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2.
Dose Response ; 17(1): 1559325818825172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30728758

RESUMO

Very little is known about the effects of whole body vibration on the supraspinal central nervous system. Though much clinical outcome data and mechanistic data about peripheral neural and musculoskeletal mechanisms have been explored, the lack of central understanding is a barrier to evidence-based, best practice guidelines in the use of vibrational therapy. Disparate methods of administration render study to study comparisons difficult. To address this lack of uniformity, we present the use of targeted subcutaneous vibration combined with simultaneous in vivo electrophysiological recordings as a method of exploring the central effects of peripheral vibration therapy. We used implanted motors driven by both Grass stimulators and programmed microcontrollers to vary frequency and location of stimulation in an anesthetized in vivo rat model while simultaneously recording firing rate from gamma-aminobutyric acid (GABA) neurons in the ventral tegmental area. We show that peripheral vibration can alter GABA neuron firing rate in a location- and frequency-dependent manner. We include detailed schematics and code to aid others in the replication of this technique. This method allows for control of previous weaknesses in the literature including variability in body position, vibrational intensity, node and anti-node interactions with areas of differing mechanoreceptor densities, and prefrontal cortex influence.

3.
In. Pinto, Ibraim Masciarelli Francisco; Smanio, Paola Emanuela P; Mathias Junior, Wilson. Fascículo o coração do atleta. São Paulo, Grupo Fleury, 2016. p.96-101.
Monografia em Português | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1084275
5.
Nat Med ; 19(6): 664, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23744139

RESUMO

Almost 50 years ago, the World Medical Association adopted the Declaration of Helsinki as an ethical guide for research involving human subjects. There are now proposed revisions under consideration that will provide additional protection for study participants as well as increased clarity regarding the responsibilities of those conducting the research. Making these changes is important in a complex environment where what is ethical is not always self-evident.


Assuntos
Ensaios Clínicos como Assunto , Declaração de Helsinki , Humanos
8.
Aliment Pharmacol Ther ; 32(4): 535-42, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20500732

RESUMO

BACKGROUND: Poor adherence to Hepatitis C virus (HCV) treatment is an important cause of treatment failure. Traditional ribavirin 200 mg (RBV) treatment is associated with a significant daily pill burden. RibaPak (RBP), available as 400 mg and 600 mg ribavirin tablets, offers simplified dosing at two pills daily. AIM: To examine whether improved adherence was associated with RBP vs. RBV. METHODS: Accurate Dosing in Hepatitis C: Examining the RibaPak Experience (ADHERE) was a U.S., multi-centre, prospective registry capturing data on adherence with RBP vs. RBV in adults with HCV. Adherence was measured by the proportion of subjects remaining on treatment at weeks 4, 12 and 24; by pill counts; and by the proportion of subjects who took > or = 80% of their prescribed dose. RESULTS: A total of 503 patients (RBP = 346, RBV = 157) from 33 sites were included. A greater proportion of RBV vs. RBP subjects prematurely discontinued treatment. At 12 and 24 weeks, a greater proportion of RBP vs. RBV subjects took > or = 80% of their prescribed doses (P < 0.05). For patients who remained on treatment, the mean milligrams missed per day was significantly greater for RBV vs. RBP at 24 weeks. CONCLUSIONS: First line treatment with RBP may offer the best prospect for less discontinuation and improved treatment adherence.


Assuntos
Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Adesão à Medicação , Ribavirina/administração & dosagem , Administração Oral , Adulto , Antivirais/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Ribavirina/uso terapêutico
9.
J Biol Chem ; 284(20): 13291-5, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19182219

RESUMO

A major mechanism in the cellular defense against oxidative or electrophilic stress is activation of the Nrf2-antioxidant response element signaling pathway, which controls the expression of genes whose protein products are involved in the detoxication and elimination of reactive oxidants and electrophilic agents through conjugative reactions and by enhancing cellular antioxidant capacity. At the molecular level, however, the regulatory mechanisms involved in mediating Nrf2 activation are not fully understood. It is well established that Nrf2 activity is controlled, in part, by the cytosolic protein Keap1, but the nature of this pathway and the mechanisms by which Keap1 acts to repress Nrf2 activity remain to be fully characterized and are the topics of discussion in this minireview. In addition, a possible role of the Nrf2-antioxidant response element transcriptional pathway in neuroprotection will also be discussed.


Assuntos
Antioxidantes , Fator 2 Relacionado a NF-E2/biossíntese , Estresse Oxidativo/fisiologia , Elementos de Resposta/fisiologia , Transdução de Sinais/fisiologia , Transcrição Gênica/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/metabolismo
10.
Gerontol Geriatr Educ ; 29(3): 257-69, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19042505

RESUMO

This article describes recent trends that have led to an emphasis on a learner-centered approach to gerontology and geriatrics education especially in distance-based education. A learner-centered approach to education has combined with technological advances to stimulate distance-enhanced education for students in geriatric and gerontology programs. The technological advances, especially the Internet, that have enhanced the capacity of educational programs to involve students in the learning process even though separated from the instructor by time and distance, are discussed. In response to the needs of health care professionals who were seeking to enhance their skills in research, education, and leadership in their respective professions, including gerontology, the learner-centered Doctoral Program in Health-Related Sciences (DPHRS) was established in the School of Allied Health Professions of Virginia Commonwealth University. The specifics of this distance-enhanced, learner-centered program are described. The article ends with strategies for encouraging a learner-centered experience with special focus on distance-based education.


Assuntos
Educação a Distância/métodos , Geriatria/educação , Pessoal de Saúde/educação , Internet , Aprendizagem , Envelhecimento , Comunicação , Avaliação Educacional , Humanos
11.
Mol Cell Biol ; 25(24): 10895-906, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16314513

RESUMO

Nrf2 is a transcription factor critical for the maintenance of cellular redox homeostasis. We have previously found that Nrf2 is a labile protein, and its activation in cells under stress involves mechanisms leading to its stabilization. As a modular protein, Nrf2 possesses distinct transactivation and DNA binding domains essential for its transcriptional activity. In this study, we found that the C-terminal "Neh3" domain of Nrf2 is also important for its activity. Deletion of the last 16 amino acids of the protein completely abolishes its ability to activate both reporter and endogenous gene expression. Using site-directed mutagenesis, we have identified a stretch of amino acids within this region that are essential for its activity and that are found to be conserved across species and among other members of the CNC-bZIP family. Importantly, deletion of the final 16 amino acids of Nrf2 does not influence its dimerizing capability, DNA binding activity, or subcellular localization, although it does increase the half-life of the protein. In addition, this region was found to be important for interaction with CHD6 (a chromo-ATPase/helicase DNA binding protein) in a yeast two-hybrid screen. RNA interference-mediated knockdown of CHD6 reduced both the basal and tert-butylhydroquinone-inducible expression of NQO1, a prototypical Nrf2 target gene. These data suggest that the Neh3 domain may act as a transactivation domain and that it is possibly involved in interaction with components of the transcriptional apparatus to affect its transcriptional activity.


Assuntos
Fator 2 Relacionado a NF-E2/química , Fator 2 Relacionado a NF-E2/metabolismo , Ativação Transcricional , Sequência de Aminoácidos , Animais , Núcleo Celular/química , Núcleo Celular/metabolismo , Células Cultivadas , Sequência Conservada , Dimerização , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fator 2 Relacionado a NF-E2/genética , Estrutura Terciária de Proteína , Proteínas/metabolismo , Interferência de RNA , Ratos , Elementos de Resposta , Deleção de Sequência , Técnicas do Sistema de Duplo-Híbrido
12.
Emerg Infect Dis ; 11(8): 1294-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16102323

RESUMO

We report West Nile virus (WNV) RNA in urine collected from a patient with encephalitis 8 days after symptom onset. Viral RNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Sequence and phylogenetic analysis confirmed the PCR product to have > or = 99% similarity to the WNV strain NY 2000-crow3356.


Assuntos
Febre do Nilo Ocidental/urina , Vírus do Nilo Ocidental/isolamento & purificação , Idoso , Anticorpos Antivirais/sangue , Análise por Conglomerados , Humanos , Masculino , Filogenia , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Febre do Nilo Ocidental/tratamento farmacológico , Vírus do Nilo Ocidental/genética
13.
J Biol Chem ; 280(37): 32485-92, 2005 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-16000310

RESUMO

Nrf2 regulates the expression of genes encoding antioxidant proteins involved in cellular redox homeostasis. Previous studies have suggested that activation of Nrf2 is mediated by mechanisms promoting its dissociation from Keap1, a cytosolic repressor that acts to sequester the transcription factor in the cytoplasm. As a short-lived protein, Nrf2 is also activated by mechanisms leading to its stabilization in cells under stress, and recent evidence indicates that Keap1 has an active role in the control of its stability. In this report, using immunocytochemistry, cell fractionation, and chromatin immunoprecipitation analyses, we found that Nrf2 is primarily a nuclear protein and that it is expressed and recruited to the chromatin constitutively to drive basal gene expression. Furthermore, we found evidence indicating that Keap1 may repress Nrf2 activity by transiently shuttling into the nucleus to promote its ubiquitylation. The data suggested that the steady-state level of Nrf2 is maintained by a dynamic pathway that balances its constitutive expression with a Keap1-regulated degradation process downstream of its role as a transcriptional activator. We suggest that the stabilization of Nrf2 in cells under stress represents the central regulatory response mediated by mechanisms that interfere with its interaction with Keap1, leading to the induction of antioxidant enzymes important to maintain cellular redox homeostasis.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Proteínas/fisiologia , Transativadores/fisiologia , Transporte Ativo do Núcleo Celular , Animais , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Citosol/metabolismo , Proteínas de Ligação a DNA/química , Glutationa Transferase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular , Proteína 1 Associada a ECH Semelhante a Kelch , Microscopia Confocal , Modelos Biológicos , Fator 2 Relacionado a NF-E2 , Oxirredução , Ligação Proteica , Transporte Proteico , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Frações Subcelulares/metabolismo , Fatores de Tempo , Transativadores/química , Ubiquitina/química , Ubiquitina/metabolismo
14.
Free Radic Biol Med ; 37(4): 433-41, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15256215

RESUMO

The induction of many antioxidant and phase II drug-metabolizing enzymes by phenolic antioxidants and electrophilic compounds is regulated at the transcriptional level. The response to these compounds is mediated by the cis-acting antioxidant response element (ARE) found in the promoter of the encoding genes. The transcription factor NF-E2-related factor 2, or Nrf2, has emerged as the central protein that binds to the ARE to activate gene transcription. Data from many studies indicate that Nrf2 is constitutively and ubiquitously expressed in a number of tissues and cell lines and is thus responsible for the low-level expression of its target genes observed under physiological conditions. However, in cells exposed to oxidative stress, Nrf2 activity is increased, further driving the transcriptional activation of genes whose expression is essential to control cellular redox homeostasis. Recent studies suggest that the activation of Nrf2 involves a coordinated process and is regulated at multiple levels. Nrf2 activity is believed to be repressed through the binding of the cytoskeleton-associated protein Keap1, and its activation involves mechanisms that interfere with this interaction. Activation of Nrf2 has also been demonstrated to be dependent on mechanisms that mediate its stabilization. In this review, the mechanisms controlling this activation process as reported in recent studies will be examined and discussed, with particular emphasis on those affecting Nrf2 stability at the molecular level.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Transdução de Sinais , Transativadores/fisiologia , Animais , Antioxidantes/metabolismo , Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteína 1 Associada a ECH Semelhante a Kelch , Reagentes de Laboratório , Modelos Biológicos , Fator 2 Relacionado a NF-E2 , Oxirredução , Estresse Oxidativo , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas/fisiologia , Elementos de Resposta , Transativadores/metabolismo , Transcrição Gênica
16.
Am J Public Health ; 93(11): 1922-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14600067

RESUMO

OBJECTIVES: We describe the tobacco industry's effort in Massachusetts to block the adoption of local regulations designed to reduce youth access to tobacco products. We also explain how state-funded tobacco control advocates overcame industry opposition. METHODS: We examined internal tobacco industry documents and records of local boards of health and conducted interviews with participants in local regulatory debates. RESULTS: The industry fought proposed regulations by working through a trade group, the New England Convenience Store Association. With industry direction and financing, the association's members argued against proposed regulations in local public hearings. However, these efforts failed because community-based advocates worked assiduously to cultivate support for the regulations among board of health members and local community organizations. CONCLUSIONS: Passage of youth access regulations by local boards of health in Massachusetts is attributed to ongoing state funding for local tobacco control initiatives, agreement on common policy goals among tobacco control advocates, and a strategy of persuading boards of health to adopt and enforce their own local regulations.


Assuntos
Proteção da Criança/legislação & jurisprudência , Comércio/legislação & jurisprudência , Regulamentação Governamental , Política , Administração em Saúde Pública , Indústria do Tabaco/legislação & jurisprudência , Adolescente , Criança , Defesa do Consumidor/legislação & jurisprudência , Humanos , Aplicação da Lei , Massachusetts , Comunicação Persuasiva
17.
Genome ; 46(3): 343-52, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12834049

RESUMO

Here we bring together our published and unpublished work with recent published findings of other laboratories to provide a revised map of the centromeric heterochromatin of chromosome 2 and descriptions of the 21 genetic elements therein. These elements consist of 16 vital loci, one male and one female sterile loci, one Minute locus, and two components of the Segregation Distorter system. Based on our latest analysis of the lethal mutant phenotypes of the vital genes, we have provided names for several genes that were previously known by their lethal number assignments.


Assuntos
Centrômero/genética , Mapeamento Cromossômico , Drosophila melanogaster/genética , Heterocromatina/genética , Animais , Proteínas de Drosophila/genética , Proteínas Ativadoras de GTPase/genética
18.
J Biol Chem ; 278(7): 4536-41, 2003 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-12446695

RESUMO

Nrf2 (NF-E2-related factor 2) is a central transcription factor involved in the transcriptional activation of many genes encoding phase II drug-metabolizing enzymes via the antioxidant response element. Nrf2 has previously been found to undergo nuclear translocation by a phosphorylation-dependent mechanism mediated by protein kinase C in HepG2 cells treated with tert-butylhydroquinone, beta-naphthoflavone, or 12-O-tetradecanoylphorbol-13-acetate. In the present report, we have found that the levels of Nrf2 were increased in cells treated with tert-butylhydroquinone or beta-naphthoflavone by a post-transcriptional mechanism. Treatment of HepG2 cells with cycloheximide resulted in the loss of Nrf2 within 30 min. By contrast, treatment with the proteasome inhibitors (lactacystin or MG-132) caused an accumulation of Nrf2 as well as an induction of reporter gene activity in cells transfected with the GSTA2 antioxidant response element-chloramphenicol acetyl transferase construct. Similarly, the protein phosphatase inhibitor okadaic acid also caused an accumulation of Nrf2, whereas the reverse effects were observed with PD 98059 and U 0126, two compounds that block the activation of the MAPK/ERK signaling cascade. These data suggest that Nrf2 is degraded by the ubiquitin-dependent pathway and that phosphorylation of Nrf2 leads to an increase in its stability and subsequent transactivation activity.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Peptídeo Hidrolases/metabolismo , Complexo de Endopeptidases do Proteassoma , Transativadores/genética , Transativadores/metabolismo , Antioxidantes/farmacologia , Butadienos/farmacologia , Linhagem Celular , Proteínas de Ligação a DNA/química , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Humanos , Hidroquinonas/farmacologia , Zíper de Leucina , Fator 2 Relacionado a NF-E2 , Nitrilas/farmacologia , Estresse Oxidativo/genética , Fosforilação , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , Transativadores/química , Ativação Transcricional/efeitos dos fármacos , beta-Naftoflavona/farmacologia
19.
Annu Rev Pharmacol Toxicol ; 43: 233-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12359864

RESUMO

The expression of genes encoding antioxidative and Phase II detoxification enzymes is induced in cells exposed to electrophilic compounds and phenolic antioxidants. Induction of these enzymes is regulated at the transcriptional level and is mediated by a specific enhancer, the antioxidant response element or ARE, found in the promoter of the enzyme's gene. The transcription factor Nrf2 has been implicated as the central protein that interacts with the ARE to activate gene transcription constitutively or in response to an oxidative stress signal. This review focuses on the molecular mechanisms whereby the transcriptional activation mediated by the interaction between the ARE and NF-E2-related factor 2 (Nrf2) is regulated. Recent studies suggest that the sequence context of the ARE, the nature of the chemical inducers, and the cell type are important for determining the activity of the enhancer in a particular gene.


Assuntos
Antioxidantes/metabolismo , Elementos de Resposta/genética , Transdução de Sinais/genética , Ativação Transcricional , Animais , Proteínas de Ligação a DNA/genética , Humanos , Fator 2 Relacionado a NF-E2 , Ratos , Transativadores/genética
20.
J Biol Chem ; 277(45): 42769-74, 2002 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-12198130

RESUMO

Nrf2, a basic leucine zipper transcription factor, is an essential activator of the coordinated transcription of genes encoding antioxidant enzymes and phase II detoxifying enzymes through the regulatory sequence termed antioxidant response element (ARE). Recently we reported evidence for the involvement of protein kinase C (PKC) in phosphorylating Nrf2 and triggering its nuclear translocation in response to oxidative stress. We show here that phosphorylation of purified rat Nrf2 by the catalytic subunit of PKC was blocked by a synthetic peptide mimicking one of the potential PKC sites. Accordingly, Nrf2 bearing a Ser to Ala mutation at amino acid 40 (S40A) could not be phosphorylated by PKC. The S40A mutation did not affect in vitro binding of Nrf2/MafK to the ARE. However, it partially impaired Nrf2 activation of ARE-driven transcription in a reporter gene assay when Keap1 was overexpressed. In vitro transcribed/translated Keap1 could be coimmunoprecipitated with Nrf2. Phosphorylation of wild-type Nrf2 by PKC promoted its dissociation from Keap1, whereas the Nrf2-S40A mutant remained associated. These findings together with our prior studies suggest that the PKC-catalyzed phosphorylation of Nrf2 at Ser-40 is a critical signaling event leading to ARE-mediated cellular antioxidant response.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Fosfosserina/metabolismo , Transativadores/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Sondas de DNA , DNA Complementar , Proteínas de Ligação a DNA/genética , Cinética , Zíper de Leucina , Dados de Sequência Molecular , Fator 2 Relacionado a NF-E2 , Fragmentos de Peptídeos/farmacologia , Ratos , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Transativadores/genética
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