Search results for "instability"
showing 10 items of 724 documents
Role of the antioxidant defence system and telomerase in arsenic-induced genomic instability
2016
Arsenic (AS) is a reactive oxygen species (ROS)-inducer carcinogen, whose mode of action is still unclear. To defend against ROS, cells use enzymatic and non-enzymatic antioxidants, such as superoxide dismutase (SOD) and catalase. Failure of antioxidant systems (AXS) can result in dicentric chromosomes formation as well as telomere associations for the reduced activity of telomerase. In order to clarify the long-term effects of a past AS exposure, we evaluated the efficiency of the AXS and the telomerase activity in the progeny of arsenite-treated cells named ASO (arsenic shake-off) cells, previously obtained from arsenite-treated V79 cells and selected by shake-off. Despite SOD1 expression…
Induction of Chromosome Instability by Activation of Yes-Associated Protein and Forkhead Box M1 in Liver Cancer
2016
Background & Aims Many different types of cancer cells have chromosome instability. The hippo pathway leads to phosphorylation of the transcriptional activator yes-associated protein 1 (YAP1, YAP), which regulates proliferation and has been associated with the development of liver cancer. We investigated the effects of hippo signaling via YAP on chromosome stability and hepatocarcinogenesis in humans and mice. Methods We analyzed transcriptome data from 242 patients with hepatocellular carcinoma (HCC) to search for gene signatures associated with chromosomal instability (CIN); we investigated associations with overall survival time and cancer recurrence using Kaplan–Meier curves. We analyze…
Iwr1 facilitates RNA polymerase II dynamics during transcription elongation.
2017
Iwr1 is an RNA polymerase II (RNPII) interacting protein that directs nuclear import of the enzyme which has been previously assembled in the cytoplasm. Here we present genetic and molecular evidence that links Iwr1 with transcription. Our results indicate that Iwr1 interacts with RNPII during elongation and is involved in the disassembly of the enzyme from chromatin. This function is especially important in resolving problems posed by damage-arrested RNPII, as shown by the sensitivity of iwr1 mutants to genotoxic drugs and the Iwr1's genetic interactions with RNPII degradation pathway mutants. Moreover, absence of Iwr1 causes genome instability that is enhanced by defects in the DNA repair…
Co-chaperone Hsp70/Hsp90-organizing protein (Hop) is required for transposon silencing and Piwi-interacting RNA (piRNA) biogenesis
2017
Piwi-interacting RNAs (piRNAs) are 26–30-nucleotide germ line-specific small non-coding RNAs that have evolutionarily conserved function in mobile genetic element (transposons) silencing and maintenance of genome integrity. Drosophila Hsp70/90-organizing protein homolog (Hop), a co-chaperone, interacts with piRNA-binding protein Piwi and mediates silencing of phenotypic variations. However, it is not known whether Hop has a direct role in piRNA biogenesis and transposon silencing. Here, we show that knockdown of Hop in the germ line nurse cells (GLKD) of Drosophila ovaries leads to activation of transposons. Hop GLKD females can lay eggs at the same rate as wild-type counterparts, but the e…
Genotoxicity and Epigenotoxicity of Carbazole-Derived Molecules on MCF-7 Breast Cancer Cells
2021
The carbazole compounds PK9320 (1-(9-ethyl-7-(furan-2-yl)-9H-carbazol-3-yl)-N-methylmethanamine) and PK9323 (1-(9-ethyl-7-(thiazol-4-yl)-9H-carbazol-3-yl)-N-methylmethanamine), second-generation analogues of PK083 (1-(9-ethyl-9H-carbazol-3-yl)-N-methylmethanamine), restore p53 signaling in Y220C p53-mutated cancer cells by binding to a mutation-induced surface crevice and acting as molecular chaperones. In the present paper, these three molecules have been tested for mutant p53-independent genotoxic and epigenomic effects on wild-type p53 MCF-7 breast adenocarcinoma cells, employing a combination of Western blot for phospho-γH2AX histone, Comet assay and methylation-sensitive arbitrarily pr…
The role of internal corporate governance mechanisms on default risk: A systematic review for different institutional settings
2020
Recent financial downturns, characterized by the significant failures of firms, have revealed the need to control credit risk. Latest literature has shown that weak corporate governance structures are related to high levels of default risk, leading to financial instability. In this context, we aim to summarize the literature that focuses on the role that internal corporate governance plays in the credit risk of firms, specifically considering three corporate governance components: ownership structure, board structure and financial stakeholders’ rights and relations. Additionally, we analyse whether the effectiveness of the internal mechanisms depends on particular key factors, especially th…
Parenting and adolescent adjustment: The mediational role of family self-esteem
2021
The present study analyzes the relationship between parental socialization practices, acceptance/involvement, and strictness/ imposition, and different indicators of adolescent adjustment, taking into account the role of family self-esteem. A sample of 848 Spanish adolescents (54.70% females) ranging in age from 14 to 18 years old (M = 16.11, SD = 1.10) participated in the study. A series of structural equations models (SEMs) were tested to examine the mediational role of family self-esteem in the relationship between parenting practices and the outcome variables that capture adolescent adjustment: emotional instability, antisocial behavior, and academic achievement. The influence of parent…
Condicionantes de los procesos de flexibilización y precarización en el contexto de la globalización : un estudio comparativo del sector de las nueva…
2014
El objetivo principal de la tesis es realizar un análisis sobre España (Unión Europea) y Brasil (Latinoamérica), respecto a los condicionantes de los procesos de flexibilización y precarización en el contexto de la globalización y efectuar un estudio comparativo profundizando en el sector de las nuevas tecnologías de la información y de la comunicación en España y Brasil y su inserción en tres sectores dinámicos: banca, informática y telecomunicaciones en las dos economías en estudio. La hipótesis central de la investigación es que la utilización de las tecnologías de la información y de la comunicación genera tanto flexibilidad como precariedad laboral en el ámbito de las empresas, pero es…
Roadmap on optical rogue waves and extreme events
2016
Nail Akhmediev et al. ; 38 págs.; 28 figs.
Vector FWM in optical fibers: tuning techniques and applications
2022
Recientemente, el efecto no lineal de mezcla de cuatro ondas (FWM) en fibras ópticas ha atraído un gran interés para el desarrollo de nuevas fuentes de luz de fibra óptica debido a la emisión de luz múltiple producida por este efecto no lineal. En los últimos años, estas fuentes de luz basadas en FWM han demostrado una gran utilidad en áreas como la óptica cuántica y la microscopía avanzada basada en efecto Raman. Además, según el estado de polarización de la luz de bombeo responsable del efecto FWM y la birrefringencia de la fibra, la luz producida por FWM puede presentar diferentes propiedades de polarización dada la naturaleza vectorial de FWM. Esto posibilita el diseño y desarrollo de f…