Improving in the antibacterial activity and the antioxidant properties of chemically modified extracts of Zinnia peruviana

In the present work we investigate the changes in the antibacterial activity and the antioxidant properties of modified extracts of Zinnia peruviana (L.) L. campesterol, stigmasterol and β-sitosterol were identified as majortriterpenoids in the natural extract, by CG-EIMS and NIST Mass Spectrometry Data Center. The acetonic extract was chemically modified by reactions of acid hydrolysis, sulfonylation, acetylation, methylation and silylation. The in-vitro antibacterial activity was evaluated against Gram-positive and Gram-negative bacteria. The acetonic extract showed significant activity only against Gram-positive bacteria (MIC/MBC = 2/9 mg/mL). The hydrolyzed extract improve the bioactivity to both, Gram-positive and Gram-negative (MIC/MBC = 2/8 mg/mL). Selectively, the acetylated extract was only effective toward Staphylococcus (MIC/MBC = 7/7 mg/mL). The tosylated extract was active against Gram-positive and P. aeruginosa (MIC/MBC = 24/24 mg/mL) and the silylated against Grampositiveand E. coli. (MIC/MBC = 15/15 mg/mL). The antioxidant activity was determining by DPPH and ABTS assays. Hydrolyzed extract increased the antioxidant properties (DPPH, IC50,(mg/mL) = 0.077 ± 0.007; ABTS IC50,(mg/mL) = 0.032 ± 0.005). The acylated and alkylated extracts reduce the bioactivity and silylated derivative eliminated the bioactivity. These results could be considered as a possible strategy to obtain antimicrobial agents from herbal medicines.Fil: Mohamed, Ana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Salinas, A.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Mattana, C.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Satorres, S.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Ortega, C.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Favier, L.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Cifuente, Diego Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin

Expressão imunoistoquímica do HER-2/NEU-CERBB-2 em pacientes com adenocarcinoma do estômago

Objectives: To determine the prevalence of Her-2/Neu-cerbb-2 in the gastric mucosa of patients with gastric adenocarcinoma in a brazilian patient group. Methods: The immunohistochemical expression of Her-2/Neu was studied in 37 formalin-fixed paraffin– embedded tissue sections. Results: The immunohistochemical reaction produced by the anti-HER-2/Neu antibody was positive in two cases (5.4%). Conclusion: The low prevalence of Her-2/Neu observed in these southern brazilian cases is probably due to the great number of poorly differentiated cancers in this serie.Objetivo: Determinar a prevalência do Her-2/Neu-CerbB-2 na mucosa de pacientes com adenocarcinoma de estômago em um grupo de doentes brasileiros. Métodos: A expressão imunoistoquímica do Her-2/Neu foi estudada em 37 amostras de tecidos fixados em formalina e embebidos em parafina. Resultados: A reação imunoistoquímica produzida pelo anticorpo HER-2/Neu foi positiva em dois pacientes (5.4%). Conclusão: A baixa prevalência Her-2/Neu observada neste grupo de pacientes é provavelmente devida ao grande número de tumores pouco diferenciados encontrados nesta série