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Biomedical subjects

K Higashino

Publications and source records attributed to K Higashino.

At least 145 records · Page 8Linked to original sources
PubMed1993

Determination of erythrocyte aldehyde dehydrogenase activity by high-performance liquid chromatography.

An ion-paired high-performance liquid chromatographic method was developed for the determination of erythrocyte aldehyde dehydrogenase activity. This method does not require pretreatment to remove hemoglobin from the hemolysate before enzyme reaction is initiated. In addition, the advantage with this high-performance liquid chromatographic method is that erythrocyte aldehyde dehydrogenase activity can be measured using whole blood without either separation or washing of erythrocytes. Therefore, it can be easily used in the determination of erythrocyte aldehyde dehydrogenase activity, which is an indication of excess alcohol consumption.

Acetaldehyde↗
PubMed1993

In vitro oxidation of pyrazinamide and allopurinol by rat liver aldehyde oxidase.

Aldehyde oxidase was purified about 120-fold from rat liver cytosol by sequential column chromatography using diethylaminoethyl (DEAE) cellulose, Benzamidine-Sepharose 6B and gel filtration. The purified enzyme was shown as a single band with M(r) of 2.7 x 10(5) on polyacrylamide gel electrophoresis (PAGE) and M(r) of 1.35 x 10(5) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using this purified enzyme, in vitro conversion of allopurinol, pyrazinamide and pyrazinoic acid was investigated. Allopurinol and pyrazinamide were oxidized to oxypurinol and 5-hydroxy-pyrazinamide, respectively, while pyrazinoic acid, the microsomal deamidation product of pyrazinamide, was not oxidized to 5-hydroxypyrazinoic acid. The apparent Km value of the enzyme for pyrazinamide was 160 microM and that for allopurinol was 1.1 mM. On PAGE, allopurinol- or pyrazinamide-stained band was coincident with Coomassie Brilliant Blue R 250-stained band, respectively. These results suggest that aldehyde oxidase may play a role in the oxidation of allopurinol to oxypurinol and that of pyrazinamide to 5-hydroxypyrazinamide with xanthine dehydrogenase which can oxidize both allopurinol and pyrazinamide in vivo. The aldehyde oxidase may also play a major role in the oxidation of allopurinol and pyrazinamide in the subgroup of xanthinuria patients (xanthine oxidase deficiency) who can oxidize both allopurinol and pyrazinamide.

Aldehyde Oxidase↗
PubMed1993

Purification and immunohistochemical tissue localization of human xanthine oxidase.

Xanthine oxidase was purified 1600-fold from human liver cytosol. The purified enzyme was shown as a single band of 300 kDa on polyacrylamide gel electrophoresis and 150 kDa on SDS-PAGE. Using this purified enzyme, polyclonal antibody against xanthine oxidase was raised in a rabbit. On Ouchterlony's double immunodiffusion method, the raised antibody and the human liver cytosol made a precipitation line stained by activity stain and protein stain, respectively. With the raised anti-xanthine oxidase sera, the immunohistochemical localization of xanthine oxidase in human tissues was examined. Immunostaining of frozen hepatic tissue section showed that the cytoplasm of hepatocytes and endothelial lining cells were stained. In a number of other tissues, the xanthine oxidase antigen was detected only in the endothelial lining cells from heart, kidney, brain, aorta, lung and mesentery, except for the duodenal mucosa cells. A possible role for xanthine oxidase in the endothelial cells from various human tissues in the pathogenesis of reperfusion injury was suggested.

Antibody Specificity↗
PubMed1993

Charged collagen structure mediates the recognition of negatively charged macromolecules by macrophage scavenger receptors.

Macrophage scavenger receptors mediate the recognition of a wide range of negatively charged macromolecules including modified low density lipoproteins (LDL). Truncated bovine receptors lacking residues 330-342, which include the conserved lysine cluster of a collagen-like domain, were unable to degrade modified LDL in spite of their expression on the cell surface. Substitution of lysine 337 into alanine abolished the acetyl-LDL degradation and binding at 37 degrees C, but did not abolish the 4 degrees C binding. In contrast, substitution of more than 2 lysines in this region are needed to abolish the oxidized LDL degradation and 37 degrees C binding. Based on computational modeling of this domain, we propose that a "charged collagen" structure containing a lysine cluster forms a positively charged groove which specifically interacts with negatively charged ligands.

Amino Acid Sequence↗
PubMed1993

Deletion mapping of the short arm of chromosome 8 in non-small cell lung carcinoma.

Frequent losses of heterozygosity observed at several chromosomal loci in primary lung cancers have indicated the existence of several tumor suppressor genes associated with this type of cancer. We have examined loss of heterozygosity on chromosomal arm 8p in 49 cases of non-small cell lung carcinoma, using 14 restriction fragment length polymorphism markers. Of 42 cases informative with at least one marker, 21 showed allelic loss, including 15 of 32 adenocarcinomas and 5 of 9 squamous cell carcinomas. The frequency of allelic loss on 8p was similar at all clinical stages. Deletion mapping defined a single common region of deletion in these tumors within an 8 cM interval at 8p21.3-p22 flanked by the loci defined by cMSR-32 and cC18-245.

Adenocarcinoma↗
PubMed1993

Effect of ethanol ingestion on nucleotides and glycolytic intermediates in erythrocytes and purine bases in plasma and urine: acetaldehyde-induced erythrocyte purine degradation.

The effect of ethanol on nucleotides and glycolytic intermediates in erythrocytes and purine bases in plasma and urine was investigated. Ethanol ingestion (0.45 mL/kg body weight) increased plasma concentrations and urinary excretion of oxypurines (hypoxanthine and xanthine) and concentrations of adenosine monophosphate (AMP), adenosine diphosphate (ADP), and glyceraldehyde 3-phosphate+dihydroxyacetonephosphate in erythrocytes. In an in vitro incubation study using erythrocytes, acetaldehyde increased the concentrations of AMP, ADP, and glyceraldehyde 3-phosphate+dihydroxyacetonephosphate in erythrocytes as well as the concentration of hypoxanthine in the incubation medium. These results suggest that acetaldehyde (a metabolite of ethanol) induces an increase in purine degradation by erythrocytes and then contributes to the ethanol-induced enhanced purine degradation in vivo.

Acetaldehyde↗
PubMed1993

Potentiation of metastatic capacity by transforming growth factor-beta 1 gene transfection.

This study was designed to assess whether the excessive secretion of transforming growth factor-beta 1 (TGF-beta 1) by Chinese hamster ovary (CHO) cells transfected with TGF-beta 1 gene may be linked to the development of a metastatic phenotype. We observed large numbers of metastatic colonies in the lungs of nude mice inoculated with the transfected CHO cells. The tumors derived from these transfected cells demonstrated marked angiogenesis. We postulate that the overproduction of TGF-beta 1 by these tumors may participate in the metastatic progression following establishment of angiogenesis at the primary tumor site.

Animals↗
PubMed1993

Local production and localization of transforming growth factor-beta in tuberculous pleurisy.

Transforming growth factor-beta (TGF-beta) is one of the cytokines which play an immunosuppressive role in an inflammatory process. To investigate the local production of TGF-beta, we evaluated the levels of TGF-beta in tuberculous pleural effusions (TBPE) and non-tuberculous benign pleural effusions (non-TBPE) by the growth inhibition assay with Mv1Lu mink lung epithelial cells. The mean level of TGF-beta in TBPE (46.1 +/- 31.5 pM; mean +/- s.d.) was higher than in non-TBPE (21.7 +/- 12.3 pM) (P < 0.05). Although the level of interferon-gamma (IFN-gamma) in TBPE measured by ELISA was significantly higher than in non-TBPE, there was no significant difference in the levels of tumour necrosis factor-alpha (TNF-alpha) measured by ELISA between these two groups. Moreover, to elucidate localization of TGF-beta in tuberculous pleurisy, immunohistochemical studies of pleura, using the rabbit polyclonal antibody Ab39 against latent TGF-beta 1 binding protein (LTBP) were performed. Results revealed that LTBP was localized in immature fibrotic areas where infiltrations of T lymphocytes and macrophages were absent. Importantly, the major sources of LTBP in these areas were thought to be mesothelial cells and fibroblasts. LTBP was not found in granulomas and mature fibrotic areas. Our data suggest that TGF-beta in tuberculous pleurisy may play important roles for regression of granulomatous inflammation and pleural fibrosis for tissue repair.

Animals↗
PubMed1993

Studies on abnormal lipid metabolism in experimental nephrotic syndrome.

The specific lipid alterations in plasma and four different tissues, as well as the activities of plasma lecithin-cholesterol acyltransferase (LCAT) and tissue lipolytic enzymes were determined in experimental nephrotic and control rats. In nephrotic rats, the cholesterol level in the heart was significantly increased, while the kidney level was decreased. When expressed per unit protein, the cholesterol level in the adrenal was also increased. The respective triglyceride and phospholipid levels were similar in both groups, except for the significant increase in the adrenal triglyceride of nephrotic rats when expressed per unit protein. The tissue lipolytic activities were significantly reduced in the heart and adrenals of the nephrotic rats. The plasma LCAT was increased, and electron-microscopically heterogenous lipoproteins (very-low density and high-density lipoproteins) were demonstrated in the nephrotic rats. These results suggest that an excess of abnormal lipoproteins in the circulation may contribute to an increased uptake of cholesterol by circulatory organs like the heart and that an accumulation of cholesterol in the circulatory organs may accelerate atherosclerosis in nephrotic syndrome.

Animals↗
PubMed1993

Effect of lactate infusion on renal transport of purine bases and oxypurinol.

To investigate whether or not lactic acid inhibits the renal transport of oxypurines and oxypurinol, we administered physiological saline containing 0.2 mol sodium lactate to 5 normal subjects intravenously. Lactate infusion decreased the fractional clearance of uric acid, but the fractional clearances of hypoxanthine, xanthine and oxypurinol were not affected. These results suggest that uric acid and lactic acid share the renal transport system of organic acids but hypoxanthine, xanthine and oxypurinol do not. It is further suggested that allopurinol treatment is reasonable in subjects with hyperuricemia accompanied by hyperlactatemia since only the urinary excretion of uric acid and not oxypurines (hypoxanthine and xanthine) was inhibited by lactate infusion.

Adult↗
PubMed1993

Effect of DL-sodium lactate infusion on excretion of purine bases and oxypurinol.

To investigate whether or not DL-sodium lactate inhibits the renal excretion of purine bases and oxypurinol, we administered physiological saline containing 0.2 mol DL-sodium lactate to 7 normal subjects intravenously. DL-sodium lactate infusion decreased the urinary excretion and the fractional clearance of uric acid, xanthine and oxypurinol, but the fractional clearance of hypoxanthine was not affected. These results suggested that the implications of DL-sodium lactate-induced hyperuricemia must be considered in patients with gout on its long term and high dose administration, and that the implications of DL-sodium lactate-induced prolongation of half-life of oxypurinol must be considered in hyperuricemic patients treated with allopurinol. However, since the high dose and long term administration of DL-sodium lactate is clinically rare, the effect of DL-sodium lactate infusion on the urinary excretion of uric acid, xanthine and oxypurinol may not be clinically important.

Adult↗
PubMed1993

[A case of allergic bronchopulmonary candidiasis improved with steroid inhalation].

A 49-year-old woman was admitted to hospital because of productive cough and dyspnea. She had been well two months before admission, when she developed an attack of asthma. Chest roentgenogram taken on admission revealed numerous shadows of inhomogeneous density in both lungs. Laboratory findings showed leukocytosis with eosinophilia (25%), high IgE level in serum and positive RAST score to Candida albicans. A diagnosis of allergic bronchopulmonary candidiasis was made by these laboratory data and clinical course. The patient was treated successfully by oral administration of methylprednisolone and inhalation of amphotericin B, but she had a relapse of the disease on cessation of steroid medication. Inhalation of beclomethasone dipropionate and procaterol hydrochloride was commenced. Thereafter, pulmonary infiltration and clinical symptoms improved after three weeks.

Administration, Inhalation↗
PubMed1993

Xylitol-induced increase in purine degradation: a role of erythrocytes.

We administered xylitol intravenously to normal subjects to investigate the mechanism of xylitol-induced increase in the purine degradation in humans. Xylitol increased the plasma concentrations of hypoxanthine, xanthine and uric acid but decreased the blood concentration of pyruvic acid. The erythrocyte concentrations of IMP, AMP, ADP, glyceraldehyde 3-phosphate and fructose 1,6-diphosphate as well as the urinary excretion of hypoxanthine and xanthine were increased, while the erythrocyte concentration of ATP was decreased. In addition, the in vitro incubation studies using erythrocytes demonstrated that both xylitol-induced purine degradation and xylitol-induced inhibition of the conversion of glyceraldehyde 3-phosphate to 1,3-bisphosphoglycerate were protected by pyruvic acid. These results indicate that xylitol-induced impairment of glycolysis in erythrocytes contributes to the observed xylitol-induced increase in the purine degradation in the body.

Adult↗
PubMed1993

[Gene analysis of human cholinesterase variants].

People with genetic variants of cholinesterase (ChE) have been reported to have prolonged apnea with the use of myorelaxant succinylcholine. For the silent type variant ChE, two cases of mutation have been reported. In one case, the exon 2 of ChE gene was disrupted by a 342 bp insertion of Alu element. In the other case, a frame shift mutation was identified at Gly-117 (GGT-->GGAG) to create a stop codon at nucleotide 384. Dibucaine resistant ChE was examined and found to have a point mutation at nucleotide 209 (A-->G) that converted Asp-70 to Gly, and consequently reduced the affinity of ChE for choline esters. In addition, another two types of a point mutation reducing ChE activity were reported on K variant (Ala-539-->Thr) and a case of (Gly-365-->Arg) in a patient with liver cirrhosis.

Cholinesterases↗
PubMed1992

Excessive production of transforming growth-factor beta 1 can play an important role in the development of tumorigenesis by its action for angiogenesis: validity of neutralizing antibodies to block tumor growth.

Angiogenesis is an important part of tumor growth in vivo. We used the transfected Chinese hamster ovary (CHO) cells that overproduced recombinant transforming growth-factor beta 1 (TGF-beta 1) to examine the possible role of this factor in tumor growth and angiogenesis in a nude mouse model. The in-vitro proliferation of TGF-beta 1-transfected CHO cells was unaffected by the treatment of either recombinant TGF-beta 1 or an anti-TGF-beta 1 antibody. The TGF-beta 1-transfected cells grew more rapidly than the parental CHO cells when injected subcutaneously into nude mice. The tumors derived from the TGF-beta 1-transfected cells showed prominent tumor-associated angiogenesis, whereas the parental cells produced tumors without such angiogenesis. In addition, an anti-TGF-beta 1 neutralizing antibody was able to inhibit both growth and angiogenesis in the tumors derived from TGF-beta 1-transfected cells. These findings suggest that the overproduction of TGF-beta 1 by tumor cells can contribute to neovascularization and may help promote tumor development in vivo.

Animals↗
PubMed1992

An immunoreactive xanthine oxidase protein-possessing xanthinuria and her family.

The presence of immunoreactive xanthine oxidase protein was proven in a xanthinuric patient, using a polyclonal antibody against xanthine oxidase. The antibody was raised against purified human liver xanthine oxidase in a rabbit. Double immunodiffusion method demonstrated the existence of an immunologically reactive xanthine oxidase which did not possess xanthine oxidase activity. In addition, urinary excretion of oxypurines in the patient and her family was investigated. The results indicated that a brother and a sister had xanthinuria.

Adult↗
PubMed1992

Enzymatic basis of sugar structures of alpha-fetoprotein in hepatoma and hepatoblastoma cell lines: correlation with activities of alpha 1-6 fucosyltransferase and N-acetylglucosaminyltransferases III and V.

alpha-Fetoproteins (AFPs) were purified from 2 hepatoma cell lines (Hep G2 and HuH-7) and a hepatoblastoma cell line (HuH-6), and the structures of pyridylaminated (PA) derivatives of their sugar chains were analyzed by HPLC. Simultaneously, the activities of alpha 1-6 fucosyltransferase (alpha 1-6FT) and N-acetylglucosaminyltransferase III (GnT-III), IV (GnT-IV) and V (GnT-V) were assayed in these cell lines. For all 3 cell lines the major sugar chain detected was a fucosylated biantennary structure. Hep G2 cells contained a high level of GnT-V, which catalyzes the formation of a tri'-antennary structure, and in fact a substantial percentage of the AFP sugar chains in these cells had the tri'-antennary structure. alpha 1-6FT was also high, and fucosylated tri' structures were detected, which suggests that high activities of transferases affect the AFP sugar chains. In HuH-6 cells, GnT-III, which catalyzes the formation of bisecting GlcNAc, was elevated. Correspondingly, a fucosylated, bisected biantennary structure was found as a major sugar chain. In the HuH-7 cell line, the contents of bisecting GlcNAc and tri' structure were low and neither GnT-III nor GnT-V was elevated. These data indicate that the sugar structures of AFP in these cell lines correlate well with the activities of alpha 1-6 FT, GnT-III and GnT-V.

Carbohydrates↗