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Y Ohtake

Publications and source records attributed to Y Ohtake.

At least 73 records · Page 4Linked to original sources
PubMed1995

KRB1, a suppressor of mak7-1 (a mutant RPL4A), is RPL4B, a second ribosomal protein L4 gene, on a fragment of Saccharomyces chromosome XII.

The mak7-1 mutant loses the killer toxin-encoding M1 dsRNA. MAK7 is RPL4A, one of two genes encoding ribosomal protein L4. KRB1 is a dominant suppressor of mak7-1 that is tightly centromerelinked, but not linked to centromere markers of chromosomes I-XVI. Our orthogonal field agarose gel electrophoresis analysis of chromosomal DNA from strains with KRB1 shows a novel band of approximately 250 kb. This band hybridizes with an RPL4B-specific probe, but not an RPL4A (MAK7)-specific probe. The RPL4B-specific probe also hybridizes to chromosome XII where the original RPL4B is located. KRB1 is meiotically linked to this extra chromosome. Disruption of either the RPL4B gene on chromosome XII or that on the extra chromosome results in loss of the killer phenotype and a decreased concentration of free 60S subunits. Thus, the RPL4B on the extra chromosome is KRB1 and is active. The extra chromosome contains chromosome XII sequence between Lambda 5345 clone (ATCC70558) and Lambda 6639 clone (ATCC71085) of Olson's Lambda library, indicating that KRB1 represents a chromosomal rearrangement involving chromosome XII and explaining the earlier genetic data.

Base Sequence↗
PubMed1995

Yeast virus propagation depends critically on free 60S ribosomal subunit concentration.

Over 30 MAK (maintenance of killer) genes are necessary for propagation of the killer toxin-encoding M1 satellite double-stranded RNA of the L-A virus. Sequence analysis revealed that MAK7 is RPL4A, one of the two genes encoding ribosomal protein L4 of the 60S subunit. We further found that mutants with mutations in 18 MAK genes (including mak1 [top1], mak7 [rpl4A], mak8 [rpl3], mak11, and mak16) had decreased free 60S subunits. Mutants with another three mak mutations had half-mer polysomes, indicative of poor association of 60S and 40S subunits. The rest of the mak mutants, including the mak3 (N-acetyltransferase) mutant, showed a normal profile. The free 60S subunits, L-A copy number, and the amount of L-A coat protein in the mak1, mak7, mak11, and mak16 mutants were raised to the normal level by the respective normal single-copy gene. Our data suggest that most mak mutations affect M1 propagation by their effects on the supply of proteins from the L-A virus and that the translation of the non-poly(A) L-A mRNA depends critically on the amount of free 60S ribosomal subunits, probably because 60S association with the 40S subunit waiting at the initiator AUG is facilitated by the 3' poly(A).

Genes, Fungal↗
PubMed1995

[The effect of fixed night work on blood pressure of male bakery workers in a processing plant].

The effect of fixed night work on blood pressure was investigated for the 13 male bakery workers. All were on the fixed night duty for the first 5 years. The mean BP values of the subjects began to rise significantly from the 4th year. At the 6th year, half of the subjects switched to working in shifts. After that, no increase in the mean BP values was seen in this group. Further increase in the values was observed in the other group on the night duty. However, a two-hour nap late at night prevented the rise of the mean BP values.

Adult↗
PubMed1994

Absolute glutathione requirement for sporulation of a yeast Saccharomyces cerevisiae.

The glutathione (GSH)-deficient yeast cells of Saccharomyces cerevisiae completely failed to sporulate in nutrition-deprived medium containing potassium acetate (SPO medium). The sporulation defect of the yeast was restored only when the yeast cells were incubated in SPO medium in the presence of GSH or its derivative such as oxidized GSH and gamma-L-glutamyl-L-cysteine. It was concluded that GSH was indispensably required to enter into meiosis and/or sporulation processes of the yeast Saccharomyces cerevisiae.

Acetates↗
PubMed1993

Reduction of immunoreactivity of bovine serum albumin conjugated with comb-shaped polyethylene glycol derivatives.

Bovine serum albumin (BSA) was chemically modified with two types of comb-shaped copolymers of polyethylene glycol derivative and maleic anhydride, one with the molecular weight of 13,000 (activated PM13) and the other with 100,000 (activated PM100), to form PM13- and PM100-BSA. The immunoreactivity of BSA was markedly reduced by coupling with each modifier and was completely lost when 30% or 20% of amino groups in BSA were modified with activated PM13 or PM100, respectively. The esterase activity of PM13- and PM100-BSA without immunoreactivity were retained 63% and 93% of non-modified one, respectively. These results were discussed with those of modified-asparaginases(1).

Asparaginase↗
PubMed1993

[Combined resection of the aortic wall in T4 lung cancer under the assistant devices].

Radical operation for T4 lung cancer is technically difficult. We report here 3 cases of T4N0M0 lung cancer involving aorta or left subclavian artery which was successfully operated on. We could carry out combined aortic resection more safely and speedy under the assistant devices, such as Anthrontube and Biomedicus Centrifugal Pump. Even T4 lung cancer having aortic invasion with N0 disease can be operated on and be expected long-term survival using these assistant devices.

Adenocarcinoma↗
PubMed1992

[Combined resection of the aorta in a T4 lung cancer under nonheparinized temporary bypass using Anthron tube].

A 63-year-old male had squamous cell carcinoma in the left upper lobe. CT scan suggested the invasion of the tumor into the vertebral body and the descending aorta. Left pneumonectomy and combined aortic resection under the temporary bypass using Anthron tube was performed. The bypass using Anthron tube provides us no systemic heparinization and the procedure is easy. So the danger of massive bleeding during and after the operation can be decreased and the operative time can also be shortened. This procedure may be a great help for carrying out the operation with combined aortic resection more safely and speedily.

Aorta↗
PubMed1991

Molecular cloning of the gamma-glutamylcysteine synthetase gene of Saccharomyces cerevisiae.

The 4.4 kb SphI DNA fragment (GSH1) that complements the gamma-glutamylcysteine synthetase-deficient mutation (gsh1) of Saccharomyces cerevisiae YH1 was cloned into vector plasmid YEp24. Gene disruption of the cloned fragment confirmed that this segment was the same gene as gsh1. Mutant strain YH1 with this plasmid not only restored gamma-glutamylcysteine synthetase (GSH-I) activity but the glutathione content and the growth rate. DNA sequence analysis of the SphI fragment showed that the GSH1 structural gene contained 2034 bp and predicted a polypeptide of 678 amino acids. The deduced amino acid sequence had about a 45% homology to that of rat kidney GSH-I, but a very low homology (about 26%) to that of Escherichia coli GSH-I. Northern analysis showed that GSH1 had been transcribed into an approximately 2.7 kb mRNA fragment. Southern analysis showed that GSH1 mapped at chromosome X.

Amino Acid Sequence↗
PubMed1991

Ventricular assistance by right free wall dynamic cardiomyoplasty following acute right heart failure in canines.

The efficacy of right ventricular assistance provided by electrically conditioned skeletal muscle was studied in 17 canines. The right ventricular free wall was made ischemic and akinetic by ligating all coronary branches supplying it. The latter procedure led to deterioration of hemodynamic parameters. After that, 14 canines were divided into two groups: group 1 (n = 8) was observed without cardiomyoplasty for 2 hours; group 2 (n = 6) underwent right ventricular dynamic cardiomyoplasty with the conditioned left latissimus dorsi. The deterioration in hemodynamic parameters in group 1 showed no further significant change during the period of observation. In group 2, right ventricular function was augmented by cardiomyoplasty, as shown by a significant increase in right ventricular and pulmonary artery pressures. In addition, decreased CVP suggested improved right ventricle (RV) filling. Right ventricular function curves obtained by volume loading in a further group of three canines, group 3, also demonstrated improved right ventricular function. Thus right ventricular dynamic cardiomyoplasty appears to contribute significantly to right ventricular function in a model of acute right heart failure.

Acute Disease↗
PubMed1991

Interrelationship between hepatic ureagenesis and gluconeogenesis in early sepsis.

This study was performed to investigate the interrelationship between gluconeogenesis and ureagenesis during sepsis. In isolated perfused livers, gluconeogenesis was assessed using either lactate or a combination of lactate, glutamine, and alanine as substrate. Ureagenesis was assessed using either NH4Cl or glutamine plus alanine as substrate. NH4Cl stimulated urea production in livers from both septic and sham-operated control rats. Urea release was approximately 1.2 and 2.0 mg urea nitrogen.g-1.h-1 for 1 and 5 mM NH4Cl, respectively, and was equal for both groups. With amino acids as substrate, urea production was significantly greater in livers from septic animals compared with controls. Phenylephrine stimulated urea production in the sham-operated group by about twofold, whereas in the septic group urea release was slightly inhibited. Gluconeogenesis from lactate was inhibited by NH4Cl (1 and 5 mM) in both groups, with no difference between groups. In contrast to enhanced ureagenesis from amino acids in septic rats, gluconeogenesis was decreased by approximately 24% (P less than 0.5). Similarly, phenylephrine (1 microM) stimulated gluconeogenesis by 13 +/- 1 mumol.g-1.h-1 in sham-operated rats but only by 9 +/- 1 mumol.g-1.h-1 in septic rats (P less than 0.02). These results suggest that hepatic gluconeogenic and ureagenic pathways are intact in sepsis but that altered substrate preference and hormone sensitivity may result in decreased gluconeogenesis in the presence of elevated amino acid levels.

Alanine↗
PubMed1991

[Hemopurification in the management of ARDS complicating multiple organ failure].

In the field of critical care medicine, it has been claimed that ARDS often develops as a part of multiple organ failure (MOF). Since multi-modality therapy is necessary in the management of MOF, it is also mandatory even in the management of ARDS. Among the various therapeutic approaches for patients with MOF, hemopurification is one of the most effective therapeutic tools. Various hemopurification methods such as hemodialysis, peritoneal dialysis, hemoadsorption, hemofiltration and plasma exchange have been applied in the management of MOR. However, our recent experiences suggest that continuous hemofiltration (CHF) and/or continuous hemodiafiltration (CHDF) are safest, most easily performed and effective hemopurification in the management of ARDS/MOF. The efficacy of hemopurification in the management of ARDS is summarized as follows. 1) Removal of humoral mediators and causative substances of ARDS following insults such as sepsis and trauma. 2) Treatment of pulmonary interstitial permeability edema which has been claimed to be one of the most important pathological conditions in ARDS. 3) Removal of excess water given as carrier in IVH solution and accumulating in the body. 4) Immunomodulation which has also been considered to be necessary in the treatment or prevention of ARDS.

Hemofiltration↗
PubMed1990

Rapid conversion of the new angiotensin converting enzyme inhibitor ramipril to its active metabolite in rats.

The rate of conversion of ramipril (Hoe 498), a new angiotensin converting enzyme (ACE) inhibitor, to its active metabolite was compared with that of enalapril. After intravenous administration to rats, ramipril was very rapidly deesterified to its active moiety, ramiprilat. The ratio of the active metabolite level to the prodrug level in plasma at 5 min after administration was 10.7 for ramipril, which was about 5 times the ratio for enalapril. The in vitro conversion rates of ramipril were higher than those of enalapril in all rat tissue homogenates examined, including the liver, a main site of metabolism. The apparent Km values of ramipril and enalapril in the liver were 190 and 710 mumol/l, respectively, suggesting that ramipril has a higher affinity for esterase than enalapril. In conclusion, ramipril was superior to enalapril in efficiency of conversion to the active metabolite.

Angiotensin-Converting Enzyme Inhibitors↗