1,721,012 research outputs found
N-Homolupinanoyl and N-(ω-lupinylthio)alkanoyl derivatives of some tricyclic systems as ligands for muscarinic M1 and M2 receptor subtypes
No full textA set of N-homolupinanoyl- and N-(v-lupinylthio)alkanoyl derivatives of tricyclic systems (as phenothiazine, iminodibenzyl and
dihydropyridobenzodiazepinone) has been prepared and tested for affinity for rat muscarinic M1 and M2 receptor subtypes labeled
with [3H]pirenzepine and [3H]AF-DX 384. Good affinity for both M1 and M2 subtypes was displayed by most compounds, often
with nanomolar Ki values, which for lupinylthiopropionyl- and lupinylthiobutyryl-phenothiazines (13/16) were comparable to
those of pirenzepine and methoctramine, respectively. However, only moderate selectivity for one or the other subtype was seen
Synthesis and biological investigation of 2-(tetrahydropyran-2'-yl) and 2-(tetrahydrofuran-2'-yl)-benzimidazoles
No full textEffect of some quinolizidine derivatives on the release of serotonin, noradrenaline, dopamine and acetylcholine from rat brain synaptosomes
No full textAnethole dithiolethione lowers the homocysteine and raises the glutathione levels in solid tissues and plasma of rats: a novel non-vitamin homocysteine-lowring agent..
No full textHigh homocysteine (Hcys) levels are suspected to contribute to the pathogenesis of cardiovascular disease and of other chronic conditions. Failure of B vitamins to reduce the incidence of cardiovascular events while lowering the Hcys levels, has prompted the search for alternative treatments. We tested the ability of anethole dithiolethione (ADT) to lower the Hcys levels in rats and we explored possible underlying mechanisms. Parenteral administration of 10mg/kg ADT to normal rats for 3 days lowered the Hcys levels between 51.4% and 31.5% in kidneys, liver, testis and plasma. Concomitantly, glutathione (GSH) increased between 112% and 28% in kidneys, brain, liver and plasma whereas protein thiolation index decreased 30%. In hyperhomocysteinemic rats, the plasma Hcys levels dropped 70% following a single ip injection of 10mg/kg ADT, while they decreased 55% following oral administration of 2mg/kg/day ADT for one week. Significant additive effects occurred when sub-therapeutic doses of ADT and folic acid were used in combination. To test the possible mechanism(s) of these actions, we perfused isolated rat livers and kidneys with albumin-bound Hcys, the prevalent form of plasma Hcys, and physiological thiols and disulfides at different ratios. In both organ preparations, the elimination rate of albumin-bound Hcys was progressively faster as the amount of reduced thiols was increased in the perfusate. These findings indicate that ADT shifts the redox ratio of GSH and other thiols with their oxidized forms toward the reduced forms, thus favoring the dissociation of albumin-bound Hcys and its transfer to renal and hepatic cells for further processing
Pharmacological activity of 1-lupinylquinoxalin-2(1H)-ones 3,6-disubstituted [ATTIVITA FARMACOLOGICA DI 1-LUPINILCHINOSSALIN-2(1H)-ONI 3,6-DISOSTITUITI]
No full textFive 1-lupinyl-3R'-6R"-quinoxalin-2(1H)-ones were tested in mice for acute toxicity, explorative activity inhibition, analgesic activity and for antagonism against physostigmine, strychnine and pentylentetrazol (cardiazol). As reference compounds were used chloropromazine, morphine, atropine and diazepam respectively. All tested compounds inhibit the explorative activity and exhibit high analgesic activity. Compound (I) protects completely the animals from physostigmine toxicity, while compound (IV) antagonizes, although only slightly, all the toxicants tested
Epimerization of lupinine to epilupinine and vice versa. Reexamination of the structures of lupinal and epilupinal
No full textThough the epimerization of lupinine has been largely investigated, a not previously observed compound of formula C10H17NO has been now isolated from the mixture of alkaloids that remains after the separation of epi-lupinine. It is insoluble in dry ether, but it is soluble in ethanol, from which is recovered as an ether soluble oil that slowly returns to the ether insoluble solid form. For these characteristics and on the base of GC-MS, 1H-NMR and IR spectra, it is considered as the internal salt of the common enolic form of lupinal and epi-lupinal, with which it is in equilibrium when standing in solution. The oily form, but not the solid one, is able to improve the conversion of lupinine to epi-lupinine, proving the role of the aldehydes in the epimerization process. It was observed that also epi-lupinine can be converted to lupinine. Finally, the solid lupinal described by Zaboev should be considered coincident with the now isolated enol internal salt, while the oily epi-lupinal of Wicky and Schumann is indeed a mixture of epi-lupinal with a minor amount of lupinal, that on standing is converted to the internal salt of the common enolic form
Quinolizidinyl derivatives of 5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepin-6-one as ligands for muscarinic receptors
No full textQuinolizidinyl derivatives of the tricyclic systems characterizing pirenzepine and nuvenzepine,
were prepared and tested as ligands for muscarinic M1, M2 and M3 receptors; 5,11-dihydro-11-[(S-lupinyl)-
thioacetyl]-6H-pyrido[2,3-b][1,4]benzodiazepin-6-one exhibited IC50 = 10 nM for M1 and 760 nM for both M2
and M3 subtypes. During the synthesis some interesting side compounds were isolated and characterized
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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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