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At least 19 recordsLinked to original sources
PubMed2000

Integrated Paleomagnetism and U-Pb Geochronology of Mafic Dikes of the Eastern Anabar Shield Region, Siberia: Implications for Mesoproterozoic Paleolatitude of Siberia and Comparison with Laurentia.

This article reports the first joint paleomagnetic and U-Pb geochronologic study of Precambrian diabase dikes in the Anabar Shield and adjacent Riphean cover of Siberia. It was undertaken to allow comparison with similar published studies in Laurentia and to test Proterozoic reconstructions of Siberia and Laurentia. An east-trending Kuonamka dike yielded a provisional U-Pb baddeleyite emplacement age of 1503+/-5 Ma and a virtual geomagnetic pole at 16 degrees S, 221 degrees E (dm=17&j0;, dp=10&j0;). A paleomagnetic pole at 6 degrees N, 234 degrees E (dm=28&j0;, dp=14&j0;) was obtained from five Kuonamka dikes. An east-southeast-trending Chieress dike yielded a U-Pb baddeleyite emplacement age of 1384+/-2 Ma and a virtual geomagnetic pole at 4 degrees N, 258 degrees E (dm=9&j0;, dp=5&j0;). Kuonamka and Chieress poles are interpreted to be primary but do not average out secular variation. Assuming that the Siberian Plate has remained intact since the Mesoproterozoic, except for mid-Paleozoic opening of the Viljuy Rift, then the above results indicate that the Siberian Plate was in low latitudes at ca. 1503 and 1384 Ma, broadly similar to low latitudes determined for Laurentia from well-dated paleopoles at 1460-1420, 1320-1290, and 1267 Ma. This would allow Laurentia and Siberia to have been attached in the Mesoproterozoic, as suggested in several recent studies based on geological criteria. However, because paleomagnetic results from the Anabar Shield region do not average out secular variation and the ages of poles from Siberia and Laurentia are not well matched, it is not yet possible to distinguish between these reconstructions or to rule out other configurations that also maintain the two cratons at low paleolatitudes.

Journal Article↗
PubMed1990

Participation of Indo-European tribes in ethnogeny of the mongoloid population of Siberia: analysis of the HLA antigen distribution in mongoloids of Siberia.

Three hundred forty-three Yakuts (mongoloids of central Asian type living in Siberia) were tested for HLA-A, -B, and -C loci. The HLA antigen distribution corresponds on the whole to a mongoloid population with high frequency of the HLA-A9, -B15, and -B40 antigens (phenotype frequencies .533, .367, and .405, respectively). At the same time a strikingly high frequency for the "Indo-European" HLA-A1 antigen (phenotype frequency .282) was detected, which in Yakuts is found exclusively with HLA-B17 (haplotype frequency x 1,000 = 87.0; linkage disequilibrium value x 1,000 = 63.8). The present paper deals with a new hypothesis of the Yakut ethnogenesis according to which ancient Aryan tribes formed the substratum which was later assimilated by the mongoloid and Turkic populations. Another hypothesis that I have advanced argues that from analysis of the HLA system the ancient Aryans formed, a local group within the Indo-European entity, with high frequency for HLA-A1 and -B17 antigens and for the HLA-A1,B17 haplotype and with a complete absence of or very low frequency for the HLA-B8 antigen and for the HLA-A1,B8 haplotype. Significant linkage disequilibrium, as it is found in Indians and Yakuts, etc., could have resulted from mixing of the Aryans with non-Indo-European tribes. No significant linkage disequilibrium between A1 and B8 characteristic of the European caucasoids was produced in the mixing.

Asian People↗
PubMed2000

Precursor genes of future pandemic influenza viruses are perpetuated in ducks nesting in Siberia.

Influenza A viruses of different subtypes were isolated from fecal samples of ducks in their nesting areas in Siberia in summer from 1996 to 1998. Phylogenetic analysis of the NP genes of the isolates in Siberia and those in Hokkaido, Japan on their flyway of migration from Siberia to the south in autumn revealed that they belong to the Eurasian lineage of avian influenza viruses. It is noted that the genes of the isolates in Siberia are closely related to those of H5N1 influenza virus strains isolated from chickens and humans in Hong Kong in 1997 as well as to those of isolates from domestic birds in southern China. The results indicate that influenza viruses perpetuated in ducks nesting in Siberia should have contributed genes in the emergence of the H5N1 virus in Hong Kong. Vaccine prepared from avirulent A/duck/Hokkaido/4/96 (H5N3) influenza virus was potent enough to protect mice from challenge with lethal dose of the pathogenic H5N1 virus [19]. Intensive surveillance study of aquatic birds especially in Siberia is, therefore, stressed to provide information on the future pandemic influenza virus strains and for vaccine preparation.

Animals↗
PubMed1996

Integrated chronostratigraphy of Proterozoic-Cambrian boundary beds in the western Anabar region, northern Siberia.

Carbonate-rich sedimentary rocks of the western Anabar region, northern Siberia, preserve an exceptional record of evolutionary and biogeochemical events near the Proterozoic/Cambrian boundary. Sedimentologically, the boundary succession can be divided into three sequences representing successive episodes of late transgressive to early highstand deposition; four parasequences are recognized in the sequence corresponding lithostratigraphically to the Manykal Formation. Small shelly fossils are abundant and include many taxa that also occur in standard sections of southeastern Siberia. Despite this coincidence of faunal elements, biostratigraphic correlations between the two regions have been controversial because numerous species that first appear at or immediately above the basal Tommotian boundary in southeastern sections have first appearances scattered through more than thirty metres of section in the western Anabar. Carbon- and Sr-isotopic data on petrographically and geochemically screened samples collected at one- to two-metre intervals in a section along the Kotuikan River, favour correlation of the Staraya Reckha Formation and most of the overlying Manykai Formation with sub-Tommotian carbonates in southeastern Siberia. In contrast, isotopic data suggest that the uppermost Manykai Formation and the basal 26 m of the unconformably overlying Medvezhya Formation may have no equivalent in the southeast; they appear to provide a sedimentary and palaeontological record of an evolutionarily significant time interval represented in southeastern Siberia only by the sub-Tommotian unconformity. Correlations with radiometrically dated horizons in the Olenek and Kharaulakh regions of northern Siberia suggest that this interval lasted approximately three to six million years, during which essentially all 'basal Tommotian' small shelly fossils evolved.

Animals↗
PubMed1994

Virologic and genetic studies relate Amerind origins to the indigenous people of the Mongolia/Manchuria/southeastern Siberia region.

A commonly held theory is that the first wave of migrants into the New World was derivative from the ethnic groups then inhibiting eastern Siberia. However, these ethnic groups lack a mtDNA haplogroup (B) that is well represented in Amerindian tribes. Also, the time depth of the other three mtDNA haplogroups found in Amerindians (A, C, and D) appears to be greater in the Amerindians than in the eastern Siberian ethnic groups. In this communication we demonstrate that the human T-cell lymphotrophic virus type II, present in 11 of the 38 Amerindian tribes thus far examined, is not present in any of the 10 ethnic groups of eastern Siberia that we have studied. However, the virus has just been reported in the indigenous population of Mongolia, and mtDNA haplogroup B is also represented in this region. On the basis of these facts, we propose that the ancestors of the first migrants to the New World were not derived from north and central Siberia but from populations to the south, inhabiting the regions of Mongolia, Manchuria, and/or the extreme southeastern tip of Siberia.

Central America↗
PubMed1995

Sizing up the sub-Tommotian unconformity in Siberia.

Sedimentary rocks in the western Anabar region, northwestern Siberia, preserve an exceptional record of evolution and biogeochemical events near the Proterozoic-Cambrian boundary. Carbon isotopic data on petrographically and geochemically screened samples collected at 1 to 2 m intervals support correlation of the lower Anabar succession (Staraya Reckha and lower Manykai Formations) with sub-Tommotian carbonates of the Ust'-Yu-doma Formation in southeastern Siberia. In contrast, the upper Manykai and most of the overlying Medvezhya Formation appear to preserve a sedimentary and paleontological record of an evolutionary important time interval represented in southeastern Siberia only by the sub-Tommotian unconformity. Correlation of the Anabar section with other northern Siberian successions that contain well-dated volcanic rocks permits the estimate that the sub-Tommotian unconformity in southeastern Siberia spans approximately 3 to 6 m.y. Diverse small shelly fossils (but not archaeocyathans) previously thought to mark the base of the Tommotian Stage evolved sequentially throughout this earlier interval.

Animals↗
PubMed2004

[Differentiation of the mitochondrial subhaplogroup U4 in the populations of Eastern Europe, Ural, and Western Siberia: implication to the genetic history of the Uralic populations].

Phylogenetic relationships between the sequences of the mitochondrial DNA (mtDNA) hypervariable segment 1, belonging to subhaplogroup U4, were examined in the populations of Eastern Europe, Ural, and Northwest Siberia. It was shown that the frequency of subhaplogroup U4, as well as its proportion in the U-component of the gene pools, increased eastwards, reaching maximum values in the populations of Northwest Siberia. Phylogenetic analysis it was showed that the appearance of specific U4-lineage (16113C-16356-16362) in the ancestors of Mansi was most likely caused by its divergence from the East European cluster 16356-16362 in the Late Upper Paleolithic (18566 +/- 12915 years before present). Other U4 mtDNA lineages (16189-16356 and 16311-16356), typical mostly of the indigenous populations of Northwest Siberia (Mansi, Nganasans, and Kets) may have formed during the Neolithic-early Bronze Age (6055 +/- 3599 years before present, on average). It seems likely that the isolation of ancient populations inhabiting the region between the Ob' and Yenisei rivers was the key factor, providing the appearance of the unique Caucasoid mtDNA lineages in their gene pools. These results were consistent with the traditional point of view on the mixed origin of the Finno-Ugric populations of the Volga-Ural region and West Siberia, resulted from the genetic relationships between the populations of Europe and Asia.

DNA, Mitochondrial↗
PubMed1998

[Role of cryoglobulinemia in rheumatic diseases as illustrated by citizens of Moscow (resident population) and Tynda (migrants to Siberia)].

AIM: To determine occurrence of cryoglobulinemia (CGE) in residents of Moscow with various rheumatic diseases and healthy subjects, in Tynda population (migrants to Siberia) with rheumatic arthritis (RA) and healthy ones. MATERIALS AND METHODS: CG screening was performed according to the WHO recommendations among 243 rheumatic patients from Moscow, 500 healthy subjects living in Moscow, 72 RA patients from Siberia and 1750 healthy Siberia migrants. RESULTS: CGE occurred more frequently among Moscovites with SLE and RA (28 and 19%, respectively). In RA Siberians CGE was present in 52%. In healthy Siberians CGE occurred in 8.4% of the examinees, in Moscovites it was extremely rare. In all the examinees CGE was associated with cryoglobulinemia syndrome. SLE and RA Moscovites had mixed CGE with monoclonal components (type II), RA Siberial migrants had CGE type II and III (mixed polyclonal). CONCLUSION: The study of CGE incidence in healthy migrants to Siberia with different duration of residence, measurements of metal ions in RA Siberians with and without CGE in the serum, blood cells and cryoprecipitates provided the authors with information for a new hypothesis of CGE origin and design of new policy of treating CGE.

Adolescent↗
PubMed1999

Collateral relatives of American Indians among the Bronze Age populations of Siberia?

Nonmetric and metric traits were studied in cranial series representing prehistoric and modern populations of America and Siberia. Frequencies of the infraorbital pattern type II (longitudinal infraorbital suture overlaid by the zygomatic bone) are universally lower in Amerindians than in Siberians. The os japonicum posterior trace, too, is much less frequent in America than in Siberia. The only two Siberian groups with an almost Amerindian combination are late third to early second millennium BC populations from Okunev and Sopka, southern Siberia. The multivariate analysis of five nonmetric facial traits and ten facial measurements in 15 cranial series reveals two independent tendencies. One of them shows a contrast between prehistoric Siberian Caucasoids and modern Siberian Mongoloids; the second one sets Amerindians apart from others. Prehistoric people who lived west of Lake Baikal and modern Uralic speakers are intermediate between Siberian Caucasoids and Siberian Mongoloids; Eskimos, Aleuts, and Chukchi are intermediate between Siberian Mongoloids and Amerindians; and Okunev and Sopka are intermediate between Siberian Caucasoids and Amerindians. Our results suggest that people of Okunev and Sopka are collateral relatives of Amerindians with some Caucasoid admixture.

Adult↗
PubMed2004

Hepatitis B virus genotype D strains from Estonia share sequence similarity with strains from Siberia and may specify ayw4.

The genotypes and subtypes of 205 HBV isolates collected during 1989-2002 in Estonia and 14 other regions of the former USSR were determined by sequencing and phylogenetic analysis of the S gene. The in Europe prevailing genotypes, A and D, were also circulating in the whole territory of the former USSR including Estonia and accounted for 18.5 and 81% of the strains, respectively. All genotype A strains specified adw2, and a single genotype C strain specified adrq+. Most genotype D strains specified ayw3 and ayw2, although, three strains from Estonia and Siberia specified ayw4. Due to unique substitutions, Ser122 and Ala127, four strains could not be classified according to the subtype. One strain specifying ayw3 encoded Leu143 and Ala145 and was possibly an immune "escape" mutant. At phylogenetic analysis 93% of the Estonian genotype D strains belonged to a cluster specifying mainly ayw3 and were more similar to isolates from Siberia and the Far-East of Russia than to isolates originating from Central Russia which belonged to another cluster of strains specifying mainly ayw2. This pattern might be explained by part of the Estonian population, has roots east of European Russia, based on linguistic evidence. Eight dominant HBV strains represented by identical S gene sequences were identified, one within genotype A and seven within genotype D, three of which included isolates from Estonia and Siberia. Some of these strains were collected over a period of at least 13 years indicating there are genetically stable variants of HBV that remain conserved over decades.

Estonia↗
PubMed2003

Detection and typing of Borrelia burgdorferi sensu lato genospecies in Ixodes persulcatus ticks in West Siberia, Russia.

The prevalence of Borrelia burgdorferi sensu lato (s.l.) genospecies in West Siberia as well as in many other regions of Russia remains insufficiently investigated. In the present study a total of 151 adult female ticks Ixodes persulcatus Schulze, collected at three localities in eastern regions of West Siberia, where Lyme disease is endemic, were examined for the presence of the spirochete B. burgdorferi s.l. by polymerase chain reaction targeting the 23S-5S rRNA intergenic spacer regions. Spirochetal DNA was detected in on average 15.2+/-3.0% of the ticks examined. The infection rate of adult ticks with B. burgdorferi s.l. at various localities ranged from 8.6+/-3.4% to 29.0+/-7.6%, being greatest in the northernmost site studied and decreasing southwards. The restriction patterns obtained after MseI digestion of the 23S-5S rRNA intergenic spacer amplicons assigned 23 DNA samples to the following genomic groups: 19 to B. garinii (12 to group NT29 and seven to group 20047(T)), three to B. afzelii, and one to mixed B. afzelii and B. garinii NT29. We have not detected other genospecies, which were found in ticks in Europe, the Russian Far East and Japan. Thus, the ticks examined were associated only with two genospecies of Borrelia burgdorferi s.l. pathogenic to humans (B. garinii and B. afzelii), and B. garinii was the major genospecies infecting adult I. persulcatus in eastern regions of West Siberia.

Animals↗
PubMed1996

Tuberculosis in Siberia: 1. An epidemiological and microbiological assessment.

SETTING: Siberia, Russian Federation. OBJECTIVE: To assess the situation regarding tuberculosis as a paradigm for the Russian Federation. DESIGN: Data was obtained from official sources and through visits to dispensaries and hospitals in 1994. RESULTS: The downward trend in notifications of tuberculosis throughout Russia reversed in 1990/91, the rate increasing from 34/100,000 to 42.9/100,000 in 1993. Incidence rates are higher in Siberia, varying from approximately 43 to 108/100,000; prevalence is 250-300/100,000. The tuberculosis service is centralized and based on specialized polyclinics and dispensaries. An extensive surveillance system employs regular fluorography and tuberculin testing: half of the cases diagnosed are detected by fluorography, against 1% through contact tracing. Patients are classified principally on clinical and radiological grounds. Bacille Calmette-Guérin immunisation is performed at birth and at age 7, and again at 13, 21, and 28 years if Mantoux test is negative. Microscopy and culture services are organisationally separate, and direct comparison of smear and culture data is not possible. Drug resistance to isoniazid and streptomycin is probably high and resistance to rifampicin low, but data on susceptibility of isolates from new cases are not available. CONCLUSION: Tuberculosis is increasing in Siberia. Homelessness, unemployment and alcoholism are important factors, but concurrent human immunodeficiency virus (HIV) infection appears to be uncommon. Prisons probably form a significant reservoir of infectious cases.

Adult↗
PubMed2001

Seroprevalence of Helicobacter pylori infection in Siberia.

BACKGROUND: Despite many population-based epidemiological studies of Helicobacter pylori prevalence in different parts of the world, Russia still represents a 'blank spot' in this map. The aims of the present study were to evaluate the seroprevalence of H. pylori infection among the population of Siberia and to assess whether there is an association between abdominal symptoms and H. pylori positivity in our population. METHODS: Six hundred and forty-nine adults from five regions of Siberia and the Far East, and 79 children and adolescents from Novosibirsk participated in the study. Antibodies against H. pylori (IgG) were detected in serum using ELISA. RESULTS: The total percentage of infected adults varied from 70% to 92% depending on the region, and was somewhat lower in three populations living to the north of the 60th latitude compared with those under the 60th latitude. A lack of association was found between the presence of H. pylori and the gender, age and abdominal symptoms. Almost maximum prevalence of H. pylori infection occurred by 30 years of age with only a minor increase in older age groups. Half the children were infected with H. pylori by the age of 15. CONCLUSIONS: Helicobacter pylori infection is widespread among the Siberian populations with some trend in its prevalence to decrease northward. In Siberia age-specific prevalence rates of H. pylori infection are similar to those usual for developing countries.

Adolescent↗
PubMed2005

Mitochondrial DNA diversity in indigenous populations of the southern extent of Siberia, and the origins of Native American haplogroups.

In search of the ancestors of Native American mitochondrial DNA (mtDNA) haplogroups, we analyzed the mtDNA of 531 individuals from nine indigenous populations in Siberia. All mtDNAs were subjected to high-resolution RFLP analysis, sequencing of the control-region hypervariable segment I (HVS-I), and surveyed for additional polymorphic markers in the coding region. Furthermore, the mtDNAs selected according to haplogroup/subhaplogroup status were completely sequenced. Phylogenetic analyses of the resulting data, combined with those from previously published Siberian arctic and sub-arctic populations, revealed that remnants of the ancient Siberian gene pool are still evident in Siberian populations, suggesting that the founding haplotypes of the Native American A-D branches originated in different parts of Siberia. Thus, lineage A complete sequences revealed in the Mansi of the Lower Ob and the Ket of the Lower Yenisei belong to A1, suggesting that A1 mtDNAs occasionally found in the remnants of hunting-gathering populations of northwestern and northern Siberia belonged to a common gene pool of the Siberian progenitors of Paleoindians. Moreover, lineage B1, which is the most closely related to the American B2, occurred in the Tubalar and Tuvan inhabiting the territory between the upper reaches of the Ob River in the west, to the Upper Yenisei region in the east. Finally, the sequence variants of haplogroups C and D, which are most similar to Native American C1 and D1, were detected in the Ulchi of the Lower Amur. Overall, our data suggest that the immediate ancestors of the Siberian/Beringian migrants who gave rise to ancient (pre-Clovis) Paleoindians have a common origin with aboriginal people of the area now designated the Altai-Sayan Upland, as well as the Lower Amur/Sea of Okhotsk region.

DNA, Mitochondrial↗
PubMed2001

[Epidemiology of stroke in Siberia].

Based on WHO MONICA methods and diagnostic criteria, it is shown that first-ever stroke incidence and mortality in Siberia (a total number of residents included in the analysis varied from 450,000 to about 800,000) that are among the highest in the world. In Novosibirsk, for the period from 1982 through 1991 there was a trend towards decreasing stroke incidence and mortality rates, but for the period from 1992 through 1997 there was a trend towards increasing there rates in both men and women. Age-standardized (US white population was used as a standard) stroke incidence rates increased from west to east and from south to north across Siberia, with a corresponding increase in the proportion of hemorrhagic strokes. In 1987-1988, age-adjusted stroke incidence rate in Novosibirsk was 212 per 100,000 residents per year, in Krasnoyarsk--325, in Tynda--329, in Anadyr--348. Stroke-case fatality rates ranged from 28% in Tynda to 41% in Anadyr. A multivariate regression analysis revealed that hypertension, left ventricular hypertrophy, ischemic heart disease. mitral valve disease, current cigarette smoking, excessing body mass index, winter season, and low ambient temperature are all significant and independent risk factors for the occurrence of ischemic stroke in Novosibirsk. A significant association between stroke occurrence and air pressure/geomagnetic activity change was found. Possible reasons for such unfavorable trends in stroke incidence in Siberia are discussed, and an optimal approach for improving organization of cerebrovascular disease care is suggested.

Aged↗
PubMed2001

[Features of the association of Helicobacter pylori infection and ulcer in Europeans and Mongoloids in Siberia].

AIM: To study association between Helicobacter Pylori infection in ulcer in native population and migrants in Siberia. MATERIALS AND METHODS: Epidemiological survey of ulcer has been performed in Northern (Evenkia, Yakutia) and Southern (Khakasia) regions of Siberia. Clinical examination covered 3908 Europeoids (Russians, Ukrainians) and 1999 Mongoloids (Evenks, Evens, Khakases). Endoscopic examination was made in 2144 patients. Light microscopy has detected Helicobacter pylori (HP) in 453 patients (215 migrants and 238 natives). RESULTS: Prevalence of ulcer in the South of Siberia was 6.1 and 1.5% for migrants and natives, respectively. In the North--8.9 and 0.6%, respectively. HP was diagnosed in 83.7% of Mongoloids and 69.2% of Europeoids in the South and 92.2 and 100%, respectively, in the North. HP index, contamination and adhesion in migrants were higher than in native population. CONCLUSION: Siberial Europeoids and Mongoloids have specific ethnic features of ulcer occurrence and its association with HP. Native population is protected better from the pathogenic bacteria. Further study of the causes of virulent bacterial properties and mechanisms maintaining long persistance of HP in the stomach is necessary.

Asian People↗