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Biomedical subjects

S Teramoto

Publications and source records attributed to S Teramoto.

At least 37 records · Page 2Linked to original sources
PubMed2001

Isolation and purification of tyrosine hydroxylase from callus cultures of Portulaca grandiflora.

Tyrosine hydroxylase was separated from polyphenol oxidase activity and was highly purified from betacyanin producing callus cultures of Portulaca grandiflora. The purified enzyme catalyzed the formation of DOPA (L-3,4-dihydroxyphenylalanine) from tyrosine and required the pterin compounds (6-methyl-5,6,7,8-tetrahydropterin; 5,6,7,8-tetrahydrobiopterin; 6,7-dimethyl-5,6,7,8-tetrahydropterin) as coenzyme. The K(m) values for tyrosine and 6-methyl-5,6,7,8-tetrahydropterin were 0.5 mM and 0.15 mM, respectively. This enzyme was activated by Fe(2+) and Mn(2+), and inhibited by metal chelating agents.

Catalysis↗
PubMed2001

Tobacco smoke reduces viability in human lung fibroblasts: protective effect of glutathione S-transferase P1.

Cigarette smoking is thought to be a major risk factor in various lung diseases including lung cancer and emphysema. However, the direct effect of cigarette smoke on the viability of lung-derived cells has not been fully elucidated. In this study, we investigated the viability of human lung fibroblast-derived (HFL1) cells to different concentrations of cigarette smoke extract (CSE). CSE induced apoptosis at lower concentrations (10-25%) and necrosis at higher concentrations (50-100%). We also examined the effects of glutathione S-transferase P1 (GSTP1), one of the xenobiotic metabolizing and antioxidant enzymes in the lung, against the cytotoxicity of CSE. Our results indicated that the level of HFL1 cell death was decreased by transfection with a GSTP1 expression vector and was increased by GSTP1 antisense vector transfection. Therefore, transient overexpression and underexpression of GSTP1 appeared to inhibit and enhance the cytotoxic effects of CSE on HFL1 cells, suggesting that GSTP1 may have protective effects against cigarette smoke in the airway cells.

Apoptosis↗
PubMed2001

Distal airspace enlargement in the fawn-hooded rat: influences of aging and alveolar wall destruction.

BACKGROUND: A recent study has revealed that the peripheral airspace in the lungs of the fawn-hooded rat (FHR) is enlarged. However, morphological and functional factors of the FHR lung have not been fully investigated. OBJECTIVE: The purpose of our study was to examine the structural and functional changes in the FHR lung and to investigate the influence of aging on this process. Furthermore, morphological and functional measurements of the lungs of FHRs (4-48 weeks of age) were performed and the results compared with those of age-matched Wistar control rats (WCRs). METHODS: All animals were studied under controlled conditions, and morphological and functional changes of the lungs were examined. Measurements of body and lung weights were recorded, and the lungs were subjected to morphological evaluation. Morphological measurements: mean linear intercept (MLI) and destructive index were determined. Functional evaluation of the lungs: total lung capacity, pressure-volume curve, and exponential constant (K) which describes the shape of the curve were analyzed. In addition, right ventricular hypertrophy measurements were performed to assess the severity of pulmonary hypertension. Statistical analysis was performed using the unpaired t test, analysis of variance, and the Fisher post hoc test (p < 0.05). RESULTS: Morphological analysis revealed a significant increase in airspace size (MLI) in all FHRs as compared with the WCRs which was evident from an early age (4 weeks). The increase in MLI did not progress age dependently in the FHR, whereas a tendency for an age-dependent increase in MLI was observed in the WCR. The destructive index measurements revealed that the increase in MLI of FHR was not accompanied by alveolar wall destruction. Concerning the functional examination, a leftward and upward shift of the pressure-volume curve was observed in the FHRs as compared with the WCRs at all ages. As compared with the WCRs, a higher K value was observed in all FHRs which was evident from an early age (4 weeks). Age-dependent changes similar to those in MLI were observed in the K in both rat strains. CONCLUSIONS: The results of our study suggest that FHRs manifest characteristics of distal airspace enlargement accompanied by increased lung distensibility without alveolar wall destruction at an early age and that the changes do not progress age dependently. Neither an accelerated aging process nor destruction of the alveolar walls appears to be the mechanism responsible for the enlarged airspace in this rat strain.

Aging↗
PubMed2001

Association of Gc-globulin variation with susceptibility to COPD and diffuse panbronchiolitis.

Chronic obstructive pulmonary disease (COPD) and diffuse panbronchiolitis (DPB) are both characterized by chronic airflow limitation. Although the aetiology of these diseases is under investigation, it is commonly hypothesized that neutrophils have a major role in the disease pathogenesis. The variation of the genes related to chemotaxis of neutrophils may confer a risk for the development of both COPD and DPB. In the present report, the authors investigated the association between genetic variation that codes for the 416th and 420th amino acid of Gc-globulin, reported to be associated with chemotaxis of neutrophils, and susceptibility to COPD and DPB. Blood samples obtained from patients with COPD (n=63), DPB (n=82), and-control subjects (n=82) were used for the genotyping assay. The proportion of GC*1F homozygotes was significantly higher in the COPD patients than the control subjects (COPD 36.5% versus control 20.7%), and the odds ratio for GC*IF homozygotes was 2.2 (95%, confidence interval 1.1-4.6) for the COPD group. There was no difference on the distribution of the other genotypes (GC*1F-1S heterozygotes, GC*1S homozvgotes, GC*2-1F heterozygotes, GC*2-1S heterozygotes and GC*2 homozygotes) or the allele frequencies among these groups. These findings suggest that the GC*IF gene polymorphism of Gc-globulin may be one of the risk factors for chronic obstructive pulmonary disease. However, no association between this polymorphism of Gc-globulin and susceptibility to diffuse panbronchiolitis was found.

Aged↗
PubMed2001

Variables pertinent to the efficiency of adeno-associated virus (AAV) vectors mediated gene transfer to human vascular endothelial cells.

Factors influencing adeno-associated virus (AAV) - mediated gene transfer to endothelial cells are not fully determined. We tested the variables pertinent to the efficiency of AAV-mediated gene transfer to human vascular endothelial cells (HUVEC) including: (i) kinetics of transduction efficiency of LacZ gene to HUVEC, (ii) the concentration and volume of vector-containing medium, (iii) the period of incubation time of AAV vectors with HUVEC, (iv) the target cell density/proliferation, (v) the duration of transgene expression. There is a dose-response relationship between moi of vectors and transduction efficiency in HUVEC. The higher moi of AAV vectors achieved more than 80% of transduction efficiency in cultured HUVEC. AAV vectors showed incubation time dependent increase in transduction efficiency of LacZ gene to the HUVEC up to 24 h of vector exposure. The foreign gene of AAV vectors preferably transduces the lower density of cells being proliferated. These results indicate that AAV-vector is efficient for gene transfer to HUVEC, and higher moi of vectors or a longer period exposure of vectors to proliferating HUVEC can facilitate efficient tranduction of foreign gene into human vascular endothelial cells in vitro.

Cell Count↗
PubMed2001

[Effect of inhaled anticholinergic drug on pulmonary function and quality of life in elderly patients with chronic obstructive pulmonary disease].

Effects of inhaled anticholinergic drug on the physiological function of the respiratory system and quality of life (QOL) in elderly patients with chronic obstructive pulmonary disease (COPD) have not been fully elucidated. We examined the pulmonary function, static respiratory pressures, and ventilation during exercise, before and after inhalation of oxitropium bromide (OTB) in 12 male patients with COPD (mean age 82.1 +/- 0.6 years). QOL was measured with a St George's Respiratory Questionnaire (SGRQ) in the patients. Forced expiratory volume in one second was increased by the inhalation of OTB in the patients, whereas the ratio of residual volume to total lung capacity was decreased by the inhalation. Maximum inspiratory pressure was significantly increased after the administration of OTB. Dyspnea sensation during exercise measured on the Borg scale was reduced by the inhalation of OTB. The scores of SGRQ were improved by one-month treatment with OTB. These results suggest that the treatment with OTB are effective for both physiological function and several aspects of QOL in elderly patients with COPD.

Administration, Inhalation↗
PubMed2001

[Genetic variation of NADPH/NADH oxidase and susceptibility to diffuse panbronchiolitis (DPB) and chronic obstructive pulmonary disease (COPD)].

Diffuse panbronchiolitis (DPB) and chronic obstructive pulmonary disease (COPD) are both characterized by chronic airflow obstruction of unknown etiology. It is hypothesized that neutrophils play the major role in the pathogenesis of these diseases. Recent studies have suggested that genetic factors may be related to individual susceptibility to these diseases. We have investigated the association between the C 242 T polymorphism of p 22 phox, a critical subunit of superoxide-generating NADH/NADPH oxidase, and susceptibility to DPB and COPD. Blood samples obtained from both patients with DPB (n = 82), COPD (n = 53), and control subjects (n = 82) were used for this genotyping assay; and the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were performed to genotype the gene. The frequency of the C allele was 0.91, 0.92, 0.92 in the DPB, COPD, and control groups, respectively. There were no differences in the distribution of the genotype of p 22 phox among these groups, either. We concluded that there is no association between the C 242 T polymorphism of p 22 phox, and susceptibility to DPB and COPD.

Bronchiolitis↗
PubMed2001

[A case of endobronchial tuberculosis associated with bronchial asthma treated with high doses of inhaled corticosteroid].

A 46-year-old woman had been treated with 1,600-2,000 micrograms/day of beclomethasone dipropionate (BDP) and oral theophylline on the basis of a diagnosis of bronchial asthma in 1993. Eosinophilic pneumonia was diagnosed in June 1999, and she was then treated with 40 mg/day of oral prednisolone (PSL), which was gradually tapered off, and then stopped in October 1999. She was referred to our hospital because acid-fast bacilli were found in the sputum on January 18, 2000. Her chest radiographs and CT scans showed partial atelectasis of the right upper lobe, and fiberoptic bronchoscopy revealed bronchial inflammatory changes and whitish mucosal nodular lesions in the walls of the lower trachea, the right main bronchus and the orifice of the right upper lobe bronchus. She was found to have endobronchial tuberculosis. Anti-tuberculosis treatment with isoniazid, rifampicin, streptomycin and pyrazinamide was started. Serum levels of interferon-gamma were markedly elevated on admission. Asthma symptoms improved for a period of one month after the beginning of anti-tuberculosis treatment, despite the termination of inhaled corticosteroid. However, as the tuberculosis improved, the frequency and severity of the asthma increased and so corticosteroid inhalation was started again. Four months after administration of the anti-tuberculosis drug, fiberoptic bronchoscopy revealed that the endobronchial lesions had improved without any stenosis or constrictive changes. It was speculated that high doses of inhaled corticosteroid may have the potential to cause endobronchial tuberculosis whilst, ironically, at the same time preventing bronchial stenosis by endobronchial tuberculosis. This is an interesting case in which the asthma symptoms first decreased during the acute phase of endobronchial tuberculosis and then increased again after the tuberculosis improved.

Administration, Inhalation↗
PubMed2001

Abnormalities of gonadotrophs in the adenohypophysis of infertile male PD rats.

Male PD strain rats are sterile in the homozygous condition (pd/pd) due to abnormal spermatogenesis detectable at around nine weeks of age. Previous studies have indicated electron microscopic abnormalities in the Sertoli cells of pd/pd males at three and 12 weeks of age. Since spermatogenesis and Sertoli cell function depend on gonadotropins (luteinizing and follicle-stimulating hormones [LH and FSH]) and testosterone, production and/or secretion of these hormones might be altered in pd/pd males. The aim of the study reported here was to investigate the hormonal status of pd/pd males at three, six, and nine weeks of age. Although alteration was not evident in the LH-immunoreactive cells, FSH-immunoreactive cells in pd/pd males were small in size with scant cytoplasm and were reduced in number and area (73 and 51% of phenotypically normal pd/+ males, respectively) at three weeks of age, although serum FSH concentration was similar to that in pd/+ males. At six and nine weeks of age, percentages of the areas occupied by LH- and FSH-immunoreactive cells in pd/pd males were higher than those in pd/+ males. Serum FSH concentration in pd/pd males was significantly high at nine weeks of age, although a difference in serum LH and testosterone concentration was not evident. These results suggest that FSH production in pd/pd males is decreased at three weeks of age. This might be associated with the Sertoli cell abnormalities and subsequent abnormal spermatogenesis seen in adult life.

Animals↗