Abstract: Methods and compositions are provided for coating a substrate with a strongly adherent hydroxyapatite coating, which allows for ingrowth of natural bone and strong bonding between the coating and the substrate. The procedure provides for repetitive coatings at varying concentrations of coating forming reagents, where the highest concentration is used initially. The coating has particular application for prostheses, where porous areas of the prostheses are completely coated with a thin sturdy coating of hydroxyapatite.
Abstract: An electrophoretic system is provided which allows for carrying out electrophoresis while monitoring and regulating the temperature and the electrical field gradient in the gel. In addition, photometric monitoring, including use of an optical stage, is provided so as to monitor the progress of the electrophoretic separation and vary conditions to change the progress as desired. A computer is employed which receives the signals from the electrophoretic and photometric apparatuses and regulates temperature and voltage to either maintain conditions, or change the conditions to vary the progress of the electrophoresis and to store the separation results. A sample applicator and a sample retriever are also provided, to provide even and consistent application of sample to the gel and to allow recovery of portions of the sample without destroying or removing pieces from the gel.
Abstract: Nucleated fetal cells such as nucleated fetal red blood cells are separated from maternal blood with a discontinuous triple gradient gel and centrifugation. Nucleated fetal red blood cells are collected at an interface between a gel layer having a density in the range of from 1.105 to 1.110 g/mL and the second layer having a density in the range of from 1.075 to 1.085 g/mL, and maternal granulocytes are collected at an interface between a gel layer having a density in the range of from 1.115 to 1.125 g/mL and a layer having a density in the range of from 1.105 to 1.110 g/mL. This allows separation of fetal cells for testing from the maternal blood rather than the placenta or amniotic fluid, reducing the risk of sample collection and facilitating routine testing of fetal cells for evidence of genetic defects.
Type:
Grant
Filed:
September 25, 1992
Date of Patent:
January 4, 1994
Assignee:
The Board of Trustees of the Leland Stanford Junior University
Inventors:
Nelson N. H. Teng, Neelima M. Bhat, Marcia M. Bieber
Abstract: The invention provides for methods and compositions to detect the presence of anti-HLA antibodies, HLA antigen or preformed HLA-containing immune complexes in biological samples. The complement protein Clq is bound to a solid substrate, then mixed with a biological sample containing immune complexes. The immune complexes are preformed, or formed by adding HLA antigens to a biological sample containing antibodies to HLA, or alternatively, by combining a biological sample containing HLA antigens with defined antibodies to HLA. The immune complexes bind to Clq, and are then detected by the addition of a labeled reagent.
Abstract: Apparatus and methods are provided for the detection of analytes. A polyunsaturated polymerized lipid layer is employed, which is anisotropic, has a member of a specific binding pair bound to an end of the lipids, and whose optical characteristics are modified upon complex formation between the specific binding pair member and its complementary member. By providing for polarized light, linear and/or circular, one can detect the presence of complex formation by the change in the optical characteristics of the film. Polarizers, analyzers, and wave plates are employed for providing for a light signal which can be analyzed and related to the presence of an analyte in a sample.
Type:
Grant
Filed:
December 13, 1990
Date of Patent:
December 7, 1993
Assignee:
Biocircuits Corporation
Inventors:
Hans O. Ribi, Todd A. Guion, Joseph R. Murdoch, John C. Scott, Victor Pan, Glenda L. Choate
Abstract: Non-instrumented assays are providing employing a flow-path with a moveable sample receiving pad, which moves from a sample receiving site to a bridging site between a transport element and a measurement region. A reagent transport solution is employed which comprises enzymes capable of reacting with the analyte to produce hydrogen peroxide, where horseradish peroxidase may catalyze a reaction resulting in the formation of a detectable boundary in the measurement region. The distance of the boundary is indicative of the amount of analyte in a sample.
Abstract: A self-contained assay device is provided, where an analyte may be detected or be quantitated by measuring the distance of a detectable signal from a predetermined site. The device employs two strips separated by a gap, where a flow path is completed by movement of a sample receiving pad into the gap. The movement of the sample receiving pad also results in release of a reagent solution which is then transported through the pad into the quantitation area where the amount of analyte may be determined. Various chemistries may be employed for providing a detectable signal.
Type:
Grant
Filed:
July 2, 1991
Date of Patent:
November 9, 1993
Inventors:
Urs A. Ramel, Michael P. Allen, Prithipal Singh
Abstract: Reactivity between alloantigen and alloantigen-specific ligand, such as HLA and anti-HLA antibody, is detectable in a sample by separating from the sample a portion of a targeted class of ligands (including such ligands complexed with alloantigen) and measuring the amount of alloantigen in such complex containing fractions. In another embodiment of the invention, reactivity between a plurality of samples is detected by measuring soluble alloantigen in at least first and second biological samples and in a mixture of the samples. Since the formation of alloantigen immune-complexes in the mixture alters the physical and immunological behavior of soluble alloantigen, a divergence between the measured and expected concentration of the mixture indicates reactivity.
Abstract: Physiological samples are typed for HLA-B27 by contacting the sample with an antibody which binds to HLA-B7 and is not cross-reactive between HLA-B7 and B27, separating the sample from any complexes which are formed, and then testing the sample for the presence of HLA-B27 with an antibody which is cross-reactive for HLA-B7 and B27 in a STAT test. Particularly, an enzyme conjugate is used which binds to a membrane allowing for the detection of any HLA-B27 bound to the membrane.
Abstract: Methods are provided for the production of large polypeptides containing repeating sequences of amino acids utilizing biochemical techniques, specifically DNA sequences coding for the expression of the large polypeptides. Systems utilizing exogenous transcriptional and translational regions to control the production of the large polypeptides are also provided.
Type:
Grant
Filed:
October 29, 1987
Date of Patent:
September 7, 1993
Assignee:
Protein Polymer Technologies, Inc.
Inventors:
Franco A. Ferrari, Charles Richardson, James Chambers, Stuart C. Causey, Thomas J. Pollock, Joseph Capello, John W. Crissman
Abstract: Recombinant structural and functional polymers are purified by lysing of the cellular host, separation of the solid materials, washing and extraction of contaminants using a detergent solution at elevated temperatures.
Type:
Grant
Filed:
April 13, 1992
Date of Patent:
August 10, 1993
Assignee:
Protein Polymer Technologies, Inc.
Inventors:
Joseph Cappello, Franco A. Ferrari, Tina L. Buerkle, Garret Textor
Abstract: Mineralized collagen is prepared by forming calcium phosphate mineral under mild agitation in situ in the presence of dispersed collagen fibrils. A stable composition is obtained with desirable physical characteristics mimicking the characteristics of bone.
Type:
Grant
Filed:
February 26, 1992
Date of Patent:
July 27, 1993
Assignee:
Norian Corporation
Inventors:
Brent R. Constantz, Subramanian Gunasekaran
Abstract: Soluble HLA cross-matches are determined by providing for antibodies or ligand bound to a solid substrate specific for at least one HLA allele and detecting complexes between either donor or recipient HLA antigens and recipient or donor antibodies, respectively, or reference HLA and patient antibodies, particularly IgG antibodies. Conveniently, anti-human immunoglobulin (Ig), particularly human IgG, conjugates are employed where the anti-human Ig is conjugated with a label capable of providing a detectable signal to permit detection of human anti-HLA bound to said solid substrate.
Abstract: Novel methods and novel industrial Bacillus strains are provided for enhanced production of serine protease. Plasmid constructs comprising the serine protease gene are introduced into a compatible host, generally a Bacillus already overproducing serine protease. Preferred host cells are those from Bacillus novo sp. PB92 and the preferred serine protease gene also originates from Bacillus PB92. Integration and maintenance of the plasmid in the host cell chromosome can be achieved by including a temperature sensitive origin of replication in the plasmid construct and growing under selective conditions.
Type:
Grant
Filed:
February 29, 1988
Date of Patent:
June 8, 1993
Assignee:
Gist-Brocades, NV
Inventors:
Christiaan A. G. van Eekelen, Johannes C. van der Laan, Leo J. S. M. Mulleners
Abstract: A sample applicator/retriever for gel electrophoresis is provided, which allows easy and reproducible application or retrieval of samples. The sample nozzle is designed to load samples uniformly through a gel. The applicator/retriever may be in several different forms, including a a multiwell device, individual wells and mounting bar, a single line well, or a concentrator applicator.
Type:
Grant
Filed:
September 30, 1992
Date of Patent:
June 8, 1993
Assignee:
Labintelligence, Inc.
Inventors:
Erich Gombocz, Mark Dwight, David H. Rammler
Abstract: High density lipoprotein-cholesterol determination is made employing a device which allows for removal of red blood cells, measurement of sample volume, removal of LDL and VLDL, and quantitation of HDL-cholesterol on a quantitation strip.
Type:
Grant
Filed:
November 21, 1990
Date of Patent:
June 1, 1993
Inventors:
P. Jivan Patel, Michael P. Allen, Prithipal Singh
Abstract: Improved self-contained automated assay devices are provided which allow for reliable release of eluent solution upon opening of a pouch with scoring teeth, so that the solution is transferred to a well for carrying out the assay. The improvements comprise using a bibulous member which is moved into the pouch to initiate eluent solution transport or providing for a sudden shock to the solution to initiate flow.
Abstract: A luminescence measuring system is provided for detecting luminescence at extremely low concentrations of luminescing moieties. The method employs alternating radiation at a plurality of loci of an inhomogenous solution, where the radiant power is maintained constant, and the irradiated volumes of pairs of loci are systematically varied. With the probability being very low that the same luminescence signal will be obtained in the two or more measurements, by comparing the measurements, one can detect a low luminescence signal in the presence of relatively high noise levels. Various techniques are described for modulating the irradiance and detecting changes in signal.
Type:
Grant
Filed:
June 5, 1991
Date of Patent:
March 2, 1993
Assignee:
Acrogen, Inc.
Inventors:
Fritz S. Allen, Carlos Bustamante, Thomas M. Niemczyk, Burton P. Dorman
Abstract: Methods, compositions and apparatus are provided for coating a substrate with a strongly adherent hydroxyapatite coating, which allows for ingrowth of natural bone and strong bonding between the coating and the substrate. The procedure provides for coating under conditions which form sticky particles which bind to the substrate to form a crystalline hydroxyapatite coating. The coating has particular application for prostheses, where porous areas of the prostheses are completely coated with a thin sturdy coating of hydroxyapatite.The apparatus includes a coating trough in which the substrates are present and the reactive components added. The medium is recirculated in an outer circuit through a distribution tank solution preparation tank and coating trough. Means are provided for maintaining temperature and pH. The substrates are maintained in a line normal to the flow in the trough and can be rotated to ensure even coating.
Abstract: Novel compositions are provided for the production of hydroxyapatite, where a dry mixture is provided which combines a calcium source and an acidic phosphate source, particularly monocalcium phosphate monohydrate or orthophosphoric acid crystals. These two are combined, optionally with other ingredients, with mechanical mixing, resulting in partial reaction or intimate combination to produce a product which requires less water for formation of a desired viscosity, has enhanced mechanical properties and is physiologically acceptable.
Type:
Grant
Filed:
July 2, 1991
Date of Patent:
January 12, 1993
Assignee:
Norian Corporation
Inventors:
Brent R. Constantz, Bryan Barr, Kevin McVicker