[Histonet] formalin neutralization
For those who are better at chemistry than I am: I have just purchased some Formalex Green to neutralize our waste 10% formalin for safe drain disposal. I noticed that I can also purchase a "test kit" that will tell me if the aldehydes are safely neutralized. Instead of that, couldn't I just add a drop of Schiff's reagent to the final product, and that would indicate if there are any unreacted aldehydes? Thank you in advance, Stephanie Weaver Texas Veterinary Diagnostic Lab ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
[Histonet] Re: horseshoe crabs
I have no experience with horseshoe crabs, but we do process many aquatic animal specimens. We have used Davidson's fixative (acetic-alcohol-formalin) to soften the exoskeleton. Post-fixation after 10% NBF works as well, since many of our clients do not have anything but formalin on hand. I'm not sure how well it would work on something as large and solid as a horseshoe crab, but we have had success with fish, shrimp, and hermit crabs. Stephanie Weaver Texas Veterinary Medical Diagnostic Laboratory Message: 10 Date: Thu, 28 May 2009 10:56:10 +0100 From: Deborah Faichney Subject: [Histonet] Horseshoe crab..help! To: "histonet@lists.utsouthwestern.edu" Message-ID: <8ed3f2ca5b78e142b8193376c57330f8e198e18...@exch2007.ad.stir.ac.uk> Content-Type: text/plain; charset="us-ascii" Hi all, I have a Masters student here who has Horseshoe crab tissues fixed in 10% NBF. Most of the tissues have been sectioned successfully but the eyes are surrounded by armour plated chitin! (she broke two Dremel drills trying to cut the carapace and finally tin snips had to be used to cut them out!!). Any thoughts on how to soften them? Looking around on the Net, I have found that processing and clearing through Chloroform may soften, also a solution called Diaphanol has been recommended. At the moment they have been two days in a 1 part acetic acid to 5 parts NBF with no effect. We only have a couple of weeks to do this work so cannot adopt any trial or lengthy methods. Is this possible? I like a challenge, but suspect this needs a miracle. Its no wonder these beasties have been on the planet for so long. Many thanks Debbie Faichney Histopathology Institute of Aquaculture University of Stirling Stirling, FK7 7QS Scotland Uk ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
[Histonet] IHC stainer
I am in a veterinary diagnostic lab. In the past we have had very few requests for IHC and have always sent slides out to another lab to perform IHC as needed. It is time for us to start doing our own and join the modern age. We have several certified technicians, but none have experience with IHC and we typically have a relatively high turnover rate. Therefore, I am hoping to be able to buy an automated stainer. In the past most people on the list seemed to be very happy with the Dako autostainer, but this past week has brought so many bad remarks about Dako's service that I am reconsidering. We probably will not need a high capacity autostainer, but I would like walk-away capability with an easy to use system. It will need to accept other companies reagents, since veterinary infectious disease antibodies aren't often sold by the major companies. Also, cost is an issue and I would like to be able to bargain shop for reagents through other companies. Does anyone have any recommendations, or warnings as to what to avoid? In a related issue, where do other animal tissue people get their antibodies for infectious diseases, e.g. Parvovirus, canine distemper, or FIP? Thanks for the advice! Stephanie Weaver Texas Veterinary Medical Diagnostic Lab ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
histonet@lists.utsouthwestern.edu
Dear Histoland, I have a dilemma that I was hoping you could help me puzzle out. I am in a veterinary diagnostic lab. I have been asked to improve our H&E stain to produce "more contrast between the blues and reds". They would especially like for mast cell granules to "pop out" in an H&E stain so that we have fewer requests for special stains. Here is our current protocol, using a linear stainer with each station set at 1 minute so that 4 stations equals 4 minutes: 1. Dry slides in forced air slide dryer at 70 C, 20 minutes 2. Xylene, 5 minutes 3. Absolute alcohol, 2 minutes 4. 95% alcohol, 1 minute 5. distilled water, 1 minute 6. Gill 3 hematoxylin from Anapath, 3 minutes 7. Running tap water, 1 minute 8. 20% glacial acetic acid in 80% reagent alcohol, 1 minute 9. Running tap water, 2 minutes 10. 80% reagent alcohol, 1 minute 11. Alcoholic Eosin Y from Anapath, 2 minutes 12. 95% reagent alcohol, 1 minute 13. Absolute alcohol, 2 minutes 14. Xylene, 3 minutes Our tap water is alkaline enough to blue the slides adequately, but I do intend to insert a Scott's tap water as a bluing reagent to improve day-to-day consistency. I have tried several changes already, including: -increase the time in hematoxylin -increase the time in eosin -variations of acid-alcohol (10% acetic acid in 80% alcohol, 10% acetic acid in 95% alcohol, and 20% acetic acid in 95% alcohol) -add Scott's tap water substitute for bluing -mix and match all of the above So far the favorite is our current protocol but replacing the acid alcohol with the 20% acetic acid in 95% alcohol, but some pathologists find this "too blue" and others are still not seeing mast cells distinctly enough. Please send any and all suggestions for I have just about run out. Thank you for your help and expertise! Stephanie Weaver Diagnostic Lab Supervisor--Histopathology 979-845-3414 swea...@tvmdl.tamu.edu ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
