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T Satoh

Publications and source records attributed to T Satoh.

At least 577 records · Page 32Linked to original sources
PubMed1995

Three ATP1 genes are present on chromosome II in Saccharomyces cerevisiae.

Chromosome fragmentation, ATP1 disruption, and Southern blot analyses of total DNAs and prime clones of chromosome II showed that three identical ATP1s are present, directing from the telomere to the centromere on the 35-55 kb far from the left telomere sequence of chromosome II. That is, the coding and 5'-, 3'-non-coding regions of ATP1 are repeated 3 times at approximately 7 kb intervals. These three ATP1s are expressed, and one and two ATP1s-disrupted strains, respectively, showed ca.70 and 40% decreases in their ATPase activities and alpha subunit contents, compared to those of the wild type, DC-5 or W303-1A strain, but could grow on glycerol.

Chromosome Mapping↗
PubMed1995

Renal function in patients with high serum fluoride concentrations after prolonged sevoflurane anesthesia.

BACKGROUND: In studies of methoxyflurane-induced nephrotoxicity, renal-concentrating impairment has been observed only when serum inorganic fluoride concentrations exceed 50 microM. Prolonged sevoflurane anesthesia can result in serum inorganic fluoride concentrations in excess of 50 microM. The authors compared renal function after prolonged sevoflurane anesthesia with that after isoflurane anesthesia. In addition, they measured urinary excretion of N-acetyl-beta-glucosaminidase (NAG), a sensitive index of renal tubular damage, during the 3-day period after anesthesia. METHODS: Thirty-four healthy patients who underwent either sevoflurane (23 patients) or isoflurane (11 patients) anesthesia at a total gas flow of 61/min for orthopedic surgery scheduled to last at least 5 h were studied. At 16.5 h after cessation of anesthesia, patients were administered 10 units of vasopressin and urine was collected frequently thereafter for evaluation of urinary osmolality. In addition, urinary excretion of NAG was measured before and on days 1-3 after anesthesia. Based on whether peak fluoride concentrations exceeded 50 microM, 23 patients anesthetized with sevoflurane were assigned to a sevofluranehigh group (> 50 microM) or a sevofluranelow (< 50 microM) group. RESULTS: The eight patients in the sevofluranehigh group had a mean peak fluoride concentration of 57.5 +/- 4.3 microM. A significant, albeit weak, inverse correlation was found between peak fluoride concentration and maximal urinary osmolality after the injection of vasopressin (r = -0.42, P < 0.05). Mean maximum urinary osmolality tended to be lower in the sevofluranehigh group (681 +/- 60 mOsm/kg) than in the other two groups after administration of vasopressin, although the difference among the three groups did not quite reach a statistical significance (P = 0.068). One patient had a transient concentrating defect (maximum urinary osmolality = 390 mOsm/kg) on day 1 after anesthesia. Urinary excretion of NAG in both the sevofluranehigh and sevofluranelow groups was greater on days 2 and 3 after anesthesia than before anesthesia. The increase in urinary NAG excretion was dose related with sevoflurane, but there was no difference in results of routine laboratory renal tests on days 2 and 3 after anesthesia among the three groups. CONCLUSIONS: The authors concluded that sevoflurane anesthesia results in increased serum fluoride concentration, a tendency toward decreased maximal ability to concentrate urine, and increased excretion of NAG. However, the increase in urinary NAG excretion was not indicative of clinically significant renal damage in these patients with no preexisting renal disease.

Acetylglucosaminidase↗
PubMed1995

Plasma thrombomodulin levels in coronary sinus blood in patients with coronary artery disease.

Plasma thrombomodulin (TM) levels in coronary sinus blood were measured in 15 patients with coronary artery disease who underwent elective PTCA (group A). TM was also measured in eight patients with coronary artery disease (group B) and six patients without coronary artery disease (group C), who only underwent diagnostic coronary angiography. The baseline level was 21.6 +/- 3.4 U/ml in group A, and 21.0 +/- 4.9 in group B, and both levels were slightly higher (P < 0.05) than those in group C (15.1 +/- 3.3). In group A, the level increased to 27.5 +/- 8.3 (P < 0.01) immediately after PTCA and then returned to 22.2 +/- 5.1 by 24 h. In groups B and C, levels showed no change immediately after angiography. In group A, the percentage increase in the TM level immediately after PTCA from that before the procedure correlated with the number of balloon inflations (r = 0.76, P < 0.01). In conclusion, the plasma TM level in coronary sinus blood might indicate endothelial damage due to atherosclerotic coronary artery disease and an increase in the level after PTCA might directly indicate vascular injury by balloon inflation.

Aged↗
PubMed1995

Oxidative metabolism of bunitrolol by complementary DNA-expressed human cytochrome P450 isozymes in a human hepatoma cell line (Hep G2) using recombinant vaccinia virus.

We examined the oxidative metabolism of a beta-blocker bunitrolol (BTL) by 10 human cytochromes P450 (CYP) (1A2, 2A6, 2B6, 2C8, 2C9, 2D6, 2E1, 3A3, 3A4 or 3A5), which were individually expressed in Hep G2 cells with a vaccinia virus complementary DNA expression system. Among the 10 isozymes, only CYP2D6 and 1A2 at a substrate concentration of 5 microns, and CYP2C8 and 2C9 in addition to the two isozymes at a BTL concentration of 1 mM, exhibited detectable BTL 4-hydroxylase activities. The activities at 1 mM BTL were on the order of CYP2D6 (100% as relative activity) > CYP1A2 (86%) >> CYP2C8 and 2C9 (7-8%). Enzyme kinetic parameters of CYP2D6 were calculated to be 4.41 microns as a Km value and 0.442 nmol min-1 per nmol CYP as a Vmax value. Kinetic parameters of CYP1A2 were calculated as 295 microns and 0.411 nmol min-1 per nmol CYP for Km and Vm values, respectively. These results suggest that both CYP2D6 and 1A2 primarily catalyse BTL 4-hydroxylation, but that the former is a predominant isozyme responsible for the reaction at a low substrate concentration range of BTL in human liver.

Adrenergic beta-Antagonists↗
PubMed1995

Chlorzoxazone is metabolized by human CYP1A2 as well as by human CYP2E1.

Chlorzoxazone, a muscle-relaxing drug, is metabolized by carbon-hydroxylation at position 6. Chlorzoxazone has been suggested as an in vivo probe for CYP2E1. We studied the specificity of such a substrate using vaccinia virus expressed human P450 forms and the effect of inhibitors for chlorzoxazone metabolism by human liver microsomes. The 6-hydroxylation of chlorzoxazone was mediated by CYP1A2 as well as by CYP2E1. The Km value of CYP1A2 and CYP2E1 for the reaction was 5.69 microM and 232 microM, respectively. However, the Vmax value of CYP2E1 for the reaction was approximately 8.5-fold higher than that of CYP1A2. The CYP1A inhibitor, alpha-naphthoflavone, as well as the CYP2E1 inhibitor, diethyldithiocarbamate, decreased chlorzoxazone 6-hydroxylation at a low substrate concentration by human liver microsomes. Our results raise questions about the suitability of chlorzoxazone as an in vivo probe for hepatic CYP2E1 activity. In human liver microsomal samples, the Km = 40 microM was different from either the Km of CYP1A2 or CYP2E1. We think that this discrepancy is due to the co-expression of similar levels of CYP1A2 and CYP2E1 in human liver. Furthermore, it is suggested that the role of CYP2E1 in 6-hydroxychlorzoxazone formation at the physiological chlorzoxazone concentration of 30-60 microM is almost the same when compared to that of CYP1A2.

Benzoflavones↗
PubMed1995

A new genus of marine budding phototrophic bacteria, Rhodobium gen. nov., which includes Rhodobium orientis sp. nov. and Rhodobium marinum comb. nov.

Strains of a previously undescribed species of purple nonsulfur phototrophic bacteria were isolated from coastal seawater in Japan. These new isolates were gram-negative, motile, budding rods that contained lamellar intracytoplasmic membranes and produced pink to red cultures. Cell extracts of photosynthetic cultures exhibited absorption maxima at 377, 468, 500, 530, 591, 802, and 870 nm, indicating that bacterio-chlorophyll a and carotenoids of the spirilloxanthin series were present. The new isolates were halophilic, facultatively aerobic photoheterotrophs that grew anaerobically in the light or aerobically in the dark. Maximum growth occurred in the presence of 4 to 5% NaCl. Anaerobic growth in the dark with nitrate as a terminal electron acceptor also occurred. Various organic compounds were used as photosynthetic electron donors and carbon sources. Sulfate was used as a sulfur source. Both menaquinone 10 and ubiquinone 10 were produced; these quinones were the major quinones. A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain MB312T (T = type strain), a representative of the new phototrophs, was a member of a lineage that was distinct from members of the genus Rhodopseudomonas; Rhodopseudomonas marina was the closest relative. On the basis of the data described above, we propose the name Rhodobium orientis gen. nov., sp. nov. for the new isolates. We also propose that Rhodopseudomonas marina Imhoff 1983 should be transferred to the genus Rhodobium as Rhodobium marinum comb. nov.

Bacteria↗
PubMed1995

Walking exercise and improved neuropsychological functioning in elderly patients with cardiac disease.

OBJECTIVES: The present study examines the effects of exercise by walking on demented elderly patients with cardiac diseases. DESIGN: Walking exercise, mental activity and brain atrophy were assessed by using the number of steps. Hasegawa's dementia score and computed tomography, respectively. SETTING/SUBJECTS: Forty-six elderly patients with cardiac disease who were living in a metropolitan city. INTERVENTIONS: The Hasegawa dementia score was determined for each patient. The memory scores were used to divide the patients into four groups: normal, > 30.0; subnormal, 30.0 approximately 22.0; predementia, 21.5 approximately 10.5; and dementia, < 10.0. The walking exercises were performed every day. We also studied the ratio of the fullness of the brain (S1) to head size (S), represented as a percentage (S1/S x 100). We screened our patients for depression by means of a self-rating depression test. MAIN OUTCOME MEASURES: Walking exercise and improved mental activities. RESULTS: The mean numbers of the steps per day for the groups were 3386 +/- 676 (normal), 1008 +/- 193 (subnormal), 1597 +/- 661 (pre-dementia) and almost no walking (dementia). The mean values of the S1/S ratio for the first three groups were as follows: normal, 84.8 +/- 3.2; subnormal, 79.2 +/- 4.3; and predementia, 76.8 +/- 4.9. Only one patient was positive with regard to the depression test. CONCLUSIONS: The mental activity of elderly cardiac patients with dementia and/or brain atrophy improved with exercise from walking.

Aged↗
PubMed1995

Ceroid pigment deposition in circulating blood monocytes and T lymphocytes in Hermansky-Pudlak syndrome: an ultrastructural study.

An electron microscopic study of peripheral leukocytes obtained from a 39 year old woman with Hermansky-Pudlak syndrome was performed. Ceroid pigment granules were found within the lysosomes in 3.5% of monocytes and 5.4% of lymphocytes. Infrequently, pigment granules were also found in the parallel tubular arrays of lymphocytes. The lymphocytes containing ceroid pigment granules were confirmed to be T cells by immunoelectron microscopy. It was speculated that intralysosomal accumulation of ceroid pigment granules in Hermansky-Pudlak syndrome may be due to lysosomal dysfunction.

Adult↗
PubMed1995

[5 cases of clostridium difficile enteritis in infants].

We encountered 5 cases of Clostridium difficile enteritis that is rate in infancy. Its clinical symptoms consisted mainly of diarrhea, fever and vomiting. Also progressive abdominal enlargement was characteristically noted. Hematological examination revealed an increase in the number of leukocytes predominant with granulocytes in addition to accelerated erythrocyte sedimentation rate, an increase in alpha 2 globulin value and high LDH. On the bacteriological examination, detecting bacteria was difficult because of diarrhea being frequent and small in quantity, so bacteria were detected in only 2 out 5 cases. However, reaction to a CD latex agglutination test turned positive in all the cases during the clinical course, which was consistent with changes in the symptoms. Prognosis was good except one cases which in the symptoms. Prognosis was good except one case which had recurrence. Early diagnosis and early administration of Vancomycin are important in preventing severe complications. To that end, the CD latex agglutination test is considered useful even at present in the domain of pediatrics.

Child↗
PubMed1995

Central benzodiazepine receptor distribution after subcortical hemorrhage evaluated by means of [123I]iomazenil and SPECT.

BACKGROUND AND PURPOSE: [123I]Iomazenil is a single-photon emission computed tomography (SPECT) tracer that selectively binds to central benzodiazepine receptor in the neuron membrane. With this ligand, we studied the central benzodiazepine receptor distribution in the cortex remote from subcortical hematoma in intracerebral hemorrhage patients. METHODS: Four patients with unilateral putaminal hemorrhage and one patient with right thalamic hemorrhage were studied (mean +/- 1 SD age, 50.0 +/- 8.8 years). The initial volume of hematoma ranged from 4.3 to 31.0 mL (mean +/- 1 SD, 17.5 +/- 12.3 mL). SPECT images obtained 3 hours after intravenous administration of [123I]iomazenil (167 MBq/750 ng) were analyzed. In three patients, perfusion was evaluated with [123I]IMP. On SPECT images, the radioactivity ratio of the ipsilateral to the contralateral cerebral cortex (I/C ratio) or of the contralateral to the ipsilateral cerebellar hemisphere (C/I ratio) was measured. RESULTS: The I/C ratio for iomazenil was significantly decreased compared with unity in the temporal lobe (0.84 +/- 0.08, P < .01) and the parietal lobe (0.87 +/- 0.10, P < .05), but the C/I ratio in the cerebellum (1.00 +/- 0.03) was not. The C/I ratio for perfusion in the cerebellar cortex (0.83 +/- 0.04, P < .01) was significantly decreased compared with that in normal subjects. CONCLUSIONS: Central benzodiazepine receptor-[123I]iomazenil binding was decreased in the ipsilateral cerebral cortex remote from the subcortical hematoma. This preliminary result may facilitate further study of the potential damage of the cortical neurons remote from subcortical hematoma.

Cerebral Cortex↗
PubMed1995

Purification and characterization of glutathione-independent denitration enzyme of organic nitrate esters in rabbit hepatic cytosol.

The enzyme responsible for glutathione (GSH)-independent denitration of organic nitrate esters was purified by gel chromatography, ion-exchange chromatography and affinity chromatography from rabbit hepatic cytosol. The enzyme showed a molecular mass of 175 kDa and consisted of three subunits of 59 kDa. The enzyme exerted its maximum activities at around pH 9, when isosorbide dinitrate (ISDN) was used as substrate. The enzyme possessed a low Km value (10(-6) M) for various organic nitrate esters. The present enzyme is likely to be involved in the denitration of organic nitrate esters in conjunction with known enzymes, GSH S-transferase (GST) and cytochrome P450.

Ammonium Sulfate↗
PubMed1995

Localization and activity of adrenal carbonyl reductase during the estrous cycle.

Changes in carbonyl reductase (CR) activity towards seven substrates in adrenal glands of female rats were investigated during estrous cycle and the circadian patterns of adrenal CR activity towards seven substrates in male rats were examined. The localization of the enzyme protein in the adrenal gland was carried out by immunohistochemistry. In female rats, adrenal CR activity was lowest between 1200 and 2000 h on the day of proestrus, the phase in which a large, significant increase in ovarian steroids, gonadotropins and prolactin is observed. Immunoreactivity in the zona reticularis of the adrenal cortex to anti-adrenal CR, CR-K2, antibody on the day of proestrus was faint or negative compared with that on other days of the estrous cycle. In male rats, no major changes in adrenal CR activity were observed compared with females, although these were slight changes in all the enzyme activities. These results suggest that adrenal CR may be negatively regulated by the pituitary-adrenal axis in female rats and, in particular, on the day of proestrus.

Adrenal Glands↗
PubMed1995

Mechanism on insulin-like action of vanadyl sulfate: studies on interaction between rat adipocytes and vanadium compounds.

When rats with streptozotocin (STZ)-induced diabetes were given a daily intraperitoneal (i.p.) injection of VOSO4 (+4 oxidation state of vanadium), their serum glucose dropped from hyperglycemic level to normal level within 2d and serum free fatty acid (FFA) level also dropped to normal level. Vanadium was incorporated in most organs as well as in the adipose tissues, as detected by neutron activation analysis (NAA). The mechanism for the insulin-like action vanadium in terms of FFA release from isolated rat adipocytes was investigated: (1) Vanadyl (IV) and vanadic (III) ions normalize the FFA release in the adipocytes treated with epinephrine; (2) vanadate (V) ion treated with ascorbic acid, cysteine or glucose is effective in normalizing the FFA release but vanadate ion alone has no effect on FFA release; (3) vanadyl ion is incorporated into the adipocytes, while vanadate ion is not, as indicated by ESR spectroscopy; and (4) vanadyl ion can act on the glucose transporter, as indicated by experiments using cytochalasin B which is an inhibitor of this transporter. From these results, the normalization of both serum glucose and FFA levels by vanadyl ion was concluded to be due to the incorporation of vanadyl ion into the adipocytes, in which the metal ion acts on the glucose transporter and induces both the promotion of glucose uptake and the decrease of FFA release form peripheral adipocytes. The vanadyl state was suggested to be a possible pharmacologically active form of vanadium allowing the insulin-like action.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipocytes↗
PubMed1995

Radiofrequency catheter ablation for ventricular tachycardia with a right bundle branch block pattern and left axis deviation.

Ventricular tachycardia (VT) with right bundle branch block QRS morphology and left axis deviation originating in the inferolateral apical segment of the left ventricle was found in a 24-year-old man without overt structural heart disease. Intracardiac recordings during VT showed atrioventricular dissociation with the earliest activation at an apical inferolateral site in the left ventricle, where Purkinje fiber potentials were recorded fusing in the ventricular electrogram. Ventricular pacing was performed at this site, and yielded a QRS morphology identical to the VT. Radiofrequency current was applied and resulted in the complete elimination of VT.

Adult↗
PubMed1995

Cloning and nucleotide sequence of the gene encoding dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans.

The gene encoding dimethyl sulfoxide (DMSO) reductase, which contains a molybdenum cofactor, of the phototrophic bacterium Rhodobacter sphaeroides f. sp. denitrificans was isolated using an oligonucleotide probe, which was synthesized based on a internal amino acid sequence of the purified enzyme. The DMSO reductase gene coded for 822 amino acids (2466 base pairs, M(r) = 89,206) as a precursor form having a signal peptide of 42 amino acids. The deduced amino acid sequence had high homology with those of some enzymes containing a molybdenum cofactor: trimethyl amine N-oxide reductase (48%), biotin sulfoxide reductase (44%), and DMSO reductase (29%) of Escherichia coli.

Amino Acid Sequence↗
PubMed1995

Purification and characterization of extracellular alginate lyase from Enterobacter cloacae M-1.

An alginate lyase from the culture supernatant of Enterobacter cloacae M-1 was purified by ammonium sulfate precipitation, cation-exchange chromatography (SP-Toyopearl), and gel filtration (Ultrogel AcA44). The final preparation thus obtained showed a single band on SDS-PAGE. The purified enzyme had the molecular weight of 38,000 and 32,000 by SDS-PAGE and gel filtration, respectively. The pI of the enzyme was 8.9. The optimum pH and temperature for the enzyme reaction were around 7.8 and 30 degrees C, respectively. The enzyme was unstable on heating. EDTA completely inhibited the enzyme activity, but the activity was completely restored by the treatment with CaCl2. The enzyme was specific for poly-guluronate and produced several kinds of unsaturated oligomers from the gluluronate. This suggested that the enzyme could be classified as an endo poly-guluronate lyase.

Amino Acid Sequence↗
PubMed1995

Different mechanisms of renal Na-K-ATPase regulation by dopamine in the proximal and distal nephron.

We reported a novel intracellular mechanism of renal Na-K-ATPase regulation by dopamine (DA) in the rat cortical collecting duct (CCD), which involves stimulation of protein kinase A (PKA) and phospholipase A2 (PLA2). In the present experiments we determined whether this mechanism also operates in other nephron segments. In the medullary thick ascending limbs (MTAL), DA and other cAMP agonists inhibited Na-K-ATPase activity, an effect that was abolished by PKA inhibitor IP20, but various protein kinase C (PKC) activators did not, analogous to our previous findings in CCD. In sharp contrast, DA inhibition on Na-K-ATPase in the proximal convoluted tubule (PCT) was reproduced by PKC agonists. These effects was blocked by PKC inhibitor staurosporine, but not by IP20. Mepacrine, a PLA2 inhibitor, reversed the pump effect of all agents, and arachidonic acid (AA) produced a dose-dependent pump inhibition, in all three nephron segments. We conclude that the intracellular mechanisms of Na-K-ATPase regulation by dopamine differ in the proximal and distal nephron, as they involve stimulation of PKA in MTAL and CCD, and of PKC in PCT. These two pathways probably share a common mechanism in stimulating PLA2 and AA release in both regions of the nephron.

Animals↗