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1.
Braz. j. med. biol. res ; 51(2): e6520, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889032

RESUMO

Multiple growth factors can be administered to mimic the natural process of bone healing in bone tissue engineering. We investigated the effects of sequential release of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) from polylactide-poly (ethylene glycol)-polylactide (PELA) microcapsule-based scaffolds on bone regeneration. To improve the double emulsion/solvent evaporation technique, VEGF was encapsulated in PELA microcapsules, to which BMP-2 was attached. The scaffold (BMP-2/PELA/VEGF) was then fused to these microcapsules using the dichloromethane vapor method. The bioactivity of the released BMP-2 and VEGF was then quantified in rat mesenchymal stem cells (rMSCs). Immunoblotting analysis showed that BMP-2/PELA/VEG promoted the differentiation of rMSCs into osteoblasts via the MAPK and Wnt pathways. Osteoblast differentiation was assessed through alkaline phosphatase expression. When compared with simple BMP-2 plus VEGF group and pure PELA group, osteoblast differentiation in BMP-2/PELA/VEGF group significantly increased. An MTT assay indicated that BMP-2-loaded PELA scaffolds had no adverse effects on cell activity. BMP-2/PELA/VEG promoted the differentiation of rMSCs into osteoblast via the ERK1/2 and Wnt pathways. Our findings indicate that the sequential release of BMP-2 and VEGF from PELA microcapsule-based scaffolds is a promising approach for the treatment of bone defects.


Assuntos
Animais , Coelhos , Ratos , Poliésteres/farmacologia , Polietilenoglicóis/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Alicerces Teciduais , Proteína Morfogenética Óssea 2/metabolismo , Células-Tronco Mesenquimais/citologia , Fatores de Tempo , Regeneração Óssea , Transdução de Sinais/fisiologia , Células Cultivadas , Modelos Animais , Proliferação de Células , beta Catenina/fisiologia , Nanopartículas , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt/fisiologia
2.
Braz. j. med. biol. res ; 51(4): e6651, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889066

RESUMO

The aim of this study was to evaluate the clinical and radiographic outcomes of upper thoracic (UT) versus lower thoracic (LT) upper instrumented vertebrae (UIV) for adult scoliosis by meta-analysis. We conducted a literature search in three databases to retrieve related studies up to March 15, 2017. The preliminary screened studies were assessed by two reviewers according to the selection criteria. All analyses were carried out using the statistical software package R version 2.31. Odds ratios (OR) with 95% confidence intervals (CI) were used to describe the results. The I2 statistic and Q statistic test were used for heterogeneity assessment. Egger's test was performed to detect publication bias. To assess the effect of each study on the overall pooled OR or standardized mean difference (SMD), sensitive analysis was conducted. Ten trials published between 2007 and 2015 were eligible and included in our study. Meta-analysis revealed that the UT group was associated with more blood loss (SMD=0.4779, 95%CI=0.3349-0.6209, Z=6.55, P<0.0001) and longer operating time (SMD=0.5780, 95%CI=0.1971-0.958, Z=2.97, P=0.0029) than the LT group. However, there was no significant difference in Oswestry Disability Index, Scoliosis Research Society (SRS) function subscores, radiographic outcomes including sagittal vertical axis, lumbar lordosis, and thoracic kyphosis, length of hospital stay, and revision rates between the two groups. No evidence of publication bias was found between the two groups. Fusion from the lower thoracic spine (below T10) has as advantages a shorter operation time and less blood loss than upper thoracic spine (above T10) in posterior long-segment fixation for degenerative lumbar scoliosis.


Assuntos
Humanos , Adulto , Vértebras Lombares/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Fusão Vertebral/instrumentação , Vértebras Torácicas/diagnóstico por imagem , Medicina Baseada em Evidências , Seguimentos , Viés de Publicação , Estudos Retrospectivos
3.
Braz. j. med. biol. res ; 50(1): e5794, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-839241

RESUMO

Propofol is a frequently used intravenous anesthetic agent. Recent studies show that propofol exerts a number of non-anesthetic effects. The present study aimed to investigate the effects of propofol on lung cancer cell lines H1299 and H1792 and functional role of microRNA (miR)-486 in these effects. H1299 and/or H1792 cells were treated with or without propofol and transfected or not with miR-486 inhibitor, and then cell viability and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry. The expression of miR-486 was determined by quantitative real-time polymerase chain reaction (qRT-PCR) with or without propofol treatment. Western blot was performed to analyze the protein expression of Forkhead box, class O (FOXO) 1 and 3, Bcl-2 interacting mediator of cell death (Bim), and pro- and activated caspases-3. Results showed that propofol significantly increased the miR-486 levels in both H1299 and H1792 cells compared to untreated cells in a dose-dependent manner (P<0.05 or P<0.01). Propofol statistically decreased cell viability but increased the percentages of apoptotic cells and protein expressions of FOXO1, FOXO3, Bim, and pro- and activated caspases-3; however, miR-486 inhibitor reversed the effects of propofol on cell viability, apoptosis, and protein expression (P<0.05 or P<0.01). In conclusion, propofol might be an ideal anesthetic for lung cancer surgery by effectively inhibiting lung cancer cell viability and inducing cell apoptosis. Modulation of miR-486 might contribute to the anti-tumor activity of propofol.


Assuntos
Humanos , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Propofol/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real
4.
Artigo em Inglês | IMSEAR | ID: sea-168146

RESUMO

Lectin-like oxidized LDL receptor-1 (LOX-1), a lectin-like 50-kD receptor for oxidized low-density lipoproteins (ox-LDL), is present primarily on endothelial cells. Oxidatively modified low-density lipoprotein (oxLDL) is implicated in the pathogenesis of atherosclerosis. Endothelial dysfunction is the initial change in the vascular wall that induces morphological changes for atheroma-formation. LOX-1 was identified as the receptor for oxLDL that was thought to be a major cause of endothelial dysfunction. LOX-1 has been demonstrated to contribute not only to endothelial dysfunction, but also to atherosclerotic-plaque formation, hypertension, myocardial infarction and intimal thickening after balloon injury. Studies with transgenic and knockout mouse models have elucidated in part the role of LOX-1 in the pathogenesis of atherosclerosis and cardiac remodeling. Recently, a circulating soluble form of LOX-1(sLOx-1), corresponding solely to its extracellular domain, has been identified in human serum. Circulating levels of sLOX-1 are increased in inflammatory and atherosclerotic conditions and are associated with acute coronary syndrome, with the severity of coronary artery disease, and with serum biomarkers for oxidative stress and inflammation, suggesting that they could be useful marker for vascular injury. Identification and regulation of this receptor and understanding of signal transduction pathways might open new gateways from diagnosis to therapeutics for cardiovascular diseases.

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