Dear C.Jones,
    I think this may be caused by microtomy techniques. Are your techs
soaking the blocks in warm water (floating the blocks on the water bath),
briefly cooling, the block and then taking the sections? If so, I seem to
remember a posting on the histonet (help me here fellow netters) that stated
this type of soaking will result in poor nuclear staining. The heating of
the tissue with warn water some how changes the ability of the nuclei to
bind hematoxylin.
    Try using an ice slush to facilitate improved microtomy. Face the block
then immerse in the ice slush for a few minutes.
I have used this technique for years and have never had staining problems.
Good Luck!

Pat Haley
Histotechnologies, inc
www.histology.net

 ----- Original Message -----
From: <CJones6672@aol.com>
To: <histonet@pathology.swmed.edu>
Sent: Sunday, August 20, 2000 6:01 PM
Subject: processor artifacts in tissue


> My Histology Lab is currently using a Leica tissue processor and have
> encountered some severe processing problems.  The stained slides have
nuclear
> "ghosting" and   a washed out appearance. The problem appears to be
reagent
> carry over as it usually starts occurring about 2 to 3 runs after all of
the
> reagents are changed. We have had the machine serviced and checked
numerous
> time without solving the problem.
> Has anyone else encountered this problem with their Leica? I would like to
> hear from anyone with suggestions or comments.
> C Jones
> Emory Cartersville Medical Center
>
>