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T Matsunaga

Publications and source records attributed to T Matsunaga.

At least 37 records · Page 2Linked to original sources
PubMed2002

Management of blunt hepatic injury in children: usefulness of emergency transcatheter arterial embolization.

We reviewed our experience to determine the usefulness of emergency transcatheter arterial embolization (TAE) for severe blunt hepatic injury (BHI) in children. Between 1978 and 2000, 21 children with BHI (14 boys and 7 girls, ranging in age from 2 to 14 years) were managed according to our protocol. The patients who were hemodynamically stable, and had no other associated injury requiring laparotomy, regardless of the hepatic injury grade, were managed nonsurgically. Emergency angiography and TAE performed after a CT scan revealed extravasation of the contrast medium. Of the 21 patients, 3 underwent emergency laparotomy; 2 due to hemodynamic instability despite fluid resuscitation (1 died), and the 3rd patient because of associated injury. The other 18 patients (86%) were initially managed nonsurgically; however, 2 underwent delayed laparotomy because of complications (1 each of suspected delayed hepatic hemorrhage and liver abscess). Nonsurgical management was completed in the remaining 16 (89%) with no morbidity and mortality. Two of the 16 returned to a hemodynamically stable condition with fluid resuscitation, but were compromised with persistent hepatic hemorrhage, and were successfully treated with emergency TAE. We propose that emergency TAE should be considered as an initial treatment for severe BHI in children.

Adolescent↗
PubMed2002

Successful treatment of advanced peripheral T-cell lymphoma with an angiocentric growth pattern complicated with hemophagocytic syndrome by high-dose chemotherapy and autologous peripheral blood stem cell transplantation.

Peripheral T-cell lymphomas (PTCL) account for about 10% of all lymphomas in Western countries, respond poorly to therapy, and have short survival with no sustained remission. Furthermore, the complication of hemophagocytic syndrome (HPS) sometimes makes the prognosis of this disease extremely worse. We report here a case of PTCL with an angiocentric growth pattern complicated with HPS successfully treated by high-dose chemotherapy and autologous peripheral blood stem cell transplantation. Our case suggests this approach is an excellent candidate for the treatment of this disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Effects of cerivastatin on vascularized allogenic bone transplantation in rats treated with cyclosporine A.

The aim of the present study was to investigate the effects of oral cerivastatin (0.1 mg/kg/day) on vascularized allogenic transplanted bone that is treated with cyclosporine A (CsA) (10 mg/kg/day) and on vascularized isogenic transplanted bone that is not treated with CsA. Allogenic transplantation was performed on 12-week-old male DA rats with the major histocompatibility antigen (MHC) RT1a (as the donor) and age-matched male Lewis rats with MHC RT1l (as the recipient), and isogenic transplantation was performed on 12-week-old male Lewis rats. After transplantations, 20 rats (10 rats in each transplantation) were randomized into four groups to receive the following treatment for 16 weeks: (1) CsA plus cerivastatin vehicle or (2) CsA plus cerivastatin in the allogenic transplanted rats, and (3) CsA vehicle plus cerivastatin vehicle or (4) CsA vehicle plus cerivastatin in the isogenic transplanted rats. Bone biochemical markers, mineral density, and strength were measured at the end of the study period. Serum levels of osteocalcin (OC) and parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD) level were higher in the allogenic transplanted rats than in the isogenic transplanted rats. In the allogenic transplanted rats, the cerivastatin treatment decreased urinary DPD levels, but not serum OC nor PTH levels. Furthermore, the cerivastatin treatment improved bone mineral density of the allogenic transplanted bones and bone strength of the allogenic reconstructed bones. In contrast, no effect of the cerivastatin treatment was observed in the isogenic transplanted rats. These results suggest that the cerivastatin treatment improves CsA-induced high-turnover osteopenia mainly through the inhibition of bone resorption.

Amino Acids↗
PubMed2002

A case of true malignant histiocytosis: identification of histiocytic origin with use of immunohistochemical and immunocytogenetic methods.

We report here an autopsy case of true malignant histiocytosis. The patient was a 67-year-old woman who exhibited fever, wasting, hepatosplenomegaly, and progressive pancytopenia. The bone marrow aspiration disclosed hemophagocytosing cells, which resembled histiocytes. The molecular analysis did not show the clonal gene rearrangement of T-cell receptor or immunoglobulin heavy chain. Although the patient had been started on methylprednisolone pulse therapy and chemotherapy with etoposide, she died from cerebral hemorrhage. The autopsy specimens of spleen and liver showed extensive infiltration of atypical cells, for which histiocytic origin was identified with an immunohistochemical method using monoclonal antibodies against CD11c, CD68, macrophage colony-stimulating factor (M-CSF), M-CSF receptor, lysozyme, antitrypsin and alpha1-antichymotrypsin. Recent investigations have disclosed that in most cases diagnosed as malignant histiocytosis, hemophagocytosis was reactive and not evoked by histiocytic malignancy. True malignant histiocytosis, for which histiocytic origin is confirmed, is extremely rare.

Aged↗
PubMed2002

Abnormal distributions of callosal commissural and corticothalamic neurons in the cerebral neocortex of Shaking Rat Kawasaki.

Shaking Rat Kawasaki (SRK) is an autosomal recessive mutant rat recognized by unstable gait and tremor and by early death around the time of weaning. We previously reported that corticospinal tract neurons are malpositioned in the motor cortex of the SRK rat [Ikeda and Terashima (1997) J. Comp. Neurol. 383, 370-380]. In the present study, we examined the distribution pattern of callosal commissural (CC) and corticothalamic (CT) neurons of SRK and normal rats with the injection of horseradish peroxidase (HRP) into the contralateral hemisphere or wheat germ agglutinin-conjugated HRP into the ventral lateral thalamic nucleus. The intracortical distribution pattern of retrogradely labeled CC and CT neurons in the motor cortex of SRK rat was abnormal: CC neurons were more deeply situated and CT neurons were more superficially situated in the SRK cortex than the corresponding components in the normal cortex. Most of labeled CC and CT neurons had abnormal dendritic configurations. Statistical analysis revealed that the difference of the mean intracortical position of CC and CT neurons of the SRK was significantly different from the normal counterparts (Student's t-test, P<0.01). Taken together with previous findings, our data demonstrate that the abnormal cytoarchitecture of SRK cortex resembles the reeler cortex.

Agenesis of Corpus Callosum↗
PubMed2002

Analysis of gene expression during maturation of immature dendritic cells derived from peripheral blood monocytes.

Dendritic cells (DCs) are the most important antigen-presenting cells. Many recent studies have compared the function of immature DCs (iDCs) and mature DCs (mDCs), but there have been few reports of the molecular changes that occur in DCs during maturation. Here, we report on differential gene expression in iDCs generated from peripheral blood monocytes compared with mDCs. Gene expression was evaluated using the differential display method after activation of iDCs with a low concentration of lipopolysaccharide (LPS) to induce maturation. Proteasome subunit alpha type 3 (PSMA3), transcription factor EC (TFEC) isoform and BTK region clone 2f10-rpi were transiently upregulated. Tryptophanyl-tRNA synthetase and CD63 antigen were upregulated for at least 24 h. Neuronal apoptosis inhibitory protein (NAIP) and transforming growth factor-beta-induced 68 kDa protein were downregulated. This is the first report of NAIP expression in human DCs. By comparing the expression of NAIP with that of other members of the inhibitor of apoptosis protein (IAP) family and the Bcl-2 family, only NAIP was found to be strongly expressed in iDCs before stimulation by LPS. PSMA3 was also induced in the DCs stimulated with immune complex. These findings might contribute to our understanding of DC maturation and the effectiveness of DC-based vaccines.

Apoptosis↗
PubMed2002

Outcome of hepatoblastoma treated with the JPLT-1 (Japanese Study Group for Pediatric Liver Tumor) Protocol-1: A report from the Japanese Study Group for Pediatric Liver Tumor.

PURPOSE: Hepatoblastoma is the most common malignant liver tumor in childhood. Multicenter studies elucidate the optimal pre- or postoperative chemotherapeutic regimens. This report reviews the results of the Japanese Study Group for Pediatric Liver Tumor Protocol-1 (JPLT-1) and compares its outcomes with published reports of other studies. METHODS: From March 1991 to December 1999, 154 patients with malignant liver tumor including 145 cases of hepatoblastomas were enrolled in the JPLT study. Data from 134 cases were analyzed in this study. JPLT-1 protocol 91A was used for patients with stage I or II hepatoblastoma. The chemotherapy regimen consisted of repeated courses of cisplatin (CDDP), 40 mg/m(2), and tetrahydropyranyl (THP)-Adriamycin, 30 mg/m(2). JPLT-1 protocol 91B was administered to patients with stage IIIA, IIIB, or IV hepatoblastoma. The chemotherapy regimen consisted of repeated courses of CDDP, 80 mg/m(2), and THP-Adriamycin, 30 mg/m(2)/day for 2 days. Courses were repeated every 4 weeks as tolerated. RESULTS: Seven patients died of chemotherapy-related side effects. Six of them died of sepsis caused by leukopenia and 1 case of liver failure. Overall survival rate (3-year/6-year) was 100%/100% for stage I (n = 9), 100%/95.7% for stage II (n = 32), 76.6%/73.8% for stage IIIA (n = 48), 50.3%/50.3% for stage IIIB (n = 25), 64.8%/38.9% for stage IV (n = 20), and 77.8%/73.4% overall. For stage IIIA and B disease, intravenous chemotherapy was better than intraarterial chemotherapy (66.4% v 38.1% for event-free survival and 69.3% v. 57.1% for overall survival). Patients less than 1 year of age had a better prognosis than older patients, but age was not a significant prognostic factor by multivariate analysis. CONCLUSIONS: The overall and event-free survival rates of the JPLT-1 study of hepatoblastoma were comparable with the results of other multicenter studies in Europe and the United States. The event-free survival rate at 3 years for stage IIIB and IV disease was under 50%. New treatment strategies are needed for patients with advanced hepatoblastoma.

Adolescent↗
PubMed2001

Amplified UvrA protein can ameliorate the ultraviolet sensitivity of an Escherichia coli recA mutant.

When a recA strain of Escherichia coli was transformed with the multicopy plasmid pSF11 carrying the uvrA gene of E. coli, its extreme ultraviolet (UV) sensitivity was decreased. The sensitivity of the lexA1 (Ind(-)) strain to UV was also decreased by pSF11. The recA cells expressing Neurospora crassa UV damage endonuclease (UVDE), encoding UV-endonuclease, show UV resistance. On the other hand, only partial amelioration of UV sensitivity of the recA strain was observed in the presence of the plasmid pNP10 carrying the uvrB gene. Host cell reactivation of UV-irradiated lambda phage in recA cells with pSF11 was as efficient as that in wild-type cells. Using an antibody to detect cyclobutane pyrimidine dimers, we found that UV-irradiated recA cells removed dimers from their DNA more rapidly if they carried pSF11 than if they carried a vacant control plasmid. Using anti-UvrA antibody, we observed that the expression level of UvrA protein was about 20-fold higher in the recA strain with pSF11 than in the recA strain without pSF11. Our results were consistent with the idea that constitutive level of UvrA protein in the recA cells results in constitutive levels of active UvrABC nuclease which is not enough to operate full nucleotide excision repair (NER), thus leading to extreme UV sensitivity.

Adenosine Triphosphatases↗
PubMed2001

Adenovirus-mediated transfection of caspase-8 augments anoikis and inhibits peritoneal dissemination of human gastric carcinoma cells.

Caspase-8 is a member of the cysteine protease family that modulates apoptosis induced by a variety of cell death signals and has recently been found to be activated during the process of anoikis, which is a form of apoptosis caused by loss of anchorage in epithelial cells. We previously demonstrated that the inhibition of anoikis promotes peritoneal dissemination of human gastric carcinoma MKN45 cells, which are anchorage dependent. This suggests that augmentation of anoikis may suppress dissemination of carcinoma cells. To determine whether extrinsic overexpression of caspase-8 can augment anoikis in MKN45 cells, we transfected them with the caspase-8 gene using an adenoviral (Adv) vector (Adv-caspase-8). Here we demonstrate that Adv-caspase-8 infection, at 15 multiplicity of infection (MOI), can augment anoikis in MKN45 cells and suppresses MKN45 peritoneal dissemination in SCID mice. The inhibitory effect on peritoneal dissemination resulted in a prolonged survival compared with that in control mice. In contrast, the Adv-caspase-8 (15 MOI) had no distinct effect on cell viability or growth either of attached MKN45 cells or of s.c. tumor growth in SCID mice. Thus, Adv-mediated overexpression of caspase-8 suppressed peritoneal dissemination mainly through augmentation of anoikis. In addition, Adv-caspase-8-mediated augmentation of anoikis was similarly observed in another gastric carcinoma MKN74 cell line. In contrast, Adv-p53 could not augment anoikis in MKN45 cells. These results imply that Adv-mediated gene transfer of caspase-8 can selectively induce apoptosis in detached carcinoma cells and, thus, shows potential as a novel cancer therapy against dissemination of gastric and probably other carcinoma cells originating from epithelial tissues.

Adenocarcinoma↗
PubMed2001

Glycated high-density lipoprotein induces apoptosis of endothelial cells via a mitochondrial dysfunction.

Glycation of plasma proteins may contribute to an excess risk of developing atherosclerosis in patients with diabetes mellitus. Although it is believed that high-density lipoprotein (HDL) is nonenzymatically glycosylated at an increased level in diabetic individuals, little is known about a possible linkage between glycated HDL and endothelium dysfunction in diabetes. This study set out to clarify whether glucose-modified HDL affects the function of endothelial cells by examining the apoptosis of cultured human aortic endothelial cells (HAECs) exposed to a glycated-oxidized HDL (gly-ox-HDL) prepared in vitro. Incubation of HAECs with 100 microg/ml of gly-ox-HDL for 48 h showed apoptotic features, such as cell shrinkage, membrane blebbing, and concentration and fragmentation of the nucleus, and the degree of apoptosis was dose-dependent on the glucose used in the preparation of gly-ox-HDL. Stimulation of HAECs with gly-ox-HDL elicited a marked increase in caspase 3 activity and the expressions of active caspase 3 and caspase 9, whereas concomitant treatment with a caspase 3 inhibitor significantly blocked gly-ox-HDL-induced apoptosis of HAECs. The release of cytochrome c into cytosols markedly increased in HAECs during the treatment with gly-ox-HDL. The increased expressions of Bax and Bad were detected in HAECs incubated for 24 h with gly-ox-HDL, but gly-ox-HDL failed to interfere with the expression of Bcl-2 and Bcl-x. Moreover, in vitro experiments with HDL (gly-HDL) glycated in the presence of 2 mM EDTA and Cu(2+)-oxidized HDL suggested that the apoptotic effect of gly-ox-HDL on endothelial cells might be due to an additional oxidative modification of gly-HDL. Taken altogether, additional oxidation of HDL under hyperglycemic conditions may induce endothelial apoptosis through a mitochondrial dysfunction, following the deterioration of vascular function.

Aorta↗
PubMed2001

A magnetosome-specific GTPase from the magnetic bacterium Magnetospirillum magneticum AMB-1.

Magnetic bacteria produce intracellular vesicles that envelope single domain magnetite crystals. Although many proteins are present in this intracellular vesicle membrane, five are specific to this membrane. A 16-kDa protein, designated Mms16, is the most abundant of the magnetosome-specific proteins, and to establish its function we cloned and sequenced its gene from Magnetospirillum magneticum AMB-1. This was achieved by determination of the N-terminal amino acid sequence of the protein following two dimensional polyacrylamide gel electrophoresis, and sequencing of the gene was performed by gene walking using anchored polymerase chain reaction. Mms16 contains a putative ATP/GTP binding motif (P-loop). Recombinant Mms16 with a hemagglutinin tag, was expressed in Escherichia coli and purified. Recombinant Mms16 protein could bind GTP and showed GTPase activity. GTP was the preferred substrate for Mms16-catalyzed nucleotide triphosphate hydrolysis. These results suggest that a novel protein specifically localized on the magnetic particle membrane, Mms16, is a GTPase. Mms16 protein showed similar characteristics to small GTPases involved in the formation of intracellular vesicles. Furthermore, addition of the GTPase inhibitor AlF(4)- also inhibited magnetic particle synthesis, suggesting that GTPase is required for magnetic particles synthesis.

Amino Acid Sequence↗
PubMed2001

Effects of growth medium composition, iron sources and atmospheric oxygen concentrations on production of luciferase-bacterial magnetic particle complex by a recombinant Magnetospirillum magneticum AMB-1.

Growth conditions for mass production of luciferase-bacterial magnetic particles (BMPs) by a recombinant Magnetospirillum magneticum AMB-1 were investigated in a pH-regulated fed-batch culture system. Enrichment of growth medium with L-cysteine, yeast extract and polypeptone enhanced both bacterial growth and BMP production. The presence of L-cysteine in the medium was useful for induction of cell growth. Strict anaerobic conditions led to a prolonged lag phase and limited the final cell density. Trace oxygen enhanced cell growth with increasing BMP production. As iron sources, ferrous sulfate and ferric gallate dramatically enhanced BMP yield as compared with ferric quinate, an iron chelate conventionally used. The optimized conditions increased cell density to 0.59 +/- 0.03 g cell dry weight/liter and BMP production to 14.8 +/- 0.5 mg dry weight/liter in fed-batch culture for four days.

Journal Article↗
PubMed2001

Preferential degradation of osteoclasts by titanium tetrachloride.

Although titanium alloys are known to be biocompatible with bone tissue after implantation in human beings, the effect of titanium on osteoclasts remains to be studied. We examined the effect of titanium salt on the formation and survival of osteoclasts in cell culture. The addition of 10 microM titanium tetrachloride caused a decrease in the cell number of osteoclast-like cells induced in bone marrow cell cultures taken from mice. The addition of 10 microM titanium tetrachloride caused degradation of the disaggregated osteoclasts taken from neonatal rats and a decrease in bone resorption. Along with the increase in the degradation of osteoclasts, the number of apoptotic cells increased. Titanium tetrachloride dose-dependently decreased the cell number and alkaline phosphatase activity of osteoblastic cell cultures taken from rat calvaria. However, these concentrations were 30-40 times higher than those in the case of osteoclast-like cell formation. These results showed that titanium ions caused a preferential degradation of osteoclasts rather than osteoblasts, most likely by apoptosis.

Alkaline Phosphatase↗
PubMed2001

Fluorescent detection of cyanobacterial DNA using bacterial magnetic particles on a MAG-microarray.

Bacterial magnetic particles (BMPs) were used for the identification of cyanobacterial DNA. Genus-specific oligonucleotide probes for the detection of Anabaena spp., Microcystis spp., Nostoc spp., Oscillatoria spp., and Synechococcus spp. were designed from the variable region of the cyanobacterial 16S rDNA of 148 strains. These oligonucleotide probes were immobilized on BMPs via streptavidin-biotin conjugation and employed for magnetic-capture hybridization against digoxigenin-labeled cyanobacterial 16S rDNA. Bacterial magnetic particles were magnetically concentrated, spotted in 100-microm-size microwell on MAG-microarray, and the fluorescent detection was performed. This work details the development of an automated technique for the magnetic isolation, the concentration of hybridized DNA, and the detection of specific target DNA on MAG-microarray. The entire process of hybridization and detection was automatically performed using a magnetic-separation robot and all five cyanobacterial genera were successfully discriminated.

Base Sequence↗
PubMed2001

Prevention of lethal acute graft-versus-host disease in mice by oral administration of T helper 1 inhibitor, TAK-603.

Acute graft-versus-host diseases (GVHD) is a major cause of morbidity and mortality in patients undergoing allogeneic bone marrow transplantation (BMT). T helper 1 (Th1)-type cytokines such as interferon-gamma or tumor necrosis factor-alpha have been implicated in the pathogenesis of acute GVHD. TAK-603 is a new quinoline derivative, which is now in clinical trials for use as a disease-modifying antirheumatic drug. In preclinical studies, it inhibited delayed-type hypersensitivity, but not Arthus-type reaction, in mice, and selectively suppressed Th1 cytokine production. Thus, the present study was designed to investigate whether the Th1 inhibitor (TAK-603) ameliorates lethal acute GVHD in a mouse model. Administration of TAK-603 into BALB/c mice given 10 Gy total body irradiation followed by transplantation of bone marrow and spleen cells from C57BL/6 mice markedly reduced the mortality in association with minimal signs of GVHD pathology in the liver, intestine, and skin. TAK-603 reduced not only the production of Th1-type cytokines, but also the proportion of Th1 cells in CD4(+) helper T cells in this GVHD mouse model. These results suggest that TAK-603 could be a potent therapeutic agent for acute lethal GVHD.

Acute Disease↗
PubMed2001

Damaged DNA-binding protein DDB stimulates the excision of cyclobutane pyrimidine dimers in vitro in concert with XPA and replication protein A.

Human cells contain a protein that binds to UV-irradiated DNA with high affinity. This protein, damaged DNA-binding protein (DDB), is a heterodimer of two polypeptides, p127 and p48. Recent in vivo studies suggested that DDB is involved in global genome repair of cyclobutane pyrimidine dimers (CPDs), but the mechanism remains unclear. Here, we show that in vitro DDB directly stimulates the excision of CPDs but not (6-4)photoproducts. The excision activity of cell-free extracts from Chinese hamster AA8 cell line that lacks DDB activity was increased 3-4-fold by recombinant DDB heterodimer but not p127 subunit alone. Moreover, the addition of XPA or XPA + replication protein A (RPA), which themselves enhanced excision, also enhanced the excision in the presence of DDB. DDB was found to elevate the binding of XPA to damaged DNA and to make a complex with damaged DNA and XPA or XPA + RPA as judged by both electrophoretic mobility shift assays and DNase I protection assays. These results suggest that DDB assists in the recognition of CPDs by core NER factors, possibly through the efficient recruitment of XPA or XPA.RPA, and thus stimulates the excision reaction of CPDs.

Base Sequence↗
PubMed2001

Expression of alpha-amylase gene in rat liver: liver-specific amylase has a high affinity to glycogen.

The reactivity of rat liver alpha-amylases with maltotriose (G3), maltopentose (G5) and glycogen has been investigated. Liver amylases were found to be glycosylated and to have a molecular mass of 50 kDa by Western blotting using an anti-human salivary amylase antibody. The glycosylated liver amylases were found to be capable of G3- and G5-hydrolysis and of glucose formation, as demonstrated by thin-layer chromatography. When the amylase preparation was exposed to different concentrations of glycogen and run on a cellulose acetate membrane, the mobilities of rat liver amylases significantly decreased with tailing directly from the point of origin. In contrast, rat salivary amylases were not so much. These results indicate that rat liver amylases have a strong affinity to glycogen. We confirmed the expression of liver-specific amylases in rat liver by reverse transcriptional-polymerase chain reaction (RT-PCR); PCR products showed one band of an expected size of 474 bp using primers tested in the present study. A partial nucleotide sequence was then determined. When compared with the gene of mouse liver amylase, the substitution of 26 bases out of 434 bases was elucidated. The present data demonstrate the presence of liver-specific amylases in rats.

Animals↗