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1.
J Anat ; 203(4): 391-404, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14620379

RESUMEN

The role that pleural mesothelial cells play in leucocyte transmigration into the pleural cavity was investigated in lipopolysaccharide-stimulated mice. Changes in mesothelial cell morphology and changes in expression of adhesion molecules on mesothelial cells and leucocytes were analysed by light microscopy, immunohistochemistry, transmission electron microscopy (TEM) and immuno-scanning electron microscopy (immuno-SEM). After stimulation, the mesothelial cells separated completely from one another before leucocyte penetration across the mesothelial layer occurred. These changes occurred primarily in the immediate vicinity of ribs, where a large number of leucocytes accumulated. Immuno-SEM showed that the expression of intercellular adhesion molecule-1 (ICAM-1) on the parietal pleural mesothelial cells was significantly up-regulated by lipopolysaccharide stimulation, and that of vascular cell adhesion molecule-1 (VCAM-1) was induced. Both were restricted to the microvilli of the mesothelial cells. By contrast, expression of intercellular adhesion molecule-2 (ICAM-2), platelet/endothelial cell adhesion molecule-1 (PECAM-1), mucosal addressin cell adhesion molecule-1 (MAdCAM-1), endothelial leucocyte adhesion molecule-1 (ELAM-1), peripheral node addressin (PNAd) and fibronectin were not detected. Lymphocyte function associated antigen-1 (LFA-1), macrophage-1 molecule (Mac-1) and very late appearing antigen-4 (VLA-4), all ligands of ICAM-1 and VCAM-1, were present on the transmigrated neutrophils and macrophages. These findings demonstrate that the immediate vicinity of ribs is a source of leucocyte migration into the pleural space.


Asunto(s)
Células Epiteliales/fisiología , Leucocitos/fisiología , Pleura/inmunología , Animales , Antígenos de Superficie/análisis , Moléculas de Adhesión Celular , Movimiento Celular/fisiología , Selectina E/análisis , Células Epiteliales/química , Fibronectinas/análisis , Inmunoglobulinas/análisis , Inmunohistoquímica/métodos , Integrina alfa4beta1/análisis , Molécula 1 de Adhesión Intercelular/análisis , Leucocitos/química , Lipopolisacáridos , Antígeno-1 Asociado a Función de Linfocito/análisis , Antígeno de Macrófago-1/análisis , Masculino , Proteínas de la Membrana , Ratones , Ratones Endogámicos ICR , Microscopía Inmunoelectrónica , Mucoproteínas/análisis , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Pleura/ultraestructura , Organismos Libres de Patógenos Específicos , Molécula 1 de Adhesión Celular Vascular/análisis
2.
Drug Metab Dispos ; 27(11): 1254-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10534309

RESUMEN

Isoforms of cytochrome P-450 (CYP) involved in the metabolism of gallopamil enantiomers were identified by measuring the disappearance rate of parent drug from an incubation mixture with human liver microsomes and recombinant human CYPs. Mean (+/- S.D.) intrinsic clearances (CL(int)) of R(+)- and S(-)-gallopamil in human liver microsomes were 0.320 +/- 0.165 and 0.205 +/- 0.107 ml/min/mg protein, respectively. These values were highly correlated with the 6beta-hydroxylation activity of testosterone, a marker substrate of CYP3A4 (r = 0.977 and 0.900 for R(+)- and S(-)-gallopamil, respectively, p <.001). Ketoconazole and troleandomycin, selective inhibitors of CYP3A4, and polyclonal antibodies raised against CYP3A4/5 markedly reduced the CL(int) of gallopamil enantiomers in human liver microsomes. Among the 10 recombinant human CYP isoforms, CYP3A4 exhibited the highest CL(int) of gallopamil enantiomers, and CYP2C8 and CYP2D6 also exhibited appreciable activity. When the contribution of CYP3A4 to the total metabolic clearance of gallopamil enantiomers in human liver microsomes was estimated by relative activity factor, the mean (+/- S.D.) contributions were 92 +/- 18 and 68 +/- 19% for R(+)- and S(-)-gallopamil, respectively. These values were comparable to the rates of immunoinhibition by antibodies raised against CYP3A4/5 observed in human liver microsomes. The present study suggests that CYP3A4 is a major isoform involved in the overall metabolic clearance of gallopamil enantiomers in the human liver, and that the present approach based on disappearance rate may be applicable to identify major isoforms of CYP involved in the metabolism of a drug in human liver microsomes.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Galopamilo/metabolismo , Isoenzimas/metabolismo , Galopamilo/química , Humanos , Microsomas Hepáticos/enzimología , Microsomas Hepáticos/metabolismo , Proteínas Recombinantes/metabolismo , Estereoisomerismo
3.
Clin Pharmacol Ther ; 66(3): 265-74, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10511062

RESUMEN

BACKGROUND AND PURPOSE: A triple therapy with omeprazole, amoxicillin (INN, amoxicilline), and clarithromycin is widely used for the eradication of Helicobacter pylori. Omeprazole and clarithromycin are metabolized by CYP2C19 and CYP3A4. This study aimed to elucidate whether clarithromycin affects the metabolism of omeprazole. METHODS: After administration of placebo or 400 mg clarithromycin twice a day for 3 days, 20 mg omeprazole and placebo or 400 mg clarithromycin were administered to 21 healthy volunteers. Plasma concentrations of omeprazole and clarithromycin and their metabolites were determined before and 1, 2, 3, 5, 7, 10, and 24 hours after dosing. CYP2C19 genotype status was determined by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Subjects were classified into three groups on the basis of PCR-RFLP analyses for CYP2C19: homozygous extensive metabolizer group (n = 6), heterozygous extensive metabolizer group (n = 11), and poor metabolizer group (n = 4). Mean area under the plasma concentration-time curves from 0 to 24 hours (AUC) of omeprazole in the homozygous extensive metabolizer, heterozygous extensive metabolizer, and poor metabolizer groups were significantly increased by clarithromycin from 383.9 to 813.1, from 1001.9 to 2110.4, and from 5589.7 to 13098.6 ng x h/mL, respectively. There were significant differences in the mean AUC values of clarithromycin among the three groups. CONCLUSION: Clarithromycin inhibits the metabolism of omeprazole. Drug interaction between clarithromycin and omeprazole may underlie high eradication rates achieved by triple therapy with omeprazole, amoxicillin, and clarithromycin.


Asunto(s)
Antibacterianos/farmacología , Antiulcerosos/farmacocinética , Hidrocarburo de Aril Hidroxilasas , Claritromicina/farmacología , Sistema Enzimático del Citocromo P-450/genética , Oxigenasas de Función Mixta/genética , Omeprazol/farmacocinética , Inhibidores de la Síntesis de la Proteína/farmacología , Adulto , Antiulcerosos/antagonistas & inhibidores , Antiulcerosos/sangre , Área Bajo la Curva , Citocromo P-450 CYP2C19 , Inhibidores Enzimáticos/farmacocinética , Femenino , Genotipo , Heterocigoto , Homocigoto , Humanos , Masculino , Omeprazol/antagonistas & inhibidores , Omeprazol/sangre , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Valores de Referencia , Voluntarios
4.
Ergonomics ; 38(9): 1921-31, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7671867

RESUMEN

Based on a study of human hand movements during practical diagnosis, evaluation patterns of softness and elasticity were observed. The evaluation models were extracted from these analyses and applied to the developing a method of detecting the dynamic properties of human skin. The device consisted of a robot arm controlled by microcomputer system and a probe with a mounted mechanical strain gauge. A method was developed to measure the dynamic properties of human skin. Correlations were obtained between parameters from the measurements and the values evaluated by experts. The dynamic properties of the cheek skins of a panel of 86 people, aged from 20 to 75 years, were measured. A remarkable reduction in elasticity was observed in older people and the lack of sebum was analysed. From these results the metabolism in the skin surface and the muscles of the cheeks were analysed. The effects of skin care products were then confirmed by measuring cheeks before and after continual use of facial treatment systems for a month. Significant recovery effects were observed in a less soft-skinned group and a less elastic-skinned group over 30 years of age. These experiments suggest a protecting effect of facial treatments and skin care products.


Asunto(s)
Envejecimiento/fisiología , Masaje , Fenómenos Fisiológicos de la Piel , Adulto , Anciano , Elasticidad , Cara , Humanos , Persona de Mediana Edad , Robótica , Sebo , Piel/química
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