In vivo and in vitro immunomodulatory and anti-inflammatory effects of total flavonoids of astragalus

Background: Astragali Radix has long been used to improve immune function in traditional Chinese medicine. However, its main active components and potential immunomodulatory or anti-inflammatory activities have not been elucidated. In the present study, the immunomodulatory and anti-inflammatory activities of total flavonoids of Astragalus (TFA) isolated from Astragali Radix were evaluated by using in vivo animal models and in vitro cell models.Materials and Methods: The in vivo Immunomodulatory and anti-inflammatory activities of TFA were assessed by measuring macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, ear edema test in mice, paw edema test in rats, vascular permeability test in mice and granuloma test in rats. The in vitro Immunomodulatory and  anti-inflammatory activities of TFA were assessed by examining its effect on cytokine and mediator production in un-stimulated and LPS-stimulated murine RAW 264.7 macrophages.Results: The results of in vivo experiments showed that TFA enhanced macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, and attenuated mouse ear edema, rat paw edema, mouse vascular permeability and rat granuloma formation. The results of in vitro  experiments showed that TFA stimulated the production of NO and cytokine TNF-α, IL-1β, IL-6 and IFN-γ in un-stimulated RAW 264.7 macrophages, and inhibited the overproduction of these inflammatory mediators in LPS-stimulated RAW 264.7 macrophages in a dose-dependent manner without exerting cytotoxicity.Conclusion: These results of this study indicate that TFA have potential immunostimulatory and anti-inflammatory effects.Key words: Total flavonoids of Astragalus (TFA), Immunomodulation,  Anti-inflammation, In vivo, In vitr

Synthesis and characterization of useful polymer-based surface layers and bulk materials

This dissertation describes four projects: 1) development of a procedure for quantifying multi-step reactions for the immobilization of protein on gold and silica surfaces; 2) demonstration that observation of three-regime kinetics of formation of polymer brushes by means of the grafting-to approach is dependent on grafting conditions; 3) development of a sensor that can be used for quantitative detection of Bisphenol A (BPA) in aqueous media; 4) development of a chondroitin sulfate-based synthetic hydrogel to mimic the mechanical properties of the nucleus pulposus (in human intervertebral discs). The first three above were projects in surface modification, and for these, the quartz crystal microbalance played a key role. The fourth project was synthesis of bulk polymers and for this, dynamic mechanical analysis played a key role. The existence of quantitative analysis methods for the immobilization of proteins is relevant, because proteins are used increasingly in immobilized form for research on their interactions with various ligands. The understanding of three-regime kinetics is important, because of its role in surface tailoring and the potential it offers for creating multifunctional surfaces. A sensor that measures the amount of BPA in aqueous media is relevant, because surface waters are still polluted with this endocrine-disrupting chemical. Finally, a hydrogel with properties that duplicate those of the human nucleus pulposus is important, because the health care establishment is currently considering implants that replace the nucleus pulposus.Ph.D., Chemistry -- Drexel University, 201