2,372 research outputs found

    Understanding the Absorption of Fluorinated Gases in Fluorinated Ionic Liquids for Recovering Purposes Using Soft-SAFT

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    2020.00835.CEEIND 2021.01432.CEECIND RC2-2019-007It is proven that fluorinated gases (F-gases) have a vast impact on climate change due to their high global warming potential. Hence, it is imperative to search for new molecules to replace them in current applications, as well as technologies to capture, recover, and recycle F-gases to avoid their emissions to the atmosphere. One of the attractive technologies for this purpose is to absorb them in fluorinated ionic liquids (FILs), given their solubilization power. However, the complexity of FILs and the time-consuming experimental methodologies to fully characterize them hinder their prompt usage in this urgent field. In this work, the soft-Statistical Associating Fluid Theory (soft-SAFT) Equation of State is used as a tool to investigate the solubility of six different F-gases (R-32, R-125, R-134a, R-14, R-116, R-218) in five FILs ([C2C1Im][C4F9SO3], [C2C1Im][C4F9CO2], [C2C1py][C4F9SO3], [C2(C6F13)C1Im][N(CF3SO2)2], and [C2(C6F13)C1Im][N(C2F5SO2)2]). The robustness of the soft-SAFT approach allowed the establishment of new FIL models in a simple and fast way, and the calculation of F-gases solubility in them, in excellent agreement with existing experimental data. Once the models were assessed, a systematic study was performed regarding the structural features of FILs favoring their performance to absorb F-gases by using the soft-SAFT approach as a screening tool. It has been obtained that the solubility is favored by the presence of a perfluoroalkyl chain in the imidazolium cation, together with a bulkier anion. In all cases, [C2(C6F13)C1Im][N(C2F5SO2)2] shows a superior solubility of F-gases than the [C2(C6F13)C1Im][N(CF3SO2)2], also indicating that the addition of one carbon to the two anionic symmetric fluorinated chains contributes to the gas-philicity of the FILs. This work proves the relevance of using the soft-SAFT framework to obtain insights into the behavior of such complex systems and key trends, even when experimental data are scarce, as a step forward in assessing systems for separating and recovering F-gases.publishersversioninpres

    Viral hepatitis and the immunological response: a review

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    Introduction: In Brazil, viral hepatitis is infectious disease of compulsory notification and is considered a serious public health problem. Infections with A, B, C, D or E viruses trigger the activation of immune system molecules and cells at the level of innate and acquired immunity. Objective: The present study aimed to review the knowledge about viral hepatitis and the immune system's performance against these infections. Methods: This is a literature overview from academic books and scientific articles available in the Scientific Electronic Library Online, US National Library of Medicine National Institutes of Health and Google Scholar databases. Having as key words hepatitis A, hepatitis B, hepatitis C, hepatitis D, hepatitis E and immune system. The relevant articles corresponding to the period between 1974 and 2017 were selected. Development: Viral hepatitis is characterized by inflammation in liver cells caused by groups of viruses that have hepatotropism in common. The diagnosis is made through serological methods and molecular biology techniques. The approach of the immune system in relation to the combat of this infection follows same particularities. Conclusion: This review demonstrated that the determination of the etiologic agent is essential for the conduct to be taken with the infected individual. Moreover, the immune system is directed related to the viruses elimination, presenting some particularities. In addition, this review highlights that the vaccination is the main responsible for reducing people infected by viruses A and B

    Functionalization of fluorinated ionic liquids: A combined experimental-theoretical study

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    FCT/MCTES (Portugal), through: grant SFRH/BD/130965/2017 (M.LF.); Investigador FCT 2014 (IF/00190/2014 to A.B.P. and IF/00210/2014 to J.M.M.A.); projects PTDC/EQU-EQU/29737/2017, PTDC/QEQ-FTT/3289/2014 and IF/00210/2014/CP1244/CT0003. Associate Laboratory for Green Chemistry-LAQV, financed by national funds from FCT/MCTES (UID/QUI/50006/2019). projects 2018-LC-01 and 2019-URL-IR1rQ-011, from Obra Social "la Caixa" and by Khalifa University through project RCII-2018-0024.We present new experimental and modelling data concerning imidazolium based-FILs synthesized with a hydroxyl group in the end of the cationic hydrogenated side chain and compared them with the analogous non-functionalized FILs in order to verify their suitability in the biomedical field. The thermophysical and thermodynamic properties of the neat compounds and the self-aggregation behaviour of FILs in aqueous solutions were measured and compared with theoretical results from the soft-SAFT equation of state, in good agreement with each other. Results showed that the presence of the hydroxyl group increases the density and viscosity of pure compounds and aqueous mixtures, whereas the thermal stability, melting, free volume, ionicity and self-aggregation behaviour decrease. These properties are improved with respect to the conventional perfluorosurfactants for the desired application, due to the full miscibility in water and the promising improved biocompatibility.authorsversionpublishe

    Antibacterial potential of northeastern Portugal wild plant extracts and respective phenolic compounds

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    The present work aims to assess the antibacterial potential of phenolic extracts, recovered from plants obtained on the North East of Portugal, and of their phenolic compounds (ellagic, caffeic, and gallic acids, quercetin, kaempferol, and rutin), against bacteria commonly found on skin infections. The disk diffusion and the susceptibility assays were used to identify the most active extracts and phenolic compounds. The effect of selected phenolic compounds on animal cells was assessed by determination of cellular metabolic activity. Gallic acid had a higher activity, against gram-positive (S. epidermidis and S. aureus) and gram-negative bacteria (K. pneumoniae) at lower concentrations, than the other compounds. The caffeic acid, also, showed good antibacterial activity against the 3 bacteria used. The gallic acid was effective against the 3 bacteria without causing harm to the animal cells. Gallic and caffeic acid showed a promising applicability as antibacterial agents for the treatment of infected wounds.The authors thank the Foundation for Science and Technology (Portugal) for financial support by the E. Pinho grant (SFRH/BD/62665/2009) and L. Barros grant (SFRH/BPD/4609/2000), and by the projects PEst-OE/EQB/LA0023/2013, PEst-C/CTM/UI0264/2011, and PEst-OE/EQB/LA0023/2013. Also, the authors acknowledge the financial support from FEDER through Programa Operacional Factores de Competitividade-COMPETE and to COMPETE/QREN/EU (CIMO strategic project 19 PEst-OE/AGR/UI0690/2011), and through the Project "BioHealth-Biotechnology and Bioengineering approaches to improve health quality", Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDER. The authors also acknowledge the project "Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB", Ref. FCOMP-01-0124-FEDER-027462

    Toxoplasma gondii infection, congenital toxoplasmosis, toxoplasmic retinochoroiditis and neurotoxoplasmosis: an overview

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    Introduction: The toxoplasmosis disease resulting from Toxoplasma gondii infection can manifest itself in many ways, however, congenital, ocular and cerebral forms require greater care. The infection by this protozoan is directly related to environmental and economic factors of the region. Objective: The present study, through a review in the literature, aimed to reinforce the knowledge about the infection caused by Toxoplasma gondii and its main clinical manifestations. Methods: This is a literature overview from academic books and scientific articles available in the Scientific Electronic Library Online, US National Library of Medicine National Institutes of Health and Google Scholar databases. To search the publications, the following descriptors were used: Toxoplasma gondii, toxoplasmosis, congenital toxoplasmosis, ocular toxoplasmosis and cerebral toxoplasmosis. The most relevant articles corresponding to the period from 2000 to 2017 were selected. Development: Toxoplasmosis may be of congenital or acquired origin after birth. The congenital form occurs during the embryonic/fetal life and through the passage of Toxoplasma gondii through the transplacental route. Ocular disease is common in both congenital and acquired infections and is closely associated with the presence of neurotoxoplasmosis in AIDS patients. Conclusion: Thus, immunocompromised patients and immunosuppressed patients are considered to be risk groups for Toxoplasma gondii infection

    Brazilian Version of the Foot Health Status Questionnaire (FHSQ-Br): Cross-Cultural Adaptation and Evaluation of Measurement Properties

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    OBJECTIVE: To conduct a cross-cultural adaptation of the Foot Health Status Questionnaire into Brazilian-Portuguese and to assess its measurement properties. INTRODUCTION: This instrument is an outcome measure with 10 domains with scores ranging from 0-100, worst to best, respectively. The translated instrument will improve the examinations and foot care of rheumatoid arthritis patients. METHODS: The questions were translated, back-translated, evaluated by a multidisciplinary committee and pre-tested (n = 40 rheumatoid arthritis subjects). The new version was submitted to a field test (n = 65) to evaluate measurement properties such as test-retest reliability, internal consistency and construct validity. The Health Assessment Questionnaire, Numeric Rating Scale for foot pain and Sharp/van der Heijde scores for foot X-rays were used to test the construct validity. RESULTS: The cross-cultural adaptation was completed with minor wording adaptations from the original instrument. The evaluation of measurement properties showed high reliability with low variation coefficients between interviews. The a-Cronbach coefficients varied from 0.468 to 0.855, while correlation to the Health Assessment Questionnaire and Numeric Rating Scale was statistically significant for five out of eight domains. DISCUSSION: Intra- and inter-observer correlations showed high reliability. Internal consistency coefficients were high for all domains, revealing higher values for less subjective domains. As for construct validity, each domain revealed correlations with a specific group of parameters according to what the domains intended to measure. CONCLUSION: The FHSQ was cross-culturally adapted, generating a reliable, consistent, and valid instrument that is useful for evaluating foot health in patients with rheumatoid arthritis

    Biopsia do cório fetal em cães

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    With the great development of the gestational studies in all of the species, we noticed the necessity of adaptations of these techniques for prenatal diagnosis in dogs. Based on this, we studied the feasibility of chorion biopsy guided by ultrasound. Our results demonstrated accuracy on the sex determination being 2 males and 12 females, as well as it would be possible to identify chromosome alteration due to the quality of samplings. Sex determination was accomplished with the identification of Y gene chromosomes in PCR technique. After the collection, fragments were prepared for light microscopy studies and revealed fetal chorion tissue, blood colloid and erythrocyte. In the whole material we found hemosiderin impregnations due to the hemolysis and to the residue of blood of the placental marginal hematomes. The submitted female dogs to this technique demonstrated normal puppy births without death.Com o grande desenvolvimento dos estudos gestacionais em todas as espécies, percebemos a necessidade de adaptarmos técnicas para diagnóstico pré-natal para cães. Assim, buscamos bases nas técnicas já existentes empregadas em humanos, e através destas, conseguimos estabelecer um método para coleta em cães, utilizando PCR para garantirmos a integridade das amostras. O procedimento foi realizado através de punção da cinta placentária com agulha de biopsia guiada por ultra-som. De todas as 14 amostras coletadas, duas apresentaram-se positivas para o cromossomo Y, presente apenas em machos, confirmando assim a viabilidade das amostras demonstrando com isso que através desta técnica podemos coletar material fetal para diagnóstico de alterações gênicas ou cromossômicas presentes nos cães antes mesmo destes virem a termo. A microscopia de material revelou fragmentos de cório fetal, colóide sangüíneo e eritrócitos. Em todo o material encontramos impregnações de hemosiderina devido à hemólise e ao resíduo de sangue dos hematomas marginais placentários. As cadelas submetidas a esta técnica tiveram partos normais sem óbito de nenhum filhote.FAPES

    Aspectos Morfológicos do cordão umbilical de búfalos (Bubalus bubalis)

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    Buffalo is an important livestock resource, with a great participation in agricultural systems, providing milk, meat, and work power. Umbilical cord is responsible for maternal-fetal nutrients exchange during pregnancy, and its alterations can compromise the fetal development. We investigated ten pregnant uteruses collected from cross-bread buffaloes in different stages of gestation. Pregnancy and fetal age was determined by measuring the apex sacral length and development period was calculated by previously published formula. Umbilical cords were measured for length determination. Umbilical cord vascular net and anastomosis were observed by injection of Neoprene latex. Histological sections of the umbilical cord were studied after stain with HE, picrossirius, toluidine blue, orceine, and PAS reaction. Buffaloes' umbilical cord was formed by two central arteries, an allantois duct and two peripheral veins. The artery wall was composed by large quantity of collagen, elastic fibers, fibroblasts and large number of vasa vasorum. The allantois duct was located between the arteries and presented a great number of small nourishing vessels. Small nourishing vessels should be carefully considered to avoid to be mistaken to the arterials and veins vasa vasorum. Medium length of umbilical cord from buffalos was 11.8cm (minimum of 6.8cm and maximum of 17.4cm).Búfalo é uma importante fonte de recurso nos rebanhos animais, apresentando uma grande participação na agropecuária, provendo leite, carne e força de trabalho. O Cordão umbilical é responsável pela troca de nutrientes materno-fetais durante a gestação, e suas alterações podem comprometer o desenvolvimento fetal. Nós investigamos dez úteros gravídicos de búfalos de raças cruzadas em fases diferentes de gestação. O período de gestação e a idade fetal foram determinados pelo comprimento ápice sacral, aplicando fórmulas previamente estabelecidas. Posteriormente mediu-se o comprimento do cordão umbilical. A rede vascular do cordão umbilical e anastomoses foram observadas por injeção ou látex de neoprene. O cordão umbilical foi estudado a partir de cortes histológicos, corados por HE, picrossirius, azul de Toluidina, orceína e reação histoquímica de PAS. O cordão umbilical de búfalos é formado por duas artérias centrais, ducto alantóide e duas veias periféricas e apresentam forma de ampulheta. A parede da artéria umbilical é composta por grande quantidade de fibras colágenas e elásticas, fibroblastos e um grande número de vasa vasorum. O ducto alantóide fica alocado entre as artérias e apresenta um grande número de pequenos vasos nutritivos. Os vasos nutritivos devem ser cuidadosamente identificados para evitar-se confundi-los com vasa vasorum. O comprimento médio do cabo de cordão umbilical dos búfalos era 11.8cm (mínimo de 6.8cm e máximo de 17.4cm)

    Phenotypic and immunohistochemical characterization of sarcoglycanopathies

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    INTRODUCTION: Limb-girdle muscular dystrophy presents with heterogeneous clinical and molecular features. The primary characteristic of this disorder is proximal muscular weakness with variable age of onset, speed of progression, and intensity of symptoms. Sarcoglycanopathies, which are a subgroup of the limb-girdle muscular dystrophies, are caused by mutations in sarcoglycan genes. Mutations in these genes cause secondary deficiencies in other proteins, due to the instability of the dystrophin-glycoprotein complex. Therefore, determining the etiology of a given sarcoglycanopathy requires costly and occasionally inaccessible molecular methods. OBJECTIVE: The aim of this study was to identify phenotypic differences among limb-girdle muscular dystrophy patients who were grouped according to the immunohistochemical phenotypes for the four sarcoglycans. METHODS: To identify phenotypic differences among patients with different types of sarcoglycanopathies, a questionnaire was used and the muscle strength and range of motion of nine joints in 45 patients recruited from the Department of Neurology - HC-FMUSP (Clinics Hospital of the Faculty of Medicine of the University of São Paulo) were evaluated. The findings obtained from these analyses were compared with the results of the immunohistochemical findings. RESULTS: The patients were divided into the following groups based on the immunohistochemical findings: a-sarcoglycanopathies (16 patients), b-sarcoglycanopathies (1 patient), y-sarcoglycanopathies (5 patients), and nonsarcoglycanopathies (23 patients). The muscle strength analysis revealed significant differences for both upper and lower limb muscles, particularly the shoulder and hip muscles, as expected. No pattern of joint contractures was found among the four groups analyzed, even within the same family. However, a high frequency of tiptoe gait was observed in patients with a-sarcoglycanopathies, while calf pseudo-hypertrophy was most common in patients with non-sarcoglycanopathies. The a-sarcoglycanopathy patients presented with more severe muscle weakness than did y-sarcoglycanopathy patients. CONCLUSION: The clinical differences observed in this study, which were associated with the immunohistochemical findings, may help to prioritize the mutational investigation of sarcoglycan genes.CNP

    Understanding the phase and solvation behavior of fluorinated ionic liquids

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    the contract of Individual Call to Scientific Employment Stimulus 2021.01432.CEECIND (A.B.P.) Additional partial support has been provided by Khalifa University of Science and Technology through project RC2-2019-007. Publisher Copyright: © 2022 The AuthorsFluorinated ionic liquids (FILs) are defined as molecules having fluorinated tags equal to or longer than 4 carbon atoms in the anion and/or cation structures. They present nanosegregated domains making them 3-in-1 solvents with exceptional properties, including an attractive solubility power. This work is an important contribution towards understanding the current research on the phase behavior of FILs, which may be used as task-specific materials for industrial applications. An overview of the main works published in the last two decades is presented, concerning gas solubility in FILs, the application of membranes to improve the gas absorption in FILs, and the use of modeling approaches to ease the application of FILs in gas capture and separation processes, with emphasis on the relationship between the structural properties and their performance. Contributions concerning the liquid-liquid and solid-liquid equilibria behavior of FILs, including the liquid-liquid equilibria (LLE) of FILs in water and perfluoroalkanes, and the solid-liquid equilibria (SLE) of solid FILs in water and mixtures of FILs are also presented. Regarding the absorption of gases in FILs, a careful analysis of the published works reveals that: (1) an optimal density of fluorine atoms in FILs structure is required to positively impact the absorption of different gases, (2) the functionalization of membranes can be also a useful method to improve the performance in separation processes, and (3) modeling tools can ease the screening of the features that promote the absorption of gases by FILs. The study of FILs LLE showed a rich phase behavior with water and perfluoroalkanes and the enhanced surfactant power of FILs, which is highly dependent on the length of the hydrogenated and fluorinated side chains. Finally, studying the SLE of FILs mixtures allowed the formation of deep eutectic systems that enlarges the applicability of FILs.publishersversionpublishe
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