198 research outputs found
Resveratrol: A Focus on Several Neurodegenerative Diseases
Molecules of the plant world are proving their effectiveness in countering, slowing down, and regressing many diseases. The resveratrol for its intrinsic properties related to its stilbene structure has been proven to be a universal panacea, especially for a wide range of neurodegenerative diseases. This paper evaluates (in vivo and in vitro) the various molecular targets of this peculiar polyphenol and its ability to effectively counter several neurodegenerative disorders such as Parkinson’s, Alzheimer’s, and Huntington’s diseases and amyotrophic lateral sclerosis. What emerges is that, in the deep heterogeneity of the pathologies evaluated, resveratrol through a convergence on the protein targets is able to give therapeutic responses in neuronal cells deeply diversified not only in morphological structure but especially in their function performed in the anatomical district to which they belong
Duplication of the dystroglycan gene in most branches of teleost fish
<p>Abstract</p> <p>Background</p> <p>The dystroglycan (DG) complex is a major non-integrin cell adhesion system whose multiple biological roles involve, among others, skeletal muscle stability, embryonic development and synapse maturation. DG is composed of two subunits: α-DG, extracellular and highly glycosylated, and the transmembrane β-DG, linking the cytoskeleton to the surrounding basement membrane in a wide variety of tissues. A single copy of the DG gene (<it>DAG1</it>) has been identified so far in humans and other mammals, encoding for a precursor protein which is post-translationally cleaved to liberate the two DG subunits. Similarly, <it>D. rerio </it>(zebrafish) seems to have a single copy of <it>DAG1</it>, whose removal was shown to cause a severe dystrophic phenotype in adult animals, although it is known that during evolution, due to a whole genome duplication (WGD) event, many teleost fish acquired multiple copies of several genes (paralogues).</p> <p>Results</p> <p>Data mining of pufferfish (<it>T. nigroviridis </it>and <it>T. rubripes</it>) and other teleost fish (<it>O. latipes </it>and <it>G. aculeatus</it>) available nucleotide sequences revealed the presence of two functional paralogous DG sequences. RT-PCR analysis proved that both the DG sequences are transcribed in <it>T. nigroviridis</it>. One of the two DG sequences harbours an additional mini-intronic sequence, 137 bp long, interrupting the uncomplicated exon-intron-exon pattern displayed by <it>DAG1 </it>in mammals and <it>D. rerio</it>. A similar scenario emerged also in <it>D. labrax </it>(sea bass), from whose genome we have cloned and sequenced a new DG sequence that also harbours a shorter additional intronic sequence of 116 bp. Western blot analysis confirmed the presence of DG protein products in all the species analysed including two teleost Antarctic species (<it>T. bernacchii </it>and <it>C. hamatus</it>).</p> <p>Conclusion</p> <p>Our evolutionary analysis has shown that the whole-genome duplication event in the Class Actinopterygii (ray-finned fish) involved also <it>DAG1</it>. We unravelled new important molecular genetic details about fish orthologous DGs, which might help to increase the current knowledge on DG expression, maturation and targeting and on its physiopathological role in higher organisms.</p
Band-3 protein function in human erythrocytes: effect of oxygenation–deoxygenation
AbstractSulfate transport by band-3 protein in adult human erythrocytes was shown to be modulated by oxygen pressure. In particular, a higher transport activity was measured under high oxygen pressure than at low one (0.0242±0.0073 vs. 0.0074±0.0010 min−1). Other factors, such as magnesium ions and orthovanadate, which can indirectly affect the binding properties of the cytoplasmic domain of band 3 (cdb3), influence significantly the anion exchanger activity. No effect of oxygen pressure on sulfate transport was found in chicken erythrocytes, which may be related to their lacking the cdb3 binding site. These findings are fully consistent with a molecular mechanism where the oxygen-linked transition of hemoglobin (T→R) could play a key role in the regulation of anion exchanger activity
Measurement of the Lifetime Difference Between B_s Mass Eigenstates
We present measurements of the lifetimes and polarization amplitudes for B_s
--> J/psi phi and B_d --> J/psi K*0 decays. Lifetimes of the heavy (H) and
light (L) mass eigenstates in the B_s system are separately measured for the
first time by determining the relative contributions of amplitudes with
definite CP as a function of the decay time. Using 203 +/- 15 B_s decays, we
obtain tau_L = (1.05 +{0.16}/-{0.13} +/- 0.02) ps and tau_H = (2.07
+{0.58}/-{0.46} +/- 0.03) ps. Expressed in terms of the difference DeltaGamma_s
and average Gamma_s, of the decay rates of the two eigenstates, the results are
DeltaGamma_s/Gamma_s = (65 +{25}/-{33} +/- 1)%, and DeltaGamma_s = (0.47
+{0.19}/-{0.24} +/- 0.01) inverse ps.Comment: 8 pages, 3 figures, 2 tables; as published in Physical Review Letters
on 16 March 2005; revisions are for length and typesetting only, no changes
in results or conclusion
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is . The combined inclusive and differential asymmetries are consistent with recent standard model predictions
A New Non-Equilibrium Thermodynamic Fractional Visco-Inelastic Model to Predict Experimentally Inaccessible Processes and Investigate Pathophysiological Cellular Structures
After remarking on non-equilibrium thermodynamics with internal variables, this paper highlights the importance of these variables to the study of biological systems. Internal variables can provide a more detailed description of biological processes that occur inside cells, tissues and organs. In order to introduce a fractional model on a visco-inelastic medium based on Kluitenberg’s non-equilibrium thermodynamics, the origin of the complex dynamic modulus is shown by means of linear response theory. This research recalls our previous work to develop an ultrasound wave technique that allows us to investigate biological systems, and introduces the fractional visco-inelastic model and relative generalized relaxation time, to show that it is possible to obtain the Cole–Cole model in a particular case
A New Non-Equilibrium Thermodynamic Fractional Visco-Inelastic Model to Predict Experimentally Inaccessible Processes and Investigate Pathophysiological Cellular Structures
After remarking on non-equilibrium thermodynamics with internal variables, this paper highlights the importance of these variables to the study of biological systems. Internal variables can provide a more detailed description of biological processes that occur inside cells, tissues and organs. In order to introduce a fractional model on a visco-inelastic medium based on Kluitenberg’s non-equilibrium thermodynamics, the origin of the complex dynamic modulus is shown by means of linear response theory. This research recalls our previous work to develop an ultrasound wave technique that allows us to investigate biological systems, and introduces the fractional visco-inelastic model and relative generalized relaxation time, to show that it is possible to obtain the Cole–Cole model in a particular case
Thermodynamics Characterization of Lung Carcinoma, Entropic Study and Metabolic Correlations
In recent years, the use of dielectric spectroscopy as an investigation technique to determine the chemical–physical characteristics of biological materials has had a great increase. This study used the non-equilibrium thermodynamics with internal variables theory to test the potential pathological features of lung cancer. After a brief exploration of the dielectric polarization concept highlighting some aspects that were used, some thermodynamic functions were obtained as functions of the frequency, both for lung tumor cells and physiological ones. Variations in the intensity of values but not in the trend of the curves were observed and this was attributed to the perturbing field. The trend of this field explains the behavior of phenomena described by other functions, as related to the frequencies of the perturbing field. Compared to the physiological ones, the cancer cells appeared to be “more predisposed” to conserve their state as characterized by minor entropy production, probably because this helped cells to obtain the required adenosine triphosphate (ATP) from the minimum amount of nutrients
Expanding the Repertoire of Dielectric Fractional Models: A Comprehensive Development and Functional Applications to Predict Metabolic Alterations in Experimentally-Inaccessible Cells or Tissues
In this paper, we present the theoretical approach developed by us in the network of dielectric fractional theories. In particular, we mention the general aspects of the non-equilibrium thermodynamics, and after an introduction to the interaction between biological tissues and electrical fields, we highlight the role of phenomenological and state equations; therefore, we recall a general formulation on linear response theory. In Section 6, we introduce the classical fractional model. All of this is essential to show the role and the importance of fractional models in the context of thermodynamic dielectric investigations (of living or inert matter), giving a complete vision of the fractional approach. In Section 7 and Section 8, we introduce our new fractional model derived from non-equilibrium thermodynamic considerations
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