[Lymphangiomatous hyperplasia with eosinophilia; Kimura's disease (author's transl)]. / L'hyperplasie angio-lymphoïde avec hyperéosinophilie dite maladie de Kimura. A propos d'une localisation palpébrale.

Kimura's disease is a benign affection of young people in which there are non-specific subcutaneous nodules, mainly found in the region of the head. They can be identified by their particular histological appearance which includes vascular and inflammatory components, and by local and sometimes blood eosinophilia. The etiology is not known but could be allergic in nature.

Vitreous replacement.

The long list of substances used by ophthalmologists for vitreous replacement can be reduced to only three for four. Their use depends upon the surgical procedure. After trauma or cataract extraction and in vitreous surgery, saline is the best substitute; it is rapidly replaced by aqueous humour and no inflammatory reaction occurs. Retinal detachment surgery requires a highly viscous material, harmless to ocular tissues, and these criteria are met by Healon H. Whenever highly viscous hyaluronic acid is available, it should be used instead of saline or air (Regnault and Brégeat, 1973). Sulphahexafluoride gas has also been used to treat these difficult cases of retinal detachment but further experience is needed before a definite conclusion can be reached.

[Preventive treatment of retinal detachment in aphakic eyes]. / Traitement préventif du décollement de la rétine dans les yeux aphaques.

We have examined 243 cases with retinal detachment occurring within 6 months following cataract surgery. In 92 of them retinal tear was due to lattice degeneration, in 66 to snail track degeneration and in 17 to equatorial degeneration. 290 other patients had preventive treatments. In this group, there were only 10 cases of retinal detachment. 9 out of 22 patients who had no preventive treatment suffered retinal detachments. There are two reasons for the occurrence of this retinal detachment in the 6 months following cataract surgery in eyes where retinal degenerations are found: (1) surgical trauma even with cryoextraction is responsible for traction of the vitreous base, (2) rapid disappearance of the hyaluronic acid in the aphakic vitreous is responsible for the degradation of the vitreous with formation of large zones of liquid vitreous. When adhesion between the vitreous and the retinal degeneration area remains, the traction is responsible for retinal tear or retinal detachment. The importance of the preventive treatment of retinal lesions prior to cataract surgery should be stressed.

Diabetic microangiopathy: renal and retinal aspects.

Diabetic microangiopathy is a degenerative process specific to diabetes. Metabolic theory holds that the metabolic defect predisposes to vascular abnormalities, but other theory suggests that microangiopathy and metabolic disorders are of different origin. Metabolic and ultrastructural modifications in kidney and retina are reviewed. Human and animal studies suggest a specific organ response to fortuitous association of several factors leading to microvascular disease.

Biochemical and ultrastructural study of human diabetic conjunctiva.

Combined biochemical and ultrastructural study of conjunctival biopsies of 27 normal subjects and 45 diabetics (40 to 60 years old) was made. The "in vitro" incorporation of 14C-glucosamine and 3H-proline in freshly excised conjunctival biopsies was studied. The alterations of the capillary basement membrane of the conjunctiva were studied by electron microscopy. The following results were obtained: 1) A decrease of the specific activity of 14C-glucosmaine incorporation was found in fractions of diabetic conjunctiva. 2) In diabetic conjunctiva the percentages of 3H-proline incorporation in polymeric collagen containing fraction and structural glycoproteins containing fraction were significantly increased with a parallel decrease of 3H-proline incorporation in "crude soluble collagen" fraction expressed as a percentage of total incorporation. 3) Significant thickening of capillary basement membrane was observed with the appearance of collagen-like fibrils within the basement membrane in diabetic conjunctiva. Such fibrils were not seen in normal basement membranes. A relation between the extent of basement membrane thickening and the appearance of collagen-like fibrils is suggested. 4) The higher percentage of incorporation of 3H-proline in polymeric collagen may be related to the appearance of collagen fibrils in thickened basement membranes of the diabetic conjunctival capillaries. 5) These results suggest an abnormal regulation of the relative rate of biosynthesis and/or excretion of intercellular matrix macromolecules (collagen, structural glycoproteins) as part of the metabolic disorders characterising diabetes.

In vitro study of gamma-glutamyl transpeptidase in rat lens.

gamma-Glutamyl transpeptidase catalyzes the initial step in the utilization of glutathione. In the lens, this enzyme is accessible to externally supplied substrates. An efflux of glutathione from the lens occurs when it was incubated in saline. Inhibition of gamma-glutamyl-transpeptidase by L-serine-borate decreases the rate of glutathione breakdown in the external medium and the rate of its decline in the lens.

Modification of human platelet behaviour in diabetes.

Among the different factors which could be responsible for the retinal vascular disturbances in diabetic retinopathy, we have investigated platelet populations, sialic acid content of platelets and collagen-induced platelet aggregation. The following results were obtained: a) there was no modification of platelet population distribution except for population A; b) there was a modification of collagen-induced platelet aggregation; the lag time was increased in diabetics.

Prevention of experimental obstructions in the retinal microcirculation. Arterial Fluorescein Studies.

Platelet aggregates were formed in flowing blood by infusing ADP in the carotid artery of the dog. Under fluorographic examination, these aggregates were seen to lodge in retina vessels. Previous administration of gliclazide helped maintain normal retina circulation.

Interaction of bovine epithelial lens (BEL) cells with extracellular matrix (ECM) and eye-derived growth factor (EDGF). II. Partial re-expression of the differentiated collagen distribution and phenotype.

The differentiated phenotype of bovine epithelial lens (BEL) cells consists primarily of type IV collagen production with homogeneous cellular form and monolayer organization. We have previously described how, after several subcultures, BEL cells lost this phenotype, which was replaced by a complex collagen mixture consisting predominantly of type I and type III collagens and a minor proportion of type IV collagen. The cells became irregular and formed multilayers. These dedifferentiated cells can re-express their initial morphological properties when subcultured on an extracellular matrix (ECM) in presence of an eye-derived growth factor (EDGF), as described in the first paper of this series [30]. Furthermore, those cells passaged only one time on ECM + EDGF partially re-express the native differentiated collagen phenotype. The cells synthesize a majority of type IV collagen (up to 65%) with minor amounts of interstitial collagens. As in early subcultured cells, the major proportion of total collagen accumulated in the cell layer. Taken together, the morphological and biochemical data emphasize the relationship between cell shape and collagen phenotype expression. They also provide a reversible system for the study of normal gene expression and pathological alterations.

Evidence of leukotriene B4 biosynthesis in epithelial lens cells.

Metabolism of sodium (14C)-arachidonate by bovine epithelial lens cells was studied in culture. The cells converted arachidonic acid into a major product whose formation was not inhibited by aspirin, a cyclo-oxygenase inhibitor, but was suppressed by nordihydroguaiaretic acid, a lipoxygenase inhibitor and by dexamethasone. This metabolite co-migrated with leukotriene B4 in thin layer chromatography and high pressure liquid chromatography. These data represent the first evidence for a lipoxygenase product in the lens. LTB4 could play an important role in the physiopathology of this organ.