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161.
Summary Restriction fragment length polymorphisms (RFLPs) of the CYP11B1 gene were studied in Japanese using cDNA clone P450c11 as a probe. Genomic DNAs from 60 unrelated Japanese individuals were digested with 8 different restriction enzymes and analyzed by Southern blot hybridization. Two RFLPs were detected inMspI digests of the DNA. One(A) was characterized by polymorphic bands at 3.4 and 2.5 kilobasepairs (kb) and the other (B) by polymorphic bands at 1.7 and 1.2 kb. The third RFLP was observed inPvuII-digested samples and was polymorphic at 5.8 and 4.0 kb bands. Two of the three RFLPs found, RFLP (A) and (C), have not been described in the only previous report which was based on Caucasian samples. We also examined the RFLPs of a 3 generation family of 11-hydroxylase deficiency caused by an abnormality of the CYP11B1 gene. All the family members were homozygous in all three RFLPs and was thus not informative.  相似文献   
162.
 The effects of potassium channel opening drugs and intracellular nucleotides on the ATP-sensitive K+ (KATP) channel composed of SUR2A and Kir6.2 in HEK293T cells were examined using the patch-clamp technique. The SUR2A/Kir6.2 channel was activated effectively by pinacidil, marginally by nicorandil but not by diazoxide. The pinacidil-activated channel currents were inhibited by glibenclamide with a K i value of 160 nM. Upon formation of inside-out (I-O) patches, spontaneous openings of the channels appeared, which were inhibited by intracellular ATP (ATPi) equipotently in the presence and in the absence of intracellular Mg2+ (Mg2+ i). The channel activity ran-down gradually in I-O patches. The run-down channels could be reactivated by ATPi only in the presence of Mg2+ i. Uridine 5’-diphosphate (UDP) antagonized the ATPi-mediated inhibition of the channel activity before run-down. After run-down, UDP activated the channel without antagonizing ATPi-mediated channel inhibition. Thus, the SUR2A/Kir6.2 reproduced the major properties of the native cardiac KATP channel well in terms of nucleotide regulation and pharmacology, and therefore can be a useful tool with which to elucidate the molecular mechanisms characterizing the KATP channel. Received: 24 October 1997 / Received after revision and accepted: 4 December 1997  相似文献   
163.
Signaling by tumor necrosis factor type 1 receptor (TNFR-1) is required for the initiation of liver regeneration after partial hepatectomy. Using knockout mice that lack either TNFR-1 or TNFR-2, we determined whether signaling through TNF receptors is important for liver injury and hepatocyte proliferation induced by carbon tetrachloride (CCl4). Lack of TNFR-1 inhibited hepatocyte DNA synthesis after CCl4 injection. At 44 hours after the injection, replication of hepatocytes in TNFR-1 was 50% to 90% lower than in wild-type (WT) animals, depending on the dose injected. In WT animals, hepatocyte replication was essentially completed by 4 days after CCl4 injection, but replication at a low level persisted in TNFR-1 mice for at least 2 weeks. TNFR-1 knockout mice had little detectable NF-kappa B and STAT3 binding during the first 5 hours after CCl4, high plasma TNF, and reduced levels of plasma interleukin (IL)-6 and liver IL-6 mRNA. Injection of IL-6 30 minutes before CCl4 administration corrected the deficiency of hepatocyte replication at 44 hours and restored STAT3 binding to normal levels. In contrast, mice lacking TNFR-2 did not differ significantly from WT mice in NF-kappa B and STAT3 binding, IL-6 and TNF levels, or hepatocyte replication. Although AP-1 binding was induced in WT TNFR-1 and TNFR-2 knockout mice, binding in TNFR-2 knockouts was lower than in WT mice. C/EBP binding was much lower in TNFR-1 and TNFR-2 knockout mice than in WT mice. As assessed by morphological analysis and alanine aminotransferase levels, the acute injury caused by CCl4 appeared to be similar in the three groups of animals, but subsequent regeneration was impaired in mice lacking TNFR-1. We conclude that a TNFR-1 signaling pathway involving NF-kappa B, IL-6, and STAT3 is an important component of the hepatocyte mitogenic response induced by CCl4 injury in mouse liver.  相似文献   
164.
Using 2-dimensional electrophoresis and ion-pair chromatography, we have identified elements of proliferating cell nuclear antigen (PCNA) multiprotein complexes that are reactive to antibodies in sera from patients with systemic lupus erythematosus. Among the various elements of the complexes, a 37 kDa protein (PI 8.5) that specifically reacted with SLE sera, but not with sera from patients with other connective tissue diseases, was identified as glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Immunoblot analysis showed that SLE sera reactive with the 37 kDa protein specifically reacted with GAPDH, as did anti-GAPDH mAbs. The purified autoantibodies to GAPDH from lupus serum showed both nuclear speckled and cytoplasmic staining patterns in immunofluorescence on Hep-2 cells. In addition, enzyme-linked immunosorbent assay (ELISA) revealed the presence of anti-GAPDH autoantibodies in 47% of lupus patients. Longitudinal analysis of the reactivity of lupus sera to PCNA complexes showed the autoimmune response to spread from GAPDH to other elements of PCNA complexes, and the presence of anti-GAPDH antibodies was significantly correlated with increased levels of serum PCNA. Taken together, these findings suggest that GAPDH interacting with PCNA in association with its cellular function is a novel autoantigen recognized by lupus sera, and that GAPDH thus plays an important role in the induction of autoimmune responses against the PCNA complex.  相似文献   
165.
166.
Priming effect of RANTES on eosinophil oxidative metabolism   总被引:1,自引:0,他引:1  
Background RANTES has been shown to possess chemotactic activity for eosinophils, which have also been considered to play a role in allergic inflammation through reactive oxygen species. Thus, in this study, we examined the effect of RANTES on radical oxygen products from eosinophils.
Methods Purified eosinophils by CD16-negative selection or an eosinophilic cell line (EoL-1) were incubated with or without RANTES (2.5 x 10−6). To the mixture of eosinophils and luminol, calcium ionophore (A23187) or opsonized zymosan (OZ) was added, and radical oxygen products were determined by luminol-dependent chemiluminescence for 600 s.
Results Eosinophil-mediated radical oxygen products of untreated eosinophils produced with A23187 gave a peak value of 14.09 + 2.40 (mean±SE, n = 12) relative light units (RLU) and an integrated value of 3232.20 + 513.09 RLU. However, with treatment with RANTES, a peak value of 18.66 + 2.40 RLU and an integrated value of 5301.05 ±561.02 RLU were obtained. Eosinophil oxidative metabolism-induced A23187 or OZ was apparently augmented by the preincubation with RANTES. In addition, the radical oxygen products of EoL-1 showed similar results.
Conclusions Thus, we concluded that RANTES may play an important role the pathogenesis of allergic inflammation through its involvement in eosinophil activation, as evidenced by oxygen products, as well as in selective eosinophil infiltration as selective eosinophil chemoattractant.  相似文献   
167.
The cytoarchitectonic subnuclear organization of the parabrachial nucleus (PB) surrounding the brachium conjunctivum (BC) in the monkey was examined using the Nissl method and the anterograde axonal flow method. PB of the monkey could be divided into the following subnuclei: the dorsal area (DPBM) along the medial surface of the medial three-fourths of BC in the caudal half of medial PB (PBM), the ventral area (VPBM) along the medial surface of the lateral one-fourth of BC in the rostral two-thirds of PB, the ventrolateral part of lateral PB (PBL) lateral to BC throughout PB (EL), the ventral part of the rostral half of PBL ventral to EL (EXL), the medial part of middle PBL along the dorsal surface of BC (VL), the dorsal and lateral marginal part of PBL in the rostral two-thirds of PB (DL), the cell cluster in the dorsomedial part of the rostral half of PBL between VL and DL (CL), the dorsocentral part appearing at the level of root exit of the trochlear nerve between DL and CL and extending to the rostral end of PBL (IL), the area between DL and IL in the rostral one-seventh of PBL (SL), and K?lliker-Fuse nucleus (KF) ventral to EL and BC in the middle one-third of PB and lateral to the lateral pontine tegmentum. After the injection of biotinylated dextran amine into the upper cervical segments, labeled fibers terminated in each subdivision of PB with different densities; most heavily in IL, more heavily in DL and KF, moderately in EL and VPBM, and scarcely in the rest of PB. The present study demonstrated for the first time the subdivisions of PB in the monkey, which were essentially common to those of the rat based on the cytoarchictecture of PB and spinal fiber terminals in it.  相似文献   
168.
E Wada  A Urisu  Y Kondo  F Horiba  M Tsuruta  T Yasaki  S Masuda  K Yamada  T Kozawa  Y Hida 《Arerugī》1991,40(12):1493-1499
IgE-mediated mechanisms are important in immediate hypersensitive reactions (IHR) to buckwheat. However, a part of subjects with high IgE for buckwheat show no IHR to buckwheat ingestion. Inspite of cross-allergenicity between buckwheat and rice, rice ingestion rarely induces IHR even in subjects with high IgE for rice unlike buckwheat-induced IHR. We speculated that there were some relationships between the presence of IHR to buckwheat and recognition of cross-allergenic determinants on buckwheat components with rice components. We examined IgE-RAST for rice in 58 subjects with positive IgE-RAST for buckwheat. IgE-RAST for Dermatophagoides pteronyssinus (Dp), egg white and cow's milk as unrelated antigens with rice were also assessed for a comparison. Subjects (n = 33) without IHR to buckwheat showed higher IgE-RAST values for rice than those (n = 25) with IHR, whereas there were no differences in IgE-RAST values for Dp, egg white and cow's milk between two groups with and without IHR. IgE-RAST values for buckwheat showed significant close correlations to those for rice in subjects without IHR to buckwheat but not in those with IHR. There were no significant correlations between IgE-RAST values for buckwheat and for Dp, egg white or cow's milk in both groups with and without IHR. These results suggested that the IgE from subjects without IHR to buckwheat recognized cross-allergenic determinants with rice on the buckwheat components.  相似文献   
169.
Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohns disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE. Because these reports on association were not always evaluated in multiple ethnic groups and because ethnic difference in allele frequency of the variants has been also reported, we investigated allele frequencies of nine SNPs in four autoimmune-disease-associated loci in Caucasian, African-descent, and Japanese populations. Although SNPs in PADI4 had similar allele frequency among three groups [maximal difference 11%; (P >0.05)], the other three loci revealed statistically significant allele frequency differences (maximal difference 39% (P <0.00001), 13% (P <0.00001), and 8% (P <0.00001) in SLC22A4, PDCD1, and PTPN22, respectively). Of note, three SNPs in the three loci that had allele frequency more than 8% in the Caucasian population were either not polymorphic at all or extremely rare in the Japanese population. Our data suggest that ethnic variations of polymorphisms should be evaluated in detail, and differences should be incorporated into investigations of susceptibility variants for common diseases.  相似文献   
170.
The DA strain of Theiler's murine encephalomyelitis virus (DAV) causes a chronic demyelinating disease in susceptible mouse strains. To elucidate the pathogenesis of DAV-induced demyelination, the authors investigated the spatial and chronologic relationship between virus (antigen and RNA), myelin-specific mRNAs, and demyelination in DAV-infected mice using immunohistochemistry, in situ hybridization, and slot blot hybridization analyses. In spinal cord white matter, viral RNA was detected easily in ventral root entry zones 1 to 2 weeks after infection. Viral RNA increased to maximum levels by 4 weeks after infection, which was associated with inflammation and mild demyelination. At 8 to 12 weeks after infection, when demyelination became most extensive, viral RNA was significantly decreased. Demyelination did not chronologically or spatially parallel the presence of viral RNA within the spinal cord. Decrease of myelin-specific mRNAs, including myelin-basic protein and proteolipid protein mRNAs, was observed within the demyelinating lesions with or without detectable viral RNA. These results indicate that a viral infection of white matter in the early phase of the infection initiates spinal cord disease leading to demyelination, but later an ongoing immunopathologic process contributes to the presence of extensive demyelination.  相似文献   
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