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Current therapies for the epilepsies only treat the symptoms, but do not prevent epileptogenesis (the process in which epilepsy develops). Many cellular responses during epileptogenesis are also common hallmarks of cellular senescence , which halts proliferation of damaged cells. Clearing senescent cells (SCs) restores function in several age-associated and neurodegenerative disease models. It is unknown whether SC accumulation contributes to epileptogenesis and associated cognitive impairments. To address this question, we used a mouse model of temporal lobe epilepsy (TLE) and characterized the senescence phenotype throughout epileptogenesis. SCs accumulated 2 weeks after SE and were predominantly microglia. We ablated SCs and reduced (and in some cases prevented) the emergence of spontaneous seizures and normalized cognitive function in mice. Suggesting that this is a translationally-relevant target we also found SC accumulation in resected hippocampi from patients with TLE. These findings indicate that SC ablation after an epileptogenic insult is a potential anti-epileptogenic therapy.
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Increased vulnerability to seizures in aging has been well documented both clinically and in various models of aging in epilepsy. Seizures can exacerbate cognitive decline that is already prominent in aging. Senescent cells are thought to contribute to cognitive impairment in aging and clearing senescent cells with senolytic drugs improves cognitive function in animal models. It remains unclear whether senescent cells render the aged brain vulnerable to seizures. Here, we demonstrate that prophylactic senolytic treatment with Dasatinib and Quercetin (D&Q) reduced both seizure severity and mortality in aged C57BL/6J mice. We subjected the D&Q and VEH-treated aged mice to spatial memory testing before and after an acute seizure insult, Status Epilepticus [SE], which leads to epilepsy development. We found that senolytic therapy improved spatial memory before injury, however, spatial memory was not rescued after SE. Senescence-related proteins p16 and senescence-associated ß-galactosidase were reduced in D&Q-treated aged mice. Our findings indicate that senescent cells increase seizure susceptibility in aging. Thus, prophylactically targeting senescent cells may prevent age-related seizure vulnerability.
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Camundongos Endogâmicos C57BL , Convulsões , Estado Epiléptico , Animais , Camundongos , Estado Epiléptico/tratamento farmacológico , Convulsões/tratamento farmacológico , Senoterapia/farmacologia , Senoterapia/uso terapêutico , Masculino , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Envelhecimento , Quercetina/farmacologia , Quercetina/uso terapêutico , Senescência Celular/efeitos dos fármacosRESUMO
PURPOSE OF REVIEW: To examine the effects and interactions between gut microbia and chronic pain. RECENT FINDINGS: The gut microbiome has been an area of interest in both the scientific and general audience due to a growing body of evidence suggesting its influence in a variety of health and disease states. Communication between the central nervous system (CNS) and gut microbiome is said to be bidirectional, in what is referred to as the gut-brain axis. Chronic pain is a prevalent costly personal and public health burden and so, there is a vested interest in devising safe and efficacious treatments. Numerous studies, many of which are animal studies, have been conducted to examine the gut microbiome's role in the pathophysiology of chronic pain states, such as neuropathy, inflammation, visceral pain, etc. As the understanding of this relationship grows, so does the potential for therapeutic targeting of the gut microbiome in chronic pain.
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Dor Crônica , Microbioma Gastrointestinal , Dor Visceral , Animais , Humanos , Microbioma Gastrointestinal/fisiologia , Dor Crônica/terapia , Sistema Nervoso Central , Inflamação , Dor Visceral/terapia , EncéfaloRESUMO
BACKGROUND: Cancer is common and disproportionately impacts older adults. Moreover, cancer care of older adults is complex, and the current Canadian cancer care system struggles to address all of the dimensions. In this project, our goal was to understand the barriers and facilitators to caring for older adults with cancer from perspectives of healthcare professionals and cancer care allies, which included community groups, seniors' centers, and other community-based supports. METHODS: In collaboration with a patient advisory board, we conducted focus groups and interviews with multiple local healthcare professionals and cancer care allies in British Columbia, Canada. We used a descriptive qualitative approach and conducted a thematic analysis using NVivo software. RESULTS: A total of 71 participants of various disciplines and cancer care allies participated. They identified both individual and system-level barriers. Priority system-level barriers for older adults included space and staffing constraints and disconnections within healthcare systems, and between healthcare practitioners and cancer care allies. Individual-level barriers relate to the complex health states of older adults, caregiver/support person needs, and the needs of an increasingly diverse population where English may not be a first or preferable language. CONCLUSIONS: This study identified key barriers and facilitators that demonstrate aligned priorities among a diverse group of healthcare practitioners and cancer care allies. In conjunction with perspectives from patients and caregivers, these findings will inform future improvements in cancer care. Namely, we emphasize the importance of connections among health systems and community networks, given the outpatient nature of cancer care and the needs of older adults.
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Pessoal de Saúde , Neoplasias , Humanos , Idoso , Colúmbia Britânica , Neoplasias/terapia , Redes Comunitárias , Grupos FocaisRESUMO
BACKGROUND: Selexipag is an oral prostacyclin receptor agonist, indicated for pulmonary arterial hypertension to delay disease progression and reduce the risk of pulmonary arterial hypertension-related hospitalization. SelexiPag: tHe usErs dRug rEgistry (NCT03278002) was a US-based, prospective, real-world registry of selexipag-treated patients. METHODS: Adults with pulmonary hypertension (enrolled 2016-2020) prescribed selexipag were followed for ≤18 months, with data collected at routine clinic visits. Patients were defined as newly or previously initiated if they had started selexipag ≤60 days or >60 days, respectively, before enrollment. RESULTS: The registry included 829 patients (430 newly initiated, 399 previously initiated; 759 with pulmonary arterial hypertension), of whom 55.6% were World Health Organization functional class (FC) 3/4; 57.3% were intermediate or high risk per Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) 2.0. In patients with pulmonary arterial hypertension, 18-month discontinuation rates for adverse events were 22.0%, 32.0%, and 11.9%, and 18-month survival rates were 89.4%, 84.2%, and 94.5% in the overall, newly, and previously initiated patient populations, respectively. From baseline to month 18, most patients had stable or improved FC and stable or improved REVEAL 2.0 risk category status. Discontinuation for adverse events, hospitalization, and survival were similar regardless of patients' individually tolerated selexipag maintenance dose. No new safety signals were identified. CONCLUSIONS: In this real-world analysis of patients initiating selexipag, most patients had stable or improved FC and REVEAL 2.0 risk category. Similar to the GRIPHON trial, outcomes with selexipag in this real-world study were comparable across maintenance dose strata, with no new safety signals.
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Acetamidas , Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Pirazinas , Adulto , Humanos , Hipertensão Arterial Pulmonar/tratamento farmacológico , Anti-Hipertensivos , Estudos Prospectivos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar Primária Familiar/tratamento farmacológicoRESUMO
Pulmonary arterial hypertension (PAH) is a rare, life-limiting disease. PAH registries provide real-world data that complement clinical trial data and inform treatment decisions. The TRIO comprehensive, integrated patient data repository (TRIO CIPDR), is an innovative US repository capturing data on contemporary patients diagnosed with pulmonary hypertension and receiving US Food and Drug Administration-approved PAH therapies. This repository uniquely combines clinical data from electronic medical records with the ability to track drug-prescription and drug-dispensing characteristics, and includes 946 adult patients with PAH (data collected January 2019 to December 2020) enrolled from nine representative US specialist tertiary care centers. Potentially eligible patients were identified based on dispensing data from specialty pharmacies. Hemodynamic and clinical data, as well as dispensing information on prescribed PAH medications, were provided by tertiary centers. At enrollment, 75% of patients were female, 67% were White, median age at PAH diagnosis was 53 years (median time from diagnosis to enrollment was 5 years), and 37% were obese. Comorbidity profiles were as expected for a PAH population, although the proportion with atrial fibrillation (34%) was higher than expected. Overall, 38% of patients had idiopathic PAH and 30% had connective tissue disease-related PAH. Among 917 patients receiving PAH-specific therapy, 40% were on monotherapy, 43% on dual therapy, and 17% on triple therapy. Longitudinal data from this repository will allow tracking of the PAH treatment journey in relation to clinical characteristics and outcomes.
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We previously identified a causal link between a rare patient mutation in DISC1 (disrupted-in-schizophrenia 1) and synaptic deficits in cortical neurons differentiated from isogenic patient-derived induced pluripotent stem cells (iPSCs). Here we find that transcripts related to phosphodiesterase 4 (PDE4) signaling are significantly elevated in human cortical neurons differentiated from iPSCs with the DISC1 mutation and that inhibition of PDE4 or activation of the cAMP signaling pathway functionally rescues synaptic deficits. We further generated a knock-in mouse line harboring the same patient mutation in the Disc1 gene. Heterozygous Disc1 mutant mice exhibit elevated levels of PDE4s and synaptic abnormalities in the brain, and social and cognitive behavioral deficits. Pharmacological inhibition of the PDE4 signaling pathway rescues these synaptic, social and cognitive behavioral abnormalities. Our study shows that patient-derived isogenic iPSC and humanized mouse disease models are integral and complementary for translational studies with a better understanding of underlying molecular mechanisms.
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Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Inibidores da Fosfodiesterase 4/farmacologia , Esquizofrenia/genética , Animais , Comportamento Animal/efeitos dos fármacos , Córtex Cerebral/fisiologia , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Masculino , Camundongos Mutantes , Mutação , Neurônios/efeitos dos fármacos , Rolipram/farmacologia , Esquizofrenia/patologia , Sinapses/efeitos dos fármacos , Sinapses/fisiologiaRESUMO
The concept of chaotic advection is a novel approach that has the potential to overcome some of the challenges associated with mixing of reagents that commonly occur when injection based in situ treatment techniques are used. The rotated potential mixing (RPM) flow system is one configuration which has been theorized to achieve chaotic advection in porous media, and enhance reagent mixing by periodically re-oriented dipole pumping at a series of radial wells. Prior to field implementation of chaotic advection, the selection of an RPM flow protocol will likely require a numerical model that can adequately represent groundwater flow within the zone of interest. As expected, the hydraulic conductivity (K) field is the most critical input requirement for the selected groundwater flow model. Hydraulic tomography (HT) is an innovative characterization approach that has shown potential to provide information on a K field. In this investigation, we explored whether the same well system required to invoke chaotic advection can also be applied in a HT analysis, and evaluated the use of the generated K tomogram for the selection of RPM flow parameters that can enhance reagent mixing. A series of dipole pumping tests were conducted within an area of interest as defined by the limits of the circular network of eight injection/extraction wells used to invoke chaotic advection. Hydraulic head data collected from independent dipole pumping tests were used in an inverse model to perform steady-state hydraulic tomography (SSHT) analysis to generate a K tomogram. Both the K tomogram and an effective parameter approach (i.e., a single K value assigned across the entire spatial domain as determined by single well pumping and slug tests) produced estimates of hydraulic head that closely resembled those observed due to the relative homogeneous nature of the aquifer and the small spatial scale of the area of interest. In contrast, particle tracking results showed that incorporating a heterogeneous K field significantly enhanced the spatial distribution of particle trajectories indicative of reagent mixing. These findings support the hypothesis that the same well system used to invoke chaotic advection can be combined with SSHT analysis as a viable site characterization tool for delineating the spatial variability of K. Incorporating this K tomogram in a groundwater flow model with a particle tracking engine can be used as a design tool to aid in the selection of a site-specific RPM flow protocol to achieve enhanced reagent mixing.
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Água Subterrânea , Modelos Teóricos , Porosidade , Tomografia , Movimentos da Água , Poços de ÁguaRESUMO
Although a 14-day treatment course with amoxicillin is in wide clinical usage to treat early Lyme disease, only a few published studies exist to validate its efficacy and safety, with none in the United States. In this study, we reviewed the records of 24 prospectively followed adult patients with erythema migrans who were prescribed a 14-day course of amoxicillin, 500â¯mg 3 times daily. Treatment with amoxicillin was well tolerated and uniformly successful in resolving the erythema migrans skin lesion and in preventing the development of an objective neurologic, cardiac, or rheumatologic manifestation. Although the study was relatively small and only involved a single center, the findings provide additional evidence that a 14-day course of 500â¯mg amoxicillin given 3 times per day is highly effective therapy for patients with early Lyme disease.
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Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Eritema Migrans Crônico/tratamento farmacológico , Adulto , Idoso , Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Estados UnidosRESUMO
The presence of inherited chromosomally integrated human herpesvirus 6 (ciHHV-6) in hematopoietic cell transplant (HCT) donors or recipients confounds molecular testing for HHV-6 reactivation, which occurs in 30 to 50% of transplants. Here we describe a multiplex droplet digital PCR clinical diagnostic assay that concurrently distinguishes between HHV-6 species (A or B) and identifies inherited ciHHV-6. By applying this assay to recipient post-HCT plasma and serum samples, we demonstrated reactivation of HHV-6B in 25% (4/16 recipients) of HCT recipients with donor- or recipient-derived inherited ciHHV-6A, underscoring the need for diagnostic testing for HHV-6 infection even in the presence of ciHHV-6.
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Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 6/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Roseolovirus/diagnóstico , Transplantados , Ativação Viral , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/fisiologia , Humanos , Plasma/virologiaRESUMO
Cyclic AMP-response element-binding protein (CREB) is a transcription factor implicated in growth factor-dependent cell proliferation and survival, glucose homeostasis, spermatogenesis, circadian rhythms, and synaptic plasticity associated with memory. To study the phenotype of CREB overexpression in vivo, we generated CREB transgenic (TG) mice in which a myeloid specific hMRP8 promoter drives CREB expression. CREB TG mice developed spontaneous skin abscesses more frequently than wild type (WT) mice. To understand the role of CREB in myeloid function and innate immunity, chemokine expression in bone marrow derived macrophages (BMDMs) from CREB TG mice were compared with BMDMs from WT mice. Our results demonstrated decreased Keratinocyte-derived cytokine (KC) in CREB TG BMDMs but not TNFα protein production in response to lipid A (LPA). In addition, mRNA expression of KC and IL-1ß (Interleukin)-1ß was decreased in CREB TG BMDMs; however, there was no difference in the mRNA expression of TNFα, MCP-1, IL-6 and IL-12p40. The mRNA expression of IL-1RA and IL-10 was decreased in response to LPA. Nuclear factor kappa B (NFκB) expression and a subset of its target genes were upregulated in CREB TG mouse BMDMs. Although neutrophil migration was the same in both CREB TG and WT mice, Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was significantly increased in neutrophils from CREB TG mice. Taken together, CREB overexpression in myeloid cells results in increased abscess formation in vivo and aberrant cytokine and chemokine response, and neutrophil function in vitro.
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Abscesso/etiologia , Quimiocinas/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Citocinas/metabolismo , Células Mieloides/patologia , Neutrófilos/patologia , Abscesso/diagnóstico , Animais , Proliferação de Células , Sobrevivência Celular , Quimiocinas/genética , Citocinas/genética , Feminino , Queratinócitos/metabolismo , Queratinócitos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Mieloides/metabolismo , Neutrófilos/metabolismo , Ativação TranscricionalRESUMO
The cAMP response element-binding protein (CREB) is a nuclear transcription factor that is critical for normal and neoplastic hematopoiesis. Previous studies have demonstrated that CREB is a proto-oncogene whose overexpression promotes cellular proliferation in hematopoietic cells. Transgenic mice that overexpress CREB in myeloid cells develop a myeloproliferative disease with splenomegaly and aberrant myelopoiesis. However, CREB overexpressing mice do not spontaneously develop acute myeloid leukemia. In this study, we used retroviral insertional mutagenesis to identify genes that accelerate leukemia in CREB transgenic mice. Our mutagenesis screen identified several integration sites, including oncogenes Gfi1, Myb, and Ras. The Sox4 transcription factor was identified by our screen as a gene that cooperates with CREB in myeloid leukemogenesis. We show that the transduction of CREB transgenic mouse bone marrow cells with a Sox4 retrovirus increases survival and self-renewal of cells in vitro. Furthermore, leukemic blasts from the majority of acute myeloid leukemia patients have higher CREB, phosphorylated CREB, and Sox 4 protein expression. Sox4 transduction of mouse bone marrow cells results in increased expression of CREB target genes. We also demonstrate that CREB is a direct target of Sox4 by chromatin immunoprecipitation assays. These results indicate that Sox4 and CREB cooperate and contribute to increased proliferation of hematopoietic progenitor cells.
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Transformação Celular Neoplásica/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Células Mieloides/metabolismo , Fatores de Transcrição SOXC/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proliferação de Células , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Feminino , Células HL-60 , Humanos , Células K562 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células Mieloides/citologia , Fosforilação/fisiologia , Gravidez , Proto-Oncogene Mas , Retroviridae/genéticaRESUMO
Due to stable incidence and improved survival rates, there are an increasing number of patients living with HIV/AIDS in the USA. Although highly effective, current antiretroviral therapies are associated with a variety of side effects. The role side effects play on health outcomes has not been fully examined. The current study assessed the association of medication side effects with (1) self-assessed health status; (2) work productivity and activity impairment; and (3) healthcare resource utilization. Data were from a cross-sectional patient-reported survey fielded in the USA using a dual methodology of Internet and paper questionnaires. A total of 953 patients living with HIV/AIDS who were currently taking a medication for their condition were included in the analyses. The most frequent side effects reported by patients were fatigue (70.72%), diarrhea (62.96%), insomnia (58.97%), dizziness (52.78%), neuropathy (52.68%), joint pain (52.36%), nausea (51.63%), and abdominal pain (50.37%). The presence of each side effect was associated with reduced self-assessed health status, increased productivity loss, increased activity impairment, and increased healthcare resource use. Controlling for CD4 cell counts in regression modeling did little to diminish the impact of side effects. Although not all side effects were associated with all outcomes, every side effect was associated with worse health status, some measure of increased work productivity loss, and/or some measure of increased healthcare resource use. Patients are living longer with HIV and, therefore, spending a greater length of time on treatment. The results of the current study suggest that many of these patients are experiencing a wide array of side effects from these therapies. These side effects have demonstrated a profound association with self-assessed health, work productivity, and healthcare resource use. Improved management of these side effects or development of treatments with a better side effect profile may have a substantial humanistic and economic benefit.
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Síndrome da Imunodeficiência Adquirida/complicações , Fármacos Anti-HIV/efeitos adversos , Fadiga/induzido quimicamente , Recursos em Saúde/estatística & dados numéricos , Nível de Saúde , Dor/induzido quimicamente , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Trabalho , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/psicologia , Adulto , Fármacos Anti-HIV/administração & dosagem , Contagem de Linfócito CD4 , Estudos Transversais , Eficiência , Fadiga/epidemiologia , Fadiga/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/epidemiologia , Dor/psicologia , Qualidade de Vida , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Inquéritos e Questionários , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Translating the extraordinary scientific and technological advances occurring in medical research laboratories into care for patients in communities throughout the country has been a major challenge. One contributing factor has been the relative absence of community practitioners from the US biomedical research enterprise. Identifying and addressing the barriers that prevent their participation in research should help bridge the gap between basic research and practice to improve quality of care for all Americans. METHODS: We interviewed over 200 clinicians and other healthcare stakeholders from 2004 through 2005 to develop a conceptual framework and set of strategies for engaging a stable cadre of community clinicians in a clinical research program. RESULTS: Lack of engagement of community practitioners, lack of necessary infrastructure, and the current misalignment of financial incentives and research participation emerged as the three primary barriers to community clinician research participation. Although every effort was made to learn key motivators for engagement in clinical research from interviewees, we did not observe their behavior and self-report by clinicians does not always track with their behavior. CONCLUSIONS: A paradigm shift involving acknowledgement of the value of clinicians in the context of community research, establishment of a stable infrastructure to support a cohort of clinicians across time and research studies, and realignment of incentives to encourage participation in clinical research is required.
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Papel do Médico , Pesquisa Translacional Biomédica/métodos , Pesquisa Biomédica/organização & administração , Health Insurance Portability and Accountability Act , Humanos , Disseminação de Informação , Entrevistas como Assunto , Mecanismo de Reembolso , Características de Residência , Pesquisa Translacional Biomédica/economia , Confiança , Estados Unidos , Recursos HumanosRESUMO
BACKGROUND: New National Institutes of Health policies call for expansion of practice-based research to improve the clinical research enterprise and facilitate dissemination of evidence-based medicine. OBJECTIVE: This paper describes organizational strategies that influence clinicians' decisions to participate in clinical research. DESIGN: We reviewed the literature and interviewed over 200 clinicians and stakeholders. RESULTS: The most common barriers to community clinician participation in clinical research relate to beliefs that clinical research is too burdensome and has little benefit for the participating clinician or patient. We identified a number of approaches healthcare organizations can use to encourage clinicians to participate in research, including an outreach campaign to promote the benefits of clinical research; selection of study topics of interest to clinicians; establishment and enforcement of a set of research principles valuing the clinician and patient; development of a transparent schedule of reimbursement for research tasks; provision of technological and technical assistance to practices as needed; and promotion of a sense of community among clinicians involved in practice-based research. CONCLUSIONS: Many types of existing healthcare organizations could provide the technical and intellectual assistance community clinicians need to participate in clinical research. Multiple approaches are possible.
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Pesquisa Participativa Baseada na Comunidade , Tomada de Decisões , Medicina Baseada em Evidências , Humanos , Entrevistas como AssuntoRESUMO
BACKGROUND: The National Institutes of Health has called for expansion of practice-based research to improve the clinical research enterprise. METHODS: This paper presents a model for the reorganization of clinical research to foster long-term participation by community clinicians.Based on the literature and interviews with clinicians and other stakeholders, we posited a model, conducted further interviews to test the viability of the model, and further adapted it. RESULTS: We propose a three-dimensional system of checks and balances to support community clinicians using research support organizations, community outreach, a web-based registry of clinicians and studies, web-based training services, quality audits, and a feedback mechanism for clinicians engaged in research. CONCLUSIONS: The proposed model is designed to offer a systemic mechanism to address current barriers that prevent clinicians from participation in research. Transparent mechanisms to guarantee the safety of patients and the integrity of the research enterprise paired with efficiencies and economies of scale are maintained by centralizing some of the functions. Assigning other responsibilities to more local levels assures flexibility with respect to the size of the clinician networks and the changing needs of researchers.