151 research outputs found

    L-Arginine Intake Effect on Adenine Nucleotide Metabolism in Rat Parenchymal and Reproductive Tissues

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    L-arginine is conditionally essetcial amino acid, required for normal cell growth, protein synthesis, ammonia detoxification, tissue growth and general performance, proposed in the treatment of men sterility and prevention of male impotence. The aim of the present paper was to estimate the activity of the enzymes of adenine nucleotide metabolism: 5′-nucleotidase (5′-NU), adenosine deaminase (ADA), AMP deaminase, and xanthine oxidase (XO), during dietary intake of L-arginine for a period of four weeks of male Wistar rats. Adenosine concentration in tissues is maintained by the relative activities of the adenosine-producing enzyme, 5′-NU and the adenosine-degrading enzyme-ADA adenosine deaminase. Dietary L-arginine intake directed adenine nucleotide metabolism in liver, kidney, and testis tissue toward the activation of adenosine production, by increased 5′-NU activity and decreased ADA activity. Stimulation of adenosine accumulation could be of importance in mediating arginine antiatherosclerotic, vasoactive, immunomodulatory, and antioxidant effects. Assuming that the XO activity reflects the rate of purine catabolism in the cell, while the activity of AMP deaminase is of importance in ATP regeneration, reduced activity of XO, together with the increased AMP-deaminase activity, may suggest that adenine nucleotides are presumably directed to the ATP regenerating process during dietary L-arginine intake

    Spectroscopy, Equation Of State And Monopole Percolation In Lattice QED With Two Flavors

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    Non-compact lattice QED with two flavors of light dynamical quarks is simulated on 16416^4 lattices, and the chiral condensate, monopole density and susceptibility and the meson masses are measured. Data from relatively high statistics runs at relatively small bare fermion masses of 0.005, 0.01, 0.02 and 0.03 (lattice units) are presented. Three independent methods of data analysis indicate that the critical point occurs at β=0.225(5)\beta =0.225(5) and that the monopole condensation and chiral symmetry breaking transitions are coincident. The monopole condensation data satisfies finite size scaling hypotheses with critical indices compatible with four dimensional percolation. The best chiral equation of state fit produces critical exponents (δ=2.31\delta=2.31, βmag=0.763\beta_{mag}=0.763) which deviate significantly from mean field expectations. Data for the ratio of the sigma to pion masses produces an estimate of the critical index δ\delta in good agreement with chiral condensate measurements. In the strong coupling phase the ratio of the meson masses are Mσ2/Mρ20.35M_\sigma^2/M_\rho^2\approx 0.35, MA12/Mρ21.4M_{A_1}^2/M_\rho^2\approx 1.4 and Mπ2/Mρ20.0M_\pi^2/M_\rho^2\approx 0.0, while on the weak coupling side of the transition Mπ2/Mρ21.0M_\pi^2/M_\rho^2\approx 1.0, MA12/Mρ21.0M_{A_1}^2/M_\rho^2\approx 1.0, indicating the restoration of chiral symmetry.\footnote{\,^{}}{August 1992}Comment: 21 pages, 24 figures (not included

    The Landau Pole at Finite Temperature

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    We study the Landau pole in the lambda phi^4 field theory at non-zero and large temperatures. We show that the position of the thermal Landau pole Lambda_L(T) is shifted to higher energies with respect to the zero temperature Landau pole Lambda_L(0). We find for high temperatures T > Lambda_L(0), Lambda_L(T) simeq pi^2 T / log (T / Lambda_L(0)). Therefore, the range of applicability in energy of the lambda phi^4 field theory increases with the temperature.Comment: LaTex, 6 pages, 2 .ps figures. Improved version. To appear in Phys. Rev. D, Rapid Communication

    Assessment of the reliability of the serbian version of the sickness impact profile questionnaire in patients with chronic viral hepatitis

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    © 2015, Serbia Medical Society. All rights reserved. SUMMARY Introduction Health-related quality of life (HRQL) of chronic patients has been researched as the ultimate goal of modern treatment of chronic diseases to improve patients’ quality of life. Objective The objective was to assess the reliability of the Serbian version of the Sickness Impact Profile (SIP) questionnaire on the sample of patients with chronic viral hepatitis. Methods The research covered 102 patients with chronic hepatitis (47 type B and 55 type C). The assessment of the reliability of the SIP questionnaire was performed by testing the internal consistency of the questions by calculating the Cronbach’s alpha coefficient. The factor analysis was used to assess whether the grouping of the questions within dimensions matches the distribution of the questions in the original English version of the questionnaire administered to U.S. patient population. Results The Cronbach’s alpha coefficient for the entire questionnaire is 0.925, 0.869 for the physical dimension, and 0.857 for the psychosocial dimension. After running a factor analysis of the psychosocial dimension, “emotional instability” was extracted as the key factor, confirming the results of previous research. Compared with the English version of the questionnaire, the Cronbach’s alpha coefficient of the Serbian version does not diverge significantly, whereas the factor analysis confirms the classification of the questionnaire into two dimensions. Conclusion Our study has shown that the Serbian version of the SIP questionnaire is a reliable tool for assessing the HRQL of patients with chronic hepatitis B and C before starting treatment

    Critical region of the finite temperature chiral transition

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    We study a Yukawa theory with spontaneous chiral symmetry breaking and with a large number N of fermions near the finite temperature phase transition. Critical properties in such a system can be described by the mean field theory very close to the transition point. We show that the width of the region where non-trivial critical behavior sets in is suppressed by a certain power of 1/N. Our Monte Carlo simulations confirm these analytical results. We discuss implications for the chiral phase transition in QCD.Comment: 18 page

    Advantages and disadvantages of non-starter lactic acid bacteria from traditional fermented foods: potential use as starters or probiotics

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    Research Areas: Food Science & TechnologyTraditional fermented foods are a significant source of starter and/or non-starter lactic acid bacteria (nsLAB). Moreover, these microorganisms are also known for their role as probiotics. The potential of nsLAB is huge; however, there are still challenges to be overcome with respect to characterization and application. In the present review, the most important steps that autochthonous lactic acid bacteria isolated from fermented foods need to overcome, to qualify as novel starter cultures, or as probiotics, in food technology and biotechnology, are considered. These different characterization steps include precise identification, detection of health-promoting properties, and safety evaluation. Each of these features is strain specific and needs to be accurately determined. This review highlights the advantages and disadvantages of nsLAB, isolated from traditional fermented foods, discussing safety aspects and sensory impact.info:eu-repo/semantics/publishedVersio

    Kosterlitz-Thouless Universality in a Fermionic System

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    A new extension of the attractive Hubbard model is constructed to study the critical behavior near a finite temperature superconducting phase transition in two dimensions using the recently developed meron-cluster algorithm. Unlike previous calculations in the attractive Hubbard model which were limited to small lattices, the new algorithm is used to study the critical behavior on lattices as large as 128×128128\times 128. These precise results for the first time show that a fermionic system can undergo a finite temperature phase transition whose critical behavior is well described by the predictions of Kosterlitz and Thouless almost three decades ago. In particular it is confirmed that the spatial winding number susceptibility obeys the well known predictions of finite size scaling for T<TcT<T_c and up to logarithmic corrections the pair susceptibility scales as L2ηL^{2-\eta} at large volumes with 0η0.250\leq\eta\leq 0.25 for 0TTc0\leq T\leq T_c.Comment: Revtex format; 4 pages, 2 figure

    Infrared Behaviour of Systems With Goldstone Bosons

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    We develop various complementary concepts and techniques for handling quantum fluctuations of Goldstone bosons.We emphasise that one of the consequences of the masslessness of Goldstone bosons is that the longitudinal fluctuations also have a diverging susceptibility characterised by an anomalous dimension (d2)(d-2) in space-time dimensions 2<d<42<d<4.In d=4d=4 these fluctuations diverge logarithmically in the infrared region.We show the generality of this phenomenon by providing three arguments based on i). Renormalization group flows, ii). Ward identities, and iii). Schwinger-Dyson equations.We obtain an explicit form for the generating functional of one-particle irreducible vertices of the O(N) (non)--linear σ\sigma--models in the leading 1/N approximation.We show that this incorporates all infrared behaviour correctly both in linear and non-linear σ\sigma-- models. Our techniques provide an alternative to chiral perturbation theory.Some consequences are discussed briefly.Comment: 28 pages,2 Figs, a new section on some universal features of multipion processes has been adde
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