The Impact of Polyoxyethylene Sorbitan Surfactants in the Microstructure and Rheological Behaviour of Emulsions Made With Melted Fat From Cupuassu (<Emphasis Type="Italic">Theobroma grandiflorum</Emphasis>)

Cupuassu fat is a good candidate for partial substitution of cocoa butter in many products, including emulsions. However, for such use it is necessary to know the characteristics of the products prepared with cupuassu fat. Therefore, the main goal of this work is to characterize emulsions prepared with cupuassu fat using the surfactants Tween^® 60, Tween^® 80 and Tween^® 85 as emulsifiers. The emulsions were prepared at 43 °C with addition of 0.5 or 1.5 % (w/v) of surfactant and compared with an emulsion without surfactant. All emulsions were analysed by conductivity, stability, pH, optical microscopy, rheology and oxidative stability. It was verified that the emulsions prepared with Tween^® 60 and Tween^® 80 have higher stability, smaller droplet size and higher apparent viscosity. Also, these properties are positively influenced by the concentration of the surfactant. On the other hand, emulsions prepared with Tween 85 or without surfactant reached unsatisfactory results. The rheological behaviour of the emulsions was adequately described by both Herschel-Bulkley and Mizhari-Berki models revealing pseudoplastic character. These emulsions also present strong gel behaviour, with storage modulus higher than loss modulus. In conclusion, cupuassu fat can be used as oil phase for emulsions products and this characterization helps to understand their behaviour in order to increase their use in food industry.     

Hyperbranched polyglycerols,obtained from environmentally benign monomer,as reactive clays inhibitors for water‐based drilling fluids

To prevent the degradation of the borehole and also the disintegration and dispersion of drilled cuttings, different shale stabilizing additives are used in water‐based drilling fluids (WBFs). Glycols, poly(ethylene glycol), glycerols, and polyglycerol derivatives, also called polyols, have been used to inhibit shales containing reactive clays in WBF. These additives are normally used in conjunction with KCl to reduce clay swelling and dispersion of drilled cuttings. Highly branched polymers have become an important field in current polymer science. Such materials typically exhibit compact, globular structures in combination with an exceptionally high number of sites with functional groups. They have unique properties that differ significantly from their linear counterparts, and the hyperbranched polyglycerol (hPG) is an important hyperbranched polymer that can be produced from an environmentally benign monomer, the glycerol carbonate. In this article, the clay inhibitive properties of hPG were evaluated by different test methods including bentonite inhibition test, cuttings recovery, and X‐ray diffraction measurements. The results show that the hPG has a great potential to be used as an environmental friendly inhibitor additive in WBFs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40384.     

From Molecules to Behavior in Long-Term Inorganic Mercury Intoxication: Unraveling Proteomic Features in Cerebellar Neurodegeneration of Rats

Mercury is a severe environmental pollutant with neurotoxic effects, especially when exposed for long periods. Although there are several evidences regarding mercury toxicity, little is known about inorganic mercury (IHg) species and cerebellum, one of the main targets of mercury associated with the neurological symptomatology of mercurial poisoning. Besides that, the global proteomic profile assessment is a valuable tool to screen possible biomarkers and elucidate molecular targets of mercury neurotoxicity; however, the literature is still scarce. Thus, this study aimed to investigate the effects of long-term exposure to IHg in adult rats’ cerebellum and explore the modulation of the cerebellar proteome associated with biochemical and functional outcomes, providing evidence, in a translational perspective, of new mercury toxicity targets and possible biomarkers. Fifty-four adult rats were exposed to 0.375 mg/kg of HgCl₂ or distilled water for 45 days using intragastric gavage. Then, the motor functions were evaluated by rotarod and inclined plane. The cerebellum was collected to quantify mercury levels, to assess the antioxidant activity against peroxyl radicals (ACAPs), the lipid peroxidation (LPO), the proteomic profile, the cell death nature by cytotoxicity and apoptosis, and the Purkinje cells density. The IHg exposure increased mercury levels in the cerebellum, reducing ACAP and increasing LPO. The proteomic approach revealed a total 419 proteins with different statuses of regulation, associated with different biological processes, such as synaptic signaling, energy metabolism and nervous system development, e.g., all these molecular changes are associated with increased cytotoxicity and apoptosis, with a neurodegenerative pattern on Purkinje cells layer and poor motor coordination and balance. In conclusion, all these findings feature a neurodegenerative process triggered by IHg in the cerebellum that culminated into motor functions deficits, which are associated with several molecular features and may be related to the clinical outcomes of people exposed to the toxicant.     

Developing conductive immiscible polystyrene/polypropylene blends with a percolated conducting polyaniline/polyamide filler by tuning its specific interactions with the styrene-based triblock compatibilizer grafted with maleic anhydride

An approach to induce conductivity in immiscible polystyrene/polypropylene (PS/PP) blends is described using a percolated conducting polyaniline/polyamide (PANI/PA) filler combined with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene-graft-maleic anhydride compatibilizer. The approach is based on the ability of the compatibilizer to concomitantly stabilize the cocontinuous morphology and to improve the state of dispersion of the PANI/PA filler. Selective localization of PANI/PA in the PS phase with improved filler dispersion is achieved with the optimal master batch (MB) preparation technique followed by its optimized sequence addition to the blend components. This results in an increase in the dc conductivity by six decades as compared with that of the neat compatibilized blend at an effective 4.8-wt % PANI concentration. An investigation of the effect of functionality and concentration of the filler and the compatibilizer on the filler connectivity in the blend is performed. The prevailing specific interactions are analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis of the MBs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48433.     

COVID-19 and Lung Mast Cells: The Kallikrein–Kinin Activation Pathway

Mast cells (MCs) have relevant participation in inflammatory and vascular hyperpermeability events, responsible for the action of the kallikrein–kinin system (KKS), that affect patients inflicted by the severe form of COVID-19. Given a higher number of activated MCs present in COVID-19 patients and their association with vascular hyperpermeability events, we investigated the factors that lead to the activation and degranulation of these cells and their harmful effects on the alveolar septum environment provided by the action of its mediators. Therefore, the pyroptotic processes throughout caspase-1 (CASP-1) and alarmin interleukin-33 (IL-33) secretion were investigated, along with the immunoexpression of angiotensin-converting enzyme 2 (ACE2), bradykinin receptor B1 (B1R) and bradykinin receptor B2 (B2R) on post-mortem lung samples from 24 patients affected by COVID-19. The results were compared to 10 patients affected by H1N1pdm09 and 11 control patients. As a result of the inflammatory processes induced by SARS-CoV-2, the activation by immunoglobulin E (IgE) and degranulation of tryptase, as well as Toluidine Blue metachromatic (TB)-stained MCs of the interstitial and perivascular regions of the same groups were also counted. An increased immunoexpression of the tissue biomarkers CASP-1, IL-33, ACE2, B1R and B2R was observed in the alveolar septum of the COVID-19 patients, associated with a higher density of IgE⁺ MCs, tryptase⁺ MCs and TB-stained MCs, in addition to the presence of intra-alveolar edema. These findings suggest the direct correlation of MCs with vascular hyperpermeability, edema and diffuse alveolar damage (DAD) events that affect patients with a severe form of this disease. The role of KKS activation in events involving the exacerbated increase in vascular permeability and its direct link with the conditions that precede intra-alveolar edema, and the consequent DAD, is evidenced. Therapy with drugs that inhibit the activation/degranulation of MCs can prevent the worsening of the prognosis and provide a better outcome for the patient.     

New Poly(N-isopropylacrylamide-butylacrylate) Copolymer Biointerfaces and Their Characteristic Influence on Cell Behavior In Vitro

Designing and obtaining new synthetic smart biointerfaces with specific and controlled characteristics relevant for applications in biomedical and bioengineering domains represents one of the main challenges in these fields. In this work, Matrix-Assisted Pulsed Laser Evaporation (MAPLE) is used to obtain synthetic biointerfaces of poly(N-isopropyl acrylamide-butyl acrylate) p(NIPAM-BA) copolymer with different characteristics (i.e., roughness, porosity, wettability), and their effect on normal HEK 293 T and murine melanoma B16-F1 cells is studied. For this, the influence of various solvents (chloroform, dimethylsulfoxide, water) and fluence variation (250–450 mJ/cm²) on the morphological, roughness, wettability, and physico–chemical characteristics of the coatings are evaluated by atomic force microscopy, scanning electron microscopy, contact angle measurements, Fourier-transform-IR spectroscopy, and X-ray photoelectron spectroscopy. Coatings obtained by the spin coating method are used for reference. No significant alteration in the chemistry of the surfaces is observed for the coatings obtained by both methods. All p(NIPAM-BA) coatings show hydrophilic character, with the exception of those obtained with chloroform at 250 mJ/cm². The surface morphology is shown to depend on both solvent type and laser fluence and it ranges from smooth surfaces to rough and porous ones. Physico–chemical and biological analysis reveal that the MAPLE deposition method with fluences of 350–450 mJ/cm² when using DMSO solvent is more appropriate for bioengineering applications due to the surface characteristics (i.e., pore presence) and to the good compatibility with normal cells and cytotoxicity against melanoma cells.     

Free-radical scavenging capacity and reducing power of wild edible mushrooms from northeast Portugal: Individual cap and stipe activity

The antioxidant properties of two wild edible mushroom species from the northeast of Portugal, Lactarius deliciosus (L.) Gray and Tricholoma portentosum (Fr.) Quél., were evaluated. Methanolic extracts from the entire mushroom, the cap and the stipe, separately, were screened for their reducing power and free radical scavenging capacity by chemical assays. The total phenolic content was determined, in order to assess its effect on the extract’s antioxidant activity. Both two species showed antioxidant potential; but L. deliciosus proved to be more active. The portion of the mushroom used had an influence on the results obtained, with the cap methanolic extracts exhibiting the greatest antioxidant effect.