We analyzed the expression of 15 cancer/testis and four melanoma differentiation antigens in 21 metastatic melanoma cell lines using reverse transcriptase-polymerase chain reaction (RT-PCR) assay. On the basis of morphological characteristics, tumor cell lines were divided into three groups with high, moderate, and low grade of differentiation. Evaluation of gene expression and melanoma cell morphology has revealed a correlation between increased expression of cancer/testis genes and differentiation grade of cancer cells. The gene expression pattern for lymph node metastases and primary tumors exhibits the distribution of expression level and frequency similar to that found for established cell lines. Nevertheless, only 60% lymph node metastases or primary tumor tissue of randomly selected patients show marked expression of the most prominent cancer/testis genes, and almost 90% lesion tissue expresses at least one of 15 cancer/testis genes.

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The spatial and frequency characteristics of cortical electrical activity were studied in healthy human subjects in two series of experiments involving solution of sequentially presented visual tasks. The first task was to assess the relative sizes of two circles and was identical in both series. In the first series, this was supplemented by a task consisting of recognition of pseudowords/words, presumptively also requiring predominant involvement of the ventral "what?" visual system. In the second series, the additional task (spatial localization of a target stimulus in a matrix of letters) was associated with the predominant involvement of the dorsal "where?" visual system. Cortical electrical activity immediately before presentation of pairs of tasks was analyzed. Measures of EEG spectral power in the frontal, central, occipital, and temporal areas of the cortex was subjected to dispersion analysis. The power of electrical potentials in the delta and beta1 frequency ranges was greater when both tasks were associated predominantly with activation of the ventral visual system (first series of experiments). Power in the occipital alpha rhythm was lesser in the left hemisphere in both series of experiments. The interaction of the "experimental series" and "hemisphere" factors was significant in the temporal areas for EEG activity in the alpha2 range, where the predominant involvement of the ventral visual system on solution of both tasks corresponded to greater asymmetry in the electrical oscillations in the rapid alpha2 rhythm and its neighboring beta1 range with greater desynchronization (lesser power) on the left side. Thus, the nature of the ongoing activity is reflected in the spatial-frequency characteristics of the "background" electrical activity of the cortex.

The coherence functions of cortical electrical potentials were studied in 35 healthy adults in the alpha (8-13 Hz) and beta (14-25 Hz) ranges, recorded at the stages of formation and testing of a visual set to images of faces bearing different emotional expressions. At the set actualization stage, the frontal area showed significant increases in intra-and interhemisphere coherence of potentials in the alpha range and coherence of potentials between the frontal and temporal areas of the cortex in the right hemisphere. These analytical results support the suggestion that the formation and actualization of a set to emotional facial expression are predominantly associated with activity in the frontal areas of the cortex. This conclusion is based on the view that the extent of spatial synchronization of electrical potentials is a measure of the functional relationships between corresponding cortical areas and their cooperativity, and thus reflects the state of their activity.

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