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251.
To expand the potential of pseudopterosins and seco-pseudopterosins isolated from the octocoral Pseudopterogorgia elisabethae of San Andrés and Providencia islands (southwest Caribbean Sea), we report the anti-microbial profile against four pathogenic microorganisms (Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans) and report a more complete cytotoxic profile against five human cells lines (HeLa, PC-3, HCT116, MCF-7 and BJ) for the compounds PsG, PsP, PsQ, PsS, PsT, PsU, 3-O-acetyl-PsU, seco-PsJ, seco-PsK and IMNGD. For the cytotoxic profiles, all compounds evaluated showed moderate and non-selective activity against both tumor and normal cell lines, where PsQ and PsG were the most active compounds (GI50 values between 5.8 μM to 12.0 μM). With respect to their anti-microbial activity the compounds showed good and selective activity against the Gram-positive bacteria, while they did not show activity against the Gram-negative bacterium or yeast. PsU, PsQ, PsS, seco-PsK and PsG were the most active compounds (IC50 2.9–4.5 μM) against S. aureus and PsG, PsU and seco-PsK showed good activity (IC50 3.1–3.8 μM) against E. faecalis, comparable to the reference drug vancomycin (4.2 μM). 相似文献
252.
Fabio Gresta Giovanni Avola Emidio Albertini Lorenzo Raggi Valerio Abbate 《Genetic Resources and Crop Evolution》2010,57(4):523-531
In this paper molecular analysis, physical, technological, and chemical traits were used to estimate the level of variation
on five accessions of a locally adapted Sicilian faba bean (Vicia faba L.) landrace named ‘Larga di Leonforte’. DNA analysis was performed using the Amplified Fragment Length Polymorphism (AFLP)
molecular marker class and two other faba beans (cv. ‘Aguadulce Samba’—Spain—and landrace ‘Locale di Modica’—Sicily) were
used as controls. Although the accessions of ‘Larga di Leonforte’ varied significantly for most of the agronomical and physical
traits, this landrace generally had a heavy seed weight, short but large pods, and no more than two seeds per pod. This last
characteristic allowed for erect pod angle attitude at maturity. Idratation data showed difference among accessions in seed
weight at full hydration and in absorption rate at the very beginning of the hydration process, while any difference among
accessions emerged in terms of cooking properties. The six AFLP Eco+3/Mse+3 different primer combinations applied in this
research revealed different levels of polymorphism among the faba bean accessions and a total number of 346 amplicons were
generated. Around 60% of amplicons displayed a polymorphic pattern among different accessions. Cluster analysis on morphological,
technological, chemical and molecular data placed the all five ‘Larga di Leonforte’ accessions into a separated group, and
the Sicilian material shares a fairly large amount of similarity with respect to the cultivar ‘Aguadulce Samba’ selected in
Spain. 相似文献
253.
Marra Elena Laschi Andrea Fabiano Fabio Foderi Cristiano Neri Francesco Mastrolonardo Giovanni Nordfjell Tomas Marchi Enrico 《European Journal of Forest Research》2022,141(1):71-86
European Journal of Forest Research - Intensive forestry operations may cause soil compaction, plastic soil disturbances and rutting, which are responsible for undesirable effects on soils,... 相似文献
254.
May Christine Modenesi-Gauttieri Maria Cristina Motta de Toledo Silvio Takashi Hiruma Fabio Taioli Helio Shimada 《CATENA》2011,85(3):221-230
The thick weathering profiles of humid tropical areas are an important, yet generally neglected, source of information on landscape evolution. Six complete profiles of the weathering mantle were sampled by drilling on the three stepped levels of the Campos do Jordão Plateau, on the NW flank of the Continental Rift of Southeastern Brazil. Mineralogical and micromorphological analyses of drill core samples, complemented by geochemical interpretations and by previous data on the upper saprolite, indicate continuity of a general lateritic trend during the entire process of mantle formation. Lateritization phases of different intensity were defined and considered to reflect adjustment to changes in environmental conditions created by the gradual uplift of the plateau to its present position. Older and more superficial materials related to intense lateritic weathering are characterized by allitization with direct formation of gibbsite from silicates, probably related to tropical climates existing immediately before the formation of the continental rift, during the Paleogene, and also before any significant increase in altitude. Monosialitization phase with general kaolinitization and restricted indirect formation of gibbsite from silicates could be associated to less aggressive climates that followed the Neogene (Miocene?) accentuation of uplift rates along the continental rift. The changes produced by uplift in the tropical climate eventually favored the development of a podzolization trend in soils above 1800 m. 相似文献
255.
256.
Reale F Parenti S Reeves KK Weber M Bobra MG Barbera M Kano R Narukage N Shimojo M Sakao T Peres G Golub L 《Science (New York, N.Y.)》2007,318(5856):1582-1585
The determination of the fine thermal structure of the solar corona is fundamental to constraining the coronal heating mechanisms. The Hinode X-ray Telescope collected images of the solar corona in different passbands, thus providing temperature diagnostics through energy ratios. By combining different filters to optimize the signal-to-noise ratio, we observed a coronal active region in five filters, revealing a highly thermally structured corona: very fine structures in the core of the region and on a larger scale further away. We observed continuous thermal distribution along the coronal loops, as well as entangled structures, and variations of thermal structuring along the line of sight. 相似文献
257.
He Y Tang RH Hao Y Stevens RD Cook CW Ahn SM Jing L Yang Z Chen L Guo F Fiorani F Jackson RB Crawford NM Pei ZM 《Science (New York, N.Y.)》2004,305(5692):1968-1971
The correct timing of flowering is essential for plants to maximize reproductive success and is controlled by environmental and endogenous signals. We report that nitric oxide (NO) repressed the floral transition in Arabidopsis thaliana. Plants treated with NO, as well as a mutant overproducing NO (nox1), flowered late, whereas a mutant producing less NO (nos1) flowered early. NO suppressed CONSTANS and GIGANTEA gene expression and enhanced FLOWERING LOCUS C expression, which indicated that NO regulates the photoperiod and autonomous pathways. Because NO is induced by environmental stimuli and constitutively produced, it may integrate both external and internal cues into the floral decision. 相似文献
258.
259.
Chiara Bernardini Ester Grilli Johanna Catharina Duvigneau Augusta Zannoni Benedetta Tugnoli Fabio Gentilini Terenzio Bertuzzi Silvia Spinozzi Cecilia Camborata Maria Laura Bacci Andrea Piva Monica Forni 《Research in veterinary science》2014
Aim of this study was to characterize the effects of an ochratoxin A (181 ± 34 ng/g) contaminated diet on growth performances, blood parameters, systemic cytokine levels, cell stress markers and reactivity of immune system of weaned pigs. 相似文献
260.
Fermentation by selected sourdough lactic acid bacteria to decrease coeliac intolerance to rye flour 总被引:2,自引:0,他引:2
Maria De Angelis Rossana Coda Marco Silano Fabio Minervini Carlo G. Rizzello Raffaella Di Cagno Olimpia Vicentini Massimo De Vincenzi Marco Gobbetti 《Journal of Cereal Science》2006,43(3):301-314
A pool of selected lactic acid bacteria was used to ferment suspensions of rye flour. Two-dimensional electrophoresis showed that 109 of the 129 ethanol-soluble rye polypeptides were hydrolysed almost totally by lactic acid bacteria. Matrix-assisted laser desorption ionization—time of flight mass spectrometry and reversed-phase high performance liquid chromatography analysis confirmed the hydrolysis of prolamins. After 48 h fermentation, no prolamin polypeptides were recognized by R5-Western analysis. HPLC analysis of glutelin polymers showed a very low bacterial proteolysis but a pH dependent hydrolysis probably due to activation of rye enzymes. Prolamins were extracted from rye flour and used to produce a peptic–tryptic (PT)-digest for in vitro tests with K 562 (S) sub-clone and Caco-2/TC7 cells of human origin. The PT-digest was also treated with lactic acid bacteria before assay. The Minimal Agglutinating Capacity increased ca. 8-times when K 562 (S) sub-clone cells were exposed to rye PT-digest treated with lactic acid bacteria. Hydrolysis of rye PT-digest by lactic acid bacteria decreased the toxicity of PT-digest itself towards Caco-2/TC7 cells as estimated by cell viability, caspase-3 activity and release of nitric oxide. Rye prolamins and glutelins were extracted from doughs and subjected to PT digestion. Compared to PT-digests from chemically acidified dough, coeliac jejunal biopsies exposed to the PT-digest from the dough fermented by lactic acid bacteria did not show an increase of the infiltration of CD3+ intraepithelial lymphocytes. The same was found for epithelial cell Fas expression. Long-time fermentation of dough by selected lactic acid bacteria could be considered as a potential tool to decrease the risk of rye contamination of gluten-free products for coeliac patients. 相似文献