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Y Oshima

Publications and source records attributed to Y Oshima.

At least 253 records · Page 14Linked to original sources
PubMed1991

Specific cis-acting sequence for PHO8 expression interacts with PHO4 protein, a positive regulatory factor, in Saccharomyces cerevisiae.

The PHO8 gene of Saccharomyces cerevisiae encodes repressible alkaline phosphatase (rALPase; EC 3.1.3.1). The rALPase activity of the cells is two to three times higher in medium containing a low concentration of Pi than in high-Pi medium due to transcription of PHO8. The Pi signals are conveyed to PHO8 by binding of PHO4 protein, a positive regulatory factor, to a promoter region of PHO8 (PHO8p) under the influence of the PHO regulatory circuit. Deletion analysis of PHO8p DNA revealed two separate regulatory regions required for derepression of rALPase located at nucleotide positions -704 to -661 (distal region) and -548 to -502 (proximal region) and an inhibitory region located at -421 to -289 relative to the translation initiation codon. Gel retardation experiments showed that a beta-galactosidase-PHO4 fusion protein binds to a 132-bp PHO8p fragment bearing the proximal region but not to a 226-bp PHO8 DNA bearing the distal region. The fusion protein also binds to a synthetic oligonucleotide having the same 12-bp nucleotide sequence as the PHO8p DNA from positions -536 to -525. The 132-bp PHO8p fragment, connected at position -281 of the 5' upstream region of a HIS5'-'lacZ fused gene, could sense Pi signals in vivo, but a 20-bp synthetic oligonucleotide having the same sequence from -544 to -525 of the PHO8p DNA could not. Linker insertions in the PHO8p DNA indicated that the 5-bp sequence 5'-CACGT-3' from positions -535 to -531 is essential for binding the beta-galactosidase-PHO4 fusion protein and for derepression of rALPase.

Alkaline Phosphatase↗
PubMed1991

The PHO84 gene of Saccharomyces cerevisiae encodes an inorganic phosphate transporter.

The PHO84 gene specifies Pi-transport in Saccharomyces cerevisiae. A DNA fragment bearing the PHO84 gene was cloned by its ability to complement constitutive synthesis of repressible acid phosphatase of pho84 mutant cells. Its nucleotide sequence predicted a protein of 596 amino acids with a sequence homologous to that of a superfamily of sugar transporters. Hydropathy analysis suggested that the secondary structure of the PHO84 protein consists of two blocks of six transmembrane domains separated by 74 amino acid residues. The cloned PH084 DNA restored the Pi transport activity of pho84 mutant cells. The PHO84 transcription was regulated by Pi like those of the PHO5, PHO8, and PHO81 genes. A PHO84-lacZ fusion gene produced beta-galactosidase activity under the regulation of Pi, and the activity was suggested to be bound to a membrane fraction. Gene disruption of PHO84 was not lethal. By comparison of nucleotide sequences and by tetrad analysis with GAL80 as a standard, the PHO84 locus was mapped at a site beside the TUB3 locus on the left arm of chromosome XIII.

Amino Acid Sequence↗
PubMed1991

AAR1/TUP1 protein, with a structure similar to that of the beta subunit of G proteins, is required for a1-alpha 2 and alpha 2 repression in cell type control of Saccharomyces cerevisiae.

We have cloned a DNA fragment complementing the aar1 mutation defective in the a1-alpha 2 repression of the alpha 1 cistron and haploid-specific genes in Saccharomyces cerevisiae. Nucleotide sequence and mapping data indicated that the AAR1 gene is identical with TUP1, which is allelic to the SFL2, FLK1, CYC9, UMR7, AMM1, and AER2 genes, whose mutations are known to confer a variety of phenotypes, such as thymidine uptake, flocculation, insensitivity to glucose repression, a defect in UV-induced mutagenesis, and a defect in ARS plasmid maintenance. The TUP1/AER2 protein is known to have significant similarity with the beta subunits of G proteins in the C-terminal half, in two glutamine-rich domains in the N-terminal half, and in a central region rich in serine and threonine residues. Disruption of the chromosomal AAR1 gene in alpha and a/alpha cells conferred the nonmating phenotype, and the a/alpha diploids could not sporulate. The AAR1/TUP1 gene is transcribed into a 2.5-kb mRNA independently of the mating-type information of the cell. These observations and mRNA analysis of cell-type-specific genes indicated that the AAR1/TUP1 protein is also indispensable for a1-alpha 2 repression of RME1 and for alpha 2 repression of a-specific genes.

Chromosomes, Fungal↗
PubMed1991

Multiple intracerebral cavernous angioma--case report.

A 65 Year-old man with an episode of absence attacks and mild mental changes was admitted to the clinic. A skull X-ray film demonstrated a mild spotty calcification in the left frontal region. The lesion was recognized as a heterogeneous high density and irregular round egg-sized tumor on computerized tomography and appeared as an avascular mass with cerebral angiography. The patient also had abnormal low-intensity spots that were widely scattered in the supratentorial, parieto-temporal cortex, cerebellum and the pons on MRI (gradient-field echo method). Abdominal echography demonstrated a single tumor shadow in the liver. Only the frontal lesion removed and histological examination confirmed the diagnosis of a cavernous angioma. The scattered low density lesions observed with the MRI (both T1 and T2 weighted) were also indicative of a cavernous angioma. These lesions were probably caused by hemosiderin at different phases of chemical breakdown. The cases of multiple cavernous angiomas reported by McCormick and Rubinstein had a similar appearance with a spot-shaped hemorrhage or angioma. Many other reports of multiple lesions will probably appear in the future with the use of MR, since a small cavernous angioma can be easily visualized by gradient-field echo method.

Aged↗
PubMed1991

Surgical intervention for a giant aneurysm of the vertebral artery--case report.

A radical operation in an elderly man with a giant aneurysm of the vertebral artery was successfully performed. The aneurysm in the posterior fossa caused symptoms such as a disturbance of the lower cranial nerves, as well as pyramidal and cerebellar signs. An aneurysmectomy was performed for decompression of the brain stem and cranial nerves. An extended lateral suboccipital approach was chosen which made it possible to remove the rim of the foramen magnum and reach the condylar fossa. This approach also made access to the vertebro-basilar junction possible for trapping. After resection of the aneurysm and thrombectomy (endaneurysmal microendarterectomy), the aneurysmal neck as well as its clipping was closed, and consequently its parent artery. The procedure is described in this report.

Humans↗
PubMed1991

Bilateral enlargement of the aortic valve ring for valve replacement in children. New operative technique.

We report a new technique for the bilateral enlargement of a small aortic anulus in two children by the insertion of a bifurcated teardrop-shaped Dacron fabric lined with a porcine pericardium. Our experience in two children indicates that this technique will permit the insertion of a prosthetic valve that is four sizes larger than that measured with the native anulus intact in children weighing around 15 kg. It entails no risk of distorting the mitral valve, damaging the conduction system, the main coronary arteries or their important trunks, or of leading to left ventricular dysfunction.

Aortic Valve↗
PubMed1991

[Results of open heart surgery in neonates--comparison between profound hypothermia with circulatory arrest and deep hypothermic bypass].

To investigate factors affecting surgical outcome of open heart surgery in neonates, a retrospective review was carried out on 38 patients operated in the 9 years period from May 1981 to August 1990, in our institution (TAPVR19, TGA7, HLHS7, and others 5). In the former 3 years and 9 month period, 12 patients were operated with the use of profound hypothermia and circulatory arrest (Group I) and in the latest 5 year and 5 month period, continuous deep hypothermic bypass was used in all but for 7 patients with HLHS (Group II). In the group of neonates with TAPVR, operative mortality improved to 7% (1 of 14) in Group II compared to that of 60% (3 of 5) in Group I. CVP and LAP measured immediately after cessation of cardiopulmonary bypass (CPB) were lower in Group II and the value of CPK-MB was significantly lower in Group II. There was a significant negative correlation (r = -0.695, p less than 0.05) between CPB time and urine volume for 72 hours after operation. A significant negative correlation (r = -0.899, p less than 0.01) was also obtained between CPB time and urine volume in the group of 7 neonates with TGA. There was no significant difference in urine volume between patients with TAPVR and TGA despite of significantly longer CPB time in patients with TGA. It is concluded that, 1) improved protection of cardiac and renal function was obtained in neonates operated with the use of continuous deep hypothermic bypass, 2) surgical outcome was influenced by the method of CPB, CPB time and differences in cardiac function ascribed to primary lesions.

Assisted Circulation↗
PubMed1990

Cor triatriatum, coarctation of the aorta, and ventricular septal defect: a rare, surgically correctable anomaly.

A case of cor triatriatum associated with coarctation of the aorta and ventricular septal defect, successfully treated surgically by a staged approach, is reported. This combination is a very uncommon but potentially correctable cause of congestive heart failure and death in infancy. Early accurate diagnosis aided by an awareness of this combination and prompt surgical correction should yield excellent long-term results.

Aortic Coarctation↗
PubMed1990

A toxin profile for shellfish involved in an outbreak of paralytic shellfish poisoning in India.

Toxin profiles of clams and oysters involved in the outbreak of paralytic shellfish poisoning in India in 1983 were studied by a liquid chromatographic technique. Gonyautoxins 1, 2, 3, 4 and 8, and 11-epigonyautoxin 8 appeared to be the major toxins along with small amounts of saxitoxin, neosaxitoxin, decarbamoylsaxitoxin, decarbamoylgonyautoxins 2 and 3, C3 and C4. Toxin profile suggests the involvement of Alexandrium spp. in this outbreak.

Animals↗
PubMed1990

Chromosome engineering in Saccharomyces cerevisiae by using a site-specific recombination system of a yeast plasmid.

We have developed an effective method to delete or invert a chromosomal segment and to create reciprocal recombination between two nonhomologous chromosomes in Saccharomyces cerevisiae, using the site-specific recombination system of pSR1, a circular cryptic DNA plasmid resembling 2 microns DNA of S. cerevisiae but originating from another yeast, Zygosaccharomyces rouxii. A 2.1-kilobase-pair DNA fragment bearing the specific recombination site on the inverted repeats of pSR1 was inserted at target sites on a single or two different chromosomes of S. cerevisiae by using integrative vectors. The cells were then transformed with a plasmid bearing the R gene of pSR1, which encodes the site-specific recombination enzyme and is placed downstream of the GAL1 promoter. When the transformants were cultivated in galactose medium, the recombination enzyme produced by expression of the R gene created the modified chromosome(s) by recombination between two specific recombination sites inserted on the chromosome(s).

Base Sequence↗
PubMed1990

Functional domains of a positive regulatory protein, PHO4, for transcriptional control of the phosphatase regulon in Saccharomyces cerevisiae.

The PHO4 gene encodes a positive regulatory factor involved in regulating transcription of various genes in the phosphatase regulon of Saccharomyces cerevisiae. Besides its own coding region, the 1.8-kilobase PHO4 transcript contains a coding region for a mitochondrial protein which does not appear to be translated. Four functional domains were found in the PHO4 protein, which consists of 312 amino acid (aa) residues as deduced from the open reading frame of PHO4. A gel retardation assay with beta-galactosidase::PHO4 fused protein revealed that the 85-aa C terminus is the domain responsible for binding to the promoter DNA of PHO5, a gene under the control of PHO4. This region has similarities with the amphipathic helix-loop-helix motif of c-myc protein. Determination of the nucleotide sequences of four PHO4c mutant alleles and insertion and deletion analyses of PHO4 DNA indicated that a region from aa 163 to 202 is involved in interaction with a negative regulatory factor PHO80. Complementation of a pho4 null allele with the modified PHO4 DNAs suggested that the N-terminal region (1 to 109 aa), which is rich in acidic aa, is the transcriptional activation domain. The deleterious effects of various PHO4 mutations on the constitutive transcription of PHO5 in PHO4c mutant cells suggested that the region from aa 203 to 227 is involved in oligomerization of the PHO4 protein.

Acid Phosphatase↗
PubMed1990

[Two different spinal tumors (meningioma and schwannoma) with von Recklinghausen's disease in a case].

Von Recklinghausen's neurofibromatosis is a congenital anomaly due to maldevelopment of the neurectoderm and mesoderm. The disease is known to be commonly associated with other tumors of the neural system. We experienced a case in which two different types of spinal tumors (meningioma and schwannoma) appeared together with Von Recklinghausen's disease. The patient was a 54 year-old female. Her chief complaint was slowly progressive lumbar back pain of about a 10-year duration. She was admitted to our hospital after developing such clinical symptoms as paraparesis, bladder and rectal incontinence, and pain in the soles of her feet. The CT study demonstrated a massive tumor at the TH12-L2 levels accompanied with marked scalloping of the posterior vertebral body. The tumor removed was, histologically, meningioma. During surgery, another small bean-size tumor was incidentally found originating from the dorsal root, and it was identified by histological study as typical schwannoma. It has been reported that the incidence rate of spinal tumors in von Recklinghausen's disease is approximately 4%. Although a case has been reported in which different types of tumors developed in both the cranium and the spinal canal, our case as described above is considered extremely rare as far as we can find in reference literature. The pathogenic mechanism of vertebral scalloping as encountered in our case was thought to be based on interactions between hypoplasia of the supporting tissue and pressure generated by the tumor and CSF.

Female↗
PubMed1990

[Mitral valve replacement in 12-month-old infant with parachute mitral valve associated with ventricular and coronary sinus septal defect].

A 12-month-old infant, weighting 6.7 kg, underwent mitral valve replacement with a 17 mm Björk-Shiley prosthetic valve for parachute mitral valve, and patch closure of the associated ventricular and coronary sinus septal defects. Progressive pulmonary artery hypertension and heart failure required surgical intervention. The diagnosis of parachute mitral valve and associated lesions was established by echocardiogram and angiogram. Postoperative recovery was uneventful and he is doing well 3 years after the operation. To our knowledge this is the first successful case to be reported in the literature with such combination of the congenital anomalies.

Age Factors↗
PubMed1990

[Successful correction of truncal valve regurgitation and conduit obstruction after previous Rastelli operation for truncus arteriosus (type I)].

A 9-year-old boy had a successful surgical correction of truncal valve regurgitation and obstruction of extracardiac conduit which ensued previous Rastelli operation. He underwent Rastelli operation at the age of 10 months with the diagnosis of truncus arteriosus (Collet & Edwards Type I). At the age of 8 years, he was admitted because of slow weight gain and cardiomegaly (CTR 64%). Cardiac catheterization showed elevated RV pressure, increased pressure gradient across the conduit and severe truncal valve regurgitation. The extracardiac conduit was replaced with a 22 mm Hancock valved conduit and the truncal valve with 23 mm St. Jude Medical aortic valve. Postoperative catheterization revealed a normal RV pressure, only slight pressure gradient across the conduit and no truncal valve regurgitation. He is doing quite well 2 years after the operation.

Blood Vessel Prosthesis↗
PubMed1990

[Cor triatriatum associated with coarctation of the aorta and VSD].

A case of cor triatriatum associated with coarctation of the aorta (CoA) and VSD is reported. A 4-month-old boy underwent subclavian flap aortoplasty and ligation of PDA with the diagnosis of CoA and VSD. At the age of 1 year and 2 months, echocardiography revealed an abnormal subdividing membrane in the left atrium. Under the definite diagnosis of cor triatriatum (Lucas & Schmidt type I B1) and VSD, complete removal of the abnormal septum, patch closure of ASD and VSD was performed with the aid of cardiopulmonary bypass, blood cardioplegia and topical cardiac cooling. Postoperative course was uneventful and the patient was discharged from the hospital on the 38th postoperative day. An association of cor triatriatum, VSD, and coarctation of the aorta is very rare, and to our knowledge, the case presented here seems to be the first report of successful total correction by a staged approach in the literature.

Aortic Coarctation↗
PubMed1990

[Partial closure of the atrial septal primum defect and biventricular repair for a case of hypoplastic right ventricle with partial atrioventricular canal defect].

An eight-year-old girl with partial atrioventricular canal defect and hypoplastic right ventricle was treated successfully by a palliative open-heart surgery. The preoperative right ventricular pressure was 58/7 mmHg (RVP/LVP = 0.67) and morphology of the right ventricle showed severe tricuspid stenosis and small outflow portion. The preoperative RVEDVI was 31 (41% of normal and tricuspid annulus was 17 mm (47% of normal). The right ventricular outflow was reconstructed with insertion of MVOP and the ASD was partially left open (the amplitude of the interatrial communication was 7 mm). Angiocardiogram two and half years after the operation demonstrated significant right ventricular growth with no right to left shunt through interatrial communication. The RVEDVI was 46 (56% of normal) and tricuspid annulus was 36 mm (90% of normal). This technique can be a procedure of choice in patient with right ventricular hypoplasia, who is not candidate for simple right ventricular reconstruction nor Fontan procedure, as the growth of the right ventricule is expected in the future.

Child↗
PubMed1990

[Staged operation for supravalvular aortic stenosis syndrome associated with severe multiple peripheral pulmonary stenoses: a case report and surgical methods].

Successful surgical correction of supravalvular aortic stenosis (SAS) syndrome associated with severe peripheral pulmonary stenosis by a staged approach in a 6-year-old boy is reported. Right ventriculogram demonstrated bilateral severe peripheral pulmonary stenoses and cardiac catheterization revealed severe pressure gradient of 94 mmHg between the trunk of pulmonary artery and right and left peripheral pulmonary arteries, respectively. Bilateral severe peripheral pulmonary stenoses were relieved successfully by staged operations. Initially, a stenotic portion of the right pulmonary artery and its bifurcation was removed and a DeBakey Knitted Dacron graft was interposed between the right pulmonary artery and the peripheral pulmonary artery which was enlarged by arterioplasty. Nine days later, stenosis of the left peripheral pulmonary artery was relieved by arterioplasty using a Rygg patch. Finally, 8 months after the initial operation, the patient underwent definitive repair of SAS by extended aortoplasty. The postoperative course of the patient was uneventful. Our experience indicates that in the surgical treatment of the patient with SAS and associated severe multiple peripheral pulmonary stenoses, a staged approach, that is initial staged repair of the bilateral pulmonary stenoses by arterioplasty through thoracotomy followed by definitive intracardiac repair of SAS, is the procedure of choice.

Aortic Valve Stenosis↗