MICCAI-CDMRI 2023 QuantConn Challenge Findings on Achieving Robust Quantitative Connectivity through Harmonized Preprocessing of Diffusion MRI.

White matter alterations are increasingly implicated in neurological diseases and their progression. International-scale studies use diffusion-weighted magnetic resonance imaging (DW-MRI) to qualitatively identify changes in white matter microstructure and connectivity. Yet, quantitative analysis of DW-MRI data is hindered by inconsistencies stemming from varying acquisition protocols.

Sample size estimates for biomarker-based outcome measures in clinical trials in autosomal dominant Alzheimer's disease.

Introduction: Alzheimer disease (AD)-modifying therapies are approved for treatment of early-symptomatic AD. Autosomal dominant AD (ADAD) provides a unique opportunity to test therapies in presymptomatic individuals.

Methods: Using data from the Dominantly Inherited Alzheimer Network (DIAN), sample sizes for clinical trials were estimated for various cognitive, imaging, and CSF outcomes.

Association Between Sleep Position, Obesity, and Obstructive Sleep Apnea Severity.

Background: This study examines the relationship between obstructive sleep apnea severity, sleep position, and body weight, particularly focusing on the negative impact of sleeping in a supine position combined with being overweight in a population-based sample.

Methods: The Apnea-Hypopnea Index (AHI) was utilized as a marker of OSA severity and sleep position from a standardized overnight polysomnography. Participants were categorized by body mass index (BMI) (kg/m) into normal weight/underweight (<25) and overweight (≥25).

Upregulated miR-10b-5p as a potential miRNA signature in amyotrophic lateral sclerosis patients.

Amyotrophic lateral sclerosis (ALS) is a fatal, adult-onset disease marked by a progressive degeneration of motor neurons (MNs) present in the spinal cord, brain stem and motor cortex. Death in most patients usually occurs within 2-4 years after symptoms onset. Despite promising progress in delineating underlying mechanisms, such as disturbed proteostasis, DNA/RNA metabolism, splicing or proper nucleocytoplasmic shuttling, there are no effective therapies for the vast majority of cases.

Identification of a Therapeutic Window for Neurovascular Unit Repair after Experimental Spinal Cord Injury.

Traumatic spinal cord injury (SCI) is a devastating condition for which effective neuroregenerative and neuroreparative strategies are lacking. The post-traumatic disruption of the blood-spinal cord barrier (BSCB) as part of the neurovascular unit (NVU) is one major factor in the complex pathophysiology of SCI, which is associated with edema, inflammation, and cell death in the penumbra regions of the spinal cord adjacent to the lesion epicenter. Thus, the preservation of an intact NVU and vascular integrity to facilitate the regenerative capacity following SCI is a desirable therapeutic target.

Documentation of prodromal features and risk factors of dementia disease in primary care practice.

Background: Documented risk factors and prodromal features of dementia in primary care practices may support dementia prevention and early detection in routine care.

Objective: To identify documented prodromal features and risk factors of dementia before the incident dementia diagnosis in German primary care practices.

Methods: This case-control study used documented diagnoses (risk factors, prodromal features) and prescriptions of primary care practices for 73,717 patients with dementia disease and 73,717 matched controls (ratio 1:1).

Aβ status assessment in a hypothetical scenario prior to treatment with disease-modifying therapies: Evidence from 10-year real-world experience at university memory clinics.

Introduction: With the advent of disease-modifying therapies, accurate assessment of biomarkers indicating the presence of disease-associated amyloid beta (Aβ) pathology becomes crucial in patients with clinically suspected Alzheimer's disease (AD). We evaluated Aβ levels in cerebrospinal fluid (Aβ CSF) and Aβ levels in positron emission tomography (Aβ PET) biomarkers in a real-world memory-clinic setting to develop an efficient algorithm for clinical use.

Methods: Patients were evaluated for AD-related Aβ pathology from two independent cohorts (Ludwig Maximilian University [LMU],  = 402, and Medical University of Vienna [MUV],  = 144).

Understanding brain cancer and exploiting its vulnerabilities.

Brain cancer is one of the most devastating neoplasms affecting both children and adults. Its dismal prognosis has for long-time discouraged research in this area. However, in the last 10-15 years remarkable progress has been made in our understanding of brain cancer biology, thus showing promise for the identification of new ways to treat these tumors towards the improvement of patients' survival and quality of life.

Neuronal and oligodendroglial, but not astroglial, tau translates to in vivo tau PET signals in individuals with primary tauopathies.

Tau PET has attracted increasing interest as an imaging biomarker for 4-repeat (4R)-tauopathy progressive supranuclear palsy (PSP). However, the translation of in vitro 4R-tau binding to in vivo tau PET signals is still unclear. Therefore, we performed a translational study using a broad spectrum of advanced methodologies to investigate the sources of [F]PI-2620 tau PET signals in individuals with 4R-tauopathies, including a pilot PET autopsy study in patients.

Constitutive HIF-1α Expression in the Epidermis Fuels Proliferation and Is Essential for Effective Barrier Formation.

Epidermis is one of the most rapidly proliferating tissues in the body with high demands for adenosine triphosphate and cellular building blocks. In this study, we show that to meet these requirements, keratinocytes constitutively express HIF-1α, even in the presence of oxygen levels sufficient for HIF-1α hydroxylation. We previously reported that mice with severe epidermal mitochondrial dysfunction actually showed a hyperproliferative epidermis but rapidly died of systemic lactic acidosis and hypoglycemia, indicating excessive glycolysis.

A tailored intervention for the detection of patients with coronary heart disease and mental or cognitive comorbidities in the German primary care setting: qualitative evaluation of implementation success.

Background: Guidelines recommend the identification of potential mental and/or cognitive disorders (MCD) in patients with coronary heart disease (CHD). However, compliance with these guidelines appears to be lacking in primary care. A minimal invasive intervention was tailored with experts for the primary care setting to increase the identification of this patient group and ensure proper treatment.

VINNA for neonates: Orientation independence through latent augmentations.

A robust, fast, and accurate segmentation of neonatal brain images is highly desired to better understand and detect changes during development and disease, specifically considering the rise in imaging studies for this cohort. Yet, the limited availability of ground truth datasets, lack of standardized acquisition protocols, and wide variations of head positioning in the scanner pose challenges for method development. A few automated image analysis pipelines exist for newborn brain Magnetic Resonance Image (MRI) segmentation, but they often rely on time-consuming non-linear spatial registration procedures and require resampling to a common resolution, subject to loss of information due to interpolation and down-sampling.

Geometric deep learning for diffusion MRI signal reconstruction with continuous samplings (DISCUS).

Diffusion-weighted magnetic resonance imaging (dMRI) permits a detailed in-vivo analysis of neuroanatomical microstructure, invaluable for clinical and population studies. However, many measurements with different diffusion-encoding directions and possibly -values are necessary to infer the underlying tissue microstructure within different imaging voxels accurately. Two challenges particularly limit the utility of dMRI: limit feasible scans to only a few directional measurements, and the makes it difficult to combine datasets.

FastSurfer-HypVINN: Automated sub-segmentation of the hypothalamus and adjacent structures on high-resolutional brain MRI.

The hypothalamus plays a crucial role in the regulation of a broad range of physiological, behavioral, and cognitive functions. However, despite its importance, only a few small-scale neuroimaging studies have investigated its substructures, likely due to the lack of fully automated segmentation tools to address scalability and reproducibility issues of manual segmentation. While the only previous attempt to automatically sub-segment the hypothalamus with a neural network showed promise for 1.

Transcriptomic mapping of the 5-HT receptor landscape.

Serotonin (5-HT) is crucial for regulating brain functions such as mood, sleep, and cognition. This study presents a comprehensive transcriptomic analysis of 5-HT receptors (Htrs) across ≈4 million cells in the adult mouse brain using single-cell RNA sequencing (scRNA-seq) data from the Allen Institute. We observed differential transcription patterns of all 14 Htr subtypes, revealing diverse prevalence and distribution across cell classes.

Proton-free induction decay MRSI at 7 T in the human brain using an egg-shaped modified rosette K-space trajectory.

Purpose: Proton (H)-MRSI via spatial-spectral encoding poses high demands on gradient hardware at ultra-high fields and high-resolutions. Rosette trajectories help alleviate these problems, but at reduced SNR-efficiency because of their k-space densities not matching any desired k-space filter. We propose modified rosette trajectories, which more closely match a Hamming filter, and thereby improve SNR performance while still staying within gradient hardware limitations and without prolonging scan time.

GenoTools: an open-source Python package for efficient genotype data quality control and analysis.

GenoTools, a Python package, streamlines population genetics research by integrating ancestry estimation, quality control, and genome-wide association studies capabilities into efficient pipelines. By tracking samples, variants, and quality-specific measures throughout fully customizable pipelines, users can easily manage genetics data for large and small studies. GenoTools' "Ancestry" module renders highly accurate predictions, allowing for high-quality ancestry-specific studies, and enables custom ancestry model training and serialization specified to the user's genotyping or sequencing platform.