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Aims/hypothesis: The present study aimed to investigate the expression levels of and the relationship between 14-3-3 ζ and protein kinase C (PKC) in the retina of early diabetes. Methods: Changes in the expression levels of, and interaction between, 14-3-3 ζ and PKC were investigated by Northern and Western blot analyses, immunoprecipitation and double immunostaining in the retina of diabetic rats after 6 weeks of diabetes. PKC activity was examined using a PKC assay. Results: In the diabetic retina, the molecular levels of 14-3-3 ζ were reduced, while those of PKC β and ζ were increased. Direct interaction between 14-3-3 ζ and PKC was markedly decreased in the retina after 6 weeks of diabetes, while PKC activity was increased. Conclusions/interpretation: These findings show that a reduction in 14-3-3 ζ can induce PKC activation, suggesting that this is a main cause of visual dysfunction in the retina during diabetes.

In situ high-pressure x-ray-di8'raction studies have been carried out on T1Re04 up to 14.5 GPa at room temperature using a diamond-anvil cell. The x-ray data show that the orthorhombic D2I, TlRe04 (I) transforms to another closely related orthorhombic phase, T1Re04 (I') around 1.0 GPa, then to a wolframite-related monoclinic phase T1Re04 (II) near 2.0 GPa, and finally to a BaWO4 (II)-related monoclinic phase TlRe04 (III) at about 10 GPa. The volume change at the first transition is negligible, and about 2% and 9%%uo, respectively, at the two subsequent transitions. The results suggest a very minor change in structure at the first transition. The 2% 6 Vat the second transition is consistent with the proposed structural arrangement from pseudoscheelite phase (I') to the wolframite phase (II). The large 6 V at the third transition is attributed to a change to a truly octahedral coordination for Re with respect to oxygens. All the three high-pressure phases of T1Re04 are unquenchable and revert back to the lowpressure orthorhombic phase (I) on release of pressure. The results are in very good agreement with those obtained in a previous high-pressure Raman study up to 15 GPa. From pressure-volume data, we obtain a value of 26 GPa for the bulk modulus Ko of phases {I)and (I'). The bulk moduli of phases (II) and (III) have been calculated as 45.6 and 47.6 GPa, respectively.

Aims/hypothesis The study aimed to evaluate the efficacy of recombinant adenovirus expressing αA-crystallin (Ad-αAc-Gfp) in reducing pericyte loss within retinal vasculature in early diabetes. Methods Diabetes was induced by streptozotocin injection into C57BL/6 mice. Ad-αAc-Gfp was delivered by intravitreous injection to the right eyes of mice 2 weeks before induction of diabetes. Vascular leakage was determined by fluorescent angiography, Evans Blue leakage assay and leucocyte adhesion test. Production of αA-crystallin was analysed by immunoblotting and double immunostaining and pericyte loss was analysed by pericyte count. Results Vessel leakage and pericyte loss were observed in the streptozotocin-induced diabetic retina. Decreased abundance of αA-crystallin in retinas 2 and 6 months after the induction of diabetes was confirmed by two-dimensional electrophoretic analysis, immunoblotting and RT-PCR. Double immunofluorescence staining for αA-crystallin and NG2 chondroitin sulphate proteoglycan revealed that αA-crystallin was predominantly produced in the retinal pericyte and that the number of αA-crystallin-producing pericytes decreased in the diabetic retina. Retinal infection with Ad-αAc-Gfp led to decreased pericyte loss and vascular leakage compared with control. Conclusions/interpretation Intravitreal delivery of Ad-αAc-Gfp protects against vascular leakage in the streptozotocininduced model of diabetes. This effect is associated with the inhibition of diabetic retinal pericyte loss in early diabetes, suggesting that αA-crystallin has a role in preventing the pathogenesis of early diabetic retinopathy.