Two new Ca indicators, purpurate-3,3'diacetic acid (PDAA) and 1,1'-dimethylpurpurate-3,3'diacetic acid (DMPDAA), were synthesized and used to measure Ca transients in frog cut muscle fibers. These indicators are analogues of the purpurate components of murexide and tetramethylmurexide, in which two acetate groups have been incorporated into each molecule to render it membrane impermeant. The apparent dissociation constant for Ca is 0.95 mM for PDAA and 0.78 mM for DMPDAA. One of the indicators was introduced into a cut fiber, which was mounted in a double Vaseline-gap chamber, by diffusion from the endpool solutions. The time course of indicator concentration, monitored optically in the middle of the fiber in the central-pool region, suggests that 19% of the PDAA or 27% of the DMPDAA became bound or sequestered inside the fiber. In resting fibers, the absorbance spectrum of either indicator was well fitted by the indicator's [Ca] = 0 mM cuvette absorbance spectrum, which is consistent with the idea that PDAA and DMPDAA do not enter the sarcoplasmic reticulum as tetramethylmurexide appears to be able to do (Maylie, J., M. Irving, N.L. Sizto, G.Boyarsky, and W. K. Chandler. 1987. Journal of General Physiology. 89:145-176).After an action potential, the absorbance of either indicator underwent a rapid and transient change that returned to the prestimulus baseline within 100-200 ms. The amplitude of this change had a wavelength dependence that matched the indicator's Ca-difference spectrum. The average amplitude of peak free [Ca] was 21 #M (PDAA or DMPDAA) if all the indicator inside a fiber was able to react with Ca as in cuvette calibrations, and was 26 (PDAA) or 28/zM (DMPDAA) if only freely diffusible indicator could so react. These results suggest that PDAA and DMPDAA are the first Ca indicators that provide a reliable estimate of both the amplitude and time course of (the spatial average of) free [Ca] in a twitch muscle fiber after an action potential.

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Purpose: To compare the incidence of re-orientating surgery to improve misalignment of three models of acrylic toric intraocular lenses: AcrySof toric intraocular lens (Alcon Laboratories, Inc.), TECNIS toric intraocular lens (Johnson & Johnson Vision, Inc.) and HOYA 355 toric intraocular lens (HOYA). Methods: In this retrospective, multicenter case series, medical charts were reviewed for collecting data on realignment surgery of toric intraocular lenses at 10 ophthalmic surgical sites in Japan. Results: Over all, intraocular lens repositioning surgery was conducted in 89 of 9430 eyes (0.944%) at an average of 10.5 ± 9.7 days after the initial cataract surgery. The incidence was 0.213% (11/5155), 1.797% (62/3451) and 1.942% (16/824) with AcrySof, TECNIS and HOYA toric intraocular lenses, respectively. The incidence was significantly lower with AcrySof than with other two brands of toric intraocular lenses ( p < 0.0001). In those eyes which underwent reorientation surgery, the amount of misalignment was 26.4 ± 21.9°, 29.7 ± 15.4° and 28.1 ± 20.7° with AcrySof, TECNIS and HOYA toric intraocular lenses, respectively; there was no significant difference among groups ( p = 0.821). The repositioning surgery significantly reduced misalignment in all three groups. Conclusion: The rotational stability was considerably different among toric intraocular lenses of different manufacturers. The incidence of repositioning surgery was significantly lower with AcrySof than with TECNIS and HOYA toric intraocular lenses.

We prospectively surveyed the incidence of retinal vein occlusion (RVO) at the glaucoma clinic of Hiroshima University between 1986 and 1991. Among 433 glaucoma patients, 18 (4.2%) subsequently presented with RVO, 9 had central retinal vein occlusion (CRVO) and 9 exhibited branch retinal vein occlusion (BRVO). Seven of 87 (8.1%) patients with primary angle closure glaucoma exhibited RVO, showing the highest incidence among glaucoma types. The incidence of RVO detected by the general outpatient clinic was 0.59% during the same period. The BRVO/CRVO ratio in the glaucoma clinic was 1.0, while it was 4.3 in the general outpatient clinic. Glaucoma is an important risk factor for the development of RVO, especially CRVO.

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