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1.
Sci Rep ; 14(1): 6261, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491131

RESUMO

Terahertz imaging is unlocking unique capabilities for the analysis of cultural heritage artifacts. This paper uses terahertz time-domain imaging for the study of a gilded wooden artifact, providing a means to perform stratigraphic analysis, yielding information about the composition of the artifact, presence of certain materials identifiable through their THz spectral fingerprint, as well as alterations that have been performed over time. Due to the limited information that is available for many historic artifacts, the data that can be obtained through the presented technique can guide proper stewardship of the artifact, informing its long-term preservation.

2.
Antioxidants (Basel) ; 8(2)2019 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-30691231

RESUMO

Antioxidant activity of native vitamin C (ascorbic acid, AH2) is hampered by instability in solution. Selective loading of AH2 into the inner lumen of natural halloysite nanotubes (HNT) yields a composite nanoantioxidant (HNT/AH2), which was characterized and investigated for its reactivity with the persistent 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical and with transient peroxyl radicals in the inhibited autoxidation of organic substrates, both in organic solution (acetonitrile) and in buffered (pH 7.4) water in comparison with native AH2. HNT/AH2 showed excellent antioxidant performance being more effective than native ascorbic acid by 131% in acetonitrile and 290% (three-fold) in aqueous solution, under identical settings. Reaction with peroxyl radicals has a rate constant of 1.4 × 106 M-1 s-1 and 5.1 × 104 M-1 s-1, respectively, in buffered water (pH 7.4) and acetonitrile, at 30 °C. Results offer physical understanding of the factors governing HNT/AH2 reactivity. Improved performance of HNT/AH2 is unprecedented among forms of stabilized ascorbic acid and its relevance is discussed on kinetic grounds.

3.
J Aging Phys Act ; 22(4): 482-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24084003

RESUMO

PURPOSE: High-intensity aerobic interval training (AIT) has been reported to be more effective than continuous aerobic training (CoAT) to improve metabolic health. The aim of our study was to investigate whether moderate-intensity AIT is more effective than CoAT on metabolic health when applied to a walking training program. DESIGN/METHODS: Thirty-two postmenopausal women (55.37 ± 3.46 years) were investigated for body composition, plasma glucose, insulin, lipids, adiponectin, HOMA-IR, HOMA-AD, aerobic fitness, dietary habits, and spontaneous physical activity, and randomly assigned to one of two different walking training programs: CoAT or AIT. RESULTS: CoAT and AIT elicited the same physiological benefits, including: reduction of plasma glucose, insulin, HOMA-IR and HOMA-AD, and increase of plasma HDL-C, adiponectin, and aerobic fitness. CONCLUSIONS: An AIT scheme as part of an outdoor walking training program elicits the same physiological adaptations as a CoAT scheme, probably because walking does not promote exercise intensities that elicit greater effects.


Assuntos
Educação/métodos , Aptidão Física/fisiologia , Pós-Menopausa/metabolismo , Caminhada/fisiologia , Adaptação Fisiológica , Composição Corporal , Índice de Massa Corporal , HDL-Colesterol/sangue , Feminino , Humanos , Insulina/sangue , Pessoa de Meia-Idade , Resultado do Tratamento
4.
Menopause ; 20(4): 455-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23250080

RESUMO

OBJECTIVE: We hypothesized that physical exercise in postmenopausal women could interfere with the molecular interrelationship of the immune-endocrine system and be effective even in women in whom training determined a reduction of spontaneous physical activity (SPA). For this reason, we investigated the effects of an aerobic program on plasma dehydroepiandrosterone sulfate (DHEA-S) and cytokine levels in relationship to SPA modification. METHODS: Thirty-two postmenopausal women (mean [SD] age, 56.38 [4.33] y) were enrolled in the study. Inclusion criteria were as follows: age younger than 65 years, body mass index higher than 18.5 and lower than 35 kg/m2, no pharmacological treatments, and no history of chronic, cardiovascular, or orthopedic diseases. Before and after 3 months of walking training at moderate intensity (40-50 min, 4 d/wk), they were evaluated for SPA, body composition, energy intake, and levels of plasma cytokines (tumor necrosis factor α [TNF-α], interleukin [IL]-1α, IL-1ß, IL-2, IL-8, and IL-10), C-reactive protein, DHEA-S, cortisol, and estrogen. RESULTS: At baseline, SPA did not correlate with either DHEA-S level or cytokine levels. There was negative correlation between DHEA-S and both TNF-α and IL-2. After the intervention program, 16 women showed increased SPA, and 16 women showed decreased SPA. Independent of these changes in SPA, both TNF-α levels and cortisol-to-DHEA-S ratio decreased, whereas DHEA-S levels increased. CONCLUSIONS: In postmenopausal women, walking training, rather than SPA, influences DHEA-S and cytokine concentrations and their correlations, thus interfering with adrenal steroids and the inflammatory markers network. Physical exercise acts in parallel on menopausal neuroendocrine alterations and on the systemic inflammatory profile independent of SPA changes.


Assuntos
Citocinas/sangue , Sulfato de Desidroepiandrosterona/sangue , Inflamação/sangue , Atividade Motora/fisiologia , Pós-Menopausa , Caminhada/fisiologia , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Proteína C-Reativa/análise , Ingestão de Energia , Estrogênios/sangue , Exercício Físico/fisiologia , Feminino , Humanos , Hidrocortisona/sangue , Pessoa de Meia-Idade
5.
Menopause ; 19(1): 23-32, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21993080

RESUMO

OBJECTIVE: Because physical exercise has been widely used for primary and secondary preventions of cardiometabolic diseases arising with menopause, the aim of our study was to determine whether participation in aerobic physical exercise is linked to the modification of spontaneous physical activity and whether this compensation affects aerobic training-related body adaptations. METHODS: Both before and after a 13-week walking training program, 34 postmenopausal women (mean ± SD age, 55.89 ± 3.57 y) were analyzed for lipids, adipokines, glucose, and insulin plasma levels, as well as for body measures, heart rate and blood pressure at rest, maximal aerobic capacity, total daily energy expenditure, mean intensity of daily physical activities, and time and energy spent on physical activities with an intensity of more than three metabolic equivalents. RESULTS: Aerobic training induced significant reductions in body mass, body mass index, heart rate, systolic blood pressure, basal cardiac double product, plasma glucose, leptin, and resistin. Aerobic fitness, the reserve of the cardiac double product, and the quantitative insulin sensitivity index were significantly improved. Cluster analysis of the variations in the total daily energy expenditure, the mean intensity of daily physical activities, and the time and energy spent on physical activities with an intensity of more than three metabolic equivalents identified two subgroups: one showed reduced spontaneous physical activity (GROUP-), whereas the other did not (GROUP+). The subgroups differed significantly only for plasma lipid variation. GROUP+ showed significantly reduced low-density lipoprotein cholesterol and total cholesterol, whereas GROUP- did not show significantly modified plasma lipids. CONCLUSIONS: In postmenopause, participation in a program of aerobic physical exercise can result in a reduction of spontaneous physical activity, which inhibits the positive effects of the aerobic exercise on plasma lipids and lipoproteins.


Assuntos
Pós-Menopausa/fisiologia , Caminhada/fisiologia , Glicemia/análise , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Ingestão de Energia , Metabolismo Energético , Exercício Físico/fisiologia , Comportamento Alimentar , Feminino , Frequência Cardíaca , Humanos , Resistência à Insulina , Leptina/sangue , Lipídeos/sangue , Pessoa de Meia-Idade , Aptidão Física , Resistina/sangue
6.
Clin Endocrinol (Oxf) ; 75(6): 747-52, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21671973

RESUMO

INTRODUCTION: Several studies have shown that activation of the sympathetic nervous system results in the increased secretion of α-amylase (sAA), an enzyme produced by salivary glands. Recently, chromogranin A (CgA), a soluble protein costored and coreleased with catecholamines from the adrenal medulla and sympathetic nerve endings, has been proposed as a marker of sympathoadrenal medullary system (SAM) activity. The aim of this study was to investigate the behaviour of salivary chromogranin A (sCgA) and sAA during high-intensity exercise and to analyse their possible correlation with cardiovascular and psychological parameters. METHODS: Before and during a standardized treadmill stress test, and at 5, 15 and 30 min during the recovery phase, sCgA and sAA were monitored in 21 healthy men. The double product (DP) of blood pressure and heart rate responses, and the product of the subjective ratings of perceived exertion recorded at the final step (RPE) and the exercise duration were used as indices of cardiovascular and exercise intensity, respectively. RESULTS: With respect to baseline, significant (P < 0·001) increases in peak sCgA (median 64%) and sAA (median 86%) were observed at the end of exercise. During the recovery phase, sAA levels fell abruptly, whereas sCgA remained elevated (P < 0·001). Significant correlations emerged only for sCgA with respect to %DP (r = 0·84; P < 0·001) and last step-RPE (r = 0·82; P = 0·024). CONCLUSIONS: These data suggest sCgA as a reliable marker of SAM activation. Furthermore, the relationship between sCgA and exercise intensity highlights the potential use of this noninvasive parameter in monitoring the adrenergic response during intense physical stress.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Cromogranina A/metabolismo , Exercício Físico/fisiologia , Saliva/metabolismo , alfa-Amilases/metabolismo , Adulto , Sistema Cardiovascular/metabolismo , Cromogranina A/análise , Teste de Esforço , Humanos , Masculino , Esforço Físico/fisiologia , Saliva/química , Saliva/enzimologia , Manejo de Espécimes , Adulto Jovem , alfa-Amilases/análise
7.
J Sports Sci Med ; 8(3): 401-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-24150004

RESUMO

Pre-participation screening is very important for prescribing and practising exercise safely. The aim of this study was to investigate both ratings of perceived exertion (RPE) and blood pressure responses in two different types of exercises with matching duration and indirectly determined working heart rate (HR). Participants were 23 male students, who were generally healthy but sedentary. The time course of their RPE and blood pressure during a 50- minute work-out session on an arm crank ergometer and a cross trainer were compared. RM-ANOVA showed both a higher RPE (p < 0.001) and diastolic blood pressure (DBP) (p < 0.001) response to the arm exercise that were shown significantly correlated (r = 0.883; p = 0.008). Linear regression analysis (p = 0.001) confirmed the ability to predict the time course of DBP by knowing the RPE on the arm crank ergometer. Even if people use the recommended relative intensity, the HR method is not always safe for health without pre-participation screening because exercise characteristics can negatively influence physiological responses. The HR method could be substituted by the RPE method. Key pointsArm Crank Ergometer elicits a higher diastolic blood pressure response respect to Cross Trainer when people exercise at the same heart rate.Arm Crank Ergometer elicits a higher ratings of perceived exertion respect to Cross trainer when people exercise at the same heart rate.Indirect determined working heart rate is not always safe even if the theoretical intensity is that recommended for health.Rating of perceived exertion method should be used instead of heart rate method to avoid the dangerous physiological responses observed.

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