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1.
Gene Ther ; 18(7): 692-701, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21368903

RESUMO

Matrix metalloproteinases (MMPs) are a family of proteinases known to have a role in cell migration. In the present study, we evaluated the role of MMP-2 on tropism of human umbilical cord blood-derived stem cells (hUCBSCs) in a human medulloblastoma tumor model. Consequences of MMP-2 inhibition on stem cell tropism towards medulloblastoma were studied in terms of stem cell migration by using cell culture inserts, transwell chamber assay, western blotting for MMP-2 and migratory molecules, and immunohistochemistry. Conditioned medium from Daoy/D283 cells infected with adenoviral vector encoding MMP-2 small interfering RNA (siRNA) (Ad-MMP-2 si)-reduced stem cell migration as compared with conditioned medium from mock and scrambled vector (Ad-SV) infected cells. In addition, MMP-2 inhibition in the tumor cells decreased the expression of stromal cell-derived factor 1 (SDF1) in the tumor-conditioned medium, which results in impaired SDF1/CXCR4 signaling leading to decreased stem cell tropism towards the tumor cells. We further show that MMP-2 inhibition in the tumor cells repressed stem cell tropism towards medulloblastoma tumors in vivo. In summary, we conclude that hUCBSCs can integrate into human medulloblastoma after local delivery and that MMP-2 expression by the tumor cells mediates this response through the SDF1/CXCR4 axis.


Assuntos
Movimento Celular , Técnicas de Transferência de Genes , Metaloproteinase 2 da Matriz/genética , Meduloblastoma/terapia , Células-Tronco Mesenquimais , Animais , Linhagem Celular Tumoral , Quimiocina CXCL12/genética , Meios de Cultivo Condicionados , Sangue Fetal , Humanos , Metaloproteinase 2 da Matriz/farmacologia , Inibidores de Metaloproteinases de Matriz , Camundongos , Receptores CXCR4/genética , Técnicas de Cultura de Tecidos
2.
Cell Death Differ ; 17(10): 1529-39, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20339379

RESUMO

Medulloblastoma and neuroblastoma belong to a group of neoplasms designated as primitive neuroectodermal tumors (PNETs). Secreted protein, acidic and rich in cysteine (SPARC) is a matrix-associated glycoprotein that influences a variety of cellular activities in vitro and in vivo. In this study, we provide evidence that expression of SPARC cDNA induces autophagy in PNET cells followed by apoptotic cell death. SPARC-induced autophagy was morphologically characterized by (i) the formation of membrane-bound autophagic vacuoles (AVOs), (ii) increase in the levels of microtubule-associated protein light chain 3 (LC3) and (iii) induction of the lysososmal enzyme cathepsin B. Cathepsin B, in turn induced mitochondrial release of cytochrome c and activated caspase-3, events that signify the onset of apoptotic cell death. In agreement with these observations, inhibition of autophagy by 3-MA reduced AVO formation and LC3 and inhibited apoptosis, suggesting that autophagy has a role in SPARC-mediated apoptosis. Blocking cathepsin B expression with a specific inhibitor of cathepsin B suppressed apoptosis but did not affect autophagy, which suggests that cathepsin B is a molecular link between autophagy and apoptosis. In summary, these findings show that SPARC expression induces autophagy, which results in the elevation of cathepsin B and subsequent mitochondria-mediated apoptosis.


Assuntos
Apoptose , Autofagia , Catepsina B/metabolismo , Tumores Neuroectodérmicos Primitivos/metabolismo , Osteonectina/metabolismo , Animais , Caspase 3/metabolismo , Citocromos c/metabolismo , Humanos , Camundongos , Camundongos Nus , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Osteonectina/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Células Tumorais Cultivadas
3.
Br J Cancer ; 102(3): 530-40, 2010 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-20087345

RESUMO

BACKGROUND: Secreted protein acidic and rich in cysteine (SPARC), a matricellular glycoprotein, modulates cellular interaction with the extracellular matrix and is capable of altering the growth of various cancers. We therefore sought to determine the effect of SPARC expression on medulloblastoma tumour growth and angiogenesis. METHODS: To this extent, we selected three SPARC full-length cDNA overexpressed clones (Daoy-SP). Consequences of SPARC overexpression were studied in terms of cell growth, angiogenesis using co-culture assay in vitro, dorsal skin-fold chamber assay in vivo, PCR Array for human angiogenic genes, as well as western blotting for angiogenic molecules and tumour growth, in an orthotopic tumour model. RESULTS: The SPARC protein and mRNA levels were increased by approximately three-fold in Daoy-SP cells compared with parental (Daoy-P) and vector (Daoy-EV) controls. Daoy-SP clones reduced tumour cell-induced angiogenesis in vitro and in vivo, and formed small tumours with fewer blood vessels when compared with controls. Matrix metalloprotease-9 (MMP-9) and vascular endothelial growth factor (VEGF) expression were decreased in Daoy-SP clones. Further, inhibition of MMP-9 expression caused SPARC-mediated inhibition of angiogenesis and tumour growth as MMP-9 rescued SPARC-mediated anti-angiogenic effect in vitro and tumour growth inhibition in vivo. CONCLUSION: Overexpression of SPARC decreases angiogenesis, which leads to decreased tumour growth. Further, the role of MMP-9 could be attributed to the anti-angiogenic effect of SPARC.


Assuntos
Metaloproteinase 9 da Matriz/fisiologia , Neovascularização Patológica/prevenção & controle , Osteonectina/fisiologia , Animais , Linhagem Celular , Proliferação de Células , Feminino , Humanos , Metaloproteinase 9 da Matriz/análise , Meduloblastoma/irrigação sanguínea , Meduloblastoma/patologia , Camundongos , Osteonectina/análise , Fator A de Crescimento do Endotélio Vascular/análise
4.
Cochrane Database Syst Rev ; (1): CD006411, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18254103

RESUMO

BACKGROUND: The use of games as an educational strategy has the potential to improve health professionals' performance (e.g. adherence to standards of care) through improving their knowledge, skills and attitudes. OBJECTIVES: The objective was to assess the effect of educational games on health professionals' performance, knowledge, skills, attitude and satisfaction, and on patient outcomes. SEARCH STRATEGY: We used a comprehensive search strategy including an electronic search of the following databases: DARE, EPOC register, CENTRAL, MEDLINE, EMBASE, CINAHL, AMED, ERIC, and Dissertation Abstracts Online (search date: January 2007). We also screened the reference list of included studies and relevant reviews, contact authors of relevant papers and reviews, and searched ISI Web of Science for papers citing studies included in the review SELECTION CRITERIA: We included randomized controlled trials (RCT), controlled clinical trials (CCT), controlled before and after (CBA) and interrupted time-series analysis (ITS). Study participants were qualified health professionals or in postgraduate training. The intervention was an educational game with "a form of competitive activity or sport played according to rules". DATA COLLECTION AND ANALYSIS: Using a standardized data form we extracted data on methodological quality, participants, interventions and outcomes of interest that included patient outcomes, professional behaviour (process of care outcomes), and professional's knowledge, skills, attitude and satisfaction. MAIN RESULTS: The search strategy identified 1156 citations. Out of 55 potentially eligible citations, we included one RCT. The methodological quality was fair. The game, used as a reinforcement technique, was based on the television game show "Family Feud" and focused on infection control. The study did not assess any patient or process of care outcomes. The group that was randomized to the game had statistically higher scores on the knowledge test (P = 0.02). AUTHORS' CONCLUSIONS: The findings of this systematic review do not confirm nor refute the utility of games as a teaching strategy for health professionals. There is a need for additional high-quality research to explore the impact of educational games on patient and performance outcomes.


Assuntos
Jogos Experimentais , Pessoal de Saúde , Resolução de Problemas , Competência Profissional , Atitude do Pessoal de Saúde , Comportamento Competitivo , Humanos , Satisfação no Emprego , Retenção Psicológica
5.
Int J Psychiatr Nurs Res ; 12(3): 1497-502, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17682590

RESUMO

BACKGROUND: Learning in general can be been a passive process. This review is aimed at evaluating the effectiveness of educational games as a teaching strategy in mental health professionals. METHODS: We searched for all relevant randomised control trials (RCT) that compared educational games as teaching strategies with other methods of learning using electronic and reference searching, and by contacting trial authors. Data were extracted from selected trials and, individual person data was analysed using fixed effect Peto Odds Ratio (OR) and the 95% confidence intervals (CI). If appropriate, the number needed to treat (NNT) or number needed to harm (NNH) was estimated. For continuous data, we calculated weighted mean differences. RESULTS: We identified one trial (n = 34) of an educational game for mental health nursing students which followed up participants only over a few hours. For an outcome we arbitrarily defined ('no academically important improvement [a 10% improvement in scores]'), those allocated to educational games fared considerably better than students in the standard education techniques group (OR 0.06 CI 0.01 to 0.27, NNT 3 CI 2 to 4). On average those in the games group scored six more points than the control students on a test of questions relevant to psychosis set to the standard of the mental health nursing curriculum of the day (WMD 6 CI 2.63 to 9.37). CONCLUSION: Current limited evidence suggests educational games could help mental health students gain more points in their tests; however this interesting study should be refined and repeated.


Assuntos
Educação em Enfermagem/organização & administração , Serviços de Saúde Mental , Enfermagem Psiquiátrica/educação , Ensino/métodos , Jogos de Vídeo , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Oncogene ; 26(55): 7675-83, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-17599056

RESUMO

We have previously reported that the downregulation of MMP-2 by adenovirus-mediated delivery of MMP-2 siRNA (Ad-MMP-2) reduced spheroid invasion and angiogenesis in vitro, and, metastasis and tumor growth in vivo. In this study, we investigated the mechanism of Ad-MMP-2-mediated growth inhibition in vitro and in vivo. Ad-MMP-2 infection led to the induction of apoptosis as determined by TUNEL assay, Annexin-V staining and PARP-1 cleavage in a dose-dependent manner in A549 cells. Ad-MMP-2 decreased the content of the antiapoptotic members of the Bcl-2 family proteins (Bcl-2 and Bcl-xL) and increased the content of the pro-apoptotic members of the Bcl-2 family (Bax and Bcl-xS) as determined by immunoblotting analysis. Furthermore, Ad-MMP-2-mediated apoptosis was accompanied by increase in truncated Bid, release of cytochrome c and the activation of caspase-8, -9 and -3. Immunoblot analysis showed that Ad-MMP-2 infection caused upregulation of Fas/Fas-L and FADD, and Anti-Fas-L antibody reversed Ad-MMP-2-induced apoptosis. Tissue inhibitor of metalloproteinases (TIMP)-3, an endogenous inhibitor of MMP-2, which cleaves Fas-L and activates the Fas/Fas-L inducing apoptotic pathway, was increased in Ad-MMP-2-treated cells. Adenovirus-mediated expression of MMP-2 siRNA in human lung xenografts in vivo resulted in increased immunostaining of Fas, Fas-L, cleaved Bid and TIMP-3. This is the first report, to our knowledge, showing that MMP-2 inhibition upregulates TIMP-3 levels, which in turn, promotes apoptosis in lung cancer.


Assuntos
Adenocarcinoma/enzimologia , Apoptose , Neoplasias Pulmonares/enzimologia , Inibidores de Metaloproteinases de Matriz , Receptor fas/metabolismo , Adenoviridae/genética , Animais , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Proteína Ligante Fas/análise , Proteína de Domínio de Morte Associada a Fas/metabolismo , Humanos , Metaloproteinase 2 da Matriz/genética , Camundongos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/genética , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Proteína X Associada a bcl-2/metabolismo , Receptor fas/análise
7.
Cochrane Database Syst Rev ; (3): CD000205, 2006 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-16855954

RESUMO

BACKGROUND: Tardive dyskinesia (TD) is a disfiguring movement disorder, often of the orofacial region, frequently caused by the use of neuroleptic drugs. A wide range of strategies have been used to help manage tardive dyskinesia, and for those who are unable to have their antipsychotic medication stopped or substantially changed, the benzodiazepine group of drugs have been suggested as a useful adjunctive treatment. OBJECTIVES: To determine the effects of benzodiazepines for neuroleptic-induced tardive dyskinesia in people with schizophrenia or other chronic mental illnesses. SEARCH STRATEGY: 1. Electronic searches. For the update of 2006, we searched The Cochrane Schizophrenia Group Trials Register (November 2005). For the previous two updates (1996, 2002) the review authors searched Biological Abstracts (1982-2002), the Cochrane Schizophrenia Group's Register of trials (February 2002), EMBASE (1980-2002), LILACS (1982-2002), MEDLINE (1966-2002), PsycLIT (1974-2002), SCISEARCH (2002), hand searched references of all included/excluded studies and contacted the first author of each included trial. SELECTION CRITERIA: We included all randomised clinical studies focusing on people with schizophrenia (or other chronic mental illnesses) and neuroleptic-induced tardive dyskinesia that compared benzodiazepines with placebo or no intervention. DATA COLLECTION AND ANALYSIS: We independently extracted data from the studies and ensured that they were reliably selected, and quality assessed. For homogenous dichotomous data we calculated random effects, relative risk (RR), 95% confidence intervals (CI) and, where appropriate, numbers needed to treat (NNT) on an intention-to-treat basis. We synthesised continuous data from valid scales by using a weighted mean difference (WMD). For continuous outcomes we preferred endpoint data to change data. MAIN RESULTS: We identified three trials (total N=56, one additional trial since 2002, n=24). Using benzodiazepines as an adjunctive treatment did not result in any clear changes for a series of tardive dyskinesia medium-term outcomes (n=30, 2 RCTs, RR not improved to clinically important extent 1.08 CI 0.57 to 2.05). One trial (n=24) found end point abnormal movement scores to be better for those receiving adjunct benzodiazepines(WMD AIMS -3.22 CI -4.63 to -1.81 ). Less than 10% in both groups left these studies before completion and none of the studies reported clear adverse effects. AUTHORS' CONCLUSIONS: One small study reports some preliminary evidence that benzodiazepines may have some effect in neuroleptic induced tardive dyskinesia. Inconclusive results from other studies means routine clinical use is not indicated and these treatments remain experimental.


Assuntos
Ansiolíticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Discinesia Induzida por Medicamentos/tratamento farmacológico , Moduladores GABAérgicos/uso terapêutico , Antipsicóticos/efeitos adversos , Discinesia Induzida por Medicamentos/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Cochrane Database Syst Rev ; (2): CD001471, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16625545

RESUMO

BACKGROUND: In traditional didactic teaching, the learner has a passive role, digesting the knowledge presented by the teacher. Stimulating and active teaching processes may be better at instilling information than more pedestrian approaches. Games involving repetition, reinforcement, association and use of multiple senses have been proposed as part of experiential learning. OBJECTIVES: To assess the effects of educational games on the knowledge and clinical skill of mental health professionals compared to the effects of standard teaching approaches. SEARCH STRATEGY: We performed electronic searches of AMED (1998 - November 2005), British Nursing Index (November 2005), Cochrane Library (Issue 3, 2005), Cochrane Schizophrenia Group Trials Register (November 2005), CINAHL (November 2005) EMBASE (November 2005), Educational Resources Information Centre on CSA (1966 - November 2005), MEDLINE (November 2005), PsycINFO (November 2005). We also searched references of all selected articles and contacted authors of included trials for more information. SELECTION CRITERIA: Randomised controlled trials comparing any educational game aiming at increasing knowledge and/or skills with a standard educational approach for mental health professionals. DATA COLLECTION AND ANALYSIS: We extracted data independently and analysed on an intention-to-treat basis. We analysed the individual person data using fixed effect Peto Odds Ratio (OR) calculated the 95% confidence intervals (CI). If appropriate, the number needed to treat (NNT) or number needed to harm (NNH) was estimated. For continuous data, we calculated weighted mean differences. MAIN RESULTS: We identified one trial (n=34) of an educational game for mental health nursing students of only a few hours follow up. For an outcome we arbitrarily defined ('no academically important improvement [a 10% improvement in scores]') those allocated to educational games fared considerably better than students in the standard education techniques group (OR 0.06 CI 0.01 to 0.27, NNT 3 CI 2 to 4). On average those in the games group scored six more points than the control students on a test of questions relevant to psychosis set to the standard of the mental health nursing curriculum of the day (WMD 6 CI 2.63 to 9.37). AUTHORS' CONCLUSIONS: Current limited evidence suggests educational games could help mental health students gain more points in their tests, especially if they have left revision to the last minute. This salient study should be refined and repeated.


Assuntos
Jogos Experimentais , Saúde Mental , Ensino/métodos , Humanos , Aprendizagem Baseada em Problemas/métodos
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