Fabrication of "Spongy Skin" on Diversified Materials Based on Surface Swelling Non-Solvent-Induced Phase Separation.

Porous surfaces have attracted tremendous interest for customized incorporation of functional agents on biomedical devices. However, the versatile preparation of porous structures on complicated devices remains challenging. Herein, we proposed a simple and robust method to fabricate "spongy skin" on diversified polymeric substrates based on non-solvent-induced phase separation (NIPS). Through the swelling and the subsequent phase separation process, interconnected porous structures were directly formed onto the polymeric substrates. The thickness and pore size could be regulated in the ranges of 5-200 and 0.3-0.75 µm, respectively. The fast capillary action of the porous structure enabled controllable loading and sustained release of ofloxacin and bovine albumin at a high loading dosage of 79.9 and 24.1 µg/cm2, respectively. We verified that this method was applicable to diversified materials including polymethyl methacrylate, polystyrene, thermoplastic polyurethane, polylactide acid, and poly(lactic-co-glycolic acid) and can be realized onto TCPS cell culture plates. This NIPS-based method is promising to generate porous surfaces on medical devices for incorporating therapeutic agents.

A Bioinspired Hydrogel-Elastomer Hybrid Surface for Enhanced Mechanical Properties and Lubrication.

Developing surfaces that realize lubrication and durable wear resistance under high pressure has great implications in areas ranging from electromechanical systems to advanced biomedical devices but has proven challenging. Inspired by the zonal and transitional structure of articular cartilage, we fabricate a hydrogel-elastomer hybrid surface, where the hydrogel interpenetrates into the polymer elastomer substrate as a transitional and bonding zone, that exhibits a low coefficient of friction and wear resistance under a high load. First, we entrap benzophenone within the surface of polymer substrates such as polydimethylsiloxane, polyvinylchloride, and polyurethane. The hybrid surface is then achieved through initiating polymerization of the acrylamide monomer on the polymer surface upon ultraviolet irradiation. We observe an interpenetration area of the hydrogel and the polymer substrate. The hybrid surface shows a low coefficient of friction (∼0.05) under a very high load (over 100 atm contact pressure). It conserves the lubrication property over 100,000 cycles under a 10.9 MPa pressure and shows slight wear. This work brings a new perspective on designing surfaces with a lubrication property and wear resistance, showing broad applications.

A photodynamic antibacterial spray-coating based on the host-guest immobilization of the photosensitizer methylene blue.

In the "post-antibiotic era", healthcare-associated infection has become a global problem that threatens public health and causes huge economic losses. The development of antibacterial coatings based on non-antibiotic strategies is particularly important as drug-resistant bacteria continue to evolve. Photodynamic coatings are a high potential method to treat bacteria, however, the aggregation of photosensitizers on the coating affects the photodynamic capacity seriously. Herein, a photodynamic coating is developed based on the host-guest interaction between ß-cyclodextrin and the photosensitizer methylene blue (MB). The host-guest interaction avoids aggregation of MB and results in a high singlet oxygen quantum yield. Consequently, efficient photoantibacterial activity towards methicillin-resistant Staphylococcus aureus is achieved by the photodynamic coating with very low MB density (0.53 ± 0.06 µg cm-2).

Pharmacoeconomics evaluation of morphine, MS contin and oxycodone in the treatment of cancer pain.

OBJECTIVE: To analyze cost-effectiveness of morphine, MS contin and oxycodone in the treatment of cancer pain, providing guidance for rational drug use in the clinic. METHODS: Confirmed by histology, a total of 171 patients with various cancers who required analgesic treatment were selected and divided into 3 groups, 57 cases for each group, given morphine, MS contin and oxycodone, respectively. If there appeared a poor short-term effect or aggravated sudden pain during the treatment, a short-acting morphine injection was given and adverse reactions were processed by symptomatic treatment. The pain relief rate and adverse reactions of groups were observed and pharmacoeconomics evaluation was undertaken. RESULTS: The pain relief rates with morphine, MS contin and oxycodone were 89.5%(51/57), 91.2%(52/57) and 93.0%(53/57), respectively, with no difference samong groups (χ2=4.4489, P=0.6162). The occurrence rates of adverse reactions were 59.7%(34/57), 54.4%(31/57) and 43.9%(25/57), again with no significant variation (P>0.05). The ratios of cost-effectiveness (C/E) for the 3 groups were 14.6±7.21, 15.0±7.44 and 16.1±8.10. When the price of 3 kinds of analgesics was reduced by 10%, the ratios of cost-effectiveness were 12.2±6.53, (13.4±6.08 and 14.5±6.74 but there was no differences when compared with before the price adjustment (t=1.86, P=0.0651; t=1.30, P=0.1948; t=1.17, P=0.2453). CONCLUSION: Morphine, MS contin and oxycodone give similar pain relief and adverse reaction rates but of all, morphine is the preferred drug for the treatment of cancer pain from the perspective of pharmacoeconomics.

[Effect of Qingkailing injection on rat CYP1A2 and CYP2D6 activity].

OBJECTIVE: The present study investigates the influence of Qingkailing injection on rat liver CYP1A2 and CYP2D6 activity in vivo and in vitro, respectively. METHOD: We employed HPLC to measure the metabolites of caffeine in the whole blood and calculated the ratio be between the metabolite and caffeine, which was used as index to evaluate the effect of Qingkailing injection on rat CYP1A2 activity in vivo; We also detected the CYP1A2 and CYP2D6 activity in microsomal reconstituted system by analysis of phenacetin metabolism and dextromethorphan metabolism with HPLC. RESULT: The metabolism of caffeine in treated groups was (15.9 +/- 3.8)%, (14.5 +/- 1.8)%, (12.3 +/- 1.2)%, with different concentration of Qingkailing injection (0.15, 0.3, 0.6 mL x kg(-1)) compared with (16.8 +/- 5.9)% in the control group, which was no significant difference among groups. In rat liver microsomal reconstituted system, Qingkailing injection has no inhibitory effect on CYP2D6 activity while the group with high dose has inhibitory effect on rat CYP1A2. CONCLUSION: Qingkailing injection has no inhibitory effect on rat CYP1A2 and CYP2D6 in vivo and in vitro.