After you have developed a processing protocol and obtained good infiltration after a certain time (hours) in paraffin, any and all the time above that period of adequate infiltration = exposure to prolonged heat. Some histotechs even don't fill the holding chamber in the embedding center, a practice I do not think is adequate. To your second question, just place them in NBF and when fixed filter and wrap them yourself while cassetting, do not wrap them before being fixed. René J.
--- On Mon, 10/5/09, Nancy Schmitt <nancy_schm...@pa-ucl.com> wrote: From: Nancy Schmitt <nancy_schm...@pa-ucl.com> Subject: [Histonet] time in paraffin and fried bloody specimen To: "Histonet (histonet@lists.utsouthwestern.edu)" <histonet@lists.utsouthwestern.edu> Date: Monday, October 5, 2009, 11:06 AM Good Morning Histonetters- First question: Textbook says "tissue should remain in paraffin the shortest time necessary for good infiltration because exposure to prolonged heat causes shrinkage and hardening". Can anyone define "exposure to prolonged heat"? Is that an hour? Three hours? Sitting in the paraffin waiting to be drained. I would appreciate some insight on this. Second question: Endom, POC tissue, even some sinus contents arrive wrapped in lens paper. These bloody specimens are fried (for lack of a better word) and almost impossible to separate from the lens paper. Is there something different we or the PA can be doing differently or just the nature of the tissue. Thanks for your help! Nancy NOTICE: This email may contain legally privileged information. The information is for the use of only the intended recipient(s) even if addressed incorrectly. If you are not the intended recipient, please notify the sender that you have received it in error and then delete it along with any attachments. Thank you. _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet