Human Islet Microtissues as an In Vitro and an In Vivo Model System for Diabetes

Loss of pancreatic β-cell function is a critical event in the pathophysiology of type 2 diabetes. However, studies of its underlying mechanisms as well as the discovery of novel targets and therapies have been hindered due to limitations in available experimental models. In this study we exploited the stable viability and function of standardized human islet microtissues to develop a disease-relevant, scalable, and reproducible model of β-cell dysfunction by exposing them to long-term glucotoxicity and glucolipotoxicity. Moreover, by establishing a method for highly-efficient and homogeneous viral transduction, we were able to monitor the loss of functional β-cell mass in vivo by transplanting reporter human islet microtissues into the anterior chamber of the eye of immune-deficient mice exposed to a diabetogenic diet for 12 weeks. This newly developed in vitro model as well as the described in vivo methodology represent a new set of tools that will facilitate the study of β-cell failure in type 2 diabetes and would accelerate the discovery of novel therapeutic agents.     

基于全内反射和减色滤波法的新型反射式彩色显示技术

我们提出了采用减色滤光膜（subtractive color filltering)装置控制棱镜微结构全内反射（Total Interal Reflection,TIR)的一种反射式彩色显示技术。这种棱镜的表面能够有效地改变射向观察者的环境光线的方向而减色。采用减色波光法能得到明亮而易辨认的低功耗彩色图象,它比常规RGB反射式彩色LCD显示的反射率改善了4倍。该技术的主要优点是仅用约半微米起伏（about a half-micron movement）的可控减色滤波膜就能够在高反射和亮彩色态之间进行转换。