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S Tada

Publications and source records attributed to S Tada.

At least 181 records · Page 10Linked to original sources
PubMed1992

Site-directed mutagenesis of catalytic active-site residues of Taka-amylase A.

The cDNA encoding Taka-amylase A (EC.3.2.1.1, TAA) was isolated to identify functional amino acid residues of TAA by protein engineering. The putative catalytic active-site residues and the substrate binding residue of TAA were altered by site-directed mutagenesis: aspartic acid-206, glutamic acid-230, aspartic acid-297, and lysine-209 were replaced with asparagine or glutamic acid, glutamine or aspartic acid, asparagine or glutamic acid, and phenylalanine or arginine, respectively. Saccharomyces cerevisiae strain YPH 250 was transformed with the expression plasmids containing the altered cDNA of the TAA gene. All the transformants with an expression vector containing the altered cDNA produced mutant TAAs that cross-reacted with the TAA antibody. The mutant TAA with alteration of Asp206, Glu230, or Asp297 in the putative catalytic site had no alpha-amylase activity, while that with alteration of Lys209 in the putative binding site to Arg or Phe had reduced activity.

Amylases↗
PubMed1992

Effect of dexamethasone, dimethylsulfoxide and sodium butyrate on a human hepatoma cell line PLC/PRF/5.

The effects of agents which are known to be differentiation inducers on a human hepatoma cell line PLC/PRF/5 were investigated. Dexamethasone (DEX), sodium butyrate (SB) or dimethylsulfoxide (DMSO) were examined. They all reduced cell proliferation but differ from each other in effect on the secretion of alphafetoprotein (AFP) and hepatitis B surface antigen (HBsAg), changes in morphology and RNA transcription. SB changed the cell from polygonal into a fibroblast-like type and decreased AFP secretion. DMSO decreased the cell size and changed AFP secretion in the same manner as SB. DEX changed the cell into a larger size, as well as increased AFP secretion. HBsAg secretion and also HB virus DNA transcription was enhanced by 3 agents. AFP and myc gene transcriptions were reduced by SB but DMSO reduced only AFP. Albumin gene transcription was enhanced by SB and DEX. These results indicate that the decrease of PLC/PRF/5 proliferation is induced through different mechanisms by these 3 agents.

Butyrates↗
PubMed1992

[Studies on IFN-gamma production by peripheral blood mononuclear cells cultured with Candida antigen in asthmatics].

T-cell-derived lymphokine, IFN-gamma, has potent effects on B-cell differentiation and leukotriene C4 production in leukocytes, and inhibits the effect of IL-4 on IgE production. To investigate the role of IFN-gamma in the pathogenesis of bronchial asthma, we examined IFN-gamma production by peripheral blood mononuclear cells cultured with Candida antigen and serum Candida specific IgG1 antibody from 20 asthmatics. The results were as follows: 1) IFN-gamma production in non-atopic severe asthmatics was significantly higher than in healthy subjects, atopic mild and moderate asthmatics, and atopic severe asthmatics (p < 0.05). 2) There was a significant correlation between IFN-gamma production induced by Candida antigen and serum Candida specific IgG1 antibody (r = 0.72, p < 0.01). These results suggest that IFN-gamma may play an important role in the pathogenesis of non-atopic severe bronchial asthma.

Adult↗
PubMed1992

[A case of pulmonary infiltration with eosinophilia (PIE) syndrome induced by Saiboku-To (TJ96). Detection of ECF activity in lymphocytes stimulated with TJ96].

A case of PIE syndrome induced by Saiboku-To (TJ96) is reported. A 56-year-old woman had been treated for intractable bronchial asthma since the age of 42 years. She had a history of PIE syndrome induced by disodium cromoglycate 4 years previously (Jpn. J. Thoracic Disease, 27.1.1989). To reduce the dose of prednisolone for her asthma, administration of TJ96 was started in Dec. 1989. After 5 months of TJ96 treatment, she developed dry cough, fever, and chest pain. Physical findings and laboratory examinations revealed pulmonary infiltrations in the right lung field and severe eosinophilia. Because of suspected drug-induced PIE, TJ96 was stopped and 30 mg/day prednisolone was administered. Her symptoms and laboratory abnormalities subsequently resolved. To confirm the diagnosis of drug-induced PIE syndrome, drug-induced lymphocyte stimulation tests with TJ96 and other drugs were performed. TJ96 significantly induced lymphocyte blastogenesis with a stimulation index of 6.1. Moreover, the supernatant of the incubation mixture of TJ96 and peripheral lymphocytes from the patient showed marked eosinophil chemotactic activity. To our knowledge, there has been no previous report of PIE syndrome induced by TJ96. In addition, this is the first report of the detection of ECF activity in lymphocytes induced by an offending drug in vitro.

Asthma↗
PubMed1992

[Studies of lymphocyte activation on late asthmatic response in adult asthma].

Late asthmatic response (LAR) as well as delayed asthmatic response (DeAR) is an important clinical characteristic in adult severe asthma. These responses might be based on cell to cell interaction following lymphocyte activation. Therefore, to clarify the pathogenesis of LAR, we studied the lymphocyte functions of adult asthmatics with LAR provoked by inhalation of house dust and Candida antigen. The results revealed that mite antigen-specific lymphocyte blastogenesis, IL-2 and ECF production were significantly higher in asthmatics with LAR provoked by house dust antigen than in normal subjects and asthmatics with IAR by house dust and LAR by Candida, though there was no significant difference in NCF. Candida antigen-specific lymphocyte blastogenesis, IL-2, ECF and NCF production were significantly higher in asthmatics with LAR provoked by Candida antigen than in normal subjects and asthmatics with IAR or LAR provoked by house dust. There was a positive correlation between Candida antigen-specific IL-2 and NCF production in asthmatics with LAR provoked by Candida antigen. These results suggest that antigen-specific lymphocyte activation may play an important role in the pathogenesis of LAR, especially in asthmatics with LAR provoked by Candida antigen, and that LAR and DeAR should be considered inclusively as cell-mediated allergy.

Adolescent↗
PubMed1992

[Studies on the T-cell subset in lung tissue and BALF from patients with interstitial pneumonia].

The cellular components in bronchoalveolar lavage fluids (BALF) have been analyzed to obtain information on cellular kinetics in lung tissues of patients with diffuse pulmonary diseases. While various cells, alveolar macrophages, lymphocytes, and granulocytes appear in BALF, an increase in the percentage of lymphocytes has been noted in a variety of interstitial pneumonia. The T-cell subset of lymphocytes in BALF and biopsied lung tissues was, therefore, examined in patients with hypersensitivity pneumonitis (HP), sarcoidosis (Sar), idiopathic interstitial pneumonia (IIP) and rheumatoid arthritis with interstitial pneumonia (RA+IP) to compare the ratios of CD4/CD8 in BALF and lung tissues. The T-cell subset in BALF was analyzed by flow cytometry and the T-cell subset in lung tissues was detected with fresh frozen and thin-sliced specimens using an avidine-biotin complex (ABC) kit (Vecta Co. Ltd). The mean CD4/CD8 ratio in BALF was 0.36 in HP, 3.1 in Sar, 1.07 in IIP and 2.59 in RA+IP, while the mean CD4/CD8 ratio in lung tissues was 0.52 in HP, 2.59 in Sar, 1.11 in IIP and 2.25 in RA+IP, respectively. The ratios of CD4/CD8 in BALF and lung tissues from patients with these various interstitial pneumonia showed a positive correlation indicating that the changes of cellular components in BALF would reflect the changes in the lung tissues. Furthermore, CD4/CD8 ratios of lymphocytes infiltrating the alveolar portion and granuloma in lung tissues of HP were analyzed separately, because the CD4/CD8 ratios varied considerably from part to part of the lung tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolitis, Extrinsic Allergic↗
PubMed1992

[The cellular kinetics in BAL fluid of hypersensitivity pneumonitis and pulmonary function].

The cellular components of bronchoalveolar lavage (BAL) fluid of patients with hypersensitivity pneumonitis were analyzed in regard to the inhalation period of antigen in the environment before BAL procedure. BAL fluid in early phase of antigen inhalation contained increased percent of neutrophils as well as lymphocytes while low percent of neutrophils and prominent increase of lymphocytes in chronic antigen inhalation. Furthermore, the increased neutrophils in BAL fluid decreased rapidly after admission as cessation of antigen inhalation while the lymphocyte percent decreased gradually. In relation to respiratory function the lymphocyte percent showed statistically significant negative correlation with %TLC, %VC and %DLco. On the other hand the percent of neutrophils showed some relationship with the airway damage and inflammatory changes in early phase of this disease.

Alveolitis, Extrinsic Allergic↗
PubMed1992

[A case report of pulmonary infiltration with eosinophilia syndrome induced by Candida albicans].

A sixty six-year-old female who had been treated for bronchial asthma for about 25 years was admitted to the hospital with complaints of episodes of dyspnea, eosinophilia and infiltrative shadows in the chest X-ray film. An infiltrative shadow appeared to move from the left to the right lung field and finally formed a shadow of atelectasis in the middle field of the right lung. A sputum culture showed only Candida albicans. Allergic and immunologic examination revealed high IgE serum levels with specific IgE against Candida albicans in high titer, and Aspergillus fumigatus in low titer. The precipitating antibody was shown only against Candida antigen. Additionally, the blastogenic response to Candida antigen was high in comparison with other fungal antigens including Aspergillus fumigatus. The clinical features and laboratory findings of this patient were found to satisfy Rosenberg's criteria for allergic bronchopulmonary aspergillosis (ABPA), except for the existence of Candida albicans in place of Aspergillus species as the causative antigen. The pathogenesis of PIE syndrome has been studied and various allergic mechanisms against many antigens reported. In this patient Candida albicans could be playing the crucial role in the formation of PIE syndrome, which might be best described as allergic bronchopulmonary candidiasis (ABPC).

Aged↗
PubMed1992

[The significance of soluble IL-2 receptors in rheumatoid arthritis with interstitial pneumonia].

Interstitial pneumonia is well known as one of the complications of rheumatoid arthritis (RA). While interleukin-2 (IL-2) regulates the immune response through IL-2 receptor (IL-2R), the exact role of the soluble form of IL-2R (sIL-2R), recognized as a part of the alpha chain or IL-2R, is still obscure. So, the immunological significance of sIL-2R in serum and in bronchoalveolar lavage fluid (BALF) of those of RA patients with or without interstitial pneumonia was studied. The sIL-2R was measured with an ELISA kit (T-Cell Science Ltd). The levels of sIL-2R in the sera of RA patients without interstitial pneumonia were significantly higher than those of normal controls. Furthermore, the levels of sIL-2R showed a statistically significant correlation with ESR and Lansbary's index. The levels of sIL-2R of RA patients with interstitial pneumonia were higher than in those without interstitial pneumonia although the evaluation of class and stage of arthritis in those RA patients with or without interstitial pneumonia revealed no significant difference. A high sIL-2R/albumin ratio in BALF of RA patients with interstitial pneumonia was shown in comparison with those of normal control. These data indicate that the estimation of sIL-2R in RA patients could be useful in estimating the disease activity and that high levels of sIL-2R reflect the active immune response in the lungs of RA patients with interstitial pneumonia.

Arthritis, Rheumatoid↗
PubMed1992

[Asthma classification by score calculated from clinical findings and examinations. Comparison between clinical diagnosis and score diagnosis].

Asthma classification by clinical symptoms and signs (clinical diagnosis) was compared with the classification by score calculated from clinical findings and examinations (score diagnosis) in 25 patients with bronchial asthma. 1. Ten subjects classified as Ia (simple bronchoconstriction type) by clinical diagnosis were divided into 6 cases with expectoration of less than 49 ml a day and 4 cases with expectoration of between 50 and 99 ml. The level of serum IgE and number of eosinophils in BALF were significantly higher in the latter cases than in the former cases. The cases whose expectoration was from 50 to 99 ml a day were classified as Ib (bronchoconstriction with hypersecretion type) by score diagnosis. 2. The six subjects who were classified as type Ib by clinical diagnosis were also evaluated as type Ib by score diagnosis. 3. Nine of the 10 subjects classified as type II by clinical diagnosis were evaluated as type II by score diagnosis. One case, whose score was under 12 points, was evaluated as questionable type II by score diagnosis.

Adult↗
PubMed1992

Mutagenicity of the new quinolone antibacterial agent levofloxacin.

UNLABELLED: A new quinolone antibacterial agent (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10- (4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3-de][1,4]benzoxazine-6- carboxylic acid hemihydrate (levofloxacin, DR-3355, CAS 100986-85-4), was studied for mutagenicity using the following short-term in vitro and in vivo tests. 1. IN VITRO STUDIES: reverse mutation test (Ames method) on S. typhimurium and E. coli; and HGPRT forward mutation test, cytogenetic test, and sister chromatid exchange (SCE) test, all on Chinese hamster cells. 2. In vivo studies: mouse micronucleus test, SCE test on mouse bone marrow cell, in vivo-in vitro unscheduled DNA synthesis (UDS) test on rat primary hepatocytes, and dominant lethal test in BDF1 mice. In the in vitro tests for SCE and for chromosomal aberration, DR-3355 gave dose-dependent positive responses, but no mutagenicity was observed in the same indicators of the in vivo studies, even at the maximum tolerated doses. This strongly suggested that DR-3355 would have no mutagenic effects when used in the treatment of infectious diseases. DR-3355 did not show any positive response in the reverse mutation test, the HGPRT mutation test, the in vivo-in vitro UDS test or the dominant lethal test. These results suggest that chemotherapy with DR-3355 should have no mutagenic effect in man.

Animals↗
PubMed1991

Structural and functional conservation of histidinol dehydrogenase between plants and microbes.

The partial amino acid sequence of histidinol dehydrogenase (L-histidinol:NAD+ oxidoreductase, EC 1.1.1.23) from cabbage was determined from peptide fragments of the purified protein. The relative positions of these peptides were deduced by aligning their sequences with the sequence of the HIS4C gene product of Saccharomyces cerevisiae. cDNA encoding histidinol dehydrogenase was then amplified from a library using a polymerase chain reaction primed with degenerate oligonucleotide pools of known position and orientation. By using this amplified fragment as a probe, an apparently full-length cDNA clone was isolated that is predicted to encode a proenzyme having a putative 31-amino acid chloroplast transit peptide and a mature molecular mass of 47.5 kDa. The predicted protein sequence was 51% identical to the yeast enzyme and 49% identical to the Escherichia coli enzyme. Expression of the cDNA clone in an E. coli his operon deletion strain rendered the mutant able to grow in the presence of histidinol.

Alcohol Oxidoreductases↗
PubMed1991

Construction of a fusion gene comprising the Taka-amylase A promoter and the Escherichia coli beta-glucuronidase gene and analysis of its expression in Aspergillus oryzae.

Northern blot analysis of glucose-grown and starch-grown mycelia of Aspergillus oryzae RIB40 was conducted using the cloned Taka-amylase A (TAA) gene as a probe. The amount of mRNA homologous to the TAA gene was increased when this fungus was grown with starch as a sole carbon source. In order to analyze the induction mechanism, we inserted the Escherichia coli uidA gene encoding beta-glucuronidase (GUS) down-stream of the TAA promoter and introduced the resultant fusion gene into the A. oryzae genome. Production of a functional GUS protein was induced by starch, but not by glucose. When the effects of various sugars on expression of the fusion gene were examined, the results suggested that the expression of the fusion gene was under control of the TAA gene promoter.

Aspergillus oryzae↗
PubMed1991

MR imaging of adrenoleukodystrophy.

We performed MRI in 7 cases with adrenoleukodystrophy (ALD), including 3 cases with childhood ALD, 3 cases with adrenomyeloneuropathy (AMN) and one symptomatic heterozygote. The symptomatic heterozygote was the mother of the patient with AMN. High-field-strength (2.0T) MRI was used in two cases with childhood ALD. In all 3 cases of childhood ALD, MR showed widespread lesions in both cerebral hemispheres. Areas of low intensity in the diencephalon or striatum on heavily T2-weighted images at 2.0T were seen in 2 cases with childhood ALD. Cerebral lesions confined to the internal capsule, cerebral peduncle and optic radiation in the adult onset ALD including AMN and symptomatic heterozygote, have not been reported and this confinement may indicate an early stage of the disease.

Adrenoleukodystrophy↗
PubMed1991

Double-contrast radiographic features in primary small intestinal lymphoma of the 'western' type: correlation with pathological findings.

Eighteen patients with 20 primary lesions of small intestinal lymphoma of the 'Western' type were examined to determine the double-contrast radiographic features of the disease with pathological correlation. The radiographic appearances on double-contrast study were divided into five groups: polypoid (3 lesions), stricturing (6), non-stricturing (3), aneurysmal (3), and intussusception (5). In the first four groups, ulceration, signs of submucosal tumour, and displacement of adjacent loops were frequent. Two early lesions confined to the submucosal layer were also seen. There was a close association between the radiographic appearance and macroscopic findings of the resected specimens, including the cross section of the tumour, but no correlation with the cell type. These results indicate that the double-contrast study accurately reflects the morphological changes of primary small intestinal lymphoma.

Adolescent↗
PubMed1991

Amyloidosis of the small intestine: findings on double-contrast radiographs.

The appearance of the small intestinal mucosa on double-contrast barium examinations was studied in 26 patients with proved intestinal amyloidosis. Findings included innumerable fine granular densities 1-3 mm in diameter (16 patients), multiple nodular densities 3-4 mm in diameter (four patients), multiple polypoid protrusions 4-10 mm in diameter (three patients), irregularities of Kerckring folds (12 patients), and multiple erosions (eight patients). The multiple nodular densities and erosions disappeared after the patients were treated with total parenteral nutrition. The other abnormalities remained unchanged on follow-up examinations. Our results indicate that double-contrast radiographic findings of the small intestine in patients with amyloidosis include mucosal abnormalities that vary according to the pathologic type of amyloid deposition.

Amyloidosis↗