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1.
Emerg Med Int ; 2014: 203747, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24624300

RESUMO

Background. To identify, upon emergency department (ED) admission, predictors of unexpected death or unplanned intensive care/high dependency units (ICU/HDU) admission during the first 15 days of hospitalization on regular wards. Methods. Prospective cohort study in a medical-surgical adult ED in a teaching hospital, including consecutive patients hospitalized on regular wards after ED visit, and identification of predictors by logistic regression and Cox proportional hazards model. Results. Among 4,619 included patients, 77 (1.67%) target events were observed: 32 unexpected deaths and 45 unplanned transfers to an ICU/HDU. We identified 9 predictors of the target event including the oxygen administration on the ED, unknown current medications, and use of psychoactive drug(s). All predictors put the patients at risk during the first 15 days of hospitalization. A logistic model for hospital mortality prediction (death of all causes) still comprised oxygen administration on the ED, unknown current medications, and the use of psychoactive drug(s) as risk factors. Conclusion. The "use of oxygen therapy on the ED," the "current use of psychoactive drug(s)", and the "lack of knowledge of current medications taken by the patients" were important predisposing factors to severe adverse events during the 15 days of hospitalization on regular wards following the ED visit.

2.
PLoS One ; 8(1): e52915, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23326364

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs) are members of the metzincin superfamily of proteinases that cleave structural elements of the extracellular matrix and many molecules involved in signal transduction. Although there is evidence that MMPs promote the proper development of retinotectal projections, the nature and working mechanisms of specific MMPs in retinal development remain to be elucidated. Here, we report a role for zebrafish Mmp14a, one of the two zebrafish paralogs of human MMP14, in retinal neurogenesis and retinotectal development. RESULTS: Whole mount in situ hybridization and immunohistochemical stainings for Mmp14a in developing zebrafish embryos reveal expression in the optic tectum, in the optic nerve and in defined retinal cell populations, including retinal ganglion cells (RGCs). Furthermore, Mmp14a loss-of-function results in perturbed retinoblast cell cycle kinetics and consequently, in a delayed retinal neurogenesis, differentiation and lamination. These Mmp14a-dependent retinal defects lead to microphthalmia and a significantly reduced innervation of the optic tectum (OT) by RGC axons. Mmp14b, on the contrary, does not appear to alter retinal neurogenesis or OT innervation. As mammalian MMP14 is known to act as an efficient MMP2-activator, we also explored and found a functional link and a possible co-involvement of Mmp2 and Mmp14a in zebrafish retinotectal development. CONCLUSION: Both the Mmp14a expression in the developing visual system and the Mmp14a loss-of-function phenotype illustrate a critical role for Mmp14a activity in retinal and retinotectal development.


Assuntos
Embrião não Mamífero/metabolismo , Metaloproteinase 14 da Matriz/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Isoenzimas/genética , Isoenzimas/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Microftalmia/embriologia , Microftalmia/genética , Microftalmia/metabolismo , Microscopia Confocal , Neurogênese/genética , Lobo Óptico de Animais não Mamíferos/citologia , Lobo Óptico de Animais não Mamíferos/embriologia , Lobo Óptico de Animais não Mamíferos/metabolismo , Ligação Proteica , Retina/embriologia , Retina/metabolismo , Células Ganglionares da Retina/metabolismo , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/metabolismo
3.
Mol Neurobiol ; 45(1): 17-29, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22108898

RESUMO

Cell-cell and cell-matrix interactions are necessary for neuronal patterning and brain wiring during development. Matrix metalloproteinases (MMPs) are proteolytic enzymes capable of remodelling the pericellular environment and regulating signaling pathways through cleavage of a large degradome. MMPs have been suggested to affect cerebellar development, but the specific role of different MMPs in cerebellar morphogenesis remains unclear. Here, we report a role for MMP-3 in the histogenesis of the mouse cerebellar cortex. MMP-3 expression peaks during the second week of postnatal cerebellar development and is most prominently observed in Purkinje cells (PCs). In MMP-3 deficient (MMP-3(-/-)) mice, a protracted granule cell (GC) tangential migration and a delayed GC radial migration results in a thicker and persistent external granular layer, a retarded arrival of GCs in the inner granular layer, and a delayed GABAergic interneuron migration. Importantly, these neuronal migration anomalies, as well as the consequent disturbed synaptogenesis on PCs, seem to be caused by an abnormal PC dendritogenesis, which results in reduced PC dendritic trees in the adult cerebellum. Of note, these developmental and adult cerebellar defects might contribute to the aberrant motor phenotype observed in MMP-3(-/-) mice and suggest an involvement of MMP-3 in mouse cerebellar development.


Assuntos
Cerebelo/anormalidades , Metaloproteinase 3 da Matriz/deficiência , Metaloproteinase 3 da Matriz/genética , Malformações do Sistema Nervoso/enzimologia , Malformações do Sistema Nervoso/genética , Animais , Animais Recém-Nascidos , Padronização Corporal/genética , Cerebelo/crescimento & desenvolvimento , Cerebelo/fisiopatologia , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Atividade Motora/genética , Malformações do Sistema Nervoso/fisiopatologia , Fenótipo
4.
Mol Cancer ; 9: 30, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20132547

RESUMO

BACKGROUND: Factors responsible for invasive and metastatic progression of prostate cancer (PCa) remain largely unknown. Previously, we reported cloning of prosaposin (PSAP) and its genomic amplification and/or overexpression in several androgen-independent metastatic PCa cell lines and lymph node metastases. PSAP is the lysosomal precursor of saposins, which serve as activators for lysosomal hydrolases involved in the degradation of ceramide (Cer) and other sphingolipids. RESULTS: Our current data show that, in metastatic PCa cells, stable down-modulation of PSAP by RNA-interference via a lysosomal proteolysis-dependent pathway decreased beta1A-integrin expression, its cell-surface clustering, and adhesion to basement membrane proteins; led to disassembly of focal adhesion complex; and decreased phosphorylative activity of focal adhesion kinase and its downstream adaptor molecule, paxillin. Cathepsin D (CathD) expression and proteolytic activity, migration, and invasion were also significantly decreased in PSAP knock-down cells. Transient-transfection studies with beta1A integrin- or CathD-siRNA oligos confirmed the cause and effect relationship between PSAP and CathD or PSAP and Cer-beta1A integrin, regulating PCa cell migration and invasion. CONCLUSION: Our findings suggest that by a coordinated regulation of Cer levels, CathD and beta1A-integrin expression, and attenuation of "inside-out" integrin-signaling pathway, PSAP is involved in PCa invasion and therefore might be used as a molecular target for PCa therapy.


Assuntos
Movimento Celular , Regulação para Baixo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Saposinas/metabolismo , Membrana Basal/metabolismo , Catepsina D/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Ceramidas/metabolismo , Ativação Enzimática , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Adesões Focais/enzimologia , Inativação Gênica , Humanos , Integrina beta1/metabolismo , Masculino , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/enzimologia , Processamento de Proteína Pós-Traducional
5.
Prostate ; 67(2): 178-89, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17044040

RESUMO

BACKGROUND: Prosaposin overexpression and/or genomic amplification have been demonstrated in androgen-independent (AI) prostate cancer cell lines and tissues. Here, we explored the possibility for a functional relationship between prosaposin and androgen receptor (AR) in LNCaP cells. METHODS: The effect of prosaposin or its active molecular derivatives (e.g., saposin C) on expression and activity of androgen receptor (AR) and prostate-specific antigen (PSA) was examined by using immunoblotting, RT-PCR, transfection, and reporter gene assays, immunofluorescence staining, and inhibitors of signal transduction pathways. RESULTS: Prosaposin or saposin C, in an AI-manner, (a) increased AR mRNA and protein expression and nuclear AR content and its phosphorylation state; (b) increased PSA mRNA and protein expression; and (c) upregulated PSA- and an androgen-inducible probasin (PB)-reporter gene activity in LNCaP and AR-transfected PC-3 cells. Induction of PSA expression and reporter activity was substantially blocked or prevented with the antiandrogen bicalutamide, pertussis toxin, or inhibitors of MAPK- and PI3K/Akt-signaling pathways, indicating an androgen-agonistic effect for saposin C that involves AR and multiple signaling pathways. CONCLUSIONS: The results for the first time introduce prosaposin as an androgen-agonist in prostate cancer cells. This finding, together with the growth-promoting effect and overexpression of prosaposin, may support a growth advantage to AI prostate cancer cells.


Assuntos
Antígeno Prostático Específico/genética , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/genética , Saposinas/farmacologia , Antagonistas de Androgênios/farmacologia , Proteína de Ligação a Androgênios/genética , Proteína de Ligação a Androgênios/metabolismo , Anilidas/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Técnica Indireta de Fluorescência para Anticorpo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Humanos , Masculino , Nitrilas , Plasmídeos , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Compostos de Tosil , Transfecção , Regulação para Cima/efeitos dos fármacos
6.
Int J Biochem Cell Biol ; 38(10): 1729-40, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16807059

RESUMO

The low density lipoprotein receptor-related protein (LRP), a large scavenger receptor reported to mediate the uptake and degradation of various ligands, emerges as a promising receptor for targeting the invasive behaviour of human cancer cells. However, the accurate function of LRP during tumor invasion seems to be highly dependent on cellular context and remains controversial. The expression patterns of both this receptor and the main proteolytic systems involved in cell invasion were examined in two follicular thyroid carcinoma cell lines exhibiting different invasive phenotypes. We established that a low expression of LRP at the cell surface was associated to elevated extracellular MMP2 and urokinase plasminogen activator (uPA) activities as well as to high invasiveness properties. Surprisingly, neither exogenously added receptor-associated protein, an antagonist of LRP, nor LRP blocking antibodies significantly modified the amount of extracellular MMP2. Furthermore, the invasive phenotype of thyroid carcinoma cells was not related to their matrix metalloproteinases amount since different specific inhibitors of these proteases failed to affect the invasive properties of both cell lines. Additionally, blocking LRP-mediated clearance led to a further increase of the uPA amount and activities and to increased invasiveness in both cell lines. Finally thyroid carcinoma cells aggressiveness was widely increased by exogenous uPA; and anti-uPA antibodies treatments abolished both basal and receptor-associated protein-induced thyroid cell invasion. Overall our results identified the LRP-mediated clearance of uPA as one of the mechanisms involved during the control of human thyroid carcinoma cell invasion.


Assuntos
Carcinoma/patologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Neoplasias da Glândula Tireoide/patologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Anticorpos/farmacologia , Carcinoma/enzimologia , Linhagem Celular Tumoral , Membrana Celular/química , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/análise , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/antagonistas & inibidores , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Neoplasias da Glândula Tireoide/enzimologia
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