Search PubMed⌕ Search

Biomedical subjects

T Matsui

Publications and source records attributed to T Matsui.

At least 541 records · Page 30Linked to original sources
PubMed1994

Tyr-341 of the beta subunit is a major Km-determining residue of TF1-ATPase: parallel effect of its mutations on Kd(ATP) of the beta subunit and on Km(ATP) of the alpha 3 beta 3 gamma complex.

Residue Tyr-341 of the F1-ATPase beta subunit from a thermophilic Bacillus strain, PS3, was mutagenized to leucine, cysteine or alanine. Each of the mutated beta subunits was isolated and its affinity for ATP-Mg was examined by means of difference circular dichroism and differential titration calorimetry. The Kd values for ATP-Mg obtained were: beta Y341 (wild type), 0.015 mM; beta Y341L, 0.7 mM; beta Y341C and beta Y341A, > 3 mM. All the mutant beta subunits could be reconstituted into the alpha 3 beta 3 gamma complex with alpha and gamma subunits. The alpha 3 beta (mutant)3 gamma complexes hydrolyzed ATP with apparent Vmax values larger than that of the alpha 3 beta (WILD)3 gamma complex. The apparent Km values of the alpha 3 beta (mutant)3 gamma complexes increased in parallel with the Kd values for ATP-Mg of the isolated mutant beta subunits. These results indicate that residue beta Y341 is directly involved in the catalytic ATP-Mg binding and is a major Km-determining residue of F1-ATPase.

Adenosine Triphosphate↗
PubMed1994

Purification and characterization of two Ca(2+)-dependent lectins from coelomic plasma of sea cucumber, Stichopus japonicus.

Two structurally distinct lectins were purified from the coelomic plasma of holothurian, Stichopus japonicus, by affinity chromatography on a porcine stomach mucin-conjugated agarose column, gel filtration on a Superose 6 column, and ion-exchange chromatography on a HiTrap Q-FPLC. The two lectins showed apparent molecular masses of about 400 kDa (SPL-1) and 60 kDa (SPL-2) on gel filtration, but about 17 kDa on SDS-PAGE under reducing conditions. Both lectins showed hemagglutination activity toward rabbit erythrocytes in the presence of Ca2+ ions. The N-terminal amino acid sequences were highly homologous to but distinct from those of a Ca(2+)-dependent (C-type) lectin named SJL-I purified from the same species. In addition to porcine stomach mucin, the hemagglutination activity of SPL-1 was strongly inhibited by uronic acids such as galacturonic acid, and glucuronic acid, while the activity of SPL-2 was inhibited by GalNAc and galactosides. Both lectins were adsorbed on clotted coelomocytes in the presence of Ca2+ but not in the presence of inhibitory sugars or EGTA, suggesting the presence of an endogenous carbohydrate ligand(s) for plasma C-type lectins in the clot. However, coelomocyte clotting occurred normally even in the presence of inhibitory sugars, but was strongly inhibited by synthetic GRGDSP peptide or EGTA, suggesting the participation of integrin but not the lectin-carbohydrate interaction in the clotting events.

Animals↗
PubMed1994

Gastrin receptor gene expression in several human carcinomas.

Gastrin has been shown to enhance the growth of various human tumors. The present study was designed to examine the gastrin receptor gene expression in various human carcinoma cell lines and in surgically resected carcinoma tissues. By Northern blot analysis, gastrin receptor mRNA was detected in 3 out of 7 small cell lung carcinoma cell lines. Gastrin receptor mRNA was also expressed in one out of 8 colon carcinoma cell lines and 2 out of 10 colon carcinoma tissues. Moreover, one of two small cell carcinoma cell lines of the stomach clearly expressed gastrin receptor mRNA. However, none of the gastric adenocarcinoma cell lines or surgically resected gastric adenocarcinomas tested had any detectable expression of gastrin receptor gene. These findings may suggest a role of gastrin receptor in the growth and differentiation of certain human carcinomas.

Adenocarcinoma↗
PubMed1994

[Bacteremia of in-patients of the department of urology].

Thirty cases of bacteremia out of 1512 patients who had been admitted to our Department between February 1988 and June 1991 were reviewed. They consisted of 22 males and 8 females and their age ranged from 32 to 88 years (mean 62.7). 25 of the patients (83.3%) had malignant diseases of which bladder cancer (15 cases) was predominant and 5 had benign diseases. Gram positive bacteria were isolated in 18 cases (56.2%) and fungi in 4 cases (12.5%) from blood culture. Of these MRSA was most prevalent: 6 cases (18.8%), followed by S. epidermidis: 4 cases (12.5%), P. aeruginosa: 3 cases: E. faecalis: 3 cases and Corynebacterium: 3 cases (9.4%). Analysing the onset of bacteremia for each case, in three cases urinary tract infections, in one case a surgical wound infection and in one case a skin infection were prominent before the diagnosis of bacteremia. From their background, 23 cases (76.7%) were so-called compromised hosts. A total of 7 cases had died, 6 cases of bladder cancer and one case of testicular cancer, five of them were on systemic anti-cancer chemotherapy. Of those cases who expired, P. aeruginosa was isolated in two cases, Candida in two cases, MRSA in one case and E. faecium in one case, Corynebacterium in one case. It was noteworthy that in two cases where blood cultures were positive for P. aeruginosa and one case where the blood culture proved positive for Candida, drastic decrease of the peripheral leukocyte number during anti-cancer chemotherapy was seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

TGF-beta-induced macrophage colony-stimulating factor gene expression in various mesenchymal cell lines.

We report here that transforming growth factor-beta (TGF-beta) can increase the expression level of macrophage colony-stimulating factor (M-CSF) mRNA in a variety of mesenchymal cell lines derived from osteoblasts, bone marrow stromal cells, fibroblasts, and myoblasts. The M-CSF activity in the conditioned medium of mouse osteoblast-like MC3T3-E1 cells was increased by TGF-beta as well as interleukin-1 (IL-1) treatment. The increase of M-CSF mRNA expression was observed as early as 2 h after TGF-beta or IL-1 addition and was superinduced by cycloheximide treatment. Nuclear run-off assays revealed that the increase in M-CSF mRNA by TGF-beta as well as IL-1 occurred, at least in part, at the transcriptional level. Platelet-derived growth factor (PDGF) also enhanced the M-CSF production in MC3T3-E1 cells. Furthermore, TGF-beta and IL-1 distinctly induced both PDGF-A and PDGF-B chain mRNA in MC3T3-E1 with different time courses. Our present studies suggest that PDGF autocrine loop-dependent and loop-independent pathways could modulate the M-CSF production stimulated by TGF-beta or IL-1 and account for the complexity of the cytokine network involving M-CSF in vivo under various physiological and pathological conditions.

Animals↗
PubMed1994

Localization of the human cholecystokinin-B/gastrin receptor gene (CCKBR) to chromosome 11p15.5-->p15.4 by fluorescence in situ hybridization.

A human cholecystokinin-B/gastrin receptor cDNA (CCKBR) has been recently cloned and its transcriptional product has been characterized. The cDNA probe was mapped by fluorescence in situ hybridization to chromosome 11 at bands p15.5-->p15.4. The localization of this receptor gene provides a useful marker for this region of chromosome 11 permitting the identification of diseases involving the gene and interactions with other genes.

Chromosome Mapping↗
PubMed1994

Effects of new 21-aminosteroid tirilazad mesylate (U74006F) on chronic cerebral vasospasm in a "two-hemorrhage" model of beagle dogs.

The present work aimed at examining the effect of tirilazad mesylate (U74006F), a newly developed lipid peroxidation inhibitor, on the intraluminal narrowing of basilar artery subjected to subarachnoid hemorrhage (SAH) in beagle dogs. In Experiment 1, an intravenous bolus injection of either vehicle or U74006F (0.5, 1.5 and 3.0 mg/kg) was repeated every 8 hours after an induction of the first SAH until the animals were killed. A dose of 0.5 mg/kg of U74006F provided the greatest beneficial effect. In Experiment 2, an intravenous infusion of 100 ml of saline containing either vehicle or U74006F (0.3 and 1.0 mg/kg) was given in the same time schedule as in Experiment 1. Post-SAH treatment of U74006F, at a dosage of approximately 0.5 mg/kg, showed a beneficial effect by infusion as well as by bolus administration. The present study demonstrates that U74006F has an ability to prevent chronic vasospasm in the canine SAH model.

Animals↗
PubMed1994

Novel and potent aldose reductase inhibitors: 4-benzyl- and 4-(benzothiazol-2-ylmethyl)-3,4-dihydro-3-oxo-2H-1,4-benzothiazine-2-ac etic acid derivatives.

A number of 1,4-benzothiazine-2-acetic acid derivatives (1, 2 and 3) and their bioisosteres (15b, 16, 18 and 20b) were synthesized and evaluated in vitro for the ability to inhibit aldose reductase (AR) in porcine lens. The compounds which exhibited potent activity in vitro were also assayed in vivo for inhibitory activity against sorbitol accumulation in the erythrocytes, sciatic nerve and lens of streptozotocin-diabetic rats. The 4-(substituted benzothiazol-2-ylmethyl)-1,4-benzothiazine-2-acetic acid derivatives (2 and 3) showed more potent AR inhibitory activity than did the 4-(4-bromo-2-fluorobenzyl)-1,4-benzothiazine-2-acetic acid derivatives (1). 4-(4,5,7-Tri-fluorobenzothiazol-2-ylmethyl)-3,4-dihydro-3- oxo-2H-1,4-benzothiazine-2-acetic acid (2q, SPR-210) showed not only a potent AR-inhibitory activity in vitro (IC50 9.5 x 10(-9) M) but also a significant reduction in sorbitol accumulation in rat sciatic nerve (ID50 0.1 mg/kg) and lens (ID50 9.8 mg/kg). Optical resolution of the racemic SPR-210 was achieved by means of a diastereomer salt method using (-)-brucine. The biological activities of both enantiomers, (+)- and (-)-SPR-210, were comparable to that of the racemate.

Acetates↗
PubMed1994

Lanosterol oligosaccharides from the plants of the subfamily Scilloideae and their antitumor-promoter activity.

Phytochemical studies of the bulbs of Scilla peruviana, Eucomis bicolor, Chionodoxa gigantea and C. luciliae gave respectively two new and two known, four new and two known, three known, and one new and five known lanosterol oligosaccharides. The structures of the new compounds were determined from spectroscopic data. A total of 19 lanosterols, including previously isolated compounds, were examined for inhibitory activity on 12-O-tetradecanoylphorbol 13-acetate (TPA)-stimulated 32P incorporation into phospholipids of HeLa cells as the primary screening test to find new antitumor-promoter compounds.

Anticarcinogenic Agents↗
PubMed1994

[Primary culture of bovine adrenocortical cells].

The isolated bovine adrenocortical cells are prepared aseptically by the use of collagenase and deoxyribonuclease. The isolated cells are suspended in Ham F-10 medium containing 5% fetal calf serum, 10% newborn calf serum, 2.5% horse serum and antibiotics. The seeded cells are cultured at 37 degrees C in a humidified atmosphere of 5% CO2 in air. Steroidogenic activity for ACTH reached the maximum in the 2- to 3-day primary cultured cells; the maximum response to ACTH in these cells is more intense than that in freshly isolated bovine adrenocortical cells. The primary cultured cells have prostaglandin, muscarinic, ATP and beta-adrenergic receptors that are linked to steroidogenesis in addition to ACTH and aldosterone receptors. Thus primary cultured bovine adrenocortical cells are a useful tool to study these receptors and the intracellular events that are associated with the receptors. We also demonstrated that the fura 2 loaded primary cultured monolayer cells on glass cover slips provide us much more information than suspended cells in the study of intracellular Ca2+ mobilization in adrenocortical cells.

Adrenal Cortex↗
PubMed1994

Pharmacological profiles of a novel aldose reductase inhibitor, SPR-210, and its effects on streptozotocin-induced diabetic rats.

SPR-210 (2-[4-(4,5,7-trifluorobenzothiazol-2-yl)methyl-3-oxo-3,4-dihydro- 2H-1,4-benzothiazin-2-yl] acetic acid), a novel aldose reductase (AR) inhibitor, exhibited highly potent inhibition of partially purified AR from porcine lens (IC50 = 9.5 x 10(-9) M) and human placenta (IC50 = 1.0 x 10(-8) M). On the other hand, very weak inhibition by SPR-210 was observed against human placenta aldehyde reductase, which is the most closely related enzyme to AR, and against several adeninenucleotide-requiring enzymes. SPR-210 showed a noncompetitive mechanism with respect to DL-glyceraldehyde against porcine lens AR. Sorbitol accumulation in isolated human erythrocytes was effectively inhibited by SPR-210 during incubation with 50 mM glucose (IC50 = 1.6 x 10(-8) M). Oral administration of SPR-210 (1-30 mg/kg/day for 5 days) to streptozotocin-induced diabetic rats decreased the sorbitol contents in the sciatic nerve and lens (ED50 = 1.9 and 6.8 mg/kg/day, respectively). SPR-210 had higher potency in the lens than other AR inhibitors. Moreover, the deterioration in motor nerve conduction velocity in diabetic rats was ameliorated by treatment with SPR-210 (1-30 mg/kg/day) accompanying the reduction in sorbitol content in the sciatic nerve. SPR-210 induced the recovery of the delayed peak latency of oscillatory potentials (O1-O4) in the electroretinogram in diabetic rats (10 mg/kg/day). These results suggest that the specific AR inhibitor SPR-210 will be a useful therapeutic agent for preventing and improving some diabetic complications, especially diabetic neuropathy and retinopathy, and therefore, can be discriminated from other AR inhibitors.

Aldehyde Reductase↗
PubMed1994

Angiotensin I-converting enzyme inhibitory peptides in an alkaline protease hydrolyzate derived from sardine muscle.

The ACE inhibitory activity of an alkaline protease hydrolyzate from sardine muscle did not change after being treated by gastrointestinal proteases (IC50 = 0.082 mg protein/ml). Eleven new ACE inhibitory peptides, constructed with 2 to 4 amino acid residues, were isolated from the hydrolyzate. The ACE inhibitory activity of each was mostly below 100 microM of IC50 value; the maximal inhibitory activity was observed for Lys-Trp (IC50 = 1.63 microM). The isolated peptides inhibited ACE competitively, except for Met-Tyr with non-competitive inhibition. As the result of sequence homology, Arg-Val-Tyr isolated from the hydrolyzate was found in the primary structure of angiotensins I, II, and III, and of des As[1]-angiotensin I.

Amino Acid Sequence↗
PubMed1994

Characterization of monoclonal antibodies against sporadic bovine leukosis cell lines.

We report here distributions of antigens expressed on sporadic bovine leukosis (SBL) cells by a total of 38 monoclonal antibodies (mAbs) directed against three different types of SBL-cell lines, BLT2 (thymic type), BTL-PC3 (calf type) and BLS1 (skin type). Most mAbs had high reactivities with some bovine lymphoma cell lines and less reactivity with normal lymphocytes except for some peripheral blood mononuclear cells (PBM) in cattle and certain other species. They were more reactive with cultured T-cell line BTL-PC3 and B-cell lines, BL312 and KU-1, than naturally occurring lymphoid tumor cells. Among the 38 mAbs, 27 was determined the molecular weights of their recognized antigens in Western blot analyses. A mAb C419 had high reactivity with lymphoma cell lines but no reactivity with normal lymphocytes, indicating that it recognizes tumor-associated antigens of SBL.

Animals↗
PubMed1994

Muscular dystrophy of the diaphragmatic muscles in Holstein-Friesian cows.

Six Holstein-Friesian cows suffering from recurrent rumenal tympany were pathologically investigated. Macroscopical lesions associated with the clinical symptoms were confined to the diaphragmatic muscles which were pale, and stiff on palpation. Histopathological examination revealed various degenerative changes in diaphragmatic muscles as follows: variation in muscle fiber diameter, vacuolar and hyalinized degeneration of muscle fibers, fiber splitting, central core-like structures, sarcoplasmic masses and ring fibers. These characteristic features in the present cases were consistent with dystrophy of the diaphragmatic muscles in Meuse-Rhine-Yssel cattle. From these observations, it is confirmed that muscular dystrophy of the diaphragmatic muscles dose occur in Holstein-Friesian cows, although a genetic mode was not proven.

Animals↗
PubMed1994

Lymphocytic hypophysitis, pustulosis palmaris et plantaris and eosinophilia.

We describe here a unique case of lymphocytic hypophysitis accompanied by pustulosis palmaris et plantaris and eosinophilia. The patient also suffered from panhypopituitarism with hyperprolactinemia and pituitary diabetes insipidus caused by lymphocytic hypophysitis. Complications of pustulosis palmaris et plantaris and eosinophilia with lymphocytic hypophysitis have not been reported previously. In the present case, the activities of the three diseases correlated well throughout the patient's course, suggesting that a common mechanism might possibly participate in their pathogenesis.

Adult↗
PubMed1994

The role of active smooth-muscle contraction in the occurrence of chronic vasospasm in the canine two-hemorrhage model.

To evaluate the pathogenetic role of alterations in the physical properties of the arterial wall (the passive component) and of active smooth-muscle contraction (the active component) in the occurrence of chronic vasospasm, the temporal profiles of these events were examined using the canine "two-hemorrhage" model. In the in vivo study, the basilar artery was exposed via the transclival approach on Day 0, 2, 4, 7, or 14. Nicardipine, followed by the protein kinase C inhibitor H-7, then papaverine were administered in a cumulative fashion, and the change in the basilar artery diameter induced by the addition of each agent was recorded angiographically. Drug administration markedly reversed the arterial narrowing caused by chronic vasospasm. When the vasodilatory effect of each agent was compared, the dilation induced by nicardipine or papaverine progressively decreased from Day 2 to Day 7, whereas that induced by H-7 increased. The in vitro experiment using arterial segments excised from the basilar artery revealed a progressive increase in arterial stiffness from Day 2 to Day 7. Also, there was a significant decrease in the initial half-circumference of the arterial segment, which was at its maximum on Days 4 and 7. However, the alteration in the initial half-circumference was considerably less than that in the angiographic diameter following subarachnoid hemorrhage. These data indicate that the augmented spontaneous tonus of the smooth muscle plays the predominant role in the occurrence of chronic vasospasm. Thus, the involvement of the protein kinase C-mediated contractile system is strongly suggested.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗