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ABSTRACT: The objective of this study was to evaluate the hepatoprotective effect of the honey bee Apis mellifera ethanolic extract of the red propolis, obtained in four municipalities of the Rio Grande do Norte semi-arid region, through an in vitro evaluation of the antineoplastic potential in human hepatic carcinoma (HepG2) and normal cell lines (L929), and from the comet assay in hepatic cell lines (ZF-L hepatocytes) to evaluate the genoprotective potential of the extract. The hepatoprotective effect was also evaluated in vivo by the induction of chronic experimental hepatic lesions in rodents (Rattus norvegicus Berkenhout, 1769), Wistar line, by intraperitoneal administration of thioacetamide (TAA) at the dose of 0.2g/kg. The animals were distributed in the following experimental groups: G1 (control), G2 (treated with 500mg/kg ethanolic extract of propolis), G3 (treated with 500mg/kg of ethanolic extract and TAA) and G4 (treated with TAA). All rats were submitted to serum biochemical, macroscopic, histological and stereological biochemical exams of the liver. It was verified the genoprotective effect of red propolis since the mean damages promoted to DNA in cells tested with the extract were significantly lower than the mean of the positive control damage (hydrogen peroxide). The red propolis extract did not present cytotoxic activity to the tumor cells of human liver cancer, as well as to normal ones. The absence of cytotoxicity in normal cells may indicate safety in the use of the propolis extract. The results of the serum biochemical evaluation showed that the serum levels of the aminotransferase enzymes (AST) did not differ significantly between G1, G2 and G3 when compared to each other. G4 showed significant increase in levels compared to the other groups, indicating that the administration of the extract did not cause liver toxicity, as well as exerted hepatoprotective effect against the hepatic damage induced by TAA. The G3 and G4 animals developed cirrhosis, but in G3 the livers were characterized by the presence of small regenerative nodules and level with the surface of the organ, whereas in G4 the livers showed large regenerative nodules. The livers of the G1 and G2 animals presented normal histological appearance, whereas the livers of the G3 animals showed regenerative nodules surrounded by thin septa of connective tissue, and in G4 the regenerative nodules were surrounded by thick septa fibrous connective tissue. The analysis of the hepatic tissues by means of stereology showed that there was no statistical difference between the percentage of hepatocytes, sinusoids, and collagens in G1 and G2. In G3 the percentage of hepatocytes, sinusoids, and collagen did not differ significantly from the other groups. It was concluded that the ethanolic extract of the red propolis exerted a hepatoprotective effect, because it promoted in vitro reduction of the damage to the DNA of liver cells, antineoplastic activity in human hepatocellular carcinoma cell line (HepG2) and did not exert cytotoxic effect in normal cells or was able to reduce liver enzyme activity and the severity of cirrhosis induced by TAA in vivo.

Resumo: Esse estudo objetivou avaliar a composição química e potencial terapêutico do extrato hidroalcóolico de geoprópolis produzidas por abelhas Plebeia aff. flavocincta no semiárido do Rio Grande do Norte. Oito amostras (A-H) foram submetidas a quantificação dos teores de fenóis e flavonoides totais e avaliação da atividade antioxidante através do método DPPH (2,2-difenil-1-picril-hidrazilo). Além disso, foram investigadas as atividades antibacteriana, através do método de difusão em ágar, e a cicatrizante, através da indução de feridas cirúrgicas experimentais em Rattus norvegicus Berkenhout, 1769, linhagem Wistar, tratados com creme à base de geoprópolis. Duas amostras (F e G) se destacaram por apresentar altos valores de fenóis e flavonoides totais. A capacidade antioxidante acima de 90% foi observada em cinco amostras. Os extratos foram considerados eficazes no que se refere a atividade antibacteriana, pois das oito amostras, cinco promoveram a formação de halos de inibição ≥9mm para todas as cepas testadas. Duas amostras (D e G) se destacaram em relação as demais por apresentar excelentes resultados, uma vez que, promoveram a formação de halos de inibição para as bactérias Staphylococcus epidermidis e Escherichia coli, superiores estatisticamente aos valores dos antibióticos controles, quando na concentração de 100%. As amostras A e G promoveram, respectivamente, a formação de halos de inibição, que não diferiram significativamente dos halos produzidos pelos antibióticos controles em todas as concentrações testadas para E. coli e Staphylococcus aureus. A análise do processo de cicatrização sob os pontos de vista clínico, macroscópico e histológico permitiu concluir, que o uso do creme à base de geoprópolis apresentou influência positiva na cicatrização de feridas cutâneas experimentais, por promover reação inflamatória menos intensa e fechamento mais rápido das feridas em relação ao grupo controle.

Resumo: Este artigo apresenta relatos de sete distintas patologias de origem reprodutiva ainda não descritas em cutias (Dasyprocta aguti Linnaeus, 1758) fêmeas, que afetaram a fertilidade ou resultaram na morte do animal. Descreveu-se a natureza, a localização e a frequência das alterações patológicas macroscópicas e histológicas dos órgãos que compõem o sistema reprodutivo de cutias fêmeas, criadas sob condições de cativeiro no semiárido do Brasil. Foram avaliados através do exame anatomopatológico o aparelho reprodutivo de trinta e nove cutias mortas naturalmente e encaminhadas ao Laboratório de Patologia Veterinária, no período de fevereiro de 2010 a maio de 2015. Destas, constatou-se alterações patológicas no sistema reprodutivo de 10 (25,6 %). No total, 13 alterações foram observadas, sendo que, em alguns animais haviam a coexistência de mais de uma alteração. Assim, as alterações patológicas encontradas foram: endometrite (n=4; 30,8%), piometra (n=3; 23%), retenção de placenta (n=2; 15,4%), maceração fetal (n=1; 7,7%), mumificação fetal (n=1; 7,7%), parto distócico (n=1; 7,7%) e ovários afuncionais (n=1; 7,7%).

Amorphous FeMBCu (M=Nb, Zr) and FeNbSiBCu alloys with nanometer size crystallites have attracted attention due to their soft magnetic properties. The mechanism through which crystallization affects the corrosion and the comparative effect of corrosion on magnetic properties of FeMBCu (M=Nb, Zr) and FeNbSiBCu alloys has not yet been evaluated. In this paper the effect of partial crystallization on corrosion resistance of amorphous Fe73Nb3Si15.5B7.5 Cu1 and Fe80Zr3.5Nb3.5B12Cu1 alloy ribbons and the comparative effect of corrosion on saturation magnetic flux density, Bs, of these alloys were investigated. The samples were characterized by X-ray diffraction, differential scanning calorimetry and X-ray photoelectron spectroscopy. Corrosion resistance evaluation was carried out by measuring mass loss of samples immersed in 0.1 M H2SO4 solution, and by measuring potentiodynamic polarization curves (potential vs. current). Saturation magnetic flux density, Bs, of the samples were measured. After partial crystallization of Fe80Zr3.5Nb3.5B12Cu1 amorphous sample the corrosion resistance decreased, while for the Fe73Nb3Si15.5B7.5Cu1 the corrosion resistance increased. The decrease of Bs after treatment in the corrosion solution as observed in the nanocrystalline Fe80Zr3.5Nb3.5B12Cu1 sample was larger than that observed for both amorphous and the nanocrystalline Fe73Nb3Si15.5B7.5Cu1 samples after the same treatment. [Copyright &y& Elsevier]