Hallym University

About: Hallym University is a education organization based out in Chuncheon, South Korea. It is known for research contribution in the topics: Population & Medicine. The organization has 10605 authors who have published 18891 publications receiving 302498 citations.

Clinical course of untreated cerebral cavernous malformations: a meta-analysis of individual patient data.

Abstract: Summary Background Cerebral cavernous malformations (CCMs) can cause symptomatic intracranial haemorrhage (ICH), but the estimated risks are imprecise and predictors remain uncertain. We aimed to obtain precise estimates and predictors of the risk of ICH during untreated follow-up in an individual patient data meta-analysis. Methods We invited investigators of published cohorts of people aged at least 16 years, identified by a systematic review of Ovid MEDLINE and Embase from inception to April 30, 2015, to provide individual patient data on clinical course from CCM diagnosis until first CCM treatment or last available follow-up. We used survival analysis to estimate the 5-year risk of symptomatic ICH due to CCMs (primary outcome), multivariable Cox regression to identify baseline predictors of outcome, and random-effects models to pool estimates in a meta-analysis. Findings Among 1620 people in seven cohorts from six studies, 204 experienced ICH during 5197 person-years of follow-up (Kaplan-Meier estimated 5-year risk 15·8%, 95% CI 13·7–17·9). The primary outcome of ICH within 5 years of CCM diagnosis was associated with clinical presentation with ICH or new focal neurological deficit (FND) without brain imaging evidence of recent haemorrhage versus other modes of presentation (hazard ratio 5·6, 95% CI 3·2–9·7) and with brainstem CCM location versus other locations (4·4, 2·3–8·6), but age, sex, and CCM multiplicity did not add independent prognostic information. The 5-year estimated risk of ICH during untreated follow-up was 3·8% (95% CI 2·1–5·5) for 718 people with non-brainstem CCM presenting without ICH or FND, 8·0% (0·1–15·9) for 80 people with brainstem CCM presenting without ICH or FND, 18·4% (13·3–23·5) for 327 people with non-brainstem CCM presenting with ICH or FND, and 30·8% (26·3–35·2) for 495 people with brainstem CCM presenting with ICH or FND. Interpretation Mode of clinical presentation and CCM location are independently associated with ICH within 5 years of CCM diagnosis. These findings can inform decisions about CCM treatment. Funding UK Medical Research Council, Chief Scientist Office of the Scottish Government, and UK Stroke Association.

The origin of antiferroelectricity in PbZrO3

Abstract: Antiferroelectrics are essential ingredients for the widely applied piezoelectric and ferroelectric materials: the most common ferroelectric, lead zirconate titanate is an alloy of the ferroelectric lead titanate and the antiferroelectric lead zirconate. Antiferroelectrics themselves are useful in large digital displacement transducers and energy-storage capacitors. Despite their technological importance, the reason why materials become antiferroelectric has remained allusive since their first discovery. Here we report the results of a study on the lattice dynamics of the antiferroelectric lead zirconate using inelastic and diffuse X-ray scattering techniques and the Brillouin light scattering. The analysis of the results reveals that the antiferroelectric state is a 'missed' incommensurate phase, and that the paraelectric to antiferroelectric phase transition is driven by the softening of a single lattice mode via flexoelectric coupling. These findings resolve the mystery of the origin of antiferroelectricity in lead zirconate and suggest an approach to the treatment of complex phase transitions in ferroics.

β-Carotene inhibits inflammatory gene expression in lipopolysaccharide-stimulated macrophages by suppressing redox-based NF-κB activation

Abstract: β-Carotene has shown antioxidant and antiinflammatory activities; however, its molecular mechanism has not been clearly defined. We exa - mined in vitro and in vivo regulatory function of β-carotene on the production of nitric oxide (NO) and PGE₂ as well as expression of inducible NO synthase (iNOS), cyclooxygenase-2, TNF-α, and IL-1β. β-Carotene inhibited the expression and production of these inflammatory mediators in both LPSstimulated RAW264.7 cells and primary macrophages in a dose-dependent fashion as well as in LPS-administrated mice. Furthermore, this com - pound suppressed NF-κB activation and iNOS promoter activity in RAW264.7 cells stimulated with LPS. β-Carotene blocked nuclear translocation of NF-κB p65 subunit, which correlated with its inhibitory effect on IκBα phosphorylation and degradation. This compound directly blocked the intracellular accumulation of reactive oxygen species in RAW264.7 cells stimulated with LPS as both the NADPH oxidase inhibitor diphenylene iodonium and antioxidant pyrrolidine dithiocarbamate did. The inhibition of NADPH oxidase also inhibited NO production, iNOS expression, and iNOS promoter activity. These results suggest that β-carotene possesses anti-inflammatory activity by functioning as a potential inhibitor for redox-based NF-κB activation, probably due to its antioxidant activity.