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101.
Patrick Stelmach Christian Wedemeyer Lena Fuest Gina Kurscheid Thorsten Gehrke Stefanie Klenke Marcus J?ger Max D. Kauther Hagen S. Bachmann 《PloS one》2016,11(2)
Aseptic loosening is a major cause of revision surgery of total hip arthroplasty (THA). Only few host factors affecting aseptic loosening have been identified until now, although they are urgently needed to identify and possibly treat those patients at higher risk for aseptic loosening. To determine whether the functional single nucleotide polymorphism (SNP) c.-938C>A (rs2279115), located in the promoter region of the BCL2 gene has an impact on aseptic loosening of THA we genotyped and analyzed 234 patients suffering from aseptic loosening and 231 patients after primary THA. The polymorphism is associated with risk for aseptic loosening with the CC genotype at highest risk for aseptic loosening, Odds Ratio CC vs. AA 1.93, 95%CI 1.15–3.25, p = 0.013. In contrast, low risk AA genotype carriers that still developed aseptic loosening showed a significantly shorter time to aseptic loosening than patients carrying the C allele (p = 0.004). These results indicate that the BCL2 -938C>A polymorphism influences the occurrence and course of aseptic loosening and suggests this polymorphism as an interesting candidate for prospective studies and analyses in THA registers. 相似文献
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Sharp KH Schneider S Cockayne A Paoli M 《The Journal of biological chemistry》2007,282(14):10625-10631
Pathogens such as Staphylococcus aureus require iron to survive and have evolved specialized proteins to steal heme from their host. IsdC is the central conduit of the Isd (iron-regulated surface determinant) multicomponent heme uptake machinery; staphylococcal cell-surface proteins such as IsdA, IsdB, and IsdH are thought to funnel their molecular cargo to IsdC, which then mediates the transfer of the iron-containing nutrient to the membrane translocation system IsdDEF. The structure of the heme-IsdC complex reveals a novel heme site within an immunoglobulin-like domain and sheds light on its binding mechanism. The folding topology is reminiscent of the architecture of cytochrome f, cellobiose dehydrogenase, and ethylbenzene dehydrogenase; in these three proteins, the heme is bound in an equivalent position, but interestingly, IsdC features a distinct binding pocket with the ligand located next to the hydrophobic core of the beta-sandwich. The iron is coordinated with a tyrosine surrounded by several non-polar side chains that cluster into a tightly packed proximal side. On the other hand, the distal side is relatively exposed with a short helical peptide segment that acts as a lip clasping onto almost half of the porphyrin plane. This structural feature is argued to play a role in the mechanism of binding and release by switching to an open conformation and thus loosening the interactions holding the heme. The structure of the heme-IsdC complex provides a template for the understanding of other proteins, such as IsdA, IsdB, and IsdH, that contain the same heme-binding module as IsdC, known as the NEAT (near transporter) domain. 相似文献
105.
Xing De Su Baofeng Li Shangjia Bangs Max Creamer David Coogan Michael Wang Jinhai Simora Rhoda Ma Xiaoli Hettiarachchi Darshika Alston Veronica Wang Wenwen Johnson Andrew Lu Cuiyu Hasin Tasnuba Qin Zhenkui Dunham Rex 《Marine biotechnology (New York, N.Y.)》2022,24(3):513-523
Marine Biotechnology - Omega-3 polyunsaturated fatty acids (n-3 PUFAs), particularly eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), play a very important role in... 相似文献
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Alex A. Pollen Aparna Bhaduri Madeline G. Andrews Tomasz J. Nowakowski Olivia S. Meyerson Mohammed A. Mostajo-Radji Elizabeth Di Lullo Beatriz Alvarado Melanie Bedolli Max L. Dougherty Ian T. Fiddes Zev N. Kronenberg Joe Shuga Anne A. Leyrat Jay A. West Marina Bershteyn Craig B. Lowe Bryan J. Pavlovic Arnold R. Kriegstein 《Cell》2019,176(4):743-756.e17
108.
Jens G. P. Diller Sophia Drescher Mario Hofmann Max Rabus Heike Feldhaar Christian Laforsch 《Ecology and evolution》2022,12(4)
Invasive alien species are a major threat to ecosystems. Invasive terrestrial plants can produce allelochemicals which suppress native terrestrial biodiversity. However, it is not known if leached allelochemicals from invasive plants growing in riparian zones, such as Impatiens glandulifera, also affect freshwater ecosystems. We used mesocosms and laboratory experiments to test the impact of I. glandulifera on a simplified freshwater food web. Our mesocosm experiments show that leachate from I. glandulifera significantly reduced population growth rate of the water flea Daphnia magna and the green alga Acutodesmus obliquus, both keystone species of lakes and ponds. Laboratory experiments using the main allelochemical released by I. glandulifera, 2‐methoxy‐1,4‐naphthoquinone, revealed negative fitness effects in D. magna and A. obliquus. Our findings show that allelochemicals from I. glandulifera not only reduce biodiversity in terrestrial habitats but also pose a threat to freshwater ecosystems, highlighting the necessity to incorporate cross‐ecosystem effects in the risk assessment of invasive species. 相似文献
109.
Anna Schorcht Christopher A. Cottrell Pavel Pugach Rajesh P. Ringe Alvin X. Han Joel D. Allen Tom L. G. M. van den Kerkhof Gemma E. Seabright Edith E. Schermer Thomas J. Ketas Judith A. Burger Jelle van Schooten Celia C. LaBranche Gabriel Ozorowski Natalia de Val Daniel L. V. Bader Hanneke Schuitemaker Colin A. Russell David C. Montefiori Marit J. van Gils Max Crispin P. J. Klasse Andrew B. Ward John P. Moore Rogier W. Sanders 《Journal of virology》2022,96(1)
110.
Max M. Tilzer Anna Hillbricht-Ilkowska Andrzej Kowalczewski Irena Spodniewska Joanna Turczyska 《International Review of Hydrobiology》1977,62(2):279-289
Photosynthetic rates as measured by the oxygen light and dark bottle method were highly correlated with estimates using the 14C technique. The high O2/14C ratios found are explained by algal respiration and extracellular release which are included in photosynthetic measurements by the oxygen technique, while the 14C method yields values close to net photosynthesis. Separation of net- and nannoplankton using a 50 μm plankton net for filtration was not comparable to distinctions made by microscopic examination. Separation of both by filtration caused a significant decrease in the photosynthetic activity of nannoplankton in 24-hour incubations, but had no detectable effect after 4 hours of exposure. “Bottle effects” in 24-hour measurements of photosynthesis were similar using both methods. Asymmetric photosynthetic time-curves as well as vertical phytoplankton migrations were the main reasons for errors in estimates of daily photosynthetic rates from part-day incubations which were extrapolated to the entire day. 相似文献