Application of personalized spacers made with 3D-printed mold in the two-stage procedure for periarticular infection.

BACKGROUND: Cement spacers treat periarticular infection after bone tumor resection in patients with bone defects. Complications such as poor joint function, poor soft tissue reconstruction, and poor postoperative daily living ability are present. We present a case of periarticular infection treated successfully after distal femoral osteosarcoma surgery with a personalized spacer made with a 3D-printed mold. CASE REPORT: A two-stage procedure was performed on an 18-year-old patient with high-grade conventional osteosarcoma of the left distal femur. After two biopsies, the boy developed a periarticular infection of the affected limb during neoadjuvant chemotherapy. We had a microbiologically confirmed methicillin-resistant Staphylococcus aureus (MRSA) infection. Because of the infection risk associated with primary joint replacement, a two-stage procedure was planned. In the first stage of surgery, we prepared a personalized spacer using a 3D-printed mold, antibiotic-loaded polymethylmethacrylate (PMMA), and an intramedullary needle. This spacer restored the function of the knee joint and the daily activities of the affected limb, and the infection was effectively eradicated. This spacer was firmly fixed two years after the surgery, and there were no surgical or spacer-related complications. The patient underwent a second stage of surgery to replace a permanent metal mega-prosthesis, and the knee joint functions returned to near normal. CONCLUSIONS: This case report describes limb-salvage surgery following distal femoral resection for periarticular infection. The personalized spacers prepared by a 3D-printed mold can be used in periarticular infection after long bone resection, mega-prosthetic infection, or limb-salvage surgery for temporary joints in small children.

Microbial transformation of curcumol by Cunninghamella blakesleana.

Microbial transformation of curcumol (1) by Cunninghamella blakesleana (AS 3.970) yielded six metabolites. On the basis of spectral data, their structures were elucidated as 14-hydroxy-9E curcumol (2), 10R,14-dihydroxy curcumol (3), 10S,14-epoxy curcumol (4), 10R,14-epoxy curcumol (5), 10S,14-epoxy-7,11-dehydrocurcumol (6), 10R,14-epoxy-7,11-dehydrocurcumol (7), respectively. Among them 2, 3, 6 and 7 are new compounds; 4 and 5, 6 and 7 are two pairs of epimers.

[Determination of furostanol saponins in Bulbus Allii Macroste].

OBJECTIVE: To establish an Ehrlich reaction-colorimetry method for determining furostanol saponins in Bulbus Allii Macroste. METHOD: Based on the coloration reaction between furostanol saponins and p-dimethylaminobenzaldehyde, the UV detection wavelength used was 515 nm, and the optimum conditions were selected on homogeneous design principle. RESULT: The standard curve of macrostemonoside G was linear in the concentration range of 0.1975-0.9880 mg.ml-1. The average recovery was 97.7% (RSD = 3.65%). CONCLUSION: The method is rapid, accurate and easy to operate.