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A. S. Bashkuev 《Paleontological Journal》2008,42(4):401-405
Two new species and a new genus of scorpionflies of the family Kaltanidae, Pseudochorista occidentalis sp. nov. and Kamochorista novokshonovi gen. et sp. nov. (Mecoptera: Kaltanidae), are described from the Urzhumian of Udmurtia (Chepanikha locality). This is the first record of kaltanids on the Russian Platform. 相似文献
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Halley Shah Adam M Speen Christina Saunders Elizabeth AS Brooke Palanisamy Nallasamy Hong Zhu Y Robert Li Zhenquan Jia 《Experimental biology and medicine (Maywood, N.J.)》2015,240(10):1340-1351
Acrolein is an environmental toxicant, mainly found in smoke released from incomplete combustion of organic matter. Several studies showed that exposure to acrolein can lead to liver damage. The mechanisms involved in acrolein-induced hepatocellular toxicity, however, are not completely understood. This study examined the cytotoxic mechanisms of acrolein on HepG2 cells. Acrolein at pathophysiological concentrations was shown to cause apoptotic cell death and an increase in levels of protein carbonyl and thiobarbituric acid reactive acid substances. Acrolein also rapidly depleted intracellular glutathione (GSH), GSH-linked glutathione-S-transferases, and aldose reductase, three critical cellular defenses that detoxify reactive aldehydes. Results further showed that depletion of cellular GSH by acrolein preceded the loss of cell viability. To further determine the role of cellular GSH in acrolein-mediated cytotoxicity, buthionine sulfoximine (BSO) was used to inhibit cellular GSH biosynthesis. It was observed that depletion of cellular GSH by BSO led to a marked potentiation of acrolein-mediated cytotoxicity in HepG2 cells. To further assess the contribution of these events to acrolein-induced cytotoxicity, triterpenoid compound 2-cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) was used for induction of GSH. Induction of GSH by CDDO-Im afforded cytoprotection against acrolein toxicity in HepG2 cells. Furthermore, BSO significantly inhibited CDDO-Im-mediated induction in cellular GSH levels and also reversed cytoprotective effects of CDDO-Im in HepG2 cells. These results suggest that GSH is a predominant mechanism underlying acrolein-induced cytotoxicity as well as CDDO-Im-mediated cytoprotection. This study may provide understanding on the molecular action of acrolein which may be important to develop novel strategies for the prevention of acrolein-mediated toxicity. 相似文献
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Alexei Bashkuev Jürgen Sell Daniil Aristov Alexandr Ponomarenko Nina Sinitshenkova Horst Mahler 《Pal?ontologische Zeitschrift》2012,86(2):175-185
Upper Buntsandstein deposits (mainly Myophoria beds, R?t Formation, Early Anisian) in Lower Franconia and Thuringia have yielded a rather rich insect fauna comprising ca. 300 insect specimens assigned to ten orders: Archaeognatha (Dasyleptidae), Ephemeroptera, Blattodea, Grylloblattida, Orthoptera, Hemiptera, Glosselytrodea, Coleoptera, Mecoptera and Diptera. The systematic list of recorded insects is provided. Two species are identified as Triassodotes vogesiacus Sinitshenkova, Marchal-Papier, Grauvogel-Stamm et Gall, 2005 (Ephemeroptera: Misthodotidae) and Pseudopolycentropus triasicus Papier, Nel et Grauvogel-Stamm, 1996 (Mecoptera), which were previously described from the ??Grès à Voltzia?? Formation of the Vosges, the stratigraphically closest insect fauna. All grylloblattid specimens are identified as Chauliodites picteti Heer, 1864 (Chaulioditidae), known previously from the Middle Buntsandstein of G?dewitz, Saxony-Anhalt. The new genus and species Hammephemera pulchra Sinitshenkova, gen. et sp. n. (Ephemeroptera: Sharephemeridae) is described. 相似文献
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JOSÉ ARTURO ALCÁNTARA‐RODRÍGUEZ JORGE CIROS‐PÉREZ ELIZABETH ORTEGA‐MAYAGOITIA CARMEN R. SERRANIA‐SOTO ELÍAS PIEDRA‐IBARRA 《Freshwater Biology》2012,57(4):728-740
1. Salinity is a strong selective force for many aquatic organisms, affecting both ecological and evolutionary processes. Most of our knowledge on the effects of salinity on rotifers in the Brachionus plicatilis species complex is based mainly on populations from waterbodies that experience broad environmental changes both seasonally and annually. We tested the hypothesis that, despite the supposedly high potential for gene flow among rotifers inhabiting neighbouring environments, constant salinity has promoted local adaptation, genetic population divergence and even cryptic speciation in B. plicatilis complex populations from three deep maar lakes of distinct salinities [1.1, 6.5 and 9.0 g L?1 total dissolved solids (TDS)] in Central Mexico. 2. To look for local adaptation, we performed common garden experiments to test the effect of different salinities on population density and intrinsic growth rate (r). Then, we evaluated the genetic divergence by sequencing the cytochrome c oxidase subunit I (COI) gene and performed reproductive trials to assess the potential gene flow among the three populations and with other closely related B. plicatilis complex species. 3. We confirmed that the rotifer populations have phenotypic plasticity in tolerance of salinity, but only rotifers from the least saline lake are adapted to low salinity. Among the populations, sequence divergence at COI was very low (just a single haplotype was found), suggesting a persistent founder effect from a relatively recent single colonisation event and a subsequent dispersal from one lake to the others, and a very restricted immigration rate. In the phylogenetic analysis, rotifers from this area of Mexico clustered in the same clade with the middle‐sized species Brachionus ibericus and B. sp. ‘Almenara’. Mexican rotifers showed successful recognition, copulation and formation of hybrids among them, but interpopulation breeding with the Spanish B. ibericus and B. sp. ‘Almenara’ was unsuccessful. 4. We conclude that the B. plicatilis complex populations from these three lakes belong to a new biological species not yet described (presently named B. sp. ‘Mexico’). To our knowledge, this is the first report of local adaptation of a natural B. plicatilis complex population living in freshwater conditions (1.1 g L?1 TDS). 相似文献
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Eliana Alves Liliana Costa Carla MB Carvalho Jo?o PC Tomé Maria A Faustino Maria GPMS Neves Augusto C Tomé José AS Cavaleiro ?ngela Cunha Adelaide Almeida 《BMC microbiology》2009,9(1):70