Search results for "Ciencias Biológicas"
showing 10 items of 794 documents
Solar UV-B radiation affects leaf quality and insect herbivory in the southern beech tree Nothofagus antarctica
2004
We examined the effects of solar ultraviolet-B (UV-B) radiation on plant-insect interactions in Tierra del Fuego (55°S), Argentina, an area strongly affected by ozone depletion because of its proximity to Antarctica. Solar UV-B under Nothofagus antarctica branches was manipulated using a polyester plastic film to attenuate UV-B (uvb-) and an Aclar film to provide near-ambient UV-B (uvb+). The plastic films were placed on both north-facing (i.e., high solar radiation in the Southern Hemisphere) and south-facing branches. Insects consumed 40% less leaf area from north- than from south-facing branches, and at least 30% less area from uvb+ branches than from uvb-branches. The reduced herbivory …
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…
Modulation of Diabetes by Natural Products and Medicinal Plants via Incretins
2019
Incretins are metabolic hormones released after a meal that increase insulin secretion from pancreatic β-cells. The two main incretins are the intestinal peptides glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. Both induce a decrease in glycemia, slow down the absorption of nutrients, and are inactivated by the enzyme dipeptidyl peptidase-4. Recently, incretin-based therapies have become a useful tool to treat diabetic patients, and different studies have focused on the identification of glucagon-like peptide-1 receptor agonists, including those of natural origin. This review focuses on the new findings of medicinal plants and natural products as possible active ag…
On the complexity of the Saccharomyces bayanus taxon: Hybridization and potential hybrid speciation
2014
Although the genus Saccharomyces has been thoroughly studied, some species in the genus has not yet been accurately resolved; an example is S. bayanus, a taxon that includes genetically diverse lineages of pure and hybrid strains. This diversity makes the assignation and classification of strains belonging to this species unclear and controversial. They have been subdivided by some authors into two varieties (bayanus and uvarum), which have been raised to the species level by others. In this work, we evaluate the complexity of 46 different strains included in the S. bayanus taxon by means of PCR-RFLP analysis and by sequencing of 34 gene regions and one mitochondrial gene. Using the sequenc…
Contribución al conocimiento de la flora alóctona abulense (Ávila, España)
2012
Se aportan datos corológicos de catorce plantas vasculares presentes en la provincia de Ávila (España). De ellas, cinco son primeras citas provinciales: Chamaesyce prostrata (Aiton) Small, Conyza sumatrensis (Retz.) E. Walker, Helianthus tuberosus L., Melia azedarach L. y Panicum miliaceum L. El resto de plantas vasculares no son muy conocidas en la zona. Para cada una de ellas se aporta información florística y bibliográfica.SUMMARY: Chorological data concerning fourteen species of invasive vascular plants in Ávila province (Spain) are shown. Among them, we must highlight Chamaesyce prostrata (Aiton) Small, Conyza sumatrensis (Retz.) E. Walker, Helianthus tuberosus L., Melia azedarach L. a…
El género "Urginea Steinh." (Hyacinthaceae) en la flora ibérica
1997
Se aportan datos diversos sobre los táxones del género Urginea Steinh. (Hyacinthaceae) presentes en la flora ibérica. Se propone la combinación Urginea undulata subsp. caeculi (Pau) M.B. Crespo & Mateo comb. nov., para las poblaciones ibéricas de la especie, y se tipifica dicho nombre. Además, se añade una clave para la identificación de los táxones considerados. Some data on taxa of Urginea Steinh. (Hyacinthaceae) found in the Iberian flora are reported. The combination Urginea undulata subsp. caeculi (Pau) M.B. Crespo & Mateo comb. nov., is proposed for the Spanish populations of the species, and that name is also typified. Moreover, a key is presented for identification of taxa.
Orthilia secunda (L.) House, nueva especie para la flora cantábrica
2014
P. 99-102 Hemos encontrado en un hayedo submesófilo basófilo orocantábrico una población de la especie Orthilia secunda (L.) House, novedad para la Cordillera Cantábrica y la mitad oeste peninsular. Se estudia la composición florística del sotobosque y se enfatiza la fragilidad de la comunidad derivada de las complejas relaciones tróficas micorríticas de las especies inventariadas. Se propone su inclusión en el Catálogo de Flora Protegida de Castilla y León. SI
Sobre la presencia actual de "Atropa baetica" Willk. (Solanaceae) en la Alta Alcarria (Utande, Guadalajara)
2016
Se da noticia del hallazgo y presencia actual de "Atropa baetica" Willk. (Solanaceae) en una localidad de la Alta Alcarria, municipio de Utande (provincia de Guadalajara). Se indica la cuadrícula U.T.M. de 1×1 km donde se encuentra. Se presentan datos ecológicos y fitogeográficos básicos sobre su emplazamiento, algunos datos vegetativos descriptivos de los dos rodales o conjuntos de tallos encontrados y comentarios sobre posibles amenazas de la escueta población. Finalmente, se comenta la relación de esta nueva cita con referencias antiguas publicadas en la bibliografía.
Molecular and enological characterization of a natural Saccharomyces uvarum and Saccharomyces cerevisiae hybrid
2015
Available online 17 March 2015
Taxonomic and nomenclatural novelties concerning the Valencian flora (eastern Spain)
2008
Como paso previo a la publicación de la cuarta edición del Manual para la determinación de la flora valenciana, que se encuentra en fase de edición, en la presente contribución se discute la identidad y valor taxonómico de algunas plantas iberolevantinas presentes en la Comunidad Valenciana. Como resultado se proponen cinco combinaciones nuevas, un nombre nuevo y se describen dos especies y una notospecie nuevas; asimismo se designan dos lectótipos. Para todas ellas se comentan aspectos nomenclaturales, taxonómicos, ecológicos y corológicos. Taxonomic and nomenclatural novelties concerning the Valencian flora (eastern Spain): Prior to publication of the fourth edition of Manual para la dete…