Xiamen University

About: Xiamen University is a education organization based out in Amoy, Fujian, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 50472 authors who have published 54480 publications receiving 1058239 citations. The organization is also known as: Amoy University & Xiàmén Dàxué.

Cytosporone B is an agonist for nuclear orphan receptor Nur77

Abstract: Nuclear orphan receptor Nur77 has important roles in many biological processes. However, a physiological ligand for Nur77 has not been identified. Here, we report that the octaketide cytosporone B (Csn-B) is a naturally occurring agonist for Nur77. Csn-B specifically binds to the ligand-binding domain of Nur77 and stimulates Nur77-dependent transactivational activity towards target genes including Nr4a1 (Nur77) itself, which contains multiple consensus response elements allowing positive autoregulation in a Csn-B-dependent manner. Csn-B also elevates blood glucose levels in fasting C57 mice, an effect that is accompanied by induction of multiple genes involved in gluconeogenesis. These biological effects were not observed in Nur77-null (Nr4a1-/-) mice, which indicates that Csn-B regulates gluconeogenesis through Nur77. Moreover, Csn-B induced apoptosis and retarded xenograft tumor growth by inducing Nur77 expression, translocating Nur77 to mitochondria to cause cytochrome c release. Thus, Csn-B may represent a promising therapeutic drug for cancers and hypoglycemia, and it may also be useful as a reagent to increase understanding of Nur77 biological function.

A Probabilistic Method for Image Enhancement With Simultaneous Illumination and Reflectance Estimation

Abstract: In this paper, a new probabilistic method for image enhancement is presented based on a simultaneous estimation of illumination and reflectance in the linear domain We show that the linear domain model can better represent prior information for better estimation of reflectance and illumination than the logarithmic domain A maximum a posteriori (MAP) formulation is employed with priors of both illumination and reflectance To estimate illumination and reflectance effectively, an alternating direction method of multipliers is adopted to solve the MAP problem The experimental results show the satisfactory performance of the proposed method to obtain reflectance and illumination with visually pleasing enhanced results and a promising convergence rate Compared with other testing methods, the proposed method yields comparable or better results on both subjective and objective assessments

Toxic Reactive Oxygen Species Enhanced Synergistic Combination Therapy by Self-Assembled Metal-Phenolic Network Nanoparticles.

Abstract: Engineering functional nanomaterials with high therapeutic efficacy and minimum side effects has increasingly become a promising strategy for cancer treatment. Herein, a reactive oxygen species (ROS) enhanced combination chemotherapy platform is designed via a biocompatible metal-polyphenol networks self-assembly process by encapsulating doxorubicin (DOX) and platinum prodrugs in nanoparticles. Both DOX and platinum drugs can activate nicotinamide adenine dinucleotide phosphate oxidases, generating superoxide radicals (O2•- ). The superoxide dismutase-like activity of polyphenols can catalyze H2 O2 generation from O2•- . Finally, the highly toxic HO• free radicals are generated by a Fenton reaction. The ROS HO• can synergize the chemotherapy by a cascade of bioreactions. Positron emission tomography imaging of 89 Zr-labeled as-prepared DOX@Pt prodrug Fe3+ nanoparticles (DPPF NPs) shows prolonged blood circulation and high tumor accumulation. Furthermore, the DPPF NPs can effectively inhibit tumor growth and reduce the side effects of anticancer drugs. This study establishes a novel ROS promoted synergistic nanomedicine platform for cancer therapy.