55 research outputs found

    Prior Low- or High-Intensity Exercise Alters Pacing Strategy, Energy System Contribution and Performance during a 4-km Cycling Time Trial

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    We analyzed the influence of prior exercise designed to reduce predominantly muscle glycogen in either type I or II fibers on pacing and performance during a 4-km cycling time trial (TT). After preliminary and familiarization trials, in a randomized, repeated-measures crossover design, ten amateur cyclists performed: 1) an exercise designed to reduce glycogen of type I muscle fibers, followed by a 4-km TT (EX-FIB I); 2) an exercise designed to reduce glycogen of type II muscle fibers, followed by a 4-km TT (EX-FIB II) and; 3) a 4-km TT, without the prior exercise (CONT). the muscle-glycogen-reducing exercise in both EX-FIB I and EX-FIB II was performed in the evening, similar to 12 h before the 4-km TT. Performance time was increased and power output (PO) was reduced in EX-FIB I (432.8 +/- 8.3 s and 204.9 +/- 10.9 W) and EX-FIB II (428.7 +/- 6.7 s and 207.5 +/- 9.1 W) compared to CONT (420.8 +/- 6.4 s and 218.4 +/- 9.3 W; P0.05). the PO was lower in EX-FIB I than in CONT at the beginning and middle of the trial (P0.05). the integrated electromyography was unchanged between conditions (P>0.05). Performance may have been impaired in EX-FIB I due a more conservative pacing at the beginning and middle, which was associated with a reduced aerobic contribution. in turn, the PO profile adopted in EX-FIB II was also reduced throughout the trial, but the impairment in performance may be attributed to a reduced glycolytic contribution (i.e. reduced lactate accumulation).Foundation of Aids to Scientific Research of the State of Alagoas (FAPEAL)Univ Fed Pernambuco, CAV, Dept Phys Educ & Sports Sci, Sports Sci Res Grp, Vitoria de Santo Antao, Pernambuco, BrazilUniv São Paulo, Sch Phys Educ & Sport, Endurance Performance Res Grp, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, BrazilVictoria Univ, Coll Sport & Exercise Sci, Inst Sport Exercise & Active Living, Melbourne, Vic 8001, AustraliaUniversidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, BrazilWeb of Scienc

    Evaluation of the postharvest quality of Cagaita fruits (Eugenia dysenterica DC.) coated with chitosan and associated with refrigeration

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    Cagaita fruits are subject to seasonality and perishability. This work aims to use scanning electron microscopy (SEM) to evaluate the physicochemical characteristics, texture, color and physical structure of cagaita fruits coated with different chitosan concentrations. The fruits were divided as follows: T0 (uncoated fruits), T1 (fruits coated with 1% (v/v) chitosan), T2 (fruits coated with 2% (v/v) chitosan) and T3 (fruits coated with 3% (v/v) chitosan). They were analyzed at 0, 10, 20 and 30 days of storage. Titratable acidity and soluble solids content showed no conservation of fruit characteristics; they showed better results for uncoated fruits, as well as weight loss, vitamin C and peak strain. The color of cagaita fruits confirmed ripening during storage regardless of treatment. Scanning electron microscopy showed that the film solution did not adhere, as desired, to the cell wall of fruits. As the results of fruits coated with 3% pectin were close to control, further studies should be carried out with higher coating percentages so that the fruit quality is maintained during storage.Keywords: Physical structure, film solution, quality, shelf life

    Possible oxidative effects of isotretinoin and modulatory effects of vitamins A and C in Saccharomyces cerevisiae

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    Isotretinoin (ITN), chemically known as 13-cis-retinoic acid, is a part of the broad group of compounds related to vitamin A. It is particularly employed in the treatment of nodular cystic acne and as an inhibitor of proliferation of neoplastic cells, by exerting a regulatory effect on the cell differentiation. This study aimed at investigating the possible oxidative effects of ITN and modulatory effects of vitamins A and C in mutant and non-mutant Saccharomyces cerevisiae strains. In addition, to reconfirm the oxidative effects, five in vitro antioxidant assays were also prepared taking the alpha-tocopherol analogue, trolox as a standard. In vivo study conducted on S. cerevisiae cells was carried out with ITN 20 μg/ml taking hydrogen peroxide (H2O2) as stressor (STR), whereas ITN 5 to 50 μg/ml was considered for in vitro assays taking similar dose of trolox (TRO). Results show ITN to have oxidative effect in both in vitro and in vivo tests. In conclusion, ITN produced oxidative effects and there may be an hypervitaminosis effect with vitamins A and C, thus insinuation to genetic material.Key words: Assay, isotretinoin, vitamin A, vitamin C, oxidative stress

    Efeitos da estimulação da sucção não nutritiva com dedo enluvado na transição alimentar em recém-nascido prematuro de muito baixo peso

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    Objetivos analisar os efeitos da estimulação da sucção não nutritiva com a técnica do dedo enluvado, sobre o início e a transição alimentar da via gástrica para a via oral em prematuros de muito baixo peso. Métodos estudo aleatório, prospectivo, longitudinal, experimental e controlado, que incluiu 40 prematuros internados na UTI Neonatal do Hospital de Clínicas, com idade gestacional £ 32 semanas e peso de nascimento £ 1500g, clinicamente estáveis. Os prematuros foram distribuídos aleatoriamente, por meio de sorteio, em 2 grupos: grupo controle, sem SNN e grupo experimental, com SNN com dedo enluvado, 3 vezes ao dia, 3 dias na semana. Foram avaliados critérios quanto ao escore da avaliação da prontidão para início da alimentação oral, intercorrências durante a sucção nutritiva (SN) e o tempo de transição alimentar. Resultados quando comparado o grupo experimental em relação ao grupo controle observou-se um escore significantemente maior na avaliação da prontidão para início da alimentação via oral, uma menor frequência de sinais de estresse durante a sucção nutritiva e um menor tempo de transição alimentar da via gástrica para via oral. Conclusão a estimulação da sucção não nutritiva com a técnica do dedo enluvado melhorou a prontidão do prematuro para início da alimentação via oral, diminuiu a frequência dos sinais de estresse durante a alimentação via oral e reduziu o tempo de transição alimentar no grupo experimental quando comparado ao grupo controle

    Correlations between Risk Factors for Breast Cancer and Genetic Instability in Cancer Patients- A Clinical Perspective Study

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Molecular epidemiological studies have identified several risk factors linking to the genes and external factors in the pathogenesis of breast cancer. In this sense, genetic instability caused by DNA damage and DNA repair inefficiencies are important molecular events for the diagnosis and prognosis of therapies. Therefore, the objective of this study was to analyze correlation between sociocultural, occupational, and lifestyle risk factors with levels of genetic instability in non-neoplastic cells of breast cancer patients. Total 150 individuals were included in the study that included 50 breast cancer patients submitted to chemotherapy (QT), 50 breast cancer patients submitted to radiotherapy (RT), and 50 healthy women without any cancer. Cytogenetic biomarkers for apoptosis and DNA damage were evaluated in samples of buccal epithelial and peripheral blood cells through micronuclei and comet assay tests. Elder age patients (61–80 years) had higher levels of apoptosis (catriolysis by karyolysis) and DNA damage at the diagnosis (baseline damage) with increased cell damage during QT and especially during RT. We also reported the increased frequencies of cytogenetic biomarkers in patients who were exposed to ionizing radiation as well as for alcoholism and smoking. QT and RT induced high levels of fragmentation (karyorrhexis) and nuclear dissolution (karyolysis) and DNA damage. Correlations were observed between age and karyorrhexis at diagnosis; smoking and karyolysis during RT; and radiation and karyolysis during QT. These correlations indicate that risk factors may also influence the genetic instability in non-neoplastic cells caused to the patients during cancer therapies
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