[West Nile virus infection of agricultural animals in the Astrakhan region, as evidenced by the 2001-2004 serological surveys].

Sera sampled from 2,884 farming animals in the Astrakhan region in 2001 to 2004 were investigated by the hemagglutination inhibition test (HIT) in order to indicate specific antibodies to West Nile virus (WNV). HIT-positive samples were investigated by the neutralization test (NT). WNV antibodies were detected in all the examined species of animals: horses (the proportion of positive tests throughout the observation averaged 9.8%; the agreement with NT results was 94.1%), cattle (6,4 and 72.%), camels (5.2 and 41.7%), pigs (3.1 and 75%), and sheep (2.2 and 57.1). Relationships between the environmental features of WNV in different natural zones, the infection rate, and the conditions of keeping farming animals in the Astrakhan region are analyzed.

[Combined tumor chemotherapy/gene therapy based on the activation of antineoplastic agents by genetic constructions of cytochromes p450]. / Kombinirovannaia khimioterapiia/genoterapiia opukholei na osnove aktivatsii protivoopukholevykh preparatov geneticheskimi konstruktsiiami tsitokhromov semeistva p450.

This article generally reviews new original two-stage approach to an effective treatment of solid cancers by killing tumour cells by the activation of a prodrug after the gene encoding for an activating enzyme has been targeted to the malignant cell. The experimental data concerning gene therapy for malignant tumours by using oxazaphosphorines and cytochrome P450 in a novel combined chemotherapy/cancer gene therapy strategy discussed.

[Reaction of the sympathetic-adrenal medulla system in young rats of different age to subcutaneous administration of a cardiotoxic dose of noradrenaline]. / Reaktsiia simpato-adrenomedulliarnoi sistemy krysiat razlichnogo vozrasta na podkozhnoe vvedenie kardiotoksicheskoi dozy noradrenalina.

A quantitative histo-fluorescent investigation of the adrenal medulla and cardiac sympathetic nerves in young rats of various age has demonstrated a high degree in development of the adrenal medulla and a low density in arrangement of fluorescent nervous terminals in the ventricular myocardium in 3-week-old rats. During this period the animals show a low sensitivity to the catecholamine stress. At the age of 1.5 months the development of the sympatho-adrenomedullary system reaches the level specific for a mature animal; sensitivity to the norepinephrine stress increases noticeably, manifesting as a sharp activation of catecholamines secretion by the adrenal medulla and a high lethality.

[The reflection of the motivational status in the spectral characteristics of the species-specific acoustic signals of the domestic cat]. / Otrazhenie motivatsionnogo sostoianiia v spektral'nykh kharakteristikakh vidospetsificheskikh akusticheskikh signalov domashnei koshki.

Spectral characteristics of species-specific acoustic signals were analyzed in cats under various unfavourable conditions: hunger, isolation, pain stimulation, agony. The increase in the need to get rid of the discomfort accompanied by the development of emotional excitation was reflected in spectral characteristics of produced signals. The frequency and duration of signals increased, their spectrum widened accompanied by spectral maxima shifted towards the high-frequency area similar to the range of formant frequencies in the signals of newborn kittens. The similarity between spectral characteristics of the above signals in adult and newborn cats might indicate the appearance of infantile features in adult cats under conditions of a marked desire to change the existing situation. The fact that motivational state was reflected in spectral characteristics of acoustic signals along with stable responses to the signals, spoke in favour of a considerable contribution made by communication to the organization of intraspecific relations.

[A comparison of the efficacy of the passive hemagglutination reaction and the reverse passive hemagglutination reaction for detecting the rotavirus antigen in feces]. / Sravnenie éffektivnosti ispol'zovaniia reaktsii passiv gemaggliutinatsii i reaktsii obratnoi passivnoi gemaggliutinatsii dlia indikatsii rotavirusnogo antigena v fekaliiakh.

These two tests have been used for the detection of a rotaviral antigen in feces of patients suffering from gastrointestinal disorders. Antibody erythrocytic rotaviral diagnostic agent has been employed in both the tests. A comparative analysis has demonstrated the specificity of both the tests for the indication of a rotavirus and a higher sensitivity of passive hemagglutination.

[Role of non-coronarogenic injuries of the myocardium in sudden death at various stages of postnatal ontogenesis]. / Rol' nekoronarogennogo povrezhdeniia miokarda pri vnezapnoi serdechnoi smerti v razlichnye periody postnatalnogo ontogeneza.

The study was performed on white inbred young (1 and 3 weeks old), sexually immature (1.5 months old), sexually mature (6 months old) and old (over 24 months old) male rats, who were subcutaneously administered noradrenaline at a dose of 2 mg/kg body weight. The degree of myocardial injury was assessed on frontal histotopographic heart sections stained by the method of Leigh and Regaud, obtained from dead and killed rats 6 hours after noradrenaline injection. The reaction of the adrenal cortical substance was investigated, using quantitative histofluorescent method. It has been shown that young rats have low sensitivity to catecholamine stress, with the sensitivity increasing by the period of sexual maturation and again decreasing in old animals. The animals' death is associated with higher degree of myocardial injury that accompanies a drastic increase in catecholamine secretion by the adrenals.

[Comparative histofluorescent study of cardiac sympathetic nerves and adrenal catecholamines in rats under immobilization stress and administered a toxic dose of noradrenaline]. / Sravnitel'noe gistofliuorestsentnoe issledovanie simpaticheskikh nervov serdtsa i katekholaminov nadpochechnikov krys pri immobilizatsionnom stresse i vvedenii toksicheskoi dozy noradrenalina.

Changes in the adrenergic nerves of the rat heart and dynamics of adrenal catecholamines during immobilization stress and administration of a toxic dose of noradrenaline were found to be of the same type in general. They were manifested by a decrease of the number of fluorescent nerve terminals in the cardiac ventricles and an increase of catecholamine content in the adrenal glands 24 hours after the beginning of the experiment.

[The adrenal medulla and adrenergic innervation of the ventricles of the heart during the postnatal period of ontogenesis of the white rat (histofluorescent study)]. / Mozgovoe veshchestvo nadpochechnikov i adrenergicheskaia innervatsiia zheludochkov serdtsa v postnatal'nom periode ontogeneza beloi krysy (gistofliuorestsentnoe issledovanie).

The sympathetic innervation of the cardiac ventricles and dynamics of catecholamine contents in the adrenal medulla have been investigated in inbred white rats (1-3-week-old, immature, mature and old animals). During 1-3 weeks of age, development of adrenergic innervation of the heart is observed, in 1.5-month-old rats in approaches that in mature animals. In the old rats the arrangement density and fluorescent intensity of the adrenergic terminals of the cardiac ventricles in comparison to those in the mature animals decreases considerably. Catecholamine contents in the adrenal medulla in 3-week-old rats practically reaches those specific for mature animals. In the old animals the amount of catecholamines in the adrenal medulla decreases by 20%, comparing to those in the mature animals. Thus, maturation of the mediator link of the sympatho-adrenomedullary system is performed in it later than the hormonal one, while processes of old age involution are more intensive.

[Antigenic properties of variants of the influenza virus H7N7 and its recombinants]. / Antigennye svoistva variantov virusa grippa H7N7 i rekombinantov.

Passages of the A/seal/Massachusetts/1/80 strain in different biological systems (chick embryos, mice, chickens, organ cultures of human embryo trachea) yielded variants differing from the original virus both in their biological and antigenic properties. The M20 variant selected in passages of the seal virus in mouse lungs differed from the latter only in biological but not antigenic properties. The OC20 and C20 variants produced by passages of the seal virus in organ cultures and chicken lungs differed from the original virus only antigenically. The antigenic properties were examined by the HI test using monoclonal antibodies to the A/seal/Massachusetts/1/80 strain. In addition, the HI test with the selected variants and individual clones of the seal virus as well as recombinants produced with this virus revealed variability of the epitope of hemagglutinin reacting with monoclone 71/4. Because mice, chickens and chick embryos had no specific antibodies to the A/seal/Massachusetts/1/80 strain, a conclusion is drawn on the possibility of antigenic variability of influenza A virus in nonimmune hosts.

[Transient minor fractions of human serum albumin: physico-chemical properties]. / Tranzitornye minornye fraktsii syvorotochnogo al'bumina cheloveka: fiziko-khimicheskie svoistva.

From 7 to 8 minor fractions were isolated from normal and pathologically altered human blood serum albumin by means of isoelectric focusing in borate-polyol system. As distinct from the whole albumin molecule, these minor fractions contained 12-14% carbohydrates, I-1.2% of which were linked by covalent bonds while the rest of it were absorbed. The fractions included a number of amides, amount of which was gradually elevated with an increase in the isoelectric point. As shown by circular dichroism studies content of alpha-spirals decreased from 20% to 5% in the proteins, depending on the pI value. Spontaneous deamidation was noted during storage. Normally the content of these proteins constituted from 3% to 4%; in liver cirrhosis it might increase up to 50%.

Comparative studies on biological properties and genome composition of influenza virus recombinants.

Some biological properties and the genome composition of antigenic recombinants obtained by crossing of human and animal influenza viruses were studied. Analysis of the recombinants has shown that upon heating of virions in vitro thermostability of the haemagglutinin (HA) does not necessarily correlate with the properties of parent HA; apparently it depended not only on the properties of the HA itself, but also on the peculiarities of other virion proteins. All recombinants obtained by crossing of pathogenic and apathogenic for mice parents either had a reduced pathogenicity for mice or were apathogenic. In some instances, reduction or loss of pathogenicity was observed in recombinants which inherited only one gene from the apathogenic parent; however, the data obtained suggest that pathogenicity involves functions of a number of genes. Human and animal influenza virus strains under study proved to be capable of replication in human embryo tracheal and kidney organ cultures. The degree of reproduction of the recombinants was either lower or higher as compared to the parent strains.

[Use of organ cultures of animal trachea and lung for studying respiratory viruses]. / Primenenie organnykh kul'tur trakhei i legkogo zhivotnykh dlia izucheniia nekotroykh respiratornykh virusov

Organ cultures of the trachea and the lungs of newborn guinea pigs, rabbits, chickens, cow and pig embryos supported multiplication of influenza A2 and adenovirus type 3 viruses. Trachea organ cultures were shown to be more sensitive to the viruses under study. Organ cultures of the chicken trachea can be used for diagnosis of respitaroy virus infections.

Some observations on the circulation of influenzaviruses in domestic and wild birds.

Four viruses isolated from poultry in the USSR and Poland were identified as influenza A strains. One strain was closely related to fowl plague virus, the second showed an antigenic relationship to A/chicken/Scotland/59 (Hav5N1), and two others were antigenically related to A/duck/Ukraine/1/63 (Hav7Neq2) and A/duck/England/56 (Hav3Nav1). Antibodies to different strains of influenzavirus were detected in sera collected from poultry and from wild birds in the northern area of the USSR. More of the sera collected from migratory sea birds in the autumn gave HI reactions than did those collected in the spring. HI reactions were of higher titre when recent locally isolated viruses were used than with reference strains of influenzavirus. Sera collected in the autumn of 1969 from wild sea birds (mostly herring gulls, ducks, arctic loons, and long-tailed ducks) frequently showed HI activity not only with avian influenzavirus but also with A/equine/Miami/1/63 (Heq2 Neq2) and A/Hong Kong/1/68 (H3N2). The significance of these findings is discussed.