Dear Histonetters,
  I am asking these questions for a co-worker.

What is the best method for slide preparation of frozen tissue sections
that will be fixed and used for FISH (Fluorescence In Situ Hybridization).
Are positively charged slides best? Should slides be air dried after
cutting before fixation in 4% paraformaldehyde? Can the fixed slides be
stored dehydrated at  -20 degrees C or at room temperature? Should they be
heated (what temp & time) before beginning the pretreatment steps? 
She recently had trouble with tissue adherence after digestion and
hybridization when using frozen tissue, a problem she doesn't have with
formalin fixed,paraffin embedded tissue. 
Any other tips will be greatly appreciated. Thanks again for your time and
input.

Lynn McKee
University of Cincinnati