Changes in the vascular flora of Khatanga village and its surrounding area, Taimyrsky Biosphere Reserve, over a long period

The results of the floristic survey of Khatanga surroundings are given. A comparison of the flora's current state with the earlier changes in 1905–1955 and with data of regional floras is conducted. There are 58 species listed in these references, which we have not detected. We believe that they have disappeared from the flora, or there was confusion in determination of plant specimens, or there were errors in the geographical locations. We found 93 species, not mentioned in the cited sources. The total list includes currently 359 species of vascular plants. Changes in the flora are caused by natural processes (change of climate, the hydrological regime of rivers, etc.) аs well as by human transformation of the landscape. An analysis of the flora is conducted, on the basis of which we regard it as belonging to the Asian hypoarctoboreal subtype of the Hypoarctic type

Climate change in Eastern Taimyr over the last 80 years and the warming impact on biodiversity and ecosystem processes in its territory

The analysis of long-term changes of mean annual temperatures and the active temperature sum over 80 years was carried out using data of the Khatanga meteorological station. Since the 1990s, an essential warming was observed, especially after 2000. The warming influence on vegetation takes place immediately (the ecosystem composition changes due to the degradation of cryogenic processes) as well as directly by increasing the time of the vegetation period and the total amount of heat on plants. As a result, in the last few years, the lead of phenological phenomena terms is observed – the time of foliage expansion and efflorescence of plants-indicators, geese arriving, mosquitos appearance, ice thawing. By long term monitoring data, the moving of some north-taiga plant species to forest tundra and tundra is observed, as well as their establishing in vegetation communities. However, at this moment, the character of the vegetation is stable. The occurrence of taiga animals is increased in tundra and forest tundra. An active revival of larch is observed in forest tundra and north sparse forests. A removing forest border to the north is not observed, but in the southern mountains of Taimyr its replacing on higher levels could be seen. A decreasing summer precipitation quantity increases the possibility of forest fires, spring and bog drying. It influences negatively on bog flora and near-water fauna. It is possible, that the main reason of the local climate change at the East of Taimyr is less connected to the global planet change, but much more to pulsations of the strong Siberian anticyclone

Clinical aspects of TP53 gene inactivation in diffuse large B-cell lymphoma

Abstract Background The knowledge about specific mechanisms generating TP53 dysfunction in diffuse large B-cell lymphoma is limited. The aim of the current study was to comprehensively explore TP53 gene variability resulting from somatic mutations, promoter methylation, and allelic imbalance in tumorous tissue of diffuse large B-cell lymphoma (DLBCL). Methods DNA samples from 74 patients with DLBCL were used. Genomic DNA was isolated from paraffin blocks of lymph nodes or from extranodal biopsies of tumors by the phenol–chloroform extraction method with guanidine. Analysis of coding sequences of the TP53 gene was based on Sanger’s direct sequencing method. The methylation status of the TP53 promoter was analyzed using by methylation-specific PCR on bisulfite-converted DNA. Assessment of the detected mutations was carried out in the IARC TP53 Database and the TP53 UMD mutation database of human cancer. Results The mutations in regions coding for the DNA-binding domain were prevalent (95%). In the analyzed sample of patients, codons 275, 155, 272, and 212 were hotspots of mutations in the TP53 gene. In addition, functionally significant intron mutations (IVS6-36G > C and IVS5 + 43G > T) were detected. Instances of TP53 promoter methylation were observed only in a few samples of diffuse large B-cell lymphoma tissue. Furthermore, loss of heterozygosity was revealed only in the subgroup of patients with altered status of the gene (mutations were detected in five patients and promoter methylation in one case). Conclusions Thus, the results suggest that there are two sequential events in the formation of diffuse large B-cell lymphoma in at least some cases. The first event is mutation or methylation of the TP53 promoter, leading to appearance of a cell with increased risk of malignant transformation. The second event is the loss of an intact allele of the gene; this change is necessary for tumorigenesis. We identified TP53 mutation patterns in a Russian cohort of patients with de novo DLBCL who were treated with R-CHOP and R-CHOP-like regimens and confirmed that TP53 mutation status is a valuable prognostic biomarker

The Methylation of the p53 Targets the Genes MIR-203, MIR-129-2, MIR-34A and MIR-34B/C in the Tumor Tissue of Diffuse Large B-Cell Lymphoma

The regulation of oncogenes by microRNA is a focus of medical research. hsa-miR-203, hsa-mir-129, hsa-miR-34a, hsa-miR-34b and hsa-miR-34c are oncosuppressive microRNAs that mediate the antitumor activity of p53. We seek to evaluate the frequencies, co-occurrence and clinical significance of the methylation of the MIR-203, MIR-129-2, MIR-34A and MIR-34B/C genes in the tumor tissue of diffuse large B-cell lymphoma (DLBCL). The methylation was assessed in 73 samples of DLBCL and in 11 samples of lymph nodes of reactive follicular hyperplasia by Methyl-Specific Polymerase Chain Reaction (MS-PCR) and Methylation-Sensitive High-Resolution-Melting (MS-HRM) methods. All four studied genes were not methylated in the tissue of reactive lymphatic nodes. The methylation frequencies of the MIR-129-2, MIR-203, MIR-34A and MIR-34B/C genes in lymphoma tissue were 67%, 66%, 27% and 62%, respectively. Co-occurrence of MIR-203, MIR-129-2 and MIR-34B/C genes methylation, as well as the methylation of MIR-34B/C and MIR-34A pair genes were detected. The MIR-34A gene methylation was associated with increased International Prognostic Index (IPI) (p = 0.002), whereas the MIR-34B/C (p = 0.026) and MIR-203 (p = 0.011) genes’ methylation was connected with Ki-67 expression level in tumor tissue at more than 45%. We found an increasing frequency of detection of MIR-34A gene methylation in the group of patients with the Germinal-Center B-cell like (GCB-like) subtype of DLBCL (p = 0.046). There was a trend towards a decrease in the remission frequency after the first line of therapy (p = 0.060) and deterioration in overall survival (OS) (p = 0.162) in patients with DLBCL with methylation of the MIR-34A promoter. The methylation of the MIR-34A, MIR-34B/C, MIR-129-2 and MIR-203 genes in DLBCL is tumor-specific and occurs in combination. The methylation of the studied genes may be a potential differential diagnostic biomarker to distinguish between lymphoma and reactive lymph nodes, while its independent predictive value has not been confirmed yet

A raster version of the Circumpolar Arctic Vegetation Map (CAVM)

Land cover maps are the basic data layer required for understanding and modeling ecological patterns and processes. The Circumpolar Arctic Vegetation Map (CAVM), produced in 2003, has been widely used as a base map for studies in the arctic tundra biome. However, the relatively coarse resolution and vector format of the map were not compatible with many other data sets. We present a new version of the CAVM, building on the strengths of the original map, while providing a finer spatial resolution, raster format, and improved mapping. The Raster CAVM uses the legend, extent and projection of the original CAVM. The legend has 16 vegetation types, glacier, saline water, freshwater, and non-arctic land. The Raster CAVM divides the original rock-water-vegetation complex map unit that mapped the Canadian Shield into two map units, distinguishing between areas with lichen- and shrub-dominated vegetation. In contrast to the original hand-drawn CAVM, the new map is based on unsupervised classifications of seventeen geographic/floristic sub-sections of the Arctic, using AVHRR and MODIS data (reflectance and NDVI) and elevation data. The units resulting from the classification were modeled to the CAVM types using a wide variety of ancillary data. The map was reviewed by experts familiar with their particular region, including many of the original authors of the CAVM from Canada, Greenland (Denmark), Iceland, Norway (including Svalbard), Russia, and the U.S. The analysis presented here summarizes the area, geographical distribution, elevation, summer temperatures, and NDVI of the map units. The greater spatial resolution of the Raster CAVM allowed more detailed mapping of water-bodies and mountainous areas. It portrays coastal-inland gradients, and better reflects the heterogeneity of vegetation type distribution than the original CAVM. Accuracy assessment of random 1-km pixels interpreted from 6 Landsat scenes showed an average of 70% accuracy, up from 39% for the original CAVM. The distribution of shrub-dominated types changed the most, with more prostrate shrub tundra mapped in mountainous areas, and less low shrub tundra in lowland areas. This improved mapping is important for quantifying existing and potential changes to land cover, a key environmental indicator for modeling and monitoring ecosystems. The final product is publicly available at www.geobotany.uaf.edu and at Mendeley Data, DOI: 10.17632/c4xj5rv6kv.1

Contribution to the flora of Asian and European countries: new national and regional vascular plant records, 7

The paper presents new records for 29 vascular plant species from 12 Eurasian countries. Seven taxa (Agave sisalana, Austrocylindropuntia subulata, Lagurus ovatus subsp. nanus, Opuntia stricta, Orobanche serbica, Oxalis articulata, Vitis Ã instabilis) are reported from Albania, one (Allium carinatum) from the Europaean part of Russia, six (Dipsacus fullonum, Gagea shmakoviana, Mentha Ã dalmatica, Thymus indigirkensis, Thymus sergievskajae, Viola Ã sukaczewii) from the Asian part of Russia, two (Agrostis sozanensis, Poa mustangensis) from China, two (Carex muskingumensis, Sedum rubens) from Poland, two (Crataegus macrocarpa, Dactylorhiza lapponica) from Romania, two (Oxygraphis delavayi, Ranunculus eryuanensis) from Nepal, two (Erigeron bonariensis, Ophioglossum vulgatum) from Tajikistan, one (Ranunculus olgae) from Kazakhstan, one (Najas guadelupensis) from Hungary, one (Orobanche bartlingii) from Armenia, one (Crataegus petrodavisii) from Azerbaijan and one (Amaranthus powellii) from Georgia. For each species, synonyms, general distribution, habitat preferences, taxonomy with remarks on recognition, and differentiation the species from the most similar taxa occurring in a given country, as well as a list of recorded localities (often far from the previously known areas) are presented

Contribution to the flora of Asian and European countries : new national and regional vascular plant records, 7

The paper presents new records for 29 vascular plant species from 12 Eurasian countries. Seven taxa (Agave sisalana, Austrocylindropuntia subulata, Lagurus ovatus subsp. nanus, Opuntia stricta, Orobanche serbica, Oxalis articulata, Vitis x instabilis) are reported from Albania, one (Allium carinatum) from the Europaean part of Russia, six (Dipsacus fullonum, Gagea shmakoviana, Mentha x dalmatica, Thymus indigirkensis, Thymus sergievskajae, Viola x sukaczewii) from the Asian part of Russia, two (Agrostis sozanensis, Poa mustangensis) from China, two (Carex muskingumensis, Sedum rubens) from Poland, two (Crataegus macrocarpa, Dactylorhiza lapponica) from Romania, two (Oxygraphis delavayi, Ranunculus eryuanensis) from Nepal, two (Erigeron bonariensis, Ophioglossum vulgatum) from Tajikistan, one (Ranunculus olgae) from Kazakhstan, one (Najas guadelupensis) from Hungary, one (Orobanche bartlingii) from Armenia, one (Crataegus petrodavisii) from Azerbaijan and one (Amaranthus powellii) from Georgia. For each species, synonyms, general distribution, habitat preferences, taxonomy with remarks on recognition, and differentiation the species from the most similar taxa occurring in a given country, as well as a list of recorded localities (often far from the previously known areas) are presented