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1.
Pharmacol Res Perspect ; 10(5): e00995, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36065843

RESUMO

Aldosterone exerts some of its effects not by binding to mineralocorticoid receptors, but rather by acting via G protein-coupled estrogen receptors (GPER). To determine if aldosterone binds directly to GPER, we studied the ability of aldosterone to compete for the binding of [3 H] 2-methoxyestradiol ([3 H] 2-ME), a high potency GPER-selective agonist. We used GPER gene transfer to engineer Sf9-cultured insect cells to express GPER. We chose insect cells to avoid interactions with any intrinsic mammalian receptors for aldosterone. [3 H] 2-ME binding was saturable and reversible to a high-affinity population of receptors with Kd  = 3.7 nM and Bmax  = 2.2 pmol/mg. Consistent with agonist binding to G Protein-coupled receptors, [3 H] 2-ME high-affinity state binding was reduced in the presence of the hydrolysis-resistant GTP analog, GppNHp. [3 H] 2-ME binding was competed for by the GPER agonist G1, the GPER antagonist G15, estradiol (E2), as well as aldosterone (Aldo). The order of potency for competing for [3 H] 2-ME binding, namely 2ME > Aldo > E2 ≥ G1, paralleled the orders of potency for inhibition of cell proliferation and inhibition of ERK phosphorylation by ligands acting at GPER. These data confirm the ability of aldosterone to interact with the GPER, consistent with the interpretation that aldosterone likely mediates its GPER-dependent effects by direct binding to the GPER. SIGNIFICANCE STATEMENT: Despite the growing evidence for aldosterone's actions via G protein-coupled estrogen receptors (GPER), there remains significant skepticism that aldosterone can directly interact with GPER. The current studies are the first to demonstrate directly that aldosterone indeed is capable of binding to the GPER and thus likely mediates its GPER-dependent effects by direct binding to the receptor.


Assuntos
Aldosterona , Receptores de Estrogênio , Aldosterona/metabolismo , Animais , Estrogênios , Proteínas de Ligação ao GTP/metabolismo , Mamíferos/metabolismo , Mercaptoetanol , Receptores Acoplados a Proteínas G/metabolismo
2.
Mol Pharmacol ; 97(1): 49-60, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882404

RESUMO

The American Society for Pharmacology and Experimental Therapeutics has revised the Instructions to Authors for Drug Metabolism and Disposition, Journal of Pharmacology and Experimental Therapeutics, and Molecular Pharmacology These revisions relate to data analysis (including statistical analysis) and reporting but do not tell investigators how to design and perform their experiments. Their overall focus is on greater granularity in the description of what has been done and found. Key recommendations include the need to differentiate between preplanned, hypothesis-testing, and exploratory experiments or studies; explanations of whether key elements of study design, such as sample size and choice of specific statistical tests, had been specified before any data were obtained or adapted thereafter; and explanations of whether any outliers (data points or entire experiments) were eliminated and when the rules for doing so had been defined. Variability should be described by S.D. or interquartile range, and precision should be described by confidence intervals; S.E. should not be used. P values should be used sparingly; in most cases, reporting differences or ratios (effect sizes) with their confidence intervals will be preferred. Depiction of data in figures should provide as much granularity as possible, e.g., by replacing bar graphs with scatter plots wherever feasible and violin or box-and-whisker plots when not. This editorial explains the revisions and the underlying scientific rationale. We believe that these revised guidelines will lead to a less biased and more transparent reporting of research findings.


Assuntos
Guias como Assunto , Farmacologia/normas , Editoração/normas , Projetos de Pesquisa , Sociedades Científicas/normas , Análise de Dados , Interpretação Estatística de Dados , Avaliação Pré-Clínica de Medicamentos/normas , Humanos , Estados Unidos
3.
Drug Metab Dispos ; 48(1): 64-74, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882568

RESUMO

The American Society for Pharmacology and Experimental Therapeutics has revised the Instructions to Authors for Drug Metabolism and Disposition, Journal of Pharmacology and Experimental Therapeutics, and Molecular Pharmacology These revisions relate to data analysis (including statistical analysis) and reporting but do not tell investigators how to design and perform their experiments. Their overall focus is on greater granularity in the description of what has been done and found. Key recommendations include the need to differentiate between preplanned, hypothesis-testing, and exploratory experiments or studies; explanations of whether key elements of study design, such as sample size and choice of specific statistical tests, had been specified before any data were obtained or adapted thereafter; and explanations of whether any outliers (data points or entire experiments) were eliminated and when the rules for doing so had been defined. Variability should be described by S.D. or interquartile range, and precision should be described by confidence intervals; S.E. should not be used. P values should be used sparingly; in most cases, reporting differences or ratios (effect sizes) with their confidence intervals will be preferred. Depiction of data in figures should provide as much granularity as possible, e.g., by replacing bar graphs with scatter plots wherever feasible and violin or box-and-whisker plots when not. This editorial explains the revisions and the underlying scientific rationale. We believe that these revised guidelines will lead to a less biased and more transparent reporting of research findings.


Assuntos
Interpretação Estatística de Dados , Políticas Editoriais , Guias como Assunto/normas , Projetos de Pesquisa/normas , Análise de Dados , Projetos de Pesquisa/estatística & dados numéricos , Projetos de Pesquisa/tendências
4.
J Pharmacol Exp Ther ; 372(1): 136-147, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31884418

RESUMO

The American Society for Pharmacology and Experimental Therapeutics has revised the Instructions to Authors for Drug Metabolism and Disposition, Journal of Pharmacology and Experimental Therapeutics, and Molecular Pharmacology These revisions relate to data analysis (including statistical analysis) and reporting but do not tell investigators how to design and perform their experiments. Their overall focus is on greater granularity in the description of what has been done and found. Key recommendations include the need to differentiate between preplanned, hypothesis-testing, and exploratory experiments or studies; explanations of whether key elements of study design, such as sample size and choice of specific statistical tests, had been specified before any data were obtained or adapted thereafter; and explanation of whether any outliers (data points or entire experiments) were eliminated and when the rules for doing so had been defined. Variability should be described by S.D. or interquartile range, and precision should be described by confidence intervals; S.E. should not be used. P values should be used sparingly; in most cases, reporting differences or ratios (effect sizes) with their confidence intervals will be preferred. Depiction of data in figures should provide as much granularity as possible, e.g., by replacing bar graphs with scatter plots wherever feasible and violin or box-and-whisker plots when not. This editorial explains the revisions and the underlying scientific rationale. We believe that these revised guidelines will lead to a less biased and more transparent reporting of research findings.


Assuntos
Bioestatística/métodos , Políticas Editoriais , Publicações Periódicas como Assunto/normas , Farmacologia/normas , Guias de Prática Clínica como Assunto , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Revisão da Pesquisa por Pares/normas , Farmacologia/organização & administração , Projetos de Pesquisa/normas , Sociedades Científicas
6.
Pharmacol Res Perspect ; 3(1): e00093, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25692012

RESUMO

Ideally, any experienced investigator with the right tools should be able to reproduce a finding published in a peer-reviewed biomedical science journal. In fact, the reproducibility of a large percentage of published findings has been questioned. Undoubtedly, there are many reasons for this, but one reason may be that investigators fool themselves due to a poor understanding of statistical concepts. In particular, investigators often make these mistakes: (1) P-Hacking. This is when you reanalyze a data set in many different ways, or perhaps reanalyze with additional replicates, until you get the result you want. (2) Overemphasis on P values rather than on the actual size of the observed effect. (3) Overuse of statistical hypothesis testing, and being seduced by the word "significant". (4) Overreliance on standard errors, which are often misunderstood.

8.
J Pharmacol Exp Ther ; 351(1): 200-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25204545

RESUMO

Ideally, any experienced investigator with the right tools should be able to reproduce a finding published in a peer-reviewed biomedical science journal. In fact, however, the reproducibility of a large percentage of published findings has been questioned. Undoubtedly, there are many reasons for this, but one reason may be that investigators fool themselves due to a poor understanding of statistical concepts. In particular, investigators often make these mistakes: 1) P-hacking, which is when you reanalyze a data set in many different ways, or perhaps reanalyze with additional replicates, until you get the result you want; 2) overemphasis on P values rather than on the actual size of the observed effect; 3) overuse of statistical hypothesis testing, and being seduced by the word "significant"; and 4) over-reliance on standard errors, which are often misunderstood.


Assuntos
Bioestatística/métodos , Interpretação Estatística de Dados , Reprodutibilidade dos Testes
9.
Naunyn Schmiedebergs Arch Pharmacol ; 387(11): 1017-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25213136

RESUMO

Ideally, any experienced investigator with the right tools should be able to reproduce a finding published in a peer-reviewed biomedical science journal. In fact, the reproducibility of a large percentage of published findings has been questioned. Undoubtedly, there are many reasons for this, but one reason maybe that investigators fool themselves due to a poor understanding of statistical concepts. In particular, investigators often make these mistakes: 1. P-Hacking. This is when you reanalyze a data set in many different ways, or perhaps reanalyze with additional replicates, until you get the result you want. 2. Overemphasis on P values rather than on the actual size of the observed effect. 3. Overuse of statistical hypothesis testing, and being seduced by the word "significant". 4. Overreliance on standard errors, which are often misunderstood.


Assuntos
Interpretação Estatística de Dados , Publicações Periódicas como Assunto/normas , Humanos , Revisão da Pesquisa por Pares , Publicações Periódicas como Assunto/estatística & dados numéricos , Reprodutibilidade dos Testes
10.
Curr Protoc Neurosci ; Chapter 7: Unit 7.5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20578035

RESUMO

Measuring the rate and extent of radioligand binding provides information on the number of binding sites, and their affinity and accessibility of these binding sites for various drugs. This unit explains how to design and analyze such experiments.


Assuntos
Ensaio Radioligante/métodos , Ligação Competitiva , Fluorescência , Polarização de Fluorescência/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Cinética , Ligantes , Modelos Lineares , Modelos Químicos , Dinâmica não Linear , Ligação Proteica , Compostos Radiofarmacêuticos/química , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Análise de Regressão , Espectrometria de Fluorescência/métodos
11.
BMC Bioinformatics ; 7: 123, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16526949

RESUMO

BACKGROUND: Nonlinear regression, like linear regression, assumes that the scatter of data around the ideal curve follows a Gaussian or normal distribution. This assumption leads to the familiar goal of regression: to minimize the sum of the squares of the vertical or Y-value distances between the points and the curve. Outliers can dominate the sum-of-the-squares calculation, and lead to misleading results. However, we know of no practical method for routinely identifying outliers when fitting curves with nonlinear regression. RESULTS: We describe a new method for identifying outliers when fitting data with nonlinear regression. We first fit the data using a robust form of nonlinear regression, based on the assumption that scatter follows a Lorentzian distribution. We devised a new adaptive method that gradually becomes more robust as the method proceeds. To define outliers, we adapted the false discovery rate approach to handling multiple comparisons. We then remove the outliers, and analyze the data using ordinary least-squares regression. Because the method combines robust regression and outlier removal, we call it the ROUT method. When analyzing simulated data, where all scatter is Gaussian, our method detects (falsely) one or more outlier in only about 1-3% of experiments. When analyzing data contaminated with one or several outliers, the ROUT method performs well at outlier identification, with an average False Discovery Rate less than 1%. CONCLUSION: Our method, which combines a new method of robust nonlinear regression with a new method of outlier identification, identifies outliers from nonlinear curve fits with reasonable power and few false positives.


Assuntos
Interpretação Estatística de Dados , Reações Falso-Positivas , Modelos Biológicos , Modelos Estatísticos , Dinâmica não Linear , Análise de Regressão , Simulação por Computador , Análise Numérica Assistida por Computador
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