US 9,809,837 B2
Method for evaluating suitability of duodenal fluid sample as sample for detecting pancreatic fluid-derived components
Masanori Asakura, Kawasaki (JP); Tomonori Nagaoka, Tokyo (JP); and Nao Shimada, Tokyo (JP)
Assigned to OLYMPUS CORPORATION, Tokyo (JP)
Filed by OLYMPUS CORPORATION, Tokyo (JP)
Filed on Dec. 19, 2016, as Appl. No. 15/382,996.
Application 15/382,996 is a continuation of application No. PCT/JP2015/055403, filed on Feb. 25, 2015.
Prior Publication US 2017/0096699 A1, Apr. 6, 2017
Int. Cl. C12Q 1/37 (2006.01); G01N 33/58 (2006.01)
CPC C12Q 1/37 (2013.01) [G01N 33/582 (2013.01); G01N 2333/96433 (2013.01); G01N 2333/96477 (2013.01)] 8 Claims
 
1. A method for evaluating a suitability of a duodenal fluid sample as a sample for detecting pancreatic fluid-derived components, comprising:
(a) mixing a duodenal fluid sample with a chymotrypsin-specific substrate and measuring an amount of degradation of the chymotrypsin-specific substrate by the duodenal fluid sample, the chymotrypsin-specific substrate having a cleavage site for chymotrypsin represented by the following general formula (1):
—(Y1) n1- (X1) -Pro - (Y2) n2-  (1)
wherein, Y1 and Y2 respectively and independently represent an amino acid residue or —CH2—NH—,X1 represents Phe, Trp or Tyr, and n1 and n2 respectively and independently represent an integer of 1to 10,
(b) mixing the duodenal fluid sample with a pepsin-specific substrate and measuring an amount of degradation of the pepsin-specific substrate by the duodenal fluid sample, the pepsin-specific substrate having a cleavage site for pepsin represented by the following general formula (2):
—(Y3)n3-Pro-(X2)—(Y4)n4-  (2)
wherein, Y3and Y4 respectively and independently represent an amino acid residue or—CH2—NH—,X2represents Phe, Trp or Tyr, and n3and n4respectively and independently represent an integer of 1to10, and
(c) evaluating that the duodenal fluid sample is suitable as a sample for detecting pancreatic fluid-derived components if the amount of degradation of the chymotrypsin-specific substrate by the duodenal fluid sample is higher than a first prescribed threshold and the amount of degradation of the pepsin-specific substrate by the duodenal fluid sample is lower than a second prescribed threshold, as being suitable as a sample for detecting pancreatic fluid-derived components.