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Biomedical subjects

T Tsuda

Publications and source records attributed to T Tsuda.

At least 253 records · Page 14Linked to original sources
PubMed1995

Cloning of a gene bearing missense mutations in early-onset familial Alzheimer's disease.

Some cases of Alzheimer's disease are inherited as an autosomal dominant trait. Genetic linkage studies have mapped a locus (AD3) associated with susceptibility to a very aggressive form of Alzheimer's disease to chromosome 14q24.3. We have defined a minimal cosegregating region containing the AD3 gene, and isolated at least 19 different transcripts encoded within this region. One of these transcripts (S182) corresponds to a novel gene whose product is predicted to contain multiple transmembrane domains and resembles an integral membrane protein. Five different missense mutations have been found that cosegregate with early-onset familial Alzheimer's disease. Because these changes occurred in conserved domains of this gene, and are not present in normal controls, they are likely to be causative of AD3.

Alzheimer Disease↗
PubMed1995

Cloning and characterization of pentylenetetrazol-related cDNA, PTZ-17.

cDNAs related to pentylenetetrazol-induced bursting activity in neurons were screened by a differential hybridization method using normal and pentylenetetrazol-treated primary cultured neurons from the cerebral cortex of mice. Twenty clones of candidate cDNA with expression increased or decreased by treatment with pentylenetetrazol were obtained. One of them, PTZ-17, was sequenced. Injection of PTZ-17 derived RNA into Xenopus oocytes showed a large calcium inward current with extracellular application of pentylenetetrazol.

Animals↗
PubMed1995

Ingested arsenic and internal cancer: a historical cohort study followed for 33 years.

A historical cohort study was conducted to investigate the long-term effect of exposure to ingested arsenic. The 454 residents who had been identified in a list made in 1959 were followed until 1992. They lived in an arsenic-polluted area, called Namiki-cho, Nakajo-machi, in Niigata Prefecture, Japan, and used well water containing inorganic arsenic. The exposure period was estimated to be about 5 years (1955-1959). Death certificates for the people who died between 1959 and 1992 were examined, and a total of 113 of the 454 residents were estimated to have drunk well water containing a high dose of arsenic (> or = 1 ppm). The standardized mortality rate ratios of these 113 residents were 15.69 for lung cancer (observed/expected = 8/0.51; 95% confidence interval (CI) 7.38-31.02) and 31.18 for urinary tract cancer (observed/expected = 3/0.10; 95% CI 8.62-91.75). Cox's proportional hazard analyses demonstrated that the hazard ratios of the highest exposure level group (> or = 1 ppm) versus the background exposure level group (0.001 ppm) were 1.74 (95% CI 1.10-2.74) for all deaths and 4.82 (95% CI 2.09-11.14) for all cancers. The analysis according to the skin signs of chronic arsenicism in 1959 showed that they were useful risk indicators for subsequent cancer development. In the development of lung cancer, there was evidence of synergism between arsenic intake and smoking habit.

Adolescent↗
PubMed1995

Manipulation of a single cell with microcapillary tubing based on its electrophoretic mobility.

Manipulation of a single cell of spherical shape, approximately 5-10 microns in diameter, was performed with capillary tubing and an electrostatic field. A single cell migrates with its electrophoretic mobility into capillary tubing against the flow of electroosmosis coming out of the capillary. After trapping the cell in the capillary, it is pulled out into the other microreservoir with the application of a reverse electric voltage. When we apply a negative voltage to the microreservoir itself, the cell in it can keep floating for a relatively long period due to electrostatic repulsion. The electrophoretic mobility of a single cell is also estimated.

Animals↗
PubMed1995

Immunohistochemical study of calpain and its endogenous inhibitor in the skeletal muscle of muscular dystrophy.

A calcium-dependent proteinase (calpain) has been suggested to play an important role in muscle degradation in Duchenne muscular dystrophy (DMD). In immunohistochemical studies, calpain and its endogenous inhibitor (calpastatin) were located exclusively in the cytoplasm in normal human muscles. The intensity of the staining was stronger in type 1 than in type 2 fibers. Quantitative immunohistochemical study showed an increase of calpain in biopsied muscles from the patients with DMD and Becker muscular dystrophy. Abnormal increases in calpain and calpastatin were demonstrated mainly in atrophic fibers, whereas necrotic fibers showed moderate or weak immunoreactions for the enzymes. Opaque fibers and hypertrophic fibers were negative. Not all dystrophin-deficient muscle fibers necessarily showed a strong reaction for calpain. We suggest that calpain may play an important role in muscle fiber degradation, especially in the early stage of muscle degradation in muscular dystrophy.

Adolescent↗
PubMed1995

Two visual pigment opsins, one expressed in the dorsal region and another in the dorsal and ventral regions, of the compound eye of a dragonfly, Sympetrum frequens.

This paper describes the primary structure of two visual pigment opsins (DfRh1 and DfRh2) in the regionalized compound eye of a dragonfly, Sympetrum frequens. The amino acid sequences were deduced from the nucleotide sequences of cDNAs isolated from a cDNA library of the dragonfly retina. The two opsins both consist of 379 amino acids with 81.3% identity. Analysis of hydropathy indicated that the sequences have seven transmembrane domains like those of previously described opsins. Expression analysis using RT-PCR revealed that DfRh1 was present only in the dorsal region whereas DfRh2 was detected in both the dorsal and the ventral regions of the eye.

Amino Acid Sequence↗
PubMed1995

An immunohistochemical investigation of porcine epidemic diarrhoea.

A sudden outbreak of epidemic diarrhoea of piglets occurred in Japan, the principal features being watery diarrhoea, dehydration and high mortality in newborn animals. The microscopical lesions were villous atrophy in the small intestine, the villous enterocytes being vacuolated and cuboidal in shape. The villus-crypt ratio was severely reduced, varying from 1:1 to 3:1. Transmission electron microscopy showed numerous coronaviruses within the cytoplasm of enterocytes and among microvilli. Specific antigens of porcine epidemic diarrhoea (PED) virus were detected in the cytoplasm of enterocytes by the streptavidin-biotin (SAB) technique. Infected cells, which were most abundant in the villous epithelia of the jejunum and ileum, were present in small numbers in the large intestine, the crypt epithelia, the lamina propria and Peyer's patches. The study suggests that the SAB technique is useful for the diagnosis of PED.

Animals↗
PubMed1995

Correlations of antimyosin accumulation and histological manifestation of myocyte necrosis at different stages of idiopathic cardiomyopathy.

Although antimyosin uptake has been demonstrated in idiopathic cardiomyopathy, discrepancies between antimyosin positivity and histological examinations using biopsy speciments have been found. In order to investigate the correlations between antimyosin localization and histopathological alterations, the magnitude and distribution of antimyosin uptake were quantitatively assessed in aged-matched control (F1b) and hereditary idiopathic cardiomyopathy (Bio 14.6) hamsters at three different ages. In these studies, gamma counting and macroautoradiography were compared with histological alterations. Myocardial activities and percent areas of antimyosin uptake were significantly (P<0.05) greater in 10-, 20-, and 30-week old Bio groups than in their respective control groups. Autoradiograms showed that antimyosin antibody was relatively localized, massive, and scattered in 10-week-old, 20-week-old and 30-week-old Bio hamsters, respectively. Histopathology demonstrated antimyosin positivity not only in necrotic myocytes and accompanying calcium deposits but also in tissues showing inflammatory reactions but no histologically identifiable myocyte necrosis. In conclusion, antimyosin uptake seen in tissues with age-related disease processes did not necessarily correspond to histologically verified myocyte necrosis in the cardiomyopathy hearts, suggesting that antimyosin positivity reflects myocytes which show impaired sarcolemmal integrity but have not yet undergone myolysis.

Animals↗
PubMed1995

Case report: intraglomerular metastasis with neoplastic cell interposition.

A case is described of an 88-year-old man with lung cancer, nephrotic syndrome, and renal dysfunction who died suddenly of an acute myocardial infarction and whose autopsy revealed many adenocarcinoma cells stacked within glomerular capillary lumina of his kidney, entering into basement membrane zones (ie, neoplastic cell interposition). In addition, glomeruli showed a lobular transformation, doubling of glomerular basement membrane, and electron dense deposits along the glomerular basement membrane. These changes were similar to those of membraneoproliferative glomerulonephritis. The association of intraglomerular metastasis and membranoproliferative glomerulonephritis-like lesions led the authors to speculate that the latter glomerular change might have provided an attractive opportunity for circulating tumor cells to be trapped and grow within the glomerular lumina. This mode of metastasis has not been well-recognized. The authors describe the experience, review the literature, and discuss its possible pathogenesis.

Adenocarcinoma↗
PubMed1995

Training in evaluation of expressed emotion using the Japanese version of the Camberwell Family Interview.

To evaluate the effect of training in rating expressed emotion (EE) using the Japanese version of the Camberwell Family Interview (CFI), interrater reliability between a certified rater and a trainee was examined. The material was 65 CFI interviews with the families of 46 schizophrenic patients. The two raters independently rated EE status, critical comments (CC), hostility (H), emotional overinvolvement (EOI), warmth (W) and positive remarks (PR). The interrater reliability was satisfactory with regard to EE status, CC, H, EOI and PR. In the category of W, however, the results were unsatisfactory, as there was no positive development of agreement over time. In fathers, the interrater reliability of W was lower than in other relationships. Use of interview transcripts could contribute to a more satisfactory interrater agreement in EOI, and this is recommended as a useful training tool in EE evaluation.

Adolescent↗
PubMed1995

Influences of season and of temperature, photoperiod, and subcutaneous melatonin infusion on the glomerular filtration rate of ewes.

Influences of season and of temperature, photoperiod, and subcutaneous melatonin infusion on glomerular filtration rate (GFR) were measured in ewes. There was a seasonal difference of GFR between summer (June-August) and winter (December-February) in Tokyo (35 degrees, 35' N); GFR was significantly (P < 0.05) higher in summer (4.2 +/- 0.3 ml/min/kg) than in winter (3.0 +/- 0.2 ml/min/kg). GFR was measured after exposure to three types of photoperiod, 24L:0D, 12L:12D, and 0L:24D, for 7 to 8 days. The value for GFR obtained at 20 degrees C was significantly lower (P < 0.05) with 0L:24D than with the other two photoperiodic conditions. GFR obtained during subcutaneous melatonin infusion (20 micrograms/hr for 16 hr/day for 7 days) with 24L:0D conditions was significantly (P < 0.05) lower (2.5 +/- 0.1 ml/min/kg) than without infusion (3.8 +/- 0.3 ml/min/kg) and was about the same as that obtained in animals under 0L:24D conditions. At 30 degrees C, GFR exhibited no difference between the 3 photoperiodic conditions and was always lower than that found at 20 degrees C. Possible influences of melatonin on GFR are discussed.

Animals↗
PubMed1995

Solitary pulmonary nodule: preliminary study of evaluation with incremental dynamic CT.

PURPOSE: To use incremental dynamic computed tomography (CT) to evaluate solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: Thirty-two adult patients with SPNs less than 3 cm in diameter had 18 primary lung cancers, 10 tuberculomas, and four hamartomas. The CT numbers of the inner area of the nodule were calculated before and 30 seconds, 2 minutes, and 5 minutes after administration of contrast material. RESULTS: All lung cancers and one of four hamartomas showed significantly greater enhancement (P < .0001) than benign SPNs, which did not show enhancement (except for one hamartoma). All lung cancers and one of four hamartomas showed complete enhancement, one hamartoma showed peripheral enhancement, two hamartomas and eight of 10 tuberculomas showed capsular enhancement, and two tuberculomas showed no enhancement. CONCLUSION: Maximum attenuation of 20-60 HU appears to be a good predictor of malignancy.

Adult↗
PubMed1995

Small peripheral lung carcinoma evaluated with incremental dynamic CT: radiologic-pathologic correlation.

PURPOSE: To correlate incremental dynamic computed tomographic (CT) and pathologic findings in peripheral lung cancer. MATERIALS AND METHODS: Lung lesions smaller than 3 cm in diameter were evaluated in 18 patients. CT values of the inner area of the nodule at plain CT and at 30 seconds, 2 minutes, and 5 minutes after administration of nonionic contrast material were calculated with incremental dynamic CT. Maximum attenuation was compared with pathologic type of lung carcinoma and with number of vessels and distribution of elastic fibers in the pathologic specimen. RESULTS: Enhancement of all lesions was statistically significant (P < .0001). Maximum attenuation of lung carcinomas correlated positively with number of small vessels (diameter, 0.02-0.10 mm) (r = .77). Distribution of elastic fibers in the tumoral interstitium correlated with maximum attenuation (P = .04 between grades 1 and 3) and with number of small vessels (P = .01 between grades 1-3; P = .008 between grades 1 and 3). CONCLUSION: Enhancement characteristics of lung carcinomas reflect the number of small tumoral vessels and the distribution of elastic fibers in the tumoral interstitium.

Adenocarcinoma↗
PubMed1995

A case of acute eosinophilic pneumonia caused by inhalation of Trichosporon terrestre.

We present the diagnostically challenging case of an 18-yr-old Japanese woman who presented with fever, nonproductive cough, and acute respiratory distress. Her chest radiograph showed diffuse interstitial infiltrates and bilateral pleural effusions. Eosinophilic pneumonia was diagnosed by bronchoalveolar lavage and transbronchial lung biopsy. She was treated with minocycline, and was discharged in 2 wk. However, within 3 h of returning home, she experienced a recurrence. She showed positive immediate, Arthus, and delayed-type skin reactions and positive lymphocyte stimulation test to an antigen derived from Trichosporon terrestre, which was isolated from dust in her home. In addition, a bronchoprovocation test with the same antigen caused a nonproductive cough with fever, hypoxemia, and peripheral eosinophilia. We concluded that T. terrestre was the causal agent of the acute eosinophilic pneumonia.

Acute Disease↗
PubMed1995

[Effect of physical activity on physical fitness among workers].

We conducted a cross-sectional study to clarify the effects of physical activity on physical fitness. Physical fitness tests were offered to workers of companies manufacturing automobile parts from December, 1992 to December, 1993. The subjects were 1,217 male and 600 female workers who participated in the physical fitness test. From this group, we analyzed 1,048 male and 522 female workers who answered a physical activity questionnaire. The questionnaire included age, sex, working posture, physical activity during working time and physical activity during leisure time. The physical fitness tests were composed of grip strength, standing trunk flexion, foot balance with closed eyes, jumping reaction time and step tests. We classified the subjects into low performance group and high performance group for each test. In addition, we classified the subjects into different groups by age (16-29 years old, 30-49 years old old and 50-69 years old), by working posture (standing and sitting), as well as by activity levels during working time and leisure time physical activities (inactive and active). Thus, we examined potential risk factors for the physical fitness by a multiple logistic regression model. The results were as follows: 1. Standing work was a significant risk factor for grip strength, foot balance with closed eyes and jumping reaction time in male workers, and standing trunk flexion, foot balance with closed eyes, jumping reaction time and the step test in female workers. 2. Physical activity during working time was not related to physical fitness in male and female workers. 3. Inactivity during leisure time was a significant risk factor for standing trunk flexion, foot balance with closed eyes, jumping reaction time and the step test in male workers, and grip strength and foot balance with closed eyes in female workers. 4. Young age (16-29 years old) was a significant risk factor for grip strength, standing trunk flexion, foot balance with closed eyes, jumping reaction time and the step test in male and female workers. Middle age (30-49 years old) was a significant risk factor for foot balance with closed eyes and jumping reaction time in male workers, and standing trunk flexion, foot balance with closed eyes, jumping reaction time and the step test in female workers.

Adolescent↗
PubMed1995

Congenital anophthalmia with caudal vertebral anomalies in Japanese Brown cattle.

Anophthalmia and caudal vertebral anomalies such as taillessness or wry tail were morphologically examined in ten Japanese Brown calves obtained in Kumamoto Prefecture. The anomalous calves lacked eyeball bilaterally or unilaterally but had small-sized eyelids and narrow palpebral fissures. A small cystic, solid or spot-like remnant of eyeball (REB) was buried in the mixture of vestigial extraocular muscles, lacrimal gland and adipose tissue of the orbit. The REB was composed of irregularly arranged elements of ocular wall such as sclera, choroid and retina. The retina was often dysplastic and connected to the hypoplastic optic nerve. These morphological changes might represent the defective processes after the formation of the optic vesicle or cup. Therefore, this eye defect may be defined as degenerative anophthalmia. The defects of the vertebral body such as wedge vertebra, hemivertebra, and sagittal cleft vertebra seen in the lumbar, sacral, and coccygial regions and the meandering of the axial line of abnormal vertebrae may suggest the failure of notochord formation in the early fetal period. From the embryological point of view, it seemed possible that the calves were exposed to teratogen at the critical time of optic organogenesis and notochordal formation. The cause of anomalies could not be determined in this study.

Animals↗
PubMed1995

Characterization of distribution of T lymphocyte subsets and activated T lymphocytes infiltrating into sarcoid lesions.

We studied the relationship between various T lymphocyte functions and granuloma formation in 5 lung tissue and 4 lymph node tissue samples from patients with sarcoidosis by immunohistological methods. In the lesion of sarcoidosis, T cells were positive for alpha beta TCR, but gamma delta TCR-positive T cells were rarely observed. The results of analysis of functional subsets showed that T cells in the internal area of granuloma were predominantly helper/inducer subset (CD4+CD45RA-). On the other hand, cytotoxic T cells (CD8+CD45RA-CD11b-) were present in abundance in the outer boundaries of granuloma. In addition, suppressor-inducer T cells (CD4+CD45RA+) were present in the surrounding areas. However, T cells of various subsets were present sporadically outside the granulomas. We also studied the distribution of T cells expressing activation-related antigens. The results showed that T lymphocytes in the internal area of granulomas more frequently had these antigens than did T lymphocytes in the external area. These findings suggested that T cells infiltrating into the sarcoidosis lesion demonstrated a layer-like distribution based on functional subsets. These findings also confirm that activated T cells were more abundantly distributed in the internal area of sarcoid granuloma than in the external area.

Antibodies, Monoclonal↗