Biocompatibility and Bioresorption of 3D-Printed Polylactide and Polyglycolide Tissue Membranes.

We studied biocompatibility and bioresorption of 3D-printed polylactide and polyglycolide tissue membranes. Ultrasound microscopy and histological examination showed that membranes fabricated of a copolymer of lactic and glycolic acids in a mass ratio of 1:9 are bioresorbed and have good biocompatibility with soft tissues (connective tissue, adipose tissue, and epithelium). An important feature of the copolymer membranes, which differs them from pure polylactide membranes, is the formation of a thin fibrous capsule that did not interfere its destruction by the mechanism of hydrolytic resorption.

[Characteristics of EEG-based biofeedback treatment procedures in normal and complicated pregnancy].

Electroencephalographic characteristics during the application of EEG-based biofeedback treatment procedures for non-drug correction of functional disturbances were compared in pregnant women with normal and complicated pregnancy. As compared to normal-pregnancy group, in the abortion-threat group, the initial EEG data were characterized by a significant reduction of alpha-rhythm at the expense of theta and beta enhancement. Average number of successful attempts to voluntary regulate the EEG rhythms was significantly reduced in the abortion threat group (55.4 +/- 4.7%) as compared to the normal group (70.2 +/- 5.0%). The least efficiency was observed for EEG beta-reduction procedures. All patients demonstrated significant positive changes in self-estimated values of health and mood. However, though the anxiety level significantly decreased in the group with normal pregnancy, it increased in the abortion-threat group. Thus, the EEG-based biofeedback procedures were shown to be an effective supplement to conventional methods of complex therapy of pregnancy complications, but they required taking into consideration the EEG and subjective features of the patients in case of complicated pregnancy.

[Biofeedback training and human functional state control]. / Adaptivnoe bioupravlenie s obratnoi sviaz'iu i kontrol' funktsional'nogo sostoianiia cheloveka.

Biofeedback (BFB) training paradigm has outstanding place among various approaches to non-phrarmacological human functional state correction. Being an universal way for voluntary self-regulation of physiological functions, it is characterized by efficacy, accessibility and absence of side effects. However, the lack of fundamental knowledge about the BFB mechanisms leads to existence of numerous difficulties and problems that seriously limit the BFB possibilities. Most difficulties seem to concern the problem of adequate choice of BFB type or parameter being voluntary controlled via feedback signals. Some ways to solve this problem are drown on the base of general systems theory. It is shown that BFB procedures could be especially effective in conditions of close interaction between the BFB mechanisms and the central regulatory mechanisms. Such interaction could be reacheb by utilization of certain characteristics of brain electrical activity reflected in the electroencephalogram (EEG). The most perspective seems to be the utilization of discrete narrow band EEG spectral components, individual resonance EEG oscillators or some correlates of human EEG amplitude modulation processes.

[An analysis of the amino acid sequence of the heavy subunit of the hemagglutinin in influenza virus A/Alma-Ata/1417/84]. / Analiz aminokislotnoi posledovatel'nosti tiazheloi sub''edinitsy gemaggliutinina virusa grippa A/Ama-Ata/1417/84.

An analysis of the amino acid sequence of influenza A/Alma-Ata/1417/84 (H1N1-Hsw1N1 serovariant) virus hemagglutinin heavy chain deduced from the nucleotide sequence of cloned full-size DNA complementary to the 4th segment of genome RNA was carried out. Unlike A/New Jersey/8/76 virus, the hemagglutinin of the virus under study was found to be more similar in the rate of HA1 homology, amino acid sequence of the signal peptide, antigenic sites Sa, Ca, and the receptor-binding site to human influenza viruses isolated in the 1930-1980-ies, in particular to influenza A/Taiwan/1/86 virus. It is assumed that an influenza virus more adapted to the human population like the strain A/Alma-Ata/1417/84 may be an etiological factor of a new influenza pandemic.

[Synthesis, cloning, and determination of the primary structure of a full-length DNA copy of the gene for influenza A/Alma-Ata/1417/84 virus (H1N1-serovariant HSW1N1) hemagglutinin]. / Sintez, klonirovanie i opredelenie pervichnoi struktury polnorazmernoi DNK-kopii gena gemaggliutinina virusa grippa A/Alma-Ata/1417/84 (N1N1-serovariant HSW1N1).

The full-length copy of the hemagglutinin gene RNA of the influenza virus A/Alma Ata/1417/84 (Hsw1 N1-serovariant) has been synthesized and cloned on Escherichia coli plasmid pBR327. The complete nucleotide sequence of the cloned DNA copy was determined by the Maxam-Gilbert procedure. The predicted amino acid, sequence of HA1 hemagglutinin subunit was compared with the sequences of HA1 subunits from other H1N1-subtype influenza virus strains. It has been found that the structure of the HA1-subunit of the studied strain is most similar to the structure of the identical region of the A/New Jersey/18/76 hemagglutinin.

[The induction by the influenza virus A/H1N1 (serovariant Hsw1N1) and its glycoproteins of congenital pathology in mice]. / Induktsiia virusom grippa A/H1N1 *serovariant Hsw1N1) i ego glikoproteidami vrozhdennoi patologii u myshei.

Influenza A/H1N1 (serovariant Hsw1N1) virus, a sum of isolated glycoproteins, separately neuraminidase "heads", inoculated into white random-bred female mice, induced in some of the offsprings the pathology clinically and pathomorphologically similar to previously described slow virus infection. At the same time, the pathology in the offsprings caused by the antigenic virus variant under study was characterized by complete absence of fur and more dynamic progress of the disease. It is quite obvious that glycoproteins, particularly neuraminidase, are the molecular biological basis of dystrophic and degenerative changes in the organs of baby mice due to desialization and increased fluidity of capillary endothelium membranes and, possibly, CNS and other organ cells.

[High-frequency jet ventilation of the lungs]. / Struiinaia moduliruiushchaia vysokochastotnaia iskusstvennaia ventiliatsiia legkikh.

A study of high-frequency jet ventilation (HFJV) has been conducted on the lung model IS-800. Considerable changes in the tidal volume (TV) have been observed during HFJV with frequency of respiration (f) 60 and 100 min-1, which ensures non-monotonous respiration. Constant fluctuations of positive end-expiratory pressure (PEEP), maximum tracheal inspiratory pressure (Pmax.tr.) and amplitude respiration (Amp. R) were in the linear dependence on TV changes. f increase led to a considerable decrease in TV fluctuations and AMP.R values due to PEEP increase and Pmax.tr. reduction.

[The use of microcomputers for calculating the indices of the hemodynamics, pump and contractile function of the left heart]. / Primenenie mikrokal'kuliatorov dlia rascheta pokazatelei gemodinamiki, nasosnoi i sokratitel'noi funktsii levogo serdtsa.

A programme is presented for the calculation of parameters reflecting pump and contractile functions of the left ventricular myocardium on Soviet-made microcomputer B3-34. The programme makes it possible to intensify studies 2.5-3-fold, assess hemodynamics many times at different stages of the investigation, obtain results and promptly give practical recommendations, which is of utmost importance in intensive care and resuscitation.

[Functional activity of glycoproteins from interepidemic isolates of the influenza virus]. / Izuchenie funktsional'noi aktivnosti glikoproteidov mezhépidemicheskikh izoliatov virusa grippa.

The results of the study into the function of glycoproteins of influenza viruses isolated in the 1987 interepidemic period. Natural isolates were found to have virus particles with deficient neuraminidase activity but retained hemolytic and infectious activity. Biological sequences of the lack of neuraminidase activity in the isolates consisted in disorders of sialic acid metabolism in the infected cells, blocking of the receptor site of hemagglutinin and increased sensitivity to inhibitors. It is assumed that the interepidemic virus isolates represent a biologically heterogeneous population in which particles with deficient neuraminidase activity are prevalent.

[Antigenic specificity of neuraminidase and structure of neuraminidase gene of influenza A(H1N1) serotype Hsw1N1 viruses isolated from man and animals]. / Antigennaia spetsifichnost' neiraminidazy i struktura genov neiraminidazy virusov grippa A(H1N1)-serovariant Hsw1N1, vydelennykh ot cheloveka i zhivotnykh.

The enzyme immunoassay and neuraminidase activity inhibition test using polyclonal and monospecific antineuraminidase sera were employed to establish the similarities and differences in the antigenic structure of neuraminidase of influenza A viruses (H1N1), serovariant Hsw1N1, isolated from man in Alma-Ata (USSR), 1984, New Jersey (USA), 1976, and Pazardjik (BPR), 1982, as well as from swine and birds. Oligonucleotide mapping revealed significant structural differences in the genes coding for neuraminidase of Hsw1N1 viruses. The experimental results indicate a high degree of the enzyme variability in this group of viruses.

[3 cases of isolating the influenza A virus with human hemagglutinin Hsw1 in 1983 in Alma-Ata]. / Tri sluchaia izoliatsii virusa grippa A s gemaggliutininom Hswl ot liudei v 1985 g. v Alma-Ate.

In the interepidemic period of late 1983 in Alma-Ata, influenza viruses with hemagglutinin of the swine subtype and neuraminidases N1 and N2 were isolated from humans. One of the strains, A/Alma-Ata/1044/83 (Hsw1N1), was isolated from the lungs of a man of 65 with the diagnosis of influenza and disseminated intravascular syndrome who had had communal and occupational contacts with swine. In paired sera of a sick child, and in seroepidemiological screening for influenza antibodies to swine influenza virus in low titres were detected in 34% of cases in subjects under 40. Radioimmunoassay of blood clots from subjects of the same focus revealed in one specimen the presence of swine influenza antigen.

[Antigenic and biochemical analysis of the proteins of influenza virus A/USSR/Alma-Ata/13/81 with hemagglutinin H1]. / Antigennyi i biokhimicheskii analiz belkov virusa grippa A/USSR/Alma-Ata/13/81 s gemaggliutininom H1.

An influenza A virus whose hemagglutinin belongs to subtype H1 (serovariant WS/33) and neuraminidase to subtypes N1 (serovariant A/PR8/34) N3 was isolated by a method of aborted infection in chick embryos in virological examinations of the lungs and trachea of a 3-month-old infant who died of acute respiratory virus disease during a seasonal rise of ARD incidence in Alma-Ata, the Kazakh SSR, in 1981. The oligopeptide composition of nucleoprotein protein and glycoproteins of the isolate differed from that of the corresponding proteins of the reference serovariants. The electrophoretic analysis of the isolate polypeptides revealed neuraminidase with molecular weight about 70 kD which is unlike the findings with previously known strains. The original structure of the influenza A/USSR, Alma-Ata/13/81 virus proteins rules out the likelihood of laboratory contamination.

[Effective method of isolating influenza virus on chick embryos]. / Effektivnyi metod vydeleniia virusa grippa na kurinykh émbrionakh

An effective method for isolation of influenza virus from the nasopharyngeal specimens of patients is described consisting of interruption of the virus reproduction cycle in chorioallantoic membranes of chick embryos (CECAM) at early stages of development of the infection followed by inoculation of infected CECAM homogenate into a fresh homologous medium. The new method of virus isolation is superior to the conventional one by a higher isolation rate, economy of material and time saving which is important for identification of influenza outbreaks.