Publications

The cytotoxicity of three extracts (petroleum ether, ethyl acetate and n-butanol) from a plant used in folk medicine, Marchantia convoluta, to human non-small cell lung carcinoma (H1299) and liver carcinoma (HepG2) cell lines was tested. After 72-h incubation of lung and liver cancer cell cultures with varying concentrations of extracts (15 to 200 microg/mL), cytotoxicity was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and reported in terms of cell viability. The extracts that showed a significant cytotoxicity were subjected to gas chromatography-mass spectrometry analysis to identify the components. The ethyl acetate, but not the petroleum ether or n-butanol extract, had a significant cytotoxicity against lung and liver carcinoma cells with IC50 values of 100 and 30 microg/mL, respectively. A high concentration of ethyl acetate extract (100 microg/mL) rapidly reduced the number of H1299 cells. At lower concentrations of ethyl acetate extract (15, 30, and 40 microg/mL), the numbers of HepG2 cells started to decrease markedly. Gas chromatography-mass spectrometry analysis of the ethyl acetate extract revealed the presence of several compounds such as phytol (23.42%), 1,2,4-tripropylbenzene (13.09%), 9-cedranone (12.75%), ledene oxide (7.22%), caryophyllene (1.82%), and caryophyllene oxide (1.15%). HPLC analysis result showed that there were no flavonoids in ethyl acetate extract, but flavonoids are abundant in n-butanol extract. Further studies are needed regarding the identification, toxicity, and mechanism of action of active compounds.

The effects of mercury (Hg) concentrations ranging from 0 (control) to 1024 µg 1-1 upon embryogenesis, survival, growth and metamorphosis of Crassostrea gigas (Thunberg) oyster larvae were investigated. Embryogenesis was abnormal in 50 % of the individuals at 11 µg 1-1 . The 48 h LD50 for D·shaped, umbonate and pediveliger larvae were 33, 115 and 200 µg 1-1 respectively. The increase in LD50 was partially explained by the larval weight increase, although weight-specific tolerance to Hg was higher in smaller larvae. Growth, the most sensitive physiological process studied, was significantly retarded at 4 µg 1-1. The metamorphosis rate was significantly reduced when competent pediveligers were exposed to 64 µg 1-1 for 48 h prior to the addition of the metamorphosis inducer epinephrine. The implications of the present results for monitoring pollution by utilising different bivalve larval stages are discussed.

O presente estudo tem como objetivo a aplicação de três modelos de localização de hotéis em destinos urbanos: o modelo de cidade histórico-turística de Burtenshaw, Bateman e Ashworth (Burtenshaw et al., 1981), o modelo de cidade turístico-histórica de Ashworth e Tunbridge (2000) e o modelo de hierarquia da localização de hotéis de Egan e Nield (2000). O objeto de estudo foi a hotelaria da cidade de Curitiba durante o período de 1966 a 2008. A aplicação de modelos europeus em uma cidade brasileira deve-se primeiramente à inexistência de modelos brasileiros e a busca de um modelo de localização de hotéis. Adotou-se uma abordagem metodológica empírico-analítica e revisão de literatura conceitual; os dados foram obtidos por meio de pesquisa bibliográfica e documental. Após o estudo verificou-se que houve dispersão na localização dos hotéis após a instalação das montadoras automobilísticas na região metropolitana de Curitiba após o ano de 1995, fato não ocorrido no ano de 1972 quando a Cidade Industrial de Curitiba foi inaugurada. A aplicação do modelo de cidade histórico-turística de Burtenshaw et al. (1981) foi corroborada, os hotéis ficam próximos ao centro histórico e das vias de acesso. O modelo de Ashworth e Tunbridge (2000), não se confirmou em Curitiba, sendo então detectado um modelo de cidade turístico-histórica diferente. Quanto ao modelo de hierarquia da localização de hotéis de Egan e Nield (2000), foi refutado, pois os hotéis de Curitiba não seguem uma ordem de localização. Não existe uma maior concentração de categoria de hotéis que corrobore o modelo defendido pelos autores o que evidencia a particularidade da localização da hotelaria da capital paranaense.

As of late, polyphenols have increasingly interested the scientific community due to their proposed health benefits. Much of this attention has focused on their bioavailability. Polyphenol–gut microbiota interactions should be considered to understand their biological functions. The dichotomy between the biotransformation of polyphenols into their metabolites by gut microbiota and the modulation of gut microbiota composition by polyphenols contributes to positive health outcomes. Although there are many studies on the in vivo bioavailability of polyphenols, the mutual relationship between polyphenols and gut microbiota is not fully understood. This review focuses on the biotransformation of polyphenols by gut microbiota, modulation of gut microbiota by polyphenols, and the effects of these two-way mutual interactions on polyphenol bioavailability, and ultimately, human health.