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1.
Sci Total Environ ; 922: 171284, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38432389

RESUMO

Humic thermokarst lakes of permafrost peatlands in Western Siberia Lowland (WSL) are major environmental controllers of carbon and nutrient storage in inland waters and greenhouse gases emissions to the atmosphere in the subarctic. In contrast to sizable former research devoted to hydrochemical and hydrobiological (phytoplankton) composition, zooplankton communities of these thermokarst lakes and thaw ponds remain poorly understood, especially along the latitudinal gradient, which is a perfect predictor of permafrost zones. To fill this gap, 69 thermokarst lakes of the WSL were sampled using unprecedented spatial coverage, from continuous to sporadic permafrost zone, in order to assess zooplankton (Cladocera, Copepoda, Rotifera) diversity and abundance across three main open water physiological seasons (spring, summer and autumn). We aimed at assessing the relationship of environmental factors (water column hydrochemistry, nutrients, and phytoplankton parameters) with the abundance and diversity of zooplankton. A total of 74 zooplankton species and taxa were detected, with an average eight taxa per lake/pond. Species richness increased towards the north and reached the maximum in the continuous permafrost zone with 13 species found in this zone only. In contrast, the number of species per waterbody decreased towards the north, which was mainly associated with a decrease in the number of cladocerans. Abundance and diversity of specific zooplankton groups strongly varied across the seasons and permafrost zones. Among the main environmental controllers, Redundancy Analysis revealed that water temperature, lake area, depth, pH, Dissolved Inorganic and Organic Carbon and CO2 concentrations were closely related to zooplankton abundance. Cladocerans were positively related to water temperature during all seasons. Copepods were positively related to depth and lake water pH in all seasons. Rotifers were related to different factors in each season, but were most strongly associated with DOC, depth, CH4, phytoplankton and cladoceran abundance. Under climate warming scenario, considering water temperature increase and permafrost boundary shift northward, one can expect an increase in the diversity and abundance of cladocerans towards the north which can lead to partial disappearance of copepods, especially rare calanoid species.


Assuntos
Cladóceros , Copépodes , Pergelissolo , Rotíferos , Animais , Estações do Ano , Sibéria , Zooplâncton/fisiologia , Lagos/química , Rotíferos/fisiologia , Fitoplâncton/fisiologia , Copépodes/fisiologia , Carbono , Água
2.
Genome Biol Evol ; 16(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38526010

RESUMO

Human populations across a vast area in northern Eurasia, from Fennoscandia to Chukotka, share a distinct genetic component often referred to as the Siberian ancestry. Most enriched in present-day Samoyedic-speaking populations such as Nganasans, its origins and history still remain elusive despite the growing list of ancient and present-day genomes from Siberia. Here, we reanalyze published ancient and present-day Siberian genomes focusing on the Baikal and Yakutia, resolving key questions regarding their genetic history. First, we show a long-term presence of a unique genetic profile in southern Siberia, up to 6,000 yr ago, which distinctly shares a deep ancestral connection with Native Americans. Second, we provide plausible historical models tracing genetic changes in West Baikal and Yakutia in fine resolution. Third, the Middle Neolithic individual from Yakutia, belonging to the Belkachi culture, serves as the best source so far available for the spread of the Siberian ancestry into Fennoscandia and Greenland. These findings shed light on the genetic legacy of the Siberian ancestry and provide insights into the complex interplay between different populations in northern Eurasia throughout history.


Assuntos
Genética Populacional , Genoma Humano , População da Ásia Setentrional , Humanos , Sibéria
3.
Ticks Tick Borne Dis ; 15(3): 102327, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460341

RESUMO

The bites of hard ticks are the major route of transmission of tick-borne infections to humans, causing thousands of cases of diseases worldwide. However, the characteristics of the human population that is exposed to tick bites are still understudied. This work is aimed at characterizing both the structure of the population directly contacting ticks and the human behavioral features associated with tick bites. We studied 25,970 individuals who sought medical help after a tick bite at the Centre for Diagnostics and Prevention of Tick-borne Infections (CDPTBI) in Irkutsk City (Russian Federation). The demographic and behavioral characteristics of the human population were analyzed using z-tests for proportions, the Mann-Whitney U test, and the Spearman rank correlation coefficient. The majority of bitten people were urban residents (70 %), and most of them were either of active ages between 30 and 74 years old (62 %), or children between 0 and 9 years old (approximately 20%). Tick bites occurred mostly in the range of 150 km around the location of the diagnostic facility (83 %). In comparison to the general population, significant differences were revealed in the representation of different age groups among bitten people. The population affected by tick bites included fewer men and women in the ages of 10-29 and over 75 years old than would be predicted based on the demographics of the general population. Vice versa, the proportions of people in the ages of 5-9 and 60-74 increased among bitten people. Among men, such activities (in order of occurrence) as "leisure and recreation", "visiting allotments", "foraging for forest food", and "fulfilling work duties" tend to be more associated with tick bites. Among women, tick bites occurred mainly during "visiting allotments", "leisure and recreation", "visiting cemeteries" and "contact with pets and plants at home". The overall vaccination rate was 12 %; however, significantly more men than women were vaccinated against tick-borne encephalitis (up to 20 % vs. approximately 7 % respectively). The structure of the tick bite - affected population suggests that it is age-specific human behavior that mainly determines the frequency of contact between people and ticks. However, in several age groups, especially among children from 5 to 9 and people aged 30-39 years old, gender-related factors could significantly change the exposure of people to tick bites.


Assuntos
Ixodidae , Picadas de Carrapatos , Doenças Transmitidas por Carrapatos , Carrapatos , Masculino , Animais , Criança , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Recém-Nascido , Lactente , Pré-Escolar , Picadas de Carrapatos/epidemiologia , Sibéria/epidemiologia , Federação Russa , Doenças Transmitidas por Carrapatos/epidemiologia
4.
Zootaxa ; 5406(2): 288-296, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480152

RESUMO

The new species Euphanias sergreevae sp. nov. from the shores of a saline lake in Western Siberia, Russia is described in this paper. The paper examines the type material of two closely related species Euphanias pusanovi Blinstein, 1976 and Euphanias pliginskii Bernhauer, 1912. The species are illustrated with color photographs of the habitus and aedeagus, scanning electron micrographs, and line drawings of the terminalia. A complete distribution map for all members of the genus is given and distribution patterns are discussed.


Assuntos
Besouros , Animais , Sibéria , Distribuição Animal , Estruturas Animais , Tamanho do Órgão , Federação Russa
5.
Int J Med Mushrooms ; 26(1): 45-53, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38305261

RESUMO

The antiviral activity of aqueous and ethanol extracts from the fruiting bodies of gasteroid Basidiomy-cetes of Western Siberia: Lycoperdon pyriforme, Lycoperdon perlatum, and Phallus impudicus, as well as an aqueous extract from cultivated mycelium of P. impudicus and total polysaccharides from it, on MDCK cell culture against influenza A virus, was studied. Aqueous and ethanol extracts from the fruiting bodies of all studied gasteroid fungi showed antiviral activity against human influenza virus A/Aichi/2/68 (H3N2) and bird A/chicken/Kurgan/05/2005 virus (H5N1). At the same time, extracts from P. impudicus and L. pyriforme showed more pronouncing antiviral activity compared to the activity of the reference drug Tamiflu against the A/H5N1 avian influenza virus. A high antiviral efficacy of an aqueous extract from cultivated mycelium of the P. impudicus and a sample of total polysaccharides from this extract against the A/H5N1 avian influenza virus was revealed.


Assuntos
Agaricales , Virus da Influenza A Subtipo H5N1 , Animais , Humanos , Antivirais/farmacologia , Sibéria , Vírus da Influenza A Subtipo H3N2 , Etanol , Polissacarídeos/farmacologia
6.
Funct Integr Genomics ; 24(2): 42, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396290

RESUMO

Four species of Saussurea, namely S. involucrata, S. orgaadayi, S. bogedaensis, and S. dorogostaiskii, are known as the "snow lotus," which are used as traditional medicines in China (Xinjiang), Kyrgyzstan, Mongolia, and Russia (Southern Siberia). These species are threatened globally, because of illegal harvesting and climate change. Furthermore, the taxonomic classification and identification of these threatened species remain unclear owing to limited research. The misidentification of medicinal species can sometimes be harmful to health. Therefore, the phylogenetic and genomic features of these species need to be confirmed. In this study, we sequenced five complete chloroplast genomes and seven nuclear ITS regions of four snow lotus species and other Saussurea species. We further explored their genetic variety, selective pressure at the sequence level, and phylogenetic relationships using the chloroplast genome, nuclear partial DNA sequences, and morphological features. Plastome of the snow lotus species has a conserved structure and gene content similar to most Saussurea species. Two intergenic regions (ndhJ-ndhK and ndhD-psaC) show significantly high diversity among chloroplast regions. Thus, ITS and these markers are suitable for identifying snow lotus species. In addition, we characterized 43 simple sequence repeats that may be useful in future population genetic studies. Analysis of the selection signatures identified three genes (rpoA, ndhB, and ycf2) that underwent positive selection. These genes may play important roles in the adaptation of the snow lotus species to alpine environments. S. dorogostaiskii is close to S. baicalensis and exhibits slightly different adaptation from others. The taxonomic position of the snow lotus species, confirmed by morphological and molecular evidence, is as follows: (i) S. involucrata has been excluded from the Mongolian flora due to misidentification as S. orgaadayi or S. bogedaensis for a long time; (ii) S. dorogostaiskii belongs to section Pycnocephala subgenus Saussurea, whereas other the snow lotus species belong to section Amphilaena subgenus Amphilaena; and (iii) S. krasnoborovii is synonymous of S. dorogostaiskii. This study clarified the speciation and lineage diversification of the snow lotus species in Central Asia and Southern Siberia.


Assuntos
Asteraceae , Lotus , Saussurea , Saussurea/genética , Saussurea/química , Filogenia , Sibéria
7.
Genes (Basel) ; 15(1)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38254975

RESUMO

The Kazakhstan-Siberia Network for Spring Wheat Improvement (KASIB) was established in 2000, forming a collaboration between breeding and research programs through biannual yield trials. A core set of 142 genotypes from 15 breeding programs was selected, genotyped for 81 DNA functional markers and phenotyped for 10 agronomic traits at three sites in Kazakhstan (Karabalyk, Shortandy and Shagalaly) and one site in Russia (Omsk) in 2020-2022. The study aim was to identify markers demonstrating significant effects on agronomic traits. The average grain yield of individual trials varied from 118 to 569 g/m2. Grain yield was positively associated with the number of days to heading, plant height, number of grains per spike and 1000-kernel weight. Eight DNA markers demonstrated significant effects. The spring-type allele of the Vrn-A1 gene accelerated heading by two days (5.6%) and was present in 80% of the germplasm. The winter allele of the Vrn-A1 gene significantly increased grain yield by 2.7%. The late allele of the earliness marker per se, TaMOT1-D1, delayed development by 1.9% and increased yield by 4.5%. Translocation of 1B.1R was present in 21.8% of the material, which resulted in a 6.2% yield advantage compared to 1B.1B germplasm and a reduction in stem rust severity from 27.6 to 6.6%. The favorable allele of TaGS-D1 increased both kernel weight and yield by 2-3%. Four markers identified in ICARDA germplasm, ISBW2-GY (Kukri_c3243_1065, 3B), ISBW3-BM (TA004946-0577, 1B), ISBW10-SM2 (BS00076246_51, 5A), ISBW11-GY (wsnp_Ex_c12812_20324622, 4A), showed an improved yield in this study of 3-4%. The study recommends simultaneous validation and use of selected markers in KASIB's network.


Assuntos
Melhoramento Vegetal , Triticum , Triticum/genética , Sibéria , Cazaquistão , Fenótipo , Biomarcadores , Grão Comestível
8.
J Environ Radioact ; 273: 107387, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295587

RESUMO

The Laptev Sea is remote from the impact of technogenic radionuclides, which makes it a convenient natural testing ground for determining the natural flux of radionuclides to the marine environment and further to sediments. Analysis of the use of different models for dating recent sediments using 210Pb showed that in conditions of erosion-accumulative (unstable) sedimentation of the shelf, the constant initial concentration (CIC) model is most preferable. This study uses a new age-depth model "RUS2023" to recalculate the excess 210Pb (210Pbex) activity into calendar years, which is a variation of the CIC model. The proposed model differs in that when calculating the age of horizons, corrections for the grain-size composition and sorption capacity of sediments are used. In ten studied sediment cores from the Laptev Sea, using this model, strong variability in 210Pbex flux from the atmosphere was revealed. One of the possible sources of 210Pbex, in addition to global fallout due to the decay of 222Rn, are forest fires, which contribute to its burst emission into the atmosphere as part of aerosols. Taking into account the area of forest fires in Siberia, Yakutia and the Far East, they are able to supply into the atmosphere together about 2.5 × 1014 Bq year-1, which is comparable to emissions from all nuclear power plants in Russia. This model can also be useful in reconstructing sedimentological events that cause disturbances in the chronology of sedimentary sequence, for example, when dating landslides or turbidites.


Assuntos
Monitoramento de Radiação , Radioisótopos de Césio/análise , Chumbo/análise , Sedimentos Geológicos , Sibéria
9.
Clin Epigenetics ; 15(1): 189, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38053163

RESUMO

BACKGROUND: Yakuts are one of the indigenous populations of the subarctic and arctic territories of Siberia characterized by a continental subarctic climate with severe winters, with the regular January average temperature in the regional capital city of Yakutsk dipping below - 40 °C. The epigenetic mechanisms of adaptation to such ecologies and environments and, in particular, epigenetic age acceleration in the local population have not been studied before. RESULTS: This work reports the first epigenetic study of the Yakutian population using whole-blood DNA methylation data, supplemented with the comparison to the residents of Central Russia. Gene set enrichment analysis revealed, among others, geographic region-specific differentially methylated regions associated with adaptation to climatic conditions (water consumption, digestive system regulation), aging processes (actin filament activity, cell fate), and both of them (channel activity, regulation of steroid and corticosteroid hormone secretion). Further, it is demonstrated that the epigenetic age acceleration of the Yakutian representatives is significantly higher than that of Central Russia counterparts. For both geographic regions, we showed that epigenetically males age faster than females, whereas no significant sex differences were found between the regions. CONCLUSIONS: We performed the first study of the epigenetic data of the Yakutia cohort, paying special attention to region-specific features, aging processes, age acceleration, and sex specificity.


Assuntos
Metilação de DNA , Epigênese Genética , Humanos , Masculino , Feminino , Sibéria , Regiões Árticas
10.
Probl Sotsialnoi Gig Zdravookhranenniiai Istor Med ; 31(Special Issue 2): 1282-1289, 2023 Oct.
Artigo em Russo | MEDLINE | ID: mdl-38069899

RESUMO

Annotation. The review article is devoted to the healthcare system of Iceland, which demonstrates some of the best indicators of public health in the world at relatively low costs for a developed European country. The successful experience of Icelandic healthcare is important for Russia, on the one hand, due to the proximity of this country to many Russian regions in terms of climatic and geographical location, demography and territorial development. On the other hand, the success of Iceland's healthcare is closely linked to the development of a model, in many ways similar to the Soviet model of Nikolai Semashko, which Russia has abandoned. The authors believe that Iceland's experience can be used in the modernization of regional healthcare systems in Eastern Siberia, the Far East and the Arctic, as well as Russian healthcare in general.


Assuntos
Atenção à Saúde , Islândia , Federação Russa , Sibéria , U.R.S.S.
11.
Probl Sotsialnoi Gig Zdravookhranenniiai Istor Med ; 31(Special Issue 2): 1290-1296, 2023 Oct.
Artigo em Russo | MEDLINE | ID: mdl-38069900

RESUMO

Annotation. The review article is devoted to the healthcare system of Iceland, which demonstrates some of the best indicators of public health in the world at relatively low costs for a developed European country. The successful experience of Icelandic healthcare is important for Russia, on the one hand, due to the proximity of this country to many Russian regions in terms of climatic and geographical location, demography and territorial development. On the other hand, the success of Iceland's healthcare is closely linked to the development of a model, in many ways similar to the Soviet model of Nikolai Semashko, which Russia has abandoned. The authors believe that Iceland's experience can be used in the modernization of regional healthcare systems in Eastern Siberia, the Far East and the Arctic, as well as Russian healthcare in general.


Assuntos
Atenção à Saúde , Islândia , Federação Russa , Sibéria , U.R.S.S.
12.
Ter Arkh ; 95(11): 1009-1012, 2023 Dec 22.
Artigo em Russo | MEDLINE | ID: mdl-38158961

RESUMO

The relationship between government and university medicine in the context of the development of the Asian "colonial" periphery of Russia in the late imperial period are studied. It is concluded that these relationship, the manifestations of which were most pronounced in the period of the fight against epidemics, are not quite standard from the point of view of model of the classical relationship between power and knowledge in the colonial context of European maritime empires. This is connected mainly with the social portrait of the university intelligentsia, with the peculiarities of their professional socialization, which led to the fact that in Siberia they broadcast the experience of the European metropolises, rather than the colonies.


Assuntos
Epidemias , Governo , Humanos , Sibéria/epidemiologia , Universidades , Federação Russa/epidemiologia
13.
J Hum Evol ; 185: 103453, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37931353

RESUMO

The Initial Upper Paleolithic (IUP) is one of the most important phases in the recent period of the evolution of humans. During a narrow period in the first half of Marine Isotope Stage 3 laminar industries, accompanied by developed symbolism and specific blade technology, emerged over a vast area, replacing different variants of the Middle Paleolithic. In western Eurasia, the earliest appearance of IUP technology is seen at the Boker Tachtit site, dated ca. 50 ka cal BP. The earliest evidence of IUP industries in the Balkans and Central Europe, linked to the spread of Homo sapiens, has been dated to around 48 ka cal BP. A key area of IUP dispersals are the mountains and piedmont of southern Siberia and eastern Central Asia. One of the reference assemblages here is Kara-Bom, an open-air site in the Siberian Altai. Three major settlement phases are distinguished in the sediment sequence. In this paper, we present the results of new radiocarbon determinations and Bayesian models. We find that the latest phase of the IUP, Upper Paleolithic 1 ('UP1') is bracketed between 43 and 35 ka cal BP (at 95.4% probability). The earliest IUP phase, 'UP2', begins to accumulate from ca. 49 ka cal BP and ends by ca. 45 ka cal BP. The Middle Paleolithic 'MP2' assemblages all fall prior to 50 ka cal BP. We can detect a spatial distribution of dates from the geographic core of the IUP beyond the Altai where it appears around 47-45 ka cal BP. The current distribution of dates suggests a west-east dispersal of the IUP technocomplex along the mountain belts of Central Asia and South Siberia.


Assuntos
Hominidae , Humanos , Animais , Teorema de Bayes , Península Balcânica , Sibéria , Tecnologia , Arqueologia , Fósseis
14.
Nature ; 623(7987): 550-554, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914937

RESUMO

The origin of vertebrate paired appendages is one of the most investigated and debated examples of evolutionary novelty1-7. Paired appendages are widely considered as key innovations that enabled new opportunities for controlled swimming and gill ventilation and were prerequisites for the eventual transition from water to land. The past 150 years of debate8-10 has been shaped by two contentious theories4,5: the ventrolateral fin-fold hypothesis9,10 and the archipterygium hypothesis8. The latter proposes that fins and girdles evolved from an ancestral gill arch. Although studies in animal development have revived interest in this idea11-13, it is apparently unsupported by fossil evidence. Here we present palaeontological support for a pharyngeal basis for the vertebrate shoulder girdle. We use computed tomography scanning to reveal details of the braincase of Kolymaspis sibirica14, an Early Devonian placoderm fish from Siberia, that suggests a pharyngeal component of the shoulder. We combine these findings with refreshed comparative anatomy of placoderms and jawless outgroups to place the origin of the shoulder girdle on the sixth branchial arch. These findings provide a novel framework for understanding the origin of the pectoral girdle. Our evidence clarifies the location of the presumptive head-trunk interface in jawless fishes and explains the constraint on branchial arch number in gnathostomes15. The results revive a key aspect of the archipterygium hypothesis and help reconcile it with the ventrolateral fin-fold model.


Assuntos
Nadadeiras de Animais , Evolução Biológica , Peixes , Fósseis , Vertebrados , Animais , Nadadeiras de Animais/anatomia & histologia , Peixes/anatomia & histologia , Paleontologia , Tomografia Computadorizada por Raios X , Vertebrados/anatomia & histologia , Sibéria
15.
Science ; 382(6674): 982-983, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38033060

RESUMO

8000 years ago-long before farming arrived-people in Siberia built defensive structures.


Assuntos
Caça , Humanos , Fazendas/história , Sibéria , Caça/história
16.
Tuberculosis (Edinb) ; 143S: 102368, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38012918

RESUMO

In this study, we tested the skeletal human remains from the 18th - early 19th century Orthodox cemeteries in Irkutsk, Eastern Siberia, for tuberculosis-associated morphological alterations and Mycobacterium tuberculosis DNA. The morphologically studied bone collection included 591 individuals of mainly Caucasian origin. The molecular methods (IS6110-PCR and spoligotyping) suggested that at least four individuals (out of 15 TB-suspected, DNA-tested) were positive for the presence of M. tuberculosis DNA. All of them were males (3 maturus, 1 maturus senilis). Two of them date back to the second and third quarters of the 18th century, another to the last quarter of the 18th century, and the last one to the second half of the 19th century. The combined molecular analysis cautiously suggested presence of different strains and at least some of them represented not the currently predominant in Siberia Beijing genotype (M. tuberculosis East-Asian lineage) but strains of European origin. In conclusion, this study presented bioarchaeological and molecular evidence of tuberculosis in human skeletal remains from 18th-19th century Orthodox cemeteries in Irkutsk, Eastern Siberia. The samples are not M. bovis and represent human M. tuberculosis sensu stricto. Their precise phylogenetic identity is elusive but evokes the European/Russian origin of at least some isolates.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Masculino , Humanos , Feminino , Mycobacterium tuberculosis/genética , Sibéria , Restos Mortais , Filogenia , Cemitérios , Tuberculose/microbiologia , Genótipo , DNA
17.
Viruses ; 15(10)2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37896792

RESUMO

The comparison of the development of the SARS-CoV-2 epidemic in several neighboring regions can help researchers to assess the risks and develop more effective strategies and approaches in the field of preventive medicine. We analyzed the infection and mortality statistics for the 2020-2022 period in ten individual regions of the Siberian Federal District of Russia. We also sequenced complete genomes, which allowed us to analyze the genetic diversity of SARS-CoV-2 circulated in each of the ten regions and to build a phylogenetic dendrogram for the virus variants. The ParSeq v.1.0 software was developed to automate and speed up the processing and analysis of viral genomes. At the beginning of the pandemic, in the first two waves, the B.1.1 variant (20B) dominated in all regions of the Siberian Federal District. The third and fourth waves were caused by the Delta variant. Mortality during this period was at a maximum; the incidence was quite high, but the number of deposited genomes with GISAID during this period was extremely low. The maximum incidence was at the beginning of 2022, which corresponds to the arrival of the Omicron variant in the region. The BA.5.2 variant became the dominant one. In addition, by using NextClade, we identified three recombinants in the most densely populated areas.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Sibéria/epidemiologia , SARS-CoV-2/genética , Filogenia , COVID-19/epidemiologia , Pandemias
18.
Mol Biol (Mosk) ; 57(5): 792-796, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37752644

RESUMO

Nucleotide sequence variability of whole mitochondrial genomes (mtDNA) was analyzed and mutation spectra were reconstructed (by L-chain of mtDNA) in four regional groups of indigenous populations representing Northeastern and Southern Siberia, Western Asia, and the Americas. The pyrimidine transitions were found to be predominant in all groups; of these, the T→C substitutions were most frequent. The second most common in all regional groups (except Northeastern Siberia) are A→G substitutions. Of the transversions, in all the populations studied the C→A substitutions dominate. Between-regional differences in the distribution of nucleotide substitutions in mtDNA mutation spectra were not detected. However, a significant (4-fold) decrease in the number of mutations in mitochondrial gene pools was detected in the indigenous population of Northeastern Siberia compared to other regions. This may be due to the increased effect of negative selection on mtDNA in the Far North environment, which prevents the accumulation of new mutations, and genetic drift, which is most pronounced in isolated and small populations of Northeastern Siberia. Because of the lack of between-regional differences in mtDNA mutation spectra, the results we obtained do not allow us to confirm the hypothesis that the T→C substitution frequency is a molecular marker of the level of oxidative stress in mitochondria (at least for germline mutations).


Assuntos
Genoma Mitocondrial , Humanos , Genoma Mitocondrial/genética , Mutação , DNA Mitocondrial/genética , Mitocôndrias/genética , Sibéria
19.
Viruses ; 15(9)2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37766302

RESUMO

The metagenomic analysis of mosquitoes allows for the genetic characterization of mosquito-associated viruses in different regions of the world. This study applied a metagenomic approach to identify novel viral sequences in seven species of mosquitoes collected from the Novosibirsk region of western Siberia. Using NGS sequencing, we identified 15 coding-complete viral polyproteins (genomes) and 15 viral-like partial sequences in mosquitoes. The complete sequences for novel viruses or the partial sequences of capsid proteins, hypothetical viral proteins, and RdRps were used to identify their taxonomy. The novel viral sequences were classified within the orders Tymovirales and Picornavirales and the families Partitiviridae, Totiviridae, Tombusviridae, Iflaviridae, Nodaviridae, Permutotetraviridae, and Solemoviridae, with several attributed to four unclassified RNA viruses. Interestingly, the novel putative viruses and viral sequences were mainly associated with the mosquito Coquillettidia richardii. This study aimed to increase our understanding of the viral diversity in mosquitoes found in the natural habitats of Siberia, which is characterized by very long, snowy, and cold winters.


Assuntos
Culicidae , Nodaviridae , Humanos , Animais , Viroma , Sibéria , Proteínas do Capsídeo/genética
20.
Sci Adv ; 9(38): eadi0189, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37738346

RESUMO

The dispersal of Homo sapiens in Siberia and Mongolia occurred by 45 to 40 thousand years (ka) ago; however, the climatic and environmental context of this event remains poorly understood. We reconstruct a detailed vegetation history for the Last Glacial period based on pollen spectra from Lake Baikal. While herb and shrub taxa including Artemisia and Alnus dominated throughout most of this period, coniferous forests rapidly expanded during Dansgaard-Oeschger (D-O) events 14 (55 ka ago) and 12 to 10 (48 to 41 ka ago), with the latter presenting the strongest signal for coniferous forest expansion and Picea trees, indicating remarkably humid conditions. These abrupt forestation events are consistent with obliquity maxima, so that we interpret last glacial vegetation changes in southern Siberia as being driven by obliquity change. Likewise, we posit that major climate amelioration and pronounced forestation precipitated H. sapiens dispersal into Baikal Siberia 45 ka ago, as chronicled by the appearance of the Initial Upper Paleolithic.


Assuntos
Florestas , Lagos , Humanos , Sibéria , Pólen , Árvores
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