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51.
Beltran E  Pla R  Yuste J  Mor-Mur M 《Meat science》2004,66(3):719-725
Sodium chloride (5%) and some antioxidants (400 ppm rosemary extract; 2000 ppm acerola extract; 50 ppm ethylenediamine tetraacetic acid (EDTA); 1,000, 2,000, and 5,000 pm of sodium hexametaphosphate or 5 and 10% egg white powder) were added to minced chicken. From these mixtures, slurries were made by mixing with water (1:3) at 15,000 rpm for 30 s at 20?°C. Samples were pressurized (300, 500 and 900 MPa for 30 min at 20?°C) or cooked (90?°C for 15 min). Hexanal was quantified by solid phase microextraction at 1, 3, 6 and 9 days of 4?°C storage in contact with air. Hexanal values increased with pressure and storage time. Cooked slurries had higher hexanal contents than samples pressurized at 300 MPa, but lower than those treated at 500 and 900 MPa. Rosemary extract was an antioxidant for pressure-treated samples, but had little effect on cooked ones. Acerola extract was not an effective antioxidant, but EDTA strongly inhibited oxidation. Hexamethaphosphate also showed antioxidant ability. Egg white powder inhibited hexanal generation, which can be a new way for revalorizing egg constituents.  相似文献   
52.
Alcohol use may be viewed as an attempt (albeit maladaptive) to regulate negative emotional states. We examined associations between both negative and positive affects and alcohol use in outpatient women diagnosed with borderline personality disorder (BPD; n = 74), a prototype of emotional dysregulation, as well as a psychiatric control group of women with current depressive disorder (major depressive disorder/dysthymic disorder [MDD\DYS]; n = 50). Participants completed randomly prompted reports of mood and alcohol use up to six times a day over a 28-day period using electronic diaries. Mean levels of either positive or negative affects did not distinguish between drinkers and nondrinkers in either diagnostic group. However, levels of both negative and positive affects were positively associated with alcohol use at the momentary level in BPD drinkers. More robust findings were obtained with respect to within-person affective variability, which was related to alcohol use in multiple ways. BPD drinkers showed higher within-person variability for most negative affects than BPD nondrinkers; MDD\DYS drinkers in general showed less within-person variability than MDD\DYS nondrinkers for negative affects. Multilevel lagged analyses for BPD drinkers indicated that alcohol use was positively related to variability in all affects, concurrently, but fewer significant effects of affect variability on the next day's drinking or significant effects of alcohol use on the next day's affect variability were observed. Among MDD\DYS drinkers, we observed more significant associations between affect variability on next day's alcohol use and of alcohol use on next day's affect variability. We discuss theoretical and methodological issues relevant to these findings as well as implications for future research. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
53.
Biochemical characteristics, including myosin heavy chain I (MHC-I) percentage, isocitrate dehydrogenase and aldolase activities, meat quality traits and instrumental texture properties of rabbits selected for different growth rates were studied. The animals of the control (C) group (7th generation; n=60) were raised in parallel with those of selection (S) group (21st generation; n=60). Carcass weights (1230.1 ± 19.8 and 1348.3 ± 20.1 g, for C and S, respectively) and perirenal and scapular fat content differed significantly (P<0.01) between the two groups. Water holding capacity was expressed as the percentage of pressure released water and was significantly different (P<0.05) between groups C and S (33.29% and 35.57%). MHC-I percentage and aldolase activity also differed significantly (P<0.05) between groups, group C showing higher oxidative traits than group S (MHC-I: 12.5% and 9.8%; aldolase: 597.11 and 636.83 UI/g muscle). Texture properties from the Warner-Bratzler test showed higher (P<0.001) shear firmness for loin in the S group (1.69 kg/s cm2) than in the C group (1.34 kg/s cm2). In addition, the texture profile analysis indicated that chewiness, gumminess and hardness were also higher in the S group (P<0.01). In conclusion, the results confirmed a positive effect of the selection on productive traits and a negative effect on instrumental texture properties and on the water holding capacity of the meat.  相似文献   
54.
Two hundred and eighty-four, genetically similar (a three-way cross), young rabbits were fed ad libitum, from weaning, either a commercial diet (group C, ether extract 2.6%) or a diet containing vegetable fat (group V, ether extract, 9.9%) or animal fat (group A, ether extract 11.7%). A principal component (PC) analysis was performed with the variables: ultimate pH at 24 h post mortem measured in the longissimus dorsi (LD) and in the biceps femoris (BF) muscles, colour measured on the surface of the loin, fatty acid composition of perirenal fat, meat fat content of the hind leg, water holding capacity and cooking losses of the meat, and sensory variables determined by a trained panel test. The four first PC explained 62% of the total variation (27, 13, 11 and 11%, respectively). The first PC grouped the fatty acids, the second PC grouped the sensorial variables, and the third and fourth PCs grouped the pHs and the water holding capacity. The projection of the data in the first two PCs showed three separate groups of points. Animals fed with diet V were on the left side of the graph, where the variable C18:2 lies, whereas animals fed with diets A and C lay on the right side of the graph, where the saturated acids were grouped. These were slightly separated by the higher content of oleic acid in the animals fed with diet A. The second PC, where the sensorial variables were grouped, did not separate the animals fed with diets A, V and C. The diets used in this experiment had only a slight influence on the organoleptic characteristics of rabbit meat.  相似文献   
55.
Analytical methods are presented for detecting simultaneously 11 fungal metabolites (aflatoxins B1, B2, G1 and G2, citrinin, cyclopiazonic acid, mycophenolic acid, ochratoxin A, penicillic acid, penitrem A and roquefortine C) on different matrices. The methods were applied to determine the mycotoxins produced by different Penicillium crustosum, Penicillium nordicum and Penicillium verrucosum strains on yeast extract sucrose (YES) agar and cheese and bread analogues and are based on high-performance liquid chromatography (HPLC) and photodiode array detection (PDA). The growth substrate had a distinctive effect on the mycotoxin production ability of the fungi examined. The P. crustosum strains produced roquefortine C on all the substrates, with the highest amounts being detected on the cheese analogue. Penitrem A was synthesised on the cheese analogue only. The strains of P. verrucosum produced exclusively citrinin on YES, but both ochratoxin A and citrinin were detected in considerable amounts on the bread analogue. On the bread, toxin profiles varied significantly between the individual P. verrucosum strains. The cheese analogue was not favourable for the mycotoxin production of this species. The growth substrate had the least effect on the toxin production of the P. nordicum strains, which synthesised ochratoxin A in moderate amounts on all three media.  相似文献   
56.
A functional comparison of three human SAPKs with fungal Hog1p was undertaken, using Saccharomyces cerevisiae as a heterologous expression system. We characterized the role of mammalian MAP kinases in sensitivity to both osmotic and oxidative stress of a S. cerevisiae hog1 mutant. Western blot analyses indicated that S. cerevisiae can only phosphorylate mammalian MAP kinases in response to osmotic stress but not to oxidative stress, while morphogenetic defects characteristic of hog1 mutants under hyperosmotic stress are only suppressed by fungal and not mammalian Hog1p. Our data demonstrate the functional conservation of MAPKs although they also evidence differential aspects among the three human SAPKs and the fungal MAPKs.  相似文献   
57.
The effect of different enriched fibre products obtained from butternut (Cucurbita moschata Duchesne ex Poiret) on bread making and bread quality was evaluated through the study of bread yield, quality parameters (specific volume, crumb firmness, crumb and crust colour) and bread shelf life. Fractions tested were obtained from butternut mesocarp through ethanolic treatment (fraction AIR) or through dehydration (fraction S) or from the ethanolic treatment of peel (fraction C). These fractions were incorporated in a bread formula, at levels of 5, 10 and 15 g of fibre fraction per kilogram of wheat flour. The study of crumb through digital imaging and thermal analysis was also performed in order to better understand the effects observed. An important influence of water absorption kinetics and chemical composition of the fibre fractions studied was observed in the results obtained. Lower bread firmness was determined 24 h after baking when 10 g of C or either 10 or 15 g of S was present per kilogram of wheat flour used. Breads made with flour containing 10–15 g of S or 5 g of C per kilogram of wheat flour tended to be softer, while 10 g of C per kilogram of flour produced significantly softer breads along 9 days storage.  相似文献   
58.
The M1 zinc metalloproteases ERAP1, ERAP2, and IRAP play a role in HLA-I antigen presentation by refining the peptidome either in the ER (ERAP1 and ERAP2) or in the endosomes (IRAP). They have also been entrusted with other, although less defined, functions such as the regulation of the angiotensin system and blood pressure. In humans, ERAP1 and IRAP are commonly expressed. ERAP2 instead has evolved under balancing selection that maintains two haplotypes, one of which undergoing RNA splicing leading to nonsense-mediated decay and loss of protein. Hence, likewise in rodents, wherein the ERAP2 gene is missing, about a quarter of the human population does not express ERAP2. We report here that macrophages, but not monocytes or other mononuclear blood cells, express and secrete an ERAP2 shorter form independent of the haplotype. The generation of this “short” ERAP2 is due to an autocatalytic cleavage within a distinctive structural motif and requires an acidic micro-environment. Remarkably, ERAP2 “short” binds IRAP and the two molecules are co-expressed in the endosomes as well as in the cell membrane. Of note, the same phenomenon could be observed in some cancer cells. These data prompt us to reconsider the role of ERAP2, which might have been maintained in humans due to fulfilling a relevant function in its “short” form.  相似文献   
59.
Migraine is a common brain-disorder that affects 15% of the population. Converging evidence shows that migraine is associated with gastrointestinal disorders. However, the mechanisms underlying the interaction between the gut and brain in patients with migraine are not clear. In this study, we evaluated the role of the short-chain fatty acids (SCFAs) as sodium propionate (SP) and sodium butyrate (SB) on microbiota profile and intestinal permeability in a mouse model of migraine induced by nitroglycerine (NTG). The mice were orally administered SB and SP at the dose of 10, 30 and 100 mg/kg, 5 min after NTG intraperitoneal injections. Behavioral tests were used to evaluate migraine-like pain. Histological and molecular analyses were performed on the intestine. The composition of the intestinal microbiota was extracted from frozen fecal samples and sequenced with an Illumina MiSeq System. Our results demonstrated that the SP and SB treatments attenuated hyperalgesia and pain following NTG injection. Moreover, SP and SB reduced histological damage in the intestine and restored intestinal permeability and the intestinal microbiota profile. These results provide corroborating evidence that SB and SP exert a protective effect on central sensitization induced by NTG through a modulation of intestinal microbiota, suggesting the potential application of SCFAs as novel supportive therapies for intestinal disfunction associated with migraine.  相似文献   
60.
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