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Y Fujimoto

Publications and source records attributed to Y Fujimoto.

At least 181 records · Page 10Linked to original sources
PubMed1998

[Retropharyngeal node metastasis in cancer of the oropharynx and hypopharynx: analysis of retropharyngeal node dissection regarding preoperative radiographic diagnosis].

In our department, all patients with advanced carcinoma of the oropharynx and hypopharynx are treated by retropharyngeal (RP) node dissection in addition to primary resection and standard neck dissection. Records of 42 patients (11 oropharynx, 29 hypopharynx and 2 retromandibula) who received RP node dissection from 1992 to 1996 in our department were examined for metastasis to RP nodes and for preoperative radiographic diagnosis (MRI or CT). The criteria for radiographic involvement of RP nodes are as follows: a diameter greater than 10mm on axial images or central necrosis within the nodal substance. Of the 42 patients, 6 (14.3%) had pathologically positive RP nodes and of those 6 patients, 5 were able to be diagnosed preoperatively by either CT scan or MRI. Results of radiographic diagnosis (MRI or CT) were as follows: by CT scan the sensitivity, specificity and accuracy were all 100% and by MRI the sensitivity, specificity and accuracy were 83.3%, 100% and 97.0% respectively. It is our conclusion that preoperative radiographic diagnosis (MRI or CT) is very useful and effective for diagnosis of metastasis to RP nodes.

Adult↗
PubMed1998

[An immunohistochemical study of RB tumor suppressor gene protein and bcl-2 gene protein in carcinomas of the thyroid gland].

The expression of RB and bcl-2 proteins was investigated in 135 thyroid carcinomas (130 papillary carcinomas and five follicular carcinomas) by the immunohistochemical technique with RB and bcl-2 monoclonal antibodies. The results were as follows: 1) RB protein nuclear staining was shown in 117 of the 135 thyroid carcinomas (87%). Bcl-2 protein staining was shown in 82 of the carcinomas (61%). 2) There was a higher incidence of recurrence in RB-negative cases than in RB-positive cases (chi 2 test p = 0.001). But there is no significant relationship between the incidence of recurrence and the results of bcl-2 staining (chi 2 test p = 0.287). 3) The expression of RB protein was related to age and clinical N and M categories. Bcl-2 protein expression was related to clinical T categories. 4) The 10-year overall survival rate for RB-positive patients was higher than that for negative patients (long-rank test p < 0.0001). But the survival rate was not associated with bcl-2 expression (log-rank test p = 0.3). Our results suggest that assessment of RB protein expression by the immunohistochemical technique may be useful to determine the possibility of recurrence and to predict the outcome of thyroid carcinomas. We think that assessment of RB protein expression by the immunohistochemical technique can be applied as a more sensitive prognostic factor.

Adenocarcinoma, Follicular↗
PubMed1998

Living-related small bowel transplantation: the first case in Japan.

Intestinal failure has been managed with total parenteral nutrition (TPN), but occasionally complications such as obliteration of venous access or liver dysfunction occur. To overcome such complications, small bowel transplantation (SBT) was introduced. Since the introduction of tacrolimus in 1990, successful SBT cases have been reported. We performed SBT by using a living donor for a child with short bowel syndrome. The recipient (2.5 years old, male) was born with intestinal necrosis secondary to midgut volvulus. The length of the remaining small bowel was 30 cm. While being managed with TPN, his venous access gradually obliterated. Long-term survival could not be expected because of the difficulty in securing TPN access. The donor was his mother, whose distal ileum (100 cm) was used as a graft. The immunosuppression regimen consisted of tacrolimus, steroids and azathioprine. Three episodes of severe rejection and subsequent episodes of viral (EBV, CMV) infection were managed with steroid pulse therapy and antiviral drugs, respectively. The recipient suffered from anastomotic stenosis, and an operation was performed 13 months after transplantation to resect the stenotic segment. However, the patient died of Pneumocystis carinii pneumonia 16 months after transplantation. We conclude that organ retrieval from a living donor can be performed safely for SBT, but further study of the management of rejection as well as of viral infection is necessary, as it is for non-living-related SBT.

Adult↗
PubMed1998

[Alteration of genomic structure and/or expression of cancer associated genes in hepatocellular carcinoma].

Cancer is thought to arise from the accumulation of several genetic mutations in a single cell. These include integration of viral genomes, activation of protooncogenes and inactivation of tumor suppressor genes. HCC is one of the most common cancers in Asia and Africa. Various studies have revealed its association with hepatitis B or C viral infection. While activation of known protooncogenes, such as ras genes does not seem to play an important role, frequent allelic loss on specific chromosomal arms, 4q, 13q, 16q and 17p, indicates that dysfunction of diverse tumor suppressor genes located on these chromosome arms is involved in the development of HCC. An informative p53 mutational spectrum of frequent G to T transversions in codon 249 is found in HCCs from either Qidong, People's Republic of China, or southern Africa. This observation links exposure to aflatoxin B1, a known cancer risk factor in these geographic regions. Recently, we found that expression of syndecan-1, which is a transmembrane heparan sulfate proteoglycan involved in cell matrix interactions and growth factor bindings, was inversely associated with metastatic potential in human hepatocellular carcinoma as like nm23-H1 expression was. Transfection with syndecan-1 gene suppresses invasive activity of hepatoma cells. These data support our hypothesis that syndecan-1 is one of important metastasis suppressor factors in hepatoma cells. PR-39 is a proline-rich antimicrobial peptide which was isolated from a pig small intestine and has been reported to induced syndecan-1 on mouse mesenchymal cells. Transfection with PR-39 gene caused induction of syndecan-1 and altered invasive phenotype and actin structure on hepatoma cells. Syndecan-1 and PR-39 may serve as a basis for design of drug or gene therapy effective against metastasis of hepatocellular carcinomas.

Amino Acid Sequence↗
PubMed1998

Temperature-dependent lipid peroxidation of rat brain homogenate.

When rat brain homogenate was incubated without adding iron, lipid peroxidation occurred temperature dependently between 27 degrees C and 42 degrees C. When homogenates of liver and heart were incubated under the same conditions, lipid peroxidation did not occur. The brain, compared with other organs, seems to be very vulnerable to oxidative damage with fever. Catalase promoted lipid peroxidation. The ability of dihydrolipoic acid and alpha-tocopherol to inhibit lipid peroxidation was very weak. In contrast, iron chelators, such as bathophenanthroline, desferrioxamine and EDTA, strongly inhibited lipid peroxidation, indicating that endogenous iron is involved in lipid peroxidation. Dialysis of brain homogenate depressed the temperature-dependent lipid peroxidation by about 30%. Then, the iron content of the homogenate decreased by about 35%. On the other hand, dialysis of EDTA-treated homogenate completely depressed the lipid peroxidation and the iron content of the homogenate decreased by about 87%. Adding iron to the homogenate dialyzed after EDTA treatment remarkably increased the lipid peroxidation, but the peroxidation reaction proceeded temperature independently. Our results suggest that endogenous iron, which may bind to cell components, causes temperature dependent lipid peroxidation by a site-specific mechanism.

Animals↗
PubMed1997

Reduced expression of syndecan-1 in human hepatocellular carcinoma with high metastatic potential.

Syndecans comprise a gene family of transmembrane proteoglycans that regulate cellular behavior through interactions with various effectors, including heparin-binding growth factors and insoluble matrix components. Syndecan-1, the most extensively studied, localizes in epithelial cells and has been shown to present in normal hepatocytes. However, little is known about the change of syndecan-1 expression in human hepatocellular carcinoma (HCC). We investigated syndecan-1-protein expression by immunohistochemistry in 57 HCC tissue samples. Syndecan-1 gene expression was also determined. Syndecan-1 protein was expressed in cytoplasm and cell membrane of the hepatocytes and in the bile duct epithelial cells of liver with underlying hepatitis and cirrhosis. Conversely, among 57 HCC tissues, 39 HCC (68.4%) showed negative staining; 50% of well-differentiated HCC showed positive staining, whereas 82.4% of poorly differentiated HCC were negative. Loss of syndecan-1-protein expression was more prevalent in HCC with intra-hepatic metastasis (85.2%) than those without metastasis (48.0%). Similarly, syndecan-1 expression was significantly reduced in HCC with extra-hepatic metastasis (91.7%) as compared with the HCC without extra-hepatic metastasis (62.2%). The gene expression of syndecan-1 was significantly lower in HCC tissue than that in non-tumoral liver tissue. In 2 human HCC cell lines with poorly differentiated phenotype, HLE and HLF, syndecan-1 expression was markedly decreased both at the mRNA and the protein levels. These results suggest that the loss of syndecan-1 expression is a characteristic feature of HCC with high metastatic potential.

Antibody Specificity↗
PubMed1997

CD26/dipeptidyl peptidase IV does not work as an adenosine deaminase-binding protein in rat cells.

In this paper, we describe further characterization of the membrane-associated molecule CD26/dipeptidyl peptidase IV (DPP IV), which is said to be adenosine deaminase-binding protein (ADA-bp) in humans, to clarify its association with ADA in rat immune cells. For this purpose, we used three types of rats: DPP IV+ rats; DPP IV- rats, which lack enzyme activity and immunological reactivity of DPP IV; and ADA- rats, which have reduced ADA activity due to continuous peritoneal injection of 2'-DCF, a potent inhibitor of ADA. ADA existed in the cells of DPP IV+ and DPP IV- rats, but it did not exist on the cell surface in either rat. ADA- rats showed a decrease in ADA activity and in the number of immune cells, but no effect on DPP IV was observed. These data suggest that in rats, in contrast to humans, DPP IV does not exist as ADA-bp.

Adenosine Deaminase↗
PubMed1997

Characteristics of 161 patients with cardiac tumors diagnosed during 1993 and 1994 in Japan.

We investigated clinical and pathologic characteristics of 161 patients with primary or secondary cardiac tumors diagnosed between 1993 and 1994 in Japan. The increased use of cardiovascular imaging, especially echocardiography, contributed to the early identification of small cardiac tumors, resulting in a reduction of the serious complications such as embolization.

Adolescent↗
PubMed1997

Peroxynitrite induces the conversion of xanthine dehydrogenase to oxidase in rabbit liver.

Effect of peroxynitrite (ONOO-) on the conversion of xanthine dehydrogenase to oxidase in rabbit liver was examined. ONOO- (25-200 microM) induced the conversion of xanthine dehydrogenase to oxidase in a dose-dependent manner. The addition of hydroxyl radical scavengers (mannitol and dimethyl sulfoxide) gave no alteration in the ONOO(-)-induced conversion of xanthine dehydrogenase to oxidase, implying that the action of ONOO- is not due to hydroxyl radicals which may be formed from ONOO-. The experiment utilizing dithiothreitol also revealed that the action of ONOO- might be due to oxidation of sulfhydryl group of xanthine dehydrogenase. These results suggest that ONOO- has the potential to convert xanthine dehydrogenase to oxidase, and that this effect may be correlated with cytotoxic actions of ONOO-.

Animals↗
PubMed1997

Comparison of the hydrolysis of the three types of natriuretic peptides by human kidney neutral endopeptidase 24.11.

The degradation of 3 human natriuretic peptides by human kidney neutral endopeptidase 24.11 has been investigated. The studies revealed that hANP-28 and hCNP-22 are the preferred substrates, whereas hBNP-32 is not. The enzyme has been known to inactivate hANP-28 from cleavage at the Cys-Phe bond at the beginning of its ring structure. Analysis of the cleavage sites of each peptide indicated that the initial cleavage site of hCNP-22 is analogous to that of hANP-28. The Cys-Phe bond of hBNP-32 was insensitive to this enzymatic cleavage. We speculate that the stability of hBNP-32 may result from the insusceptibility of its Cys-Phe bond at the beginning of the ring structure.

Amino Acid Sequence↗
PubMed1997

Effect of regional myocardial perfusion abnormalities on regional myocardial early diastolic function in patients with hypertrophic cardiomyopathy.

Nonuniform hypertrophy of the left ventricle is an important factor in regional diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM). However, the effect of myocardial perfusion abnormalities on regional diastolic dysfunction has not been established in patients with HCM. We investigated the relationship between regional myocardial perfusion abnormalities and regional early diastolic function in 31 patients with HCM and 8 control patients. Short-axis images of the left ventricle recorded by cine magnetic resonance imaging were divided into ten blocks. The time-to-peak-wall-thickness-thinning rate (TPWR) and the wall thickness were measured in each block. Of the 310 blocks from the patients with HCM, 242 (78%) showed normal thallium-201 uptake (group 1), 40 (13%) showed slightly decreased uptake (group 2), and 28 (9%) showed markedly decreased uptake (group 3). There was no difference in the regional wall thickness among the three groups. The TPWR was longer in patients with HCM than in control patients. It was significantly longer in group 3 (190+/-45ms) than in group 1 (167+/-36 ms) and group 2 (160+/-31 ms). (P < 0.01). The linear regression slope of the relationship between the TPWR and the regional wall thickness was significantly steeper in group 3 than in groups 1 and 2 (P < 0.05). In conclusion, abnormalities in regional myocardial perfusion, in addition to regional hypertrophy, contributed to the regional early diastolic dysfunction in patients with HCM.

Adult↗
PubMed1997

Novel fatty acid esters of (7E, 12E, 18R, 20Z)-variabilin from the marine sponge Ircinia felix.

The methanolic extract of the marine sponge Ircinia felix has yielded nine novel fatty acid esters, (7E, 12E, 18R, 20Z)-variabilin (5Z, 9Z)-22-methyltricosadienoate, (7E, 12E, 18R, 20Z)-variabilin (5Z, 9Z)-tetracosadienoate, (7E, 12E, 18R, 20Z)-variabilin hexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 10-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 15-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 14-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 9-octadecenoate, (7E, 12E, 18R, 20Z)-variabilin octadecanoate, and (7E, 12E, 18R, 20Z)-variabilin 2,11-dimethyloctadecanoate, along with the recently described (7E, 12E, 18R, 20Z)-variabilin 11-methyloctadecanoate. The characterization of the new fatty acids (5Z, 9Z)-22-methyltricosadienoic and 2,11-dimethyloctadecanoic acids is also described. The chemical structures were determined by extensive spectroscopic, chromatographic, and chemical analyses.

Animals↗
PubMed1997

Isolated dural metastasis from colon cancer.

We report a case of isolated dural metastasis from colon cancer. Neuroradiologic and intraoperative findings indicated that the tumor was extra-axial, and histopathologic examination resulted in the correct diagnosis. Notable neuroradiologic findings of the present dural-based tumor were: diploic fat MRI signal disappeared in the tumor associated calvaria where bony change was absent on bone-window CT; abnormal subgaleal and epidural tissues were seen on MRI, both of which contained clusters of adenocarcinoma cells histopathologically. These findings suggest an infiltrative, malignant character, and help to differentiate between benign and malignant dural-based tumors.

Adenocarcinoma↗
PubMed1997

Responses of catecholamines, renin-angiotensin system, and atrial natriuretic peptide to exercise in untrained men and women.

1. Plasma norepinephrine (NE), epinephrine (E), renin activity (PRA), angiotensin II (ATII), aldosterone (ALD), and atrial natriuretic peptide (ANP) were measured in 20 male and 15 female subjects during submaximal treadmill test. 2. Exercise duration was not different between the two groups (male vs. female: 13.4 +/- 0.8 min vs. 11.6 +/- 0.7 min, ns). Female subjects had higher heart rate during exercise, while systolic blood pressure at peak exercise was higher in male subjects. 3. Plasma NE, E, ANP, and ATII responses were comparable between male and female subjects, but PRA both at rest and during exercise and ALD at rest were significantly higher in male subjects. 4. Cardiac responses to submaximal exercise were different between male and female subjects, but neurohormonal responses were comparable between the two groups except for the high PRA at rest and during exercise and high plasma ALD at rest in male subjects.

Adult↗
PubMed1997

Effects of nonanal, trans-2-nonenal and 4-hydroxy-2,3-trans-nonenal on cyclooxygenase and 12-lipoxygenase metabolism of arachidonic acid in rabbit platelets.

The effects of nonanal, trans-2-nonenal and 4-hydroxy-2,3-trans-nonenal on the formation of thromboxane B2 (TXB2), 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) from exogenous arachidonic acid in washed rabbit platelets were examined. Nonanal and trans-2-nonenal at concentrations ranging from 0.25 to 2 microM inhibited TXB2, HHT and 12-HETE formation, reducing the amounts of these three arachidonic acid metabolites by 50% at nonanal and trans-2-nonenal concentrations of approximately 0.25 microM. The inhibition of TXB2, HHT and 12-HETE formation induced by 4-hydroxy-2,3-trans-nonenal (50% inhibition by 4-hydroxy-2,3-trans-nonenal at a concentration of approximately 100 microM) was 400 times weaker than that induced by nonanal and trans-2-nonenal. These results suggest that nonanal and trans-2-nonenal can be modulators of platelet arachidonic acid metabolism by affecting the activity of cyclooxygenase and 12-lipoxygenase.

Aldehydes↗
PubMed1997

Sinus pericranii: neuroradiologic findings and clinical management.

We report an 11-year-old boy with a sinus pericranii. Magnetic resonance images demonstrated a small hole in the cranium underneath the subcutaneous mass. Magnetic resonance angiography (MRA) with sequential two-dimensional time-of-flight (2D-TOF) method demonstrated that the venous flow via the sinus pericranii was directed from the intra- to the extracranial venous system (the drainer type). This was confirmed by a combination of conventional cerebral angiography and percutaneous sinography. We advocate that both the correct diagnosis and classification of sinus pericranii can be established with a combination of current noninvasive neuroradiologic studies, especially for the pediatric age group. MRA with the 2D-TOF method is useful in the assessment of this venous anomaly.

Cerebral Veins↗