Expanding the phenotypic and genotypic spectrum of Bietti crystalline dystrophy

Abstract: The rare form of retinal dystrophy, Bietti crystalline dystrophy, is associated with variations in CYP4V2, a member of the cytochrome P450 family. This study reports patients affected by typical and atypical Bietti crystalline dystrophy, expanding the spectrum of this disease. This is an observational case series of patients with a clinical and molecular diagnosis of Bietti crystalline dystrophy that underwent multimodal imaging. Four unrelated patients are described with two known variants, c.802‐8_810del17insGC and c.518T > G (p.Leu173Trp), and one novel missense variant, c.1169G > T (p.Arg390Leu). The patient with the novel homozygous variant had the most severe phenotype resulting in macular hole formation and retinal detachment in both eyes. To the best of our knowledge, there is no association of these features with Bietti crystalline dystrophy. Patient 1 was the youngest patient and had the mildest phenotype with crystals in the retina without chorioretinal atrophy and visual complaints. Patients 2 and 3 presented with fewer crystals and chorioretinal atrophy. These three patients presented a classic phenotype. The fourth patient presented with an atypical and severe phenotype. This study reveals a new genotype and new phenotype associated with this disorder. Keywords: bietti crystalline dystrophy; CYP4V2 protein; genetic testing; missense mutation; insertion‐deletion mutatio

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

BaMoO4:Tb3+ phosphor properties: Synthesis, characterization and photophysical studies

BaMoO4:Tb3+ powders were synthesized by the complex polymerization (CP) method and characterized by powder X-ray diffraction patterns (XRD), Fourier transform infra-Red (FTIR) and Raman spectroscopy as well as photoluminescence (PL) measurements. The results confirmed the presence of a crystalline scheelite-type phase in BaMoO4:TP3+ crystalline powers. Excitation spectra, lambda(em).= 543 nm revealed the predominance of a broad band of charge transfer that was ascribed to the absorption of [MoO4](2-) ionic tetragonal clusters. Emission spectra of BaMoO4:Tb3+ samples (lambda(ex.)= 294 nm) have a group of sharp emission bands (456-487 nm; 543-546 nm; 581-589 nm and 617-620 nm) assigned to the D-5(4) -> F-7(6), D-5(4) -> F-7(5), D-5(4) -> F-7(4) and D-5(4) -> F-7(3) transitions of Tb3+ ions, respectively. The samples show the exponential decay curves of D-5(4) -> F-7(5) transition, lambda(exc). = 294 nm and lambda(em) = 543 nm, where the greater decay time was evaluated as 1.07 ms for the BaMoO4:Tb3+ annealed at 900 degrees C. (C) 2011 Elsevier B.V. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Effect of process parameters on photophysical properties and barium molybdate phosphors characteristics

Barium molybdate particles (BaMoO4) with uniform shapes have applications in various fields such as phosphors, optical fibers, scintillators, magnets and catalysts. in this study, two synthesis methods (microwave-assisted hydrothermal (MAH) and Complex Polymerization (CP)) were used to prepare BaMoO4 particles. the effect of the applied synthesis methodology and experimental parameters on the morphology, particle size, sample uniformity and optical properties of the BaMoO4 were studied. Scheelite-type single crystalline structures of BaMoO4 were identified by X-ray diffraction (XRD) as well as Raman and Fourier transform infrared spectroscopy (FTIR). Octahedral morphologies were characterized by field-emission scanning electron microscopy (FE-SEM). Photoluminescence (PL) spectra of the samples exhibited different emission properties which indicates a relationship with surface defect states (shallow and deep level defects) where interfaces populate additional levels in the band gap. Electronic order-disorder at short- and intermediate-ranges is generated by utilizing the synthesis method and can be modified by applied experimental parameters. If the particle size and morphology are controlled, deep and shallow defects can be controlled, and PL properties can be modified accordingly with the optical properties desired. (C) 2014 Published by Elsevier Ltd and Techna Group S.r.l.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)UNIFESP, Dept Ciencias Exatas & Terra, BR-09972270 Diadema, SP, BrazilUniv Fed Sao Carlos, Dept Quim, LIEC, BR-13565905 Sao Carlos, SP, BrazilUniv Fed Rio Grande do Norte, Dept Mat Engn, BR-59072970 Natal, RN, BrazilUniv Fed Uberlandia, Inst Quim, BR-38400902 Uberlandia, MG, BrazilUniv São Paulo, Inst Fis Sao Carlos, BR-13566590 Sao Carlos, SP, BrazilUNIFESP, Dept Ciencias Exatas & Terra, BR-09972270 Diadema, SP, BrazilCNPq: 576563/2008-0Web of Scienc