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81.
The disturbance of immune regulatory T cells is related to the pathogenesis of ulcerative colitis. Here we demonstrated and characterized the serum factor from ulcerative colitis patients that induced proliferation of intrathymic T cells. The factor isolated from the patient sera by a combination of gel filtration and anion-exchange chromatography induced proliferation of CD4+CD8 intrathymic T cells in the organ-cultured embryonic mouse thymus. Purification and amino acid sequence analysis of the serum factor demonstrated that the N-terminal 12 sequence was homologous to that of interleukin-7. SDS-PAGE and Western blot confirmed that purified serum factor was interleukin-7. Enzyme immunoassay demonstrated that the serum interleukin-7 concentration was significantly increased in the patients. PCR and Southern blot hybridization demonstrated that interleukin-7 mRNA expression was increased in the thymus tissues from patients but decreased in the colonic mucosa. Since interleukin-7 is a crucial cytokine for proliferation and differentiation of T cells in the thymus, the present study indicates that interleukin-7 may contribute to the disturbance of immune regulatory T cells in ulcerative colitis.  相似文献   
82.
We previously reported a simple and rapid method for HLA-DQA genotyping by digestion of polymerase chain reaction-amplified DQA genes with allele-specific restriction endonucleases. Here we report the application of this method to DP genotyping. The second exon of the HLA-DPB genes was selectively amplified from genomic DNAs of 72 HLA-D homozygous B-cell lines by the polymerase chain reaction method. Amplified DNAs were digested with ApaI, SacI, BstUI, FokI, and RsaI, which can recognize allelic sequence variations in the polymorphic segments of the DPB second exon and then subjected to electrophoresis in polyacrylamide gels. Sixteen different polymorphic patterns of the restriction fragments were found, and twelve were identical to patterns predicted from the known DNA sequences correlating with each HLA-DPw specificity defined by cellular typing. The other four patterns were distinct from those of the known DPw specificities, suggesting the presence of novel DP alleles. This polymerase chain reaction-restriction fragment length polymorphism method provides a simple and rapid technique for accurate definition of HLA-DP types at the nucleotide level, replacing the technically demanding method of primed lymphocyte typing.  相似文献   
83.
84.
The inhibitory effect of ONO-1078, a novel leukotriene (LT) receptor antagonist, was investigated on guinea pig lung anaphylaxis in vitro and in vivo. It was demonstrated that this compound could inhibit the late phase of contractile responses in Schultz-Dale reactions and endogenous LT-mediated bronchoconstrictions in passively sensitized guinea pigs, in a dose-dependent fashion, implying its clinical usefulness in the treatment of human bronchial asthma.  相似文献   
85.
86.
Splenic T cells were primed, after removal of alloreactive cells, to beef insulin on allogeneic antigen-presenting cells (APC). The fine specificity of in vitro secondary response was tested in combinations H-2b (responder) T cell-H-2k (nonresponder) APC, and vice versa, using separated chains of beef and pork insulin. The response in both combinations exhibited identical specificity patterns demonstrating that both responder and nonresponder APC could present the same array of insulin epitopes to allogeneic T cells. The determinants presented to allogeneic T cells include the A-chain loop epitope and the B-chain determinant(s) that were found to be immunogenic for H-2b and H-2d T cells, respectively, in the context of syngeneic major histocompatibility complex (HC) molecules. In addition, minor determinants were detected in the A chain outside the loop that are not immunogenic in syngeneic T cell-APC combinations. Inhibition of T cell proliferation with monoclonal antibodies has shown that class II MHC molecules of the nonresponder (Ak alpha Ak beta, Ek alpha Ek beta) as well as those of the responder APC (Ab alpha Ab beta) are equally capable of presenting virtually all insulin epitopes recognizable by T cells. The data, therefore, demonstrate that the selective recognition of different insulin epitopes observed in syngeneic or semisyngeneic T cell-APC combinations does not result from determinant selection at the level of APC.  相似文献   
87.
Two antigen systems (L29 & L30) expressed on two distinct human B cell subpopulations were identified by using BL1-4D6 and TB3-7D5 monoclonal antibodies, respectively. L29 was expressed on approximately one-third of B cells in human lymphoid tissues. These B cells associated with L29 were large activated B cells located in the germinal centres of lymphoid follicles. L30, on the other hand, existed on approximately two-thirds of B cells mainly located in the mantle zone of lymphoid follicles, most of which also expressed IgM and IgD on their cell membrane. In addition, L30 was shared on mature granulocytes. With the use of polyclonal activators such as pokeweek mitogen (PWM) and protein A-bearing staphylococci (SAC), L29 antigen was inducible on PWM- or SAC-stimulated B cells in correspondence with the emergence of Tac and T10 antigens of these B cells. In contrast, L30 antigen on the B cells stimulated by the polyclonal activators was decreased in its expression and was finally lost from these B cells. Although none of L29 and L30 was expressed on normal, non-activated human thymus and peripheral T cells, L29 but not L30 was expressed on concanavalin A-activated T cells. Immunochemical studies showed that L30 consist of a single polypeptide with mol. wt of 40,000. L29 antigen is presently under study.  相似文献   
88.
Summary Effect of chronic clonidine treatment on the response to glucose of rat pancreatic B-cells was investigated. Clonidine treatment was carried out for 10 days by dissolving the drug into drinking water at a concentration of 10 g/ml. Control rats were given drug-free tap water. Serum insulin responses to glucose (750 mg/kg, i. v.) of clonidinetreated rats were much smaller than those of control rats. However, after 1 day's withdrawal of clonidine, the rise in the serum insulin level induced by glucose was approximately 2-fold larger in clonidine-treated rats as compared to that in control rats. Since clonidine treatment decreased body weight of the rat by 10%–20% in 10 days, the same experiments were carried out with rats whose body weight loss was made comparable to that of clonidine-treated rats by restricting food for 10 days. Then, some animals of the group thus treated had food-restriction discontinued for 1 day. In both of the above two groups, no increment in glucoseinduced rise in serum insulin level was observed. Islets of Langerhans isolated from clonidine-treated rats showed pronounced insulin releasing capacity in response to glucose. Insulin content per islet of the clonidine-treated rat was slightly larger than that of control rat. These results indicate that the enhancement of serum insulin response to glucose following clonidine treatment is mainly attributable to the hyper-responsiveness developed in the pancreatic B-cells.  相似文献   
89.
Regional cerebral blood flow was measured by the 133Xe inhalation method in 20 young patients with moyamoya disease and five young healthy volunteers. Most patients showed low values of mean hemispheric blood flow in both hemispheres. Regional cerebral blood flow was at a low value in the upper frontal region and at an almost average value in the posterotemporal and occipital regions, which was different from the "hyperfrontal" pattern in healthy volunteers. Regional cerebral blood flow was reduced evenly by hyperventilation. By 5% CO2 inhalation, regional cerebral blood flow was increased in the temporooccipital regions and was nearly unchanged or decreased in the frontal region.  相似文献   
90.
Summary A 23-year-old man with myopathy with tubular aggregates had suffered from exercise-induced muscle cramps for 1 year. His general and neurological findings were normal. Laboratory investigations were within normal limits except for a slightly elevated serum creatine kinase level. Muscle biopsy showed some small angular fibres and scattered type 2B fibres with prominent tubular aggregates originating from the sarcoplasmic reticulum. Since the muscle fibres contracted at a lower concentration of caffeine, increased muscle fibre sensitivity to caffeine is probably related to muscle cramps in this disorder. Tubular aggregates are then secondarily formed in the muscle fibres.  相似文献   
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