Search results for "Prague"
showing 10 items of 652 documents
Synthesis and Pharmacological Activities of Novel 3-(Isoxazol-3-yl)-quinazolin-4(3H)-one Derivatives
1999
Several new 3-(isoxazol-3-yl)-quinazolin-4(3H)-one derivatives were synthesized and tested for their analgesic and antiinflammatory activities, as well as for their acute toxicity and ulcerogenic effect. A few compounds were as active as phenylbutazone in the writhing and acetic acid peritonitis tests. They had a very low ulcerogenic effect.
Discovery and SAR Evolution of Pyrazole Azabicyclo[3.2.1]octane Sulfonamides as a Novel Class of Non-Covalent N-Acylethanolamine-Hydrolyzing Acid Ami…
2021
Inhibition of intracellular N-acylethanolamine-hydrolyzing acid amidase (NAAA) activity is a promising approach to manage the inflammatory response under disabling conditions. In fact, NAAA inhibition preserves endogenous palmitoylethanolamide (PEA) from degradation, thus increasing and prolonging its anti-inflammatory and analgesic efficacy at the inflamed site. In the present work, we report the identification of a potent, systemically available, novel class of NAAA inhibitors, featuring a pyrazole azabicyclo[3.2.1]octane structural core. After an initial screening campaign, a careful structure–activity relationship study led to the discovery of endo-ethoxymethyl-pyrazinyloxy-8-azabicyclo…
Evaluation of genotoxicity and DNA protective effects of mangiferin, a glucosylxanthone isolated from Mangifera indica L. stem bark extract.
2012
Abstract Mangiferin is a glucosylxantone isolated from Mangifera indica L. stem bark. Several studies have shown its pharmacological properties which make it a promising candidate for putative therapeutic use. This study was focused to investigate the in vitro genotoxic effects of mangiferin in the Ames test, SOS Chromotest and Comet assay. The genotoxic effects in bone marrow erythrocytes from NMRI mice orally treated with mangiferin (2000 mg/kg) were also evaluated. Additionally, its potential antimutagenic activity against several mutagens in the Ames test and its effects on CYP1A1 activity were assessed. Mangiferin (50–5000 μg/plate) did not increased the frequency of reverse mutations …
Antimutagenic effects of flavonoids, chalcones and structurally related compounds on the activity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and…
1993
Abstract Sixty-four flavonoids were tested for their antimutagenic potencies with respect to IQ in Salmonella typhimurium TA98 and in part also towards MeIQ, MeIQx, Trp-P-2, and Glu-P-1 and in S. typhimurium TA100. Antimutagenic potencies were quantified by the inhibitory dose for 50% reduction of mutagenic activity (ID 50 ). A carbonyl function at C-4 of the flavane nucleus seems to be essential for antimutagenicity: two flavanols and four anthocyanidines were inactive. Again, five isoflavons, except biochanin A, were inactive. Within the other groups of 21 flavones, 16 flavonols and 16 flavanones the parent compounds flavone, flavonol, and flavonone possessed the highest antimutagenic pot…
Bisdihydrodiols, rather than dihydrodiol oxides, are the principal microsomal metabolites of tumorigenic trans-3,4-dihydroxy-3,4-dihydrodibenz[a,h]an…
1994
Several studies on metabolism and biological activity of tumorigenic dibenz[a,h]anthracene (DBA) and its derivatives have led to the conclusion that the M-region dihydrodiol, trans-3,4-dihydroxy-3,4-dihydro-DBA (DBA-3,4-dihydrodiol), is the precursor of the ultimate mutagenic and tumorigenic metabolite of DBA with the presumed structure of a bay-region dihydrodiol oxide. Incubations of DBA-3,4-dihydrodiol (50 microM) with the microsomal hepatic fraction of Sprague-Dawley rats pretreated with Aroclor 1254 yielded more than 13 metabolites upon separation by HPLC. anti-3,4-Dihydroxy-1,2-epoxy-1,2,3,4-tetrahydro-DBA [0.27 nmol/(nmol of P450.15 min)] could be identified for the first time by UV …
The 3,4-oxide is responsible for the DNA binding of benzo[ghi]perylene, a polycyclic aromatic hydrocarbon without a “classic” bay-region
2008
Abstract The polycyclic aromatic hydrocarbon (PAH) benzo[ghi]perylene (BghiP) lacks a “classic” bay-region and is therefore unable to form vicinal dihydrodiol epoxides thought to be responsible for the genotoxicity of carcinogenic PAHs like benzo[a]pyrene. The bacterial mutagenicity of BghiP increases considerably after inhibition of the microsomal epoxide hydrolase (mEH) indicating arene oxides as genotoxic metabolites. Two K-region epoxides of BghiP, 3,4-epoxy-3,4-dihydro-BghiP (3,4-oxide) and 3,4,11,12-bisepoxy-3,4,11,12-tetrahydro-BghiP (3,4,11,12-bisoxide) identified in microsomal incubations of BghiP are weak bacterial mutagens in strain TA98 of Salmonella typhimurium with 5.5 and 1.5…
The new radioligand [H-3]-L 748,337 differentially labels human and rat beta(3)-adrenoceptors
2013
As no suitable radioligand exists for the detection of β3-adrenoceptors, we have explored the radioligand binding properties of a tritiated version of the selective β3-adrenoceptor antagonist L 748,337. Kinetic and equilibrium saturation and competition binding experiments were performed with [(3)H]-L 748,337 on membrane fractions of HEK and CHO cells stably transfected with human and rat β-adrenoceptor subtypes. Based on both association/dissociation kinetic and equilibrium saturation binding studies in transfected HEK cells, [(3)H]-L 748,337 exhibited an affinity of approximately 2 nM for human β3-adrenoceptors. Competition studies with agonists and subtype-selective antagonists validated…
Synthesis and biological activity of new anti-inflammatory compounds containing the 1,4-benzodioxine and/or pyrrole system
2007
A series of substituted derivatives containing the 1,4-benzodioxine or pyrrole nucleus are described. All the newly synthesized compounds were examined for their in vitro and in vivo anti-inflammatory activity. Several derivatives, including (S)-2, 14 and 17, showed more anti-inflammatory activity in vivo in these assays (rat paw oedema induced by carrageenan) than the known classical anti-inflammatory agent ibuprofen, whereas other compounds like 1 were equipotent to ibuprofen. Compound 17 was the most outstanding derivative because of its remarkable in vivo anti-inflammatory activity. In this paper, we examine and discuss the structure-activity relationships and anti-inflammatory activiti…
Modulation of hippocampal theta oscillations and spatial memory by relaxin-3 neurons of the nucleus incertus.
2009
Hippocampal theta rhythm is thought to underlie learning and memory, and it is well established that “pacemaker” neurons in medial septum (MS) modulate theta activity. Recent studies in the rat demonstrated that brainstem-generated theta rhythm occurs through a multisynaptic pathway via the nucleus incertus (NI), which is the primary source of the neuropeptide relaxin-3 (RLN3). Therefore, this study examined the possible contribution of RLN3 to MS activity, and associated hippocampal theta activity and spatial memory. In anesthetized and conscious rats, we identified the ability of intraseptal RLN3 signaling to modulate neuronal activity in the MS and hippocampus and promote hippocampal the…
Distribution and targets of the relaxin-3 innervation of the septal area in the rat.
2012
Neural tracing studies have revealed that the rat medial and lateral septum are targeted by ascending projections from the nucleus incertus, a population of tegmental GABA neurons. These neurons express the relaxin-family peptide, relaxin-3, and pharmacological modulation of relaxin-3 receptors in medial septum alters hippocampal theta rhythm and spatial memory. In an effort to better understand the basis of these interactions, we have characterized the distribution of relaxin-3 fibers/terminals in relation to different septal neuron populations identified using established protein markers. Dense relaxin-3 fiber plexuses were observed in regions of medial septum containing hippocampal-proje…