Comparison of solvent extraction and solid-phase extraction for the determination of polychlorinated biphenyls in transformer oil.

Solid-phase extraction (SPE) of nine polychlorinated biphenyls (PCBs) from transformer oil samples was evaluated using octadecyl (CI8)-bonded porous silica. The efficiency of SPE of these PCBs was compared with those obtained by solvent extraction with DMSO and hexane. Average recoveries exceeding 95% for these PCBs were obtained via the SPE method using small cartridges containing 100mg of 40 pm CI8-bonded porous silica. The average recovery by solvent extraction with DMSO and hexane exceeded 83%. It was concluded that the recoveries and precision for the solvent extraction of PCBs were poorer than those for the SPE.

Effectiveness of mitomycin C in reducing reformation of adhesions following surgery for restrictive strabismus.

PURPOSE: To evaluate the efficacy of mitomycin C in reducing reformation of adhesions following surgery for restrictive strabismus. METHODS: Sixteen patients with restrictive strabismus resulting from trauma, retinal detachment surgery, and multiple squint surgeries were randomized to either a mitomycin group (8 patients) or a control group (8 patients). Mitomycin C (0.2 mg/mL) was applied intraoperatively for 5 minutes after release of adhesions. Range of passive ductions was scored for comparison. Postoperative follow-up ranged from 3-18 months. RESULTS: Compared to controls, the mitomycin C group had better range of passive ductions. There were no complications related to the cornea, intraocular pressure, uveitis, or muscle disinsertion in the mitomycin C group. CONCLUSION: Intraoperative application of mitomycin C (0.2 mg/mL for 5 minutes) is a safe and effective adjunct to surgery in the treatment of restrictive strabismus.