Impact of Pediatric Posterior Fossa Tumor Treatments on Working Memory Tracts Using Resting-State fMRI and Tractography.

Background And Purpose: Working memory, a primary cognitive domain, is often impaired in pediatric brain tumor survivors, affecting their attention and processing speed. This study investigated the long-term effects of treatments, including surgery, radiotherapy (RT), and chemotherapy (CT), on working memory tracts in children with posterior fossa tumors (PFTs) using resting-state functional MRI (rs-fMRI) and diffusion MRI tractography.

Methods: This study included 16 medulloblastoma (MB) survivors treated with postoperative RT and CT, 14 pilocytic astrocytoma (PA) survivors treated with surgery alone, and 16 healthy controls from the Imaging Memory after Pediatric Cancer in children, adolescents, and young adults study (NCT04324450).

An insight from the default mode network in patients with amnesia following left thalamic infarction involving the mediodorsal nucleus and mammillothalamic tract.

The role of the medial part of the thalamus, and in particular the mediodorsal nucleus (MD) and the mammillothalamic tract (MTT), in memory has long been studied, but their contribution remains unclear. While the main functional hypothesis regarding the MTT focuses on memory, some authors postulate that the MD plays a supervisory executive role (indirectly affecting memory retrieval) due to its dense structural connectivity with the prefrontal cortex (PFC). Recently, it has been proposed that the MD, MTT and PFC form part of the DMN the default mode network (DMN).

Transcription processes compete with loop extrusion to homogenize promoter and enhancer dynamics.

The spatiotemporal configuration of genes with distal regulatory elements is believed to be crucial for transcriptional control, but full mechanistic understanding is lacking. We combine simultaneous live tracking of pairs of genomic loci and nascent transcripts with molecular dynamics simulations to assess the gene and its enhancer. We find that both loci exhibit more constrained mobility than control sequences due to stalled cohesin at CCCTC-binding factor sites.

People also ask: How does this tool affect exploration-exploitation strategies with regard to prior domain knowledge and search context? An eye-tracking study.

With the diversification of Internet uses, online content type has become richer. Alongside organic results, search engine results pages now provide tools to improve information searching and learning. The People also ask (PAA) box is intended to reduce users' cognitive costs by offering easily accessible information.

Exploring Memory Systems After Pediatric Posterior Fossa Tumor: From Memory Profile Comparisons in Nonirradiated Versus Irradiated Patients to Episodic Memory Tests Capable of Detecting Radiation-induced Hippocampal Damage.

Aims: Pediatric posterior fossa tumor (PFT) survivors experience long-term cognitive sequelae, including memory disorders, for which irradiation is one of the main risk factors. The aims of the present study were to (1) explore the profile of impairment in episodic, semantic, working and procedural memory systems in irradiated versus nonirradiated PFT survivors, and (2) test whether an autobiographical questionnaire and a two-phase ecological test (Epireal) assessing episodic memory are more sensitive to radiation-induced hippocampal damage than commonly used tests.

Materials And Methods: A total of 60 participants (22 irradiated PFT survivors, 17 nonirradiated PFT survivors, and 21 controls) were included in the prospective IMPALA study.

The magnetization transfer ratio of the post-mortem canine intervertebral disk is positively correlated to Pfirrmann grading on high field 3.0T MRI: a pilot study.

Objective: Intervertebral disk (IVD) degeneration usually occurs earlier in chondrodystrophic dog breeds than in other breeds. Spinal cord compression secondary to IVD degeneration is the most common cause of myelopathy in these dogs. Standard magnetic resonance imaging (MRI) sequences permit the identification of IVD degeneration and its consequences on adjacent neurological structures.

Simple hybrid polymeric nanostructures encapsulating macro-cyclic Gd/Eu based complexes: luminescence properties and application as MRI contrast agent.

Lanthanide-based macrocycles are successfully incorporated into hybrid polyionic complexes, formed by adding a mixture of zirconium ions to a solution of a double-hydrophilic block copolymer. The resulting nanoobjects with an average radius of approximately 10-15 nm present good colloidal and chemical stability in physiological media even in the presence of competing ions such as phosphate or calcium ions. The final optical and magnetic properties of these objects benefit from both their colloidal nature and the specific properties of the complexes.

Assessment of Mendelian and risk-factor genes in Alzheimer disease: A prospective nationwide clinical utility study and recommendations for genetic screening.

Purpose: To assess the likely pathogenic/pathogenic (LP/P) variants rates in Mendelian dementia genes and the moderate-to-strong risk factors rates in patients with Alzheimer disease (AD).

Methods: We included 700 patients in a prospective study and performed exome sequencing. A panel of 28 Mendelian and 6 risk-factor genes was interpreted and returned to patients.

The long-term impact of irradiation on functional connectivity in brain circuits involved in memory processes after pediatric posterior fossa tumor.

Purpose: Memory is one of the main specific cognitive domains impaired with attention and processing speed after a pediatric brain tumor. This work explored the long-term impact of radiotherapy in children with posterior fossa tumor (PFT) on brain connectivity in neural circuits involved in memory using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods: A total of 20 irradiated and 15 non-irradiated PFT survivors, and 21 healthy controls, prospectively included in the IMPALA study (NCT04324450), performed memory tests assessing episodic, procedural, and working memories and were subjected to an rs-fMRI.

Intracranial electrical brain stimulation as an approach to studying the (dis)continuum of memory experiential phenomena.

Déjà vu and involuntary autobiographical memories (IAM) can be induced by intracranial electric brain stimulation in epileptic patients, sometimes in the same individual. We suggest that there may be different types of IAM which should be taken into account and provide several ideas to test the hypothesis of a continuity between IAM and déjà vu phenomena.

Diffusion tensor imaging tractography in the one-humped camel () brain.

Introduction: Tractography is a technique used to trace the pathways of the brain using noninvasive diffusion tensor imaging (DTI) data. It is becoming increasingly popular for investigating the brains of domestic mammals and other animals with myelinated fibers but the principle of DTI can also apply for those with unmyelinated fibers. In the case of camels, DTI tractography is a promising method for enhancing current knowledge of the brain's structural connectivity and identifying white-matter tract changes potentially linked to neurodegenerative pathologies.

Country of birth is associated with discrepancies in the prescription of two-drug regimens in successfully treated people with HIV in France.

Objectives: We aimed to examine the association of the country of birth and the other patients' characteristics with the prescription of two-drug regimens (2DRs) in virally suppressed people with HIV (PWH) in France.

Design: Observational study conducted from the national Dat'AIDS prospectively collected database.

Methods: We included all adults who were actively in care on 31 December 2020 in 26 French centers, with an HIV plasma viral load (pVL) <50 copies/ml for at least 6 months while on antiretroviral therapy (ART).

Huntington's Disease with Small CAG Repeat Expansions.

Background: Carriers of small cytosine-adenine-guanine (CAG) repeats below 39 in the HTT gene are traditionally associated with milder Huntington's disease, but their clinical profile has not been extensively studied.

Objective: To study the phenotype of CAG repeat carriers.

Methods: We included 35 patients and premanifest carriers of CAG repeats.

Amygdala hyperactivation relates to eating behaviour: a potential indicator of food addiction in Prader-Willi syndrome.

Prader-Willi syndrome is a rare neurodevelopmental genetic disorder characterized by various endocrine, cognitive and behavioural problems. The symptoms include an obsession for food and reduced satiety, which leads to hyperphagia and morbid obesity. Neuropsychological studies have reported that Prader-Willi patients display altered social interactions with a specific weakness in interpreting social information and responding to them, a symptom close to that observed in autism spectrum disorders.

Competition between transcription and loop extrusion modulates promoter and enhancer dynamics.

The spatiotemporal configuration of genes with distal regulatory elements, and the impact of chromatin mobility on transcription, remain unclear. Loop extrusion is an attractive model for bringing genetic elements together, but how this functionally interacts with transcription is also largely unknown. We combine live tracking of genomic loci and nascent transcripts with molecular dynamics simulations to assess the 4D arrangement of the gene and its enhancer, in response to a battery of perturbations.

Country of birth is associated with antiretroviral therapy choice in treatment-naive persons with HIV in France.

Objectives: We aimed to describe factors associated with the choice of first antiretroviral therapy (ART) in persons with HIV (PWH) in France, included the country of birth, as well as the time to undetectable viral load and treatment discontinuation.

Design: Observational study conducted from the national Dat'AIDS prospectively collected database.

Methods: We included all adults who started their first ART between 01 January 2014 and 31 December 2020, with a pretherapeutic plasma viral load (pVL) at least 400 copies/ml.

Impact of a pediatric posterior fossa tumor and its treatments on motor procedural learning.

Introduction: Posterior fossa tumor (PFT) survivors have difficulty learning new skills. Procedural memory is a skill learning system that allows, through training, the automatization of procedures and progressive improvement of performance. It underlies most of the motor procedures in everyday life that we perform automatically, such as riding a bike or writing.

Should an elective contralateral neck dissection be performed in midline-reaching squamous cell carcinomas of the oral cavity and oropharynx?

Objective: to compare the rate of occult contralateral neck metastases (OCNM) in oral and oropharyngeal squamous cell carcinomas (SCC) reaching or crossing the midline and to identify risk factors for OCNM.

Materials And Methods: we conducted a single-center retrospective study of oral and oropharyngeal SCC with contralateral cN0 neck. The cohort was divided into a midline-reaching (MR; approaching the midline from up to 10 mm) group and a midline-crossing (MC; exceeding the midline by up to 10 mm) group.

Specific profiles of new-onset vs. non-inaugural status epilepticus: From diagnosis to 1-year outcome.

While new-onset status epilepticus (NOSE) is a harbinger of chronic epilepsy, prospective medical data are sparse in terms of specifying whether the evolution of status epilepticus (SE) and seizure expression in NOSE resembles what occurs in patients who have already been diagnosed with epilepsy [non-inaugural SE (NISE)] in all aspects apart from its inaugural nature. The aim of this study was to compare the clinical, MRI, and EEG features that could distinguish NOSE from NISE. We conducted a prospective monocentric study in which all patients ≥18 years admitted for SE over a 6-month period were included.

Determining Prior Authorization Approval for Lumbar Stenosis Surgery With Machine Learning.

Study Design: Medical vignettes.

Objectives: Lumbar spinal stenosis (LSS) is a degenerative condition with a high prevalence in the elderly population, that is associated with a significant economic burden and often requires spinal surgery. Prior authorization of surgical candidates is required before patients can be covered by a health plan and must be approved by medical directors (MDs), which is often subjective and clinician specific.

Assemblies of poly(-vinyl-2-pyrrolidone)-based double hydrophilic block copolymers triggered by lanthanide ions: characterization and evaluation of their properties as MRI contrast agents.

Because of the formation of specific antibodies to poly(ethylene glycol) (PEG) leading to life-threatening side effects, there is an increasing need to develop alternatives to treatments and diagnostic methods based on PEGylated copolymers. Block copolymers comprising a poly(-vinyl-2-pyrrolidone) (PVP) segment can be used for the design of such vectors without any PEG block. As an example, a poly(acrylic acid)--poly(-vinyl-2-pyrrolidone) (PAA--PVP) copolymer with controlled composition and molar mass is synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization.

Pseudoprogression in GBM versus true progression in patients with glioblastoma: A multiapproach analysis.

Background And Purpose: To investigate the feasibility of using a multiapproach analysis combining clinical data, diffusion- and perfusion-weighted imaging, and 3D magnetic resonance spectroscopic imaging to distinguish true tumor progression (TP) from pseudoprogression (PSP) in patients with glioblastoma.

Materials And Methods: Progression was suspected within 6 months of radiotherapy in 46 of the 180 patients included in the Phase-III SpectroGlio trial (NCT01507506). Choline/creatine (Cho/Cr), choline/N-acetyl aspartate (Cho/NAA) and lactate/N-acetyl aspartate (Lac/NAA) ratios were extracted.