Acceleration and transport of ions in turbulent current sheets: formation of non-maxwelian energy distribution

The paper is devoted to particle acceleration in turbulent current sheet (CS). Our results show that the mechanism of CS particle interaction with electromagnetic turbulence can explain the formation of power law energy distributions. We study the ratio between adiabatic acceleration of particles in electric field in the presence of stationary turbulence and acceleration due to electric field in the case of dynamic turbulence. The correlation between average energy gained by particles and average particle residence time in the vicinity of the neutral sheet is discussed. It is also demonstrated that particle velocity distributions formed by particle-turbulence interaction are similar in essence to the ones observed near the far reconnection region in the Earth's magnetotail

Variability of Cerebral Deep Venous System in Preterm and Term Neonates Evaluated on MR SWI Venography

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Early Pain Exposure Influences Functional Brain Connectivity in Very Preterm Neonates

Background: Early exposure to nociceptive events may cause brain structural alterations in preterm neonates, with long-lasting consequences on neurodevelopmental outcome. Little is known on the extent to which early pain may affect brain connectivity. We aim to evaluate brain functional connectivity changes in preterm neonate that underwent multiple invasive procedures during the postnatal period, and to correlate them with the neurodevelopmental outcome at 24 months. Methods: In this prospective case-control study, we collected information about exposure to painful events during the early postnatal period and resting-state BOLD-fMRI data at term equivalent age from two groups of preterm neonate: 33 subjected to painful procedures during the neonatal intensive care (mean gestational age 27.9 \ub1 1.8 weeks) and 13 who did not require invasive procedures (average gestational age 31.2 \ub1 2.1 weeks). A data-driven principal-component-based multivariate pattern analysis (MVPA) was used to investigate the effect of early pain exposure on brain functional connectivity, and the relationship between connectivity changes and neurodevelopmental outcome at 24 months, assessed with Griffiths, Developmental Scale-Revised: 0\u20132. Results: Early pain was associated with decreased functional connectivity between thalami and bilateral somatosensory cortex, and between the right insular cortex and ipsilateral amygdala and hippocampal regions, with a more evident effect in preterm neonate undergoing more invasive procedures. Functional connectivity of the right thalamocortical pathway was related to neuromotor outcome at 24 months (P = 0.003). Conclusion: Early exposure to pain is associated with abnormal functional connectivity of developing networks involved in the modulation of noxious stimuli in preterm neonate, contributing to the neurodevelopmental consequence of preterm birth

Integrative Neuropsychological Characteristics of Subcortical-Frontal Brain Regions as a Schizophrenia Liability Factor

Para estudiar las características de las regiones cerebrales subcórtico-frontal, se investigaron la función y la evaluación de su relación con la vulnerabilidad a la esquizofrenia en 59 pacientes y 23 controles, empleando los métodos neuropsicológicos de Luria. El análisis estableció anormalidades bilaterales de la función de las zonas lobulares prefrontal y frontal profunda en pacientes comparados con los controles. Estas anormalidades eran más predominantes en el hemisferio izquierdo. Las coeficientes de correlación punto-biserial de algunos indicadores neuropsicológicos integrativos con la vulnerabilidad a la esquizofrenia eran de 0,39 ± 0,11 y 0,28 ± 0,09, respectivamente. Los datos obtenidos llevan a la discusión de los indicadores neuropsicológicos integrativos de regiones subcortical-frontales del cerebro que se revelan como marcadores potenciales de vulnerabilidad a la esquizofrenia y confirma el papel de la asimetría estructural y funcional del cerebro en la patogénesis de la esquizofrenia.In order to study neuropsychological characteristics of subcortical-frontal brain regions function and assessment of their relation with vulnerability to schizophrenia 59 patients and 23 controls were investigated using Luria’s neuropsychological methods. The analysis established bilateral abnormalities of the function of prefrontal and profound frontal lobe zones in patients as compared with controls. These abnormalities were more predominate in the left hemisphere. Point biserial correlation coefficients of determined integrative neuropsychological indicators with liability to schizophrenia were 0.39 ± 0.11 and 0.28 ± 0.09, for the left and right brain zones respectively. The obtained data permits discussion of the integrative neuropsychological indicators of subcorticalfrontal brain regions as potential markers of liability to schizophrenia and confirms the role of structural and functional brain asymmetry in the pathogenesis of schizophrenia

Randomized Control Trial of Postnatal rhIGF-1/rhIGFBP-3 Replacement in Preterm Infants: Post-hoc Analysis of Its Effect on Brain Injury

Background: Postnatal insulin-like growth factor-1 (IGF-1) replacement with recombinant human (rh)IGF-1 and IGF binding protein-3 (rhIGF-1/rhIGFBP-3) is being studied as a potential treatment to reduce comorbidities of prematurity. We have recently reported on a phase II, multicenter, randomized, controlled trial comparing postnatal rhIGF-1/rhIGFBP-3 replacement with standard of care (SOC) in extremely preterm infants (NCT01096784). Maximum severity of retinopathy of prematurity was the primary endpoint of the trial and presence of GMH-IVH/PHI one of the pre-specified secondary endpoints. Infants therefore received serial cranial ultrasound scans (CUS) between birth and term age. In this post-hoc analysis we present a detailed analysis of the CUS data of this trial and evaluate the effect of postnatal rhIGF-1/rhIGFBP-3 replacement on the incidence of different kinds of brain injury in extremely preterm infants. Methods: This report is an exploratory post-hoc analysis of a phase II trial in which infants <28 weeks gestational age were randomly allocated to rhIGF-1/rhIGFBP-3 or SOC. Serial cranial ultrasounds were performed between birth and term-equivalent age. Presence of germinal matrix hemorrhage and intraventricular hemorrhage (GMH-IVH), periventricular hemorrhagic infarction (PHI), post-hemorrhagic ventricular dilatation, and white matter injury (WMI) were scored by two independent masked readers. Results: The analysis included 117 infants; 58 received rhIGF-1/rhIGFBP-3 and 59 received SOC. A trend toward less grade II–III GMH-IVH and PHI was observed in treated infants vs. SOC. A subanalysis of infants without evidence of GMH-IVH at study entry (n = 104) showed reduced progression to GMH-IVH in treated infants (25.0% [13/52] vs. 40.4% [21/52]; not significant). No effects of rhIGF-1/rhIGFBP-3 on WMI were observed. Conclusion: The potential protective effect of rhIGF-1/rhIGFBP-3 on the occurrence of GMH-IVH/PHI appeared most pronounced in infants with no evidence of GMH-IVH at treatment start

Neonatal developmental venous anomalies: Clinicoradiologic characterization and follow-up

BACKGROUND AND PURPOSE: Although developmental venous anomalies have been frequently studied in adults and occasionally in children, data regarding these entities are scarce in neonates. We aimed to characterize clinical and neuroimaging features of neonatal developmental venous anomalies and to evaluate any association between MR imaging abnormalities in their drainage territory and corresponding angioarchitectural features. MATERIALS AND METHODS: We reviewed parenchymal abnormalities and angioarchitectural features of 41 neonates with developmental venous anomalies (20 males; mean corrected age, 39.9 weeks) selected through a radiology report text search from 2135 neonates who underwent brain MR imaging between 2008 and 2019. Fetal and longitudinal MR images were also reviewed. Neurologic outcomes were collected. Statistics were performed using x 2, Fisher exact, Mann-Whitney U, or t tests corrected for multiple comparisons. RESULTS: Developmental venous anomalies were detected in 1.9% of neonatal scans. These were complicated by parenchymal/ventricular abnormalities in 15/41 cases (36.6%), improving at last follow-up in 8/10 (80%), with normal neurologic outcome in 9/14 (64.2%). Multiple collectors (P =.008) and larger collector caliber (P <.001) were significantly more frequent in complicated developmental venous anomalies. At a patient level, multiplicity (P =.002) was significantly associated with the presence of ≥1 complicated developmental venous anomaly. Retrospective fetal detection was possible in 3/11 subjects (27.2%). CONCLUSIONS: One-third of neonatal developmental venous anomalies may be complicated by parenchymal abnormalities, especially with multiple and larger collectors. Neuroimaging and neurologic outcomes were favorable in most cases, suggesting a benign, self-limited nature of these vascular anomalies. A congenital origin could be confirmed in one-quarter of cases with available fetal MR imaging