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81.
Scope : Decreasing postprandial glycaemic excursions may have a beneficial effect on inflammatory and oxidative stress profiles. In this study, we investigated the impact of carbohydrate digestibility modulation per se, as a means of reducing the glycaemic response, on metabolic and inflammatory responses in subjects with metabolic risk factors. Methods and results : Twenty healthy subjects with metabolic risk consumed a cereal product either high in Slowly Digestible Starch (HSDS) or low in SDS (LSDS) at breakfast daily for 3 weeks, in a cross‐over design. Following each 3‐week session, postprandial glycaemia, insulinaemia, the lipid profile, inflammation and oxidative stress markers were assessed and compared to those induced by ingestion of a glucose solution (as a reference). The 2‐h glycaemic and insulinaemic responses were significantly lower following the HSDS breakfast compared with the LSDS breakfast or glucose. No significant differences between the products were observed in terms of the lipid profile, C‐reactive protein, IL‐6 and tumour necrosis factor alpha. We observed a slight increase in fasting lipid peroxidation markers, including an increase in plasma malondialdehyde (MDA) and a decrease in whole blood glutathione (GSH), without significant alteration of urinary F2‐isoprostanes or plasma glutathione peroxidase (GPx) activity. Conclusion : Consumption of HSDS products for 3 weeks significantly altered both postprandial glycaemia and insulinaemia, but was not sufficient to modify the inflammatory profile. Consumption of both cereal products was associated with a slightly higher fasting oxidative stress profile.  相似文献   
82.
ABSTRACT:  The study was carried out to evaluate the effects of gamma-irradiation alone or in combination with oregano essential oil on murein composition of  Staphylococcus aureus  and on the intracellular and extracellular concentration of ATP. The bacterial strain was treated with 3 irradiation doses: 1.2 kGy to induce cell damage, 2.9 kGy to obtain a viable but nonculturable state, and 3.5 kGy to cause cell death. Oregano essential oil was used at 0.010% and 0.013% (w/v), which is the minimum inhibitory concentration (MIC). All treatments had a significant effect ( P  ≤ 0.05) on the murein composition, although some muropeptides did not seem to be affected by the treatment. Each treatment influenced differently the relative percentage and number of muropeptides. There was a significant ( P  ≤ 0.05) correlation between the reduction of intracellular ATP and increase in extracellular ATP following treatment of the cells with oregano oil. The reduction of intracellular ATP was even more important when essential oil was combined with irradiation. Also, irradiation alone of  S. aureus  induced a significant decrease ( P  ≤ 0.05) of the internal ATP and a significant increase ( P  ≤ 0.05) of the external ATP. However, no significant difference ( P  > 0.05) was observed in ATP concentrations between different radiation doses. Transmission electron microscopic observation revealed that oregano oil and irradiation have an effect on cell wall structure.  相似文献   
83.
Whether neurosteroids regulate the synthesis of long chain polyunsaturated fatty acids in brain cells is unknown. We examined the influence of 17-β-estradiol (E2) on the capacity of SH-SY5Y cells supplemented with α-linolenic acid (ALA), to produce eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA). Cells were incubated for 24 or 72 h with ALA added alone or in combination with E2 (ALA + E2). Fatty acids were analyzed by gas chromatography of ethanolamine glycerophospholipids (EtnGpl) and phosphatidylcholine (PtdCho). Incubation for 24 h with ALA alone increased EPA and DPA in EtnGpl, by 330 and 430% compared to controls (P < 0.001) and DHA by only 10% (P < 0.05). Although DHA increased by 30% (P < 0.001) in ALA + E2-treated cells, the difference between the ALA and ALA + E2 treatments were not significant after 24 h (Anova-1, Fisher’s test). After 72 h, EPA, DPA and DHA further increased in EtnGpl and PtdCho of cells supplemented with ALA or ALA + E2. Incubation for 72 h with ALA + E2 specifically increased EPA (+34% in EtnGpl, P < 0.001) and DPA (+15%, P < 0.001) compared to ALA alone. Thus, SH-SY5Y cells produced membrane EPA, DPA and DHA from supplemental ALA. The formation of DHA was limited, even in the presence of E2. E2 significantly favored EPA and DPA production in cells grown for 72 h. Enhanced synthesis of ALA-elongation products in neuroblastoma cells treated with E2 supports the hypothesis that neurosteroids could modulate the metabolism of PUFA.  相似文献   
84.
Project portfolio management offices (PPMOs) are a subset of project management offices (PMOs) that handle collections of multiple single projects and programmes, i.e. portfolios. PPMOs are centralised organisational units that cater to the demands of various stakeholders by performing specialised tasks. They are initiated by their organisation's leadership in response to increasing management challenges originating from project portfolios. Although there has been considerable research on PMOs in general, not only a clear understanding of multi-project PMOs' activity patterns set in specific contexts like project portfolio management, but also both existence and mode of multi-project PMOs' contribution to successful performance are still lacking. By quantitatively analysing PPMOs in 278 portfolios, we identify three different activity patterns, which are interpreted as distinctive roles. We show a significant positive effect of PPMOs' coordinating and controlling roles on performance in terms of project portfolio management quality, which is a predictor of portfolio success.  相似文献   
85.
Lactobacillus sakei is a meat-borne lactic acid bacterium species exhibiting a wide genomic diversity. We have investigated the diversity of response to various oxidative compounds, between L. sakei strains, among a collection representing the genomic diversity. We observed various responses to the different compounds as well as a diversity of response depending on the aeration conditions used for cell growth. A principal component analysis revealed two main phenotypic groups, partially correlating with previously described genomic clusters. We designed strains mixes composed of three different strains, in order to examine the behavior of each strain, when cultured alone or in the presence of other strains. The strains composing the mixtures were chosen as diverse as possible, i.e. exhibiting diverse responses to oxidative stress and belonging to different genomic clusters. Growth and survival rates of each strain were monitored under various aeration conditions, with or without heme supplementation. The results obtained suggest that some strains may act as “helper” or “burden” strains depending on the oxidative conditions encountered during incubation. This study confirms that resistance to oxidative stress is extremely variable within the L. sakei species and that this property should be considered when investigating starter performance in the complex meat bacterial ecosystems.  相似文献   
86.
Methylcellulose (MC) films were prepared by casting from its 1% aqueous solution containing 0.5% vegetable oil, 0.25% glycerol, and 0.025% Tween®80. Poly(caprolactone) (PCL) films were prepared by compression molding from its granules. Biodegradable composite films were fabricated using MC film as reinforcing agent and PCL as the matrix material by compression molding. One layer of MC film was reinforced with two layers of PCL films. The MC content in the composites was varied from 10 to 50% by weight. Mechanical, barrier, and degradation properties of PCL, MC, and composite films were evaluated. The values of puncture strength (PS), puncture deformation (PD), viscoelasticity (Y) coefficient, and water vapor permeability (WVP) of the composites (50% MC content) were found to be 124.3 N/mm, 3.2 mm, 31%, and 2.6 g·mm/m2·day·kPa, respectively. Oxygen transmission rate (OTR) of PCL, MC, and composites (50% MC) were found to be 175, 25, 22 cc/m2/d, respectively, which indicated that composite films showed significantly lower OTR than PCL films. Degradation tests of the composite films (50% MC) were performed for 6 weeks in aqueous medium (at 25°C), and it was found that composites lost its mass slowly with time. After 6 weeks, mass and PS of the composites were decreased to 13.4 and 12%, respectively. Composite interface was studied by scanning electron microscopy (SEM). The MC film had good adhesion with PCL matrix during compression molding and suggested strong interface of the composite system. SEM image after 6 weeks of degradation showed some openings in the interface and revealed slow degradation of the MC films. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
87.
Fibroblast growth factors (FGFs) are involved in paracrine control of follicle development. It was previously demonstrated that FGF10 decreases estradiol (E(2)) secretion in granulosa cell culture and that theca cell FGF10 mRNA expression is decreased in healthy follicles from abattoir ovaries. The main objectives of this study were to evaluate FGF10 and FGFR2b mRNA expression during follicular development in vivo, to evaluate the effect of FGF10 on follicle growth using Bos taurus taurus cows as a model, and to gain more insight into the mechanisms through which FGF10 inhibits steroidogenesis. Messenger RNA encoding both FGF10 and FGFR2b (main FGF10 receptor) was significantly more expressed in subordinate follicles (SFs) than in dominant follicles (DFs). The intrafollicular injection of FGF10 into the largest growing follicle at 7-8?mm in diameter interrupted the DF growth in a dose-dependent manner (11±0.4, 8.3±1 and 5.9±0.3?mm for 0, 0.1, and 1?μg/ml FGF10, respectively, at 72?h after treatment; P<0.05). In a third experiment, follicles were obtained 24?h after FGF10 (1?μg/ml) or PBS treatment through ovariectomy. In theca cells, FGF10 treatment did not affect mRNA encoding steroidogenic enzymes, LHCGR and IGFBPs, but significantly upregulated FGF10 mRNA expression. The expression of CYP19A1 mRNA in granulosa cells was downregulated by FGF10 treatment, which was accompanied by a 50-fold decrease in E(2) production, and decreased cyclin D2 mRNA. These results have shown that FGF10 and its receptor FGFR2b are more expressed in SFs and provide solid in vivo evidence that FGF10 acts as an important regulator of follicular growth in cattle.  相似文献   
88.
The use of dietary supplements is increasing globally and this includes the use of plant food supplements (PFS). A variety of factors may be influencing this increased consumption including the increasing number of older people in society, mistrust in conventional medicine and the perception that natural is healthy. Consumer studies in this area are limited, with a focus on dietary supplements in general, and complicated by the use of certain plant food supplements as herbal medicines. Research indicates that higher use of dietary supplements has been associated with being female, being more educated, having a higher income, being white and being older, however the drivers for consumption of supplements are complex, being influenced by both demographic and health-related factors. The aim of this paper is to provide an overview of current knowledge about the users and the determinants of usage of plant food supplements. With growing consumption of these products, the need for effective risk-benefit assessment becomes ever more important and an insight into who uses these types of products and why is an important starting point for any future science-based decisions made by policy makers, PFS manufacturers and ultimately by consumers themselves.  相似文献   
89.
One of the main challenges in food contact materials research is to prove that the presence of non-intentionally added substances (NIAS) is not a safety issue. Migration extracts may contain many unknown substances present at low concentrations. It is difficult and time-consuming to identify all these potential NIAS and concurrently to assess their health risk upon exposure, whereas the health relevance at low exposure levels might not even be an issue. This paper describes a scientifically based, but pragmatic safety assessment approach for unknown substances present at low exposure levels in food contact matrices. This complex mixture safety assessment strategy (CoMSAS) enables one to distinguish toxicologically relevant from toxicologically less relevant substances, when related to their respective levels of exposure, and allows one to focus on the substances of potential health concern. In particular, substances for which exposure will be below certain thresholds may be considered not of health relevance in case specific classes of substances are excluded. This can reduce the amount of work needed for identification, characterisation and evaluation of unknown substances at low concentration. The CoMSAS approach is presented in this paper using a safety assessment of unknown NIAS that may migrate from three carton samples.  相似文献   
90.
Efforts to link media use to adolescents' sexual initiation have produced somewhat inconsistent results, perhaps as a result of the limited framing of the question. This study sought to expand current approaches by sampling college students instead of high school students, by investigating a range of sexual behaviors and media formats, and by testing a model that featured sexual cognitions as mediators. We tested our model with a sample of 796 heterosexual, male college students who reported on their regular consumption of 4 media (prime-time TV programs, music videos, movies, and men's magazines); their attitudes toward abstinence, the male sexual role, and nonrelational sex; their perceptions of peer sexual behavior; and several aspects of their sexual behavior (e.g., number of sexual partners). Findings revealed strong support for our mediated model, with exposure to men's magazines and movies contributing most strongly to their sexual cognitions, and with men's cognitions, in turn, contributing heavily to their sexual behavior. Some direct connections from media use to sexual behavior also emerged. Together, the findings provide insight into both potential mechanisms for and new approaches to addressing this issue. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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