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Genome-wide association studies have demonstrated significant links between human brain structure and common DNA variants. Similar studies with rodents have been challenging because of smaller brain volumes. Using high field MRI (9.4 T) and compressed sensing, we have achieved microscopic resolution and sufficiently high throughput for rodent population studies. We generated whole brain structural MRI and diffusion connectomes for four diverse isogenic lines of mice (C57BL/6J, DBA/2J, CAST/EiJ, and BTBR) at spatial resolution 20,000 times higher than human connectomes. We measured narrow sense heritability (h) I.e. the fraction of variance explained by strains in a simple ANOVA model for volumes and scalar diffusion metrics, and estimates of residual technical error for 166 regions in each hemisphere and connectivity between the regions. Volumes of discrete brain regions had the highest mean heritability (0.71 ± 0.23 SD, n = 332), followed by fractional anisotropy (0.54 ± 0.26), radial diffusivity (0.34 ± 0.022), and axial diffusivity (0.28 ± 0.19). Connection profiles were statistically different in 280 of 322 nodes across all four strains. Nearly 150 of the connection profiles were statistically different between the C57BL/6J, DBA/2J, and CAST/EiJ lines. Microscopic whole brain MRI/DTI has allowed us to identify significant heritable phenotypes in brain volume, scalar DTI metrics, and quantitative connectomes.
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http://dx.doi.org/10.1016/j.neuroimage.2020.117274 | DOI Listing |
Stem Cell Rev Rep
September 2025
Department of Medical Genetics and Prenatal Diagnostics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
The emergence of organoid models has significantly bridged the gap between traditional cell cultures/animal models and authentic human disease states, particularly for genetic disorders, where their inherent genetic fidelity enables more biologically relevant research directions and enhances translational validity. This review systematically analyzes established organoid models of genetic diseases across organs (e.g.
View Article and Find Full Text PDFBreast Cancer Res Treat
September 2025
Department of Pharmacy, Duke University Hospital, Durham, NC, USA.
Purpose: Limited data is available assessing sequencing of antibody drug conjugates (ADCs) in patients with hormone receptor-positive (HR +), human epidermal growth factor 2 (HER2)-negative, HER2-low, and triple-negative metastatic breast cancer (MBC), including patients with brain metastases (BrM) or leptomeningeal disease (LMD). This study assesses the efficacy and safety of sequential sacituzumab govitecan (SG) and trastuzumab deruxtecan (T-DXd) in MBC and impact on chemotherapy (CTX).
Methods: This is a single-center, retrospective, cohort study in adult patients with HR + , HER2-negative, or low MBC who received T-DXd and/or SG.
J Assist Reprod Genet
September 2025
Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA.
Purpose: To determine if melatonin-enriched culture media could offset loss of imprinting in mouse concepti.
Methods: Zygotes were cultured to blastocyst stage under optimized conditions in melatonin-supplemented media at either 10 M (MT 10) or 10 M (MT 10), or without supplementation (Culture + embryo transfer, or ET, positive control). Blastocysts were also developed in vivo (ET negative control).
MAGMA
September 2025
Computational Imaging Group for MR Diagnostics & Therapy, Center for Image Sciences, University Medical Center Utrecht, Heidelberglaan 100, 3585CX, Utrecht, The Netherlands.
Objective: Within gradient-spoiled transient-state MR sequences like Magnetic Resonance Fingerprinting or Magnetic Resonance Spin TomogrAphy in Time-domain (MR-STAT), it is examined whether an optimized RF phase modulation can help to improve the precision of the resulting relaxometry maps.
Methods: Using a Cramer-Rao based method called BLAKJac, optimized sequences of RF pulses have been generated for two scenarios (amplitude-only modulation and amplitude + phase modulation) and for several conditions. These sequences have been tested on a phantom, a healthy human brain and a healthy human leg, to reconstruct parametric maps ( and ) as well as their standard deviations.
MAGMA
September 2025
Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
Introduction: This study explores high-impedance surface (HIS) metamaterial shields for enhancing the transmit field in whole-body MRI at 7 T. We studied the possibility of placing a metamaterial layer between the gradient coil and bore liner using electromagnetic simulations to evaluate B and SAR efficiency across different impedances.
Materials And Methods: Simulations were performed in three stages, first metamaterial design and characterization, then single-element dipole simulations with a homogenous phantom, and finally, simulations including a four-element arrays with a virtual body model, including the whole scanner geometry.