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排序方式: 共有221条查询结果,搜索用时 31 毫秒
41.
Hesam Addin Akbari Amine Ghram Mohammad Yoosefi Ross Arena Carl J Lavie Hamdi Chtourou Helmi Ben Saad Karim Chamari 《Biology of sport / Institute of Sport》2021,38(4):729
Intermittent fasting (IF) has recently gained popularity, and has been used for centuries in many religious practices. The Ramadan fasting is a mandatory form of IF practiced by millions of healthy adult Muslims globally for a whole lunar month every year. In Islam, the “Sunna” also encourages Muslims to practice IF all along the year (e.g.; two days a week). The 2019-Coronavirus disease (COVID-19) pandemic in the context of Ramadan has raised the question whether fasting is safe practice during the COVID-19 pandemic health crisis, and what would be the healthy lifestyle behaviors while fasting that would minimize the risk of infection. As COVID-19 lacks a specific therapy, IF and physical activity could help promote human immunity and be part of holistic preventive strategy against COVID-19. In this commentary, the authors focus on this dilemma and provide recommendations to the fasting communities for safely practicing physical activity in time of COVID-19 pandemic. 相似文献
42.
Annarita De Luca Niccol Arena Luigi M. Sena Enzo Medico 《Journal of cellular physiology》1999,180(3):365-371
The proto-oncogene c-MET encodes the tyrosine kinase receptor for hepatocyte growth factor (HGF), a pleiotropic cytokine controlling growth, survival, motility, invasive migration, and differentiation of epithelial cells. Like several other epithelial neoplasms, thyroid carcinomas have been found to overexpress c-MET at both the mRNA and protein level. The biological relevance of Met overexpression to thyroid carcinoma natural history, however, remains to be elucidated. Therefore, we analyzed Met expression and response to HGF in two cell lines established from human thyroid carcinomas. In both lines we observed that the overexpressed and constitutively tyrosine phosphorylated HGF receptor maintained biochemical responsiveness to the ligand. Both cell lines were also found to respond to HGF by consistently increasing their motility and invading in vitro reconstituted basal membranes. Conversely, no effect of HGF could be observed in proliferation and survival assays. These data show that overexpression of Met specifically confers to transformed thyroid cells a motile-invasive phenotype that is dependent on exogenous HGF stimulation. J. Cell. Physiol. 180:365–371, 1999. © 1999 Wiley-Liss, Inc. 相似文献
43.
Alejandro Pablo Arena Roxana Piastrellini Gabriela Nuri Barón Bárbara María Civit 《The International Journal of Life Cycle Assessment》2017,22(4):546-556
Purpose
Many tools to quantify the environmental impact of human decisions have been developed, but all of them seem to have a limited application at the regional or local level. A free-of-charge, Argentina-based personal footprint calculator software (YUPI®) has been developed in order to raise awareness among local citizens about the environmental impacts generated by their daily habits. The extensive use of the tool will generate information suitable for future scientific studies based on local data.Methods
The software calculates the ecological, carbon, and water footprints of individuals, implementing specific regional data from Argentina developed by the CLIOPE group, complemented with data from the Water Footprint Network and the Global Footprint Network. The calculator was developed focusing on interface attractiveness, ease of use, language simplicity, and a good trade-off between completion time and fullness.Results and discussion
The YUPI® software allows its users to understand at a glance their contribution to the environmental impacts of modern society and to quantify the reduction opportunities they have at hand. The program’s language and variables reflect local lifestyle choices, making the filling process accessible for children. The calculator was placed online as an educational tool for teachers and students from all educational levels, and it was also used by visitors in local science and educational fairs. Valuable data was collected for future initiatives on impact mitigation.Conclusions
Amplified by the mass media, the new tool has helped raise awareness and discussion about the individual environmental footprint, both in the educational and in the domestic terrain. The strategy of creating a simple, easily administered, and widely available quiz helped bridge the gap between the academy and the people, making available to them the continuously updated information generated by the research groups. This is facilitating citizen not only to understand the complexity of the environmental problems but also to take informed actions leading to their mitigation.44.
Exploring the chicken egg white proteome with combinatorial peptide ligand libraries 总被引:3,自引:0,他引:3
D'Ambrosio C Arena S Scaloni A Guerrier L Boschetti E Mendieta ME Citterio A Righetti PG 《Journal of proteome research》2008,7(8):3461-3474
The use of two types of peptide ligand libraries (PLL), containing hexapeptides terminating either with a primary amine or modified with a terminal carboxyl group, allowed the discovery and identification of a large number of previously unreported egg white proteins. Whereas the most comprehensive list up to date ( Mann, K. , Proteomics 2007, 7, 3558- 3568 ) tabulated 78 unique gene products, our findings have almost doubled that value to 148 unique protein species. From the initial nontreated egg, it was possible to find 41 protein species; the difference (107 proteins) was generated as a result of the use of PLLs from which a similar number of species (112 and 109, respectively) was evidenced. Of those, 35 proteins were the specific catch of the amino-terminus PLL, while 33 were uniquely captured by the carboxy-terminus PLL. While a number of these low-abundance proteins might have a biological role in maintaining the integrity of the egg white and protecting the yolk, others might be derived from decaying epithelial cells lining the oviduct and/or represent remnants of products from the magnum and eggshell membrane components secreted by the isthmus, which might ultimately be incorporated, even if in trace amounts, into the egg white. The list of egg white components here reported is by far the most comprehensive at present and could serve as a starting point for isolation and functional characterization of proteins possibly having novel pharmaceutical and biomedical applications. 相似文献
45.
Luca Vitale Paul Di Tommasi Carmen Arena Michele Riondino Annachiara Forte Angelo Verlotta Angelo Fierro Amalia Virzo De Santo Amodio Fuggi Vincenzo Magliulo 《Acta Physiologiae Plantarum》2009,31(2):331-341
The effect of water shortage on growth and gas exchange of maize grown on sandy soil (SS) and clay soil was studied. The lower
soil water content in the SS during vegetative growth stages did not affect plant height, above-ground biomass, and leaf area
index (LAI). LAI reduction was observed on the SS during the reproductive stage due to early leaf senescence. Canopy and leaf
gas exchanges, measured by eddy correlation technique and by a portable photosynthetic system, respectively, were affected
by water stress and a greater reduction in net photosynthetic rate (A
N) and stomatal conductance (g
s) was observed on SS. Chlorophyll and carotenoids content was not affected by water shortage in either condition. Results
support two main conclusions: (1) leaf photosynthetic capacity was unaffected by water stress, and (2) maize effectively endured
water shortage during the vegetative growth stage. 相似文献
46.
This work aimed to evaluate if gas exchange and PSII photochemical activity in maize are affected by different irradiance
levels during short-term exposure to elevated CO2. For this purpose gas exchange and chlorophyll a fluorescence were measured on maize plants grown at ambient CO2 concentration (control CO2) and exposed for 4 h to short-term treatments at 800 μmol(CO2) mol−1 (high CO2) at a photosynthetic photon flux density (PPFD) of either 1,000 μmol m−2 s−1 (control light) or 1,900 μmol m−2 s−1 (high light). At control light, high-CO2 leaves showed a significant decrease of net photosynthetic rate (P
N) and a rise in the ratio of intercellular to ambient CO2 concentration (C
i/C
a) and water-use efficiency (WUE) compared to control CO2 leaves. No difference between CO2 concentrations for PSII effective photochemistry (ΦPSII), photochemical quenching (qp) and nonphotochemical quenching (NPQ) was detected. Under high light, high-CO2 leaves did not differ in P
N, C
i/C
a, ΦPSII and NPQ, but showed an increase of WUE. These results suggest that at control light photosynthetic apparatus is negatively
affected by high CO2 concentration in terms of carbon gain by limitations in photosynthetic dark reaction rather than in photochemistry. At high
light, the elevated CO2 concentration did not promote an increase of photosynthesis and photochemistry but only an improvement of water balance due
to increased WUE. 相似文献
47.
L. Vitale P. di Tommasi C. Arena M. Oliva T. Bertolini S. Ranucci A. Virzo de Santo V. Magliulo 《Photosynthetica》2011,49(3):330-338
A mixture of ryegrass (Lolium italicum A. Braun) and clover (Trifolium alexandrinum L.) was sown in Eboli (Salerno, Southern Italy) in September 2007. Crop growth, leaf and canopy gas exchange and ecophysiological
traits were monitored throughout the growth cycle. The gross primary production (GPP) was not affected by air temperature
(T
air); on the contrary the ecosystem respiration (R
eco) decreased as T
air decreased while net ecosystem CO2 exchange (NEE) increased. When was normalized with leaf area index (LAI), GPP decreased with T
air, a likely response to cold that down-regulated canopy photosynthesis in order to optimize the light use at low winter temperatures.
Net photosynthetic rates (P
N), the effective quantum yield of PSII (ΦPSII) and photosynthetic pigment content were higher in clover than ryegrass, in relation to the higher leaf N content. The lower
ΦPSII in ryegrass was linked to lower photochemical quenching coefficient (qP) values, due to a reduced number of reaction centres, in agreement with the lowest Chl a content. This behaviour can be considered as an adaptive strategy to cold to avoid photooxidative damage at low temperature
rather than an impairment of PSII complexes. 相似文献
48.
Arena MP Romano A Capozzi V Beneduce L Ghariani M Grieco F Lucas P Spano G 《Letters in applied microbiology》2011,53(4):395-402
Aims: Lactobacillus brevis IOEB 9809 is able to produce both tyramine and putrescine via tyrosine decarboxylase and agmatine deiminase enzymes, respectively, when cultured on synthetic media. The aims of this study were to assess the expression of L. brevis IOEB 9809 tdc and aguA1 genes, during wine fermentation and to evaluate the effect of substrate availability and pH on tdc and aguA1 expression, as well as on biogenic amine production and L. brevis viability. Methods and Results: The relative expression of L. brevis IOEB 9809 tdc and aguA1 genes was analysed in wine by quantitative real‐time RT‐PCR (qRT‐PCR) during a period of incubation of 30 days. Cell viability, pH values, putrescine and tyramine concentration were monitored throughout the experiments. Conclusions: The wine trials indicated that L. brevis IOEB 9809 is able to produce both tyramine and putrescine during wine fermentation. Increased cell viability was also observed in wine supplemented with tyrosine or agmatine. qRT‐PCR analysis suggests a strong influence of substrate availability on the expression of genes coding for tyrosine decarboxylase and agmatine deiminase in L. brevis IOEB 9809. Less evident is the relationship between putrescine and tyramine production and tolerance to wine pH. Significance and Impact of Study: To our knowledge, this study represents the first assessment of relative expression of L. brevis IOEB 9809 genes involved in biogenic amine production in wine. Furthermore, an effect of biogenic amine production on viability of L. brevis during wine fermentation was established. 相似文献
49.
Mattia P. Arena Pasquale Russo Vittorio Capozzi Paloma López Daniela Fiocco Giuseppe Spano 《Applied microbiology and biotechnology》2014,98(17):7569-7581
The probiotic potential of Lactobacillus plantarum and Lactobacillus fermentum strains, capable of overproducing riboflavin, was investigated. The riboflavin production was quantified in co-cultures of lactobacilli and human intestinal epithelial cells, and the riboflavin overproduction ability was confirmed. When milk and yogurt were used as carrier matrices, L. plantarum and L. fermentum strains displayed a significant ability to survive through simulated gastrointestinal transit. Adhesion was studied on both biotic and abiotic surfaces. Both strains adhered strongly on Caco-2 cells, negatively influenced the adhesion of Escherichia coli O157:H7, and strongly inhibited the growth of three reference pathogenic microbial strains. Resistance to major antibiotics and potential hemolytic activity were assayed. Overall, this study reveals that these Lactobacillus stains are endowed with promising probiotic properties and thus are candidates for the development of novel functional food which would be both enriched in riboflavin and induce additional health benefits, including a potential in situ riboflavin production, once the microorganisms colonize the host intestine. 相似文献
50.
Giuseppe Gambino Sara De Pinto Lorenzo Tei Claudio Cassino Francesca Arena Eliana Gianolio Mauro Botta 《Journal of biological inorganic chemistry》2014,19(2):133-143
A dimeric GdAAZTA-like complex (AAZTA is 6-amino-6-methylperhydro-1,4-diazepinetetraacetic acid) bearing an adamantyl group (Gd2 L1) able to form strong supramolecular adducts with specific hosts such as β-cyclodextrin (β-CD), poly-β-CD, and human serum albumin (HSA) is reported. The relaxometric properties of Gd2 L1 were investigated in aqueous solution by measuring the 1H relaxivity as a function of pH, temperature, and magnetic field strength. The relaxivity of Gd2 L1 (per Gd atom) at 40 MHz and 298 K is 17.6 mM?1 s?1, a value that remains almost constant at higher fields owing to the great compactness and rigidity of the bimetallic chelate, resulting in an ideal value for the rotational correlation time for high-field MRI applications (1.5–3.0 T). The noncovalent interaction of Gd2 L1 with β-CD, poly-β-CD, and HSA and the relaxometric properties of the resulting host–guest adducts were investigated using 1H relaxometric methods. Relaxivity enhancements of 29 and 108 % were found for Gd2 L1–β-CD and Gd2 L1–poly-β-CD, respectively. Binding of Gd2 L1 to HSA (K A = 1.2 × 104 M?1) results in a remarkable relaxivity of 41.4 mM?1 s?1 for the bound form (+248 %). The relaxivity is only limited by the local rotation of the complex within the binding site, which decreases on passing from Gd2 L1–β-CD to Gd2 L1–HSA. Finally, the applicability of Gd2 L1 as tumor-targeting agent through passive accumulation of the HSA-bound adduct was evaluated via acquisition of magnetic resonance images at 1 T of B16-tumor-bearing mice. These experiments indicate a considerable signal enhancement (+160 %) in tumor after 60 min from the injection and a very low hepatic accumulation. 相似文献