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S Miyamoto

Publications and source records attributed to S Miyamoto.

At least 253 records · Page 14Linked to original sources
PubMed1998

Actin-filaments localize on the sorting endosomes of 3Y1 fibroblastic cells.

By immunofluorescence microscopic observation, monoclonal and polyclonal antibodies against a synthetic actin C-terminal peptide were found to stain too colloguial, ambiguous punctuate structures distributed throughout the cytoplasm of 3Y1 cells, independently of actin stress fibers. Antibody against rab5, a small GTP binding protein of the sorting endosome, and anti-actin antibody co-stained these punctuate structures. On the other hand, transferrin receptor, a well characterized maker of the sorting and recycling endosomes, colocalized with actin on the vesicular structures at the cell peripheral region but not at the perinuclear area where the recycling endosome localized. These observations suggest that actin molecules localize on the sorting endosomes. Tropomyosin, F-actin binding protein, also colocalized with actin on the sorting endosomes. From these results, we proposed that actin-filaments with tropomyosin constitute the membrane skeleton on the sorting endosome surface. This article is the first report to show that actin-filaments localize on the intact endosomes.

Actins↗
PubMed1998

Cloning and nucleotide sequence of the gene encoding a serine proteinase inhibitor named marinostatin from a marine bacterium, Alteromonas sp. strain B-10-31.

The gene (mstI) encoding a serine proteinase inhibitor named marinostatin from marine Alteromonas sp. strain B-10-31 was cloned and its nucleotide sequence was analyzed. A short open reading frame of 192 bp encoded 63 amino acids with a molecular weight of 6,985. Furthermore, the initial product of marinostatin (marinostatin L) was purified and its amino acid sequence was analyzed. These results indicate that marinostatin is produced as a unique precursor consisting of the mature peptide and the leader peptide for an ATP-binding cassette (ABC) transporter, and furthermore the initial product of marinostatin is dehydrated and processed by proteolysis to give homologous forms of marinostatin.

ATP-Binding Cassette Transporters↗
PubMed1998

Synthesis of a novel phosphate ester of a vitamin E derivative and its antioxidative activity.

A novel phosphate ester containing a chromanol structure was synthesized from 1,2-diacyl-sn-glycero-3-phospho-2'-hydroxyethyl-2',5',7',8'-tetramethyl- 6' -hydroxychroman (PCh) by hydrolysis catalyzed by phospholipase C from Bacillus cereus. The structure of the product was found by spectral analyses to be 2-(2',5',7',8'-tetramethyl-6'-hydroxychromanyl)ethylphosphate++ + (Ch-P). Ch-P was highly soluble in the aqueous phase at neutral pH values and exerted higher antioxidative activity than alpha-tocopherol and PCh in the Fe(III)/ascorbic acid-catalyzed peroxidation of a fish oil emulsion and the autoxidation of a rat brain homogenate.

Animals↗
PubMed1998

The long-term effect of menopause on postmenopausal bone loss in Japanese women: results from a prospective study.

The aim of this study was to elucidate perimenopausal bone loss in relation to menstrual conditions and to investigate the long-term effect of menopause on bone loss in aged women. The rate of change in bone mineral density (BMD) was measured twice at an exact interval of 12 months by dual-energy X-ray absorptiometry (DXA) at the lumbar spine in 176 pre- and postmenopausal healthy women 41-65 years of age. Serum follicle-stimulating hormone, intact and N-fragment osteocalcin (OC), three types of vitamin D3, parathyroid hormone (PTH), and calcitonin were also determined. Women who exercised regularly or had anatomical changes at the lumbar spine were excluded from this study. The subjects were divided into eight groups based on their menstrual status and years since menopause. Annual bone loss at the lumbar spine of premenopausal women with regular menstruation was -0.2+/-1.9% (95% confidence interval, -0.9 approximately -0.4%) and was not statistically different from zero, while that of women with irregular menstruation or at menopausal transition was -2.1+/-3.4% (-3.4 approximately -0.8%), and -3.3+/-2.3% (-5.2 approximately -0.3%), respectively, and was significantly different from zero. Serum OC levels of women at menopausal transition were significantly higher than those of women with regular menstruation, suggesting that bone loss had commenced in these women. The rate of annual change in BMD of women who were menopausal for 1-3, 4-6, 10-12, and more than 13 years was -3.1+/-4.0% (-4.7 approximately -1.5%), -1.2+/-2.6% (-2.2 approximately -0.2%), -1.0+/-3.0% (-2.3 approximately -0.3%), and -2.3+/-2.1% (-3.7 approximately -1.0%), respectively, and was significantly less than zero. But the annual bone loss of women who were menopausal for 7-9 years was -1.5+/-2.6% (-3.0 approximately -0.1%) and was not statistically significant from zero. These results indicate that postmenopausal women lose BMD in two phases. The early bone loss is rapid and commences during irregular menstruation, then is attenuated within 6 years after the onset of menopause. The second bone loss commences after the attenuation of the first bone loss. Among bone metabolic hormones, intact PTH alone showed an age-related increase and was suggested as being a causal factor of bone loss in women who were menopausal for 13 years or more.

Absorptiometry, Photon↗
PubMed1998

Direct anastomotic bypass for cerebrovascular moyamoya disease.

Therapeutic result and pitfalls in the surgical treatment of cerebrovascular moyamoya disease are evaluated. During the recent 15 years, 268 patients with moyamoya disease have been treated in our clinic. Among them, 238 patients showed ischemic symptoms. Superficial temporal artery to middle cerebral artery anastomoses combined with temporal muscle grafting (encephalo-myo-synangiosis) were performed for most of the cases. Complete remission and clinical improvement were obtained in 34.0% and 64.2% of the patients, respectively. Symptomatic aggravation due to ischemic complication followed the operation in five patients (1.9%). Normocapnic control during general anesthesia with sufficient hydration is essential to avoid perioperative ischemic complications. Omental graft was performed in 16 patients. In 13 patients, omental graft was performed for the progressing ischemia in the posterior cerebral artery or anterior cerebral artery distribution. In the other three patients, omental graft was used for marked brain atrophy.

Anastomosis, Surgical↗
PubMed1998

Integrin signaling: cytoskeletal complexes, MAP kinase activation, and regulation of gene expression.

Members of the integrin family of adhesion receptors mediate interactions of cells with the extracellular matrix. Besides their role in tissue morphogenesis by anchorage of cells to basement membranes and migration along extracellular matrix proteins, integrins are thought to play a key role in mediating the control of gene expression by the extracellular matrix. Studies over the past 10 years have shown that integrin-mediated cell adhesion can trigger signal transduction cascades involving translocation of proteins and protein tyrosine phosphorylation events. In this review, we discuss approaches used in our lab to study early events in integrin signalling as well as further downstream changes.

Animals↗
PubMed1998

Role of transforming growth factor-beta1 in the pathogenesis of moyamoya disease.

OBJECT: Prominent features of moyamoya disease are intimal thickening of the cerebral arterial trunks and abundant angiogenesis for collateral blood supplies, but its pathogenesis is still unknown. The aim of this study was to test the possibility that transforming growth factor-beta1 (TGFbeta1) may play a role in the pathogenesis of moyamoya disease. METHODS: The authors used reverse transcription-polymerase chain reaction to analyze the expression level of TGFbeta1 in smooth-muscle cells cultured from the superficial temporal arteries (STAs) and measured the serum level of TGFbeta1 by using enzyme-linked immunosorbent assay. Although the STA is not predominantly involved with moyamoya disease, it has been used in studies of the pathogenesis of this disease. In this report, the STAs from six patients with moyamoya disease and four with arteriosclerotic cerebrovascular disease, along with sera from 14 patients with moyamoya disease and 10 normal healthy volunteers, were studied. The expression of TGFbeta1 was significantly higher in cultured smooth-muscle cells derived from the STAs of patients with moyamoya disease than in those derived from the STAs of patients with arteriosclerotic cerebrovascular disease (p < 0.05). The serum level of TGFbeta1 was also significantly higher in patients with moyamoya disease than in controls (p < 0.0005). CONCLUSIONS: Taking into account the functional roles of TGFbeta1 in the expression of connective tissue genes and angiogenesis, these investigators suggest that TGFbeta1 is associated with the pathogenesis of moyamoya disease, including abundant neovascularization, although their findings do not necessarily mean that TGFbeta1 is a causative factor in this disease.

Adolescent↗
PubMed1998

[Preoperative CEA level predicts outcomes of hepatic resection for liver metastases from colorectal cancer].

We analyzed patients receiving hepatic resection for liver metastases from colorectal cancer to determine prognostic factors. Seventy-one patients underwent curative hepatic resection for liver metastases and 32 of them were treated with arterial infusion chemotherapy (AIC) using implantable port. Five-year survival rates in the AIC group and non-AIC group calculated by the method of Kaplan-Meier were 43% and 22%, respectively (p < 0.01, logrank test). By multivariate analysis calculated by the Cox proportional hazard model, the preoperative CEA level (cut point 10 ng/dl) and existence of AIC predicted survival.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

[Three cases of Pseudomyxoma peritonei treated with intraperitoneal inoculation of cisplatin through an implantable port system].

Three patients with Pseudomyxoma peritonei were treated with intraperitoneal chemotherapy through an implantable port system which had been used subcutaneously. Three patients were given 100 mg of cisplatin for intraperitoneal chemotherapy and adjuvant chemotherapy was needed for only one of them. An adjuvant chemotherapy through an implantable port is an easy method and a useful therapy.

Aged↗
PubMed1998

Measurement of platelet microparticles during cardiopulmonary bypass by means of captured ELISA for GPIIb/IIIa.

A captured enzyme-linked immunosorbent assay (ELISA) using the disintegrin, kistrin, is described and used to measure platelet microparticles (PMP) generated during open heart surgery. This ELISA detects 75 ng/ml of glycoprotein IIb/IIIa (GPIIa/IIIa) in solution and is more sensitive and less variable than flow cytometry and radioimmunoassay. By ELISA, mean values of GPIIb/IIIa in PMP are 14.2 +/- 7.9 microg/ml for outdated platelets and 0.28 +/- 0.1 microg/ml in fresh blood from healthy donors. Normal washed platelets (10(8)) contain 8.8 microg of GPIIb/IIIa. In 12 cardiac surgical patients, PMP measured by ELISA significantly increased (p = 0.039) to 0.58 +/- 0.3 microg/ml at the end of cardiopulmonary bypass, but the increase measured by flow cytometry (1207 to 1447 events in PMP gate) was not significant. Neither heparin nor protamine alter PMP. After cardiopulmonary bypass, PMP concentrations return to baseline values before protamine is given. Concentrations of PMP in pericardial blood are greater than in simultaneous perfusate. This ELISA is more sensitive and accurate than alternate methods for measuring PMP and shows the PMP production and rapid clearance during open cardiac surgery.

Cardiopulmonary Bypass↗
PubMed1998

[Determinants of long-term outcome for operative survivors of acute aortic dissection].

Predictability of aorta-related complications and survival was examined in 79 operative survivors of acute aortic dissection. Follow-up was 94.9% complete and totaled 458 patient-years. Actuarial survival was 93 +/- 3% (+/- S.E.) (n = 43) at 5 years, and 74 +/- 8% (n = 13) at 10 years. Survival was significantly lower in patients having neurological complication. Freedom from aorta-related complications was 82 +/- 5% (n = 37) at 5 years, and 67 +/- 8% (n = 11) at 10 years. Multivariate Cox regression analysis identified residual entry and leak on anastomotic site as independent predictors of aorta-related complications. We conclude that in the treatment of acute aortic dissections, reducing the incidence of residual entry and leak on anastomotic site improves long-term outcome.

Acute Disease↗
PubMed1998

Pentosidine in synovial fluid in osteoarthritis and rheumatoid arthritis: relationship with disease activity in rheumatoid arthritis.

OBJECTIVE: Pentosidine is an advanced glycation endproduct formed by glycosylation and oxidation. Our aim was to develop a means to measure pentosidine in synovial fluid (SF), and to compare its concentration in SF in patients with osteoarthritis (OA) and rheumatoid arthritis (RA), and to investigate the relationship between its concentration in SF and the disease activity of RA. METHODS: SF was collected from knee joints in 31 patients with RA and 40 with OA, who had hydrarthrosis. One patient with RA and 7 with OA who had the complication of diabetes mellitus or chronic renal failure made up the DM/CRF group, and the remaining patients made up the RA group (n = 30) and the OA group (n = 33). Pentosidine was measured by the direct HPLC method with column switching after hydrolysis of SF. RESULTS: Pentosidine was detected in all SF and was greater in RA (83.9 +/- 46.0 nmol/l, mean +/- SD) than in OA (40.1 +/- 19.6 nmol/l). Three DM/CRF patients undergoing hemodialysis had markedly high pentosidine levels (482.5 +/- 280.8 nmol/l). There was a significant correlation between pentosidine and C-reactive protein (CRP), erythrocyte sedimentation rate, and Lansbury Index (p < 0.01). Patients with RA were divided into high and low activity groups according to the CRP and Lansbury Index. Pentosidine was significantly higher in the high activity group (CRP > or = 2.0 mg/dl and Lansbury Index > or = 50%) than in the low activity group (CRP < 2.0 and/or Lansbury Index < 50) (100.9 +/- 42.8 vs 58.5 +/- 39.6 nmol/; p = 0.0013). CONCLUSION: Pentosidine in synovial fluid was higher in RA than in OA. Pentosidine levels in SF were related to the disease activity in RA.

Adult↗
PubMed1998

Interaction of leukocytes with platelet microparticles derived from outdated platelet concentrates.

Platelet microparticles (PMP) were isolated from outdated platelets by a combination of differential centrifugation and gel filtration, and the concentration of PMP was expressed in the equivalent of GPIIb/IIIa complex measured by captured ELISA. PMP bound to isolated neutrophils and macrophages in a dose-dependent manner, but they did not bind to lymphocytes. Incubation of PMP with neutrophils did not activate these cells as measured by up-regulation of Mac-1, release of human granulocyte elastase, and calcium mobilization. Incubation of PMP with macrophages did not enhance IL-8 production and the oxygen burst but slightly and significantly increased production of MCP-1. After 10 min incubation of PMP with macrophages, an increase of GPIIb/IIIa antigen was observed suggesting that PMP may be endocytosed by macrophages. In conclusion, PMP bind to leukocytes, but, in contrast to activated platelets, do not play a significant role in leukocyte activation.

Biomarkers↗