scholarly journals BIOFILM FORMATION BY YERSINIA PESTIS STRAINS OF THE MAIN AND NON- MAIN SUBSPECIES FROM NATURAL PLAGUE FOCI OF CENTRAL ASIA IN THE BODY OF XENOPSYLLA CHEOPIS FLEAS

2020 ◽  
pp. 32-38
Author(s):  
L.P. Bazanova ◽  
◽  
E.G. Tokmakova ◽  
G.A. Voronova ◽  
◽  
...  
Keyword(s):  
Central Asia ◽  
Yersinia Pestis ◽  
Biofilm Formation ◽  
The Body ◽  
Aggregation Index ◽  
Xenopsylla Cheopis ◽  
Blood Sucking ◽  
Central Asian ◽  
Natural Foci

The ability to form biofilms (“bacterial lumps” and “blocks”) by strains of different subspecies of Y. pestis in the body of the flea X. cheopis was studied. It was found that strains of the main subspecies form a biofilm almost three times more often than strains of the non-main subspecies – altaica and ulegeica (14.8±2.50 vs. 5.4±1.10). These differences were mainly due to the formation of “blocks” (9.2±1.66 vs. 1.6±0.45), rather than “bacterial lumps” (5.6±1.40 vs. 3.8±0.83). For X. cheopis fleas, infection with strains of the main subspecies in most cases leads to the predominance of massive forms of biofilm – “blocks” – aggregation index >1. When infecting with non-main subspecies pathogen from Central Asian natural foci, the persistence of the microbe in X. cheopis fleas usually occurs in the form of “lumps” and the aggregation index does not exceed 1. The success of transmission by fleas of this species is ensured not by the total number of blocked individuals, but by their presence and, accordingly, by probable blood-sucking during feeding.

scholarly journals POPULATIONS OF THE MAJOR CARRIER RHOMBOMYS OPIMUS, VECTORS OF XENOPSYLLA FLEAS AND THE CAUSATIVE AGENT OF YERSINIA PESTIS IN THE CENTRAL ASIAN DESERT NATURAL FOCUS OF PLAGUE

THE BULLETIN ◽  
2021 ◽  
Vol 389 (1) ◽  
pp. 26-34
Author(s):  
B. Atshabar ◽  
S.T. Nurtazhin ◽  
A. Shevtsov ◽  
E.M. Ramankulov ◽  
Z. Sayakova ◽  
...  
Keyword(s):  
Central Asia ◽  
Yersinia Pestis ◽  
Natural Focus ◽  
Great Gerbil ◽  
Central Asian ◽  
Natural Foci ◽  
Repertoire Diversity ◽  
Rhombomys Opimus ◽  
Major Carrier ◽  
Environmental Isolation

In the Central Asia desert natural focus of plague, the major carrier of the Yersinia pestis agent is the great gerbil Rhombomys opimus, and its vectors include fleas of the Xenopsylla genus. Phenotypical and genotypical properties of the R. opimus populations, Xenopsylla fleas and Yersinia pestis strains have been studied in the Central Asia desert natural focus of plague. Phenotypic distinctions and population discreteness have been identified in R. opimus on the cytochrome b gene of the mitochondrial genome from three autonomous plague foci: Pre-Balkhash, Betpakdala and Pre-Ustyurt. Phenotypic distinctions have been found in Xenopsylla fleas in the Central Asia desert natural focus of plague, and the genotype of X. gerbilli minax fleas on the Cox2 gene of the mitochondrial DNA; these had been captured in the Betpakdala autonomous focus. The repertoire diversity in phenotypical properties of Y. pestis strains from different natural foci of plague has been demonstrated, and population discreteness of Y. pestis strains has been determined using the next-generation sequencing method for single nucleotide polymorphism genes. Results of the study suggest that geographical and environmental isolation and natural selection have led to heterogeneity in the three populations of the great gerbil, vector fleas and Y. pestis.

Influence of Temperature on Development of Yersinia pestis Foregut Blockage in Xenopsylla cheopis (Siphonaptera: Pulicidae) and Oropsylla montana (Siphonaptera: Ceratophyllidae)

2020 ◽  
Vol 57 (6) ◽  
pp. 1997-2001
Author(s):  
Athena Lemon ◽  
Nathan Cherzan ◽  
Viveka Vadyvaloo
Keyword(s):  
Yersinia Pestis ◽  
Survival Rates ◽  
Bacterial Pathogen ◽  
Flea Species ◽  
Relevant Parameter ◽  
Wild Rodents ◽  
Xenopsylla Cheopis ◽  
Blood Sucking ◽  
Geographical Regions ◽  
Oropsylla Montana

Abstract Plague, caused by the flea-transmitted bacterial pathogen Yersinia pestis, is primarily a disease of wild rodents distributed in temperate and tropical zones worldwide. The ability of Y. pestis to develop a biofilm blockage that obstructs the flea foregut proventriculus facilitates its efficient transmission through regurgitation into the host bite site during flea blood sucking. While it is known that temperature influences transmission, it is not well-known if blockage dynamics are similarly in accord with temperature. Here, we determine the influence of the biologically relevant temperatures, 10 and 21°C, on blockage development in flea species, Xenopsylla cheopis (Rothschild) and Oropsylla montana (Baker), respectively, characterized by geographical distribution as cosmopolitan, tropical or endemic, temperate. We find that both species exhibit delayed development of blockage at 10°C. In Y. pestis infected X. cheopis, this is accompanied by significantly lower survival rates and slightly decreased blockage rates, even though these fleas maintain similar rates of persistent infection as at 21°C. Conversely, irrespective of infection status, O. montana withstand 21 and 10°C similarly well and show significant infection rate increases and slightly greater blocking rates at 10 versus 21°C, emphasizing that cooler temperatures are favorable for Y. pestis transmission from this species. These findings assert that temperature is a relevant parameter to consider in assessing flea transmission efficiency in distinct flea species residing in diverse geographical regions that host endemic plague foci. This is important to predict behavioral dynamics of plague regarding epizootic outbreaks and enzootic maintenance and improve timeous implementation of flea control programs.

scholarly journals INFLUENCE OF YERSINIA PESTIS PLASMID CONTENT ON BIOFILM FORMATION IN FLEAS WITH DIFFERENT VECTOR ACTIVITY

2018 ◽  
pp. 76-83
Author(s):  
L. P. Bazanova ◽  
E. G. Tokmakova ◽  
G. A. Voronova ◽  
S. V. Balakhonov
Keyword(s):  
Yersinia Pestis ◽  
Biofilm Formation ◽  
Death Rate ◽  
Plasmid Content ◽  
Xenopsylla Cheopis ◽  
Highly Active ◽  
Individual Number ◽  
Vector Activity ◽  
The Individual

Aim. Influence of the plague agent plasmid content on biofilm formation in vivo and death rate of fleas-vectors with different vector activity in experiment were analyzed. Materials and methods. Three Yersinia pestis strains: virulent I-3230 (pYT, pYV, pYP) and I-2638 (pYT, pYV, pYP, pTP 33), and its selected avirulent isogenic clone I-3480 lacking two plasmids (pYV, pYP) were used. Three species of fleas were artificially infected: 477 individuals of Xenopsylla cheopis (a highly active vector), 441 - Citellophilus tesquorum (an active vector), 519 - Frontopsylla lucu-lenta (a low-active vector). The peculiarities of Y. pestis biofilm formation in fleas were estimated by a portion of individuals with bacterial «conglomerates» and «blocks» for a feeding. Death rate of the insects was defined by the percent of the dead fleas at each feeding. Results. All three flea species infected by Y. pestis strains carrying an additional plasmid pTP33 (I-2638 and I-3480) demonstrated the increase of the individual number with various biofilm forms in comparison with the three-plasmid strain I-3230. In X. cheopis it occurred due to the blocked insects, in C. tesquo-rum - mainly due to the fleas containing «conglomerates», in F. luculenta it was completely connected with ectoparasites with «conglomerates». A share of X. cheopis and C. tesquorum died at a feeding was higher in ectoparasites infected with I-3230 strain and F. luculenta - infected by I-2638. Conclusion. Y. pestis strains possessing an additional replicon pTP33 formed a biofilm in the infected insects more often and larger size than a classical three-plasmid variant. Influence of the strain plasmid content on death rate of the infected fleas depended on a vector species.

scholarly journals Serotype Differences and Lack of Biofilm Formation Characterize Yersinia pseudotuberculosis Infection of the Xenopsylla cheopis Flea Vector of Yersinia pestis

2006 ◽  
Vol 188 (3) ◽  
pp. 1113-1119 ◽  
Author(s):  
David L. Erickson ◽  
Clayton O. Jarrett ◽  
Brendan W. Wren ◽  
B. Joseph Hinnebusch
Keyword(s):  
Yersinia Pestis ◽  
Biofilm Formation ◽  
Yersinia Pseudotuberculosis ◽  
Ex Vivo ◽  
Blood Feeding ◽  
Genetic Change ◽  
Xenopsylla Cheopis ◽  
C Elegans ◽  
Transmissible Infection

ABSTRACT Yersinia pestis, the agent of plague, is usually transmitted by fleas. To produce a transmissible infection, Y. pestis colonizes the flea midgut and forms a biofilm in the proventricular valve, which blocks normal blood feeding. The enteropathogen Yersinia pseudotuberculosis, from which Y. pestis recently evolved, is not transmitted by fleas. However, both Y. pestis and Y. pseudotuberculosis form biofilms that adhere to the external mouthparts and block feeding of Caenorhabditis elegans nematodes, which has been proposed as a model of Y. pestis-flea interactions. We compared the ability of Y. pestis and Y. pseudotuberculosis to infect the rat flea Xenopsylla cheopis and to produce biofilms in the flea and in vitro. Five of 18 Y. pseudotuberculosis strains, encompassing seven serotypes, including all three serotype O3 strains tested, were unable to stably colonize the flea midgut. The other strains persisted in the flea midgut for 4 weeks but did not increase in numbers, and none of the 18 strains colonized the proventriculus or produced a biofilm in the flea. Y. pseudotuberculosis strains also varied greatly in their ability to produce biofilms in vitro, but there was no correlation between biofilm phenotype in vitro or on the surface of C. elegans and the ability to colonize or block fleas. Our results support a model in which a genetic change in the Y. pseudotuberculosis progenitor of Y. pestis extended its pre-existing ex vivo biofilm-forming ability to the flea gut environment, thus enabling proventricular blockage and efficient flea-borne transmission.

scholarly journals Traveler Motivation and Destination Loyalty: Visiting Sacred Places in Central Asia

2020 ◽  
Vol 2 (1) ◽  
pp. 1-14
Author(s):  
Liza Rybina ◽  
Timothy J. Lee
Keyword(s):  
Central Asia ◽  
Significant Relationship ◽  
Mixed Methods Research ◽  
The Body ◽  
Structured Interviews ◽  
Sacred Places ◽  
Sacred Sites ◽  
Destination Loyalty ◽  
Sacred Spaces ◽  
Central Asian

Visiting sacred spaces is becoming a growing trend in tourism in the Central Asian region. Sacred sites are said to have the power to heal the body, enlighten the mind, and inspire the heart. This study explored the motivations for visiting sacred spaces among tourists from three Central Asian countries—Kazakhstan, Kyrgyzstan, and Uzbekistan. The study used a sequential mixed methods research design. In the first stage, a general list of motivations was produced, based on the analysis of 14 semi-structured interviews. The second stage quantitative survey was conducted with a sample of 211 tourists from Central Asia. Data collection took place during tours to sacred sites in the city of Turkestan in South Kazakhstan. Data analysis included descriptive statistics, factor analysis, and regression analysis. The relationships between motivation factors and destination loyalty were tested. The results show that among the five motivational factors identified in this study, only three (Spiritual and Religious Motives, Cultural and Historical Motives, and Wellness and Healing) have a significant relationship with sacred site destination loyalty. The remaining two factors (Nature, Fun, and Social Contact) have not been proven to have a significant relationship with destination loyalty. The study adds value to the literature on traveling to religious sites, especially those in formerly atheist countries, and provides recommendations to practitioners and policymakers to enable them to develop a niche tourism area by segmenting tourists’ motivations and destination loyalty in their sacred places. It also contributes to the diversification of tourism products in those destinations that have historical religious heritage resources.

Problems of military-political interaction between the countries of the West and Central Asia at the turn of the XX–XXI centuries

2020 ◽  
pp. 27-33
Author(s):  
Boris G. Koybaev
Keyword(s):  
Central Asia ◽  
The United States ◽  
Military Bases ◽  
Islamic State ◽  
The West ◽  
Regional Environment ◽  
Western Influence ◽  
Central Asian ◽  
Political Interaction ◽  
The Military

Central Asia in recent history is a vast region with five Muslim States-new actors in modern international relations. The countries of Central Asia, having become sovereign States, at the turn of the XX–XXI centuries are trying to peaceful interaction not only with their underdeveloped neighbors, but also with the far-off prosperous West. At the same time, the United States and Western European countries, in their centrosilic ambitions, seek to increase their military and political presence in Central Asia and use the military bases of the region’s States as a springboard for supplying their troops during anti-terrorist and other operations. With the active support of the West, the Central Asian States were accepted as members of the United Nations. For monitoring and exerting diplomatic influence on the regional environment, the administration of the President of the Russian Federation H. W. Bush established U.S. embassies in all Central Asian States. Turkey, a NATO member and secular Islamic state, was used as a lever of indirect Western influence over Central Asian governments, and its model of successful development was presented as an example to follow.

Sedelnikovaea baicalensis (Lecanoraceae) — new lichen genus and species for Europe

2018 ◽  
Vol 52 (2) ◽  
pp. 407-416
Author(s):  
T. V. Makryi
Keyword(s):  
Central Asia ◽  
Lichen Species ◽  
Significant Part ◽  
The Urals ◽  
Southern Siberia ◽  
Central Asian ◽  
Northeastern Siberia ◽  
Mountain Belts ◽  
First Time ◽  
Vast Range

Sedelnikovaea baicalensis, the Siberian-Central Asian lichen species, is recorded for the first time for Europe. Based on all the known localities, including those first-time reported from Baikal Siberia, the peculiarities of the ecology and distribution of this species are discussed, the map of its distribution is provided. It is concluded that the species was erroneously considered earlier as a Central Asian endemic. The center of the present range of this lichen is the steppes of Southern Siberia and Mongolia. Assumptions are made that S. baicalensis is relatively young (Paleogene-Neogene) species otherwise it would have a vast range extending beyond Asia, and also that the Yakut locations of this species indicate that in the Pleistocene its range was wider and covered a significant part of the Northeastern Siberia but later underwent regression. Based on the fact that in the mountains of Central Asia the species is found only in the upper mountain belts, it is proposed to characterize it as «cryo-arid xerophyte» in contrast to «arid xerophytes». A conclusion is made that the presence of extensive disjunctions of S. baicalensis range between the Southern Pre-Urals and the Altai-Sayan Mountains or the Mountains of Central Asia is unlikely; the lichen is most likely to occur in the Urals and most of Kazakhstan.

Language as a Factor in the New Identity Formation (Illustrated by Central Asian States)

2019 ◽  
pp. 175-187
Author(s):  
Tetiana Liashenko
Keyword(s):  
Central Asia ◽  
Russian Federation ◽  
Russian Language ◽  
Political Space ◽  
Sources Of Information ◽  
Positive Image ◽  
Central Asian ◽  
The Russian Federation ◽  
National Languages ◽  
The Russian Language

Attempts to build a “Russian world” within the former Soviet republics of Central Asia by introducing an idea of a single linguistic, cultural and political space with the Russian Federation are studied in the article. The threats to the Central Asian countries’ information space are analyzed. The data on gradual changing of orientations of the Central Asian states’ citizens when choosing sources of information is provided. It is concluded that the technologies of the Russian Federation’s propaganda in Central Asia are aimed primarily at the formation of the president of Russia positive image among the widest possible groups of population. Attempts to push so-called “the Russian world”, which already jeopardize global peaceful balance, are grounded, in particular, on a widespread use of the Russian language within the territories of the former USSR that serves to propagate an idea of a single linguistic, cultural and political space. At the same time, a revival and development of national languages and cultures are intensively ongoing in all new independent states. It provokes a confrontation that often causes points of tension and conflicts. A large number of the Russian media, including federal state editions, TV channels. the Sputnik news agency etc. operates in Central Asian information space. Using own controlled media, the Kremlin seeks to convince the Central Asian states’ citizens that the Russia’s foreign policy is a right one, as well as to form a positive image of Russia and president Putin as a politician who is capable to ensure stability and security in the Central Asian region. The Russian Federation pays a special attention to Eastern Kazakhstan, where a large number of ethnic Russians is concentrated. Kazakhstan has much in common with Ukraine on its ethnic population composition, economic situation and geographical proximity to Russia. As in Ukraine, the ethnic Russians make up about 1/5 of the population in Kazakhstan, meanwhile the Russian language is widely used in all spheres. Russia calls its initiative a “humanitarian project”, but there is no doubt that the Kremlin is fighting for minds of younger generation, trying to impose own culture and values on young people. Recently, while alternative sources of information have been spreading, more and more Central Asian habitants opt for online information in their national languages, considering Russianspeaking news resources to be a propaganda.

New European Union strategy for Central Asia

2020 ◽  
pp. 72-79
Author(s):  
S. Gavrilova
Keyword(s):  
European Union ◽  
Central Asia ◽  
Economic Cooperation ◽  
The European Union ◽  
Asian Countries ◽  
Energy Potential ◽  
High Importance ◽  
Central Asian ◽  
New Strategy ◽  
Central Asian Countries

For several decades, the European Union has been steadily increasing its presence in Central Asian countries. The EU's interests in the region are due to a number of reasons, including the desire to expand its influence in the Central Asian countries, the high importance of the region as a transit corridor between Europe and China, the prospects for economic cooperation, and the importance of the region's energy potential. In May 2019 The European Union has presented a new Strategy for Central Asia, designed to intensify cooperation in a number of areas of interaction. The new strategy is aimed at both implementing these interests and expanding cooperation in a number of other areas.

ВНЕШНЕПОЛИТИЧЕСКАЯ СИТУАЦИЯ В ЦЕНТРАЛЬНОЙ АЗИИ: В КОНТЕКСТЕ МЕЖДУНАРОДНЫХ ОТНОШЕНИЙ И НОВЫХ ТЕНДЕНЦИЙ В МИРОВОЙ ПОЛИТИКЕ

2020 ◽  
Author(s):  
Токтобек Рыскулов
Keyword(s):  
Central Asia ◽  
Transnational Corporation ◽  
World Politics ◽  
Energy Resources ◽  
Gas Oil ◽  
Political Events ◽  
Central Asian ◽  
The Usa ◽  
The Russian Federation ◽  
Near Future

Аннотация. В статье очерчено геополитическое и геостратегическое положение ЦА. Охарактеризована внешнеполитическая ситуация в ЦА в контексте новых тенденций в мировой политике. Показаны основные интересы и политические тренды РФ, США, КНР по отношения к государствам ЦА. Отмечено, что современная Центральная Азия, притягивает к себе все большее внимание внешних игроков. Объяснение кроется в том, что Центральная Азия обладает не только удобным геополитическим и выгодным геостратегическим положением, но и большим количеством природных ресурсов. Анализируя современные российско-китайские отношения приходим к мысли, что не все так безоблачно во взаимоотношениях двух государств, ведь еще никто не опроверг постулат о постоянных интересах государств и о непостоянстве друзей. В недалеком будущем конкуренция за энергоресурсы (газ, нефть) ЦА приведет к обострению отношений, к конфликту интересов России и Китая, практически это политическая аксиома. Готовы ли государства ЦА и России к такому сценарию политических событий? Ключевые слова: Центральна Азия, геополитика и геостратегия. Большая Игра, РФ, США, КНР. ЕАЭС, Большая Центральная Азия, ТНК, терроризм, экстремизм. Аннотация. Макалада геосаясий жана геостратегиялык абалдары чийилген. Борбордук Азиядагы тышкы саясий кырдаал дүйнөлүк саясаттагы жаңы тенденциялардын контекстинде мүнөздөлдү. БА мамлекеттеринин мамилелери боюнча РФ, АКШ, КЭР негизги кызыкчылыктары жана саясий тренддери көрсөтүлдү. Учурдагы Борбордук Азия тышкы оюнчулардын көбүрөөк көңүлүн өзүнө тартып жаткандыгы байкалган. Түшүндүрмө берүү, Борбордук Азия ыңгайлуу геосаясий жана пайдалуу геостратегиялык абалга гана ээ болбостон, көптөгөн жаратылыш ресурстарына ээ. Анализируя заманбап российско-кытай мамилелери приходим карата ойлорун, бул эмес баары эле безоблачно өз ара мамилелеринде эки мамлекеттин, анткени дагы эч ким опроверг постулат жөнүндө туруктуу кызыкчылыгында мамлекеттердин жөнүндө жана непостоянстве досторунун. Жакынкы келечекте ба энергия ресурстары үчүн атаандаштык (газ, мунай) Россия жана Кытайдын таламдарынын кагылышына, мамилелердин күчөшүнө алып келет, бул иш жүзүндө саясий аксиома. Борбордук Азия жана Орусия мамлекеттери мындай жагдайды саясий окуяларга даярбы? Түйүндүү сөздөр: Борбор Азия, геополитика жана геостратегия. Чоң оюн, РФ, АКШ, КЭР. ЕАЭС, Чоң Борбордук Азия, ТНК, терроризм, экстремизм. Annotation. The article outlines the geopolitical and geostrategic position of Central Asia. The article describes the foreign policy situation in Central Asia in the context of new trends in world politics. The main interests and political trends of the Russian Federation, the USA, China in relation to the Central Asian States are shown. It is noted that modern Central Asia attracts more and more attention of external players. The explanation lies in the fact that Central Asia has not only a convenient geopolitical and advantageous geostrategic position, but also a large number of natural resources. Analyzing the current Russian-Chinese relations, we come to the conclusion that not everything is so cloudless in the relations between the two States, because no one has yet refuted the postulate about the permanent interests of States and the impermanence of friends. In the near future, competition for energy resources (gas, oil) in Central Asia will lead to an aggravation of relations, to a conflict of interests between Russia and China, this is practically a political axiom. Are the Central Asian and Russian States ready for such a scenario of political events? Key words: Central Asia, geopolitics & geostrategy. Big Game, the RF, the USA, the CPR. EAEC, Big Central Asia, Transnational Corporation, terrorism, extremism

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