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CONTEXT: The advancement in the development of second-generation drugs in the field of antihistamines represents a significant milestone in the management of allergic diseases, targeting the effects of histamine. The efficacy of bilastine in treating allergic disorders has sparked interest in investigating its polymorphism, a crucial property that impacts quality, safety, and effectiveness as per regulatory guidelines. This study examines the polymorphism of bilastine, focusing on two crystalline forms labeled as Form I and Form II. Utilizing advanced analytical techniques, the research explores the structural characteristics and molecular interactions within these forms. Geometric parameters, such as bond lengths, bond angles, and torsion angles, are examined to comprehend molecular conformations and crystal packing arrangements. Hydrogen bonding, covalent bonds, and van der Waals forces contribute to the unique supramolecular arrangements in these forms. This study provides a significant contribution to understanding bilastine's polymorphism, offering critical insights to researchers and regulatory bodies to ensure the quality, efficacy, and safety of antihistamine products. METHODS: The molecular conformation of two bilastine forms was obtained through DFT with the exchange-correlation functional M06-2X and the 6-311 + + G(d,p) basis set, and the results were compared with the experimental X-ray. The atomic coordinates were obtained directly from the crystalline structures, and charge transfer was also investigated using frontier molecular orbitals (HOMO and LUMO), and MEP map in order to evaluate the energies associated with charge transfers and regions of high electron affinity. The geometric and topological parameters and intermolecular interactions in the crystals were analyzed using Hirshfeld Surface.
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This study conducts a numerical comparison of the thermal performance of three distinct working fluids (pure water, TiO2, and SiO2 water-based nanofluids) within an evacuated tube solar collector using Computational Fluid Dynamics. The study evaluates thermohydraulic performance alongside global and local entropy generation rates, while considering variations in solar radiation values and inlet mass flow rates. Results indicate that nanofluids demonstrate superior performance under low solar radiation, exhibiting higher outlet temperatures, velocities, thermal efficiency, and exergy efficiency compared to pure water. However, at the higher solar radiation level, the efficiency of SiO2 water-based nanofluid diminishes due to its impact on specific heat. Furthermore, the entropy generation analysis reveals significant reductions with TiO2 water-based nanofluid in all the phenomena considered (up to 79 %). The SiO2 nanofluid performance aligns closely with pure water under high radiation value. This investigation offers valuable insights into the utilization of nanofluids in solar collectors across diverse operating conditions, emphasizing their pivotal role in enhancing overall performance.
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Climate change and the demand for clean energy have challenged scientists worldwide to produce/store more energy to reduce carbon emissions. This work proposes a conductive gel biopolymer electrolyte to support the sustainable development of high-power aqueous supercapacitors. The gel uses saline water and seaweed as sustainable resources. Herein, a biopolymer agar-agar, extracted from red algae, is modified to increase gel viscosity up to 17-fold. This occurs due to alkaline treatment and an increase in the concentration of the agar-agar biopolymer, resulting in a strengthened gel with cohesive superfibres. The thermal degradation and agar modification mechanisms are explored. The electrolyte is applied to manufacture sustainable and flexible supercapacitors with satisfactory energy density (0.764â Wh kg-1 ) and power density (230â W kg-1 ). As an electrolyte, the aqueous gel promotes a long device cycle life (3500â cycles) for 1â A g-1 , showing good transport properties and low cost of acquisition and enabling the supercapacitor to be manufactured outside a glove box. These features decrease the cost of production and favor scale-up. To this end, this work provides eco-friendly electrolytes for the next generation of flexible energy storage devices.
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Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants of considerable public health concern. Polycyclic aromatic hydrocarbons arise from natural and anthropogenic sources and are ubiquitously present in the environment. Several PAHs are highly toxic to humans with associated carcinogenic and mutagenic properties. Further, more severe harmful effects on human- and environmental health have been attributed to the presence of high molecular weight (HMW) PAHs, that is PAHs with molecular mass greater than 300 Da. However, more research has been conducted using low molecular weight (LMW) PAHs). In addition, no HMW PAHs are on the priority pollutants list of the United States Environmental Protection Agency (US EPA), which is limited to only 16 PAHs. However, limited analytical methodologies for separating and determining HMW PAHs and their potential isomers and lack of readily available commercial standards make research with these compounds challenging. Since most of the PAH kinetic data originate from animal studies, our understanding of the effects of PAHs on humans is still minimal. In addition, current knowledge of toxic effects after exposure to PAHs may be underrepresented since most investigations focused on exposure to a single PAH. Currently, information on PAH mixtures is limited. Thus, this review aims to critically assess the current knowledge of PAH chemical properties, their kinetic disposition, and toxicity to humans. Further, future research needs to improve and provide the missing information and minimize PAH exposure to humans.
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Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Animais , Humanos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental/métodos , Corpo Humano , Poluentes Ambientais/toxicidade , Poluentes Ambientais/análise , CarcinógenosRESUMO
Leprosy is a much-feared incapacitating infectious disease caused by Mycobacterium leprae or M lepromatosis, annually affecting roughly 200,000 people worldwide. During host-pathogen interaction, M leprae subverts the immune response, leading to development of disease. Throughout the last few decades, the impact of energy metabolism on the control of intracellular pathogens and leukocytic differentiation has become more evident. Mitochondria play a key role in regulating newly-discovered immune signaling pathways by controlling redox metabolism and the flow of energy besides activating inflammasome, xenophagy, and apoptosis. Likewise, this organelle, whose origin is probably an alphaproteobacterium, directly controls the intracellular pathogens attempting to invade its niche, a feature conquered at the expense of billions of years of coevolution. In the present review, we discuss the role of reduced host cell mitochondrial activity during M leprae infection and the consequential fates of M leprae and host innate immunity. Conceivably, inhibition of mitochondrial energy metabolism emerges as an overlooked and novel mechanism developed by M leprae to evade xenophagy and the host immune response.
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Hanseníase , Mycobacterium leprae , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , MitocôndriasRESUMO
We developed a composite hydrogel based on chitosan and carboxymethyl cellulose with nanometric hydroxyapatite (nHA) as filler (ranging from 0.5 to 5%), by ultrasonic methodology to be used for bone regeneration. The 3D porous-structure of the biocomposite scaffolds were confirmed by Scanning Electron Microscopy and Microtomography analysis. Infrared analysis did not show specific interactions between the organic components of the composite and nHA in the scaffold. The hydrogel properties of the matrices were studied by swelling and mechanical tests, indicating that the scaffold presented a good mechanical behavior. The degradation test demonstrated that the material is slowly degraded, while the addition of nHA slightly influences the degradation of the scaffolds. Biocompatibility studies carried out with bone marrow mesenchymal progenitor cells (BMPC) showed that cell proliferation and alkaline phosphatase activity were increased depending on the matrix nHA content. On the other hand, no cytotoxic effect was observed when RAW264.7 cells were seeded on the scaffolds. Altogether, our results allow us to conclude that these nanobiocomposites are promising candidates to induce bone tissue regeneration.
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Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Carboximetilcelulose Sódica/farmacologia , Quitosana/farmacologia , Durapatita/farmacologia , Animais , Materiais Biocompatíveis/química , Carboximetilcelulose Sódica/análogos & derivados , Linhagem Celular , Quitosana/química , Durapatita/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Polieletrólitos/química , Polieletrólitos/farmacologia , Células RAW 264.7 , Alicerces Teciduais/químicaRESUMO
Zika virus (ZIKV) infection during pregnancy is associated with a spectrum of developmental impairments known as congenital Zika syndrome (CZS). The prevalence of this syndrome varies across ZIKV endemic regions, suggesting that its occurrence could depend on cofactors. Here, we evaluate the relevance of protein malnutrition for the emergence of CZS. Epidemiological data from the ZIKV outbreak in the Americas suggest a relationship between undernutrition and cases of microcephaly. To experimentally examine this relationship, we use immunocompetent pregnant mice, which were subjected to protein malnutrition and infected with a Brazilian ZIKV strain. We found that the combination of protein restriction and ZIKV infection leads to severe alterations of placental structure and embryonic body growth, with offspring displaying a reduction in neurogenesis and postnatal brain size. RNA-seq analysis reveals gene expression deregulation required for brain development in infected low-protein progeny. These results suggest that maternal protein malnutrition increases susceptibility to CZS.
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Desnutrição/complicações , Infecção por Zika virus/congênito , Infecção por Zika virus/complicações , Animais , Animais Recém-Nascidos , Peso Corporal , Encéfalo/enzimologia , Encéfalo/patologia , Brasil/epidemiologia , Dieta com Restrição de Proteínas , Surtos de Doenças , Embrião de Mamíferos/patologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Desnutrição/virologia , Camundongos Endogâmicos C57BL , Microcefalia/complicações , Microcefalia/virologia , Neurogênese , Tamanho do Órgão , Gravidez , Síndrome , Carga Viral , Infecção por Zika virus/virologiaRESUMO
The development of efficient advanced functional materials is highly dependent on properties such as morphology, crystallinity, and surface functionality. In this work, hierarchical flowerlike nanostructures of SrTiO3 have been synthesized by a simple template-free solvothermal method involving poly(vinylpyrrolidone) (PVP). Molecular dynamics simulations supported by structural characterization have shown that PVP preferentially adsorbs on {110} facets, thereby promoting the {100} facet growth. This interaction results in the formation of hierarchical flowerlike nanostructures with assembled nanosheets. The petal morphology is strongly dependent on the presence of PVP, and the piling up of nanosheets, leading to nanocubes, is observed when PVP is removed at high temperatures. This work contributes to a better understanding of how to control the morphological properties of SrTiO3, which is fundamental to the synthesis of perovskite-type materials with tailored properties.
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BACKGROUND: Analyze the long-term sex specific trends in suicide rates for Ecuadorian children, adolescents and young people, as well as to describe the evolution of the male/female ratio between 1990 and 2017. METHOD: Population and mortality data were obtained from the National Institute of Statistics and Censuses of Ecuador. Suicide rates were calculated for each year, age group (10-14, 15-19, 20-24 years) and sex. We used the Joinpoint Regression Program 4.6.0.2 to analyze temporal trends and report annual percent change (APC) by each age group and sex. RESULTS: An average of 313 suicides per year happened in Ecuador between 1990 and 2017, with increases of 480% in young boys and 322 % in girls aged between 10-14, 111% in male adolescents and 57% in young adults, while there was a decrease in adolescent girls (19%) and young adults (37%). The suicide rate increased annually among boys (APC = 5.10%) and girls (2.57%), as well as for male adolescents (3.07%) and young adults (10.42%), while for female adolescents (0.81%, not significant) and young women (1.16%) the trend decreased after reaching a peak around 2006. While up until the beginning of the XXI century young females aged between 10 and 19 years had higher suicide rates, during the last decade men had higher rates across all age groups (between 1.5:1 and 4.3:1 in 2017). CONCLUSIONS: Suicide in the population under 25 years in Ecuador is a major public health issue and increased between 1990 and 2017, particularly among children, and males between 15-24 years. The intersectorial strategy proposed in 2018 in order to reduce suicide is pending further evaluation and interpretation.