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T Sumida

Publications and source records attributed to T Sumida.

At least 109 records · Page 6Linked to original sources
PubMed1998

Extraction of cytokeratin from the human submandibular gland and its electrophoretic analysis.

We evaluated a method for extracting cytokeratin (CK) from the normal human submandibular gland and analyzed CK distribution by one- and two-dimensional electrophoresis. Four submandibular glands without histological changes under a light microscope were used as specimens. Intermediate filamentous protein was extracted by a prior modified method CK was not adequately extracted in 1-2% sodium dodecyl sulfate -5% 2-mercaptoethanol solution. On the other hand, 11 bands with molecular weights of 40-58 K were obtained after extraction in 9.5 M urea -5% 2-mercaptoethanol solution. Although fragmentation of cytoskeletal protein was observed, there were no differences in bands according to the strength of homogenization. This fragmentation seemed to be due to restriction degradation by protease. Immunoblotting revealed the reaction of this CK extract to 2 pan-CK antibodies, i.e., K8.13, which recognizes type II basic CK, and C-11, which recognizes CK4, CK5, CK6, CK8, CK10, CK13, CK18. Among monospecific antibodies, anti-CK7 (LDS-68), CK8 (M20), CK13 (KS-1A3), CK18 (CY-90), and CK19 (BA17) antibodies showed positive reactions. Glial fibrillary acidic protein, neurofilament (NF) 68 K, NF160 K, or NF200 K showed no reactions. These results of one- and two-dimensional electrophoretic analysis suggest the presence of CK5, CK7, CK8, CK13, CK14, CK15, CK17, CK18, and CK19 in the normal submandibular gland.

Antibodies, Monoclonal↗
PubMed1997

T cell receptor of Fas-sensitive T cells in rheumatoid synovium.

Apoptosis is found in synoviocytes and CD3+ T cells in the synovium of patients with rheumatoid arthritis (RA). To analyze the pathogenesis of apoptosis in rheumatoid synovium, we examined the expression of Fas Ag, Fas ligand (Fas-L), and TCR on T cells susceptible to anti-Fas mAbs. Fas Ag is expressed on 40 to 60% of CD3+ T cells in the synovium as measured by immunohistochemical and flow cytometry methods. It was observed by the reverse transcription-PCR method that Fas-L is overexpressed on T cells infiltrating the rheumatoid synovium. These results suggest that apoptosis in RA synovium is mediated by the Fas/Fas-L pathway. PCR-single-strand conformation polymorphism clearly demonstrated that more than 50% of T cells that accumulate in synovium are removed by incubation with anti-Fas mAbs for 24 h in vitro, indicating that these cells are Fas sensitive. Junctional sequence analysis revealed several conserved amino acids motifs (ERxxxSMNTE, IAAEGLLG, QxEGxD, VPD, TLAGxYNEQ, EPSE, LTNxGEL, QGK, NIP, GLL, and KWT) in the CDR3 region of accumulated Fas-sensitive T cell clones, whereas these motifs were not detected in Fas-resistant clones. In conclusion, our findings support the notion that Fas-sensitive T cells in rheumatoid synovium are generated by Ag stimulation and recognize relatively limited T cell epitopes on autoantigens, suggesting that susceptibility to anti-Fas mAbs might be a selection marker for activated autoreactive T cells in RA.

Aged↗
PubMed1997

TCR in Fas-sensitive T cells from labial salivary glands of patients with Sjögren's syndrome.

Apoptosis is found in labial salivary glands of patients with Sjogren's syndrome (SS). To analyze the pathogenesis of apoptosis in labial salivary glands of SS patients, we examined the expression of Fas Ag and Fas ligand (FasL) and TCR on T cells susceptible to anti-Fas mAbs (CH-11). Fas Ag is expressed on epithelial cells and mononuclear cells in the salivary glands as observed by an immunohistochemical method. FasL is over-expressed specifically on T cells infiltrating into the labial salivary glands as seen by an reverse transcription-PCR method. These results suggest that apoptosis in SS lips is mediated by a Fas/FasL pathway. PCR single-strand conformation polymorphism (SSCP) clearly demonstrated that more than 40% of the T cells accumulated in labial salivary glands are deleted by incubation with CH-11 for 24 h in vitro, indicating that these expanded cells are Fas sensitive. junctional sequence analysis showed that the same conserved amino acid motifs (LAGG, RLA, SLG, QGPG, PGG, GGE, RGR, KPG, AGD, and MLG) in complementarity determining region 3 (CDR3) are found in Fas-sensitive T cell clones, whereas they are not detected in Fas-resistant clones, suggesting that Fas-sensitive T cells recognize restricted T cell epitopes on autoantigens. In conclusion, the findings suggest that Fas-sensitive T cells in labial salivary glands of SS patients are generated by Ag stimulation and might function as autoreactive T cells.

Amino Acid Sequence↗
PubMed1997

Chemoprevention of 4-nitroquinoline 1-oxide-induced oral carcinogenesis in rats by flavonoids diosmin and hesperidin, each alone and in combination.

The modifying effects of the two flavonoids diosmin and hesperidin given during the initiation and postinitiation phases of oral carcinogenesis initiated with 4-nitroquinoline 1-oxide (4-NQO) were investigated in male F344 rats. The compounds were tested alone and in combination. At 6 weeks of age, animals were divided into experimental and control groups and fed diets containing 1000 ppm diosmin and 1000 ppm hesperidin and a diet containing both compounds (900 ppm diosmin and 100 ppm hesperidin). At 7 weeks of age, all animals except those treated with each test chemical alone and control groups were given 4-NQO (20 ppm) in the drinking water for 8 weeks to induce oral cancer. Starting 7 days before the 4-NQO exposure, groups of animals were fed the diets containing test chemicals for 10 weeks and then switched to the basal diet. Starting 1 week after the cessation of 4-NQO exposure, the groups given 4-NQO and a basal diet were switched to the diets containing diosmin, hesperidin, or diosmin combined with hesperidin and maintained on these diets for 22 weeks. The other groups consisted of rats given diosmin (1000 ppm), hesperidin (1000 ppm), and the combination regimen of these two compounds (900 ppm diosmin with 100 ppm hesperidin) alone, and untreated rats. All animals were necropsied at the termination of the study (week 32). The incidences of tongue lesions (neoplasms and preneoplasms), polyamine levels in the tongue tissue, and cell proliferation activity estimated by a 5-bromodeoxyuridine-labeling index and by morphometric analysis of silver-stained nucleolar organizer regions protein were compared among the groups. Feeding of both compounds singly or in combination during the initiation phase caused a significant reduction in the frequency of tongue carcinoma [diosmin, 68% reduction (P < 0.01); hesperidin, 75% reduction (P < 0.005); and the combination regimen, 69% (P < 0.05)]. When fed the test compounds singly or the combination regimen after 4-NQO exposure, the frequency of tongue cancer was also decreased [diosmin, 77% reduction (P < 0.005); hesperidin, 62% reduction (P < 0.05); and the combination regimen, 77% (P < 0.005)]. The incidences of oral preneoplasia (hyperplasia and dysplasia) in these groups were also decreased when compared with carcinogen controls (P < 0.05-P < 0.001). There were no pathological alterations in rats treated with test compounds or the combined regimen alone or those in an untreated control group. Dietary administration of these compounds significantly decreased the expression of cell proliferation biomarkers (5-bromodeoxyuridine-labeling index and silver-stained nucleolar organizer regions protein number) of the nonlesional tongue squamous epithelium (P < 0.05). Also, polyamine concentrations in the oral mucosa were lowered in rats given the carcinogen and test compounds, alone and in combination, compared with those of rats given 4-NQO alone (P < 0.05). These findings suggest that supplementation with the flavonoids diosmin and hesperidin, individually and in combination, is effective in inhibiting the development of oral neoplasms induced by 4-NQO, and such inhibition might be related to suppression of increased cell proliferation caused by 4-NQO in the oral mucosa.

4-Nitroquinoline-1-oxide↗
PubMed1997

Accumulation of soluble Fas in inflamed joints of patients with rheumatoid arthritis.

OBJECTIVE: To examine the concentration of the soluble form of the Fas molecule (sFas) in the serum and synovial fluid of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). METHODS: The concentration of sFas in the serum of 15 normal subjects and in the synovial fluid and serum of 45 RA patients and 13 OA patients was determined. The erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, and the level of several cytokines in serum and synovial fluid were also determined. RESULTS: The synovial fluid concentration of sFas was higher in RA than in OA patients (P < 0.005). The synovial fluid level of sFas correlated weakly with serum levels of CRP (r = 0.541), the ESR (r = 0.499), and with synovial fluid levels of interleukin-2 (IL-2) receptor (r = 0.544), IL-6 (r = -0.529), and intercellular adhesion molecule 1 (r = 0.514). Reverse transcription-polymerase chain reaction analysis revealed that synovial cells and infiltrating mononuclear cells expressed sFas messenger RNA in RA patients. CONCLUSION: Our data suggest that accumulation of sFas in the joint cavity of RA patients may inhibit apoptosis and exacerbate the inflammatory process.

Aged↗
PubMed1997

Direct evidence of high DNA binding activity of transcription factor AP-1 in rheumatoid arthritis synovium.

OBJECTIVE: To investigate the possible activation of transcription factor AP-1 in rheumatoid arthritis (RA) and its involvement in the pathogenesis of RA. METHODS: Synovial tissues and peripheral blood samples were obtained from 25 patients with RA and 5 patients with osteoarthritis (OA) during arthroplasty and synovectomy. The synovial tissue was digested with collagenase and separated into adherent and nonadherent cells by plastic-adhesion methods. Nuclear extracts obtained from each sample were examined by electrophoretic mobility shift assay to determine the DNA binding activity of AP-1. The expression of c-fos and c-jun messenger RNA (mRNA) was examined by in situ reverse transcription assay. RESULTS: A markedly high DNA binding activity of AP-1 was detected in the synovial tissues of RA patients, while virtually no activity or only a little activity was observed in OA patients. Following separation of adherent and nonadherent cells, the AP-1 activity was mainly detected in adherent cells, which consisted of synovial cells and macrophages. However, the activity was significantly higher in the mononuclear cells infiltrating into RA synovium than in RA peripheral blood mononuclear cells. The high DNA binding activity of AP-1 in RA correlated with the expression of c-fos and c-jun mRNA in situ. Furthermore, AP-1 binding activity also correlated with disease activity. CONCLUSION: In RA synovium, AP-1 DNA binding activity was constitutively up-regulated. These findings suggest that AP-1 may play an important role in the pathogenesis of RA, including synovial hyperplasia and abnormal immune responses.

Aged↗
PubMed1997

Selective activation of the JNK/AP-1 pathway in Fas-mediated apoptosis of rheumatoid arthritis synoviocytes.

OBJECTIVE: To evaluate the Fas-dependent signaling pathway, we examined the involvement of protein tyrosine phosphorylation and the DNA binding activity of AP-1 in rheumatoid arthritis (RA) cultured synovial cells. METHODS: The number of dead cells was counted after treatment with anti-Fas antibody in the presence of protein tyrosine kinase or phosphatase inhibitor. Protein tyrosine phosphorylation in synoviocytes after Fas ligation was examined by immunoblot and immunoprecipitation analyses. The DNA binding activity of AP-1 was examined by electrophoretic mobility shift assay. RESULTS: Treatment with the protein tyrosine phosphatase inhibitor, orthovanadate, significantly enhanced the apoptosis of RA synoviocytes after Fas ligation. Ligation of the Fas molecule on RA synoviocytes induced a rapid tyrosine phosphorylation of JNK (c-Jun amino-terminal kinase) and formation of the AP-1 transcription factor. CONCLUSION: Our results strongly suggest that the JNK/AP-1 signaling pathway is activated during the process of Fas-mediated apoptosis of RA synovial cells.

Apoptosis↗
PubMed1997

Transcriptional regulation of the HOX4C gene by basic fibroblast growth factor on rheumatoid synovial fibroblasts.

OBJECTIVE: To examine the expression of genes of the HOX D cluster in the synovial tissue of patients with rheumatoid arthritis (RA), and to determine whether basic fibroblast growth factor (bFGF) influences the expression and transcriptional regulation of the gene. METHODS: The expression of genes of the HOX D cluster, including HOX4C, HOX4D, HOX4H, and HOX4I, was determined in the synovium of 4 patients with RA and 4 with osteoarthritis (OA) by in situ reverse transcription (RT) and RT-polymerase chain reaction (RT-PCR). The induction of HOX4C messenger RNA (mRNA) by bFGF was determined by RT-PCR. The binding activity of a transcriptional regulator of the HOX4C gene, C2, was analyzed by the mobility shift assay. NIH-3T3 cells transfected with a construct containing C2 binding sequence were incubated with bFGF, and the activity of the reporter was measured by luciferase assay. RESULTS: Using an in situ RT assay, specific expression of HOX4C mRNA was detected in 3 of 4 RA synovial samples, whereas none of the OA synovia expressed HOX4C. HOX4D, HOX4H, and HOX4I genes were expressed in all synovial samples from RA and OA patients. The presence of HOX4C mRNA was also confirmed by RT-PCR and Southern blotting. Treatment with bFGF increased the expression of HOX4C mRNA in RA fibroblasts. The mobility shift assay and luciferase assay showed that bFGF enhanced C2 binding activity and significantly increased the transcriptional activity on RA fibroblasts. CONCLUSION: Our findings suggest that HOX4C is involved in synovial hyperplasia, and that the transcriptional regulation of HOX4C genes by bFGF may play a crucial role in the pathogenesis of RA.

Arthritis, Rheumatoid↗
PubMed1997

Modulation of N-methyl-N-amylnitrosamine-induced rat oesophageal tumourigenesis by dietary feeding of diosmin and hesperidin, both alone and in combination.

The modifying effects of flavonoids diosmin and hesperidin during the initiation and post-initiation phases of oesophageal carcinogenesis initiated with N-methyl-N-amylnitrosamine (MNAN) were investigated in male Wistar rats. At 7 weeks of age, all animals except those treated each test chemical alone and control groups were given weekly intraperitoneal injections of MNAN (12.5 mg/kg body weight/injection) for 12 weeks to induce oesophageal neoplasms. For examining the modifying effects of 'initiation' treatment of test compounds, groups of animals were fed the diets containing 1000 ppm diosmin and 1000 ppm hesperidin, and the diet containing both compounds (900 ppm diosmin and 100 ppm hesperidin) for 13 weeks, starting 7 days before the MNAN dosing and then switched to the basal diet. For examining the modifying effects of 'post-initiation' treatment of these compounds, the groups given MNAN and a basal diet were switched to the experimental diets containing diosmin, hesperidin or diosmin combined with hesperidin at 1 week after the stop of MNAN injection, and maintained on these diets for 7 weeks. The other groups consisted of rats given test compounds alone or untreated rats. All animals were necropsied at the termination of the study (week 20) to determine the incidences of oesophageal neoplasms and preneoplasms, blood polyamine levels, and cell proliferation activity estimated by 5-bromodeoxyuridine (BrdU)-labelling index and by morphometric analysis of silver-stained nucleolar organizer regions' protein (AgNORs). A number of oesophageal neoplasms developed in rats treated with MNAN alone (75% and 100% incidences of carcinoma and papilloma, respectively). 'Initiation' feeding of diosmin significantly decreased the incidence of squamous cell carcinoma (P < 0.05). Also, 'initiation feeding' of both compounds singly or in combination caused a significant reduction in the multiplicities of oesophageal carcinoma and papilloma (diosmin, 78 and 58% reduction; hesperidin, 70 and 50% reduction; and the combination regimen, 70 and 30% reduction, P < 0.005). 'Post-initiation' feeding slightly decreased the multiplicities of these oesophageal neoplasms. Also, these dietary regimens reduced the multiplicities of preneoplastic lesions (hyperplasia and severe dysplasia; P < 0.05). There were no pathological alterations in rats treated with both compounds alone or the combined regimen alone or those in an untreated control group. Similarly, feeding of these compounds significantly decreased the expression of cell proliferation biomarkers (BrdU-labelling index and AgNORs number) of the non-lesional oesophageal epithelium (P < 0.05). Blood polyamine concentrations were also lowered in rats given the carcinogen and test compounds, both alone and in combination, when compared with those of rats given MNAN alone (P < 0.05). These findings suggest that diosmin and hesperidin supplementation, individually or in combination, is effective in inhibiting the development of oesophageal cancer induced by MNAN when given during the initiation phase, and such inhibition might be related to suppression of increased cell proliferation caused by MNAN in the oesophageal mucosa.

Administration, Oral↗
PubMed1997

Chemoprevention of azoxymethane-induced rat colon carcinogenesis by the naturally occurring flavonoids, diosmin and hesperidin.

The modulating effects of dietary feeding of two flavonoids, diosmin and hesperidin, both alone and in combination, during the initiation and post-initiation phases on colon carcinogenesis initiated with azoxymethane (AOM), were investigated in male F344 rats. Animals were initiated with AOM by weekly s.c. injections of 15 mg/kg body wt for 3 weeks to induced colon neoplasms. Rats were fed the diets containing diosmin (1000 ppm), hesperidin (1000 ppm) or diosmin (900 ppm) + hesperidin (100 ppm) for 5 weeks (initiation treatment) or 28 weeks (post-initiation treatment). The others contained the groups of rats treated with diosmin, hesperidin alone or in combination, and untreated. At the end of the study (32 weeks), the incidence and multiplicity of neoplasms (adenoma and adenocarcinoma) in the large intestine of rats initiated with AOM together with, or followed by, a diet containing diosmin or hesperidin were significantly smaller than those of rats given AOM alone (P <0.001). The combination regimen during the initiation and post-initiation stages also inhibited the development of colonic neoplasms, but the tumor data did not indicate any beneficial effect of diosmin and hesperidin administered together as compared with when these agents were given individually. In addition, feeding of diosmin and hesperidin, both alone and in combination, significantly inhibited the development of aberrant crypt foci. As for cell proliferation biomarkers, dietary exposure of diosmin and hesperidin significantly decreased the 5'-bromodeoxyuridine-labeling index and argyrophilic nuclear organizer region's number in crypt cells, colonic mucosal ornithine decarboxylase activity, and polyamine levels in the blood. These results indicate that diosmin and hesperidin, both alone and in combination, act as a chemopreventive agent against colon carcinogenesis, and such effects may be partly due to suppression of cell proliferation in the colonic crypts, although precise mechanisms should be clarified.

Animals↗
PubMed1997

T-cell receptor in Sjögren's syndrome.

Studies on the TCR repertoire of T cells in several inflamed lesions of SS patients have shown that there exist no unique TCR V family genes, although TCR V gene usage is relatively restricted. Analysis of the clonality of infiltrating T cells shows that some T cells expand clonally in lesions, suggesting that these cells were induced by antigen-driven rather than superantigen-driven stimulation. The restricted usage of the TCRJ beta, V alpha and J alpha genes also supports the notion that all expanded T cells do not accumulate due to superantigen. Junctional sequence analysis has revealed some conserved amino acid sequence motifs in the TCR CDR3 region, which is the antigen-binding site on T cells. These observations strongly suggest that pathogenic T cells in lesions recognize limited epitopes on autoantigens in the context of HLA. These findings are similar to TCR on T cells in rheumatoid synovium, as described elsewhere [51]. Intriguingly, T cells in lacrimal and labial salivary glands recognize common epitopes, but T cells in the kidney react with different autoantigens from those in minor salivary glands. In the future, the peptides recognized by pathogenic autoreactive T cells should be clarified to elucidate the mechanism for the progression of SS. Moreover, we predict that a vaccination with analogue peptides, to induce autoreactive T cells to anergy, might provide a new strategy for the specific treatment of SS.

Humans↗
PubMed1997

Characterisation of fibroblast-like cells in pannus lesions of patients with rheumatoid arthritis sharing properties of fibroblasts and chondrocytes.

OBJECTIVE: To better understand the characteristics of synoviocytes located in the rheumatoid arthritis (RA) pannus. METHODS: One cell line, termed PSC, was cloned from RA pannus lesions. Phenotypic analysis was done by contrast microscopy, indirect immunostaining, and safranin O staining. Transcription of several protooncogenes and matrix degrading enzymes was evaluated. The expression of mRNA for collagen II was detected by in situ hybridisation. The ability of anchorage independent growth was assessed by soft agarose culture. RESULTS: PSCs showed a high transcription of protooncogenes c-fos, c-myc and c-jun. They also expressed mRNA for matrix degrading enzymes, such as collagenase, cathepsin B, and cathepsin L. Anchorage independent growth assay demonstrated that PSCs formed colonies in soft agar culture. Phenotypic analysis showed that this fibroblast-like PSC was stained intensely with anti-vimentin and anti-fibroblast antibody. In situ reverse transcriptase assay showed that the cell line expressed type II collagen mRNA. CONCLUSION: Alternative fibroblast-like cells were identified in the pannus lesion of RA sharing properties of fibroblasts and chondrocytes. These findings suggest that this fibroblast-like cell derived from pannus lesions may contribute to the destruction of the cartilage in RA.

Aged↗
PubMed1997

In situ expression of protooncogenes and Fas/Fas ligand in rheumatoid arthritis synovium.

OBJECTIVE: To examine the relationship among the expression of protooncogenes such as c-fos and c-myc, Fas antigen, Fas ligand, and apoptosis in the synovial tissue of patients with rheumatoid arthritis (RA). METHODS: The expression of c-fos, c-myc, Fas antigen, and Fas ligand was examined in synovial tissues of 6 patients with RA and 4 with osteoarthritis (OA) using in situ reverse transcriptase (RT) assay and immunohistochemical staining. Apoptosis was detected by TUNEL method in situ. RESULTS: Expression of protooncogenes, c-fos, and c-myc was detected in all samples from patients with RA, but in only a few cells of OA synovium. 30 to 90% of cells in RA synovium positive for these protooncogenes also coexpressed Fas antigen. Fas positive cells in RA synovium underwent apoptosis to a significant degree. Fas ligand mRNA was detected only in mononuclear cells in RA synovium. CONCLUSION: The expression of protooncogenes is closely related to Fas mediated apoptosis in RA synoviocytes.

Aged↗
PubMed1997

[TCR repertoire of autoreactive T cells in autoimmune disorders].

In human autoimmune diseases such as rheumatoid arthritis, Sjögren's syndrome, and multiple sclerosis, it has been clarified that autoreactive T cells play a crucial role in the generation of autoimmune disorders. Immunohistochemical studies have shown that most infiltrating lymphocytes are CD4 positive alpha beta T cells. Recent studies with polymerase chain reaction (PCR) provides evidence about the T cell receptor (TCR) V beta and V alpha genes on their T cells. Sequence analysis of the complementarity determining region 3 (CDR3), which is a central portion for recognition of antigens by T cells, indicates some conserved amino acid motifs, supporting the notion that infiltrating T cells recognize relatively few epitopes on autoantigen.

Animals↗
PubMed1997

[An early recrudescent case of Stanford type A closing aortic dissection].

A 81-year-old female was hospitalized with chest discomfort. Findings of CT scan revealed Stanford type A acute aortic dissection, but the dissecting lumen had already closed with thrombus. Aortogram showed no intimal tear, intimal flap or ulcer like projection. Under the diagnosis of "closing aortic dissection", conservative treatment was selected. The dissecting lumen was disappearing gradually, but she had a sudden chest pain on hospital day 4 and CT scan demonstrated an enlarged and enhanced dissecting lumen. She underwent an emergency operation and a hemiarch replacement was performed successfully. Her postoperative course was uneventful and she was discharged from the hospital in good health.

Aged↗