Biomedical Engineering Reference
In-Depth Information
Fig. 6.2
Motile behavior in a full-moon-shaped keratocyte (Miyoshi and Adachi
2012
). (
a
)
Typical time sequence of phase contrast images showing the cell peripheral movement of a full-
moon-shaped keratocyte. Numbers in
upper right
corner indicate time in seconds. (
b
) Enlarged
images of the
boxed area
in (
a
). Numbers in the
upper right
corner indicate time in seconds. Bars:
(
a
) 10
ʼ
m; (
b
) 1
ʼ
m. Live cell microscopy was performed by mounting a glass-bottom dish on a
temperature-controlled plate at room temperature (20 °C). Timelapse phase contrast images were
acquired using an inverted microscope with a 100 × 1.3 NA Plan objective. Digital 1024 × 1024 pixel
greyscale images of full-moon-shaped keratocytes were captured by an EMCCD camera (Adapted
with permission from The Royal Society of Chemistry: [Integrative Biology], copyright (2012))
6.3.3
Image Processing
In the analysis described here, to characterize cell peripheral dynamics, the cell bound-
aries were extracted from the phase contrast micrographs of the full-moon-shaped
keratocytes. In this section, the method of image processing is explained by citing a
specifi c example.
6.3.3.1
Noise Reduction
The fi rst step of the boundary extraction is noise reduction with an optimal computa-
tional noise fi lter that reduces random fl uctuations in the micrograph while preserving
as much nonrandom features as possible. In the example here, as shown in Fig.
6.3
,
