RESUMO
BACKGROUND: Sanguinarine (SAG), a benzophenanthridine alkaloid, occurs in Papaveraceas, Berberidaceae and Ranunculaceae families. Studies have found that SAG has antioxidant, anti-inflammatory, and antiproliferative activities in several malignancies and that it exhibits robust antibacterial activities. However, information reported on the action of SAG against Providencia rettgeri is limited in the literature. Therefore, the present study aimed to evaluate the antimicrobial and antibiofilm activities of SAG against P. rettgeri in vitro. METHODS: The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of SAG against P. rettgeri. The intracellular ATP concentration, intracellular pH (pHin), and cell membrane integrity and potential were measured. Confocal laser scanning microscopy (CLSM), field emission scanning electron microscopy (FESEM), and crystal violet staining were used to measure the antibiofilm formation of SAG. RESULTS: The MIC of SAG against P. rettgeri was 7.8 µg/mL. SAG inhibited the growth of P. rettgeri and destroyed the integrity of P. rettgeri cell membrane, as reflected mainly through the decreases in the intracellular ATP concentration, pHin and cell membrane potential and significant changes in cellular morphology. The findings of CLSM, FESEM and crystal violet staining indicated that SAG exhibited strong inhibitory effects on the biofilm formation of P. rettgeri and led to the inactivity of biofilm-related P. rettgeri cells.
RESUMO
OBJECTIVES: The aim of this study was to investigate the effects of formaldehyde exposure on Th17 and Th22 cells and its relevance to human occupational allergic contact dermatitis (OACD). METHODS: Circulating IL17-/IL22-secreting cells and serum IL17/IL22 levels in formaldehyde-exposed workers at Occupational Exposure Limit and nonexposed controls were assessed. RESULTS: The IL17 and IL22 cell population were detected in both CD3CD8 and CD3CD8 cells. The percentages of circulating IL17 and IL22 T cells in the workers with and without ACD history were all elevated, which were more remarkable in the ones with ACD history. Serum levels of IL17 and IL22 between the workers and controls were not significantly different. CONCLUSIONS: Low-level formaldehyde exposure may increase circulating IL17-/IL22-producing T cells (CD8 and CD8), possibly involved in the development of human OACD. But it may not alter serum levels of IL17/IL22 before the appearance of OACD symptoms.