New Carbon-Mineral Sorbent Based on Aluminum Oxide, Polydimethylsiloxane, and Single-Wall Carbon Nanotubes: Assessment of the Effect on Erythrocytes In Vitro.

A comparative study of the effect of a sorbent with nanotubes (Al2O3@ WCNT-PDMS) and a carbon-mineral sorbent (Al2O3@C) on the parameters of human erythrocytes was carried out. Using scanning flow cytometry, the morphological and functional parameters of venous blood erythrocytes as well as drainage blood after its perfusion through columns with sorbents were determined. The compared samples Al2O3@SWCNT-PDMS and Al2O3@C are similar by their effect on the morphological and functional parameters of erythrocytes. The maximum membrane extensibility increased to a greatest extent after contact with Al2O3@C, the amount of hemoglobin in erythrocytes decreased to the greatest extent after perfusion through a column with Al2O3@SWCNT-PDMS sorbent. The scanning flow cytometry is promising for assessing the effect on erythrocytes of new sorption materials intended for blood detoxification. Changes in the parameters of erythrocytes of blood collected in a sterile drainage system for subsequent reinfusion were revealed.

[Nucleus DNA content measurement methods features].

We suggest a new theoretical method of the flow cytometry DNA histograms and apply it for Drosophila melanogaster imaginal discs cells. The model gives a possibility to determine the proportions of cells in G1, G2 (M) and S cell cycle phases. We show that the precision of G1 and G2 (M) DNA content measurements is limited by the precision of device zero signal arrangement. The usage of calculated device zero and dividing cells as the DNA content standards may improve the precision of DNA content measurements. We also compared the precisions of different DNA content methods and draw the conclusion that the current precisions of different methods are similar and lie within 2-6% interval.

Method of estimating preference of the female rat for various sound stimuli while searching for pups.

A rat was placed without her pups in an open T-shaped maze and maternal behavior stimulated by the presentation of pups. The pups were then removed and tone pulses (7 kHz, 14 kHz) and a tape recording of the pup's pain signal were simultaneously presented from different alleys of the maze. Preference was estimated by the predominate direction of sorties during random alternation of the sound sources. Preference for the pup's pain signal was found in eight rats.

[Photomodification of nucleic acids by N-(2-hydroxyethyl)phenazine derivatives of oligonucleotides]. / Fotomodifikatsiia nukleinovykh kislot N-(2-gidroksiétil)fenazinievymi proizvodnymi oligonukleotidov.

Photomodification of a 302-membered single-stranded DNA fragment by 5'-mono- and 3',5'-di-N-(2-oxyethyl)phenazine (Phn) derivatives of oligonucleotides has been investigated. Under strong laser irradiation (lambda 532 nm; power density 2,5 GV/cm2, irradiation dose 30 J) the DNA fragment in the presence of Phn-reagents was significantly destructed (up to 70-95%). The level of complementary addressed modification (24-51%) is a direct function of the length of oligonucleotide address of the photoreagent and the amount of Phn residues, stabilizing the complementary complex. The character of the nonaddressed modification is close to the statistic one, although for a number of photoreagents a rather efficient nonspecific modification of 5'-terminal sequence of target DNA has been detected. Of interest also is an unusually broad positional direction of the DNA fragment photomodification in the area of perfect complementary coupling of 5'-Phn-reagents.

[Laminin-binding protein as a cellular receptor for the equine Venezuelan encephalomyelitis virus: Report 2. Inhibition of replication of equine Venezuelan encephalomyelitis virus by blocking laminin-binding protein on the surface of Vero cells]. / Lamininsviazyvaiushchii belok kak kletochnyi retseptor dlia virusa venesuél'skogo éntsefalomielita loshadei: Soobshchenie. 2. Ingibiriovanie replikatsii virusa venesuél'skogo éntsefalomielita loshchadei putem blokirovaniia lamininsviazyvaiushchego belka na poverkhnosti kletok Vero.

A possible inhibition of the Venezuelan equine encephalomyelitis (VEE) virus replication in Vero cells through the laminin-binding protein (LBP) blocking in the surface of such cells was investigated in order to verify the LBP value. It was demonstrated, on the basis of the flow scanning cytometry and FITC-labeled antibodies to LBP, that there are at least 263 thousand LBP molecules in the Vero cells' surface. Blocking of the molecules by rabbit polyclonal antibodies to 43 kD of the recombinant LBP (rLBP) was shown to inhibit the VEE virus replication in Vero cells by more than 300,000 times, which made them virtually resistant to the possibility of VEE virus infection. This also confirmed that LBP is a target-molecule for VEE virus in Vero cells with the interplay between VEE virus and LBP in the cells' surface being the initial stage of virions' penetration into the cell and of their replication inside the cell.

[Comparative evaluation of the response of rat-mothers to the natural pain squeaks of a ratling and to a tape recording of it]. / Sravnitel'naia otsenka reaktsii krysy-materi na natural'nyi bolevoi pisk krysenka i ego magnitofonnuiu zapis'.

Two kinds of stimuli were presented to the mother rat at random: the natural pain acoustic signal of its infant in response to electrical pain stimulation and the tape recording of the signal performed within the sound frequency region (up to 20 kHz). The mother rat was placed in a special long cage with two parts of different size. Her reaction was ethologically estimated. The natural pain signal proved to be more effective than its magnetic tape recording. The role of the spectrum ultrasound part of the pain acoustic signal is discussed.

[A method of assessing rat preference for different acoustic signals when seeking out pups]. / K metodike otsenki predpochteniia krysoi razlichnykh zvukovykh stimulov pri poiske krysenka

A female albino rat was placed into an opened T-maze, and her maternal behaviour was stimulated by pups laid beneath her. Afterwards the pups were removed and impulses of tone (7 and 14 kHz) and tape recording of pup's nociceptive signal were simultaneously presented from different maze alleys. Maternal preference was checked by the predominant direction of seeking during random interchange of the sound sides. In 8 Wistar rats, preference for pup's nociceptive signal was observed.