On Sun, 1 Jul 2001, Tibor Ric wrote:

> Recently our fine neadle prostate biopsies were starting falling of the
> glases....It may be as simple as too short time on 65 temperature celsius
> but I would like to hear what do You think, what could be the reason of
> falling of....

I've not worked with needle biopsies, but have dried many 
other cells, sections, smears, squashes, dissected specimens
etc onto slides at various temperatures. 65C is too hot, IMHO, 
for anything other than bacteria. When something dries too 
quickly on a flat surface the edges (thinnest part) curl upwards, 
leaving an unduly small central area to adhere. This happens
when you fry bacon: water (and fat) are lost first at the
edges of the rasher, which curl up, leaving the centre
sticking (coagulant fixation) to the pan. 

With suspended cells the best adhesion and structural 
preservation are obtained when the unfixed cells stick
to the glass while wet. A Cytospin centrifuge does the 
sticking very quickly and effectively. (There may be
other makes that are just as good or better; Cytospin is the
only one I've used.) 

For squashed, smudged or otherwise splurged bits of tissue, 
drying at room temperature for about half an hour is often OK.
The preparation should be fixed when it looks as if it's
almost dry. A traditionally prepared blood film dries adequately 
in a few minutes, but it's rather special, with its own 
preservative medium (plasma) protecting the cells and providing 
physical properties amenable to stretching out on glass to 
give a thin layer.

The title line for this enquiry is about Van Gieson's stain.
Is this used for needle biopsies of the prostate? It's a
wonderful technique (easier to do than H & E and more
informative in displaying tissue structure), but can it 
really be the best one for identifying normal and abnormal
cell-types in a tiny biopsy?