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Patent US4258131A successfully refreshed from Google Patents.
US4258131A
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US
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Method of fractional quantitative determination of isoenzyme of lactic dehydrogenase
Assignee: Oriental Yeast Co Ltd
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Filing: 1979-07-03
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Granted: 1981-03-24
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Expires: 1999-07-03
Abstract
Abstract 1,6-Dihydro nicotinamide adenine dinucleotide inhibits both H-type lactic dehydrogenase and M-type lactic dehydrogenase which are isoenzymes of lactic dehydrogenase, but the degree of inhibition thereof against H-type considerably differs from that against M-type. A ratio of H-type lactic dehydrogenase to M-type lactic dehydrogenase in serum can be measured by utilizing the difference of inhibition degree. Therefore we can diagnose the organ with trouble.
Inventors
- 👤 Isamu Takagahara
- 👤 Juniti Yamauti
- 👤 Setsuko Yoshimura
- 👤 Katsumi Fujii
- 👤 Takekazu Horio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:09
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
209 words
A method for the fractional quantitative determination of H-type and M-type lactic dehydrogenase in a biological sample comprising: reacting a portion of said biological sample with an aqueous solution containing pyruvate and a mixture containing 1,6-DHNAD and NADH at a rate of 1,6-DHNAD/NADH varying from 1/500 to 1/20, meanwhile reacting a second portion of said biological sample with an aqueous solution containing pyruvate and NADH, determining the ratio between lactic dehydrogenase activity obtained under the coexistent conditions of 1,6-DHNAD and NADH and lactic dehydrogenase activity obtained under non-coexistent conditions thereof, using the relationship P=(P.sub.H -P.sub.M)R.sub.H +P.sub.M wherein R H equals the ratio of H-type LDH activity to total LDH activity when 1,6-DHNAD is absent; P H equals the ratio of H-type LDH activity when 1,6-DHNAD is present, to the H-type LDH activity when 1,6-DHNAD is absent; P M equals the ratio of M-type LDH activity when 1,6-DHNAD is present, to the M-type LDH activity when 1,6-DHNAD is absent; and P is the ratio of total LDH activity when 1,6-DHNAD is present, to the total activity when 1,6-DHNAD is absent; and comparing said ratio with a standard value of which the inhibitory degree of isoenzyme has been previously found whereby the amount of isoenzyme in the sample is fractionally obtained.
Claim 2
Independent Claim
209 words
A method for the fractional quantitative determination of H-type and M-type lactic dehydrogenase in a biological sample comprising: reacting a portion of said biological sample with an aqueous solution containing pyruvate and a mixture containing 1,6-DHNAD and NADH at a rate of 1,6-DHNAD/NADH varying from 1/500 to 1/20, meanwhile reacting a second portion of said biological sample with an aqueous solution containing pyruvate and NADH, determining the ratio between lactic dehydrogenase activity obtained under the coexistent conditions of 1,6-DHNAD and NADH and lactic dehydrogenase activity obtained under non-coexistent conditions thereof, using the relationship P=(P.sub.H -P.sub.M)R.sub.H +P.sub.M wherein R H equals the ratio of H-type LDH activity to total LDH activity when 1,6-DHNAD is absent; P H equals the ratio of H-type LDH activity when 1,6-DHNAD is present, to the H-type LDH activity when 1,6-DHNAD is absent; P M equals the ratio of M-type LDH activity when 1,6-DHNAD is present, to the M-type LDH activity when 1,6-DHNAD is absent; and P is the ratio of total LDH activity when 1,6-DHNAD is present, to the total activity when 1,6-DHNAD is absent; and comparing said ratio with a standard value of which the inhibitory degree of isoenzyme has been previously found whereby the amount of isoenzyme in the sample is fractionally obtained.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |