Hyaluronic acid-cyclodextrin encapsulating paeonol for treatment of atopic dermatitis.

The cyclodextrin (CD) was grafted onto hyaluronic acid (HA) to form a topical delivery carrier (HACD) in which Paeonol was loaded in its CD cavity and self-assemble into the polymeric micelles (HACD-PAE) for the treatment of atopic dermatitis. Fluorescence microscope observed that HACD could fast penetrate into the skin and remain stable within 12 h. In vitro penetration test (IVPT) results showed the PAE retentions of HACD-PAE group in the stratum corneum and dermis were 3.35 and 1.78 times improvement than that of PAE group. ATR-FTIR and H&E staining assays indicated HACD could increase the gap of keratinocytes by interacting with corneum lipids and loosening the keratin. Furthermore, HACD-PAE showed the best therapeutic effect on atopic dermatitis mice. Thus HACD could be a promising skin-specific delivery carrier, not only promoting the drug penetrating but increasing its remaining in the skin and play the skin disease therapy and skin-care role.

Effects of hyaluronic acid with different molecular weight on the transdermal absorption of reduced glutathione / 中国药科大学学报

@#This paper aimed at studying the effects of hyaluronic acid (HA) with different molecular weights on the transdermal absorption and retention of reduced glutathione (GSH) in the isolated skin of SD rats. Franz diffusion cell method was used to investigate the effects with different molecular weights HA on the in vitro transdermal penetration of GSH and the storage in different layers of the skin. AutoDock molecular docking was used to study the interaction between GSH and HA. Attenuated total reflection Fourier transformed infrared spectroscopy (ATR-FTIR) and H&E section staining were used to characterize the changes and effects of lipids and proteins in the rat stratum corneum after HA acts on the skin. The results of in vitro transdermal experiments showed that HA with different molecular weights had a significant impact on the amount of GSH passing through the skin, that as the molecular weight of HA increased, the effect of preventing GSH from passing through the skin became stronger, that in terms of skin storage, HA with different molecular weights could increase the storage of GSH in the stratum corneum, and that HA with a molecular weight below 7K could also significantly increase the storage of GSH in the dermis. The molecular docking results showed that HA and GSH had a relatively strong interaction, which could form intermolecular hydrogen bonds; and the results of ATR-FTIR and H&E staining showed that HA could interact with lipids and keratins in the stratum corneum of the skin. Such interaction can increase the permeability of the stratum corneum of the drug, however, as a water-soluble GSH, it may be involved in the formation of intermolecular hydrogen bonds with HA. In the structure of HA hydrogel, the amount of GSH drug passing through the intact skin is reduced; but at the same time, this interaction also provides a reservoir for the formation of GSH, thus increasing its storage in the skin. Through comparison of the storage capacity of GSH in the stratum corneum and dermis of the isolated skin due to the increase of HA with different molecular weights, it has been found that the storage capacity of HA with low relative molecular weight is the best.

Satellite observations and modeling of oil spill trajectories in the Bohai Sea.

On June 4 and 17, 2011, separate oil spill accidents occurred at two oil platforms in the Bohai Sea, China. The oil spills were subsequently observed on different types of satellite images including SAR (Synthetic Aperture Radar), Chinese HJ-1-B CCD and NASA MODIS. To illustrate the fate of the oil spills, we performed two numerical simulations to simulate the trajectories of the oil spills with the GNOME (General NOAA Operational Modeling Environment) model. For the first time, we drive the GNOME with currents obtained from an operational ocean model (NCOM, Navy Coastal Ocean Model) and surface winds from operational scatterometer measurements (ASCAT, the Advanced Scatterometer). Both data sets are freely and openly available. The initial oil spill location inputs to the model are based on the detected oil spill locations from the SAR images acquired on June 11 and 14. Three oil slicks are tracked simultaneously and our results show good agreement between model simulations and subsequent satellite observations in the semi-enclosed shallow sea. Moreover, GNOME simulation shows that the number of 'splots', which denotes the extent of spilled oil, is a vital factor for GNOME running stability when the number is less than 500. Therefore, oil spill area information obtained from satellite sensors, especially SAR, is an important factor for setting up the initial model conditions.