RESUMEN
Late gadolinium enhancement (LGE) is a widely used magnetic resonance imaging method for assessing cardiac disease. However, the relationship between different LGE signal thresholds and microscopic tissue staining images is unclear. In this study, we performed cardiovascular MRI on myocardial infarction (MI) model rats and evaluated the relationship between LGE with different signal thresholding methods and tissue staining images. We prepared 16 rats that underwent MRI 14-18 days following a surgery to create an MI model. We captured cine and LGE images of the cardiac short-axis and longitudinal two- and four-chamber views. The mean ± 2SD, ± 3SD, and ± 5SD of the pixel values in the non-infarcted area were defined as the LGE area. We compared areas of Sirius red staining, determined by the color tone, with their respective LGE areas at end-diastole and end-systole. We observed that the LGE area calculated as the mean ± 2SD of the non-infarcted area at end-diastole demonstrated a significant positive correlation with the area of Sirius red staining (Pearson's correlation coefficient in both: 0.81 [p < 0.01]). Therefore, the LGE area calculated as the mean ± 2SD of the non-infarcted area at end-diastole best reflected the MI area in tissue staining.
Asunto(s)
Medios de Contraste , Modelos Animales de Enfermedad , Gadolinio , Imagen por Resonancia Magnética , Infarto del Miocardio , Animales , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/patología , Ratas , Imagen por Resonancia Magnética/métodos , Masculino , Coloración y Etiquetado/métodos , Miocardio/patología , Ratas Sprague-DawleyRESUMEN
Community forests (CFs) have been widely established in tropical countries as a tool to achieve forest conservation. Many studies have shown that CFs can contribute to the reduction of deforestation, yet studies that evaluate the contribution of CFs to reducing forest degradation and facilitating forest recovery remain scarce. We investigated the ability of CFs to prevent deforestation and forest degradation and to facilitate forest recovery by using a country-scale longitudinal tree canopy cover and forest cover data set in Cambodia. We found that CFs can prevent both forest degradation and deforestation, but we did not observe a forest recovery effect. We also found that recently established CFs are not effective for forest conservation compared with older CFs. We conclude that, to date, CFs are an effective forest conservation tool; however, this does not necessarily mean that new CFs will be as effective as established ones.