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Noninvasive extracellular pH (pHe) mapping with Biosensor Imaging of Redundant Deviation in Shifts (BIRDS) using MR spectroscopic imaging (MRSI) has been demonstrated on 3T clinical MR scanners at 8 ×8×10 mm3 spatial resolution and applied to study various liver cancer treatments. Although pHe imaging at higher resolution can be achieved by extending the acquisition time, a postprocessing method to increase the resolution is preferable, to minimize the duration spent by the subject in the MR scanner. In this work, we propose to improve the spatial resolution of pHe mapping with BIRDS by incorporating anatomical information in the form of multiparametric MRI and using an unsupervised deep‐learning technique, Deep Image Prior (DIP). Specifically, we used high‐resolution T1, T2, and diffusion‐weighted imaging (DWI) MR images of rabbits with VX2 liver tumors as inputs to a U‐Net architecture to provide anatomical information. U‐Net parameters were optimized to minimize the difference between the output super‐resolution image and the experimentally acquired low‐resolution pHe image using the mean‐absolute error. In this way, the super‐resolution pHe image would be consistent with both anatomical MR images and the low‐resolution pHe measurement from the scanner. The method was developed based on data from 49 rabbits implanted with VX2 liver tumors. For evaluation, we also acquired high‐resolution pHe images from two rabbits, which were used as ground truth. The results indicate a good match between the spatial characteristics of the super‐resolution images and the high‐resolution ground truth, supported by the low pixelwise absolute error. [ABSTRACT FROM AUTHOR]

Objective: To characterize DNA methylation (DNAm) differences between sporadic Parkinson's disease (PD) and healthy control (HC) individuals enrolled in the Parkinson's Progression Markers Initiative (PPMI). Methods: Using whole blood, we characterized longitudinal differences in DNAm between sporadic PD patients (n = 196) and HCs (n = 86) enrolled in PPMI. RNA sequencing (RNAseq) was used to conduct gene expression analyses for genes mapped to differentially methylated cytosine‐guanine sites (CpGs). Results: At the time of patient enrollment, 5,178 CpGs were differentially methylated (2,683 hypermethylated and 2,495 hypomethylated) in PD compared to HC. Of these, 579 CpGs underwent significant methylation changes over 3 years. Several differentially methylated CpGs were found near the cytochrome P450 family 2 subfamily E member 1 (CYP2E1) gene. Additionally, multiple hypermethylated CpGs were associated with the N‐myc downregulated gene family member 4 (NDRG4) gene. RNA‐Seq analyses showed 75 differentially expressed genes in PD patients compared to controls. An integrative analysis of both differentially methylated sites and differentially expressed genes revealed 20 genes that exhibited hypomethylation concomitant with overexpression. Additionally, 1 gene, cathepsin H (CTSH), displayed hypermethylation that was associated with its decreased expression. Interpretation: We provide initial evidence of alterations in DNAm in blood of PD patients that may serve as potential epigenetic biomarker of disease. To evaluate the significance of these changes throughout the progression of PD, additional profiling at longer intervals and during the prodromal stages of disease will be necessary. ANN NEUROL 2024;95:1162–1172 [ABSTRACT FROM AUTHOR]

Maize ear rot, one of the most destructive diseases in summer‐sown maize areas of China, is caused by several Fusarium spp. Not only does this pathogen lower maize yields, but also negatively impacts both animal and human health through the production of fumonisin mycotoxins. In this study, we collected 472 unique isolates of F. verticillioides from 480 samples of maize ear rots across eight Chinese summer‐sown maize regions and evaluated their genetic variability and aggressiveness. Analysis of polymorphic intersimple sequence repeat (ISSR) loci revealed high levels of genetic variation, particularly in Henan and Shandong provinces. The STRUCTURE result showed that all F. verticillioides isolates clustered into three populations, rather than eight distinct geographical provinces, and there was no significant positive correlation between genetic distance and geographical distance. Most of the variation resulted from genetic differences within rather than between populations. Pathogenicity varied among the evaluated F. verticillioides isolates, and most isolates examined, caused a moderate level of disease; there was no strong correlation between pathogenicity and genetic diversity. This is the first comprehensive report of both the genetic variability and pathogenicity of F. verticillioides across the whole summer‐sown maize region in China. These results provide important information that can inform efforts to control maize ear rot and fumonisin contamination caused by F. verticillioides. [ABSTRACT FROM AUTHOR]

Background and purpose: We used two‐sample Mendelian randomization (MR) to examine the effects of blood lipids and lipid‐modifying drugs on intracranial aneurysm (IA). Methods: Genetic variants for the effects of high‐density lipoprotein cholesterol (HDL‐C), apolipoprotein A1, low‐density lipoprotein cholesterol (LDL‐C), apolipoprotein B, and triglycerides and targets for lipid‐modifying drugs were selected from the genome‐wide discovery analyses of the UK Biobank. Summary‐level data on IAs were obtained from the International Stroke Genetics Consortium. Univariate and multivariate MR analyses were performed. Results: Univariate MR analyses showed that the HDL‐C was negatively correlated with IA (odds ratio [OR] = 0.816, 95% confidence interval [CI] = 0.715–0.932, p = 0.003) and ruptured IA (rIA; OR = 0.775, 95% CI = 0.663–0.906, p = 0.001). The multivariate MR–inverse variance weighted analysis showed that the HDL‐C was negatively correlated with IA (OR = 0.655, 95% CI = 0.434–0.988, p = 0.043) and rIA (OR = 0.563, 95% CI = 0.347–0.913, p = 0.02), and the LDL‐C was negatively correlated with IA (OR = 0.402, 95% CI = 0.191–0.848, p = 0.017) and rIA (OR = 0.376, 95% CI = 0.160–0.883, p = 0.025). Using genetic proxies of known lipid‐modifying drugs, we found that the increased HDL‐C with cholesterol ester transfer protein proxies was associated with a decreased risk of rIA (OR = 0.852, 95% CI = 0.747–0.973, p = 0.018), and the decreased LDL‐C with 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase proxies was associated with increased risk of IA (OR = 1.772, 95% CI = 1.080–2.908, p = 0.024) and rIA (OR = 1.856, 95% CI = 1.022–3.371, p = 0.042). Conclusions: Genetically determined HDL‐C and LDL‐C reduce the risk of IA and rIA. The effects of different lipid‐modifying drugs on IA need to be further investigated. [ABSTRACT FROM AUTHOR]

Inorganic–organic hybrid films containing two‐dimensional nanosheets have shown good gas barrier performance, but moderate tensile property, because of the rigid characteristics of covalent or ionic bonds between the assembly units. In this work, we used LDH nanosheets rich in hydroxyl groups as building units, followed by modification of tannic acid (TA), to assemble with polyethylene oxide (PEO) through hydrogen bonds. Compared with previous work, the tensile property and oxygen barrier performance of (TA@LDH/PEO)n films have been significantly improved. A 50‐bilayer TA@LDH/PEO film, deposited on a 1 mm thick natural rubber substrate, results in a 29× reduction (contrast with bare substrate) in oxygen transmission rate and maintains its good barrier property even under a large elongation of 120%. The excellent tensile and gas barrier properties are attributed to the ductility of hydrogen bond network among building blocks and the significant prolongation of oxygen transmission path induced by LDH nanosheets. [ABSTRACT FROM AUTHOR]

Background and Aim: Esophageal carcinoma has been regarded as one of the top 10 common malignancies globally. Esophageal squamous cell carcinoma (ESCC) is an important subtype of esophageal carcinoma with approximately 20% survival rate. Long noncoding RNAs were documented to regulate the occurrence or progression of several tumors. However, neither the biological role nor the molecular mechanism of LINC00467 has been explored. This research is aimed to investigating the regulatory mechanism of LINC00467 in ESCC. Methods: In this study, a series of experiments including reverse transcription–quantitative polymerase chain reaction, Cell Counting Kit‐8, luciferase reporter, western blot, and RNA immunoprecipitation were designed and conducted to explore the potential function and mechanism of LINC00467 in ESCC. Results: According to experimental results, we found out upregulated LINC00467 improved cell proliferation, but hindered cell apoptosis. In mechanism, miR‐485‐5p was predicted, screened out, and validated to combine with LINC00467, which displayed lower expression in ESCC. Additionally, miR‐485‐5p negatively regulated and directly targeted DPAGT1. Rescue assays suggested that DPAGT1 amplification was able to recover the influence of LINC00467 deficiency on cell proliferation and apoptosis. Furthermore, knockdown of LINC00467 suppressed tumor growth in vivo. Conclusion: We proved that LINC00467 acted as an oncogene in ESCC by accelerating cell proliferation and preventing cell apoptosis via miR‐485‐5p/DPAGT1 axis. This may provide a potential diagnostic marker for ESCC treatment. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a poly(ϵ‐caprolactone)/poly(ether‐b‐amide) blend with weight ratio 35/65 was prepared by solution mixing and compression molding. A simple and sensible method to control the phase separation structure was introduced by adjusting the temperature and time for the process of phase separation. Samples with obviously different morphology were obtained and the microstructure was studied by phase contrast optical microscopy, SEM and DSC. The shape memory properties were measured using dynamic mechanical analysis. The results show that the shape memory performance of the blend is closely related to the phase morphology, and the blend with co‐continuous structure has a better shape memory property. A model is put forward to illustrate schematically the microstructural evolution during the shape memory process. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Bi2((Mg1/3Nb2/3)1-xTix)2O7 ceramics with 0 ≤ x ≤ 0.4 were synthesized using solid-state reaction method and could be sintered densely at low temperature under 950 °C. The crystal structure is pure cubic pyrochlore for the compositions with 0 ≤ x ≤ 0.3. When x > 0.3, it transforms from orthorhombic weberite into cubic pyrochlore with the increase in sintering temperature. Permittivity of cubic pyrochlore Bi2((Mg1/3Nb2/3)1-xTix)2O7 ceramics with 0 ≤ x ≤ 0.2 is ~160. In addition, the ceramics have very low dielectric loss (<4 × 10−4) and tunable temperature coefficient of capacitance from −300 to −500 ppm/°C with the increase in Ti content. These merits make the compositions be potential candidates for multilayer ceramic capacitors and low-temperature co-fired ceramics. [ABSTRACT FROM AUTHOR]