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1.
Br J Radiol ; 97(1153): 21-30, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263828

RESUMO

Many different malignancies occur in children, but overall, cancer in childhood is rare. Survival rates have improved appreciably and are higher compared with most adult tumour types. Treatment schedules evolve as a result of clinical trials and are typically complex and multi-modality, with radiotherapy an integral component of many. Risk stratification in paediatric oncology is increasingly refined, resulting in a more personalized use of radiation. Every available modality of radiation delivery: simple and advanced photon techniques, proton beam therapy, molecular radiotherapy, and brachytherapy, have their place in the treatment of children's cancers. Radiotherapy is rarely the sole treatment. As local therapy, it is often given before or after surgery, so the involvement of the surgeon is critically important, particularly when brachytherapy is used. Systemic treatment is the standard of care for most paediatric tumour types, concomitant administration of chemotherapy is typical, and immunotherapy has an increasing role. Delivery of radiotherapy is not done by clinical or radiation oncologists alone; play specialists and anaesthetists are required, together with mould room staff, to ensure compliance and immobilization. The support of clinical radiologists is needed to ensure the correct interpretation of imaging for target volume delineation. Physicists and dosimetrists ensure the optimal dose distribution, minimizing exposure of organs at risk. Paediatric oncology doctors, nurses, and a range of allied health professionals are needed for the holistic wrap-around care of the child and family. Radiographers are essential at every step of the way. With increasing complexity comes a need for greater centralization of services.


Assuntos
Braquiterapia , Neoplasias , Radioterapia (Especialidade) , Adulto , Humanos , Criança , Oncologia , Reino Unido
2.
Foods ; 12(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37628030

RESUMO

The interest on the use of natural sources in the food industry has promoted the study of plants' phenolic compounds as potential additives. However, the literature has been focusing on essential oils, with very few studies published regarding aqueous extracts, their phenolic composition, and bioactivity. A systematic review was conducted on different databases following PRISMA guidelines to evaluate the relevance of the phenolic content of different aromatic spices (oregano, rosemary, thyme, ginger, clove, and pepper), as related to their bioactivity and potential application as food additives. Although different extraction methods have been applied in the literature, the use of green approaches using ethanol and deep eutectic solvents has increased, leading to the development of products more apt for human consumption. The studied plants present an interesting phenolic profile, ranging from phenolic acids to flavonoids, establishing a correlation between their phenolic content and bioactivity. In this sense, results have proven to be very promising, presenting those extracts as having similar if not higher bioactivity than synthetic additives already in use, with associated health concerns. Nevertheless, the study of spices' phenolic extracts is somehow limited to in vitro studies. Therefore, research in food matrices is needed for more understanding of factors interfering with their preservation activity.

3.
Plants (Basel) ; 12(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37447094

RESUMO

White willow (Salix alba) is a medicinal plant used in folk medicine. In this study, aqueous and ethanolic willow bark extracts were obtained via ultrasonic-assisted extraction (UAE) and microwave-assisted extraction (MAE), and analyzed regarding their phytochemical (total phenolics, phenolic acids, flavonoids, and tannins) content and in vitro biological properties (antibacterial and antifungal activity, acetylcholinesterase AChE inhibitory activity and anti-inflammatory effects). The highest phenolic, tannin, and flavonoid contents were found for willow bark extracts obtained via microwave-assisted extraction using ethanol as a solvent (SA-ME). The polyphenol load of all MAE and UAE extracts was higher when conventional solid-liquid extraction was applied (ρ < 0.05). The antioxidant capacities were stronger for microwave-assisted ethanolic extracts, with the lowest IC50 values of 12 µg/mL for DPPH• and a value of 16 µg/mL for ABTS•+, whereas the conventional extraction had the highest IC50 values (22 µg/mL and 28 µg/mL, respectively). Willow bark extract showed antibacterial activity against Gram-positive bacteria S. aureus and P. aeruginosa. AChE inhibitory activity was dependent on the extraction method and solvent used, and the highest inhibition among samples was observed for SA-ME. Taken altogether, our findings suggest that willow (Salix alba) bark extract obtained via ethanolic microwave-assisted extraction is a phytochemical-rich resource with in vitro, anti-inflammatory, and AchE inhibitory properties and, therefore, potential multiple medicinal end-uses.

5.
Med Sci Sports Exerc ; 47(9): 1965-78, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25628173

RESUMO

INTRODUCTION: This controlled, nonrandomized, parallel-groups trial investigated the effects on performance, V˙O2 and hemoglobin mass (tHbmass) of four preparatory in-season training interventions: living and training at moderate altitude for 3 and 4 wk (Hi-Hi3, Hi-Hi), living high and training high and low (Hi-HiLo, 4 wk), and living and training at sea level (SL) (Lo-Lo, 4 wk). METHODS: From 61 elite swimmers, 54 met all inclusion criteria and completed time trials over 50- and 400-m crawl (TT50, TT400), and 100 (sprinters) or 200 m (nonsprinters) at best stroke (TT100/TT200). Maximal oxygen uptake (V˙O2max) and HR were measured with an incremental 4 × 200 m test. Training load was estimated using cumulative training impulse method and session RPE. Initial measures (PRE) were repeated immediately (POST) and once weekly on return to SL (PostW1 to PostW4). tHbmass was measured in duplicate at PRE and once weekly during the camp with CO rebreathing. Effects were analyzed using mixed linear modeling. RESULTS: TT100 or TT200 was worse or unchanged immediately at POST, but improved by approximately 3.5% regardless of living or training at SL or altitude after at least 1 wk of SL recovery. Hi-HiLo achieved greater improvement 2 (5.3%) and 4 wk (6.3%) after the camp. Hi-HiLo also improved more in TT400 and TT50 2 (4.2% and 5.2%, respectively) and 4 wk (4.7% and 5.5%) from return. This performance improvement was not linked linearly to changes in V˙O2max or tHbmass. CONCLUSIONS: A well-implemented 3- or 4-wk training camp may impair performance immediately but clearly improves performance even in elite swimmers after a period of SL recovery. Hi-HiLo for 4 wk improves performance in swimming above and beyond altitude and SL controls through complex mechanisms involving altitude living and SL training effects.


Assuntos
Altitude , Desempenho Atlético/fisiologia , Educação Física e Treinamento/métodos , Natação/fisiologia , Adolescente , Suplementos Nutricionais , Feminino , Hemoglobinometria , Humanos , Ferro da Dieta/administração & dosagem , Masculino , Consumo de Oxigênio , Fatores de Tempo , Adulto Jovem
6.
PLoS One ; 9(9): e107749, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25248107

RESUMO

Structured Lipids are generally constituents of functional foods. Growing demands for SL are based on a fuller understanding of nutritional requirements, lipid metabolism, and improved methods to produce them. Specifically, this work was aimed to add value to avocado oil by producing dietary triacylglycerols (TAG) containing medium-chain fatty acids (M) at positions sn-1,3 and long-chain fatty acids (L) at position sn-2. These MLM-type structured lipids (SL) were produced by interesterification of caprylic acid (CA) (C8:0) and avocado oil (content of C18:1). The regiospecific sn-1,3 commercial lipases Lipozyme RM IM and TL IM were used as biocatalysts to probe the potential of avocado oil to produce SL. Reactions were performed at 30-50°C for 24 h in solvent-free media with a substrate molar ratio of 1∶2 (TAG:CA) and 4-10% w/w enzyme content. The lowest incorporation of CA (1.1% mol) resulted from Lipozyme RM IM that was incubated at 50°C. The maximum incorporation of CA into sn-1,3 positions of TAG was 29.2% mol. This result was obtained at 30°C with 10% w/w Lipozyme TL IM, which is the highest values obtained in solvent-free medium until now for structured lipids of low-calories. This strategy opens a new market to added value products based on avocado oil.


Assuntos
Lipase/metabolismo , Persea/química , Óleos de Plantas/química , Triglicerídeos/metabolismo , Biocatálise , Caprilatos/metabolismo , Gorduras na Dieta/metabolismo , Enzimas Imobilizadas/metabolismo , Esterificação , Óleos de Plantas/metabolismo , Triglicerídeos/química
7.
Food Chem ; 139(1-4): 138-43, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23561089

RESUMO

We evaluate the total phenolic compounds (TPC) content and the antioxidant activity (AA) of extracts obtained from ground fresh thyme (FT) and depleted thyme (DT), a by-product of the process of essential oil extraction. In addition, enzymatic treatments were evaluated to improve the extraction yields of polyphenolic compounds from thyme. Extractions were performed using several solvents as methanol, ethanol, and water. Enzymes were applied prior to extraction or during the extraction process. The best results were obtained using a mixture of methanol and water, resulting in 2790 and 220 mg Gallic acid equivalent (GAE)/L of TPC for FT and DT, respectively. A similar result was observed for AA. With regard to enzymatic treatment, application of Grindamyl CA 150 enzyme as a pre-treatment resulted in the production of an extract from DT with 614 mg TE (trolox equivalent)/L of AA, 70% more than the control, and an AA of 621 mg TE/L (74% more than the control sample) was obtained using Grindamyl CA 150 during the extraction process. These results suggest that enzymatic treatment is an interesting alternative for producing antioxidant extracts from DT.


Assuntos
Antioxidantes/isolamento & purificação , Celulase/química , Fracionamento Químico/métodos , Extratos Vegetais/isolamento & purificação , Poligalacturonase/química , Thymus (Planta)/química , Antioxidantes/química , Fracionamento Químico/instrumentação , Extratos Vegetais/química
8.
Arch. med. deporte ; 23(112): 101-108, mar.-abr. 2006. ilus, tab
Artigo em Es | IBECS | ID: ibc-044439

RESUMO

El objeto de este trabajo es analizar el efecto del ascenso súbito a una altura moderada sobre la mecánica muscular en distintos niveles de sobrecarga. Para ello, 5 varones deportistas, participaron en este estudio. Utilizando el ejercicio de sentadilla a 900 con barra libre, los participantes ejecutaron una curva de fuerza-velocidad, a partir de la cual se determinó la potencia máxima con un dinamómetro electrónico. En una jornada diferente se realizó una sesión de entrenamiento de fuerza con el método de 10x10, con elmismoejercicio y con la carga asociada a la potencia máxima.Ambos test se ejecutaron en condiciones de normoxia(N) (690m) y de hipoxia (H) súbita moderada(232Om).La potencia desarrollada, la velocidad de desplazamientode la sobrecarga y la percepción de esfuerzo diferenciadafueron registradas. La potencia máxima alcanzaday la carga a la que se obtuvo fueron significativamentesuperiores en H que en N(9l6,64+/-146,14 vs 823,85+/-118,38W y 110,00+/-12,24104,00+/-11,40Kg respectivamente)(p<0,05). La sesión de fuerza no mostró un efecto significativo de la hipoxia en las variables analizadas, a excepción de la percepción de esfuerzo local, la cual se mostró significativamente reducida en altitud (12,98+/-0,44 vs 11,54+/-0,46 para N e H respectivamente)(p<0,05). Por tanto, sobre la base de los resultados obtenidos y, siendo conscientes de las limitaciones ocasionadas por el tamaño de la muestra empleada, podemos concluir que la exposición a una altura moderada parece mejorar la potencia máxima y la carga a la que se localizaron respecto a la generada a nivel del mar. Tanto la hipoxia, como los cambios en la densidad del aire generados con el ascenso, podrían favorecer el reclutamiento selectivo de fibras de perfil mono-funcional anaeróbico en acciones muscularesde corta duración, justificando éste resultado. La fatigagenerada por la acumulación de repeticiones en lasesión podría enmascarar el efecto "facilitador" de la altura en la aplicación de fuerza a gran velocidad, pudiendo ser necesario en tales casos, acortar el volumen de las series


The aim of this study is to analyze the effect of acute ascent to moderate altitude on muscular mechanisms using different levels of resistance. Five healthy athletes participated in this study. Using back squat 90º flexion with free weights, participants executed a force-velocity curve to determine maximum power. On a different day a strength workout (10xl0) was performed with the same exercise using a maximum power load. Both tests were carried out in normoxia (690m) as well as in hypoxia (2320m). Power, speed and the diferenciated Ratings of Perceived Exertion (RPE) were recorded. Maximum power and the maximum power load, were significantly higher in hypoxia than innormoxia (916.64+/-146.14 vs 823.85+/-118.38 W and 110.00+/-12.24 vs 104.00+/-11.40 Kg respectively) (p<0.05).The variables analyzed in the strength workout didn't show any significant difference between normoxia and hypoxia, with the exception of fue local RPE which was reduced in hypoxic conditions (12.98+/-0.44 vs 11.54+/-0.46)( p<0.05). Therefore, based on fuese results, and taking into consideration the limits of the sample size, we can conclude that exposure to moderate alititude seems to improve maximum power and the maximum power load with respect to sea level. Hypoxia, as well as the changes in air density with ascent to a higher altitude, favour the selective recruitment of anaerobic morfo-functional fibers in short muscular action, justifying this result. The fatigue generated after repetitions in the workout could mask the "facilitator" effect of altitude in the application of strength in high speed movements. In fuese cases it could be necessary to reduce the number of sets


Assuntos
Masculino , Adulto , Humanos , Montanhismo/fisiologia , Montanhismo/tendências , Esforço Físico/fisiologia , Educação Física e Treinamento/métodos , Resistência Física/fisiologia , Potência/estatística & dados numéricos , Tono Muscular/fisiologia
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