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Y Chida

Publications and source records attributed to Y Chida.

47 records · Page 3Linked to original sources
PubMed1988

Platelet adenine nucleotides in patients with primary glomerular disease.

Total platelet adenosine diphosphate (ADP) and adenosine triphosphate (ATP) contents and amounts of ADP and ATP released from platelets by 3 micrograms/ml of collagen were studied in 20 patients with primary glomerular disease (PGD) to examine the metabolism of these platelet substances in the disease. ADP and ATP were measured by Holmsen's firefly luciferase method. The patients had significantly lower total platelet ATP compared with controls and total platelet ATP was significantly lower in nephrotic patients than in patients whose serum albumin levels were normal. Releasable platelet ADP and ATP were both significantly decreased in patients. Releasable ADP: total ADP ratio and releasable ATP: total ATP ratio were both significantly lower in patients' platelets than in normal platelets. There was no significant difference in platelet counts between patients and controls. Platelet aggregation induced by ADP and adrenaline were significantly higher in patients compared with controls. We conclude that total ATP content and the amount of ADP and ATP released by collagen are decreased in PGD patients' platelets.

Adenosine Diphosphate↗
PubMed1987

Carbostyril derivatives having potent beta-adrenergic agonist properties.

Derivatives carrying a substituent in the para position of the phenyl group of 8-hydroxy-5-[2-[(1-phenyl-2-methylprop-2-yl)amino]-1-hydroxyethyl] carbostyril (10) were prepared and their effects on beta-adrenoceptors evaluated in vitro. Unsubstituted compound 10, iodo 11, amino 12, and bromoacetamido 13 derivatives (all racemic) bound to the receptor with 15-100-fold lower dissociation constants than that of (-)-isoproterenol. All the above compounds stimulated adenylate cyclase more potently than (-)-isoproterenol. The intrinsic activities of compounds 10 and 12 were equal to that of (-)-isoproterenol. The intrinsic activities of compounds 11 and 13 were 1.3 and 1.2 times that of (-)-isoproterenol, respectively. Treatment of membrane preparations with bromoacetamido derivative 13 resulted in an irreversible loss of binding sites, and thus, 13 seems to be an alkylating affinity label for beta-adrenoceptors.

Adenylyl Cyclases↗
PubMed1986

The effect of hemodialysis on lymphocyte subsets during dialysis.

To clarify the effect of hemodialysis on immune response of dialysis patients, peripheral lymphocyte subsets were measured using monoclonal antibodies, OKT3, OKT4, OKT8, OKIal and Leu7. The absolute numbers of OKT3+, OKT4+, OKT8+ and OKIal+ cells were significantly lower in dialysis patients than controls. During dialysis, the relative proportions of OKT3+ and OKT4+ cells increased, and the absolute numbers of OKIal+ and OKT8+ cells decreased, 30 minutes after initiation of dialysis. At the end of the dialysis, the absolute numbers of OKT3+ and OKT4+ cells increased. The absolute number of Leu7+ cells showed low values during dialysis. These changes of lymphocyte subsets during dialysis may have influence on the immune response of dialysis patients.

Adult↗
PubMed1985

Renal survival rate of IgA nephropathy.

In an attempt to identify prognostic indicators in IgA nephropathy, we evaluated the relationship between clinical and histological findings and changes in renal function in 81 patients with IgA nephropathy whose creatinine clearance was more than 80 ml/min at the time of renal biopsy. The incidence of patients whose creatinine clearance decreased to less than 60 ml/min during the follow-up period was calculated with the life table method to designate the renal survival rate. This rate was compared according to the clinical and histological findings at the time of renal biopsy. In conclusion, a statistically significant decrease in the renal survival rate was observed in patients with proteinuria of more than 1.0 g/day, hypertension, severe diffuse proliferative glomerulonephritis, diffuse proliferative glomerulonephritis with focal crescents and glomerular deposition of IgM and/or fibrinogen-related antigen.

Adolescent↗
PubMed1984

Mg2+-dependent unwinding of DNA by nonhistone chromosomal protein HMG(1 + 2) from pig thymus as determined by DNA melting temperature analysis.

In the previous studies with endonucleases specific for single-stranded DNA, we have indicated that the nonhistone chromosomal protein HMG(1 + 2) prepared from pig thymus has an activity to unwind DNA partially at low protein-to-DNA weight ratios (Yoshida, M. & Shimura, K. (1984) J. Biochem. 95, 117-124). In the present work, we have pursued the unwinding reaction by HMG(1 + 2) by thermal melting temperature analysis of DNA, and by investigating the effect of Mg2+ on the reaction. The melting temperature of DNA in the presence of HMG(1 + 2) at low protein weight ratios decreased in 2 mM Tris-HCl, pH 7.8, whereas it increased at higher ratios. The depressions of melting temperature by HMG(1 + 2) at low ratios were not observed either in the system of 2 mM Tris-HCl, pH 7.8, containing EDTA or in the system containing samples treated in advance with EDTA. An addition of Mg2+ to the system reproduced the depression of melting temperature at low protein-to-DNA ratios as well as the increase at higher ratios. Analysis by Mg2+-equilibrated gel filtration revealed that HMG(1 + 2) is a Mg2+-binding protein. However, the depression of melting temperature at low protein-to-DNA ratios was not due to removal of Mg2+ from DNA by HMG(1 + 2). From these results, it is concluded that HMG(1 + 2) causes a partial DNA unwinding detectable by thermal melting temperature analysis of DNA, and that Mg2+ is necessary for the unwinding reaction.

Animals↗
PubMed1984

Unwinding of DNA by nonhistone protein HMG1 and HMG2.

The enzyme kinetic studies with endonucleases specific for single-stranded DNA and the thermal denaturation analyses of DNA showed that a high mobility group (HMG) nonhistone protein fraction HMG (1 + 2), composed of HMG1 and HMG2, has an activity to unwind DNA partially at low protein-to-DNA weight ratio. Isolated HMG1 and HMG2 have the same activity. Divalent cations such as Mg++ or Ca++ were necessary for the unwinding reaction. A peptide containing high glutamic and aspartic (HGA) region, isolated from the tryptic digest of HMG (1 + 2), unwound DNA depending on the presence of Mg++ or Ca++, suggesting that the HMA region in HMG protein is the active site for the DNA unwinding reaction. Poly-L-glutamic acid, employed as a model peptide of the HGA region, showed the activity. Finally, mechanisms of the DNA unwinding reaction by the HMG protein and possible role of the divalent cations are discussed.

Animals↗
PubMed1982

Activation of platelets in patients with chronic proliferative glomerulonephritis and the nephrotic syndrome.

Platelet count, volume and aggregation and plasma levels of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF-4) were measured in 54 patients with chronic glomerulonephritis (CGN). Platelet count and platelet aggregation induced by ADP, adrenaline and collagen were significantly higher in the patients than in normal subjects, and platelet aggregation was markedly increased in the cases with progressive glomerular lesions. Plasma levels of beta-TG and PF-4 were significantly higher in the patients than in the normal subjects. There was a significant inverse correlation between plasma beta-TG and creatinine clearance. Nephrotic patients showed significantly smaller platelet volume and markedly elevated plasma beta-TG levels when compared to the controls. Plasma beta-TG decreased remarkably in 3 out of 4 patients with markedly increased beta-TG levels when they were given antiplatelet drugs. The results suggest that platelet aggregation and the release reaction were increased in patients with CGN. Activated platelets may be an important factor in the genesis of the thrombotic tendency in the nephrotic syndrome.

Adolescent↗
PubMedDate not supplied

Long-term use of low molecular weight heparin ameliorates hyperlipidemia in patients on hemodialysis.

Hyperlipidemia is one of the major risk factors for cardiovascular death in long-term hemodialysis (HD) patients. To clarify whether unfractionated heparin (UFH) contributes to the pathogenesis of hyperlipidemia, nine Type IIb, seven Type IV, and 10 normolipidemic patients, who had been dialyzed with 80.7 IU/Kg heparin, were dialyzed with 40 anti-Xa U/kg of low molecular weight heparin (LMWH) (Logiparin, Novo-Nordisk, Gentfe, Denmark) for 6 months. Seven normolipidemic patients were also dialyzed with heparin as controls. Decreases in triglyceride (TG) during HD with LMWH were significantly less than those with heparin. However, lipoprotein lipase activities (LPL) during HD with LMWH and heparin, and those before and after 6 months on LMWH, were no different. During the 6 months on LMWH, serum total cholesterol, TG, and alpha lipoprotein significantly decreased in Type IIb patients but did not change in Type IV. In contrast, beta lipoprotein slightly increased in Types IIb, IV, and normolipidemic patients who were dialyzed with LMWH but was unchanged in the controls. These observations suggest that UFH aggravates hyperlipidemia in patients, but these effects cannot be attributed to depletion of endothelial LPL liberated by UFH.

Adult↗