Validation of a UV-spectrophotometric analytical method for determination of LPSF/AC04 from inclusion complex and liposomes

The aim of this study was to develop and validate a UV spectrophotometric method for determination of LPSF/AC04 from inclusion complex and encapsulated into liposomes. The validation parameters were determined according to the International Conference on Harmonisation (ICH) and National Health Surveillance Agency (ANVISA) guidelines. LPSF/AC04 was determined at 250 nm in methanol by a UV spectrophotometric method, exhibiting linearity in the range from 0.3 to 2 µg.mL−1 (Absorbance=0.18068 x [LPSF/AC04 µg.mL-1] + 0.00348), (r2=0.9995). The limits of detection and quantification were 0.047µg.mL−1 and 0.143µg.mL−1, respectively. The method was accurate, precise, reproducible and robust since all the samples analyzed had coefficient of variation of less than 5% and no statistically significant difference between theoretical and practical concentrations was detected. Thus, a rapid, simple, low cost and sensitive spectrophotometric method was developed and validated for determining the content of inclusion complex and liposomes containing LPSF/AC04.

O objetivo deste estudo foi desenvolver e validar um método espectrofotométrico para determinação do LPSF/AC04 em complexo de inclusão e encapsulado em lipossomas. Os parâmetros de validação foram determinados de acordo com o International Conference on Harmonisation (ICH) e Agência Nacional de Vigilância Sanitária (ANVISA). OLPSF/AC04 foi determinado a 250 nm em metanol pelo método espectrofotométrico UV, que apresenta linearidade na faixa de 0,3 a 2 µg/mL (Absorbância = 0,18068 x [LPSF/AC04 µg/mL] + 0,00348), (r2 = 0,9995). Os limites de detecção e quantificação foi 0,047 µg/mL e 0,143 µg/mL, respectivamente. O método foi exato, preciso, reprodutível e robusto e todas as amostras analisadas apresentaram coeficiente de variação menor que 5% e não houve diferença estatisticamente significante entre a concentração teórica e a prática. Assim, um método espectrofotométrico rápido, simples, sensível e de baixo custo foi desenvolvido e validado para determinar o conteúdo do LPSF/AC04 em complexos de inclusão e encapsulados em lipossomas.

Hydroxychloroquine decreases Th17-related cytokines in systemic lupus erythematosus and rheumatoid arthritis patients

OBJECTIVES: Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients. METHODS: Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients. RESULTS: We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine. CONCLUSIONS Our in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication. .

Relacao estrutura-atividade e mecanismo de acao de anticonvulsivantes derivados do 2-sulfamoilbenzoato. 1. Atividade anti-estricnina / Structure-activity relationship and mechanism of anticonvulsant action of 2-sulfamoylbenzoate derivatives. I. Anti-strychinine activity

Com o objetivo de estudar as relacoes quantitativas entre a estrutura quimica e a atividade anti-estricnina em uma serie de derivados 2-sulfamoilbenzoatos, foram determinados parametros fisico-quimicos obtidos pelo metodo CNDO/2, alguns dos quais, juntamente com a conectividade molecular, permitiram estabelecer os fatores que influem na atividade farmacologica e o possivel mecanismo de acao ao nivel molecular