undecalcified bone frozens

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From:Gayle Callis <uvsgc@msu.oscs.montana.edu>
Date:Thu, 03 Jun 1999 10:32:38 -0600

The tape transfer system is JUST an OPTION.  Have sectioned bone both
ways, with the Instrumedics and without it.

You still need to use a tungsten carbide knife, have used both D and
C profile tungsten carbide cryostat knives, in a conventional (Leica 
cryocut 1800) cryostat.  If you do not do tape transfer, I had to use the 
antiroll device, and section at -32c to -35C.  I found dry ice cooling of the
the blade gave me crunched sections, even though it worked very well in
Dodds undecalcified bone frozen workshop in an automated Hacker Bright 
cryostat (mine is not automated, manual model) with a C profile TC knife.
Also the bones we cut in that workshop were small - half of a mouse tibia.

The D profile worked best, with antiroll device in my Leica, and the knife
must be sharp!!!  There is a way to do this
without sticky tape, using lens paper dipped in 4% PVA (Sigma 30,000 to 70,000
MW, water soluble, stripping the excess PVA out between fingers, applying this
to face of block, roll with a rounded pencil, section, the section sticks
to this strip, go to slide, lay it on slide, warm slide with back of hand,
do not remove filter paper, fix (paper will come off on its own) and 
the bone section will stick to the slide.  Another form of "tape" transfer.
If you try this transfer, do not use the antiroll device, and hold onto the
paper at bottom. Play around with this, it may work well for you. 

Have also use a freehand brush technic, a delicate touch is needed, and be sure
to surround the bones with OCT to have it go under an antiroll device OR grasp
the section with brush technic.  

Free sections sectioned with antiroll device were more compressed than
transferred (the section is held in place as it is cut) section.  But it is
possible.  The up side is that the Cryojane is used for other problem tissues, 
can be used to cut larger bones easily.  I guess it is cost effective IF
one needs to do large volumes of tissues in order to justify the price,
we found that true.  On the other hand, practice and patience,  and
in our case more fiddly dinking to get the section was needed.  

There are several publications on how to freeze the bone properly

Gayle Callis  

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