Stained cells were observed using Olympus motorized revolving AX 70 system microscope (Olympus Optical, Hamburg,

Germany) coupled with 12 bits Sensicam digital image camera (Sensicam, Kelheim, Germany) and analyzed using the Analysis Pro 3.0 image analysis and processing system (Soft-Imaging Software GmbH, Munster, Germany). Acknowledgements We thank Eija Kaila and Erkki Hänninen for their DZNeP concentration technical help. Supported by Finnish Medical Foundation, EVO clinical research grants, Finska Läkaresällskapet, Stockmann Foundation, and the Centre for Technological Advancement (TEKES), Invalid Foundation, University of Helsinki Group of Excellence scheme, and the PhD Graduate School on Biomaterials and Tissue Engineering of the Ministry of Education. References 1. Lamb RA, Paterson RG, Jardetzky TS: Paramyxovirus membrane fusion: lessons from the F and OTX015 chemical structure HN atomic structures. Virology 2006, 344:30–7.CrossRefPubMed 2. Moscona A: Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 2005, 115:1688–1698.CrossRefPubMed 3. Daya M, Cervin M, Anderson R: Cholesterol enhances mouse hepatitis

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