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T Matsubara

Publications and source records attributed to T Matsubara.

At least 19 recordsLinked to original sources
PubMed1995

A novel Ca2+/calmodulin-dependent protein kinase lacking autophosphorylation activity in the rabbit heart.

We report the discovery, semi-purification and characterization of a novel Ca2+/calmodulin-dependent protein kinase (peak I kinase) using syntide 2 as a substrate from the rabbit heart. In the study of dependence of peak I kinase on the concentration of calmodulin, half-maximal activation was obtained at approx. 2.0 x 10(-7) M calmodulin. Peak I kinase did not undergo autophosphorylation. This kinase phosphorylates the synthetic peptides such as syntide 2, autocamtide-2, site 3 in a Ca2+/CaM-dependent manner, but not myosin light chain-peptide, gamma-peptide, and cAMP Response Element Binding Protein (CREB) peptide. Elongation Factor-2, alpha-casein and histone-IIIs were not phosphorylated. These data indicate that this CaM kinase is different from other identified Ca2+/calmodulin-dependent protein kinases and therefore constitutes a novel protein kinase.

Animals↗
PubMed1995

A new cytochrome P450 form belonging to the CYP2D in dog liver microsomes: purification, cDNA cloning, and enzyme characterization.

A new form of cytochrome P450 (P450 DUT2) was purified from untreated male dog liver microsomes. The final preparation (a specific content of 19.1 nmol P450/mg protein) showed a single band with an apparent monomeric molecular weight of 50,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but was further separated into two apoproteins (P450 DUT2a and P450 DUT2b) by reverse-phase HPLC. Both proteins had identical NH2-terminal amino acid sequences, but the first three amino acids of P450 DUT2b were truncated in P450 DUT2a. Purified P450 DUT2 showed 5 to 18 times higher catalytic activities than did hepatic microsomes toward desipramine, metoprolol, and dextromethorphan. These activities in dog liver microsomes were strongly inhibited by anti-P450 DUT2-IgG. A 1.7-kilobase pair cDNA (cDUT2) encoding a male dog liver P450 of 500 amino acid residues (molecular weight 56,400) was isolated and sequenced. The first 35 NH2-terminal amino acid sequence of P450 DUT2b coincided with the deduced amino acid sequence of cDUT2 at 2-36. The deduced total amino acid sequence of cDUT2 shared high similarity with the reported 2D forms (with 2D6, 74.6%; 2D14, 75.4%; 2D1, 65.4%; and 2D9, 63.6%). Moreover, the expressed P450 DUT2 in COS-7 cells had catalytic activities similar to those of purified P450 DUT2. Therefore, this paper is the first report about dog CYP2D. Furthermore, Northern and Western blot analyses indicated that the expressed levels of mRNA and protein were almost equal between male and female dogs. Western blot analysis suggested that P450 DUT2 is a constitutive and major (approximately 20% of the total P450) form, indicating that the 2D subfamily P450 in dog liver is quite unique from CYP2D members of other species.

Amino Acid Sequence↗
PubMed1995

Preoperative assessment of lymph nodes in the prediction of disease spread and outcome in cancer of the thoracic oesophagus.

Prospective assessment of lymph node status, based on the findings of computed tomography, external ultrasonography and palpation, was compared with clinical results in 179 patients who underwent oesophagectomy with systematic node dissection. Preoperative findings for each node group were classified into four grades: involvement not suspected (-); possible involvement (+/-); probable involvement (+); and definite involvement (++). When only (++) or (+) assessment was categorized as positive, the specificity was more than 94 per cent, although the sensitivity was less than 40 per cent. The preoperative assessment correlated significantly with the incidence of node involvement (P < 0.02), the degree of lymphatic invasion (P < 0.0001) and outcome after operation. For patients with all nodes assessed as (-), the 5-year survival rate was 70 per cent, compared with 26 per cent for those with nodes assessed as (++), P = 0.001. Preoperative assessment provided useful information on nodal status.

Carcinoma, Squamous Cell↗
PubMed1995

Vascular complications in patients with aldosterone producing adenoma in Japan: comparative study with essential hypertension. The Research Committee of Disorders of Adrenal Hormones in Japan.

The incidence of vascular complications in 224 patients with aldosterone-producing adenoma (APA) which was proven on adrenal surgery, was compared to that in 224 sex- and age-matched patients with essential hypertension (EHT). The incidence of cerebral hemorrhage was significantly higher (p < 0.05) in the patients with APA when compared to the EHT group. On the other hand, the incidence of myocardial infarction and/or congestive heart failure in the APA group was lower, although this difference did not reach statistical significance. Diastolic blood pressure in the APA group was significantly higher (p < 0.001) in the EHT group. However, a significant difference in diastolic blood pressure was not detected between the APA groups with and without vascular complications, whereas in the EHT group diastolic blood pressure was significantly higher (p < 0.001) in cases with vascular complications as compared to those without complications. As a possible factor contributing to the higher incidence of cerebral hemorrhage in the APA group, proteinuria was suggested. It was recommended that patients with primary aldosteronism should undergo operation when localization of the APA is established.

Adenoma↗
PubMed1995

Can esophagectomy cure cancer of the thoracic esophagus involving the major airways?

To evaluate the effects of aggressive operation for esophageal cancer invading the trachea and main bronchi, we investigated retrospectively 62 patients with proven tracheobronchial involvement who underwent thoracotomy for esophagectomy between 1973 and 1993. We operated unless the tumor was assessed to be definitely unresectable. Esophagectomy was possible in 55 patients, and the resectability rate was 95% after preoperative computed tomography and bronchoscopy became routine. After esophagectomy, no residual cancer lesion was recognizable macroscopically in 53% of patients. The hospital mortality rate in esophagectomy cases was 7% in the past 8 years. The outcome in patients who underwent curative resection was significantly favorable (p < 0.0001), and the 2-year survival was 51%. The patients with nonresectable cancer all died within 6 months compared with a 23% 1-year survival rate for palliative esophagectomy cases (p < 0.006). Among patients with tracheobronchial involvement assessed as resectable on computed tomography and bronchoscopy, a considerable proportion benefited from aggressive therapy with esophagectomy. The possibility of complete cure was high, especially when the cancer responded well to preoperative therapy and no lymph nodes were involved.

Adult↗
PubMed1995

Pressor response induced by the hippocampal administration of neostigmine is suppressed by M1 muscarinic antagonist.

We investigated the roles played by three muscarinic receptors (M1, M2, and M3) in the pressor response with bradycardia that followed the injection of neostigmine (5 x 10(-8) mol) into the hippocampus of anesthetized rats. These changes were blocked by the co-administration of methylatropine (5 x 10(-8) mol). The intrahippocampal injection of pirenzepine (M1 antagonist) (5 x 10(-9) - 5 x 10(-7) mol) suppressed the neostigmine-induced pressor response dose-dependently. However injection of gallamine (M2 antagonist) (5 x 10(-8) - 5 x 10(-7) mol) and of 4-DAMP (M1 and M3 antagonist) (5 x 10(-8) - 5 x 10(-7) mol) did not suppress this hypertensive response. These findings suggest that the neostigmine-induced pressor response with bradycardia is mediated through the M1 muscarinic receptor subtype.

Animals↗
PubMed1995

Comparison of 99Tcm-pyrophosphate, 201T1 perfusion, 123I-labelled methyl-branched fatty acid and sympathetic imaging in acute coronary syndrome.

Among a group of patients (n = 15) with acute coronary syndrome, the results of using two new myocardial radiopharmaceuticals--123I-labelled 15-(p-iodo-phenyl)-3,R,S-methylpentadecanoic acid (BMIPP) and 123I-meta-iodobenzyl guanidine (MIBG)--were compared with dual 201Tl/99Tcm-pyrophosphate (Tl-PYP) imaging using single photon emission tomography (SPET). Defect scores were evaluated on a segment-by-segment basis for a total of 270 segments. For the 201Tl, BMIPP, and early and delayed MIBG studies, the mean (+/- S.D.) sums of defect scores were 9 +/- 8, 18 +/- 9, 22 +/- 12 and 29 +/- 9, respectively, revealing significantly higher scores for BMIPP and MIBG than 201Tl (P < 0.005). This was the case irrespective of various functional conditions, such as successful recanalization, failure of coronary angioplasty or restenosis. The culprit coronary artery was best identified using BMIPP, while MIBG SPET showed the most extensive defects. Normal perfusion with decreased BMIPP and MIBG uptake was frequently observed and associated with hypokinesis. 123I-BMIPP and MIBG are more sensitive for the detection of damaged myocardium, and the difference between perfusion and metabolism seems to reflect myocardial stunning.

3-Iodobenzylguanidine↗
PubMed1995

Mutagenicity of bile and pancreatic juice from patients with pancreatico-biliary maljunction.

We attempted to detect mutagenic activity in bile and pancreatic juice from patients with biliary tract disease using the spore rec assay and wild (H17) and mutant (M45) strains. Three bile samples out of 5 obtained from patients with pancreatico-biliary maljunction showed positive reaction in the spore rec assay, and all contained a high level of amylase activity, while 300 microliters of bile samples obtained from 10 control patients without pancreatico-biliary maljunction did not show any positive reaction. Moreover, 300 microliters of the in vitro mixture of bile with an equal volume of pancreatic juice also showed a positive reaction after treatment for 12 days at 37 degrees C or for 10 min at 100 degrees C, suggesting that they were very stable and long-acting in vivo. These data suggest that possible mutagens might be formed by the mixing of bile with pancreatic juice regurgitated into the biliary tract, and that there might be a relationship to biliary tract cancer which often accompanies pancreatico-biliary maljunction.

Amylases↗
PubMed1995

[Dye leakage from choroidal neovascularization with indocyanine green angiography].

The ultrastructure of experimentally induced choroidal neovascularization was studied in correlation with dye leakage in indocyanine green (ICG) infrared fluorescence angiography. Newly formed vessels which demonstrated leakage of ICG extended into the subretinal space without enclosure of retinal pigment epithelium (RPE), and the endothelial cells were immature. Choroidal neovascularization which did not demonstrate leakage of ICG was enclosed by RPE without retinal detachment, and the endothelial cells were mature. The newly formed vessels with immature endothelium in the subretinal space that were covered with multiple layers of RPE demonstrated no leakage. These results show that ICG leaks form choroidal neovascularization which has immature vessels that are not enclosed by RPE and that extend into the subretinal space.

Animals↗
PubMed1995

[Circularity index of left ventricular shape in the assessment of heart disease].

Left ventricular volume and ejection fraction obtained by cineangiography are useful to evaluate global left ventricular function in humans. Left ventriculography provides evidence of the effect of coronary artery stenosis on regional wall motion in patients with coronary artery disease. Changes in left ventricular shape are also found in various heart diseases. The left ventricular cavity is normally ellipsoid in shape, but becomes flat in hypertrophic cardiomyopathy, globular in dilated cardiomyopathy, and aneurysmal in some patients with myocardial infarction. This study developed a new method to quantify regional and global left ventricular shape. Regional circularity index (RCI) was defined as GD divided by r (GD = distance from each 5-degree endocardial margin to the center of gravity, r = radius of the circle equal to left ventricular area). The global circularity index (GCI) was derived from the sum of magnitude of RCI-1. The end-systolic GCI was related to end-systolic left ventricular wall stress (r = 0.71, p < 0.001). The change in GCI during systole was related to left ventricular ejection fraction (r = 0.79, p < 0.001). In severe cases of dilated cardiomyopathy, the left ventricle became more spherical during ejection. End-systolic left ventricular moment around the minor axis had a good correlation with left ventricular ejection fraction (r = 0.81, p < 0.001). Quantification of regional and global left ventricular shape can be used to estimate left ventricular wall stress from left ventricular shape. Left ventricular shape change during systole and the moment around the left ventricular short axis contributes to left ventricular ejection.

Angiocardiography↗
PubMed1995

[Local spread of carcinoma of the esophagus by perineural invasion].

For clarification of the clinico-pathological features of carcinoma of the esophagus by perineural invasion (pni), 107 resected specimens were histologically examined. A correlation between pni and other findings, including clinical results, was sought. Pni was found in 31 patients (29.0%). It was found in no cases without adventitial cancerous invasion, at 26.3% in a1, 36.5% in a2 and 66.7% in a3. Pni would thus appear to be closely correlated with the depth of invasion. It also showed correlation with lymph-canal invasion but not with venous invasion or lymph node metastasis. Pni positivity was the same regardless of patient's age and sex, as well as tumor size, location and histological differentiation. In patients who had undergone preoperative radiotherapy, lymph-canal and venous invasion were noted to have markedly decreased but not pni. Curative resection was carried out in 57.9% of the pni negative patients and in 32.3% of the pni positive. Local recurrence was observed in 30.0% of pni positive and only 4.5% of negative cases. The cumulative survival rate was not significantly less in positive compared to negative patients.

Adult↗
PubMed1994

Polar lipids of a non-alkaliphilic extremely halophilic archaebacterium strain 172: a novel bis-sulfated glycolipid.

Extremely halophilic archaebacteria which require high salt concentrations for growth and survival contain glycerol diether analogues of phospholipids and sulfated glycolipids as major membrane polar lipids. A non-alkaliphilic, non-pigmented rod-shaped extreme halophile, isolated from sea sand in Japan and designated 'strain 172', was found to contain two phospholipids, phosphatidylglycerol (PG) and phosphatidylglyceromethylphosphate (PGP-Me), derived from both C20-C20- and C20-C25-glycerol diethers, and a novel major glycolipid (designated SGL-X). This glycolipid has been identified as a bis-sulfated diglycosyl C20-C20- or C20-C25-glycerol diether, on the basis of its TLC mobility, positive-staining behavior with sugar and sulfate-staining reagents, its mole ratio sulfate/glycolipid = 2.2, and by spectrometric analysis (IR and FAB-MS) of the intact and the desulfated SGL-X. The sugars were identified as mannose and glucose, after acid hydrolysis of SGL-X, by paper chromatography of the free sugars and GC-MS of the derivatized sugars (alditol acetates). Permethylation analysis and 1H- and 13C-NMR analysis established the position and configuration of the sugar linkages and the positions of the sulfate groups. The final structure of SGL-X (now designated S2-DGD-1) is proposed to be: 2,3-diphytanyl- or phytanyl-sesterterpenyl-1-[2,6-(HSO3)2-alpha-Manp-1--> 2- Glcp]-sn-glycerol. This lipid is the first bis-sulfated glycolipid to be reported in extremely halophilic archaebacteria, and is the first in the biosphere that possesses two sulfate groups attached to the same monosaccaride.

Archaea↗
PubMed1994

The involvement of the stimulatory G protein in sexual dimorphism of beta-adrenergic receptor-mediated functions in rat liver.

In rat hepatocytes, beta-adrenergic receptor (beta-AR)-mediated cAMP generation was found to be higher in the female than in the male. As compared to the male, the number of beta-AR, detected by [125I]iodocyanopindolol, was elevated in the female. In agonist competition experiments, the proportion of beta-AR in the high-affinity state was promoted in the female than in the male. The alpha subunit of the stimulatory G protein (Gs alpha) was quantified using ADP-ribosylation catalyzed by cholera toxin. The amount of Gs alpha, both small, 42 kDa (Gs alpha S), and large, 47 kDa (Gs alpha L), forms increased in parallel with enhancement of catecholamine-sensitive adenylate cyclase activity in the female. The female showed a disproportionate increase in Gs alpha L, which is preferentially coupled to beta-AR, compared with Gs alpha S. In addition, 17 beta-estradiol facilitated isoproterenol-induced cAMP generation in both male and female rats, whereas castration or testosterone had no effect on this response. It is proposed that the cellular sites for sexual dimorphism in hepatic beta-adrenergic functions are the coupling state of beta-AR to Gs and the amount of Gs alpha as well as the level of beta-AR.

Adrenergic beta-Antagonists↗