PVA-based bulk microneedles capable of high insulin loading and pH-triggered degradation for multi-responsive and sustained hypoglycemic therapy.

"Closed-loop" insulin-loaded microneedle patche shows great promise for improving therapeutic outcomes and life quality for diabetes patients. However, it is typically hampered by limited insulin loading capacity, random degradation, and intricate preparation procedures for the independence of the "closed-loop" bulk microneedles. In this study, we combined the solubility of microneedles and "closed-loop" systems and designed poly(vinyl alcohol)-based bulk microneedles (MNs@GI) through in situ photopolymerization for multi-responsive and sustained hypoglycemic therapy, which significantly simplified the preparation process and improved insulin loading. GOx/insulin co-encapsulated MNs@GI with a phenylboronic ester structure improved glycemic responsiveness to control the insulin release under high glucose conditions and reduced inflammation risk in the normal skin. MNs@GI could further degrade to increase insulin release due to the crosslinked acetal-linkage hydrolysis in the presence of gluconic acid, which was caused by GOx-mediated glucose-oxidation in a hyperglycemic environment. The in vivo results showed that MNs@GI effectively regulated glycemic levels within the normal range for approximately 10 h compared to that of only insulin-loaded microneedles (MNs@INS). Consequently, the highly insulin-loaded, multi-responsive, and pH-triggered MN system has tremendous potential for diabetes treatment.

Mapping human vulnerability to chemical accidents in the vicinity of chemical industry parks.

China is suffering from severe pollution accidents which may have catastrophic impacts on the local population and environment. Some questions are unclear to local governments and industry operators like "who are vulnerable to the chemical risks?" and "what is the magnitude of vulnerability?". This paper concentrates on exploring the concepts of human vulnerability and the methodology of analyzing human vulnerability to chemical accidents in the vicinity of chemical industry parks. A conceptual model of human vulnerability to chemical accidents is developed, revealing the roots of human vulnerability and emphasizing its role in risk management. A geographical information system (GIS)-based methodology for mapping vulnerability is proposed and applied to the Nanjing Chemical Industry Park in China. By combining physical vulnerability and social vulnerability spatially, the total vulnerability is revealed to better respond to accidents. It is proposed to improve traffic lines and allocation of medical services, and include vulnerability assessment in land-use planning to reduce future risks. In other words, it seems feasible and effective to reveal physical, social and total vulnerability of residents in the vicinity of chemical risk sources.