34 research outputs found
Histologic chorioamnionitis and risk of neurodevelopmental impairment at age 10 years among extremely preterm infants born before 28 weeks of gestation
Background: Extremely preterm infants whose placenta had histologic evidence of chorioamnionitis have early brain dysfunction, but little is known about neurologic development at 10 years of age. Objective: We investigated the association between histologic chorioamnionitis and neurodevelopmental impairment at 10 years among children born 2 standard deviations below the mean), and epilepsy at the age of 10 years by blinded evaluators using validated measures. Multivariable logistic regression with generalized estimating equations was used. Results: Among 805 placentas, 43% (347/805) had histologic chorioamnionitis by moderate or advanced maternal stage, 36% (286/805) by severe maternal grade, 18% (132/737) by moderate or advanced fetal stage, and 1% (10/737) by severe fetal grade. The frequencies of impairments were 11% (88/767) for cerebral palsy, 7% (56/773) for autism spectrum disorder, 15% (120/788) for cognitive impairment, and 7% (52/763) for epilepsy. After adjustment for maternal age, body mass index, race, insurance status, maternal education, tobacco use, infant sex, and multiple gestations, the adjusted odds ratio for the association between histologic chorioamnionitis and cerebral palsy years was increased with advanced maternal stage (adjusted odds ratio, 2.5; 95% confidence interval, 1.6â3.9), severe maternal grade (adjusted odds ratio, 2.0; 95% confidence interval, 1.2â3.4), moderate fetal stage (adjusted odds ratio, 2.20; 95% confidence interval, 2.1â2.2), and mild or moderate fetal grade (adjusted odds ratio, 1.5; 95% confidence interval, 1.0â2.2). Similarly, the adjusted odds ratio for the association between histologic chorioamnionitis and epilepsy was increased with advanced maternal stage (adjusted odds ratio, 1.5; 95% confidence interval, 1.3â1.6) and severe fetal grade (adjusted odds ratio, 5.9; 95% confidence interval, 1.9â17.8). In addition, the adjusted odds ratio for the association between histologic chorioamnionitis and autism spectrum disorder was increased with mild or moderate fetal grade (adjusted odds ratio, 1.7; 95% confidence interval, 1.0â2.9). Histologic chorioamnionitis was not associated with cognitive impairment. These findings held after adjustment for gestational age at delivery. In contrast to histologic chorioamnionitis, a clinical diagnosis of chorioamnionitis was not associated with neurodevelopmental impairment. Conclusion: Histologic chorioamnionitis may be associated with some forms of neurodevelopmental impairment at 10 years of life among infants born <28 weeksâ gestation
Particles-vortex interactions and flow visualization in He4
Recent experiments have demonstrated a remarkable progress in implementing
and use of the Particle Image Velocimetry (PIV) and particle tracking
techniques for the study of turbulence in He4. However, an interpretation of
the experimental data in the superfluid phase requires understanding how the
motion of tracer particles is affected by the two components, the viscous
normal fluid and the inviscid superfluid. Of a particular importance is the
problem of particle interactions with quantized vortex lines which may not only
strongly affect the particle motion, but, under certain conditions, may even
trap particles on quantized vortex cores. The article reviews recent
theoretical, numerical, and experimental results in this rapidly developing
area of research, putting critically together recent results, and solving
apparent inconsistencies. Also discussed is a closely related technique of
detection of quantized vortices negative ion bubbles in He4.Comment: To appear in the J Low Temperature Physic
Toward Accelerated Authorization and Access to New Medicines for Juvenile Idiopathic Arthritis
A meeting was organized to bring together multiple stakeholders involved in the testing and authorization of new medications for juvenile idiopathic arthritis (JIA) to discuss current issues surrounding clinical trials and access to new medications for children and adolescents with JIA. The Childhood Arthritis and Rheumatology Research Alliance invited representatives of regulatory agencies (Food and Drug Administration and European Medicines Agency), and major pharmaceutical companies with JIAâapproved products or products in development, patient and parent representatives, representatives of an advocacy organization (Arthritis Foundation), and pediatric rheumatology clinicians/investigators to a 1âday meeting in April 2018. The participants engaged in discussion regarding issues in clinical trials. As the pharmacologic options to treat inflammatory arthritis rapidly expand, registration trial designs to test medications in JIA patients must adapt. Many methodologies successfully used in the recent past are no longer feasible. The pool of patients meeting entry criteria who are willing to participate is shrinking while the number of medications to be tested is growing. Suggested solutions included proposing innovative clinical trial methods to regulatory agencies, as well as open discussions among stakeholders. Ensuring that new medications are authorized in a timely manner to meet the needs of JIA patients worldwide is critical. Approaches should include open dialog between regulatory agencies, pharmaceutical companies, and other stakeholders to develop and implement novel study designs, including patient and clinician perspectives to define meaningful trial outcomes, and changing existing study plans
One-Dimensional Stacking of Bifunctional Dithia- and Diselenadiazolyl Radicals: Preparation and Structural and Electronic Properties of 1,3-[(E2N2C)C6H4(CN2E2)] (E = S, Se)
The preparation and solid-state characterization of the 1,3-phenylene-bridged bis(dithiadiazolyl) and bis(diselenadiazolyl) diradicals 1,3-[(E2N2C)C6H4(CN2E2)] (E = S, Se) are reported. The isomorphous crystals of 1,3-[(E2N2C)C6H4(CN2E2)] so obtained are tetragonal, space group I41/a. Stacks of diradical molecules, linked vertically in a zigzag fashion through alternaie ends by long E- - -E contacts (mean 3.140/3.284 Ă
, for E = S/Se), are arranged in pinwheellike clusters about the 41 and ÂŻ4 axes, producing complex patterns of interstack E- - -E contacts. Both compounds show the presence of spin defects in the lattice, and there is a very large enhancement in the paramagnetism of the sulfur compound at high temperatures. The selenium compound is a semiconductor, with a room temperature conductivity of 2 Ă 10-4 S cm-1. Solid-state NMR experiments find enhanced relaxation times, which have their origin in the presence of a mobile paramagnetic defect. Extended HĂŒckel band structure calculations show the materials to be semiconductors, with band gaps of about 1.0/0.8 eV for E = S/Se. Although the compounds adopt a columnar structure, the calculations indicate significant interactions between the stacks and the materials exhibit well-developed three dimensionality. The enhanced paramagnetism in the sulfur compound is attributed to the presence of thermally generated phase kinks in the lattice, whereas the selenium compound is classified as an intrinsic semiconductor.