Patent US4848349A successfully refreshed from Google Patents.
US4848349A
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Substance and method for measuring hepatic blood flow
Assignee: Individual
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Filing: 1987-04-29
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Granted: 1989-07-18
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Expires: 2007-04-29
Abstract
Abstract The invention discloses a new class of compounds, namely fluorescently labelled bile acids, as well as processes for their production. These compounds may be used for diagonistic and research purposes in humans and animals. The fluorescently labelled bile acids may be used: to indirectly measure hepatic blood flow; to measure gastrointestinal absorption of bile acids or salts; for the localization of nodules in tissues which absorb bile acids; and for the in vitro and in-vivo analysis of cellular or microcirculatory transport or other phenomena.
Inventors
- 👤 Igor A. Sherman
- 👤 Murray M. Fisher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:55
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/001; A61K49/0013; A61K49/0017; A61K49/005; A61K49/0052; A61K49/0019; A61K49/0021; A61K49/0041; A61K49/0043
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
21 words
A diagnostic procedure for humans and animals comprising the use of fluorescently labelled bile acid to indirectly measure hepatic blood flow.
Claim 2
Dependent Claim
21 words
A diagnostic procedure for humans and animals comprising the use of fluorescently labelled bile acid to indirectly measure hepatic blood flow.
Claim 3
Dependent Claim
37 words
The diagnostic procedure of claim 1 comprising the steps of: (a) introducing the fluorescently labelled bile acid into the blood stream; and (b) thereafter measuriang the elimination rate of the fluorescently labelled bile acid from the blood.
Claim 4
Dependent Claim
49 words
The diagnostic procedure of claim 1 comprising the steps of: (a) introducing the fluorescently labelled bile acid into the blood stream at a constant rate for a period of time required to achieve steady state; and (b) thereafter measuring the steady state concentration of the fluorescently labelled bile acid.
Claim 5
Dependent Claim
67 words
The diagnostic procedure of claim 2 wherein: (a) the human or animal is given a single IV bolus injection of fluorescently labelled bile acid; (b) serial blood samples are taken at intervals following the bolus injection and the concentration of fluorescently labelled bile acid therein is determined; and (c) hepatic blood flow is calculated from the rate of change in blood concentration of fluorescently labelled bile acid.
Claim 6
Dependent Claim
75 words
The diagnostic procedure of claim 4 wherein hepatic blood flow is calculated using the formulae: ##EQU7## where Q L is nutritional liver blood flow; M is the amount of fluorescently labelled bile acid injected; K is a constant dependant on the rate of extraction; c(t) is the monoexponentially declining concentration of injected fluorescently labelled bile acid in the blood; Q p is plasma clearance of the fluorescently labelled bile acid; and Htc is blood hematocrit.
Claim 7
Dependent Claim
134 words
The diagnostic procedure of claim 3 wherein: (a) the fluorescently labelled bile acid is introduced by continuous infusion at a constant rate; (b) the plasma concentration of the fluorescently labelled bile acid is measured from a blood sample taken after steady state equilibrium is reached; (c) hepatic plasma clearance is calculated using the formula: ##EQU8## where m o is the rate of infusion of the fluorescently labelled bile acid in μmole/sec; C p is plasma concentration of the fluorescently labelled bile acid in μmoles/cc; k is a constant equal to the hepatic extraction ratio of the fluorescently labelled bile acid; and Q p is plasma clearance of the fluorescently labelled bile acid; (d) hepatic blood flow is calculated using the formula: ##EQU9## where Q L is hepatic blood flow and Htc is blood hematocrit.
Claim 8
Dependent Claim
18 words
The diagnostic procedure of claim 5 or 6 wherein the fluorescently labelled bile acid is fluorescein isothiocyanate-bile acid.
Claim 9
Dependent Claim
31 words
A research procedure for human and animal studies comprising the use of a compound containing fluorescently labelled bile acid for the in-vivo analysis of cellular or microcirculatory transport or other phenomena.
Claim 10
Dependent Claim
31 words
A research procedure for human and animal studies comprising the use of a compound containing fluorescently labelled bile acid for the in-vivo analysis of cellular or microcirculatory transport or other phenomena.
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) | 1992-07-17 | 1993-01-16 | 1993-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-17 | 1997-01-16 | 1997-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-17 | 2001-01-16 | 2001-07-18 | $7700.00 | Window Closed / Lapsed |