Silica Nanoparticles Inhibit Responses to ATP in Human Airway Epithelial 16HBE Cells

Because of their low cost and easy production, silica nanoparticles (SiNPs) are widely used in multiple manufacturing applications as anti-caking, densifying and hydrophobic agents. However, this has increased the exposure levels of the general population and has raised concerns about the toxicity of this nanomaterial. SiNPs affect the function of the airway epithelium, but the biochemical pathways targeted by these particles remain largely unknown. Here we investigated the effects of SiNPs on the responses of 16HBE14o- cultured human bronchial epithelial (16HBE) cells to the damage-associated molecular pattern ATP, using fluorometric measurements of intracellular Ca²⁺ concentration. Upon stimulation with extracellular ATP, these cells displayed a concentration-dependent increase in intracellular Ca²⁺, which was mediated by release from intracellular stores. SiNPs inhibited the Ca²⁺ responses to ATP within minutes of application and at low micromolar concentrations, which are significantly faster and more potent than those previously reported for the induction of cellular toxicity and pro-inflammatory responses. SiNPs-induced inhibition is independent from the increase in intracellular Ca²⁺ they produce, is largely irreversible and occurs via a non-competitive mechanism. These findings suggest that SiNPs reduce the ability of airway epithelial cells to mount ATP-dependent protective responses.     

Gangliosides as Biomarkers of Human Brain Diseases: Trends in Discovery and Characterization by High-Performance Mass Spectrometry

Gangliosides are effective biochemical markers of brain pathologies, being also in the focus of research as potential therapeutic targets. Accurate brain ganglioside mapping is an essential requirement for correlating the specificity of their composition with a certain pathological state and establishing a well-defined set of biomarkers. Among all bioanalytical methods conceived for this purpose, mass spectrometry (MS) has developed into one of the most valuable, due to the wealth and consistency of structural information provided. In this context, the present article reviews the achievements of MS in discovery and structural analysis of gangliosides associated with severe brain pathologies. The first part is dedicated to the contributions of MS in the assessment of ganglioside composition and role in the specific neurodegenerative disorders: Alzheimer’s and Parkinson’s diseases. A large subsequent section is devoted to cephalic disorders (CD), with an emphasis on the MS of gangliosides in anencephaly, the most common and severe disease in the CD spectrum. The last part is focused on the major accomplishments of MS-based methods in the discovery of ganglioside species, which are associated with primary and secondary brain tumors and may either facilitate an early diagnosis or represent target molecules for immunotherapy oriented against brain cancers.     

Magnetic composites based on bovine serum albumin and poly(aspartic acid)

In this investigation, magnetic polymer composites were developed by using a magnetic field‐assisted strategy. To create the composite, an interpolymeric complex based on bovine serum albumin and poly(aspartic acid) used as a polymer matrix was mixed with pre‐synthesized magnetite nanoparticles and then exposed to a high‐frequency magnetic field. The formation of such composite was confirmed by FTIR‐spectra, scanning electron micrographs, dynamic light scattering measurements, and magnetic susceptibility analysis. The results revealed that the materials have a superparamagnetic behavior and an average hydrodynamic size ranging from 220 to 580 nm. The polymer matrix improved the colloidal stability of the magnetic filler. The proposed composites are expected to be promising candidates for biomedical applications, such as drug delivery systems. POLYM. ENG. SCI., 59:1409–1415 2019. © 2019 Society of Plastics Engineers     

Influence of B-site cations ordering on magnetization and dielectric relaxations in Li–Ni spinel ferrites

Ho-substituted Li–Ni ferrites with composition L i_1.2Ni_0.4Ho_xFe_2-xO₄; 0≤ x ≤ 0.15 were synthesized by a self-ignited sol-gel process. An annealing temperature of 950 °C is estimated via thermal-gravimetric (TGA) analysis. X-ray diffraction (XRD) scans have confirmed the formation of the ferrite phase with a spinel structure in all samples. Substitution of Ho ions on the B-site significantly reduced the porosity from 38 -to 23% and the crystallite size from 23.4 -to 21.7 nm. Microstructural analysis revealed a denser structure with an increase in Ho content. Dielectric results showed that both the dielectric loss and dielectric constant depict a nonlinear variation with the addition of Ho. Complex impedance behavior with a single semicircle for all samples suggests the predominant effect of the grain boundary mechanism. The substitution of Ho ions in place of Fe ions significantly decreased the electrical conductivity. The anisotropic Ho³⁺ ions reinforce the L-S coupling which consequently enhanced the coercive force from 145 -to 389 Oe, and thus the anisotropy constant.     

Lack of GABARAP-Type Proteins Is Accompanied by Altered Golgi Morphology and Surfaceome Composition

GABARAP (γ-aminobutyric acid type A receptor-associated protein) and its paralogues GABARAPL1 and GABARAPL2 comprise a subfamily of autophagy-related Atg8 proteins. They are studied extensively regarding their roles during autophagy. Originally, however, especially GABARAPL2 was discovered to be involved in intra-Golgi transport and homotypic fusion of post-mitotic Golgi fragments. Recently, a broader function of mammalian Atg8s on membrane trafficking through interaction with various soluble N-ethylmaleimide-sensitive factor-attachment protein receptors (SNAREs) was suggested. By immunostaining and microscopic analysis of the Golgi network, we demonstrate the importance of the presence of individual GABARAP-type proteins on Golgi morphology. Furthermore, triple knockout (TKO) cells lacking the whole GABARAP subfamily showed impaired Golgi-dependent vesicular trafficking as assessed by imaging of fluorescently labelled ceramide. With the Golgi apparatus being central within the secretory pathway, we sought to investigate the role of the GABARAP-type proteins for cell surface protein trafficking. By analysing the surfaceome composition of TKOs, we identified a subset of cell surface proteins with altered plasma membrane localisation. Taken together, we provide novel insights into an underrated aspect of autophagy-independent functions of the GABARAP subfamily and recommend considering the potential impact of GABARAP subfamily proteins on a plethora of processes during experimental analysis of GABARAP-deficient cells not only in the autophagic context.     

Aggression,impulsivity, and health functioning in a veteran population: equivalency and test–retest reliability of computerized and paper-and-pencil administrations

The present study examined the equivalency and test–retest reliability of two administration methods (paper-and-pencil and computerized) of the Aggression Questionnaire (AQ), Barratt Impulsiveness Scale-11 (BIS-11), and SF-36 Health Survey (SF-36) in a sample of 97 veterans. The two-week test–retest reliability for the conventional paper-and-pencil administrations of the AQ, BIS-11, and the SF-36 in the veteran population were generally reliable and comparable to the test–retest reliability of these measures noted in the research for other populations. Equivalence of the computer vs. paper-and-pencil administrations were examined and results indicated that for the AQ, ICCs for all four subscales and total score were substantially lower for the PC administration. For the BIS-11, ICCs were comparable with the exception of the Motor subscale, which was lower in the PC condition. For the SF-36, two of the domains were higher in the PC condition, with four more being comparable. Overall, the computerized administration of the BIS-11 and SF-36 was found to be equivalent to the “gold standard” paper-and-pencil administration of these measures and can be utilized successfully among veterans. The computerized administration of the AQ, however, was not found to be equivalent to the paper-and-pencil administration of the measure.     

The best task allocation process is to decide on one’s own: effects of the allocation agent in human–robot interaction on perceived work characteristics and satisfaction

Cognition, Technology & Work - New technologies are ever evolving and have the power to change human work for the better or the worse depending on the implementation. For human–robot...     

The photochemical stability of oil from Evening Primrose seeds

Photochemical reactions taking place in oil to which was added chlorophyll a as well as β-carotene and subjected to illumination for different times, have been investigated by measuring the absorption, fluorescence emission and fluorescence excitation spectra. The addition of carotene was found to greatly lower chlorophyll degradation as a result of the quenching of chlorophyll triplet states; however, its presence also influence the generation of other oil photoproducts. A comparison of the photoreactions induced by the light absorbed predominantly by chlorophyll-like pigments with those induced by bright light covering practically the whole visible region implies that the majority of the photoreactions occur with the participation of excited chlorophyll molecules.

The singlet excitation energy of β-carotene is not transferred to chlorophyll. The quenching of photochemically active triplets of chlorophyll alters the extent of oil degradation imparted by this excitation. The absorption and emission spectra of the oil degradation products are superimposable and, therefore, the quantitative analysis of the products is not easy. The generation of malonic dialdehyde, which is the main product of oil degradation, is a little slower in the presence of carotenoids, which suggests that some components within the oil protect against photooxidation by the addition of carotenoids.