Search results for "Embryology"
showing 10 items of 198 documents
Impact of Ultrabithorax alternative splicing on Drosophila embryonic nervous system development.
2015
Hox genes control divergent segment identities along the anteroposterior body axis of bilateral animals by regulating a large number of processes in a cell context-specific manner. How Hox proteins achieve this functional diversity is a long-standing question in developmental biology. In this study we investigate the role of alternative splicing in functional specificity of the Drosophila Hox gene Ultrabithorax (Ubx). We focus specifically on the embryonic central nervous system (CNS) and provide a description of temporal expression patterns of three major Ubx isoforms during development of this tissue. These analyses imply distinct functions for individual isoforms in different stages of n…
Chromatin dynamics of the developmentally regulated P. lividus neural alpha tubulin gene
2011
Over 40 years ago, Allfrey and colleagues (1964) suggested that two histone modifications, namely acetylation and methylation, might regulate RNA synthesis. Nowadays it is universally accepted that activation of gene expression strictly depends on enzymatic mechanisms able to dynamically modify chromatin structure. Here, using techniques including DNaseI hypersensitive site analysis, chomatin immunoprecipitation and quantitative PCR analysis, we have analyzed the dynamics of histone post-translation modifications involved in developmentally/spatially controlled activation of the sea urchin PlTalpha2 tubulin gene. We have demonstrated that only when the PlTalpha2 core promoter chromatin is a…
Manufacturing, characterization and control of cell-based medicinal products: challenging paradigms toward commercial use
2015
During the past decade, a large number of cell-based medicinal products have been tested in clinical trials for the treatment of various diseases and tissue defects. However, licensed products and those approaching marketing authorization are still few. One major area of challenge is the manufacturing and quality development of these complex products, for which significant manipulation of cells might be required. While the paradigms of quality, safety and efficacy must apply also to these innovative products, their demonstration may be demanding. Demonstration of comparability between production processes and batches may be difficult for cell-based medicinal products. Thus, the development …
Cloning and expression of the sponge longevity gene SDLAGL.
2000
Porifera show a characteristic Bauplan in spite of the fact that (almost) all cells are telomerase-positive and presumably provided with an unlimited potency for cell proliferation. One gene, SDLAGL, was identified in the marine sponge Suberites domuncula whose deduced polypeptide showed high sequence similarity to the longevity assurance genes from other Metazoa. While in single cells no transcripts of SDLAGL could be identified, high expression was seen after re-aggregation of single cells and in proliferating cells of primmorphs.
Embryo development in Cocos nucifera L.: A critical contribution to a general understanding of palm embryogenesis
1979
InCocos (and probably in all other palms) the embryogenesis shows a number of primitive characters, such as differentiation of the embryo proper from one cell of the pluricellular proembryo, origin of the single cotyledon from a position lateral to the terminal stem tip, and a tendency to cleavage polyembryony.
Violence in the Brothers Grimm's fairy tales: a corpus-based approach
2010
The purpose of this article is to carry out a corpus-based study on the presence of violence in a selection of eight tales by the Grimm's Brothers by looking at the terms which can be said to relate to the semantic field of violence. More specifically, this study will analyse a selection of eight tales in which the frequency of the words cut, dead and blood will be studied in detail. These words have been chosen due to their possible connection to violence after carrying out a quantitative analysis of the frequency of the whole main corpus. My initial hypothesis is that the corpus-based study of those eight tales would support my intuition regarding the high percentage of violence in the Br…
In vivo fate mapping with SCL regulatory elements identifies progenitors for primitive and definitive hematopoiesis in mice.
2009
10 páginas, 6 figuras.-- et al.
HeterozygousFGF8mutations in patients presenting cryptorchidism and multiple VATER/VACTERL features without limb anomalies
2014
Background The acronym VATER/VACTERL association describes the combination of at least three of the following cardinal features: vertebral defects, anorectal malformations, cardiac defects, tracheoesophageal fistula with or without esophageal atresia, renal malformations, and limb defects. Although fibroblast growth factor-8 (FGF8) mutations have mainly found in patients with Kallmann syndrome, mice with a hypomorphic Fgf8 allele or complete gene invalidation display, aside from gonadotropin-releasing hormone deficiency, parts or even the entire spectrum of human VATER/VACTERL association. Methods We performed FGF8 gene analysis in 49 patients with VATER/VACTERL association and 27 patients …
Beitrag zur Entwicklungsgeschichte der Nasenregion des Elches (Alces alces L.)
1928
Izvilkums no: Zeitschrift für Morphologie und Ökologie der Tiere, 13. Bd., 1./2. Heft, 1928.
The oxidizing agent tertiary butyl hydroperoxide induces disturbances in spindle organization, c-meiosis, and aneuploidy in mouse oocytes
1996
It has been recently proposed that a concomitant generation of oxidative stress of oocytes with increasing maternal age may be a major factor responsible for the age-related increase in aneuploid conceptions. As a preliminary step in the testing of this hypothesis, we need to confirm that oxidative stress in itself can induce errors in chromosome segregation. In order to achieve this goal, germinal vesicle (GV)-stage mouse oocytes from unstimulated ICR and (C57BL x CBA) F1 hybrid female mice were matured in vitro for 9 h for metaphase I (MI) oocytes or 16 h for metaphase II (MII) oocytes in the presence of varying concentrations of the oxidizing agent tertiary-butyl hydroperoxide (tBH). MII…