Definition:
The Diastase-Periodic Acid Schiff (PAS) method is a histochemical staining technique used to detect glycogen and other polysaccharides in tissue samples. Diastase is an enzyme that digests glycogen, and the PAS stain highlights polysaccharides by producing a magenta color.
Phonetic Pronunciation:
(dye-uh-stays PEER-ee-ah-dik AS-id shif)
Etymological Origin:
The term "diastase" comes from the Greek word "diastasis," meaning "separation," referring to the enzyme's ability to break down glycogen. "Periodic acid" is named for its periodic structure, and "Schiff" refers to Hugo Schiff, the chemist who developed the Schiff reagent used in the staining process.
Significance in Asbestos Context:
The Diastase-PAS method is significant in the context of asbestos-related diseases because it helps differentiate between mesothelioma and other cancers, such as adenocarcinoma. In mesothelioma, the PAS stain is typically negative after diastase digestion, whereas adenocarcinomas often retain PAS-positive staining. This distinction is critical for accurate diagnosis and subsequent legal or medical actions related to asbestos exposure.
Synonyms or Related Terms:
Example Sentence:
"The Diastase-Periodic Acid Schiff (PAS) method was used to confirm the diagnosis of mesothelioma in the patient with a history of asbestos exposure."
Common Misconceptions:
