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T Matsuda

Publications and source records attributed to T Matsuda.

At least 361 records · Page 20Linked to original sources
PubMed1998

Differential effect of alpha-lactalbumin on beta-1,4-galactosyltransferase IV activities.

We isolated a human cDNA clone encoding beta-1,4-galactosyltransferase (beta-1,4-GalT IV) which shares 37% identity with previously characterized mammalian beta-1,4-GalT (beta-1,4-GalT I). By transfection of the full length cDNA into Sf-9 cells and assay of the cell homogenates, higher beta-1,4-GalT activity toward GlcNAc beta-S-pNP was obtained, and its activity was modulated with alpha-lactalbumin, while no lactose synthetase activity was detected in the presence of alpha-lactalbumin. Northern blot analysis using total and poly (A)+ RNA preparations revealed that the expression level of beta-1,4-GalT IV transcript is low and relatively constant while that of beta-1,4-GalT I transcript is dramatically increased in the mouse mammary gland during lactation. These results indicate that beta-1,4-GalT IV can interact with alpha-lactalbumin but has no lactose synthetase activity.

Animals↗
PubMed1998

A significant reduction of macrophages expressing inducible nitric oxide synthase in rat hepatic allografts pretreated with donor-specific blood.

BACKGROUND: A single intravenous injection of donor-specific blood (DST) 7 days before transplantation significantly prolongs survival of hepatic allografts from fully allogeneic ACI(RT1a)-->LEW(RT1(1)) rats. The aim of this study was to investigate the kinetics of nitric oxide synthesis by macrophages in rat hepatic allografts treated with DST. METHODS: We investigated macrophages expressing inducible nitric oxide synthase in animal group I (receiving isografts), group II (hepatic allografts), and group III (hepatic allografts after donor-specific blood). RESULTS: Serum nitrite/nitrate, interferon-gamma, and tumor necrosis factor-alpha concentrations increased significantly in group II for 7 days after transplantation but were significantly much lower in groups I and III. Numbers of macrophages immunostained with an anti-macrophage nitric oxide synthase monoclonal antibody and inducible nitric oxide synthase mRNA levels in liver specimens also were much lower in groups I and III than in group II. In addition, Northern blot analysis demonstrated abundant interleukin-10 mRNA transcripts in the DST-treated hepatic allografts compared to untreated allografts. Double immunostaining revealed anti-macrophage synthase-containing cells, including both ED1+ and ED2+ cells, in liver and spleen as more numerous in group II. CONCLUSIONS: Inducible nitric oxide synthase is suppressed in immunologic unresponsiveness to grafts after donor-specific blood transfusion.

Animals↗
PubMed1998

Development of an enzyme-linked immunosorbent assay-based method for measuring galactosyltransferase activity using a synthetic glycopolymer acceptor substrate.

A lectin-assisted enzyme-linked immunosorbent assay (ELISA)-based method using a synthetic glycopolymer as an acceptor substrate was developed for measuring beta 1,4-galactosyltransferase (GalT) activity. A polyacrylamide derivative having a beta-linked N-acetylglucosamine (GlcNAc beta) moiety on each monomeric unit was synthesized chemically and immobilized on a polystyrene microtiter plate as an acceptor substrate for GalT. After the plate was incubated with bovine GalT, the enzyme reaction product, beta-linked Gal residue on the polyacrylamide-bound GlcNAc residue, was detected by using Ricinus communis agglutinin 1 (RCA1), rabbit anti-RCA1 antibody, and a peroxidase-labeled anti-rabbit IgG. The lowest GalT concentration detectable by this method was about 0.5 mU/ml, which is comparable to those by the previously reported ELISA-based assays. The unique property of the glycopolymer, PAP(GlcNAc beta), of binding noncovalently but tightly to the polystyrene microtiter plate allowed the use of this acceptor substrate for the GalT activity measurement even in the presence of 1% Triton CF-54 and X-100. Our system was successfully applied to assess GalT activity in milk of various mammals.

Acetylglucosamine↗
PubMed1998

Prolonged survival of rat hepatic allografts treated with a pretransplant donor-specific blood transfusion is associated with reduced cytokine-induced neutrophil chemoattractant expression.

BACKGROUND: One intravenous injection of freshly heparinized donor blood 7 days before transplantation significantly prolongs hepatic allograft survival from ACI (RT1a) to LEW [RT1(1)] rats. The aim of this study was to investigate hepatic allograft expression of neutrophil chemoattractant and tumor necrosis factor in immunologic unresponsiveness. METHODS AND RESULTS: Cytokine-induced neutrophil chemoattractant levels in untreated hepatic allografts were significantly higher than in allografts treated with donor-specific transfusion. Additionally, more neutrophils infiltrated untreated than transfusion-treated hepatic allografts. The number of chemoattractant-positive cells was significantly lower in donor-specific transfused allografts than in untreated hepatic allografts. The number of ED1+ mononuclear cells infiltrating portal areas of untreated allografts increased over time and expressed abundant cytokine-induced neutrophil chemoattractant mRNA during acute rejection. This correlated with significantly higher levels of chemoattractant mRNA in untreated allograft livers on postoperative day 5 as compared with transfusion-treated allografts. Serum concentrations of tumor necrosis factor-alpha in untreated hepatic allograft recipients increased over time and peaked on day 7, while those in transfused allografts were maintained at lower levels. Moreover, in vitro chemoattractant production by peritoneal macrophages responded in a dose-dependent manner to tumor necrosis factor-alpha. CONCLUSION: Donor-specific transfusion treatment decreases tumor necrosis factor-alpha and chemoattractant expression as well as neutrophil accumulation in hepatic allografts.

Animals↗
PubMed1998

Nitric oxide donor decreases neutrophil adhesion in both lung and peritoneum during peritonitis.

BACKGROUND: As nitric oxide (NO) is an antiadhesive molecule, exogenous NO may modulate neutrophil adhesion in organs. This study was designed to examine the effects of the NO donor SNAP (S-nitroso-acetyl penicillamine) on neutrophil adhesion at the inflammatory site and in remote organs, in peritonitis using a fluorescent microscopic method. MATERIALS AND METHODS: In experiment 1, rats (n = 12) were given saline or 10 micrograms/kg of SNAP intravenously followed by continuous infusion of saline, or of 2, 20, or 200 micrograms/kg/h SNAP until sacrifice. Ten minutes after injection of saline or SNAP, 10(7) Escherichia coli were injected into the peritoneal cavity. Five hours after challenge, 10(6) fluorescein-labeled neutrophils were infused. Peritoneal samples, lungs, liver, and kidney were harvested for counting of labeled neutrophils under epifluorescent microscopy. In experiment 2, rats (n = 25) were treated with saline or 10 micrograms/kg of SNAP intravenously and infused with saline or 20 micrograms/kg/h SNAP; E. coli was injected as in experiment 1. Before or 5 h after challenge, hemodynamic data were obtained. Then, labeled neutrophils were infused for counting of neutrophil numbers in organs. Arterial blood gas data and the circulating neutrophil number were also determined. RESULTS: Experiment 1. Twenty and 200 micrograms/kg/h SNAP infusions tended to reduce labeled neutrophil numbers in lungs, while all three SNAP doses decreased the peritoneal labeled neutrophil numbers. RESULTS: Experiment 2. Five hours after bacterial injection, SNAP infusion simultaneously decreased both pulmonary and peritoneal labeled neutrophil numbers. SNAP had no effect on hemodynamic and blood gas data, or on circulating neutrophil numbers. CONCLUSION: NO donors may be useful for preventing neutrophil-associated lung injury, but should be used with caution in light of the possible adverse effects on host defense in the peritoneal cavity.

Animals↗
PubMed1998

Reduced UV-induced mutations in human osteosarcoma cells stably expressing transfected wild-type p53 cDNA.

We constructed the plasmid which can express human wild-type p53 cDNA and introduced it into the human osteosarcoma cell line SAOS-2 that lacks the chromosomal p53 gene. A cell clone stably expressing p53 protein was isolated and UV sensitivity and UV-induced mutation frequencies of the clone were examined. The UV sensitivity of the clone was slightly higher and UV-induced hprt mutation frequencies of the clone were markedly lower than those of parental SAOS-2 cells. The capability to repair UV-induced DNA damage assessed by the amount of unscheduled DNA synthesis or DNA single strand breaks as well as cell cycle progression after UV irradiation were not different between the clone and SAOS-2 cells. These results indicate that wild-type p53 protein would be involved in the human DNA damage-processing pathway other than the genome-overall excision repair.

Cell Survival↗
PubMed1998

High intra-abdominal pressure increases plasma catecholamine concentrations during pneumoperitoneum for laparoscopic procedures.

BACKGROUND: Laparoscopic procedures are associated with several complications, such as hemodynamic, respiratory, and endocrine complications. In our previous clinical study, plasma epinephrine and norepinephrine concentrations remained unchanged after the insertion of a Veress needle, but increased significantly immediately after insufflation with carbon dioxide into the peritoneum. The mechanisms for this increase are unknown. OBJECTIVE: To investigate whether gas insufflation during pneumoperitoneum affects plasma catecholamine concentrations during laparoscopic procedures. DESIGN: Experimental study in pigs. MAIN OUTCOME MEASURES: The plasma concentrations of epinephrine and norepinephrine were measured in the pigs before and after pneumoperitoneum. The mean arterial pressure, heart rate, cardiac output, and arterial blood gas levels were measured, and the systemic vascular resistance was calculated. INTERVENTION: Air, nitrous oxide, or carbon dioxide were insufflated in turn into the peritoneal cavity of supine pigs. Thereafter, carbon dioxide was insufflated into the peritoneal cavity while the pig was in the left lateral decubitus position, and then in the right lateral decubitus position. Measures were performed before pneumoperitoneum and at the intra-abdominal pressures of 10 mm Hg and 20 mm Hg. One hour of resting time was allowed between each procedure. RESULTS: As compared with baseline values, the plasma concentrations of epinephrine and norepinephrine remained unchanged at 10 mm Hg but increased significantly at 20 mm Hg regardless of the gas used for the pneumoperitoneum (P<.05). The type of gas and differences in the position of the animals had no effect on the plasma epinephrine and norepinephrine concentrations. CONCLUSIONS: Excessive intra-abdominal pressure, but not the type of gas or body position, increases plasma catecholamine concentrations during the insufflation of gas into the abdominal cavity. Therefore, excessive insufflation of the pneumoperitoneum should be avoided.

Abdomen↗
PubMed1998

Monocyte chemoattractant protein-1 enhances expression of intercellular adhesion molecule-1 following ischemia-reperfusion of the liver in rats.

Intercellular adhesion molecule-1 (ICAM-1) is important in neutrophil-dependent injury. We investigated the effects of monocyte chemoattractant protein-1 (MCP-1) produced by Kupffer cells on ICAM-1 expression after ischemia-reperfusion in rat liver by occluding the portal vein for 30 minutes. Serum concentrations of MCP-1 increased persistently. By Northern analysis, MCP-1 mRNA increased early and persisted. Kupffer cells harvested 6 hours after reperfusion also expressed this transcript. The transcript and protein also were produced by Kupffer cells from naive controls in response to reactive oxygen species. ICAM-1 mRNA transcripts increased, peaked 3 hours after reperfusion, and decreased gradually thereafter. The level of ICAM-1 mRNA transcripts in the WK-5 rat endothelial cell line were markedly enhanced by MCP-1. These results suggest that MCP-1 released by Kupffer cells early after ischemia-reperfusion modulates neutrophil-dependent tissue injury via ICAM-1.

Animals↗
PubMed1998

Infiltrating CD45RC- T cells are associated with immunologic unresponsiveness induced by donor class I major histocompatibility complex antigens in rats.

It has previously been shown that a single intravenous injection of freshly heparinized donor-specific blood transfusion (DST) before transplantation significantly prolongs the survival of fully allogeneic ACI (RT1a)-to-LEW(RT1(1)) rat hepatic allografts. Additionally, we have shown that pretreatment of LEW rats with PVG.r1 blood, which shares only the RT1.A major histocompatibility complex (MHC) region with ACI, significantly prolongs the survival of ACI hepatic allografts. In this study, we report the cellular identity of hepatic allograft leukocyte infiltrates following transplantation. Fluorescence-activated cell sorting (FACS) analysis revealed that CD4+ T cells infiltrating liver allografts could be divided into two subsets, CD45RC- CD4+ and CD45RC+ CD4+ T cells, and that the ratio of CD45RC- CD4+/CD45RC+ CD4+ T cells was significantly higher in hepatic allografts of recipients pretreated with DST or PVG.r1 blood as compared to untreated allografts. Further, CD8+ T cells that accumulated in the liver grafts could be similarly divided into two subsets, and the ratio of CD45RC- CD8+/CD45RC+ CD8+ T cells was also significantly higher in hepatic allografts of recipients pretreated with DST or PVG.r1 blood. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis revealed that CD45RC- CD4+ T cells harvested from hepatic allografts pretreated with PVG.r1 blood expressed interleukin-4 (IL-4) and interleukin-10 (IL-10), but not interleukin-2 (IL-2) or interferon-gamma (IFN-gamma). In contrast, CD45RC- CD8+ T cells from hepatic allografts pretreated with PVG.r1 blood expressed IL-4, IL-10, and IFN-lambda, but not IL-2. These results indicate that the CD45RC leukocyte common antigen could be used to differentiate CD4+ and CD8+ T cells following pretreatment with DST or PVG.r1 blood. Persistent infiltration of CD45RC- CD4+ and CD45RC- CD8+ T cells, capable of secreting Th2-type cytokines may prevent allograft rejection by causing immunologic unresponsiveness.

Animals↗
PubMed1998

Xanthine oxidase inhibition attenuates kupffer cell production of neutrophil chemoattractant following ischemia-reperfusion in rat liver.

We investigated the effects of the xanthine oxidase inhibitor, BOF-4272, on the production of cytokine-induced neutrophil chemoattractant (CINC) following reperfusion injury in rat liver. Ischemia was induced for 30 minutes by portal vein occlusion. Animals were pretreated with intravenous injection of BOF-4272 (1 mg/kg) or heparin (50 U/kg) 5 minutes before vascular clamp. Both BOF-4272 and heparin limited increases in the chemoattractant compared with nonpretreated rats. Pretreatment with BOF-4272 plus heparin resulted in an additive effect. Most cells immunostained for chemoattractant were macrophages in sinusoids. In vitro chemoattractant production by Kupffer cells isolated from animals pretreated with heparin or BOF-4272 was significantly lower than by Kupffer cells from nonpretreated animals. Expression of transcripts in liver for chemoattractant peaked 3 hours after reperfusion in nonpretreated animals, while pretreatment with heparin or BOF-4272 significantly decreased chemoattractant mRNA levels. In vitro chemoattractant transcription and production could be induced in naive Kupffer cells by hypoxanthine and xanthine oxidase, but BOF-4272 prevented these increases. We conclude that Kupffer cells release chemoattractant in response to oxygen radicals reducible by xanthine oxidase inhibition.

Animals↗
PubMed1998

Scintigraphic evaluation of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. Comparison between scintigraphy, radiography and outcome in 34 patients.

Scintigrams and radiographs of 36 femoral heads in 34 patients before and after Sugioka's transtrochanteric rotational osteotomy for osteonecrosis of the femoral head were investigated prospectively. Patients were followed for more than 3 years after the operation. The patterns of early scintigrams made within 3 months of the operation were classified into four categories. All 4 patients with a large cold area evidenced collapse within 1 year despite good recovery of the weight-bearing surfaces immediately after operation on conventional radiograms. Twenty-two hips with no cold area in the femoral head did not demonstrate collapse. Femoral head collapse after rotational osteotomy can be predicted by early postoperative bone scintigraphy.

Adolescent↗
PubMed1998

Significance of magnetic resonance image and blood manganese measurement for the assessment of brain manganese during total parenteral nutrition in rats.

In this study, we report on the influence of trace elements (TE) on signal intensities of nuclear magnetic resonance images (MRI), both in vivo and in vitro. Optimal parameters for the assessment of Mn concentration in the brain of rats on total parenteral nutrition were established. For the in vitro study, Mn and trace element solutions, one containing Zn, Cu, Fe, and I (TE-4) and another containing the above elements plus Mn (TE-5), were diluted with physiological saline or with rat brain homogenate and used to measure signal intensities in MRI. Concentration-dependent signal hyperintensity was observed in both cases in the Mn and the TE-5 solutions, but no effect was observed with the TE-4 solution. The signal increase was greater for brain tissue homogenates. In the in vivo study, the experimental animals were maintained under total parenteral nutrition (TPN) with a standard clinical dose of TE-5 and/or with 10-fold the clinical dose of TE-4 and TE-5 for 1 wk. Only rats that were receiving the increased TE-5 dose showed signal hyperintensity on MRI. Positive correlations were observed among the signal hyperintensity, the blood Mn concentrations, and that of the rat brain. Our results suggest that Mn in TE preparations may be the cause of signal hyperintensity on MRI in a concentration-dependent fashion, and that MRI and measurement of blood Mn may be used to estimate Mn accumulation in brain tissue.

Animals↗
PubMed1998

Cough receptor sensitivity to capsaicin and tartaric acid in patients with Mycoplasma pneumonia.

There has been no detailed study of cough sensitivity during acute lower respiratory infection. The aim of this study was to clarify cough sensitivity in Mycoplasma pneumonia, which is a well known acute lower respiratory infection with persistent nonproductive cough. We examined cough sensitivity to inhaled capsaicin and tartaric acid in both the acute and the convalescent phases of Mycoplasma pneumonia, cell differentials in bronchoalveolar lavage fluid, and pathologic findings of transbronchoscopic bronchial biopsy specimens. Although dry cough was observed in all patients during Mycoplasma pneumonia, cough sensitivity in the acute phase [capsaicin: 19.8 (GSEM, 0.214) microM, tartaric acid: 0.26 (GSEM, 0.356) M] were not enhanced compared with those in both control subjects [capsaicin: 27.9 (GSEM, 1.24) microM, tartaric acid: 0.316 (GSEM, 0.079) M] and patients in the convalescent phase [capsaicin: 15.7 (GSEM, 0.219) microM, tartaric acid: 0.50 (GSEM, 0.326) M] when all symptoms including cough had disappeared. The percentage of lymphocytes and neutrophils in bronchoalveolar lavage fluid BALF was significantly greater than in the control subjects, and lymphocyte-dominant bronchitis was observed in biopsied specimens. We conclude that cough threshold to inhaled capsaicin or tartaric acid was not enhanced during acute Mycoplasma pneumonia with lymphocyte-predominant bronchitis. This is the first report examining cough sensitivity in patients with acute lower respiratory infection with pneumonia.

Adult↗
PubMed1998

Pathological significance of elevated soluble CD14 production in rheumatoid arthritis: in the presence of soluble CD14, lipopolysaccharides at low concentrations activate RA synovial fibroblasts.

In order to establish what contributes to elevated levels of soluble CD14 (sCD14) in rheumatoid arthritis (RA) plasma, levels of sCD14 were compared in RA-paired plasma and synovial fluids and, further, in the culture supernatants of monocyte-rich fractions from patients with RA and healthy donors, and macrophage-rich fractions from RA synovial tissues. The results showed elevated sCD14 in RA synovial fluid in 9 of 16 paired samples and in RA macrophage-rich fractions, suggesting that elevated sCD14 in RA plasma might be due to the sCD14 production by RA synovial macrophages. From the molecular analysis of elevated sCD14, the proteolytic cleavage of membranous CD14 (mCD14) was important in accelerated sCD14 production. Lipopolysaccharides (LPS) at low concentrations and sCD14 increased the ICAM-1 expression on RA synovial fibroblasts. This result implies that in vivo RA synovial fibroblasts may be sensitive to LPS in the presence of sCD14 and LPS-binding protein (LBP).

Adult↗
PubMed1998

Complications and management of microwave coagulation therapy for primary and metastatic liver tumors.

Microwave coagulation therapy (MCT) has been widely used, both percutaneously and directly, as effective minimal invasive therapy for liver tumors. To facilitate the use of MCT, we describe the complications we have encountered, and their possible management and prophylaxis. MCT was performed for 42 patients with hepatocellular carcinoma (HCC) and for 29 with metastatic liver tumors, following which complications developed in 14.2% and 20.6% of the HCC and metastatic groups, respectively. The complications included abscess, biloma, bleeding, hepatic failure, and dissemination of cancer cells. In the HCC group, the mean value of tumor size and the clinical stage of patients with complications were significantly larger (P = 0.006) and higher (P = 0.032), respectively, than those of patients without complications. The incidence of complications increased significantly when the tumor size was more than 4cm (P = 0.008). Abscesses and bleeding were successfully treated using percutaneous drainage and interventional angiography, respectively, but as the other serious complications were not able to be treated effectively once induced, prophylaxis is important to facilitate MCT. Transcatheter cooling of the intrahepatic bile duct during MCT and the administration of an anticancer agent into the abdominal cavity are recommended to prevent biloma and dissemination, respectively. MCT is indicated for tumors less than 4 cm in diameter to reduce the risk of complications. The prophylaxis and treatment of these complications enhance the safety of MCT.

Aged↗