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Biomedical subjects

K Matsui

Publications and source records attributed to K Matsui.

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

Lipoteichoic acid from Staphylococcus aureus induces Th2-prone dermatitis in mice sensitized percutaneously with an allergen.

BACKGROUND: We found previously that lipoteichoic acid (LTA) from Staphylococcus aureus has the ability to induce Th2 cytokine production by peripheral blood mononuclear cells (PBMC) from patients with atopic dermatitis (AD). However, it is not known whether LTA can induce a Th2-dominant cytokine response in the skin of AD patients. OBJECTIVE: The purpose of this study was to determine the effects of LTA in mice sensitized percutaneously with a house dust mite antigen (MA) through barrier-disrupted skin, as an experimental animal model of AD. METHODS: Mice were sensitized with MA by a single topical application to barrier-disrupted abdominal skin. Seven days after the sensitization, the mice were challenged on the dorsal skin by LTA to elicit localized skin inflammation. The cytokine response in the dorsal skin was investigated by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistological analysis. The infiltration of inflammatory cells in the skin was also observed by histological staining. RESULTS: Injection of LTA into the dorsal skin of MA-sensitized mice, which show a Th2-dominant cytokine response against the homologous antigen, increased the expression of mRNA for IFN-gamma, IL-4 and IL-5, but not IL-2. Immunohistological analysis demonstrated that levels of IFN-gamma, IL-4 and IL-5 transcripts corresponded with those of protein synthesis. In addition, the dorsal skin of MA-sensitized mice challenged with LTA showed significantly increased numbers of neutrophils, eosinophils, mononuclear cells and mast cells compared with control mice challenged with LTA. CONCLUSION: These results suggest that LTA has the ability to induce localized Th2-prone dermatitis in an allergen-independent manner in the skin of AD patients and may explain the role of colonization with S. aureus in AD patients.

Allergens↗
PubMed2002

Effect of an Na+/H+ exchange inhibitor, SM-20550, on ischemic preconditioning in rabbits.

The effects of SM-20550 [N-(aminoiminomethyl)-1,4-dimethyl-1H-indole-2-carboxamide methanesulfonic acid], an Na+/H+ exchange inhibitor, on ischemic preconditioning (IPC) were studied in a rabbit model of myocardial ischemia and reperfusion injury. Anesthetized rabbits underwent occlusion of the coronary artery (30 min) followed by reperfusion (5 h). In SM-20550-treated animals, SM-20550 was intravenously administered at 0.03 mg/kg or 0.1 mg/kg before ischemia (30 min). Treatment with SM-20550 at 0.03 mg/kg had a nonsignificant tendency to reduce infarct size (18%). In contrast, 0.1 mg/kg of SM-20550 significantly reduced infarct size by 62%. In animals with IPC, the condition was induced by 2 or 5 min of ischemia and 10 min of reperfusion prior to sustained ischemia (30 min). Although 5 min of IPC significantly reduced infarct size by 72%, 2 min of IPC reduced infarct size by only 27%, which was not significant. The combination of 5 min of IPC and 0.1 mg/kg of SM-20550 significantly reduced infarct size by 78%. This reduction in infarct size was similar to that produced by 0.1 mg/kg SM-20550 or 5 min of IPC alone. Moreover, the combination of 2 min of IPC and 0.03 mg/kg of SM-20550 significantly reduced infarct size by 64%, although neither 0.03 mg/kg SM-20550 nor 2 min of IPC alone reduced infarct size significantly. These results indicate that an Na+/H+ exchange inhibitor SM-20550, does not antagonize the cardioprotective effect of IPC. SM-20550 and IPC appeared to act synergistically to exert a combined cardioprotective effect.

Amidines↗
PubMed2001

Lembehyne A, a spongean polyacetylene, induces neuronal differentiation in neuroblastoma cell.

Lembehyne A (LB-A), a spongean polyacetylene, induced neuronal cell differentiation in a neuroblastoma cell line, Neuro 2A. The LB-A treatment of Neuro 2A cells predominantly resulted in a morphological change with bipolar neurites. The acetylcholinesterase activity of Neuro 2A was also increased by the treatment of LB-A. Furthermore, the cell cycle of Neuro 2A cells was found to be specifically blocked at the G1 phase by LB-A. The structure-activity relationship study using the LB-A analogues revealed the importance of the terminal 1-yn-3-ol and unsaturated long-chain alkyl moieties for the neuronal differentiation activity of LB-A.

Acetylcholinesterase↗
PubMed2001

Effects of maitake (Grifola frondosa) D-Fraction on the carcinoma angiogenesis.

We have reported that D-Fraction extracted from maitake (Grifola frondosa), activates immune competent cells, and indicates anti-tumor activities. The D-Fraction was observed to induce angiogenesis in vivo and to enhance the proliferation capability and migration capability of human vascular endothelial cell in vitro. The D-Fraction also increased plasma vascular endothelial growth factor (VEGF) concentration significantly. Also VEGF and TNF-alpha production by the activated peritoneal macrophages were enhanced. These results suggest that the anti-tumor activity of the D-Fraction is not only associated with the activation of the immuno-competent cells but also possibly related to the carcinoma angiogenesis induction.

Animals↗
PubMed2001

Phase II study of S-1, a novel oral fluorouracil, in advanced non-small-cell lung cancer.

The purpose of this study was to evaluate the efficacy and safety of a novel oral anticancer fluoropyrimidine derivative, S-1, in patients receiving initial chemotherapy for unresectable, advanced non-small-cell lung cancer (NSCLC). Between June 1996 and July 1998, 62 patients with NSCLC who had not received previous chemotherapy for advanced disease were enrolled in this study. 59 patients (22 stage IIIB and 37 stage IV) were eligible for the evaluation of efficacy and safety. S-1 was administered orally, twice daily, after meals. 3 dosages of S-1 were prescribed according to body surface area (BSA) so that they would be approximately equivalent to 80 mg m(-2)day(-1): BSA < 1.25 m(2), 40 mg b.i.d.; BSA> or =1.25 but <1.5 m(2); 50 mg b.i.d., and BSA> or =1.5 m(2): 60 mg b.i.d. One cycle consisted of consecutive administration of S-1 for 28 days followed by a 2-week rest period, and cycles were repeated up to 4 times. The partial response (PR) rate of the eligible patients was 22.0% (13/59); (95% confidence interval: 12.3-34.7%). A PR was observed in 22.7% (5/22) of the stage IIIB patients and 21.6% (8/37) of the stage IV patients. The median response duration was 3.4 months (1.1-13.7 months or longer). Grade 4 neutropenia was observed in one of the 59 patients (1.7%). The grade 3 or 4 toxicities consisted of decreased haemoglobin level in 1.7% of patients (1/59), neutropenia in 6.8% (4/59), thrombocytopenia in 1.7% (1/59), anorexia in 10.2% (6/59), diarrhoea in 8.5% (5/59), stomatitis in 1.7% (1/59), and malaise in 6.8% (4/59), and their incidences were relatively low. There were no irreversible, severe or unexpected toxicities. The median survival time (MST) of all patients was 10.2 months (95% confidence interval: 7.7-14.5 months), and the one-year survival rate was 41.1%. The MST of the stage IIIB patients was 7.9 months, and that of the stage IV patients was 11.1 months. The one-year survival rates of the stage IIIB and IV patients were 30.7% and 47.4%, respectively. S-1 was considered to be an active single agent against NSCLC. Further study of S-1 with other active agents is warranted.

Administration, Oral↗
PubMed2001

Reversible airflow obstruction, proliferation of abnormal smooth muscle cells, and impairment of gas exchange as predictors of outcome in lymphangioleiomyomatosis.

Lymphangioleiomyomatosis (LAM) is a rare disease, occurring in women, characterized by cystic degeneration of the lungs, abdominal tumors, and proliferation of abnormal smooth muscle cells. Lung function abnormalities consist of impairment of the diffusion capacity (DL(CO)) and airflow obstruction. The objective of this study was to correlate the functional impairment with histologic measures of disease severity to identify predictors of disease outcome. Lung function of 143 patients and lung biopsies of 74 of these patients were reviewed for evidence of airway disease and scoring of disease severity. A positive response to bronchodilators was associated with more severe airflow obstruction, a predominantly solid pattern of LAM lesions in the lung biopsy, and greater rate of decline in expiratory flow. Airway inflammation, present in 61% of the lung specimens, was not associated with reversible airway obstruction and did not correlate with the severity of airflow obstruction. DL(CO) correlated best with the LAM histologic score (LHS), a demonstrated predictor of outcome. We conclude that reversible airway obstruction is found in LAM patients with accelerated loss of lung function and a predominantly solid pattern of LAM lesions. Impairment of DL(CO) correlates with LHS, a predictor of survival and time to lung transplantation.

Adult↗
PubMed2001

Involvement of NADH/NADPH oxidase in human platelet ROS production.

Platelets play an important role in atherosclerotic and thromboembolic vascular diseases. It has been reported that reactive oxygen species (ROS) could modify platelet function, and platelets themselves have the ability to produce ROS. However, the enzymatic sources of ROS in platelets have not been fully determined. The NADH/NADPH oxidase system was originally identified as the major source of ROS in phagocytes. Recently, it has become evident that this oxidase is functionally expressed not only in phagocytes but also in various cell types. The present study was undertaken to test the hypothesis that NADH/NADPH oxidase might be expressed in human platelets. Lucigenin-enhanced chemiluminescence (L-CL) and electron spin resonance (ESR) method demonstrated that human platelets obtained from healthy volunteers released ROS, and the released ROS were increased by stimulation with 12-O-tetradecanoylphorbol-13-acetate (TPA) or calcium ionophore. Homogenates of human platelets, as well as MEG01 cells, megakaryocytic cell line, had the enzymatic activity to produce superoxide in NADH/NADPH-dependent manners. This enzymatic activity was suppressed by diphenylene iodonium (DPI), an inhibitor of NADH/NADPH oxidase. Western blot analysis demonstrated that platelets and MEG01 cells expressed p22(phox) and p67(phox) proteins, components of NADH/NADPH oxidase. Thus, human platelets have the enzymatic activity of p22(phox)-based NADH/NADPH oxidase, and this oxidase is likely one of the important sources of ROS in platelets.

Blood Platelets↗
PubMed2001

The homolytic and heterolytic fatty acid hydroperoxide lyase-like activities of hematin.

Pentenols and pentene dimers are biosynthetized in plants by homolytic fatty acid hydroperoxide lyase (HPL) or HPL-like enzymes. It has been found that these compounds can modify the flavor of olive oil. Reactions between hematin and 13-hydroperoxyoctadecatrienoic acid resulted in the formation of the same compounds via a free radical reaction in which an alkoxyl radical derived from linolenic acid hydroperoxide undergoes a beta-scission. (Z)-3-Hexenal has also been detected as a minor product of the reaction. It is bioconversed from the same substrate in plants by heterolytic HPL. Thanks to the redox cycle of its central iron, hematin has both homolytic and heterolytic HPL-like activities.

Aldehyde-Lyases↗
PubMed2001

Fas ligand-induced caspase-1-dependent accumulation of interleukin-18 in mice with acute graft-versus-host disease.

Acute graft-versus-host disease (aGVHD), the fatal side effects of bone marrow transplantation, was shown to be accompanied by elevation of serum levels of interleukin 18 (IL-18). In this study, the mechanism underlying the accumulation of IL-18 in aGVHD in mice was investigated. Lethally irradiated recipients having transplantation with H-2 disparate donor splenocytes demonstrated aGVHD and contained markedly elevated serum levels of IL-18. In contrast, recipients having transplantation with gld/gld spleen cells, which lack functional Fas ligand (FasL), contained only normal ranges of IL-18, indicating FasL-mediated IL-18 release in aGVHD. The wild-type hosts engrafted with caspase-1-deficient cells revealed marked increases of IL-18 similar to those engrafted with wild-type cells, whereas caspase-1-deficient recipients engrafted with wild-type cells showed only a slight elevation of serum IL-18, indicating that IL-18 elevation is derived from host cells in a caspase-1-dependent manner. These results suggest FasL-mediated caspase-1-dependent IL-18 secretion in aGVHD in mice.

Acute Disease↗
PubMed2001

Differentiation in chronic myelogenous leukemia cell K562 by spongean sesterterpene.

Scalarane-type sesterterpenes, PHC-1-PHC-7, which have been isolated from a marine sponge, increased hemoglobin production in human chronic myelogenous leukemia cell line K562 at the concentration of 0.1-5 microg/ml. PHC-1, the major constituent, induced the expression of glycophorin A and the enucleation for K562 cells. These sesterterpenes were found to induce erythroid differentiation in K562 cells. In addition, PHC-1 induced G1 arrest of the cell cycle of K562 cells.

Animals↗
PubMed2001

Selective down-regulation of high-affinity IgE receptor (FcepsilonRI) alpha-chain messenger RNA among transcriptome in cord blood-derived versus adult peripheral blood-derived cultured human mast cells.

Substantial numbers of human mast cells (MCs) were generated from umbilical cord blood (CB) and from adult peripheral blood (PB). A single CB progenitor produced 15 436 MCs, whereas a single PB progenitor produced 807 MCs on average. However, PB-derived MCs were far more active than CB-derived MCs in terms of high-affinity IgE receptor (FcepsilonRI)-mediated reactions. One million sensitized PB-derived MCs released 3.6 microg histamine, 215 pg IL-5, and 14 ng granulocyte macrophage-colony-stimulating factor (GM-CSF), whereas 10(6) sensitized CB-derived MCs released only 0.8 microg histamine, 31 pg IL-5, and 0.58 ng GM-CSF on anti-IgE challenge. However, ionophore A23 187 released similar levels of histamine from the 2 MC types. PB-derived MCs highly expressed surface FcepsilonRI alpha chain, and CB-derived MCs almost lacked it in the absence of IgE. PB-derived MCs expressed approximately 5 times higher levels of messenger RNA (mRNA) for FcepsilonRI alpha chain than CB-derived MCs, but mRNAs for beta and gamma chains of the receptors were equally expressed. Among the approximately 5600 kinds of full-length human genes examined by using the high-density oligonucleotide probe-array system, FcepsilonRIalpha was ranked the fifth most increased transcript in PB-derived MCs. The 4 other increased transcripts were unrelated to MC function. These results suggest that IgE-mediated reactions may be restricted during early infancy through the selective inhibition of FcepsilonRIalpha transcription, which is probably committed at progenitor stages and is, at least in part, cytokine-insensitive.

Adult↗
PubMed2001

Survivin expression in tumor cell nuclei is predictive of a favorable prognosis in gastric cancer patients.

One hundred and thirty three gastric cancer cases were investigated immunohistochemically to clarify the biological role of survivin in gastric cancer cells using a commercially available anti-survivin antibody (SURV11A). Five gastric cancer cell lines were employed to assess localization of survivin by reverse-transcription-polymerase chain reaction (RT-PCR) Southern blotting, Western blotting and immunofluorescence, signals being found in both nucleus and cytoplasm. Survivin nuclear staining of gastric cancer cells was evident in 109 of 133 cases (82.0%) and associated with a favorable prognosis, being an independent prognosticator on multivariate analysis. Survivin nuclear positivity also correlated with younger age and lower incidence of vessel cancer invasion. In contrast, survivin cytoplasmic positivity was noted in 117 cases (88.0%) and did not correlate with any factor of progression or prognosis. The results indicate that survivin is present in the majority of gastric cancer cells but a nuclear localization may play an important physiological role in hindering tumor progression.

Adult↗
PubMed2001

Identification of a novel plant-specific kinesin-like protein that is highly expressed in interphase tobacco BY-2 cells.

Through reverse transcription-polymerase chain reaction and Northern blot analysis, we identified TBK5, a novel plant-specific kinesin-like protein (KLP) that is highly expressed in interphase tobacco BY-2 cells. TBK5 mRNA was present at a high level throughout the growth cycle, even in cells that had entered the stationary phase, where cell proliferation had ceased. However, transcripts for five other tobacco KLPs that we have identified were preferentially expressed in mitotic cells, and either not or only slightly accumulated in cells that had entered the stationary phase. Thus, TBK5 appears to be a KLP whose cellular function most closely relates to the cortical array of microtubules that plays a key role in plant cell morphogenesis. The predicted structure of TBK5 is characterized by a central motor domain that is phylogenetically distant from those of other reported KLPs, coiled-coil domains located on both sides of the motor domain, and a basic C-terminal domain. In addition, TBK5 has a putative neck domain which is closely related to the neck domain of KLPs with C-terminal motor domains, previously shown to control the direction of KLP movement towards the minus ends. Antibodies against truncated TBK5 recognized a polypeptide with a molecular mass of 74 kDa in cytoplasmic extracts of interphase cells, and this polypeptide cosedimented with microtubules assembled in the cytoplasmic extracts. The 74 kDa polypeptide corresponding to TBK5 dissociated from microtubules with high concentrations of NaCl but was not dissociated by MgATP. We hypothesize that TBK5 functions in the regulation of the arrangement of cortical microtubules.

Algal Proteins↗
PubMed2001

Inhibitory effect of SM-20550, an Na+/H+ exchange inhibitor, on accumulation of leukocytes in ischemia and reperfusion.

The effect of an Na+/H+ exchange inhibitor, SM-20550, on the adhesion, emigration and accumulation of leukocytes was studied in ischemia and reperfusion injury models using rat mesenteric venules or rabbit heart. Anesthetized rats underwent occlusion of the superior mesenteric artery (20 min) followed by reperfusion (60 min). After ischemia and reperfusion, the numbers of adherent and emigrated leukocytes increased significantly. Bolus intravenous administration of SM-20550 reduced the numbers of adherent and emigrated leukocytes in a dose-dependent manner, with statistical significance at dosages >0.1 mg/kg. Anesthetized rabbits underwent occlusion of the coronary artery (30 min) followed by reperfusion (5 h). Intravenous administration of SM-20550 before ischemia significantly reduced the neutrophil accumulation in the area-at-risk by 46% and reduced the infarct size by 38%. These results suggest that the inhibitory effect of SM-20550 on the neutrophil accumulation could be one of the mechanisms by which this drug limits the severity of infarctions.

Amidines↗