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Furoxan Analogues of the Histamine H3 receptor antagonist imoproxifan and related furazan derivatives
No full textThe cyano-NNO-azoxy function in the design of an irreversible label for alpha1-adrenoreceptors
No full textPotential histamine H2-receptor antagonists: synthesis and pharmacological activity of derivatives containing acylaminofurazan moieties
No full textFast gas chromatographic/mass spectrometric determination of diuretics and masking agents in human urine. Development and validation of a productive screening protocol for antidoping analysis
No full textAn analytical procedure was developed for the fast screening of 16 diuretics (acetazolamide, althiazide, amiloride, bendroflumethiazide,
bumetanide, canrenoic acid, chlorthalidone, chlorthiazide, clopamide, ethacrynic acid, furosemide, hydrochlorthiazide, hydroflumethiazide, indapamide, triamterene, trichlormethiazide) and a masking agent (probenecid) in human urine. The whole method involves three analytical steps, including (1) liquid/liquid extraction of the analytes from the matrix, (2) their reaction with methyl iodide at 70 ◦C for 2 h to form methyl derivatives, (3) analysis of the resulting mixture by fast gas chromatography/electron impact mass spectrometry (fast GC/EI-MS). The analytical method was validated by determining selectivity, linearity, accuracy, intra and inter assay precision, extraction efficiencies and signal to noise ratio (S/N) at
the lowest calibration level (LCL) for all candidate analytes. The analytical performances of three extraction procedures and five combination of derivatization parameters were compared in order to probe the conditions for speeding up the sample preparation step. Limits of detection (LOD) were evaluated in both EI-MS and ECNI-MS (electron capture negative ionization mass spectrometry) modes, indicating better sensitivity for most of the analytes using the latter ionization technique. The use of short columns and high carrier gas velocity in fast GC/MS produced efficient separation of the analytes in less than 4 min, resulting in a drastic reduction of the analysis time, while a resolution comparable to that obtained from classic GC conditions is maintained. Fast quadrupole MS electronics allows high scan rates and effective data acquisition both in scan and selected ion monitoring mode
Simultaneous ultrasound-assisted water extraction and β-cyclodextrin encapsulation of polyphenols from Mangifera indica stem bark in counteracting TNFα-induced endothelial dysfunction.
No full textThis study proposes an alternative technique to prevent heat degradation induced by classic procedures of bioactive compound extraction, comparing classical maceration/decoction in hot water of polyphenols from Mango (Mangifera indica L.) (MI) with ultrasound-assisted extraction (UAE) in a water solution of β-cyclodextrin (β-CD) at room temperature and testing their biological activity on TNFα-induced endothelial dysfunction. Both extracts counteracted TNFα effects on EAhy926 cells, down-modulating interleukin-6, interleukin-8, cyclooxygenase-2 and intracellular adhesion molecule-1, while increasing endothelial nitric oxide synthase levels. β-CD extract showed higher efficacy in improving endothelial function. These effects were abolished after pre-treatment with the oestrogen receptor inhibitor ICI1182,780. Moreover, the β-CD extract induced Akt activation and completely abolished the TNFα-induced p38MAPK phosphorylation. UAE and β-CD encapsulation provide an efficient extraction protocol that increases polyphenol bioavailability. Polyphenols from MI play a protective role on endothelial cells and may be further considered as oestrogen-like molecules with vascular protective properties
[3-(1H-imidazol-4-yl)propyl]guanidines containing furoxan moyeties: a new class of H3-agonists endowed with NO-donor properties
No full textSynthesis and pharmacological characterisation of a series of products obtained by coupling the H-3-antagonist SKF 91486 through appropriate spacers with the NO-donor 3-phenylfuroxan-4-yloxy and 3-benzenesulfonylfuroxan-4-yloxy moieties, as well as with the corresponding furazan substructures, devoid of NO-donating properties, are reported. All the products were tested for their H-3-antagonistic and H-2-agonistic properties on electrically-stimulated guinea-pig ileum segments and guinea-pig papillary muscle, respectively. The whole series of compounds displayed good H-3-antagonist behaviour and feeble partial H-2-agonist activity. Among furoxan derivatives, the benzenesulfonyl hybrid 28, a good NO-donor, triggered a dual NO-dependent muscle relaxation and H3-antagonistic effect on guinea-pig intestin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
[3-(1H-Imidazol-4-yl)propyl]guanidines containing furoxan moieties: a New Class of H3-Antagonists endowed with NO-Donor properties
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