No abstract

Oral dosage forms have many obvious advantages like simple, painless and self-administered. While the bioavailability of drugs are always low for they are unstable and usually degraded within gastrointestinal tract. Curcumin, a multifunction native compound, can be used in curing many diseases while the oral bioavailability is relatively low, limiting its clinical effectiveness. The aim of this study was to investigate the method of increasing the bioavailability by the addition of biotin, which was a kind of vitamin helping the liposomes to uptake by biotin receptors. In situ rat Single-Pass Intestinal Perfusion Model (SPIP) was applied to investigate the different content of biotin and caco-2 cells monolayer model was established to mimic the intestinal tract in drug transportation study. As the results shows that biotin decorated liposomes (biotin-PEG-DSPE-Lip) had a better cellular uptake and transportation rate compared to biotin undecorated ones (PEG-DSPE-Lip). It indicated that the bioavailability of curcumin had been increased.

Based on the time series of market price of risk (MPR) corresponding to the A-Share indices of SSE & SzSE, we make an inquiry into the impact of investor sentiment on the MPR. We adopt the vector autoregression (V AR) methodology, and employ impulse response functions to demonstrate the extend to which investor sentiment influences MPR. This approach is due to the fact that both investor sentiment and MPR are two important state variables in the system of stock market. Although we use the same investor sentiment proxy as previous literatures, we decompose this proxy into two components: the rational and the irrational, and explore the exclusive impact of each component to the MPR. We also consider the mutual influence of investor sentiment in Shanghai Stock Exchange (SSE) and Shenzhen Stock Exchange (SzSE) to their MPRs. We find that the response of MPR to a standard shock from the rational component of investor sentiment is significantly negative in the second period, but insignificant to the irrational component.We also find that MPR is significantly different in periods when investor sentiment is pessimistic and optimistic, respectively. More precisely, during the pessimistic period, MPR is positive, while in the optimistic period, MPR is probably negative.