Search results for "Bioquímica"
showing 10 items of 221 documents
Ionic self-complementarity induces amyloid-like fibril formation in an isolated domain of a plant copper metallochaperone protein
2004
This article is available from: http://www.biomedcentral.com/1472-6807/4/7
Bioelectrical model of head-tail patterning based on cell ion channels and intercellular gap junctions
2020
Robust control of anterior-posterior axial patterning during regeneration is mediated by bioelectric signaling. However, a number of systems-level properties of bioelectrochemical circuits, including stochastic outcomes such as seen in permanently de-stabilized "cryptic" flatworms, are not completely understood. We present a bioelectrical model for head-tail patterning that combines single-cell characteristics such as membrane ion channels with multicellular community effects via voltage-gated gap junctions. It complements the biochemically-focused models by describing the effects of intercellular electrochemical coupling, cutting plane, and gap junction blocking of the multicellular ensemb…
Interaction of Bacillus thuringiensis Cry1 and Vip3A Proteins with Spodoptera frugiperda Midgut Binding Sites
2009
ABSTRACT Vip3Aa, Vip3Af, Cry1Ab, and Cry1Fa were tested for their toxicities and binding interactions. Vip3A proteins were more toxic than Cry1 proteins. Binding assays showed independent specific binding sites for Cry1 and Vip3A proteins. Cry1Ab and Cry1Fa competed for the same binding sites, whereas Vip3Aa competed for those of Vip3Af.
Assessing autophagy in archived tissue or how to capture autophagic flux from a tissue snapshot
2020
This article belongs to the Special Issue Autophagy in Cancer.
An overview of doping in sports
2019
The history of doping field can be outlined in three major stages: (1) early stage in which drug abuse took place during sports performance and competition and gas chromatography was used for its detection; (2) approximately in the 1970s when androgenic anabolic steroids were introduced; (3) In the recent era when the fields of biochemistry, physiology, toxicology, genomics, genetics, immunology, and molecular biology were integrated and applied routinely. Advanced omics technology and gene doping age may be applied in near future. This review will discuss commonly abused materials, both their adverse and harmful effects, and the alleged benefits in conjunction with the current standards in…
Specific binding of radiolabeled Cry1Fa insecticidal protein from Bacillus thuringiensis to midgut sites in lepidopteran species
2012
ABSTRACT Cry1Fa insecticidal protein was successfully radiolabeled with 125 I-Na. Specific binding to brush border membrane vesicles was shown for the lepidopteran species Ostrinia nubilalis , Spodoptera frugiperda , Spodoptera exigua , Helicoverpa armigera , Heliothis virescens , and Plutella xylostella . Homologous competition assays were performed to obtain equilibrium binding parameters ( K d [dissociation constant] and R t [concentration of binding sites]) for these six insect species.
Sistemas de dos componentes: Búsqueda de inhibidores, caracterización estructural y nuevos mecanismos de señalización
2011
En la última mitad de los años ochenta emergió el término “dos componentes” para describir una nueva clase de sistemas de transducción de señal encontrados en bacterias. Los sistemas de dos componentes (TCS) responden a múltiples estímulos, controlando a su vez una amplia variedad de procesos esenciales para la célula. El sistema prototipo consta de dos proteínas: Una histidina quinasa (HK) y un reguladora de la respuesta (RR). En general la transducción de la señal en un TCS incluye tres reacciones: la autofosforilación en un residuo de histidina específico de una HK dímerica, posteriormente este mismo grupo fosforilo es transferido a un aspartato del correspondiente RR, y finalmente el RR…
Interacciones entre activadores y represores en el inicio de la transcripción en Saccharomyces cerevisiae
2010
Autosomic dominant lateral temporal epilepsy (ADLTE) is a form of partial epilepsy with secondary generalized seizures, caused by mutations in LGI1. This gene was initially identified in 1998, as a tumour suppressor in multiform glioblastoma, affecting to the malignancy of these tumours. In silico analysis of the primary sequence of LGI1, revealed four paralogues of the gene, which shared a very similar domain structure and were named as LGI1, LGI2, LGI3 and LGI4. The existence of similar types of epilepsy with common features for that seen for ADLTE, suggests that some other members of this gene family could be involved in these pathologies. Moreover, the presence of four paralogues, makes…
Efectos moduladores del etanol sobre el sistema inmunitario: papel de los receptores TLR4
2010
Trabajos clínicos y experimentales han demostrado que el etanol altera al sistema inmunitario. Aunque los mecanismos moleculares se desconocen, se ha demostrado que sus acciones sobre el sistema inmunitario son complejas y dependen de la dosis, el tiempo de exposición (agudo o crónico), tipo celular y presencia o ausencia de estímulos adicionales, como patógenos. Evidencias recientes indican el papel de los receptores tipo Toll (TLR) en la respuesta inmunitaria innata y, posiblemente, en la adquirida. De hecho, el tratamiento agudo de alcohol parece inhibir la respuesta inflamatoria y la liberacion de citocinas mediada por los receptores TLR en macrófagos. Por el contrario, el tratamiento c…
Determinantes de la osteoporosis posmenopáusica: aspectos genéticos e inmunológicos y modulación por diferentes tratamientos
2010
La pérdida ósea acelerada puede desencadenar en osteoporosis, una enfermedad esquelética caracterizada por una menor resistencia ósea y riesgo aumentado de fractura. Es la enfermedad metabólica más prevalente entre la población femenina ya que afecta al 35% de las mujeres españolas mayores de 50 años, y por lo tanto es un problema de salud pública muy importante. El tipo de osteoporosis más frecuente es la osteoporosis posmenopáusica, una enfermedad multigénica que se inicia con la retirada de la protección estrogénica. No obstante, a pesar de que todas las mujeres aceleran su tasa de pérdida ósea con la menopausia, no todas desarrollarán osteoporosis en el futuro. La causa hay que buscarla…