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1.
Cogn Emot ; : 1-9, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554265

RESUMEN

Features of threatening cues and the associated context influence the perceived imminence of threat and the defensive responses evoked. To provide additional knowledge about how the directionality of a threat (i.e. directed-towards or away from the viewer) might impact defensive responses in humans, participants were shown pictures of a man carrying a gun (threat) or nonlethal object (neutral) directed-away from or towards the participant. Cardiac and electrodermal responses were collected. Compared to neutral images, threatening images depicting a gun directed-towards the participant induced sustained bradycardia and an increased electrodermal response, interpreted as immobility under attack. This defensive immobility reaction is evoked by high perceived threat and inescapable situations and indicates intense action preparation. Pictures of guns directed-away from the participant induced shorter bradycardia and no significant modulation of the electrodermal response compared to neutral pictures, which might be consistent with the perception of a less threatening situation. The results show that the directionality of threat stimuli is a key factor that prompts different patterns of defensive responses.

2.
Crit Rev Food Sci Nutr ; : 1-20, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36847145

RESUMEN

Consumers' demand for foods with high nutritional value and health benefits has fueled the development of prebiotic foods. In coffee industry, cherries transformation into roasted beans generates a large amount of waste/by-products (pulp/husks, mucilage, parchment, defective beans, silverskin and spent coffee grounds) that usually end up in landfills. The possibility to use coffee by-products as relevant sources of prebiotic ingredients is herein ascertained. As a prelude to this discussion, an overview of pertinent literature on prebiotic action was conducted, including on biotransformation of prebiotics, gut microbiota, and metabolites. Existing research indicates that coffee by-products contain significant levels of dietary fiber and other components that can improve gut health by stimulating beneficial bacteria in the colon, making them excellent candidates for prebiotic ingredients. Oligosaccharides from coffee by-products have lower digestibility than inulin and can be fermented by gut microbiota into functional metabolites, such as short-chain fatty acids. Depending on the concentration, melanoidins and chlorogenic acids may also have prebiotic action. Nevertheless, there is still a lack of in vivo studies to validate such findings in vitro. This review shows how coffee by-products can be interesting for the development of functional foods, contributing to sustainability, circular economy, food security, and health.


Coffee by-product oligosaccharides increase short-chain fatty acid levels.Melanoidins and chlorogenic acids promote the growth of lactobacillus and bifidobacteria.Coffee by-products show prebiotic potential, but further in vivo studies are required.

3.
Phys Chem Chem Phys ; 25(42): 28982-28997, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37859503

RESUMEN

Two-dimensional (2D) materials formed by thin-films of metal oxides that grow on metal supports are commonly used in heterogeneous catalysis and multilayer electronic devices. Despite extensive research on these systems, the effects of charged defects at supported oxides on surface processes are still not clear. In this work, we perform spin-polarized density-functional theory (DFT) calculations to investigate formation and interaction of charged magnesium and oxygen vacancies, and Al dopants on MgO(001)/Ag(001) surface. The results show a sizable interface compressive effect that decreases the metal work function as electrons are added on the MgO surface with a magnesium vacancy. This surface displays a larger formation energy in a water environment (O-rich condition) even with additional Al-doping. Under these conditions, we found that a polar molecule such as CO is more strongly adsorbed on the low-coordination oxygen sites due to a larger contribution of the channeled electronic transport with the silver interface regardless of the surface charge. Therefore, these findings elucidate how surface intrinsic vacancies can influence or contribute to charge transfer, which allows one to explore more specific reactions at different surface topologies for more efficient catalysts for CO2 conversion.

4.
J Environ Manage ; 345: 118908, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37688957

RESUMEN

This work proposes exposure limits for carbon monoxide in the nuclear submarine environment. Linear and non-linear forms of the Coburn-Foster-Kane equation were used to evaluate carbon monoxide exposure for an environment with low oxygen content, different exposure times and crew physical activity levels. We evaluated the 90-day Continuous Exposure Guidance Level, 24-h and 1-h Emergency Exposure Guidance Levels and 10-day and 24-h Submarine Escape Action Levels. The results showed that the concentration of carbon monoxide in the environment must not exceed 9 ppm for the 90-day Continuous Exposure Guidance Level, 35 ppm for the 24-h Emergency Exposure Guidance Level, 90 ppm 1-h Emergency Exposure Guidance Level, 60 ppm for the 10-day Submarine Escape Action Level and 80 ppm for the 24-h Submarine Escape Action Level. Comparing these values with those established by the National Research Council for the United States Navy, the limits proposed by this work are verified to be lower, which may indicate a risk to the health of the crew. They also show the impact of the crew's level of physical activity on the formation of carboxyhemoglobin.


Asunto(s)
Monóxido de Carbono , Carboxihemoglobina , Carboxihemoglobina/análisis , Atmósfera
5.
J Environ Manage ; 345: 118822, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37597369

RESUMEN

The reverse water gas shift (RWGS) reaction converts carbon dioxide (CO2) and hydrogen (H2) to syngas, which is used to produce various high-added-value chemicals. This process has attracted great interest from researchers as a way of mitigating the potential environmental impacts of this greenhouse gas, with emphasis on global warming. This work aims to model and simulate an industrial catalytic reactor using kinetic data for the RWGS reaction. The simulation was carried out in Aspen Plus® v10. The thermodynamic analysis showed that the appropriate conditions for the reaction are feed molar ratio (H2/CO2) of 0.8:1, 750 °C, and 20 bar. The RWGS process proceeds in a multi-tubular fixed bed reactor with 36.26% CO2 conversion and 96.41% CO selectivity, at residence times in the order of 2.7 s. These results are at near-equilibrium CO2 conversion with higher CO selectivity.


Asunto(s)
Dióxido de Carbono , Agua , Hidrógeno , Termodinámica , Simulación por Computador
6.
Molecules ; 28(2)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36677786

RESUMEN

The increasing demand for superfoods has resulted in an increase in chia seeds consumption. The reintroduction of this ancient crop in agriculture is useful to ensure food security since it can grow in high-stress conditions. The current study aimed to characterize chia seeds, cold-pressed oil, and defatted cake (the oil extraction by-product) to improve their value and to meet consumer's expectations (low-fat products). Chia seeds presented a significantly higher energy value than cake (444 vs. 284 kcal/100 g, respectively) due to fat removal (33 vs. 7%). The cake showed higher contents of total minerals (6 vs. 5%), protein (27 vs. 18%), and fiber (48 vs. 38%) in comparison to the seeds, and was hence considered a promising food ingredient. The major fatty acid in oil, seeds, and cake was α-linolenic acid (62-66%), and the vitamin E content was 409, 200, and 44 mg/kg, respectively. The major amino acid in the seeds and cake was glutamic acid (49 vs. 36 mg/g). The oil had a low oxidative stability (1 h), and the total phenolics content was 1.3 mg gallic acid equivalents/100 g. Chia cake incorporation in food formulations will follow consumer's interests, and the obtained oil can be used to improve the oil supply for different applications. This approach adds value to the concept of "one health" since it includes the culture, the environment, and the consumers.


Asunto(s)
Salvia , Semillas , Semillas/química , Extractos Vegetales/análisis , Ácidos Grasos/análisis , Grano Comestible/metabolismo , Aceites de Plantas/química , Salvia/química
7.
Molecules ; 28(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36985848

RESUMEN

Olive pomace is a by-product from olive oil production that can be further processed to obtain olive pomace paste. In this work, the influence of different time/temperature binomials (65 °C/30 min; 77 °C/1 min; 88 °C/15 s; and 120 °C/20 min) on the nutritional quality, chemical composition, and efficiency on control/elimination of natural microbial load of olive pomace paste was ascertained. The treatments significantly impacted the contents of ash, fat, vitamin E, phenolics (including hydroxytyrosol), flavonoids, and antioxidant activity, but not the fatty acids profile. The binomial 88 °C/15 s showed the greatest potential since it better preserved the phytochemical and antioxidant properties as well as the protein and fiber contents. This binomial is also faster and easy to be implemented at an industrial level, allowing the obtention of a safe functional ingredient to satisfy consumers' demands for novel sustainable products, simultaneously, responding to food safety and food security concerns.


Asunto(s)
Antioxidantes , Olea , Antioxidantes/farmacología , Olea/química , Temperatura , Aceite de Oliva , Vitamina E
8.
Compr Rev Food Sci Food Saf ; 22(1): 287-332, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36479852

RESUMEN

The coffee industry is one of the most important commercial value chains worldwide. Nonetheless, it is also associated to several social, economic, and environmental concerns that impair its sustainability. The present review is focused on these main sustainability concerns from the field to the coffee cup, as well as on the strategies that are being developed and/or implemented to attain sustainability and circular economy principles in the different chain segments. In this context, distinct approaches have been applied, such as sustainable certifications (e.g., voluntary sustainability standards), corporate sustainability initiatives, direct trade, relationship coffee concepts, geographical indication, legislations, waste management, and byproducts valorization, among others. These strategies are addressed and discussed throughout this review, as well as their recognized advantages and limitations. Overall, there is still a long way to go to attain the much-desired sustainability in the coffee chain, being essential to join the efforts of all actors and entities directly or indirectly involved, namely, producers, retailers, roasters, governments, educational institutions (such as universities and scientific research institutes), and organizations.


Asunto(s)
Café
9.
Environ Monit Assess ; 195(11): 1305, 2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828253

RESUMEN

The use of techniques based on artificial intelligence and machine learning for the simulation of many processes is becoming increasingly important in environmental sciences, with applications in the study of time series of atmospheric properties, such as pollution levels. The present work aimed to evaluate the efficiency of a model based on Artificial Neural Networks (ANN) in the simulation PM10 from meteorological data observed between 2018 and 2019 in Guaíba, southern Brazil, thus also having an estimate of the influence of atmospheric conditions on local air pollution. For this purpose, meteorological and PM10 data obtained from the stations Parque 35, sustained by Celulose Riograndense (CMPC), and A-801, sustained by the National Institute of Meteorology (INMET), were used. The ANN used for the simulation was of the Multilayer Perceptron type, trained by the backpropagation algorithm with cross-validation. The results obtained indicate that the simulation was satisfactory with a Nash-Sutcliffe index (NSE) of 0.64, a linear correlation coefficient (R) of 0.81, a relative error (Er) of 26% and a root mean square error (RMSE) of 7.40 µg/m3. Thus, even with some difficulty in estimating extreme concentrations, the model was suitable for the largest range observed, of 10 µg/m3 to 50 µg/m3. For this dataset, the model proved to be an useful assessment tool and has the potential to be applied operationally to contribute to the monitoring and control of air quality levels both in the study area and in other regions of Brazil and the world.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado/análisis , Inteligencia Artificial , Meteorología , Monitoreo del Ambiente/métodos , Redes Neurales de la Computación , Contaminantes Atmosféricos/análisis
10.
Neuroimage ; 247: 118833, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34929382

RESUMEN

Noninvasively detecting and characterizing modulations in cellular scale micro-architecture remains a desideratum for contemporary neuroimaging. Diffusion MRI (dMRI) has become the mainstay methodology for probing microstructure, and, in ischemia, its contrasts have revolutionized stroke management. Diffusion kurtosis imaging (DKI) has been shown to significantly enhance the sensitivity of stroke detection compared to its diffusion tensor imaging (DTI) counterparts. However, the interpretation of DKI remains ambiguous as its contrast may arise from competing kurtosis sources related to the anisotropy of tissue components, diffusivity variance across components, and microscopic kurtosis (e.g., arising from cross-sectional variance, structural disorder, and restriction). Resolving these sources may be fundamental for developing more specific imaging techniques for stroke management, prognosis, and understanding its pathophysiology. In this study, we apply Correlation Tensor MRI (CTI) - a double diffusion encoding (DDE) methodology recently introduced for deciphering kurtosis sources based on the unique information captured in DDE's diffusion correlation tensors - to investigate the underpinnings of kurtosis measurements in acute ischemic lesions. Simulations for the different kurtosis sources revealed specific signatures for cross-sectional variance (representing neurite beading), edema, and cell swelling. Ex vivo CTI experiments at 16.4 T were then performed in an experimental photothrombotic stroke model 3 h post-stroke (N = 10), and successfully separated anisotropic, isotropic, and microscopic non-Gaussian diffusion sources in the ischemic lesions. Each of these kurtosis sources provided unique contrasts in the stroked area. Particularly, microscopic kurtosis was shown to be a primary "driver" of total kurtosis upon ischemia; its large increases, coupled with decreases in anisotropic kurtosis, are consistent with the expected elevation in cross-sectional variance, likely linked to beading effects in small objects such as neurites. In vivo experiments at 9.4 T at the same time point (3 h post ischemia, N = 5) demonstrated the stability and relevance of the findings and showed that fixation is not a dominant confounder in our findings. In future studies, the different CTI contrasts may be useful to address current limitations of stroke imaging, e.g., penumbra characterization, distinguishing lesion progression form tissue recovery, and elucidating pathophysiological correlates.


Asunto(s)
Imagen de Difusión Tensora/métodos , Interpretación de Imagen Asistida por Computador/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Animales , Anisotropía , Masculino , Ratones , Ratones Endogámicos C57BL , Método de Montecarlo , Accidente Cerebrovascular/fisiopatología
11.
Health Qual Life Outcomes ; 20(1): 36, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35241084

RESUMEN

BACKGROUND: To describe the reduced health-related quality of life (HRQoL) of duchenne muscular dystrophy (DMD) patients and their caregiver burden and to present its relationship with disease progression. METHODS: This cross-sectional study assessed patient HRQoL with the 3-level version of the EuroQol-5D (EQ-5D-3L) and caregiver burden with the Work Productivity and Activity Impairment: General Health questionnaire. DMD patients and their caregivers were identified through Portuguese Neuromuscular Association (APN). RESULTS: A total of 46 DMD main caregivers, of eight ambulant and 38 non-ambulant patients, completed the questionnaires. Over half (58.7%) of all non-ambulant patients were on ventilation support, either full-time (15.2%) or non full-time (43.5%). Non-ambulant patients had a lower mean utility scores than ambulant patients (- 0.05 versus 0.51, p value < 0.001). Caregivers of non-ambulant patients reported a significant mean daily activity impairment as compared to caregivers of ambulant patients (68% versus 23%, p value < 0.001). Among non-ambulant patients, both utility scores and caregiver impairment appeared to deteriorate according to a higher need for ventilation support, however, these results were not statistically significant. CONCLUSIONS: These results emphasise the significant negative impact that DMD progression has on the patient HRQoL, as well as caregivers' ability to conduct their daily activities. Therapeutic options that stop or slow the disease progression could have a beneficial impact for both patients and caregivers.


Asunto(s)
Distrofia Muscular de Duchenne , Calidad de Vida , Carga del Cuidador , Cuidadores , Estudios Transversales , Humanos , Distrofia Muscular de Duchenne/terapia , Atención al Paciente , Portugal , Encuestas y Cuestionarios
12.
Compr Rev Food Sci Food Saf ; 21(2): 1125-1160, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35080792

RESUMEN

The new trends in drying technology seek a promising alternative to synthetic preservatives to improve the shelf-life and storage stability of food products. On the other hand, the drying process can result in deformation and degradation of phytoconstituents due to their thermal sensitivity. The main purpose of this review is to give a general overview of common drying techniques with special attention to food industrial applications, focusing on recent advances to maintain the features of the active phytoconstituents and nutrients, and improve their release and storage stability. Furthermore, a drying technique that extends the shelf-life of food products by reducing trapped water, will negatively affect the spoilage of microorganisms and enzymes that are responsible for undesired chemical composition changes, but can protect beneficial microorganisms like probiotics. This paper also explores recent efficient improvements in drying technologies that produce high-quality and low-cost final products compared to conventional methods. However, despite the recent advances in drying technologies, hybrid drying (a combination of different drying techniques) and spray drying (drying with the help of encapsulation methods) are still promising techniques in food industries. In conclusion, spray drying encapsulation can improve the morphology and texture of dry materials, preserve natural components for a long time, and increase storage times (shelf-life). Optimizing a drying technique and using a suitable drying agent should also be a promising solution to preserve probiotic bacteria and antimicrobial compounds.


Asunto(s)
Desecación , Probióticos , Industria de Alimentos , Inocuidad de los Alimentos
13.
Clin Nephrol ; 96(2): 124-128, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34032207

RESUMEN

Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, and renal injury, which results from thrombotic microangiopathy (TMA) within the glomerular capillaries and arterioles. We report a case of a biopsy-proven renal TMA attributed to hypertension in a 42-year-old woman with undiagnosed alternative complement pathway dysregulation resulting from a rare association between complement factor H (CFH) autoantibodies and a heterozygous variant in the CFH gene. We propose that severe hypertension triggered an over-activation of the alternative complement pathway in a patient with genetic predisposition. In this case, blood pressure control allowed normalization of hematologic parameters and partial recovery of renal function, supporting the idea that shear stress is an important complement-amplifying factor.


Asunto(s)
Autoanticuerpos/sangre , Factor H de Complemento , Hipertensión , Microangiopatías Trombóticas , Adulto , Factor H de Complemento/genética , Factor H de Complemento/inmunología , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Microangiopatías Trombóticas/sangre , Microangiopatías Trombóticas/diagnóstico , Microangiopatías Trombóticas/etiología
14.
J Plant Res ; 134(6): 1279-1289, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34302571

RESUMEN

Salinity has become one of the major factors limiting agricultural production. In this regard, different cost-effective management strategies such as the use of plant growth-promoting bacteria (PGPB) as inoculants to alleviate salt-stress conditions and minimize plant productivity losses have been used in agricultural systems. The aim of this study was to characterize induced antioxidant responses in corn through inoculation with Azospirillum brasilense and examine the relationship between these responses and the acquired salt-stress tolerance. Treatments were performed by combining sodium chloride (0 and 100 mM NaCl) through irrigation water with absence and presence of A. brasilense inoculation. The experiment was performed in a completely randomized design with four replications. Lipid peroxidation (malondialdehyde [MDA]), and nitrogen (N), sodium (Na+) and potassium (K+) contents, as well as dry biomass, glycine betaine, and antioxidant enzymes activities such as of superoxide dismutase (SOD, EC 1. 15. 1. 1), glutathione reductase (GR, EC 1. 6. 4. 2), guaiacol peroxidase (GPOX, EC 1. 11. 1. 7), and glutathione peroxidase (GSH-PX, EC 1. 11. 1. 9) were determined. Overall results indicated that plants treated with 100 mM NaCl showed the most pronounced salt-stress damages with consequent increase in MDA content. However, inoculated plants showed an enhanced capacity to withstand or avoid salt-stress damages. These results could be attributed, at least in part, to the increased activity of antioxidant enzymes. Our results suggest that A. brasilense may confer tolerance to salt stress in corn plants enhancing antioxidant responses, primarily by the enzymes GSH-PX and GPOX, and the osmolyte glycine betaine.


Asunto(s)
Antioxidantes , Azospirillum brasilense , Malondialdehído , Estrés Oxidativo , Salinidad , Tolerancia a la Sal , Zea mays
15.
An Acad Bras Cienc ; 93(3): e20190157, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34161509

RESUMEN

Six events of explosive cyclogenesis occurred in the south Atlantic were compared using reanalysis data and satellite water vapor imagery. Cases of different intensities (weak, moderate and strong) occurred during 2014 summer season and 2012 winter season were studied. Despite the similarities the tropopause anomaly was more prominent and vertical movements were stronger in the strong cyclogenesis cases. The tropopause anomalies behind the cold front and ahead of the warm front appear only in the mature stage of the weak and moderate cases while in the strong case it is already evident and more intense behind the cold front since the beginning of the cycle. In all the cases confluence of the jet streams took place at higher levels forming a jet streak with difluence occurring downstream and the cyclone beginning in the exit region. The trajectories of the cyclones were in the southeast direction but longer and more meridional in the strong cases. The results indicated the baroclinicity of the region as the main mechanism for the development of these cyclones as well as the amplitude of the upper level jet stream perturbation. Furthermore, all the explosive cyclones developed following the Shapiro & Keyser cyclone conceptual model.


Asunto(s)
Tormentas Ciclónicas , Sustancias Explosivas , Modelos Teóricos , Estaciones del Año
16.
An Acad Bras Cienc ; 93(3): e20201278, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34161514

RESUMEN

This study aimed to classify the homogeneous regions of vegetation cover, which occur in Rio Grande do Sul, formed by clustering of pixels with same pattern of temporal variability of the Normalized Difference Vegetation Index (NDVI) of AVHRR GIMMS and MODIS series and to compare their temporal dynamics. We use K means cluster analysis for defining homogeneous regions, based on the temporal variability of GIMMS (8 km spatial resolution) and MODIS (1 km spatial resolution) NDVI data sets, using monthly images mean from 2000 to 2008 (overlapping period); and we analyzed the annual pattern of NDVI. Accuracy assessment was done with Landsat images. The results show that the temporal variability of GIMMS and MODIS NDVI allows to delimit similar homogeneous regions in order to mapping the main vegetation cover. MODIS series shows a greater detail in the definition of the regions, but with compatibility with those generated by GIMMS. The temporal dynamics show a typical seasonal pattern, with variations of NDVI amplitude between the groups, that allow to monitor phenological changes. The deviations from calibration between times series are linear, which would facilitate a correction in order to construct a long synthetic time series for studies of land cover change.


Asunto(s)
Monitoreo del Ambiente , Brasil
17.
Chem Biodivers ; 18(6): e2100071, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33871171

RESUMEN

The lipid fraction of seeds from different pine species and populations was studied regarding total lipid content, fatty acid profile and vitamin E composition. The investigated seeds contained a high percentage of lipid (13.6 to 31.5 %). Lipid fractions were found to be rich in vitamin E, which varied significantly among species and populations. P. halepensis (Ph-Hn) showed the highest content of vitamin E (256.3 mg/kg of seeds) and the uppermost content of α-tocopherol (44 mg/kg). However, P. halepensis (Ph-Kas) was the richest in γ-tocopherol (204.9 mg/kg). Lipid fractions had a low content of δ-tocopherol (1.2 to 3.6 mg/kg. The highest content of γ-tocotrienol (∼18 %) was determined for P. halepensis (Ph-Dc and Ph-Hn). Thirteen fatty acids were identified by GC-FID with significant variation between the investigated species. The linoleic acid was the major fatty acid followed by oleic acid and palmitic acid. The chemical differentiation among species for the composition of fatty acids and vitamin E was confirmed by PCA. Significant correlations were observed between the content of vitamin E and fatty acids and ecological parameters of P. halepensis populations.


Asunto(s)
Ácidos Grasos/análisis , Lípidos/análisis , Pinus/química , Vitamina E/análisis , Pinus/clasificación , Semillas/química , Túnez
18.
Molecules ; 26(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34641482

RESUMEN

Gunnera tinctoria, an underexplored invasive plant found in Azores, Portugal, was studied regarding its nutritional, antioxidant, and antitumoral properties. Higher antioxidant activity was found in baby leaves, followed by adult leaves and inflorescences. A phenolic fraction of the plant was enriched using adsorbent resin column chromatography (DiaionTM HP20LX, and Relite EXA90). Antitumoral effects were observed with the enriched fractions in breast (MCF-7) and pancreatic (AsPC-1) cancer cell lines, being more pronounced in the latter. To improve protection and membrane absorption rates of phenolic compounds, nano-phytosomes and cholesterol-conjugated phytosomes coated with natural polymers were loaded with the enriched fraction. The particles were characterized, and their physiochemical properties were evaluated and compared. All samples presented anionic charge and nanometer size in relation to the inner layer and micrometer size regarding the external layers. In addition, the molecular arrangement of phenolics within both types of phytosomes were studied for the first time by molecular docking. Polarity and molecular size were key factors on the molecular arrangement of the lipid bilayer. In conclusion, G. tinctoria showed to be an interesting source of nutrients and phenolic compounds with anti-tumoral potential. Moreover, phytosome loading with these compounds can increase their stability and bioavailability having in view future applications.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Magnoliopsida/química , Neoplasias/tratamiento farmacológico , Extractos Vegetales/farmacología , Humanos , Simulación del Acoplamiento Molecular , Neoplasias/patología , Valor Nutritivo , Células Tumorales Cultivadas
19.
Neuroimage ; 214: 116728, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32199954

RESUMEN

A growing literature supports the existence of interactions between emotion and action in the brain, and the central participation of the anterior midcingulate cortex (aMCC) in this regard. In the present functional magnetic resonance imaging study, we sought to investigate the role of self-relevance during such interactions by varying the context in which threating pictures were presented (with guns pointed towards or away from the observer). Participants performed a simple visual detection task following exposure to such stimuli. Except for voxelwise tests, we adopted a Bayesian analysis framework which evaluated evidence for the hypotheses of interest, given the data, in a continuous fashion. Behaviorally, our results demonstrated a valence by context interaction such that there was a tendency of speeding up responses to targets after viewing threat pictures directed towards the participant. In the brain, interaction patterns that paralleled those observed behaviorally were observed most notably in the middle temporal gyrus, supplementary motor area, precentral gyrus, and anterior insula. In these regions, activity was overall greater during threat conditions relative to neutral ones, and this effect was enhanced in the directed towards context. A valence by context interaction was observed in the aMCC too, where we also observed a correlation (across participants) of evoked responses and reaction time data. Taken together, our study revealed the context-sensitive engagement of motor-related areas during emotional perception, thus supporting the idea that emotion and action interact in important ways in the brain.


Asunto(s)
Emociones/fisiología , Giro del Cíngulo/fisiología , Actividad Motora/fisiología , Tiempo de Reacción/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino
20.
Ecotoxicol Environ Saf ; 201: 110778, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32480161

RESUMEN

Field peas (Pisum sativum L.) are widely cultivated throughout the world as a cool season grain and forage crop. Boron (B) toxicity is caused by high B concentration in the soil or irrigation water, and is particularly problematic in medium or heavier textured soil types with moderate alkalinity and low annual rainfall. Previous studies have indicated that B-toxicity increases oxidative stress in plants, and B-tolerance has been considered an important target in field pea plant breeding programmes. Inducers of tolerance may be a promising alternative for plant breeding. Little research has been conducted on the combined use of silicon (Si) and salicylic acid (SA) to remediate B-toxicity in field peas. The present study revealed the physiological and biochemical plant responses of applying Si + SA under B-toxicity (15 mg B L-1) on two Brazilian field pea cultivars (Iapar 83 and BRS Forrageira). A semi-hydroponic experiment was conducted using a completely randomized factorial design (2 × 5): with two field pea cultivars and five treatments which were formed by individual and combined applications of Si and SA under B-toxicity plus a control (control, B, B + Si, B + SA, and B + Si + SA). Si (2 mmol L-1) was applied to plants in two forms (root and leaf), while for SA (36 µmol L-1) only foliar applications were applied. Our results demonstrated that the combined use of exogenous Si + SA in field peas increased tolerance to B-toxicity through an intensified antioxidant plant defence system, resulting in a better regulation of reactive oxygen species (ROS) production and degradation. It significantly increased total chlorophyll and carotenoids contents, the activities of major antioxidant enzymes, and reduced MDA and H2O2 contents, resulting in increased fresh shoot and total plant dry biomass. The application of Si + SA alleviated the inhibitory effects of boron toxicity in field peas, resulting in greater plant growth by preventing oxidative membrane damage through an increased tolerance to B-excess within the plant tissue. Therefore, the use of Si + SA is an important and sustainable strategy to alleviate B-toxicity in field pea cultivation.


Asunto(s)
Antioxidantes/metabolismo , Boro/toxicidad , Pisum sativum/fisiología , Ácido Salicílico/metabolismo , Silicio/metabolismo , Contaminantes del Suelo/toxicidad , Brasil , Clorofila/metabolismo , Peróxido de Hidrógeno/metabolismo , Estrés Oxidativo/efectos de los fármacos , Pisum sativum/efectos de los fármacos , Hojas de la Planta/metabolismo , Especies Reactivas de Oxígeno/metabolismo
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