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SET domain proteins methylate specific lysines on proteins, triggering stimulation or repression of downstream processes. Twenty-nine SET domain proteins have been identified in Leishmania donovani through sequence annotations. This study initiates the first investigation into these proteins. We find LdSET7 is predominantly cytosolic. Although not essential, set7 deletion slows down promastigote growth and hypersensitizes the parasite to hydroxyurea-induced G1/S arrest. Intriguingly, set7-nulls survive more proficiently than set7+/+ parasites within host macrophages, suggesting that LdSET7 moderates parasite response to the inhospitable intracellular environment. set7-null in vitro promastigote cultures are highly tolerant to hydrogen peroxide (H2O2)-induced stress, reflected in their growth pattern, and no detectable DNA damage at H2O2 concentrations tested. This is linked to reactive oxygen species levels remaining virtually unperturbed in set7-nulls in response to H2O2 exposure, contrasting to increased reactive oxygen species in set7+/+ cells under similar conditions. In analyzing the cell's ability to scavenge hydroperoxides, we find peroxidase activity is not upregulated in response to H2O2 exposure in set7-nulls. Rather, constitutive basal levels of peroxidase activity are significantly higher in these cells, implicating this to be a factor contributing to the parasite's high tolerance to H2O2. Higher levels of peroxidase activity in set7-nulls are coupled to upregulation of tryparedoxin peroxidase transcripts. Rescue experiments using an LdSET7 mutant suggest that LdSET7 methylation activity is critical to the modulation of the cell's response to oxidative environment. Thus, LdSET7 tunes the parasite's behavior within host cells, enabling the establishment and persistence of infection without eradicating the host cell population it needs for survival.
Assuntos
Leishmania donovani , Estresse Oxidativo , Peroxidases , Proteínas de Protozoários , Animais , Peróxido de Hidrogênio/metabolismo , Leishmania donovani/genética , Leishmania donovani/metabolismo , Peroxidases/genética , Peroxidases/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Domínios PR-SETRESUMO
BACKGROUND: Invasive width, the distance between the most peripheral invasive melanoma cells on the section where Breslow thickness (BT) was measured, was recently identified as a prognostic feature. It is unclear whether a routine measurement is justified, given that macroscopic width is already included in many melanoma histopathology reports and may itself be a prognostic feature. This study sought to investigate this. METHODS: A retrospective cohort of 718 melanoma patients in which macroscopic width had been stated in the original histopathology report was used. Survival analysis was performed. RESULTS: Macroscopic and invasive widths were positively correlated (p < 0.001). Invasive width was typically smaller than the paired macroscopic width (median difference 3.7 mm, p < 0.001), a difference seen across all T groups. Both macroscopic and invasive widths were significantly associated with melanoma survival in Kaplan-Meier analysis, including overall survival, but invasive width survival curves were more widely separated. Both were significantly associated with outcome after correction for BT in Cox proportional hazards regression, but the models containing invasive width had a substantially better fit. CONCLUSIONS: This study shows that both macroscopic and invasive widths have prognostic values, but confirms that the latter is superior. It supports further investigation of this feature's prognostic value.
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Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Melanoma Maligno CutâneoRESUMO
OBJECTIVE: Diagnosis often evolves over time, involves uncertainty, and is vulnerable to errors. We examined pediatric clinicians' perspectives on communicating diagnostic uncertainty to patients' parents and how this occurs. DESIGN: We conducted semi-structured interviews, which were audiotaped, transcribed, and analyzed using content analysis. Two researchers independently coded transcripts and then discussed discrepancies to reach consensus. SETTING: A purposive sample of pediatric clinicians at two large academic medical institutions in Texas. PARTICIPANTS: Twenty pediatric clinicians participated: 18 physicians, 2 nurse practitioners; 7 males, 13 females; 7 inpatient, 11 outpatient, and 2 practicing in mixed settings; with 0-16 years' experience post-residency. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Pediatric clinician perspectives on communication of diagnostic uncertainty. RESULTS: Pediatric clinicians commonly experienced diagnostic uncertainty and most were comfortable seeking help and discussing with colleagues. However, when communicating uncertainty to parents, clinicians used multiple considerations to adjust the degree to which they communicated. Considerations included parent characteristics (education, socioeconomic status, emotional response, and culture) and strength of parent-clinician relationships. Communication content included setting expectations, explaining the diagnostic process, discussing most relevant differentials, and providing reassurance. Responses to certain parent characteristics, however, were variable. For example, some clinicians were more open to discussing diagnostic uncertainty with more educated parents- others were less. CONCLUSIONS: While pediatric clinicians are comfortable discussing diagnostic uncertainty with colleagues, how they communicate uncertainty to parents appears variable. Parent characteristics and parent-clinician relationships affect extent of communication and content discussed. Development and implementation of optimal strategies for managing and communicating diagnostic uncertainty can improve the diagnostic process.
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Comunicação , Diagnóstico Diferencial , Profissionais de Enfermagem Pediátrica/psicologia , Pediatras/psicologia , Incerteza , Feminino , Humanos , Masculino , Pais/psicologia , Relações Profissional-Família , Pesquisa Qualitativa , TexasRESUMO
BACKGROUND: Patients can provide valuable information missing from traditional sources of safety data, thus adding new insights about factors that lead to preventable harm. In this study, researchers determined associations between patient-reported contributory factors and patient-reported harms experienced after an adverse event (AE). METHODS: A secondary analysis was conducted of a national sample of patient-reported AEs (surgical, medication, diagnostic, and hospital-acquired infection) gathered through an online questionnaire between January 2010 and February 2016. Generalized logit multivariable regression was used to assess the association between patient-reported contributory factors and patient-reported harms (grouped as nonphysical harm only, physical harm only, physical harm and emotional or financial harm, and all three harms) and adjusted for patient and AE characteristics. RESULTS: One third of patients (32.6%) reported experiencing all three harms, 27.3% reported physical harms and one additional harm, 25.5% reported physical harms only, and 14.7% reported nonphysical harms only. Patients reporting all three harms were 2.5 times more likely to have filed a report with a responsible authority (95% confidence interval [CI]â¯=â¯1.23-5.01) and 3.3 times more likely to have also experienced a surgical complication (95% CIâ¯=â¯1.42-7.51). Odds of reporting problems related to communication between clinician and patients/families or clinician-related behavioral issues was 13% higher in those experiencing all three harm types (95% CIâ¯=â¯1.07-1.19). CONCLUSION: Patients' experiences are important to identify safety issues and reduce harm and should be included in patient safety measurement and improvement activities. These findings underscore the need for policy and practice changes to identify, address, and support harmed patients.
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Pessoal de Saúde , Segurança do Paciente , Comunicação , Humanos , Medidas de Resultados Relatados pelo Paciente , Inquéritos e QuestionáriosRESUMO
The medical record continues to be one of the most useful and accessible sources of information to examine the diagnostic process. However, medical record review studies of diagnostic errors have often used subjective judgments and found low inter-rater agreement among reviewers when determining the presence or absence of diagnostic error. In our previous work, we developed a structured data-collection instrument, called the Safer Dx Instrument, consisting of objective criteria to improve the accuracy of assessing diagnostic errors in primary care. This paper proposes recommendations on how clinicians and health care organizations could use the Revised Safer Dx Instrument in identifying and understanding missed opportunities to make correct and timely diagnoses. The instrument revisions addressed both methodological and implementation issues identified during initial use and included refinements to the instrument to allow broader application across all health care settings. In addition to leveraging knowledge from piloting the instrument in several health care settings, we gained insights from multiple researchers who had used the instrument in studies involving emergency care, inpatient care and intensive care unit settings. This allowed us to enhance and extend the scope of this previously validated data collection instrument. In this paper, we describe the refinement process and provide recommendations for application and use of the Revised Safer Dx Instrument across a broad range of health care settings. The instrument can help users identify potential diagnostic errors in a standardized way for further analysis and safety improvement efforts as well as provide data for clinician feedback and reflection. With wider adoption and use by clinicians and health systems, the Revised Safer Dx Instrument could help propel the science of measuring and reducing diagnostic errors forward.
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Coleta de Dados/instrumentação , Erros de Diagnóstico/estatística & dados numéricos , Testes Diagnósticos de Rotina/métodos , Segurança do Paciente/normas , Atenção à Saúde/organização & administração , Atenção à Saúde/tendências , Erros de Diagnóstico/prevenção & controle , Humanos , Prontuários Médicos/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de SaúdeRESUMO
RATIONALE, AIMS AND OBJECTIVES: Diagnostic uncertainty is common in primary care. Because it is challenging to measure, there is inadequate scientific understanding of diagnostic decision-making during uncertainty. Our objective was to understand how diagnostic uncertainty was documented in the electronic health record (EHR) and explore a strategy to retrospectively identify it using clinician documentation. METHODS: We reviewed the literature to identify documentation language that could identify both direct expression and indirect inference of diagnostic uncertainty and designed an instrument to facilitate record review. Direct expression included clinician's use of question marks, differential diagnoses, symptoms as diagnosis, or vocabulary such as "probably, maybe, likely, unclear or unknown," while describing the diagnosis. Indirect inference included absence of documented diagnosis at the end of the visit, ordering of multiple consultations or diagnostic tests to resolve diagnostic uncertainty, and use of suspended judgement, test of treatment, and risk-averse disposition. Two physician-reviewers independently reviewed notes on a sample of outpatient visits to identify diagnostic uncertainty at the end of the visit. Documented Ninth Revision of the International Classification of Diseases (ICD-9) diagnosis codes and note quality were assessed. RESULTS: Of 389 patient records reviewed, 218 had evidence of diagnostic activity and were included. In 156 visits (71.6%), reviewers identified clinicians who experienced diagnostic uncertainty with moderate inter-reviewer agreement (81.7%; Cohen's kappa: 0.609). Most cases (125, 80.1%) showed evidence of both direct expression and indirect inference. Uncertainty was directly expressed in 139 (89.1%) cases, most commonly by using symptoms as diagnosis (98, 62.8%), and inferred in 144 (92.3%). In more than 1/3 of visits (58, 37.2%), diagnostic uncertainty was recorded inappropriately using ICD-9 codes. CONCLUSIONS: While current diagnosis coding mechanisms (ICD-9 and ICD-10) are unable to capture uncertainty, our study finds that review of EHR documentation can help identify diagnostic uncertainty with moderate reliability. Better measurement and understanding of diagnostic uncertainty could help inform strategies to improve the safety and efficiency of diagnosis.
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Erros de Diagnóstico , Registros Eletrônicos de Saúde , Atenção Primária à Saúde , Incerteza , Erros de Diagnóstico/estatística & dados numéricos , Humanos , Auditoria Médica , Estudos RetrospectivosRESUMO
Objective: Mobile applications for improving diagnostic decision making often lack clinical evaluation. We evaluated if a mobile application improves generalist physicians' appropriate laboratory test ordering and diagnosis decisions and assessed if physicians perceive it as useful for learning. Methods: In an experimental, vignette study, physicians diagnosed 8 patient vignettes with normal prothrombin times (PT) and abnormal partial thromboplastin times (PTT). Physicians made test ordering and diagnosis decisions for 4 vignettes using each resource: a mobile app, PTT Advisor, developed by the Centers for Disease Control and Prevention (CDC)'s Clinical Laboratory Integration into Healthcare Collaborative (CLIHC); and usual clinical decision support. Then, physicians answered questions regarding their perceptions of the app's usefulness for diagnostic decision making and learning using a modified Kirkpatrick Training Evaluation Framework. Results: Data from 368 vignettes solved by 46 physicians at 7 US health care institutions show advantages for using PTT Advisor over usual clinical decision support on test ordering and diagnostic decision accuracy (82.6 vs 70.2% correct; P < .001), confidence in decisions (7.5 vs 6.3 out of 10; P < .001), and vignette completion time (3:02 vs 3:53 min.; P = .06). Physicians reported positive perceptions of the app's potential for improved clinical decision making, and recommended it be used to address broader diagnostic challenges. Conclusions: A mobile app, PTT Advisor, may contribute to better test ordering and diagnosis, serve as a learning tool for diagnostic evaluation of certain clinical disorders, and improve patient outcomes. Similar methods could be useful for evaluating apps aimed at improving testing and diagnosis for other conditions.