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A N Lukashev

Publications and source records attributed to A N Lukashev.

9 recordsLinked to original sources
PubMed2004

Recombination in uveitis-causing enterovirus strains.

The complete nucleotide sequences of three human echovirus (EV) 11 strains and one EV19 strain, all of which caused outbreaks of enterovirus uveitis (EU), a new infant disease first identified in 1980 in Siberia, were determined. One EV11 strain which caused an outbreak of sepsis-like disease in Hungary was also sequenced. All four EV11 strains were mosaic recombinants of the prototype EV11 strain Gregory, with their non-structural coding regions and 5' NTRs being more similar to other prototype enteroviruses (EV1, EV9). However, this finding is probably a feature of all circulating enterovirus strains and may not be related to their altered virulence. A full genome sequence comparison of the three subtypes of EU-causing strains excludes the role of recent recombination in their emergence, and points to their independent emergence.

5' Untranslated Regions↗
PubMed2003

Molecular epidemiology of enteroviruses causing uveitis and multisystem hemorrhagic disease of infants.

We studied molecular epidemiology of highly virulent echovirus 11 and 19 strains that were isolated during five outbreaks of enterovirus uveitis (EU) in Siberia in 1980-1989, and three outbreaks of multisystem hemorrhagic disease of infants (MHD) in 1988-1991. Three genome regions, 5'NTR, VP1-2A junction, and a fragment of 3D polymerase, were analyzed. Phylogenetic grouping in the VP1-2A region correlated with serotyping results. All studied EV11 and EV19 strains, including the prototype EV11 and EV19, formed a major phylogenetic group in VP1-2A region. Within that group, several EV11 isolates from EU and MHD outbreaks formed a distinct cluster in VP1-2A and 5' NTR genome regions, designated EV11/B. All strains of this cluster possessed high virulence for monkeys compared with the prototype echoviruses. Subgrouping within this cluster correlated with year of virus isolation, not with the disease the viruses caused in infants (EU or MHD).

Base Sequence↗
PubMed2002

Phylogenetic and serological characterization of echovirus 11 and echovirus 19 strains causing uveitis.

The strains of echovirus 19 (EV 19) and echovirus 11 (EV11), isolated from infants with similar clinical symptoms of acute enterovirus uveitis (EU) in Russia (Siberia) in 1980-1989, were investigated phylogenetically (nucleotide sequence of a 300 nt fragment in 5' NTR and VP4 junction) and serologically. The result confirmed that viruses belong to the Enterovirus genus, with 58-80% nt sequence homology with previously sequenced enteroviruses, and showed the genetical identity between the strains isolated during each of five outbreaks of the EU. The results also demonstrated that isolates from the last three outbreaks of EU belong to the same phylogenetic group despite the remarkable spatial and temporal distance between the outbreaks. The results confirm the role of these echoviruses in the etiology of the EU. Based on phylogenetic and serological comparisons the studied strains were divided into three distinct groups: group I, EV19/K (Krasnoyarsk, 1980-1981), group II, EV11/A (Krasnoyarsk, 1982), group III, EV11/B (Krasnoyarsk, 1986; Omsk, 1987-1988; Irkutsk, 1989). Minor details of the epidemiology of the outbreaks were also revealed.

5' Untranslated Regions↗
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[Molecular epidemiology of the ECHO 30 virus in Russia and CIS countries].

Nucleotide sequences of the VP1 genome of 28 ECHO 30 strains isolated in 1998-2002 in Russia and several CIS countries were determined. The EV30 studies strain were divided into 4 groups according to isolation place and time. Group 1 is presented by 2 strains isolated in 1998 in Russia and Byelorussia. Group 2 comprises 17 strains isolated in 1999-2000 in Russia (its southern regions and Stavropol Territory), Ukraine, Georgia, and Azerbaijan. Five strains isolated in 2002 in Russia (Kalmykia) belong to Group 3; and Group 4 has 4 strains isolated in 2002 in Moldova and Russia (Magadan). A frequently changing EV30 subtype was simultaneously detected in extensive territories.

Capsid Proteins↗
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[Acute enterovirus uveitis in infants].

Enterovirus uveitis (EU) is a new infant eye disease that was first detected and identified in Russia in 1980-1981. Three subtypes of human echoviruses (EV19K, EV11A, and EV11/B) caused 5 nosocomial outbreaks of EU in different Siberian cities and towns in 1980-1989, by affecting more than 750 children mainly below one year of age. Sporadic and focal EU cases (more than 200) were also retrospectively diagnosed in other regions of Russia and in different countries of the former Soviet Union. There were following clinical manifestations: common symptoms of the infection; acute uveitis (rapid focal iridic destruction, pupillary deformities, formation of membranes in the anterior chamber of the eye); and in 15-30% of cases severe complications, cataract, glaucoma, vision impairments. Uveitis strains EV19 and EV11 caused significant uveitis in primates after inoculation into the anterior chamber of the eye, as well as sepsis-like fatal disease with liver necrosis after venous infection. The uveitis strains are phylogenetically and pathogenetically close for primates to strains EV19 and EV11 isolated from young children with sepsis-like disease. The contents of this review have been published in the Reviews in Medical Virology, 2004, vol. 14, p. 241-254.

Animals↗
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[A role of recombination in the evolution of enteroviruses].

Enteroviruses, members of the family Picornaviridae (more than 70 serotypes), are distributed throughout the world and cause a broad spectrum of clinical manifestations in man and animals. Human enteroviruses are classified into 5 species: human enteroviruses A to D, and Poliovirus. Recombination has long been known to be an important property of poliovirus genetics; however, recombination has been recently shown to be also ubiquitous in non-polio enteroviruses. Prototype enterovirus strains have complex phylogenetic relations and all currently available enterovirus strains are recombinant to prototype strains. The extremely high rate of recombination allows the fragments of the enterovirus genome to evolve independently at a microevolutionary scale. Recombination strictly takes place between the members of the same species, usually outside the capsid-encoding genome region. Therefore, it can be concluded that the species enterovirus exists as a worldwide reservoir of the genetic information that shuffles frequently to produce new virus variants. This new model of the genetics of enterovirus accounts for failures to associate the serotype of enteroviruses and the form of the disease caused. The contents of this review have been published in the Reviews in Medical Virology, 2005.

Biological Evolution↗
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[Superacute lethal liver necrosis in monkeys infected with highly pathogenic variants of enteroviruses (ECHO 11 and ECHO 19 viruses)].

The authors studied the phenomenon of superhigh virulence for monkeys of viruses ECHO 11 (E11) and ECHO 19 (E19) isolated in 1981-1991 in Russia and Tadzhikistan from children with acute enterovirus uveitis or severe enterovirus infection. In 21 morphologically examined animals after coma, macrofocal or total necrosis of hepatocytes in weak inflammation was seen as early as experiment day 1-6. Hepatic lesion interpreted as hepatosis underlies acute hepatic failure with lethal outcome. The most intensive reproduction of viruses E11 and E19 occurred in the liver. Changes in the kidneys, lungs, spleen, adrenals, CNS detected in many animals aggravated the disease, but were not the primary cause of death. The disease in monkey was similar by the main criteria to superacute lethal diseases (acute hepatic failure against massive hepatic necrosis, hemorrhagic syndrome) registered in outbreaks of E11 and E19-virus infection in children in the USA, Great Britain, Israel, Russia and Ukraine. Monkeys can be used as man-adequate model for study of enterovirus superacute lethal necrosis of the liver.

Animals↗
PubMedDate not supplied

[Enteroviral persistence in eye infections in monkeys (postuveitis syndrome)].

Follow-up (5.5 years) of monkeys with a history of acute enterovirus uveitis (AEU) after intraocular infection with ophthalmotropic ECHO 11 and ECHO 19 strains showed progressive changes in the infected eye; destruction of the iris, formation of films in the anterior chamber of the eye, deformation of the pupil, and signs of cataract and glaucoma. A short (1-30 days) stage of active reproduction of infective virus (up to 10(10) TCD50/g tissue in the first days postinfection) was followed by the second very long stage of limited specific multiplication of virus in ocular tissues. The virus was not detected during the second stage, but its components (virusspecific antigen and crystalloid accumulations of virions) were found in ophthalmic and conjunctival tissues; moreover, high levels of neutralizing antibodies were detected in the blood. The results indicate AEU transformed into a stubborn persistent infection of the eye in monkeys. The findings of this follow-up and published reports about many-year follow-up of children with AEU permit us to classify a post-uveitis disease as a special nosological form of a persistent enterovirus infection and denote it as enterovirus post-uveitis syndrome. The main signs of this syndrome are a history of AEU, progressive destructive changes in the anterior segment of the eye, presence of virus components in ocular tissues in remote periods after infection, and high antibody level in the blood.

Animals↗