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M Ohta

Publications and source records attributed to M Ohta.

At least 397 records · Page 22Linked to original sources
PubMed1996

Src-homology domain 2 is responsible for transcriptional suppression induced by expression of Lck.

Overexpression of Lck was shown, by our previous study, to suppress gene transcription from various viral and cellular promoters. The suppression of transcription from human T-cell leukemia virus promoter by Lck was independent of the presence of the enhancer core sequences within the long terminal repeat. The suppression of transcription was observed with Lck mutants that had either diminished or enhanced tyrosine-kinase activity. A mutant lacking the myristylation site also suppressed transcription. From the analysis with various deletion mutants of Lck, it was suggested that Src-homology domain 2 (SH2) is both necessary and sufficient for the suppression of transcription. A similar effect was also observed with the SH2 domain of the v-src gene. Thus, overexpression of Lck could suppress gene expression through a unique function of the SH2 domain.

Amino Acid Sequence↗
PubMed1996

Structure of the human receptor tyrosine phosphatase gamma gene (PTPRG) and relation to the familial RCC t(3;8) chromosome translocation.

The receptor protein tyrosine phosphatase gamma gene, PTP gamma (locus name PTPRG), was previously mapped to chromosome region 3p14.2, within a 2- to 4-Mb region centromeric to the 3p14.2 breakpoint of the t(3;8) familial renal cell carcinoma (RCC)-associated constitutional chromosome translocation. Because of its chromosomal position, its enzymatic properties as a receptor phosphatase, which might oppose a growth activating kinase activity, its homozygous deletion in murine L cells, and its transcriptional activity in numerous normal tissues, including kidney, the PTP gamma gene was an attractive tumor suppressor gene candidate for renal cell carcinoma. To determine whether the PTP gamma gene was a target of loss of heterozygosity or mutation in RCCs and to determine its map position relative to the t(3;8) break at 3p14.2, we have isolated YAC and lambda genomic clones for the PTP gamma gene and other 3p14.2 markers and determined the relative positions of the t(3;8) break, a 3p14.2 de novo break possibly in a fragile site, and the 5' end of the PTP gamma gene. Additionally, the genomic structure, position of the proximal promotor, and intron-exon border sequences of the 30-exon 780-kb PTP gamma gene have been determined, which will facilitate analysis of the PTP gamma gene in tumors.

Base Sequence↗
PubMed1996

Potential gastrointestinal tumor suppressor locus at the 3p14.2 FRA3B site identified by homozygous deletions in tumor cell lines.

A number of DNA fragments, identified by representational difference analysis, which were homozygously deleted in various cancer cell lines were previously mapped to human chromosomal arms. One of these, BE758-6, which was homozygously deleted in a number of colon carcinoma cell lines, had been mapped to chromosome region 3p. We have further localized the probe to 3p14.2, approximately 350kbp telomeric to the 3p14.2 break of the t(3;8) hereditary renal cell carcinoma chromosome translocation, within or near the 3p14.2 FRA3B, the most common human fragile site. We determined the sizes of the homozygous deletions in a number of cancer cell lines after isolation of a yeast artificial chromosome contig and development of STS markers which fall between D3S1234 and D2S1481, which flank the deletions. Homozygous deletions were observed and sized not only in the cell lines originally reported but also in a number of nasopharyngeal carcinoma cell lines and a gastric carcinoma cell line. About 50% of uncultured stomach and colon carcinomas were then shown to lose heterozygosity for alleles in the same region, with a common region of loss between the D3S1234 and D3S1481 markers. Thus, it is likely that the homozygous deletion observed in these cancer cell lines harbors an important tumor suppressor gene for several tumor types.

Base Sequence↗
PubMed1996

The FHIT gene, spanning the chromosome 3p14.2 fragile site and renal carcinoma-associated t(3;8) breakpoint, is abnormal in digestive tract cancers.

A 200-300 kb region of chromosome 3p14.2, including the fragile site locus FRA3B, is homozygously deleted in multiple tumor-derived cell lines. Exon amplification from cosmids covering this deleted region allowed identification of the human FHIT gene, a member of ther histidine triad gene family, which encodes a protein with 69% similarity to an S. pombe enzyme, diadenosine 5', 5''' P1, P4-tetraphosphate asymmetrical hydrolase. The FHIT locus is composed of ten exons distributed over at least 500 kb, with three 5' untranslated exons centromeric to the renal carcinoma-associated 3p14.2 breakpoint, the remaining exons telomeric to this translocation breakpoint, and exon 5 within the homozygously deleted fragile region. Aberrant transcripts of the FHIT locus were found in approximately 50% of esophageal, stomach, and colon carcinomas.

Acid Anhydride Hydrolases↗
PubMed1996

PTPN13, a fas-associated protein tyrosine phosphatase, is located on the long arm of chromosome 4 at band q21.3.

PTPN13 is a protein tyrosine phosphatase that associates with the C-terminal negative regulatory domain in the Fas (APO-1/CD95) receptor. The PTPN13 protein contains six GLGF repeats that have been found in the rat postsynaptic density protein (PSD-95) and the Drosophila tumor suppressor protein, lethal-(1)-disc-large-1 (dlg-1). The localization of the PTPN13 gene to human chromosome 4q21.3 was determined by both FISH and PCR analysis of somatic cell hybrids. This 4q21.3 chromosomal region contains a gene for autosomal dominant polycystic kidney disease as well as the region frequently deleted in liver and ovarian cancers, suggesting that PTPN13 is a candidate for one of the putative tumor suppressor genes on the long arm of chromosome 4.

Base Sequence↗
PubMed1996

Laparoscopic repair of paraumbilical ventral hernia with increasing size in an obese patient.

We report a case of paraumbilical ventral hernia with increasing size over 1 year which was successfully repaired using laparoscopic techniques. The repair was made using a 1-mm-thick expanded polytetrafluoroethylene patch inserted intraperitoneally and then stapled to the anterior abdominal wall over the defect. This laparoscopic repair is easily accessible, is considered to reduce morbidity and is thus recommended as the first choice of treatment for ventral hernia.

Female↗
PubMed1996

Extreme hyperbilirubinemia induced by endoscopic injection sclerotherapy in a patient with esophageal varices and thalassemia: report of a case.

We describe herein the case of a 57-year-old man with thalassemia who developed acute liver failure after undergoing endoscopic injection sclerotherapy (EIS) to control hemorrhage from a ruptured esophageal varix. The patient, who had been confirmed as having liver cirrhosis due to chronic hepatitis C with thalassemia in 1989, was admitted to our department to undergo EIS for esophageal varices, at which time his serum total bilirubin level was 5.5 mg/dl. As a small amount of hematemesis occurred just after a percutaneous transhepatic portography was performed, emergency EIS was carried out, following which the serum total bilirubin level markedly increased, mainly with a direct fraction, until it reached 70 mg/dl. The patient eventually died from acute liver failure with extreme hyperbilirubinemia on the 27th day after experiencing hematemesis despite all treatment. This unfortunate case demonstrates that sclerotherapy could be an inappropriate method of treatment for patients with hemolytic disease.

Biopsy↗
PubMed1996

Types of methicillin-resistant Staphylococcus aureus associated with high mortality in patients with bacteremia.

Forty-seven strains of methicillin-resistant Staphylococcus aureus (MRSA) isolated from 47 patients with bacteremia were analyzed by chromosomal DNA digestion pattern using pulsed-field gel electrophoresis and evaluated for serological coagulase type, enterotoxin type, and toxic shock syndrome toxin-1 production. The mortality rate was significantly higher in the older patients (> or = 51 years of age) than in the younger patients (< or = 50 years of age) (50% vs. 4%, p = 0.0007). Methicillin-resistant Staphylococcus aureus strains of serological coagulase type II were more likely to be associated with mortality in older patients than were strains of the other types (p = 0.037).

Adolescent↗
PubMed1996

Noninvasive variceal pressure measurement may be useful for predicting effect of sclerotherapy for esophageal varices.

This study assessed the relationship between variceal pressure and morphological findings and hemodynamics of esophageal varices as well as the effect of sclerotherapy. Esophageal variceal pressure was measured in 40 patients with portal hypertension, using a noninvasive method. Esophageal variceal pressures were significantly higher in moderate or large varices than they were in small varices. Variceal pressures were significantly higher in patients with red color signs on the varices than in those without. According to the percutaneous transhepatic portography, the structure of the esophageal varices was classified into two types: the bar type and the palisading type. The maximum variceal pressure was significantly higher in the bar type than in the palisading type. In patients who underwent more than five sessions of sclerotherapy, the variceal pressure was significantly higher than in those receiving less than four sessions. These results suggest that variceal pressure may well reflect the vascular pattern and be useful for predicting the effect of sclerotherapy.

Blood Pressure Determination↗
PubMed1996

Production of an emetic toxin, cereulide, is associated with a specific class of Bacillus cereus.

The emetic toxin (cereulide) of Bacillus cereus was quantified in several isolates of B. cereus and in various food sources. When the emetic toxin was produced, vomiting-type food poisoning was observed in humans. We also found that the H-1 serovar phenotype was strongly associated with the production of cereulide and that none of the isolates that hydrolyzed starch or expressed diarrheal enterotoxin activity produced cereulide.

Bacillus cereus↗
PubMed1996

CETP is a determinant of serum LDL-cholesterol but not HDL-cholesterol in healthy Japanese.

Cholesteryl ester transfer protein (CETP) is one of the factors that regulate plasma levels of HDL-cholesterol. To identify the factors that may regulate CETP activity, and to determine to what extent CETP is correlated with physiologic concentrations of lipoprotein, we performed an epidemiologic study in 586 healthy volunteers (317 males and 269 females mean age 52.2 +/- 10.9 years). CETP activity in these subjects was 192.96 +/- 48.73 (mean +/- S.D.) nmol/ml/h and distributed to a wide range (60-450 nmol/ml/h). Using multiple regression analysis, we found significant positive correlations between CETP activity and LDL-cholesterol (P < 0.03), apolipoprotein (apo) E (P < 0.005) and LCAT activity (P < 0.001). CETP activities showed significant negative correlation with apo A-I (P < 0.03). However, CETP activity showed no significant correlation either with HDL cholesterol or with apo B. One-way layout analysis of variance showed that alcohol drinking and cigarette smoking significantly reduced CETP activity, but there was no significant association between CETP activity and body mass index. Although CETP activities were significantly higher in females than in males (P < 0.001), multiple regression analysis showed no correlation between CETP activity and age in either the males or the females. Our results suggest that CETP activity regulates the concentration of apo A-I and LDL-cholesterol, and that such activity may be influenced by gender, alcohol consumption and cigarette smoking.

Adult↗
PubMed1996

Leukotriene B4 and C4 in cerebrospinal fluid from children with meningitis and febrile seizures.

Concentrations of immunoreactive leukotriene C4 (LTC4) and leukotriene B4 (LTB4) in the cerebrospinal fluid from 18 patients with aseptic meningitis, including 2 patients with encephalitis and 4 patients with febrile seizures, were measured by a sensitive and specific radioimmunoassay; these results were compared with those from control subjects. The concentrations of both LTC4 and LTB4 were elevated significantly in patients with meningitis (LTC4: 115.6 +/- 47.7 pg/ml; LTB4: 1,603.0 +/- 273.5 pg/ml; n = 18) compared to controls (LTC4: 83.2 +/- 21.6 pg/ml; LTB4: 1,219.3 +/- 161.5 pg/ml; n = 12; P < .05 and P < .01, respectively). However, there was no significant increase in LT levels in patients with febrile seizures. These findings suggest that LTs may play an important role in the inflammatory response induced by viral infections of the central nervous system.

Child↗
PubMed1996

Small ultrasonic probes for determination of the depth of superficial esophageal cancer.

BACKGROUND: In esophageal cancer it is important to distinguish between mucosal cancer and cancer invading the submucosa to determine the feasibility of endoscopic mucosal resection. METHODS: Endoscopic ultrasonography using a small probe 2.6 mm in diameter at 15 or 20 MHz frequency was employed to determine the depth of superficial esophageal cancer invasion in 54 patients. Group 1 consisted of 17 cases treated by endoscopic mucosal resection on the basis of ultrasonographic findings. Group II included 37 patients treated by conventional surgery. The resected specimens were compared with ultrasonographic findings. RESULTS: The normal esophageal wall was depicted as having nine layers, the fourth hypoechoic layer (m4) on the high frequency image was confirmed to be the muscularis mucosa. Based on the ultrasound findings, cancer limited to the lamina propria was accurately determined in 84%. In the endoscopic mucosal resection cases, 15 were mucosal cancer whereas 2 cases had microscopic invasion of the submucosa. CONCLUSIONS: High-frequency ultrasound probes were sufficiently accurate for the determination of the depths of invasion of early esophageal cancer to guide the application of endoscopic resection of mucosal cancer.

Aged↗
PubMed1996

Effects of M16209, a new antihyperglycemic agent, on insulin sensitivity in vivo: euglycemic clamp studies in rats.

The effects of M16209 (1-(3-bromobenzo[b]furan-2-ylsulfonyl)hydantoin) on the in vivo insulin sensitivity of rats were studied by euglycemic clamp methods after 1 week of administration (10 or 100 mg/kg/d). M16209 increased both the glucose infusion rate (GIR) and metabolic clearance rate (MCR) of 3-[3H]-glucose, but did not suppress hepatic glucose output. M16209 also increased the [3H]-2-deoxyglucose utilization rate, rate of incorporation of [14C]-glucose into glycogen, and glycolytic flux in the soleus and red gastrocnemius muscles, but not in the extensor digitorum lungus and white gastrocnemius muscles. M16209 affected neither the [3H]-2-deoxyglucose utilization rate nor the rate of incorporation of [14C]-glucose into lipids in epididymal adipose tissue. In the soleus muscle, M16209 decreased glucose-6-phosphate (G6P) and fructose-6-phosphate (F6P) content, but did not affect fructose-1,6-bisphosphate (F-1,6-BP) content. Moreover, M16209 increased glycogen synthase-I activity and fructose-2,6-bisphosphate (F-2,6-BP) content in the soleus muscle. These results suggest that M16209 increases insulin-stimulated glucose uptake in peripheral tissues, particularly oxidative muscles, through potentiation of insulin action on glycogen synthesis and glycolysis. Glycogen synthase and phosphofructokinase (PFK) appear to be major targets of the action of M16209.

Adult↗
PubMed1996

Comparison of DNA fingerprinting by PFGE and PCR-RFLP of the coagulase gene to distinguish MRSA isolates.

Staphylococcus aureus isolates were collected from epidemiologically unrelated clinical sources in Japan between 1991 and 1993. A total of 40 isolates, five each of eight coagulase types, were analysed by polymerase chain reaction (PCR) of the coagulase gene, PCR-restriction fragment length polymorphism (RFLP) after AluI digestion, and pulsed-field gel electrophoresis (PFGE) of chromosomal DNA after SmaI digestion. The efficiency of discrimination among the isolates increased in the order of PCR < PCR-RFLP < PFGE, yielding five, 13 and 31 different types, respectively. To assess the clinical use of these methods, 42 additional methicillin-resistant S. aureus (MRSA) isolates collected from 27 inpatients in a hospital were analysed. PFGE and PCR-RFLP were able to discriminate 11 and four types, respectively. PFGE analysis detected cross-infection between four postoperative patients in an intensive-care unit, and in six neonates in intensive care. We conclude that of the three methods tested, PFGE analysis currently allows the most effective discrimination of MRSA strains.

Bacterial Typing Techniques↗
PubMed1996

Primary B-cell lymphoma of the breast in patient with smoldering type adult T-cell lymphoma.

We report a patient with primary B-cell lymphoma of the breast complicated by smoldering type adult T-cell leukaemia (ATL). A 52-year-old Japanese woman complained of a rapidly enlarging lump in her right breast. She had been diagnosed to have smoldering type ATL since the age of 49. Aspiration cytology and subsequent excisional biopsy revealed B-cell type lymphoma of the breast. A gallium-scintigram showed abnormal accumulation in the bilateral breasts. Radiology was adopted because the lesion was localized only in the breasts and associated with smoldering type ATL. The lesions disappeared after the treatment.

Breast Neoplasms↗
PubMed1996

A case of silent 21-hydroxylase deficiency with persistent adrenal insufficiency after removal of an adrenal incidentaloma.

A case of an adrenal incidentaloma in a 57-year-old man with silent 21-hydroxylase deficiency is reported. Abdominal computed tomography revealed a right adrenal tumour of 6cm in diameter. There was no evidence of adrenal hormone excess. However, after surgical removal of the adrenal tumour, the patient developed acute adrenal insufficiency. Adrenocortical function has remained low ever since surgery. Pathological examination of the tumour revealed a cortical adenoma. On the basis of increased plasma renin activity and serum 17 alpha-hydroxyprogesterone concentration and decreased 21-hydroxylase activity of the adenoma tissue, the patient was diagnosed as having systemic 21-hydroxylase deficiency. There are two possible mechanisms for the persistent adrenal insufficiency; first the residual left adrenal gland may have been originally hypo-functioning for some reason and, second, the left gland may have lost the ability to regenerate following prolonged suppression by the adenoma. In cases of adrenal incidentalomas with 21-hydroxylase deficiency, the indications for surgical removal should be carefully considered.

Adenoma↗