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1.
Cancer Cell ; 42(5): 723-726, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38701793

RESUMO

Advances in biomedical research require a robust physician scientist workforce. Despite being equally successful at securing early career awards from the NIH as men, women MD-PhD physician scientists are less likely to serve as principal investigators on mid- and later careers awards. Here, we discuss the causes of gender disparities in academic medicine, the implications of losing highly trained women physician scientists, and the institutional and systemic changes needed to sustain this pool of talented investigators.


Assuntos
Pesquisa Biomédica , Médicas , Pesquisadores , Humanos , Feminino , Médicas/estatística & dados numéricos , Masculino , Escolha da Profissão , Estados Unidos , Sexismo , Mobilidade Ocupacional , Médicos , Distinções e Prêmios
2.
Shock ; 59(2): 232-238, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36669229

RESUMO

ABSTRACT: Introduction: Trauma alters the immune response in numerous ways, affecting both the innate and adaptive responses. Macrophages play an important role in inflammation and wound healing following injury. We hypothesize that macrophages mobilize from the circulation to the site of injury and secondary sites after trauma, with a transition from proinflammatory (M1) shortly after trauma to anti-inflammatory (M2) at later time points. Methods: C57Bl6 mice (n = 6/group) underwent a polytrauma model using cardiac puncture/hemorrhage, pseudofemoral fracture, and liver crush injury. The animals were killed at several time points: uninjured, 24 h, and 7 days. Peripheral blood mononuclear cells, spleen, liver nonparenchymal cells, and lung were harvested, processed, and stained for flow cytometry. Macrophages were identified as CD68 + ; M1 macrophages were identified as iNOS + ; M2 macrophages as arginase 1 + . Results: We saw a slight presence of M1 macrophages at baseline in peripheral blood mononuclear cells (6.6%), with no significant change at 24 h and 7 days after polytrauma. In contrast, the spleen has a larger population of M1 macrophages at baseline (27.7%), with levels decreasing at 24 h and 7 days after trauma (20.6% and 12.6%, respectively). A similar trend is seen in the lung where at baseline 14.9% of CD68 + macrophages are M1, with subsequent continual decrease reaching 8.7% at 24 h and 4.4% at 7 days after polytrauma. M1 macrophages in the liver represent 14.3% of CD68 + population in the liver nonparenchymal cells at baseline. This percentage increases to 20.8% after trauma and decreases at 7 days after polytrauma (13.4%). There are few M2 macrophages in circulating peripheral blood mononuclear cells and in spleen at baseline and after trauma. The percentage of M2 macrophages in the lungs remains constant after trauma (7.2% at 24 h and 9.2% at 7 days). In contrast, a large proportion of M2 macrophages are seen in the liver at baseline (36.0%). This percentage trends upward and reaches 45.6% acutely after trauma and drops to 21.4% at 7 days. The phenotypic changes in macrophages seen in the lungs did not correlate with a functional change in the ability of the macrophages to perform oxidative burst, with an increase from 2.0% at baseline to 22.1% at 7 days after polytrauma ( P = 0.0258). Conclusion: Macrophage phenotypic changes after polytrauma are noted, especially with a decrease in the lung M1 phenotype and a short-term increase in the M2 phenotype in the liver. However, macrophage function as measured by oxidative burst increased over the time course of trauma, which may signify a change in subset polarization after injury not captured by the typical macrophage phenotypes.


Assuntos
Leucócitos Mononucleares , Traumatismo Múltiplo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Pulmão/metabolismo , Traumatismo Múltiplo/metabolismo
3.
Brain Pathol ; 33(3): e13118, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36161399

RESUMO

Chronic inflammation is frequently invoked as a mechanism of neurodegeneration and yet inflammatory cell infiltrates are seldom seen in brains of these disorders. Different disciplines utilize different technologies and methodologies to describe what is immunologically defined as the innate immune response (IIR). We examined murine models of the human neurodegenerative disease Aicardi-Goutières Syndrome, where an IIR is initiated by aberrant RNA metabolism secondary to a mutation in adenosine deaminase acting on RNA gene (ADAR1). We previously showed that these mice demonstrated a deficit in RNA editing that lead to MDA-5 mediated RNA sensing pathway activation of the IIR with massive interferon stimulated gene transcription and translation. As early as 2 weeks of age, in situ hybridization demonstrated that different central nervous system (CNS) cell lineages expressed very high levels of distinct interferon stimulated genes (ISGs) in the absence of interferon and absence of immune cell infiltrates. We have expanded these studies to more completely describe the breadth of ISG expression systemically and in CNS using double label in situ hybridization. Within the CNS aberrant ISG expression was mostly limited to neurons, microglia, ependyma, choroid plexus, and endothelial cells with little expression in oligodendroglia and astrocytes except for STAT1. Wild type controls showed a similar pattern of ISG expression but only in aged mice and at levels minimally detectable by in situ hybridization. Despite months of elevated ISG expression in mutant mice, there was essentially no inflammatory infiltrate, no interferon production and minimal glial reaction. Histomorphological neurodegenerative pathology of ventricular dilatation and deep gray matter mineralization were evident in mutant mice 8-13 months of age but this did not show a spatial relationship to ISG expression. This IIR without immune cell infiltration leads to neurodegeneration through non-canonical pathways that may accentuate normal aging pathways.


Assuntos
Células Endoteliais , Doenças Neurodegenerativas , Humanos , Animais , Camundongos , Células Endoteliais/metabolismo , Modelos Animais de Doenças , Doenças Neurodegenerativas/metabolismo , Encéfalo/metabolismo , Imunidade Inata , RNA/metabolismo , Adenosina Desaminase/metabolismo
4.
J Neuroinflammation ; 19(1): 285, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457126

RESUMO

BACKGROUND: Aicardi-Goutières syndrome (AGS) is a severe neurodegenerative disease with clinical features of early-onset encephalopathy and progressive loss of intellectual abilities and motor control. Gene mutations in seven protein-coding genes have been found to be associated with AGS. However, the causative role of these mutations in the early-onset neuropathogenesis has not been demonstrated in animal models, and the mechanism of neurodegeneration of AGS remains ambiguous. METHODS: Via CRISPR/Cas-9 technology, we established a mutant mouse model in which a genetic mutation found in AGS patients at the ADAR1 coding gene (Adar) loci was introduced into the mouse genome. A mouse model carrying double gene mutations encoding ADAR1 and MDA-5 was prepared using a breeding strategy. Phenotype, gene expression, RNA sequencing, innate immune pathway activation, and pathologic studies including RNA in situ hybridization (ISH) and immunohistochemistry were used for characterization of the mouse models to determine potential disease mechanisms. RESULTS: We established a mouse model bearing a mutation in the catalytic domain of ADAR1, the D1113H mutation found in AGS patients. With this mouse model, we demonstrated a causative role of this mutation for the early-onset brain injuries in AGS and determined the signaling pathway underlying the neuropathogenesis. First, this mutation altered the RNA editing profile in neural transcripts and led to robust IFN-stimulated gene (ISG) expression in the brain. By ISH, the brains of mutant mice showed an unusual, multifocal increased expression of ISGs that was cell-type dependent. Early-onset astrocytosis and microgliosis and later stage calcification in the deep white matter areas were observed in the mutant mice. Brain ISG activation and neuroglial reaction were completely prevented in the Adar D1113H mutant mice by blocking RNA sensing through deletion of the cytosolic RNA receptor MDA-5. CONCLUSIONS: The Adar D1113H mutation in the ADAR1 catalytic domain results in early-onset and MDA5-dependent encephalopathy with IFN pathway activation in the mouse brain.


Assuntos
Lesões Encefálicas , Doenças Neurodegenerativas , Animais , Camundongos , Domínio Catalítico , Encéfalo , Mutação/genética , Modelos Animais de Doenças , RNA , Adenosina Desaminase/genética
5.
JCI Insight ; 7(6)2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35315356

RESUMO

MD-PhD trainees constitute an important source of physician-scientists. Persistence on this challenging path is facilitated by success in garnering independent (R grant) support from the NIH. Published research tracks academic appointments and global R01 success for MD-PhD trainees but has not included information on future funding success of individual MD-PhD predoctoral grant holders. Here, we used data from the NIH RePORTER database to identify and track the funding trajectory of physician-scientists who received predoctoral grant support through the F30 mechanism, which is specific for dual-degree candidates. Male and female F30 awardees did not differ in their success in garnering K (postdoctoral training) grants, but, among F30 grant awardees, men were 2.6 times more likely than women to receive R funding. These results underscore the need for analysis of factors that contribute to the disproportionate loss of NIH-supported female physician-scientists between the predoctoral F30 and the independent R grant-supported stages.


Assuntos
Pesquisa Biomédica , Médicos , Bases de Dados Factuais , Feminino , Humanos , Masculino
6.
J Neuroinflammation ; 18(1): 169, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34332594

RESUMO

BACKGROUND: Aicardi-Goutières syndrome (AGS) is a severe infant or juvenile-onset autoimmune disease characterized by inflammatory encephalopathy with an elevated type 1 interferon-stimulated gene (ISG) expression signature in the brain. Mutations in seven different protein-coding genes, all linked to DNA/RNA metabolism or sensing, have been identified in AGS patients, but none of them has been demonstrated to activate the IFN pathway in the brain of an animal. The molecular mechanism of inflammatory encephalopathy in AGS has not been well defined. Adenosine Deaminase Acting on RNA 1 (ADAR1) is one of the AGS-associated genes. It carries out A-to-I RNA editing that converts adenosine to inosine at double-stranded RNA regions. Whether an AGS-associated mutation in ADAR1 activates the IFN pathway and causes autoimmune pathogenesis in the brain is yet to be determined. METHODS: Mutations in the ADAR1 gene found in AGS patients were introduced into the mouse genome via CRISPR/Cas9 technology. Molecular activities of the specific p.K999N mutation were investigated by measuring the RNA editing levels in brain mRNA substrates of ADAR1 through RNA sequencing analysis. IFN pathway activation in the brain was assessed by measuring ISG expression at the mRNA and protein level through real-time RT-PCR and Luminex assays, respectively. The locations in the brain and neural cell types that express ISGs were determined by RNA in situ hybridization (ISH). Potential AGS-related brain morphologic changes were assessed with immunohistological analysis. Von Kossa and Luxol Fast Blue staining was performed on brain tissue to assess calcification and myelin, respectively. RESULTS: Mice bearing the ADAR1 p.K999N were viable though smaller than wild type sibs. RNA sequencing analysis of neuron-specific RNA substrates revealed altered RNA editing activities of the mutant ADAR1 protein. Mutant mice exhibited dramatically elevated levels of multiple ISGs within the brain. RNA ISH of brain sections showed selective activation of ISG expression in neurons and microglia in a patchy pattern. ISG-15 mRNA was upregulated in ADAR1 mutant brain neurons whereas CXCL10 mRNA was elevated in adjacent astroglia. No calcification or gliosis was detected in the mutant brain. CONCLUSIONS: We demonstrated that an AGS-associated mutation in ADAR1, specifically the p.K999N mutation, activates the IFN pathway in the mouse brain. The ADAR1 p.K999N mutant mouse replicates aspects of the brain interferonopathy of AGS. Neurons and microglia express different ISGs. Basal ganglia calcification and leukodystrophy seen in AGS patients were not observed in K999N mutant mice, indicating that development of the full clinical phenotype may need an additional stimulus besides AGS mutations. This mutant mouse presents a robust tool for the investigation of AGS and neuroinflammatory diseases including the modeling of potential "second hits" that enable severe phenotypes of clinically variable diseases.


Assuntos
Adenosina Desaminase/genética , Doenças Autoimunes do Sistema Nervoso/genética , Encéfalo/imunologia , Imunidade Inata/genética , Mutação , Malformações do Sistema Nervoso/genética , Animais , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Autoimunes do Sistema Nervoso/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Camundongos , Malformações do Sistema Nervoso/imunologia , Malformações do Sistema Nervoso/metabolismo , Edição de RNA
8.
JCI Insight ; 6(3)2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33351788

RESUMO

Human lung adenocarcinoma (LUAD) in current or former smokers exhibits a high tumor mutational burden (TMB) and distinct mutational signatures. Syngeneic mouse models of clinically relevant smoking-related LUAD are lacking. We established and characterized a tobacco-associated, transplantable murine LUAD cell line, designated FVBW-17, from a LUAD induced by the tobacco carcinogen 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone in the FVB/N mouse strain. Whole-exome sequencing of FVBW-17 cells identified tobacco-associated KrasG12D and Trp53 mutations and a similar mutation profile to that of classic alkylating agents with a TMB greater than 500. FVBW-17 cells transplanted subcutaneously, via tail vein, and orthotopically generated tumors that were histologically similar to human LUAD in FVB/N mice. FVBW-17 tumors expressed programmed death ligand 1 (PD-L1), were infiltrated with CD8+ T cells, and were responsive to anti-PD-L1 therapy. FVBW-17 cells were also engineered to express green fluorescent protein and luciferase to facilitate detection and quantification of tumor growth. Distant metastases to lung, spleen, liver, and kidney were observed from subcutaneously transplanted tumors. This potentially novel cell line is a robust representation of human smoking-related LUAD biology and provides a much needed preclinical model in which to test promising new agents and combinations, including immune-based therapies.


Assuntos
Adenocarcinoma de Pulmão/induzido quimicamente , Antígeno B7-H1/metabolismo , Carcinógenos/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Nitrosaminas/toxicidade , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Animais , Antígeno B7-H1/antagonistas & inibidores , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Masculino , Camundongos , Mutação , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Fumaça/efeitos adversos , Nicotiana/toxicidade , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
9.
Acad Med ; 95(9): 1373-1381, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32079926

RESUMO

The University of Pittsburgh School of Medicine Physician Scientist Training Program (PSTP) is a 5-year medical student training program designed to prepare the next generation of MD-only physician-scientists engaging in preclinical research. This article provides an overview of the program, including the novel longitudinal structure and competency goals, which facilitate success and persistence in a laboratory-based physician-scientist career. The authors present data on 81 medical students accepted to the program from academic year 2007-2008 through 2018-2019. Extrinsic outcomes, such as publications, grant funding, and residency matching, indicate that PSTP trainees have actively generated research deliverables. A majority of eligible PSTP trainees have earned Howard Hughes Medical Institute Medical Research Fellow funding. PSTP students have produced a mean of 1.6 first-authored publications (median, 1.0) and a mean of 5.1 total publications (median, 4.0) while in medical school and have authored 0.9 publications per year as residents/fellows, excluding internship. Nearly 60% of PSTP students (26/46) have matched to top-10 National Institutes of Health-funded residency programs in their specialty (based on Blue Ridge Institute rankings). PSTP alumni are twice as likely as their classmates to match into research-heavy departments and to publish first-authored papers. Results of a 2018 program evaluation survey indicate that intrinsic outcomes, such as confidence in research skills, significantly correlate with extrinsic outcomes. The program continues to evolve to maximize both scientific agency and career navigation skills in participants. This medical student PSTP model has potential to expand the pool of physician-scientist researchers in preclinical research beyond the capacity of dedicated MD-PhD and postgraduate training programs.


Assuntos
Pesquisa Biomédica/educação , Educação de Pós-Graduação , Educação Médica , Internato e Residência , Pennsylvania , Médicos , Faculdades de Medicina
10.
Eur J Heart Fail ; 20(6): 1031-1038, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29761861

RESUMO

AIM: There is limited information on the outcomes after primary prevention implantable cardioverter-defibrillator (ICD) implantation in patients with heart failure (HF) and diabetes. This analysis evaluates the effectiveness of a strategy of ICD plus medical therapy vs. medical therapy alone among patients with HF and diabetes. METHODS AND RESULTS: A patient-level combined-analysis was conducted from a combined dataset that included four primary prevention ICD trials of patients with HF or severely reduced ejection fractions: Multicenter Automatic Defibrillator Implantation Trial I (MADIT I), MADIT II, Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE), and Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). In total, 3359 patients were included in the analysis. The primary outcome of interest was all-cause death. Compared with patients without diabetes (n = 2363), patients with diabetes (n = 996) were older and had a higher burden of cardiovascular risk factors. During a median follow-up of 2.6 years, 437 patients without diabetes died (178 with ICD vs. 259 without) and 280 patients with diabetes died (128 with ICD vs. 152 without). ICDs were associated with a reduced risk of all-cause mortality among patients without diabetes [hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.46-0.67] but not among patients with diabetes (HR 0.88, 95% CI 0.7-1.12; interaction P = 0.015). CONCLUSION: Among patients with HF and diabetes, primary prevention ICD in combination with medical therapy vs. medical therapy alone was not significantly associated with a reduced risk of all-cause death. Further studies are needed to evaluate the effectiveness of ICDs among patients with diabetes.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Diabetes Mellitus/epidemiologia , Insuficiência Cardíaca/terapia , Prevenção Primária/métodos , Volume Sistólico/fisiologia , Comorbidade/tendências , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Feminino , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
11.
Am Heart J ; 191: 21-29, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28888266

RESUMO

BACKGROUND: Primary prevention implantable cardioverter defibrillator (ICD) reduce all-cause mortality by reducing sudden cardiac death. There are conflicting data regarding whether patients with more advanced heart failure derive ICD benefit owing to the competing risk of nonsudden death. METHODS: We performed a patient-level meta-analysis of New York Heart Association (NYHA) class II/III heart failure patients (left ventricular ejection fraction ≤35%) from 4 primary prevention ICD trials (MADIT-I, MADIT-II, DEFINITE, SCD-HeFT). Bayesian-Weibull survival regression models were used to assess the impact of NYHA class on the relationship between ICD use and mortality. RESULTS: Of the 2,763 patients who met study criteria, 68% (n=1,867) were NYHA II and 52% (n=1,435) were randomized to an ICD. In a multivariable model including all study patients, the ICD reduced mortality (hazard ratio [HR] 0.65, 95% posterior credibility interval [PCI]) 0.40-0.99). The interaction between NYHA class and the ICD on mortality was significant (posterior probability of no interaction=.036). In models including an interaction term for the NYHA class and ICD, the ICD reduced mortality among NYHA class II patients (HR 0.55, PCI 0.35-0.85), and the point estimate suggested reduced mortality in NYHA class III patients (HR 0.76, PCI 0.48-1.24), although this was not statistically significant. CONCLUSIONS: Primary prevention ICDs reduce mortality in NYHA class II patients and trend toward reducing mortality in the heterogeneous group of NYHA class III patients. Improved risk stratification tools are required to guide patient selection and shared decision making among NYHA class III primary prevention ICD candidates.


Assuntos
Cardiologia , Morte Súbita Cardíaca , Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Prevenção Primária/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sociedades Médicas , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Saúde Global , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Humanos , New York , Taxa de Sobrevida/tendências
12.
Circ Cardiovasc Qual Outcomes ; 8(2): 179-86, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25669833

RESUMO

BACKGROUND: The impact of patient age on the risks of death or rehospitalization after primary prevention implantable cardioverter-defibrillator (ICD) placement is uncertain. METHODS AND RESULTS: Data from 5 major ICD trials were merged: the Multicenter Automatic Defibrillator Implantation Trial I (MADIT-I), the Multicenter UnSustained Tachycardia Trial (MUSTT), the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II), the Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation Trial (DEFINITE), and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). Median age at enrollment was 62 (interquartile range 53-70) years. Compared with their younger counterparts, older patients had a greater burden of comorbid illness. In unadjusted exploratory analyses, ICD recipients were less likely to die than nonrecipients in all age groups: among patients aged <55 years: hazard ratio 0.48, 95% posterior credible interval 0.33 to 0.69; among patients aged 55 to 64 years: hazard ratio 0.69, 95% posterior credible interval 0.53 to 0.90; among patients aged 65 to 74 years: hazard ratio 0.67, 95% posterior credible interval, 0.53 to 0.85; and among patients aged ≥75 years: hazard ratio 0.54, 95% posterior credible interval 0.37 to 0.78. Sample sizes were limited among patients aged ≥75 years. In adjusted Bayesian-Weibull modeling, point estimates indicate ICD efficacy persists but is attenuated with increasing age. There was evidence of an interaction between age and ICD treatment on survival (two-sided posterior tail probability of no interaction <0.01). Using an adjusted Bayesian logistic regression model, there was no evidence of an interaction between age and ICD treatment on rehospitalization (two-sided posterior tail probability of no interaction 0.44). CONCLUSIONS: In this analysis, the survival benefit of the ICD exists but is attenuated with increasing age. The latter finding may be because of the higher burden of comorbid illness, competing causes of death, or limited sample size of older patients. There was no evidence that age modifies the association between ICD treatment and rehospitalization.


Assuntos
Cardiomiopatias/terapia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Prevenção Primária/métodos , Fatores Etários , Idoso , Teorema de Bayes , Cardiomiopatias/diagnóstico , Cardiomiopatias/mortalidade , Cardiomiopatias/fisiopatologia , Distribuição de Qui-Quadrado , Ensaios Clínicos como Assunto , Comorbidade , Morte Súbita Cardíaca/etiologia , Cardioversão Elétrica/efeitos adversos , Cardioversão Elétrica/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
JACC Heart Fail ; 2(6): 623-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25306452

RESUMO

OBJECTIVES: The aim of this study was to determine if the benefit of implantable cardioverter-defibrillators (ICDs) is modulated by medical comorbidity. BACKGROUND: Primary prevention ICDs improve survival in patients at risk for sudden cardiac death. Their benefit in patients with significant comorbid illness has not been demonstrated. METHODS: Original, patient-level datasets from MADIT I (Multicenter Automatic Defibrillator Implantation Trial I), MADIT II, DEFINITE (Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation), and SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) were combined. Patients in the combined population (N = 3,348) were assessed with respect to the following comorbidities: smoking, pulmonary disease, diabetes, peripheral vascular disease, atrial fibrillation, ischemic heart disease, and chronic kidney disease. The primary outcome was overall mortality, using the hazard ratio (HR) of time to death for patients receiving an ICD versus no ICD by extent of medical comorbidity, and adjusted for age, sex, race, left ventricular ejection fraction, use of antiarrhythmic drugs, beta-blockers, and angiotensin-converting enzyme inhibitors. RESULTS: Overall, 25% of patients (n = 830) had <2 comorbid conditions versus 75% (n = 2,518) with significant comorbidity (≥2). The unadjusted hazard of death for patients with an ICD versus no ICD was significantly lower, but this effect was less for patients with ≥2 comorbidities (unadjusted HR: 0.71; 95% confidence interval: 0.61 to 0.84) compared with those with <2 comorbidities (unadjusted HR: 0.59; 95% confidence interval: 0.40 to 0.87). After adjustment, the benefit of an ICD decreased with increasing number of comorbidities (p = 0.004). CONCLUSIONS: Patients with extensive comorbid medical illnesses may experience less benefit from primary prevention ICDs than those with less comorbidity; implantation should be carefully considered in sick patients. Further study of ICDs in medically complex patients is warranted.


Assuntos
Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Morte Súbita Cardíaca/prevenção & controle , Feminino , Insuficiência Cardíaca/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Prevenção Primária , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Volume Sistólico , Resultado do Tratamento
14.
Am J Kidney Dis ; 64(1): 32-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24518128

RESUMO

BACKGROUND: The benefit of a primary prevention implantable cardioverter-defibrillator (ICD) among patients with chronic kidney disease is uncertain. STUDY DESIGN: Meta-analysis of patient-level data from randomized controlled trials. SETTING & POPULATION: Patients with symptomatic heart failure and left ventricular ejection fraction<35%. SELECTION CRITERIA FOR STUDIES: From 7 available randomized controlled studies with patient-level data, we selected studies with available data for important covariates. Studies without patient-level data for baseline estimated glomerular filtration rate (eGFR) were excluded. INTERVENTION: Primary prevention ICD versus usual care effect modification by eGFR. OUTCOMES: Mortality, rehospitalizations, and effect modification by eGFR. RESULTS: We included data from the Multicenter Automatic Defibrillator Implantation Trial I (MADIT-I), MADIT-II, and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). 2,867 patients were included; 36.3% had eGFR<60 mL/min/1.73m2. Kaplan-Meier estimate of the probability of death during follow-up was 43.3% for 1,334 patients receiving usual care and 35.8% for 1,533 ICD recipients. After adjustment for baseline differences, there was evidence that the survival benefit of ICDs in comparison to usual care depends on eGFR (posterior probability for null interaction P<0.001). The ICD was associated with survival benefit for patients with eGFR≥60 mL/min/1.73 m2 (adjusted HR, 0.49; 95% posterior credible interval, 0.24-0.95), but not for patients with eGFR<60 mL/min/1.73 m2 (adjusted HR, 0.80; 95% posterior credible interval, 0.40-1.53). eGFR did not modify the association between the ICD and rehospitalizations. LIMITATIONS: Few patients with eGFR<30 mL/min/1.73 m2 were available. Differences in trial-to-trial measurement techniques may lead to residual confounding. CONCLUSIONS: Reductions in baseline eGFR decrease the survival benefit associated with the ICD. These findings should be confirmed by additional studies specifically targeting patients with varying eGFRs.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Prevenção Primária , Insuficiência Renal Crônica/complicações , Idoso , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Renal Crônica/fisiopatologia , Fatores de Risco
16.
J Biomed Inform ; 52: 141-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24333875

RESUMO

Underspecified user needs and frequent lack of a gold standard reference are typical barriers to technology evaluation. To address this problem, this paper presents a two-phase evaluation framework involving usability experts (phase 1) and end-users (phase 2). In phase 1, a cross-system functionality alignment between expert-derived user needs and system functions was performed to inform the choice of "the best available" comparison system to enable a cognitive walkthrough in phase 1 and a comparative effectiveness evaluation in phase 2. During phase 2, five quantitative and qualitative evaluation methods are mixed to assess usability: time-motion analysis, software log, questionnaires - System Usability Scale and the Unified Theory of Acceptance of Use of Technology, think-aloud protocols, and unstructured interviews. Each method contributes data for a unique measure (e.g., time motion analysis contributes task-completion-time; software log contributes action transition frequency). The measures are triangulated to yield complementary insights regarding user-perceived ease-of-use, functionality integration, anxiety during use, and workflow impact. To illustrate its use, we applied this framework in a formative evaluation of a software called Integrated Model for Patient Care and Clinical Trials (IMPACT). We conclude that this mixed-methods evaluation framework enables an integrated assessment of user needs satisfaction and user-perceived usefulness and usability of a novel design. This evaluation framework effectively bridges the gap between co-evolving user needs and technology designs during iterative prototyping and is particularly useful when it is difficult for users to articulate their needs for technology support due to the lack of a baseline.


Assuntos
Pesquisa Biomédica , Informática Médica , Avaliação das Necessidades , Ensaios Clínicos como Assunto , Estudos de Avaliação como Assunto , Humanos
17.
AMIA Jt Summits Transl Sci Proc ; 2014: 109-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25954586

RESUMO

User needs understanding is critical for developing useful and usable clinical research decision support. Existing methods largely depend on self-reporting and often fail to elicit implicit or fine-grained user needs. We hypothesized that functional software would address this problem by presenting to users existing technology while simultaneously encouraging users to optimize workflow. Using clinical research visit scheduling as an example, we used a piece of software under development that was called IMPACT to reveal user needs iteratively. The identified user needs explained why most clinical research coordinators still rely on paper to schedule clinical research visits. The common user needs themes such as information completeness for software to be useful may generalize to other clinical decision support. This paper contributes valuable firsthand knowledge about user needs for decision support for clinical research visit scheduling among clinical research coordinators and a generalizable methodology for collecting and analyzing software usage data to inform user needs elicitation.

18.
AMIA Jt Summits Transl Sci Proc ; 2014: 116-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25954587

RESUMO

Despite the proliferation of research networking systems (RNS), their value and usage remains unknown. This study aims to characterize the temporal usage of an RNS, Columbia University Scientific Profiles (CUSP), and to inform the designs of general RNSs. We installed a free usage logging service, Google Analytics, on CUSP and applied time series analysis to compare the usage patterns of the two modes of CUSP: restricted (authenticated) and open access. More users searched by person names than by topics, although the latter enables in-depth vertical search of co-author or co-investigator networks for grants or publications. The open-access mode received more page views but less average time spent on each page than the restricted access mode. The numbers of unique users and searches have increased over the time. This study contributes a trend analysis framework for understanding the usage of RNSs and early knowledge of the usage of an open-access RNS.

19.
Am Heart J ; 166(4): 744-52, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24093856

RESUMO

BACKGROUND: Although left ventricular ejection fraction (LVEF) is the primary determinant for sudden cardiac death (SCD) risk stratification, in isolation, LVEF is a sub-optimal risk stratifier. We assessed whether a multi-marker strategy would provide more robust SCD risk stratification than LVEF alone. METHODS: We collected patient-level data (n = 3355) from 6 studies assessing the prognostic utility of microvolt T-wave alternans (MTWA) testing. Two thirds of the group was used for derivation (n = 2242) and one-third for validation (n = 1113). The discriminative capacity of the multivariable model was assessed using the area under the receiver-operating characteristic curve (c-index). The primary endpoint was SCD at 24 months. RESULTS: In the derivation cohort, 59 patients experienced SCD by 24 months. Stepwise selection suggested that a model based on 3 parameters (LVEF, coronary artery disease and MTWA status) provided optimal SCD risk prediction. In the derivation cohort, the c-index of the model was 0.817, which was significantly better than LVEF used as a single variable (0.637, P < .001). In the validation cohort, 36 patients experienced SCD by 24 months. The c-index of the model for predicting the primary endpoint was again significantly better than LVEF alone (0.774 vs 0.671, P = .020). CONCLUSIONS: A multivariable model based on presence of coronary artery disease, LVEF and MTWA status provides significantly more robust SCD risk prediction than LVEF as a single risk marker. These findings suggest that multi-marker strategies based on different aspects of the electro-anatomic substrate may be capable of improving primary prevention implantable cardioverter-defibrillator treatment algorithms.


Assuntos
Morte Súbita Cardíaca , Prevenção Primária , Medição de Risco/métodos , Taquicardia Ventricular/terapia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Técnicas Eletrofisiológicas Cardíacas , Humanos , Taquicardia Ventricular/complicações , Taquicardia Ventricular/mortalidade
20.
J Biomed Inform ; 46(4): 642-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23684593

RESUMO

We describe a clinical research visit scheduling system that can potentially coordinate clinical research visits with patient care visits and increase efficiency at clinical sites where clinical and research activities occur simultaneously. Participatory Design methods were applied to support requirements engineering and to create this software called Integrated Model for Patient Care and Clinical Trials (IMPACT). Using a multi-user constraint satisfaction and resource optimization algorithm, IMPACT automatically synthesizes temporal availability of various research resources and recommends the optimal dates and times for pending research visits. We conducted scenario-based evaluations with 10 clinical research coordinators (CRCs) from diverse clinical research settings to assess the usefulness, feasibility, and user acceptance of IMPACT. We obtained qualitative feedback using semi-structured interviews with the CRCs. Most CRCs acknowledged the usefulness of IMPACT features. Support for collaboration within research teams and interoperability with electronic health records and clinical trial management systems were highly requested features. Overall, IMPACT received satisfactory user acceptance and proves to be potentially useful for a variety of clinical research settings. Our future work includes comparing the effectiveness of IMPACT with that of existing scheduling solutions on the market and conducting field tests to formally assess user adoption.


Assuntos
Agendamento de Consultas , Pesquisa Biomédica , Ensaios Clínicos como Assunto , Atenção à Saúde/organização & administração , Aprendizagem , Modelos Organizacionais , Assistência ao Paciente , Algoritmos , Privacidade
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