of X-rays, and P-glycoprotein was analyzed 5 days later by immunohistochemistry and Western blotting. Immunoreactivity of P-glycoprotein was found to be strong in endothelial cells of the brain of the nonirradiated rat as well as in the nonirradiated hemisphere of the irradiated rat. In contrast, very weak or no immunoreactivity was observed in the majority of endothelial cells in the irradiated hemisphere. Western blotting quantitatively showed that P-glycoprotein in the irradiated hemisphere decreased to nearly 60% that of the controls. The present study indicated that even a clinically applicable dose of radiation causes early disruption of BBB in the rat model.  相似文献   
6.
Corticomuscular coherence measured between electroencephalography (EEG), magnetoencephalography, or local field potentials and electromyography (EMG) should be helpful in understanding the cortical control of movement. EEG-EMG coherence and phase spectra depend on the types of EEG derivation and current source density function of EEG appears to be the most appropriate for computation of EEG-EMG coherence. A new model for the interpretation of the phase spectra ("constant phase shift plus constant time lag model") shows that cortical surface negative potentials are phase-locked to EMG firing. There are functional differences of EEG-EMG coherence among the alpha, beta, and gamma bands suggesting differences in their possible generator mechanisms. Since corticomuscular coherence is a noninvasive measure of corticomotoneuronal function in a specific frequency range, clinical application of this method might be very fruitful in tremor research.  相似文献   
7.
Selective neuronal death in the CA1 sector of the hippocampus [delayed neuronal death (DND)] develops several days after transient global cerebral ischemia in rodents. Because NGF plays a potential role in neuronal survival, it was decided to study its effect in DND. We report here that intraventricular injection of NGF either before or after 5 min forebrain ischemia in the Mongolian gerbil significantly reduced the occurrence of DND. The tissue content of NGF in the hippocampus was decreased 2 d after ischemia and recovered to the preischemic level by 1 week. By the Golgi staining technique, changes first began in the dendrites of affected neurons as early as 3 hr. Such changes could be ameliorated by NGF treatment. Although previous knowledge of NGF is limited to the survival of cholinergic neurons in the CNS, it is assumed that other mechanisms must be operating in the hippocampus, for example, postsynaptic modification at dendrites or aberrant expression of NGF receptors possibly at the initial excitation period by glutamate. Furthermore, because previous work has shown that inhibition of protein synthesis reduces the occurrence of DND, a program leading to cell death might also be operating via de novo synthesis of certain protein(s), collectively termed "killer protein," because of a lack of NGF.  相似文献   
8.
BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with recurring inflammation of the colorectal mucosa. Recently, cytapheresis has emerged as a new treatment for patients with UC. Removal methods are mainly performed with beads [granulocyte and monocyte/macrophage adsorptive apheresis (GMCAP)] or filters [leukocytapheresis (LCAP)]. Both treatments have been reported to be effective for active UC. There have been few trials, however, comparing the efficacy of GMCAP and LCAP. In this study, we prospectively evaluated the efficacy of LCAP and GMCAP for the treatment of active UC. METHODS: Thirty-nine patients [18 male, 21 female; mean age 38.7 years; duration of disease 6 years; clinical activity index (CAI) >6 points] with moderate-to-severe active UC were randomly assigned to the LCAP (n=21) or GMCAP group (n=17). Adacolumn (cellulose acetate beads; Japan Immunoresearch Laboratories, Takasaki, Japan) for GMCAP and Cellsorba EX (polyethylene phthalate fibers; Asahi Medical Co. Ltd, Tokyo, Japan) for LCAP were used for leukocyte removal. Patients received two sessions of cytapheresis in the first week, followed by four weekly administrations. Steroid doses were tapered if patients achieved clinical improvement. When the CAI score had decreased by 5 points or more, the patient was considered to have improved. RESULTS: Thirteen patients in the GMCAP group and 14 in the LCAP group achieved clinical improvement. No significant difference was found in clinical response and clinical course between LCAP and GMCAP. Hemoglobin levels were significantly decreased immediately after one session of cytapheresis in the LCAP group. No severe adverse effects were observed in any of the patients. No significant differences were observed in any clinical parameters predictive of a response to either LCAP or GMCAP. But in all patients receiving cytapheresis, a high CAI score was a significant risk factor for treatment failure. All of the cytapheresis nonresponders had CAI scores >or=16. CONCLUSION: Both GMCAP and LCAP were effective treatments for active UC. Patients with severe UC and a high CAI score were, however, refractory to treatment.  相似文献   
9.
International Journal of Clinical Pharmacy - Background Renal anaemia worsens because of the uraemic status immediately before the initiation of haemodialysis. The haemoglobin level in patients...  相似文献   
10.
Mirror therapy using mirror visual feedback (MVF) has been applied to the stroke rehabilitation of hemiparesis. One possible mechanism of mirror therapy is the functional interhemispheric connectivity between sensorimotor areas via corpus callosum. To test this hypothesis, we investigated the MVF-induced motor learning in 2 patients with callosal disconnection. Callosal connection in patients was evaluated by clinical measures and the interhemispheric inhibition (IHI) using transcranial magnetic stimulation. Both patients suffered from somatosensory cognitive disconnection, and one showed the loss of IHI. Motor training with MVF significantly improved the motor behavior of both patients. Extending our previous study, the results of callosal patients suggested that the visual feedback through a mirror might play the crucial important role for the improvement of motor performance, rather than interhemispheric interaction via corpus callosum.  相似文献   
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