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41.
Maria Sofia Vieira-Rocha Pilar Rodriguez-Rodriguez Mariana Ferreira-Duarte Miguel Faria Joana Beatriz Sousa Manuela Morato Silvia Magdalena Arribas Carmen Diniz 《International journal of molecular sciences》2022,23(3)
Fetal stress is known to increase susceptibility to cardiometabolic diseases and hypertension in adult age in a process known as fetal programming. This study investigated the relationship between vascular RAS, oxidative damage and remodeling in fetal programming. Six-month old Sprague-Dawley offspring from mothers that were fed ad libitum (CONTROL) or with 50% intake during the second half of gestation (maternal undernutrition, MUN) were used. qPCR or immunohistochemistry were used to obtain the expression of receptors and enzymes. Plasma levels of carbonyls were measured by spectrophotometry. In mesenteric arteries from MUN rats we detected an upregulation of ACE, ACE2, AT1 receptors and NADPH oxidase, and lower expression of AT2, Mas and MrgD receptors compared to CONTROL. Systolic and diastolic blood pressure and plasma levels of carbonyls were higher in MUN than in CONTROL. Vascular morphology evidenced an increased media/lumen ratio and adventitia/lumen ratio, and more connective tissue in MUN compared to CONTROL. In conclusion, fetal undernutrition indices RAS alterations and oxidative damage which may contribute to the remodeling of mesenteric arteries, and increase the risk of adverse cardiovascular events and hypertension. 相似文献
42.
43.
A study was carried out to increase the CLA contents in ewes’ milk fat under field conditions by dietary means and to investigate
the extent of the changes and consequences for milk processing and cheese quality. During a 3-mon period, ewes’ bulk milk
samples were collected every week from two different herds. For the first 4 wk the ewes were fed a conventional diet. Then
the following 6 wk a supplement enriched in α-linolenate (whole linseed) was incorporated into the ovine diet. Finally, in
the last 3 wk the feeding was the same as in the first 4 wk. The FA profile in milk fat was monitored by GC, and the distribution
of CLA isomers was thoroughly tested by combining GC-MS of 4,4-dimethyloxazoline derivatives (DMOX) with silver ion-HPLC (Ag+-HPLC) of FAME. Reconstructed mass spectral profiles of CLA characteristic ions from DMOX were used to identify positional
isomers, and Ag+-HPLC was used to quantify them. An increase in total CLA in milk fat was observed, and total CLA remained elevated during
the weeks of enriched α-linolenate feeding. In our experimental conditions there was a linear relationship between trans-vaccenic acid (trans-11-octadecenoic acid; trans-11 18∶1) and 9-cis, 11-trans CLA in ewes’ milk fat. Concerning the CLA isomer profile, increases in the 11,13- and 12,14–18∶2 positional isomers were
considerable when linseed was included in the diet. Organoleptic characteristics of cheeses made with CLA-enriched milk did
not substantially differ from those made with nonsupplemented ewes’ milk. CLA total content and isomer profile did not change
during ripening. 相似文献
44.
Sarah Laraichi Pilar Parra Rocío Zamanillo Ahmed El Amarti Andreu Palou Francisca Serra 《Lipids》2013,48(8):817-826
The scope of this study was to assess the impact of calcium and conjugated linoleic acid (CLA) supplementation on plasma fatty acid profiles and to evaluate potential synergistic effects of both compounds against dietary obesity. Mice separated into five experimental groups were followed: control (C), high-fat diet (HF), HF with calcium (Ca), HF plus CLA and HF with both Ca and CLA. Plasma metabolites and fatty acids were determined by commercial kits and gas chromatography, respectively. Both dietary calcium and CLA supplementation contributed to lower body fat gain under a HF diet. Maximum efficacy was seen with calcium; no additional effect was associated with the combined treatment with CLA. Plasma leptin, adiponectin and HOMA index were in accordance with an altered glucose/insulin homeostasis in the HF and HF + CLA groups, whereas control levels were attained under Ca-enriched diets. Plasma fatty acids showed minor changes associated to CLA treatment, but a high impact on PUFA was observed under Ca-enriched diets. Our results show that the mechanism underlying the anti-obesity effects of calcium supplementation is mediated mainly by changes in PUFA plasma profile. In addition, the lack of synergy on body weight reduction in combination with associated lipid profiles of calcium and CLA suggests that calcium may interfere with absorption and/or bioactivity of CLA, which can be of relevance when using CLA-fortified dairy products against human obesity. 相似文献
45.
Karola B?hme Inmaculada C. Fern��ndez-No Jose M. Gallardo Benito Ca?as Pilar Calo-Mata 《Food and Bioprocess Technology》2011,4(6):907-918
Foodborne intoxications caused by the consumption of fish and other products of marine origin contaminated with bacterial
pathogens are an ever-present threat, either due to bacteria and/or its metabolites. In addition, the rapid spoilage of seafood
due to microbial activity, results in high economic losses. The development of the microbiota in seafood products depends
on the microbiological ambience of capture, processing and storage, and the applied preservation method. Thus, pathogenic
and spoilage bacterial species in seafood may come from the indigenous microbiota of the aquatic ambience or are introduced
by contamination during processing. Rapid and accurate bacterial species identification is essential for an effective control
program to ensure safety and quality of either processed or minimally processed seafood. In the present work, matrix-assisted
laser desorption ionization-time of flight mass spectrometry was successfully applied to identify 26 bacterial strains isolated
from fresh fish and processed seafood samples. The approach was based on the comparison of unknown spectra to a reference
spectral library and demonstrated to be a fast and accurate technique for bacterial species differentiation, which can be
used for the rapid identification of foodborne pathogens and spoilage bacteria potentially present in products of marine origin. 相似文献
46.
Antonia Picon Rocío Alonso Pilar Gaya Manuel Nuñez 《Food and Bioprocess Technology》2013,6(10):2820-2830
High-pressure treatment of raw goat milk curd was investigated as an alternative to thermal treatment of milk in cheese manufacture, and curd freezing as a procedure to surmount the seasonality of goat milk production. Experimental cheeses were made by mixing (70:30) fresh cow milk curd with frozen curd from pasteurized goat milk (PGC), frozen curd from raw goat milk (RGC), or frozen pressurized curd from raw goat milk (PRGC). Control cheese was made from a mixture (70:30) of pasteurized cow and goat milk. RGC cheese showed the highest counts of staphylococci, Gram-negative bacteria and coliforms, whereas PRGC cheese had maximum aminopeptidase activity, esterase activity, and overall proteolysis. Control cheese exhibited the highest dry matter content and peptide levels, the lowest concentration of free amino acids, the highest concentration of volatile compounds such as free fatty acids, alcohols and esters, and the firmest texture. Differences in sensory characteristics between experimental and control cheeses were of minor importance. High-pressure treatment of curd allowed the production of cheese of bacteriological quality similar to that of control cheese made using pasteurized milk, while curd freezing did not alter the sensory characteristics of experimental cheeses with respect to control cheese. 相似文献
47.
Monica Cavia‐Saiz Maria D Busto Maria Concepción Pilar‐Izquierdo Natividad Ortega Manuel Perez‐Mateos Pilar Muñiz 《Journal of the science of food and agriculture》2010,90(7):1238-1244
BACKGROUND: This study was designed to evaluate and compare antioxidant capacity and radical scavenging activity of naringin and its aglycone by different in vitro assays. The effects of flavanones on lipid peroxidation, glutathione (GSH) oxidation and DNA cleavage were also assessed. RESULTS: The results showed that naringenin exhibited higher antioxidant capacity and hydroxyl and superoxide radical scavenger efficiency than naringin. Our results evidenced that glycosylation attenuated the efficiency in inhibiting the enzyme xanthine oxidase and the aglycone could act like a more active chelator of metallic ions than the glycoside. Additionally, naringenin showed a greater effectiveness in the protection against oxidative damage to lipids in a dose‐dependent manner. Both flavanones were equally effective in reducing DNA damage. However, they show no protective effect on oxidation of GSH. CONCLUSION: The data obtained support the importance of characterizing the ratio naringin/naringenin in foods when they are evaluated for their health benefits. Copyright © 2010 Society of Chemical Industry 相似文献
48.
Arnaud Barbier Guy-Antonin Martin Pilar Ramirez de la Piscina Narcis Homs 《Applied Catalysis A: General》2001,210(1-2):75-81
The hydrogenation of carbon monoxide over Co/SiO2 catalysts obtained by reduction of precursors prepared by the reaction of dicobaltoctacarbonyl with silica gives rise to a mixture of alcohols and hydrocarbons. The chain growth probability for hydrocarbon synthesis is similar to that observed over conventional catalysts prepared by the ammonia method (=0.74) with a comparable metal dispersion (metal particle size 4 nm). Alcohol formation yields a smaller chain growth probability (=0.42). Magnetic measurements have shown that in the latter catalyst, small cobalt clusters (1 nm) are likely to be present together with the cobalt particles (4 nm), this observation reconciles apparently conflicting results from the literature. It has been speculated that alcohol formation might be related to the presence of these clusters according to a concerted mechanism. Furthermore, the observation of large amounts of acetates by temperature-programmed hydrogenation, not detected in hydrocarbon selective catalysts, suggests that they may play a role in ethanol synthesis. 相似文献
49.
Polythene films coated with the enterococcal bacteriocin enterocin EJ97 alone or in combination with EDTA were tested against Bacillus coagulans CECT 12. Bacteriocin activity was clearly enhanced by EDTA, as shown by viable staining and epifluorescence microscopy observation of treated cells. Activated films were tested in liquids from canned corn and canned peas inoculated with B. coagulans cell suspensions and stored at 4 °C and 20 °C for 24 h. The bacteriocin alone showed highest activity in samples stored at 4 °C, while the maximum performance of EDTA was observed at 20 °C. Films activated with a combination of both antimicrobials showed highest bactericidal activity at 4 °C. In liquid from canned corn and peas stored at 4 °C, the combined treatment reduced the concentrations of viable cells progressively over incubation time. Viable staining revealed an increase in the percentage of dead cells at 20 °C, avoiding proliferation of the bacilli. The bactericidal effect of the combined antimicrobial agents was higher in the liquid of canned peas than that of canned corn. The combined use of viable staining and classical viable cell counts allowed a better estimation of cell damage caused by the antimicrobial treatments. 相似文献
50.
Juan R. Gonzlez-Velasco Miguel A. Gutirrez-Ortiz Jean-Louis Marc M. Pilar Gonzlez-Marcos Gilbert Blanchard 《Applied catalysis. B, Environmental》2001,33(4):452-314
A number of experiments were carried out with fresh and aged high surface area Ce0.68Zr0.32O2 mixed oxide samples with complex feed-streams in order to determine their performance as three way catalyst (TWC). The results confirmed the oxygen storage capacity (OSC) of these samples, which favour NO conversion in cycled versus stationary stoichiometric operation. Several experiments carried out with different feed-streams have shown that a pre-reducing treatment can significantly improve both NO reduction at low-temperature and selectivity to N2, which can be very useful to reduce the emission of nitrogen oxides immediately after starting the automobile. Although a significant reduction of the specific surface area of the mixed oxide takes place during ageing at 1173 K, it has been shown that the performance of the sample remains similar or even better than when fresh, due to an increased OSC. Thus, the reduction of CO and hydrocarbon emissions during start could be achieved by situating the catalytic converter nearer the exhaust to the engine, where the catalyst will be heated faster. 相似文献