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Biomedical subjects

T Matsuda

Publications and source records attributed to T Matsuda.

At least 397 records · Page 22Linked to original sources
PubMed1998

ARF-induced lysosomal lysis in vitro.

Cytosol treated with guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS) disintegrated lysosomes in a dose-dependent manner, as detected as the release of preloaded fluorescein isothiocyanate-dextran. The effect of GTPgammaS was suppressed by GTP or GDP, indicating a role of a GTP binding protein (G-protein) in the lysis [Sai, Y. et al. (1994) Biochem. Biophys. Res. Commun. 198, 869-877]. Gel filtration of cytosol and GTP-ligand blotting showed that a small GTP-binding protein participated in the lysosomal lysis. We partially purified the G-protein from rat liver cytosol and identified it as ARF1. GTPgammaS-stimulated lysis was reconstituted with ARF1 purified from bovine brain cytosol or recombinant ARF1. ARF bound to lysosomal membranes depending upon GTPgammaS in a dose-dependent manner. These results suggest that the transfer of ARF from the cytosol to the lysosomal membrane is necessary for GTPgammaS-stimulated lysis of lysosomes.

ADP-Ribosylation Factor 1↗
PubMed1998

Molecular cloning and characterization of P47, a novel boar sperm-associated zona pellucida-binding protein homologous to a family of mammalian secretory proteins.

P47, a peripherally associated 47-kDa protein of porcine spermatozoa, was identified by affinity chromatography in the fraction of solubilized plasma membrane proteins bound to immobilized porcine zona pellucida glycoproteins. N-terminal and internal amino acid sequences revealed structural similarity between P47 and rat O-acetyl ganglioside synthase, bovine mammary gland protein (MGP)57/53 and mouse milk fat globule protein E8-polypeptides of unknown function secreted by mammary gland epithelial cells in both species. A polyclonal antibody directed against bovine MGP57/53 displayed cross-reactivity with P47. Indirect immunofluorescence analysis located porcine P47 on the acrosomal cap of testicular sperm and on sperm recovered along different sections of the ductus epididymidis, as well as on swim-up and in vitro-capacitated sperm. Porcine P47 was demonstrated on sperm bound to the zona pellucida of a homologous oocyte. Western blot analysis identified P47 (or MGP57/53) homologous proteins in porcine and human milk. Like the sperm-associated protein, porcine milk P47 possesses affinity for isolated, biotinylated sow oocyte zona pellucida glycoproteins. Reverse transcription-polymerase chain reaction was used to isolate P47 homologous cDNAs from porcine testis and mammary gland tissues as well as from bovine, mouse, and human testis. P47 proteins deduced from these cDNA sequences showed 60-100% amino acid sequence identity. These proteins display a mosaic structure organized into two N-terminal, tandemly arranged epidermal growth factor (EGF)-like domains followed by a region with similarity to C1 and C2 domains found in blood clotting factors V and VII. The second EGF-like domain contains an arginine-glycine-aspartic acid sequence, a motif often found in integrin receptor ligands. P47-like proteins are not expressed solely in testicular and mammary gland tissues. Northern blot analysis showed that P47 mRNA is transcribed in several porcine and bovine tissues. These data indicate a potential role for boar sperm-associated P47 in membrane remodeling and/or as a zona pellucida binding protein.

Amino Acid Sequence↗
PubMed1998

Necrotizing bronchial aspergillosis as a cause of hemoptysis in sarcoidosis.

The case history is presented of a patient with recurrent massive hemoptysis caused by necrotizing bronchial aspergillosis associated with sarcoidosis. The involved segments (right IX and X) were resected for treatment of the life-threatening hemoptysis. Histologic examination of the resected specimen confirmed the diagnosis. Necrotizing bronchial aspergillosis is a rare variant form of invasive pulmonary aspergillosis and has not been described previously as a cause of hemoptysis in sarcoidosis.

Aspergillosis↗
PubMed1998

The effects of the lateral position on cardiopulmonary function during laparoscopic urological surgery.

UNLABELLED: Laparoscopic urological surgery is usually performed transperitoneally with retroperitoneal insufflation of carbon dioxide (CO2) in the lateral position. We studied whether a difference in the side of lateral position affected hemodynamic and pulmonary functions during pneumoperitoneum. Fifteen patients (eight in the right and seven in the left lateral position) undergoing elective laparoscopic urological surgery were studied under general anesthesia. Hemodynamic variables and blood gas data were recorded. Before insufflation, mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), central venous pressure (CVP), and pulmonary capillary wedge pressure (PCWP) in the right lateral position were higher than those in the left lateral position. Pneumoperitoneum increased MAP, MPAP, CVP, PCWP, and cardiac index but decreased systemic vascular resistance in the right lateral position. Similar changes occurred during pneumoperitoneum in the left lateral position, but the changes were less than those in the right lateral position. The respiratory index (PaO2/PAO2), intrapulmonary shunt, and SpO2 did not change during pneumoperitoneum in either lateral position. Changing the side of the lateral position affected hemodynamic function but did not affect pulmonary oxygenation during pneumoperitoneum. IMPLICATIONS: The right and left lateral positions produced different hemodynamic changes during laparoscopic urological surgery. The increases in preload and cardiac index and the decrease in systemic vascular resistance were greater in the right than in the left lateral position. Respiratory changes were not affected differently between the right and left lateral positions.

Anesthesia, General↗
PubMed1998

Effects of growth hormone and insulin-like growth factor I on opsonin receptor expression on local and systemic phagocytes in a lethal peritonitis model.

OBJECTIVE: To investigate the effects of pretreatment with growth hormone (GH) and insulin-like growth factor I (IGF-I) on phagocyte exudation and bacterial clearance, focusing on CD11b and CD32/CD16 expression on local and systemic phagocytes, in a lethal peritonitis model. DESIGN: Prospective randomized experimental study. SETTING: Research laboratory in a university hospital. SUBJECTS: Balb/c mice (n = 21). INTERVENTIONS: Mice were challenged intraperitoneally with 1 x 10(8) Escherichia coli, after 6 days of pretreatment with saline (control), GH (4.8 mg/kg/day), or IGF-I (24 mg/kg/day). Samples were harvested at 4 hrs after the challenge. MEASUREMENTS AND MAIN RESULTS: Viable bacterial counts in peritoneal lavage fluid (PLF) and blood were determined. Peritoneal exudative cells and peripheral blood leukocytes were counted and analyzed for receptor expressions by flow cytometry. GH reduced viable bacterial counts in PLF, as compared with the saline control. GH (three-fold) and IGF-I (two-fold) increased the number of peritoneal exudative neutrophils (PENs), as compared with the saline control. The number of PENs showed an inverse correlation with PLF viable bacterial counts. By contrast, there were no differences in peripheral blood neutrophil (PN) counts among the three groups, nor was there a correlation between PN and PEN counts. CD11b expression was greater on PENs than on PNs in all three groups. CD11b expression on PNs did not differ among the three groups. However, GH increased CD11b expression on PENs, as compared with saline and IGF-I, and this expression showed a positive correlation with PEN numbers and an inverse correlation with PLF viable bacterial counts. CD11b expression on peritoneal macrophages and peripheral blood monocytes did not differ among the three groups. There were no differences in phagocyte CD32/CD16 expression among the three groups. CONCLUSIONS: GH pretreatment enhanced CD11b expression on PENs, but not PNs, possibly in association with enhanced neutrophil recruitment, phagocytosis, and bacterial elimination by PENs, without activation of PNs. GH prophylaxis may be useful for reducing the frequency rate and severity of septic complications, via modulation of CD11b expression on local and systemic neutrophils.

Animals↗
PubMed1998

Temperature-sensitive effects of potassium channel openers on isolated guinea pig myocardium and aorta.

The effects of K+ channel openers, NIP-121, cromakalim, and pinacidil, on isolated myocardium and aorta were investigated at two different temperatures, 23 degrees C and 37 degrees C. In right ventricular myocardium, NIP-121 shortened the action-potential duration with little influence on other action-potential parameters at 37 degrees C, but not at 23 degrees C. In whole-cell clamped ventricular myocytes, NIP-121 induced a glibenclamide-sensitive outward current at 37 degrees C but not at 23 degrees C. No difference in tissue adenosine triphosphate (ATP) concentration was detected between ventricular myocardia incubated at 37 degrees C and at 23 degrees C. In aortic preparations precontracted with norepinephrine, NIP-121, cromakalim, and pinacidil produced endothelium-independent relaxation at 37 degrees C, which was antagonized by glibenclamide. The vasorelaxant effects were greatly reduced at 23 degrees C. Thus we demonstrated that the effects of K+ channel openers on the myocardium and vascular smooth muscle are temperature sensitive.

Action Potentials↗
PubMed1998

Immunosuppressants decrease neutrophil chemoattractant and attenuate ischemia/reperfusion injury of the liver in rats.

BACKGROUND: Neutrophils may play an important role in the development of liver ischemia/reperfusion injury. We investigated the effects of the immunosuppressants azathioprine (AZA), cyclosporine A (CsA), tacrolimus (FK506), and rapamycin (RPM) on the expression of cytokine-induced neutrophil chemoattractant (CINC) after ischemia/reperfusion of the liver. METHODS: Liver ischemia was induced in male Wistar rats by occluding the portal vein with a microvascular clip for 30 minutes. Rats received two intramuscular injections of AZA (4 mg/kg), CsA (5 mg/kg), FK506 (0.5 mg/kg), or RPM (0.5 mg/kg) 3 and 24 hours before ischemia/reperfusion of the liver. RESULTS: Serum CINC concentrations in untreated animals increased, peaked 6 hours after reperfusion, and thereafter decreased gradually. Pretreatment with AZA, CsA, FK506, and RPM, however, inhibited the increase in serum CINC concentrations after reperfusion. CINC mRNA in liver tissue increased and peaked 3 hours after reperfusion, but was significantly lower in animals treated with AZA, CsA, FK506, and RPM. In vitro CINC production by Kupffer cells harvested from animals treated with AZA, CsA, FK506, or RPM 3 hours after reperfusion was also significantly lower than that observed in untreated animals. Both myeloperoxidase activity and the number of neutrophils accumulating in the liver 24 hours after reperfusion in animals treated with AZA, CsA, FK506, and RPM were significantly lower than in untreated animals. This correlated with lower serum aspartate transaminase, alanine transaminase, and lactate dehydrogenase levels in animals treated with AZA, CsA, FK506, and RPM 24 hours after reperfusion. CONCLUSION: The immunosuppressants AZA, CsA, FK506, and RPM reduce neutrophil accumulation and attenuate ischemia/reperfusion injury of the liver.

Animals↗
PubMed1998

Growth hormone and insulin-like growth factor I augment bactericidal capacity of human polymorphonuclear neutrophils.

Effects of growth hormone (GH) and insulin-like growth factor (IGF)-I on bactericidal capacity of human polymorphonuclear neutrophils (PMNs) were investigated. Venous blood was collected from healthy volunteers. In Experiment 1, PMNs were isolated, incubated with GH or IGF-I, and cocultured with Escherichia coli. E. coli-killing capacity, viability, and CD11b and CD16 expressions of PMNs were then assessed. Both GH and IGF-I enhanced E. coli killing by PMNs. GH preserved PMN viability during E. coli killing, whereas IGF-I enhanced PMN CD11b expression before coculture with E. coli. In Experiment 2, whole blood was washed and incubated with GH or IGF-I. PMNs in washed whole blood were then analyzed for phorbol myristate acetate (PMA)-stimulated CD11b, CD35, and CD16 expressions and production of reactive oxygen intermediates (ROI), as well as phagocytosis with/without anti-CD11b antibody. IGF-I enhanced PMN expressions of CD11b and CD35, but not CD16, stimulated with PMA. Both hormones enhanced phagocytosis, which was abrogated by anti-CD11b antibody, and intracellular ROI production by PMNs. These results indicate that both GH and IGF-I augment human PMN bactericidal capacity, via increased phagocytosis and intracellular ROI production. Preservation of PMN viability by GH and enhanced complement receptor expression by IGF-I may also be associated with augmented PMN bactericidal capacity. Although PMN activation has potentially harmful aspects, these results encourage additional studies to confirm the clinical relevance of exogenous GH or IGF-I for the prevention or management of septic complications in perioperative or critically ill patients especially with low circulating GH and/or IGF-I levels.

Cell Survival↗
PubMed1998

Effect of an inhibitor of glucosylceramide synthesis on cultured human keratinocytes.

Glucosylceramide (GlcCer) is a major glycosphingolipid component of epidermis, which is thought to be related to the barrier function of skin permeability. However, the role of glycosphingolipids in keratinocyte growth and differentiation has not been fully clarified. It has been reported that D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), an inhibitor of GlcCer synthase (EC 2.4.1.80), depletes cells of glycosphingolipids. This inhibitor has been used as a tool for elucidating their functions. In the present study, the effect of PDMP on cultured normal human keratinocytes was investigated. The cells were treated with various concentrations of PDMP. Forty-eight hours later cell growth, thymidine incorporation, and lipid content were studied. The cell growth and the incorporation of thymidine into cells were inhibited by PDMP in a dose dependent manner. The synthesis of GlcCer was strongly inhibited by PDMP treatment, whereas no significant changes in ceramide level were observed. We concluded that GlcCer in epidermis may play an important role in regulating epidermal growth and suggested that PDMP may be beneficial for treating proliferative skin disorders in the future.

Adult↗
PubMed1998

The molecular mechanism of apoptosis induced by xenogeneic cytotoxicity.

In order to clarify the role of natural killer (NK) cells in delayed xenograft rejection (DXR) of discordant xenotransplantation, we used in vitro xenogeneic combination of human NK cells and pig kidney target cells (PK15), and investigated the mechanism of xenogeneic cytotoxicity caused by human NK cells. In the presence of decomplemented human serum or human IgG, freshly isolated human peripheral blood lymphocytes (PBLs) caused both membrane (51Cr release) and DNA (3H release) damage on PK15. In contrast, only membrane damage was detected in the presence of normal human serum. To clarify the participation of perforin/granzymescell mediated cytotoxicity (P/G-CMC), when EGTA or concanamycin B (CMB) was added to the cytotoxicity assays, both cytotoxicities were completely inhibited by these drugs in a dose-dependent manner. In terms of the involvement of Fas/FasL-based cytotoxicity (F-CMC), while the cytotoxicity assays were performed in the presence of antagonistic anti-human FasL mAb, this antibody was not able to block the cytotoxicity. From these results, it is concluded that xenogeneic cytotoxicity is due to NK cell dependent ADCC (antibody-dependent cell-mediated cytotoxicity), and their effector mechanism can cause apoptosis on target cells via P/G-CMC.

Animals↗
PubMed1998

Airway cough sensitivity to inhaled capsaicin and bronchial responsiveness to methacholine in asthmatic and bronchitic subjects.

The objective of this study was to evaluate the effect of chronic airway inflammation on airway cough sensitivity and non-specific bronchial responsiveness, and the relationship between them. The capsaicin cough threshold, defined as the lowest concentration of capsaicin causing five or more coughs, and non-specific bronchial responsiveness, defined as the methacholine concentration causing a 20% fall in forced expiratory volume in 1 s (FEV1) (PC20-FEV1), were measured in 18 asthmatic, 13 bronchitic (sinobronchial syndrome) and 28 healthy non-atopic subjects. All subjects were non-smoking men. The geometric mean values (mumol) of the cough threshold were 18.9 (GSEM 1.29), 8.69 (GSEM 1.29) and 27.6 (GSEM 1.31) in asthmatic, bronchitic and normal subjects, respectively. The value in bronchitic subjects was significantly lower (P << 0.02) than that in normal subjects. The geometric mean value of PC20-FEV1 in asthmatic subjects (0.48 mg/ml (GSEM 1.38)) was significantly lower than that in bronchitic subjects (18.5 mg/ml (GSEM 1.75)) (P << 0.001). There was no correlation between cough threshold and PC20-FEV1 values (correlation coefficient (r) = 0.155). These results indicate that cough sensitivity is potentiated by chronic airway inflammation in bronchitis but not in asthma, and suggest that cough sensitivity and bronchial responsiveness may be independently potentiated by different mechanisms resulting from chronic airway inflammation.

Administration, Inhalation↗
PubMed1998

Renal cell carcinoma of extraordinarily large size: a case report.

One of our patients was a 66-year-old woman with a T2 renal cell carcinoma weighing 3900 g. Two years after radical nephrectomy the woman was alive and well. A survey of Japanese medical literature revealed that patients with renal cell carcinomas weighing more than 2000 g have an unexpectedly favorable prognosis with a 5-year survival rate of 76.9%.

Aged↗
PubMed1998

Short-term and long-term effects of low-density lipoprotein (LDL) apheresis on restenosis after percutaneous transluminal coronary angioplasty (PTCA): is lowering Lp(a) by LDL apheresis effective on restenosis after PTCA?

It has been reported that serum lipoprotein(a) (Lp[a]) levels in patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA) were significantly higher than in patients without restenosis. In this study, we evaluated the preventive effect of LDL apheresis on restenosis after PTCA in patients with hypercholesterolemia. For 10 patients who had shown a serum cholesterol level of more than 220 mg/dl despite treatment with antihypercholesterolemic drugs, LDL apheresis was conducted every 2 weeks after a successful PTCA until restenosis could be checked. In 4 patients, LDL apheresis was conducted for 2 years. LDL apheresis significantly reduced serum cholesterol from 248 +/- 22 mg/dl to 135 +/- 26 mg/dl and Lp(a) from 42 +/- 34 mg/dl to 21 +/- 16 mg/dl. The average degree of stenosis in the 11 lesions undergoing PTCA was 92 +/- 6% before PTCA, 35 +/- 10% immediately after PTCA, and 38 +/- 19% at 3 to 4 months after PTCA. Restenosis was observed in only 1 lesion. In 4 patients who received LDL apheresis for 2 years, restenosis did not occur in any of the 4 lesions treated. We concluded that LDL apheresis was an efficacious therapy to prevent restenosis after PTCA in patients with hypercholesterolemia.

Adult↗
PubMed1998

Seasonal chronic cough with sputum eosinophilia caused by Trichosporon cutaneum (Trichosporon asahii).

The case of a 46-year-old man with a chronic cough with sputum eosinophilia (atopic cough) caused by Trichosporon cutaneum serotype II (Trichosporon asahii) is reported. The diagnosis was made with the inhalation challenge test with T. asahii antigen. He was admitted for the diagnosis and treatment of a severe nonproductive cough in the summer season. Although his sputum contained 13% eosinophils of nucleated cells, he did not have bronchial hyperresponsiveness to methacholine or a heightened bronchomotor tone. Bronchodilator therapy was not effective for his cough. His symptoms worsened on returning home, suggesting the existence of some etiologic agent in his house. A high titer of serum anti-Trichosporon antibody was detected and antigen provocation test with the Trichosporon extract was positive: the development of a cough 6 h later and a decrease in the cough threshold to inhaled capsaicin 48 h later (7.85 microM from 31.3 microM prechallenge). This is the first report on a chronic cough with sputum eosinophilia induced by T. cutaneum (T. asahii).

Chronic Disease↗
PubMed1998

Bronchoprotective effect of an intrabronchial administration of cilostazol powder and a nebulized PDE1 and PDE4 inhibitor KF19514 in guinea pigs.

BACKGROUND: Both oral and intravenous inhibitors of cyclic nucleotide phosphodiesterase (PDE) 3 and PDE4 have been shown to have bronchodilator and/or pulmonary antiallergic effects but their adverse effects limit the clinical use. The purpose of the present study was to assess the bronchoprotective effect of intrabronchial administration of a selective PDE3 inhibitor, 6-[4-(1-cyclohexyl-1H-tetrazol-5-yl)butoxy]-3,4-dihydro-2(1H)-quin olinone (cilostazol), in dry power form which is proposed to be desirable rather than propellant-driven metered-dose inhalers. METHODS: Effect of an intrabronchial administration of cilostazol powder on aerosolized histamine- and antigen-induced leukotriene-mediated bronchoconstriction were examined in anesthetized and artificially ventilated guinea pigs, in comparison with the effects of ultrasonically nebulized 5-phenyl-3-(3-pyridyl)methyl-3H-imidazo[4,5-c] [1,8] naphthyridin-4(5H)-one (KF19514), a selective PDE1/4 inhibitor. RESULTS: Cilostazol powder and KF19514 solution inhibited histamine- and antigen-induced bronchoconstriction in a dose-dependent manner. When assessing the resulting ED50 values, the activity of cilostazol powder against antigen-induced broncho-constriction was weaker than its antagonism of histamine-induced bronchoconstriction (60.4 vs. 7.0 microg), while those of KF19514 were the opposite (0.40 vs. 2.81 microg/ml). CONCLUSION: These results suggest that intrabronchially administered cilostazol powder has a bronchodilator effect, and ensure that PDE4 inhibitors have an antiallergic activity in addition to their bronchodilator effect.

3',5'-Cyclic-AMP Phosphodiesterases↗