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1.
PLoS One ; 19(3): e0298322, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38502658

RESUMO

Many proteins in higher eukaryotes, especially those with crucial functions, have multiple isoforms with redundant roles providing protection against potential functional deficiencies in one isoform. However, these isoforms can also have some unique roles. Protein kinase B, also known as Akt, is one such protein that has three isoforms encoded on different genes. Due to high sequence similarity and the general lack of specific reagents, most studies on Akt generalize their findings and do not distinguish between the isoforms. Using an established chemical genetic strategy and a set of known Akt substrates, this work explores substrate specificity of Akt isoforms under steady state conditions in two commonly used cell lines. This strategy can be applied to study any Akt isoform-specific substrates of interest in any cell line of choice as long as the cell line can be transfected.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-akt/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Linhagem Celular
2.
Foods ; 12(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37835361

RESUMO

The fruits of Arbutus unedo L. have a crimson colour and are enriched with remarkable concentrations of bioactive compounds such as anthocyanins and polyphenols. These fruits are commonly used in the production of a Portuguese Protected Geographical Indication distillate called "Aguardente de Medronho". During this process, a solid pomace is generated and presently discarded without valuable applications. In this work, two strategies have been developed for the valorisation of A. unedo pomace. The first approach considers the extraction of polyphenols from this by-product through the optimization of an ultrasound-assisted method using a Box-Behnken design coupled with response surface methodology. The results indicate that the temperature and the percentage of methanol, along with their interaction, significantly influence the total concentration of polyphenols and the antioxidant activity of the extracts obtained. The optimal conditions identified consider the extraction of 0.5 g of sample with 20 mL of a solvent containing 74% MeOH (aq), at a pH of 4.8, maintained at 70 °C for 15 min. On the other hand, the second valorisation strategy considered the use of A. unedo pomace in the development of functional cookies. The incorporation of 15-20% pomace in the cookie formulation was well-received by consumers. This incorporation results in an intake of ca. 6.55 mg of polyphenols per gram of cookie consumed, accompanied by an antioxidant activity of 4.54 mg Trolox equivalents per gram of cookie consumed. Overall, these results encourage the employment of A. unedo pomace either as a reliable source of extracts enriched in polyphenols or as a nutraceutical active ingredient in functional cookies, thereby positively impacting human health.

3.
Pharmaceuticals (Basel) ; 16(5)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37242498

RESUMO

The population is now more aware of their diets due to the connection between food and general health. Onions (Allium cepa L.), common vegetables that are minimally processed and grown locally, are known for their health-promoting properties. The organosulfur compounds present in onions have powerful antioxidant properties and may decrease the likelihood of developing certain disorders. It is vital to employ an optimum approach with the best qualities for studying the target compounds to undertake a thorough analysis of these compounds. In this study, the use of a direct thermal desorption-gas chromatography-mass spectrometry method with a Box-Behnken design and multi-response optimization is proposed. Direct thermal desorption is an environmentally friendly technique that eliminates the use of solvents and requires no prior preparation of the sample. To the author's knowledge, this methodology has not been previously used to study the organosulfur compounds in onions. Likewise, the optimal conditions for pre-extraction and post-analysis of organosulfur compounds were as follows: 46 mg of onion in the tube, a desorption heat of 205 °C for 960 s, and a trap heat of 267 °C for 180 s. The repeatability and intermediate precision of the method were evaluated by conducting 27 tests over three consecutive days. The results obtained for all compounds studied revealed CV values ranging from 1.8% to 9.9%. The major compound reported in onions was 2,4-dimethyl-thiophene, representing 19.4% of the total area of sulfur compounds. The propanethial S-oxide, the principal compound responsible for the tear factor, accounted for 4.5% of the total area.

4.
Antioxidants (Basel) ; 11(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36552601

RESUMO

Nowadays, consumers demand bioactive foods that have the potential to limit the risk of suffering from several medical conditions. Onions present these desirable capabilities owing to its high content in antioxidant bioactive compounds. This work has used a Box-Behnken design with a response surface methodology to determine the best conditions in which to extract the polyphenols that are found in onions. Two extraction methods-one for the extraction of total flavonols and another one intended to obtain extracts with the highest possible antioxidant activity-have been developed and optimized. The following factors have been studied: temperature, %methanol in water, solvent pH, and sample-solvent volumetric ratio. The optimal conditions for the extraction of flavonols were 93.8% methanol in water, pH 2, 50 °C extraction temperature and 0.2:17.9 g:mL sample-solvent ratio. The best antioxidant activity levels were registered when using 74.2% methanol in water, pH 2, 99.9 °C extraction temperature and 0.2:18.2 g:mL sample-solvent ratio. Both optimized methods used short extraction times, and presented good precision levels and successful results when used with an assortment of onion varieties. According to total flavonols and antioxidant activity data, with 7.557 ± 0.3261 and 12.08 ± 0.0379 mg g-1, respectively, the developed methods achieved comparable or even superior results to those obtained by other authors.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35329348

RESUMO

There is high concern about the exposure of firefighters to toxic products or carcinogens resulting from combustion during fire interventions. Firefighter turnout gear is designed to protect against immediate fire hazards but not against chemical agents. Additionally, the decontamination of firefighter personal protective equipment remains unresolved. This study evaluated the feasibility of a screening method based on headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) in combination with chemometrics (cluster analysis, principal component analysis, and linear discriminant analysis) for the assessment of the transference of volatile compounds through turnout gear. To achieve this, firefighter turnout gears exposed to two different fire scenes (with different combustion materials) were directly analyzed. We obtained a spectral fingerprint for turnout gears that were both exposed and non-exposed to fire scenes. The results showed that (i): the contamination of the turnout gears is different depending on the type of fire loading; and (ii) it is possible to determine if the turnout gear is free of volatile compounds. Based on the latest results, we concluded that HS-GC-IMS can be applied as a screening technique to assess the quality of turnout gear prior to a new fire intervention.


Assuntos
Bombeiros , Incêndios , Exposição Ocupacional , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Exposição Ocupacional/análise , Equipamento de Proteção Individual , Compostos Orgânicos Voláteis/análise
6.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068086

RESUMO

Erica australis plants have been used in infusions and folk medicine for years for its diuretic and antiseptic properties and even for the treatment of infections. In addition, a recently published thorough study on this species has demonstrated its antioxidant, antibiotic, anti-inflammatory, anticarcinogenic and even antitumoral activities. These properties have been associated with the high content of anthocyanins in E. australis leaves and flowers. The aim of the present research is to optimize an ultrasound-assisted extraction methodology for the recovery of the anthocyanins present in E. australis flowers. For that purpose, a Box Behnken design with response surface methodology was employed, and the influence of four variables at different values was determined: namely, the composition of the extraction solvents (0-50% MeOH in water), the pH level of those solvents (3-7), the extraction temperature (10-70 °C), and the sample:solvent ratio (0.5 g:10 mL-0.5 g:20 mL). UHPLC-UV-vis has been employed to quantify the two major anthocyanins detected in the samples. The extraction optimum conditions for 0.5 g samples were: 20 mL of solvent (50% MeOH:H2O) at 5 pH, with a 15 min extraction time at 70 °C. A precision study was performed and the intra-day and inter-day relative standard deviations (RSDs) obtained were 3.31% and 3.52%, respectively. The developed methodology has been successfully applied to other Erica species to validate the suitability of the method for anthocyanin extraction.


Assuntos
Antocianinas/análise , Ericaceae/química , Flores/química , Ultrassom/métodos , Cromatografia Líquida de Alta Pressão , Metanol/química , Padrões de Referência , Temperatura , Fatores de Tempo
7.
Biomolecules ; 11(2)2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562786

RESUMO

Thinning is a common viticulture practice in warm climates, and it is applied to increase the quality of the harvest. Thinning clusters are usually discarded, and they are considered another oenological industry waste. To valorize this by-product, the phenolic content and antioxidant activity of three red varieties (Tempranillo, Cabernet Sauvignon, and Syrah), thinned at three different times between veraison and harvest, were studied: the first at the beginning of the veraison stage, in a low ripening stage; the second in an intermediate ripening stage; and, finally, the third sampling in the highest ripening stage. These by-products showed high values of total phenolic contents (10.66-11.75 mg gallic acid equivalent/g), which is of the same order as or even higher than that found in grape pomace. In thinned grape were identified 24 phenolic compounds, being the flavan-3-ols (catechin and epicatechin) of particular interest, with mean contents ranging from 105.1 to 516.4 mg/kg of thinned grape. Antioxidant activity similar to that of the vintage grape was found. It is concluded that thinned grape is a good source of phenolic compounds. Its content does not depend mainly on the grape variety; however, it has been possible to establish differences based on the maturity stage of the thinning grapes: the intermediate ripeness stage, with a Brix degree in the range of 15-16 for this area, would be the optimum collection time for cluster thinning. In this intermediate ripeness stage, thinning grapes present a higher antioxidant activity and there is also appreciable anthocyanin content, which is not found for the lowest ripeness stage, since these samples present an intermediate composition in all the families of determined phenolic compounds: anthocyanins, flavonols, flavan-3-ols, cinnamic acids, and benzoic acids. It is important to note that the experiments in this study have been carried out with whole tinned grapes, without separating the skin or the seeds.


Assuntos
Antioxidantes/química , Frutas/química , Polifenóis/química , Vitis/química , Resíduos/análise , Antocianinas/química , Antocianinas/isolamento & purificação , Antioxidantes/isolamento & purificação , Benzoatos/química , Benzoatos/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Cinamatos/química , Cinamatos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Vinho/análise
8.
Foods ; 9(12)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260750

RESUMO

In recent years, consumers' preference for fruits such as blueberry has increased noticeably. This fact is probably related to their bioactive components such as anthocyanins, phenolic compounds, vitamins, minerals, and tannins that have been found in blueberries by the latest research studies. Both total anthocyanins (TA) and total phenolic compounds (TPC) are known for their multiple beneficial effects on our health, due to their anti-inflammatory, anti-oxidant, and anti-cancer properties. This is the reason why the development of new methodologies for the quality control analysis of raw materials or derived products from blueberry has a great relevance. Two ultrasound-assisted extraction methods (UAE) have been optimized for the quantification of TA and TPC in blueberry samples. The six variables to be optimized were: solvent composition, temperature, amplitude, cycle, extraction solvent pH, and sample/solvent ratio using response surface methodology. The optimized methods have proven to be suitable for the extraction of the TPC and TA with good precision (repeatability and intermediate precision) (coefficient of variation (CV) < 5%) and potentially for application in commercial samples. This fact, together with the multiple advantages of UAE, makes these methods a good alternative to be used in quality control analysis by both industries and laboratories.

9.
Food Chem ; 220: 331-336, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855908

RESUMO

Adulteration of olive oil is not only a major economic fraud but can also have major health implications for consumers. In this study, a combination of visible spectroscopy with a novel multivariate curve resolution method (CR), principal component analysis (PCA) and linear discriminant analysis (LDA) is proposed for the authentication of virgin olive oil (VOO) samples. VOOs are well-known products with the typical properties of a two-component system due to the two main groups of compounds that contribute to the visible spectra (chlorophylls and carotenoids). Application of the proposed CR method to VOO samples provided the two pure-component spectra for the aforementioned families of compounds. A correlation study of the real spectra and the resolved component spectra was carried out for different types of oil samples (n=118). LDA using the correlation coefficients as variables to discriminate samples allowed the authentication of 95% of virgin olive oil samples.


Assuntos
Azeite de Oliva/química , Clorofila , Análise Discriminante , Análise de Componente Principal , Análise Espectral
10.
Anal Chim Acta ; 732: 100-4, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22688040

RESUMO

A new ultrasound-assisted extraction method was developed for the determination of phenolic compounds present in grapes. Several extraction variables including extraction temperature (0-75°C), output amplitude (20, 50 and 100%), duty cycle (0.2 s, 0.6 s and 1 s), the quantity of sample (0.5-2 g), and the total extraction time (3-15 min) were evaluated. One of the most widely used extraction methods of polyphenol extraction has been used as reference method. Three parameters were compared: total amount of phenolic compounds, total amount of anthocyanins and total amount of tannic components. The resulting method produced similar or higher recoveries for these three parameters; however a much shorter extraction time was needed: 6 min (ultrasound assisted extraction method) instead of 60 min (reference method). Analytical properties for the new method were established, including limit of detection, limit of quantification, repeatability and reproducibility. The developed method was applied to two different types of grapes in different ripening degree.


Assuntos
Fenóis/química , Sonicação , Vitis/química , Antocianinas/química , Taninos/química , Temperatura , Fatores de Tempo
11.
Acta Otorrinolaringol Esp ; 58(10): 483-6, 2007 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-18082079

RESUMO

Three cases of rare entities in nasal pathology are reported. Two of them are high-grade lymphomas (T/NK type), with nasal blockage as the first symptom. Clinical course and treatment response are described. The third case refers to an infrequent benign nasal entity called angiocentric eosinophilic fibrosis. Its aetiology and management remains rather uncertain nowadays.


Assuntos
Eosinofilia/complicações , Eosinofilia/patologia , Fibrose/complicações , Fibrose/patologia , Linfoma não Hodgkin/patologia , Doenças dos Seios Paranasais/complicações , Doenças dos Seios Paranasais/patologia , Adulto , Idoso , Antígeno CD56/metabolismo , Eosinofilia/metabolismo , Feminino , Fibrose/metabolismo , Humanos , Células Matadoras Naturais/metabolismo , Masculino , Seio Maxilar/metabolismo , Seio Maxilar/patologia , Doenças dos Seios Paranasais/metabolismo , Linfócitos T/metabolismo
12.
Rev. cuba. pediatr ; 58(4): 495-502, jul.-ago. 1986.
Artigo em Espanhol | LILACS | ID: lil-44245

RESUMO

El reflujo vesicoureteral es la uropatía más común en nuestro medio; de las numerosas publicaciones realizadas a este respecto, la relación entre reflujo vesicoureteral, infección urinaria y lesión renal es aún motivo de discusión. Con el objetivo de analizar estos factores se realiza un estudio de 122 pacientes atendidos en nuestro hospital. Se analiza la edad del diagnóstico, la frecuencia de acuerdo con el sexo, la nutrición y la evolución de la enfermedad acorde con el tratamiento médico o quirúrgico, para valorar la posible aplicación de medidas preventivas que puedan disminuir la morbimortalidad y la progresión a insuficiencia renal terminal


Assuntos
Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Humanos , Masculino , Feminino , Estudos Retrospectivos , Refluxo Vesicoureteral , Refluxo Vesicoureteral/epidemiologia , Estudos de Casos e Controles , Refluxo Vesicoureteral/diagnóstico , Refluxo Vesicoureteral/terapia
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