The present study reports the stability profile of an antithrombotic drug: dabigatran etexilate (DAB). The drug was subjected to thermal degradation at 60 ºC and products formed were investigated by liquid chromatography-UV (LC-UV) and liquid chromatography-mass spectrometry (LC-ESI-MS). Chromatographic separation of the degradation products was performed on a GL Sciences Inc. Inertsil ODS-2 column (250 mm × 4.6 mm i.d., with a particle size of 5 µm and pore size of 110 Å) with mobile phase consisting of acetonitrile and ammonium acetate buffer (pH 5.5; 10 mmol L−1) (65:35, v/v) pumped at 1.0 mL min−1 flow rate. Column temperature was set at 30 ºC and detection at 225 nm using a UV detector. LC-UV method previously validated was extended to LC-ESI-MS for the characterization of the degradation products (DP-01 and DP-02) formed, without complicated isolation or purification processes, based on retention times and confirmation of molecular weight. Degradation kinetics of DAB was also evaluated and could be described as a first-order process (R2= 0.9900). Furthermore, no evidence of cytotoxicity in human mononuclear cells was observed for DAB degraded samples.

A stability-indicating method using MEKC was validated for the analysis of olmesartan medoxomil in tablets. Successful separation was achieved using a fused silica capillary (40 cm x 50 µm i.d.); background electrolyte consisted of a combination of 10 mmol L-1 borate buffer and 5 mmol L-1 anionic detergent sodium dodecyl sulfate (95:5; v/v) pH 6.5; hydrodynamic mode at 50 mBar for 5 s; 25 kV separation voltage at 25 ºC; and column temperature 25 ºC with detection at 257 nm. The proposed method, validated following ICH guidelines, was applied to the determination of this antihypertensive with good results compared with an LC method.

Um método simples de eletroforese capilar de zona (CZE) foi desenvolvido e validado para análise de carbonato de lodenafila em comprimidos. A metodologia de superfície de resposta foi utilizada para a otimização do pH, concentração do tampão, voltagem e temperatura. O método utilizou como eletrólito, tampão borato 50 mmol L-1, pH 10, voltagem de 15 kV. A separação foi efetuada em capilar de sílica fundida mantida a 32,5 ºC e o comprimento de onda de detecção foi de 214 nm. O método foi validado, demonstrando especificidade, linearidade (r = 0,9995), precisão (desvio padrão relativo inferior a 2%) e exatidão (99,95%). O método demonstrou ser robusto, através de avaliação por planejamento fatorial fracionário. O método CZE proposto foi aplicado com sucesso para a análise quantitativa de carbonato de lodenafila em comprimidos e os resultados, comparados com os métodos por cromatografia líquida de alta eficiência e espectrofotometria no ultravioleta, não apresentaram diferença significativa.

A simple capillary zone electrophoresis (CZE) method was developed and validated for the analysis of lodenafil carbonate in tablets. Response surface methodology was used for optimization of the pH and concentration of the buffer, applied voltage and temperature. The method employed 50 mmol L-1 borate buffer at pH 10 as background electrolyte with an applied voltage of 15 kV. The separation was carried out in a fused-silica capillary maintained at 32.5 ºC and the detection wavelength was 214 nm. The method was validated showing specificity, linearity (r = 0.9995), precision (relative standard deviation less than 2%) and accuracy (99.95%). The method proved to be robust by a fractional factorial design evaluation. The proposed CZE method was successfully applied for the quantitative analysis of lodenafil carbonate in tablets and the results compared to the high performance liquid chromatography and ultraviolet spectrophotometric methods, showed non-significant differences.

This paper evaluates the adsorption capacity of zirconocene-based silica materials in the pre-concentration of antimicrobians (tetracycline, sulfamethoxazole and trimethoprim) in aqueous medium. These materials were prepared by grafting the zirconocene onto silicas pre-treated at different temperatures. The retention capacity of these materials was evaluated by off line SPE and HPLC-UV and the proposed methodology was validated in ultrapure, tap and river water. The recovery for tetracycline was 72% (in the solid phase A) and, for sulfamethoxazole and trimethoprim was 68 and 95% in the commercial C18, respectively. The target antimicrobians were not detected in the Arroio Dilúvio (Porto Alegre - RS).

OBJETIVO: Determinar a concentração plasmática de zinco em crianças e adolescentes cirróticos e investigar a associação entre esses resultados e a ingestão dietética de zinco, os dados antropométricos e a gravidade da doença hepática. MÉTODOS: As concentrações plasmáticas de zinco foram avaliadas por espectrofotometria de absorção atômica em 30 crianças e adolescentes com cirrose (105,0±60,0 meses; 22 meninas) e 27 hígidas e sem doença hepática (122,3±47,3 meses, 14 meninas). Os dados relacionados ao zinco dietético foram avaliados por registro de ingestão alimentar de 3 dias. A antropometria incluiu peso, altura, espessura da dobra cutânea, circunferência braquial e área muscular do braço. A gravidade da doença hepática foi classificada de acordo com os critérios de Child-Pugh, MELD e PELD. RESULTADOS: As concentrações plasmáticas de zinco dos indivíduos controles e dos pacientes foram 105,69±19,46 e 75,44±24,45 μg/dL, respectivamente (p < 0,001). Nenhuma associação foi encontrada entre os índices antropométricos, a ingestão dietética e o zinco plasmático. Houve diferença estatística nas concentrações de zinco plasmático entre pacientes Child-Pugh B+C e controles (p < 0,001), e com relação ao PELD, entre pacientes abaixo e acima do ponto de corte 15 (p = 0,002). CONCLUSÃO: A prevalência de hipozincemia foi de 43% para pacientes com cirrose. A baixa concentração plasmática de zinco foi associada com a doença hepática grave; entretanto, a hipozincemia esteve presente mesmo em pacientes Child-Pugh A. Portanto, a suplementação de zinco deve ser considerada para os pacientes pediátricos cirróticos.

OBJECTIVE: To determine plasma zinc concentrations in children and adolescents with cirrhosis and to investigate the association between these results and dietary zinc intake, anthropometric data, and severity of liver disease. METHODS: Plasma zinc concentration was assessed by atomic absorption spectrophotometry in 30 children and adolescents with cirrhosis (105.0±60.0 months; 22 girls) and 27 without liver disease (122.3±47.3 months, 14 girls). Dietary zinc data were evaluated by 3-day food intake records. Anthropometry measures included height, weight, skinfold thickness, brachial circumference, and upper arm muscle size. Severity of liver disease was classified according to the Child-Pugh, MELD, and PELD criteria. RESULTS: The mean (± standard deviation) plasma zinc concentrations in control subjects and patients were 105.69±19.46 and 75.44±24.45 μg/dL, respectively (p < 0.001). No associations were found between anthropometric measures, dietary zinc intake, and plasma zinc concentration. There was statistical difference related to plasma zinc concentrations between Child-Pugh B + C patients and control subjects (p < 0.001), and concerning PELD, between patients below the cutoff score of 15 and those above (p = 0.002). CONCLUSION: The prevalence of hypozincemia was 43% for patients with cirrhosis. Although low plasma zinc concentration was associated with more severe liver disease, it was present even in some Child-Pugh A patients. Therefore, zinc supplementation should be considered for cirrhotic children.

Oito amostras, provenientes do Brasil, Chile e Argentina, de Peumus boldus Molina (Monimiaceae), espécie comum e abundante no Chile, cujas folhas são amplamente empregadas pela medicina tradicional para o tratamento de uma variedade de afecções do sistema digestivo e hepatobiliar, foram analisadas, após digestão nítrica, para a quantificação de ferro, manganês, cobre, chumbo, cromo, cobalto e níquel, por espectrofotometria de absorção atômica. Chumbo, cromo e cobalto não foram detectados (limite de detecção de 5 µg/g) em nenhuma das amostras. Todas as amostras apresentaram maior teor em ferro, que variou de 109,7 mg/kg a 315,7 mg/kg, seguido por manganês (65,5 mg/kg a 158,8 mg/kg), cobre (3,04 mg/kg a 9,16 mg/kg) e níquel (0,77 mg/kg a 4,31 mg/kg).

Eight samples, obtained from Brazil, Chile and Argentina, of Peumus boldus Molina (Monimiaceae), an abundant and widespread native tree in Chile, which leaves are widely used in folk medicine for the treatment of digestive and hepatobiliary disorders, were analyzed, after nitric digestion, for the content of iron, manganese, copper, lead, chromium, cobalt and nickel, by atomic absorption spectrophotometry. Lead, chromium and cobalt were not detected (detection limit of 5 µg/g) in any sample. The samples showed a high level of iron, which ranged from 109.7 mg/kg to 315.7 mg/kg, followed by manganese (65.5 mg/kg to 158.8 mg/kg), copper (3.04 mg/kg to 9.16 mg/kg) and nickel (0.77 mg/kg to 4.31 mg/kg).

Esta revisão tem como objetivo apresentar os novos usos da talidomida. O interesse por este fármaco é devido às suas propriedades antiinflamatórias, immunossupressoras, antiangiogênicas e até mesmo antivirais. Embora o seu mecanismo de ação seja desconhecido, resultados demonstram com sucesso o emprego deste fármaco no eritema nodoso leproso, mieloma múltiplo, doença enxerto-versus-hospedeiro e também como inibidor do vírus HIV e tratamento dos sintomas da Aids. O trabalho também mostra que apesar dos benefícios, a talidomida exige um controle muito rigoroso no que diz respeito à sua utilização e sua dispensação, devido às suas propriedades teratogênicas. Contudo, a talidomida constitui-se numa importante alternativa farmacêutica, sendo que o seu verdadeiro potencial ainda está sendo investigado.

The new uses of thalidomide are reviewed. It has recently been used as antinflammatory, immunosuppressive, antiangiogenic, and antiviral agent. Although its mechanism of action is not yet understood, the advantage of its use in several diseases, such as erythema nodosum leprosum, multiple myeloma, and graft-versus-host-disease is evident. Owing to its teratogenic properties, the use of thalidomide must be very well controlled. However, thalidomide has become a very important alternative, with new applications being studied.