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1.
Food Microbiol ; 105: 104031, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35473969

RESUMO

A new nonthermal food pasteurization approach is here presented for the first time, proposed to be called low-pressure long-time (LPLT) pasteurization or moderate pressure pasteurization (MPP) by hyperbaric inactivation (HI). To test this novel pasteurization process on raw milk, MPP by HI was carried out at three different pressure levels (150, 200 and 250 MPa), over 24 h, at naturally variable uncontrolled room temperature (≈20 °C) and compared with high pressure processing (HPP) at 600 MPa (one cycle for 90 s and a second cycle of 120 s) followed by storage under refrigeration for 21 days. Based on the results obtained, MPP at 250 MPa over 24 h caused higher microbial inactivation on total aerobic mesophiles (TAM), lactic acid bacteria (LAB) and Enterobacteriaceae (ENT) (of at least 2.2, 1.7 and 1.3 log CFU/mL, respectively) than HPP (1.1, 1.0 and 1.2 log CFU/mL, for the same microorganisms). Moreover, MPP showed a clear reduction of inoculated microorganisms to below the detection limit, in only 16 h for all pressures with reductions of at least 5.7, 5.4 and 5.5 for Listeria innocua, Salmonella senftenberg, and Escherichia coli, respectively. Additionally, during preservation under refrigeration, MPP samples (200 MPa and 250 MPa), maintained lower TAM/LAB/ENT compared to HPP, being the counts below the quantification/detection limit for at least 21 days for MPP by HI. MPP (200 MPa and 250 MPa) resulted also in counts below the detection limit for the inoculated microorganisms up to at least 21 days under refrigeration. The results of MPP by HI are very promising as a new nonthermal food pasteurization, since over 5 log reduction of vegetative bacteria were achieved, with counts maintained below the quantification/detection limit for at least 21 days under refrigeration.


Assuntos
Lactobacillales , Pasteurização , Animais , Microbiologia de Alimentos , Leite/microbiologia , Refrigeração , Temperatura
2.
Health Promot Int ; 37(2)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-34279624

RESUMO

In Brazil, any advertising strategies that take advantage of the child's judgment or induce consumers to make harmful health choices are considered abusive. However, the efficacy of restrictions on their use on television (TV) food advertising remains poorly understood. This study analysed the extent and nature of abusive techniques according to national regulations and patterns in their use in food-related ads. Cross-sectional studyrecorded the programming of the three most popular TV channels (6 am-12 am), during eight non-consecutive days, in April 2018. Data collection was based on the INFORMAS protocol and two national regulations. Descriptive analyses were used to describe the types of food ads and abusive techniques used in ultra-processed products (UPP) ads. Principal component analysis was applied to identify patterns of abusive marketing techniques and to relate them to specific food groups. More than 90% of food ads included at least one UPP. Overall, 10.1% of UPP ads targeted children and 57.7% used some kind of abusive technique directed to children and adolescents. Most ads contained messages inducing harmful health choices did not present adequate and clear information about the product and contained more than one type of abusive technique. Four out of five patterns in the use of abusive techniques in UPP ads were specifically directed to children, and fast-food meals were associated with three out of five patterns. The high abusiveness of food advertising in UPP ads should be considered a public health concern given their impact on children's food choices and health.


Assuntos
Publicidade , Televisão , Adolescente , Brasil , Criança , Estudos Transversais , Fast Foods , Alimentos , Indústria Alimentícia , Humanos
3.
Regul Toxicol Pharmacol ; 106: 105-110, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31028798

RESUMO

Compared to oral toxicity tests, dermal toxicity tests offer little or no additional scientific information or public health protection for agrochemical-formulated products (US EPA, 2016). Based on that, a retrospective analysis of the results of acute oral and dermal LD50 studies of agrochemical products registered in Brazil was carried out by the Technical Group on Toxicological Risk Assessment (GT-ART) of the Brazilian Crop Protection Association (ANDEF). The data were obtained from 6 agrochemical industries that are associated to ANDEF, following these considerations: only rat studies were selected; only paired studies were chosen; only studies performed with top doses ≥2,000 mg/kg were selected; biological products were excluded. The dataset includes 342 formulated products in 21 formulation types. Among these 342 formulated products, 228 have a single active ingredient, 107 have 2 and 7 have 3 or more. The comparison of acute oral to dermal toxicity studies of agrochemical-formulated products registered in Brazil corroborates the United States Environmental Protection Agency (US EPA) conclusion on waiving acute dermal toxicity tests, which will result in avoiding unnecessary use of time and resources, data generation costs and animal testing.


Assuntos
Agroquímicos/toxicidade , Tomada de Decisões , Pele/efeitos dos fármacos , Testes de Toxicidade Aguda , Administração Cutânea , Administração Oral , Agroquímicos/administração & dosagem , Animais , Brasil , Relação Dose-Resposta a Droga , Humanos , Ratos , Medição de Risco , Estados Unidos , United States Environmental Protection Agency
4.
Foodborne Pathog Dis ; 13(1): 36-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26575358

RESUMO

The impact of extended-spectrum ß-lactamases (ESBLs) and plasmid-mediated AmpC ß-lactamases (PMAßs) of animal origin constitutes a public health concern. In this study, 179 Escherichia coli from food animals and products were analyzed, among which, 15 cephalosporin-resistant isolates harboring ESBL (CTX-M-1 [n = 8], CTX-M-14 [n = 1], SHV-12 [n = 2]) or PMAß [CMY-2, n = 5]) were identified in poultry and swine, from different farms of distinct regions of Portugal. The multiple sequence-type IncI1-driven spread of ESBLs and PMAßs, flanked by widely disseminated mobile elements, was guaranteed by ST26/IncI1-harboring blaSHV-12, ST12/IncI1-harboring blaCMY-2, ST3 and ST38/IncI1-harboring blaCTX-M-1, and ST1/IncI1-harboring blaCTX-M-14. An IS10-disrupted In2-4, presenting a new attI2 recombination site, was also detected in a SHV-12/CTX-M-1-harboring isolate. This study highlights the fact that animals may act as persistent sources of ESBL- and PMAß-harboring plasmids genes that might be transferred to humans through direct contact or via the food chain.


Assuntos
Proteínas de Bactérias/genética , Infecções por Escherichia coli/microbiologia , Escherichia coli/genética , Doenças Transmitidas por Alimentos/microbiologia , Integrons/genética , Aves Domésticas/microbiologia , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Infecções por Escherichia coli/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Plasmídeos/genética , Portugal/epidemiologia , Suínos
5.
Bioengineering (Basel) ; 11(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38391615

RESUMO

Whiplash injuries, mainly located in the neck, are one of the most common injuries resulting from road collisions. These injuries can be particularly challenging to detect, compromising the ability to monitor patients adequately. This work presents the development and validation of a computationally efficient model, called Efficient Neck Model-2D (ENM-2D), capable of simulating the whiplash injury mechanism. ENM-2D is a planar multibody model consisting of several bodies that model the head and neck with the same mass and inertia properties of a male occupant model in the 50th percentile. The damping and non-linear spring parameters of the kinematic joints were identified through a multiobjective optimization process, solved sequentially. The TNO-Human Body Model (TNO-HBM), a validated occupant model for rear impact, was simulated, and its responses were used as a reference for validation purposes. The root mean square (RMS) of the deviations of angular positions of the bodies were used as objective functions, starting from the bottom vertebra to the top, and ending in the head. The sequence was repeated until it converged, ending the optimization process. The identified ENM-2D model could simulate the whiplash injury mechanism kinematics and accurately determine the injury criteria associated with head and neck injuries. It had a relative deviation of 8.3% for the head injury criteria and was 12.5 times faster than the reference model.

6.
Ageing Res Rev ; 95: 102204, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38272265

RESUMO

The pursuit for the fountain of youth has long been a fascination amongst scientists and humanity. Ageing is broadly characterized by a cellular decline with increased susceptibility to age-related diseases, being intimately associated with epigenetic modifications. Recently, reprogramming-induced rejuvenation strategies have begun to greatly alter longevity research not only to tackle age-related defects but also to possibly reverse the cellular ageing process. Hence, in this review, we highlight the major epigenetic changes during ageing and the state-of-art of the current emerging epigenetic reprogramming strategies leveraging on transcription factors. Notably, partial reprogramming enables the resetting of the ageing clock without erasing cellular identity. Promising chemical-based rejuvenation strategies harnessing small molecules, including DNA methyltransferase and histone deacetylase inhibitors are also discussed. Moreover, in parallel to longevity interventions, the foundations of epigenetic clocks for accurate ageing assessment and evaluation of reprogramming approaches are briefly presented. Going further, with such scientific breakthroughs, we are witnessing a rise in the longevity biotech industry aiming to extend the health span and ideally achieve human rejuvenation one day. In this context, we overview the main scenarios proposed for the future of the socio-economic and ethical challenges associated with such an emerging field. Ultimately, this review aims to inspire future research on interventions that promote healthy ageing for all.


Assuntos
Metilação de DNA , Longevidade , Humanos , Adolescente , Longevidade/genética , Envelhecimento/genética , Senescência Celular/genética , Epigênese Genética , Reprogramação Celular/genética
7.
Vasc Endovascular Surg ; 57(5): 513-519, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36710000

RESUMO

Primary aortic mural thrombus (PAMT) is defined as a thrombus attached to the aortic wall in the absence of any atherosclerotic or aneurysmal disease in the aorta and a cardiac source of embolus. There is no consensus on the ideal treatment of PAMT. There are a few reports of thromboaspiration of aortic thrombus in literature. The objective of this article is to report a new endovascular approach of abdominal aortic mural thrombus. The use of Penumbra Thromboaspiration System is a feasible procedure to treat abdominal aortic thrombus and may be an option for patients unsuitable for open repair or conservative treatment.


Assuntos
Embolia , Procedimentos Endovasculares , Tromboembolia , Trombose , Humanos , Resultado do Tratamento , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/cirurgia , Embolia/terapia , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/cirurgia
8.
RMD Open ; 9(3)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37652558

RESUMO

OBJECTIVES: The main goal of this study was to characterise the frequency and phenotype of B, T follicular helper (Tfh) and T follicular regulatory (Tfr) cells in peripheral blood and the cytokine environment present in circulation in children with extended oligoarticular juvenile idiopathic arthritis (extended oligo JIA) and polyarticular JIA (poly JIA) when compared with healthy controls, children with persistent oligoarticular JIA (persistent oligo JIA) and adult JIA patients. METHODS: Blood samples were collected from 105 JIA patients (children and adults) and 50 age-matched healthy individuals. The frequency and phenotype of B, Tfh and Tfr cells were evaluated by flow cytometry. Serum levels of APRIL, BAFF, IL-1ß, IL-2, IL-4, IL-6, IL-10, IL-17A, IL-21, IL-22, IFN-γ, PD-1, PD-L1, sCD40L, CXCL13 and TNF were measured by multiplex bead-based immunoassay and/or ELISA in all groups included. RESULTS: The frequency of B, Tfh and Tfr cells was similar between JIA patients and controls. Children with extended oligo JIA and poly JIA, but not persistent oligo JIA, had significantly lower frequencies of plasmablasts, regulatory T cells and higher levels of Th17-like Tfh cells in circulation when compared with controls. Furthermore, APRIL, BAFF, IL-6 and IL-17A serum levels were significantly higher in paediatric extended oligo JIA and poly JIA patients when compared with controls. These immunological alterations were not found in adult JIA patients in comparison to controls. CONCLUSIONS: Our results suggest a potential role and/or activation profile of B and Th17-like Tfh cells in the pathogenesis of extended oligo JIA and poly JIA, but not persistent oligo JIA.


Assuntos
Artrite Juvenil , Interleucina-17 , Humanos , Criança , Interleucina-6 , Subpopulações de Linfócitos T , Citocinas
9.
Biochem Biophys Res Commun ; 423(1): 170-5, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22640734

RESUMO

Obesity consists in fat accumulation leading to increase in adipose cells number and size. Adipocyte membrane biophysical properties are critical to maintain cellular viability in metabolically healthy obesity. This study investigated the effect of the genetic background and dietary protein restriction on fat tissue lipid composition, adipocyte membrane fluidity and water permeability using the pig as experimental model. Twenty-four male pigs from distinct genotypes, lean and obese, were fed on normal and reduced protein diets within a 2 × 2 factorial arrangement (two genotypes and two diets). Backfat thickness was twofold higher in obese than in lean pigs but unrelated to dietary protein level. In contrast, total fatty acids in the subcutaneous adipose tissue were dependent on both breed and diet, with increased lipid content promoted by the fatty genotype and by the restriction of dietary protein. Adipose membranes isolated from obese pig's subcutaneous fat tissue showed higher permeability to water, in line with an increased fluidity. Moreover, the reduced content of dietary protein influenced positively the fluidity of adipose membranes. Neither genotype nor diet affected total cholesterol concentration in the adipose membranes. Membrane-saturated fatty acids' content was influenced by genotype, while membrane-polyunsaturated fatty acids, particularly from the n-6 family, was influenced by diet. The ratio of oleic (18:1c9)/linoleic (18:2n-6) acids was positively correlated with membrane fluidity. All together, these findings reinforce the genetic background as a determinant player on adipose membrane biophysical properties and point to the dietary protein level as an important factor for subcutaneous lipid deposition as well as for regulation of membrane function, factors that may have impact on human obesity and metabolic syndrome.


Assuntos
Tecido Adiposo/metabolismo , Membrana Celular/metabolismo , Dieta , Proteínas Alimentares/administração & dosagem , Ácidos Graxos/metabolismo , Fluidez de Membrana , Obesidade/metabolismo , Magreza/metabolismo , Adipócitos/química , Adipócitos/metabolismo , Animais , Membrana Celular/química , Permeabilidade da Membrana Celular , Ácidos Graxos/análise , Masculino , Obesidade/genética , Suínos , Magreza/genética
10.
Antibiotics (Basel) ; 11(2)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35203814

RESUMO

The major concern regarding the bacteriophage (or phage) therapy approach is the regrowth of bacteria after treatment, a consequence of the emergence of phage-resistant mutants. However, this limitation can be overcome by combining different therapies. In this study, the potential of combining phage phT4A with pressure storage (HS) to enhance the control of Escherichia coli and bacterial regrowth after treatment was evaluated. For that, the combining effect of phage phT4A and HS was studied and compared with storage at atmospheric pressure (AP) under refrigeration (4 °C, RF) and room temperature (RT). Initially, the effect of high hydrostatic pressure (200, 300 and 400 MPa) and HS (75 MPa), as well as refrigeration in phage phT4A viability, was determined. However, a considerable phage inactivation was verified at 200 MPa and so only HS at 75 MPa was further studied for combined treatment. The combined treatment with phage phT4A and HS was more efficient (reduction of 2.5 log CFU/mL after 7 days of storage) than phage phT4A (E. coli concentration was similar to that of the bacterial control after 7 days of storage) and HS (reduction of 1.8 log CFU/mL after 7 days of storage) applied individually. The combination of phage phT4A with refrigerated storage did not decrease E. coli levels. However, both the combination of phage with HS and the treatment with HS at 75 MPa effectively reduced E. coli concentration and prevented its regrowth. Phage phT4A viability was slightly affected during HS; however, the efficiency of the combined treatment phage-HS was not compromised. Further studies are needed to validate these findings in food products.

11.
Food Chem ; 384: 132236, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35240572

RESUMO

Microalgae, as a photosynthetic autotrophic organism, contain a variety of bioactive compounds, including lipids, proteins, polysaccharides, which have been applied in food, medicine, and fuel industries, among others. Microalgae are considered a good source of marine lipids due to their high content in unsaturated fatty acid (UFA) and can be used as a supplement/replacement for fish-based oil. The high concentration of docosahexaenoic (DHA) and eicosapentaenoic acids (EPA) in microalgae lipids, results in important physiological functions, such as antibacterial, anti-inflammatory, and immune regulation, being also a prerequisite for its development and application. In this paper, a variety of approaches for the extraction of lipids from microalgae were reviewed, including classical and innovative approaches, being the advantages and disadvantages of these methods emphasized. Further, the effects of microalgae lipids as high value bioactive compounds in human health and their use for several applications are dealt with, aiming using green(er) and effective methods to extract lipids from microalgae, as well as develop and extend their application potential.


Assuntos
Microalgas , Animais , Suplementos Nutricionais , Ácido Eicosapentaenoico/metabolismo , Microalgas/metabolismo
12.
Trends Ecol Evol ; 37(1): 79-94, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563403

RESUMO

Acoustic telemetry (AT) is a rapidly evolving technique used to track the movements of aquatic animals. As the capacity of AT research expands it is important to optimize its relevance to management while still pursuing key ecological questions. A global review of AT literature revealed region-specific research priorities underscoring the breadth of how AT is applied, but collectively demonstrated a lack of management-driven objectives, particularly relating to fisheries, climate change, and protection of species. In addition to the need for more research with direct pertinence to management, AT research should prioritize ongoing efforts to create collaborative opportunities, establish long-term and ecosystem-based monitoring, and utilize technological advancements to bolster aquatic policy and ecological understanding worldwide.


Assuntos
Ecossistema , Pesqueiros , Acústica , Animais , Conservação dos Recursos Naturais/métodos , Telemetria/métodos
13.
Foods ; 10(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34681354

RESUMO

Due to its characteristics, fresh fish is a highly perishable food with a very short shelf-life under refrigeration. Several methods have been introduced to slow down its deterioration, such as by means of oxygen depletion of the food package (vacuum packaging), or by changing the natural atmosphere that is in contact with the fresh fish (modified atmosphere packaging), or by the use of chemicals generally recognized as safe: such compounds can be directly applied (by dipping or spraying) or incorporated into packaging materials and slowly migrate to the product, exerting a hurdle effect against microbial development and lipid oxidation (active packaging). This review aims to cover the most recent advances in chemical-based approaches for fresh fish preservation, applied either singly or in combination. Vacuum packaging, modified atmosphere, and active packaging preservation methodologies are presented, along with the inclusion of chemical additives, such as organic acids and natural extracts, and their combination with icing systems. Advantages and disadvantages of these methodologies and their impact on fresh fish quality and shelf-life are discussed, reaching the conclusion that both are positively influenced overall. Indeed, the contribution of chemical-based strategies for fresh fish preservation is undeniable, and is expected to be a research topic of increasing interest in the future.

14.
Biochem Biophys Res Commun ; 398(2): 199-204, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20599739

RESUMO

Conjugated linoleic acid (CLA) is a dietary fatty acid frequently used as a body fat reducing agent whose effects upon cell membranes and cellular function remain unknown. Obese Zucker rats were fed atherogenic diets containing saturated fats of vegetable or animal origin with or without 1% CLA, as a mixture of cis(c)9,trans(t)11 and t10,c12 isomers. Plasma membrane vesicles obtained from visceral adipose tissue were used to assess the effectiveness of dietary fat and CLA membrane incorporation and its outcome on fluidity and permeability to water and glycerol. A significant decrease in adipose membrane fluidity was correlated with the changes observed in permeability, which seem to be caused by the incorporation of the t10,c12 CLA isomer into membrane phospholipids. These results indicate that CLA supplementation in obese Zucker rats fed saturated and cholesterol rich diets reduces the fluidity and permeability of adipose membranes, therefore not supporting CLA as a body fat reducing agent through membrane fluidification in obese fat consumers.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Linoleicos Conjugados/administração & dosagem , Fluidez de Membrana/efeitos dos fármacos , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Animais , Masculino , Ratos , Ratos Zucker
15.
Macromol Biosci ; 20(11): e2000119, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32597002

RESUMO

Iongels have attracted much attention over the years as ion-conducting soft materials for applications in several technologies including stimuli-responsive drug release and flexible (bio)electronics. Nowadays, iongels with additional functionalities such as electronic conductivity, self-healing, thermo-responsiveness, or biocompatibility are actively being searched for high demanding applications. In this work, a simple and rapid synthetic pathway to prepare elastic and thermoreversible iongels is presented. These iongels are prepared by supramolecular crosslinking between polyphenols biomolecules with a hydroxyl-rich biocompatible polymer such as poly(vinyl alcohol) (PVA) in the presence of ionic liquids. Using this strategy, a variety of iongels are obtained by combining different plant-derived polyphenol compounds (PhC) such as gallic acid, pyrogallol, and tannic acid with imidazolium-based ionic liquids, namely 1-ethyl-3-methylimidazolium dicyanamide and 1-ethyl-3-methylimidazolium bromide. A suite of characterization tools is used to study the structural, morphological, mechanical, rheological, and thermal properties of the supramolecular iongels. These iongels can withstand large deformations (40% under compression) with full recovery, revealing reversible transitions from solid to liquid state between 87 and 125 °C. Finally, the polyphenol-based thermoreversible iongels show appropriated properties for their potential application as printable electrolytes for bioelectronics.


Assuntos
Elasticidade , Géis/química , Fenol/química , Álcool de Polivinil/química , Temperatura , Varredura Diferencial de Calorimetria , Força Compressiva , Ácido Gálico/química , Íons , Polifenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
16.
World Rev Nutr Diet ; 121: 193-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33502380

RESUMO

Legume grains are traditional crops that have been modernized as processed foods and animal protein alternatives in recent years. This modernization has largely been fueled by new technological developments driven by increased consumer demands for plant protein and gluten-free options. However, consumers must be mindful that legumes have other nutritional attributes besides protein that help achieve healthier diets, and recent evidence suggests that consuming 100 g of legume grains per day would promote nutrient-dense diets and could be a target level to harmonize international strategies for recommended daily allowances. The nutritional richness of legumes has been associated with a decrease in numerous disease risk factors and, given their long shelf life, legumes are excellent choices to combat food waste and may have a role to play in countries where cold storage is often a limitation in food preservation. Besides their inclusion in global diets, legumes should be included in sustainable cropping systems. The high number of edible species and cultivars available render them excellent contributors to biodiverse food and feed systems. Legume cultivation allows reducing environmental impacts by means of the ability of legumes to fix atmospheric nitrogen via a symbiosis with nitrogen-fixing bacteria, making them natural fertilizers. Still, despite the well-known health, nutritional, and environmental benefits, legumes are underrepresented in global agri-food systems. Efforts must be made to make legumes more attractive to the farmer, the industry, and ultimately the consumer, and for this proper local, regional, national, and global policy frameworks must be in place. Here, the local scenario of legumes is showcased, and the most relevant push, pull, and enabling capacities required to achieve sustainable diversified agri-food systems with legumes are discussed.


Assuntos
Agricultura/métodos , Agricultura/estatística & dados numéricos , Produtos Agrícolas , Dieta Saudável/métodos , Dieta Saudável/estatística & dados numéricos , Fabaceae , Desenvolvimento Sustentável , Humanos
17.
Membranes (Basel) ; 10(3)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192181

RESUMO

Iongel-based CO2 separation membranes were prepared by fast (< 1 min) UV-initiated polymerization of poly(ethylene glycol) diacrylate (PEGDA) in the presence of different ionic liquids (ILs) with the [C2mim]+ cation and anions such as [TFSI]-, [FSI]-, [C(CN)3]- and [B(CN)4]-. The four ILs were completely miscible with the non-ionic PEGDA network. Transparent and free-standing iongels containing between 60 and 90 %wt of IL were obtained and characterized by diverse techniques (FTIR, TGA, DSC, DMTA, SEM, CO2 solubility and pure gas permeability). The thermal and mechanical stability of the iongels, as well as CO2 solubility, were found to be strictly dependent on the IL content and the anion's nature. The TGA results indicated that the iongels mostly follow the thermal profile of the respective neat ILs. The DMTA analysis revealed that the iongels based on fluorinated anions have higher storage modulus than those of cyano-functionalized anions. Conversely, the PEGDA-C(CN)3 iongels presented the highest CO2 solubility values ranging from 72 to 80 mmol/g. Single CO2 permeabilities of 583 ± 29 Barrer and ideal CO2/N2 selectivities of 66 ± 3 were obtained with the PEGDA-70 C(CN)3 iongel membrane. This work demonstrates that the combination of PEGDA with high contents of the best performing ILs is a promising and simple strategy, opening up new possibilities in the design of high-performance iongel membranes for CO2 separation.

18.
Biochem Biophys Res Commun ; 383(1): 108-12, 2009 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-19341709

RESUMO

Conjugated linoleic acid (CLA) refers to a group of positional and geometrical isomers of linoleic acid in which the double bonds are conjugated. Dietary CLA has been associated with various health benefits although details of its molecular mode of action remain elusive. The effect of CLA supplemented to palm oil-based diets in Wistar rats, as a mixture of both or isolated c9,t11 and t10,c12 isomers, was examined on water and glycerol membrane permeability of kidney proximal tubule. Although water permeability was unaltered, an increase in glycerol permeability was obtained for the group supplemented with CLA mixture, even though the activation energy for glycerol permeation remained high. This effect was correlated with an increased CLA isomeric membrane incorporation for the same dietary group. These results suggest that diet supplementation with CLA mixture, in contrast to its individual isomers, may enhance membrane fluidity subsequently raising kidney glycerol reabsorption.


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Dieta , Glicerol/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Ácidos Linoleicos Conjugados/administração & dosagem , Água/metabolismo , Animais , Isomerismo , Túbulos Renais Proximais/metabolismo , Ácidos Linoleicos Conjugados/química , Ratos , Ratos Wistar
19.
J Mol Histol ; 39(2): 217-25, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18034316

RESUMO

Quiescin Q6/sulfhydryl oxidases (QSOX) are revisited thiol oxidases considered to be involved in the oxidative protein folding, cell cycle control and extracellular matrix remodeling. They contain thioredoxin domains and introduce disulfide bonds into proteins and peptides, with the concomitant hydrogen peroxide formation, likely altering the redox environment. Since it is known that several developmental processes are regulated by the redox state, here we assessed if QSOX could have a role during mouse fetal development. For this purpose, an anti-recombinant mouse QSOX antibody was produced and characterized. In E(13.5), E(16.5) fetal tissues, QSOX immunostaining was confined to mesoderm- and ectoderm-derived tissues, while in P1 neonatal tissues it was slightly extended to some endoderm-derived tissues. QSOX expression, particularly by epithelial tissues, seemed to be developmentally-regulated, increasing with tissue maturation. QSOX was observed in loose connective tissues in all stages analyzed, intra and possibly extracellularly, in agreement with its putative role in oxidative folding and extracellular matrix remodeling. In conclusion, QSOX is expressed in several tissues during mouse development, but preferentially in those derived from mesoderm and ectoderm, suggesting it could be of relevance during developmental processes.


Assuntos
Feto/enzimologia , Oxirredutases/metabolismo , Animais , Animais Recém-Nascidos , Especificidade de Anticorpos , Imuno-Histoquímica , Masculino , Camundongos , Oxirredutases/análise , Oxirredutases/imunologia , Coelhos , Ratos , Ratos Wistar , Distribuição Tecidual
20.
Membranes (Basel) ; 8(4)2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30314326

RESUMO

The efficient separation of gases has industrial, economic, and environmental importance. Here, we report the improvement in gas separation performance of a polyimide-based matrix (Matrimid®5218) filled with a Cu-based metal organic framework [MOF, Cu3(BTC)2] with two different ionic liquids (ILs) confined within the pores. The chosen ILs are commonly used in gas solubilization, 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) and 1-Ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][OTf]), and the incorporation of the [EMIM][BF4]@Cu-BTC and [EMIM][OTf]@Cu-BTC composites in Matrimid®5218 proved to be an efficient strategy to improve the permeability and selectivity toward CO2/N2 and CO2/CH4 mixtures.

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