Search results for "Embryology"

Overexpression of the truncated form of high mobility group a proteins (HMGA2) in human myometrial cells induces leiomyoma-like tissue formation

2014

The pathogenesis of uterine leiomyomas, the most common benign tumor in women, is still unknown. This lack of basic knowledge limits the development of novel non-invasive therapies. Our group has previously demonstrated that leiomyoma side population (SP) cells are present in tumor lesions and act like putative tumor-initiating stemcells in human leiomyoma. Moreover, accumulated evidence demonstrates that these benign tumors of mesenchymal origin are characterized by rearrangements of the High Mobility Group A proteins (HMGA). In this work, we tested the hypothesis that leiomyoma development may be due to overexpression of HMGA2 (encoding high mobility group AT-hook2) in myometrial stem cel…

Light and electron microscopical demonstration of methylene blue accumulation sites in taste buds of fish and mouse after supravital dye injection

1995

Electron microscopical data regarding methylene blue staining of taste buds in the epithelia of the goldfish lip and the cirumvallate papilla of the mouse tongue after supravital dye application are presented for the first time. The ultrastructural details were compared with the corresponding light microscopical findings. The dye was applied in different concentrations by injection or in crystalline from directly to the surface of the tissues. Both methylene blue and tissue were simultaneously fixed by immersion in a paraformaldehyde-glutaraldehyde solution with the addition of phosphomolybdic acid. The ensuing dye precipitate was further stabilized by ammonium heptamolybdate. On the light …

Cellular and Molecular Mechanism of Spinal Cord Regeneration in the Frog Xenopus laevis

2017

Los catálogos de museo, una gran oportunidad para el conocimiento abierto¿ si se abren

2020

El patrimonio textil es uno de los varios "primos pobres" dentro de la gran familia del patrimonio cultural. Algo especialmente lamentable, pues pocas partes del regis-tro histórico o cultural son tan transversales como los tejidos, tan ricas en información social y connotaciones culturales, técnicas y vitales. Tradicionalmente la seda ha tenido un lugar principal, como tejido de lujo, cuyos productos eran el máximo de las posibilidades mate-riales y culturales de muchas sociedades. Esto hace también que los objetos de seda sean especialmente abundantes en muchas colecciones históricas; no solo por la indumentaria, sino como parte de objetos funcio-nales, simbólicos, litúrgicos, mobiliario,…

Immunohistochemistry of cholinergic receptors.

1992

Acetylcholine and its receptors are involved in a variety of important signal transduction processes. As shown here paradigmatically for the human neuromuscular junction and the cerebral cortex, acetylcholine receptors can be visualized immunohistochemically at the cellular and subcellular level under physiological and pathological conditions. At normal motor endplates nicotinic cholinoceptors are localized at the surface of the postsynaptic junctional folds. In myasthenic syndromes investigation of muscle biopsies enables the diagnosis of receptor deficiencies at the ultrastructural level. In normal cerebral cortex pyramidal neurons are equipped with both nicotinic and muscarinic acetylcho…

Isolation of fibroblasts for coating of meshes for reconstructive surgery: differences between mesh types.

2009

Aims: An extensive colonization of surgical meshes with autologous fibroblasts may reduce complications. Therefore, we aimed to establish a technique that allows isolation and propagation of fibroblasts from vaginal biopsies. Using these cells we tested the applicability of several clinically applied meshes for fibroblast coating. Materials & methods: Fibroblasts were isolated from vaginal tissue after digestion with collagenase. Characterization was performed by immunostaining for cytokeratin 5, 6 and 14, smooth muscle actin and vimentin. A semiquantitative technique was applied to determine the degree of mesh coating 5 h and 5 weeks after seeding of fibroblasts. Seven meshes of diffe…

The pia mater at the site of the entry of blood vessels into the central nervous system

1982

The entry of blood vessels into the central nervous system (CNS) has been studied at the surface of the brain stem and the spinal cord of two cats and two rabbits. The study was carried out by scanning electron microscopy (SEM). The results obtained by SEM concerning the layers of the pia mater corresponded to those obtained by other authors who used transmission electron microscopy. Between the basal lamina of the superficial glial membrane of the CNS and the cells lining the subarachnoid space, a pial connective tissue space could be clearly recognized. The blood vessles crossing the subarachnoid space were also covered by leptomeningeal lining cells. At the site of entry of these blood v…

Quantitative electron microscopic observations on Paneth cells of germfree and ex-germfree Wistar rats.

1986

Ultrastructural changes of Paneth cells of germfree (Gf) rats which had been inoculated with bacteria-containing feces from conventionally-reared (SPF) rats were quantitatively examined. 12 and 24 h after inoculation, the Paneth cells showed a striking decrease in the number of secretory granules and the occurrence of large vacuoles. Phagosomes containing bacteria were not seen. After 4 days, the secretory granules reaccumulated and smooth-surfaced apical vesicles increased in number. It is discussed that the large vacuoles may be related to membrane-retrieval events following the massive extrusion of secretory granules whereas the apical vesicles appear to serve this function when exocytos…

Histopathological and immunohistochemical aspects of bone tissue in aseptic necrosis of the femoral head

2021

Femoral head osteonecrosis, also known as avascular necrosis, is a disease with a multifactorial etiology, characterized by a profound change of bone architecture, which leads to the diminishing of bone resistance and femoral head collapse. The main causes that lead to femoral head necrosis are represented by the decrease of local blood perfusion and increase of intraosseous pressure, because of an excessive development of adipose tissue in the areolas of the trabecular bone tissue in the femoral head. The histopathological and immunohistochemical (IHC) study performed by us showed that most of bone trabeculae were damaged by necrotic-involutive processes, their sizes being reduced, both re…

Las ruinas de Belchite: de símbolo de la 'barbarie roja' a monumento por la paz

2021

La Batalla de Belchite (Zaragoza) fue una de las más cruentas de la Guerra Civil Española.  En 1939 se ordenó la conservación de las ruinas provocadas por la guerra, que fueron significadas como un símbolo de la "barbarie roja"en contraposición a un nuevo pueblo levantado como reflejo de un nuevo orden. En 1964 se abandonó definitivamente el pueblo viejo comenzó un proceso de degradación y expolio de sus ruinas acompañado de un nuevo discurso generado por los XXV años de paz que trataba de alejar la mirada a los dramas de la guerra y la postguerra. La llegada de la democracia acaba con la dictadura miltar y posibilita la revisión del relato histórico y una nueva recepción y resignificación …