Co-Circulation of Coronaviruses among Rodents and Insectivores

Coronaviruses (family Coronaviridae, genera Alphacoronavirus and Betacoronavirus) are the causative agents of respiratory, intestinal and neurological diseases in humans and animals. Natural reservoirs of coronaviruses include bats, rodents and insectivores, however, the circulation of coronaviruses among rodents and insectivores in the Russian Federation has been unexplored. The aim of the study was to investigate the diversity of coronaviruses among rodents and insectivores co-inhabiting natural biotopes. Materials and methods. Rodents (68 specimens) and shrews of the genus Sorex (23 specimens) were caught in a limited forest area not exceeding 1.5 sq. km, in the vicinity of Novosibirsk. All samples were screened using reverse transcription polymerase chain reaction followed by sequencing. Results and discussion. Four distinct coronaviruses have been detected in four species of small mammals. Rodent-borne coronaviruses were classed within subgenera Embecovirus, genus Betacoronavirus, and demonstrated host-associated phylogenetic clustering. The level of homology between the new RNA isolates from red-backed vole (Myodes rutilus), root vole (Microtus oeconomus) and field mouse (Apodemus agrarius) is 85.5–87.7 %. The nucleotide sequences of Siberian coronavirus isolates are closely related (>93 % homology) to previously published sequences in each of the carrier groups found in Europe and China, which suggests their common evolutionary origin. The coronavirus identified in the common shrew (Sorex araneus) belongs to the genus Alphacoronavirus, but is significantly different (>36 % difference) from earlier identified strains included in the genus. It has been shown that different coronaviruses co-circulate in a limited area among rodents and insectivores

Molecular Epidemiology of Pathogenic Hantaviruses in the Far East of Russia, 2015-2018

Human pathogenic hantaviruses, belonging to the family Hantaviridae, genus Orthohantavirus, are disseminated worldwide and cause hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia. In the Far East of Russia Hantaan (HTNV), Amur (AMRV) and Seoul (SEOV) viruses are etiologic agent of HFRS, while the human pathogenic potential of other seven hantaviruses, circulating in this region, has not been researched adequately yet. Objective of the study was genetic identification of hantaviruses, associated with HFRS in the Far East of Russia during 2015-2018. Materials and methods. Blood samples of 64 HFRS patients from Jewish Autonomous Region, Khabarovsk and Primorsky Territories were analyzed for hantavirus RNA using reverse transcription polymerase chain reaction. Results and discussion. A total of 19 viral RNA isolates from HFRS patients were genetically typed. Etiologic agents of HFRS were three pathogenic hantaviruses: HTNV (13 isolates), AMRV (3 isolates), SEOV (3 isolates). Three genetic lineages were identified among HTNV, two lineages among AMRV One genetic variant of SEOV virus was identified among HFRS patients, which was more close to the strains from South-Eastern Asia than to those from the neighboring countries

Photoemission of Bi2_2Se3_3 with Circularly Polarized Light: Probe of Spin Polarization or Means for Spin Manipulation?

Topological insulators are characterized by Dirac cone surface states with electron spins aligned in the surface plane and perpendicular to their momenta. Recent theoretical and experimental work implied that this specific spin texture should enable control of photoelectron spins by circularly polarized light. However, these reports questioned the so far accepted interpretation of spin-resolved photoelectron spectroscopy. We solve this puzzle and show that vacuum ultraviolet photons (50-70 eV) with linear or circular polarization probe indeed the initial state spin texture of Bi$_2$Se$_3$ while circularly polarized 6 eV low energy photons flip the electron spins out of plane and reverse their spin polarization. Our photoemission calculations, considering the interplay between the varying probing depth, dipole selection rules and spin-dependent scattering effects involving initial and final states explain these findings, and reveal proper conditions for light-induced spin manipulation. This paves the way for future applications of topological insulators in opto-spintronic devices.Comment: Submitted for publication (2013

HANTAVIRUS SEEWIS AND RESERVOIR SPECIES IN SIBERIA

Genetic evidence of shrew-borne hantavirus in Russia is presented here. Impressive distribution of a hantavirus Seewis (SWSV), previously discovered in the Eurasian common shrew from Switzerland, was demonstrated in Siberia among closely related shrew species: Sorex araneus, S. tundrensis and. S. daphaenodon. SWSV circulation was shown in Altai Republic, Krasnoyarsk Krai, Kemerovo and. Novosibirsk regions, surburbs of Novosibirsk and Irkutsk Cities

Eye Hydrodynamics after Combined Treatment of Primary Open-Angle Glaucoma and Complicated Cataract

Aim: To study hydrodynamics of the eye after combined treatment – a combination of laser activation of trabecula and cataract phacoemulsification – in a comparative aspect.Material and methods. The study included 65 patients (65 eyes) with initial and advanced stages (I–II stages) of primary open-angle glaucoma (POAG) and complicated cataract. Among the patients there were 38 women (58.5 %) and 27 men (41.5 %), the average age was 68.8 ± 8.2 years. The follow-up period is 12 months after the treatment. The patients were divided into two groups: the main one – 33 patients (33 eyes) who underwent combined treatment – YAG-laser activation of trabecula (YAG-LAT) and phacoemulsification of cataract with intraocular lens (IOL) implantation, the control group – 32 patients (32 eyes) who underwent only phacoemulsification.Initially, the average intraocular pressure (IOP) (P0) in the main and control groups was 20.72 ± 3.39 mm Hg and 21.02 ± 3.55 mm Hg respectively. The average number of antihypertensive drugs used in the study group was 1.53 ± 0.64, in the control group – 1.34 ± 0.55.Results. There were no intraand postoperative complications. By the end of the follow-up period, a significant decrease in the average IOP level compared to its preoperative value by 29.2 % was determined in the main group, and 9.8 % in the control. The average number of antihypertensive drugs used in the study group decreased from 1.53 ± 0.64 to 0.67 ± 0.59 (p < 0.05), in the control group of patients, on the contrary, the average number of antihypertensive agents increased from 1.34 ± 0.55 to 1.91 ± 0.70 (p < 0.05).Conclusion. In the long-term postoperative period after combined treatment (YAG-LAT + phaco), IOP normalization was achieved in 96.9 % of cases, as well as a significant increase in visual acuity of patients. The developed method of treatment is safe, has a minimal risk of complications and can be used for the treatment of patients with initial stages of POAG in combination with complicated cataracts with increased IOP level, inefficiency of antihypertensive therapy

GENETIC ANALYSIS OF HOKKAIDO HANTAVIRUS AMONG MYODES RUFOCANUS IN THE BAIKAL LAKE AREA

Hokkaido hantavirus (HOKV) identified originally in the grey red-backed vole (Myodes rufocanus) in Hokkaido, Japan. Subsequent studies showed different genetic lineages of HOKV in Sakhalin, Buryatia and Far Eastern regions of Russia and in China. Tissuesfrom 68 arvicolid rodents, captured in regions south and west of Baikal Lake, were initially tested for hantaviral antigen by ELISA, and tissues from antigen-positive rodents were analyzed for hantavirus RNA by RT-PCr. Taxonomic identification of host species was based on phylogenetic analysis of partial cytochrome b gene sequences. Hantavirus Land S-segment sequences were detected in two antigen-positive M. rufocanus, from the Tunka region of Buryatia Republic (south side) and the Olhon region of Irkutsk Oblast (west side). Sequence analysis showed that the newfound hantavirus strains, designated Baikal and Siberia, represented genetic variants of HOKV Previously unknown genetic variant designated Siberia was identified in M. rufocanus captured in Olhon region. Second genetic variant from Tunka region, designated Baikal, was closely related to previously described hantavirus strain from the same region. Alignment and comparison of the nucleotide and amino acid sequences showed intra-strain differences of 18,4 % and 5,3 % for the L segment and 17,4 % and 3,5 % for the S segment, respectively. Sequence divergence from geographically distant HOKV strains were 17,4-21,5 % and 3,9-6,8 % for the L segment and 15,2-17,0 % and 3,3-4,0 % for the S segment, respectively. Phylogenetic analysis, based on a 346-nucleotide region of the L segment, revealed four lineages represented by previously reported variants from Japan and Sakhalin (strains Kitahiyama128L/2008, Tobetsu35L/2010 and Sakhalin99L/1998), Shkotovo in Far-Eastern Russia (strain Khekhtsir37L/2002) and the new variants from Baikal Lake. Analysis of the N protein, coding by the S segment, identified specific amino acid signatures for YJRV of Lys5, Arg26, Val/Ile68, Val/Ala9 He262, Pro283. Conclusions: HOKV is widespread across the geographic range of its arvicolid rodent reservoir host

Coronaviruses in rodents and insectivores in Altai Republic

Coronaviruses (family Coronaviridae, genera Alphacoronavirus, Betacoronavirus) are dangerous viral pathogens that have caused three outbreaks of severe respiratory diseases, SARS, MERS, COVID-19. In Russia, data on coronaviruses in natural reservoirs are limited, as investigations began only during the COVID-19 pandemic.The aim. To study the diversity of coronaviruses among rodents and insectivores in the Republic of Altai.Materials and methods. Rodents (n  =  67) and shrews (n  =  52) were captured in 2022. Samples were analyzed by reverse transcription-polymerase chain reaction followed by sequencing.Results and conclusions. Four samples from rodents (Myodes rutilus, M. glareolus, Apodemus peninsulae, A. agrarius) and two samples from an insectivore (Crocidura sibirica) were positive for coronaviruses, among which three different coronaviruses were detected. Rodent-borne coronaviruses are classified in the genus Betacoronavirus, subgenera Embecovirus, and have shown host associated clustering. The nucleotide sequences of Siberian coronaviruses from rodents were identical for closely related species (M. rutilus and M. glareolus, A. agrarius and A. peninsulae) and close (> 94 % homology) to previously published sequences in each of the groups of carriers found in the territory Novosibirsk region, Europe and China. The coronavirus identified from the insectivore, possibly belonging to a new subgenera of the family Coronaviridae, has also been assigned to the genus Betacoronavirus.Conclusion. Five species of natural carriers of three different coronaviruses were detected in the Altai Republic. A high level of identity of coronaviruses genomes from rodents has been revealed, indicating a relatively low rate of their evolution

Hantavirus infection in patients with fever of unknown origin and in small mammals in the Baikal region

Background. Hantavirus infections are one of the most important zoonotic diseases in the Russian Federation. However, the pathogenicity of Hantaviruses circulating in Siberia is still unknown. The aim of the study was to assess the incidence of Hantavirus infection in patients with fever of unknown origin from Irkutsk region and adjacent territories. Materials and methods. Serum samples collected in 2016 from individuals with symptoms of health deterioration were screened by ELISA to investigate possible Hantavirus infection, in addition to tick-borne infections. Depending on date of tick bite specific immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies to tick-borne encephalitis, borreliosis and Hantavirus were tested by ELISA or screened by PCR for tick-borne encephalitis, borreliosis, human granulocytic anaplasmosis and monocytic erlychiosis RNA/DNA. Results. Out of 92 serum samples, 6.5 % were positive for hantavirus-specific antibodies, which is at least twice higher than the seroprevalence among healthy people in the Irkutsk region. IgM and IgM+IgG antibodies were found in 5.4 % of cases, while IgG antibodies - in 1.1 % of cases. The clinical symptoms among sero-positive patients were fever, skin lesion, fatigue syndrome, headache and lymphadenitis. IgM antibodies to borreliosis were found in two hantavirus sero-positive cases. Lung tissues from small mammals captured in 2016 were screened by ELISA for the presence of Hantavirus antigen. Hantaviral antigen was detected in 6.3 % of 48 samples. Conclusions. Thus, present and previous studies demonstrate existence of natural foci of Hantavirus infections in addition to tick-born infections in the territory of the Irkutsk region