Search results for "Repo"
showing 10 items of 2753 documents
Transcriptional Regulation of Human CYP3A4 Basal Expression by CCAAT Enhancer-Binding Protein α and Hepatocyte Nuclear Factor-3γ
2003
Cytochrome P450 3A4 (CYP3A4) is involved in the metabolism of more than 50% of currently used therapeutic drugs, yet the mechanisms that control CYP3A4 basal expression in liver are poorly understood. Several putative binding sites for CCAAT/enhancer-binding protein (C/EBP) and hepatic nuclear factor 3 (HNF-3) were found by computer analysis in CYP3A4 promoter. The use of reporter gene assays, electrophoretic mobility shift assays, and site-directed mutagenesis revealed that one proximal and two distal C/EBP alpha binding sites are essential sites for the trans-activation of CYP3A4 promoter. No trans-activation was found in similar reporter gene experiments with a HNF-3 gamma expression vec…
Physiological activation of the IgH 3' enhancer in B lineage cells is not blocked by Pax-5.
1996
The mouse 3' enhancer contains a high-affinity binding site for the paired box protein Pax-5. Here, we demonstrate by genomic footprinting that the rat 3' enhancer contains a low-affinity binding site for Pax-5, which is occupied in activated splenic B cells. Thus, binding of Pax-5 to the IgH 3' enhancer appears to be evolutionarily conserved in rodents. Analysis of Pax-5 expression in primary B cells demonstrates that Pax-5 remains expressed after 4 days of lipopolysaccharide (LPS) induction, but is down-regulated in 5-day stimulated cells. Similarly, the expression of Pax-5 is down-regulated in vivo in activated large splenocytes, in contrast to small resting cells. Multimerization of the…
The yopJ locus is required for Yersinia-mediated inhibition of NF-kappaB activation and cytokine expression: YopJ contains a eukaryotic SH2-like doma…
1998
Upon exposure to bacteria, eukaryotic cells activate signalling pathways that result in the increased expression of several defence-related genes. Here, we report that the yopJ locus of the enteropathogen Yersinia pseudotuberculosis encodes a protein that inhibits the activation of NF-kappaB transcription factors by a mechanism(s), which prevents the phosphorylation and subsequent degradation of the inhibitor protein IkappaB. Consequently, eukaryotic cells infected with YopJ-expressing Yersinia become impaired in NF-kappaB-dependent cytokine expression. In addition, the blockage of inducible cytokine production coincides with yopJ-dependent induction of apoptosis. Interestingly, the YopJ pr…
Ionizing radiation-induced E-selectin gene expression and tumor cell adhesion is inhibited by lovastatin and all-trans retinoic acid
2004
E-selectin mediated tumor cell adhesion plays an important role in metastasis. Here we show that ionizing radiation (IR) induces E-selectin gene and protein expression in human endothelial cells at therapeutically relevant dose level. E-selectin expression is accompanied by an increase in the adhesion of human colon carcinoma cells to primary human umbilical vein endothelial cells (HUVEC). The HMG-CoA reductase inhibitor lovastatin impairs IR-stimulated E-selectin expression as analyzed at the level of the protein, mRNA and promoter. Inactivation of Rho GTPases either by use of Clostridium difficile toxin A or by co-expression of dominant-negative Rho blocked IR-induced E-selectin gene indu…
The Arabidopsis Copper Transporter COPT1 Functions in Root Elongation and Pollen Development
2004
Copper plays a dual role in aerobic organisms, as both an essential and a potentially toxic element. To ensure copper availability while avoiding its toxic effects, organisms have developed complex homeostatic networks to control copper uptake, distribution, and utilization. In eukaryotes, including yeasts and mammals, high affinity copper uptake is mediated by the Ctr family of copper transporters. This work is the first report on the physiological function of copper transport in Arabidopsis thaliana. We have studied the expression pattern of COPT1 in transgenic plants expressing a reporter gene under the control of the COPT1 promoter. The reporter gene is highly expressed in embryos, tric…
Expression of a reporter gene is reduced by a ribozyme in transgenic plants
1994
A chimeric gene encoding a ribozyme under the control of the cauliflower mosaic virus (CaMV) 35S promoter was introduced into transgenic tobacco plants. In vivo activity of this ribozyme, which was designed to cleave npt mRNA, was previously demonstrated by transient expression assays in plant protoplasts. The ribozyme gene was transferred into transgenic tobacco plants expressing an rbcS-npt chimeric gene as an indicator. Five double transformants out of sixteen exhibited a reduction in the amount of active NPT enzyme. To measure the amount of ribozyme produced, in the absence of its target, the ribozyme and target genes were separated by genetic segregation. The steady-state concentration…
La transgresión de la realidad en el reportaje televisivo : El tratamiento del caso “El Cabanyal”
2009
En esta comunicación se parte, como supuesto previo, de que la lógica económica que define la estructura y dinámica del sistema de la comunicación global y local determina el tratamiento y la construcción de la realidad social en el conjunto de discursos que se construyen en los diferentes medios de comunicación. En este caso, el objeto de estudio es, precisamente, constatar que, como efecto relevante de la lógica dominante citada, la construcción discursiva audiovisual del programa de Cuatro Callejeros se lleva a cabo trasgrediendo la realidad social que pretende trasmitir, “la cotidianidad del barrio del Cabanyal en Valencia” y convirtiéndola en espectáculo persuasivo para consumidores en…
Intorno allo Stato da Mar: il viaggio del bailo Giorgio Giustinian da Costantinopoli a Venezia (1627)
2023
Presentation and analysis of the Relazione (Report) on the return voyage of Giorgio Giustinian, Bailo of Constantinople (1627), of particular interest due to the exceptional nature of the itinerary followed, which progressed into Macedonia and Serbia as far as Sofia and Belgrade and then turned towards Sarajevo, Mostar and reached Spalato. The document allows us to add an important element to the voyage reports between Venice and Constantinople, at the moment when the difficult relations between the Most Serene Republic and the Ottoman Empire seemed having found a new balance at the expense of the Republic of Ragusa. The unpublished Relazione is provided in the Appendix.
Identification of the ectosymbiotic bacteria of Mixotricha paradoxa involved in movement symbiosis
2003
Mixotricha paradoxa, a trichomonad from the hindgut of the Australian termite Mastotermes darwiniensis Froggatt, is a rare example of a movement symbiosis between eukaryotic and prokaryotic microorganisms. The surface of Mixotricha paradoxa is covered with spirochaetes and a rod-shaped bacterium. The four flagella at the anterior end seem only to alter the direction of movement, while the ectosymbiotic spirochaetes propel the flagellate cells. Based on a 16S rDNA sequence analysis after a semi-specific PCR, and subsequent fluorescence in situ hybridization applying helper oligonucleotides and a denaturing step of the 16S rRNA, three different spirochaete clones could be clearly identified o…
Fluorescenzserologischer Nachweis eines in Syphilitikerseren vorkommenden Antik�rpers gegen ein hitzestabiles Antigen der Reiter-Treponemen
1967
An insgesamt 88 Syphilitikerseren wurde der FTA-Test mit erhitzten Reiter-Treponemen durchgefuhrt. 71 mal reagierte die Serumverdunnung von 1∶100, in 53 Fallen eine solche von 1∶500 positiv. Von 53 Kontrollseren waren nur 2 bei der Verdunnung von 1∶100 positiv. Hieraus wird auf das Vorkommen eines hitzestabilen gemeinsamen Gruppen-Antigens in Reiter-Treponemen und T. pallidum geschlossen. Die Zugehorigkeit dieses Antigens zu den Lipopolysacchariden wird diskutiert. Menschliche Antikorper gegen dieses Antigen sind vorerst nur fluorescenzserologisch nachzuweisen.