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T Matsuki

Publications and source records attributed to T Matsuki.

106 records · Page 6Linked to original sources
PubMed1981

Age-dependent decay of cytochrome b5 and cytochrome b5 reductase in human erythrocytes.

Age-dependent decrease in cytochrome b5 was observed in erythrocytes from both a normal person and a patient with hereditary methaemoglobinaemia without neurological symptoms. With aging, concentrations of cytochrome b5 in erythrocytes from the patient were almost the same as those in the control. Age-dependent decrease in cytochrome b5 reductase activity in the control erythrocytes was also shown; however, the reductase activity was very low in erythrocytes from the patient over the whole age range. Our studies show that methaemoglobin content of erythrocytes seems to be dependent on the content of cytochrome b5 in the cells, both in the control subject and in the patient.

Cytochrome Reductases↗
PubMed1981

Congenital methaemoglobinaemia due to NADH methaemoglobin reductase deficiency: successful treatment with oral riboflavin.

A Japanese family with congenital methaemoglobinaemia is described. The family pedigree was compatible with autosomal recessive type of inheritance. The increased methaemoglobin concentration was ascribed to the red cell NADH diaphorase deficiency associated with the almost complete lack of one of the two peaks of the diaphorase activity as separated by DEAE Sephadex column chromatography. The NADH diaphorase and NADH methaemoglobin reductase deficiency was limited to the red cells. The methaemoglobin content in the blood of the propositus was 17.8% and isoelectric focusing analysis on a polyacrylamide gel plate showed that the haemoglobin consisted of 65.2% oxyhaemoglobin (alpha 2+ beta 2+)2, 29.6% half-oxidized forms, 20.9% (alpha 3+ beta 2+)2 and 8.7% (alpha 2+ beta 3+)2, and 3% full-oxidized methaemoglobin (alpha 3+ beta 3+)2. Oral administration of riboflavin 120 mg/d resulted in a gradual but significant decrease in the level of the met-form haemoglobins in parallel with a gradual increase in the red cell flavin content. Riboflavin is considered to be effective by activating the NADPH diaphorase (NADPH flavin reductase) system and appears to be useful for the treatment of congenital methaemoglobinaemia.

Administration, Oral↗
PubMed1980

NADH-cytochrome b5 reductase in platelets and leukocytes with special reference to normal levels and to levels in carriers of hereditary methemoglobinemia with or without neurological symptoms.

Normal levels of NADH-cytochrome b5 reductase activity in platelets, lymphocytes and granulocytes were determined. The homogenate of each cell was treated with Triton X-100 after incubation with lipoprotein lipase. The reductase was extracted very well from the cells by this treatment. Moreover, the assay of the reductase activity in the cells became accurate and reproducible by the treatment. The reductase level of each cell was also determined in cases of hereditary methemoglobinemia. It was normal in the case of the disease without mental retardation, and low with mental retardation. This latter case might be due to the deficiency of cytochrome b5 reductase in the whole tissue.

Blood Platelets↗
PubMed1978

Acceleration of methaemoglobin reduction by riboflavin in human erythrocytes.

The effect of riboflavin on nitrite treated erythrocytes from normal subjects and patients with hereditary methaemoglobinaemia due to the deficiency of NADH-cytochrome b5 reductase was studied in the presence of glucose, 2-deoxy-D-glucose or lactate. When glucose or 2-deoxy-D-glucose was used as a substrate for these erythrocytes, the rate of methaemoglobin reduction in these cells was accelerated more than two-fold in the presence of riboflavin. The acceleration was dependent on the concentration of riboflavin and was suppressed by the addition of atebrin. The stimulative effect of riboflavin was, however, not observed when lactate was used in place of glucose or 2-deoxy-D-glucose. On the basis of these results, the acceleration of methaemoglobin reduction by riboflavin was considered to be due to the activation of NADPH-flavin reductase (Yubisui et al, 1977) in erythrocytes by the reagent. The availability of riboflavin for patients with methaemoglobinaemia due to the deficiency of NADH-cytochrome b5 reductase and for those with toxic methaemoglobinaemia is discussed in relation to methaemoglobin reducing systems in erythrocytes.

Cytochrome-B(5) Reductase↗
PubMedDate not supplied

HIS/RIS contribution to image diagnosis and maximization of efficacy of PACS when coupled with HIS/RIS.

To maximize the efficacy of the PACS coupled with the HIS/RIS and to clarify the effectiveness of the PACS itself, the amount of contribution of the HIS/NS to image diagnosis was measured beforehand. Video-tape recorders were used to record the CRT display of the HIS/RIS terminals and the simultaneous conversation between a patient and his physician in the clinics of our hospital. Consultation time and entry time for image examination order were measured for each case by replay of the tape. Consultation time was approximately 10 min, while order time was 2-3.5 min depending on whether the physician was an internist or an orthopedist. Detailed description on an order was closely related to detailed reports. The HIS/RIS contributed to image diagnosis even before the PACS was coupled. Concrete methods of efficacy maximization of the PACS were pointed out by internists and orthopedists in terms of modalities, outpatient clinics and wards.

Ambulatory Care Facilities↗
PubMedDate not supplied

Five age-dependently expressed genes in mouse brain revealed by the fluorescence differential display-PCR technique.

We used a fluorescence differential display-PCR (FDD-PCR) technique to analyze the genes expressed in mouse brains collected at nine different developmental stages ranging from 3 days to 15 months after birth, and 5 age-dependently expressed genes were found. Age-dependent expression of each of these 5 genes was confirmed by quantitative real-time PCR analysis. Of the 5 genes, 4 (B1-B4) had high homology with the nucleotide sequences of cDNA clones of known mouse genes (myelin proteolipid protein, transferrin, embryo cDNA from the RIKEN full-length enriched library, and protein tyrosine phosphatase), and the rest (B5) with expressed sequence tags of an unknown gene. Sequencing analysis of the full-length cDNA constructed based on the B5 sequence demonstrated that the gene product of B5 was identical to G-substrate, a specific substrate for cGMP-dependent protein kinase. The expression patterns of known genes obtained in our study may provide a further opportunity to investigate the biological and physiological roles of the proteins they encode.

Age Factors↗
PubMedDate not supplied

Expanded selection criterion for Fontan's operation based on the size of distal pulmonary arteries.

This study examined pulmonary arterial size to clarify a quantitative selection criterion for Fontan's operation in six cases without pulmonary hypertension. Pulmonary arterial size was angiographically assessed before and after the operation. No enlargement of the artery was observed, even after the procedure, confirming the importance of preoperative pulmonary arterial size. All three cases with preoperative PAa/N-RPAa of more than 0.5 survived the operation, whereas two of the remaining three cases (less than 0.5) died due to low cardiac output. The only survivor in the latter group had previously received Glenn's anastomosis. Hemodynamic study was done simultaneously, and a significant exponential correlation was obtained between preoperative PAa/N-RPAa and perioperative post-repair right atrial pressure (p less than 0.025). It was concluded that the selection criterion based on pulmonary arterial size could be expanded to a PAa/N-RPAa value of 0.5 when no Glenn's anastomosis had previously been done and the rudimentary right ventricle was not to be utilized. The exponential curve is useful for postoperative care in Fontan's operation, since it indicates the central venous pressure necessary to sustain the circulation at a level corresponding to the preoperative pulmonary arterial size.

Blood Vessel Prosthesis↗