[Histonet] Problems with mouse brains

[kemlo]

Agree, poor formalin fixation will allow nuclear bubbling which some
authorities put down to the effects of heat on the sub optimally stabilised
proteins. What a marvellous phrase "your formol is not well tamponated".
Wish I had thought of that......

I will of course steal it if you allow such plagiarism? 

-----Original Message-----
From: histonet-bounces <@t> lists.utsouthwestern.edu
[mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Ana Resendes
Sent: 04 April 2009 15:16
To: Randolph-Habecker, Julie
Cc: histonet <@t> lists.utsouthwestern.edu
Subject: Re: [Histonet] Problems with mouse brains

have very light H&E staining: first you should check if either your eosin or
haematoxilin are over used


nuclear bubbling: can be a lot of things but can be inclusion.
Brain sections are big so make at least a 24 h inclusion process.

and extensive tissue cracking: could be over heating or bad inclusion. You
have to check if reagents in inclusors are ok or over passed, I would change
all reagents.

I also have noticed some formalin pigment: your formol is not well
tamponated


2009/4/3 Randolph-Habecker, Julie <jhabecke <@t> fhcrc.org>

> Folks,
>
> I need some input on a problem we're seeing with some mouse brain
> samples. The samples are from new born mice P0 to P14 which have been
> fixed in 10% NBF (Fisher brand and well within expiration date) for 72
> hours. They are then transferred to 70% etoh and processed on an 8 hour
> process. After the tissue is embedded, we are taking sagital sections,
> drying them overnight, and then baking overnight at 60C. They are then
> stained with H&E. This has been working great but now all of a sudden we
> have very light H&E staining, nuclear bubbling, and extensive tissue
> cracking. I also have noticed some formalin pigment.
>
> My first thought is that there was difference in formalin or time in
> formalin but that is not the case. I also wondered if the tissue might
> be exposed to excessive heat. We checked all of the temperatures in our
> processor, embedding center, and water baths - all were within
> tolerance.
>
> Any ideas what might cause all three artifacts? Could it be from
> inadequate paraffin infiltration?
>
> Any help would be greatly appreciated!
>
> Thanks,
>
> Julie
>
> Julie Randolph-Habecker, Ph.D.
> Staff Scientist - Director
> Experimental Histopathology Shared Resource
> Fred Hutchinson Cancer Research Center
> 1100 Fairview Ave, N. DE-360 (Please note new location)
> Seattle WA 98109-1024
> 206-667-6119
> jhabecke <@t> fhcrc.org
>
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>



-- 
Ana Resendes
DVM, MSc, PhD
Veterinary pathologist
Centro de Investigação de Recursos Naturais (CIRN)
Secção de Anatomia e Taxonomia Zoológicas, Departamento de Biologia,
Universidade dos Açores.
Rua da Mãe de Deus, 58 - Apartado 1422
P - 9501-801 Ponta Delgada (Açores)
Portugal
Tel. (+351)  296 650 000 ext. 1109
Fax  (+351) 296 650 100
http://www.uac.pt/~pherg/
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