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The authors have previously reported that homologous immunoglobulin (Ig)G reduces the occurrence of dextran sulfate sodium (DSS)-induced colitis, mainly by suppressing recruitment of immunocompetent cells into colitis lesions. However, the mechanisms of cell recruitment and of its suppression by IgG remain unclear. In addressing these questions, this study focused on the activation of T cells in the presence of macrophages. The authors found that [3H]-thymidine uptake of T cells from DSS-induced colitis mice, but not from normal mice, was significantly enhanced when cultured with DSS-pulsed macrophages. From the profile of cytokine production, it was suggested that T helper 1 (Th1)-type cells become predominant during stimulation. Addition of homologous IgG significantly suppressed T cell proliferation in a dose-dependent manner, while no suppressive effect was observed with heterologous IgG. Mouse IgG F(ab')2, but not Fc, fragments partially mimicked the suppressive effect of whole IgG. These findings provide evidence that Th1-type cells may play an important role in the development of DSS-induced colitis and that homologous IgG exerts its protective action at least in part through the F(ab')2 portion.  相似文献   
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We have measured the direct effects of propofol 10–7-10–4mol litre–1 on isolated canine cerebral, coronary, mesenteric,femoral and renal arteries. In arterial strips precontractedsubmaximally with potassium chloride or prostaglandin F2  相似文献   
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In the present study, we examined the effect of amantadine on extracellular dopamine levels in the rat striatum using an in vivo microdialysis. Perfusion of amantadine (0.1–1 mM) through the microdialysis probe caused an increase both in extracellular dopamine and glutamate levels in rat striatum. Amantadine was found to increase extracellular dopamine concentration in Ca2+-dependent manner, but the effect was not abolished by ω-conotoxin. Although intraperitoneal administration of MK-801 [(+)-5-methyl-10,11-dihydroxy-5H-dibenzo(a,d)cyclohepten-5,10-imine] alone could not significantly alter the concentration of dopamine, it attenuated amantadine-induced increase in dopamine level. These findings suggest that an interaction between dopaminergic and glutamatergic neurotransmission is an important component in the regulation of striatal dopamine levels. Copyright © 1996 Elsevier Science Inc.  相似文献   
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Hypertrophic cardiomyopathy and dilated cardiomyopathy are two major clinical phenotypes of “idiopathic” cardiomyopathy. Recent molecular genetic analyses have now revealed that “idiopathic” cardiomyopathy is caused by mutations in genes for sarcomere components. We have recently reported several mutations in titin/connectin gene found in patients with hypertrophic cardiomyopathy or dilated cardiomyopathy. A hypertrophic cardiomyopathy-associated titin/connectin mutation (Arg740Leu) was found to increase the binding to actinin, while other dilated cardiomyopathy-associated titin/connectin mutations (Ala743Val and Val54Met) decreased the binding to actinin and Tcap/telethonin, respectively. We also reported several other mutations in the N2-B region of titin/connectin found in hypertrophic cardiomyopathy and dilated cardiomyopathy. Since the N2-B region expresses only in the heart, it was speculated that functional alterations due to the mutations cause cardiomyopathies. In this study, we investigated the functional changes caused by the N2-B region mutations by using yeast-two-hybrid assays. It was revealed that a hypertrophic cardiomyopathy-associated mutation (Ser3799Tyr) increased the binding to FHL2 protein, whereas a dilated cardiomyopathy-associated mutation (Gln4053ter) decreased the binding. In addition, another TTN mutation (Arg25618Gln) at the is2 region was found in familial DCM. Because FHL2 protein is known to tether metabolic enzymes to N2-B and is2 regions of titin/connectin, these observations suggest that altered recruitment of metabolic enzymes to the sarcomere may play a role in the pathogenesis of cardiomyopathies.  相似文献   
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To clarify the significance of basic fetoprotein (BFP) in lymphocytes, we investigated whether BFP is produced in lymphocytes during blastic transformation. Peripheral blood lymphocytes obtained from 14 adults were cultured under the stimulation of lectins. The concentration of BFP in the culture medium (extracellular BFP) was estimated serially. The incorporation of [6-3 H] thymidine was assayed simultaneously. The intracellular BFP was measured by dual flow cytometry for DNA and BFP. A lymph node was studies immunohistochemically. Serum BFP was measured in four cases of lumphocytic leukaemia. In two cases, dual staining was performed. The intracellular BFP of the mitogen-stimulated lymphocytes was increased within 24 h. The extracellular BFP was increased exponentially from 72 h. The extracellular BFP at 96 h did not correlate with the [3H]-thymidine incorporation. The intracellular BFP increase began in G1 phase. Immunostaining showed that the B cells also produced BFP. The
serum BFP level in leukaemia was high in 1 of 4 cases and the leukaemic cells in two cases showed high intracellular BFP content. These observations indicate that BFP is produced in activated human lymphocytes and in lymphocytic leukaemic cells. The production of BFP during blastic transformation will be a useful new in vitro model for studying the biological role of BFP, and BFP labelling may offer some new possibilities for study of lymphocytes.  相似文献   
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Infection is a common complication of stroke and is associated with unfavorable outcomes. Although nutritional intervention reduces the risk of postoperative infection, the impact of specific nutritional products remains unclear. From a hospital management perspective, we aimed to determine whether the provision of specific types of enteral nutrition in acute stroke patients affects infection control and hospital costs. In all, 45 acute hemorrhagic stroke patients receiving enteral nutrition in a single center (April 2017–March 2019) were retrospectively assessed. Patients were divided into two groups according to nutritional interventions: the 1.0-group with general nutrition (1.0 kcal/mL) (24 patients) and the 1.5+α-group with an initial high-protein, whey peptide-digested liquid diet (1.5 kcal/mL), followed by a highly fermentable fiber-containing liquid diet (1.5 kcal/mL initiated after 4 days) (21 patients). Changes in body mass index (BMI), duration of antibiotic use, incidence of postoperative infection, and medical cost were evaluated. Baseline patient characteristics were similar between groups. The mean BMI change was lower in the 1.5+α-group than in the 1.0-group, and the mean duration of antibiotic use throughout hospitalization was 12.8 and 18.3 days, respectively. Antibiotic use in the 1.5+α-group was lesser than that in Japanese patients from other hospitals. The incidence of postoperative infections was lower in the 1.5+α-group. Injection costs for the 1.5+α group (615 USD/patient) were lower than those for the 1.0-group. Enteral nutrition provided to acute stroke patients reduced the risk of hospital infection and medical costs.  相似文献   
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In 45 healthy Japanese volunteers, it was found that personsheterozygous for ALDH2 (ALDH2*1/ALDH2*2), and also either heterozygousor mutant homozygous for CYP2E1 (C2/C2 or C1/C2 can drink muchmore alcohol, even with (slight) flushing, than persons heterozygousfor ALDH2 (ALDH2*1/ALDH2*2) and normal homozygous for CYP2E1(C1/C1)  相似文献   
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