Comparative Characterization of Gluten and Hydrolyzed Wheat Proteins

Hydrolyzed wheat proteins (HWPs) are widely used as functional ingredients in foods and cosmetics, because of their emulsifying and foaming properties. However, in individuals suffering from celiac disease or wheat allergy, HWPs may have a modified immunoreactivity compared to native gluten due to changes in molecular structures. Although a variety of HWPs are commercially available, there are no in-depth comparative studies that characterize the relative molecular mass (M$_{r}$) distribution, solubility, and hydrophilicity/hydrophobicity of HWPs compared to native gluten. Therefore, we aimed to fill this gap by studying the above characteristics of different commercial HWP and gluten samples. Up to 100% of the peptides/proteins in the HWP were soluble in aqueous solution, compared to about 3% in native gluten. Analysis of the Mr distribution indicated that HWPs contained high percentages of low-molecular-weight peptides/proteins and also deamidated glutamine residues. We also found considerable differences between the seven HWPs studied, so that each HWP needs to be studied in detail to help explain its potential immunoreactivit

Bitter Compounds Decrease Gastric Emptying and Influence Intestinal Nutrient Transport

The effect of bitter tasting compounds on gastric emptying and nutrient transport from the intestine was studied using in vivo and ex vivo models. Sixteen pigs were fed a diet containing the bitter compound phenylthiocarbamide (PTC). The animals were euthanized 45 minutes postprandially and gastric contents were measured to quantify the gastric retention. Additionally, freshly isolated small intestines were mounted into modified Ussing chambers to study the effects of PTC on ex vivo nutrient transport. In summary, bitter compounds decreased the gastric emptying in vivo and increased the nutrient transport ex vivo. Further, cell culture studies identified that bitter compounds might exert their action through stimulating the secretion of the intestinal hormone cholecystokinin (CCK) from the enteroendocrine cells by increasing the intracellular calcium concentrations. Altogether, these data suggest that bitter compounds regulate feed intake and nutrient transport

Dietary oil composition differentially modulates intestinal endotoxin transport and postprandial endotoxemia

Background: Intestinal derived endotoxin and the subsequent endotoxemia can be considered major predisposing factors for diseases such as atherosclerosis, sepsis, obesity and diabetes. Dietary fat has been shown to increase postprandial endotoxemia. Therefore, the aim of this study was to assess the effects of different dietary oils on intestinal endotoxin transport and postprandial endotoxemia using swine as a model. We hypothesized that oils rich in saturated fatty acids (SFA) would augment, while oils rich in n-3 polyunsaturated fatty acids (PUFA) would attenuate intestinal endotoxin transport and circulating concentrations. Methods: Postprandial endotoxemia was measured in twenty four pigs following a porridge meal made with either water (Control), fish oil (FO), vegetable oil (VO) or coconut oil (CO). Blood was collected at 0, 1, 2, 3 and 5 hours postprandial and measured for endotoxin. Furthermore, ex vivo ileum endotoxin transport was assessed using modified Ussing chambers and intestines were treated with either no oil or 12.5% (v/v) VO, FO, cod liver oil (CLO), CO or olive oil (OO). Ex vivo mucosal to serosal endotoxin transport permeability (Papp) was then measured by the addition of fluorescent labeled-lipopolysaccharide. Results: Postprandial serum endotoxin concentrations were increased after a meal rich in saturated fatty acids and decreased with higher n-3 PUFA intake. Compared to the no oil control, fish oil and CLO which are rich in n-3 fatty acids reduced ex vivo endotoxin Papp by 50% (P \u3c 0.05). Contrarily, saturated fatty acids increased the Papp by 60% (P = 0.008). Olive and vegetable oils did not alter intestinal endotoxin Papp. Conclusion: Overall, these results indicate that saturated and n-3 PUFA differentially regulate intestinal epithelial endotoxin transport. This may be associated with fatty acid regulation of intestinal membrane lipid raft mediated permeability

Synthetic spectra of H Balmer and HeI absorption lines. I: Stellar library

We present a grid of synthetic profiles of stellar H Balmer and HeI lines at optical wavelengths with a sampling of 0.3 A. The grid spans a range of effective temperature 4000 K < Teff < 50000 K, and gravity 0.0 < log g < 5.0 at solar metallicity. For Teff > 25000 K, NLTE stellar atmosphere models are computed using the code TLUSTY (Hubeny 1988). For cooler stars, Kurucz (1993) LTE models are used to compute thesynthetic spectra. The grid includes the profiles of the high-order hydrogen Balmer series and HeI lines for effective temperatures and gravities that have not been previously synthesized. The behavior of H8 to H13 and HeI 3819 with effective temperature and gravity is very similar to that of the lower terms of the series (e.g. Hb) and the other HeI lines at longer wavelengths; therefore, they are suited for the determination of the atmospheric parameters of stars. These lines are potentially important to make predictions for these stellar absorption features in galaxies with active star formation. Evolutionary synthesis models of these lines for starburst and post-starburst galaxies are presented in a companion paper. The full set of the synthetic stellar spectra is available for retrieval at our website http://www.iaa.es/ae/e2.html and http://www.stsci.edu/science/starburst/ or on request from the authors at [email protected]: To be published in ApJS. 28 pages and 12 figure

Postprandial serum endotoxin in healthy humans is modulated by dietary fat in a randomized, controlled, cross-over study

Background: High-fat diets may contribute to metabolic disease via postprandial changes in serum endotoxin and inflammation. It is unclear how dietary fat composition may alter these parameters. We hypothesized that a meal rich in n-3 (ω3) fatty acids would reduce endotoxemia and associated inflammation but a saturated or n-6 (ω6) fatty acid-rich meal would increase postprandial serum endotoxin concentrations and systemic inflammation in healthy adults. Methods: Healthy adults (n = 20; mean age 25 ± 3.2 S.D. years) were enrolled in this single-blind, randomized, cross-over study. Participants were randomized to treatment and reported to the laboratory, after an overnight fast, on four occasions separated by at least one week. Participants were blinded to treatment meal and consumed one of four isoenergetic meals that provided: 1) 20 % fat (control; olive oil) or 35 % fat provided from 2) n-3 (ω3) (DHA = 500 mg; fish oil); 3) n-6 (ω6) (7.4 g; grapeseed oil) or 4) saturated fat (16 g; coconut oil). Baseline and postprandial blood samples were collected. Primary outcome was defined as the effect of treatment meal on postprandial endotoxemia. Serum was analyzed for metabolites, inflammatory markers, and endotoxin. Data from all 20 participants were analyzed using repeated-measures ANCOVA. Results: Participant serum endotoxin concentration was increased during the postprandial period after the consumption of the saturated fat meal but decreased after the n-3 meal (p  0.05). There was no treatment meal effect on participant postprandial serum biomarkers of inflammation. Postprandial serum triacylglycerols were significantly elevated following the n-6 meal compared to the n-3 meal. Non-esterified fatty acids were significantly increased after consumption of the saturated fat meal compared to other treatment meals. Conclusions: Meal fatty acid composition modulates postprandial serum endotoxin concentration in healthy adults. However, postprandial endotoxin was not associated with systemic inflammation in vivo. Trial registration: This study was retrospectively registered at clinicaltrials.gov as NCT02521779 on July 28, 2015

Effects of Heat Stress and Plane of Nutrition on Production and Metabolism in Growing Pigs

We heat-stressed growing pigs and evaluated the differential effects of environmental hyperthermia and reduced feed intake. Our results indicate that hyperthermia directly effects production and metabolism and many of these are independent of reduced nutrient intake. Identifying how and why heat stress alters metabolism and physiology are prerequisites in developing ameliorating strategies to prevent the reduction in performance and lost income typically observed during the warm summer months

Three-dimensional Models of Core-collapse Supernovae From Low-mass Progenitors With Implications for Crab

We present 3D full-sphere supernova simulations of non-rotating low-mass (~9 Msun) progenitors, covering the entire evolution from core collapse through bounce and shock revival, through shock breakout from the stellar surface, until fallback is completed several days later. We obtain low-energy explosions [~(0.5-1.0)x 10^{50} erg] of iron-core progenitors at the low-mass end of the core-collapse supernova (LMCCSN) domain and compare to a super-AGB (sAGB) progenitor with an oxygen-neon-magnesium core that collapses and explodes as electron-capture supernova (ECSN). The onset of the explosion in the LMCCSN models is modelled self-consistently using the Vertex-Prometheus code, whereas the ECSN explosion is modelled using parametric neutrino transport in the Prometheus-HOTB code, choosing different explosion energies in the range of previous self-consistent models. The sAGB and LMCCSN progenitors that share structural similarities have almost spherical explosions with little metal mixing into the hydrogen envelope. A LMCCSN with less 2nd dredge-up results in a highly asymmetric explosion. It shows efficient mixing and dramatic shock deceleration in the extended hydrogen envelope. Both properties allow fast nickel plumes to catch up with the shock, leading to extreme shock deformation and aspherical shock breakout. Fallback masses of <~5x10^{-3} Msun have no significant effects on the neutron star (NS) masses and kicks. The anisotropic fallback carries considerable angular momentum, however, and determines the spin of the newly-born NS. The LMCCSNe model with less 2nd dredge-up results in a hydrodynamic and neutrino-induced NS kick of >40 km/s and a NS spin period of ~30 ms, both not largely different from those of the Crab pulsar at birth.Comment: 47 pages, 27 figures, 6 tables; minor revisions, accepted by MNRA

Constraining relativistic models through heavy ion collisions

Relativistic models can be successfully applied to the description of compact star properties in nuclear astrophysics as well as to nuclear matter and finite nuclei properties, these studies taking place at low and moderate temperatures. Nevertheless, all results are model dependent and so far it is unclear whether some of them should be discarded. Moreover, in the regime of hot hadronic matter very few calculations exist using these relativistic models, in particular when applied to particle yields in heavy ion collisions. In the present work we comment on the known constraints that can help the selection of adequate models in this regime and investigate the main differences that arise when the particle production during a Au+Au collision at RHIC is calculated with different models.Comment: 9 pages, 1 figure, 3 table

Hypoxia exacerbates heat stress effects on the porcine intestinal epithelium in vitro

Heat stress (HS) negatively impacts human health, as well as animal agriculture. The mechanisms underlying HS-induced intestinal dysfunction in vivo are still not fully elucidated. However, HS has been shown to cause intestinal ischemia/hypoxia, which contributes to reduced barrier integrity. The objective of this study was to examine hypoxia alone, HS alone, and a combination using IPEC-J2 cells. We hypothesized that hypoxia is a critical factor and important step in the pathway to HS-induced barrier dysfunction. Porcine IPEC-J2 cells were grown in Transwell™ plates and then treated either under thermal neutral (TN; 38°C) or heat stress (HS; 42°C) and either normoxia (NX; ~21% O2) or hypoxia (HX; 1% O2) conditions for 24 h. Transepithelial electrical resistance, paracellular permeability marker, FITC-dextran, media interleukin 8, cell HSP70 and 90, CLDN4, ZO-1, and EEA1 were all analyzed. Results showed that HS did not increase intestinal permeability in this model and elicited a reduction in IL-8 while still exhibiting a robust HSP response. In this model, hypoxia was required to induce intestinal barrier dysfunction and TJ redistribution. The combination of HS and hypoxia caused even more severe tight junction disruption. This was accompanied by the absence of an IL-8 response under HS