Search results for " LAB"

Chemical Ligation and Isotope Labeling to Locate Dynamic Effects during Catalysis by Dihydrofolate Reductase.

2015

Abstract Chemical ligation has been used to alter motions in specific regions of dihydrofolate reductase from E. coli and to investigate the effects of localized motional changes on enzyme catalysis. Two isotopic hybrids were prepared; one with the mobile N‐terminal segment containing heavy isotopes (2H, 13C, 15N) and the remainder of the protein with natural isotopic abundance, and the other one with only the C‐terminal segment isotopically labeled. Kinetic investigations indicated that isotopic substitution of the N‐terminal segment affected only a physical step of catalysis, whereas the enzyme chemistry was affected by protein motions from the C‐terminal segment. QM/MM studies support th…

8-N(3)-3'-biotinyl-ATP, a novel monofunctional reagent: differences in the F(1)- and V(1)-ATPases by means of the ATP analogue.

2001

A novel photoaffinity label, 8-N(3)-3'-biotinyl-ATP, has been synthesized. The introduction of an additional biotin residue is advantageous for easy detection of labeled proteins. This could be first tested by reaction with the F(1)-ATPase from the thermophilic bacterium PS3 (TF(1)). UV irradiation of TF(1) in the presence of 8-N(3)-3'-biotinyl-ATP results in a nucleotide-dependent binding of the analogue in the noncatalytic alpha and the catalytic beta subunits of TF(1), demonstrating the suitability of this analogue as a potential photoaffinity label. Reaction with the V(1)-ATPase, however, led to labeling of subunit E, which has been suggested as a structural and functional homologue of …

Mapping of a binding site for ATP within the extracellular region of the Torpedo nicotinic acetylcholine receptor beta-subunit.

1997

Using 2,8,5'-[H-3]ATP as a direct photoaffinity label for membrane-bound nicotinic acetylcholine receptor (nAChR) from Torpedo marmorata, we have identified a binding site for ATP in the extracellular region of the beta-subunit of the receptor. Photolabeling was completely inhibited in the presence of saturating concentrations of nonradioactive ATP, whereas neither the purinoreceptor antagonists suramin, theophyllin, and caffeine nor the nAChR antagonists alpha-bungarotoxin and d-tubocurarine affected the labeling reaction. Competitive and noncompetitive nicotinic agonists and Ca2+ increased the yield of the photoreaction by up to 50%, suggesting that the respective binding sites are allost…

Moroccans and Ecuadorians in the Mediterranean litoral intensive agriculture

2002

Desde el final de los años 1990 hay cambios importantes en el panorama migratorio español. Entre éstos cabe destacar la llegada de nuevos colectivos y la generalización del fenómeno en regiones y en sectores económicos que hasta el momento no conocían la mano de obra extranjera. Entre los nuevos grupos sobresalen los ecuatorianos que ya son el segundo colectivo de extranjeros en España y que en ciertas zonas entran en competencia con los marroquíes. Esta situación se aprecia especialmente bien en las comarcas agrarias del litoral mediterráneo. Since the end of the 1990s, there have been significant changes in the Spanish migration scene. Among them it is important to highlight the arrival o…

Ekstracelulāro vezīkulu efekti uz Pārkinsona slimības modeļa žurku telpisko iemācīšanos un atmiņu

2019

Šī darba mērķis bija noteikt intranazāli ievadīto ekstracelulāro vezīkulu (EV) efektus uz telpisko iemācīšanos un atmiņu žurku Pārkinsona slimības modelī, izmantojot Morris ŪL testu. Iegūtie resultāti rāda, ka EVs būtiski uzlaboja Pārkinsona slimības modeļžurku īslaicīgo telpisko iemācīšanos, bet ne telpisko atmiņu. Pie tam, EVs neietekmēja Pārkinsona slimības modeļžurku telpisko iemācīšanos/atmiņu divas nedēļās pēc to ievadīšanas beigām. Iegūtie dati demonstrē, ka subhronisko EV ievadīšan varētu uzskatīt par daudzsološu stratēģiju pirmo atmiņas traucējumu novēršanā Pārkinsona slimības modeļžurkām, taču ir jāoptimizē EV ievadīšanas ilgums.

Does persistent employment instability affect fertility? A couple perspective

2014

2014

Division of labor is a defining characteristic of social insects and fundamental to their ecological success. Many of the numerous tasks essential for the survival of the colony must be performed at a specific location. Consequently, spatial organization is an integral aspect of division of labor. The mechanisms organizing the spatial distribution of workers, separating inside and outside workers without central control, is an essential, but so far neglected aspect of division of labor. In this study, we investigate the behavioral mechanisms governing the spatial distribution of individual workers and its physiological underpinning in the ant Myrmica rubra. By investigating worker personali…

LABCENTER. A remote laboratory system platform

2011

Abstract A web system server especially suited for remote laboratories has been developed. Typical e-learning systems do not offer the possibility to perform a remote laboratory where real experiments can be done online, accessing real hardware located at the University facilities. Allowing students to connect to hardware systems remotely provides them with additional knowledge about real devices; very often, real laboratory devices are time or space restricted. The proposed LABCENTER platform is a general frame designed for remote laboratories connection. The platform is designed to allow an authorized student to connect to hardware systems. As direct hardware systems allow only a single u…

Revista electrónica de investigación y evaluación educativa

2021

Background of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: Compilation Este artículo tiene dos objetivos. En primer lugar, queremos analizar si el peso del origen social de los graduados universitarios influye en la inserción laboral, tomando como indicador los ingresos que obtienen los titulados que trabajan, cuando controlamos la titulación obtenida. En segundo lugar, intentamos observar si los graduados universitarios provenientes de orígenes sociales más desfavorecidos se encuentran más desocupados y más inactivos que los provenientes de hogares con más recursos. Para tal fin analizamos a los titulados que egresaron de universidades públicas catalanas en el curso 2006-2007, entre…

Work stress and health problems of professional drivers: A hazardous formula for their safety outcomes

2018

BackgroundSeveral empirical studies have shown that professional drivers are a vulnerable occupational group, usually exposed to environmental stressors and adverse work conditions. Furthermore, recent studies have associated work-related stress with negative job performances and adverse health outcomes within this occupational group, including cardiovascular diseases and unsafe vehicle operation.ObjectiveThe aim of this study was to describe the working conditions and the health status of this occupational group, and to evaluate the association between the Demand–Control model of job stress and their self-reported health and safety outcomes.MethodsA pooled sample of 3,665 Colombian profess…