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Hepatocytes constitute the majority of hepatic cells, and play a key role in controlling systemic innate immunity, via pattern-recognition receptors (PRRs) and by synthesizing complement and acute phase proteins. Leishmania infantum , a protozoan parasite that causes human and canine leishmaniasis, infects liver by establishing inside the Kupffer cells. The current study proposes the elucidation of the immune response generated by dog hepatocytes when exposed to L. infantum. Additionally, the impact of adding leishmanicidal compound, meglumine antimoniate (MgA), to parasite-exposed hepatocytes was also addressed. L. infantum presents a high tropism to hepatocytes, establishing strong membrane interactions. The possibility of L. infantum internalization by hepatocytes was raised, but not confirmed. Hepatocytes were able to recognize parasite presence, inducing PRRs [nucleotide oligomerization domain (NOD)1, NOD2 and Toll-like receptor (TLR)2] gene expression and generating a mix pro- and anti-inflammatory cytokine response. Reduction of cytochrome P 450s enzyme activity was also observed concomitant with the inflammatory response. Addition of MgA increased NOD2, TLR4 and interleukin 10 gene expression, indicating an immunomodulatory role for MgA. Hepatocytes seem to have a major role in coordinating liver's innate immune response against L. infantum infection, activating inflammatory mechanisms, but always balancing the inflammatory response in order to avoid cell damage. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnea (OSA) affects approximately 1–3% of pediatric population and is associated with significant morbidity. As adenotonsillar hypertrophy (ATH) is its primary cause in children, elective adenotonsillectomy is the first treatment of choice. Noninvasive ventilation (NIV) has been increasingly considered as an option, mainly for children with complex diseases, ineligible or waiting for surgeries, or after surgery failure.

Calcium and aluminium incorporation into a sodium borosilicate glass with base composition 0.30Na2O 0.46SiO2 0.24B2O3was investigated. Glasses of general compositions (0.30 − x/3.3)Na2O xCaO (0.46 − x/2.2)SiO2 (0.24 − x/4.2)B2O3(Cx) and (0.3 − x/3.3)Na2O xAl2O3 (0.46 − x/2.2)SiO2 (0.24 − x/4.2)B2O3(Ax) were prepared by melt quenching. All the samples were tested for glass-ionomer cement formation. Glasses in the Cxsystem did not yield sustainable cements on mixing at glass to liquid ratios of 2.4 1. The glasses of system Axwere unmixable at glass to liquid ratios between 2.4 1 and 1.5 1, with the exception of the sample with composition x= 0.3, which was mixable at a glass to liquid ratio of 2.4 1, producing a cement with an average compressive strength of 69.3 MPa (σ= 6.1 MPa). 11B, 23Na, 27Al and 29Si magic angle spinning nuclear magnetic resonance spectroscopy was used to characterize the structure of the glass and cement samples. The results showed that the calcium boroaluminosilicate glass compositions have the potential to be used as solid components in the preparation of glass-ionomer cement formulations.

The kinetics of diffusion-controlled triplet−triplet annihilation (TTA) and simultaneous delayed fluorescence (DF) of meso-tetraphenylporphyrin (TPP) in thin films (1−100 nm) of n-decanol (DEC) adsorbed on the external surface of NaA zeolite were studied by the diffuse-reflectance laser flash technique in the temperature range 220−330 K. The value of the TTA bimolecular rate constant (kTTA^L) referred to the DEC volume in the solid samples (with the amount of DEC being ≥10 monolayers) is similar to that measured in neat DEC. At temperatures above the melting point of DEC (280 K), the decrease of the DEC film thickness to one monolayer results in 20-fold increase of kTTA^L which is attributed to the confined reaction volume where TPP is concentrated as well as to the enhanced TPP diffusion in this volume. The DEC monolayers on the NaA external surface are vertically ordered DEC molecules with external hydrocarbon region characterized by enhanced molecular mobility confirmed by solid-state ¹H NMR spectra. The apparent rate of TTA in neat DEC or in bulk DEC multilayers increases by more than 1 order of magnitude with the freezing of DEC and further temperature decrease down to 260 K whereas that in DEC monolayers does not. The apparent kTTA^L value measured far below the melting point of DEC is independent of DEC film thickness and coincides with that in neat frozen DEC which presents some organized monolayers with TPP localized in the vicinity of aliphatic chains.

The structure of Bi2Al4O9has been refined using a combination of X-ray and high-resolution neutron powder diffraction. Iterative simulation of the 27Al MAS solid state NMR data confirms the presence of two Al sites, one octahedral and one tetrahedral, in an approximate 1:1 ratio. The structure of Bi2Al4O9has been refined anisotropically in the orthorhombic space group Pbam, with a=7.7134(1), b=8.1139(2), c=5.6914(1) Å, and Z=2. The refinement terminated with Rwp=17.09% (X ray), 11.44% (neutron); Rex=4.52% (X ray), 3.22% (neutron). The structure consists of edge-sharing columns of AlO6octahedra running parallel to the c-axis. These columns are linked by pairs of apex sharing AlO4tetrahedra, with Bi atoms located between the columns. The Bi 6s2lone pairs point toward vacant sites in the structure. A one-dimensional conductivity mechanism along the c-axis vector is proposed involving these sites.

We present a 13C NMR study of the CN groups in some TCNQ salts, focused on the use of high resolution techniques. We show that a careful analysis of the structural and the electronic features of these systems, allows an appropriate choice of the experimental conditions and consequently a correct analysis of the corresponding spectra.