Search results for "TRIP"
showing 10 items of 2134 documents
Neuronal Bioenergetics and Acute Mitochondrial Dysfunction: A Clue to Understanding the Central Nervous System Side Effects of Efavirenz
2014
Background. Neurological pathogenesis is associated with mitochondrial dysfunction and differences in neuronal/glial handling of oxygen and glucose. The main side effects attributed to efavirenz involve the CNS, but the underlying mechanisms are unclear. Methods. Human cell lines and rat primary cultures of neurons and astrocytes were treated with clinically relevant efavirenz concentration. Results. Efavirenz alters mitochondrial respiration, enhances reactive oxygen species generation, undermines mitochondrial membrane potential, and reduces adenosine triphosphate (ATP) levels in a concentration-dependent fashion in both neurons and glial cells. However, it activates adenosine monophospha…
Inhibition of Mitochondrial Function by Efavirenz Increases Lipid Content in Hepatic Cells
2010
Efavirenz (EFV) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) widely used in human immunodeficiency virus (HIV) infection therapy. It has been associated with hepatotoxic effects and alterations in lipid and body fat composition. Given the importance of the liver in lipid regulation, we have evaluated the effects of clinically used concentrations of EFV on the mitochondria and lipid metabolism of human hepatic cells in vitro. Mitochondrial function was rapidly undermined by EFV to an extent that varied with the concentration employed; in particular, respiration and intracellular adenosine triphosphate (ATP) levels were reduced whereas reactive oxygen species (ROS) production i…
Inhibition of Efavirenz Metabolism by Sertraline and Nortriptyline and Their Effect on Efavirenz Plasma Concentrations.
2015
ABSTRACT Between 22 and 45% of HIV-positive subjects are likely to report symptoms of depression. Considering this background, a potential pharmacokinetic interaction between the nonnucleoside reverse transcriptase inhibitor efavirenz (EFV) and two antidepressants, sertraline (SRT) and nortriptyline (NT), was studied. Rats were administered EFV alone or together with the antidepressants, and changes in the plasma levels and pharmacokinetic parameters of EFV were analyzed. Additional in vitro experiments with rat and human hepatic microsomes were carried out to evaluate the inhibitory effect of SRT and NT on EFV metabolism by determining the formation rate of the major EFV metabolite (8-OH-E…
Nuclear Translocation of Mismatch Repair Proteins MSH2 and MSH6 as a Response of Cells to Alkylating Agents
2000
Mammalian mismatch repair has been implicated in mismatch correction, the prevention of mutagenesis and cancer, and the induction of genotoxicity and apoptosis. Here, we show that treatment of cells specifically with agents inducing O(6)-methylguanine in DNA, such as N-methyl-N'-nitro-N-nitrosoguanidine and N-methyl-N-nitrosourea, elevates the level of MSH2 and MSH6 and increases GT mismatch binding activity in the nucleus. This inducible response occurs immediately after alkylation, is long-lasting and dose-dependent, and results from translocation of the preformed MutSalpha complex (composed of MSH2 and MSH6) from the cytoplasm into the nucleus. It is not caused by an increase in MSH2 gen…
Regulation of ribonucleotide reductase in response to iron deficiency
2011
Ribonucleotide reductase (RNR) is an essential enzyme required for DNA synthesis and repair. Although iron is necessary for class Ia RNR activity, little is known about the mechanisms that control RNR in response to iron deficiency. In this work, we demonstrate that yeast cells control RNR function during iron deficiency by redistributing the Rnr2–Rnr4 small subunit from the nucleus to the cytoplasm. Our data support a Mec1/Rad53-independent mechanism in which the iron-regulated Cth1/Cth2 mRNA-binding proteins specifically interact with the WTM1 mRNA in response to iron scarcity, and promote its degradation. The resulting decrease in the nuclear-anchoring Wtm1 protein levels leads to the re…
Differential salinity-induced variations in the activity of H+-pumps and Na+/H+ antiporters that are involved in cytoplasm ion homeostasis as a funct…
2011
The characterisation of cellular responses to salinity in staple crops is necessary for the reliable identification of physiological markers of salinity tolerance. Under saline conditions, variations in proton gradients that are generated by membrane-bound H⁺ pumps are crucial for maintaining cytoplasm homeostasis. We examined short (15 h) and longer term effects (4 days) of NaCl stress on the H⁺ pumping activities that are associated with the plasma membrane (P-ATPase) and the tonoplast (V-ATPase and V-PPase) in rice (Oryza sativa L.) callus lines that displayed different levels of NaCl tolerance and were established from two japonica rice cultivars. The applied stress conditions were base…
Impaired Transporter Associated with Antigen Processing (TAP) Function Attributable to a Single Amino Acid Alteration in the Peptide TAP Subunit TAP1
2003
Abstract The heterodimeric peptide transporter TAP belongs to the ABC transporter family. Sequence comparisons with the P-glycoprotein and cystic fibrosis transmembrane conductance regulator and the functional properties of selective amino acids in these ABC transporters postulated that the glutamic acid at position 263 and the phenylalanine at position 265 of the TAP1 subunit could affect peptide transporter function. To define the role of both amino acids, TAP1 mutants containing a deletion or a substitution to alanine at position 263 or 265 were generated and stably expressed in murine and human TAP1−/− cells. The different TAP1 mutants were characterized in terms of expression and funct…
El aprovechamiento del cómic como herramienta didáctica desde el enfoque comunicativo
2015
Resumen: El cómic es un recurso que, en muchos casos, se utiliza de modo anecdótico en el aula y con una función puramente de entretenimiento, sin dar muchas veces la importancia que se merece a lo que muchos consideran el noveno arte. Esta experiencia práctica pretende mostrar la idoneidad y la versatilidad de este medio narrativo en el aula de español como lengua extranjera. Tras un breve acercamiento teórico al uso del cómic en el aula de E/LE, se presentan los resultados de un análisis previo sobre la presencia de cómics en los manuales de E/LE. Las diferentes aplicaciones didácticas que se presentan, dirigidas a diferentes niveles que oscilan desde el nivel B1 hasta el C2, suplen las c…
Impact des allocations en ressources sur l'efficacité des écoles primaires en Côte d'Ivoire
2011
The quality of primary education in Côte d'Ivoire has deteriorated sharply over the past three decades. This situation is the result of an approximate management of the education system, which is characterized by a lack of educational support, a misallocation of resources, a congestion of classrooms (42 students for a teacher in primary school) and a lack of skilled and well trained teachers. In addition, the military-political conflict in September 2002 did not allow to improve this situation; on the contrary, it has further deteriorated the situation. Thus, the aim of this thesis is first to analyze the influence of resource endowments on the effectiveness of primary schools in Cote d'Ivo…
Structure and Deformations of Pd−Ni Core−Shell Nanoparticles
2005
International audience; Homogeneous collections of Pd−Ni core−shell nanoparticles have been prepared by decomposition of metal−organic compounds and studied by several electron microscopy techniques: transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM), energy-filtered microscopy (EFTEM), and by X-ray photoelectron spectroscopy (XPS). The physical and chemical properties of the Pd shell are supposed to depend on its electronic properties, which are influenced by the presence of the Ni core and by the deformation in the Pd lattice. Here, the interfacial structure of Pd/Ni and the lattice deformations in t…