Alginate-Based 3D A549 Cell Culture Model to Study Paracoccidioides Infection.

A three-dimensional (3D) lung aggregate model based on sodium alginate scaffolds was developed to study the interactions between Paracoccidioides brasiliensis (Pb) and lung epithelial cells. The suitability of the 3D aggregate as an infection model was examined using cell viability (cytotoxicity), metabolic activity, and proliferation assays. Several studies exemplify the similarity between 3D cell cultures and living organisms, which can generate complementary data due to the greater complexity observed in these designed models, compared to 2D cell cultures. A 3D cell culture system of human A549 lung cell line plus sodium alginate was used to create the scaffolds that were infected with Pb18. Our results showed low cytotoxicity, evidence of increased cell density (indicative of cell proliferation), and the maintenance of cell viability for seven days. The confocal analysis revealed viable yeast within the 3D scaffold, as demonstrated in the solid BHI Agar medium cultivation. Moreover, when ECM proteins were added to the alginate scaffolds, the number of retrieved fungi was significantly higher. Our results highlight that this 3D model may be promising for in vitro studies of host-pathogen interactions.

Total polyphenols from syzygium cumini (L) skeels fruit extract / Polifenóis totais de Ssyzygium cumini (L) skeels extrato de frutas

A precise, accurate and low cost spectrophotometric method was developed and validated for routine determination of total polyphenols, as pyrogallic acid equivalents, from the percolated and lyophilized extract of Syzygium cumini (L.) Skeels fruits. Validation was assessed experimentally and data were rigorously treated by statistical analysis. Analytical parameters were: linearity, interval (range), precision and recovery/accuracy, limit of detection (LOD, μg mL-1) and limit of quantification (LOQ, μg mL-1). The visible spectrophotometric method presented linearity (r² = 0.9979 ± 0.0010) over the concentration range 0.25-7.5 μg mL-1 of standard pyrogallic acid, precision < 2.918171 percent, recovery/accuracy ranging from 96.228693 to 107.17701 percent, LOD = 0.21 μg mL-1 and LOQ = 0.64 μg mL-1.

Um método espectrofotométrico preciso, rigoroso e de baixo custo foi desenvolvido e validado para a determinação de polifenóis totais, utilizando-se como padrão o ácido pirogálico. O extrato dos frutos de Syzygium cumini (L.) Skeels foi preparado empregando-se o método de percolação com posterior liofilização. A validação foi executada experimentalmente e os dados foram submetidos à análise estatística. Os parâmetros analíticos considerados foram: linearidade, intervalos de precisão e de recuperação, limite de detecção (LD, μg.mL-1) e o limite de quantificação (LQ, μg.mL-1). O método espectrofotométrico apresentou linearidade (r² = 0,9979 + 0,0010) ao longo do intervalo de concentração de 0,25-7,5 μg mL-1 de ácido pirogálico, padrão de precisão menor do que 2,918171 por cento; recuperação/precisão entre 96,228693 a 107,17701 por cento, e LD = 0,21 μg-mL-1 e LOQ = 0,64 μg mL-1.

Accelerated chemical stability data of O/W fluid emulsions containing the extract of Trichilia catigua Adr. Juss (and) Ptychopetalum olacoides Bentham

Development of topical dosage forms requires physical, physicochemical and chemical assays that provide, as soon as possible, the formulation with the best stability profiles. This study evaluated the stability of O/W fluid emulsions, by total flavonoids determination, expressed in rutin, containing the standardized extract of Trichilia catigua Adr. Juss (and) Ptychopetalum olacoides Bentham. Samples were evaluated for 90 days stored at 24.0 ± 2.0 ºC, 5.0 ± 0.5 ºC and 40.0 ± 0.5 ºC, following a protocol for the assessment of accelerated chemical stability assay, also known as Normal Stability Test. A sensitive UV-spectrophotometric method at 361.0 nm was previously validated for the determination of the active substance. By Normal Stability Test, the O/W fluid emulsions presented acceptable chemical stability, for at least 90 days, when the samples were stored at 24.0 ± 2.0 ºC and 5.0 ± 0.5 ºC. The storage condition at 40.0 ± 0.5 ºC has accelerated the degradation process of the total flavonoids, consequently, those O/W emulsions containing this kind of natural active substance or a similar preparation must not be stored at elevated temperatures.

O desenvolvimento de formas farmacêuticas tópicas necessita ensaios físicos, físico-químicos e químicos que selecionem rapidamente a formulação de melhor desempenho de estabilidade. Este estudo avaliou a estabilidade de emulsões O/A fluidas, por meio da determinação de flavonóides totais, expressos em rutina, contendo o extrato padronizado de Trichilia catigua Adr. Juss (e) Ptychopetalum olacoides Bentham. As amostras foram armazenadas a 24,0 ± 2,0 ºC; 5,0 ± 0,5 ºC e 40,0 ± 0,5 ºC durante 90 dias e foram avaliadas segundo o protocolo para a determinação da estabilidade acelerada, conhecida como Teste de Estabilidade Normal. A quantificação da substância ativa foi determinada por espectrofotometria na região do ultravioleta a 361,0 nm, previamente validado. Após os ensaios de estabilidade, as emulsões O/A fluidas apresentaram estabilidade adequada, pelo menos, no período de 90 dias, quando armazenadas a 24,0 ± 2,0 ºC e 5,0 ± 0,5 ºC. A condição de armazenamento a 40,0 ± 0,5 ºC acelerou a cinética de degradação dos flavonóides totais, expressos em rutina, portanto, preparações possuindo esta categoria de substância ativa natural ou formulações similares não devem ser armazenadas em temperaturas elevadas.