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T Miyagawa

Publications and source records attributed to T Miyagawa.

At least 19 recordsLinked to original sources
PubMed1995

Mutated yeast heat shock transcription factor exhibits elevated basal transcriptional activation and confers metal resistance.

Cadmium-resistant Saccharomyces cerevisiae strain 301N exhibits high basal as well as cadmium-induced expression of the CUP1 metallothionein gene. Since regulation of CUP1 is usually restricted to copper ions, our goal was to identify the factor responsible for the high metallothionein levels in strain 301N. The gene responsible for the observed phenotype is a spontaneously mutated heat shock transcription factor gene (HSF1). A double, semidominant HSF1 mutant with substitutions at codons 206 and 256 within the DNA-binding domain of the heat shock factor (HSF) confers two phenotypes. The first phenotype is elevated transcriptional activity of the HSF mutant (HSF301), which results in constitutive thermotolerance. A second HSF301 phenotype is enhanced binding affinity for the heat shock element (HSE) within the CUP1 5'-sequences, resulting in high basal transcription of metallothionein. The CUP1 HSE is a minimal heat shock element containing only two perfectly spaced inverted repeats of the basic nGAAn block. Cells containing HSF301 are resistant to cadmium salts. The single R206S mutation is responsible for the high affinity binding to the CUP1 HSE. In addition, the R206S HSF substitution exhibits constitutive transcriptional activation from a consensus HSE (HSE2). The F256Y substitution in HSF attenuates the effects of R206S on the consensus HSE2, but not on the CUP1 HSE.

Base Sequence↗
PubMed1995

Effects of upper limb exercise on thermoregulatory responses in patients with spinal cord injury.

We evaluated changes in body temperature, heart rate, and oxygen uptake during arm cranking exercise (20 watts, 30 min) in an artificial climate room at a temperature of about 25 degrees C or 35 degrees C (relative humidity, about 50%) in 5 patients with paraplegics due to spinal cord injury (SCI). The tympanic temperature (Tty) was significantly higher from rest to recovery at 35 degrees C than at 25 degrees C. The mean Tty after 10 minutes of rest was 36.68 degrees C +/- 0.396 (mean +/- SD) at a room temperature of 25 degrees C and 37.25 degrees C +/- 0.253 at 35 degrees C, showing a difference of about 0.5 degrees C. This difference was maintained during exercise and recovery. The Tty at the end of exercise was higher than that at the start of exercise by 0.66 degrees C +/- 0.218 (mean +/- SD) at 25 degrees C and by 0.59 degrees C +/- 0.210 at 35 degrees C. The skin temperature (Tsk) in each measurement area (the head, arm, chest, thigh, shin, and calf) was significantly higher at 35 degrees C. Oxygen uptake did not differ between 25 degrees C and 35 degrees C. The heart rate was significantly higher at 35 degrees C than at 25 degrees C during rest and at the start of exercise but did not differ during exercise and recovery. Thus, mild-moderate exercise in this study did not cause marked changes such as increases in body temperature and heart rate that affect biological function in SCI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Pulmonary complications in patients with rheumatoid arthritis].

Pulmonary manifestations of rheumatoid arthritis were studied in 26 patients. Pulmonary complications could be divided into four subgroups: Interstitial pneumonia/Pulmonary fibrosis (n = 18), Bronchiolitis Obliterans Organizing Pneumonia (n = 4), Bronchiolitis Obliterans (n = 2), and Pleuritis/Pericarditis (n = 1). Analysis of cells in broncho-alveolar lavage fluid (BALF) revealed abnormally high percentages of lymphocytes in one-half of the patients and abnormally high percentages of neutrophils in one-third of the patients. The percent of BALF cells that were neutrophils was higher with higher chest radiograph grades. Analysis of soluble constituents of BALF indicated local production of IgG in two cases, but IgM-rheumatic factor was not detected. In 18 of 26 patients corticosteroid or immunosuppressive drugs were needed, and most of the patients responded to the therapy and had good outcomes. The conditions of 6 patients with interstitial pneumonia/pulmonary fibrosis deteriorated and 4 patients died of progressive respiratory failure. The subclassification of rheumatoid lung was useful for predicting its outcome.

Aged↗
PubMed1994

Immunohistochemical investigation of epidermal growth factor receptor expression in ameloblastomas.

Immunohistochemical analysis was performed to determine the localization of epidermal growth factor receptor (EGFR) in ameloblastomas. Ameloblastoma samples were classified into follicular, plexiform, and basal cell types. The number of cases in each category was 17, 19 and 3, respectively. Ameloblastomas, disregarding their histological type, consist of two cell forms: peripheral columnar cells and central stellate cells. The frequency of EGFR expression was much higher in the latter than in the former (P < 0.005). On analysis with respect to histological types, the frequency of EGFR expression in columnar cells was not significantly different between the follicular and the plexiform types, but was observed more frequently in the stellate cells in the follicular than in the plexiform ameloblastomas (P < 0.05). This pattern of EGFR expression was not consistent with the PCNA staining pattern, but was similar to that of keratin expression which we have reported previously. The present study suggests that EGFR expression in ameloblastomas is closely associated with tumour differentiation, and squamous differentiation in particular.

Ameloblastoma↗
PubMed1994

A novel POU domain gene, zebrafish pou2: expression and roles of two alternatively spliced twin products in early development.

POU domain proteins are a large family of transcriptional regulatory proteins, many of which are implicated in the control of gene expression during early development. We describe here the cloning and expression of zebrafish pou2, a novel POU domain gene related to the mouse germ-line-specific transcription factor oct-3. Zebrafish pou2 is maternally expressed, and the transcripts are present from the one-cell stage to the gastrula stage. In situ hybridization analyses revealed that the transcripts were present in all blastomeres until the midblastula stage and that the expression was restricted to the epiblast during gastrulation. We found that alternatively spliced transcripts, t-pou2 RNAs, were also expressed in the embryos. In contrast to the Pou2 product, the t-Pou2 product lacks DNA-binding activity because of its incomplete POU domain structure. To examine the roles of the Pou2 and t-Pou2 products, we increased their expression in the embryo by microinjection of synthetic pou2 and t-pou2 RNAs into the fertilized eggs at the one-cell stage. Most embryos that developed from the eggs injected with pou2 RNA did not show any obvious developmental defects. In contrast, overexpression of the t-Pou2 product greatly affected the embryonic development: There was strong developmental retardation or arrest due to the incomplete gastrulation. In the affected embryos, expression of zebrafish T gene was reduced and the hypoblast formation was disturbed. Temporal and spatial expression patterns and the effects of overexpression of these products on development are consistent with the idea that the Pou2 and t-Pou2 proteins are involved in early development of zebrafish embryos. They may be involved in the proliferation of blastomeres in undetermined state at the blastula stage and/or the early cell commitment events at the gastrula stage. Also, our results indicate that different products generated as a result of alternative splicing from the same gene possess distinct functional capacities.

Alternative Splicing↗
PubMed1994

[Influence of physical responses due to controlled frequency breathing during exercise].

The purpose of this study was to examine the influence of respiratory responses due to controlled frequency breathing (CFB) during steady state cycle ergometric exercise (50% of Peak VO2, 60rpm) and to compare their responses between long distance (L), badminton (B), Swimming (S) and untrained (C; Control) group. Twenty-two (n = 6; L, B, C.n = 4; S) female university students were forced to take CFB for 1 min every 3 min during 20 min exercise. The breathing frequencies (BR) were 10, 12, 15, 20 and 30 frequencies in a minute. They were represented by CFB10, CFB12, CFB15, CFB20 and CFB30 respectively. In addition, CFB5, and 40 were given in a separate series. Ventiratory volume (VE) decreased significantly, (P < 0.05) when BR decreased less than about 50% of normal breathing (NB), CFB15 in (B) and (C). It showed to be less than CFB12 in (S), and CFB10 in (L). According to the decrease of VE, tidal volume and O2 pulse increased during CFB10 and 15 in all groups to maintain a constant O2 consumption for a given workload. End tidal partial pressure of O2 (PETO2) significantly decreased during less than CFB15 in (B) and (C), during CFB10 in (L). PETCO2 increased during less than CFB15 in (B), less than CFB12 in (L) and (C). However in (S) during every CFB, neither PETO2 nor PETCO2 changed significantly. Talking about the main differences shown between the four groups, (S) and (L) significantly exceeded (C) in maintaining of VE during CFB. However, in consideration of a ratio of the frequency of CFB to that of NB, (L) could maintain VE against more strictly controlled of breathing than other groups. (B) showed similar tendencies as (C) about some responses. It is considered that these differences in respiratory responses to CFB may result from difference of the duration and the level of breathing control that were forced during their daily training rather than whether their breathing frequency during each exercise is high or low.

Adult↗
PubMed1994

[Experimental techniques for developing new drugs acting on dementia (5)--Screening method in drug evaluation on neurite regeneration in primary cultured neurons].

Neurite regeneration is one of the important processes in the reconstruction of neuronal networks. We observed neurite elongation and branching of an individual neuron cultured at a comparatively low cell density. We also observed neurite re-elongation and branching of neurites amputated by a laser beam. Screening method in drug evaluation on neurite regeneration in primary cultured neurons and effects of basic fibroblast growth factor (bFGF) and astrocyte-derived conditioned medium (ACM) are explained in this report.

Animals↗
PubMed1994

[Hypersensitivity pneumonitis--histopathology of summer-type hypersensitivity pneumonitis].

Summer-type hypersensitivity pneumonitis(SHP) first reported by T. OCHI, et al. (1978), as a new type hypersensitivity pneumonitis(HP) with features of initiation during summer and anti-Cryptococcus antibody positive sera, has been recognized as "a unique disease in Japan", a most common type of HP in Japan, and now also known as anti-Trichosporon cutaneum antibody-positive SHP. This report was mainly concerned with the histopathology of SHP, thus far diagnosed in our hospital. Of the cases in our hospital, 62 consecutive biopsied cases (3 cases of open lung biopsy and 59 cases of transbronchial lung biopsy) without steroid institution before lung biopsy have been reviewed and revealed granulomatous interstitial pneumonitis in the bronchiolo-alveolar region, like various types of HP. Alveolitis (61 of 62 cases; 98.4%), sarcoid-like granuloma (50 of 62; 80.6%) and Masson's body (36 of 62; 58.1%) are main features, and could be named "triad" features. Concerning histopathological findings related with the period of lung biopsy after onset of clinical episodes as HP, alveolitis has been present regardless of period, and fibrinous exudate present in the early period and not in a case at 4 months. Sarcoid-like granuloma and Masson's body have appeared firstly at one-month cases. After this period sarcoid-like granuloma have been present in nearly all cases, but Masson's body has been not present in 10-month case with gradual decrease after 2 months, when all 2-month cases had it. In summary, for histopathological diagnosis of HP, the "triad" features and the time of lung biopsy done are keys, taking into consideration histopathological differential diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolitis, Extrinsic Allergic↗
PubMed1993

[Specific antibody-forming cells in bronchoalveolar lavage fluid of patients with summer-type hypersensitivity pneumonitis--detection by enzyme-linked immunospot (ELISPOT)].

Antigen-specific antibody-forming cells (AFCs) were assessed in bronchoalveolar lavage (BAL) fluid of patients with summer-type hypersensitivity pneumonitis by the method of enzyme-linked immunospot (ELISPOT). Both Cryptococcus- and Trichosporon-specific AFCs of isotypes of IgG, IgA and IgM were detected in BAL fluid cells. The frequency of isotypes of AFCs was in the order of IgA > IgM > IgG. Antibody activities against both Cryptococcus and Trichosporon antigens were detected in the culture supernatant of BAL cells. A good correlation was observed between the number of AFCs and the degree of antibody activity of culture supernatant of BAL cells, particularly of IgA isotype. For the IgM and IgA isotypes, anti-Cryptococcus antibody activity correlated well with anti-Trichosporon antibody activity (r = 0.98, p < 0.0001). In several cases examined, antigen-specific AFCs were detected in in vitro culture of peripheral blood mononuclear cells of patients after stimulation with PWM. In the present study, we demonstrated that Cryptococcus neoformans and Trichosporon cutaneum antigen-specific AFCs were present in the lungs of patients with summer-type hypersensitivity pneumonitis, and the antibodies secreted therefrom reacted with both these antigens. The presence of memory B cells was also suggested in the peripheral blood of patients.

Adult↗
PubMed1992

A raised level of soluble CD8 in bronchoalveolar lavage fluid in summer-type hypersensitivity pneumonitis in Japan.

We used ELISA to measure soluble CD8 (sCD8) in the bronchoalveolar lavage fluid (BALF) and serum of patients with summer-type hypersensitivity pneumonitis (HP). The sCD8 levels in BALF were significantly higher in the patients with summer-type HP, surpassing those found in sarcoidosis and the other pulmonary diseases studied; however, the sCD8 levels in the serum of patients with summer-type HP did not differ from the levels of the healthy controls. The numbers of CD8+ T cells were increased in the BALF of the patients with summer-type HP, and there was a correlation between the sCD8 levels and the concentrations of CD8+ T cells. Gel filtration and polyacrylamide gel electrophoresis of the fluid revealed that the anti-CD8 monoclonal antibody-reactive components in the BALF of patients with pneumonitis corresponded to a protein with a molecular weight of between 52 and 54 kDa. Soluble CD8-rich fraction purified from the BALF of patients with summer-type HP augmented in vitro lymphocytes' proliferative responses stimulated with Cryptococcus neoformans, one of the causative agents for summer-type HP. Our result suggests that soluble CD8 in the BALF may play an important role in the pathogenesis of summer-type HP.

Adult↗
PubMed1991

Human acidic fibroblast growth factor has trophic effects on cultured neurons from multiple regions of brain and retina.

Neurotrophic activities of human recombinant acidic fibroblast growth factor (haFGF) were evaluated on primary cultured neurons from various brain regions and compared with those of CS23, modified human basic fibroblast growth factor. Survival of cultured neurons from embryonic day 16 (E16) rat cortex and substantia nigra was significantly increased by the addition of more than 10 ng/ml haFGF and that from the hippocampus was increased by 100 and 1000 ng/ml. However, enhancement of viability by haFGF was observed only in 1000 ng/ml-treated neurons from the striatum, thalamus, colliculus and cerebellum; and it was not observed in septal neurons. Survival of cultured neurons from postnatal day 15 rat on glial feeder layer was significantly increased by the addition of 1000 ng/ml haFGF, except for neurons from the septum. CS23 (10 ng/ml) increased the survival of cultured neurons from all regions mentioned above, and its effects were stronger than those of 1000 ng/ml haFGF. Addition of more than 10 ng/ml haFGF significantly increased the survival of cultured neurons from neonatal day 2 rat retina. Addition of 1000 ng/ml haFGF increased the choline acetyltransferase activity of E16 septal neurons slightly but significantly, but didn't increase the dopamine uptake activity of embryonic day E15 ventral midbrain. These results show that haFGF is effective on limited regions and ages of brain and retina, while CS23 is effective on all regions tested.

Animals↗
PubMed1991

A case of thymic cyst with elevated sialylated Lewis X-i, carbohydrate antigen 19-9 and tissue polypeptide antigen in the cystic fluid with no elevation of serum tumor markers.

A 56-year-old man, tentatively diagnosed as having cardiomegaly, was found to have a large cyst in the left anterior mediastinum. At thoracotomy a multilocular cystic mass containing a colorless serous fluid was found and resected. Histologically, the cyst was lined with flattened epithelial cells, and thymic tissue was present in the cyst's wall; a diagnosis of thymic cyst was made. There were no malignant components or inflammatory changes. Sialylated Lewis X-i (SLX), carbohydrate antigen 19-9 (CA19-9) and tissue polypeptide antigen (TPA) in the cystic fluid were markedly elevated, while the serum concentrations of these tumor markers were within the normal ranges. Immunohistochemical studies showed the epithelial cells lining the cyst to contain CA19-9 and SLX. The findings suggest the tumor markers to have originated in the thymic epithelium lining the cyst.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1991

Assessment of daily physical activity levels of severely disabled persons using heart rate series.

Daily physical activity levels of severely disabled persons were assessed by means of a statistical analysis of their heart rate during a 24-h period. A non-Gaussian probability density function of the heart rate was calculated and separated into two levels of heart rate distributions, i.e. a relatively lower heart rate for basic daily activity and a relatively higher heart rate relating to vigorous activity. Disabled persons with low ambulatory ability showed daily activity levels similar to normal subjects in the length of time and the level of the heart rate. Their daily activity satisfied their needs for maintaining good health. However, more prolonged vigorous activity in daily living was necessary to improve cardiovascular fitness. For severely disabled persons without ambulatory ability, almost all of the heart rates during daily activity were categorized into the lower heart rate distribution. Their low level of physical activity may lead to a serious decrease in cardiovascular function with its attendant risk of cardiopulmonary disease.

Activities of Daily Living↗
PubMed1991

[Mortality patterns of children with epilepsies in a children's medical center].

Two hundred and thirty-seven children have died who were seen in the Division of Neurology, Kanagawa Children's Medical Center from 1975 to 1989. They corresponded to about 11% of the total death in the hospital. A total of 128 cases of 237 deaths (54.0%) were suffering from epilepsies, most of whom were also complicated with other CNS disorders. The causes of death were pneumonia, respiratory failure and suffocation in 60%, whereas status epilepticus or convulsions only in 14%. About 40% of victims died at home or in an emergency room without effective resuscitation. Mortality was considered high in infantile spasms (16 out of 146, 11%) and in severe myoclonic epilepsy in infancy (4 out of 8, 50%). It was note worthy that 3 cases of severe myoclonic epilepsy in infancy died of status epilepticus and 2 died at home. Sixteen cases whose chief problems were partial epilepsies and severe myoclonic epilepsy in infancy, died of status epilepticus in 10 cases, convulsions after tonsillectomy, etc. Causes of death of these 16 cases were related to convulsions except in two cases whose causes were pneumonia in one and unknown in the other. About a half of them (7 cases) died at home. Adequate managements appeared necessary to prevent accidental deaths of children with epilepsies.

Cause of Death↗
PubMed1991

[Four cases of Cockayne syndrome].

The evaluation of four patients with Cockayne syndrome (CS) by computed tomography (CT) and magnetic resonance imaging (MRI) is reported. All patients had characteristic clinical manifestations of CS. In a special respect, we found hyperopia in two patients and previous habitual abortions in two maternal histories. Extrapyramidal signs were seen in one patient. Three patients are type 1 CS (case 1, 3, 4) and one patient (case 2) is type 2 CS (congenital form). The cranial CT in two patients (case 1, 2) revealed prominent calcifications in basal ganglia, dentate nucleus and hemispheric white matter. While CT showed vagal calcifications in basal ganglia in other two patients (case 3, 4), T2-weighted MRI revealed obvious low intensity area in putamen and caudate nucleus, and high intensity area in the white matter. Sagittal section revealed atrophic changes of cerebellar vermis and brain stem. Thus it seems that MRI may be useful diagnostic adjunct in CS patients.

Brain↗
PubMed1990

A single cell observation of staurosporine effect on the Ca2+ signals in rat basophilic leukemia cells.

A digital imaging fluorescence microscope was used to study the effect of a protein kinase inhibitor staurosporine on the antigen-dependent calcium signals in an individual rat basophilic leukemia cell (RBL-2H3). Although dose dependency of staurosporine was different from one cell to another, staurosporine inhibited, at low concentration, the calcium influx from the external medium into RBL-2H3 cells. At high concentration, however, it inhibited both the removal of calcium ion from internal stores and the calcium influx from the external medium. These results indicated that staurosporine is necessary for the inhibition of the calcium influx from the external medium and that a protein kinase (possibly protein kinase C) is involved in the calcium influx from the external medium into the cytoplasm.

Alkaloids↗
PubMed1990

Non-stationary analysis of electromyographic activity prior to a ballistic voluntary contraction.

The electromyogram (EMG) in a ballistic voluntary action of muscle after a slight sustained contraction shows a short period of decrease or disappearance of the activity prior to the onset of phasic discharge. The EMG of elbow extensor (triceps brachii) prior to phasic discharge was analyzed as a non-stationary stochastic process. The distribution of the EMG amplitude began to change from 100 ms before the phasic discharge. The statistical test showed that the EMG activity became non-Gaussian from 30 to 50 ms before the phasic discharge. The standard deviation of the EMG showed a decreasing tendency from 80 to 100 ms prior to the phasic discharge. The statistical evidence for the EMG depression was also confirmed in fourth and sixth order coefficients of the orthogonal expansion of the probability density function. These results suggested that the EMG process profoundly changed its statistical characteristics just before the phasic discharge.

Action Potentials↗