Search results for " Biologia"
showing 10 items of 700 documents
Caracterización estructural y funcional de los promotores humanos SREBP1 y su regulador INSIG2
2009
La homeostasis lipídica está regulada por factores de transcripción llamados Proteínas de unión a elementos de respuesta a esteroles ó SREBP. Estas porteínas activan a nivel transcripcional enzimas de las vías de síntesis de colesterol, ácidos grasos, triglicéridos y fosfolípidos. Además estos factores regulan la diferenciación adipocitaria y la expresión génica dependiente de insulina. Alteraciones funcionales en SREBP han sido relacionadas con el desarrollo de diversas patologías metabólicas humanas como la obesidad y la diabetes tipo 2. Existen tres miembros de la familia SREBP. Las variantes SREBP1a y SREBP1c, son producidas por splicing alternativo a partir de un único gen mientras que…
Cambios en la fosforilación de proteínas nucleares y cascadas de señalización inducidos por el ácido retinoico
2009
La vitamina A, a partir de una serie de transformaciones metabólicas, se convierte en el ácido retinoico (RA), su metabolito activo más potente biológicamente. La vitamina A y sus derivados juegan un importante papel como reguladores fisiológicos de un gran número de procesos biológicos. Concretamente, el RA posee un papel relevante en el desarrollo embrionario temprano y en la generación de varios órganos y sistemas, como es el caso del Sistema Nervioso. El RA es capaz de inducir la parada proliferativa y la diferenciación in vitro de líneas celulares de muy diferente origen, incluyendo muchos tipos celulares tumorales como el neuroblastoma. Estudios previos realizados en la línea celular …
Estudio teórico de procesos fotoinducidos en sistemas biológicos
2009
En la presente Tesis Doctoral se investiga, desde un punto de vista teórico, procesos de transferencia de carga y/o energía inducida por la luz en distintos sistemas biológicos. En concreto se estudian tres procesos paradigmáticos: la transferencia de carga en la fotosíntesis, la fotofísica y fotorreactividad de las bases nitrogenadas del DNA y el proceso de fotoisomerización del cromóforo de la Rodopsina, desencadenante de la visión. La metodología empleada para la realización de estos estudios es principalmente la CASPT2//CASSCF, una herramienta químico-cuántica especialmente adecuada para el tratamiento de los estados moleculares excitados, debido a su carácter multiconfiguracional.
Specific expression of a TRIM-containing factor in ectoderm cells affects the skeletal morphogenetic program of the sea urchin embryo
2011
In the indirect developing sea urchin embryo, the primary mesenchyme cells (PMCs) acquire most of the positional and temporal information from the overlying ectoderm for skeletal initiation and growth. In this study, we characterize the function of the novel gene strim1, which encodes a tripartite motif-containing (TRIM) protein, that adds to the list of genes constituting the epithelial-mesenchymal signaling network. We report that strim1 is expressed in ectoderm regions adjacent to the bilateral clusters of PMCs and that its misexpression leads to severe skeletal abnormalities. Reciprocally, knock down of strim1 function abrogates PMC positioning and blocks skeletogenesis. Blastomere tran…
Expression of homeobox-containing genes in the sea urchin (Parancentrotus lividus) embryo
1994
Two homeobox-containing genes that belong to different homeodomain classes have been isolated from a sea urchin geonomic library. One, PlHbox11, is the sea urchin homologue of the human and mouse Hox B3 gene, the other, PlHbox12, shows about 55% identity with paired class genes. Expression profile analysis of the two sea urchin Hbox genes suggests that they play different roles during embryogenesis. In fact, PlHbox11 transcripts are rare and are detected only in the pluteus larva and in the Aristotle's lantern and intestine of the adult. The PlHbox12 gene is, on the contrary, transiently expressed in the very early embryo already at the four cell stage; it accumulates at the 64 cell stage a…
Addition of either pioglitazone or a sulfonylurea in type 2 diabetic patients inadequately controlled with metformin alone: impact on cardiovascular …
2012
Abstract Background and aims Metformin is the first-line therapy in type 2 diabetes. In patients inadequately controlled with metformin, the addition of a sulfonylurea or pioglitazone are equally plausible options to improve glycemic control. However, these drugs have profound differences in their mechanism of action, side effects, and impact on cardiovascular risk factors. A formal comparison of these two therapies in terms of cardiovascular morbidity and mortality is lacking. The TOSCA.IT study was designed to explore the effects of adding pioglitazone or a sulfonylurea on cardiovascular events in type 2 diabetic patients inadequately controlled with metformin. Methods Multicentre, random…
Effects of GLP-1 receptor agonists on myokine levels and pro-inflammatory cytokines in patients with type 2 diabetes mellitus.
2021
Background and aims: To evaluate the change in circulating serum irisin and interleukin-6 (IL-6), in patients with type 2 diabetes mellitus (T2DM) after 6 and 12 months of GLP-1 treatment. Methods and results: Eighty-five patients with T2DM inadequately controlled with insulin or other hypoglycaemic drugs were added to dulaglutide (N° = 44) and liraglutide (N° = 41) treatment. After 6 months of GLP-1 analogues a significant decrease in BMI (p < 0.001), waist circumference (WC) (p < 0.001), fasting blood glucose (p < 0.001), HbA1c (p < 0.001), total cholesterol (p < 0.001), LDL-cholesterol (p = 0.003), triglycerides (p = 0.017), IL-6 (p = 0.045) and a significant increase in s…
Chemical Composition of the Essential Oils of Three Species of the Apiaceae Family Growing Wild in Sicily: Bonannia graeca, Eryngium maritimum and Op…
2013
n the present study the chemical composition of the essential oils from aerial parts of Bonannia graeca (L.) Halácsy and Opopanax chironium (L.) Kock, and from aerial parts and roots of Eryngium maritimum L. was evaluated by GC and GC-MS. α-Pinene (15.2%) and β-pinene were recognized as the main constituents of B. graeca, whereas the aerial parts of O. chironium contained mainly the diterpene cembrene and the coumarin angelicin. In both aerial parts and roots of E. maritimum germacrene D (10.4% and 15.9%, respectively) and 2,4,5-trimethylbenzaldehyde (8.3% and 6.7%) were the most abundant components
Synthesis and In Vitro Evaluation of a Photosensitizer-BODIPY Derivative for Potential Photodynamic Therapy Applications
2015
A new photosensitizer (1) based on the 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) scaffold has been synthesized. 1 is water soluble and showed an intense absorption band at 490 nm (e=77600 cm-1M-1) and an emission at 514 nm. In vitro toxicity of 1 in the presence of light and in darkness has been studied with HeLa, HaCaT, MCF-7, and SCC-13 cell lines. Moreover, internalization studies of 1 in these cell lines were also performed. These results suggested that 1 is more toxic for SCC-13 and HeLa carcinoma cells than for the HaCaT noncancerous immortal human keratinocytes. Toxicity upon light irradiation was due to the formation of singlet oxygen and reactive oxygen species (ROS). Cel…