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The paper gives the results of electroretinography (ERG) in 38 patients (73 eyes) with type 2 diabetes mellitus at different stages of diabetic retinopathy (including in diabetic macular edema). The reductions in the macular ERG (M-ERG) amplitude parameters and in the retinal density of bioelectrical activity and the decreased amplitude and longer latency of multifocal ERG (mfERG) N1 and P1 components evidence the involvement of the retinal macular region into the pathological process and the magnitude of these changes depends on the presence of imaged macular edema. Despite the certain limitations of mfERG, assessment of the topography of retinal bioelectrical activity in the central field of vision is an important supplement to M-ERG results and may be a prognostic criterion for the development of a pathological process and its extent.

Inactivation of cellular p53 is a crucial step in carcinogenesis. Accordingly, p53 is inactivated in most human cancers by different mechanisms. In cells infected with DNA tumor viruses, p53 is bound to the viral tumor antigens (Tag). The current "dogma" views the Tag-p53 complexes as a way of sequestering and inactivating p53. Using primary human cells and SV40-transformed human cells, we show that in addition to inactivating p53 tumor suppressor activities, the Tag-p53 complex has growth stimulatory activities that are required for malignant cell growth. We found that in human cells, Tag-p53 complexes regulate transcription of the insulin-like growth factor I (IGF-I) gene by binding to the IGF-I promoter together with pRb and p300. Depletion of p53 leads to structural rearrangements of this multiprotein complex, resulting in IGF-I promoter transcriptional repression and growth arrest. Our data provide a novel mechanistic and biological interpretation of the p53-Tag complexes and of DNA tumor virus transformation in general. In the model we propose, p53 is not a passive inactive partner of Tag. Instead the p53-Tag complex promotes malignant cell growth through its ability to activate the IGF-I signaling pathway.

The paper gives the results of electroretinographic and psychophysical studies in hypertensive patients with first-, second-, and third-degree blood pressure (BP) elevation. The most characteristic functional symptoms of hypertensive retinopathy were defined at different stages of its development. There may be impaired retinal bioelectrical activity and diminished contrast and color sensitivity both in the presence and absence of ophthalmoscopically visible changes. Based on the findings, the authors have developed a functional classification of hypertensive retinopathy in relation to the degree of BP elevation.