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21.
Martin Hucík Marek Bučko Peter Gemeiner Vladimír Štefuca Alica Vikartovská Marko D. Mihovilovič Florian Rudroff Naseem Iqbal Dušan ChorvátJr. Igor Lacík 《Biotechnology letters》2010,32(5):675-680
Recombinant Escherichia coli cells, over-expressing cyclopentanone monooxygenase activity, were immobilized in polyelectrolyte complex capsules, made
of sodium alginate, cellulose sulfate, poly(methylene-co-guanidine), CaCl2 and NaCl. More than 90% of the cell viability was preserved during the encapsulation process. Moreover, the initial enzyme
activity was fully maintained within encapsulated cells while it halved in free cells. Both encapsulated and free cells reached
the end point of the Baeyer–Villiger biooxidation of 8-oxabicyclo[3.2.1]oct-6-en-3-one to 4,9-dioxabicyclo[4.2.1]non-7-en-3-one
at the same time (48 h). Similarly, the enantiomeric excess above 94% was identical for encapsulated and free cells. 相似文献
22.
Michael F?ller Ravi S Kasinathan Christophe Duranton Thomas Wieder Stephan M Huber Florian Lang 《Cellular physiology and biochemistry》2006,17(5-6):201-210
Prostaglandin-E2 (PGE2) is known to trigger suicidal death of nucleated cells (apoptosis) and enucleated erythrocytes (eryptosis). In erythrocytes PGE2 induced suicidal cell death involves activation of nonselective cation channels leading to Ca2+ entry followed by cell shrinkage and triggering of Ca2+ sensitive cell membrane scrambling with phosphatidylserine (PS) exposure at the cell surface. The present study was performed to explore whether PGE2 induces apoptosis of nucleated cells similarly through cation channel activation and to possibly disclose the molecular identity of the cation channels involved. To this end, Ca2+ activity was estimated from Fluo3 fluorescence, mitochondrial potential from DePsipher fluorescence, phosphatidylserine exposure from annexin binding, caspase activation from caspAce fluorescence, cell volume from FACS forward scatter, and DNA fragmentation utilizing a photometric enzyme immunoassay. Stimulation of K562 human leukaemia cells with PGE2 (50 microM) increased cytosolic Ca2+ activity, decreased forward scatter, depolarized the mitochondrial potential, increased annexin binding, led to caspase activation and resulted in DNA fragmentation. Gene silencing of the Ca2+-permeable transient receptor potential cation channel TRPC7 significantly blunted PGE2-induced triggering of PS exposure and DNA fragmentation. In conclusion, K562 cells express Ca2+-permeable TRPC7 channels, which are activated by PGE2 and participate in the triggering of apoptosis. 相似文献
23.
Markus Hoffmann Nadine Krüger Pawel Zmora Florian Wrensch Georg Herrler Stefan P?hlmann 《PloS one》2016,11(3)
New World bats have recently been discovered to harbor influenza A virus (FLUAV)-related viruses, termed bat-associated influenza A-like viruses (batFLUAV). The internal proteins of batFLUAV are functional in mammalian cells. In contrast, no biological functionality could be demonstrated for the surface proteins, hemagglutinin (HA)-like (HAL) and neuraminidase (NA)-like (NAL), and these proteins need to be replaced by their human counterparts to allow spread of batFLUAV in human cells. Here, we employed rhabdoviral vectors to study the role of HAL and NAL in viral entry. Vectors pseudotyped with batFLUAV-HAL and -NAL were able to enter bat cells but not cells from other mammalian species. Host cell entry was mediated by HAL and was dependent on prior proteolytic activation of HAL and endosomal low pH. In contrast, sialic acids were dispensable for HAL-driven entry. Finally, the type II transmembrane serine protease TMPRSS2 was able to activate HAL for cell entry indicating that batFLUAV can utilize human proteases for HAL activation. Collectively, these results identify viral and cellular factors governing host cell entry driven by batFLUAV surface proteins. They suggest that the absence of a functional receptor precludes entry of batFLUAV into human cells while other prerequisites for entry, HAL activation and protonation, are met in target cells of human origin. 相似文献
24.
Carina Hüwe Jennifer Schmeichel Florian Brodkorb Sophia Dohlen Katrin Kalbfleisch Martin Kreyenschmidt 《Biofouling》2018,34(4):378-387
Antimicrobial surfaces are one approach to prevent biofilms in the food industry. The aim of this study was to investigate the effect of poly((tert-butyl-amino)-methyl-styrene) (poly(TBAMS)) incorporated into linear low-density polyethylene (LLDPE) on the formation of mono- and mixed-species biofilms. The biofilm on untreated and treated LLDPE was determined after 48 and 168 h. The comparison of the results indicated that the ability of Listeria monocytogenes to form biofilms was completely suppressed by poly(TBAMS) (Δ168 h 3.2 log10 cfu cm?2) and colonization of Staphylococcus aureus and Escherichia coli was significantly delayed, but no effect on Pseudomonas fluorescens was observed. The results of dual-species biofilms showed complex interactions between the microorganisms, but comparable effects on the individual bacteria by poly(TBAMS) were identified. Antimicrobial treatment with poly(TBAMS) shows great potential to prevent biofilms on polymeric surfaces. However, a further development of the material is necessary to reduce the colonization of strong biofilm formers. 相似文献
25.
26.
Damien Formey Erika Sallet Christine Lelandais-Brière Cécile Ben Pilar Bustos-Sanmamed Andreas Niebel Florian Frugier Jean Philippe Combier Frédéric Debellé Caroline Hartmann Julie Poulain Frédérick Gavory Patrick Wincker Christophe Roux Laurent Gentzbittel Jér?me Gouzy Martin Crespi 《Genome biology》2014,15(9)
27.
Leuschner F Dutta P Gorbatov R Novobrantseva TI Donahoe JS Courties G Lee KM Kim JI Markmann JF Marinelli B Panizzi P Lee WW Iwamoto Y Milstein S Epstein-Barash H Cantley W Wong J Cortez-Retamozo V Newton A Love K Libby P Pittet MJ Swirski FK Koteliansky V Langer R Weissleder R Anderson DG Nahrendorf M 《Nature biotechnology》2011,29(11):1005-1010
Excessive and prolonged activity of inflammatory monocytes is a hallmark of many diseases with an inflammatory component. In such conditions, precise targeting of these cells could be therapeutically beneficial while sparing many essential functions of the innate immune system, thus limiting unwanted effects. Inflammatory monocytes-but not the noninflammatory subset-depend on the chemokine receptor CCR2 for localization to injured tissue. Here we present an optimized lipid nanoparticle and a CCR2-silencing short interfering RNA that, when administered systemically in mice, show rapid blood clearance, accumulate in spleen and bone marrow, and localize to monocytes. Efficient degradation of CCR2 mRNA in monocytes prevents their accumulation in sites of inflammation. Specifically, the treatment attenuates their number in atherosclerotic plaques, reduces infarct size after coronary artery occlusion, prolongs normoglycemia in diabetic mice after pancreatic islet transplantation, and results in reduced tumor volumes and lower numbers of tumor-associated macrophages. 相似文献
28.
Cotar Ani Ioana Falcuta Elena Prioteasa Liviu Florian Dinu Sorin Ceianu Cornelia Svetlana Paz Shlomit 《EcoHealth》2016,13(4):796-807
EcoHealth - Mosquitoes were collected in the Danube Delta during the active seasons of 2011–2013. For Culex spp. mosquitoes, the abundance was calculated. Culex pipiens (sensu lato), (s.l.)... 相似文献
29.
30.
Daniela Niemeyer Thomas Zillinger Doreen Muth Florian Zielecki Gabor Horvath Tasnim Suliman Winfried Barchet Friedemann Weber Christian Drosten Marcel A. Müller 《Journal of virology》2013,87(22):12489-12495
Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe acute respiratory infection with as yet unclear epidemiology. We previously showed that MERS-CoV counteracts parts of the innate immune response in human bronchiolar cells. Here we analyzed accessory proteins 3, 4a, 4b, and 5 for their abilities to inhibit the type I interferon response. Accessory protein 4a was found to block interferon induction at the level of melanoma differentiation-associated protein 5 (MDA5) activation presumably by direct interaction with double-stranded RNA. 相似文献