INTRAOPERATIVE DIAGNOSTIC TECHNIQUE FOR THYROID CARCINOMA Russian patent published in 2014 - IPC G01N33/52 

FIELD: medicine.

SUBSTANCE: tumour tissue sample and visually intact adjoining tissue sample are cut out from an intraoperatively extracted involved lobe of the thyroid gland; the tissue samples are homogenised in a buffer containing 50 mM Tris-HCl (pH 7.5), 100 mM NaCl, 1 mM EDTA, 1 mM dithiothreitol, 1 mM ATP, 10 mM Na₂S₂O₅ in a relation of the tissue weight, mg to the buffer amount, mcl, of 1:6; the prepared homogenates are centrifuged for at least 5 sec to prepare supernatants of the tissue samples containing proteasomes of the tumour tissue or proteasomes of the visually intact adjoining tissue. Each supernatant in an amount of 2, 4 and 6 mcl is placed in a solution 100 mcl containing 30 mcM fluorogenic substrate Suc-LLVY-AMC of chymotrypsin-like centres of proteasomes and 20 mM Tris-HCl (pH 7.5), 1 mM dithiothreitol, 5 mM MgCl₂, 1 mM ATP; that is followed by a hydrolysis reaction of Suc-LLVY-AMC with proteasomes at 37°C for at least 5 min; 250 mcl of 1.4% SDS is added to terminate the hydrolysis reaction. The chymotrypsin-like activity of proteasomes is shown by a fluorescence intensity of the hydrolysed substrate in fluorimeter units. If the fluorescence intensity of the hydrolysed substrate in the tumour tissue sample exceeds the fluorescence intensity of the hydrolysed substrate in the visually intact adjoining tissue by at least 3 times, thyroid carcinoma is diagnosed.

EFFECT: higher accuracy and reduced time for intraoperative diagnosis of thyroid carcinoma for selecting an adequate extent of operation.

6 cl, 3 tbl, 2 ex