Conditions for late gadolinium enhancement MRI in myocardial infarction model rats that better reflect microscopic tissue staining

Ueda J., Kurata H., Ota M., et al. Conditions for late gadolinium enhancement MRI in myocardial infarction model rats that better reflect microscopic tissue staining. Scientific Reports 14, 18308 (2024); https://doi.org/10.1038/s41598-024-69540-y.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

Single domain growth and charge ordering of epitaxial YbFe2O4 films

YbFe2O4 is a charge-ordered ferroelectric that exhibits coupling between magnetization and electric polarization near room temperature and crystallizes in a rhombohedral structure (R3¯m). This study presents an attempt to fabricate stoichiometric and epitaxial YbFe2O4-δ films with a nearly single-domain structure using an RF magnetron sputtering method. The (0001)-oriented epitaxial films of YbFe2O4-δ on YSZ (111) substrates via reactive sputtering method exhibited clear three-fold symmetry normal to the substrate without the formation of twin domains rotated by 60°. The oxygen stoichiometry of the epitaxial YbFe2O4-δ was improved by controlling an oxygen partial pressure (PO2) during the deposition. The films showed a sharp ferrimagnetic transition, and the transition temperature (TN) increased linearly to approximately 245 K with decreasing PO2. The magnitude of magnetization of the obtained films was comparable to that of bulk single crystals. Further, the electron diffraction pattern of the stoichiometric films confirmed the presence of three-dimensional charge order, which is consistent with the behavior of the bulk crystals as well

Isolation of a major genetic interaction associated with an extreme phenotype using assorted F2 populations in rice

Detection of quantitative trait loci (QTLs) is dependent on the materials used in the analysis, as different combinations of parental materials may lead to different outcomes in QTLs for the same trait. On the other hand, an extreme phenotype associated with a given trait implies the potential involvement of a particular allele in various allelic interactions. A genetic factor associated with such an extreme phenotype may frequently be identified from various genetic populations consisting of different parental combinations. In this study, we attempted to uncover the genetic factor associated with extremely early heading date in rice, using various F2 populations. Heading date in rice has been characterized by at least 19 QTLs, from which 12 genes have been identified. A58, a rice strain with an extremely early heading date, is adapted to Hokkaido, the northernmost limit of rice cultivation. Six F2 populations derived from crosses of A58 with six other strains displayed a range of heading dates. Genotyping using 19 QTL markers indicated that the A58 allele of the Ghd7 locus was present in most F2 individuals exhibiting extremely early heading dates. This analysis also demonstrated that when the wild-type Ehd1 allele was present, the Ghd7 allele from A58 accelerated floral induction. The results of this study demonstrate that assorted F2 populations are valuable materials for comprehensive genotyping to explore major genetic factors for extreme phenotypes, and that this methodology is broadly applicable to other unknown traits

Ferroelectricity of 20-nm Thick (Al0.8Sc0.2)N Thin Films with TiN Electrodes

identifier:oai:t2r2.star.titech.ac.jp:5067822