Tuning Fe3O4 for sustainable cathodic heterogeneous electro-Fenton catalysis by acetylated chitosan.

Peroxidase-like catalysts are safe and low-cost candidates to tackle the dilemma in constructing sustainable cathodic heterogeneous electro-Fenton (CHEF) catalysts for water purification, but the elusive structure-property relationship of enzyme-like catalysts constitutes a pressing challenge for the advancement of CHEF processes in practically relevant water and wastewater treatment. Herein, we probe the origins of catalytic efficiency in the CHEF process by artificially tailoring the peroxidase-like activity of Fe3O4 through a series of acetylated chitosan-based hydrogels, which serve as ecofriendly alternatives to traditional carbon shells. The optimized acetylated chitosan wrapping Fe3O4 hydrogel on the cathode shows an impressive activity and stability in CHEF process, overcoming the complicated and environmentally unfavored procedures in the electro-Fenton-related processes. Structural characterizations and theoretical calculations reveal that the amide group in chitosan can modulate the intrinsic redox capacity of surficial Fe sites on Fe3O4 toward CHEF catalysis via the neutral hydrogen bond. This work provides a sustainable path and molecule-level insight for the rational design of high-efficiency CHEF catalysts and beyond.

[Platelet-rich plasma injection for the treatment of atrophic fracture nonunion].

OBJECTIVE: To explore clinical effects of platelet rich plasma (PRP) injection in treating atrophic fracture nonunion. METHODS: From March 2015 to March 2017, 15 patients with atrophic fracture nonunion were treated with PRP injection, including 10 males and 5 females, aged from 23 to 56 years old with an average age of (40.0±9.1) years old, the time of fracture nonunion ranged from 6 to 14 months with an average of (8.87±2.45) months. Preparing PRP by extracting 60 to 100 ml peripheral blood. PRP platelet count ranged from 587 to 1 246 with an average of (947.13±158.58) ×10 9 /L. Under the perspective, 13 to 20 ml PRP were injected into the fracture end, and each injection was performed once on the first and the second week of the treatment. Complications such as whether the limb was shortened, angulation, and rotational deformity and radiological examination were observed. RESULTS: All patients were followed up from 6 to 12 months with an average of (6.8± 2.1) months. No shortening, angulation, and rotational deformity occurred. Thirteen patients had fracture healing, the time ranged from 4 to 6 months with an average of (4.8±0.7) months. Two patients had no completely porosis at 12 months during following up, and 1 patient occurred bolt loose. Other patients had no complications. CONCLUSION: The stability of fracture ends of atrophic fracture nonunion after internal fixation is an indication for local PRP injection. PRP treatment for atrophic fractures could completed under local anesthesia, and it has advantages of safe operation and reliable efficacy.

[Preoperative traction of calcaneus in the treatment of Rüedi-Allgöwer II and III pilon fracture].

OBJECTIVE: To explore the role of preoperative calcaneal traction in the treatment of Rüedi-Allgöwer II and III Pilon fracture. METHODS: From March 2005 to March 2010, 56 patients with Rüedi-Allgöwer II and III Pilon fracture were treated by calcaneal traction internal fixation on the second phase. There were 42 males and 14 females with an average age of 34.6 years old (ranged 18 to 68). Clinical outcomes were assessed according to Tormette Pilon and tibia fracture standard. RESULTS: All patients were followed up from 9 to 36 months with an average of 18 months. All fracture obtained bone healing, the time ranged from 4.5 to 8.2 months with a mean of 6.2 months. No deep infection, breakage of internal fixation and other complications occurred. According to Tornetta evaluation criteria,35 cases got excellent results, 18 cases good,and 3 cases fair. CONCLUSION: Preoperative calcaneal traction as a temporary fixing measure can provide a good environment for successful operation, and is an essential foundation for recovering functional, painless, load, movable joint.