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1.
Mar Pollut Bull ; 83(1): 181-9, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24768263

RESUMO

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.


Assuntos
Praias , Hidrodinâmica , Movimentos da Água , Qualidade da Água , Algoritmos , Bactérias , Fezes/microbiologia , Florida , Recreação , Abastecimento de Água
2.
FEBS Lett ; 490(3): 132-41, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11223028

RESUMO

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.


Assuntos
Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Animais , Ciclo Celular , Retroalimentação , Isoenzimas/metabolismo , Ligantes , Fosfolipase C gama , Fosforilação , Fosfolipases Tipo C/metabolismo
3.
J Chem Ecol ; 27(2): 257-71, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14768814

RESUMO

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.


Assuntos
Clorófitas/efeitos dos fármacos , Magnoliopsida/química , Fenantrenos/síntese química , Fenantrenos/farmacologia , Clorófitas/crescimento & desenvolvimento , Mimetismo Molecular , Fenantrenos/química , Relação Estrutura-Atividade
4.
Pathologica ; 93(6): 668-71, 2001 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-11785119

RESUMO

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.


Assuntos
Neoplasias Ósseas/patologia , Lipoma/patologia , Periósteo/patologia , Costelas/patologia , Neoplasias Ósseas/diagnóstico por imagem , Cartilagem/patologia , Transformação Celular Neoplásica , Humanos , Lipoma/diagnóstico por imagem , Masculino , Metaplasia , Pessoa de Meia-Idade , Periósteo/diagnóstico por imagem , Radiografia , Costelas/diagnóstico por imagem , Costelas/lesões , Cicatrização
5.
Mol Cell Biol ; 20(20): 7735-50, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11003669

RESUMO

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).


Assuntos
Proteínas de Transporte , Domínio Catalítico , Transformação Celular Neoplásica , Mitógenos/antagonistas & inibidores , Proteínas/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Transdução de Sinais , Células 3T3 , Sequência de Aminoácidos , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Ciclo Celular , Divisão Celular , Ativação Enzimática , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mitógenos/química , Mitógenos/metabolismo , Dados de Sequência Molecular , Fosforilação , Ligação Proteica , Proteínas/química , Proteínas/genética , Ratos , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Domínios de Homologia de src
6.
FEBS Lett ; 463(1-2): 83-6, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10601643

RESUMO

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.


Assuntos
Apolipoproteínas E/biossíntese , Colesterol na Dieta/metabolismo , Hipercolesterolemia/metabolismo , Fígado/metabolismo , Animais , Northern Blotting , Western Blotting , Membrana Celular/metabolismo , Densitometria , Hipercolesterolemia/induzido quimicamente , Masculino , Microscopia de Fluorescência , Propiltiouracila , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Células Tumorais Cultivadas
7.
Arch Dis Child ; 79(4): 306-11, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9875039

RESUMO

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.


Assuntos
Crianças com Deficiência , Qualidade de Vida , Adolescente , Adulto , Criança , Serviços de Saúde da Criança/organização & administração , Serviços de Saúde Comunitária/organização & administração , Continuidade da Assistência ao Paciente , Avaliação da Deficiência , Educação Inclusiva , Feminino , Humanos , Masculino , Sistema de Registros
8.
Biochem Biophys Res Commun ; 215(3): 1088-95, 1995 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-7488035

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Expressão Gênica , Proteínas Nucleares/biossíntese , Oócitos/metabolismo , Proteínas de Xenopus , Animais , Sequência de Bases , Cloranfenicol O-Acetiltransferase/biossíntese , Clonagem Molecular , Sondas de DNA , DNA Complementar , Proteínas de Ligação a DNA/metabolismo , Embrião não Mamífero/fisiologia , Feminino , Técnicas In Vitro , Substâncias Macromoleculares , Camundongos , Microinjeções , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Proteínas Recombinantes/biossíntese , Transcrição Gênica , Xenopus laevis , beta-Galactosidase/biossíntese
10.
J Biol Chem ; 269(40): 25172-7, 1994 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-7929206

RESUMO

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.


Assuntos
Antígenos/isolamento & purificação , Catepsinas/antagonistas & inibidores , Inibidores de Cisteína Proteinase/isolamento & purificação , Endopeptidases , Linfócitos T Citotóxicos/imunologia , Antígenos/química , Sequência de Bases , Catepsina L , Catepsinas/química , Cromatografia em Gel , Cisteína Endopeptidases , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/farmacologia , Humanos , Dados de Sequência Molecular , Peso Molecular
11.
J Exp Zool ; 262(3): 340-2, 1992 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1322446

RESUMO

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.


Assuntos
Cromossomos Humanos Par 12 , Receptores de Superfície Celular/genética , Sequência de Bases , Mapeamento Cromossômico , Sondas de DNA , Humanos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Receptores do Fator de Necrose Tumoral
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