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11.
Grosse J Wehland M Pietsch J Ma X Ulbrich C Schulz H Saar K Hübner N Hauslage J Hemmersbach R Braun M van Loon J Vagt N Infanger M Eilles C Egli M Richter P Baltz T Einspanier R Sharbati S Grimm D 《FASEB journal》2012,26(2):639-655
This study focused on the effects of short-term microgravity (22 s) on the gene expression and morphology of endothelial cells (ECs) and evaluated gravisensitive signaling elements. ECs were investigated during four German Space Agency (Deutsches Zentrum für Luft- und Raumfahrt) parabolic flight campaigns. Hoechst 33342 and acridine orange/ethidium bromide staining showed no signs of cell death in ECs after 31 parabolas (P31). Gene array analysis revealed 320 significantly regulated genes after the first parabola (P1) and P31. COL4A5, COL8A1, ITGA6, ITGA10, and ITGB3 mRNAs were down-regulated after P1. EDN1 and TNFRSF12A mRNAs were up-regulated. ADAM19, CARD8, CD40, GSN, PRKCA (all down-regulated after P1), and PRKAA1 (AMPKα1) mRNAs (up-regulated) provide a very early protective mechanism of cell survival induced by 22 s microgravity. The ABL2 gene was significantly up-regulated after P1 and P31, TUBB was slightly induced, but ACTA2 and VIM mRNAs were not changed. β-Tubulin immunofluorescence revealed a cytoplasmic rearrangement. Vibration had no effect. Hypergravity reduced CARD8, NOS3, VASH1, SERPINH1 (all P1), CAV2, ADAM19, TNFRSF12A, CD40, and ITGA6 (P31) mRNAs. These data suggest that microgravity alters the gene expression patterns and the cytoskeleton of ECs very early. Several gravisensitive signaling elements, such as AMPKα1 and integrins, are involved in the reaction of ECs to altered gravity. 相似文献
12.
Kasari M Padrik P Vaasa A Saar K Leppik K Soplepmann J Uri A 《Analytical biochemistry》2012,422(2):79-88
A novel nonmetal optical probe ARC-1063 whose long-lifetime luminescence is induced by association with the target protein kinase is used for the measurement of the concentration of catalytic subunit of protein kinase A (PKAc) in complicated biological solutions. High affinity (K(D) = 10 pM toward PKAc) and unique optical properties of the probe enable its application for the measurement of picomolar concentrations of PKAc in the presence of high concentrations of other proteins. The described assay is applicable in the high-throughput format with the instrument setups designed for lanthanide-based time-gated (time-resolved) luminescence methods. The assay is used for demonstration that extracellular PKAc (ECPKA) is present in plasma samples of all healthy persons and cancer patients but great care must be taken for procedures of treatment of blood samples to avoid disruption, damage, or activation of platelets in the course of plasma (or serum) preparation and conservation. 相似文献
13.
Guo W Schafer S Greaser ML Radke MH Liss M Govindarajan T Maatz H Schulz H Li S Parrish AM Dauksaite V Vakeel P Klaassen S Gerull B Thierfelder L Regitz-Zagrosek V Hacker TA Saupe KW Dec GW Ellinor PT MacRae CA Spallek B Fischer R Perrot A Özcelik C Saar K Hubner N Gotthardt M 《Nature medicine》2012,18(5):766-773
14.
The biodegradable oil absorption resin (B-PEHA) was prepared by suspension polymerization, and its preparation was confirmed by Fourier transform infrared analysis. The oil absorption capacities of the prepared B-PEHA were: chloroform 30.88, toluene 19.75, xylene, 18.78, THF 15.96, octane 11.43, hexane 9.5, diesel oil 12.80, and kerosene 13.79 g/g. The biodegradation of the prepared B-PEHA was also investigated by determination of reduced sugar produced after enzymatic hydrolysis, thermogravimetric analysis, and incubation with Aspergillus niger. The biodegradation of B-PEHA was ~18%. 相似文献
15.
Real-time determination of kinetics of adsorption of lead(II) onto palm shell-based activated carbon using ion selective electrode 总被引:2,自引:0,他引:2
In this study, the kinetics of adsorption of Pb(II) from aqueous solution onto palm shell-based activated carbon (PSAC) were investigated by employing ion selective electrode (ISE) for real-time Pb(II) and pH monitoring. Usage of ISE was very appropriate for real-time adsorption kinetics data collection as it facilitated recording of adsorption data at very specific and short time intervals as well as provided consistent kinetics data. Parameters studied were initial Pb(II) concentration and agitation speed. It was found that increases in initial Pb(II) concentration and agitation speed resulted in higher initial rate of adsorption. Pseudo first-order, pseudo second-order, Elovich, intraparticle diffusion and liquid film diffusion models were used to fit the adsorption kinetics data. It was suggested that chemisorption was the rate-controlling step for adsorption of Pb(II) onto PSAC since the adsorption kinetics data fitted both the pseudo second-order and Elovich models well. 相似文献
16.
Dayle E. Saar Neil O. Polans Paul D. Sørensen Melvin R. Duvall 《Plant Molecular Biology Reporter》2001,19(3):249-260
PCR primers with broad applicability are useful in many molecular-based studies; however, their universality can compromise
results when DNA contaminants also are amplified. Eighty-one templates ofDahlia (Asteraceae), primarily extracted from native Mexican populations, were tested for the presence of fungal contaminants; out
of these, almost 1 in 7 templates (13.6%) was contaminated. In a second survey across 12 angiosperm families using material
collected in Illinois, fungal DNA contaminated over 60% of the templates analyzed. Endophytic fungi often are symptomless
symbionts living within the above-ground tissues of their angiosperm hosts and are not affected by surface sterilization techniques.
Recent studies have revealed their widespread occurrence and broad host range. We also present field strategies for obtaining
plant material to reduce the possibility of collecting infected leaves and a simple screening test for detecting fungal DNA
in angiosperm templates. 相似文献
17.
Tor Erik Brandrud Geert Schmidt-Stohn Kare Liimatainen Tuula Niskanen Tobias Guldberg Frøslev Karl Soop Dimitar Bojantchev Ilkka Kytövuori Thomas Stjernegaard Jeppesen Francesco Bellù Günter Saar Bernhard Oertel Tahir Ali Marco Thines Bálint Dima 《Mycological Progress》2018,17(12):1323-1354
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests 相似文献
18.
M H?llbrink K Saar C G Ostenson U Soomets S Efendic J Howl M Wheatley M Zorko U Langel 《Regulatory peptides》1999,82(1-3):45-51
Two chimeric peptides, consisting of the linear vasopressin receptor V1 antagonist PhAc-D-Tyr(Me)-Phe-Gln-Asn-Arg-Pro-Arg-Tyr, in the N-terminus and mastoparan in the C-terminus connected directly (M375) or via 6-aminohexanoic acid (M391), have been synthesised. At 10 microM concentration, these novel peptides increased insulin secretion from isolated rat pancreatic islet cells 18-26-fold at 3.3 mM glucose and 3.5-5-fold at 16.7 mM glucose. PTX pretreatment of the islets decreased the peptide-induced insulin release. M375 and M391 bind to V1a vasopressin receptors with affinities lower than the unmodified vasopressin antagonist, but with K(D) values of 3.76 nM and 9.02 nM, respectively, both chimeras are high affinity ligands. The GTPase activity and GTPgammaS binding in the presence of these peptides has been characterised in Rin m5F cells. Comparison of the influence of the peptides M375 and M391 on GTPase activity in native and pertussis toxin-treated cells suggests a selective activation of G alpha(i)/G alpha(o) subunits, combined with a suppression of other GTPases, primarily G alpha(s). However, the GTPgammaS binding data show that the peptides retain some of the activating property even in PTX-treated cell membranes. In conclusion, the conjugation of mastoparan with the V1a receptor antagonists produce peptides with properties different from the parent peptides that could be used to elucidate the role of different G proteins in insulin release. 相似文献
19.
Carolina Reyes Dominik Schneider Andrea Thürmer Ajinkya Kulkarni Marko Lipka Saar Y. Sztejrenszus 《Geomicrobiology journal》2017,34(10):840-850
In many marine surface sediments, the reduction of manganese (Mn) and iron (Fe) oxides is obscured by sulfate reduction, which is regarded as the predominant anaerobic microbial respiration process. However, many dissimilatory sulfate and sulfur reducing microorganisms are known to utilize alternative electron acceptors such as metal oxides. In this study, we tested whether sulfate and sulfur reducing bacteria are linked to metal oxide reduction based on biogeochemical modeling of porewater concentration profiles of Mn2+ and Fe2+ in Bothnian Bay (BB) and Skagerrak (SK) sediments. Steady-state modeling of Fe2+ and Mn2+ porewater profiles revealed zones of net Fe (0–9 cm BB; ~10 and 20 cm SK) and Mn (0–5 cm BB; 2–8 cm SK) species transformations. 16S rRNA pyrosequencing analysis of the in-situ community showed that Desulfobacteraceae, Desulfuromonadaceae and Desulfobulbaceae were present in the zone of Fe-reduction of both sediments. Rhodobacteraceae were also detected at high relative abundance in both sediments. BB sediments appeared to harbor a greater diversity of potential Fe-reducers compared to SK. Additionally, when the upper 10 cm of sediment from the SK was incubated with lepidocrocite and acetate, Desulfuromonas was the dominant bacteria. Real-time quantitative polymerase chain reaction (qPCR) results showed decreasing dsrA gene copy numbers with depth coincided with decreased Fe-reduction activity. Our results support the idea that sulfur and sulfate reducing bacteria contribute to Fe-reduction in the upper centimeters of both sediments. 相似文献
20.