An Official American Thoracic Society Research Statement: Implementation Science in Pulmonary, Critical Care, and Sleep Medicine.

BACKGROUND: Many advances in health care fail to reach patients. Implementation science is the study of novel approaches to mitigate this evidence-to-practice gap. METHODS: The American Thoracic Society (ATS) created a multidisciplinary ad hoc committee to develop a research statement on implementation science in pulmonary, critical care, and sleep medicine. The committee used an iterative consensus process to define implementation science and review the use of conceptual frameworks to guide implementation science for the pulmonary, critical care, and sleep community and to explore how professional medical societies such as the ATS can promote implementation science. RESULTS: The committee defined implementation science as the study of the mechanisms by which effective health care interventions are either adopted or not adopted in clinical and community settings. The committee also distinguished implementation science from the act of implementation. Ideally, implementation science should include early and continuous stakeholder involvement and the use of conceptual frameworks (i.e., models to systematize the conduct of studies and standardize the communication of findings). Multiple conceptual frameworks are available, and we suggest the selection of one or more frameworks on the basis of the specific research question and setting. Professional medical societies such as the ATS can have an important role in promoting implementation science. Recommendations for professional societies to consider include: unifying implementation science activities through a single organizational structure, linking front-line clinicians with implementation scientists, seeking collaborations to prioritize and conduct implementation science studies, supporting implementation science projects through funding opportunities, working with research funding bodies to set the research agenda in the field, collaborating with external bodies responsible for health care delivery, disseminating results of implementation science through scientific journals and conferences, and teaching the next generation about implementation science through courses and other media. CONCLUSIONS: Implementation science plays an increasingly important role in health care. Through support of implementation science, the ATS and other professional medical societies can work with other stakeholders to lead this effort.

Kinase domain mutants of Bcr-Abl exhibit altered transformation potency, kinase activity, and substrate utilization, irrespective of sensitivity to imatinib.

Kinase domain (KD) mutations of Bcr-Abl interfering with imatinib binding are the major mechanism of acquired imatinib resistance in patients with Philadelphia chromosome-positive leukemia. Mutations of the ATP binding loop (p-loop) have been associated with a poor prognosis. We compared the transformation potency of five common KD mutants in various biological assays. Relative to unmutated (native) Bcr-Abl, the ATP binding loop mutants Y253F and E255K exhibited increased transformation potency, M351T and H396P were less potent, and the performance of T315I was assay dependent. The transformation potency of Y253F and M351T correlated with intrinsic Bcr-Abl kinase activity, whereas the kinase activity of E255K, H396P, and T315I did not correlate with transforming capabilities, suggesting that additional factors influence transformation potency. Analysis of the phosphotyrosine proteome by mass spectroscopy showed differential phosphorylation among the mutants, a finding consistent with altered substrate specificity and pathway activation. Mutations in the KD of Bcr-Abl influence kinase activity and signaling in a complex fashion, leading to gain- or loss-of-function variants. The drug resistance and transformation potency of mutants may determine the outcome of patients on therapy with Abl kinase inhibitors.

Patient and Clinician Characteristics Associated with Adherence. A Cohort Study of Veterans with Incidental Pulmonary Nodules.

RATIONALE: Many patients are diagnosed with small pulmonary nodules for which professional societies recommend subsequent imaging surveillance. Adherence to these guidelines involves many steps from both clinicians and patients but has not been well studied. OBJECTIVES: In a health care setting with a nodule tracking system, we evaluated the association of communication processes and distress with patient and clinician adherence to recommended follow up and Fleischner Society guidelines, respectively. METHODS: We conducted a prospective, longitudinally assessed, cohort study of patients with incidentally detected nodules who received care at one Veterans Affairs Medical Center. We measured patient-centered communication with the Consultation Care Measure and distress with the Impact of Event Scale. We abstracted data regarding participant adherence to clinician recommendations (defined as receiving the follow-up scan within 30 d of the recommended date) and clinician adherence to Fleischner guidelines (defined as planning the follow-up scan within 30 d of the recommended interval) from the electronic medical record. We measured associations of communication and distress with adherence using multivariable-adjusted generalized estimating equations. MEASUREMENTS AND MAIN RESULTS: Among 138 veterans, 39% were nonadherent at least once during follow up. Clinicians were nonadherent to Fleischner guidelines for 27% of follow-up scans. High-quality communication (adjusted odds ratio, 3.65; P = 0.02) and distress (adjusted odds ratio, 0.38; P = 0.02) were associated with increased and decreased participant adherence, respectively. Neither was associated with clinician adherence. CONCLUSIONS: Patients and clinicians often do not adhere to nodule follow-up recommendations. Interventions designed to improve communication quality and decrease distress may also improve patient adherence to nodule follow-up recommendations.

Intensive care unit scoring systems outperform emergency department scoring systems for mortality prediction in critically ill patients: a prospective cohort study.

BACKGROUND: Multiple scoring systems have been developed for both the intensive care unit (ICU) and the emergency department (ED) to risk stratify patients and predict mortality. However, it remains unclear whether the additional data needed to compute ICU scores improves mortality prediction for critically ill patients compared to the simpler ED scores. METHODS: We studied a prospective observational cohort of 227 critically ill patients admitted to the ICU directly from the ED at an academic, tertiary care medical center. We compared Acute Physiology and Chronic Health Evaluation (APACHE) II, APACHE III, Simplified Acute Physiology Score (SAPS) II, Modified Early Warning Score (MEWS), Rapid Emergency Medicine Score (REMS), Prince of Wales Emergency Department Score (PEDS), and a pre-hospital critical illness prediction score developed by Seymour et al. (JAMA 2010, 304(7):747-754). The primary endpoint was 60-day mortality. We compared the receiver operating characteristic (ROC) curves of the different scores and their calibration using the Hosmer-Lemeshow goodness-of-fit test and visual assessment. RESULTS: The ICU scores outperformed the ED scores with higher area under the curve (AUC) values (p = 0.01). There were no differences in discrimination among the ED-based scoring systems (AUC 0.698 to 0.742; p = 0.45) or among the ICU-based scoring systems (AUC 0.779 to 0.799; p = 0.60). With the exception of the Seymour score, the ED-based scoring systems did not discriminate as well as the best-performing ICU-based scoring system, APACHE III (p = 0.005 to 0.01 for comparison of ED scores to APACHE III). The Seymour score had a superior AUC to other ED scores and, despite a lower AUC than all the ICU scores, was not significantly different than APACHE III (p = 0.09). When data from the first 24 h in the ICU was used to calculate the ED scores, the AUC for the ED scores improved numerically, but this improvement was not statistically significant. All scores had acceptable calibration. CONCLUSIONS: In contrast to prior studies of patients based in the emergency department, ICU scores outperformed ED scores in critically ill patients admitted from the emergency department. This difference in performance seemed to be primarily due to the complexity of the scores rather than the time window from which the data was derived.

In vitro efficacy of combined treatment depends on the underlying mechanism of resistance in imatinib-resistant Bcr-Abl-positive cell lines.

Imatinib mesylate (Gleevec, formerly STI571) is an effective therapy for all stages of chronic myelogenous leukemia (CML). While responses in chronic-phase CML are generally durable, resistance develops in many patients with advanced disease. We evaluated novel antileukemic agents for their potential to overcome resistance in various imatinib-resistant cell lines. Using cell proliferation assays, we investigated whether different mechanisms of resistance to imatinib would alter the efficacy of arsenic trioxide (As2O3) or 5-aza-2-deoxycytidine (decitabine) alone and in combination with imatinib. Our results indicate that resistance to imatinib induced by Bcr-Abl overexpression or by engineered expression of clinically relevant Bcr-Abl mutants does not induce cross-resistance to As2O3 or decitabine. Combined treatment with these agents and imatinib is beneficial in cell lines that have residual sensitivity to imatinib monotherapy, with synergistic growth inhibition achieved only at doses of imatinib that overcome resistance. In some imatinib-resistant cell lines, combination treatments that use low doses of imatinib lead to antagonism. Apoptosis studies suggest that this can be explained in part by the reduced proapoptotic activity of imatinib in resistant cell lines. These data underline the importance of resistance testing and provide a rational approach for dose-adjusted administration of imatinib when combined with other agents.

Inhibition of wild-type and mutant Bcr-Abl by AP23464, a potent ATP-based oncogenic protein kinase inhibitor: implications for CML.

The deregulated, oncogenic tyrosine kinase Bcr-Abl causes chronic myeloid leukemia (CML). Imatinib mesylate (Gleevec, STI571), a Bcr-Abl kinase inhibitor, selectively inhibits proliferation and promotes apoptosis of CML cells. Despite the success of imatinib mesylate in the treatment of CML, resistance is observed, particularly in advanced disease. The most common imatinib mesylate resistance mechanism involves Bcr-Abl kinase domain mutations that impart varying degrees of drug insensitivity. AP23464, a potent adenosine 5'-triphosphate (ATP)-based inhibitor of Src and Abl kinases, displays antiproliferative activity against a human CML cell line and Bcr-Abl-transduced Ba/F3 cells (IC(50) = 14 nM; imatinib mesylate IC(50) = 350 nM). AP23464 ablates Bcr-Abl tyrosine phosphorylation, blocks cell cycle progression, and promotes apoptosis of Bcr-Abl-expressing cells. Biochemical assays with purified glutathione S transferase (GST)-Abl kinase domain confirmed that AP23464 directly inhibits Abl activity. Importantly, the low nanomolar cellular and biochemical inhibitory properties of AP23464 extend to frequently observed imatinib mesylate-resistant Bcr-Abl mutants, including nucleotide binding P-loop mutants Q252H, Y253F, E255K, C-terminal loop mutant M351T, and activation loop mutant H396P. AP23464 was ineffective against mutant T315I, an imatinib mesylate contact residue. The potency of AP23464 against imatinib mesylate-refractory Bcr-Abl and its distinct binding mode relative to imatinib mesylate warrant further investigation of AP23464 for the treatment of CML.