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N Hayashida

Publications and source records attributed to N Hayashida.

At least 73 records · Page 4Linked to original sources
PubMed1997

Rapid construction of a transcription map for a cosmid contig of Arabidopsis thaliana genome using a novel cDNA selection method.

Significant progress has been made on the random sequencing of cDNAs (ESTs) and the genetic and physical mapping of the Arabidopsis thaliana genome. New techniques are now required to identify and map the expressed genes efficiently on A. thaliana chromosomes. A novel method to construct a transcription map of expressed genes or cDNAs in specific regions of the genome using DNA-latex particles has been developed. The region-specific DNA fragments prepared from six cosmid clones that constitute a contig covering the abi1 locus on chromosome 4 were covalently bound to latex particles. The DNA-latex particles were used for the selection of region-specific cDNAs. Sequence analysis of the cDNA clones revealed that ABI1, RPS2, casein kinase 1 (CK1), nucleosome assembly protein I (NAP) cDNAs and T20837 EST, which are situated within the contig near abi1 locus, were selected. These results indicate that the cDNAs in the specific region of the genome were faithfully selected with this method. Sequence analysis also indicated that 11 selected cDNAs were derived from novel genes located near the abi1 locus and that four of the selected cDNAs encode putative proteins that have sequence similarity to cationic peroxidase, phosphatidylserine decarboxylase 2 (PSD2), trans-caffeoyl CoA 3-O-methyltransferase (CCoAMT), and proteasome subunit XC3.

Arabidopsis↗
PubMed1997

Hemodynamic performance of the St. Jude Medical Hemodynamic Plus valve.

The hemodynamic performance of the St. Jude Medical Hemodynamic Plus valve (HP) for a small aortic annulus was compared to that of the standard St. Jude Medical valve (SJM). Doppler echocardiographic parameters were evaluated in patients undergoing aortic valve replacement with either a 19 mm HP (HP19, n = 7), a 21 mm HP (HP21, n = 8), a 19 mm SJM (SJM19, n = 16), or a 21 mm SJM (SJM21, n = 34). The peak and mean pressure gradients and peak flow velocity were significantly (p < 0.05) lower in both patients with the HP21 and those with the HP19 than patients with the SJM21 and those with the SJM19, respectively. The echocardiographic parameters of the patients with the HP19 corresponded closely to those of patients with the SJM21. The left ventricular mass index regressed markedly in patients with the HP19 during the late postoperative period. The results suggested that the hemodynamic performances of certain sizes of the HP were superior to those of the same size SJMs and were considered to be equivalent to those of the next size larger SJM.

Adolescent↗
PubMed1997

[A case of modified Fontan operation for corrected transposition of great arteries (I.D.D.) with atrial septal defect, ventricular septal defect, pulmonary stenosis, mitral atresia and hypoplastic left ventricle].

A 14-year-old boy with corrected transposition of the great arteries (I.D.D.), atrial septal defect, ventricular septal defect, pulmonary stenosis, mitral atresia and hypoplastic left ventricle was successfully operated. He had undergone modified Blalock-Taussig shunt at the age of two. After atrial septal defect was closed with bovine pericardial patch, small ventricular septal defects were closed directly through left ventricular incision. Then the incisional line on the left ventricle was extended to pulmonary artery. The stenotic and thickened pulmonary valve was excised. The upper part of the incisional line on the right atrium and that on the left ventricle were anastomosed. Consequently the connection between the right atrium and the pulmonary artery was able to be made through hypoplastic left ventricle. This case is extremely rare type in terms of mitral atresia and is classified as Group II, type B according to Eliot's classification. This type of repair is similar to Björk's method, however, we could not make use of left ventricular contraction because it was weak. The merit of this procedure was to be able to reconstruct blood tract without using artificial conduits.

Adolescent↗
PubMed1996

A gene encoding a mitogen-activated protein kinase kinase kinase is induced simultaneously with genes for a mitogen-activated protein kinase and an S6 ribosomal protein kinase by touch, cold, and water stress in Arabidopsis thaliana.

We describe here the cloning and characterization of a cDNA encoding a protein kinase that has high sequence homology to members of the mitogen-activated protein kinase (MAPK) kinase kinase (MAPKKK or MEKK) family; this cDNA is named cATMEKKI (Arabidopsis thaliana MAP kinase or ERK kinase kinase 1). The catalytic domain of the putative ATMEKK1 protein shows approximately 40% identity with the amino acid sequences of the catalytic domains of MAPKKKs (such as Byr2 from Schizosaccharomyces pombe, Ste11 from Saccharomyces cerevisiae, Bck1 from S. cerevisiae, MEKK from mouse, and NPK1 from tobacco). In yeast cells that overexpress ATMEKK1, the protein kinase replaces Ste11 in responding to mating pheromone. In this study, the expression of three protein kinases was examined by Northern blot analyses: ATMEKK1 (structurally related to MAPKKK), ATMPK3 (structurally related to MAPK), and ATPK19 (structurally related to ribosomal S6 kinase). The mRNA levels of these three protein kinases increased markedly and simultaneously in response to touch, cold, and salinity stress. These results suggest that MAP kinase cascades, which are thought to respond to a variety of extracellular signals, are regulated not only at the posttranslational level but also at the transcriptional level in plants and that MAP kinase cascades in plants may function in transducing signals in the presence of environmental stress.

Amino Acid Sequence↗
PubMed1996

Selective Isolation of DNA or RNA Using Single-Stranded DNA Affinity Latex Particles.

We developed latex particles with a diameter of about 0.22 µm on which single-stranded (ss) DNA was covalently coupled to select or enrich its complementary DNA or mRNA. DNA was first covalently coupled to the latex particles in the double-stranded (ds) form with both blunt and protruding ends. More than 80% of the dsDNA was coupled through the ssDNA stretch at its protruding end. The presence of NaCl in the immobilization reaction severely inhibited DNA from coupling to the particles. The particles were then treated with alkali or heated to denature the dsDNA and sedimented by a brief centrifugation to yield ssDNA immobilized particles. They allowed the selective and efficient isolation of a desired RNA from total cellular RNA.

Journal Article↗
PubMed1996

Effect of the addition of albumin to crystalloid cardioplegic solutions on myocardial metabolism in infants undergoing open heart surgery.

The effect of the addition of albumin to crystalloid cardioplegic solutions was investigated in infants who underwent open heart surgery. The patients were divided into four groups according to whether or not they received a composition of crystalloid cardioplegic solutions containing albumin. Cardioplegic solution (Kurume solution) without albumin was administered to 12 patients (group 1); Kurume solution with 1% albumin to 10 patients (group 2); GIK solution without albumin to 10 patients (group 3); and GIK solution with 1% albumin to 15 patients (group 4). All patients had a ventricular septal defect and underwent closure of the defect with Dacron double velours through either the tricuspid or pulmonary valve. Our results showed that the percent oxygen extraction in group 2 was significantly greater than that in group 1, while the value in group 4 was less than that in group 3 at 5 min after reperfusion. No significant differences were seen between groups 1 and 2, or between groups 3 and 4, regarding the value for creatine kinase muscle-brain (MB) for any measurements during reperfusion. However, regarding the percent lactate and the malondialdehyde extraction values, significant differences between the groups with and without albumin were noted 5 min after reperfusion. These results did not completely support the addition of albumin to crystalloid cardioplegic solutions to help preserve myocardial aerobic metabolism in infants; however, such an addition might contribute to the preservation of myocardial lactate utilization while also helping to inhibit lipoperoxide metabolism immediately after reperfusion.

Cardioplegic Solutions↗
PubMed1996

Intermediate clinical results of combined gastroepiploic and internal thoracic artery bypass.

BACKGROUND: To improve the postoperative results of coronary artery bypass grafting (CABG), the internal thoracic artery (ITA) has become the conduit of choice, with a low operative risk. The gastroepiploic artery as a third arterial conduit for grafting was first reported in 1987, and the early results were reported to be as good as those for the ITA graft. In this report, we present the intermediate-term results of combining ITA and gastroepiploic artery grafts up to 7 years after the operation. METHODS: Between April 1988 and April 1992, 214 patients received CABG with at least one ITA graft and were followed up for more than 3 years. They were divided into two groups: Group I consisted of 155 patients who had CABG using one ITA with or without saphenous vein grafts, and group II consisted of 59 patients who had CABG using an ITA and a gastroepiploic artery with or without saphenous vein grafts. The duration of follow-up for hospital survivors ranged from 36 to 89 months. RESULTS: There were six late cardiac deaths in group I and one in group II. Fifteen patients complained of recurrent symptoms of angina: 13 in group I and 2 in group II. The actuarial survival rate excluding noncardiac deaths was 95.9% in group I and 96.8% in group II at 7 years (p = not significant). The cardiac event-free rate was 75.4% in group I and 92.2% in group II, which was a significant difference (p < 0.05). CONCLUSIONS: When using both the ITA and gastroepiploic artery, CABG can be performed with minimal operative risk and seems to offer an improved quality of life at least 7 years postoperatively.

Adolescent↗
PubMed1996

Antegrade and retrograde cardioplegia: alternate or simultaneous?

UNLABELLED: Neither antegrade nor retrograde cardioplegic protection provides homogeneous distribution, and a combination may be required to avoid anaerobic metabolism and depressed postoperative ventricular function. Tepid cardioplegia (29 degrees C) avoids the delayed recovery of cardiac function and metabolism associated with cold cardioplegia (15 degrees C) and reduces the anaerobic metabolism seen with warm (37 degrees C) cardioplegia. We compared two techniques that combine antegrade and retrograde tepid cardioplegia: alternate and simultaneous. METHODS: Sixty patients undergoing elective isolated coronary artery bypass grafting were randomized to receive near continuous tepid retrograde and either intermittent antegrade cardioplegia (the alternate technique) or antegrade cardioplegia with the solution delivered concurrently through each completed vein graft (the simultaneous technique). RESULTS: Myocardial lactate extraction was greater after crossclamp release following simultaneous than alternate cardioplegia. Postoperative ventricular function was better after alternate than simultaneous cardioplegia. CONCLUSION: Both techniques permitted rapid postoperative recovery of myocardial metabolism and ventricular function. However, simultaneous cardioplegia was simpler and did not require deairing the aortic root between antegrade infusions.

Adult↗
PubMed1996

[Surgery for aortic valvular disease with congenital quadricuspid aortic valve].

A case of quadricuspid aortic valve is reported. A 69-year-old man was hospitalized with chest oppression at rest and abnormal electrocardiogram and diagnosed aortic regurgitation by echocardiography and aortic angiography. Aortic regurgitation was grade III according to Seller. Aortic valve replacement was performed successfully with a 21 mm St. Jude Medical valve. The aortic valve showed four cusps consisting of two equal larger cusps and two equal smaller cusps which was type C according to Hurwitz. Each valve was thickened and adhered, and fenestrations were found at each commissure. The right coronary ostium was small but not displaced. Twenty five cases in literature which were corrected surgically are also reviewed. Quadricuspid aortic valve is a rare anomaly but must be considered as a malformation which leads to severe valve failure in later life.

Aged↗
PubMed1995

Construction of a cDNA library for a specific region of a chromosome using a novel cDNA selection method utilizing latex particles.

A novel method is described for the rapid concentration of particular cDNAs and their mapping to specific regions of a genome. The strategy for 'cDNA scanning' is based on the hybridization of an entire library of cDNAs to a large fragment of genomic DNA that is covalently bound to latex particles. The hybridized cDNAs are eluted, amplified by PCR and cloned into a lambda vector. Selected cDNAs that hybridized to the genomic DNA are cloned, with subsequent sequence analysis. Region-specific DNA fragments prepared from a yeast artificial chromosome (YAC) clone, EG10D9, which maps to chromosome 5 of the small cruciferous plant Arabidopsis thaliana (At), were used to prepare a model system and were covalently bound to latex particles. cDNAs that hybridized to EG10D9 were concentrated by hybridization to the immobilized DNA. The hybridized cDNAs were recovered and amplified by PCR. The resultant sub-library of cDNAs of 0.5-2 kb in length was enriched about 1000-fold. The partial sequences of the cDNAs provided information about genes that are located on the EG10D9 region of the At genome. The cDNA scanning strategy provides an efficient method for the mapping of expressed genes which could be used as expressed sequence tags (EST) within a genome.

Arabidopsis↗
PubMed1995

Two genes that encode ribosomal-protein S6 kinase homologs are induced by cold or salinity stress in Arabidopsis thaliana.

We have isolated two closely related cDNA clones (cATPK19 and cATPK6) with homology to protein-serine/threonine kinases from Arabidopsis thaliana using the polymerase chain reaction (PCR). The deduced amino acid sequences of the ATPK19 and ATPK6 contain all 11 conserved regions of the catalytic domain of protein kinases, and have homology to p70 ribosomal S6 kinases (52%). ATPK19 and ATPK6 have putative PEST regions in their N- and C-terminal regions, and these regions also contain putative phosphorylation sites that are recognized by casein kinases or proline-directed protein kinases such as cdc2, MAP kinase, and p54 MAP-2 kinase (SAPK). The transcription levels of the ATPK19 and ATPK6 genes rapidly and markedly increased when plants were subjected to cold or high-salt stresses. These observations suggest that ATPK19 and ATPK6 may function in the adaptation of plant cells to cold or high-salt conditions, providing an understanding of the role of protein phosphorylation in plant responses to environmental stresses.

Adaptation, Physiological↗
PubMed1995

Differential effect of the retropleural and retroperitoneal environments on healing of the inner wall of porous fabric prostheses in the thoracic and abdominal aorta of the same dog.

Healing of the inner wall of the same preclotted knitted Dacron arterial prostheses was compared in the descending thoracic aorta (DTA) and the abdominal aorta (AA) of the same dog. Each of 16 dogs received this dual implantation with study periods of 4 weeks for five dogs, 8 weeks for five dogs, and 16 weeks for six dogs. Healing was studied with light microscopy, scanning electron microscopy, transmission electron microscopy, and immunocytochemistry identification. The outer capsule was firmly adherent to the Dacron framework of all grafts implanted in the DTA; advanced healing of the inner wall of all thoracic grafts was present by 4 weeks, nearly complete healing by 8 weeks, and complete healing by 16 weeks. In contrast, the outer capsule was either not attached or only loosely adherent to the Dacron framework in eight AA grafts (50%), and in these implants no healing of the inner wall occurred beyond the limited perianastomotic pannus zone. In the other eight implants in which the outer capsule was firmly adherent to the Dacron framework, healing was roughly comparable to that in the grafts implanted in the DTA. This study demonstrated that (1) DTA grafts heal faster and more completely than AA grafts, (2) healing and endothelialization are related to the tightness of the outer capsule, (3) there is a high incidence of loose tissue attachment in the AA, and (4) healing of aortic grafts is site specific.

Animals↗
PubMed1995

Tepid antegrade and retrograde cardioplegia.

To determine the optimal temperature for the combination of antegrade and retrograde cardioplegia, 42 patients undergoing coronary artery bypass grafting were randomized to receive cold (9 degrees C; n = 14), tepid (29 degrees C; n = 14), or warm (37 degrees C; n = 14) blood cardioplegia delivered continuously retrograde and intermittently antegrade. Myocardial oxygen utilization, lactate and acid metabolism, and coronary vascular resistance were measured during the operation and cardiac function was assessed postoperatively. Myocardial oxygen consumption, lactate release and acid release were greatest with warm, intermediate with tepid, and least with cold cardioplegia (p = 0.0001). However, washout of lactate and acid at the time of cross-clamp release was reduced (p = 0.022) with tepid or cold compared with warm cardioplegia. Early postoperative left ventricular function was best preserved (p = 0.01) after tepid than after cold or warm combination cardioplegia. These results suggest that tepid combination cardioplegia reduced metabolic demands but permitted immediate recovery of cardiac function. This technique may provide better myocardial protection than cold or warm combination cardioplegia.

Aged↗