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1.
Clin Pharmacol Ther ; 100(3): 259-67, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27256812

RESUMEN

This article reports the clinical investigation of a probe drug cocktail containing substrates of key drug transporters. Single oral doses of 0.25 mg digoxin (P-gp), 5 mg furosemide (OAT1 and OAT3), 500 mg metformin (OCT2, MATE1, and MATE2-K), and 10 mg rosuvastatin (OATP1B1, OATP1B3, and BCRP) were administered separately or as a cocktail in a randomized six-period crossover trial in 24 healthy male volunteers. As a cocktail, relative bioavailabilities of digoxin and metformin and furosemide AUC0-tz were similar to separate dosing. However, when administered as a cocktail the Cmax of furosemide was 19.1% lower and the Cmax and AUC0-tz of rosuvastatin were 38.6% and 43.4% higher, respectively. In addition, the effects of increased doses of metformin or furosemide on the cocktail were investigated in 11 and 12 subjects, respectively. The cocktail explored in this trial has the potential to be used for the in vivo screening of transporter-mediated drug-drug interactions. © 2016 American Society for Clinical Pharmacology and Therapeutics.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas de Transporte de Catión/metabolismo , Digoxina/farmacocinética , Furosemida/farmacocinética , Metformina/farmacocinética , Rosuvastatina Cálcica/farmacocinética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Adulto , Área Bajo la Curva , Estudios Cruzados , Digoxina/farmacología , Interacciones Farmacológicas , Furosemida/farmacología , Humanos , Transportador 1 de Anión Orgánico Específico del Hígado/metabolismo , Masculino , Tasa de Depuración Metabólica , Metformina/farmacología , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Proteína 1 de Transporte de Anión Orgánico/metabolismo , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Proteínas de Transporte de Catión Orgánico/metabolismo , Transportador 2 de Cátion Orgánico , Rosuvastatina Cálcica/farmacología , Miembro 1B3 de la Familia de los Transportadores de Solutos de Aniones Orgánicos
2.
Eur Cell Mater ; 29: 82-94; discussion 95-6, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25612543

RESUMEN

Ultraviolet (UV) light treatment of implant surfaces has been demonstrated to enhance their bioactivity significantly. This study examined the effect of UV treatment of different zirconia surfaces on the response of primary human alveolar bone-derived osteoblasts (PhABO). Disks of two zirconia-based materials with two different surface topographies (smooth, roughened) were exposed to UV light. Qualitative and quantitative assessment of PhABO on zirconia surfaces, by means of immunofluorescence, scanning electron microscopy and DNA quantification at 4 and 24 h revealed a higher number of initially attached osteoblasts on UV-treated surfaces. Cell area and perimeter were significantly larger on all UV-treated surfaces (p<0.05). The proliferation activity was significantly higher on both roughened UV-treated surfaces than on untreated samples at day 3 of culture (p<0.05). The expression levels of collagen I, osteopontin and osteocalcin at day 14 and alkaline phosphatase activity at day 7 and 14 of culture period were similar among UV-treated and untreated surfaces. Alizarin-Red-Staining at day 21 demonstrated significantly more mineralised nodules on UV-treated samples than on untreated samples. Contact angle measurements and X-ray photoelectron spectroscopy showed that UV light transformed zirconia surfaces from hydrophobic to (super-) hydrophilic (p<0.05) and significantly reduced the atomic percentage of surface carbon. The results showed that UV light pre-treatment of zirconia surfaces changes their physicochemical properties and improves their attractiveness against PhABO, primarily demonstrated by an augmented cell attachment and spreading. This may result in faster healing and better bone-to-implant contact of zirconia implants in vivo following such a pre-treatment.


Asunto(s)
Materiales Biocompatibles/química , Implantes Dentales , Osteoblastos/citología , Rayos Ultravioleta , Circonio/química , Fosfatasa Alcalina/metabolismo , Proceso Alveolar/citología , Materiales Biocompatibles/farmacología , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Fenómenos Químicos/efectos de la radiación , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Expresión Génica/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas/efectos de la radiación , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Osteoblastos/metabolismo , Osteoblastos/ultraestructura , Osteocalcina/genética , Osteopontina/genética , Espectroscopía de Fotoelectrones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo
3.
Herz ; 36(5): 438-43, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21344270

RESUMEN

BACKGROUND: Left ventricular inferoseptal clefts are a localized variant of myocardial structure, easily overlooked but potentially raising concern when identified through imaging. CASE STUDY: Here we illustrate and describe inferoseptal clefts by means of multimodality imaging and consider them in relation to possible differential diagnoses. A 49-year-old male patient was investigated for chest pain and found to have multiple inferoseptal clefts. The pain subsequently resolved and was thought to have been pleuritic. There was no evidence or family history of hypertrophic cardiomyopathy. The diagnosis of clefts was arrived at after consultation with several cardiac imaging specialists and the few available relevant published reports. Echocardiography, cardiovascular magnetic resonance, invasive ventriculography and computed tomography each showed the clefts in relation to surrounding compact and contractile myocardium of the inferoseptal region, which occluded the clefts in systole. In terms of location, orientation and systolic occlusion the inferoseptal clefts resembled the isolated clefts reported in healthy volunteers, and have features in common with crypts reported in carriers of a genetic mutation associated with hypertrophic cardiomyopathy (HCM). The incidence and implications of multiple inferoseptal clefts have yet to be determined. CONCLUSION: Multimodality imaging permits clear depiction of left ventricular inferoseptal clefts, which should be distinguished from different entities such as left ventricular noncompaction cardiomyopathy (LVNC), cardiac diverticula and cardiac aneurysms. Inferoseptal clefts have yet to be widely recognized as a distinct variant of regional left ventricular structure.


Asunto(s)
Dolor en el Pecho/etiología , Diagnóstico por Imagen , Cardiopatías Congénitas/diagnóstico , Ventrículos Cardíacos/anomalías , Procesamiento de Imagen Asistido por Computador , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/genética , Diagnóstico Diferencial , Tamización de Portadores Genéticos , Cardiopatías Congénitas/genética , Humanos , Masculino , Persona de Mediana Edad
4.
Dtsch Med Wochenschr ; 133(3): 87-91, 2008 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-18186011

RESUMEN

Cardiovascular magnetic resonance imaging (MRI) demonstrates location, activity and extent of inflammation in acute myocarditis. A combined approach, using different imaging modalities (T2-IR-weighted imaging, early and late gadolinium enhancement) provides high diagnostic accuracy. The type of myocardial virus infection (PVB19, HHV6) may be related to the pattern of inflammation demonstrated by cardiovascular MRI and the clinical course. Whether specific patterns of late gadolinium enhancement in myocarditis are associated with poor prognosis remains a subject for further investigation. Cardiovascular MRI in myocarditis is believed to become a significant imaging tool in identifying patients at risk for heart failure and ventricular arrhythmias. These patients may need specific treatment, such as antiviral or immunosuppressive medication, dependent on the result of endomyocardial biopsy.


Asunto(s)
Imagen por Resonancia Magnética , Miocarditis/diagnóstico , Virosis/diagnóstico , Enfermedad Aguda , Humanos , Miocarditis/patología , Miocarditis/virología , Pronóstico , Sensibilidad y Especificidad
5.
Plant J ; 28(3): 319-32, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11722774

RESUMEN

Fruit ripening is characterized by dramatic changes in gene expression, enzymatic activities and metabolism. Although the process of ripening has been studied extensively, we still lack valuable information on how the numerous metabolic pathways are regulated and co-ordinated. In this paper we describe the characterization of FaMYB1, a ripening regulated strawberry gene member of the MYB family of transcription factors. Flowers of transgenic tobacco lines overexpressing FaMYB1 showed a severe reduction in pigmentation. A reduction in the level of cyanidin 3-rutinoside (an anthocyanin) and of quercetin-glycosides (flavonols) was observed. Expression of late flavonoid biosynthesis genes and their enzyme activities were adversely affected by FaMYB1 overexpression. Two-hybrid assays in yeast showed that FaMYB1 could interact with other known anthocyanin regulators, but it does not act as a transcriptional activator. Interestingly, the C-terminus of FaMYB1 contains the motif pdLNL(D)/(E)Lxi(G)/S. This motif is contained in a region recently proposed to be involved in the repression of transcription by AtMYB4, an Arabidopsis MYB protein. Our results suggest that FaMYB1 may play a key role in regulating the biosynthesis of anthocyanins and flavonols in strawberry. It may act to repress transcription in order to balance the levels of anthocyanin pigments produced at the latter stages of strawberry fruit maturation, and/or to regulate metabolite levels in various branches of the flavonoid biosynthetic pathway.


Asunto(s)
Antocianinas/biosíntesis , Flavonoides/biosíntesis , Nicotiana/genética , Proteínas Proto-Oncogénicas c-myb , Rosales/metabolismo , Secuencia de Aminoácidos , Antocianinas/genética , Proteínas de Arabidopsis , Proteínas de Unión al ADN , Flavonoles , Frutas/enzimología , Frutas/genética , Frutas/crecimiento & desarrollo , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Pigmentación/genética , Pigmentación/fisiología , Proteínas de Plantas , Rosales/enzimología , Homología de Secuencia de Aminoácido , Transcripción Genética
6.
J Am Soc Echocardiogr ; 14(6): 646-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11391297

RESUMEN

A case of bacterial aortitis of the ascending aorta caused by Staphylococcus aureus progressed to an aortic mycotic aneurysm. Transesophageal echocardiography was the diagnostic approach of choice. The different stages of the disease from the initial aortic wall infection to formation of an abscess that communicated with the aortic lumen were documented by transesophageal echocardiography.


Asunto(s)
Aneurisma Infectado/diagnóstico por imagen , Aneurisma de la Aorta/diagnóstico por imagen , Aortitis/diagnóstico por imagen , Ecocardiografía Transesofágica , Infecciones Estafilocócicas/diagnóstico por imagen , Aortitis/microbiología , Progresión de la Enfermedad , Humanos , Masculino , Persona de Mediana Edad
7.
J Agric Food Chem ; 49(5): 2427-32, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368615

RESUMEN

Isotopically labeled D-glucose, D-fructose, 1-deoxy-D-fructose, and 6-deoxyhexoses were applied to detached ripening strawberry (Fragaria x ananassa) fruits, and the incorporation of the isotopes into the key strawberry aroma compounds 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF, 1) and 2,5-dimethyl-4-methoxy-3(2H)-furanone (DMMF, 2) was determined by gas chromatography-mass spectrometry. In contrast to previous reports the data clearly showed that 6-deoxy-D-fructose/6-deoxy-D-glucose and 1-deoxy-D-fructose are not natural precursors of the furanones. However, isotopically labeled 1 and 2 were observed after the application of [1-(2)H]-, [2-(2)H]-, and [6,6-(2)H(2)]-D-glucose as well as [U-(13)C(6)]-, [1-(13)C]-, [1-(2)H]-, [6,6-(2)H(2)]-D-fructose. The isotope label of [4-(2)H]-D-glucose was not recovered in the furanones. In contrast, [2-(2)H]-D-glucose was converted to [1- or 6-(2)H]-1 and [1- or 6-(2)H]-2 by the strawberry fruits. The observed isotope shift can be explained by the catalysis of phosphohexose isomerase in the course of the biogenesis of the hydroxyfuranone (1) and the methoxyfuranone (2) from D-glucose. Thus, the applied D-glucose is metabolized to D-fructose-6-phosphate prior to the transformation into the furanones.


Asunto(s)
Frutas/metabolismo , Furanos/metabolismo , Frutas/química , Furanos/análisis , Cromatografía de Gases y Espectrometría de Masas , Marcaje Isotópico , Odorantes , Gusto
8.
J Biosci Bioeng ; 91(4): 352-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-16233003

RESUMEN

2,5-Dimethyl-4-hydroxy-3(2H)-furanone (DMHF) is an important aroma compound found in many fruits such as strawberries and pineapples and it is also produced by the soy-sauce-fermenting yeast Zygosaccharomyces rouxii after the addition of d-fructose-1,6-diphosphate to yeast-peptone-dextrose nutrient media. Dilute DMHF solutions exhibit a strawberry-like flavor while DMHF concentrates have a caramel-like aroma. In media containing D-fructose-1,6-diphosphate as the sole carbon source, growth of Z. rouxii and formation of DMHF were not observed. Although Z. rouxii cells grew in media with D-glucose as the sole carbon source, DMHF was only produced when media were supplemented with D-fructose-1,6-diphosphate. The DMHF concentration always correlated with the yeast cell count and D-fructose-1,6-diphosphate concentration. Addition of CaCl2 (up to 50 g.l(-1)) led to a higher DMHF concentration. Addition of Na2SO3 reduced the growth of Z. rouxii and inhibited DMHF formation. The amount of DMHF formed by Z. rouxii was not significantly affected by the addition of KH2PO4. DMHF concentrations of 5 and 10 g.l(-1) partially and completely inhibited the growth of Z. rouxii cells, respectively. Only the singly labeled furanone was formed after the addition of 1-13C-D-fructose-1,6-diphosphate to the medium. However, unlabeled DMHF was formed in the presence of (13)C(6)-D-glucose. Therefore, the carbons of the furanone originate exclusively from exogenously supplied D-fructose-1,6-diphosphate as no exchange with the internal pool of D-fructose-1,6-diphosphate occurs. This implies that DMHF is a secondary metabolite of Z. rouxii formed from D-fructose-1,6-diphosphate. We assume that at least the first step of the metabolism of D-fructose-1,6-diphosphate takes place in the cell wall or membrane of the yeast.

9.
J Agric Food Chem ; 47(12): 5178-83, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10606591

RESUMEN

Extracts obtained by XAD solid-phase extraction of apple juice and cider were separated by liquid chromatography on silica gel. Several new 1,3-dioxanes including the known 2-methyl-4-pentyl-1,3-dioxane and 2-methyl-4-[2'(Z)-pentenyl]-1,3-dioxane, were identified in the nonpolar fractions by GC/MS analysis and confirmed by chemical synthesis. The enantioselective synthesis of the stereoisomers of the 1,3-dioxanes was performed using (R)- and (R,S)-octane-1,3-diol and (R)- and (R,S)-5(Z)-octene-1,3-diol as starting material. Comparison with the isolated products indicated that the natural products consisted of a mixture of (2S,4R) and (2R,4R) stereoisomers in the ratio of approximately 10:1, except for 1,3-dioxanes generated from acetone and 2-butanone. It is assumed that the 1, 3-dioxanes are chemically formed in the apples and cider from the natural apple ingredients (R)-octane-1,3-diol, (R)-5(Z)-octene-1, 3-diol, (3R,7R)- and (3R,7S)-octane-1,3,7-triol, and the appropriate aldehydes and ketones, which are produced either by the apples or by yeast during fermentation of the apple juice.


Asunto(s)
Bebidas/análisis , Dioxanos/aislamiento & purificación , Manipulación de Alimentos , Rosales , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectroscopía de Resonancia Magnética
11.
Biochem Biophys Res Commun ; 232(2): 364-6, 1997 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-9125182

RESUMEN

The fatty acid alpha-ketol 13-hydroxy-12-oxo-9(Z)-octadecenoic acid (methyl ester) was incubated with a bacterial culture isolated from soil. The bacteria (tentatively identified as Ralstonia sp.) exhibited strong monooxygenase activity growing on 2-tridecanone as sole source of carbon. They catalyzed a Baeyer-Villiger type of oxidation and converted the alpha-ketol to 3(Z)-dodecendioic acid. 3(Z)-Dodecendioic acid was isolated from the incubation mixture and identified by comparison with an authentic reference compound. These findings offer both a physiological role for alpha-ketol fatty acids in plant lipid hydroperoxide metabolism and new insights into an alternative biosynthetic pathway leading to traumatic acid (2(E)-dodecendioic acid).


Asunto(s)
Proteínas Bacterianas/fisiología , Bacterias Aerobias Gramnegativas/enzimología , Oxidorreductasas Intramoleculares , Ácidos Linoleicos/metabolismo , Lipooxigenasa/metabolismo , Oxigenasas de Función Mixta/fisiología , Bacterias Aerobias Gramnegativas/crecimiento & desarrollo , Isomerasas/metabolismo , Ácido Linoleico , Oxidación-Reducción
13.
Am J Cardiol ; 77(9): 713-22, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8651122

RESUMEN

This community-based study assessed whether there were age, sex, or racial differences in response to amlodipine 5 to 10 mg once daily in patients with mild to moderate essential hypertension. This prospective, open-label trial had a 2-week placebo period, a 4-week upward drug titration/efficacy period, and a 12-week drug maintenance period. There were 1,084 evaluable patients (mean age 55.5 years; 65% men and 35% women; 79% white and 21% black; 75% <65 and 25% > or = 65 years old). At the end of the titration/efficacy phase, the mean +/- SD blood pressure (BP) decreased by -16.3 +/- 12.3/-12.5 +/- 5.9 mm Hg, (p < or = 0.0001). Amlodipine produced a goal BP response (sitting diastolic BP < or = 90 mm Hg, or a 10 mm Hg decrease) in 86.0% of patients overall. The BP response was greater in women (91.4%) than in men (83.0%, p < or = 0.001), and greater in those > or = 65 years old (91.5%) than in those < 65 years old (84.1%, p < or = 0.01); however, it was similar between whites and blacks (86.0% vs 85.9%, respectively, p = NS). The sex difference in BP response could not be fully explained by differences in age, weight, dose (mg/kg), race, baseline BP, or compliance, and there were no differences among women based on use of hormone replacement therapy. Amlodipine was well tolerated; mild to moderate edema was the most common adverse effect. Thus, amlodipine was effective and safe as once-a-day monotherapy in the treatment of mild to moderate hypertension in a community-based population. Women had a greater BP response to amlodipine.


Asunto(s)
Amlodipino/uso terapéutico , Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Amlodipino/administración & dosificación , Amlodipino/efectos adversos , Antihipertensivos/administración & dosificación , Antihipertensivos/efectos adversos , Población Negra , Presión Sanguínea/efectos de los fármacos , Peso Corporal , Tolerancia a Medicamentos , Edema/inducido químicamente , Terapia de Reemplazo de Estrógeno , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/sangre , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Placebos , Estudios Prospectivos , Factores Sexuales , Población Blanca
14.
J Cardiovasc Pharmacol ; 26(3): 471-6, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8583790

RESUMEN

As part of the Amlodipine Cardiovascular Community Trial (ACCT), which was a large multicenter study designed to assess the effects of the calcium channel blocker amlodipine besylate (Norvasc) as monotherapy for treatment of mild to moderate hypertension, we sought to determine the effects of amlodipine on regression of left ventricular (LV) hypertrophy (LVH). The study began with a 2-week placebo run-in period (baseline), before which antihypertensive drugs had been discontinued. Amlodipine was then administered at 5-10 mg/day during a 4-week titration/efficacy period. Patients achieving a goal diastolic blood pressure (DBP) of < or = 90 mm Hg or a decrease in DBP of > or = 10 mm Hg entered a 12-week maintenance phase and had the option to continue long-term therapy thereafter. Echocardiograms were obtained in a subset of patients at the end of the baseline period. In patients with LVH at baseline, echocardiograms were repeated at the end of 16 weeks of therapy (week 18), and at 42 weeks in patients continuing long-term therapy. Thirty-seven percent of 124 hypertensive patients screened for LVH at baseline had LVH detected on echocardiograms. Blacks had a higher incidence of LVH (64%) as compared with whites (34%, p < 0.05). Patients with LVH were more likely to have a higher baseline systolic BP (SBP) and DBP. Their sitting SBP and DBP decreased significantly from a mean of 163/102 mm Hg at baseline to 139/86 mm Hg with amlodipine therapy at week 18 (p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Amlodipino/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Ventrículos Cardíacos/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Población Negra , Presión Sanguínea/efectos de los fármacos , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/efectos de los fármacos , Población Blanca
15.
Am J Respir Cell Mol Biol ; 12(3): 315-9, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7532979

RESUMEN

Eosinophils (EOS) and neutrophils (PMN) display different patterns of accumulation during various inflammatory reactions. We hypothesized that EOS and PMN may differ in their ligands for P-selectin, and that these ligands may differ from those previously identified for E-selectin. Recombinant human P-selectin was immobilized on plastic surfaces and adhesion of 51Cr-labeled human EOS or PMN was compared. EOS and PMN adhered in a concentration-dependent fashion, with similar maximal net adhesion. Preincubation with a blocking P-selectin antibody inhibited adhesion of both cell types, whereas a non-blocking antibody did not. To determine if the counterligands were sialylated proteins, cells were treated with various glycosidases and proteases before testing adhesion. Neuraminidase treatment markedly inhibited binding of both cell types, while endo-beta-galactosidase had no significant effect. Pretreatment with several proteases reduced adhesion of both cell types, although they consistently caused a greater inhibition of PMN binding than EOS binding. To determine whether the P-selectin ligands were surface structures whose expression or function may be altered by cell activation, leukocytes were pretreated with various stimuli; only platelet-activating factor (PAF) treatment reduced the capacity of leukocytes to adhere to P-selectin. Thus, the counterligands for P-selectin on EOS and PMN are similar sialylated, protease-sensitive, endo-beta-galactosidase-resistant structures, whose function and/or expression is reduced following treatment with PAF. These characteristics are clearly different than those reported for EOS and PMN ligands for E-selectin, and suggest disparate roles for P-selectin and E-selectin during EOS and PMN recruitment during inflammatory responses in vivo.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Eosinófilos/metabolismo , Neutrófilos/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Adhesión Celular , Selectina E , Endopeptidasas/farmacología , Glicósido Hidrolasas/farmacología , Humanos , Técnicas In Vitro , Antígenos del Grupo Sanguíneo de Lewis , Oligosacáridos/metabolismo , Selectina-P , Antígeno Sialil Lewis X
16.
J Immunol ; 152(2): 774-82, 1994 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-7506734

RESUMEN

Both neutrophils and eosinophils have been shown to bind to the inducible endothelial cell adhesion molecule E-selectin. For neutrophils, one of the reported ligands for E-selectin is the sialylated Lewis X Ag (sLe(x)). To analyze the counterligands on eosinophils for E-selectin, adhesion assays were performed in which purified leukocytes were allowed to adhere to a soluble recombinant form of the molecule immobilized on plastic plates. Eosinophils, like neutrophils, bound to immobilized E-selectin, but significantly more neutrophils than eosinophils adhered in this assay. Consistent with the greater ability of neutrophils to bind E-selectin was the observation by flow cytometry that neutrophils expressed significant levels of sLe(x) and a sialylated dimeric form of the Le(x) Ag (sialyl-dimeric Le(x), or sialyl-stage-specific embryonic Ag-1, recognized by mAb FH6), whereas the expression of these epitopes on eosinophils was extremely low or undetectable. Expression was similar on eosinophils from allergic and nonallergic donors, and was not altered on eosinophils after induction of L-selectin shedding in vitro by treatment with platelet-activating factor. For both eosinophils and neutrophils, treatment with sialidase was associated with the complete elimination of sLe(x) and sialyl-dimeric Le(x) surface expression, and abolished leukocyte adhesion to E-selectin. Another glycosidase, endo-beta-galactosidase, which specifically cleaves the beta 1-4 galactose linkage to N-acetyl-glucosamine when it exists in an extended chain form such as that found in sialyl-dimeric Le(x), significantly inhibited eosinophil and neutrophil adhesion and expression of sialyl-dimeric Le(x). Such treatment also reduced sLe(x) expression on eosinophils, while having little effect on total neutrophil sLe(x) expression. For both eosinophils and neutrophils the sialylated ligand did not appear to be a glycoprotein because pretreatment of leukocytes with several proteases had no effect on adhesion to E-selectin or on expression of sLe(x) and sialyl-dimeric Le(x). These data suggest that eosinophils, like neutrophils, use sialylated, protease-resistant structures to bind to E-selectin, although the eosinophil expresses much lower levels of these structures on its surface. A major proportion of the sLe(x)-containing E-selectin ligand on the surface of eosinophils appears to be in the form of sialyl-dimeric Le(x), whereas this represents a minor proportion on the surface of neutrophils. Based on results using endo-beta-galactosidase, it appears that these cells may rely disproportionately upon the cell surface sialyl-dimeric Le(x) to bind to E-selectin.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Eosinófilos/metabolismo , Glicoconjugados/metabolismo , Neutrófilos/metabolismo , Anticuerpos Monoclonales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Secuencia de Carbohidratos , Adhesión Celular , Selectina E , Humanos , Antígeno Lewis X , Ligandos , Datos de Secuencia Molecular , Sialoglicoproteínas/metabolismo
18.
J Appl Gerontol ; 10(1): 71-87, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10113555

RESUMEN

This article examines the social impact of Medicaid policy on the elderly in long-term care and identifies a previously unrecognized problem produced by Medicaid in New York State. Recent fieldwork in proprietary nursing homes in New York City shows that this state's Medicaid system results in a selection hierarchy on admissions and within nursing homes not only in terms of sponsor of payment but also in value, based on residents' functional level. Specifically, New York State Medicaid's Resource Utilization Groups (RUGs II) system is responsible for a new and startling phenomenon in long-term health care of the elderly: the creation of "minihospitals" in lieu of traditional skilled nursing facilities. This problem indicates the complex ways in which reimbursement policy drives priorities in nursing homes and creates unintended negative outcomes. In light of this consideration, various policy alternatives to Medicaid that would improve the plight of the elderly in long-term care are suggested and evaluated.


Asunto(s)
Medicaid/organización & administración , Casas de Salud/normas , Calidad de la Atención de Salud/economía , Mecanismo de Reembolso , Actividades Cotidianas , Anciano , Grupos Diagnósticos Relacionados , Estudios de Evaluación como Asunto , Política de Salud , Humanos , Entrevistas como Asunto , Cuidados a Largo Plazo/clasificación , Ciudad de Nueva York , Estados Unidos
19.
JAMA ; 261(9): 1355, 1360, 1989 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-2915463
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