RESUMO
This paper proposes a novel color medical image encryption method based on mean shift algorithm and fractional-order hyperchaotic system. Firstly, color medical images were divided into lesion area, detection area, and edge area by using mean shift clustering. Low-value pixels and zero-value pixels in the edge region are abandoned to improve the encryption efficiency. Secondly, the doctor-patient information is embedded into the pixel matrix of the lesion region by using discrete wavelet transform and singular value decomposition. Thirdly, the pixels of the lesion region and the detection region are processed by using fractional-order hyperchaotic system. Finally, the color medical image embedded with doctor-patient information can be quickly encrypted. Security analysis shows that the encryption method has not only strong robustness and security, but also good performance against various attacks. SPNA and CA results: (a) s1-DE-SPNA, (b) s2-DE-SPNA, (c) s3-DE-SPNA, (d) s4-DE-SPNA; (e) s1-DE-CA, (f) s2-DE-CA, (g) s3-DE-CA, (h) s4-DE-CA.
Assuntos
Segurança Computacional , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Análise de OndaletasRESUMO
BACKGROUND: T-cell dysregulation and T-cell-related cytokine abnormalities are involved in the pathogenesis of immune thrombocytopenia (ITP). One of our previous studies showed that elevated IL-22 correlated to Th1 and Th22 cells plays an important role in the immunopathogenesis of ITP. In this study, we aimed to investigate the effects of high-dose dexamethasone(HD-DXM) on IL-22 production and on the IL-22-producing T-cell subsets in ITP patients. METHODS: IL-22 plasma levels and the percentages of Th1, Th17, and Th22 cells were determined by enzyme-linked immunosorbent assay and flow cytometry in 25 ITP patients receiving DXM 40 mg/day for 4 consecutive days. RESULTS: Plasma IL-22 concentrations and the percentages of Th1 and Th22 cells were significantly increased in pretherapy patients relative to controls (P<0.05), but the percentage of Th17 cells was not. HD-DXM administration reduced IL-22 production and corrected the imbalance between Th1 and Th22 subsets. IL-22 levels were positively correlated with Th1 and Th22 cells in ITP patients before and after HD-DXM treatment. CONCLUSION: These results suggest that HD-DXM may regulate the production of IL-22 in ITP, possibly by correcting Th1 and Th22 polarization.