Dear Petty,
 Thanks for your input.  I will pass along any answers to the question of
gms/pas stains that come my way.

LeRoy Brown HT(ASCP) HTL
Histology Consultation Services
P.O. Box 1109
85 SE 8th Ave.
Oak Harbor, WA 98277
****
1-360-675-9173
fax 1-360-675-5820
web site  www.histocs.com

----- Original Message -----
From: "Lee & Peggy Wenk" <lpwenk@mail.netquest.com>
To: "LEROY BROWN" <lhbhcs@pioneernet.net>
Sent: Friday, March 16, 2001 12:56 PM
Subject: Re: re:gms/pas


> Hmmm. Interesting concept. Never tried it or thought about it before.
>
> Let's try to think through some theory and logic.
>
> In the GMS, the silver attaches to aldehydes that you created on the
> fungus via the periodic acid or chromic acid, thus staining the fungus
> black.
>
> On the PAS, the Schiff attaches to the aldehydes that you created on
> the fungus via periodic acid, staining the fungus magenta.
>
> It seems that, if you attach the silver to the aldehydes first, there
> wouldn't be
> any aldehydes left for the Schiff to attach to. And the same with first
> attaching
> the Schiffs and then trying to attach the silver - no leftover aldehydes
for
> the second stain.
>
> However, there are could be enough aldehydes on the fungus that
> didn't pick up the first chemical, so would be available to pick up
> the second chemical. But black-magenta fungus? Isn't that overkill?
>
> Just theorizing, I could possibly see a use for this in trying to stain
> fungus
> and Pneumocystis carinii (PC) on the same section. In that case, stain
> with PAS first (which would demonstrate the fungus, but NOT the PC).
> Then, without going into chromic acid or periodic acid a second time
> (don't need to oxidize the fungus as you already did that with the PAS),
> go into the methenamine silver to demonstrate the PC.
>
> I'd love to hear if anyone does this, why, and how it looks. Always
> looking for new things to learn.
>
> Peggy A. Wenk, HTL(ASCP)
> William Beaumont Hospital
> Royal Oak, MI
>
>
>
> ----- Original Message -----
> From: "LEROY BROWN" <lhbhcs@pioneernet.net>
> To: "histonet" <histonet@pathology.swmed.edu>
> Sent: Friday, March 16, 2001 12:57 PM
> Subject: re:gms/pas
>
>
> > Dear Histonet,
> >
> > Does anyone have a method for doing a combination gms/pas stain for
> paraffin
> > sections?
> >
> > Thanks
> >
> > LeRoy Brown HT(ASCP) HTL
> > Histology Consultation Services
> > P.O. Box 1109
> > 85 SE 8th Ave.
> > Oak Harbor, WA 98277
> > ****
> > 1-360-675-9173
> > fax 1-360-675-5820
> > web site  www.histocs.com
> >
> >
> >
> >
>
>