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Knyazev G.G.,Russian Academy of Medical Sciences
Frontiers in Human Neuroscience | Year: 2013

Self-referential processing has been principally investigated using functional magnetic resonance imaging (fMRI). However, understanding of the brain functioning is not possible without careful comparison of the evidence coming from different methodological domains. This paper aims to review electroencephalographic (EEG) studies of self-referential processing and to evaluate how they correspond, complement, or contradict the existing fMRI evidence. There are potentially two approaches to the study of EEG correlates of self-referential processing. Firstly, because simultaneous registration of EEG and fMRI has become possible, the degree of overlap between these two signals in brain regions related to self-referential processing could be determined. Second and more direct approach would be the study of EEG correlates of self-referential processing per se. In this review, I discuss studies, which employed both these approaches and show that in line with fMRI evidence, EEG correlates of self-referential processing are most frequently found in brain regions overlapping with the default network, particularly in the medial prefrontal cortex. In the time domain, the discrimination of self- and others-related information is mostly associated with the P300 ERP component, but sometimes is observed even earlier. In the frequency domain, different frequency oscillations have been shown to contribute to self-referential processing, with spontaneous self-referential mentation being mostly associated with the alpha frequency band. © 2013 Knyazev. Source

Reshetnyak V.I.,Russian Academy of Medical Sciences
World Journal of Gastroenterology | Year: 2013

This review considers the physiological and molecular biochemical mechanisms of bile formation. The composition of bile and structure of a bile canaliculus, biosynthesis and conjugation of bile acids, bile phospholipids, formation of bile micellar structures, and enterohepatic circulation of bile acids are described. In general, the review focuses on the molecular physiology of the transporting systems of the hepatocyte sinusoidal and apical membranes. Knowledge of physiological and biochemical basis of bile formation has implications for understanding the mechanisms of development of pathological processes, associated with diseases of the liver and biliary tract. © 2013 Baishideng Publishing Group Co., Limited. All rights reserved. Source

Agol V.I.,Russian Academy of Medical Sciences
Trends in Microbiology | Year: 2012

The capacity to injure infected cells is a widespread property of viruses. Usually, this cytopathic effect (CPE) is ascribed to viral hijacking of cellular resources to fulfill viral needs. However, evidence is accumulating that CPE is not necessarily directly coupled to viral reproduction but may largely be due to host defensive and viral antidefensive activities. A major part in this virus-cell interaction appears to be played by a putative host-encoded program with multiple competing branches, leading to necrotic, apoptotic, and, possibly, other types of cell suicide. Manifestations of this program are controlled and modulated by host, viral, and environmental factors. © 2012 Elsevier Ltd. Source

Bazanova O.M.,Russian Academy of Medical Sciences | Vernon D.,Canterbury Christ Church University
Neuroscience and Biobehavioral Reviews | Year: 2014

Exploring EEG alpha oscillations has generated considerable interest, in particular with regards to the role they play in cognitive, psychomotor, psycho-emotional and physiological aspects of human life. However, there is no clearly agreed upon definition of what constitutes 'alpha activity' or which of the many indices should be used to characterize it.To address these issues this review attempts to delineate EEG alpha-activity, its physical, molecular and morphological nature, and examine the following indices: (1) the individual alpha peak frequency; (2) activation magnitude, as measured by alpha amplitude suppression across the individual alpha bandwidth in response to eyes opening, and (3) alpha "auto-rhythmicity" indices: which include intra-spindle amplitude variability, spindle length and steepness.Throughout, the article offers a number of suggestions regarding the mechanism(s) of alpha activity related to inter and intra-individual variability. In addition, it provides some insights into the various psychophysiological indices of alpha activity and highlights their role in optimal functioning and behavior. © 2013 Elsevier Ltd. Source

Lukashev A.N.,Russian Academy of Medical Sciences
Reviews in Medical Virology | Year: 2010

Picornaviruses are small non-enveloped positive strand RNA viruses that can cause a wide range of clinical manifestations in humans and animals. Many of these viruses are highly diversified and globally prevalent. Natural recombination has been reported in most picornavirus genera and is a key genetic feature of these infectious agents. In several socially relevant picornavirus genera, such as enteroviruses, aphthoviruses, parechoviruses and cardioviruses, recombination, combined with dynamic global epidemiology, maintains virus species as a worldwide pool of genetic information. It can be suggested that on a short time scale recombination acts to promote virus diversity, and new recombinant forms of picornaviruses emerge frequently as 'snapshots' of this global pool. On a longer time scale, recombination maintains stability of a gene pool of a species by shuffling sequences and thus limiting divergence and speciation. This review covers existing evidence of recombination in most genera of the family Picornaviridae and possible implications for diagnostics, epidemiology and classification. Copyright © 2010 John Wiley & Sons, Ltd. Source

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