Phenolic derivatives from Baccharis retusa DC. (Asteraceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-09972270 São Paulo, BrazilUniv Presbiteriana Mackenzie, Ctr Ciencias & Humanidades, BR-01302907 São Paulo, BrazilUniv Presbiteriana Mackenzie, Ctr Ciencias Biol & Saude, BR-01302907 São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-09972270 São Paulo, BrazilWeb of Scienc

Calein C, a Sesquiterpene Lactone Isolated From Calea Pinnatifida (Asteraceae), Inhibits Mitotic Progression and Induces Apoptosis in MCF-7 Cells

Breast cancer is the most common cancer in women worldwide. Estrogen receptor-positive (ER+) breast cancer represents approximately 75% of diagnosed cases, while 15–20% of them are triple-negative (TN). Although there have been improvements in the therapeutic approach, the mortality rate remains elevated. Thus, it is necessary to identify new chemotherapeutic agents. The present study aimed to evaluate the effects of calein C, a sesquiterpene lactone isolated from Calea pinnatifida, on breast cancer cell lines MCF-7 (ER+), Hs578T (TN) and MDA-MB-231 (TN). Calein C significantly reduced the viability of all cell lines; however, MCF-7 cells were more responsive than MDA-MB-231 or Hs578T cells. Thus, the MCF-7 cell line was selected for further investigation. We demonstrated that calein C inhibited cell cycle progression in MCF-7 cells at M-phase. Increased frequency of mitosis was observed in calein C-treated samples compared to the control group, especially of the cell population in initial stages of the mitosis. These events were associated with the ability of calein C to modulate expression levels of critical regulators of mitosis progression. We observed a significant reduction in the relative mRNA abundance of PLK1 and AURKB along with a concomitant increase in CDKN1A (p21) in treated samples. In addition, calein C induced apoptosis in MCF-7 cells due to, at least in part, its ability to reduce the BCL2/BAX ratio. Therefore, our data provide evidence that calein C is an important antimitotic agent and should be considered for further in vivo investigations

Self-Organizing Maps of Molecular Descriptors for Sesquiterpene Lactones and Their Application to the Chemotaxonomy of the Asteraceae Family

The Asteraceae, one of the largest families among angiosperms, is chemically characterised by the production of sesquiterpene lactones (SLs). A total of 1,111 SLs, which were extracted from 658 species, 161 genera, 63 subtribes and 15 tribes of Asteraceae, were represented and registered in two dimensions in the SISTEMATX, an in-house software system, and were associated with their botanical sources. The respective 11 block of descriptors: Constitutional, Functional groups, BCUT, Atom-centred, 2D autocorrelations, Topological, Geometrical, RDF, 3D-MoRSE, GETAWAY and WHIM were used as input data to separate the botanical occurrences through self-organising maps. Maps that were generated with each descriptor divided the Asteraceae tribes, with total index values between 66.7% and 83.6%. The analysis of the results shows evident similarities among the Heliantheae, Helenieae and Eupatorieae tribes as well as between the Anthemideae and Inuleae tribes. Those observations are in agreement with systematic classifications that were proposed by Bremer, which use mainly morphological and molecular data, therefore chemical markers partially corroborate with these classifications. The results demonstrate that the atom-centred and RDF descriptors can be used as a tool for taxonomic classification in low hierarchical levels, such as tribes. Descriptors obtained through fragments or by the two-dimensional representation of the SL structures were sufficient to obtain significant results, and better results were not achieved by using descriptors derived from three-dimensional representations of SLs. Such models based on physico-chemical properties can project new design SLs, similar structures from literature or even unreported structures in two-dimensional chemical space. Therefore, the generated SOMs can predict the most probable tribe where a biologically active molecule can be found according Bremer classification.CNPqCNPqUEPBUEP

In vitro antileishmanial and antitrypanosomal activities of flavanones from Baccharis retusa DC. (Asteraceae)

Leishmaniasis and Chagas' are parasitic protozoan diseases that affect the poorest population in the world, causing a high mortality and morbidity. As a result of highly toxic and long-term treatments, novel, safe and more efficacious drugs are essential. in this work, the CH2Cl2 phase from MeOH extract from the leaves of Baccharis retusa DC. (Asteraceae) was fractioned to afford two flavonoids: naringenin (1) and sakuranetin (2). These compounds were in vitro tested against Leishmania spp. promastigotes and amastigotes and Ttypanosoma cruzi trypomastigotes and amastigotes. Compound 2 presented activity against Leishmania (L) amazonensis, Leishmania (V.) braziliensis, Leishmania (L) major, and Leishmania (L) chagasi with IC50 values in the range between 43 and 52 mu g/mL and against T. cruzi trypomastigotes (IC50= 20.17 mu g/mL). Despite of the chemical similarity, compound 1 did not show antiparasitic activity. Additionally, compound 2 was subjected to a methylation procedure to give sakuranetin-4'-methyl ether (3), which resulted in an inactive compound against both Leishmania spp. and T. cnizi. the obtained results indicated that the presence of one hydroxyl group at C-4' associated to one methoxyl group at C-7 is important to the antiparasitic activity. Further drug design studies aiming derivatives could be a promising tool for the development of new therapeutic agents for Leishmaniasis and Chagas' disease. (C) 2011 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Pesquisa e DesenvolvimentoUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Diadema, SP, BrazilInst Adolfo Lutz Registro, Dept Parasitol, São Paulo, BrazilUniv Fed ABC, Ctr Ciencias Nat & Humanas, Santo Andre, SP, BrazilUniv Presbiteriana Mackenzie, Ctr Ciencias & Humanidades, São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Diadema, SP, BrazilFAPESP: 06/57626-5FAPESP: 08/11496-9Conselho Nacional de Pesquisa e Desenvolvimento: 473405/2008-3Conselho Nacional de Pesquisa e Desenvolvimento: 477422/2009-8Web of Scienc

Quasi-stationary simulations of the directed percolation universality class in d = 3 dimensions

We present quasi-stationary simulations of three-dimensional models with a single absorbing configuration, namely the contact process (CP), the susceptible-infected-susceptible (SIS) model and the contact replication process (CRP). The moment ratios of the order parameters for the DP class in three dimensions were set up using the well established SIS and CP models. We also show that the mean-field exponent for d = 3 reported previously for the CRP (Ferreira 2005 Phys. Rev. E 71 017104) is a transient observed in the spreading analysis

Os olhares de futuros professores sobre a metodologia de trabalho de projeto

Tendo feito a formação de futuros professores do 1º ciclo do ensino básico na metodologia de trabalho de projeto, foi nossa intenção recolher as opiniões deles sobre a utilização dessa metodologia na educação escolar. Os resultados obtidos mostram que os futuros professores compreenderam o conceito e a prática da metodologia de trabalho de projeto, com opiniões próximas daqueles descritos teoricamente, referindo várias vantagens na sua utilização no processo de ensino e de aprendizagem. Por esta razão, são, também, da opinião que é importante a formação de professores nessa metodologia de ensino e de aprendizagem

Characterization of macrofauna associated with articulated calcareous algae (Corallinaceae, rhodophyta) occurring in a hydrodynamic gradient on the espírito santo state coast, brazil

The aims of this study were to characterize the macrofauna associated with the articulated calcareous algae occurring on a hydrodynamic gradient off the Vitória metropolitan area, Espírito Santo State, Brazil, and to describe its temporal distribution. Physicochemical variables were measured in situ, and samples of sediment, water and phytal were taken from three sites along the coast in August and November 2005 (winter and spring, respectively) and in February and May 2006 (summer and fall, respectively). Twenty random samples were taken from the rocky surface in the lower midlittoral zone at each site, each season. Six species of articulated algae harboring 9,651 animal specimens distributed among 189 taxa were collected. The dominant taxonomic groups were Mollusca, Polychaeta and Crustacea. The main patterns revealed by statistical analysis related to differences in the abundance and richness at the sample sites, as well as to the correlation between the physicochemical variables and community distance matrices, indicating the importance of the physicochemical variables in the differentiation of the communities. Results also indicated that the variable which most influenced the physicochemical and community properties was the hydrodynamic character of the sites: a high level of hydrodynamism resulting in the calcareous algae´s sheltering a lower abundance and diversity of animal species than a lower level one.Os objetivos deste estudo foram caracterizar a macrofauna associada às algas calcárias articuladas num gradiente de hidrodinamismo no litoral da região metropolitana de Vitória, Espírito Santo, Brasil, e descrever a distribuição temporal. Variáveis fisicoquímicas foram medidas in situ, e amostras do sedimento, água e fital foram feitas em três pontos amostrais do litoral em agosto e novembro de 2005 (inverno e primavera, respectivamente) e fevereiro e maio de 2006 (verão e outono, respectivamente). Em cada ponto, e por estação do ano, foram obtidas 20 amostras aleatórias da superfície do costão rochoso na região do mediolitoral inferior. Seis espécies de algas calcárias articuladas foram coletadas e abrigaram 9.651 espécimes animais distribuídos em 189 táxons. Os grupos taxonômicos dominantes foram Mollusca, Polychaeta e Crustacea. Os principais padrões revelados pelas análises estatísticas foram diferenças na abundância e riqueza entre os pontos amostrais e correlação entre as variáveis fisicoquímicas e a comunidade, indicando que os parâmetros fisicoquímicos foram importantes para a caracterização destas. Os resultados indicaram ainda que a variável que mais influenciou as propriedades fisicoquímicas e da comunidade foi o grau de hidrodinamismo: locais com hidrodinamismo elevado permitem que algas calcárias abriguem uma menor abundância e diversidade de espécies animais do que locais com hidrodinamismo elevado

Testing synchrotron models and frequency resolution in BINGO 21 cm simulated maps using GNILC

To recover the 21 cm hydrogen line, it is essential to separate the cosmological signal from the much stronger foreground contributions at radio frequencies. The BINGO radio telescope is designed to measure the 21 cm line and detect BAOs using the intensity mapping technique. This work analyses the performance of the GNILC method, combined with a power spectrum debiasing procedure. The method was applied to a simulated BINGO mission, building upon previous work from the collaboration. It compares two different synchrotron emission models and different instrumental configurations, in addition to the combination with ancillary data to optimize both the foreground removal and recovery of the 21 cm signal across the full BINGO frequency band, as well as to determine an optimal number of frequency bands for the signal recovery. We have produced foreground emissions maps using the Planck Sky Model, the cosmological Hi emission maps are generated using the FLASK package and thermal noise maps are created according to the instrumental setup. We apply the GNILC method to the simulated sky maps to separate the Hi plus thermal noise contribution and, through a debiasing procedure, recover an estimate of the noiseless 21 cm power spectrum. We found a near optimal reconstruction of the Hi signal using a 80 bins configuration, which resulted in a power spectrum reconstruction average error over all frequencies of 3%. Furthermore, our tests showed that GNILC is robust against different synchrotron emission models. Finally, adding an extra channel with CBASS foregrounds information, we reduced the estimation error of the 21 cm signal. The optimisation of our previous work, producing a configuration with an optimal number of channels for binning the data, impacts greatly the decisions regarding BINGO hardware configuration before commissioning.Comment: Submitted to A&