2,044,495 research outputs found
Ligand-Specific Regulation of the Endogenous Mu-Opioid Receptor by Chronic Treatment with Mu-Opioid Peptide Agonist
Since the discovery of the endomorphins (EM), the postulated endogenous peptide agonists of the mu-opioid receptors, several analogues have been synthesized to improve their binding and pharmacological profiles. We have shown previously that a new analogue, cis-1S,2R-aminocyclohexanecarboxylic acid2-endomorphin-2 (ACHC-EM2), had elevated mu-receptor affinity, selectivity, and proteolytic stability over the parent compound. In the present work, we have studied its antinociceptive effects and receptor regulatory processes. ACHC-EM2 displayed a somewhat higher (60%) acute antinociceptive response than the parent peptide, EM2 (45%), which peaked at 10 min after intracerebroventricular (icv) administration in the rat tail-flick test. Analgesic tolerance developed to the antinociceptive effect of ACHC-EM2 upon its repeated icv injection that was complete by a 10-day treatment. This was accompanied by attenuated coupling of mu-sites to G-proteins in subcellular fractions of rat brain. Also, the density of mu-receptors was upregulated by about 40% in the light membrane fraction, with no detectable changes in surface binding. Distinct receptor regulatory processes were noted in subcellular fractions of rat brains made tolerant by the prototypic full mu-agonist peptide, DAMGO, and its chloromethyl ketone derivative, DAMCK. These results are discussed in light of the recently discovered phenomenon, that is, the “so-called biased agonism” or “functional selectivity
EXPTIME Tableaux for the Coalgebraic Mu-Calculus
The coalgebraic approach to modal logic provides a uniform framework that captures the semantics of a large class of structurally different modal logics, including e.g. graded and probabilistic modal logics and coalition logic. In this paper, we introduce the coalgebraic mu-calculus, an extension of the general (coalgebraic) framework with fixpoint operators. Our main results are completeness of the associated tableau calculus and EXPTIME decidability. Technically, this is achieved by reducing satisfiability to the existence of non-wellfounded tableaux, which is in turn equivalent to the existence of winning strategies in parity games. Our results are parametric in the underlying class of models and yield, as concrete applications, previously unknown complexity bounds for the probabilistic mu-calculus and for an extension of coalition logic with fixpoints
Enriching OCL Using Observational Mu-Calculus
The Object Constraint Language is a textual specification language which forms part of the Unified Modelling Language[ 8 ]. Its principal uses are specifying constraints such as well-formedness conditions (e.g. in the definition of UML itself) and specifying contracts between parts of a system being modelled in UML. Focusing on the latter, we propose a systematic way to extend OCL with temporal constructs in order to express richer contracts. Our approach is based on observational mu-calculus, a two-level temporal logic in which temporal features at the higher level interact cleanly with a domain specific logic at the lower level. Using OCL as the lower level logic, we achieve much improved expressiveness in a modular way. We present a unified view of invariants and pre/post conditions, and we show how the framework can be used to permit the specification of liveness properties
Estimation of evapotranspiration in the Mu Us Sandland of China
Evapotranspiration (ET) was estimated from 1981–2005 over Wushen County located in the Mu Us Sandland, China, by applying the Advection-Aridity model, which is based on the complementary relationship hypothesis. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS), and meteorological data. Our results show that the estimated daily ET was about 4.5% higher than measurements using an Eddy Covariance (EC) system after forcing energy balance closure over an alfalfa field from 22 July 2004 to 23 August 2004. At a regional scale, the estimated monthly ET was about 8.7% lower than measurements using the EC system after forcing energy balance closure over an alfalfa field in August 2004. These results were about 3.0% higher than ET measurements by microlysimeter over sand dunes during June 1988. From 1981 to 2005, the average annual ET and precipitation levels were 287 mm and 336 mm, respectively, in Wushen County. The average annual ET varied from 230 mm in western parts of Wushen County to 350 mm in eastern parts of the county. Both inter-annual and seasonal variations in ET were substantial in Wushen County. The annual ET was 200–400 mm from 1981–2005, and the seasonal pattern of ET showed a single peak distribution. The cumulative ET during the June–September 2004 period was 250 mm, which was 87% of the total annual ET. The annual ET, precipitation, and the maximum Normalized Difference Vegetation Index (NDVI<sub>max</sub>) showed positive correlations temporally and spatially
Social trauma and the mu-opioid system in depression
The overarching thesis under investigation is that the endogenous opioid system plays a key role in depression subsequent to traumatic childhood social experiences. This is suggested by the fact that animal work indicates that mu-opioids robustly mediate separation-distress, and that early social stressors lead to long term dysregulation in key related circuitries and neuroanatomical structures
Recommended from our members
Times-Mu-Ta-Tion
Art work in Video and Audio surround installation (PVC pipes, zip ties, projection, speakers) by artist Jae-Eun Suh, as part of 2023 MFA exhibition entitled: "Times-Mu-Ta-Tion" in the Cora Stafford Gallery South, College of Visual Arts & Design, 1201 W Mulberry St, Denton, Texas, from April 19 - April 22, 2023
Recommended from our members
Times-Mu-Ta-Tion
Works of art of video by artist Jae-Eun Suh, as part of 2023 MFA exhibition entitled: "Times-Mu-Ta-Tion" in the Cora Stafford Gallery South, College of Visual Arts & Design, 1201 W Mulberry St, Denton, Texas, from April 19 - April 22, 2023
Recommended from our members
Times-Mu-Ta-Tion
Art work in Video and Audio surround installation (PVC pipes, zip ties, projection, speakers) by artist Jae-Eun Suh, as part of 2023 MFA exhibition entitled: "Times-Mu-Ta-Tion" in the Cora Stafford Gallery South, College of Visual Arts & Design, 1201 W Mulberry St, Denton, Texas, from April 19 - April 22, 2023
- …
