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US4145185A Expired / Lapsed US ⏱️ 0.0 years remaining

Reagents for screening tests and bioassay of von Willebrand's factor (platelet aggregating factor) in blood plasmas

Assignee: RTI International
•
Filing: 1977-02-25
•
Granted: 1979-03-20
•
Expires: 1997-02-25
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Abstract

Abstract Screening tests and bioassay of von Willebrand's factor (platelet aggregating factor) in human and animal blood plasma are effected using a reagent of blood platelets and snake venom having a positive platelet aggregating cofactor effect. The reagent and tests may also suitably employ dried blood platelets. The reagent may comprise dried platelets and either ristocetin or active snake venom as the platelet aggregating cofactor.

Inventors

  • 👤 Kenneth M. Brinkhous
  • 👤 Marjorie S. Read

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:05
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/5005

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 34 words
A test reagent for the bioassay of von Willebrand's factor and platelet aggregating factor in blood plasmas comprising blood platelets and a snake venom characterized as having a positive cofactor effect for platelet aggregation.
Claim 2
Dependent Claim 34 words
A test reagent for the bioassay of von Willebrand's factor and platelet aggregating factor in blood plasmas comprising blood platelets and a snake venom characterized as having a positive cofactor effect for platelet aggregation.
Claim 3
Dependent Claim 35 words
The test reagent of claim 1 wherein said venom is obtained from a snake selected from the species Bothrops jararaca, Bothrops alternatus, Bothrops neowiidis, Trimeresurus flavoviridis, A. rhodostoma, Bothrops atrox, Bothrops jararacussu, and Bothrops lansbergii.
Claim 4
Dependent Claim 23 words
The test reagent of claim 2 wherein said species is selected from Bothrops jararaca, Bothrops alternatus, Bothrops neowiidis, Trimeresurus flavoviridis, and A. rhodostoma.
Claim 5
Dependent Claim 19 words
The test reagent of claim 2 wherein said species is selected from Bothrops jararaca, Bothrops alternatus, and Bothrops neowiidis.
Claim 6
Dependent Claim 13 words
The test reagent of claim 1 wherein said venom is Bothrops jararaca venom.
Claim 7
Dependent Claim 11 words
The test reagent of claim 1 wherein said platelets are fixed.
Claim 8
Dependent Claim 11 words
The test reagent of claim 6 wherein said platelets are dried.
Claim 9
Dependent Claim 42 words
A test reagent for the bioassay of von Willebrand's factor and platelet aggregating factor in human and animal plasmas comprising fixed-dried blood platelets and, as a cofactor for platelet aggregation, a snake venom characterized as having a positive cofactor effect, or ristocetin.
Claim 10
Dependent Claim 42 words
A test reagent for the bioassay of von Willebrand's factor and platelet aggregating factor in human and animal plasmas comprising fixed-dried blood platelets and, as a cofactor for platelet aggregation, a snake venom characterized as having a positive cofactor effect, or ristocetin.
Claim 11
Dependent Claim 11 words
The test reagent of claim 8 wherein said platelets are airdried.
Claim 12
Dependent Claim 11 words
The test reagent of claim 8 wherein said platelets are lyophilized.
Claim 13
Dependent Claim 38 words
A procedure for the bioassay of von Willebrand's factor in blood plasma which comprises determining the rate of aggregation of a platelet suspension effected by adding human or animal blood plasma to the test reagent of claim 1.
Claim 14
Dependent Claim 35 words
A procedure for the bioassay of von Willebrand's factor in blood plasma which comprises determining the rate of aggregation of a platelet suspension effected by adding blood plasma to the test reagent of claim 8.
Claim 15
Dependent Claim 54 words
In a method of determining the degree of platelet aggregation in blood plasma wherein a suspension of blood platelets and a cofactor for platelet aggregation are a dded to the plasma to be tested, the improvement which comprises using snake venom characterized as having a positive cofactor effect as a cofactor for platelet aggregation.
Claim 16
Dependent Claim 54 words
In a method of determining the degree of platelet aggregation in blood plasma wherein a suspension of blood platelets and a cofactor for platelet aggregation are a dded to the plasma to be tested, the improvement which comprises using snake venom characterized as having a positive cofactor effect as a cofactor for platelet aggregation.
Claim 17
Dependent Claim 50 words
In a method of determining the degree of platelet aggregation in human and animal plasma wherein a suspension of blood platelets and a positive cofactor for platelet aggregation are added to the plasma to be tested, the improvement which comprises using blood platelets which have been air dried or lyophilized.
Claim 18
Dependent Claim 50 words
In a method of determining the degree of platelet aggregation in human and animal plasma wherein a suspension of blood platelets and a positive cofactor for platelet aggregation are added to the plasma to be tested, the improvement which comprises using blood platelets which have been air dried or lyophilized.
Claim 19
Dependent Claim 47 words
A procedure for the bioassay of von Willebrand's factor in blood plasma which comprises determining the rate of aggregation of a platelet suspension by adding to human or animal blood plasma blood platelets and a snake venom characterized as having a positive cofactor effect for platelet aggregation.
Claim 20
Dependent Claim 47 words
A procedure for the bioassay of von Willebrand's factor in blood plasma which comprises determining the rate of aggregation of a platelet suspension by adding to human or animal blood plasma blood platelets and a snake venom characterized as having a positive cofactor effect for platelet aggregation.

References Cited (Backward Citations)

SU338221A1 Cited
US3869548A Cited
US3714345A Cited
US3715427A Cited
US3761586A Cited
US3987159A Cited
US3819605A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-03-19 1982-09-18 1983-03-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-03-19 1986-09-18 1987-03-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-03-19 1990-09-18 1991-03-20 $7700.00 Window Closed / Lapsed

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