Identification of the etiological agent of equine piroplasmosis in Western and Eastern Siberia

Equine piroplasmosis is a natural tick-borne infection caused by hemoprotozoan parasites of the order Piroplasmida, Babesia caballi and Theileria equi. Animals that recover from piroplasmosis remain persistently infected carriers and can transmit pathogens to vector ticks. Cases of equine piroplasmosis are periodically observed in Siberia, however, no agent of equine piroplasmosis has yet been genetically characterized in Russia. The aim of this work was studying the prevalence of the infectious agents of piroplasmosis in horses from Siberia and genotyping the detected agents. Blood samples from 155 horses were examined for the presence of Babesia and Theileria DNA by nested PCR with the subsequent sequencing of positive samples. DNA of T. equi was found in blood samples from 57.9 %, 38.5 % and 65.0 % of horses from Novosibirsk province, Irkutsk province, and the Republic of Altai, respectively. T. equi DNA was found in the samples from almost all sampling sites included in this study, indicating that most of the studied sites are endemic for equine theileriosis. Surprisingly, DNA of B. caballi was not found in any of the samples examined, even though this agent had previously been detected in many regions in Russia, including Altai. The analysis of the determined 18S rRNA gene sequences demonstrated that T. equi samples belonged to two genetic groups, which differed significantly by the sequences of the variable (V4) region of the gene. All T. equi sequences from group B were identical and corresponded to T. equi sequences found in the blood of horses from China and Korea, while T. equi sequences from group A differed by 1–5 nucleotide substitutions and were identical to the sequences from the blood of horses from India and Brazil or differed from them by single mismatches. Notably, in this study the presence of etiological agent of piroplasmosis in blood samples from horses in Russia was genetically confirmed for the first time

Detection of Babesia and Anaplasmataceae bacteria in small mammals from Irkutsk and Novosibirsk regions

Tissue samples from 228 small mammals captured from 2013 to 2015 in four districts of Irkutsk region and in one district of Novosibirsk region were examined for the presence of Anaplasmataceae bacteria and Babesia parasites by nested PCR method with subsequent sequencing of positive samples. In Ekhirit-Bulagatskiy District of Irkutsk region, Babesia microti DNA was found in 10.9 % of small mammals, Anaplasma phagocytophilum DNA - in 7.3 %, and Ehrlichia muris DNA - in 1.8 %. Infected mammals were not found in the other three examined districts of Irkutsk region. In Novosibirsk region, B. microti DNA was found in 8.9 % of small rodents, A. phagocytophilum DNA - in 8.9 % of small mammals, and Candidatus Neoehrlichia mikurensis DNA - in 8.9 % of small mammals. The identified infection agents corresponded to microorganism species and genetic variants previously found in Ixodes persulcatus ticks but not in ticks of other species

Anthropourgic Foci of Plague in Vietnam: Past and Present

The review contains the results of ecological-epizootiological and epidemiological investigations of plague in the territory of the Socialist Republic of Vietnam in 1989-2012. Studied has been the structure of epizootic triad - carrier-vector-pathogen. There is a low probability of plague foci occurrence in zones of tropical forests and savanna under the conditions of humid subequatorial climate. Main plague agent carrier on the Thai Nguyen Plateau is the synanthropic little rat, Rattus exulans . Specialized fleas species are absent on wild-living rats Rattus genus, as well as mice, and bandicoots, and the abundance of other species is small. It has been demonstrated that all the elements of the parasitic plague system are classified as introduced species. Thereupon it is inferred that plague foci in Vietnam are anthropourgic and are of anthropogenic origin solely. Plague cases in humans across the territory of the country were registered between 1898 and 2002. The most persistent ones functioned on the Thai Nguyen Plateau. Although epizootic activity of the foci in territory of the former endemic provinces has decreased, it is necessary to continue epizootiological monitoring further on in the modern period

MOLECULAR GENETIC ANALYSIS OF INFECTION AGENTS OF FARM ANIMALS ANAPLASMOSIS ON THE TERRITORY OF WESTERN AND EASTERN SIBERIA

A total of 452 blood samples of cattle, sheep and goat collected in different regions of Altai Republic, Altai region, Novosibirsk and Irkutsk regions were examined on the presence of Anaplasma DNA using nested PCR with subsequent sequencing of PCR fragments. Anaplasma DNA was found in all examined blood samples of goat, 75.2 % samples of sheep, and 49.3 % samples of cattle. A molecular genetic analysis has demonstrated that intraerythrocytic Anaplasma ovis circulates in goat and sheep blood, while an intraerythrocytic Anaplasma sp. Omsk and a new intraerythrocytic Anaplasma sp. Sibl22, which cannot be attributed to any known species, circulate in cattle blood. In addition to intraerythrocytic Anaplasma, DNA of monocytic Anaplasma bovis was found in one blood sample of cattle

BRIEF CHARACTERISTIC OF EUROPEAN GENOTYPE TICK-BORNE ENCEPHALITIS VIRUS STRAINS IDENTIFIED IN SIBERIAN REGION

The molecular-genetic analysis of 13 strains of Western genotype TBEV isolated in Western and Eastern Siberia demonstrated two groups of strains differed geneticallyfrom each other and had a high level of E gene sequences homology within each group. Nevertheless, the heterogeneity of biological propertiesfor some strains within a group was observed

SPECIES AND GENETIC VARIETY OF TICK INFECTIONS PATHOGENS ON THE TERRITORY OF THE EASTERN SIBERIA

The article sums up long-term, researches of studying of species and genetic variety of tick infections pathogens in combined, natural focuses of the Eastern Siberia. The results of the research testify to the high genetic variety of regional population, of tick-borne encephalitis virus that is represented, by the strains of Far-Eastern, West, Ural-Siberian genotypes, the strains of the group 886 and. 178-79. Infection of Ixodidae by the next pathogens: B. garinii, B. afzelii, R. sibirica, R. raoultii (генотипы. R. sp. DnS14, R. sp. DnS28), E. muris, A. phagocytophilum и Candidatus «Neoehrlichia mikurensis» was determined

CHARACTERISTICS OF THE BAIKAL SUBTYPE OF TICK-BORNE ENCEPHALITIS VIRUS CIRCULATING IN EASTERN SIBERIA

Background. During the study of the genetic variability of the tick-borne encephalitis virus (TBEV) in Eastern Siberia, a group of 22  strains with a unique genetic structure significantly different from all  known TBEV subtypes was identified. This TBEV variant was  tentatively called “group 886”. Therefore, for this original TBEV  variant it was necessary to study the genetic, biological properties of the “group 886” strains, clarify its TBEV taxonomic status, its range, evolutionary history, etc.Aim. The generalization of the currently available data on genetic and biological properties of TBEV “886” group.Materials and methods. The genetic structure of “group 886” strains was studied by the complex of molecular-genetic methods (MHNA, sequencing of fragments or the complete genome).Results. It was shown that “group 886” strains form a separate cluster on phylogenetic tree, and the level of genetic differences  from other genotypes is more than 12 %. It was defined that this  TBEV variant has its own area (Irkutsk region, Republic of Buryatia,  Trans-Baikal region, Northern Mongolia). Its ecological connection  with all links of the transmissive chain (ixodid ticks, small mammals,  human), participation in human pathology, stability and duration of  circulation in the Baikal region, individual evolutionary history  were proved. Some phenotypic characteristics of the “group 886” strains were considered.Conclusion. The presented data testify to the validity of the “886 group” isolation as an independent genetic type. Taking into account  the geographical distribution of this TBEV genotype, we propose to assign it the name “Baikal genotype/subtype”

The waking brain: an update

Wakefulness and consciousness depend on perturbation of the cortical soliloquy. Ascending activation of the cerebral cortex is characteristic for both waking and paradoxical (REM) sleep. These evolutionary conserved activating systems build a network in the brainstem, midbrain, and diencephalon that contains the neurotransmitters and neuromodulators glutamate, histamine, acetylcholine, the catecholamines, serotonin, and some neuropeptides orchestrating the different behavioral states. Inhibition of these waking systems by GABAergic neurons allows sleep. Over the past decades, a prominent role became evident for the histaminergic and the orexinergic neurons as a hypothalamic waking center

From sleep spindles of natural sleep to spike and wave discharges of typical absence seizures: is the hypothesis still valid?

The temporal coincidence of sleep spindles and spike-and-wave discharges (SWDs) in patients with idiopathic generalized epilepsies, together with the transformation of spindles into SWDs following intramuscular injection of the weak GABAA receptor (GABAAR) antagonist, penicillin, in an experimental model, brought about the view that SWDs may represent ‘perverted’ sleep spindles. Over the last 20 years, this hypothesis has received considerable support, in particular by in vitro studies of thalamic oscillations following pharmacological/genetic manipulations of GABAARs. However, from a critical appraisal of the evidence in absence epilepsy patients and well-established models of absence epilepsy it emerges that SWDs can occur as frequently during wakefulness as during sleep, with their preferential occurrence in either one of these behavioural states often being patient dependent. Moreover, whereas the EEG expression of both SWDs and sleep spindles requires the integrity of the entire cortico-thalamo-cortical network, SWDs initiates in cortex while sleep spindles in thalamus. Furthermore, the hypothesis of a reduction in GABAAR function across the entire cortico-thalamo-cortical network as the basis for the transformation of sleep spindles into SWDs is no longer tenable. In fact, while a decreased GABAAR function may be present in some cortical layers and in the reticular thalamic nucleus, both phasic and tonic GABAAR inhibitions of thalamo-cortical neurons are either unchanged or increased in this epileptic phenotype. In summary, these differences between SWDs and sleep spindles question the view that the EEG hallmark of absence seizures results from a transformation of this EEG oscillation of natural sleep