274 research outputs found
Introduzione
EnIn this note the notion of projctive pseudoconnexion is introduced and some geometrical properties are studied
Effects of n-Octyl-β-D-Glucopyranoside on Human and Rat Erythrocyte Membrane Stability against Hemolysis
The practical importance for the pharmaceutical and cosmetics industries of the interactions between biological membranes and surfactant molecules has led to intensive research within this area. The interactions of non-ionic surfactant n-octyl-β-D-glucopyranoside (OG) with the human and rat erythrocyte membranes were studied. The in vitro hemolytic and antihemolytic activities were determined by employing a method in which both erythrocytes were added to the hypotonic medium containing OG at different concentrations, and the amount of haemoglobin released was determined. n-octyl-β-D-glucopyranoside was found to have a biphasic effect on both types of erythrocyte membrane. We also investigated the interactions of OG with the erythrocyte membrane in isotonic medium; the dose-dependent curves show similar behaviour in both human and rat erythrocytes. Our results showed that OG has greater antihemolytic potency on rat than on human erythrocytes; furthermore, rat erythrocytes were more sensitive than human erythrocytes to hypotonic shock. How the different lipoprotein structure of these erythrocytes determines a difference in antihemolytic activity is discussed
Characterization of proton irradiated 3D-DDTC pixel sensor prototypes fabricated at FBK
In this paper we discuss results relevant to 3D Double-Side Double Type
Column (3D-DDTC) pixel sensors fabricated at FBK (Trento, Italy) and oriented
to the ATLAS upgrade. Some assemblies of these sensors featuring different
columnar electrode configurations (2, 3, or 4 columns per pixel) and coupled to
the ATLAS FEI3 read-out chip were irradiated up to large proton fluences and
tested in laboratory with radioactive sources. In spite of the non optimized
columnar electrode overlap, sensors exhibit reasonably good charge collection
properties up to an irradiation fluence of 2 x 10**15 neq/cm2, while requiring
bias voltages in the order of 100 V. Sensor operation is further investigated
by means of TCAD simulations which can effectively explain the basic mechanisms
responsible for charge loss after irradiation.Comment: Preprint submitted to Nuclear Instruments and Methods A, 11 pages, 13
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Respiratory chain complex I, a main regulatory target of the cAMP/PKA pathway is defective in different human diseases.
In mammals, complex I (NADH-ubiquinone oxidoreductase) of the mitochondrial respiratory chain has 31 supernumerary subunits in addition to the 14 conserved from prokaryotes to humans. Multiplicity of structural protein components, as well as of biogenesis factors, makes complex I a sensible pace-maker of mitochondrial respiration. The work reviewed here shows that the cAMP/PKA pathway regulates the biogenesis, assembly and catalytic activity of complex I and mitochondrial oxygen superoxide production. The structural, functional and regulatory complexity of complex I, renders it particularly vulnerable to genetic and sporadic pathological factors. Complex I dysfunction has, indeed, been found, to be associated with several human diseases. Knowledge of the pathogenetic mechanisms of these diseases can help to develop new therapeutic strategies. (C) 2011 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved
Respiratory chain complex I, a main regulatory target of the cAMP/PKA pathway is defective in different human diseases
In mammals, complex I (NADH-ubiquinone oxidoreductase) of the mitochondrial respiratory chain has 31 supernumerary subunits in addition to the 14 conserved from prokaryotes to humans. Multiplicity of structural protein components, as well as of biogenesis factors, makes complex I a sensible pace-maker of mitochondrial respiration. The work reviewed here shows that the cAMP/PKA pathway regulates the biogenesis, assembly and catalytic activity of complex I and mitochondrial oxygen superoxide production. The structural, functional and regulatory complexity of complex I, renders it particularly vulnerable to genetic and sporadic pathological factors. Complex I dysfunction has, indeed, been found, to be associated with several human diseases. Knowledge of the pathogenetic mechanisms of these diseases can help to develop new therapeutic strategies. (C) 2011 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved
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