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2.
Clin Transl Sci ; 15(6): 1332-1339, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35319833

RESUMO

Technological advancements are dramatically changing the landscape of therapeutic development. The convergence of advances in computing power, analytical methods, artificial intelligence, novel digital health tools, and cloud-based platforms has the potential to power an exponential acceleration of evidence generation. For regulatory agencies responsible for evidence evaluation and oversight of medical products, these advances present both promises and challenges. Ultimately, realizing the translation and impact of these innovations that could potentially enhance therapeutic development and improve the health of individuals and the public will require a nimble and responsive regulatory approach. Supporting an adaptive policy-making infrastructure that is poised to address novel regulatory considerations, creating a workforce to ensure relevant expertise, and fostering more diverse collaborations with a broader group of stakeholders are steps toward the goal of modernizing the regulatory ecosystem. This article outlines approaches that can help provide the flexibility and tools needed to foster innovation, while ensuring the safety and effectiveness of medical products.


Assuntos
Inteligência Artificial , Ecossistema , Humanos , Formulação de Políticas
5.
Clin Trials ; 14(4): 342-348, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28503947

RESUMO

Background/aims Use of data monitoring committees to oversee clinical trials was first proposed nearly 50 years ago. Since then, data monitoring committee use in clinical trials has increased and evolved. Nonetheless, there are no well-defined criteria for determining the need for a data monitoring committee, and considerable variability exists in data monitoring committee composition and conduct. To understand and describe the role and function of data monitoring committees, and establish best practices for data monitoring committee trial oversight, the Clinical Trials Transformation Initiative-a public-private partnership to improve clinical trials-launched a multi-stakeholder project. Methods The data monitoring committee project team included 16 individuals charged with (1) clarifying the purpose of data monitoring committees, (2) identifying best practices for independent data monitoring committee conduct, (3) describing effective communication practices, and (4) developing strategies for training data monitoring committee members. Evidence gathering included a survey, a series of focus group discussions, and a 2-day expert meeting aimed at achieving consensus opinions that form the foundation of our data monitoring committee recommendations. Results We define the role of the data monitoring committee as an advisor to the research sponsor on whether to continue, modify, or terminate a trial based on periodic assessment of trial data. Data monitoring committees should remain independent from the sponsor and be composed of members with no relevant conflicts of interest. Representation on a data monitoring committee generally should include at least one clinician with expertise in the therapeutic area being studied, a biostatistician, and a designated chairperson who has experience with clinical trials and data monitoring. Data monitoring committee meetings are held periodically to evaluate the unmasked data from ongoing trials, but the content and conduct of meetings may vary depending on specific goals or topics for deliberation. To guide data monitoring committee conduct and communication plans, a charter consistent with the protocol's research design and statistical analysis plan should be developed and agreed upon by the sponsor and the data monitoring committee prior to patient enrollment. We recommend concise and flexible charters that explain roles, responsibilities, operational issues, and how data monitoring committee recommendations are generated and communicated. The demand for data monitoring committee members appears to exceed the current pool of qualified individuals. To prepare a new generation of trained data monitoring committee members, we encourage a combination of didactic educational programs, practical experience, and skill development through apprenticeships and mentoring by experienced data monitoring committee members. Conclusion Our recommendations address data monitoring committee use, conduct, communication practices, and member preparation and training. Furthermore recommendations form the foundation for ongoing efforts to improve clinical trial oversight and enhance the safety and integrity of clinical research. These recommendations serve as a call to action for implementation of best practices that benefit study participants, study sponsors, and society.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos/organização & administração , Ensaios Clínicos como Assunto , Interpretação Estatística de Dados , Comitês de Monitoramento de Dados de Ensaios Clínicos/normas , Consenso , Humanos , Comunicação Interdisciplinar , Melhoria de Qualidade , Projetos de Pesquisa
6.
Mol Cancer Ther ; 15(6): 1321-31, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27197303

RESUMO

Dysregulation of autophagy has been implicated in various cardiovascular diseases. Trastuzumab, a humanized monoclonal antibody, binds to HER2 domain IV and is approved for the treatment of HER2-positive breast cancer. Trastuzumab therapy is associated with considerable cardiotoxicity, the mechanism of which remains unclear. HER2 signaling plays a pivotal role in cardiomyocyte development and survival and is essential for the prevention of cardiomyopathy. However, a direct link has not been confirmed between trastuzumab-induced cardiomyopathy and impaired HER2 signaling. Our data reveal a novel mechanism by which trastuzumab dysregulates HER2 signaling and impairs basal autophagic process in human primary cardiomyocytes. Specifically, trastuzumab treatment leads to the phosphorylation of HER1-Y845 and HER2-Y1248 and the activation of Erk. This in turn results in upregulation of mTOR signaling pathway and subsequently inhibition of autophagy in primary cardiomyocytes and C57BL/6 mice. Trastuzumab-induced downregulation of autophagy is further supported by the fact that trastuzumab treatment reduces protein levels of autophagosome-associated signaling molecules such as Atg 5-12, Atg 7, Atg 14, and Beclin 1. We further demonstrated that trastuzumab-mediated inhibition of autophagy resulted in the increased production of reactive oxygen species (ROS) in cardiomyocytes. Pertuzumab, another anti-HER2 therapeutic mAb binding to HER2 domain II, fails to modulate HER2 signaling and is unable to inhibit autophagy and to increase ROS production in cardiomyocytes. This study provides novel mechanistic insights into trastuzumab-induced cardiotoxicity, which may assist in formulating novel approaches for clinical management of trastuzumab-induced cardiomyopathy. Mol Cancer Ther; 15(6); 1321-31. ©2016 AACR.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Receptores ErbB/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Receptor ErbB-2/metabolismo , Trastuzumab/efeitos adversos , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Autofagia/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Trastuzumab/farmacologia
7.
Transl Behav Med ; 3(4): 392-401, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24294327

RESUMO

There has been a recent surge of eHealth programs in cancer and other content areas, but few reviews have focused on the methodologies and designs employed in these studies. We conducted a systematic review of studies on eHealth interventions on cancer prevention and control published between 2001 and 2010 applying the Pragmatic Explanatory Continuum Indicator Summary (PRECIS) criteria and external validity components from the Reach Effectiveness Adoption Implementation Maintenance (RE-AIM) framework. We identified 113 studies that focused on cancer prevention and control of eHealth interventions. Most studies fell midway along the explanatory/pragmatic trial continuum, but few reported on various practical feasibility criteria for translation. Despite vast interest in cancer eHealth and the applied nature of this field, few studies considered key external validity issues. There is a need for use of alternative pragmatic study designs and transparent reporting of external validity components to produce more rapid and generalizable results.

8.
PLoS One ; 8(11): e79543, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24255707

RESUMO

Treatment with trastuzumab, a humanized monoclonal antibody directed against the extracellular domain of Human Epidermal Growth Factor Receptor 2 (HER2), very successfully improves outcomes for women with HER2-positive breast cancer. However, trastuzumab treatment was recently linked to potentially irreversible serious cardiotoxicity, the mechanisms of which are largely elusive. This study reports that trastuzumab significantly alters the expression of myocardial genes essential for DNA repair, cardiac and mitochondrial functions, which is associated with impaired left ventricular performance in mice coupled with significant ultrastructural alterations in cardiomyocytes revealed by electron microscopy. Furthermore, trastuzumab treatment also promotes oxidative stress and apoptosis in myocardium of mice, and elevates serum levels of cardiac troponin-I (cTnI) and cardiac myosin light chain-1 (cMLC1). The elevated serum levels of cMLC1 in mice treated with trastuzumab highlights the potential that cMLC1 could be a useful biomarker for trastuzumab-induced cardiotoxicity.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Coração/efeitos dos fármacos , Coração/fisiologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/ultraestrutura , Transcriptoma/efeitos dos fármacos , Animais , Apoptose/genética , Caspase 3/metabolismo , Caspase 7/metabolismo , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Ventrículos do Coração/ultraestrutura , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/genética , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Contração Muscular/efeitos dos fármacos , Contração Muscular/genética , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Cadeias Leves de Miosina/sangue , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Trastuzumab , Troponina I/sangue
9.
J Acquir Immune Defic Syndr ; 63 Suppl 1: S26-31, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23673882

RESUMO

BACKGROUND: Disparities in the incidence and mortality of HIV/AIDS persist, challenging researchers, practitioners, and communities to develop improved strategies to reach vulnerable and marginalized populations. METHODS: The emerging field of Implementation Science, with its focus on context, external validity, and innovative design approaches, is well suited to respond to this challenge. We provide an overview of Implementation Science, including its frameworks, tools, and strategies, and how they can inform the response to HIV/AIDS. RESULTS: We summarize pioneering Implementation Science frameworks, and then present examples using newer models, including RE-AIM (Reach, Effectiveness/Efficacy, Adoption, Implementation, Maintenance) and the Evidence Integration Triangle, a framework for combining research and practice using participatory and adaptive processes in a multilevel context. CONCLUSIONS: Although still developing, the international field of Implementation Science can offer helpful perspectives for facilitating the more rapid integration of HIV/AIDS research, practice, and policy.


Assuntos
Pesquisa Biomédica , Infecções por HIV/prevenção & controle , HIV , Política de Saúde , Humanos , Modelos Teóricos , Pesquisa Translacional Biomédica
11.
BMC Med ; 6: 20, 2008 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-18647409

RESUMO

BACKGROUND: The modulation of gap junctional communication between tumor cells and between tumor and vascular endothelial cells during tumorigenesis and metastasis is complex. The notion of a role for loss of gap junctional intercellular communication in tumorigenesis and metastasis has been controversial. While some of the stages of tumorigenesis and metastasis, such as uncontrolled cell division and cellular detachment, would necessitate the loss of intercellular junctions, other stages, such as intravasation, endothelial attachment, and vascularization, likely require increased cell-cell contact. We hypothesized that, in this multi-stage scheme, connexin-43 is centrally involved as a cell adhesion molecule mediating metastatic tumor attachment to the pulmonary endothelium. METHODS: Tumor cell attachment to pulmonary vasculature, tumor growth, and connexin-43 expression was studied in metastatic lung tumor sections obtained after tail-vein injection into nude mice of syngeneic breast cancer cell lines, overexpressing wild type connexin-43 or dominant-negatively mutated connexin-43 proteins. High-resolution immunofluorescence microscopy and Western blot analysis was performed using a connexin-43 monoclonal antibody. Calcein Orange Red AM dye transfer by fluorescence imaging was used to evaluate the gap junction function. RESULTS: Adhesion of breast cancer cells to the pulmonary endothelium increased with cancer cells overexpressing connexin-43 and markedly decreased with cells expressing dominant-negative connexin-43. Upregulation of connexin-43 was observed in tumor cell-endothelial cell contact areas in vitro and in vivo, and in areas of intratumor blood vessels and in micrometastatic foci. CONCLUSION: Connexin-43 facilitates metastatic 'homing' by increasing adhesion of cancer cells to the lung endothelial cells. The marked upregulation of connexin-43 in tumor cell-endothelial cell contact areas, whether in preexisting 'homing' vessels or in newly formed tumor vessels, suggests that connexin-43 can serve as a potential marker of micrometastases and tumor vasculature and that it may play a role in the early incorporation of endothelial cells into small tumors as seeds for vasculogenesis.


Assuntos
Conexina 43/genética , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/patologia , Neoplasias Epiteliais e Glandulares/secundário , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Animais , Adesão Celular/genética , Linhagem Celular Tumoral , Conexina 43/biossíntese , Conexina 43/sangue , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Feminino , Junções Comunicantes/genética , Regulação Neoplásica da Expressão Gênica , Pulmão/patologia , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Mamárias Experimentais/irrigação sanguínea , Camundongos , Camundongos Nus , Mutação de Sentido Incorreto , Transplante de Neoplasias , Neoplasias Epiteliais e Glandulares/irrigação sanguínea , Neovascularização Patológica/sangue , Ratos , Transfecção
12.
Am J Physiol Lung Cell Mol Physiol ; 294(3): L419-30, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18065657

RESUMO

Endothelial progenitor cells (EPCs) have been isolated postnatally from bone marrow, blood, and both the intima and adventitia of conduit vessels. However, it is unknown whether EPCs can be isolated from the lung microcirculation. Thus we sought to determine whether the microvasculature possesses EPCs capable of de novo vasculogenesis. Rat pulmonary artery (PAEC) and microvascular (PMVEC) endothelial cells were isolated and selected by using a single-cell clonogenic assay. Whereas the majority of PAECs (approximately 60%) were fully differentiated, the majority of PMVECs (approximately 75%) divided, with approximately 50% of the single cells giving rise to large colonies (>2,000 cells/colony). These highly proliferative cells exhibited the capacity to reconstitute the entire proliferative hierarchy of PMVECs, unveiling the existence of resident microvascular endothelial progenitor cells (RMEPCs). RMEPCs expressed endothelial cell markers (CD31, CD144, endothelial nitric oxide synthase, and von Willenbrand factor) and progenitor cell antigens (CD34 and CD309) but did not express the leukocyte marker CD45. Consistent with their origin, RMEPCs interacted with Griffonia simplicifolia and displayed restrictive barrier properties. In vitro and in vivo Matrigel assays revealed that RMEPCs possess vasculogenic capacity, forming ultrastructurally normal de novo vessels. Thus the pulmonary microcirculation is enriched with EPCs that display vasculogenic competence while maintaining functional endothelial microvascular specificity.


Assuntos
Endotélio Vascular/citologia , Pulmão/irrigação sanguínea , Microcirculação/citologia , Neovascularização Fisiológica/fisiologia , Células-Tronco/fisiologia , Antígeno AC133 , Animais , Antígenos CD/análise , Antígenos CD34/análise , Caderinas/análise , Proliferação de Células , Glicoproteínas/análise , Antígenos Comuns de Leucócito/análise , Óxido Nítrico Sintase Tipo II/análise , Óxido Nítrico Sintase Tipo III , Peptídeos/análise , Fenótipo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Ratos , Telômero/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise
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