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1.
Artigo em Inglês | MEDLINE | ID: mdl-33138270

RESUMO

The Coronavirus Disease 2019 (COVID-19) outbreak has created an unprecedented impact on global health and further aggravated the physical inactivity pandemic. For this reason, the understanding of sociodemographic variables in the context of physical activity levels are important for the field of public health in order to assist in relevant public health decisions. Our main aim was to characterize sociodemographic variables and physical activity levels and their association with COVID-19 aspects. We applied an online Google survey with closed questions in Brazilian people of different age and regions, both sexes and physical activity levels (n = 1.726). Our main results were that participants who had symptoms of COVID-19 had the highest percentage of level 1 of physical activity (the lowest level according to the classification used) and those who showed no symptoms had the highest percentage of levels 2 and 3 of physical activity; that is, close to the light/moderate levels of physical activity. This cross-sectional study in the Brazilian population provided important sociodemographic data and COVID-19 aspects regarding the level of physical activity. It is possible to assume that the regular practice of physical activity could positively impact health status and quality of life and be a tool in the field of public health to cope (from a physical and mental point of view) with disease scenarios that require quarantine.


Assuntos
Infecções por Coronavirus/epidemiologia , Coronavirus , Exercício Físico , Pneumonia Viral/epidemiologia , Qualidade de Vida/psicologia , Adolescente , Adulto , Idoso , Betacoronavirus , Brasil/epidemiologia , COVID-19 , Estudos Transversais , Surtos de Doenças , Feminino , Humanos , Internet , Masculino , Saúde Mental , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
2.
Cancers (Basel) ; 12(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847043

RESUMO

Claspin is a multifunctional protein that participates in physiological processes essential for cell homeostasis that are often defective in cancer, namely due to genetic changes. It is conceivable that Claspin gene (CLSPN) alterations may contribute to cancer development. Therefore, CLSPN germline alterations were characterized in sporadic and familial breast cancer and glioma samples, as well as in six cancer cell lines. Their association to cancer susceptibility and functional impact were investigated. Eight variants were identified (c.-68C>T, c.17G>A, c.1574A>G, c.2230T>C, c.2028+16G>A, c.3595-3597del, and c.3839C>T). CLSPN c.1574A>G (p.Asn525Ser) was significantly associated with breast cancer and was shown to cause partial exon skipping and decreased Claspin expression and Chk1 activation in a minigene splicing assay and in signalling experiments, respectively. CLSPN c.2028+16G>A was significantly associated with familial breast cancer and glioma, whereas c.2230T>C (p.Ser744Pro), was exclusively detected in breast cancer and glioma patients, but not in healthy controls. The remaining variants lacked a significant association with cancer. Nevertheless, the c.-68C>T promoter variant increased transcriptional activity in a luciferase assay. In conclusion, some of the CLSPN variants identified in the present study appear to modulate Claspin's function by altering CLSPN transcription and RNA processing, as well as Chk1 activation.

3.
J Nat Prod ; 79(5): 1423-8, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27135143

RESUMO

Luteolin is a dietary flavonoid with medicinal properties including antioxidant, antimicrobial, anticancer, antiallergic, and anti-inflammatory. However, the effect of luteolin on liver X receptors (LXRs), oxysterol sensors that regulate cholesterol homeostasis, lipogenesis, and inflammation, has yet to be studied. To unveil the potential of luteolin as an LXRα/ß modulator, we investigated by real-time RT-PCR the expression of LXR-target genes, namely, sterol regulatory element binding protein 1c (SREBP-1c) in hepatocytes and ATP-binding cassette transporter (ABC)A1 in macrophages. The lipid content of hepatocytes was evaluated by Oil Red staining. The results demonstrated, for the first time, that luteolin abrogated the LXRα/ß agonist-induced LXRα/ß transcriptional activity and, consequently, inhibited SREBP-1c expression, lipid accumulation, and ABCA1 expression. Therefore, luteolin could abrogate hypertriglyceridemia associated with LXR activation, thus presenting putative therapeutic effects in diseases associated with deregulated lipid metabolism, such as hepatic steatosis, cardiovascular diseases, and diabetes.


Assuntos
Flavonas/farmacologia , Receptores X do Fígado/antagonistas & inibidores , Luteolina/farmacologia , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos , Fígado/efeitos dos fármacos , Luteolina/química , Estrutura Molecular , Reação em Cadeia da Polimerase , Proteína de Ligação a Elemento Regulador de Esterol 1/efeitos dos fármacos
4.
Pharmacol Res ; 95-96: 2-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25749008

RESUMO

Glioblastoma is characterized by constitutive apoptosis resistance and survival signaling expression, but paradoxically is a necrosis-prone neoplasm. Incubation of human U118 glioblastoma cells with the antitumor alkylphospholipid analog edelfosine induced a potent necrotic cell death, whereas apoptosis was scarce. Preincubation of U118 cells with the selective MEK1/2 inhibitor U0126, which inhibits MEK1/2-mediated activation of ERK1/2, led to a switch from necrosis to caspase-dependent apoptosis following edelfosine treatment. Combined treatment of U0126 and edelfosine totally inhibited ERK1/2 phosphorylation, and led to RIPK1 and RelA/NF-κB degradation, together with a strong activation of caspase-3 and -8. This apoptotic response was accompanied by the activation of the intrinsic apoptotic pathway with mitochondrial transmembrane potential loss, Bcl-xL degradation and caspase-9 activation. Inhibition of ERK phosphorylation also led to a dramatic increase in edelfosine-induced apoptosis when the alkylphospholipid analog was used at a low micromolar range, suggesting that ERK phosphorylation acts as a potent regulator of apoptotic cell death in edelfosine-treated U118 cells. These data show that inhibition of MEK1/2-ERK1/2 signaling pathway highly potentiates edelfosine-induced apoptosis in glioblastoma U118 cells and switches the type of edelfosine-induced cell death from necrosis to apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Éteres Fosfolipídicos/farmacologia , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/enzimologia , Butadienos/farmacologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Glioblastoma/tratamento farmacológico , Glioblastoma/enzimologia , Humanos , Microscopia de Fluorescência , Necrose , Nitrilas/farmacologia , Fosforilação , Proteína Serina-Treonina Quinases de Interação com Receptores/biossíntese
5.
J Nat Prod ; 77(2): 264-9, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24455984

RESUMO

Previous studies have suggested that α-pinene, a common volatile plant metabolite, may have anti-inflammatory effects in human chondrocytes, thus exhibiting potential antiosteoarthritic activity. The objective of this study was to further characterize the potential antiosteoarthritic activity of selected pinene derivatives by evaluating their ability to modulate inflammation and extracellular matrix remodeling in human chondrocytes and to correlate the biological and chemical properties by determining whether the effects are isomer- and/or enantiomer-selective. To further elucidate chemicopharmacological interactions, the activities of other naturally occurring monoterpenes with the pinane nucleus were also investigated. At noncytotoxic concentrations, (+)-α-pinene (1) elicited the most potent inhibition of the IL-1ß-induced inflammatory and catabolic pathways, namely, NF-κB and JNK activation and the expression of the inflammatory (iNOS) and catabolic (MMP-1 and -13) genes. (-)-α-Pinene (2) was less active than the (+)-enantiomer (1), and ß-pinene (3) was inactive. E-Pinane (4) and oxygenated pinane-derived compounds, pinocarveol (5), myrtenal (6), (E)-myrtanol (7), myrtenol (8), and (Z)-verbenol (9), were less effective or even completely inactive and more cytotoxic than the pinenes tested (1-3). The data obtained show isomer- and enantiomer-selective anti-inflammatory and anticatabolic effects of α-pinene in human chondrocytes, (+)-α-pinene (1) being the most promising for further studies to determine its potential value as an antiosteoarthritic drug.


Assuntos
Anti-Inflamatórios/farmacologia , Condrócitos/efeitos dos fármacos , Monoterpenos/farmacologia , Osteoartrite/tratamento farmacológico , Anti-Inflamatórios/química , Monoterpenos Bicíclicos , Humanos , Interleucina-1beta/metabolismo , MAP Quinase Quinase 4/efeitos dos fármacos , Estrutura Molecular , Monoterpenos/química , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Estereoisomerismo , Terpenos/farmacologia
6.
Phys Med Biol ; 58(9): 2939-53, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23574810

RESUMO

Generally, the inverse planning of radiation therapy consists mainly of the fluence optimization. The beam angle optimization (BAO) in intensity-modulated radiation therapy (IMRT) consists of selecting appropriate radiation incidence directions and may influence the quality of the IMRT plans, both to enhance better organ sparing and to improve tumor coverage. However, in clinical practice, most of the time, beam directions continue to be manually selected by the treatment planner without objective and rigorous criteria. The goal of this paper is to introduce a novel approach that uses beam's-eye-view dose ray tracing metrics within a pattern search method framework in the optimization of the highly non-convex BAO problem. Pattern search methods are derivative-free optimization methods that require a few function evaluations to progress and converge and have the ability to better avoid local entrapment. The pattern search method framework is composed of a search step and a poll step at each iteration. The poll step performs a local search in a mesh neighborhood and ensures the convergence to a local minimizer or stationary point. The search step provides the flexibility for a global search since it allows searches away from the neighborhood of the current iterate. Beam's-eye-view dose metrics assign a score to each radiation beam direction and can be used within the pattern search framework furnishing a priori knowledge of the problem so that directions with larger dosimetric scores are tested first. A set of clinical cases of head-and-neck tumors treated at the Portuguese Institute of Oncology of Coimbra is used to discuss the potential of this approach in the optimization of the BAO problem.


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos
7.
Am J Pathol ; 181(5): 1749-61, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22982440

RESUMO

Meningiomas are primary tumors of the central nervous system composed of both neoplastic and other infiltrating cells. We determined the cellular composition of 51 meningioma samples by multiparameter flow cytometric (MFC) immunophenotyping and investigated the potential relationship between mRNA and protein expression levels of neoplastic cells. For immunophenotypic, morphologic, and cytogenetic characterization of individual cell populations, a large panel of markers was used together with phagocytic/endocytic functional assays and MFC sorting. Overall, our results revealed coexistence of CD45(-) neoplastic cells and CD45(+) immune infiltrating cells in all meningiomas. Infiltrating cells included tissue macrophages, with an HLA-DR(+)CD14(+)CD45(+)CD68(+)CD16(-/+)CD33(-/+) phenotype and high phagocytic/endocytic activity, and a small proportion of cytotoxic lymphocytes (mostly T CD8(+) and natural killer cells). Tumor cells expressed multiple cell adhesion proteins, tetraspanins, HLA-I/HLA-DR molecules, complement regulatory proteins, cell surface ectoenzymes, and growth factor receptors. Noteworthy, the relationship between mRNA and protein levels was variable, depending on the proteins evaluated and the level of infiltration by immune cells. In summary, our results indicate that MFC immunophenotyping provides a reliable tool for the characterization of the patterns of protein expression of different cell populations coexisting in meningioma samples, with a more accurate measure of gene expression profiles of tumor cells at the functional/protein level than conventional mRNA microarray, independently of the degree of infiltration of the tumor by immune cells.


Assuntos
Imunofenotipagem , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Neoplasias Meníngeas/imunologia , Neoplasias Meníngeas/patologia , Meningioma/imunologia , Meningioma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Compartimento Celular , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Neoplasias Meníngeas/genética , Meningioma/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fagocitose , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
J Cell Biochem ; 112(10): 2813-24, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21608018

RESUMO

Cartilage matrix homeostasis involves a dynamic balance between numerous signals that modulate chondrocyte functions. This study aimed at elucidating the role of the extracellular glucose concentration in modulating anabolic and catabolic gene expression in normal and osteoarthritic (OA) human chondrocytes and its ability to modify the gene expression responses induced by pro-anabolic stimuli, namely Transforming Growth Factor-ß (TGF). For this, we analyzed by real time RT-PCR the expression of articular cartilage matrix-specific and non-specific genes, namely collagen types II and I, respectively. The expression of the matrix metalloproteinases (MMPs)-1 and -13, which plays a major role in cartilage degradation in arthritic conditions, and of their tissue inhibitors (TIMP) was also measured. The results showed that exposure to high glucose (30 mM) increased the mRNA levels of both MMPs in OA chondrocytes, whereas in normal ones only MMP-1 increased. Collagen II mRNA was similarly increased in normal and OA chondrocytes, but the increase lasted longer in the later. Exposure to high glucose for 24 h prevented TGF-induced downregulation of MMP-13 gene expression in normal and OA chondrocytes, while the inhibitory effect of TGF on MMP-1 expression was only partially reduced. Other responses were not significantly modified. In conclusion, exposure of human chondrocytes to high glucose, as occurs in vivo in diabetes mellitus patients and in vitro for the production of engineered cartilage, favors the chondrocyte catabolic program. This may promote articular cartilage degradation, facilitating OA development and/or progression, as well as compromise the quality and consequent in vivo efficacy of tissue engineered cartilage.


Assuntos
Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Glucose/farmacologia , Osteoartrite/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite/genética , Fator de Crescimento Transformador beta/farmacologia
10.
Cancer Biol Ther ; 9(1): 56-65, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19923906

RESUMO

Glioblastoma (GBM) is the most aggressive and malignant brain tumor. Recent studies indicated that glioma samples are characterized by increased expression of CXCR4, the CXCL12/SDF-1 chemokine receptor. To better understand the role of CXCR4 in GBM biology we performed an integrated study where we simultaneously evaluate the contribution of the CXCR4/CXCL12 signaling pathway to the proliferation, survival and motility of a human GBM cell line. Our results indicated that CXCR4/CXCL12 axis induced an increase in cell proliferation and in cell motility. The blockage of CXCR4 induced a significant increase of apoptosis. Together, our results indicated that CXCR4/CXCL12 signalling pathway may contribute to GBM development and emphasize the therapeutic potential of this pathway in patients with GBM.


Assuntos
Neoplasias Encefálicas/genética , Proliferação de Células , Quimiocina CXCL12/metabolismo , Glioma/genética , Receptores CXCR4/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Quimiocina CXCL12/genética , Quimiotaxia , Glioblastoma/patologia , Humanos , Receptores CXCR4/genética
11.
Rev Iberoam Micol ; 23(3): 192-3, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17196029

RESUMO

A rust fungus identified as Gymnosporangium cornutum was found on Sorbus aucuparia in Serra da Estrela (Manteigas), and the disease was severe at that location. Despite the abundance and worldwide occurrence of the genus Gymnosporangium, studies in Portugal are still limited.


Assuntos
Basidiomycota/isolamento & purificação , Doenças das Plantas/microbiologia , Sorbus/microbiologia , Basidiomycota/classificação , Basidiomycota/fisiologia , Basidiomycota/ultraestrutura , Portugal
12.
Rev. bras. odontol ; 54(3): 167-70, maio-jun. 1997. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-197415

RESUMO

Foi realizado um estudo para verificar a açäo da luz laser sobre a superfície da dentina e no canal radicular de dentes incisivos e caninos humanos extraídos por indicaçäo clínica. Os dentes foram seccionados longitudinalmente no sentido vestibulo lingual e irradiados com luz laser CO² e Nd:YAG e examinados com auxílio de um microscópio eletrônico de varredura. Os resultados revelaram que a irradiaçäo de luz laser na superfície da dentina provocou uma fusäo e recristalizaçäo da dentina. A comparaçäo de amostras tratadas com luz laser mostrou que a de CO² provocou a formaçäo de uma área vitrificada e áreas irregulares contendo crateras e fendas. Os casos irradiados com laser Nd:YAG revelaram uma superfície contendo uma fusäo de dentina e recristalizaçäo formando áreas verificadas circulares. Notou-se a presença de pequenos forames sobre a superfície vitrificada de dentina fundida


Assuntos
Humanos , Masculino , Feminino , Cavidade Pulpar/efeitos da radiação , Dente Canino , Dentina/efeitos da radiação , Incisivo , Lasers/uso terapêutico , Microscopia Eletrônica de Varredura
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