Search results for "mitos"
showing 10 items of 190 documents
Proyección y reivindicación de los poetas yahilíes en la poesía árabe contemporánea.
2001
Veglison Elias de Molins, Josefina - Josefina.Veglison@uv.es Este articulo analiza las referencias a poetas de la Yahiliyya presentes en la poesía árabe contemporánea en calidad de mitos y arquetipos. Cabe destacar el hecho de que éstos sean beduinos pertenecientes a la categoría de autores de mu'allaqa o al grupo de poetas bandoleros (sa'álik). El autor contemporáneo rescata sus figuras porque interpreta como signo de modernidad su talante innovador y su rebeldía contra la norma, tanto en lo formal como en los contenidos. Esta reivindicación se lleva a cabo, en los contenidos, mediante la evocación de sus nombres en poemas o títulos de diwanes, la inclusión de sus versos o la réplica a sus…
Survivin’s Dual Role: An Export’s View
2007
Survivin is proposed to function as a mitotic regulator and an apoptosis inhibitor during development and pathogenesis. As such, survivin has aroused keen interest in disparate areas of basic and translational research. Survivin acts as a subunit of the chromosomal passenger complex (CPC), composed of the mitotic kinase Aurora-B, Borealin and INCENP, and is essential for proper chromosome segregation and cytokinesis. Our recent findings indicate that the nuclear export receptor Crm1 is critically involved in tethering the CPC to the centromere by interacting with a leucine-rich nuclear export signal (NES), evolutionary conserved in all mammalian survivin proteins. In addition, the survivin/…
MAD2 depletion triggers premature cellular senescence in human primary fibroblasts by activating a P53 pathway preventing aneuploid cells propagation.
2012
The spindle assembly checkpoint (SAC) is a cellular surveillance mechanism that ensures faithful chromosome segregation during mitosis and its failure can result in aneuploidy. Previously, it was suggested that reduction of the MAD2 gene, encoding a major component of the SAC, induced aneuploidy in human tumor cells. However, tumor cell lines contain multiple mutations that might affect or exacerbate the cellular response to Mad2 depletion. Thus, the scenario resulting by Mad2 depletion in primary human cells could be different and more complex that the one depicted so far. We used primary human fibroblasts (IMR90) and epithelial breast cells (MCF10A) to gain further insight on the effects …
Study of Proliferation and Apoptosis in Neuroblastoma. Their Relation with Other Prognostic Factors
2002
Abstract Background Our objective was to study the proliferation and apoptotic process in 111 cases of neuroblastoma (NB) and to seek their relationship with other prognostic factors and survival. Methods Immunohistochemistry following ABC peroxidase was carried out for PCNA, Ki-67, bcl-2, and p53 proteins. Apoptosis analysis was performed with in situ detection of chromosomal breakdown. Molecular detection of DNA ladders by electrophoresis and amplification of MYCN was studied with PCR and Southern blot. Statistical study was performed with Pearson χ 2 and Kruskal-Wallis tests and Cox regression. Results Our results indicate that proliferative factors PCNA and Ki-67 were correlated to each…
Growth and macromolecular content of the dimorphic fungus Aureobasidium pullulans and the effect of hydroxyurea and other inhibitors
1988
The growth kinetics and the macromolecular content of the yeast and ethanol-induced hyphal forms of Aureobasidium pullulans were studied. During the morphological transition from yeasts to hyphae, both the protein and RNA content decreased significantly, the mycelial form containing only 76% of the amount of protein in the yeasts, and 38% of the RNA. The DNA was the only component tested whose level increased during the transition. Among several compounds inhibiting macromolecular synthesis, only hydroxyurea showed a remarkable effect on the morphology of A. pullulans, inducing the mycelial morphology. The macromolecular composition of hydroxyurea-treated cultures changed with time in a way…
The role of Aurora-A inhibitors in cancer therapy
2007
Recently, new chemotherapy agents which target the non-structural components of mitosis have been developed. An important protein involved in several mitotic phases is the Aurora-A protein. By means of the phosphorylation of different substrates, Aurora-A regulates the correct development of the various phases of mitosis. The kinase activity of this protein makes Aurora-A an excellent candidate as an oncogene. The first data of Aurora-A involvement in cancer regarded the identification of Aurora-A overexpression in primary breast and colon tumour samples. With regard to the predictive role of Aurora-A, it has been shown that its overexpression disrupts the spindle checkpoint activated by pa…
Two new conidial lichenicolous fungi from Spain indicate the distinction ofLichenodiplisandMinutoexcipula
2009
AbstractTwo new conidial lichenicolous fungi are described from Spain:Lichenodiplis crespoaeonCyphelium notarisiiandMinutoexcipula tephromelaeonTephromela atra.Lichenodiplis crespoaediffers from all the described species of the genus in the narrower and shorter conidia, and the hostCyphelium notarisii.Minutoexcipula tephromelaeis characterized by subglobose, conidiogenous cells occasionally bearing 1–2 long proliferating extensions, short conidia and by the hostTephromela atra.
Synthesis and evaluation of microtubule assembly inhibition and cytotoxicity of prenylated derivatives of cyclo-l-Trp-l-Pro
2000
The synthesis of three isoprenylated derivatives of cyclo-L-Trp-L-Pro is described. These substances have been evaluated for cytotoxic activity in rat normal fibroblast 3Y1 cells and have also been evaluated in vitro for the inhibition of microtubule assembly.
The Cell Cycle-Specific Growth-Inhibitory Factor Produced by Actinobacillus actinomycetemcomitans Is a Cytolethal Distending Toxin
1998
ABSTRACT Actinobacillus actinomycetemcomitans has been shown to produce a soluble cytotoxic factor(s) distinct from leukotoxin. We have identified in A. actinomycetemcomitans Y4 a cluster of genes encoding a cytolethal distending toxin (CDT). This new member of the CDT family is similar to the CDT produced by Haemophilus ducreyi . The CDT from A. actinomycetemcomitans was produced in Escherichia coli and was able to induce cell distension, growth arrest in G 2 /M phase, nucleus swelling, and chromatin fragmentation in HeLa cells. The three proteins, CDTA, -B and -C, encoded by the cdt locus were all required for toxin activity. Antiserum raised against recombinant CDTC completely inhibited …
Relationship between ethanol tolerance, lipid composition and plasma membrane fluidity inSaccharomyces cerevisiaeandKloeckera apiculata
1994
The lipid composition of a strain of each of two yeasts, Saccharomyces csrevisiae and Kloeckera apiculata, with different ethanol tolerances, was determined for cells grown with or without added ethanol. An increase in the proportion of ergosterol, unsaturated fatty acid levels and the maintenance of phospholipid biosynthesis seemed to be responsible for ethanol tolerance. The association of ethanol tolerance of yeast cells with plasma membrane fluidity, measured by fluorescence anisotropy, is discussed. We propose that an increase in plasma membrane fluidity may be correlated with a decrease in the sterol: phospholipid and sterol: protein ratios and an increase in unsaturation index.