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T Miyazaki

Publications and source records attributed to T Miyazaki.

At least 469 records · Page 26Linked to original sources
PubMed1994

[Reversal of myelofibrosis is an important pre-transplant factor for bone marrow grafting--a successful case of allogeneic bone marrow transplantation for an acute megakaryoblastic leukemia].

We report a successful ereated case of acute megakaryoblastic leukemia (AMKL) with myelofibrosis (MF), which achieved a disease free condition, with disappearance of MF, for over 24 months after allogeneic bone marrow transplantation (BMT) and summarized cases of MF receiving BMT reported in Japan to evaluate the influence of MF on engraftment of bone marrow (BM). A 40-year-old man was admitted on Jan. 29, 1991 due to anemia and thrombocytopenia. BM aspiration resulted in a dry tap and MF and cells stained positive with anti-GPIIb/IIIa (CD41a) antibody were demonstrated by BM the biopsy specimen. Complete remission was achieved by multi-drug chemotherapy including behenoylcytosine arabinoside, etoposide, mitoxantrone and prednisolone (PLS). After preconditioning with little BU+CY, BMT was performed from an HLA-identical brother on Jan. 16, 1992. From day 9 of post BMT, acute skin graft versus host disease (grade 1) was observed, which was controlled by 60 mg/day of PSL. Engraftment was achieved on day 12. Although cystitis developed, he was discharged on Apr. 5, 1992 and remains disease free. Including the present case, seven allogeneic BMT patient with MF have been reported so far in Japan. Four cases in whom MF recovered before BMT showed better results than other three cases that still showed MF at BMT. Reversal of MF seems to be a favorable pre-transplant factor for successful BMT in patients with MF.

Adult↗
PubMed1994

[Clinical application of gene technology to monitor bone marrow transplantation].

We assessed the origin of peripheral blood cells and bone marrow cells obtained from 15 patients after allogeneic bone marrow transplantation (allo BMT) by sensitive two-step polymerase chain reaction (PCR) amplification of MCT118, a variable number of tandem repeats regions (VNTR), that can be used to detect the DNA pattern of a minor cell population of only 1% without using radioisotopes. Mixed chimerism(MC) was detected in the haematopoietic cells of 3 patients. Two patients developed relapse of leukaemia after the detection of MC and one patient died of bone marrow hypoplasia 7 months after BMT. These findings indicate the clinical usefulness of this method to monitor patients with MC. Also, we analyzed cytokine gene expression in peripheral blood mononuclear cells during the development of graft-versus-host disease (GVHD) in patients who underwent allo BMT using a semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of interleukin(IL)-1 beta, IL-6, and tumor necrosis factor (TNF)-alpha mRNA was increased during the development of GVHD and the degree of this increment depended on the severity of the disease. These findings suggest that IL-1 beta, IL-6, and TNF-alpha produced by peripheral blood mononuclear cells play an important role in the development of GVHD. Therefore, analysis of MC and cytokine mRNA expression using the PCR technique after allogeneic bone marrow transplantation provide important information for treatment and monitoring of marrow transplant patients.

Adolescent↗
PubMed1994

Cystic renal cell carcinoma. Imaging findings with pathologic correlation.

Twenty-seven cystic renal cell carcinomas (RCC) in 23 patients were analyzed radiologically and histologically. They were classified into 4 histopathologic growth patterns: a) multilocular (n = 15, 9 with macrocystic and 6 with microcystic components); b) unilocular (n = 3); c) cystic necrosis (n = 9); and d) tumors originating in the wall of a simple cyst (n = 0). Macrocystic multilocular RCC showed multiloculated configuration on ultrasound and contrast enhanced CT. Angiography revealed neovascularity peripherally or within the tumor (7/9 tumors). Microcystic multilocular RCC did not fulfill the criterion for a cystic mass on ultrasound: they were irregularly hyperechoic. There was little enhancement on postcontrast CT and only slight neovascularity on angiography. Unilocular RCC showed a cystic mass with an irregular wall or mural nodules on ultrasound and contrast enhanced CT. Necrotic RCC showed various sonographic findings from anechoic to irregular echoic. The appearance on CT varied from cystic with mural nodules to a multiloculated or irregular architecture. Neovascularity was seen in the periphery in 8 of 9 tumors. Clinically, this type seemed to be the most aggressive.

Adult↗
PubMed1994

[A case of Salmonella osteomyelitis of the rib].

Salmonella osteomyelitis is a rare disease occurring at a frequency of less than 1% of all cases of osteomyelitis, we report a case of salmonella osteomyelitis of the rib, which was hard to differentiate from chest wall tumor. A 40-year-old man without gastrointestinal symptoms was admitted to our hospital for swelling of the right mammary region. It was suggestive of inflammatory pseudotumor because the swelling diminished, and we could not establish a diagnosis of abscess by scintigraphy with gallium-67 or by computed tomogram (CT). Drainage was carried out in the chest and about 10 ml of pus was removed. A culture was taken from the pus, revealing salmonella enteritidis, he was treated by local wound care and ABPC (aminobenzyl-penicillin). The open wound became sterile in 40 days, and was closed 46 days after being opened for drainage.

Adult↗
PubMed1994

Quantification of serum 1,5-anhydroglucitol in uremic and diabetic patients by liquid chromatography/mass spectrometry.

We developed a new method for measuring serum 1,5-anhydroglucitol (1,5-AG), using liquid chromatography/atmospheric pressure chemical-ionization mass spectrometry (LC/MS). With this method we measured serum 1,5-AG concentrations in uremic and diabetic patients and compared these values with those determined by an enzymatic method. Serum 1,5-AG concentrations were significantly less in the undialyzed and dialyzed uremic patients and in diabetic patients; the values in the dialyzed patients decreased after hemodialysis. In uremic patients with high concentrations of serum myo-inositol, the 1,5-AG values determined by LC/MS were significantly lower than those determined enzymatically. There was no significant correlation between 1,5-AG and fructosamine in the uremic patients. These results demonstrate that serum 1,5-AG cannot be used as an index for glycemic control in uremic patients and that the LC/MS method is indicated in uremic patients with high concentrations of myo-inositol.

Adult↗
PubMed1993

Regulation of activity levels of glycolipid sulfotransferases by transforming growth factor alpha in renal cell carcinoma cells.

Accumulation of sulfolipids associated with markedly elevated levels of glycolipid sulfotransferase activities was previously demonstrated in human renal cell carcinoma cells. To explore the regulation mechanisms of sulfoglycolipid synthesis in renal cancer, effects of various growth factors on the metabolic enzymes of sulfoglycolipids were investigated by using a human renal cell carcinoma cell line, SMKT-R3. Among the growth factors tested, transforming growth factor alpha (TGF-alpha) and epidermal growth factor (EGF) were found to increase the sulfotransferase activity markedly (about 300%), but did not change that of arylsulfatase A, which hydrolyzes sulfoglycolipids. The augmented effects of TGF-alpha was abolished by cycloheximide. Since TGF-alpha is known to bind to the same receptor as EGF, SMKT-R3 cells were investigated for the EGF receptor by affinity cross-linking with 125I-EGF. A radiolabeled protein with a molecular mass of 175 kDa corresponding to the ligand-receptor complex was immunoprecipitated with a monoclonal anti-EGF receptor antibody. When production of the growth factors was examined immunochemically, the cells were found to secrete TGF-alpha at a low level and retain it in a membrane-bound form, whereas EGF was not detected. These observations suggest that the sulfotransferase activities are regulated through the autocrine, paracrine, and/or juxtacrine modes of intercellular stimulation by TGF-alpha in human renal cancer cells.

Carcinoma, Renal Cell↗
PubMed1993

[Intravascular ultrasound imaging as adjunct to vascular interventions: preliminary experience in patients with atherosclerotic disease].

Catheter-based intravascular ultrasound (IVUS) imaging is new, evolving technique in which a high-frequency transducer is attached to the tip of a catheter. In this study, we evaluated the usefulness of catheter-based IVUS in 11 patients with atherosclerotic disease as an adjunct to PTA or atherectomy. A 30-MHz ultrasound catheter was inserted through a 6 F sheath to obtain real-time and cross-sectional images. The IVUS images demonstrated a three-layered appearance of muscular arteries, intimal thickening and calcification. IVUS was performed in 11 patients undergoing percutaneous transluminal angioplasty (7 patients) or atherectomy (4 patients). The presence of dissection between the media and atheroma was observed after balloon angioplasty, while IVUS imaging demonstrated a smooth wall after atherectomy. There was a good correlation between IVUS and angiography in the quantitative assessment of luminal %diameter stenosis before vascular intervention, but a poor correlation was observed after angioplasty, probably due to the dissections from balloon dilatation that resulted in irregular crescentic pathways with unclear borders to the lumen on angiography. The results of our study illustrate the potential utility of IVUS as an adjunct to transluminal vascular intervention.

Aged↗
PubMed1993

Expression, purification and binding to the receptor of human insulin-like growth factor II.

Human insulin-like growth factor II (IGF-II) was expressed as a fused protein with 14 additive amino acids in Escherichia coli with a high yield by an expression system using T7 RNA polymerase. Purification of the expressed protein was simply performed using only differential ultrafiltrations, giving a homogeneous preparation upon polyacrylamide gel electrophoresis and high-performance liquid chromatography. The expressed peptide was reacted with a monoclonal antibody raised against native IGF-II on a blotted membrane. Furthermore, the peptide was bound to IGF-II receptor in solubilized rat fetus membrane, though the affinity was slightly inferior to that of native IGF-II. In addition, fusion IGF-II immobilized on a gel matrix was useful for one-step purification of the IGF-II receptor with a high yield from solubilized rat fetus membranes.

Amino Acid Sequence↗
PubMed1993

Reconstitution of lymphoid tissues under the influence of a subclinical level of graft versus host reaction induced by bone marrow T cells or splenic T cell subsets.

Reconstitution of lymphoid tissues under the influence of subclinical graft versus host reaction (GVHR) has been investigated. Lethally irradiated AKR mice were reconstituted with B10 bone marrow (BM) cells which had been treated with anti-Thy-1 antibody alone without complement (GVHR chimera). Their immunological reconstitution was analyzed and compared with that of AKR recipients which had been reconstituted with B10 BM cells treated with anti-Thy-1 antibody plus complement (control chimera). One hundred percent of both chimeras survived more than 100 days without showing clinical signs of GVHR. However, full donor chimerism was accomplished at an early stage after reconstitution in the former GVHR chimeras, whereas a substantial number of recipient T cells persisted in control chimeras for the entire observation period. When reconstitution of various lymphoid tissues was compared between control and GVHR chimeras, no difference in the reconstitution of the thymus and spleen was noted. By contrast, the cellularity of peripheral lymph nodes in GVHR chimeras was regularly considerably lower than that of the control chimeras. The apparent insufficiency of lymph node reconstitution appeared to be attributable to the impairment of lymph node structure itself which may be involved in lymphocyte homing. Furthermore, clonal deletion of V beta 6+ T cells which are reactive to recipient (Mls-1a) antigens was abrogated in the GVHR chimeras but was normally induced in the more completely T cell-depleted control chimeras. This abrogation of clonal deletion of V beta 6+ T cells appeared to result from the early disappearance of recipient T cells in these chimeras. Thus, it appeared that donor T cells in the BM that survive anti-Thy-1 treatment in vitro plus subsequent BM transplantation induced a subclinical level GVHR which contributed to the full donor chimerism as well as abrogation of clonal elimination of V beta 6+ donor T cells. Indeed, inoculation of CD8+ T cells along with the transplantation of the T cell-depleted BM cells (anti-Thy-1 plus C-treated cells) from donor mice into the AKR recipients was also shown to induce a similar state in the recipients.

Animals↗
PubMed1993

Epidermal growth factor elevates the activity levels of glycolipid sulfotransferases in renal-cell-carcinoma cells.

Accumulation of sulfoglycolipids associated with markedly elevated levels of glycolipid-sulfotransferase activity was previously demonstrated in human renal-cell-carcinoma cells. To elucidate the regulatory mechanisms of sulfoglycolipid metabolism in renal-cell carcinoma, effects of various growth factors on the sulfotransferase-activity levels were investigated using a human renal-cell-carcinoma cell line, SMKT-R3. Exogenous epidermal growth factor (EGF) significantly increased the activity levels of the sulfotransferases in a dose-dependent manner, but did not change that of arylsulfatase A, which hydrolyzes sulfoglycolipids. Furthermore, metabolic labeling with 35S-sulfate revealed that the addition of EGF to the culture medium of the cells resulted in an increment of sulfoglycolipid synthesis. The expression of the EGF receptor on SMKT-R3 cells was demonstrated by affinity cross-linking with 125I-EGF. These observations suggest that EGF can regulate sulfotransferase-activity levels in renal-cell-carcinoma cells, and function as one of the regulatory factors of sulfoglycolipid synthesis in these carcinoma cells.

Carcinoma, Renal Cell↗
PubMed1993

Involvement of protein kinase C in the regulation of glycolipid sulfotransferase activity levels in renal cell carcinoma cells.

Accumulation of sulfolipids associated with elevated levels of glycolipid sulfotransferase activities has previously been demonstrated in renal cell carcinoma cells. To investigate the role of protein kinase C in the synthesis of sulfolipids, the effects of 12-O-tetradecanoylphorbol-13-acetate and protein kinase C inhibitors on glycolipid sulfotransferase activity levels were examined in a human renal cell carcinoma cell line, SMKT-R3. Continuous treatment of the cells with 12-O-tetradecanoylphorbol-13-acetate caused a dose- and time-dependent reduction of the sulfotransferase activity levels. Similarly, protein kinase C inhibitors, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride and staurosporine, reduced the enzyme activities in a dose-dependent manner. These observations suggest that the glycolipid sulfotransferase activity levels are regulated by protein kinase C in SMKT-R3 cells. Furthermore, long-term 12-O-tetradecanoylphorbol-13-acetate treatment resulted in a reduction of sulfolipid synthesis and a decrease of the expression of sulfolipids on the cell surface. Taken together, it is suggested that protein kinase C is involved in the synthesis of sulfolipids through the regulation of the glycolipid sulfotransferase activity levels in renal cell carcinoma cells.

Carcinoma, Renal Cell↗
PubMed1993

C-type natriuretic peptide inhibits intimal thickening after vascular injury.

Recently we have found that C-type natriuretic peptide (CNP) inhibits proliferation of cultured rat vascular smooth muscle cells through an elevation of cGMP. We have now tested whether administration of CNP inhibits the development of intimal lesions induced by air-drying injury in rat common carotid arteries in vivo. CNP treatment (1 microgram/kg/min, i.v. infusion) for either 14 or 5 days resulted in 70% or 60% reduction, respectively, of intimal cross-section area 14 days after injury as compared with control rats. We also found that CNP potently stimulated cGMP production in injured carotid arteries with intimal thickening, but not in intact ones. These results indicate that GC-B, CNP specific receptor/guanylyl cyclase, is expressed at the sites of vascular injury, and that CNP might be efficacious in the prevention of restenosis caused by intimal thickening following coronary angioplasty.

Animals↗
PubMed1993

Functional coupling of the src-family protein tyrosine kinases p59fyn and p53/56lyn with the interleukin 2 receptor: implications for redundancy and pleiotropism in cytokine signal transduction.

The binding of interleukin 2 (IL-2) to the IL-2 receptor (IL-2R) induces a rapid increase in tyrosine phosphorylation of cellular proteins. In a previous study, we have shown that p56lck (lck), a src-family protein tyrosine kinase (src-PTK), physically and functionally associates with the IL-2R beta chain (IL-2R beta). To further investigate a role of src-PTKs in IL-2 signaling, we analyzed a mouse pro-B-cell line, in which lck is not expressed detectably. We observed that in this cell line, IL-2 induces activation of at least two src-PTKs, p59fyn (fyn) and p53/56lyn (lyn). Interestingly, stimulation of this cell line with IL-3 also induces activation of src-PTKs. The activation of fyn or lyn seems to be selective for stimulation with IL-2 or IL-3 since stimulation with IL-6 fails to activate them. Furthermore, we provide evidence for the physical association of fyn with IL-2R beta. Taken together with previous results, our current study suggests that different src-PTKs, each of which is expressed in a cell-type-specific manner, can participate in the IL-2 signal transduction.

Animals↗
PubMed1993

Charged collagen structure mediates the recognition of negatively charged macromolecules by macrophage scavenger receptors.

Macrophage scavenger receptors mediate the recognition of a wide range of negatively charged macromolecules including modified low density lipoproteins (LDL). Truncated bovine receptors lacking residues 330-342, which include the conserved lysine cluster of a collagen-like domain, were unable to degrade modified LDL in spite of their expression on the cell surface. Substitution of lysine 337 into alanine abolished the acetyl-LDL degradation and binding at 37 degrees C, but did not abolish the 4 degrees C binding. In contrast, substitution of more than 2 lysines in this region are needed to abolish the oxidized LDL degradation and 37 degrees C binding. Based on computational modeling of this domain, we propose that a "charged collagen" structure containing a lysine cluster forms a positively charged groove which specifically interacts with negatively charged ligands.

Amino Acid Sequence↗
PubMed1993

Cytosolic free magnesium concentration in human platelets.

Although the magnesium ion (Mg2+) is considered to play an important role in cell activation, information is limited by the lack of suitable methods for measuring cytosolic free Mg2+ concentration ([Mg2+]i). We measured [Mg2+]i in resting and activated human platelets using a new fluorescent Mg(2+)-indicator, mag-fura-2. [Mg2+]i was 0.54 +/- 0.14 mM in resting platelets from 15 healthy volunteers. [Mg2+]i was elevated to 1.33 +/- 0.44 mM and 0.92 +/- 0.37 mM in platelets stimulated with thrombin and collagen, respectively. Increased Mg2+ was considered to be derived chiefly from intracellular Mg2+ mobilization. These results suggest that platelet activation is associated with the increase in [Mg2+]i. The estimation of [Mg2+]i using this method is useful for the investigation of mechanism for various cell activation.

Blood Platelets↗