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1.
Adv Exp Med Biol ; 1131: 27-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646506

RESUMO

Ca2+, Na+ and K+- permeable ion channels as well as GPCRs linked to Ca2+ release are important drug targets. Accordingly, high-throughput fluorescence plate reader assays have contributed substantially to drug discovery efforts and pharmacological characterization of these receptors and ion channels. This chapter describes some of the basic properties of the fluorescent dyes facilitating these assay approaches as well as general methods for establishment and optimisation of fluorescence assays for ion channels and Gq-coupled GPCRs.


Assuntos
Bioensaio , Canais Iônicos , Receptores Acoplados a Proteínas-G , Animais , Bioensaio/tendências , Descoberta de Drogas , Corantes Fluorescentes/metabolismo , Humanos , Canais Iônicos/análise , Receptores Acoplados a Proteínas-G/análise
2.
Biosens Bioelectron ; 124-125: 150-160, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30368106

RESUMO

Cell-based assays including both cell identification assays and cell functional assays are broadly used in life science research and for medical applications. Traditionally, cell-based assays are performed in professional laboratories. Although such an approach is reliable, it significantly limits the accessibility of cell-based assays by many researchers without specialized cell imaging facilities and does not permit on-site use at most clinics. Over recent years, growing efforts have been made to overcome this limitation by developing various portable cell imaging platforms. Herein, we provide a timely review on the recent development of portable imaging systems and their biomedical applications. We describe the respective applications of three main classes of portable imaging technologies including miniaturized microscope, lens-free imaging device and smartphone-based microscope for cell-based assays. We conclude by discussing our views on the opportunities, problems and future directions of this emerging field.


Assuntos
Técnicas Biossensoriais , Microscopia/tendências , Imagem Molecular/tendências , Smartphone , Bioensaio/tendências , Humanos , Sistemas Automatizados de Assistência Junto ao Leito
3.
Clin Pharmacol Ther ; 102(5): 777-785, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28160285

RESUMO

Planning and transfer of a new technology platform developed in an academic setting to a start-up company for medical diagnostic product development may appear daunting and costly in terms of complexity, time, and resources. In this review we outline the key steps taken and lessons learned when a technology platform developed in an academic setting was transferred to a start-up company for medical diagnostic product development in the interest of elucidating development toolkits for academic groups and small start-up companies starting on the path to commercialization and regulatory approval.


Assuntos
Bioensaio/métodos , Células Neoplásicas Circulantes/metabolismo , Transferência de Tecnologia , Pesquisa Médica Translacional/métodos , Bioensaio/tendências , Humanos , Células Neoplásicas Circulantes/química , Pesquisa Médica Translacional/tendências
5.
Adv Biochem Eng Biotechnol ; 157: 159-186, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27864593

RESUMO

This chapter reviews the current knowledge and recent progress in the field of environmental, aquatic ecotoxicogenomics with a focus on transcriptomic methods. In ecotoxicogenomics the omics technologies are applied for the detection and assessment of adverse effects in the environment, and thus are to be distinguished from omics used in human toxicology [Snape et al., Aquat Toxicol 67:143-154, 2004]. Transcriptomic methods in ecotoxicology are applied to gain a mechanistic understanding of toxic effects on organisms or populations, and thus aim to bridge the gap between cause and effect. A worthwhile effect-based interpretation of stressor induced changes on the transcriptome is based on the principle of phenotypic-anchoring [Paules, Environ Health Perspect 111:A338-A339, 2003]. Thereby, changes on the transcriptomic level can only be identified as effects if they are clearly linked to a specific stressor-induced effect on the macroscopic level. By integrating those macroscopic and transcriptomic effects, conclusions on the effect-inducing type of the stressor can be drawn. Stressor-specific effects on the transcriptomic level can be identified as stressor-specific induced pathways, transcriptomic patterns, or stressors-specific genetic biomarkers. In this chapter, examples of the combined application of macroscopic and transcriptional effects for the identification of environmental stressors, such as aquatic pollutants, are given and discussed. By means of these examples, challenges on the way to a standardized application of transcriptomics in ecotoxicology are discussed. This is also done against the background of the application of transcriptomic methods in environmental regulation such as the EU regulation Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Testes de Mutagenicidade/métodos , Toxicogenética/métodos , Animais , Bioensaio/métodos , Bioensaio/tendências , Ecologia/métodos , Ecologia/tendências , Ecotoxicologia/métodos , Ecotoxicologia/tendências , Perfilação da Expressão Gênica/tendências , Sequenciamento de Nucleotídeos em Larga Escala/tendências , Humanos , Testes de Mutagenicidade/tendências , Mutagênicos/toxicidade , Medição de Risco/métodos , Medição de Risco/tendências , Toxicogenética/tendências , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
6.
AAPS J ; 18(6): 1366-1372, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27514862

RESUMO

With the growing focus on translational research and the use of biomarkers to drive drug development and approvals, biomarkers have become a significant area of research within the pharmaceutical industry. However, until the US Food and Drug Administration's (FDA) 2013 draft guidance on bioanalytical method validation included consideration of biomarker assays using LC-MS and LBA, those assays were created, validated, and used without standards of performance. This lack of expectations resulted in the FDA receiving data from assays of varying quality in support of efficacy and safety claims. The AAPS Crystal City VI (CC VI) Workshop in 2015 was held as the first forum for industry-FDA discussion around the general issues of biomarker measurements (e.g., endogenous levels) and specific technology strengths and weaknesses. The 2-day workshop served to develop a common understanding among the industrial scientific community of the issues around biomarkers, informed the FDA of the current state of the science, and will serve as a basis for further dialogue as experience with biomarkers expands with both groups.


Assuntos
Bioensaio/normas , Indústria Farmacêutica/normas , Educação/normas , Controle de Qualidade , Relatório de Pesquisa/normas , United States Food and Drug Administration/normas , Bioensaio/tendências , Biomarcadores , Indústria Farmacêutica/tendências , Educação/tendências , Humanos , Reprodutibilidade dos Testes , Relatório de Pesquisa/tendências , Estados Unidos , United States Food and Drug Administration/tendências , Virginia
7.
AAPS J ; 18(5): 1056-66, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27350147

RESUMO

The availability of reliable assays for measuring 4ß-hydroxycholesterol (4ß-HC), a CYP3A metabolite of cholesterol, is an important step in qualifying this endogenous moiety as a biomarker of CYP3A activity. Liquid and gas chromatographic methods with mass spectrometric detection have been developed with varying sensitivities, with or without derivatization. Care must be taken to chromatographically resolve 4ß-HC from the multiple isobaric cholesterol oxidation products present in plasma, including 4α-hydroxycholesterol (4α-HC). Plasma concentrations of 4ß-HC are low in humans (10-60 ng/ml), lower than many other cholesterol metabolites and far less than cholesterol itself. Stability of 4ß-HC has been established for at least 12 months at -20°C in plasma samples obtained with a typical clinical workflow. Oxidation of plasma cholesterol during storage produces both 4ß-HC and 4α-HC, and 4α-HC may be used as assessment of sample quality. As 4ß-HC concentrations over time in untreated individuals have low intra-individual variability, assay precision and reproducibility are the key assay attributes in assessing CYP3A4 induction, and potentially inhibition. Assessment of CYP3A4/5 activity with 4ß-HC relies on the differences between pre- and post-dose concentrations, in which each subject acts as their own control. To reduce analytical variability, samples from a single subject should be analyzed together to facilitate interpretation of study results. As an endogenous biomarker, 4ß-HC offers the opportunity for less invasive assessment of CYP3A induction potential of new drugs during clinical development.


Assuntos
Bioensaio/tendências , Citocromo P-450 CYP3A/metabolismo , Hidroxicolesteróis/metabolismo , Preparações Farmacêuticas/metabolismo , Animais , Bioensaio/métodos , Biomarcadores/metabolismo , Citocromo P-450 CYP3A/química , Humanos , Hidroxicolesteróis/química , Preparações Farmacêuticas/química , Espectrometria de Massas em Tandem/métodos
8.
Integr Biol (Camb) ; 8(5): 585-8, 2016 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-27146265

RESUMO

Synthetic biology follows the traditional engineering paradigm of designing, building, testing and learning to create new biological systems. While such approaches have enormous potential, major challenges still exist in this field including increasing the speed at which this workflow can be performed. Here, we present recently developed microfluidic tools that can be used to automate the synthetic biology workflow with the goal of advancing the likelihood of producing desired functionalities. With the potential for programmability, automation, and robustness, the integration of microfluidics and synthetic biology has the potential to accelerate advances in areas such as bioenergy, health, and biomaterials.


Assuntos
Técnicas de Cultura Celular por Lotes/tendências , Bioensaio/tendências , Engenharia Genética/tendências , Ensaios de Triagem em Larga Escala/tendências , Dispositivos Lab-On-A-Chip/tendências , Biologia Sintética/tendências
10.
J Lab Autom ; 21(5): 615-24, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26721822

RESUMO

High-quality preclinical bioassay models are essential for drug research and development. We reviewed the emerging body-on-a-chip technology, which serves as a promising model to overcome the limitations of traditional bioassay models, and introduced existing models of body-on-a-chip, their constitutional details, application for drug testing, and individual features of these models. We put special emphasis on the latest trend in this field of incorporating barrier tissue into body-on-a-chip and discussed several remaining challenges of current body-on-a-chip.


Assuntos
Bioensaio/instrumentação , Bioensaio/métodos , Descoberta de Drogas/instrumentação , Descoberta de Drogas/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Bioensaio/tendências , Descoberta de Drogas/tendências , Humanos , Dispositivos Lab-On-A-Chip/tendências , Técnicas Analíticas Microfluídicas/tendências
11.
Naunyn Schmiedebergs Arch Pharmacol ; 389(2): 201-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26612506

RESUMO

Having observed a large variation in the number and type of original preclinical publications for newly registered drugs, we have explored whether longitudinal trends and/or factors specific for certain drugs or their manufacturers may explain such variation. Our analysis is based on 1954 articles related to 170 newly approved drugs. The number of preclinical publications per compound declined from a median of 10.5 in 1991 to 3 in 2011. A similar trend was observed for the number of in vivo studies in general, but not in the subset of in vivo studies in animal models of disease. The percentage of compounds with studies using isolated human cells or cell lines almost doubled over time from 37 to 72%. Number of publications did not exhibit major differences between compounds intended for human versus veterinary use, therapeutic areas, small molecules versus biologicals, or innovator versus follow-up compounds; however, some companies may publish fewer studies per compound than others. However, there were qualitative differences in the types of models being used depending on the therapeutic area; specifically, compounds for use in oncology very often used isolated cells and cell lines, often from human origin. We conclude that the large variation in number and type of reported preclinical data is not easily explained. We propose that pharmaceutical companies should consistently provide a comprehensive documentation of the preclinical data they generate as part of their development programs in the public domain to enable a better understanding of the drugs they intend to market.


Assuntos
Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos/tendências , Publicações Periódicas como Assunto/tendências , Projetos de Pesquisa/tendências , United States Food and Drug Administration , Alternativas aos Testes com Animais/tendências , Animais , Bibliometria , Bioensaio/tendências , Humanos , Estudos Longitudinais , Farmacocinética , Fatores de Tempo , Testes de Toxicidade/tendências , Estados Unidos
12.
Ann Biol Clin (Paris) ; 74(1): 21-7, 2016 Jan-Feb.
Artigo em Francês | MEDLINE | ID: mdl-26711165

RESUMO

Thyroglobulin (Tg) is a high molecular weight glycoprotein located mainly in thyroid follicles, where thyroid hormones are synthesized and stored. In patients with differentiated thyroid cancer of follicular origin, serum Tg levels become undetectable following total thyroidectomy and iodine-131 remnant ablation. It is a key biomarker to follow-up patients with differentiated thyroid cancer, in combination with neck ultrasound monitoring. The measurement of Tg in the wash-out of the needle used for fine needle aspiration biopsy is a valuable aid to the diagnosis of lymph node metastasis. The presence of anti-thyroglobulin antibodies affects reliability of Tg results measured in serum or plasma. Systematic investigation of such antibodies is required to validate any Tg assay. Elevated or rising levels of anti-thyroglobulin antibodies can in turn be used as a surrogate tumor marker of thyroid cancer. The development of second-generation Tg assay (automated, highly sensitive) has enabled significant advances in the management of differentiated thyroid cancer: early detection of persistent or recurrent disease and follow-up care simplified in low-risk patients. Testing of serum Tg can also be useful in evaluating other clinical situations such as congenital hypothyroidism, endemic goiter and thyrotoxicosis factitia.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Tireoglobulina/análise , Tireoglobulina/sangue , Testes de Função Tireóidea/tendências , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Autoanticorpos/análise , Autoanticorpos/sangue , Bioensaio/métodos , Bioensaio/normas , Bioensaio/tendências , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Humanos , Monitorização Fisiológica/métodos , Prognóstico , Reprodutibilidade dos Testes , Testes de Função Tireóidea/métodos , Testes de Função Tireóidea/normas , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/patologia
14.
Comb Chem High Throughput Screen ; 18(10): 952-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26377542

RESUMO

This review describes the principle and applications of bioluminescent enzymatic toxicity bioassays. This type of assays uses bacterial coupled enzyme systems: NADH:FMN-oxidoreductase and luciferase to replace living organisms in developing cost-competitive biosensors for environmental, medical and industrial applications. These biosensors instantly signal chemical and biological hazards and allow for detecting a great amount of toxic compounds with advantages associated with fast results, high sensitivity, simplicity, low cost and safety of the procedure.


Assuntos
Bactérias/enzimologia , Medições Luminescentes , Toxicologia/métodos , Toxicologia/tendências , Bioensaio/tendências , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo
16.
Toxicol Pathol ; 43(8): 1064-73, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26296629

RESUMO

Throughout the last 50 years, the paradigm for carcinogenicity assessment has depended on lifetime bioassays in rodents. Since 1997, the International Conference on Harmonisation (ICH) S1B has permitted the use of a 2-year rodent bioassay (usually in the rat) and an alternative, genetically modified mouse model to support cancer risk assessment of pharmaceuticals. Since its introduction, it has become apparent that many of the stated advantages of the 6-month Tg mouse bioassay have, in actual fact, not been realized, and the concern exists that an albeit imperfect, 2-year mouse bioassay has been replaced by a similarly imperfect 6-month equivalent. This essay argues strongly that model systems, using cancer as the end point, should be discontinued, and that the recent initiatives, from the Organization for Economic Cooperation and Development and Institute of Peace and Conflict Studies, on "mode of action," "adverse outcome pathways," and "human relevance framework" should be embraced as being risk assessments based upon the available science. The recent suggested revisions to the ICH S1 guidelines, utilizing carcinogenicity assessment documents, go some way to developing a science-based risk assessment that does not depend almost entirely on a single, imperfect, cancer-based end point in nonrelevant animal species.


Assuntos
Bioensaio , Testes de Carcinogenicidade , Animais , Animais Geneticamente Modificados , Bioensaio/história , Bioensaio/métodos , Bioensaio/tendências , Testes de Carcinogenicidade/história , Testes de Carcinogenicidade/métodos , Testes de Carcinogenicidade/tendências , História do Século XX , História do Século XXI , Camundongos , Neoplasias Experimentais , Ratos , Medição de Risco
19.
J Pharmacol Toxicol Methods ; 76: 27-37, 2015 Nov-Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26159293

RESUMO

INTRODUCTION: The comprehensive in vitro proarrhythmia assay (CiPA) is a nonclinical, mechanism-based paradigm for assessing drug proarrhythmic liability. TOPICS COVERED: The first CiPA assay determines effects on cloned human cardiac ion channels. The second investigates whether the latter study-generated metrics engender proarrhythmic markers on a computationally reconstructed human ventricular action potential. The third evaluates conclusions from, and searches possibly missed effects by in silico analysis, in human stem cell-derived cardiomyocytes (hSC-CMs). CiPA ad hoc Expert-Working Groups have proposed patch clamp protocols for seven cardiac ion channels, a modified O'Hara-Rudy model for in silico analysis, detailed procedures for field (MEA) and action potential (VSD) measurements in hSC-CMs, and 29 reference drugs for CiPA assay testing and validation. DISCUSSION: CiPA adoption as drug development tool for identifying electrophysiological mechanisms conferring proarrhythmic liability to candidate drugs is a complex, multi-functional task requiring significant time, reflection, and efforts to be fully achieved.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Bioensaio/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Drogas em Investigação/efeitos adversos , Guias como Assunto , Potenciais de Ação/efeitos dos fármacos , Bioensaio/normas , Bioensaio/tendências , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/normas , Avaliação Pré-Clínica de Medicamentos/tendências , Guias como Assunto/normas , Humanos , Canais Iônicos/metabolismo , Japão , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Reprodutibilidade dos Testes , Células-Tronco/efeitos dos fármacos , Estados Unidos , United States Food and Drug Administration
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