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Repeated sprint and change-of-direction abilities in soccer players: effects of age group
No full textThe purpose of the present study was to compare the performance in repeated sprint ability (RSA) and repeated changes-of-direction (RCOD) among elite soccer players with different age categories. Forty-nine elite soccer players from the same club and from different age categories (Pro2: n = 8, U19: n = 18, U17: n = 13, and U15: n = 10) participated in this study. Each player was tested in both a RSA straight-line sprints (10 x 20 m with active recovery) and a RCOD test including four 100[degrees] COD at every 4 m (10 x 20 m with active recovery). The average time (AT), fastest time (FT), total time (TT), percentage of decrement score (%Dec), and RSA/RCOD index were recorded and calculated during all the RSA and RCOD tests. Results showed significant age group effects on RSA and RCOD parameters (p \u3c 0.01) and RSA/RCOD index parameters (p \u3c 0.01). Compared with other groups, U15 has significant (p \u3c 0.05) higher values in RSA-AT, RSA-FT, RSA-TT, RCOD-AT, RCOD-FT, RCOD-TT, index-AT, index-FT, and index-TT. However, the trend of performance time and RSA/RCOD index was always similar (i.e., U15 \u3e U17 \u3e U19 \u3e Pro2; Pro2 \u3e U19 \u3e U17 \u3e U15) showing an age dependant for RSA and RCOD performance. The %Dec in RSA of U15 and U17 was significantly (p \u3c 0.05) higher than U19 and Pro2, whereas the %Dec in RCOD of U15 was significantly (p \u3c 0.05) higher than U19. In conclusion, the present study showed that the RSA and RCOD are age dependent, and therefore, coaches should plan a specific program differentiating the RSA and RCOD, while the individualized training could begin in U17
Effects of Ramadan on the diurnal variations of repeated-sprint performance
No full textPurpose: This study examined the effects of Ramadan on cycling repeated-sprint ability (RSA) and corre-sponding diurnal variations.
Methods: Twelve active men performed an RSA test (5 × 6-s maximal sprints interspersed with 24 s passive recovery) during morning and afternoon sessions 1 wk before Ramadan (BR), during the second (R2) and the fourth (R4) weeks of Ramadan, and 2 wk after Ramadan (AR). Maximal voluntary contraction was assessed before (MVCpre), immediately after (MVCpost), and 5 min after the RSA test (MVCpost5). Moreover, hematocrit, hemoglobin, and plasma sodium and potassium (K+) concentrations were measured at rest and after the RSA test and MVCpost.
Results: Overall, peak power (Ppeak) during the RSA test decreased throughout the 5 sprints. Ppeak measured in the rst sprint and MVCpre were lower during Ramadan than BR in the afternoon (P \u3c .05) and higher in the afternoon than the morning BR and AR (P \u3c .05). However, this diurnal rhythmicity was not found for the last 4 sprints’ Ppeak, MVCpost, and MVCpost5 in all testing periods. Furthermore, the last 4 sprints’ Ppeak, MVCpost, MVCpost5, and morning MVCpre were not affected by Ramadan. [K+] measured at rest and after the RSA test and MVCpost were higher during Ramadan than BR in the afternoon (P \u3c .05) and higher in the afternoon than the morning during Ramadan (P \u3c .05).
Conclusions: Fatigability is higher in the afternoon during Ramadan, and, therefore, training and competition should be scheduled at the time of day when physical performance is less affected
Emodin induces cytotoxic effect in human breast carcinoma MCF-7 cell through modulating the expression of apoptosis-related genes
No full textContext: The poor prognostic outcome of breast cancer is largely due to its resistance to cancer therapies. Development of therapeutic agents that can inhibit growth and induce apoptosis in breast cancer cells can help solve the problem. Emodin is an active anthraquinone that has been reported to have diverse biological effects.
Objective: In this study, the anticancer effects of emodin on growth inhibition, apoptosis induction and the expression of apoptosis-related genes in MCF-7 cells were investigated.
Materials and Methods: Growth inhibition induced by emodin was investigated by the MTS assay and the colony formation assay; while emodin-induced apoptosis was determined by the COMET assay and DNA fragmentation detection. Emodin (35 μM)-induced alterations in the expression of apoptotic-related genes were detected by using real-time PCR.
Results: Emodin had significant growth inhibitory effects on MCF-7 cells with IC50 = 7.22 µg/ml (∼30 μM). It also exerted a concentration-dependant inhibitory effect on the colony-forming ability of MCF-7 cells with IC50 = 7.60 µg/ml (∼30 µM). Hallmarks of apoptosis, such as single-strand DNA breakage and DNA fragmentation, were observed in emodin-treated MCF-7 cells. The gene expression of Fas ligand (FASL) was up-regulated (p \u3c 0.01) but those of MCL1, CCND1 and C-MYC were down-regulated (p \u3c 0.05) in emodin-treated MCF-7 cells.
Discussion and Conclusion: This study indicated that emodin could induce growth inhibition and apoptosis in MCF-7 cells through the modulation of the expression of apoptosis-related genes. The growth inhibitory effects of emodin might involve both the intrinsic and the extrinsic apoptotic pathways and cell cycle arrest
pH, ionic strength and dissolved organic matter alter aggregation of fullerene C60 nanoparticles suspensions in wastewater
No full textThe rapid increase in the production and use of fullerene C60 nanoparticles raise concerns about environmental risks and human health. Wastewater treatment plants are key barriers to their discharge into the environment. The aggregation behavior of aqueous suspensions of C60 nanoparticles (nC60) could affect their transport, bioavailability, and removal during wastewater treatment. We tested the aggregation of nC60 in wastewater at different values of pH, ionic strength, and dissolved organic matter (DOM). The nC60 remained relatively stable in filtered wastewater under environmentally relevant conditions up to 24h. But at pH 3 or at high ionic strength (\u3e100mM NaCl), the aggregate size increased greatly, reaching micrometer scale after only 1h. However, the aggregation behavior varied among wastewater samples even at values of similar zeta potential, compared with that in filtered secondary effluent and aeration tank liquor, that in filtered primary effluent was obviously inhibited. This inhibition could be attributed to the steric stabilization due to the adsorption of DOM on nC60 aggregate in addition to electrostatic stabilization. The aggregation results also suggest that membrane filtration could be improved by adjustments to pH
Ecological risk of estrogenic endocrine disrupting chemicals in sewage plant effluent and reclaimed water
No full textThe long-term ecological risk of micropollutants, especially endocrine disrupting chemicals (EDCs) has threatened reclaimed water quality. In this study, estrogenic activity and ecological risk of eight typical estrogenic EDCs in effluents from sewage plants were evaluated. The estrogenic activity analysis showed that steroidal estrogens had the highest estrogenic activity (ranged from 10−1 to 103 ng-E2/L), phenolic compounds showed weaker estrogenic activity (mainly ranged from 10−3 to 10 ng-E2/L), and phthalate esters were negligible. The ecological risk of the estrogenic EDCs which was characterized by risk quotient ranged from 10−4 to 103, with an order in descending: steroids estrogens, phenolic compounds and phthalate esters. The eight estrogenic EDCs were scored and sorted based on the comparison of the estrogenic activity and the ecological risk, suggesting that 17α-ethynylestradiol (EE2), estrone (E1) and estradiol (E2) should be the priority EDCs to control in municipal sewage plants. The results suggested that 17α-ethynylestradiol (EE2), estrone (E1) and estradiol (E2) should be the priority EDCs to control in municipal sewage plants
A review of the phytochemistry and pharmacological activities of raphani semen
No full textThe dried ripe seed of Raphanus sativus L., commonly known as radish seed (or Raphani Semen), is used as traditional Chinese medicine (TCM) to treat constipation, chronic tracheitis, and hypertension. The major active compounds in Raphani Semen are alkaloids, glucosinolates, brassinosteroids, and flavonoids. Fatty acids are its main nutritional contents. Raphani Semen has been demonstrated to have beneficial effects on hypertension, obesity, diabetes mellitus, constipation, and cough. So far, there is no report about the adverse/toxic effects of this herb on humans. However, Raphani Semen processed by roasting was reported to exhibit some adverse effects on mice. Additionally, erucic acid, the main fatty acid in Raphani Semen, was shown to enhance the toxicity of doxorubicin. Thus, Raphani Semen has a potential risk of causing toxicity and drug interaction. In summary, Raphani Semen is a valuable TCM herb with multiple pharmacological effects. More studies on Raphani Semen could help better understand its pharmacological mechanisms so as to provide clear scientific evidence to explain its traditional uses, to identify its therapeutic potential on other diseases, and to understand its possible harmful effects
最高明的中醫就是您自己: 防癌湯水篇
No full text治癌離不開放療或化療，但癌腫引發之痛苦、治療副作用之煎熬，足夠叫病者筋疲力竭，癌魔仍未被打敗，鬥志已經消磨了一大半。由IVE（柴灣）應用科學系高級講師關德祺博士撰寫的新書中，為抗癌病人提供超過30款湯水，幫助減輕化療的副作用，亦提供一些按體質分型的湯譜，以提升免疫力，減低癌病復發風險。儘管癌症機理尚未明確，但肯定與我們的日常生活習慣及身處環境有關，本書亦會指出一些在日常生活中的致癌因素，提醒讀者小心防備
Kinetic models for ultrasound-assisted extraction of water-soluble components and polysaccharides from medicinal fungi
No full textThe aim of this study was to evaluate the suitable kinetic models for ultrasound-assisted extraction (UAE) of water-soluble constituents and polysaccharides from medicinal fungi. The fungal materials chosen for the study included several important edible/medicinal fungi in both mushroom fruit body and mycelial form. The UAE was performed of powdered fungal material in water at a fixed power and a temperature below 50 °C. The experimental data (extract yields versus time) were fitted to several kinetic models by linear regression. The total extract yields from the two mushrooms exhibited a close fit to the power law, Weibull’s exponential, and Elovich’s logarithmic model, and that from the fungal mycelia to the parabolic diffusion model. The polysaccharide yields isolated from the mycelial extracts also fitted closely to the parabolic model, but those from the mushroom extracts did not fit well to any of the kinetic models. The results suggested that the UAE kinetics was dependent on the biological form of fungal material and the aggregation/dispersion of solid particles in the extracting solvent. Ultrasound significantly enhanced the extraction of polysaccharides from the fungi without changing their molecular weight profiles