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Y Tanabe

Publications and source records attributed to Y Tanabe.

At least 181 records · Page 10Linked to original sources
PubMed1994

The re-evaluation of sex steroids metabolism in patients with non-alcoholic liver cirrhosis.

We examined the serum levels of testosterone (T), androstenedione (delta 4-A), estrone (E1), estradiol (E2), and dehydroepiandrosterone sulfate (DHEA-S) in the non-alcoholic cirrhotic male patients when divided into compensated or decompensated state. Serum level of T was significantly elevated in compensated cirrhotic patients (9.63 +/- 1.00 ng/ml, mean +/- SE) compared to that in decompensated cirrhotic patients (5.63 +/- 0.69 ng/ml, p < 0.01) and in aged-matched normal controls (4.95 +/- 0.38 ng/ml, p < 0.01). Serum levels of E1, E2 and delta 4-A tended to be increased in decompensated cirrhotic patients, while there was not a significant difference decompensated cirrhosis compared to those of normal controls. Serum concentration of cholinesterase, indicative one of the representative residual liver function, showed a good positive correlation to T (r = 0.53, p < 0.01), and a negative correlations to E1 (r = -0.67, p < 0.01), E2 (r = -0.77, p < 0.01), delta 4-A (r = -0.57, r = p < 0.01). Also, we examined the relationship of the serum levels to gynecomastia or esophageal varices. The cirrhotics with gynecomastia showed significantly higher serum levels of E1, E2, and delta 4-A, and lower level of T than those without gynecomastia. And the cirrhotics with esophageal varices showed the greater level of T than those without esophageal varices. Our study suggests that low serum testosterone level of men with nonalcoholic cirrhotic is not a common finding, especially in compensated state.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Unique imagings of CT and MR in liver metastasis from gastric leiomyosarcoma.

We report unique features of computed tomography (CT) and magnetic resonance (MR) imaging in the metastatic lesion of the liver in a case of gastric leiomyosarcoma. A CT scan and MR image demonstrated presence of a huge multilocular cystic lesion in the liver, of which finding were unlike to those of usual smooth muscle tumors, but mimicked to those of cystadenomatous tumors. In addition, this case had an extremely long elapsing time over ten years from the radical operation for the primary site.

Aged↗
PubMed1994

Novel subtype of peroxisomal acyl-CoA oxidase deficiency and bifunctional enzyme deficiency with detectable enzyme protein: identification by means of complementation analysis.

We describe four infants with a novel subtype of an isolated deficiency of one of the peroxisomal beta-oxidation enzymes with detectable enzyme protein. The patients showed characteristic clinical and biochemical abnormalities, including hypotonia, psychomotor retardation, hepatomegaly, typical facial appearance, accumulation of very-long-chain fatty acids, and decreased lignoceric acid oxidation. However, beta-oxidation enzyme proteins were detected by immunoblot analyses, and large peroxisomes were identified by immunofluorescence staining. In order to identify the underlying defect in these patients, complementation analysis was introduced using fibroblasts from these patients and patients with an established deficiency of either acyl-CoA oxidase or bifunctional enzyme, as identified by immunoblotting. In the complementing combinations, fused cells showed increased lignoceric acid oxidation, resistance against 1-pyrene dodecanoic acid/UV selection, and normalization of the size and the distribution of peroxisomes. The results indicate that two patients with a more severe clinical course were suffering from bifunctional enzyme deficiency and that the other two infants, who were siblings and had a less severe clinical presentation, were the first patients with acyl-CoA oxidase deficiency with detectable enzyme protein.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1993

Role of the large extracellular domain of metabotropic glutamate receptors in agonist selectivity determination.

Metabotropic glutamate receptors consist of at least six different subtypes termed mGluR1-mGluR6. They belong to the family of G protein-coupled receptors and commonly possess an unusually large extracellular domain preceding the seven transmembrane segments. mGluR1 and mGluR2 show similar affinities for L-glutamate but distinct patterns in their responsiveness to quisqualate and trans-1-amino-1,3-cyclopentane-dicarboxylate (tACPD). To assign structural determinants for the different agonist selectivities, we constructed a series of chimeric receptors at the extracellular domains of mGluR1 and mGluR2 and determined their agonist selectivities by measuring their electrophysiological responses to L-glutamate, quisqualate, and tACPD in Xenopus oocytes. Replacement of the extracellular domain up to about one-half of the amino-terminal extracellular domain of mGluR1 with the corresponding portion of mGluR2 generated a pattern of the agonist selectivity characteristic of mGluR2. The acquirement of this property in agonist selectivity was further indicated by the selective responses of these chimeric receptors to an mGluR2-specific agonist, (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine. This investigation demonstrates that the extracellular domain of mGluR is critical in determining agonist selectivity and that the mode of determination of agonist selectivity of mGluR is different from that of other G protein-coupled receptors for small molecule transmitters.

Animals↗
PubMed1993

Lack of X inactivation: loss of one X inactivation center in a case with mos45,X,-21, +der(21)t(X;21) (p21.3;p11.2)/46,X,t(X;21) (p21.3;p11.2).

We present a girl with a mos45,X,-21, +der(21)t(X;21) (p21.3;p11.2)/46,X,t(X;21) (p21.3;p11.2) chromosome constitution. The ratio of these cells was 59/26 in phytohemagglutinin (PHA)-stimulated lymphocytes. The 45,X,der(21)t(Xp-;21p+) cells lacked an X inactivation center located at Xq13 on the derivative X chromosome; in these cells, the whole normal X chromosome and the distal part of Xp translocated onto the derivative chromosome 21 were early replicating. She had moderate mental retardation and other findings different from those that occur in the Ullrich-Turner syndrome. Her phenotype may be due to the functional excess of the distal part of Xp on the derivative 21 in 45,X,der(21)t(Xp-;21p+) cells; thus, this might be another type of the "lack of X-inactivation" syndrome.

Chromosome Banding↗
PubMed1993

Radiosensitization by a new potent nucleoside analog: 1-(1',3',4'-trihydroxy-2'-butoxy)methyl-2-nitroimidazole(RP-343).

PURPOSE: A new hypoxic cell sensitizer has been synthesized; this is a 2-nitroimidazole nucleoside analog having erythritol as a sugar moiety at the N-1 position of the imidazole ring (RP-343). Its possibility as a potent hypoxic cell sensitizer was compared with those of RP-170 and etanidazole. METHODS AND MATERIALS: Radiosensitization was tested in two murine tumors, EMT6 using in vitro and in vivo-in vitro assays and SCCVII using growth delay and TCD50 assays. Pharmacokinetic study was performed in Balb/c mice bearing EMT6 tumors and in Beagle dogs. LD50 of each sensitizer was obtained with ICR mice. RESULTS: As might be expected from the almost identical electron affinities of the three sensitizers, they were equally effective against hypoxic EMT6 cells in vitro. While having the lowest partition coefficient (0.035), RP-343 exhibited almost equally effective distribution to tumors and sensitizing radiation activity. An intravenous (i.v.) injection of 100 mg/kg of RP-343, RP-170 and etanidazole showed an almost equal sensitizer enhancement ratio (SER) of about 1.4 to solid EMT6 tumor under in vivo-in vitro assay and a virtually equal SER of 1.33-1.44 to solid SCCVII tumor under both tumor growth delay assay and TCD50 assay. A great advantage of RP-343 over RP-170 and etanidazole is its very much lower toxicity; their LD50 in mice were > 6.0, 4.3 and 4.8 g/kg, respectively, on i.v. injection. The lower toxicity of RP-343 was supported by its lower concentrations in the brain; the RP-343 AUC for brain was 0.43 times that of RP-170. Three indices were selected to compare the three nitroimidazoles. SER at 5% LD50 doses of RP-343, RP-170 and etanidazole was 1.66, 1.59 and 1.56. At the same toxicity levels, RP-343 was found to have better sensitization of solid tumors over both etanidazole and RP-170. The maximum tumor concentration/AUC for brain (Cmax,tumor/AUCbrain) ratios for RP-343 and RP-170 were 9.62 and 3.98. CONCLUSIONS: This extremely high ratio of RP-343 could explain its lower toxicity than RP-170 or etanidazole. The therapeutic risk index defined as D1.5/LD50 (D1.5 is the sensitizer dose to obtain the SER of 1.5 in vivo) for RP-343, RP-170 and etanidazole were 0.022, 0.033 and 0.036, respectively. Especially, the effectively lower therapeutic risk index for RP-343 presents the possibility of clinical advantage over etanidazole.

Animals↗
PubMed1993

Coexistence of substance P and calcitonin gene-related peptide in the nerve fibers of the carotid labyrinth of the bullfrog, Rana catesbeiana.

Double immunohistochemical staining with fluorescein isothiocyanate (FITC)- and rhodamine-conjugated antisera revealed the coexistence of substance P (SP) and calcitonin gene-related peptide (CGRP) in most nerve fibers in the intervascular stroma of the carotid labyrinth of the bullfrog, Rana catesbeiana. A few fibers contained SP without CGRP. The results suggest that the vascular regulatory function, which is one of the possible functions of the carotid labyrinth, may be controlled in part by the interaction of SP and CGRP.

Animals↗
PubMed1993

Preventive therapy against delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage: trials of thromboxane A2 synthetase inhibitor and hyperdynamic therapy.

The effects of thromboxane A2 synthetase inhibitor and hyperdynamic therapy on delayed cerebral ischaemia following aneurysmal subarachnoid haemorrhage were evaluated in a series of twenty eight patients, who underwent aneurysmal clipping with 72 hours after subarachnoid haemorrhage. Postoperatively, 13 patients were treated with thromboxane A2 synthetase inhibitor, Xanbon [sodium (E)-3-[p-(1H-imidazol-1-ylmethyl)phenyl]-2-propenoate]. Hyperdynamic therapy with dobutamine was given to the remaining 15 patients. Of the 13 patients treated with Xanbon, nine patients (69%) developed delayed cerebral ischaemia and cerebral infarcts occurred in eight patients (62%). On the other hand, of the 15 patients treated with hyperdynamic therapy, only three patients (20%) manifested delayed cerebral ischaemia and two patients (13%) developed cerebral infarcts. In the present study, the patients treated with hyperdynamic therapy met an expected incidence of ischaemic events after subarachnoid haemorrhage by today's standards, while those treated with thromboxane A2 synthetase inhibitor did not.

Adult↗
PubMed1993

Chemotherapy for minimally differentiated acute myeloid leukemia (AML-M0). A report on five cases and review of the literature.

With the objective of establishing the optimal therapy for minimally differentiated acute myeloid leukemia (AML-M0), we examined the therapeutic results of five AML-M0 cases and reviewed the literature. In a series of 63 patients with newly diagnosed acute leukemia who were admitted to the Main Hospital of Nippon Medical School, five patients fit the criteria for AML-M0: negative myeloperoxidase (MPO) and Sudan black B reaction by light microscopy, negative for B- and T-lineage markers, and positive for myeloid markers. They were treated by means of AdVP [adriamycin, vincristine, and prednisolone (PSL)] therapy and/or BHAC-DMP [behenoylcytosine arabinoside (BHAC), daunorubicin (DNR), 6-mercaptopurine (6-MP), and PSL] therapy. The AdVP therapy was unsuccessful in the two patients who received it, while a complete remission (CR) was achieved with the BHAC-DMP therapy in three of four patients. Although one patient treated with BHAC-DMP did not achieve CR, his blasts were apparently sensitive to the therapy. In assessable cases in the literature where leukemic blasts were MPO-negative, myeloid marker-positive and B- and T-lineage marker-negative, CR was achieved in 54.5% and 44.4% with anti-acute myeloid leukemia therapy and anti-acute lymphocytic leukemia therapy, respectively. Five cases in the literature were treated with a chemotherapeutic regimen containing BHAC [or cytosine arabinoside (Ara-C)], DNR, and 6-MP, and all achieved CR. The regimen containing BHAC (or Ara-C), DNR, and 6-MP may be useful as induction chemotherapy for AML-M0.

Adult↗
PubMed1993

Failure characteristics of osteoporotic vertebral bodies monitored by acoustic emission.

The third lumbar vertebrae of nine elderly subjects (average age, 81.4 +/- 6.7 years) graded osteoporotic and the second to fifth lumbar vertebrae of a 37-year-old man graded as normal were used to investigate microdamage accumulation during quasi-static compression loading with an acoustic emission detection system. Mechanical parameters (apparent elastic modulus, stress, and strain) and acoustic emission event count rates were measured simultaneously. The normalized mean value of any mechanical parameters of normal group was significantly high with respect to that of osteoporotic group. The normalized mean value of cumulative acoustic emission event counts to maximum stress of the normal vertebrae was substantially small with respect to that of the osteoporotic vertebrae (p < 0.0005, z-test). Postloading microradiographs displayed fracture lines adjacent to the end plates in six vertebrae of osteoporotic group. These results are consistent with the hypotheses that microdamages of osteoporotic vertebral bodies are generated and accumulate at lower strains than those of normal vertebrae at a specific site.

Adult↗
PubMed1993

Coronary artery spasm is a major cause of sudden cardiac arrest in survivors without underlying heart disease.

BACKGROUND: The role of coronary spasm in underlying disease-free patients who were resuscitated from sudden cardiac arrest remained uncertain. This study investigated the cause of cardiac arrest, and the etiologic and prognostic differences were compared between patients with underlying heart disease (group I) and those patients without underlying heart disease (group II). METHODS: Twenty-five survivors of sudden cardiac arrest were classified into two groups according to the presence or absence of underlying heart disease. To investigate the cause of cardiac arrest, we performed ergonovine testing and electrophysiologic study. Fifteen of the patients had underlying heart disease, while 10 did not. RESULTS: Electrophysiologic abnormalities were found in 13 of the 15 patients in group I. In group II, spontaneous attack of coronary spasm occurred in four patients during the observation period, and coronary spasm was induced in three of the remaining six period of 32 +/- 23 months, whereas no patients in group II had recurrence of sudden cardiac arrest at a median follow-up of 32 months (range, 10 to 72 months). CONCLUSIONS: Electrophysiologic study identified a potential cause in 13 of 15 patients with underlying heart disease. Coronary spasm was involved in the pathogenesis of sudden cardiac arrest in survivors without identifiable underlying heart disease.

Adolescent↗
PubMed1993

Megakaryocyte, erythroid and granulocyte-macrophage colony formation in myelodysplastic syndromes.

Bone marrow progenitor cell assays of three cell lineages, i.e., colony-forming unit megakaryocytes (CFU-Meg), burst-forming unit erythrocytes (BFU-E) and colony-forming unit granulocyte-macrophages (CFU-GM), were performed for 21 patients with myelodysplastic syndromes (MDS). Markedly reduced or absent colony formation was found in 67% of the patients for CFU-Meg and all patients except 2 with refractory anemia (RA) for BFU-E. Abnormal CFU-GM colony formation was found in only 5 of 12 patients with RA and RA with ring sideroblasts, in contrast to all of the RA patients with excess of blasts and excess of blasts in transformation. Defective colony formation of all three cell lineages was seen in 63% of the MDS patients. The colony number of CFU-Meg correlated significantly with the numbers of both BFU-E and CFU-GM. These findings indicate that hematopoiesis in MDS patients is disturbed due to a qualitative or quantitative defect at the multipotent stem cell level.

Adolescent↗
PubMed1993

Acute effect of percutaneous transvenous mitral commissurotomy on ventilatory and hemodynamic responses to exercise. Pathophysiological basis for early symptomatic improvement.

BACKGROUND: Improvement of exertional dyspnea occurs immediately after percutaneous transvenous mitral commissurotomy (PTMC), but the pathophysiological basis for this early symptomatic improvement has not been elucidated. METHODS AND RESULTS: Exercise hemodynamic measurement and exercise ventilatory measurement with arterial blood gas analysis were performed in 21 patients aged 50.4 +/- 9.5 years (mean +/- SD) with symptomatic mitral stenosis before and a few days after PTMC. Exercise ventilatory measurement were also performed in 14 normal control subjects aged 48.9 +/- 4.9 years. After PTMC, mitral valve area increased (from 1.0 +/- 0.3 to 1.7 +/- 0.3 cm2, P < .001), mean mitral gradient (from 12.2 +/- 5.2 to 5.2 +/- 2.2 mm Hg, P < .001), and mean left atrial pressure (from 18.7 +/- 6.1 to 12.1 +/- 4.0 mm Hg, P < .001) decreased. All patients experienced significant symptomatic improvement soon after PTMC. Comparison of hemodynamic parameters at the same ergometer work rate showed a significant decrease in pulmonary artery systolic pressure (from 77 +/- 18 to 67 +/- 14 mm Hg, P < .001) and diastolic pressure (from 36 +/- 10 to 28 +/- 7 mm Hg, P < .001) and a significant increase in cardiac output (from 6.4 +/- 1.4 to 8.1 +/- 1.9 L/min, P < .001). Despite the improvement in exercise hemodynamics and symptoms, exercise capacity determined by peak oxygen uptake (from 18.0 +/- 2.9 to 18.6 +/- 3.1 mL.kg-1 x min-1) and anaerobic threshold (from 11.7 +/- 2.4 to 12.0 +/- 2.4 mL.kg-1 x min-1) remained unchanged. Excessive exercise ventilation, as assessed by the slope of the regression line between expired minute ventilation and carbon dioxide output, decreased significantly from 37.2 +/- 6.7 to 33.9 +/- 5.8 (P < .001), but remained significantly higher than that in the normal subjects (27.9 +/- 3.6, P < .01). The ratio of total dead space to tidal volume and total dead space per breath during exercise decreased significantly after PTMC (P < .05). The change in excessive exercise ventilation after PTMC was correlated with the change in dead space to tidal volume ratio (r = .59). CONCLUSIONS: Significant relief of exertional dyspnea immediately after PTMC is not accompanied by an improvement in exercise capacity. A decrease in excessive ventilation due to a decrease in physiological dead space resulting from hemodynamic improvement partly contributes to the early relief of symptoms after PTMC. However, lung compliance, which was not measured in the present study, may have changed after PTMC. This change may also contribute to the symptomatic improvement.

Anaerobic Threshold↗
PubMed1993

The use of magnetic resonance imaging in diagnosing infantile neuroaxonal dystrophy.

We used MRI to investigate the brains of four children ranging from 3 to 10 years of age with infantile neuroaxonal dystrophy. T2-weighted imaging revealed characteristic findings of marked cerebellar atrophy and diffuse hyperintensity of the cerebellar cortex. At autopsy, one child had extensive astrogliosis and neuronal loss with shrinkage of the cerebellar cortex, in addition to typical widespread changes of neuroaxonal dystrophy. The characteristic hyperintensity of the cerebellar cortex on T2-weighted imaging probably is secondary to the extensive gliosis and shrinkage of the cerebellar cortex. These cerebellar findings on MRI may permit early diagnosis of infantile neuroaxonal dystrophy.

Atrophy↗
PubMed1993

High plasma concentration of myeloperoxidase in cirrhosis: a possible marker of hypersplenism.

Plasma myeloperoxidase levels in patients with cirrhosis were compared with those in patients with chronic hepatitis and healthy controls by means of a specific radioimmunoassay for myeloperoxidase. The mean concentration of plasma myeloperoxidase in cirrhotic patients (309.1 +/- 17.2 ng/ml, n = 41) was markedly higher than that in chronic hepatitis patients (222.6 +/- 17.2 ng/ml, n = 21) (p < 0.01) and normal controls (219.5 +/- 5.7 ng/ml, n = 50) (p < 0.01). Plasma myeloperoxidase showed good negative correlations with neutrocyte count (r = -0.32, p < 0.01), thrombocyte count (r = -0.40, p < 0.01), red blood cell count (r = -0.32, p < 0.01), serum albumin (r = -0.35, p < 0.01), and cholinesterase (r = -0.32, p < 0.02) and positive correlations with serum alkaline phosphatase (r = 0.49; p < 0.01) and lactate dehydrogenase (r = 0.31, p < 0.01) in patients with cirrhosis or chronic hepatitis. Among lactate dehydrogenase isozymes, a good positive correlation was seen between plasma myeloperoxidase and lactate dehydrogenase-2 (r = 0.40, p < 0.01) and lactate dehydrogenase-1 (r = 0.03, p < 0.02). Plasma myeloperoxidase was significantly higher in the cirrhotic and chronic hepatitis patients with splenomegaly (341.1 +/- 19.4 ng/ml, n = 31) than in those without splenomegaly (217.4 +/- 12.2 ng/ml, n = 29) (p < 0.01). We also examined the difference between plasma levels of myeloperoxidase in the portal and peripheral blood.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Organelle transport in cultured smooth muscle cells of the rabbit basilar artery.

Organelle transport in cultured smooth muscle cell from the rabbit basilar artery was observed. The organelles transported in the cells were moving in both centrifugal and centripetal directions. The instantaneous velocities of organelles were 0.84 +/- 0.36 micron/s in the centrifugal direction and 0.86 +/- 0.48 micron/s in the centripetal direction. The transported organelles consisted mainly of lysosomes (67.5%) and mitochondria (29.0%).

Animals↗