TY - JOUR T1 - Observation of Live Ticks (Haemaphysalis flava) by Scanning Electron Microscopy under High Vacuum Pressure A1 - Ishigaki, Yasuhito A1 - Nakamura, Yuka A1 - Oikawa, Yosaburo A1 - Yano, Yasuhiro A1 - Kuwabata, Susumu A1 - Nakagawa, Hideaki A1 - Tomosugi, Naohisa A1 - Takegami, Tsutomu Y1 - 2012/03/14 N2 - Scanning electron microscopes (SEM), which image sample surfaces by scanning with an electron beam, are widely used for steric observations of resting samples in basic and applied biology. Various conventional methods exist for SEM sample preparation. However, conventional SEM is not a good tool to observe living organisms because of the associated exposure to high vacuum pressure and electron beam radiation. Here we attempted SEM observations of live ticks. During 1.5×10−3 Pa vacuum pressure and electron beam irradiation with accelerated voltages (2–5 kV), many ticks remained alive and moved their legs. After 30-min observation, we removed the ticks from the SEM stage; they could walk actively under atmospheric pressure. When we tested 20 ticks (8 female adults and 12 nymphs), they survived for two days after SEM observation. These results indicate the resistance of ticks against SEM observation. Our second survival test showed that the electron beam, not vacuum conditions, results in tick death. Moreover, we describe the reaction of their legs to electron beam exposure. These findings open the new possibility of SEM observation of living organisms and showed the resistance of living ticks to vacuum condition in SEM. These data also indicate, for the first time, the usefulness of tick as a model system for biology under extreme condition. JF - PLOS ONE JA - PLOS ONE VL - 7 IS - 3 UR - https://doi.org/10.1371/journal.pone.0032676 SP - e32676 EP - PB - Public Library of Science M3 - doi:10.1371/journal.pone.0032676 ER -