On Fri, 18 May 2001, Tony Henwood wrote:
> The best thing to do is run your existing technique in parallel with the
> modified using aqueous picric acid. Use mirror sections, possibly kidney,
> liver, tongue and intestine, and compare the results. Record in the lab's
> development notebook and that should satisfy the accreditors.

Tony H is quite right. That's what you should do.

> A few days ago there was a discussion about use of Bouins and John
> Kiernan sent a post saying that it was not necessary to use Bouins 
> (for the Masson  Trichrome) when a Sat aqueous picric acid solution 
> works just as well. Is this documented somewhere? If I change the 
> written procedure I'd like to include a reference.

I have compared Bouin with Picric-alone in the context of trichrome
staining but have not published anything about it. This was part of
a study (still incomplete) of the AZAN method. It will get submitted
to a journal as a few lines in some longer paper in the next year
or two, and will be published if the referees say it's OK. Until
then, my word is just a "personal communication" (= worthless).
Your words, if you follow Tony Henwood's advice, will amount to
a proper record of a controlled comparison of pre-treatments.

Masson's name is attached to several methods that use dyes that are
different (in chemistry and colour) from those originally prescribed 
by Masson himself (who was a pathologist in Montreal and wrote a
great big book about tumours). The major difference between Masson
and its variants and the technically simpler Mallory method is the 
prior staining of nuclei with an iron-haematoxylin. With Mallory and 
AZAN the nuclei are stained by the same red dye that colours cytoplasm.

----------------------------------------
John A. Kiernan
Department of Anatomy & Cell Biology
The University of Western Ontario
London,  Canada   N6A 5C1
   kiernan@uwo.ca
   http://publish.uwo.ca/~jkiernan