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101.
Trichostatin A ([R-(E,E)]-7-[4-(dimethylamino) phenyl]-N-hydroxy- 4,6-dimethyl- 7-oxo-2,4-heptadienamide, TSA) affects chromatin state through its potent histone deacetylase inhibitory activity. Interfering with the removal of acetyl groups from lysine residues in histones is one of many epigenetic regulatory processes that control gene expression. Histone deacetylase inhibition drives cells toward the differentiation stage, favoring the activation of specific genes. In this paper, we investigated the effects of TSA on H3 and H4 lysine acetylome and methylome profiling in mice embryonic stem cells (ES14), treated with trichostatin A (TSA) by using a new, untargeted approach, consisting of trypsin-limited proteolysis experiments coupled with MALDI-MS and LC-MS/MS analyses. The method was firstly set up on standard chicken core histones to probe the optimized conditions in terms of enzyme:substrate (E:S) ratio and time of proteolysis and, then, applied to investigate the global variations of the acetylation and methylation state of lysine residues of H3 and H4 histone in the embryonic stem cells (ES14) stimulated by TSA and addressed to differentiation. The proposed strategy was found in its simplicity to be extremely effective in achieving the identification and relative quantification of some of the most significant epigenetic modifications, such as acetylation and lysine methylation. Therefore, we believe that it can be used with equal success in wider studies concerning the characterization of all epigenetic modifications.  相似文献   
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Nutritional status in patients with neuroendocrine tumours (NETs), especially of gastroenteropancreatic origin, can be deeply affected by excessive production of gastrointestinal hormones, peptides, and amines, which can lead to malabsorption, diarrhoea, steatorrhea, and altered gastrointestinal motility. Besides, the surgical and/or medical management of NETs can lead to alteration of gastrointestinal secretory, motor, and absorptive functions, with both dietary and nutritional consequences. Indeed, disease-related malnutrition is a frequently encountered yet both underrecognized and understudied clinical phenomenon in patients with NETs, with substantial prognostic and socioeconomic consequences. Most of these conditions can be alleviated by a tailored nutritional approach, also with the aim of improving the efficacy of cancer treatments. In this setting, skilled nutritionists can play a fundamental role in the multidisciplinary health care team in NETs management and their presence should be recommended. The aim of this review is to provide dietary advices for each specific condition in patients with NETs, underlining the importance of a nutritional approach to treat malnutrition in this setting. Further, we will provide preliminary evidence coming from our data on the assessment of nutritional status in a single cohort of patients with NETs.  相似文献   
104.
In-group favoritism in the minimal group setting was hypothesized to be a function of 2 processes: a tendency to base in-group judgments on the self (self-anchoring) and a tendency to assume 1 group to be the opposite of the other (differentiation). In the first 3 experiments, in which the order of rating the self and target group was varied, categorized and uncategorized participants were given trait information about 1 group and were asked to estimate the level of those traits in the other group. In-group judges tended to base group ratings on the self, whereas out-group and uncategorized judges inferred the 2 groups to be opposite of one another. Experiment 4 attempted to directly assess the direction of inference between self and in-group by giving feedback about self or in-group on unfamiliar dimensions and found that participants were more willing to generalize from self to in-group than from in-group to self. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
The local stability properties of the collocation method applied to a second kind Volterra integral equation with degenerate kernel are investigated. A finite length recurrence relation is derived and theorems for the local stability of the methods are proved.  相似文献   
106.
Introduction: During hemodialysis (HD) the interaction of the blood with the dialyzer triggers both an inflammatory reaction and an activation of the coagulation cascade. An accepted parameter to quantify the extent of coagulation activation during HD is not available. This study aims to evaluate its amplitude, comparing dialyzers made of different polysulfone polymers, by measuring D‐dimers in the filter‐rinsing fluids (Frf) and to test whether Frf D‐dimers are suitable candidate markers to assess contact coagulation activation during HD. Methods: In a prospective, cross‐over study 41 hemodialysis patients were randomly allocated to nine HD sessions with three types of polysulfone membranes: Filter A: Poliflux®RevaclearMAX; Filter B: Helixone®Fx80, Filter C: Polyflux®H210. Findings: A total of 117 HD sessions were studied. The mean (SD) filter (Frf) D‐dimers were 0.19 µg/L (0.56) for Filter A; 0.66 µg/L (2.81) for Filter B; 0.33 µg/L (1.13) for Filter C. Significant differences were found: A vs. B (P < 0.01), A vs. C (P = 0.01); B vs. C not significant. A large between‐patient variability of D‐dimer filter levels was found. D‐Dimers in blood showed a similar trend but differences were not significant. Discussion: The contact activation of coagulation during HD may also vary among filters made up with similar polysulfones. D‐dimer in the filter rinsing fluid but not in the blood can be considered a candidate marker for the evaluation of thrombogenicity during HD. Further studies are needed to elucidate the mechanism(s) and to confirm the usefulness of filter rinsing fluid D‐Dimers as a clotting activation marker during HD.  相似文献   
107.
Water Resources Management - The progressive increase of impervious surfaces induced by urbanization altered significantly the natural hydrological cycle of urban catchments. To face the need of...  相似文献   
108.
In this paper, an integrated, cognitive view of different mechanisms, reasons and pathways to norm compliance is presented. After a short introduction, theories of norm compliance are reviewed, and found to group in four main typologies: the rational choice model of norm compliance; theories based on conditional preferences to conformity, theories of thoughtless conformity, and theories of norm internalization. In the third section of the paper, the normative architecture EMIL-A is presented. Previous work discussed the epistemic module of this normative architecture, allowing for the generation of normative beliefs being formed. The fourth and fifth sections present the pragmatic modules of EMIL-A, i.e. norm adoption??leading to normative goals??and norm compliance??leading to their execution. Not only are several alternative reasons for norm adoption shown, but also several pathways to norm compliance are identified. Finally, a summary and ideas for future works conclude the paper.  相似文献   
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The objective of this study was to explore the use of near infrared (NIR) spectroscopy and chemometrics to monitor the degree of heat treatment of fish meal. Six batches of fish meal (approximately 500 g) were split in sub‐samples of 50 g and heated at constant temperature (60 ± 5 °C) for different periods of time (15 and 30 min, 1, 2, 3, 4, 5, 6, 8, 48 and 72 h) in a force air oven and scanned in the NIR region (1100–2500 nm) in a monochromator instrument in reflectance. Principal component analysis (PCA), stepwise discriminant analysis (SLDA) and partial least square regression (PLS) models were used to interpret, classify and predict the extent to heat treatment in fish meal samples. The SLDA models correctly classified 80% and 100% of fish meal samples belonging to the untreated fish meal and after 4, 5 and 6 h of heat treatment. However, samples heated for 30 min, 1, 2 and 3 h yield poor classification rates (less than 50%). This study demonstrated the potential ability of NIR spectroscopy to predict and classify the extent of heat treatment during the production of fish meal. However, further research must carry out in order to validate the NIR calibrations to predict the degree of heat treatment in fish meal expose to a shorter time.  相似文献   
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