Biomedical subjects

A Suwa

Publications and source records attributed to A Suwa.

At least 37 records · Page 2Linked to original sources

PubMed1997

[An autopsy case of anti-neutrophil cytoplasmic antibodies associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma].

Here we report an autopsy case with anti-neutrophil antibodies (ANCA) associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma. A 69-year-old woman was admitted to Tokyo Metropolitan Ohtsuka Hospital in October 1995 because of leg edema. She had presented cough in 1990 and diagnosed as interstitial pneumonia, esophageal varices and liver chirosis. On admission, laboratory data showed mild anemia, hypoproteinemia, and marked gammagloblinemia. IgM-HA antibody, HBs antigen, HBs antibody, HCV antibody and HDV antibody were negative. Anti-nuclear antibody, anticentromere antibody, anti-neutrophil cytoplasmic antibody against myeloperoxidase and cathepsin G (MPO-ANCA and cathepsin G), rheumatoid factor and direct coombs test were positive. Serum level of AFP and CEA were elevated. Ultrasonography and computed tomography of abdomen scowed liver chirosis and tumor in left lobe of liver. The diagnosis of liver chirosis based on autoimmune hepatitis and Interstitial pneumonia was made with clinical course, laboratory findings and radiographic findings although liver biopsy was not performed. She complained of bloody stool due to ulcer of the large intestine, and died of liver failure which progressed rapidly. The autopsy findings detected that pulmonary fibrosis, liver fibrosis with multiple hepatocellular carcinoma, necrotizing crescentic glomerulonephritis, and vasculitis of small artery inn colon. This was the first report of MPO-ANCA associated vasuculitis complicated with autoimmune hepatitis and hepatocellular carcinoma. Clinical significance of ANCA and immunogenetic background of these diseases were discussed.

Aged↗

PubMed1997

[An adult case of dermatomyositis complicated with cecum perforation and panniculitis].

The case of dermatomyositis complicated with cecum perforation and panniculitis occurred in a 62-year-old woman was reported. She was admitted to Keio University Hospital with a history of proximal muscular weakness, and dysphagia. Physical examination showed erythema over the face and shoulder. Serum level of muscle enzymes was remarkably increased. The diagnosis of dermatomyositis was made based on proximal muscular weakness, elevated serum level of muscle enzymes and myogenic change of electromyocardiogram. The treatment with 60 mg/day of prednisolone was started, and was a good response. However, 7 months later the disease became active again when the amount of prednisolone was reduced to 13 mg/day. Subsequently she complained of abdominal pain on the right lower quadrant. The surgical findings included peritonitis due to the perforation of the cecum and multiple ulcers of the cecum. After operation, azathioprine was added. Four years and 9 months later, she noticed skin erythema with ulceration and subcutaneous nodule. Skin biopsy indicated the findings of the panniculitis with membrano-cystic lesion. It was thought that both cecum perforation and panniculitis were caused by angiopathy which was often seen in childhood dermatomyositis.

Cecal Diseases↗

PubMed1997

[A case of microscopic polyangitis accompanied by hearing loss as the initial sign of the disease].

Here we report a case of microscopic polyangitis (MPA) with anti-neutrophil cytoplasmic antibodies against myeloperoxidase (MPO-ANCA) accompanied by perceptive dominant hearing loss as the initial sign of the disease. A 52-year-old woman was admitted to Tokyo Metropolitan Ohtsuka Hospital in April 1996 because of bilateral progressive hearing loss. On admission, she had presented bilateral perceptive hearing loss, fever, myalgia, and weight loss. Laboratory data showed accelerated erythrocyte sedimentation rate, proteinuria, microscopic hematuria, leukocytosis, hypoproteinemia, and elevated creatinine level. Serum level of MPO-ANCA was elevated. Chest X-ray and computed tomography showed mild pleural effusion and interstitial shadow in bilateral lung fields. The biopsy findings detected that focal glomerulonephritis, and necrotizing angitis of small artery in kidney. The diagnosis of MPA was made with clinical course, laboratory findings, radiographic findings, and biopsy finding. Treatment was initiated with 45 mg of prednisolone, followed by marked improvement of hearing loss and decreased titer of serum MPO-ANCA. There are only seven reports showing hearing loss as the initial sign of the disease occurred in polyarteritis nodosa and MPA. The present case suggests the possibility that hearing loss may be the symptom of MPO-ANCA associated vasculitis.

Anti-Inflammatory Agents↗

PubMed1996

CPP32/Yama/apopain cleaves the catalytic component of DNA-dependent protein kinase in the holoenzyme.

DNA-dependent protein kinase (DNA-PK) is composed of a 460-kDa catalytic component (p460) and a DNA-binding component Ku protein. Immunoblot analysis after treatment of Jurkat cells with anti-Fas antibody demonstrated the cleavage of p460 concomitantly with an increase in CPP32/Yama/apopain activity. Recombinant CPP32/Yama/apopain specifically cleaved p460 in the DNA-PK preparation that had been purified from Raji cells into 230- and 160-kDa polypeptides, the latter of which was detected in anti-Fas-treated Jurkat cells. The regulatory component Ku protein was not significantly affected by CPP32/Yama/apopain. DNA-PK activity was decreased with the disappearance of p460 in the incubation of DNA-PK with CPP32/Yama/apopain. These results suggest that the catalytic component of DNA-PK is one of the target proteins for CPP32/Yama/apopain in Fas-mediated apoptosis.

Amino Acid Sequence↗

PubMed1996

The interaction between Ku antigen and REF1 protein mediates negative gene regulation by extracellular calcium.

Through the specific binding of a negative calcium-responsive element to its binding protein in response to extracellular Ca (Ca2+e), negative calcium-responsive element-bearing genes, such as the human parathyroid hormone gene, are negatively regulated by Ca2+e. The Ku antigen mediated negative gene regulation by Ca2+e by interacting with a redox factor protein, REF1. Although sequence-nonspecific DNA binding activity of the Ku antigen has been well characterized, the mechanism of its sequence-specific DNA binding remained obscure. Here, we report that the specific binding of the Ku antigen to another protein, REF1, leads to DNA-protein complex formation with a novel sequence specificity and thereby regulates gene expression.

Amino Acid Sequence↗

PubMed1996

Autoantibodies to DNA-dependent protein kinase. Probes for the catalytic subunit.

DNA-dependent protein kinase (DNA-PK) is an important nuclear enzyme which consists of a catalytic subunit known as DNA-PKcs and a regulatory component identified as the Ku autoantigen. In the present study, we surveyed 312 patients in a search for this specificity. 10 sera immunoprecipitated a large polypeptide which exactly comigrated with DNA-PKcs in SDS-PAGE. Immunoblot analysis demonstrated that this polypeptide was recognizable by a rabbit antiserum specific for DNA-PKcs. Although the patient sera did not bind to biochemically purified DNA-PKcs in immunoblots or ELISA, they were able to deplete DNA-PK catalytic activity from extracts of HeLa cells in a dose-dependent manner. We conclude that these antibodies should be useful probes for studies which aim to define the role of DNA-PK in cells. Since six sera simultaneously contained antibodies to the Ku protein, these studies suggest that relatively intact forms of DNA-PK complex act as autoantigenic particles in selected patients.

Antigens, Nuclear↗

PubMed1996

Autoantibodies to glycyl-transfer RNA synthetase in myositis. Association with dermatomyositis and immunologic heterogeneity.

OBJECTIVE: To elucidate the clinical significance and immunologic heterogeneity of anti-glycyl-transfer RNA (tRNA) synthetase antibodies in polymyositis/dermatomyositis (PM/DM). METHODS: Sera from 345 patients with rheumatic diseases, including 91 with myositis, were examined using immunoprecipitation assays. Autoantibodies to aminoacyl-tRNA synthetases were further analyzed with 2-dimensional RNA fractionation and via inhibition of in vitro aminoacylation. RESULTS: Serum from 1 patient with DM and interstitial lung disease immunoprecipitated glycyl-tRNA synthase along with only 1 of 4 associated tRNAs, in comparison with control anti-glycyl-tRNA synthetase antibodies, which bound the enzyme along with all 4 associated tRNAs. Immunoblotting findings and a lack of in vitro inhibition aminoacylation of tRNA(gly) by serum from this patient also suggested differences between the epitope specificity of this serum and that of other sera with anti-glycyl-tRNA synthetase antibodies. CONCLUSION: This identification of antibodies to glycyl-tRNA synthetase from a patient with DM underscores the association of this specificity with the disease. The finding that these antibodies bound an epitope outside the active site of the synthetase enzyme, in contrast to most anti-aminoacyl-tRNA synthetases, emphasizes the immunologic heterogeneity of these autoantibodies.

Antibody Specificity↗

PubMed1996

Autoimmunity to RNA polymerase II is focused at the carboxyl terminal domain of the large subunit.

OBJECTIVE: Previous studies have demonstrated antibodies to the large (220 kd) polypeptide subunit of RNA polymerase II (Pol II) in sera from certain patients with scleroderma. In the present study, we sought to identify the autoantigenic region on this polypeptide. METHODS: A recombinant fusion protein, corresponding to the 52-heptapeptide repeat found in the carboxyl terminal domain (CTD) of the large Pol II subunit, was used to identify 15 patient sera that contained autoantibodies. Synthetic peptides CTD7 (representing a single heptapeptide) and CTD18 (representing 2 1/2 heptapeptide repeats) were used in a competitive inhibition assay to define the specificity of these sera and the importance of the CTD as an autoantigen. RESULTS: All 15 sera immunoprecipitated the Pol II subunit from radiolabeled cell extracts, and 11 of them bound the CTD fusion protein in immunoblots. Immunoprecipitation of Pol II was completely inhibited by CTD18 in 5 sera and partially inhibited in 4 additional sera. CONCLUSION: These results indicate that the CTD heptapeptide repeat is a focal point for autoimmune responses in scleroderma. It is likely that the repetitive sequence and high content of charged residues of this structure contribute to its role as an autoantigen.

Adult↗

PubMed1996

[A case of systemic sclerosis associated with interstitial pneumonia with various autoantibodies: improvement by intravenous cyclophosphamide therapy].

A 41-year-old woman was admitted to Tokyo Women's Medical College Aoyama Hospital in January 1994. She presented cough and dyspnea in September 1991. The diagnosis of interstitial pneumonia was made based on TBLB. Interstitial pneumonia was responsive to initial prednisolone of 40 mg daily. When dose of prednisolone was reduced to 15 mg daily, she complained of cough and dyspnea again. She was referred to Institute of Rheumatology, Tokyo Women's Maedical College in November 1993. She was diagnosed as systemic sclerosis associated with interstitial pneumonia based on proximal scleroderma and digital pitting scar. Double immunodiffusion and immunoprecipitation assay revealed the presence of anti-Ki, anti-Wa, and anti-RNA polymerases antibodies in the serum. On admission in March 1994, she was treated with intravenous cyclophosphamide therapy at 500 mg/day once a mouth. After the third infusion, respiratory symptoms, pulmonary function test values, findings of chest X-ray and CT scan were improved without adverse drug effects. Intravenous cyclophosphamide therapy seems to be useful in this case. The efficacy of Intravenous cyclophosphamide therapy in the treatment of the interstitial pneumonia associated with systemic sclerosis was discussed.

Adult↗

PubMed1996

[Two cases of interstitial pneumonia with anti-PL-12 (alanyl tRNA synthetase) antibodies].

We present two cases of interstitial pneumonia (IP) whose sera contain autoantibodies to PL-12 (alanyl tRNA synthetase). The first patient is a 47-year-old female who was diagnosed as IP and treated with corticosteroid at another hospital. She was admitted to Keio University Hospital due to worsening of dyspnea and polyarthritis. Laboratory studies revealed elevation of LDH and CRP, and her chest radiography showed interstitial fibrosis. Because of clinical deterioration, the dose of corticosteroid was increased (prednisolone 40 mg/day) and her symptom was stabilized. The second patient, a 55 year-old female, was admitted to Tokyo Metropolitan Ohtsuka Hospital because of dyspnea on exertion and polyarthritis. She did not show any symptom of myositis and was diagnosed as IP with arthritis on the basis of her clinical and chest radiography. She was treated with oral corticosteroid (prednisolone 30 mg/day), which resulted in improvement of her respiratory symptom and arthritis. Both patients were found to have autoantibodies to the PL-12. Autoantibodies to aminoacyl tRNA synthetases have been recognized as having a linkage with myositis mainly because of observations of the Jo-1 specificity. There was one report on a North American population that most but not all patients with anti-PL-12 antibodies had myositis. However, the clinical significance of anti-PL-12 has not been examined in Japanese patients. These patients suggested that anti-PL-12 antibodies have a stronger association with IP than myositis in Japanese patients.

Alanine-tRNA Ligase↗

PubMed1995

Identification of human autoantibodies to transcription factor IIB.

We have characterized the ability of various human autoimmune sera to react with RNA polymerase II transcription factors. One serum, which strongly inhibited transcription in a cell-free system, was shown to contain antibodies directed against human TFIIB. The serum did not show reactivity against the other general transcription factors, including human TBP, TFIIE and TFIIF. The inhibition of transcription was directly attributable to depletion of TFIIB activity, as demonstrated by reconstitution of activity with recombinant TFIIB. It has long been recognized that components of the RNA processing machinery are major human autoantigens. The present results show that at least one general transcription factor required for messenger RNA synthesis is an autoantigen as well.

Antibody Specificity↗

PubMed1995

[A case of rheumatoid arthritis complicated with salazosulfapyridine-induced aplastic anemia].

A 64 year-old woman with rheumatoid arthritis was admitted to our hospital because of general fatigue. She noticed polyarthralgia 8 months prior to the admission and diagnosis of rheumatoid arthritis was made. Administration of salazosulfapyridine (1.0 g/day) was started 6 months before the admission. Complete remission of rheumatoid arthritis was obtained in 2 months and blood cell counts showed normal values at that time. The results of laboratory tests included hemoglobin; 8.6 g/dl, white blood cell count; 1,900/mm3 with a differential of 19% neutrophils, 77% lymphocytes, and 4% monocytes; platelets were 21,000/mm3. A bone marrow aspiration and biopsy were performed. There were reduced numbers of myelocytes, erythroblasts, and megakaryocytes indicating aplastic anemia. Salazosulfapyridine was discontinued. Prednisolone, anabolic steroid and granulocyte-colony stimulating factor (G-CSF) were administrated. In spite of these therapy, recovery of peripheral blood cell counts have not been observed and supporting therapy including red cell and platelets transfusion have been continued. To our knowledge, this is the first case report which describes occurrence of aplastic anemia in patients with rheumatoid arthritis treated by salazosulfapyridine.

Anemia, Aplastic↗

PubMed1995

[A case of adult onset Still's disease complicated with adult respiratory distress syndrome and disseminated intravascular coagulation].

A 71 year-old man with adult onset Still's disease was admitted to our hospital because of fever, sore throat, myalgia and macular nonpruritic salmon pink eruption. He was treated with prednisolone, 40 mg daily and these symptoms disappeared. When the dose of prednisolone was reduced to 30 mg daily, he began to notice fever. 5 days later he developed adult respiratory distress syndrome (ARDS). The dose of prednisolone was increased to 50 mg daily and oxygen administration was started. All symptoms began to improve immediately and the dose of prednisolone was decreased to 40 mg daily. 10 days later he noticed fever and skin rash. Laboratory investigation showed platelet counts of 69,000/mm3, a ferritin of 37,000 ng/ml, and increased fibrinogen degradation product, indicating increased activity of adult onset Still's disease associated with disseminated intravascular coagulation (DIC). The dose of prednisolone was again increased to 60 mg daily, and 100 mg of nafamostat mesilate was administrated intravenously. All above symptoms associated with adult onset Still's disease and DIC disappeared. The dose of prednisolone was gradually decreased and the clinical course was uneventful with daily administration of 10 mg of prednisolone. Although there are a couple of case report which described the association of adult onset Still's disease with either ARDS or DIC, the association of adult onset Still's disease with both ARDS and DIC have not been reported yet.

Aged↗

PubMed1995

[A case of Sjögren's syndrome and systemic lupus erythematosus complicated with necrotizing angiitis of the gallbladder].

A 71 year-old man with Sjogren's syndrome and systemic lupus erythematosus was admitted to our hospital because of abdominal pain and fever. Laboratory investigation showed an ESR of 76 mm/hr, elevation of CRP and marked leukocytosis. Abdominal ultrasound and CT scan showed enlargement of the gallbladder and intravesicular sludge without stones. With a clinical diagnosis of acute cholecystitis and pan-peritonitis, the surgical procedures including cholecystectomy were performed. Histological examination of the gallbladder showed a presence of necrotizing angiitis of small arteries. The postoperative course was uneventful with daily administration of 10 mg of prednisolone.

Acute Disease↗

PubMed1995

[Interstitial lung disease in patients with connective tissue diseases].

Interstitial lung disease is a significant prognostic factor in connective tissue diseases. To further clarify clinical and immunological features of interstitial lung disease, we studied 894 consecutive patients with connective tissue diseases first evaluated between 1970 and 1993. Interstitial lung disease was found in 101 of 181 (56%) patients with systemic sclerosis, 92 of 183 (50%) with overlap syndrome, 35 of 76 (46%) with polymyositis/dermatomyositis, and 13 of 444 (3%) with systemic lupus erythematosus (p < 0.05, systemic lupus erythematosus vs. other connective tissue diseases). The presence of interstitial lung disease correlated with decreased survival in systemic sclerosis and in polymyositis/dermatomyositis, but not in overlap syndrome or in systemic lupus erythematosus. Interstitial lung disease in patients with connective tissue diseases was classified into two types: acute (n = 8) and chronic (n = 233). Among the 8 patients with acute disease, 4 (all with dermatomyositis) died of respiratory failure and 3 (all with systemic lupus erythematosus) responded to corticosteroids. Among the 233 patients with chronic interstitial lung disease, 20 had polymyositis/dermatomyositis with anti-aminoacyl tRNA synthetase antibodies and 40 had overlap syndrome with anti-U1 RNP antibodies. Respiratory failure in these patients was not frequent and occurred late in the course of the disease. As a cause of death, respiratory failure was associated with autoantibodies to topoisomerase I and aminoacyl tRNA synthetase but not anti-U1 RNP. Autoantibodies to aminoacyl tRNA synthetases were detected before the development of interstitial lung disease in 9 patients with polymyositis/dermatomyositis. We conclude that the clinical features of interstitial lung disease associated with connective tissue diseases vary with the type of connective tissue disease, and that analysis of autoantibodies can be useful in establishing a diagnosis and in forecasting the course and outcome.

Adult↗

PubMed1994

DNA-dependent protein kinase (Ku protein-p350 complex) assembles on double-stranded DNA.

The Ku protein is an autoantigen that consists of 70- and 80-kDa polypeptides. It associates with double-stranded DNA at free ends. In the present study, we examined the ability of anti-Ku antibodies to immunoprecipitate various structures from extracts of HeLa cells prepared at different salt concentrations. Under physiological conditions, these antibodies identified a complex containing the Ku protein and the 350-kDa component (p350) of DNA-dependent protein kinase (DNA-PK), which appeared to be closely associated on the DNA strand. In reconstitution experiments with cell extracts and biochemically purified components, the Ku protein-p350 complex formed only in the presence of double-stranded DNA. The reconstituted complex was catalytically active. Together with previous studies, these results indicate that the Ku protein interacts with DNA to create a binding site for p350 as the DNA-PK holoenzyme assembles.

Antigens, Nuclear↗

PubMed1994

Characterization of the Su antigen, a macromolecular complex of 100/102 and 200-kDa proteins recognized by autoantibodies in systemic rheumatic diseases.

The Su autoantigen was characterized biochemically using human and murine autoimmune sera and the clinical significance of anti-Su antibodies was studied in 236 Japanese and 160 American patients with systemic rheumatic diseases. Anti-Su in immunodiffusion (ID) was strongly associated with immunoprecipitation of one or more 100- to 102-kDa proteins by MRL/lpr mouse sera (27/32 of ID positive vs 4/20 of ID negative, P = 0.000016), and all four human anti-Su reference sera immunoprecipitated the 100/102-kDa protein(s). In addition, all sera immunoprecipitated a less efficiently labeled approximately 200-kDa protein that comigrated on sucrose density gradients with the 100/102-kDa proteins. Based on these data, a complex of the 100/102-kDa and 200-kDa proteins is likely to be the main target of anti-Su antibodies. Three of four anti-Su monospecific sera were negative for immunofluorescent antinuclear antibodies (ANA), suggesting anti-Su antibodies may be associated with a negative ANA in some cases. Autoantibodies to Su were detected frequently by immunoprecipitation in systemic lupus erythematosus (17-21%), scleroderma (13-20%), and overlap syndrome (22-40%) and were associated with autoantibodies to Ku.

Animals↗

PubMed1994

[Study on combined of auranofin, salazosulfapyridine and methotrexate in rheumatoid arthritis].

Patients with rheumatoid arthritis who did not respond sufficiently to auranofin therapy were divided into three groups to be continued on auranofin monotherapy (1), to be on combination therapy of auranofin and salazosulfapyridine (2) and to be given methotrexate concomitantly with auranofin (3), and clinical responses were compared in a prospective manner. Patients on combination therapy either with salazosulfapyridine or with methotrexate demonstrated higher improvement than those on continued auranofin monotherapy. No unknown side effects associated with monotherapy of any of the three compounds were seen in any of the three groups. The study suggests usefulness of combination therapy either with methotrexate or with salazosulfapyridine for patients who failed to respond sufficiently to auranofin.

Adult↗