Quantification of Sunscreen Ethylhexyl Triazone in Topical Skin-Care Products by Normal-Phase TLC/Densitometry

Ethylhexyl triazone (ET) was separated from other sunscreens such as avobenzone, octocrylene, octyl methoxycinnamate, and diethylamino hydroxybenzoyl hexyl benzoate and from parabens by normal-phase HPTLC on silica gel 60 as stationary phase. Two mobile phases were particularly effective: (A) cyclohexane-diethyl ether 1 : 1 (v/v) and (B) cyclohexane-diethyl ether-acetone 15 : 1 : 2 (v/v/v) since apart from ET analysis they facilitated separation and quantification of other sunscreens present in the formulations. Densitometric scanning was performed at 300 nm. Calibration curves for ET were nonlinear (second-degree polynomials), with R > 0.998. For both mobile phases limits of detection (LOD) were 0.03 and limits of quantification (LOQ) 0.1 μg spot−1. Both methods were validated

Clinical correlates of rhinovirus infection in preschool asthma

Background Investigation of preschool asthma is important since not all children outgrow their illness during this age. Data are scarce on the role of rhinovirus (RV) infections in this patient group. Objectives To investigate the role of RV infections in preschool asthma: (i) susceptibility factors, (ii) clinical course, and (iii) medium-term outcome. Methods A total of 130 asthmatic children aged 4-6 years from the multinational PreDicta cohort were prospectively followed for a 12-month period. Allergy tests and a standard health questionnaire were carried out at study entry. Respiratory virus presence in nasopharyngeal washes was studied at illness visits and at 3 scheduled visits. Results At study entry, mean age of the children was 5.3 years. Of 571 visits, 54% were positive for any virus and 39% for RV. Patient characteristics were only assessed with RV infection due to low number of other viruses. The use of supplementary vitamin D was inversely associated with RV infection (P < .05). RV infection was associated with more severe course of acute illness in terms of more severe nighttime coughing, more sleep disturbances, and more days with runny nose (allP < .05). RV infection was also associated with more severe disease course during the 12-month follow-up in terms of more nights with awakenings and more days of exercise-related symptoms (bothP < .05). Conclusions Vitamin D supplementation may have an anti-rhinovirus effect. Both short- and medium-term outcomes suggest RV infection to be an important clinical marker of instable preschool asthma

Quantitative oculomotor assessment in hereditary ataxia: systematic review and consensus by the ataxia global initiative working group on digital-motor biomarkers

Oculomotor deficits are common in hereditary ataxia, but disproportionally neglected in clinical ataxia scales and as outcome measures for interventional trials. Quantitative assessment of oculomotor function has become increasingly available and thus applicable in multicenter trials and offers the opportunity to capture severity and progression of oculomotor impairment in a sensitive and reliable manner. In this consensus paper of the Ataxia Global Initiative Working Group On Digital Oculomotor Biomarkers, based on a systematic literature review, we propose harmonized methodology and measurement parameters for the quantitative assessment of oculomotor function in natural-history studies and clinical trials in hereditary ataxia. MEDLINE was searched for articles reporting on oculomotor/vestibular properties in ataxia patients and a study-tailored quality-assessment was performed. One-hundred-and-seventeen articles reporting on subjects with genetically confirmed (n=1134) or suspected hereditary ataxia (n=198), and degenerative ataxias with sporadic presentation (n=480) were included and subject to data extraction. Based on robust discrimination from controls, correlation with disease-severity, sensitivity to change, and feasibility in international multicenter settings as prerequisite for clinical trials, we prioritize a core-set of five eye-movement types: (i) pursuit eye movements, (ii) saccadic eye movements, (iii) fixation, (iv) eccentric gaze holding, and (v) rotational vestibulo-ocular reflex. We provide detailed guidelines for their acquisition, and recommendations on the quantitative parameters to extract. Limitations include low study quality, heterogeneity in patient populations, and lack of longitudinal studies. Standardization of quantitative oculomotor assessments will facilitate their implementation, interpretation, and validation in clinical trials, and ultimately advance our understanding of the evolution of oculomotor network dysfunction in hereditary ataxias

Clinical correlates of rhinovirus infection in preschool asthma

Background Investigation of preschool asthma is important since not all children outgrow their illness during this age. Data are scarce on the role of rhinovirus (RV) infections in this patient group. Objectives To investigate the role of RV infections in preschool asthma: (i) susceptibility factors, (ii) clinical course, and (iii) medium-term outcome. Methods A total of 130 asthmatic children aged 4-6 years from the multinational PreDicta cohort were prospectively followed for a 12-month period. Allergy tests and a standard health questionnaire were carried out at study entry. Respiratory virus presence in nasopharyngeal washes was studied at illness visits and at 3 scheduled visits. Results At study entry, mean age of the children was 5.3 years. Of 571 visits, 54% were positive for any virus and 39% for RV. Patient characteristics were only assessed with RV infection due to low number of other viruses. The use of supplementary vitamin D was inversely associated with RV infection (P < .05). RV infection was associated with more severe course of acute illness in terms of more severe nighttime coughing, more sleep disturbances, and more days with runny nose (allP < .05). RV infection was also associated with more severe disease course during the 12-month follow-up in terms of more nights with awakenings and more days of exercise-related symptoms (bothP < .05). Conclusions Vitamin D supplementation may have an anti-rhinovirus effect. Both short- and medium-term outcomes suggest RV infection to be an important clinical marker of instable preschool asthma

C9orf72 hexanucleotide repeat expansion found in suspected spinobulbar muscular atrophy (SBMA)

Introduction. The expansion of a hexanucleotide GGGGCC repeat (G4C2) in the C9orf72 locus is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). In addition, C9orf72 expansion has also been detected in patients with a clinical manifestation of Parkinson’s Disease (PD), Alzheimer’s Disease (AD), Huntington’s Disease (HD), and ataxic disorders. Material and methods. A total of 1,387 patients with clinically suspected ALS, HD or spinal and bulbar muscular atrophy (SBMA) were enrolled, and the prevalence of C9orf72 expansions was estimated. Results. The hexanucleotide expansion accounted for 3.7% of the ALS patients, 0.2% of the HD suspected patients with excluded HTT mutation, and 1.3% of the suspected SBMA patients with excluded mutation in AR gene. Conclusions: This is the first report revealing the presence of C9orf72 expansion in patients with a suspected SBMA diagnosis. Consequently, we advise testing for C9orf72 expansion in patients presenting with the SBMA phenotype and a genetically unsolved diagnosis

GaN Nanowire Array for Charge Transfer in Hybrid GaN/P3HT:PC71BM Photovoltaic Heterostructure Fabricated on Silicon

We demonstrate that a GaN nanowire array can be used for efficient charge transfer between the organic photovoltaic layer and silicon in a Si/GaN/P3HT:PC71BM inverted hybrid heterostructure. The band alignment of such a material combination is favorable to facilitate exciton dissociation, carrier separation and electron transport into Si. The ordered nature of the GaN array helps to mitigate the intrinsic performance limitations of the organic active layer. The dependence of photovoltaic performance enhancement on the morphology of the nanostructure with nanowire diameters 30, 50, 60, 100 and 150 nm was studied in detail. The short circuit current was enhanced by a factor of 4.25, while an open circuit voltage increase by 0.32 volts was achieved compared to similar planar layers

Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

International audienceIn urban areaswith high fallout of airborne particles,metal uptake by plantsmainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results showthat Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO4, chemical forms that were also observed in pristine particles, newspecies were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO3. In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to better assess the health risks involved

Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

International audienceIn urban areaswith high fallout of airborne particles,metal uptake by plantsmainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results showthat Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO4, chemical forms that were also observed in pristine particles, newspecies were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO3. In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to better assess the health risks involved

Influence of Growth Polarity Switching on the Optical and Electrical Properties of GaN/AlGaN Nanowire LEDs

For the development and application of GaN-based nanowire structures, it is crucial to understand their fundamental properties. In this work, we provide the nano-scale correlation of the morphological, electrical, and optical properties of GaN/AlGaN nanowire light emitting diodes (LEDs), observed using a combination of spatially and spectrally resolved cathodoluminescence spectroscopy and imaging, electron beam-induced current microscopy, the nano-probe technique, and scanning electron microscopy. To complement the results, the photo- and electro-luminescence were also studied. The interpretation of the experimental data was supported by the results of numerical simulations of the electronic band structure. We characterized two types of nanowire LEDs grown in one process, which exhibit top facets of different shapes and, as we proved, have opposite growth polarities. We show that switching the polarity of nanowires (NWs) from the N- to Ga-face has a significant impact on their optical and electrical properties. In particular, cathodoluminescence studies revealed quantum wells emissions at about 3.5 eV, which were much brighter in Ga-polar NWs than in N-polar NWs. Moreover, the electron beam-induced current mapping proved that the p&ndash;n junctions were not active in N-polar NWs. Our results clearly indicate that intentional polarity inversion between the n- and p-type parts of NWs is a potential path towards the development of efficient nanoLED NW structures