Search PubMed⌕ Search

Biomedical subjects

E Kaneko

Publications and source records attributed to E Kaneko.

At least 145 records · Page 8Linked to original sources
PubMed1992

[Gene expression in lactate dehydrogenase-A subunit deficiency].

A 33-year-old female complained of muscle pain and stiffness after severe exercise from the age of nine. Her sister also had similar symptoms. Consanguinity was found in her parents. Neither muscle wasting nor weakness was detectable. The activity of LDH in the muscle was decreased less to than 8% of normal value. The isoenzyme pattern of the muscle LDH revealed only one band of B4. The levels of blood lactate did not rise on anaerobic exercise, while a marked increase of pyruvate was found. Northern blot analysis showed that the ratio of LDH-A transcript to beta-actin transcript in the patient was similar to that in a normal subject. RNA preparations were reverse-transcribed, amplified by a polymerase chain reaction (PCR), and separated by electrophoresis. The size of PCR product corresponding to exon 6 was decreased. The nucleotide sequence of this product was determined and a 20 bp deletion was found. This mutation results in a frame-shift translation and premature termination. The predicted incomplete LDH-A subunit contains only 259 instead of 331 amino acids. Immunofluorescence for LDH-A subunit could be seen within the cytoplasm and on the surface membrane of the muscle fibers in our patient as well as control subjects by the immunohistochemical studies. These findings suggest that LDH-A mRNA is transcribed in a truncated form and an enzymatically inactive protein is produced in the patient's muscles.

Adult↗
PubMed1992

[A case of chronic toluene poisoning with myopathic changes].

We reported a 27-year-old man, who had inhaled toluene vapor for 11 years and developed both polyneuropathy and myopathy. He gradually developed progressive muscular weakness in the limbs 2 months after the last inhalation and became nonambulant. Neurological examination revealed distal dominant muscular weakness and hypoactive deep tendon reflexes, especially in the legs. The cranial nerves were intact and neither sensory disturbances nor cerebellar signs were observed. Laboratory studies demonstrated mildly elevated serum CK value, but serum electrolytes and urinalysis were normal. Electromyogram showed a neurogenic pattern in the limbs and also a myogenic in the gastrocnemius muscle. Motor nerve conduction velocities were delayed in the limbs. The sural nerve biopsy specimens showed demyelination, myelin avoids, and axonal swelling compatible with toxic neuropathy. The muscle biopsy of the gastrocnemius revealed necrotic muscle fibers, vacuolated muscle fibers, phagocytosis, a disordered intermyofibrillary network, and small group atrophy on light microscopy. On electron microscopy, two outstanding findings were observed; the first, dilatation and proliferation of the membrane system, and the second, appearance of irregular membrano lamellar structures and vacuoles associated with abnormal membrane system. These histological findings suggest that toluene may affect directly the membrane system of muscle fibers and consequently induce rhabdomyolysis.

Adult↗
PubMed1991

Determination of aluminum in the human serum of a dialysis patient by ion-pair reversed-phase partition high-performance liquid chromatography.

An ion-pair reversed-phase partition high-performance liquid chromatography-spectrophotometric method is described for the determination of aluminum in human serum, based on its complexation with 2,2'-dihydroxyazobenzene. The chelate is separated on C18-bonded silica packing by using an aqueous methanol mobile phase containing tetrabutylammonium bromide and is detected with 0.005 AU full-scale at 510 nm. The proposed system offers a simple, sensitive, and selective method. The detection limits defined as twice the standard deviation of the blank signal, are 0.2 micrograms L-1 in pure solution and 6 micrograms L-1 in serum. The sample solution is prepared from 0.4 mL of serum after protein precipitation with hydrochloric acid and methanol. There was good agreement between the values obtained by this method and graphite furnace atomic absorption spectrophotometry. The aluminum concentrations in 121 patients on hemodialysis were 6-201 micrograms L-1.

Aluminum↗
PubMed1991

Properties of two calcium transport systems of isolated rat ileal epithelial cells: effects of Ca2+ channel modulators and membrane potential examined with fluorescent dye, fura-2.

Calcium transport systems of isolated ileal epithelial cells were investigated. The concentration of cytosolic free calcium ions, [Ca2+]i, was monitored with a fluorescent Ca2+ dye, fura-2. The fluorescence intensity ratio (I340/I380) was used as an index of [Ca2+]i. [Ca2+]i of the cells suspended in the nominally Ca(2+)-free solution was estimated at 52 +/- 3 nM. Ca2+ uptake was followed for as long as 5 min in the presence of 100-1000 microM added CaCl2. Most of the experiments were performed at 200 microM CaCl2. The Ca2+ uptake was abolished by 0.8 mM Ni2+ and 50 microM Mn2+ and partitally antagonized by 50 microM verapamil and 50 microM diltiazem but not affected by 20 microM nifedipine. The Ca2+ entry was reduced by increasing concentrations of extracellular K+ in the presence of valinomycin, suggesting a voltage-dependent nature of the uptake. On the other hand, the Ca2+ transport doubled in the presence of Bay K8644 (8 microM), a Ca2+ channel agonist. The Bay-K-8644-induced uptake was inhibited by either 10 microM nifedipine, 10 microM verapamil or 10 microM diltiazem and was relatively independent of extracellular K+ concentration. These results suggest that there are at least two distinct Ca2+ transport systems in the rat ileal epithelial cells, one resistant to organic Ca2+ channel blockers but relatively sensitive to membrane potential (basal uptake) and another inducible by Bay K 8644 and sensitive to the channel blockers but relatively independent of membrane potential.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1991

DNA-damaging, mutagenic, clastogenic and cell-cell communication inhibitory properties of gamma-oryzanol.

As a part of short-term safety assessment of gamma-Oryzanol, the genotoxic or the carcinogenic initiation activity was studied in three genetic toxicity tests and the promotion activity was studied in a cell-cell communication inhibitory test. gamma-Oryzanol showed the negative response in the bacterial DNA repair test (Rec-assay), the bacterial reverse mutation tests (Ames test) and the rat bone marrow chromosome aberration test. Also, gamma-Oryzanol showed the negative response in the metabolic cooperation inhibition test using Chinese hamster V79 cells.

Animals↗
PubMed1991

Gastrointestinal serotonin: depletion due to tetrahydrobiopterin deficiency induced by 2,4-diamino-6-hydroxypyrimidine administration.

To study the role of serotonin in gastrointestinal function in mice, a peripheral deficiency was induced by administration of 2,4-diamino-6-hydroxypyrimidine, an inhibitor of tetrahydrobiopterin (6-[dihydroxypropyl-(L-erthro)-5,6,7,8,-tetrahydropterin) (BH4) biosynthesis. BH4 is an essential cofactor for tryptophan hydroxylase, the rate limiting enzyme in the biosynthesis of serotonin. When 2,4-diamino-6-hydroxypyrimidine (DAHP) was administered for 4 days at the dose of 3 g/kg/day, serotonin decreased in the duodenum and colon to approximately 46 and 40% of the control levels, respectively. These mice showed visual signs of gastrointestinal dysfunction in addition to a remarkable decrease in uptake of a p.o. glucose load. The decrease in serotonin was prevented and prevention of the apparent dysfunction of digestive tract was observed by simultaneous administration of (6R)BH4. Serotonin levels in the brain and blood were also decreased by treatment with p-chlorophenylalanine, an irreversible inhibitor of tryptophan hydroxylase. In contrast, DAHP had no effect on brain serotonin levels, presumably due to poor brain penetration. DAHP caused a rapid decrease (T1/2 of less than 12 hr) in the BH4 levels in all tissues examined, except in the brain. The BH4 level returned to within the normal range less than 24 hr after cessation of the administration of DAHP, a finding which suggests that the BH4 level is in a dynamic steady state maintained by rapid local biosynthesis. Thus, the local biosynthesis of BH4 supports normal digestive functions, presumably by controlling normal serotonin biosynthesis.

5-Hydroxytryptophan↗
PubMed1990

Carbachol-induced potentiation and inhibition of acid secretion by guinea pig gastric gland.

The effects of muscarinic ligands on acid secretion were examined by estimating the accumulation of [14C]aminopyrine in gastric glands isolated from guinea pigs. The accumulation of [14C]aminopyrine in the presence of 0.1 mM histamine was potentiated by 1 microM carbachol but suppressed by 1 mM. These two effects of carbachol were abolished by atropine, pirenzepine and AF-DX 116. Assuming that the binding of carbachol to one site (Site 1) increases [14C]aminopyrine accumulation but its binding to the other site (Site 2) reduces [14C]aminopyrine accumulation, we analysed the dose-response curves for the carbachol effects in the absence and presence of different concentrations of atropine, pirenzepine and AF-DX 116. The dissociation constants determined for these ligands at Sites 1 and 2 were as follows: carbachol, 0.28 and 7.1 microM; atropine, 0.28 and 0.54 nM; pirenzepine, 45 and 560 nM; and AF-DX 116, 380 and 4400 nM, respectively. The binding of [3H]N-methylscopolamine to the gastric glands indicated the presence of two populations of binding sites with different affinities for the above ligands, other than atropine. The apparent dissociation constants, which were estimated by analysing the displacement curves for [3H]N-methylscopolamine binding, were as follows: carbachol, 0.18 microM (10%) and 31 microM (90%); atropine, 1.24 nM; pirenzepine, 15 nM (16%) and 220 nM (84%); and AF-DX 116, 370 nM (10%) and 2970 nM (90%). These results suggest that there are two kinds of muscarinic acetylcholine receptors in the guinea pig gastric gland, one potentiating and the other inhibiting the acid secretion induced by histamine.

Aminopyrine↗
PubMed1990

[Assay of serum collagen markers in chronic liver diseases and liver cancer].

In order to identify the most useful marker to diagnose hepatic fibrosis, type III procollagen peptide (P-III-P), laminin P1, and prolyl-hydroxylase (PH) in sera obtained from patients with liver diseases were simultaneously measured and compared with histological features of chronic hepatitis and with tumor size estimated on abdominal CT scan. Further more, the diagnostic accuracy of these markers was evaluated by using discriminant analysis. P-III-P and laminin P1 were closely correlated with the activity of chronic hepatitis. These two markers most accurately discriminated between the compensated stage of liver cirrhosis and the decompensated stage, and between liver cirrhosis and hepatocellular carcinoma. Laminin P1 was found to most clearly distinguish chronic hepatitis from liver cirrhosis. P-III-P was significantly correlated with the size of hepatocellular carcinoma. However, PH failed to discriminate among liver diseases, and showed no significant correlation with a liver tumor size. And none of the markers examined were correlated with a degree of hepatic fibrosis. From these results, the analysis of both serum P-III-P and laminin P1 is a useful approach to evaluate hepatic collagen metabolism.

Adult↗
PubMed1990

[The effect of modified sham-feeding on gastrin-stimulated gastric secretion in patient with duodenal ulcer].

Patients with duodenal ulcer were classified into responders to H2-receptor antagonist and non-responders in whom duodenal ulcer did not heal within three months with the antagonist. In these patients and healthy controls, modified sham-feeding (MSF) test was performed to elucidate the pathophysiological differences between these groups, especially vagal activity of acid output. After tetragastrin 4 micrograms/kg/hr infusion for one hour, MSF was superimposed to the infusion (G + MSF). The acid output of non-responders (8 cases) and controls (8 cases) significantly increased in G + MSF. On the other hand, the acid output of responders (6 cases) significantly decreased. The acid output of non-responders in G + MSF was also significantly higher than that of controls. The results suggest that vagal activity of non-responders is higher than responders, and that there is disturbance of inhibitory mechanism in vagal system.

Adult↗
PubMed1989

Gastric acid secretion stimulated by modified sham-feeding, and the effects of histamine H2-antagonist and anti-muscarinic agent in patients with duodenal ulcer.

Patients with duodenal ulcer (DU) were classified into responders to H2-antagonist and non-responders in whom DU did not heal within 3 months with the antagonist. In these patients and healthy controls, a modified sham-feeding (MSF) test was performed to elucidate the pathogenesis of resistance to H2-antagonist. By MSF stimulation, gastric acid secretion significantly increased in all subjects. The mean acid output by MSF amounted to about 52 of the tetra-gastrin maximum in controls (12 cases), 46% in responders (12 cases) and 72% in non-responders (14 cases). The mean acid output in non-responders was significantly higher than in controls under baseline conditions, MSF and gastrin stimulations, but was higher than in responders during MSF stimulation. The effects of H2-antagonist (cimetidine 1mg/kg/h), anti-muscarinic agent (pirenzepine 0.3mg/kg/h), or both on the acid secretion were examined on non-responders (6 cases), responders (6 cases) and healthy controls (6 cases). The acid secretion stimulated by MSF was significantly inhibited by pirenzepine in responders and controls, but not in non-responders. With cimetidine, the acid output was significantly inhibited in all groups, but was still higher in non-responders than in controls and responders, indicating that the reduction of acid output by a H2-antagonist is significantly less in non-responders than in other groups. The combined use of pirenzepine and cimetidine almost completely inhibited the acid output in all groups. These data suggest that the vagal activity in non-responders to H2-antagonist is higher than in responders and healthy subjects, and H2-antagonist combined with anti-muscarinic agent is more effective in reducing the gastric acid secretion in non-responders.

Adult↗
PubMed1989

Natural history of duodenal ulcer detected by the gastric mass surveys in men over 40 years of age.

In a gastric mass survey with photofluorography performed on 10,605 male office workers over 40 years of age, 456 cases of duodenal ulcer (4.3%) were detected. These cases were scheduled to be followed up every 6 months with endoscopy and without any anti-ulcer drugs. Two hundred and seventy-six of the cases, including 169 cases with craters and 107 cases with scars, were followed up for 2 years. Forty-one of 169 craters (24.3%) had healed, and 21 of 107 scars (19.6%) had relapsed at 6 months. At 24 months 36 of 169 craters (21.3%) had healed, and 31 of 107 scars (29.0%) had relapsed. Sixty-four and a half per cent of the ulcers that showed crater at entry remained at the crater stage, and 62.6% of ulcer scars at entry remained healed at every endoscopy during the trial period. With regard to the cases' background, cigarette smoking adversely affected the natural history of the duodenal ulcer. However, years after onset, previous treatment, history of overt bleeding, and alcohol and coffee consumption did not affect the present ulcer activity.

Adult↗
PubMed1989

[A case of Zollinger-Ellison syndrome successfully treated with an H+-K+ ATPase inhibitor].

A case of Zollinger-Ellison syndromes in a fifty year-old male that was successfully treated with a H+-K+ ATPase inhibitor (Omeprazol) is reported. The patient underwent a partial gastrectomy in 1984, but had been suffering from multiple refractory stomal and jejunal ulcers after the operation. In 1987, hypergastrinemia (760 pg/ml) was detected, and the presence of gastrinomas in the pancreatic head accompanied by a multiple liver metastasis was subsequently confirmed by CT-angiography and by the gastrin level detected in percutaneous, transhepatic, portal venous samples. A secretin provocation test proved to be negative, and the ulcers resisted the H2-receptor antagonists, but the patient was successfully cured shortly after the administration of an H+-K+ ATPase inhibitor.

Adenosine Triphosphatases↗
PubMed1989

[Detection of gut hormone mRNAs by synthetic DNA probes in gut hormone producing tissues].

Synthetic DNA probes were tested as hybridization probes for detecting gut hormone mRNAs. When 4 gut hormones, including gastrin, somatostatin, gastrin-releasing peptide and calcitonin were examined, these probes were shown to be useful for mRNA detection in the tissues producing respective hormones. It was also revealed that there was a good correlation between the concentration of peptides determined by radioimmunoassay and the amounts of mRNAs. This methodology was applied for multiple gut hormone producing tumor with the aim to elucidate the mechanisms responsible for this phenomenon, and demonstrated that the tumor expressed a large amount of mature mRNAs encoding respective hormones. These results indicate that increase of mRNA production is one of the mechanism responsible for multiple gut hormones production by tumor.

Blotting, Northern↗