Search results for "mitos"
showing 10 items of 190 documents
Endoreduplication induced in cultured Chinese hamster cells by different anti-topoisomerase II chemicals
2005
With the ultimate purpose of testing the hypothesis that, as shown in yeast mutants, any malfunction of DNA topoisomerase II might result in aberrant mitosis due to defective chromosome segregation, we have chosen three chemicals of different nature, recently reported to catalytically inhibit the enzyme. The endpoint selected to assess any negative effect on the ability of topoisomerase II to properly carry out decatenation of fully replicated chromosomes in the G2/M phase of the cell cycle was the presence of metaphases showing diplochromosomes as a result of endoreduplication, i.e. two successive rounds of DNA replication without intervening mitosis. The anti-topoisomerase drugs selected …
Organometallic complexes with biological molecues, part 3.in vivo cytotoxicity of diorganotin (IV) chloro and triorganotin (IV) chloro derivatives of…
1994
In order to obtain a continuous source of mitotic metaphases, gill tissue of Aphaius fasciatus (Pisces, Cyprinodontiformes) has been successfully employed. Results gathered after exposure of fish to R2SnClpenG, R3SnClpenGNa, to the parents R2SnCl2, R3SnCl and to penGNa (penGNa = penicillinGNa; R = methyl, butyl and phenyl) suggest that both the parent organotin (IV) chloride and organotin (IV) chloropenG derivatives are toxic while penGNa exerts no significant toxic activity. Essentially, all of the chromosome abnormalities are classifiable as irregularly staining of chromosomes, breakages, side-arm bridges or pseudochiasmata.
Genetic and Molecular Characterization of The Human Osteosarcoma 3AB-OS Cancer Stem Cell Line: A Possible Model For Studying Osteosarcoma Origin and …
2013
Finding new treatments targeting cancer stem cells (CSCs) within a tumor seems to be critical to halt cancer and improve patient survival. Osteosarcoma is an aggressive tumor affecting adolescents, for which there is no second-line chemotherapy. Uncovering new molecular mechanisms underlying the development of osteosarcoma and origin of CSCs is crucial to identify new possible therapeutic strategies. Here, we aimed to characterize genetically and molecularly the human osteosarcoma 3AB-OS CSC line, previously selected from MG63 cells and which proved to have both in vitro and in vivo features of CSCs. Classic cytogenetic studies demonstrated that 3AB-OS cells have hypertriploid karyotype wit…
Effect of auxin on the mitotic cell cycle in cultured leaf segments at different stages of development in wheat
1987
Young leaves of Triticum timopheevi Zukh. show a defined gradient of development. One-mm-long sections from such leaves were cultured in vitro. At a low concentration of exogenous auxin, cells in the most basal, highly meristematic explants divided readily in culture, but in the absence of auxin they soon ceased dividing and were arrested in G1 and G2 of the mitotic cell cycle. In the region adjoining the meristem, where most cells were arrested in G1, very high concentrations of auxin had to be applied to reinitiate cell division, i.e. stimulate transitions from G1 to S-phase and from G2 to mitosis. Above this potentially auxin-responsive region, which represented less than 50% of the tota…
Identification of Novel Principles of Keratin Filament Network Turnover in Living Cells
2004
It is generally assumed that turnover of the keratin filament system occurs by exchange of subunits along its entire length throughout the cytoplasm. We now present evidence that a circumscribed submembranous compartment is actually the main site for network replenishment. This conclusion is based on the following observations in living cells synthesizing fluorescent keratin polypeptides: 1) Small keratin granules originate in close proximity to the plasma membrane and move toward the cell center in a continuous motion while elongating into flexible rod-like fragments that fuse with each other and integrate into the peripheral KF network. 2) Recurrence of fluorescence after photobleaching i…
El mito de la princesa: Blancanieves y la Bella Durmiente según Elfriede Jelinek
2011
Reescribir y reinterpretar cuentos tradicionales forma parte ya de una tradición literaria a la que no pocos autores se han sumado. El presente artículo ofrecerá un análisis de uno de estos intentos, llevado a cabo por la escritora austriaca Elfriede Jelinek. La autora ganadora del Premio Nobel de Literatura en 2004 publicó un año antes Dramas de princesas. La muerte y la doncella I-V, un conjunto de cinco obras concebidas como entreactos de otros espectáculos teatrales. De entre los modelos que la autora toma como referencia, los cuentos de hadas suponen el punto de partida para dos de los dramas, La muerte y la doncella I (Blancanieves) y La Muerte y la doncella II (La Bella Durmiente). E…
Características del alumnado con altas capcidades
2012
Se describen las características del alumnado con altas capacidades, la terminología más usual y la clasificación. Asimismo, se expone la teoría de la disincronía y los mitos relacionados con este alumnado.
High‐resolution histographical mapping of glucose concentrations in developing cotyledons of Vicia faba in relation to mitotic activity and storage p…
1998
Summary Previous studies provided evidence that the carbohydrate status triggers developmental processes in the growing cotyledons ofVicia faba. We describe here the high-resolution mapping of glucose concentrations in tissue sections of developing faba bean cotyledons by quantitative bioluminescence and single-photon imaging. Patterns of local glucose distributions are compared with tissue cell type, mitotic index and the distribution pattern of starch. During cotyledon differentiation, gradients in the glucose concentration emerge which are related to the particular cell type. Higher concentrations are found in non-differentiated premature regions of the cotyledon whereas mature starch-ac…
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.
Mitos del amor romántico y autoestima en adolescentes
2019
Los mitos del amor romántico son creencias irracionales socialmente construidas sobre la naturaleza del amor, las cuales estipulan qué es el “amor verdadero”, cuáles son las características deseables al seleccionar pareja, la importancia del amor, las expectativas de futuro y el tipo de relación. La presencia de estas creencias románticas favorece o mantiene la violencia de género en la pareja y las relaciones basadas en el control, las cuales se relacionan con una menor autoestima. El objetivo de este estudio es registrar la interiorización de los mitos del amor romántico en un grupo de adolescentes y analizar su relación con la autoestima. Para la consecución de dicho objetivo, una muestr…