Antioxidants specifically addressed to mitochondria have been studied to determine if they can decelerate senescence of organisms. For this purpose, a project has been established with participation of several research groups from Russia and some other countries. This paper summarizes the first results of the project. A new type of compounds (SkQs) comprising plastoquinone (an antioxidant moiety), a penetrating cation, and a decane or pentane linker has been synthesized. Using planar bilayer phospholipid membrane (BLM), we selected SkQ derivatives with the highest permeability, namely plastoquinonyl-decyl-triphenylphosphonium (SkQ1), plastoquinonyl-decyl-rhodamine 19 (SkQR1), and methylplastoquinonyldecyltriphenylphosphonium (SkQ3). Anti- and prooxidant properties of these substances and also of ubiquinonyl-decyl-triphenylphosphonium (MitoQ) were tested in aqueous solution, detergent micelles, liposomes, BLM, isolated mitochondria, and cell cultures. In mitochondria, micromolar cationic quinone derivatives were found to be prooxidants, but at lower (sub-micromolar) concentrations they displayed antioxidant activity that decreases in the series SkQ1=SkQR1>SkQ3>MitoQ. SkQ1 was reduced by mitochondrial respiratory chain, i.e. it is a rechargeable antioxidant. Nanomolar SkQ1 specifically prevented oxidation of mitochondrial cardiolipin. In cell cultures, SkQR1, a fluorescent SkQ derivative, stained only one type of organelles, namely mitochondria. Extremely low concentrations of SkQ1 or SkQR1 arrested H(2)O(2)-induced apoptosis in human fibroblasts and HeLa cells. Higher concentrations of SkQ are required to block necrosis initiated by reactive oxygen species (ROS). In the fungus Podospora anserina, the crustacean Ceriodaphnia affinis, Drosophila, and mice, SkQ1 prolonged lifespan, being especially effective at early and middle stages of aging. In mammals, the effect of SkQs on aging was accompanied by inhibition of development of such age-related diseases and traits as cataract, retinopathy, glaucoma, balding, canities, osteoporosis, involution of the thymus, hypothermia, torpor, peroxidation of lipids and proteins, etc. SkQ1 manifested a strong therapeutic action on some already pronounced retinopathies, in particular, congenital retinal dysplasia. With drops containing 250 nM SkQ1, vision was restored to 67 of 89 animals (dogs, cats, and horses) that became blind because of a retinopathy. Instillation of SkQ1-containing drops prevented the loss of sight in rabbits with experimental uveitis and restored vision to animals that had already become blind. A favorable effect of the same drops was also achieved in experimental glaucoma in rabbits. Moreover, the SkQ1 pretreatment of rats significantly decreased the H(2)O(2) or ischemia-induced arrhythmia of the isolated heart. SkQs strongly reduced the damaged area in myocardial infarction or stroke and prevented the death of animals from kidney ischemia. In p53(-/-) mice, 5 nmol/kgxday SkQ1 decreased the ROS level in the spleen and inhibited appearance of lymphomas to th...
Patients tolerated the examination well. Comparative analysis of preliminary perimetry results obtained with both methods showed high degree of identity, so the results were concluded to be comparable. By visually isolating the wearer, VR headset achieves elimination of distractions and stable light conditions for visual field testing. The headset-perimeter is compact, mobile, easily transportable, can be used in the work of visiting medical teams and for examination at home.
INTRODUCTION. Recently, posterior vitreous detachment (PVD) was suggested as a fundamental pathologic process in primary angle-closure glaucoma (PACG) in morphologically predisposed patients with anatomically narrow anterior chamber angle.PURPOSE. To study the role of PVD in the development and clinical manifestation of PACG in anatomically predisposed eyes and to assess the capabilities of posterior segment optical coherence tomography (PS-OCT) in PACG diagnostics.MATERIALS AND METHODS. Thirty eyes with newly diagnosed stage I-II PACG and thirty eyes predisposed to PACG (with narrow anterior chamber angle without glaucoma signs) were enrolled in the study. All patients underwent ophthalmological examination, Hyams test, ocular ultrasound (OU) and PS-OCT.RESULTS. PVD with retrohyaloid space (RHS) formation was revealed in all PACG eyes. Positive Hyams test was in 86.67% eyes with PACG, and 13.33% were negative. All the eyes with PVD as a result of Hyams test experienced RHS enhancement correlating with IOP rise. Despite the negative results of Hyams test in some PACG eyes with PVD — glaucomatous optic neuropathy signs were present. Possible causes are discussed.PVD with RHS formation was revealed in 53.33% predisposed to PACG eyes — all with positive result of Hyams test. The other 46.67% eyes predisposed to PACG had negative Hyams test, no PVD and no RHS.CONCLUSION. Obtained results confirm a new theory of PACG etiopathogenesis suggesting PVD with PGS to be the essential mechanism of POAG development in morphologically predisposed eyes. PS-OCT appears to be crucial in PACG early diagnostics.
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