Yuck. 

> ----------
> From: 	Simon Smith[SMTP:ssmith@skeletech.com]
> Sent: 	Thursday, April 27, 2000 11:42 AM
> To: 	'Molinari, Betsy'
> Subject: 	RE: WHERE ARE THE CO2 MICROTOMES?
> 
> I mean throwing away anything!  One of my most influential mentors in
> the UK
> would empty the coffee pot dregs back into the water receptacle, top
> up with
> water, fill with coffee and brew a new pot.  Tasted vile, but it gave
> him
> enough of a caffeine jolt to get him moving...
> 
> -----Original Message-----
> From: Molinari, Betsy [mailto:BMolinari@heart.thi.tmc.edu]
> Sent: Thursday, April 27, 2000 4:03 AM
> To: histonet
> Subject: RE: WHERE ARE THE CO2 MICROTOMES?
> 
> 
> Do you mean throw away specimens or equipment?
> 
> > ----------
> > From: 	Simon Smith[SMTP:ssmith@skeletech.com]
> > Sent: 	Wednesday, April 26, 2000 11:15 AM
> > To: 	Histonet (E-mail)
> > Subject: 	RE: WHERE ARE THE CO2 MICROTOMES?
> > 
> > We had two of them when I worked at the London Hospital back in
> > Blighty.  We
> > found both of them in dumpsters when the anatomy department had a
> > clear out.
> > 
> > 
> > We used one of them once to cut serial 100um sections of unfixed
> human
> > cartilage and subchondral bone.  To do this we clamped it to a shelf
> > in the
> > walk in -20 freezer, let the temperature equilibrate, then removed
> it
> > when
> > the thing siezed solid to replace the lubricant with low temperature
> > lube.
> > 
> > Once set up it worked pretty well, you put on your skiing gear, go
> in,
> > cut a
> > few sections, come out, warm up, go back in.
> > 
> > I wonder where it is now?  I would guess either in the dumpster or
> > where we
> > left it surrounded by a group of puzzled biochemists wondering what
> > the hell
> > it is.
> > 
> > I have another semi off-topic question; do histologists ever throw
> > anything
> > away?  I have noticed this inability to part with anything in the
> > majority
> > of the histologists I respect.
> > 
> > Regards
> > 
> > Simon
> > 
> > Simon Smith B.Sc. AIBMS
> > Supervisor, Laboratory Resources
> > Skeletech, Inc.
> > 22002 26th Ave SE, Suite 104
> > Bothell   WA   98021
> > Voice: (425) 424 2663   Fax:  (425) 424 2600
> > E-mail: ssmith@skeletech.com  
> > 
> > -----Original Message-----
> > From: J. A. Kiernan [mailto:jkiernan@julian.uwo.ca]
> > Sent: Wednesday, April 26, 2000 7:37 AM
> > To: Paulo Faria
> > Cc: Histonet
> > Subject: Re: WHERE ARE THE CO2 MICROTOMES?
> > 
> > 
> > On Tue, 25 Apr 2000, Paulo Faria wrote:
> > 
> > > ... Where are the old CO2 microtomes?  I thought 
> > > that before cryostats were readily available they were popular. Is
> > that 
> > > true? Where are they? 
> > 
> >  One of them, made by Leitz, is in my lab. It's at least 40 years
> old,
> >  has served me well for the last 27, and is still in regular use. 
> > 
> >  Opinion: For getting thick sections of formaldehyde-fixed organs
> (and
> >    I mean FIXED, at least overnight and preferably for a week), you
> > can't
> >    beat a CO2 freezer. Unless you're supremely skilful you can't get
> >    serial sections; for this you need accessories that maintain the 
> >    temperature of the chuck, either by circulating cold alcohol
> > through
> >    its innards or by using a Peltier-effect device (which needs
> >    circulating tap water to carry the heat away from its "hot" 
> >    thermocouple junctions).
> > 
> >    A pathologist examining a frozen section from this traditional
> >    instrument must be able to evaluate sections very much thicker
> than
> >    the 4 to 7 um of routine paraffin histology. The screw advance
> >    on a typical CO2 freezer is calibrated from 0 to 100 um, and you 
> >    can waggle the handle (moving the blade) to do double or treble
> >    increments of thickness, but unless you can make use of
> occasional
> >    lucky scraps don't expect anything thinner than about 20 um. A
> >    freezing microtome is at its best with sections that are
> nominally
> >    40 to 80 um thick. The real thickness is variable, as is obvious
> >    at a glance to anyone who uses one. 
> >  
> >    Cryostats offer many advantages over the freezing microtome:
> > thinner
> >    sections; fixation is optional, etc etc.  There are nevertheless
> >    plenty of circumstances when thicker sections are more
> informative
> >    than thin ones. It isn't easy to cut an 80 um section of
> anything,
> >    fixed or unfixed, in a cryostat. 
> > 
> >    Another good thing about freezing with carbon dioxide is that
> >    it's fast, and ice crystal holes are rarely visible in the
> >    sections.
> > 
> >  Perhaps some will disagree about these perceived virtues of the
> >  CO2 freezing microtome!
> > 
> >  John A. Kiernan,
> >  Department of Anatomy & Cell Biology,
> >  The University of Western Ontario,
> >  LONDON,  Canada  N6A 5C1
> > 
> > 
> > 
>