Search results for "competitive"
showing 10 items of 720 documents
In Vivo Molecular Imaging of Somatostatin Receptors in Pancreatic Islet Cells and Neuroendocrine Tumors by Miniaturized Confocal Laser-Scanning Fluor…
2010
The aim of the study was to evaluate real time in vivo molecular imaging of somatostatin receptors (sstrs) using a handheld miniaturized confocal laser scan microscope (CLM) in conjunction with fluorescein-labeled octreotate (OcF) in healthy mice and murine models of neuroendocrine tumors. For CLM a small rigid probe (diameter 7 mm) with an integrated single line laser (488 nm) was used (optical slice thickness 7 μm; lateral resolution 0.7 μm). OcF was synthesized via Fmoc solid-phase peptide synthesis and purified by HPLC showing high-affinity binding to the sstr2 (IC50 6.2 nmol). For in vitro evaluation, rat and human pancreatic cancer cells were used and characterized with respect to its…
Antipsychotic drugs antagonize human serotonin type 3 receptor currents in a noncompetitive manner
2004
The serotonin type 3 (5-HT(3)) receptor is the only ligand-gated ion channel receptor for serotonin (5-HT). 5-HT(3) receptors play an important role in modulating the inhibitory action of dopamine in mesocorticolimbic brain regions. Neuroleptic drugs are commonly thought to exert their psychopharmacological action mainly through dopamine and serotonin type 2 (5-HT(2)) receptors. Except for clozapine, a direct pharmacological interaction of neuroleptics with 5-HT(3) receptors has not yet been described. Using the concentration-clamp technique, we investigated the effects of flupentixol, various phenothiazines, haloperidol, clozapine and risperidone on Na(+)-inward currents through 5-HT(3) re…
Pharmacological comparison of rat and human melanocortin 3 and 4 receptors in vitro.
2002
Abstract The melanocortin 3 and 4 receptors are G-protein-coupled receptors found in the hypothalamus with important role in regulation of the energy balance. In this study, we performed pharmacological comparison of the rat and human melancortin (MC) 3 and MC4 receptors. We transiently expressed the genes for these receptors individually in a mammalian cell line and determined the binding affinities to several MSH peptides. The results showed no major difference between the rat and human MC3 receptors while the rat MC4 receptor had higher affinity to several peptides compared with the human MC4 receptor. NDP-, α-, β-, γ-MSH, ACTH(1–24), HS014 and MTII had from 5- to 34-fold higher affinity…
Feasibility and diagnostic performance of including point-of-care ultrasound (POCUS) in preparticipation screening of young competitive athletes
2020
AbstractOptimal pre-participative screening in young athletes is still controversial. We sought to evaluate the strategy of including point-of-care ultrasound to electrocardiogram. In total, 1188 young competitive athletes were screened in different sports institutions. This proved to be a useful strategy by improving diagnostic performance primarily with respect to detect structural abnormalities and also by minimising positive false cases of electrocardiogram alone.
Synthesis and in vitro evaluation of (S)-2-([11C]methoxy)-4-[3-methyl-1-(2-piperidine-1-yl-phenyl)-butyl-carbamoyl]-benzoic acid ([11C]methoxy-repagl…
2004
The 11 C-labeled sulfonylurea receptor 1 (SUR1) ligand (S)-2-(( 11 C)methoxy)-4-(3-methyl-1-(2-piperidine-1-yl-phenyl)- butyl-carbamoyl)-benzoic acid (( 11 C)methoxy-repaglinide) was synthesized in an overall radiochemical yield of 35% after 55 min with a radiochemical purity higher than 99%. This compound is considered for the noninvasive investigation of the SUR1 receptor status of pancreatic b-cells by positron emission tomography (PET) in the context of type 1 and type 2 diabetes. The specific activity was 40-70 GBq/lmol. In vitro testing of the nonradioactive methoxy-repaglinide was performed to characterize the affinity for binding to the human SUR1 isoform. Methoxy-repaglinide induce…
Selected peptides targeted to the NMDA receptor channel protect neurons from excitotoxic death
1998
Excitotoxic neuronal death, associated with neurodegeneration and stroke, is triggered primarily by massive Ca2+ influx arising from overactivation of glutamate receptor channels of the N-methyl-D-aspartate (NMDA) subtype. To search for channel blockers, synthetic combinatorial libraries were assayed for block of agonist-evoked currents by the human NR1-NR2A NMDA receptor subunits expressed in amphibian oocytes. A set of arginine-rich hexapeptides selectively blocked the NMDA receptor channel with IC50 approximately 100 nM, a potency similar to clinically tolerated blockers such as memantine, and only marginally blocked on non-NMDA glutamate receptors. These peptides prevent neuronal cell d…
Effects of Different Neuromuscular Electrical Stimulation Parameters on Quadriceps Neuromuscular Performance in Competitive Athletes
2017
PURPOSE: To evaluate the effects of six weeks of training with two different types of neuromuscular electrostimulation (NMES) currents on muscle performance in competitive athletes. METHODS: This controlled and randomized clinical trial included 20 athletes, equally divided into three groups: medium frequency current group with 500 μs (MF-500) (n=7), low frequency current group of with 500 μs (PC-500) (n=5) and control group (CG) (n=8). Each group had evaluated, before and after the intervention: the peak torque of knee (PT), muscle thickness and signs of electromyography (EMG) of the vastus lateralis (VL), and the sensory discomfort level (VAS). The training with NMES was performed 3 times…
Role of insulin-like growth factors in autocrine growth of human retinoblastoma Y79 cells.
1996
In this study, we have demonstrated that human retinoblastoma Y79 cells produce insulin-like growth factors (IGFs) type I and type II and release them into the medium. We have also ascertained, by means of competitive studies and cross-linking procedure, that Y79 cells contain the type-I IGF receptor (IGF-IR). Furthermore, surface-bound IGF-I is internalised by the receptor, then degraded to amino acids. Insulin, IGF-I and IGF-II caused down-regulation of IGF-IR; the effect is concentration and time dependant. Scatchard analysis demonstrated that incubation with insulin markedly decreased the binding capacity measured for IGF-I while the apparent Kd value calculated for IGF-I binding was no…
Synthesis of biotin-labelled dexamethasone derivatives. Novel hormone-affinity probes.
1983
A new, general methodology for 'sandwich' affinity chromatography of steroid hormone receptors is proposed, the part purification of the human spleen tumor glucocorticoid receptor is quoted as an illustration. 9-Fluoro-16 alpha-methyl-11 beta, 17-dihydroxy-1,4-androstadiene-3-one-17 beta-carboxylic acid was coupled to biotin using pentamethylenediamine (BioDex 1) as a spacer. The bifunctional derivative binds to glucocorticoid receptors and avidin-Sepharose and efficiently protects the glucocorticoid receptor against inactivation when previously added during homogenisation. We have standardized the capacity and optimum conditions for elution of receptor-BioDex-1 complexes which are bound to…
Mast cell growth-enhancing activity (MEA) is structurally related and functionally identical to the novel mouse T cell growth factor P40/TCGFIII (int…
1990
We have previously shown that certain bone marrow-derived mast cell (BMMC) lines proliferate in response to a mast cell growth-enhancing activity (MEA) that is distinct from interleukin (IL) 3 and IL 4. Here we provide evidence that MEA is identical with the recently cloned mouse T cell growth factor P40. The evidence is as follows: (a) recombinant P40 displayed all the biological activities ascribed to MEA: it supported the growth of MEA-sensitive BMMC lines, it induced IL 6 secretion by these cells, and it enhanced survival of primary mast cell cultures; (b) highly purified MEA stimulated the growth of P40-dependent cell lines; (c) a rabbit monospecific antiserum directed against P40 spec…