Activation of Multimodal Areas in the Human Cerebral Cortex in Response to Biological Motion Sounds

Functional magnetic resonance imaging (fMRI) was used to investigate activation of the multimodal areas in the cerebral cortex–supramarginal and angular gyri, precuneus, and middle temporal visual cortex (MT/V5)–in response to motion of biologically significant sounds (human footsteps). The subjects listened to approaching or receding footstep sounds during 45 s, and such stimulation was supposed to evoke auditory adaptation to biological motion. Listening conditions alternated with stimulation-free control. To reveal activity in the regions of interest, the periods before and during stimulation were compared. Most stable and voluminous activation was detected in the supramarginal and angular gyri, being registered for all footstep sound types–approaching, receding and steps in place. Listening to human approaching steps activated the precuneus area, with the volume of activation clusters varying considerably between subjects. In the MT/V5 area, activation was revealed in 5 of 21 subjects. The involvement of the tested multimodal cortical areas in analyzing biological motion is discussed.     

Lipid second messengers and cell signaling in vascular wall

Agonists of cellular receptors, such as receptor tyrosine kinases, G protein-coupled receptors, cytokine receptors, etc., activate phospholipases (C(gamma), C(beta), A(2), D), sphingomyelinase, and phosphatidylinositol-3-kinase. This produces active lipid metabolites, some of which are second messengers: inositol trisphosphate, diacylglycerides, ceramide, and phosphatidylinositol 3,4,5-trisphosphate. These universal mechanisms are involved in signal transduction to maintain blood vessel functions: regulation of vasodilation and vasoconstriction, mechanical stress resistance, and anticoagulant properties of the vessel lumen surface. Different signaling pathways realized through lipid second messengers interact to one another and modulate intracellular events. In early stages of atherogenesis, namely, accumulation of low density lipoproteins in the vascular wall, cascades of pro-atherogenic signal transduction are triggered through lipid second messengers. This leads to atherosclerosis, the general immuno-inflammatory disease of the vascular system.     

A novel 45 kDa secretory protein from rat olfactory epithelium: primary structure and localisation.

cDNA clones encoding the 45 kDa protein were isolated from a rat olfactory epithelium cDNA library and their inserts were sequenced. The reconstructed protein sequence comprises 400 amino acids with a calculated molecular mass of 46,026 Da. A homology was revealed between the amino acid sequence of the 45 kDa protein and the proteins involved in the transfer of hydrophobic ligands. Using in situ hybridisation, the 45 kDa protein mRNA expression was detected in the layer of supportive cells of olfactory epithelium, apical region of trachea, surface layer of the ciliated bronchial epithelium in lung and in skin epidermis.     

RdgC/PP5-related phosphatases: novel components in signal transduction.

A great variety of cellular functions are regulated by protein serine/threonine phosphatases (PP). This review summarises the current knowledge of the structural features, patterns of expression and involvement in signal transduction pathways of protein serine/threonine phosphatases related to PP5 and RdgC. Designated now as PP5/RdgC subfamily by P. T. W. Cohen in her 1997 study published in Trends in Biochemical Sciences, (Vol. 22, pp. 245-251), this heterogeneous group comprises phosphatases PP5/PPT, containing regulatory domains with tetratricopeptide repeats, RdgC/PPEF, which possess Ca2+-binding EF hand-type sites, and, recently discovered in plants, PP7. PP5 is ubiquitously expressed and appears to be a multifunctional phosphatase involved in a number of different signalling pathways. In contrast, expression of RdgC/PPEF phosphatases and PP7 is confined primarily to specialised sensory cells in animals and plants, respectively, which may be indicative of their more specialised roles in sensory signal transduction.     

Understanding weakly coordinating anions: tetrakis(pentafluorophenyl)borate paired with inorganic and organic cations

Efficient design of ionic compounds requires a systematic understanding of cation–anion interactions. Weakening of electrostatic attraction is essential to increase the liquid range of the ionic compound and decrease its melting point. Here, we report simulations of the closest-approach cation–anion distances in a variety of ion pairs containing the tetrakis(pentafluorophenyl)borate (TFPB^–) anion. Small alkali cations (Li⁺, Na⁺) penetrate the TFPB^– core, whereas K⁺ and larger organic cations do not. In the latter case, the shortest possible distance from the cations to the boron atom of TFPB^– ranges from 0.50 nm to 0.63 nm. TFPB^– was shown to be substantially rigid, providing a steric hindrance to thermodynamically efficient cation–anion coordination. Our results prove that TFPB^– is more efficient for electrostatic charge confinement than the tetraoctylammonium cation, whereas the perfluorophenyl group is more efficient than linear alkyl chains. These simulations will motivate development of TFPB^–-based ionic liquids with low phase transition points.

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Graphical Abstract Ionic configuration of the equilibrated “TFPB + K”system

     

Content of total free nucleotides in the plankton of the Rybinsk reservoir (Upper Volga)

The content of total free nucleotides (TFNs) in the plankton of the Rybinsk reservoir and in specific size fractions of the plankton has been determined by the spectrophotometric method modified by the authors. The content of TFNs amounts to 58.1 ± 5.4, 75.2 ± 4.6, and 64.1 ± 7.3 μg/L in spring, summer, and autumn, respectively, and exhibits a close correlation with the total plankton biomass (r = 0.67), whereas the TFN/Chl parameter is closely correlated to the ratio of autotroph and heterotroph organism biomass (r = 0.96). The contribution of the fraction of more than 3 μm in size (microplankton and nanoplankton) to the TFN pool is 77 ± 4% in spring, 74 ± 3% in summer, and 47 ± 3% in autumn, whereas the contribution of the fraction of 0.45–3 μm in size (ultraplankton) during these seasons is 23 ± 4, 26 ± 3, and 53 ± 3%, respectively. Regression equations that can be used to infer an estimate of plankton biomass from TFN content have been proposed.