Modification of Oligopeptides Increasing the Effectiveness of Their Interaction with Interleukin-8 in Human Blood Plasma

Russian Journal of Bioorganic Chemistry - Molecular modeling, which identified several peptide sequences, was carried out in search for compounds capable of reducing the interleukin-8 concentration...     

Mimetics of the Arg-Gly-Asp Sequence: Synthesis and Studies of the Antiaggregative Properties

Russian Journal of Bioorganic Chemistry - It is known that the Arg-Gly-Asp sequence in the fibrinogen molecule is key in binding to the receptors on the surface of platelets. We searched for the...     

Hypoxia as pathogenic factor affecting the eye tissues: The selective apoptotic damage of the conjunctiva and anterior epithelium of the cornea

The effect of acute hypoxia on the occurrence of apoptosis in eye cells in rats placed in a pressure chamber was studied. Selective primary lesion of cells of the conjunctiva and the anterior corneal epithelium was found. A possible role of the simulated hypoxic conditions in the dry eye syndrome pathogenesis, which is accompanied by primary lesion of cells in the anterior eye surface tissues is discussed.     

The Effect of <Emphasis Type="Italic">para</Emphasis>-Aminobenzoic Acid on Apoptosis Processes in the Adult Rat Conjunctiva and Corneal Epithelium in vivo after Hypobaric Hypoxia

The initial stages of apoptotic damage to the conjunctiva and corneal epithelium, in the renewing cell populations of the eye has been studied in adult rats exposed to acute hypobaric hypoxia in vivo, and the effect of para-aminobenzoic acid (PABA) administered as the Aktipol pharmaceutical preparation (0.007% PABA) has been assessed in this experimental setup. Apoptotic damage to cell DNA was aggravated after two instances of hypoxia, and this change was accompanied by an increase in the intensity of the regenerative process inferred from the expression levels of phosphorylated histone pH3, a mitotic cell marker, and phosphorylated histone γ-H2AX, a DNA repair marker. Parabulbar injection of Aktipol 24 h before hypoxia has been shown to block development of the apoptotic process and to maintain a physiologically normal level of apoptosis, and thus the preparation exerted a protective effect in hypoxia.     

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.     

Adaptation mechanisms of respiratory blood function in Teleostei

Analysis of osmotic resistance of erythrocytes identified the similarity between marine and freshwater Teleostei and inclination of erythrocytes from freshwater fish to intravascular haemolysis. Structural resistance of hemoglobin was significantly higher in marine species and resistance to dehydration was significantly higher in freshwater fish. The resistance of erythrocytes and hemoglobin in freshwater fish widely varyies depending on species’ inhabitation conditions. Several strategies for stabilization of respiratory function in the blood of Teleostei were formulated as following: (1) a strategy of compensatory type in the fish ontogenesis, (2) formation of different quality resistance to haemolysis of young and mature erythrocytes; (3) variability resistance of hemoglobin to dehydration and (4) transformation of homeostasis of an organism in extreme conditions.