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31.
Aim The biogeography and global distribution of protists has long been disputed, with two primary, opposing views. To test these two sets of views in greater detail, we have compiled the available data for marine benthic ciliates and assessed the general patterns of their diversity and distribution compared with Metazoa. Location World‐wide. Methods A comprehensive database (1342 species, over 350 sources) was used to analyse the diversity, distribution, species occurrences and range size distribution of free‐living ciliates that inhabit marine sediments in 17 geographical regions. Results Twenty‐five per cent of the species have been found in a single region only, whereas 18% are widespread (they occur in more than half the regions covering both hemispheres). Only 5–7% of regional faunas are endemic, which is much lower than for macroorganisms. Regional diversity depends neither on total area nor on coastline length and does not show any obvious latitudinal trends, but correlates highly with the investigation effort expended in a region and (negatively) with the average salinity. A comparison of species composition reveals distinctions between the Arctic Area (the White, Barents and Kara seas), Laurasian Area (north Atlantic, north Pacific and European seas), Gondwanian Area (Southern Ocean) and the Antarctic. No clear geographical correlations are found for faunistic composition at the genus or family levels. There is the tendency to narrow the latitudinal ranges for species found at high latitudes (reversal of Rapoport's rule). Main conclusions Undersampling and data insufficiency are the key factors affecting the observed diversity and distribution of microorganisms. Nevertheless, marine benthic ciliates demonstrate certain patterns that generally agree with the ‘moderate endemicity’ model ( Foissner, 2004, 2008 ), but consistently contradict the regularities commonly observed for multicellular taxa. Thus, ciliates do have a biogeography, but their macroecological patterns may be different in some respects from that of macroorganisms. 相似文献
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Thomas R. Jackson Kristine Salmina Anda Huna Inna Inashkina Eriks Jankevics Una Riekstina Zane Kalnina Andrey Ivanov Paul A. Townsend Mark S. Cragg Jekaterina Erenpreisa 《Cell cycle (Georgetown, Tex.)》2013,12(3):430-431
Comment on: Wu R, et al. Clin Cancer Res 2011; 17:7359–72 相似文献
33.
Sergey M. Abramov Elmira R. Sadraddinova Andrey I. Shestakov Oleg G. Voronin Arkadiy A. Karyakin Nikolay A. Zorin Alexander I. Netrusov 《PloS one》2013,8(11)
Hydrogen-producing thermophilic cellulolytic microorganisms were isolated from cow faeces. Rates of cellulose hydrolysis and hydrogen formation were 0.2 mM L-1 h-1 and 1 mM L-1 h-1, respectively. An enzymatic fuel cell (EFC) with a hydrogenase anode was used to oxidise hydrogen produced in a microbial bioreactor. The hydrogenase electrode was exposed for 38 days (912 h) to a thermophilic fermentation medium. The hydrogenase activity remaining after continuous operation under load was 73% of the initial value. 相似文献
34.
Andrey Skripchenko Helen Awatefe Dedeene Thompson-Montgomery Andrew Myrup Annette Turgeon Stephen J. Wagner 《PloS one》2013,8(8)
Background and Objectives
Platelets during storage undergo diverse alterations collectively known as the platelet storage lesion, including metabolic, morphological, functional and structural changes. Some changes correlate with activation of p38 mitogen activated protein kinase (p38 MAPK). Another MAPK, extracellular signal-related kinase (ERK), is involved in PLT activation. The aim of this study was to compare the properties of platelets stored in plasma in the presence or absence of p38 and ERK MAPK inhibitors.Materials and Methods
A single Trima apheresis platelet unit (n = 12) was aliquoted into five CLX storage bags. Two aliquots were continuously agitated with or without MAPK inhibitors. Two aliquots were subjected to 48 hours of interruption of agitation with or without MAPK inhibitors. One aliquot contained the same amount of solvent vehicle used to deliver the inhibitor. Platelets were stored at 20–24°C for 7 days and sampled on Days 1, 4, and 7 for 18 in vitro parameters.Results
Inhibition of p38 MAPK by VX-702 leads to better maintenance of all platelet in vitro storage parameters including platelet mitochondrial function. Accelerated by interruption of agitation, the platelet storage lesion of units stored with VX-702 was diminished to that of platelets stored with continuous agitation. Inhibition of ERK MAPK did not ameliorate decrements in any in vitro platelet properties.Conclusion
Signaling through p38 MAPK, but not ERK, is associated with platelet deterioration during storage. 相似文献35.
Ilja I. Brusentsov Alexey V. Katokhin Irina V. Brusentsova Sergei V. Shekhovtsov Sergei N. Borovikov Grigoriy G. Goncharenko Lyudmila A. Lider Boris V. Romashov Olga T. Rusinek Samat K. Shibitov Marat M. Suleymanov Andrey V. Yevtushenko Viatcheslav A. Mordvinov 《PloS one》2013,8(4)
Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species. 相似文献
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37.
Resolving the polymorphism-in-probe problem is critical for correct interpretation of expression QTL studies 总被引:1,自引:0,他引:1
Adaikalavan Ramasamy Daniah Trabzuni J. Raphael Gibbs Allissa Dillman Dena G. Hernandez Sampath Arepalli Robert Walker Colin Smith Gigaloluwa Peter Ilori Andrey A. Shabalin Yun Li Andrew B. Singleton Mark R. Cookson for NABEC John Hardy for UKBEC Mina Ryten Michael E. Weale 《Nucleic acids research》2013,41(7):e88
38.
Risto Kerkel? Sara Karsikas Zoltan Szabo Raisa Serpi Johanna Magga Erhe Gao Kari Alitalo Andrey Anisimov Raija Sormunen Ilkka Pietil? Laura Vainio Walter J. Koch Kari I. Kivirikko Johanna Myllyharju Peppi Koivunen 《Molecular and cellular biology》2013,33(16):3321-3329
Small-molecule inhibition of hypoxia-inducible factor prolyl 4-hydroxylases (HIF-P4Hs) is being explored for the treatment of anemia. Previous studies have suggested that HIF-P4H-2 inhibition may also protect the heart from an ischemic insult. Hif-p4h-2gt/gt mice, which have 76 to 93% knockdown of Hif-p4h-2 mRNA in endothelial cells, fibroblasts, and cardiomyocytes and normoxic stabilization of Hif-α, were subjected to ligation of the left anterior descending coronary artery (LAD). Hif-p4h-2 deficiency resulted in increased survival, better-preserved left ventricle (LV) systolic function, and a smaller infarct size. Surprisingly, a significantly larger area of the LV remained perfused during LAD ligation in Hif-p4h-2gt/gt hearts than in wild-type hearts. However, no difference was observed in collateral vessels, while the size of capillaries, but not their number, was significantly greater in Hif-p4h-2gt/gt hearts than in wild-type hearts. Hif-p4h-2gt/gt mice showed increased cardiac expression of endothelial Hif target genes for Tie-2, apelin, APJ, and endothelial nitric oxide (NO) synthase (eNOS) and increased serum NO concentrations. Remarkably, blockage of Tie-2 signaling was sufficient to normalize cardiac apelin and APJ expression and resulted in reversal of the enlarged-capillary phenotype and ischemic cardioprotection in Hif-p4h-2gt/gt hearts. Activation of the hypoxia response by HIF-P4H-2 inhibition in endothelial cells appears to be a major determinant of ischemic cardioprotection and justifies the exploration of systemic small-molecule HIF-P4H-2 inhibitors for ischemic heart disease. 相似文献
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