RESUMO

Atraumatic chest pain is a common emergency department (ED) presentation and the American College of Cardiology and American Heart Association recommends stress testing within 72 hours. The HEART score predicts major adverse cardiac events (MACE) in ED populations and does not require universal stress testing. An evaluation based solely on history, electrocardiography, and biomarkers, therefore, is an attractive approach to risk stratification in resource-limited settings. The HEART score has not been previously evaluated in a safety net hospital setting. We therefore implemented an interdisciplinary clinical care guideline utilizing the HEART score to stratify patients presenting to our inner-city hospital. During a 6-month study period, 1170 patients were evaluated (521 before and 649 after implementation). Among the 998 patients with confirmed follow-up 6-weeks after the index ED encounter, the prevalence of MACE (all-cause mortality, acute myocardial infarction, or coronary revascularization) was 0% [95% confidence interval (CI), 0%-1%] for low, 9% (95% CI, 7%-12%) for moderate, and 52% (95% CI, 39%-65%) for high-risk groups. Guideline implementation significantly increased admissions (+12%, 95% CI, 7%-17%) primarily in the moderate risk group (+38%, 95% CI, 29%-47%), but significantly decreased median ED length of stay (-37 minutes, 95% CI, 17-58). It also led to an increase in stress testing among moderate and high-risk patients (+10%, 95% CI, 0%-19%). In conclusion, the HEART score effectively stratified risk of MACE in a safety net population, improved evaluation consistency, and decreased ED length of stay. However, implementation was associated with an increase in hospitalizations and stress testing. Although the American Heart Association/American College of Cardiology guideline regarding atraumatic chest pain in the ED recommends universal noninvasive testing, the value of this approach, particularly in conjunction with the HEART score is uncertain in safety net hospitals. Further evaluation of the costs and clinical advantages of this approach are warranted.

Assuntos

RESUMO

BACKGROUND: Root and tuber crops are becoming more important for their high source of carbohydrates, next to cereals. Despite their commercial impact, there are significant knowledge gaps about the environmental and inherent regulation of storage root (SR) differentiation, due in part to the innate problems of studying storage roots and the lack of a suitable model system for monitoring storage root growth. The research presented here aimed to develop a reliable, low-cost effective system that enables the study of the factors influencing cassava storage root initiation and development. RESULTS: We explored simple, low-cost systems for the study of storage root biology. An aeroponics system described here is ideal for real-time monitoring of storage root development (SRD), and this was further validated using hormone studies. Our aeroponics-based auxin studies revealed that storage root initiation and development are adaptive responses, which are significantly enhanced by the exogenous auxin supply. Field and histological experiments were also conducted to confirm the auxin effect found in the aeroponics system. We also developed a simple digital imaging platform to quantify storage root growth and development traits. Correlation analysis confirmed that image-based estimation can be a surrogate for manual root phenotyping for several key traits. CONCLUSIONS: The aeroponic system developed from this study is an effective tool for examining the root architecture of cassava during early SRD. The aeroponic system also provided novel insights into storage root formation by activating the auxin-dependent proliferation of secondary xylem parenchyma cells to induce the initial root thickening and bulking. The developed system can be of direct benefit to molecular biologists, breeders, and physiologists, allowing them to screen germplasm for root traits that correlate with improved economic traits.