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81.
The steryl ester and phospholipid fractions of the marine spongeAgelas conifera were isolated and analyzed. The fatty acyl components of the steryl ester and phospholipid fractions as determined by gas
chromatography and gas chromatography/mass spectrometry were very similar and consisted of 56.8 and 62.7% of C14−C20 acids (normal; branched, especiallyiso andanteiso; and monounsaturated, particularly Δ9 and Δ11 acids) and of 43.1 and 35.5% of C24−C26 acids (Δ5,9 diunsaturated acids), respectively. The major constituent fatty acids detected were 13-methyltetradecanoic,n-hexadecanoic, 10-methylhexadecanoic, 11-octadecenoic, 12-methyloctadecanoic, 5,9-pentacosadienoic and 5,9-hexacosadienoic
acids. The phospholipids isolated were identified as phosphatidylcholine (37%), phosphatidylserine (34%), phosphatidylethanolamine
(16%) and phosphatidylinositol (11%). The distribution of fatty acids within the phospholipid classes was also determined. 相似文献
82.
Ruben Ramírez‐Gómez Daniel García‐Cortés Gaston Martínez‐de Jesús Margarita M. González‐Brambila Alejandro Alonso Sergio A. Martínez‐Delgadillo Jorge Ramírez‐Muñoz 《化学工程与技术》2015,38(9):1519-1529
High‐shear impellers (HSIs) are mixers used in industrial stirred tanks to incorporate powders into liquids and break down particle agglomerates. A detailed numerical study of two commercial ring‐style HSIs of laboratory scale was carried out and their performance was compared with the Rushton turbine (RT). It was found that power and pumping numbers or their ratio cannot be simply connected for properly selecting an impeller in applications where highly localized viscous dissipation is desirable. The ratio of the average viscous dissipation in the impeller swept volume to the mean in the entire volume at two constant values of power input turned out to be lower for HSIs compared to that evaluated for RT. However, at higher power input, the dimensionless average viscous dissipation in the blade swept volume was found to be similar for the HSI of two rings and the RT, corroborating the high local viscous dissipation of this HSI when operated at higher speeds. 相似文献
83.
Novel Tacrine‐Grafted Ugi Adducts as Multipotent Anti‐Alzheimer Drugs: A Synthetic Renewal in Tacrine–Ferulic Acid Hybrids 下载免费PDF全文
Mohamed Benchekroun Dr. Manuela Bartolini Dr. Javier Egea Dr. Alejandro Romero Dr. Elena Soriano Dr. Marc Pudlo Vincent Luzet Prof. Vincenza Andrisano Dr. María‐Luisa Jimeno Dr. Manuela G. López Sarah Wehle Prof. Tijani Gharbi Prof. Bernard Refouvelet Lucía de Andrés Clara Herrera‐Arozamena Prof. Barbara Monti Prof. Maria Laura Bolognesi Prof. María Isabel Rodríguez‐Franco Prof. Dr. Michael Decker Prof. José Marco‐Contelles Dr. Lhassane Ismaili 《ChemMedChem》2015,10(3):523-539
Herein we describe the design, multicomponent synthesis, and biological, molecular modeling and ADMET studies, as well as in vitro PAMPA‐blood–brain barrier (BBB) analysis of new tacrine–ferulic acid hybrids (TFAHs). We identified (E)‐3‐(hydroxy‐3‐methoxyphenyl)‐N‐{8[(7‐methoxy‐1,2,3,4‐tetrahydroacridin‐9‐yl)amino]octyl}‐N‐[2‐(naphthalen‐2‐ylamino)2‐oxoethyl]acrylamide (TFAH 10 n ) as a particularly interesting multipotent compound that shows moderate and completely selective inhibition of human butyrylcholinesterase (IC50=68.2 nM ), strong antioxidant activity (4.29 equiv trolox in an oxygen radical absorbance capacity (ORAC) assay), and good β‐amyloid (Aβ) anti‐aggregation properties (65.6 % at 1:1 ratio); moreover, it is able to permeate central nervous system (CNS) tissues, as determined by PAMPA‐BBB assay. Notably, even when tested at very high concentrations, TFAH 10 n easily surpasses the other TFAHs in hepatotoxicity profiling (59.4 % cell viability at 1000 μM ), affording good neuroprotection against toxic insults such as Aβ1–40, Aβ1–42, H2O2, and oligomycin A/rotenone on SH‐SY5Y cells, at 1 μM . The results reported herein support the development of new multipotent TFAH derivatives as potential drugs for the treatment of Alzheimer′s disease. 相似文献
84.
Karen Valencia G. Alejandro López Agileo Hernández-Gordillo Rodolfo Zanella Sandra E. Rodil 《Ceramics International》2018,44(18):22329-22338
Stabilized tetragonal Bi2O3 nanoparticles (β-Bi2O3) were obtained by annealing treatments of amorphous Bi-based precursors, obtained by chemical precipitations, at temperatures between 350 and 450?°C. The formation of the stabilized β-Bi2O3 phase was possible by using (BiO)4CO3(OH)2 while other precursors such as amorphous bismuth carbonate ((BiO)2CO3) and amorphous basic bismuth nitrate (Bi6O6(OH)2(NO3)4·2H2O) led to the formation of the thermodynamically stable monoclinic α-Bi2O3 and Bi5O7NO3 phases. The Bi-based precursors were prepared by the chemical precipitation method at room temperature in ethylenediamine-solvent varying the HNO3/Bi3+ molar ratio (10, 26 and 56). The physicochemical properties of the three as-prepared amorphous precursors and the formed-after-calcination β-Bi2O3, α-Bi2O3 and Bi5O7NO3 phases were analyzed by X-ray diffraction, scanning electron microscopy, thermogravimetry, X-ray photoelectron spectroscopy (XPS), FTIR analysis, diffuse reflectance spectroscopy and surface area by BET method. The photocatalytic activity of all annealed solids containing the β-Bi2O3 phase was tested in the photodegradation of the indigo carmine (IC) dye under specific blue light. A schematic diagram of the Bi2O3 phases obtained as a function of the annealing conditions and initial amorphous precursor is proposed and explained in terms of the amount of CO32-, NO3- and amine (ENH22+ ? ENH+) ions present in each bismuth precursor. 相似文献
85.
Chemical and enzymatic interesterification are used to create spreadable fats. However, a comparison between the two processes
in terms of their acute metabolic effects has not yet been investigated. A randomised crossover study in obese (plasma TAG > 1.69 mmol/L,
and BMI > 30 (BMI = kg/m2) or waist circumference > 102 cm, n = 11, age = 59.3 ± 1.8 years) and non-obese (plasma triacylglycerol (TAG) < 1.69 mmol/L, and BMI < 30 or waist circumference < 102 cm,
n = 10, age = 55.8 ± 2.2 years) men was undertaken to compare the effects of chemical versus enzymatic interesterification
on postprandial risk factors for type 2 diabetes (T2D) and cardiovascular disease (CVD). TAG, cholesterol, glucose, insulin
and free fatty acid concentrations were measured for 6 h following consumption of 1 g fat/kg body mass of non-interesterified
(NIE), chemically interesterified (CIE), enzymatically interesterified (EIE) stearic acid-rich fat spread or no fat, each
with 50 g available carbohydrate from white bread. Interesterification did not affect postprandial glucose, insulin, free
fatty acids or cholesterol (P > 0.05). Following ingestion of NIE, increases in serum oleic acid were observed, whereas both oleic and stearic acids were
increased with CIE and EIE (P < 0.05). While postprandial TAG concentrations in non-obese subjects were not affected by fat treatment (P > 0.05), obese subjects had an 85% increase in TAGs with CIE versus NIE (P < 0.05). The differences in TAG response between non-obese and obese subjects suggest that interesterification may affect
healthy individuals differently compared to those already at risk for T2D and/or CVD. 相似文献
86.
87.
Jack A. Neal Betsy Booren Luis Cisneros-Zevallos Rhonda K. Miller Lisa M. Lucia Joseph E. Maxim Alejandro Castillo 《Journal of food science》2010,75(6):S319-S326
Abstract: The use of ionizing radiation for the control of foodborne pathogens and extending the shelf life of fresh iceberg lettuce and fresh spinach has recently been approved by the U.S. Food and Drug Administration. The efficacy of electron beam irradiation for controlling foodborne pathogens has been reported. For this experiment, the effectiveness of electron beam irradiation on the microbiological and sensory characteristics of fresh spinach was studied. Total aerobic plate counts were reduced by 2.6 and 3.2 log CFU/g at 0.7 and 1.4 kGy, respectively. Lactic acid bacteria were reduced at both doses of e-beam but grew slowly over the 35 d of the experiment. Yeasts and molds were not reduced in samples exposed to 0.7 kGy whereas 1.4 kGy significantly reduced microbial counts. Gas compositions (O2 and CO2) were significantly different than controls. Oxygen levels inside the spinach sample bags decreased over time; however, O2 levels did not drop below 1% that can induce anaerobic fermentation. CO2 levels for all treatments increased through day 4; yet 7 d after irradiation, CO2 level differences were not significant in both control and irradiated samples. Irradiation dose did not affect the basic tastes, aromatics, or mouth feels of fresh spinach, however; hardness attributes decreased as irradiated dose increased and slimy attributes of fresh spinach were higher in control samples compared to irradiated samples. 相似文献
88.
Trewartha Kevin M.; Endo Alejandro; Li Karen Z. H.; Penhune Virginia B. 《Canadian Metallurgical Quarterly》2009,24(2):450
Two experiments were designed to explore how age differences in conflict detection may contribute to poorer motor performance. In each experiment, 12 young adults (YAs) and 12 older adults (OAs) performed a finger sequencing task in which the frequency of specific critical transitions was varied. These critical transitions were contrasted with violation transitions to assess the ability to detect a conflict in response requirements. In addition to accuracy and reaction time, the authors used kinematic data to parse movements into planning and motor execution phases. OAs were differentially slower to respond to violations than YAs, in line with other research on executive control, prepotent response suppression, and aging. Kinematic analyses revealed that YAs executed movements more rapidly on violation than critical transitions, whereas OAs executed movements at the same speed regardless of response predictability and increased planning time. The authors argue that OAs are unable to reprogram prepotent movement plans to overcome slowed movement planning in cognitively challenging situations. The results are discussed in terms of the influence of age-related cognitive inefficiency on motor control. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Alejandro Peña P Jesús A. Hernández Victoria M. Toro 《Environmental Modelling & Software》2010,25(12):1890-1893
This article presents a model based on the principles of evolutionary computation and on the principles of dispersion of an Inverse lagrangian puff model of the type Backward gaussian puff tracking in order to determine the spatial behavior over time of the concentration for PM2.5 and PM10 in a study area. 相似文献
90.
Alejandro Rodríguez-Castellanos José E. Rodríguez-Sánchez Manuel Carbajal-Romero 《Canadian Metallurgical Quarterly》2009,135(12):1971-1975
A matrix formulation to determine the coupled response of rigid foundations where soil properties are modeled by springs and dashpots is presented. Location and orientation of springs and dashpots can be arbitrary, thus a general solution is determined. The response is given in terms of translational and rotational displacements considering coupled effects. Physics of the problem presented here has been extensively studied and a broad range of useful formulae to determine springs and dashpots properties for soil-structure interaction is available. These published formulae for springs and dashpots properties are an input to the approach presented. Thus, the novelty of this approach is a matrix manipulation that leads to a simple expression allowing coupling all degrees of freedom even when springs and dashpots are not orthogonally oriented. For validation purposes, finite element solutions are compared with the approach presented. 相似文献