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T Miyamoto

Publications and source records attributed to T Miyamoto.

At least 127 records · Page 7Linked to original sources
PubMed2001

Presurgical postictal and acute interictal psychoses are differentially associated with postoperative mood and psychotic disorders.

The authors studied 52 patients who had undergone surgery because of intractable temporal lobe epilepsy. Investigation of postoperative psychiatric illnesses focused on psychotic disorder (293.81 and 293.82) and mood disorder (293.83) due to a general medical condition diagnosed according to DSM-IV criteria. Presurgically, two episodic psychotic syndromes, acute interictal and postictal psychosis, were defined operationally. A correlation was confirmed between presurgical acute interictal psychosis and postsurgical psychotic disorder, as well as between presurgical postictal psychosis and postsurgical mood disorder. An excellent final outcome for postoperative mood disorder in contrast to a less favorable one for psychotic disorder was also suggested.

Acute Disease↗
PubMed2001

Constituents of holothuroidea. 10. Isolation and structure of a biologically active ganglioside molecular species from the sea cucumber Holothuria leucospilota.

Three ganglioside molecular species, HLG-1 (1), HLG-2 (2), and HLG-3 (3) have been obtained from the lipid fraction of the chloroform/methanol extract of the sea cucumber Holothuria leucospilota. The structures of these gangliosides have been determined, on the basis of chemical and spectroscopic evidence, as 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (1), 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->4)-(N-acetyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (2) and 1-O-[alpha-L-fucopyranosyl-(1-->11)-(N-glycolyl-alpha-D-neuraminosyl)-neuraminosyl)-(2-->4)-(N-aetyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (3). The ceramide moieties were composed of heterogeneous phytosphingosine, sphingosine and 2-hydroxy fatty acid units. Compounds 2 and 3 represent new ganglioside molecular species. These three ganglioside molecular species showed neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cell, in the presence of NGF (nerve growth factor).

Animals↗
PubMed2001

Conservative treatment of hemolytic complication following coil embolization in two adult cases of patent ductus arteriosus.

Two adult cases of relatively large patent ductus arteriosus (PDA) were treated by coil embolization, but were complicated by hemolysis that was successfully managed by medical treatment. Case 1 was a 67-year-old woman and Case 2 was a 71-year-old woman with a PDA of minimal diameter of 5.3 mm and 5.5 mm, respectively. The approach was via the pulmonary artery and 2 coils were delivered simultaneously into the ductus, known as the 'kissing coil technique'. Although immediately after the procedure only a small residual shunt was revealed by aortogram, hemolysis occurred for several hours after the procedure in both cases. A hemolytic complication usually needs additional coil embolization or surgical treatment, but in these 2 cases it was successfully treated by haptoglobin infusion to prevent nephropathy and by antiplasmin infusion to promote thrombus formation. Hemolytic complications of coil embolization of PDA can managed by medication when the residual shunt is minimal and the degree of hemolysis is mild.

Aged↗
PubMed2001

Improvement of freezing tolerance in transgenic tobacco leaves by expressing the hiC6 gene.

A cryoprotective protein, HIC6, was expressed transgenically in tobacco, a cold-sensitive plant, and the localization of the protein within the cell as well as freezing tolerance of the transgenic tobacco was investigated. For constitutive expression of HIC6 in tobacco, its corresponding gene was subcloned into pBI121. Through the transformation with pBI121/hiC6, fifteen transgenic tobacco lines were acquired, out of which twelve lines expressed the HIC6 protein. None of the transgenic tobacco lines, however, showed significant differences in freezing tolerance from the control plants (wild-type and transformed with pBI121) at -1, -3, and -4 degrees C, with the exception that their freezing temperature was -2 degrees C. In order to increase the accumulation level of HIC6, pBE2113 with a stronger promoter was used. Eight lines expressed the protein out of thirteen lines transformed with pBE2113/hiC6. The accumulation levels of the protein were clearly higher in the tobacco plants transformed with pBE2113/hiC6 than in those with pBI121/hiC6. The HIC6 protein seemed to be localized in mitochondria of the transgenic tobacco plants. Freezing-tolerance tests at -1 - -4 degrees C showed that the degree of electrolyte leakage was significantly lower in the plants with pBE2113/hiC6 than in the control plants. A leaf browning observation also showed that high accumulation of HIC6 significantly suppressed injury caused by freezing to the transgenic tobacco at -3 degrees C.

Algal Proteins↗
PubMed2001

Soybean resistant proteins interrupt an enterohepatic circulation of bile acids and suppress liver tumorigenesis induced by azoxymethane and dietary deoxycholate in rats.

We found that azoxymethane and dietary deoxycholate induced liver tumors in rats. The incidence and the development of the tumor were closely related to the enterohepatic circulation of bile acids. The feeding of a high-molecular-weight fraction of soy protein digest (HMF) suppressed the tumorigenesis, probably due to the inhibitory effect of soybean resistant protein on reabsorption of bile acids in the intestine.

Animals↗
PubMed2001

Attachment of Malassezia pachydermatis to the ear dermal cells in canine otitis externa.

To investigate the predominance of Malassezia pachydermatis (M. pachydermatis) as a causative agent of canine otitis externa, ear cerumen samples were observed for adhesion of M. pachydermatis to the cornified epithelial cells by light and electron microscopes. The yeasts appeared not to adhere to the cornified epithelial cells directly, but they seemed to exist in the proximity of the epithelial cells with an electron opaque halo-like space around them. Polysaccharide and lipid staining techniques were conducted to identify the substances existing in that space. Lipid substances, not saccharides, were observed around the yeasts and the cornified epithelial cells. These results suggested that in the canine ear canal malassezia yeast attachment to the cornified epithelial cells is mediated by lipids.

Animals↗
PubMed2001

X-ray hypersensitivity in the LEA rat: genetic linkage analysis of responsible loci.

The LEA rat was established from a Long-Evans rat closed colony as the control strain of the LEC rat, which is reported to exhibit several mutant phenotypes such as hepatic disorder (hts), blockage of the T cell differentiation (thid) and X-ray hypersensitivity (xhs1 and xhs2). Here we report that the LEA rat is hypersensitive to X-rays to a similar degree as the LEC rat, although it is normal with respect to the hts and thid phenotypes. We further performed genetic linkage analysis of X-ray hypersensitivity in the LEA rat. The quantitative trait loci (QTL) linkage analysis revealed that xhs1 but not xhs2 is the locus responsible for X-ray hypersensitivity in the LEA rat.

Animals↗
PubMed2001

Genetic association between low expression phenotype of CD62L (L-selectin) in peripheral CD4+ T cells and the thid (T-helper immunodeficiency) phenotype in the LEC rat.

Genetic linkage analysis was performed between the low expression phenotype of peripheral CD4+ T cells and the thid (T-helper immunodeficiency) phenotype using (BN x LEC)F1 x LEC backcross progenies. In contrast to a previous result using a thid congenic strain that the low expression phenotype of CD62L was not correlated with the thid phenotype, our result in this study indicated that the low expression phenotype of CD62L was genetically linked with the thid phenotype. The discrepancy between the previous and present results may be due to the source of animals, congenic strain versus backcross progenies. It is suggested by this study that the thid locus controls the expression level of CD62L in peripheral CD4+ T cells.

Animals↗
PubMed2001

Saccharin activates cation conductance via inositol 1,4,5-trisphosphate production in a subset of isolated rod taste cells in the frog.

The transduction mechanism of the conductance activated by saccharin was analysed in isolated bullfrog taste cells under whole-cell voltage-clamp. Bath application of 30 mM saccharin induced an inward current of -34 +/- 12 pA (mean +/- SEM, n = 10) at a membrane potential of -50 mV in 10 (23%) of 44 rod cells. The concentration-response relationship for the saccharin-gated current was consistent with that of the gustatory neural response. The saccharin-induced current was accompanied with a conductance increase under internal low Cl- condition (E(Cl) = -56 mV), suggesting that saccharin activated a cation conductance. The reversal potential of the saccharin-induced current was -17 +/- 2 mV (n = 10). Intracellular dialysis of 0.5 mM guanosine 5'-O-(2-thiodiphosphate) (GDP-beta-S) completely blocked the saccharin-induced response, suggesting the involvement of a G protein in the transduction. The dialysis of heparin (1 mg/mL) also inhibited the response almost completely, but the dialysis of 1 mM 8-Br-cAMP did not affect the response significantly. Intracellular 50 microM inositol 1,4,5-trisphosphate (1,4,5 InsP(3)) also induced the inward current in five (38%) of 13 rod cells, but intracellular Pasteurella multocida toxin (5 microg/mL, G alpha q-coupled PLC activator) did not elicit any response in the cells. The results suggest that saccharin mainly activates a cation conductance in frog taste cells through the mediation of IP3 production.

Animals↗
PubMed2001

Integrin expression and usage by prostate cancer cell lines on laminin substrata.

During prostate cancer progression, invasive glandular epithelial cells move out of the ductal-acinar architecture and through the surrounding basement membrane. Extracellular matrix proteins and associated soluble factors in the basal lamina and underlying stroma are known to be important regulators of prostate cell behaviors in both normal and malignant tissues. In this study, we assessed cell interactions with extracellular matrix and stromal factors during disease progression by characterizing integrin usage and expression in a series of parental and lineage-derived LNCaP human prostate cancer cell lines. Although few shifts in integrin expression were found to accompany disease progression, integrin heterodimer usage did change significantly. The more metastatic sublines were distinct in their use of alphavbeta3 and, when compared with parental LNCaP cells, showed a shift in alpha6 heterodimerization, a subunit critical not only for interaction with prostate basal lamina but also for interaction with the bone matrix, a favored site of prostate cancer metastases.

Adenocarcinoma↗
PubMed2001

[Clinical result of thermochemoradiotherapy for advanced head and neck cancer].

Since 1986, we have applied thermochemo (CDDP) therapy combined with radiotherapy to 18 patients with 25 advanced and/or recurrent head and neck cancers (thermochemoradiotherapy: TCR). In this report, the effects of TCR were compared with those of radiochemotherapy (RC) without hyperthermia for 22 patients with 27 cancers before 1985 in our department. Thermochemotherapy was performed twice a week, for a total of 8.8 times on average. Three kinds of heating system were used: a radiofrequency system, a microwave system, and a RF interstitial system. In the TCR group, 11 lesions (44.0%) showed a complete response (CR), 12 lesions (48.0%) a partial response (PR), and 2 lesions (8.0%) no change (NC). Therefore, the total response rate was 92.0%. After treatment with only RC, 5 lesions (18.5%) showed a CR, 12 lesions (44.5%) a PR, and 10 lesions (37.0%) NC, giving a total response rate of 63.0%. There was a significant difference in the CR and total response rate between these two groups. Furthermore, the 5-year cumulative local control and survival rates in the TCR group were 68.2% and 44.4%, and in the RC group were 22.2% and 18.2%, respectively. There was a significant difference in the local control rate between these two groups. In conclusion, thermochemoradiotherapy is an effective strategy for patients with advanced head and neck cancers.

Adult↗
PubMed2001

[Clinical significance of measuring inferior vena cava dimension in patients with acute exacerbation of chronic heart failure].

OBJECTIVES: This study determined the clinical significance of measuring the inferior vena cava dimension in patients with heart failure. METHODS: The subjects were 373 patients admitted due to acute exacerbation of chronic heart failure. The relationships were examined between inferior vena cava dimension in the end-expiratory phase on admission and in the stable state and etiology of heart failure, age, New York Heart Association (NYHA) functional classification in the stable state (before exacerbation), body weight, grade of tricuspid regurgitation, left ventricular end-diastolic dimension and left ventricular ejection fraction measured by two-dimensional echocardiography in the stable state and on admission, severity of lung congestion (Killip's classification) on admission, and clinical course during treatment. RESULTS: The inferior vena cava dimension was not correlated with etiology, age, NYHA functional classification, body weight, left ventricular end-diastolic dimension or left ventricular ejection fraction, but was correlated with the grade of tricuspid regurgitation (r = 0.78, p < 0.0001 in the stable state, r = 0.60, p < 0.0001 and on admission). The severity of lung congestion did not correlate with inferior vena cava dimension on admission or the increase in inferior vena cava dimension. The increase in body weight on admission was correlated with the increase in inferior vena cava dimension (r = 0.83, p < 0.0001), but did not correlate with inferior vena cava dimension on admission. Tricuspid regurgitation grade and inferior vena cava dimension were restored to the stable state when body weight reached stable state after treatment in patients (n = 202) with inferior vena cava dimension increased by over 5 mm on admission. CONCLUSIONS: Inferior vena cava dimension in patients with heart failure is correlated with the tricuspid regurgitation grade in the stable state and at acute exacerbation. The increase in inferior vena cava dimension between stable and exacerbated states, but not the actual value, is clinically useful to evaluate patients with acute exacerbation of chronic heart failure.

Chronic Disease↗
PubMed2001

Natural history of hypertrophic cardiomyopathy: Japanese experience.

BACKGROUND AND OBJECTIVES: Most patients with hypertrophic cardiomyopathy (HCM) remain clinically stable for long periods of time, whereas some patients progress to severe systolic dysfunction. Therefore, the natural history of HCM is largely unknown. METHODS: The present study followed up 59 patients with HCM (32 males, 27 females, mean age 38.6 +/- 13.6 years) for 10 years or more (mean 16.0 +/- 4.7 years) after the initial diagnosis. RESULTS: Eight of 17 patients who showed abnormal Q-waves at the initial examination had lost Q-waves, suggesting remodeling from asymmetric to generalized hypertrophy. The thickness of the interventricular septum showed remarkable changes, increasing by > or = 5 mm in 7 patients and decreasing by > or = 5 mm in 21. These observations indicate that ventricular remodeling occurs in patients with HCM. Follow-up electrocardiography demonstrated new Q-waves in 10 patients and bundle branch blocks or intraventricular conduction disturbances in 13. Left ventricular end-diastolic diameter increased from 41.6 to 48.1 mm, associated with a decrease in fractional shortening from 40.6% to 34.0%. Left ventricular systolic dysfunction, defined as left ventricular end-diastolic diameter > 55 mm or fractional shortening < 25%, developed in 13 patients. These observations indicate that myocardial disease including the conduction system is progressive in patients with HCM and finally deteriorates to systolic dysfunction. Left ventricular outflow obstruction also presented evolutional changes. At the initial study, 23 patients showed systolic anterior motion of the mitral valves. Systolic anterior motion disappeared in 13 patients, reduced in 2, increased in 2, and remained stable in only 6. One patient without systolic anterior motion at the initial study developed new systolic anterior motion. Impaired left ventricular filling increased left atrial diameter from 35.5 to 46.9 mm and atrial fibrillation frequently developed (24 patients). CONCLUSIONS: These findings suggest that HCM is a slowly progressive disease which develops evolutional remodeling of left ventricular hypertrophy and outflow obstruction, eventually progressing to systolic dysfunction with cavity dilation and wall thinning.

Adult↗
PubMed2001

[Molecular genetic studies of mitochondrial ornithine transporter deficiency (HHH syndrome)].

Mitochondrial ornithine transporter deficiency has been called HHH syndrome, because this disorder is characterized by three biochemical abnormalities; hyperornithinemia, hyperammonemia, and homocitrullinuria, and presents with various neurological symptoms; mental retardation, spastic paraparesis with pyramidal signs, cerebellar ataxia and episodic disturbance of consciousness or coma due to hyperammonemia. We identified four mutations in the mitochondrial ornithine transporter gene (ORNT1) of Japanese patients with HHH syndrome. These include a nonsense mutation (R179X), associated with exon skipping, missense mutations (G27E, P126R), and an insertion of AAC between codons 228 and 229, leading to an insertion of amino acid Asn. Especially, R179X was detected 4 of 7 Japanese patients (8 of 14 alleles), implying that this is a common mutation in Japanese population.

Amino Acid Transport Systems, Basic↗
PubMed2001

Developmental morphology of blood and lymphatic capillary networks in mammalian hearts, with special reference to three-dimensional architecture.

The development of blood and lymphatic capillaries in the cardiac ventricles was studied using the rat and monkey hearts from later gestation to adulthood. For scanning electron microscopy, the tissue was treated with ultrasonication followed by HCl in order to remove epicardial mesothelial cell, subepicardial connective tissue and basement membrane. At the end of fetal life and neonate, the blood capillaries ran in parallel between the bundles consisting of several cardiac myocytes with small size. Endothelial extensions were found frequently. Numerous pericytes with short processes were observed on the capillary wall. Blood capillaries in the pubertal myocardium ran between cardiac myocytes to form a dense network. Processes of pericytes became elongated along the capillaries. In the adult, the capillaries showed occasionally Y-shaped branching and H-shaped anastomoses. The lymphatic capillaries were identified by large, variable sizes and absence of pericytes. In early postnatal rats, they appeared in the subepicardial region. In young and adult animals, the lymphatic capillary networks with relatively dense reticular meshes surrounded the bundles of several myocytes. It was noted that numerous nerve fibers were in close to the lymphatic capillary wall.

Aging↗