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1.
Mar Pollut Bull ; 83(1): 181-9, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24768263

RESUMEN

Four popular, recreational beaches in Miami, FL are Hobie Beach, Virginia Key Beach, Crandon Park Beach, and Bill Baggs Cape Florida State Park. While all of the beaches are within a few miles of each other in Biscayne Bay, they have greatly differing water qualities, as determined by the testing for fecal indicator bacteria performed by the Florida Department of Health. Using the geodesic theory of transport barriers, we identify Lagrangian Coherent Structures (LCSs) in each area. We show how these material curves, which shape circulation and mixing patterns, can be used to explain the incongruous states of the water at beaches that should be comparable. The LCSs are computed using a hydrodynamic model and verified through field experimentation at each beach.


Asunto(s)
Playas , Hidrodinámica , Movimientos del Agua , Calidad del Agua , Algoritmos , Bacterias , Heces/microbiología , Florida , Recreación , Abastecimiento de Agua
2.
FEBS Lett ; 490(3): 132-41, 2001 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-11223028

RESUMEN

In Metazoans a number of cellular functions are controlled by receptor tyrosine kinases (RTKs) during development and in postnatal life. The execution of these programs requires that signals of adequate strength are delivered for the appropriate time within precise spatial boundaries. Several RTK inhibitors have been identified in invertebrate and mammalian organisms. Because they are involved in tuning and termination of receptor signals, negative regulators of RTK activity fulfill a fundamental function in the control of receptor signaling.


Asunto(s)
Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Animales , Ciclo Celular , Retroalimentación , Isoenzimas/metabolismo , Ligandos , Fosfolipasa C gamma , Fosforilación , Fosfolipasas de Tipo C/metabolismo
3.
J Chem Ecol ; 27(2): 257-71, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14768814

RESUMEN

9,10-Dihydrophenanthrenes and phenanthrenes, mimics of natural compounds with strong antialgal activity, have been synthesized through cross-coupling by zerovalent Ni of 1-(2-iodo-5-methoxy)-phenylethanol or 2-iodo-5-methoxyacetophenone with iodoxylenes. The synthetic compounds had a hydroxyl or a methoxyl group at C-2 and two methyls in the C ring. Assays on the green alga Selenastrum capricornutum showed that all the compounds, except 2-methoxy-5,7-dimethylphenanthrene, caused strong inhibition of algal growth at 10(-4) M. 2-Hydroxy-7,8-dimethyl-9,10-dihydrophenanthrene and 2-methoxy-5,6-dimethylphenanthrene fully inhibited growth at 10(-5) M.


Asunto(s)
Chlorophyta/efectos de los fármacos , Magnoliopsida/química , Fenantrenos/síntesis química , Fenantrenos/farmacología , Chlorophyta/crecimiento & desarrollo , Imitación Molecular , Fenantrenos/química , Relación Estructura-Actividad
4.
Pathologica ; 93(6): 668-71, 2001 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-11785119

RESUMEN

Parosteal lipoma is a usually indolent, rare benign tumor, characterized by clinicopathological findings similar to those of the commonly occurring subcutaneous lipoma, except for its intimate relationship with the connective tissue of the subjacent periosteal region. Parosteal lipoma commonly affects the diaphysis of long bones of the upper and lower limbs. We report an exceedingly rare case of parosteal lipoma of the rib, which presented in a 59-year-old man experiencing previous multiple traumas in this site.


Asunto(s)
Neoplasias Óseas/patología , Lipoma/patología , Periostio/patología , Costillas/patología , Neoplasias Óseas/diagnóstico por imagen , Cartílago/patología , Transformación Celular Neoplásica , Humanos , Lipoma/diagnóstico por imagen , Masculino , Metaplasia , Persona de Mediana Edad , Periostio/diagnóstico por imagen , Radiografía , Costillas/diagnóstico por imagen , Costillas/lesiones , Cicatrización de Heridas
5.
Mol Cell Biol ; 20(20): 7735-50, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11003669

RESUMEN

The product of rat gene 33 was identified as an ErbB-2-interacting protein in a two-hybrid screen employing the ErbB-2 juxtamembrane and kinase domains as bait. This interaction was reproduced in vitro with a glutathione S-transferase fusion protein spanning positions 282 to 395 of the 459-residue gene 33 protein. Activation of ErbB-2 catalytic function was required for ErbB-2-gene 33 physical interaction in living cells, whereas ErbB-2 autophosphorylation was dispensable. Expression of gene 33 protein was absent in growth-arrested NIH 3T3 fibroblasts but was induced within 60 to 90 min of serum stimulation or activation of the ErbB-2 kinase and decreased sharply upon entry into S phase. New differentiation factor stimulation of mitogen-deprived mammary epithelial cells also caused accumulation of gene 33 protein, which could be found in a complex with ErbB-2. Overexpression of gene 33 protein in mouse fibroblasts inhibited (i) cell proliferation driven by ErbB-2 but not by serum, (ii) cell transformation induced by ErbB-2 but not by Ras or Src, and (iii) sustained activation of ERK 1 and 2 by ErbB-2 but not by serum. The gene 33 protein may convey inhibitory signals downstream to ErbB-2 by virtue of its association with SH3-containing proteins, including GRB-2, which was found to associate with gene 33 protein in living cells. These data indicate that the gene 33 protein is a feedback inhibitor of ErbB-2 mitogenic function and a suppressor of ErbB-2 oncogenic activity. We propose that the gene 33 protein be renamed with the acronym RALT (receptor-associated late transducer).


Asunto(s)
Proteínas Portadoras , Dominio Catalítico , Transformación Celular Neoplásica , Mitógenos/antagonistas & inhibidores , Proteínas/metabolismo , Receptor ErbB-2/antagonistas & inhibidores , Transducción de Señal , Células 3T3 , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Ciclo Celular , División Celular , Activación Enzimática , Regulación de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mitógenos/química , Mitógenos/metabolismo , Datos de Secuencia Molecular , Fosforilación , Unión Proteica , Proteínas/química , Proteínas/genética , Ratas , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Técnicas del Sistema de Dos Híbridos , Dominios Homologos src
6.
FEBS Lett ; 463(1-2): 83-6, 1999 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-10601643

RESUMEN

Apolipoprotein E (apo E) exerts a protective effect against atherosclerosis, related to its role in intracellular cholesterol removal and remnants clearance. In this study we investigated the effect of dietary and hypothyroid hypercholesterolemia, induced respectively by a high cholesterol diet and by propylthiouracil, on hepatic apo E expression in Wistar male rats. The Northern and Western blot analysis of hepatic mRNA and protein levels showed a 2-3-fold increase of apo E in hypercholesterolemic rats compared to controls. The incubation of FAO rat hepatoma cells with 25-OH cholesterol and mevalonate led to a three-fold increase of apo E mRNA, demonstrating a direct role of cholesterol on apo E expression. This effect was completely abolished by elevating intracellular cAMP levels with forskolin. Immunoblot and immunofluorescence analysis revealed that 25-OH cholesterol/mevalonate strongly increased also apo E protein synthesis and secretion in FAO cells. Our data demonstrate that hypercholesterolemia, apart of the cause (diet or hypothyroidism) induces liver apo E expression in the rat and that this effect can be directly related, via cAMP, to cholesterol.


Asunto(s)
Apolipoproteínas E/biosíntesis , Colesterol en la Dieta/metabolismo , Hipercolesterolemia/metabolismo , Hígado/metabolismo , Animales , Northern Blotting , Western Blotting , Membrana Celular/metabolismo , Densitometría , Hipercolesterolemia/inducido químicamente , Masculino , Microscopía Fluorescente , Propiltiouracilo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Células Tumorales Cultivadas
7.
Arch Dis Child ; 79(4): 306-11, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9875039

RESUMEN

The transition process for young physically disabled people (n = 87) was studied in three districts to determine how it varied between schools, and how it was perceived by the disabled and their carers. The experiences of the young people were compared with guidelines for good practice based on relevant legislation. Results showed that young disabled people experienced a poor handover to adult services if they had no "statement of special educational need" or if they went to further education college. Young people with cerebral palsy or complex multiple problems fared less well than those with spina bifida or juvenile chronic arthritis. There are several deficiencies in the legislation. Physically disabled young people should receive a transition review regardless of whether they have a "statement". The range of severity and type of disorders among the young physically disabled argues for a range of services--the category is too broad to be useful for research, service planning, and provision.


Asunto(s)
Niños con Discapacidad , Calidad de Vida , Adolescente , Adulto , Niño , Servicios de Salud del Niño/organización & administración , Servicios de Salud Comunitaria/organización & administración , Continuidad de la Atención al Paciente , Evaluación de la Discapacidad , Educación Especial , Femenino , Humanos , Masculino , Sistema de Registros
8.
Biochem Biophys Res Commun ; 215(3): 1088-95, 1995 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-7488035

RESUMEN

The cDNAs coding for the alpha and beta components of XrpFI, an activator of ribosomal protein genes transcription, were isolated. RNA analysis showed that transcripts of the beta genes are present at constant level throughout Xenopus development unlike the beta proteins which are undetectable in the early stages of embryogenesis when transcription is silent. On the contrary, alpha transcripts and proteins were found in all the embryo stages examined. The role of the XrpFI alpha and beta subunits in rp-gene transcription has been studied by mRNA microinjection into X.laevis oocytes. The presence of the beta subunit appears to be critical for the proper rp-gene promoter function.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Expresión Génica , Proteínas Nucleares/biosíntesis , Oocitos/metabolismo , Proteínas de Xenopus , Animales , Secuencia de Bases , Cloranfenicol O-Acetiltransferasa/biosíntesis , Clonación Molecular , Sondas de ADN , ADN Complementario , Proteínas de Unión al ADN/metabolismo , Embrión no Mamífero/fisiología , Femenino , Técnicas In Vitro , Sustancias Macromoleculares , Ratones , Microinyecciones , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Proteínas Recombinantes/biosíntesis , Transcripción Genética , Xenopus laevis , beta-Galactosidasa/biosíntesis
10.
J Biol Chem ; 269(40): 25172-7, 1994 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-7929206

RESUMEN

The protein sequence of cytotoxic T-lymphocyte antigen-2 beta (CTLA-2 beta) is 36% identical to the proregion of mouse cathepsin L (Denizot, F., Brunet, J.F., Roustan, P., Harper, K., Suzan, M., Luciani, M. F., Mattei, M. G., and Goldstein, P. (1989) Eur. J. Immunol. 19, 631-635). Here we report the expression, purification, and characterization of recombinant murine CTLA-2 beta. The protein was purified by consecutive gel-filtration, anion-exchange, and reverse-phase (C4) chromatography. Purified CTLA-2 beta exists in solution primarily as a dimer but also as a disulfide-linked tetramer as judged by size exclusion chromatography. Circular dichroism studies suggest that the dimeric form of the protein contains 8% alpha-helix, 67% beta-sheet, and 21% random coil and also indicates that there is a conformational change upon formation of the tetramer. The protein is a competitive inhibitor of certain cysteine proteases including papain (Ki = 25 nM), cathepsins L (Ki = 24 nM) and H (IC50 = 67 nM) but not cathepsin B. CTLA-2 beta forms a noncovalent complex with cathepsin L and has a stoichiometry of binding to papain of 1 mol of CTLA-2 beta/mol of papain. There is no homology between CTLA-2 beta and any of the known cysteine protease inhibitors, including the kininogens and cystatins. Therefore, CTLA-2 beta represents a novel class of cysteine protease inhibitor that is specific for the cathepsin L family of proteases.


Asunto(s)
Antígenos/aislamiento & purificación , Catepsinas/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/aislamiento & purificación , Endopeptidasas , Linfocitos T Citotóxicos/inmunología , Antígenos/química , Secuencia de Bases , Catepsina L , Catepsinas/química , Cromatografía en Gel , Cisteína Endopeptidasas , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/farmacología , Humanos , Datos de Secuencia Molecular , Peso Molecular
11.
J Exp Zool ; 262(3): 340-2, 1992 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-1322446

RESUMEN

At least two different receptor molecules have been described that are capable of binding tumor necrosis factor alpha, a cytokine that plays an important role in inflammation and antitumor activity. Comparative analyses at the nucleotide sequence level suggest that these receptors are members of a newly defined protein family that also includes human and rat nerve growth factor receptors. In this study, we determine the chromosome assignments of the human TNF alpha receptor genes, one of which may have evolved as part of a conserved Hox locus-containing chromosome segment.


Asunto(s)
Cromosomas Humanos Par 12 , Receptores de Superficie Celular/genética , Secuencia de Bases , Mapeo Cromosómico , Sondas de ADN , Humanos , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Receptores del Factor de Necrosis Tumoral
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