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1.
Int J Oral Maxillofac Surg ; 50(11): 1413-1421, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33663900

ABSTRACT

The purpose of this study was to investigate the prognostic value of prognostic nutritional index (PNI) in oral squamous cell carcinoma (OSCC) patients and to undertake a comparative evaluation of the prognostic value of comparing PNI, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) in terms of prognostic utility. A retrospective study was conducted involving 203 consecutive patients with OSCC who were treated with radical surgery with curative intent. The PNI and systemic inflammatory response were developed, and their prognostic utility was evaluated. Kaplan-Meier curve analysis and log-rank testing showed that PNI (P< 0.001), NLR (P=0.011), PLR (P=0.013), and LMR (P=0.014) were significantly associated with overall survival. Multivariate analysis identified PNI as an independent prognostic factor for OSCC patients (P=0.029). In time-dependent receiver operating characteristic curve analysis, PNI was continuously superior to that of NLR, PLR, and LMR. In conclusion, this study suggested that PNI offered an independent prognostic biomarker in OSCC patients undergoing radical surgery. However, this study was small and retrospective, thus further investigations are needed to clarify the utility of PNI for tailor-made treatments in clinical settings.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Carcinoma, Squamous Cell/surgery , Humans , Mouth Neoplasms/surgery , Neutrophils , Nutrition Assessment , Prognosis , Retrospective Studies , Squamous Cell Carcinoma of Head and Neck
2.
Intern Med ; 40(9): 931-5, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11579959

ABSTRACT

A 45-year-old male was admitted because of chest pain, lumbago, and bilateral ankle pain. Examination disclosed hypophosphatemic osteomalacia, acquired Fanconi syndrome, and abnormalities in distal nephron such as distal renal tubular acidosis and renal diabetes insipidus. Further exploration revealed IgA kappa multiple myeloma excreting urinary Bence Jones protein (kappa-light chain). Renal biopsy revealed thick basement membranes and elec-tron-dense crystals in proximal tubular epithelial cells. Immunofluorescent studies revealed deposition of kappa-light chain in renal tubular epithelial cells that caused the renal tubular damage. Although the osteomalacia was relieved by medical treatment, the urinary Bence Jones protein and the renal tubular defects were not improved by the chemotherapy for the myeloma. The patient died of exacerbation of multiple myeloma at 50 years of age.


Subject(s)
Immunoglobulin A , Immunoglobulin kappa-Chains , Kidney Neoplasms/diagnosis , Kidney Neoplasms/metabolism , Kidney Tubules, Distal/pathology , Kidney Tubules, Proximal/pathology , Kidney/metabolism , Multiple Myeloma/diagnosis , Multiple Myeloma/metabolism , Biopsy , Fatal Outcome , Humans , Kidney/pathology , Kidney Neoplasms/complications , Kidney Neoplasms/pathology , Male , Middle Aged , Multiple Myeloma/complications , Multiple Myeloma/pathology , Osteomalacia/etiology , Time Factors
3.
J Cell Biol ; 154(4): 829-40, 2001 Aug 20.
Article in English | MEDLINE | ID: mdl-11502760

ABSTRACT

Recent studies indicate that insulin stimulation of glucose transporter (GLUT)4 translocation requires at least two distinct insulin receptor-mediated signals: one leading to the activation of phosphatidylinositol 3 (PI-3) kinase and the other to the activation of the small GTP binding protein TC10. We now demonstrate that TC10 is processed through the secretory membrane trafficking system and localizes to caveolin-enriched lipid raft microdomains. Although insulin activated the wild-type TC10 protein and a TC10/H-Ras chimera that were targeted to lipid raft microdomains, it was unable to activate a TC10/K-Ras chimera that was directed to the nonlipid raft domains. Similarly, only the lipid raft-localized TC10/ H-Ras chimera inhibited GLUT4 translocation, whereas the TC10/K-Ras chimera showed no significant inhibitory activity. Furthermore, disruption of lipid raft microdomains by expression of a dominant-interfering caveolin 3 mutant (Cav3/DGV) inhibited the insulin stimulation of GLUT4 translocation and TC10 lipid raft localization and activation without affecting PI-3 kinase signaling. These data demonstrate that the insulin stimulation of GLUT4 translocation in adipocytes requires the spatial separation and distinct compartmentalization of the PI-3 kinase and TC10 signaling pathways.


Subject(s)
Insulin/metabolism , Membrane Microdomains/metabolism , Monosaccharide Transport Proteins/metabolism , Muscle Proteins , rho GTP-Binding Proteins/metabolism , Adipocytes/cytology , Amino Acid Sequence , Animals , Caveolae , Caveolin 1 , Caveolins/genetics , Caveolins/isolation & purification , Cells, Cultured , Glucose Transporter Type 4 , Mice , Molecular Sequence Data , Mutation , Protein Transport , Recombinant Fusion Proteins/metabolism , Signal Transduction , ras Proteins/genetics , rho GTP-Binding Proteins/genetics
4.
J Am Coll Cardiol ; 38(1): 232-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11451280

ABSTRACT

OBJECTIVES: The aim of this study was to examine the effects of essential hypertension on cardiac autonomic function in type 2 diabetic patients. BACKGROUND: Hypertension is common in type 2 diabetic patients and is associated with a high mortality. However, the combined effects of type 2 diabetes and essential hypertension on cardiac autonomic function have not been fully elucidated. METHODS: Thirty-three patients with type 2 diabetes were assigned to a hypertensive diabetic group (n = 15; age: 56 +/- 8 years, mean +/- SD) or an age-matched normotensive diabetic group (n = 18, 56 +/- 6 years). Cardiac autonomic function was assessed by baroreflex sensitivity (BRS), heart rate variability (HRV), plasma norepinephrine concentration and cardiac 123I-metaiodobenzylguanidine (MIBG) scintigraphic findings. RESULTS: Baroreflex sensitivity was lower in the hypertensive diabetic group than it was in the normotensive diabetic group (p < 0.05). The early and delayed myocardial uptake of 123I-MIBG was lower (p < 0.01 and p < 0.05, respectively), and the percent washout rate of 123I-MIBG was higher (p < 0.05) in the hypertensive diabetic group. However, the high frequency (HF) power and the ratio of low frequency (LF) power to HF power (LF/HF) of HRV and plasma norepinephrine concentration were not significantly different. The homeostasis model assessment index was higher in the hypertensive diabetic group than it was in the normotensive diabetic group (p < 0.01). CONCLUSIONS: Our results indicate that essential hypertension acts synergistically with type 2 diabetes to depress cardiac reflex vagal and sympathetic function, and the results also suggest that insulin resistance may play a pathogenic role in these processes.


Subject(s)
Autonomic Nervous System/physiopathology , Diabetes Mellitus, Type 2/physiopathology , Diabetic Angiopathies/physiopathology , Heart/innervation , Hypertension/physiopathology , 3-Iodobenzylguanidine , Baroreflex/physiology , Female , Heart Function Tests , Heart Rate , Humans , Insulin Resistance/physiology , Male , Middle Aged , Norepinephrine/blood , Radiopharmaceuticals
5.
Am J Physiol Cell Physiol ; 280(5): C1255-61, 2001 May.
Article in English | MEDLINE | ID: mdl-11287339

ABSTRACT

Effects of growth hormone (GH), insulin-like growth factor I (IGF-I), and endothelin-1 (ET-1) on endothelial cell migration and the underlying molecular mechanisms were explored using a human umbilical cord endothelial cell line, ECV304 cells, in vitro. Treatment of the cells with IGF-I or ET-1, but not GH, stimulated the cell migration. Interestingly, however, ET-1-induced, but not IGF-I-induced, migration of the cells was inhibited by GH. Both ET-1 and IGF-I caused activation of mitogen-activated protein kinase (MAPK) in the cells, and GH eliminated the MAPK activation produced by ET-1 but not that produced by IGF-I. On the other hand, migration of the cells was stimulated by protein kinase C (PKC) agonist, phorbol 12-myristate 13-acetate. ET-1 promoted PKC activity, and a PKC inhibitor, GF-109203X, blocked ET-1-induced cell migration. Although GH inhibited ET-1-induced cell migration and MAPK activity, it did not block ET-1-induced PKC activation. Thus ET-1 stimulation of endothelial cell migration appears to be mediated by PKC/MAPK pathway, and GH may inhibit the MAPK activation by ET-1 at the downstream of PKC.


Subject(s)
Endothelium, Vascular/physiology , Human Growth Hormone/pharmacology , Insulin-Like Growth Factor I/pharmacology , Cell Line , Cell Movement/drug effects , Cell Movement/physiology , Endothelin-1/pharmacology , Endothelium, Vascular/cytology , Endothelium, Vascular/drug effects , Enzyme Inhibitors/pharmacology , Epidermal Growth Factor/pharmacology , Humans , Indoles/pharmacology , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Maleimides/pharmacology , Mitogen-Activated Protein Kinases/metabolism , Protein Kinase C/metabolism , Recombinant Proteins/pharmacology , Signal Transduction/drug effects , Signal Transduction/physiology , Tetradecanoylphorbol Acetate/pharmacology
6.
J Biol Chem ; 276(18): 15292-7, 2001 May 04.
Article in English | MEDLINE | ID: mdl-11278545

ABSTRACT

Various studies have demonstrated that the platelet-derived growth factor (PDGF) receptor in adipocytes can activate PI 3-kinase activity without affecting insulin-responsive glucose transporter (GLUT4) translocation. To investigate this phenomenon of receptor signaling specificity, we utilized single cell analysis to determine the cellular distribution and signaling properties of PDGF and insulin in differentiated 3T3L1 adipocytes. The insulin receptor was highly expressed in a large percentage of the cell population (>95%) that also expressed caveolin 2 and GLUT4 with very low levels of the PDGF receptor. In contrast, the PDGF receptor was only expressed in approximately 10% of the differentiated 3T3L1 cell population with relatively low levels of the insulin receptor, caveolin 2, and GLUT4. Consistent with this observation, insulin stimulated the phosphorylation of Akt in the caveolin 2- and GLUT4-positive cells, whereas PDGF primarily stimulated Akt phosphorylation in the caveolin 2- and GLUT4-negative cell population. Furthermore, transfection of the PDGF receptor in the insulin receptor-, GLUT4-, and caveolin 2-positive cells resulted in the ability of PDGF to stimulate GLUT4 translocation. These data demonstrate that differentiated 3T3L1 adipocytes are not a homogeneous population of cells, and the lack of PDGF receptor expression in the GLUT4-positive cell population accounts for the inability of the endogenous PDGF receptor to activate GLUT4 translocation.


Subject(s)
Adipocytes/cytology , Muscle Proteins , Receptor Protein-Tyrosine Kinases/metabolism , Signal Transduction , 3T3 Cells , Animals , Glucose Transporter Type 4 , Humans , Mice , Monosaccharide Transport Proteins/metabolism , Protein Isoforms/metabolism , Receptors, Platelet-Derived Growth Factor/metabolism
7.
Am Psychol ; 56(1): 65-70, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11242990

ABSTRACT

The development of family psychology and family therapy in Japan has occurred mostly since the 1980s. This development was originally activated by the major social issue in contemporary Japan of school refusal, in which more than 127,000 children either overtly refuse to or claim that they cannot go to school. From a family perspective, this problem is analyzed as it relates to the confusion that children experience from unbalanced and unclear boundaries in family relations or "membranes." An approach to family therapy that adapts systems theory and integrates a clay sculpting medium has been developed to work with Japanese families confronting this problem. The design and implementation of preventative family psychology programs applied at the community level are also an important part of the future development in these fields.


Subject(s)
Family Therapy/methods , Family/psychology , Mental Disorders/therapy , Psychology/trends , Humans , Japan
8.
Am J Physiol Heart Circ Physiol ; 280(1): H441-54, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11123262

ABSTRACT

We sought to determine the mechanisms whereby brief administration of bradykinin (bradykinin preconditioning, BK-PC) before prolonged ischemia followed by reperfusion (I/R) prevents postischemic microvascular dysfunction. Intravital videomicroscopic approaches were used to quantify I/R-induced leukocyte/endothelial cell adhesive interactions and microvascular barrier disruption in single postcapillary venules of the rat mesentery. I/R increased the number of rolling, adherent, and emigrated leukocytes and enhanced venular albumin leakage, effects that were prevented by BK-PC. The anti-inflammatory effects of BK-PC were largely prevented by concomitant administration of a B(2)-receptor antagonist but not by coincident B(1) receptor blockade, nitric oxide (NO) synthase inhibition, or cyclooxygenase blockade. However, NO synthase blockade during reperfusion after prolonged ischemia was effective in attenuating the anti-inflammatory effects of BK-PC. Pan protein kinase C (PKC) inhibition antagonized the beneficial effects of BK-PC but only when administered during prolonged ischemia. In contrast, specific inhibition of the conventional PKC isotypes failed to alter the effectiveness of BK-PC. These results indicate that bradykinin can be used to pharmacologically precondition single mesenteric postcapillary venules to resist I/R-induced leukocyte recruitment and microvascular barrier dysfunction by a mechanism that involves B(2) receptor-dependent activation of nonconventional PKC isotypes and subsequent formation of NO.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Bradykinin/pharmacology , Ischemic Preconditioning , Animals , Bradykinin/analogs & derivatives , Bradykinin/physiology , Bradykinin Receptor Antagonists , Capillaries , Cell Adhesion , Chemotaxis, Leukocyte , Enzyme Inhibitors/pharmacology , Leukocytes/physiology , Male , Mesentery/metabolism , Nitrates/blood , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase Type III , Nitrites/blood , Protein Kinase C/antagonists & inhibitors , Rats , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Reperfusion Injury/physiopathology , omega-N-Methylarginine/pharmacology
9.
Nature ; 407(6801): 202-7, 2000 Sep 14.
Article in English | MEDLINE | ID: mdl-11001060

ABSTRACT

Insulin stimulates the transport of glucose into fat and muscle cells. Although the precise molecular mechanisms involved in this process remain uncertain, insulin initiates its actions by binding to its tyrosine kinase receptor, leading to the phosphorylation of intracellular substrates. One such substrate is the Cbl proto-oncogene product. Cbl is recruited to the insulin receptor by interaction with the adapter protein CAP, through one of three adjacent SH3 domains in the carboxy terminus of CAP. Upon phosphorylation of Cbl, the CAP-Cbl complex dissociates from the insulin receptor and moves to a caveolin-enriched, triton-insoluble membrane fraction. Here, to identify a molecular mechanism underlying this subcellular redistribution, we screened a yeast two-hybrid library using the amino-terminal region of CAP and identified the caveolar protein flotillin. Flotillin forms a ternary complex with CAP and Cbl, directing the localization of the CAP-Cbl complex to a lipid raft subdomain of the plasma membrane. Expression of the N-terminal domain of CAP in 3T3-L1 adipocytes blocks the stimulation of glucose transport by insulin, without affecting signalling events that depend on phosphatidylinositol-3-OH kinase. Thus, localization of the Cbl-CAP complex to lipid rafts generates a pathway that is crucial in the regulation of glucose uptake.


Subject(s)
Caveolins , Cytoskeletal Proteins/metabolism , Glucose/metabolism , Insulin/metabolism , Membrane Lipids/metabolism , Muscle Proteins , Retroviridae Proteins, Oncogenic/metabolism , Signal Transduction , 3T3 Cells , Aminopeptidases/metabolism , Animals , Biological Transport , Caveolin 1 , Cell Line , Cystinyl Aminopeptidase , Glucose Transporter Type 4 , Membrane Proteins/metabolism , Mice , Monosaccharide Transport Proteins/metabolism , Oncogene Protein v-cbl , Phosphorylation , Two-Hybrid System Techniques
10.
Br J Pharmacol ; 130(4): 767-76, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10864882

ABSTRACT

A newly synthesized benzothiazepine derivative, JTV-519 (JT) has been reported to be cardioprotective. However, the precise mechanism underlying the cardioprotective effect of this drug is unknown. Coronary-perfused guinea-pig ventricular muscles were subjected to 20-min no-flow ischaemia followed by 60-min reperfusion (I/R). I/R significantly decreased the contraction in untreated preparations (control group, 34+/-4% of baseline value, n=6). Brief administration of JT (1.0 microM) prior to ischaemia significantly improved the postischaemic contractile recovery (63+/-5% of baseline value, n=4), as compared to the control group. JT (1.0 microM) slightly prolonged action potential duration before ischaemia and induced conduction disturbance (2 : 1 block) after the initiation of ischaemia. The cardioprotective effect of JT was antagonized by chelerythrine (CH, 5.0 microM), an inhibitor of protein kinase C (PKC) or by 5-hydroxydecanoic acid (5-HD, 400 microM), an inhibitor of mitochondrial ATP-sensitive K(+) (K(ATP)) channels. These results suggest that the protective effect of JT is due to the opening of mitochondrial K(ATP) channels, which, in turn, is linked to PKC activation.


Subject(s)
Calcium Channel Blockers/pharmacology , Heart Ventricles/drug effects , Myocardial Contraction/drug effects , Myocardial Reperfusion Injury/prevention & control , Thiazepines/pharmacology , Action Potentials/drug effects , Adenosine Triphosphate/physiology , Alkaloids , Animals , Benzophenanthridines , Decanoic Acids/pharmacology , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Guinea Pigs , Hydroxy Acids/pharmacology , In Vitro Techniques , Mitochondria, Heart/drug effects , Mitochondria, Heart/physiology , Myocardial Ischemia/complications , Myocardial Reperfusion/adverse effects , Myocardial Reperfusion Injury/etiology , Perfusion , Phenanthridines/pharmacology , Potassium Channels/drug effects , Potassium Channels/metabolism , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/metabolism , Ventricular Function
11.
J Biol Chem ; 275(27): 20880-6, 2000 Jul 07.
Article in English | MEDLINE | ID: mdl-10764799

ABSTRACT

The effects of a high concentration of glucose on the insulin receptor-down signaling were investigated in human hepatoma (HepG2) cells in vitro to delineate the molecular mechanism of insulin resistance under glucose toxicity. Treatment of the cells with high concentrations of glucose (15-33 mm) caused phosphorylation of serine residues of the insulin receptor substrate 1 (IRS-1), leading to reduced electrophoretic mobility of it. The phosphorylation of IRS-1 with high glucose treatment was blocked only by protein kinase C (PKC) inhibitors. The high glucose treatment attenuated insulin-induced association of IRS-1 and phosphatidylinositol 3-kinase and insulin-stimulated phosphorylation of Akt. A metabolic effect of insulin, stimulation of glycogen synthesis, was also inhibited by the treatment. In contrast, insulin-induced association of Shc and Grb2 was not inhibited. Treatment of the cells with high glucose promoted the translocation of PKCepsilon and PKCdelta from the cytosol to the plasma membrane but not that of other PKC isoforms. Finally, PKCepsilon and PKCdelta directly phosphorylated IRS-1 under cell-free conditions. We conclude that a high concentration of glucose causes phosphorylation of IRS-1, leading to selective attenuation of metabolic signaling of insulin. PKCepsilon and PKCdelta are involved in the down-regulation of insulin signaling, and they may lie in a pathway regulating the phosphorylation of IRS-1.


Subject(s)
Adaptor Proteins, Signal Transducing , Adaptor Proteins, Vesicular Transport , Glucose/pharmacology , Proto-Oncogene Proteins , Receptor, Insulin/metabolism , Signal Transduction/drug effects , Carcinoma, Hepatocellular , Down-Regulation/drug effects , GRB2 Adaptor Protein , Glycogen/biosynthesis , Humans , Insulin Receptor Substrate Proteins , Isoenzymes/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphoamino Acids/analysis , Phosphoproteins/metabolism , Phosphorylation , Protein Kinase C/metabolism , Protein Serine-Threonine Kinases/metabolism , Proteins/metabolism , Proto-Oncogene Proteins c-akt , Shc Signaling Adaptor Proteins , Src Homology 2 Domain-Containing, Transforming Protein 1 , Tumor Cells, Cultured
12.
Psychiatry ; 63(4): 371-84, 2000.
Article in English | MEDLINE | ID: mdl-11218560

ABSTRACT

Clinical work with minorities in Japan is a relatively new and rapidly growing field. An influx of migrants from the 1970s has required psychiatrists to work with culturally different patients, yet few are experienced or trained in this area. With an even more radical population change imminent, skills in working with people of diverse cultural backgrounds are becoming a pressing need. While psychiatry in Japan has long been concerned with culture, only very recently has this concern involved differences among Japanese. Psychotherapy with both new migrants and individuals from more traditional minority backgrounds involves issues of acculturation and identity. A clinical approach based on a theoretical orientation of constructivistic narrative therapy can be usefully applied to multicultural situations. A case is presented in which this approach is employed in assisting a Korean-Japanese youth to deal with identity struggles.


Subject(s)
Culture , Language , Minority Groups/psychology , Psychiatry , Psychotherapy/methods , Self Concept , Acculturation , Adult , Female , Humans , Japan , Korea/ethnology
13.
Am J Orthopsychiatry ; 69(4): 482-94, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10553459

ABSTRACT

Psychotherapeutic work in Japan with minority populations requires an understanding of their specific social and cultural context. Clinical case studies of individuals of burakumin, Korean, and mixed ancestry illustrate the complex issues of prejudice, discrimination, legal contraints, state ideology, and popular mythology of homogeneity that each brings to counseling. Clinical approaches, guided by a multicultural counseling and therapy framework, are discussed.


Subject(s)
Culture , Minority Groups/psychology , Social Support , Adult , Counseling , Cultural Diversity , Female , Humans , Japan , Korea/ethnology , Male , Psychotherapy/methods , Stress, Psychological/psychology , Stress, Psychological/therapy , United States/ethnology
14.
Am J Physiol ; 277(3): E433-8, 1999 09.
Article in English | MEDLINE | ID: mdl-10484354

ABSTRACT

Effects of high D-glucose and insulin on the endothelial cell migration and tubular formation were investigated with the use of ECV304 cells, a clonal human umbilical cord endothelial cell line. Exposure of the cells to high D-glucose resulted in a marked increase in the migration, which was blocked by inhibitors of protein kinase C such as H7 (10 microM) and GF109203X (200 nM). Furthermore, a protein kinase C agonist, phorbol 12-myristate 13-acetate, had an effect similar to that of glucose on ECV304 cells. Glucose stimulation of the migration was additively enhanced by 100 nM insulin, and the insulin effect was found to be unaffected by either PD-98059 or wortmannin, a mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase inhibitor and a phosphatidylinositol 3-kinase inhibitor, respectively. Neither did H7 inhibit insulin stimulation of the migration. In contrast, a combination of high D-glucose and insulin, rather than either one alone, promoted tubular formation, which was inhibited by addition of 10 microM PD-98059. Stimulation of ECV304 cells by the combination of high D-glucose and insulin also caused an activation of MAPK, which was again obliterated by the same concentration of PD-98059. In conclusion, human endothelial cell migration and tubular formation are stimulated by high D-glucose and insulin in different ways. In the former reaction, either is effective, a combination of the two results in an additive effect, and activation of protein kinase C is involved. In contrast, tubular formation will only occur in the presence of a combination of high D-glucose and insulin, and MAPK plays an essential role.


Subject(s)
Endothelium, Vascular/drug effects , Endothelium, Vascular/physiology , Glucose/pharmacology , Insulin/pharmacology , Cell Line , Cell Movement/drug effects , Drug Combinations , Endothelium, Vascular/cytology , Enzyme Inhibitors/pharmacology , Humans , Protein Kinase C/antagonists & inhibitors
15.
Am J Physiol ; 277(1): H152-60, 1999 07.
Article in English | MEDLINE | ID: mdl-10409193

ABSTRACT

The results of several recent studies indicate that bradykinin protects tissues against the deleterious effects of ischemia-reperfusion (I/R). However, other studies indicate that bradykinin can act as a proinflammatory agent, inducing P-selectin expression, the formation of chemotactic stimuli, and endothelial barrier disruption. In the present study, we used intravital microscopic techniques to examine the dose-dependent effects of bradykinin on leukocyte-endothelial cell interactions, the formation of platelet-leukocyte aggregates, and venular hemodynamics in rat mesentery in an attempt to explain these divergent findings. Superfusion of the mesentery with low concentrations of bradykinin (/=10(-6) M) decreased V(RBC), increased the number of platelet-leukocyte aggregates, and induced leukocyte adhesion in single postcapillary venules. The formation of platelet-leukocyte aggregates and increased leukocyte adhesion induced by high-dose bradykinin were attenuated by administration of a B(2)-receptor (HOE-140) or a platelet-activating factor (PAF, WEB-2086) antagonist. Thus these adhesive interactions induced by high-dose bradykinin appear to be mediated by a mechanism that is dependent on B(2)-receptor activation and the formation of PAF or PAF-like lipids. The effects of bradykinin on venular V(RBC) and blood flow were also concentration dependent, with low doses producing nitric oxide-mediated vasodilation, whereas high doses decreased V(RBC) by a mechanism that is PAF independent.


Subject(s)
Bradykinin/administration & dosage , Chemotaxis, Leukocyte/drug effects , Hemodynamics/drug effects , Mesentery/blood supply , Animals , Azepines/pharmacology , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Bradykinin Receptor Antagonists , Dose-Response Relationship, Drug , Erythrocytes/drug effects , Erythrocytes/physiology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Rats , Rats, Sprague-Dawley , Triazoles/pharmacology , Venules
16.
Am J Physiol ; 277(1): H161-71, 1999 07.
Article in English | MEDLINE | ID: mdl-10409194

ABSTRACT

Although a number of recent reports indicate that bradykinin attenuates ischemia- reperfusion (I/R)-induced tissue injury, the mechanisms underlying its protective actions are not fully understood. However, because bradykinin induces endothelial nitric oxide (NO) production and NO donors have been shown to attenuate postischemic leukocyte adhesion, endothelial barrier disruption, and tissue injury, we hypothesized that bradykinin may act to reduce I/R-induced tissue injury by preventing leukocyte recruitment and preserving microvascular barrier function. To address this postulate, we used intravital videomicroscopic approaches to quantify leukocyte-endothelial cell interactions and microvascular barrier function in single postcapillary venules in the rat mesentery. Reperfusion after 20 min of ischemia significantly decreased wall shear rate and leukocyte rolling velocity, increased the number of rolling, adherent, and emigrated leukocytes, and disrupted the microvascular barrier as evidenced by enhanced venular albumin leakage. Superfusion of the mesentery with bradykinin (10 nM) during I/R significantly reduced these deleterious effects of I/R. Although these inhibitory effects of bradykinin were not affected by cyclooxygenase blockade with indomethacin (10 microM), coadministration with NO synthase (N(omega)-nitro-L-arginine methyl ester, 10 microM) or bradykinin B(2)-receptor (HOE-140, 1 microM) antagonists abolished the protective actions of bradykinin. Plasma NO concentration was measured in the mesenteric vein and was significantly decreased after I/R, an effect that was prevented by bradykinin treatment. These results indicate that bradykinin attenuates I/R-induced leukocyte recruitment and microvascular dysfunction by a mechanism that involves bradykinin B(2)-receptor-dependent NO production.


Subject(s)
Bradykinin/physiology , Capillary Permeability/physiology , Chemotaxis, Leukocyte/physiology , Reperfusion Injury/blood , Animals , Bradykinin/analogs & derivatives , Bradykinin/pharmacology , Bradykinin Receptor Antagonists , Capillary Permeability/drug effects , Chemotaxis, Leukocyte/drug effects , Male , NG-Nitroarginine Methyl Ester/pharmacology , Rats , Rats, Sprague-Dawley , Venules/drug effects , Venules/physiology
17.
J Mol Cell Cardiol ; 31(4): 895-906, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10329216

ABSTRACT

Cardiac Na-Ca exchange is related to the intracellular calcium overload that occurs during ischemia and reperfusion. However, direct observation of the membrane current through Na-Ca exchange during ischemia has not been performed. The purpose of this study was to clarify the effect of simulated ischemia (substrate-free anoxia) and intracellular acidification on the Na-Ca exchange current. The electrogenic Na-Ca exchange current was recorded from isolated guinea-pig ventricular myocytes by using patch-clamp techniques. Exposure to anoxia significantly decreased both the inward and outward directed Na-Ca exchange currents (from -1.21+/-0. 18 to -0.04+/-0.32 pA/pF at -80 mV; from 6.58+/-1.06 to 3.14+/-1.06 pA/pF at +40 mV). The reversal potential of Na-Ca exchange current shifted to negative direction during anoxia. Subsequent reoxygenation rapidly restored the amplitude of exchange currents and the reversal potential. These anoxia/reoxygenation-induced changes were completely inhibited when the intracellular pH was clamped at 7.3 by using 20 m m HEPES-buffer. Furthermore, the anoxia-induced changes of Na-Ca exchange current were mimicked by the intracellular acidosis induced by a brief exposure to ammonium chloride in normoxic conditions. We conclude that the Cardiac Na-Ca exchange is suppressed by anoxia secondary to intracellular acidosis, and that these changes were reversed by reoxygenation.


Subject(s)
Calcium/metabolism , Myocardial Ischemia/metabolism , Myocardium/metabolism , Sodium/metabolism , Acidosis/metabolism , Animals , Cell Hypoxia/physiology , Guinea Pigs , Heart Ventricles/cytology , Heart Ventricles/metabolism , In Vitro Techniques , Ion Transport , Myocardial Reperfusion Injury/metabolism , Myocardium/cytology
18.
Endocr J ; 46 Suppl: S59-62, 1999 Mar.
Article in English | MEDLINE | ID: mdl-12054122

ABSTRACT

Recent studies revealed favorable para- and/or autocrine effects of IGF-1 in the pathogenesis of diabetic complications. On the other hand, hyperglycemia is a risk factor for the development of diabetic vascular complications. In this study we examined the effects of high glucose and/or IGF-1 on cell migration and angiogenesis (tubular formation) by using human endothelial cells (EC) in vitro. First we examined cell migration by the two-chamber method. Chronic treatment with a high concentration of D-glucose strongly stimulated the cell migration, which was mimicked by PMA, a protein kinase C (PKC) agonist. The cell migration was also induced by IGF-1. The glucose-induced cell migration was blocked by PKC inhibitor, H7. IGF-1-induced cell migration was not blocked by PD98059, MAPK/ERK kinase (MEK) inhibitor or wortmannin, a phosphatidylinositol (PI) 3-kinase inhibitor. Next we examined the effects of high glucose and/or IGF-1 on the tubular formation of EC. The tubular formation was induced only when the cells were exposed to a combination of high glucose and IGF-1. The tubular formation was blocked by MEK inhibitor and PI 3-kinase inhibitor but not by PKC inhibitor. These results indicate that hyperglycemia and IGF-1, respectively, stimulate the EC migration, and tubular formation is induced by a combination of IGF-1 and hyperglycemia.


Subject(s)
Cell Movement/drug effects , Endothelium, Vascular/cytology , Insulin-Like Growth Factor I/pharmacology , Neovascularization, Physiologic/drug effects , Androstadienes/pharmacology , Cell Movement/physiology , Cells, Cultured , Chromones/pharmacology , Endothelium, Vascular/drug effects , Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Glucose/adverse effects , Glucose/pharmacology , Humans , Morpholines/pharmacology , Neovascularization, Physiologic/physiology , Tetradecanoylphorbol Acetate/pharmacology , Wortmannin
19.
Surg Today ; 28(11): 1196-9, 1998.
Article in English | MEDLINE | ID: mdl-9851633

ABSTRACT

We report herein a rare case of syringomatous adenoma (SA) of the nipple. Only 22 cases of SA of the nipple have been documented in the world literature, and to the best of our knowledge this is the first case to be reported in Japan. The patient was a 68-year-old woman who presented with a painful mass in the right subareolar region of over 15 years' duration. Clinical examination including needle biopsy indicated a high possibility of carcinoma; however, the final histopathological diagnosis after mastectomy proved to be SA. SA is a benign locally infiltrating neoplasm of the nipple which shares many clinicopathological features with adenoma of the nipple. Both lesions sometimes show deceptive clinicopathological findings, causing then to be easily confused with carcinomas. However, SA can be distinguished by its unique histological appearance resembling sweat duct, or syringomatous, tumors and locally infiltrating growth, which is probably responsible for its misleading clinical findings and higher rate of recurrence. Surgeons should be aware of the possibility of diagnosing this extremely rare tumor, and the appropriate treatment.


Subject(s)
Adenoma/pathology , Breast Neoplasms/pathology , Nipples , Adenoma/surgery , Aged , Breast Neoplasms/surgery , Female , Humans , Mastectomy
20.
Kurume Med J ; 45(2): 175-9, 1998.
Article in English | MEDLINE | ID: mdl-9715044

ABSTRACT

The therapeutic role of interleukin (IL)-1 receptor antagonist, a potent inhibitor of IL-1, was investigated using peripheral blood mononuclear cells from patients with ulcerative colitis and Crohn's disease. Administration of IL-1 receptor antagonist inhibited IL-1 beta-augmented IL-1 alpha and tumor necrosis factor-alpha production by mononuclear cells. Prednisolone caused a decrease in IL-1 receptor antagonist release, whereas sulfasalazine had no modulatory effect. Interestingly, IgG caused an increase in IL-1 receptor antagonist release. In conclusion, IL-1 receptor antagonist and related molecules may have therapeutic value.


Subject(s)
Inflammatory Bowel Diseases/drug therapy , Receptors, Interleukin-1/antagonists & inhibitors , Cells, Cultured , Drug Evaluation, Preclinical , Humans
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