NanoSIMS Analysis of Rare Earth Elements in Silicate Glass and Zircon: Implications for Partition Coefficients.

We have developed a method to analyze all rare earth elements in silicate glasses and zircon minerals using a high lateral resolution secondary ion mass spectrometer (NanoSIMS). A 2nA O- primary beam was used to sputter a 7-8-µm diameter crater on the sample surface, and secondary positive ions were extracted for mass analysis using an accelerating voltage of 8 kV. A high mass resolving power of 9,400 at 10% peak height was attained to separate heavy REE from oxide of light REE. A multi-collector system combined with peak-jumping by magnetic field was adjusted to detect REEs and silicon-30 for calibration. Based on results of NIST SRM610 glass, sensitivities of REEs vary from 3 cps/ppm/nA of Lu to 13 cps/ppm/nA of Eu. Reproducibility of REE/Si ratios is better than 18% at 2σ. Secondary ion yields of REEs show positive relationships with their ionization potential of second valence. REEs of AS3, QGNG, and Torihama zircons were measured and calibrated against those of 91500 standard zircon. SIYs of REEs of zircon are identical to those of the glass standard. AS3 and QGNG data are generally consistent with those of previous work. Torihama REE data combined with the whole rock data provide partition coefficients of REEs between silicate melt and zircon. The relationship between these coefficients and ionic radius is explained by an elastic moduli model.

One-year results of anti-vascular endothelial growth factor therapy combined with triamcinolone acetonide for macular edema associated with branch retinal vein occlusion.

PURPOSE: To compare anti-vascular endothelial growth factor (anti-VEGF) monotherapy with anti-VEGF therapy combined with sub-Tenon's capsule injections of triamcinolone acetonide (STTA) in patients with macular edema (ME) associated with branch retinal vein occlusion (BRVO). STUDY DESIGN: Retrospective observational study METHODS: This study included 186 eyes: 138 eyes received intravitreal injection of ranibizumab (IVR), and the remaining 48 eyes received IVR combined with STTA therapy. If additional IVR were necessary, STTA were performed simultaneously. RESULTS: Both groups showed a rapid reduction in ME. The changes in logMAR visual acuity (VA) from baseline to 12 months were - 0.26 ± 0.26 in the IVR and - 0.20 ± 0.26 in the IVR with STTA groups (P = 0.209). The changes in mean central foveal thickness from baseline to 12 months were - 226.9 ± 208.2 µm in the IVR and - 236.0 ± 214.0 µm in the IVR with STTA groups (P = 0.798). The required number of IVR was 3.4 ± 1.9 in the IVR group, and 3.4 ± 1.6 in the IVR and STTA group (P = 0.950). There were no significant differences in any parameters between the two groups. CONCLUSION: There were no clear differences between combination therapy of anti-VEGF with STTA and anti-VEGF monotherapy for the treatment of patients with ME associated with BRVO. The number of anti-VEGF injections in patients who received the combination therapy was not reduced as compared with the number of anti-VEGF injections in patients who received the monotherapy.