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1.
Hum Mol Genet ; 30(1): 46-64, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33438023

RESUMO

Glioblastoma (GB) is the most frequent and malignant type of brain tumor, for which no effective therapy exists. The high proliferative and invasive nature of GB, as well as its acquired resistance to chemotherapy, makes this type of cancer extremely lethal shortly after diagnosis. Long non-protein coding RNAs (lncRNA) are a class of regulatory RNAs whose levels can be dysregulated in the context of diseases, unbalancing several physiological processes. The lncRNA associated with microvascular invasion in hepatocellular carcinoma (lncRNA-MVIH), overexpressed in several cancers, was described to co-precipitate with phosphoglycerate kinase 1 (PGK1), preventing secretion of this enzyme to the extracellular environment and promoting cell migration and invasion. We hypothesized that, by silencing the expression of lncRNA-MVIH, the secretion of PGK1 would increase, reducing GB cell migration and invasion capabilities. We observed that lncRNA-MVIH silencing in human GB cells significantly decreased glycolysis, cell growth, migration, and invasion and sensitized GB cells to cediranib. However, no increase in extracellular PGK1 was observed as a consequence of lncRNA-MVIH silencing, and therefore, we investigated the possibility of a mechanism of miRNA sponge of lncRNA-MVIH being in place. We found that the levels of miR-302a loaded onto RISC increased in GB cells after lncRNA-MVIH silencing, with the consequent downregulation of several miR-302a molecular targets. Our findings suggest a new mechanism of action of lncRNA-MVIH as a sponge of miR-302a. We suggest that lncRNA-MVIH knockdown may be a promising strategy to address GB invasiveness and chemoresistance, holding potential towards its future application in a clinical context.


Assuntos
Glioblastoma/genética , MicroRNAs/genética , Fosfoglicerato Quinase/genética , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/patologia , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
2.
Hum Mol Genet ; 30(23): 2315-2331, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34245265

RESUMO

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor characterized by fast proliferation, high invasion and resistance to current standard treatment. The average survival rate post-diagnosis is 14.6 months, despite the aggressive standard post-surgery radiotherapy concomitant with chemotherapy with temozolomide (TMZ). Currently, efforts are being endowed to develop new and more efficient therapeutic approaches capable to overcome chemoresistance, inhibit tumor progression and improve overall patient survival rate. Abnormal microRNA (miRNA) expression has been correlated with chemoresistance, proliferation and resistance to apoptosis, which result from their master regulatory role of gene expression. Altered cell metabolism, favoring glycolysis, was identified as an emerging cancer hallmark and has been described in GB, thus offering a new target for innovative GB therapies. In this work, we hypothesized that a gene therapy-based strategy consisting of the overexpression of a miRNA downregulated in GB and predicted to target crucial metabolic enzymes might promote a shift of GB cell metabolism, decreasing the glycolytic dependence of tumor cells and contributing to their sensitization to chemotherapy with TMZ. The increase of miR-200c levels in DBTRG cells resulted in downregulation of messenger RNA of enzymes involved in bioenergetics pathways and impaired cell metabolism and mobility. In addition, miR-200c overexpression prior to DBTRG cell exposure to TMZ resulted in cell cycle arrest. Overall, our results show that miR-200c overexpression could offer a way to overcome chemoresistance developed by GB cells in response to current standard chemotherapy, providing an improvement to current GB standard treatment, with benefit for patient outcome.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Metabolismo Energético , Glioblastoma/genética , Glioblastoma/metabolismo , MicroRNAs/genética , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Interferência de RNA , RNA Mensageiro
3.
Hum Mol Genet ; 28(16): 2738-2751, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31087038

RESUMO

Glioblastoma (GB) is the most aggressive and common form of primary brain tumor, characterized by fast proliferation, high invasion, and resistance to current standard treatment. The average survival rate post-diagnosis is only of 14.6 months, despite the aggressive standard post-surgery treatment approaches of radiotherapy concomitant with chemotherapy with temozolomide. Altered cell metabolism has been identified as an emerging cancer hallmark, including in GB, thus offering a new target for cancer therapies. On the other hand, abnormal expression levels of miRNAs, key regulators of multiple molecular pathways, have been correlated with pathological manifestations of cancer, such as chemoresistance, proliferation, and resistance to apoptosis. In this work, we hypothesized that gene therapy based on modulation of a miRNA with aberrant expression in GB and predicted to target crucial metabolic enzymes might impair tumor cell metabolism. We found that the increase of miR-144 levels, shown to be downregulated in U87 and DBTRG human GB cell lines, as well as in GB tumor samples, promoted the downregulation of mRNA of enzymes involved in bioenergetic pathways, with consequent alterations in cell metabolism, impairment of migratory capacity, and sensitization of DBTRG cells to a chemotherapeutic drug, the dichloroacetate (DCA). Taken together, our findings provide evidence that the miR-144 plus DCA combined therapy holds promise to overcome GB-acquired chemoresistance, therefore deserving to be explored toward its potential application as a complementary therapeutic approach to the current treatment options for this type of brain tumor.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , MicroRNAs/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Metabolismo Energético , Perfilação da Expressão Gênica , Glioblastoma/metabolismo , Humanos , RNA Mensageiro/genética
4.
Exp Cell Res ; 370(1): 68-77, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29902537

RESUMO

One of the major challenges in Glioblastoma (GBM) therapy relates with the existence of glioma stem-like cells (GSCs), known to be chemo- and radio-resistant. GSCs and non-stem GBM cells have the ability to interchange, emphasizing the importance of identifying common molecular targets among those cell sub-populations. Nucleolin overexpression has been recently associated with breast cancer sub-populations with different stem-like phenotype. The goal of this work was to evaluate the potential of cell surface nucleolin as a target in GBM cells. Different levels of nucleolin expression resulted in a 3.4-fold higher association of liposomes targeting nucleolin (functionalized with the nucleolin-binding F3 peptide) in U87, relative to GBM11 glioblastoma cells. Moreover, nucleolin was suggested as a potential marker in OCT4-, NANOG-positive GSC, and in the corresponding non-stem GBM cells, as well as in SOX2-positive GSC. Doxorubicin delivered by liposomes targeting nucleolin enabled a level of cytotoxicity that was 2.5- or 4.6-fold higher compared to the non-targeted counterparts. Importantly, an overexpression of nucleolin was also observed in cells of patient-derived samples, as compared with normal brain. Overall, these results suggested nucleolin as a therapeutic target in GBM.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Citotoxinas/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Biomarcadores Tumorais/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Lipossomos/farmacologia , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Nucleolina
5.
Eur Spine J ; 27(4): 815-819, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-27817138

RESUMO

PURPOSE: Although gout is a common metabolic disorder, it usually affects distal joints of the appendicular skeleton. Axial spine involvement is rare, with only 131 cases reported in the literature. The authors report a rare case of lumbar spinal gout mimicking a spinal meningioma. METHODS: A 77-year-old man with a history of gout presented with chronic low back pain and progressive paraparesis. Imaging revealed a lumbar spine compressive mass lesion with a dural tail signal. The differential diagnosis was thought to be straightforward favoring a spinal meningioma. Tophaceous gout was never considered. The presence of a dural tail associated with the lesion is an interesting detail of this case, that strongly misguided it and to the best of our knowledge it is the first one reported in the literature. RESULTS: The patient underwent surgery and intra-operative findings were surprisingly different from those expected, revealing a chalky white mass lesion firmly adherent and compressing the dural sac. It was completely excised, leaving the dura intact. Histopathology confirmed the diagnosis of tophaceous gout. The patient was sent to physical therapy and had a complete remission of pain and neurological deficit, regaining his walking capacity. CONCLUSION: Although spinal gout is rare, it should be considered in the differential diagnosis for patients presenting with symptoms of spinal stenosis, a suspicion of neoplastic lesion of the spine, and a previous history of gout. Early diagnosis can ensure proper and timely medical management, perhaps avoiding neurological compromise and the need for surgery.


Assuntos
Gota/diagnóstico , Vértebras Lombares/patologia , Meningioma/diagnóstico , Estenose Espinal/etiologia , Idoso , Diagnóstico Diferencial , Gota/complicações , Gota/cirurgia , Humanos , Dor Lombar/etiologia , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/diagnóstico , Estenose Espinal/cirurgia
6.
Cell Mol Life Sci ; 73(24): 4701-4716, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27376435

RESUMO

Methylphenidate (MPH) is an amphetamine-like stimulant commonly prescribed for attention deficit hyperactivity disorder. Despite its widespread use, the cellular/molecular effects of MPH remain elusive. Here, we report a novel direct role of MPH on the regulation of macromolecular flux through human brain endothelial cells (ECs). MPH significantly increased caveolae-mediated transcytosis of horseradish peroxidase through ECs without affecting paracellular permeability. Using FRET-based live cell imaging, together with pharmacological inhibitors and lentiviral-mediated shRNA knockdown, we demonstrate that MPH promoted ROS generation via activation of Rac1-dependent NADPH oxidase (NOX) and c-Src activation at the plasma membrane. c-Src in turn was shown to mediate the phosphorylation of caveolin-1 (Cav1) on Tyr14 leading to enhanced caveolae formation and transendothelial transport. Accordingly, the inhibition of Cav1 phosphorylation by overexpression of a phosphodefective Cav1Y14F mutant or knocking down Cav1 expression abrogated MPH-induced transcytosis. In addition, both vitamin C and inhibition of NOX blocked MPH-triggered vesicular transport. This study, therefore, identifies Rac1/NOX/c-Src-dependent signaling in MPH-induced increase in transendothelial permeability of brain endothelial cell monolayers via caveolae-mediated transcytosis.


Assuntos
Cavéolas/metabolismo , Caveolina 1/metabolismo , Células Endoteliais/metabolismo , Metilfenidato/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transcitose/efeitos dos fármacos , Proteínas rac1 de Ligação ao GTP/metabolismo , Quinases da Família src/metabolismo , Transporte Biológico/efeitos dos fármacos , Encéfalo/citologia , Proteína Tirosina Quinase CSK , Permeabilidade Capilar/efeitos dos fármacos , Cavéolas/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Modelos Biológicos , NADPH Oxidases/metabolismo , Oxidantes/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Vesículas Transportadoras/efeitos dos fármacos , Vesículas Transportadoras/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
7.
World Neurosurg ; 149: e877-e893, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33516862

RESUMO

BACKGROUND: Meningiomas are the most common primary brain tumors and are generally considered benign. However, a rare subgroup of meningiomas, classified as World Health Organization (WHO) grade III meningiomas, can show extremely aggressive behavior and high rates of recurrence. Despite ongoing research, data on the clinical outcome of this subgroup of meningiomas are still limited. METHODS: Medical records of patients with WHO grade III meningiomas diagnosed between 2000 and 2018 at the Coimbra University Hospital Center were retrospectively reviewed and several variables of interest and their relation to patients' survival were analyzed. RESULTS: Of the 26 patients included in the final analysis, 23 had anaplastic meningiomas, 2 had papillary meningiomas, and 1 had a rhabdoid meningioma. Median overall survival and median progression-free survival were 2.45 and 1.22 years, respectively. Overall survival at 1, 2 and 5 years was 73%, 57%, and 35%, respectively. Adjuvant radiotherapy correlated with improved survival for subtotally resected meningiomas but not for gross totally resected meningiomas. There was a trend toward improved overall survival with gross total resection versus subtotal resection, but this difference failed to reach statistical significance. CONCLUSIONS: This study provides insight into the clinical outcomes of WHO grade III meningiomas and suggests that adjuvant radiotherapy may not be beneficial for patients who underwent gross total resection. This rare subset of meningiomas still portends a devastating prognosis and the impact of extent of resection and adjuvant therapies in these patients needs further clarification.


Assuntos
Neoplasias Encefálicas/cirurgia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Recidiva Local de Neoplasia/cirurgia , Centros Médicos Acadêmicos , Neoplasias Encefálicas/diagnóstico , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Gradação de Tumores/métodos , Recidiva Local de Neoplasia/diagnóstico , Intervalo Livre de Progressão , Radioterapia Adjuvante/métodos , Organização Mundial da Saúde
8.
Rev Esc Enferm USP ; 44(4): 947-55, 2010 Dec.
Artigo em Português | MEDLINE | ID: mdl-21337776

RESUMO

The objective of this study was to validate the reprocessing of angiographic cardiac catheters regarding their characteristics of mechanical functionality and the molecular and micro-structural integrity of the polymeric chain.This is an experimental, applied, comparative and controlled study. A simulation set was built for a left coronary angiography in order to simulate mechanical and biological stress in the catheters. Traction tests were performed for the functionality and the integrity was tested through Infrared Spectrometry and Scanning Electronic Microscopy. The study evidenced a tendency to an increase in rigidity at every increment of the reprocessing number (p < 0.05). The changes in the mechanical properties and molecular structures of the polymers were more evident as of the fifth reprocessing. Micrographies revealed an increase in rugosity as of the forth reprocessing. The results of this study may contribute to the elaboration of reprocessing protocols and a systematic surveillance of the reutilization of single use materials, not only due to their economical relevance, but especially from the ethical, legal, biological, functional and care point of view.


Assuntos
Cateterismo Cardíaco/instrumentação , Angiografia Coronária/instrumentação , Reutilização de Equipamento/normas , Humanos
9.
World Neurosurg ; 140: 325-331, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32461181

RESUMO

BACKGROUND: Solitary spinal amyloidoma (SSA) is a rare and poorly characterized disease. There are few cases described, and the knowledge of this neoplasm is limited. A more accurate description of demographics, clinical findings, and outcomes may be useful for a better understanding of this pathology, as well as therapeutic intervention, adding value to the research of localized amyloidosis. METHODS: A systematic search was carried out from when registries began until February 2020. We also include a case diagnosed and treated in our department. Descriptive statistics were used to evaluate data, demographics, clinical findings, diagnostic modalities, therapeutics, and finally neurologic outcomes. The Kaplan-Meier method was used to assess overall survival and progression-free survival. RESULTS: The final cohort comprises 35 patients. The mean age at diagnosis was 61.97 years, and 68.60% of the patients were male. SSA developed more frequently in the thoracic spine (48.60%), followed by the cervical spine (17.10%). Intradural lesions were rare, and the average neoplastic score for spinal instability was 9.5 points. The most common symptoms were impaired motor function (74.29%) and axial back pain (65.70%). After surgery, neurologic recovery was reported in 82.90% of cases. Mean progression-free survival and mean overall survival were 47.26 and 156.66 months. CONCLUSIONS: SSA is a rare subgroup of localized amyloidosis, usually being diagnosed in male patients between the sixth and eighth decades. The gold standard treatment seems to be surgical resection. SSA patients have excellent long-term survival and a low rate of local recurrence.


Assuntos
Amiloidose/cirurgia , Coluna Vertebral/cirurgia , Amiloidose/patologia , Feminino , Humanos , Masculino , Doenças da Coluna Vertebral/patologia , Doenças da Coluna Vertebral/cirurgia , Coluna Vertebral/patologia , Resultado do Tratamento
10.
Ground Water ; 58(6): 987-992, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32112404

RESUMO

A new version of the computer program FLASH (Flow-Log Analysis of Single Holes) is presented for the analysis of borehole vertical flow logs to estimate fracture (or layer) transmissivities and far-field hydraulic heads. The program is written in R, an open-source environment. All previous features have been retained and new features incorporated including more rigorous parameter estimation, uncertainty analysis, and improved data import. The program has a dynamic user interface compatible with most operating systems.


Assuntos
Água Subterrânea , Movimentos da Água , Modelos Teóricos , Software
11.
Eur Neuropsychopharmacol ; 29(2): 195-210, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30554860

RESUMO

Methylphenidate (MPH) is the classic treatment for attention deficit hyperactivity disorder (ADHD) among children and adults. Despite its beneficial effects, non-medical use of MPH is nowadays a problem with high impact on society. Thus, our goal was to uncover the neurovascular and cognitive effects of MPH chronic use during a critical period of development in control conditions. For that, male Wistar Kyoto rats were treated with MPH (1.5 or 5 mg/kg/day at weekdays, per os) from P28 to P55. We concluded that the higher dose of MPH caused hippocampal blood-brain barrier (BBB) hyperpermeability by vesicular transport (transcytosis) concomitantly with the presence of peripheral immune cells in the brain parenchyma. These observations were confirmed by in vitro studies, in which the knockdown of caveolin-1 in human brain endothelial cells prevented the increased permeability and leukocytes transmigration triggered by MPH (100 µM, 24 h). Furthermore, MPH led to astrocytic atrophy and to a decrease in the levels of several synaptic proteins and impairment of AKT/CREB signaling, together with working memory deficit assessed in the Y-maze test. On the contrary, we verified that the lower dose of MPH (1.5 mg/kg/day) increased astrocytic processes and upregulated several neuronal proteins as well as signaling pathways involved in synaptic plasticity culminating in working memory improvement. In conclusion, the present study reveals that a lower dose of MPH in normal rats improves memory performance being associated with the modulation of astrocytic morphology and synaptic machinery. However, a higher dose of MPH leads to BBB dysfunction and memory impairment.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Metilfenidato/farmacologia , Transcitose/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Antioxidantes/metabolismo , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Hipocampo/anatomia & histologia , Hipocampo/ultraestrutura , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/efeitos dos fármacos , Neuroglia/ultraestrutura , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transcitose/fisiologia , Regulação para Cima/efeitos dos fármacos
12.
Oncotarget ; 9(46): 28083-28102, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29963263

RESUMO

Several classification systems have been proposed to address genomic heterogeneity of glioblastoma multiforme, but they either showed limited prognostic value and/or are difficult to implement in routine diagnostics. Here we propose a prognostic stratification model for these primary tumors based on tumor gene amplification profiles, that might be easily implemented in routine diagnostics, and potentially improve the patients management. Gene amplification profiles were prospectively evaluated in 80 primary glioblastoma multiforme tumors using single-nucleotide polymorphism arrays and the results obtained validated in publicly available data from 267/347 cases. Gene amplification was detected in 45% of patients, and chromosome 7p11.2 including the EGFR gene, was the most frequently amplified chromosomal region - either alone (18%) or in combination with amplification of DNA sequences in other chromosomal regions (10% of cases). Other frequently amplified DNA sequences included regions in chromosomes 12q(10%), 4q12(7%) and 1q32.1(4%). Based on their gene amplification profiles, glioblastomas were subdivided into: i) tumors with no gene amplification (55%); ii) tumors with chromosome 7p/EGFR gene amplification (with or without amplification of other chromosomal regions) (38%); and iii) glioblastoma multiforme with a single (11%) or multiple (6%) amplified DNA sequences in chromosomal regions other than chromosome 7p. From the prognostic point of view, these amplification profiles showed a significant impact on overall survival of glioblastoma multiforme patients (p>0.001). Based on these gene amplification profiles, a risk-stratification scoring system was built for prognostic stratification of glioblastoma which might be easily implemented in routine diagnostics, and potentially contribute to improved patient management.

13.
Cienc. act. fís. (Talca, En línea) ; 23(especial): 1-10, jun. 2022. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-1404096

RESUMO

RESUMEN Este estudio tuvo como objetivo describir la agregación de comportamientos del estilo de vida en adolescentes brasileños e identificar la asociación de estas agregaciones con el exceso de peso. Se ha utilizado información sobre el consumo alimentario, tiempo frente a la televisión y práctica de actividad física de una muestra compuesta por 14141 adolescentes, de ambos sexos, con edades entre 11 y 17 años, procedente de la Encuesta Nacional de Salud del Escolar (2015), que fueron divididos en tres clases: físicamente activos (FA), comportamiento de riesgo (CR) e inactivos físicamente con alimentación saludable (IA). Los resultados mostraron que las niñas y adolescentes mayores tienen menos probabilidades de desarrollar exceso de peso en comparación con los niños y adolescentes más jóvenes, así como los sujetos pertenecientes a la clase CR, que tienen menos probabilidades de presentar exceso de peso, mientras que los adolescentes de clase IA tienen más probabilidades en comparación con la FA. Se puede concluir que la adopción de hábitos saludables parece ejercer una influencia importante en cuanto al resultado de sobrepeso, ya que, no obstante, la adopción de alimentación "no saludable" es prevalente en la clase CR, los niveles de actividad física se asemejan a la clase FA, que puede mitigar los efectos de los comportamientos negativos relacionados con la alimentación.


ABSTRACT This study aimed to describe the cluster of lifestyle behaviors among Brazilian adolescents and to identify the association of these clusters with overweight. Information related to food consumption, TV time and physical activity were used, from a sample of 14141 adolescents of both sexes, aged between 11 and 17 years, from the National School Health Survey (2015), who were split into three classes: physically active (FA), risky behavior (CR), and physically inactive with healthy eating (AI). Results showed that girls and older adolescents have less chances to be overweight when compared to boys and younger adolescents, respectively. Moreover, subjects classified as CR have less chances of being overweight, whereas those classified as AI are more prone to be overweight compared to those belonging to FA class. We conclude that the adoption of healthy habits seems to be of relevance in the expression of overweight, because although the high prevalence of "unhealthy" diet among subjects from the CR class, their physical activity levels are similar to their peers from the FA class, which may mitigate the impacts unhealthy behaviors associated with food consumption.


RESUMO Este estudo teve como objetivo descrever a agregação de comportamentos de estilo de vida em adolescentes brasileiros e identificar a associação dessas agregações com o excesso de peso. Informações sobre consumo alimentar, tempo em frente à televisão e prática de atividade física de uma amostra composta por 14141 adolescentes, de ambos os sexos, com idade entre 11 e 17 anos, da Pesquisa Nacional de Saúde do Escolar (2015), que foram divididos em três classes: fisicamente ativo (AF), comportamento de risco (CR) e fisicamente inativo com alimentação saudável (IA). Os resultados mostraram que meninas e adolescentes mais velhos são menos propensos a desenvolver excesso de peso em comparação com crianças e adolescentes mais novos, assim como os sujeitos pertencentes à classe CR, que são menos propensos ao excesso de peso, enquanto os adolescentes da classe IA são mais propensos em relação aos AF. Pode-se concluir que a adoção de hábitos saudáveis parece ter influência importante no resultado do excesso de peso, pois, no entanto, a adoção de dietas "não saudáveis" é prevalente na classe CR, os níveis de atividade física são semelhantes aos da classe AF, o que pode atenuar os efeitos de comportamentos negativos relacionados à alimentação.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adolescente , Sobrepeso/diagnóstico , Comportamentos de Risco à Saúde , Exercício Físico , Inquéritos e Questionários , Comportamento Alimentar
14.
Transl Oncol ; 10(4): 555-569, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28654819

RESUMO

Glioblastoma (GBM) is the most malignant primary brain tumor, with an average survival rate of 15 months. GBM is highly refractory to therapy, and such unresponsiveness is due, primarily, but not exclusively, to the glioma stem-like cells (GSCs). This subpopulation express stem-like cell markers and is responsible for the heterogeneity of GBM, generating multiple differentiated cell phenotypes. However, how GBMs maintain the balance between stem and non-stem populations is still poorly understood. We investigated the GBM ability to interconvert between stem and non-stem states through the evaluation of the expression of specific stem cell markers as well as cell communication proteins. We evaluated the molecular and phenotypic characteristics of GSCs derived from differentiated GBM cell lines by comparing their stem-like cell properties and expression of connexins. We showed that non-GSCs as well as GSCs can undergo successive cycles of gain and loss of stem properties, demonstrating a bidirectional cellular plasticity model that is accompanied by changes on connexins expression. Our findings indicate that the interconversion between non-GSCs and GSCs can be modulated by extracellular factors culminating on differential expression of stem-like cell markers and cell-cell communication proteins. Ultimately, we observed that stem markers are mostly expressed on GBMs rather than on low-grade astrocytomas, suggesting that the presence of GSCs is a feature of high-grade gliomas. Together, our data demonstrate the utmost importance of the understanding of stem cell plasticity properties in a way to a step closer to new strategic approaches to potentially eliminate GSCs and, hopefully, prevent tumor recurrence.

15.
Methods Mol Med ; 129: 115-26, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17085808

RESUMO

Hypertension is an important disease with polygenic inheritance. In order to identify the genes involved in blood pressure regulation, hypertensive rat and mouse models have been developed either by selective breeding or by transgenic technology. The most essential technological prerequisite in these studies is a reliable assessment of the blood pressure in rodents. Three methods are used most frequently for this purpose: tail cuff plethysmography, intra-arterial catheters, and radiotelemetry. Plethysmography is noninvasive, relatively simple, and suitable for a large number of animals, but also imprecise. Intra-arterial catheters are more precise, but require surgery. And both methods restrain and thereby stress the animals, which leads to alterations in blood pressure. Therefore, the telemetric blood pressure measurement, which allows the study of conscious, freely moving animals, has become the gold standard for measuring blood pressure in rodents. However, this method is extremely expensive. Thus, for each experiment the costs have to be put in relation to the quality of data required. This chapter will describe blood pressure measurement methods in technical detail.


Assuntos
Determinação da Pressão Arterial/métodos , Modelos Animais de Doenças , Animais , Pressão Sanguínea/fisiologia , Cateterismo Cardíaco/métodos , Hipertensão/fisiopatologia , Camundongos , Pletismografia/métodos , Ratos , Telemetria/métodos
16.
Methods Mol Med ; 112: 339-52, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16010028

RESUMO

Myocardial hypertrophy is an adaptational process of the heart to increased workload caused by mechanical stress, growth factors, cytokines, catecholamines, or primary genetic abnormalities. Chronic induction of hypertrophy leads to the gradual deterioration of ventricular function and is an independent risk factor for cardiac-related morbidity and mortality in patients with hypertension and ventricular arrythmias. Transgenic animals are very useful models to study the factors involved in the pathogenesis of cardiac hypertrophy. To achieve this goal, rodents lacking or overexpressing a specific gene are subjected to banding of the abdominal aorta, an experimental model of cardiac hypertrophy that leads to pressure overload on the heart. After periods between 3 and 21 d, parameters such as cardiac hemodynamics, morphologic alterations, and expression of marker genes (e.g., the gene for atrial natriuretic peptide) are analyzed in genetically modified animals and compared with controls elucidating a possible implication of the modified gene in the pathogenic process leading to myocardial hypertrophy. This article summarizes the techniques necessary to induce left ventricular hypertrophy by aortic banding and to analyze the effects of this experimental model on hemodynamics, cardiac morphology, and gene expression of transgenic and control animals.


Assuntos
Cardiomegalia/etiologia , Cardiomegalia/genética , Modelos Animais de Doenças , Animais , Animais Geneticamente Modificados , Cardiomegalia/patologia , Expressão Gênica , Marcadores Genéticos , Hemodinâmica , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/patologia , Camundongos , Camundongos Transgênicos , Biologia Molecular/métodos , Ratos
17.
Braz J Cardiovasc Surg ; 30(5): 579-85, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26735606

RESUMO

OBJECTIVE: In 1996, the Brazilian cardiovascular surgeon, Dr. Randas Batista, introduced a surgical technique called partial left ventriculectomy, where he admitted the possibility of reducing the diameter of the left ventricle through the sectioning of one section of its wall. After the publication of this study, thousands of case reports and procedure analysis have been published, and due to several disappointing results, many doctors and institutions failed to execute it. As the main objective of this study, stands out the search for success cases of ventriculectomy in the last 12 years and if during this period it was achieved some significant development in this procedure that allows obtaining lower mortality rate postoperatively. METHODS: Systematic review of indexed scientific literature over the past 12 years and the term "Partial Left Ventriculectomy". RESULTS: There has been a considerable number of reported successful cases and highly significant findings in regard to determining the most suitable region for the section, proper selection of the patients indicated to the procedure, including the influence of the coronary artery anatomy in the nomination procedure and the need for preservation of ventricular geometry to ensure better quality of ventricular contractions after the sectioning. CONCLUSION: This surgical procedure has been successfully performed, mainly in Japan, improvements in its efficiency were found and the need for a mathematical modeling of the slice to be severed is a prominent factor in many studies.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Cardiomiopatia Dilatada/cirurgia , Difusão de Inovações , Ventrículos do Coração/cirurgia , Cardiomiopatia Dilatada/mortalidade , Humanos , Japão , Modelos Teóricos , Período Pós-Operatório
18.
JBRA Assist Reprod ; 19(1): 24-8, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27205863

RESUMO

Since the beginning of in vitro fertilization (IVF) 36 years ago, scientists have studied and critically analyzed the techniques in order to find ways to improve outcomes. However, success rates vary significantly among clinics due to poor reproducibility and inconsistency across operators. Much research has been conducted on the chemical environment, or culture medium, surrounding the oocyte/ embryo, but little attention has been given to the actual equipment and physical culture environment, which has changed very little over the years. The aim of this paper was to evaluate how the physical factors are important regulators of oocyte and embryo function and to improve understanding of the physical forces involved in the processes in human reproduction. A review the available literature was conducted using PubMed from 1966 through July 2014 in an attempt to help integrate mechanics into our understanding of the molecular basis of IVF. Keywords included in vitro fertilization, biomechanics, bioengineering, oocyte and embryo. The mechanical characterization of oocytes and embryos represents an opportunity to detect cellular defects, assess quality and bio-viability of processes such as cryopreservation as well as select the best embryo for transfer. Defining the mechanical forces at play during embryo transfer is also an important step towards improving results in in vitro fertilization. The further analysis of these phenomena needs a detailed monitoring of the mechanical conditions and more extensive studies of events on the cellular and molecular levels.

19.
Arq. bras. neurocir ; 39(2): 95-100, 15/06/2020.
Artigo em Inglês | LILACS | ID: biblio-1362537

RESUMO

Object The timing of definitive management of ruptured intracranial aneurysms has been the subject of considerable debate, although the benefits of early surgery (until 72 hours postictus) are widely accepted. The aim of the present study is to evaluate the potential benefit of ultra-early surgery (until 24 hours) when compared with early surgery, in those patients who were treated by surgical clipping at the Neurosurgery Department of the Coimbra Hospital and University Centre. Methods A 17-year database of consecutive ruptured and surgically treated intracranial aneurysms was analyzed. Outcome was measured by the Glasgow Outcome Scale (GOS). Baseline characteristics were analyzed by the Fisher exact test, the chi-squared and Mann-Whitney tests. Logistic regression was used to assess the impact of good grade according to the World Federation of Neurological Surgeons (WFNS) scale and ultra-early surgery in a good GOS outcome. Results 343 patients who were submitted to surgical clipping in the first 72 hours postictus were included, 165 of whom have undergone ultra-early surgery. Demographics and preoperative characteristics of ultra-early and early surgery patients were similar. Goodgrade patients according to the WFNS scale submitted to ultra-early surgery demonstrated an improvedGOS at discharge and at 6months. Poor-grade patients according to theWFNS scale submitted to ultra-early surgery demonstrated an improved GOS at discharge. Conclusions Ultra-early surgery for aneurysmal subarachnoid hemorrhage patients improves outcome mainly on good-grade patients. Efforts should be made on the logistics of emergency departments to consider achieving treatment on this timeframe as a standard of care.


Assuntos
Hemorragia Subaracnóidea/terapia , Aneurisma Intracraniano/terapia , Intervenção Médica Precoce/métodos , Tempo para o Tratamento , Hemorragia Subaracnóidea/complicações , Distribuição de Qui-Quadrado , Modelos Logísticos , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Estatísticas não Paramétricas
20.
J Cereb Blood Flow Metab ; 35(8): 1260-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25899299

RESUMO

Methamphetamine (METH) is a psychostimulant that causes neurologic and psychiatric abnormalities. Recent studies have suggested that its neurotoxicity may also result from its ability to compromise the blood-brain barrier (BBB). Herein, we show that METH rapidly increased the vesicular transport across endothelial cells (ECs), followed by an increase of paracellular transport. Moreover, METH triggered the release of tumor necrosis factor-alpha (TNF-α), and the blockade of this cytokine or the inhibition of nuclear factor-kappa B (NF-κB) pathway prevented endothelial dysfunction. Since astrocytes have a crucial role in modulating BBB function, we further showed that conditioned medium obtained from astrocytes previously exposed to METH had a negative impact on barrier properties also via TNF-α/NF-κB pathway. Animal studies corroborated the in vitro results. Overall, we show that METH directly interferes with EC properties or indirectly via astrocytes through the release of TNF-α and subsequent activation of NF-κB pathway culminating in barrier dysfunction.


Assuntos
Barreira Hematoencefálica/metabolismo , Estimulantes do Sistema Nervoso Central/efeitos adversos , Células Endoteliais/metabolismo , Metanfetamina/efeitos adversos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Estimulantes do Sistema Nervoso Central/farmacologia , Células Endoteliais/patologia , Metanfetamina/farmacologia , Ratos , Ratos Wistar
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