Effects of consequenses on patterns of interlocked contingencies; A replication of a metacontingency experiment

The concept of metacontingency was taught to undergraduate students of Psychology by using a "game" simulation proposed originally by Vichi, Andery and Glenn (2009). Twenty-five students, distributed into three groups were exposed to six experimental sessions in which they had to make bets and divide the amounts gained. The three groups competed against each other for photocopies quotas. Two contingencies shifted over the sessions. Under Contingency B, the group would win points only if in the previous round each member had received the same amount of points and under Contingency A, winning was contingent on an unequal distribution of the points. We observed that proportional divisions predominated independent of the contingency in course. The manipulation of cultural consequences (winning or losing points) produced consistent modifications in two response categories: 1) choices of the value bet in each round, and 2) divisions of the points among group members. Controlling relations between cultural consequences and the behavior of dividing were statistically significant in one of the groups, whereas in the other two groups controlling relations were observed only in Contingency B. A review of the reinforcement criteria used in the original experiment is suggested

In Vitro Schistosomicidal Activity of Some Brazilian Cerrado Species and Their Isolated Compounds

Miconia langsdorffii Cogn. (Melastomataceae), Roupala montana Aubl. (Proteaceae), Struthanthus syringifolius (Mart.) (Loranthaceae), and Schefflera vinosa (Cham. & Schltdl.) Frodin (Araliaceae) are plant species from the Brazilian Cerrado whose schistosomicidal potential has not yet been described. The crude extracts, fractions, the triterpenes betulin, oleanolic acid, ursolic acid and the flavonoids quercetin 3-O-beta-D-rhamnoside, quercetin 3-O-beta-D-glucoside, quercetin 3-O-beta-D-glucopyranosyl-(1-2)-alpha-L-rhamnopyranoside and isorhamnetin 3-O-beta-D-glucopyranosyl-(1-2)-alpha-L-rhamnopyranoside were evaluated in vitro against Schistosoma mansoni adult worms and the bioactive n-hexane fractions of the mentioned species were also analyzed by GC-MS. Betulin was able to cause worm death percentage values of 25% after 120 h (at 100 mu M), and 25% and 50% after 24 and 120 h (at 200 mu M), respectively; besides the flavonoid quercetin 3-O-beta-D-rhamnoside promoted 25% of death of the parasites at 100 mu M. Farther the flavonoids quercetin 3-O-beta-D-glucoside and quercetin 3-O-beta-D-rhamnoside at 100 mu M exhibited significantly reduction in motor activity, 75% and 87.5%, respectively. Biological results indicated that crude extracts of R. montana, S. vinosa, and M. langsdorffii and some n-hexane and EtOAc fractions of this species were able to induce worm death to some extent. The results suggest that lupane-type triterpenes and flavonoid monoglycosides should be considered for further antiparasites studies.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2006/60132-4, 2008/01268-9, 2009/00604-8]Coordenadoria de Aperfeicoamento de Pessoal do Ensino Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

Complete screening for glucocerebrosidase mutations in Parkinson disease patients from Portugal

Mutations in the gene encoding beta-glucocerebrosidase, a lysosomal degrading enzyme, have recently been associated with the development of Parkinson disease.http://www.sciencedirect.com/science/article/B6T09-4RDB8NT-4/1/f950a1008e7a0869f9c1b72f485255a

Enantiomeric resolution of (+/-)-licarin A by high-performance liquid-chromatography using a chiral stationary phase

(+/-)-Licarin A (1), a neolignan obtained by the oxidative coupling reaction of isoeugenol, had in this study its enantiomers resolved. A novel, quick and efficient enantiomeric resolution of 1 was directly performed by chiral high-performance liquid chromatography (HPLC-PDA) protocol (CHIRALPACK (R) AD column; 9:1 (v/v) n-hexane:2-propanol; 1.0 mL/min). This method provided a chromatogram profile with a well-resolved peak separation. After isolation of each enantiomer with ee >99.9%, they were analysed in a polarimeter. Compound 2, which showed a retention time (t(r)) of 12.13 min, was the (+)-enantiomer and compound 3 (t(r) =18.90 min) was the (-)-enantiomer. (C) 2011 Elsevier B.V. All rights reserved.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[06/06267-5]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[1998/14956-7]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[2009/15207-4]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[2009/05049-2]Coordenadoria de Aperfeicoamento de Pessoal do Ensino Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

Anti-snake venom activities of extracts and fractions from callus cultures of Sapindus saponaria

Context: Sapindus saponaria L. (Sapindaceae) bark, root, and fruits are used as sedatives and to treat gastric ulcer and also demonstrate diuretic and expectorant effects. Objective: The anti-snake venom properties of callus of S. saponaria are investigated here for the first time. Materials and methods: In vitro cultivated callus of Sapindus saponaria were lyophilized, and the extracts were prepared with different solvents, before submitting to phytochemical studies and evaluation of the anti-ophidian activity. Crude extracts were fractionated by liquid-liquid partition and the fractions were monitored by thin layer chromatography (TLC). Subsequently, anti-ophidian activities were analyzed toward Bothrops jararacussu Lacerda (Viperidae), B. moojeni Hoge (Viperidae), B. alternates Dumeril (Viperidea) and Crotalus durissus terrificus Lineu (Viperidae) venoms and isolated myotoxins and phospholipase A(2) (PLA(2)). Results: Fractions A1, A2 and the extract in MeOH:H2O (9:1) significantly inhibited the toxic and pharmacological activities induced by snake venoms and toxins, when compared to other extracts and fractions. The lethal, clotting, phospholipase, edema-inducing, hemorrhagic and myotoxic activities were partially inhibited by the different extracts and fractions. TLC profiles of the crude extracts (B and C) and fractions (A1 and A2) showed beta-sitosterol and stigmasterol as their main compounds. Stigmasterol exhibited inhibitory effects on enzymatic and myotoxic activities of PLA(2). Discussion and conclusion: Sapindus saponaria extracts and fractions presented anti-ophidian activity and could be used as an adjuvant to serum therapy or for its supplementation, and in addition, as a rich source of potential inhibitors of enzymes involved in several pathophysiological human and animal diseases.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Universidade de Ribeirao Preto UNAERPUniversidade de Ribeirao Preto UNAERPFaculdade de Ciencias Farmaceuticas de Ribeirao PretoUSPFaculdade de Ciencias Farmaceuticas de Ribeirao Preto-US

Trypanosoma cruzi: evaluation of (-)-cubebin derivatives activity in the messenger RNAs processing

No fully effective treatment has been developed since the discovery of Chagas` disease. Since drug-resistant Trypanosoma cruzi strains are occurring and the current therapy is effective in the acute phase but with various adverse side effects, more studies are needed to characterize the susceptibility of T. cruzi to new drugs. Pre-mRNA maturation in trypanosomatids occurs through a process called trans-splicing, which is unusual RNA processing reaction, and it implies the processing of polycistronic transcription units into individual mRNAs; a short transcript spliced leader (SL RNA) is trans-spliced to the acceptor pre-mRNA, giving origin to the mature mRNA. Cubebin derivatives seem to provide treatments with less collateral effects than benznidazole and showed similar or better trypanocidal activities than benznidazole. Therefore, the cubebin derivatives ((-)-6,6`-dinitrohinokinin (DNH) and (-)-hinokinin (HQ)) interference in the mRNA processing was evaluated using T. cruzi permeable cells (Y and BOL (Bolivia) strains) following by RNase protection reaction. These substances seem to intervene in any step of the RNA transcription, promoting alterations in the RNA synthesis, even though the RNA processing mechanism still occurs. Furthermore, HQ presented better activity against the parasites than DNH, meaning that BOL strain seems to be more resistant than Y.PADC/FCF-UNESP (Programa de Apoio ao Desenvolvimento Cientifico/Faculdade de Ciencias Farmaceuticas Unesp)FUNDUNESP (Fundacao para o Desenvolvimento-Unesp-Desenvolvimento e Tecnologia)PIBIC/CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico)FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo

Schistosomicidal evaluation of flavonoids from two species of Styrax against Schistosoma mansoni adult worms

Context: Schistosomiasis is a major health problem worldwide. Thus, the search for new schistosomicidal agents from natural sources can provide prototypes for drug discovery. Objective: The present study investigated the chemical composition of the EtOAc fractions of Styrax pohlii Pohl (Styracaceae) (EF-SP) aerial parts and S. camporum A. DC. leaves (EF-SC), as well as schistosomicidal activities against Schistosoma mansoni adult worms, which have not yet been studied. Materials and methods: The crude ethanol extracts of S. camporum leaves and S. pohlii aerial parts (EE-SC and EE-SP) were partitioned with n-hexane, EtOAc, and n-BuOH. The EtOAc fractions were purified by preparative HPLC. The crude extracts, EtOAc fractions and pure compounds were tested against S. mansoni adult worms in vitro. Results: The purification procedure resulted in the isolation of kaempferol-3-O-(2 '',4 ''-di-O-(E)-p-coumaroyl)-beta-D-glucopyranoside (1), kaempferol-3-O-(2 '',6 ''-di-O-(E)-p-coumaroyl)-beta-D-glucopyranoside (2), quercetin (3), and kaempferol (4). The bioassay results indicated that EE-SC, EF-SC, EF-SP, and compounds 2 and 4 are able to separate coupled S. mansoni adult worms. Additionally, EE-SC, EF-SP, and compound 4 killed the adult schistosomes in vitro at 100 mu g/mL and 100 mu M. Discussion and conclusion: This is the first time that the presence of compounds 1-2 in S. pohlii and 3-4 in S. camporum has been reported. Additionally, biological results indicated that S. pohlii and S. camporum have great potential as a source of active compounds.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2008/10.283-1]Coordenadoria de Aperfeicoamento de Pessoal do Ensino Superior (CAPES)Coordenadoria de Aperfeicoamento de Pessoal do Ensino Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

Síntese, atividade antimicrobiana e estudo in silico de 1,2,4-oxadiazóis derivados do levulinato de etila

This study analyzes the antileishmanial activity of the crude ethanol extract, fractions, and isolated compounds of A. othonianum nuts. Antileishmanial activity was evaluated against Leishmania amazonensis promastigotes in vitro. The phytochemical study was performed by high-performance liquid chromatography-high-resolution mass spectrometry-diode array detector (HPLC-HRMS-DAD) and by preparative HPLC. HPLC-HRMS-DAD analysis of the bioactive extract confirmed the presence of ten alkyl phenol derivatives that had previously been isolated from A. occidentale. Bioassay-guided isolation afforded cardanol triene, cardanol diene, cardanol monoene, cardol triene, anacardic acid triene, anacardic acid diene, and anacardic acid monoene. Cardol triene gave an IC50 of 80.66 µM. The obtained data suggest that the evaluated extract, fractions, and cardol triene had moderate activity against L. amazonensis promastigotes. This is the first description of alkyl phenols in A. othonianum.Este estudo visou avaliar a atividade antileishmanial do extrato bruto etanólico, frações e substâncias isoladas obtidos das castanhas de A. othonianum. A atividade antileishmania foi avaliada por ensaio in vitro nas formas promastigotas de Leishmania amazonensis. O estudo fitoquímico foi realizado por cromatografia líquida de alta eficiência - espectrometria de massa de alta resolução - detector de arranjo de diodos (CLAE-EMAR-DAD) e por CLAE-preparativa. A análise por CLAE-EMAR-DAD do extrato bioativo confirmou a presença de dez derivados de alquil-fenóis previamente isolados de A. occidentale.  A investigação bioguiada resultou no isolamento do cardanol trieno, cardanol dieno, cardanol monoeno, cardol trieno, ácido anacárdico trieno, ácido anacárico dieno e ácido anacárico monoeno. O cardol trieno apresentou uma CI50 de 80,66 µM. Os dados obtidos sugeriram que o extrato, frações e o cardol trieno possuem atividade moderada no ensaio nas formas promastigotas de L. amazonensis. Este é o primeiro relato de alquil-fenóis em A. othonianum