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S Horie

Publications and source records attributed to S Horie.

At least 217 records · Page 12Linked to original sources
PubMed1984

[Results of sputum cytology in bronchogenic carcinoma--a correlation with patient survival].

In a study of 65 of patients with bronchogenic carcinoma who had thoracotomy over a 5-year period, cytodiagnosis by 3-day consecutive sputum cytology was reported positive for malignant cells in 55.4%. Data analysis revealed that the overall cytodiagnosis correlated with clinical stage, tumor size, site of origin, topography and histologic types. From the histologic standpoint, the site of origin was significantly related to the positive cytology in patients with squamous cell carcinoma among factors influencing the results of sputum cytology. On the other hand, there was a correlation of tumor size and the positive cytology in patients with adenocarcinoma. In addition, poor prognosis related to the positive cytology in adenocarcinoma cases in terms of the relationship between the results through sputum examination and survival. The authors emphasized that sputum cytology has proven to be a valuable factor for determining prognosis, especially in patients with adenocarcinoma.

Adenocarcinoma↗
PubMed1983

Studies on the ferricytochrome a-ferrocytochrome a3-carbon monoxide complex of mammalian cytochrome oxidase. Conditions for preparation and some properties.

The conditions for the preparation of the ferricytochrome a-ferrocytochrome a3-carbon monoxide complex (a3+, a3(2)+CO) of cytochrome oxidase [EC 1.9.3.1] by the ferricyanide-reoxidation method and some properties of the prepared complex were studied. The addition of a small volume of concentrated ferricyanide solution to the dithionite-reduced and carbon monoxide-treated cytochrome oxidase preparation was required to obtain the (a3+, a3(2)+CO) spectrum showing absorption maxima at 590, 545, and 429 nm. The addition of larger volumes of ferricyanide solution, thus introducing larger amounts of oxygen into the preparation, caused decomposition of the carbon monoxide complex. A part of the added ferricyanide was immediately reduced by dithionite whereas the remainder was gradually reduced by partial oxidation product(s) of dithionite. The (a3+, a3(2)+CO) complex was stable only when excess ferricyanide remained in the reaction mixture. The formation of the (a3+, a3(2)+CO) spectrum was observed when sodium citrate, phosphate or borate buffer containing either cholate or a non-ionic detergent was employed as the solvent buffer, but not with the buffers containing sodium dodecyl sulfate (SDS) or cetyltrimethyl-ammonium bromide (CETAB). The formation was considerably inhibited by trishydroxymethyl-aminomethane(Tris)-HCl buffer. The (a3+, a3(2)+CO) spectrum appeared with maximal intensity at around pH 7. The pH-dependency of the intensity of the spectrum was not in parallel with the pH-dependent change of the polymerization state of the cytochrome oxidase preparation. On freezing to liquid nitrogen temperature, the (a3+, a3(2)+CO) complex prepared in usual solvent buffers was mostly converted to the oxidized form of cytochrome oxidase (a3+, a3(3)+. However, when prepared in the phosphate buffer, pH 8.0, containing 1.2% (w/v) sodium cholate and with 20% saturation with ammonium sulfate, the complex mostly remained unchanged after the freezing. Based on the results obtained, the stability of the juxta-heme structure of cytochrome a3 was also discussed.

Animals↗
PubMed1983

Spectrophotometric and electron spin resonance studies on the substrate interactions of ferredoxin-linked nitrite reductase from spinach.

Interactions of ferredoxin-linked nitrite reductase (NiR) from spinach with its substrate were studied by spectrophotometry and electron spin resonance (ESR) spectroscopy. Siroheme was extractable from NiR with 2.5% (W/V) trichloroacetic acid (TCA) and with acetone containing 0.01 N HCl. The addition of nitrite or sulfite to these extracts resulted in shifts of the absorption spectra of siroheme. The HCl-acetone extract showed ESR signals of symmetrical high spin heme, which disappeared on addition of nitrite. Spectral titration indicated a high affinity of extracted siroheme to nitrite and sulfite. The addition of nitrite or sulfite to protoheme dissolved in 0.01 N HCl-acetone did not cause a shift of the absorption spectrum. The extractability of siroheme with 0.01 N HCl-acetone was suppressed by the addition of nitrite to the NiR preparation. Moreover, a substrate-induced difference spectrum with peaks at about 295 and 287 nm was observed on addition of nitrite to NiR. These observations indicated an intrinsic strong affinity of siroheme to nitrite and sulfite, formation of rhombicity of siroheme by binding to the protein moiety, and also a probable conformational change of NiR on binding to the substrate. In agreement with previous reports, ESR signals of the heme-NO complex were observed with NiR in the presence of nitrite, methyl viologen (MV), and dithionite. In the present study, the same signals of similar intensity were also observed on omission of MV, under which conditions no catalytic reduction of nitrite occurred. Furthermore, the signal of the heme-NO complex was not observed when MV was replaced by spinach ferredoxin.(ABSTRACT TRUNCATED AT 250 WORDS)

Electron Spin Resonance Spectroscopy↗
PubMed1982

Changes in membrane surface properties of hepatic peroxisomes of rats under several conditions as determined by partition in aqueous polymer two-phase systems.

Changes in membrane surface properties of hepatic peroxisomes of rats under several conditions were observed by aqueous polymer two-phase systems, which contained 6% (w/w) dextran T 500, 6% (w/w) polyethyleneglycol 4000, 250 mmol sucrose/kg and various concentrations of sodium phosphate buffer. The partition of peroxisomes into the upper phase depended to a large extent on their membrane surface charge. The cross-points of peroxisomes shifted from 5.55 to 5.25 and 5.2 after the administration of clofibrate and aspirin for 2 weeks, respectively, although that of alloxan-diabetic rat peroxisomes was not altered. The hydrophobic properties of peroxisomes, examined by means of a partition containing polyethyleneglycol monostearate, were altered by diabetes and starvation, but no change occurred in rats treated with clofibrate or aspirin. In the liver of rats fed a high-fat diet, the partition of peroxisomes was the same as that of the control. These findings indicate that hypolipidemic drugs such as clofibrate and aspirin induce the proliferation of peroxisomes and lead to the alteration of the surface charge of peroxisomal membranes. Diabetes or fasting lead to an alteration mainly of the hydrophobic properties. Both changes are probably due to alteration of content and/or composition of the proteins and the phospholipids in peroxisomal membrane under the conditions used.

Animals↗
PubMed1982

Studies on the enzymatic reduction of C-nitroso compounds. V. Molecular properties of porcine heart C-nitrosoreductase and identity of this enzyme with NAD(P)H dehydrogenase.

NAD(P)H-dependent C-nitrosoreductase of porcine heart cytosol was purified 12,000-fold in the presence of NADH with an overall yield of 2.2%. The purification procedure included ammonium sulfate fractionation, gel filtration with Sephadex G-100, ion-exchange chromatography on DEAE-Sephadex A-50, hydrophobic chromatography on Octyl-Sepharose CL-4B, and gel filtration with Sephadex G-200. The purity of the preparation was approximately 90% and the molecular weight of the enzyme estimated by gel filtration was about 60,000. The purified enzyme was composed of two molecular forms, nitrosoreductases 1 and 2, having isoelectric points of 8.45 and 8.6, respectively. A significant amount of zinc was found in the preparation by X-ray fluorescence analysis. The enzyme as it was prepared was colorless, but, after oxidation with p-nitrosophenol followed by gel filtration in the absence of NADH, it showed the absorption spectrum of a flavoprotein. Spectral data indicated the presence of 1 mol of flavin per mol of the enzyme. The molecular turnover number was calculated to be 10,000 nmol p-nitrosophenol reduced to p-aminophenol per min per nmol enzyme at pH 5.8 and 22 degrees C. The activity was inhibited by p-chloromercuribenzoate by 50% at a concentration of 3 x 10(-5) M. Besides the nitrosoreductase activity, the purified preparation showed NAD(P)H-dependent menadione reductase activity. The activities were both strongly inhibited by dicumarol and markedly activated by serum albumin and by Tween 20. These results indicate the probable identity of this enzyme with soluble NAD(P)H dehydrogenase (quinone) [EC 1.6.99.2].

Alcohol Oxidoreductases↗
PubMed1981

Changes in peroxisomal fatty acid oxidation in the diabetic rat liver.

Changes in fatty acid oxidation of peroxisomes in the liver of alloxan-diabetic rats were studied. After injection of alloxan (150 mg/kg, subcutaneously), the activity of peroxisomal cyanide-insensitive beta-oxidation increased more rapidly than that of carnitine palmitoyltransferase, which was the rate-limiting step of mitochondrial beta-oxidation, and reached 3 times the control level at 7 days after the treatment. The peroxisomal beta-oxidation activity was more potent toward medium chain acyl-CoAs (C=10 and 12), though it was extremely low for shorter chain lengths. The activity of carnitine acetyltransferase increased to 2.4 times the control level and the change appeared mainly in the peroxisomal fraction. On the other hand, the activity of palmitoyltransferase increased to twice the control level, distributed mostly in the mitochondrial fraction. The activity of carnitine acyltransferase increased mainly in the peroxisomal fraction, and was higher for shorter and medium chain acyl-CoAs. These results suggest that peroxisomal fatty acid oxidation and transport of acetyl-CoA and medium chain acyl-CoA as well as NADH product in peroxisomes may be rapidly enhanced in response to the demand of organs for the urgent supply of energy from fatty acids in the diabetic condition.

Animals↗
PubMed1980

Effects of fat content in the diet on hepatic peroxisomes of the rat.

Effects of fat content in the diet on rat liver peroxisomes was examined. In the livers of rats fed for one week on the high-fat diet containing 30% fat, the cyanide-insensitive palmitoyl-CoA oxidation was accelerated to eight times that of control and the enzymic activities of catalase, carnitine acetyltransferase and carnitine palmitoyltransferase were elevated by the factors of 1.3, 5 and 2, respectively. In contrast, the activities of D-amino acid oxidase in addition to the three enzymes mentioned above were all lowered by 20% when the animals were maintained on a fat-free diet for the same period of time. It appears that the high-fat diet-induced increase in the activity of carnitine palmitoyltransferase is a result of the raised activity of this enzyme in mitochondria only while the apparent high activity reflects stimulation of carnitine acetyltransferase in all the subcellular fractions. Another notable effect of the high-fat diet was a remarkable increase in the quantity of a peroxisome-associated polypeptide which was separable by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It is noteworthy that this effect of the high-fat diet resemble that of clofibrate. If the diet was deprived of fat, however, this polypeptide species, with an estimated molecular weight of 80 000, decreased to a level slightly lower than normal. On the basis of the electron micrographic criteria, the high-fat diet provoked a marked proliferation of hepatic peroxisomes.

Animals↗
PubMed1980

Physiological role of peroxisomal beta-oxidation in liver of fasted rats.

In the livers of fasted rats, the activity of peroxisomal palmitocyl-CoA oxidation (NADH production) was increased more rapidly and markedly than that of mitochondrial carnitine palmitoyltransferase, which is the rate limiting enzyme of mitochondrial beta-oxidation. The peroxisomal oxidizing activity was about twice that of the control throughout the period of fasting (1-7 days). carnitine acetyltransferase activity was increased to a similar extent in both peroxisomes and mitochondria. A possible physiological role of liver peroxisomes may thus be as an effective supply of NADH2, acetyl residues and short and medium-length fatty acyl-CoA in the cells on the enhancement of peroxisomal beta-oxidation of the animals under starvation; these substances thus produced may be transported into the mitochondria as energy sources.

Acyl Coenzyme A↗
PubMed1980

Studies on the enzymatic reduction of C-nitroso compounds. I. Distribution of c-Nitrosoreductase activity in animal tissues and partial purification of the enzyme from porcine liver.

The subcellular distribution of NADH-p-nitrosophenol (p-NSP) reductase activity at pH 6.0 in porcine liver was studied by spectrophotometric assay. About two-thirds of the activity was found in the cytosol fraction and the pH optimum of this fraction was about 5.5. The activity at pH 5.8 of cytosol fractions from various tissues of rats, quails, frogs, carp, and scallops was also studied. All these fractions showed more or less NADH-p-NSP reductase activity but the activity of NADH-aldehyde reductase (alcohol dehydrogenase [EC 1.1.1.1]) was detected only in these from liver and a few other tissues. Supernatants from sonicated cells of Bacillus subtilis and Escherichia coli also showed C-nitrosoreductase activity but were devoid of aldehyde reductase activity. The major C-nitrosoreductase of porcine liver cytosol was purified 20- to 30-fold by fractionation with ammonium sulfate, gel filtration, and ion-exchange chromatography. The pH optimum of this preparation was 5.5 and activity was strongly inhibited by p-chloromercuribenzoate (p-CMB). The enzyme preparation was stable at 5 degrees C for at least a week in the presence of NADH at pH 8.4. High concentrations of ammonium sulfate also stabilized the enzyme. An equilibrium between monomeric and dimeric forms of the enzyme was found and the molecular weight was estimated to be about 83,000 and 160,000 daltons for the monomeric and dimeric forms, respecively. The enzyme utilized NADH almost specifically and 2 mol of NADH were consumed per mol of p-NSP reduced to p-aminophenol. Nitrosobenzene and aldehydes could also serve as the electron acceptor. The aldehyde reductase activity became concentrated roughly in parallel with the C-nitrosoreductase activity during the course of the purification and these two activities could not be separated even after further purification by 5'-AMP-Sepharose affinity chromatography. N-Nitroso compounds were not affected by this enzyme.

Alcohol Oxidoreductases↗
PubMed1980

Studies on the Enzymatic reduction of C-nitroso compounds. II. Multiple forms of liver C-nitrosoreductase and the identity with alcohol dehydrogenase.

Investigations were made of the multiplicity of the major C-nitrosoreductase in porcine liver cytosol catalyzing NADH-dependent reduction of p-nitrosophenol (p-NSP) to p-aminophenol (P-AmP). A partially purified preparation prepared by precipitation with ammonium sulfate, gel filtration with Sephadex G-100, and ion-exchange chromatography on DEAE-Sephadex A-50 showed two or more apparent Km values for p-NSP and also for NADH. This preparation could be resolved into at least four subfractions having different Km values by affinity chromatography on 5'-AMP-Sepharose, Even a more purified preparation, which was obtained from the Sephadex G-100 gel filtrate by affinity chromatography followed by ion-exchange chromatography, could be resolved into multiple subfractions by isoelectric focusing in polyacrylamide gel. All nitrosoreductase subfractions extracted from the polyacrylamide gel showed NADH-aldehyde reductase (alcohol dehydrogenase [EC 1.1.1.1]) activity and, except for a few minor subfractions, the two activities were in parallel. A commercially supplied, crystalline preparation of equine liver alcohol dehydrogenase also showed a similar multiplicity and the multiple subfractions had the both enzymatic activities, although the pattern of isoelectric focusing was different from those of the porcine liver preparations. Different heat inactivation curves were observed with various preparations, but in each preparation the curve for nitrosoreductase activity always agreed with that for aldehyde reductase activity. The nitrosoreductase preparations and the alcohol dehydrogenase preparation showed very similar pH-activity curves in catalyzing NADH-dependent reduction of p-NSP. Furthermore, ethanol inhibited the NADH-p-NSP reductase reaction competitively and p-AmP inhibited the NADH-aldehyde reductase reaction competitively. These results clearly indicate that the major C-nitrosoreductase in porcine liver was present in multiple forms having different Km values and the enzyme was identical with liver alcohol dehydrogenase.

Alcohol Oxidoreductases↗