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New laser methods have introduced new possibilities and partly replaced traditional methods in corneal surgery. Femtosecond lasers have traditionally been used to replace the surgeons' knife in corneal refractive surgery and corneal transplantation. Excimer laser has been used from the beginning of 1990 for the reshaping of cornea. With the development of excimer laser, traditional photorefractive corneal surgery has improved and new methods have been found such as PRK, PTK, epi-LASIK, and LASEK. Today LASIK, the most commonly used refractive surgery, uses both femtosecond and excimer lasers. SMILE, the most recent method in corneal refractive surgery, is solely based on the use of femtosecond laser.

Podocyte-specific expression of a novel trans -Golgi protein Vear in human kidney . Background Vear is a recently identified Golgi apparatus-associated protein. It has been suggested to be involved in vesicular trafficking between the Golgi and the vacuolar/lysosomal system. Proteins similar to Vear have also been shown to interact with activated ARF proteins ( A DP r ibosylation f actor), and they are probably involved in membrane trafficking from the trans -Golgi network (TGN). We have previously shown that Vear is widely distributed in human tissues, with an especially high level of mRNA in the kidney. This study further characterizes the distribution and subcellular localization of Vear in normal adult kidney and shows its association with glomerulogenesis in fetal kidney. Methods Immunofluorescence and immunoelectron microscopy were used to study the expression of Vear in fetal and adult kidney. The expression of Vear in isolated glomeruli was shown by immunoblotting. The distribution of its mRNA was analyzed by using in situ and Northern hybridization. Results In situ hybridization and immunofluorescence microscopy showed that in the kidney, Vear is present in glomerular structures. By fluorescence microscopy, the immunoreactivity for Vear was found only in podocytes, as judged by its distinct colocalization with podocalyxin and vimentin, well-established marker proteins of podocytes. Its specific expression in the glomeruli versus other compartments of the kidney was also verified by Western blotting. By using immunogold electron microscopy, Vear was seen in the Golgi apparatus, tubulovesicular structures, and membranes adjacent to the Golgi complex. In fetal kidney, expression of Vear coincided with the formation of segmental structures of the glomeruli. It was first seen close to the undifferentiated luminal cells at the vesicular stage and increasingly in the differentiating podocytes at the more advanced stages of glomerulogenesis. Conclusions In the kidney, Vear shows a distinct, specific, and developmentally regulated expression in glomerular podocytes. This suggests that Vear has a specific function in podocytes. It could be associated with the known high secretory and synthetic activity of the podocytes, especially the production of the basement membrane components, which are critically involved in the glomerulogenesis and the maintenance of the glomerular function.

The relationship between glutathione deficiency, glycogen metabolism and ascorbate synthesis was investigated in isolated murine hepatocytes. Glutathione deficiency caused by various agents increased ascorbate synthesis with a stimulation of glycogen breakdown. Increased ascorbate synthesis from UDP-glucose or gulonolactone could not be further affected by glutathione depletion. Fructose prevented the stimulated glycogenolysis and ascorbate synthesis caused by glutathione consumption. Reduction of oxidised glutathione by dithiothreitol decreased the elevated glycogenolysis and ascorbate synthesis in diamide or menadione treated hepatocytes. Our results suggest that a change in GSH/GSSG ratio seems to be a sufficient precondition of altering glycogenolysis and a consequent ascorbate synthesis.

The GGAs are a multidomain protein family implicated in protein trafficking between the Golgi and endosomes. Here, the VHS domain of GGA2 was shown to bind to the acidic cluster–dileucine motif in the cytoplasmic tail of the cation-independent mannose 6-phosphate receptor (CI-MPR). Receptors with mutations in this motif were defective in lysosomal enzyme sorting. The hinge domain of GGA2 bound clathrin, suggesting that GGA2 could be a link between cargo molecules and clathrin-coated vesicle assembly. Thus, GGA2 binding to the CI-MPR is important for lysosomal enzyme targeting.

Vear is a novel Golgi-associated protein with a domain structure characteristic of many vesicular transport-associated proteins. It has been suggested that Vear is involved in vesicle transport through trans-Golgi. In this study, we have determined the localization of Vear in skeletal muscle. The staining for Vear in normal human muscle revealed a distribution pattern similar to that of type I fibers. We conclude that Vear is preferentially expressed in type I fibers in human muscle, presumably indicative of a specific function that remains to be identified.

The VHS (Vps-27, Hrs and STAM) domain is a 140 residue long domain present in the very NH2-terminus of at least 60 proteins. Based on their functional characteristics and on recent data on the involvement of VHS in cargo recognition in trans-Golgi, VHS domains are considered to have a general membrane targeting/cargo recognition role in vesicular trafficking. Structurally, VHS is a right-handed superhelix of eight helices with charged surface patches probably serving as sites of protein–protein recognition and docking.