John Kiernan asks: > > >>Bob, Why weren't they routinely buffering (or at least neutralizing) the > formalin fixatives at Johns Hopkins as recently as 1970? - It had all been > in the scholarly books (by Pearse, Lillie, etc) for >10 years, and was also > in Lee Luna's 1968 Manual of Histologic Staining Methods, published by the > USA's Armed Forces Institute of Pathology.<< >
Quite so, but the tyrannical (and seriously dyslexic) chief histotechnologist did not permit any sort of buffering, not even the then-venerable (and quite ineffective) chips of marble (calcium carbonate) in the bottom of the bottle. Ralph Lillie's book (which I still have, along with the AFIP manual) failed to specify sodium phosphate dibasic anhydrous (Na2HPO4) in the formula, though Lee Luna did. Unfortunately, the heptahydrate salt (which is nearly half water) was also available, and since it was the cheapest product in the catalog, people usually ordered it, and I suppose that's what the guy at JHH had done. - If you made up Lillie's formula using the heptahydrate salt, without doubling the quantity you added, you got a pH of 6.1. In my travels I saw several times that a lab would make up the pH 6.1 buffer, then laboriously titrate in NaOH solution to bring the pH up to 7, using a pH meter. A time or two I recalculated the formula for the heptahydrate for them (in other words, multiplying by 1.9) and fixed the problem. He also didn't permit procedure manuals, requiring techs to memorize the special stains, the result being that most of them scribbled out procedures and hid them in their desk drawers. When I was near the end of my residency and wanted to take some of the methods with me, I'd laboriously assemble the procedure by borrowing those reference cards, which usually contained a lot of incorrect information. (One result of that was that I was the only person who preserved the Johns Hopkins eosin Y - phloxine B - Biebrich scarlet formula for the fabled JHH eosin stain, whose intensity very nearly seared the microscopist's eyeballs.) The senior pathologists tolerated all of this because they didn't know enough about what went on in the laboratory to take any corrective action. Pathologists trained then, and I guess now, thought that slides just sorta fell out of the sky. It was a valuable learning experience for me. I learned the importance of the pathologist knowing how to do almost everything in the histology lab. I think this experience ought to be part of every anatomic pathologist's training. Bob Richmond Maryville TN _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet