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81.
P Ferroni L Lenti F Martini F Ciatti GM Pontieri PP Gazzaniga 《Canadian Metallurgical Quarterly》1997,77(3):548-554
Gangliosides may play functional roles in platelet physiology, therefore this study has been designed to evaluate whether changes in ganglioside composition may occur as a consequence of platelet activation. The results obtained indicate that lactosylceramide and GM3 are the major glycosphingolipids of human platelets. The lipid-bound sialic acid (LBSA) content was 1.27 +/- 0.04 micrograms/mg of protein. Resting platelets did not express GD3; GD3 was synthesized upon platelet activation (24 +/- 8 ng/mg of protein). The stimulation of platelets with adenosine diphosphate showed the appearance of GD3 even in the absence of degranulation. Finally, incorporation of pyrene-labeled GM3 into platelet membranes, followed by stimulation with adenosine diphosphate, resulted in the appearance of a fluorescent band comigrating with GD3. The present studies indicate that sialytransferase activation may occur as an early event following platelet stimulation, leading to GD3 synthesis mainly from the GM3 pool. 相似文献
82.
Jorge Regueiro Olalla López-Fernández Raquel Rial-Otero Beatriz Cancho-Grande 《Critical reviews in food science and nutrition》2015,55(6):839-863
Residues of pesticides in food are influenced by processing such as fermentation. Reviewing the extensive literature showed that in most cases, this step leads to large reductions in original residue levels in the fermented food, with the formation of new pesticide by-products. The behavior of residues in fermentation can be rationalized in terms of the physical-chemical properties of the pesticide and the nature of the process. In addition, the presence of pesticides decrease the growth rate of fermentative microbiota (yeasts and bacterias), which provokes stuck and sluggish fermentations. These changes have in consequence repercussions on several aspects of food sensory quality (physical-chemical properties, polyphenolic content, and aromatic profile) of fermented food. The main aim of this review is to deal with all these topics to propose challenging needs in science-based quality management of pesticides residues in food. 相似文献
83.
84.
Whey cheeses have been manufactured with probiotic bacteria - viz. Bifidobacterium animalis Bo and Lactobacillus casei LAFTI®L26, from combinations of bovine whey and milk, following protein denaturation at 90 °C; they were subsequently inoculated (at 10%) with those strains, and homogenized afterwards; additives such as salt and sugar were then incorporated; and the resulting solid matrices were stored at 7° C for up to 21 d. Oscillatory measurements and instrumental texture profile analyses were performed, and sensory analyses were carried out by a trained panel. Microstructural features were in addition ascertained by scanning electron microscopy.L. casei exhibited a higher acidifying activity than B. animalis, which produced distinct textures; higher firmness and viscoelasticity were indeed found in matrices inoculated with the former. Incorporation of sugar and L. casei favoured consumer acceptability, relative to plain matrices. Microstructural differences were detected between matrices at different times of storage and formulated with distinct additives. 相似文献
85.
Jiraporn Ousingsawat Raquel Centeio Inês Cabrita Khaoula Talbi Oliver Zimmer Moritz Graf Achim Gpferich Rainer Schreiber Karl Kunzelmann 《International journal of molecular sciences》2022,23(3)
Repurposing of the anthelminthic drug niclosamide was proposed as an effective treatment for inflammatory airway diseases such as asthma, cystic fibrosis, and chronic obstructive pulmonary disease. Niclosamide may also be effective for the treatment of viral respiratory infections, such as SARS-CoV-2, respiratory syncytial virus, and influenza. While systemic application of niclosamide may lead to unwanted side effects, local administration via aerosol may circumvent these problems, particularly when the drug is encapsulated into small polyethylene glycol (PEG) hydrospheres. In the present study, we examined whether PEG-encapsulated niclosamide inhibits the production of mucus and affects the pro-inflammatory mediator CLCA1 in mouse airways in vivo, while effects on mucociliary clearance were assessed in excised mouse tracheas. The potential of encapsulated niclosamide to inhibit TMEM16A whole-cell Cl− currents and intracellular Ca2+ signalling was assessed in airway epithelial cells in vitro. We achieved encapsulation of niclosamide in PEG-microspheres and PEG-nanospheres (Niclo-spheres). When applied to asthmatic mice via intratracheal instillation, Niclo-spheres strongly attenuated overproduction of mucus, inhibited secretion of the major proinflammatory mediator CLCA1, and improved mucociliary clearance in tracheas ex vivo. These effects were comparable for niclosamide encapsulated in PEG-nanospheres and PEG-microspheres. Niclo-spheres inhibited the Ca2+ activated Cl− channel TMEM16A and attenuated mucus production in CFBE and Calu-3 human airway epithelial cells. Both inhibitory effects were explained by a pronounced inhibition of intracellular Ca2+ signals. The data indicate that poorly dissolvable compounds such as niclosamide can be encapsulated in PEG-microspheres/nanospheres and deposited locally on the airway epithelium as encapsulated drugs, which may be advantageous over systemic application. 相似文献
86.
Irene Peinado Isabel Moya Laura García-Valverde Raquel Francs Rosana Ribes Patrocinio Polo María Jos Gmez-Torres Ana Monz 《International journal of molecular sciences》2023,24(1)
How does the in vitro maturation (IVM) medium and the vitrification procedure affect the survival of germinal vesicle (GV) oocytes obtained from stimulated cycles and their development to the blastocyst stage? In total, 1085 GV human oocytes were obtained after women underwent a cycle of controlled ovarian stimulation, and these oocytes were subjected to IVM before or after their vitrification. IVM was carried out in two commercial culture media not specifically designed for maturation. MII oocytes were then activated and embryo development until day 6 was evaluated. According to the results, a higher percentage of oocytes reach the MII stage if they are vitrified before they undergo IVM. Nevertheless, the medium used and the sample size determine whether these differences become significant or not. Similar survival rates and development to blastocysts were observed in all the conditions studied. 相似文献
87.
Adriana Tedesco Patrícia F Krey Ronilson V Barbosa Raquel S Mauler 《Polymer International》2002,51(2):105-110
Polyamide and polypropylene (PP) are two important classes of commercial polymers; however, their direct mixing leads to incompatible blends with poor properties. Polypropylene functionalized with glycidyl methacrylate (PP‐GMA) was used as a compatibilizer in blends of PP and nylon 6, because of the possible reaction of ? NH2 and ? COOH groups with the epoxide group of GMA. Two types of nylon 6 with different ratios between ? NH2 and ? COOH groups were used. The one with higher concentration of ? COOH groups was less compatible with PP in a binary blend. When PP‐GMA was used as a compatibilizer, a better dispersion of nylon in the PP matrix was obtained together with better mechanical properties for both nylons used in this work. © 2001 Society of Chemical Industry 相似文献
88.
Marina Cerdeira Valentina Pastore Liliana V. Vera Silvana Martini Roberto J. Candal María L. Herrera 《European Journal of Lipid Science and Technology》2005,107(12):877-885
The effect of highly hydrophobic emulsifiers, the palmitic sucrose ester P‐170 (hydrophilic/lipophilic balance (HLB) = 1.0), the stearic sucrose ester S‐170 (HLB = 1.0), the polyglycerol ester decaglycerol decastearate DAS 7S (HLB = 3.7) and the polyglycerol ester decaglycerol dodecabehenate DDB 750 (HLB = 2.6), on the nucleation of a high melting point milk fat fraction (HMF) and its blends with sunflower oil (SFO) was investigated by polarized laser light turbidimetry, X‐ray diffractometry and polarized light microscopy (PLM). Addition of polyglycerol esters accelerated nucleation, giving shorter induction times for the same supercooling. On the contrary, sucrose esters inhibited nucleation since induction times were elongated in all conditions selected. Addition of emulsifiers modified the polymorphic behavior in the blends with SFO. The β' form was promoted especially with the addition of S‐170. DAS 7S and DDB 750 promoted crystallization. PLM images showed many small crystals that did not appear in HMF images. Addition of P‐170 and S‐170 delayed nucleation and inhibited crystal growth. Crystals were notoriously smaller than the ones that appeared in HMF images. The Fisher–Turnbull model was used to calculate activation free energies of nucleation. In all cases, sucrose esters elevated the energy barrier for nucleation. Polyglycerol esters, however, if they had an effect on the energy barrier, lowered the values. 相似文献
89.
This study examined the relationship between functional brain asymmetry, as measured by the characteristic direction of eye movements in response to face-to-face questioning, and sitting on the left or the right side of a classroom: 74 undergraduate students, whose laterality had previously been ascertained, participated. As predicted, left movers preferred to sit on the right side, and right movers on the left. A significant proportion of the subjects who indicated a differential seating preference for hard compared to soft topics, placed themselves more to the left for the former. The results are congruent with other findings comparing right movers and left movers on a variety of personality measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Farfaletti A Astorga C Martini G Manfredi U Mueller A Rey M De Santi G Krasenbrink A Larsen BR 《Environmental science & technology》2005,39(17):6792-6799
One of the major technological challenges for the transport sector is to cut emissions of particulate matter (PM) and nitrogen oxides (NOx) simultaneously from diesel vehicles to meet future emission standards and to reduce their contribution to the pollution of ambient air. Installation of particle filters in all existing diesel vehicles (for new vehicles, the feasibility is proven) is an efficient but expensive and complicated solution; thus other short-term alternatives have been proposed. It is well known that water/diesel (W/ D) emulsions with up to 20% water can reduce PM and NOx emissions in heavy-duty (HD) engines. The amount of water that can be used in emulsions for the technically more susceptible light-duty (LD) vehicles is much lower, due to risks of impairing engine performance and durability. The present study investigates the potential emission reductions of an experimental 6% W/D emulsion with EURO-3 LD diesel vehicles in comparison to a commercial 12% W/D emulsion with a EURO-3 HD engine and to a Cerium-based combustion improver additive. For PM, the emulsions reduced the emissions with -32% for LD vehicles (mass/km) and -59% for the HD engine (mass/ kWh). However, NOx emissions remained unchanged, and emissions of other pollutants were actually increased forthe LD vehicles with +26% for hydrocarbons (HC), +18% for CO, and +25% for PM-associated benzo[a]pyrene toxicity equivalents (TEQ). In contrast, CO (-32%), TEQ (-14%), and NOx (-6%) were reduced by the emulsion for the HD engine, and only hydrocarbons were slightly increased (+16%). Whereas the Cerium-based additive was inefficient in the HD engine for all emissions except for TEQ (-39%), it markedly reduced all emissions for the LD vehicles (PM -13%, CO -18%, HC -26%, TEQ -25%) except for NOx, which remained unchanged. The presented data indicate a strong potential for reductions in PM emissions from current diesel engines by optimizing the fuel composition. 相似文献