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M Kinuta

Publications and source records attributed to M Kinuta.

49 records · Page 3Linked to original sources
PubMed1988

Bonding of nitrosobenzene and phenyl isocyanide to chelated mesoheme, hemoglobin and ferrous phthalocyanine.

Reactions of nitrosobenzene, phenyl isocyanide and their ring-substituted analogues with hemoglobin, ferrous phthalocyanine and a synthetic model compound of hemoglobin were investigated by optical, 1H-NMR and infrared spectroscopy. Complexes of chelated ferromesoheme, the model compound, with 2-methyl-, 2-ethyl, 2-isopropyl- or 2,6-disubstituted nitrosobenzene were less stable than its complex with nitrosobenzene. Formation of a complex of the model compound with 2-tert-butylnitrosobenzene was incomplete. Previous studies showed that 2,6-disubstituted nitrosobenzenes are not ligands of ferrohemoglobin. In the present work 2,6-dimethylphenyl isocyanide was found to be a ligand of ferrohemoglobin. These results are consistent with binding of the nitrogen of the nitroso group of nitrosobenzene and of the carbon of the isocyanide group of phenyl isocyanide to ferroheme. The same bonding modes of these ligands to ferrous phthalocyanine were inferred from ring-current-induced shifts in the 1H-NMR spectra of the respective complexes.

Chlorides↗
PubMed1988

Gas chromatographic determination of sulfuric acid and application to urinary sulfate.

A new gas chromatographic method for the determination of sulfate was developed. In this method, sulfate was quantitatively converted to a volatile derivative, dimethyl sulfate, by a two-step procedure. First, sulfate was converted to silver sulfate by reaction with silver oxide, and then to dimethyl sulfate by reaction with methyl iodide. The derivative was analyzed by gas chromatography. Methyl methanesulfonate was used as an internal standard. The method was applied to the determination of total urinary sulfate. Phosphate and chloride ions, which interfered with the present method, were eliminated with the use of basic magnesium carbonate and an excess of silver oxide, respectively. Recovery was over 96% when 5 to 40 mumol/ml of sulfate was added to human urine samples.

Chromatography, Gas↗
PubMed1988

[A case of remarkable regression of a colonic cancer involving metastasis to the liver as a result of FT-207 treatment].

In mid-August, 1986, a 50-year-old man underwent a detailed examination following the finding of a tumor in the upper abdominal region. The tumor was revealed to be a sigmoid colon cancer with multiple metastasis to both halves of the liver. Subsequent administration of FT-207 suppositories (750 mg X 2/day) resulted in a recognizable shrinkage of the metastatic lesions in the liver after one month, and a barium enema a month later indicated a decrease in the size of the original tumor. The pre-operative CEA value was 2,317 ng/ml, but this has reduced to 46.7 ng/ml to date March, 1987. In this report of single chemotherapy treatment with FT-207 of a sigmoid colon cancer involving metastasis to the liver, the prognosis obtained for the original and hepatic lesions has been good, and the patient's course to date healthy.

Adenocarcinoma↗
PubMed1986

Formation of aryl and aryldiazenyl complexes in reactions of arylhydrazines and aryldiazenes with a synthetic model compound of haemoprotein.

The anaerobic reaction of chelated protohaemin, a synthetic model compound of ferrihaemoglobin, with phenyldiazene produced a compound with the visible-absorption spectrum of a ferrihaemochrome. The compound reacted with CN-, which is a ligand of both ferric and ferrous porphyrins, to produce the complex of the synthetic ferrihaemoglobin with CN-. Though the spectrum of the compound formed by the addition of phenyldiazene to chelated protohaemin is characteristic of a ferric porphyrin complex, this compound reacted with both toluene-p-sulphonylmethyl isocyanide and CO, which are strong ligands of ferrous porphyrins, to produce the corresponding ferrous complexes. These ligand-binding reactions indicated that the complex of chelated protohaem with phenyldiazene can behave either as a complex of a ferric porphyrin with phenyldiazenyl anion (C6H5N = N-) or a complex of a ferrous porphyrin with phenyldiazenyl radical (C6H5N = N.). Para substituents on phenyldiazene were without effect on the formation of 4-substituted phenyldiazenyl complexes with chelated protohaem. Ortho substituents resulted in less-stable complexes. The phenyl complex of chelated protohaem was prepared by the aerobic reaction of phenylhydrazine with chelated protohaemin, and its structure was confirmed by its n.m.r. spectrum. The ligand-binding properties, n.m.r. spectrum and absorption spectrum of this complex differed from those of the phenyldiazenyl complex. The phenyl complex also was produced when the phenyldiazenyl complex was exposed to O2.

Carbon Monoxide↗
PubMed1985

Analysis of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced DNA damage in tumor cell strains from Japanese patients and demonstration of MNNG hypersensitivity of Mer xenografts in athymic nude mice.

Among 15 human tumor cell strains from Japanese patients, one strain derived from a patient with thyroid cancer showed inability to support the growth of adenovirus 5 treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). When plated on this Mer- strain, adenovirus 5 showed 3-4 times higher sensitivity to MNNG-induced killing than when plated on any of the other 14 Mer+ tumor cell strains. Biochemical analysis showed that the Mer- strain was defective in demethylation repair of O6-methylguanine produced by MNNG treatment. The sensitivities of 12 of the 15 human tumor strains, including the Mer- strain, to MNNG were compared by measuring their colony-forming abilities. All the strains tested showed the Rem- phenotype (having higher sensitivity to MNNG-produced cell killing than normal fibroblasts). The differential killing effects of MNNG on Mer- and Mer+ tumor cells under in vivo conditions were tested using the Mer+ HeLa S3 strain and its Mer- variant. Mer+ cells and Mer- cells were implanted subcutaneously into the left and right flanks, respectively, of 10 nude mice and the next day, MNNG solution (0.25 ml at 1 mg/ml) was injected into the implantation sites of eight mice. Mer- tumor cells in six of eight treated mice showed no growth and those in the other two mice did grow, but regressed after approximately 3 weeks. In contrast, Mer+ tumor cells continued to grow in all the eight mice treated, indicating that Mer- tumor cells may be selectively inactivated by suitable therapeutic regimens with appropriate methylating drugs.

Adenoviruses, Human↗
PubMed1981

Color reaction of sugars with cysteine. II. Pigment formation from sugars and biological materials.

Among carbohydrates, D-glucose, D-mannose, D-galactose, and glycogen yielded a previously described fluorescent pigment, reddish in alkaline medium and yellowish in acid, when heated with L-cysteine in hydrochloric acid solution. D-Fructose and some pentoses yielded other patients. Among tissue hydrolysates, liver, small intestine, brain, and spleen were found rich in the cysteine pigment but little or none was produced from skeletal muscle, blood, or urine. Among subfractions of rat liver cells, the microsomal fraction proved the richest source of the pigment in nmol/mg protein, though the total yield from the soluble fraction was comparable to that from the microsomal fraction. In the latter fraction, only ribosomal particles yielded the pigment; smooth membrane did not. The pigment yield from yeast was comparable to that from liver. Yield from Escherichia coli K-12 was about one-forth that from yeast.

Animals↗
PubMed1979

Cat liver cystathionase.

Cat liver cystathionase was about 300-fold purified in comparison with the supernatant of the homogenate, and the characteristics were compared with those of rat. Optimum pHs for several substrates were found to be somewhat lower, and isoelectric point remarkably lower, in cat than in rat. Molecular weight of the cat liver cystathionase was about 158,000.

Animals↗
PubMed1979

Production of S-sulfocysteine from so-called cystine disulfoxide in the presence of aspartate aminotransferase.

S-Sulfocysteine production occurred when so-called cystine disulfoxide was incubated with aspartate aminotransferase and 2-oxoglutarate. Evidence was provided indicating that the alanine sulfinic acid portion of cystine disulfoxide was transaminated and the resulting sulfinylpyruvic acid portion decomposed non-enzymatically to give S-sulfocysteine and pyruvic acid.

Aspartate Aminotransferases↗
PubMed1978

alpha-Hydroxy-beta-keto-gamma-aminobutyric acid in human urine.

A new amino acid has been isolated from the normal human urine. The chemical structure of the amino acid was determined to be alpha-hydroxy-beta-keto-gamma-aminobutyric acid based on its physical properties involving NMR, infrared and mass spectra, as well as chemical degradation and synthesis. In six healthy adults the urinary contents of the new amino acid were 3.2--4.5 mumol/24 h.

Aminobutyrates↗
PubMed1978

Mechanism of S-(carboxymethylthio)cysteine cleavage by rat liver cystathionine-gamma-lyase.

Rat liver cystathionine-gamma-lyase [L-cystathionine cysteinelyase (deaminating), EC 4.4.1.1] catalyzes the formation of pyruvic acid, ammonia, and carboxymethylhydrodisulfide from S-(carboxymethylthio)cysteine (CMTC). As judged by pyruvic acid production, the optimal pH is 8.3 in tris-HCl buffer and the Km is 2.9 mM. A possible mechanism of CMTC cleavage by cystathionase is proposed.

Animals↗
PubMed1978

Purification and characterization of mitochondrial cysteine aminotransferase from rat liver.

Cysteine aminotransferase has been purified over 300-fold from rat liver mitochondria. Transamination between L-cysteine and 2-oxoglutarate, and the reverse reaction, were observed to be catalyzed by the purified enzyme but inhibited by L-aspartate. The enzyme also catalyzed transamination of alanine, 3-sulfinic acid, aspartic acid, and cysteic acid. A new reaction assay method was devised, contributing an indication that mitochondrial cysteine aminotransferase is identical to mitochondrial aspartate aminotransferase. The latter apparently catalyzed 3 transamination reactions in the cysteine degradation process within mitochondria.

Animals↗