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This study aimed to investigate the in vitro damage induced by ochratoxin A (OTA) in BME-UV1 and MDCK epithelial cells. Both cells lines were treated with OTA (0 up to 10 μg/mL), and cell viability (MTT assay), membrane stability (lactate dehydrogenase (LDH) release assay) and apoptotic cell rate (Tunel assay) were investigated. Further, the effect of the incubation with OTA has been evaluated at DNA level by the determination of DNA integrity, by the quantification of DNA adduct formation (8-hydroxy-2′-deoxyguanosine (8-OHdG)) and by the assessment of the global DNA methylation status (5-methyl-cytosine (5-mC)). The obtained results showed that after 24 h of OTA treatment, BME-UV1 cell viability was reduced in a dose-dependent way. OTA significantly (P?<?0.05) increased LDH release in BME-UV1 cells at all concentrations tested. OTA (1.25 μg/mL) induced 35 % LDH release in MDCK cells (P?<?0.05). A significant (P?<?0.05) change in percentages of apoptotic BME-UV1 (10?±?0.86) and MDCK (25?±?0.88) cells was calculated when the cells were co-incubated with OTA. The level of 8-OHdG adduct formation was significantly (P?<?0.05) increased in BME-UV1 cells treated with 1.25 μg/mL of OTA. The results of the present study suggest that a different mechanism of action may occur in these cell lines.
Graphical abstract Study results overview
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43.
The results of the study of 21 populations of Siberian spruce (Picea obovata Ledeb.) from different parts of the species natural range by microsatellite (SSR) analysis of nuclear DNA are presented. Using nine loci developed for Picea abies (L.) Karst. and Picea glauca (Moench) Voss and detecting variation in Picea obovata, the parameters of intra- and interpopulation genetic diversity, as well as the degree of population differentiation, were determined. It was demonstrated that the population of Siberian spruce in the study was characterized by a relatively high average level of intrapopulation variability (Ho = 0.408; He = 0.423) and low interpopulation differentiation (Fst = 0.048, P = 0.001) at this class of DNA markers. The genetic distance between populations ranged from 0.009 to 0.167, averaging 0.039. The isolated Magadan population, located in the extreme Northeast of Russia at a considerable distance from the main species range and characterized by the lowest genetic diversity among the studied populations, was maximally differentiated from the rest of the spruce populations. In addition, the steppe Ubukun population from Buryatia and the population from the Bogd Khan Uul Biosphere Reserve, Mongolia, were considerably different in the genetic structure from most populations of Siberian spruce, although to a lesser extent than the Magadan population. These findings are consistent with the results of previous studies of this species carried out using allozyme and microsatellite loci of chloroplast DNA and point to the prospects of using nuclear microsatellites as DNA markers to analyze the population genetic structure of Siberian spruce.  相似文献   
44.
The variability of 21 allozyme and three microsatellite loci of chloroplast DNA (cpDNA) was studied in the populations of Siberian spruce (Picea obovata Ledeb.) from Irkutsk oblast, Magadan oblast, Buryatia, and Mongolia. It was demonstrated that the highest level of genetic diversity among the examined populations at both allozyme and microsatellite loci was observed in the Tulyushka population from Irkutsk oblast. The lowest level of genetic diversity was observed in marginal isolated populations of Bogd Uul and Magadan. In the relict spruce population from Olkhon Island, differing from the other populations in the lowest allelic diversity of both types of markers, no expected decline of expected heterozygosity and haplotype diversity was observed. In this population, the variability parameters mentioned were close to the population mean. The obtained intrapopulation and intraspecific variability parameters of allozyme and microsatellite loci of chloroplast DNA and the data on the population differentiation at these loci indicate that the given markers can be used for the analysis of the population structure of Siberian spruce.  相似文献   
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Invasive species can encounter environments different from their source populations, which may trigger rapid adaptive changes after introduction (niche shift hypothesis). To test this hypothesis, we investigated whether postintroduction evolution is correlated with contrasting environmental conditions between the European invasive and source ranges in the Asian tiger mosquito Aedes albopictus. The comparison of environmental niches occupied in European and source population ranges revealed more than 96% overlap between invasive and source niches, supporting niche conservatism. However, we found evidence for postintroduction genetic evolution by reanalyzing a published ddRADseq genomic dataset from 90 European invasive populations using genotype–environment association (GEA) methods and generalized dissimilarity modeling (GDM). Three loci, among which a putative heat‐shock protein, exhibited significant allelic turnover along the gradient of winter precipitation that could be associated with ongoing range expansion. Wing morphometric traits weakly correlated with environmental gradients within Europe, but wing size differed between invasive and source populations located in different climatic areas. Niche similarities between source and invasive ranges might have facilitated the establishment of populations. Nonetheless, we found evidence for environmental‐induced adaptive changes after introduction. The ability to rapidly evolve observed in invasive populations (genetic shift) together with a large proportion of unfilled potential suitable areas (80%) pave the way to further spread of Ae. albopictus in Europe.  相似文献   
47.
The effects of potassium chloride on the expression of IGF-1 splice forms and myoblast proliferation were investigated. KCl at the concentrations of 7–12 mM stimulated the synthesis of IGF-1 and mechano growth factor (MGF) in murine myoblasts as well as in myotubes both at the mRNA and protein levels. Pan-calcium channel blocker CdCl2 completely abolished stimulation of growth factor expression, whereas blocker of HCN and Nav1.4 channels ZD7288 drastically reduced it. In addition, potassium chloride stimulated myoblast proliferation, while IGF-1 autocrine signaling inhibition partially suppressed these mitogenic effects.  相似文献   
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Tikhonova  E. N.  Men’ko  E. V.  Ulanova  R. V.  Li  H.  Kravchenko  I. K. 《Microbiology》2019,88(6):781-785
Microbiology - Effect of temperature on succession changes of the saprotrophic bacterial community of gray forest soil in the course of decomposition of aspen leaves and branches was studied in...  相似文献   
50.
Journal of Ichthyology - Based on materials from bottom trawl surveys of 2009–2015, biomass and abundance of bottom fish of the Sea of ​​Japan between the Povorotny and Zolotoy...  相似文献   
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