Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen

Background: Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague-Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM.Methods: Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm3) and the proportions of each tumor that were alive, necrotic or degenerative (mm2). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers.Results: Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment.Conclusions: Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors. © 2013 Dias et al.; licensee BioMed Central Ltd.

Evaluation of estrogenic, antiestrogenic and genotoxic activity of nemorosone, the major compound found in brown Cuban propolis

Background: Brown propolis is the major type of propolis found in Cuba; its principal component is nemorosone, the major constituent of Clusia rosea floral resins. Nemorosone has received increasing attention due to its strong in vitro anti-cancer action. The citotoxicity of nemorosone in several human cancer cell lines has been reported and correlated to the direct action it has on the estrogen receptor (ER). Breast cancer can be treated with agents that target estrogen-mediated signaling, such as antiestrogens. Phytoestrogen can mimic or modulate the actions of endogenous estrogens and the treatment of breast cancer with phytoestrogens may be a valid strategy, since they have shown anti-cancer activity.Methods: The aim of the present investigation was to assess the capacity of nemorosone to interact with ERs, by Recombinant Yeast Assay (RYA) and E-screen assays, and to determine by comet assay, if the compound causes DNA-damaging in tumoral and non-tumoral breast cells.Results: Nemorosone did not present estrogenic activity, however, it inhibited the 17-β-estradiol (E2) action when either of both methods was used, showing their antiestrogenicity. The DNA damage induced by the benzophenone in cancer and normal breast cells presented negative results.Conclusion: These findings suggest that nemorosone may have therapeutic application in the treatment of breast cancer. © 2013 Camargo et al.; licensee BioMed Central Ltd.

Evaluation of sample preparation procedures and krypton as an interference standard probe for arsenic speciation by HPLC-ICP-QMS

Different conditions of extraction using water, a methanol-water mixture and nitric acid solutions were evaluated for speciation of As(iii), As(v), DMA and MMA in plant samples that previously received As(v) after being sown and emergence was investigated. Microwave-assisted extraction (MAE) using diluted nitric acid solutions was also performed for arsenic extraction from chicken feed samples. The separation and determination of arsenic species were performed using HPLC-ICP-MS. The interference standard method (IFS) using 83Kr+ as the IFS probe was employed to minimize spectral interferences caused by polyatomic species, such as 40Ar 35Cl+. The extraction procedures tested presented adequate extraction efficiencies (90%), and the four arsenic species evaluated were found in plant samples. Extractions with diluted nitric acid solution at 90 °C were the most efficient strategy, with quantitative recoveries for all four As species in plant tissues. On the other hand, the methanol-water mixture was the solvent with the lowest extraction efficiency (50-60%). For chicken feed samples, MAE at 100 °C for 30 min resulted in an extraction efficiency of 97% and only As(v) was found, without any species interconversion. The IFS method contributed to improving precision and limits of detection and quantification for all tested extraction procedures. Significant improvements on accuracy were obtained by applying the IFS method and recoveries between 77 and 94%, and 82 and 93% were obtained for plant extracts and chicken feed samples, respectively. This journal is © 2013 The Royal Society of Chemistry.

Eficácia de extratovegetais em nematódeos parasitas: avaliação invitro em Haemonchus contortud e avaliação in vitro em Strongyloides venezuelensis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise multielementar da mucosa gástrica de roedores tratados com Alchornea glandulosa, Davilla elliptica e Davilla nitida pela técnica de fluorescência de raios-x por reflexão total

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do extrato aquoso de Casearia sylvestris sobre a neutralização e regeneração da mionecrose induzida pelo veneno da Bothrops jaracussu em camundongos: estudo morfológico e funcional

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Prospecção química e avaliação das atividades e alelopática de Myrcia bella Cambess

Pós-graduação em Ciências Biológicas (Botânica) - IBB

Potencial de atividade antimicrobiana in vitro de extratos vegetais do cerrado frente estirpes de Staphylococcus aureus

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determinação da atividade anti Mycobacterium tuberculosis de metabólitos bioativos de fungos endofíticos empregando a técnica do MABA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação in vitro da atividade antimicrobiana de associações de extratos de Araçá (Psidium cattleianum) e hidróxido de cálcio frente a biofilme multiespécie de Enterococcus faecalis e Candida albicans

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da resposta tecidual dos extratos vegetal aquoso e hidroalcoólico de Aroeira (Astronium urundeuva) pela análise edemogênica e histopatológica em rato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da resposta tecidual dos extratos vegetais aquoso e hidroalcoólico de araçá (Psidium cattleianum) pela análise edemogênica e morfológica em ratos

Pós-graduação em Ciência Odontólogica - FOA

Influência do extrato de araçá (Psidium cattleianum) e aroeira do sertão (Myracrodruon urundeuva) na prevenção à cárie em modelos animais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Atividade antimicrobiana in vitro de extratos hidroetanólicos de Astronium sp incorporados ou não em sistemas nanoestruturados

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação in vitro da atividade antibacteriana de extratos de Byrsonima ssp E Alchornea ssp: estudo comparativo entre as técnicas de diluição em tubos e microplacas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)