Effect of dietary protein on calpastatin in canine skeletal muscle

The cysteine proteinases, μ- and m-calpain, along with their inhibitor, calpastatin, have been hypothesized to play a role in skeletal muscle protein degradation. Because nutrition has previously been shown to influence the expression of calpastatin, the working hypothesis of this study was that the quantity and source of dietary protein could influence regulation of the calpain system in muscle. The objectives to support this hypothesis were to determine the effects of dietary protein (amount and source) on the expression of calpastatin in canine skeletal muscle. This study comprised eight diets with seven dogs per diet. A biopsy was taken from the biceps femoris of all 56 dogs before and after 10 wk on their respective diets. This experimental design allowed examination of change within individual dogs. Diets 1 to 4 contained 12% total protein derived from chicken and/or corn gluten meal in ratios of 100:0, 67:33, 33:67, and 0:100%, respectively. Diets 5 to 8 contained 28% total protein with protein sources and ratios identical to Diets 1 to 4. Differences in calpastatin were examined qualitatively using SDS-PAGE and immunoblotting, and semiquantitatively with densitometric analyses. The majority of the calpastatin blots showed three distinct calpastatin bands, the uppermost appearing at approximately 110 kDa. Diet 5 (28% CP, 100% chicken) resulted in an increase in the expression of the 110-kDa calpastatin band compared with the other two lower molecular weight bands in the same samples. Muscle from dogs fed Diet 5 showed greater increase in (P \u3c 0.05) calpastatin intensity of the topmost band than those fed Diet 8 (0:100; chicken:corn gluten meal). Diet 5 (100:0; chicken:corn gluten meal) showed greater total calpastatin intensity than Diet 8 (0:100; chicken: corn gluten meal). These data suggest that dogs fed a diet containing a higher total percentage of chicken protein may have a greater potential to regulate calpain-mediated degradation of muscle protein than dogs fed diets containing corn gluten meal

Effects of available dietary carbohydrate and preslaughter treatment on glycolytic potential, protein degradation, and quality traits of pig muscles

The current study was conducted to determine the interactive effects of a glycogen-reducing diet fed to finishing pigs and length of preslaughter transportion on muscle metabolic traits, proteolysis of intermediate filament and costameric proteins, and meat quality traits. Large White gilts and barrows (n = 48) were selected at 88 kg of BW and individually fed for 21 d a diet (2.6 kg/d) either high (HC) or low (LC) in available carbohydrates. Six gilts and 6 barrows fed the HC and LC diets were subjected to 0 or 3 h of transportation on the day of slaughter. Muscle temperature and pH were measured at 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, and 24 h postmortem in the LM and 24 h postmortem in the dark (STD) and light (STL) portion of the semitendinosus. At 24 h postmortem, glycolytic potential (GP) was determined in the LM, STD, and STL, as well as proteolysis of titin, nebulin, desmin, vinculin, and talin in the LM and STD. The GP was lower (P \u3c 0.05) in muscles from LC-pigs than in muscles from HC-pigs. The LC diet also resulted in lower (P \u3c 0.05) pH, and a darker (P = 0.03), less (P \u3c 0.01) yellow color in the STL. The LC diet decreased (P = 0.04) cooking losses in the STL and STD. The 3-h journey further decreased (P = 0.05) the GP in the STD, regardless of the diet, but transport had no effect (P ≥ 0.67) on the GP of the LM and STL. Ultimate pH of the LM was lower (P = 0.02), and both portions of the semitendinosus were darker (P = 0.01) and less yellow (P \u3c 0.01), in pigs transported 3 vs. 0 h. In pigs transported for 3 h, intact vinculin tended to be more (P = 0.08) degraded in the LM, which coincided with lower (P = 0.04) drip losses in the LM of pigs transported for 3 compared with 0 h. Increased (P \u3c 0.01) proteolysis of titin paralleled lower (P = 0.02) shear force values in the STD of pigs transported 3 vs. 0 h. Although the present results demonstrated the potential of a glycogen-reducing diet to alter the GP of different porcine muscles, the effect of these changes on meat quality traits was limited to higher ultimate pH and darker color in the STL. The positive effects of length of transportation on water-holding capacity (LM and STD) and meat color (STD and STL) were only partially related to the resting muscle glycogen concentration because the 3-h transport lowered the GP only in the muscle with the lowest basal glycogen concentration

Electron shielding studies - Experimental program Technical summary report, 1 Aug. 1968 - 31 Dec. 1969

Electron shielding and bremsstrahlung energy spectra for tin, gold, and silve

Characterisation of the transmissivity field of a fractured and karstic aquifer, Southern France

International audienceGeological and hydrological data collected at the Terrieu experimental site north of Montpellier, in a confined carbonate aquifer indicates that both fracture clusters and a major bedding plane form the main flow paths of this highly heterogeneous karst aquifer. However, characterising the geometry and spatial location of the main flow channels and estimating their flow properties remain difficult. These challenges can be addressed by solving an inverse problem using the available hydraulic head data recorded during a set of interference pumping tests.We first constructed a 2D equivalent porous medium model to represent the test site domain and then employed regular zoning parameterisation, on which the inverse modelling was performed. Because we aim to resolve the fine-scale characteristics of the transmissivity field, the problem undertaken is essentially a large-scale inverse model, i.e. the dimension of the unknown parameters is high. In order to deal with the high computational demands in such a large-scale inverse problem, a gradient-based, non-linear algorithm (SNOPT) was used to estimate the transmissivity field on the experimental site scale through the inversion of steady-state, hydraulic head measurements recorded at 22 boreholes during 8 sequential cross-hole pumping tests. We used the data from outcrops, borehole fracture measurements and interpretations of inter-well connectivities from interference test responses as initial models to trigger the inversion. Constraints for hydraulic conductivities, based on analytical interpretations of pumping tests, were also added to the inversion models. In addition, the efficiency of the adopted inverse algorithm enables us to increase dramatically the number of unknown parameters to investigate the influence of elementary discretisation on the reconstruction of the transmissivity fields in both synthetic and field studies.By following the above approach, transmissivity fields that produce similar hydrodynamic behaviours to the real head measurements were obtained. The inverted transmissivity fields show complex, spatial heterogeneities with highly conductive channels embedded in a low transmissivity matrix region. The spatial trend of the main flow channels is in a good agreement with that of the main fracture sets mapped on outcrops in the vicinity of the Terrieu site suggesting that the hydraulic anisotropy is consistent with the structural anisotropy. These results from the inverse modelling enable the main flow paths to be located and their hydrodynamic properties to be estimated

Reproducing the 'national home': gendering domopolitics

Walters developed the concept of domopolitics to refer to the ways in which the securitisation of migration contributes to the construction of the UK as a ‘national home’. Domopolitical policies and discourses produce the UK as the ‘national home’ of ‘neoliberal citizens’; they thus serve as tools of neoliberal governmentality, disciplining both citizens and migrants into displaying qualities associated with neoliberal citizenship, especially economic productivity. However, the concept of ‘home’ has a particular genealogy within liberal discourses of citizenship. As Pateman contends, the political ‘public’ sphere of liberal citizenship is constructed in opposition to an apolitical ‘private’ sphere. The public sphere has been coded as the domain of men, while women have been relegated to the private ‘home’. Consequently, women have been deemed responsible for the reproduction of both the private, and the ‘national’ home, a construction which has persisted under neoliberalism. While often superficially gender-neutral, domopolitics actually relies upon, and reinforces, these gendered understandings of neoliberal citizenship. Domopolitical policies and discourses construct migrant women’s reproductive practices as a legitimate and necessary site of state intervention, disciplining migrant women to ensure they ‘correctly’ reproduce the neoliberal ‘national home.

Prospects of light sterile neutrino oscillation and CP violation searches at the Fermilab Short Baseline Neutrino Facility

We investigate the ability of the short baseline neutrino (SBN) experimental program at Fermilab to test the globally-allowed (3 þ N) sterile neutrino oscillation parameter space. We explicitly consider the globally-allowed parameter space for the (3 þ 1), (3 þ 2), and (3 þ 3) sterile neutrino oscillation scenarios. We find that SBN can probe with 5σ sensitivity more than 85%, 95% and 55% of the parameter space currently allowed at 99% confidence level for the (3 þ 1), (3 þ 2) and (3 þ 3) scenarios, respectively, with the (3 þ N) allowed space used in these studies closely resembling that of previous studies [J. M. Conrad, C. M. Ignarra, G. Karagiorgi, M. H. Shaevitz, and J. Spitz, Adv. High Energy Phys. 2013, 1 (2013).], calculated using the same methodology. In the case of the (3 þ 2) and (3 þ 3) scenarios, CP-violating phases appear in the oscillation probability terms, leading to observable differences in the appearance probabilities of neutrinos and antineutrinos. We explore SBN’s sensitivity to those phases for the (3 þ 2) scenario through the currently planned neutrino beam running, and investigate potential improvements through additional antineutrino beam running. We show that, if antineutrino exposure is considered, for maximal values of the (3 þ 2) CP-violating phase ϕ54, SBN could be the first experiment to directly observe ∼2σ hints of CP violation associated with an extended lepton sector

The effect of exogenous glucose infusion on early embryonic development in lactating dairy cows

peer-reviewedThe objective of this study was to examine the effect of intravenous infusion of glucose on early embryonic development in lactating dairy cows. Nonpregnant, lactating dairy cows (n = 12) were enrolled in the study (276 ± 17 d in milk). On d 7 after a synchronized estrus, cows were randomly assigned to receive an intravenous infusion of either 750 g/d of exogenous glucose (GLUC; 78 mL/h of 40% glucose wt/vol) or saline (CTRL; 78 mL/h of 0.9% saline solution). The infusion period lasted 7 d and cows were confined to metabolism stalls for the duration of the study. Coincident with the commencement of the infusion on d 7 after estrus, 15 in vitro-produced grade 1 blastocysts were transferred into the uterine horn ipsilateral to the corpus luteum. All animals were slaughtered on d 14 to recover conceptuses, uterine fluid, and endometrial tissue. Glucose infusion increased circulating glucose concentrations (4.70 ± 0.12 vs. 4.15 ± 0.12 mmol/L) but did not affect milk production or dry matter intake. Circulating β-hydroxybutyrate concentrations were decreased (0.51 ± 0.01 vs. 0.70 ± 0.01 mmol/L for GLUC vs. CTRL, respectively) but plasma fatty acids, progesterone, and insulin concentrations were unaffected by treatment. Treatment did not affect either uterine lumen fluid glucose concentration or the mRNA abundance of specific glucose transporters in the endometrium. Mean conceptus length, width, and area on d 14 were reduced in the GLUC treatment compared with the CTRL treatment. A greater proportion of embryos in the CTRL group had elongated to all length cut-off measurements between 11 and 20 mm (measured in 1-mm increments) compared with the GLUC treatment. In conclusion, infusion of glucose into lactating dairy cows from d 7 to d 14 post-estrus during the critical period of conceptus elongation had an adverse impact on early embryonic development

Partial Purification of Peroxiredoxin-2 From Porcine Skeletal Muscle

Fresh meat quality is adversely affected by protein oxidation. However, a fundamental understanding of the diverse factors that influence protein oxidation in postmortem muscle remains elusive. Peroxiredoxin-2 (Prdx2), an antioxidant protein, is more abundant in tough meat based on instrumental tenderness; however, the role of Prdx2 in postmortem skeletal muscle is unknown. Therefore, the objective was to develop a method to purify Prdx2 from the diaphragm, psoas major, and longissimus lumborum. Proteins soluble at low ionic strength were extracted, dialyzed, clarified, and loaded onto a Q-Sepharose anion exchange column equilibrated with TEM (pH 7.4). In all preparations, Prdx2 eluted between about 75 and 115 mM NaCl. Immunoreactive fractions were dialyzed against TEM (pH 8.0), clarified, and loaded onto a DEAE-650S anion exchange column. In all preparations, Prdx2 eluted between approximately 55 and 75 mM NaCl. Immunoreactive fractions were concentrated and loaded onto a Superose-12 size exclusion column. Prdx2 was detected between 14 and 16 mL, and these fractions were concentrated and reduced with 0.5% 2-mercaptoethanol. A final pass over the Superose-12 column was conducted, and Prdx2 was detected in 2 peaks from 11–12 mL and 15–16 mL. Fractions 15–16 were pooled and retained for further experiments. The elution profile of Prdx2 in all 3 muscles was similar. The iden- tification of the primary protein was confirmed with liquid chromatography with tandem mass spectrometry. The purity of Prdx2 off the final Superose-12 column was approximately 33%, 52%, and 47% pure in the diaphragm, psoas major, and longissimus lumborum, respectively. This is the first report of a method to partially purify Prdx2 from skeletal muscle

Run-in periods and clinical outcomes of antipsychotics in dementia:A meta-epidemiological study of placebo-controlled trials

PURPOSE: Run-in periods are used to identify placebo-responders and washout. Our aim was to assess the association of run-in periods with clinical outcomes of antipsychotics in dementia. METHODS: We searched randomized placebo-controlled trials of conventional and atypical antipsychotics for neuropsychiatric symptoms (NPS) in dementia in electronic sources and references of selected articles. We extracted (a) the presence of a run-in period, use of placebo/investigated drug during run-in (versus washout only), and run-in duration (1 week or more) and (b) the reduction in NPS, number of participants with somnolence, extrapyramidal symptoms (EPS), and deaths per treatment group. We pooled clinical outcomes comparing antipsychotic and placebo groups in trials with and without run-in. RESULTS: We identified 35 trials. Twenty-nine trials used run-in. The pooled standardized mean difference in the reduction of NPS was -0.170 (95% CI, -0.227 to -0.112) in trials with run-in and -0.142 (95% CI, -0.331 to 0.047) in trials without run-in. The pooled odds ratio for somnolence was 2.8 (95% CI, 2.3-3.5) in trials with run-in and 3.5 (95% CI, 1.2-10.7) in trials without run-in; for EPS, these ORs were 1.8 (95% CI, 1.4-2.2) and 2.0 (95% CI, 1.3-3.1) respectively, and for mortality 1.4 (95% CI, 1.0-2.0) and 1.6 (95% CI, 0.7-3.4). The use of placebo/investigated drug during run-in and run-in duration did not affect the estimates in a consistent way. CONCLUSIONS: The use of run-in in trials might have led to overestimated efficacy and especially underestimated risks of side effects of antipsychotics compared with placebo for NPS in dementia

Review of Postmortem Protein Oxidation in Skeletal Muscle and the Role of the Peroxiredoxin Family of Endogenous Antioxidants

The development of fresh meat quality is dictated by biochemical changes during the perimortem and postmortem period. Lipid and protein oxidation in postmortem skeletal muscle and meat products is detrimental to product quality. The mechanisms that influence lipid and protein oxidation in fresh meat remain unelucidated. Peroxiredoxins are thiol-specific antioxidant proteins that are highly reactive and abundant and may be involved in limiting oxidation early postmortem. This review aims to provide a background on oxidation in skeletal muscle, peroxiredoxins, a summary of proteomic experiments associating peroxiredoxins and meat quality, and the importance of context from proteomic methods and results. Additional controlled experiments considering the cellular conditions of postmortem skeletal muscle are necessary to further understand the contribution of peroxiredoxins to fresh meat quality development