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A new mode of polymerization of glycidyl acetate (1a) to yield a poly(ortho ester), i.e., poly-[(2-methyl-1,3-dioxolane-4,2-diyl)oxymethylene] (3a), was explored. This new polymerization exclusively proceeded when a bulky Lewis acid, methylaluminium bis(2,6-di-tert-butyl-4-methylphenoxide) (2a), was employed as the catalyst. The polymerization of 1a with 4 mol % of 2a proceeded smoothly in toluene at 0°C and gave 3a in 82% after 1 h. The time-trace of the polymerization system revealed that this polymerization was completed within 3 min under these conditions. The polymerization mechanism is tentatively assumed as polyaddition of zwitterionic species produced from 1a with the assistance of 2a.The polymerization of glycidyl methacrylate (1b) with 2a gave poly(ortho ester) 3b in a similar manner.

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Patients with end-stage kidney disease (ESKD) are at higher risk for rhabdomyolysis induced by statin than patients with normal kidney function. Previously, we showed that this increase in the severity of statin-induced rhabdomyolysis was partly due to uremic toxins. However, changes in the quantity of various trace elements in ESKD patients likely contribute as well. The purpose of this study is to determine the effect of trace elements on statin-induced toxicity in rhabdomyosarcoma cells exposed to uremic serum (US cells) for a long time. Cell viability, apoptosis, mRNA expression, and intracellular trace elements were assessed by viability assays, flow cytometry, real-time RT-PCR, and ICP-MS, respectively. US cells exhibited greater simvastatin-induced cytotoxicity than cells long-time exposed with normal serum (NS cells) (non-overlapping 95% confidence intervals). Intracellular levels of Mg, Mn, Cu, and Zn were significantly less in US cells compared to that in NS cells (p < 0.05 or 0.01). Pre-treatment with TPEN increased simvastatin-induced cytotoxicity and eliminated the distinction between both cells of simvastatin-induced cytotoxicity. These results suggest that Zn deficiencies may be involved in the increased risk for muscle complaints in ESKD patients. In conclusion, the increased severity of statin-induced rhabdomyolysis in ESKD patients may be partly due to trace elements deficiencies.

No abstract