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991.
Marabotti A Ausili A Staiano M Scirè A Tanfani F Parracino A Varriale A Rossi M D'Auria S 《Biochemistry》2006,45(39):11885-11894
The effect of the pressure on the structure and stability of the D-galactose/D-glucose binding protein from Escherichia coli in the absence (GGBP) and in the presence (GGBP/Glc) of glucose was studied by Fourier transform infrared (FT-IR) spectroscopy and molecular dynamic (MD) simulations. FT-IR spectroscopy experiments showed that the protein beta-structures are more resistant than alpha-helices structures to pressure value increases. In addition, the infrared data indicated that the binding of glucose stabilizes the protein structure against high pressure values, and the protein structure does not completely unfold up to pressure values close to 9000 bar. MD simulations allow a prediction of the most probable configuration of the protein, consistent with the increasing pressures on the two systems. The detailed analysis of the structures at molecular level confirms that, among secondary structures, alpha-helices are more sensitive than beta-structures to the destabilizing effect of high pressure and that glucose is able to preserve the structure of the protein in the complex. Moreover, the evidence of the different resistance of the two domains of this protein to high pressure is investigated and explained at a molecular level, indicating the importance of aromatic amino acid in protein stabilization. 相似文献
992.
da Silva Fernando Henrique Alves de Morais Patrícia Lígia Dantas da Silva Dias Nildo de Sousa Nunes Glauber Henrique de Morais Marciana Bizerra Melo Marlenildo Ferreira de Albuquerque Nascimento Maria Tereza 《Journal of Plant Growth Regulation》2021,40(3):1298-1314
Journal of Plant Growth Regulation - This study evaluated the effect of saline water irrigation (4.5 dS m−1) on growth, gas exchange and mineral nutrient content in eight melon accessions and... 相似文献
993.
Vanderley Rayane F. Ger Kemal A. Becker Vanessa Bezerra Maria Gabriela T. A. Panosso Renata 《Hydrobiologia》2021,848(4):943-960
Hydrobiologia - While warming and eutrophication have increased the frequency and magnitude of harmful cyanobacterial blooms globally, the scenario for many eutrophic tropical freshwaters is a... 相似文献
994.
Chemical Composition,Enantiomeric Analysis,AEDA Sensorial Evaluation and Antifungal Activity of the Essential Oil from the Ecuadorian Plant Lepechinia mutica Benth (Lamiaceae) 下载免费PDF全文
Jorge Ramírez Gianluca Gilardoni Miriam Jácome José Montesinos Marinella Rodolfi Maria Lidia Guglielminetti Cecila Cagliero Carlo Bicchi Giovanni Vidari 《化学与生物多样性》2017,14(12)
This study describes the GC‐FID, GC/MS, GC‐O, and enantioselective GC analysis of the essential oil hydrodistilled from leaves of Lepechinica mutica (Lamiaceae), collected in Ecuador. GC‐FID and GC/MS analyses allowed the characterization and quantification of 79 components, representing 97.3% of the total sample. Sesquiterpene hydrocarbons (38.50%) and monoterpene hydrocarbons (30.59%) were found to be the most abundant volatiles, while oxygenated sesquiterpenes (16.20%) and oxygenated monoterpenes (2.10%) were the minor components. In order to better characterize the oil aroma, the most important odorants, from the sensorial point of view, were identified by Aroma Extract Dilution Analysis (AEDA) GC‐O. They were α‐Pinene, β‐Phellandrene, and Dauca‐5,8‐diene, exhibiting the characteristic woody, herbaceus, and earthy odors, respectively. Enantioselective GC analysis of L. mutica essential oil revealed the presence of twelve couples and two enantiomerically pure chiral monoterpenoids. Their enantiomeric excesses were from a few percent units to 100%. Moreover, the essential oil exhibited moderate in vitro activity against five fungal strains, being especially effective against M. canis, which is a severe zoophilic dermatophyte causal agent of pet and human infections. 相似文献
995.
Anti‐Inflammatory and Antioxidant Actions of Copaiba Oil Are Related to Liver Cell Modifications in Arthritic Rats 下载免费PDF全文
996.
FOXM1 Transcription Factor: A New Component of Chronic Myeloid Leukemia Stem Cell Proliferation Advantage 下载免费PDF全文
Manuela Mancini Fausto Castagnetti Simona Soverini Elisa Leo Caterina De Benedittis Gabriele Gugliotta Gianantonio Rosti Luana Bavaro Sara De Santis Cecilia Monaldi Margherita Martelli Maria Alessandra Santucci Michele Cavo Giovanni Martinelli 《Journal of cellular biochemistry》2017,118(11):3968-3975
997.
Alice Toso Simona Schifano Charlotte Oxborough Krista McGrath Luke Spindler Anabela Castro Lucy Evangelista Vanessa Filipe Maria José Gonçalves Antonio Marques Inês Mendes da Silva Raquel Santos Maria João Valente Iona McCleery Michelle Alexander 《American journal of physical anthropology》2021,176(2):208-222
998.
We investigated usability of mobile computers and field guide books with adult botanical novices, for the identification of wildflowers and deciduous trees in winter. Identification accuracy was significantly higher for wildflowers using a mobile computer app than field guide books but significantly lower for deciduous trees. User preference followed a similar pattern. These results suggest that the identification method and its design are more important for a field guide than its presentation medium (electronic or printed). We discuss the relative advantages of the presentation media used and their value as engagement tools for botany. 相似文献
999.
Aline Cruz Zacarias Maria Andrea Barbosa Renata Guerra-Sá Uberdan Guilherme Mendes De Castro Frank Silva Bezerra Wanderson Geraldo de Lima 《Redox report : communications in free radical research》2017,22(6):515-523
Oxidative stress, physical inactivity and high-fat (FAT) diets are associated with hepatic disorders such as metabolic syndrome (MS). The therapeutic effects of physical training (PT) were evaluated in rats with MS induced by FAT diet for 13 weeks, on oxidative stress and insulin signaling in the liver, during the last 6 weeks. FAT-sedentary (SED) rats increased body mass, retroperitoneal fat, mean arterial pressure (MAP) and heart rate (HR), and total cholesterol, serum alanine aminotransferase, glucose and insulin. Livers of FAT-SED rats increased superoxide dismutase activity, thiobarbituric acid-reactive substances, protein carbonyl and oxidized glutathione (GSSG); and decreased catalase activity, reduced glutathione/GSSG ratio, and the mRNA expression of insulin receptor substrate 1 (IRS-1) and serine/threonine kinase 2. FAT-PT rats improved in fitness and reduced their body mass, retroperitoneal fat, and glucose, insulin, total cholesterol, MAP and HR; and their livers increased superoxide dismutase and catalase activities, the reduced glutathione/GSSG ratio and the expression of peroxisome proliferator-activated receptor gamma and insulin receptor compared to FAT-SED rats. These findings indicated adaptive responses to PT by restoring the oxidative balance and insulin signaling in the liver and certain biometric and biochemical parameters as well as MAP in MS rats. 相似文献
1000.
Tropical soils degraded by slash‐and‐burn cultivation can be recultivated when amended with ashes and compost 下载免费PDF全文
Justine Marie Gay‐des‐Combes Clara Sanz Carrillo Bjorn Jozef Maria Robroek Vincent Eric Jules Jassey Robert Thomas Edmund Mills Muhammad Saleem Arif Leia Falquet Emmanuel Frossard Alexandre Buttler 《Ecology and evolution》2017,7(14):5378-5388
In many tropical regions, slash‐and‐burn agriculture is considered as a driver of deforestation; the forest is converted into agricultural land by cutting and burning the trees. However, the fields are abandoned after few years because of yield decrease and weed invasion. Consequently, new surfaces are regularly cleared from the primary forest. We propose a reclamation strategy for abandoned fields allowing and sustaining re‐cultivation. In the dry region of south‐western Madagascar, we tested, according to a split‐plot design, an alternative selective slash‐and‐burn cultivation technique coupled with compost amendment on 30–year‐old abandoned fields. Corn plants (Zea mays L.) were grown on four different types of soil amendments: no amendment (control), compost, ashes (as in traditional slash‐and‐burn cultivation), and compost + ashes additions. Furthermore, two tree cover treatments were applied: 0% tree cover (as in traditional slash‐and‐burn cultivation) and 50% tree cover (selective slash‐and‐burn). Both corn growth and soil fertility parameters were monitored during the growing season 2015 up to final harvest. The amendment compost + ashes strongly increased corn yield, which was multiplied by 4–5 in comparison with ashes or compost alone, reaching 1.5 t/ha compared to 0.25 and 0.35 t/ha for ashes and compost, respectively. On control plots, yield was negligible as expected on these degraded soils. Structural equation modeling evidenced that compost and ashes were complementary fertilizing pathways promoting soil fertility through positive effects on soil moisture, pH, organic matter, and microbial activity. Concerning the tree cover treatment, yield was reduced on shaded plots (50% tree cover) compared to sunny plots (0% tree cover) for all soil amendments, except ashes. To conclude, our results provide empirical evidence on the potential of recultivating tropical degraded soils with compost and ashes. This would help mitigating deforestation of the primary forest by increasing lifespan of agricultural lands. 相似文献