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Background: Little is known about the pathogenesis of scleromyxedema, a life‐threatening fibromucinosis disease with immunological dysregulation. Objectives: To investigate on T‐cell phenotype, function and cytokine biology in search of new insights supporting the immunopathogenesis of the disease. Methods: We analysed the frequency of circulating lymphocyte subsets, the T‐cell maturation stage, the generation of antigen‐specific T‐cell lines and T‐cell cytokine secretion. Results: The analysis of T‐cell maturation stage and the TCR spectratyping findings revealed that scleromyxedema patients showed clear immunological signs of long‐lasting immune system activation and stimulation leading to a skewed T‐cell repertoire. Moreover, these analyses showed that both CD4+ and CD8+ T cells from scleromyxedema patients have a profound deficiency (even after stimulation) relatively to the production of IFN‐γ and IL17 with respect to healthy donor control cells, while they are massively skewed towards IL4 secretion after stimulation. Conclusions: Our data indicate that a chronic Th2‐skewed T‐cell response against an unknown target antigen leading to abnormally high IL4 secretion, a pro‐fibrotic cytokine, is a main immunological hallmark of scleromyxedema patients. These results, never reported before, may have a translational therapeutic value due to the availability of anti‐IL4 agents such as dupilumab. [ABSTRACT FROM AUTHOR]

This work describes the production of electrically conductive nanocomposites based on thermoplastic polyurethane (TPU) filled with montmorillonite-dodecylbenzenesulfonic acid-doped polypyrrole (Mt-PPy.DBSA) prepared by melt blending in an internal mixer. The electrical conductivity, morphology as well as the rheological properties of TPU/Mt- PPy.DBSA nanocomposites were evaluated and compared with those of TPU nanocomposites containing different conductive fillers, such as polypyrrole doped with hydrochloride acid (PPy.Cl) or dodecylbenzenesulfonic acid (PPy.DBSA) or montmorillonite-hydrochloride acid-doped polypyrrole (Mt-PPy.Cl), prepared with the same procedure. The TPU/Mt- PPy.DBSA nanocomposites display a very sharp insulator-conductor transition and the electrical percolation threshold was about 10 wt% of Mt-PPy.DBSA, which was significantly lower than those found for TPU/Mt-PPy.Cl, TPU/PPy.Cl and TPU/PPy.DBSA. Morphological analysis highlights that Mt-PPy.DBSA filler was better distributed and dispersed in the TPU matrix, forming a denser conductive network when compared to Mt-PPy.Cl, PPy.Cl and PPy.DBSA fillers. This morphology can be attributed to the higher site-specific interaction between TPU matrix and Mt-PPy.DBSA. The present study demonstrated the potential use of Mt-PPy.DBSA as new promising conductive nanofiller to produce highly conductive polymer nanocomposites with functional properties. [ABSTRACT FROM AUTHOR]

We investigated whether genetic variations of the beta-2 adrenergic receptor (ADRB2) modulate the haemodynamic response following spinal anaesthesia for caesarean delivery. We focused on the effects of haplotypes formed by combinations of the Arg16Gly and Gln27Glu polymorphisms. Clinical data from 143 healthy parturients were collected. Only the ArgGln haplotype appeared to influence the risk of hypotension, most probably through a recessive mode of inheritance (p = 0.027). Therefore, patients were grouped according to ArgGln homozygosity in two groups: presence of one or no copies of the haplotype (n = 120) or two copies of the haplotype (n = 23). Both groups presented similar baseline characteristics. Comparatively, patients homozygous for the ArgGln haplotype presented consistently higher blood pressure levels throughout the evaluation period (p = 0.001 for systolic arterial pressure variation from baseline). In conclusion, our results demonstrate that haplotype variations of the the ADRB2 modulate the haemodynamic response following spinal anaesthesia for caesarean delivery. [ABSTRACT FROM AUTHOR]

Free-standing films of bacterial cellulose (BC) and polyaniline (PAni) (BC/PAni) composites with high electrical conductivity values (0.9 S cm) and good mechanical properties (40 MPa) were prepared through in situ oxidative chemical polymerization of aniline (Ani) on the surface of synthesized BC nanofibers by using FeCl·6HO, as oxidant. The influence of polymerization conditions such as oxidant content, protonic acid, and reaction time on electrical conductivity, morphological, tensile properties and thermal stability of the BC/PAni composites was investigated. Electrical conductivities of BC/PAni composites increased with increasing reaction time due to the formation of a continuous layer that completely coated the nanofiber surface. FTIR spectra of BC/PAni composites produced with and without protonic acid exhibited overlapped absorption bands of both BC and PAni, except for quinoid and benzoid bending modes of PAni. The in situ oxidative chemical polymerization gives rise to conducting membranes with the surface constituted by different PAni content, as indicated through CHN elemental analysis. The crystalline structure of BC was not affected by the incorporation of PAni. Scanning electron microscopy analysis of the composites revealed that PAni consisted of nanoparticles around 70 nm in mean size to form a continuous coating that encapsulates the BC nanofibers. The BC/PAni composites obtained by the method described in this work have interesting properties that may find important technological applications such as sensors, electronic devices, intelligent clothes, flexible electrodes and tissue engineering scaffolds. [ABSTRACT FROM AUTHOR]

Low density polyethylene (LDPE) and either isotactic polypropilene (IPP) or a copolymer of isotactic polypropilene with 3% of ethylene (CPP) were blended, and analyzed with X-rays, differential thermal calorimetry, dynamic mechanical analysis, and transport properties of dichloromethane vapour at different activities. The results show that polyethylene and polypropylene crystallize in different domains in the usual crystalline forms (orthorhombic and monoclinic respectively). Also the amorphous phases are not miscible; moreover in the blend LDPE-IPP, in which PE crystallize less, the transport of the vapours occurs mainly through polyethylene, whereas the opposite is true in the blend LDPE-CPP, in which polypropylene crystallizes less. The sorption properties are in agreement with the additivity of sorption of the two amorphous phases. [ABSTRACT FROM AUTHOR]