Technology
An enhancement of immunoelectrophoresis in which a series of post-electrophoretic gel slabs are layered with cellulose-acetate gels saturated with specific antibodies. The resulting antigen-antibody complexes fixed on the second gel may then be stained, allowing sensitive and specific qualitative visual identification of paraproteins by electrophoretic position. It can be used to identify specific proteins in the blood or urine. It has greatest application in the identification and monitoring of monoclonal proteins that are produced in conditions like Waldenstom's macroglobulinaemia and multiple myeloma.
Diagnostic Methods
Technology
Immunohistochemical staining techniques allow for the visualization of antigens via the sequential application of a specific antibody to the antigen (primary antibody), a secondary antibody to the primary antibody and an enzyme complex with a chromogenic substrate. The enzymatic activation of the chromogen results in a visible reaction product at the antigen site. The specimen may then be counterstained and coverslipped. Results are interpreted using a light microscope and aid in the differential diagnosis of pathophysiological processes, which may or may not be associated with a particular antigen.
Diagnostic Methods
Technology
Laboratory test involving interaction of antigens with specific antibodies.
Diagnostic Methods
Technology
A high-resolution method used to isolate cells from their surrounding tissues, with the aid of a laser beam, under direct microscopic visualization. Specific cells can be isolated directly by cutting target cells away from unwanted cells, to obtain enriched cell populations.
Diagnostic Methods
Technology
A laboratory method in which the tissue from a histology slide is dissected under a microscope to procure specific cells or cell populations.
Diagnostic Methods
Technology
A technique that determines the nucleotide sequence of a pre-specified region of DNA or RNA by using primers that are specific for that region.
Diagnostic Methods
Technology
A serological test that measures the ability of antibodies in specific concentrations of serum to prevent the formation of plaques in a cell monolayer when combined with a viral suspension.
Diagnostic Methods
Technology
A method for amplifying a DNA base sequence using multiple rounds of heat denaturation of the DNA and annealing of oligonucleotide primers complementary to flanking regions in the presence of a heat-stable polymerase. This results in duplication of the targeted DNA region. Newly synthesized DNA strands can subsequently serve as additional templates for the same primer sequences, so that successive rounds of primer annealing, strand elongation, and dissociation produce rapid and highly specific amplification of the desired sequence. PCR also can be used to detect the existence of the defined sequence in a DNA sample.
Diagnostic Methods
Technology
Variation occurring within a species in the length of DNA fragments generated by a specific endonuclease. Such variations are generated by mutations that create or abolish recognition sites for these enzymes.
Diagnostic Methods
Technology
A technique for the detection of specific DNA fragments that have been separated by polyacrylamide-gel electrophoresis, transferred to a nitrocellulose or other type of paper or nylon membrane, and detected by hybridization and visualization with a labeled probe.
Diagnostic Methods
Technology
A novel karyotyping procedure which is based on the simultaneous hybridization of 24 chromosome-specific painting probes labeled with different fluorochromes or fluorochrome combinations. The measurement of defined emission spectra by means of interferometer-based spectral imaging allows for the definitive discernment of all human chromosomes in different colors. (from Schrock et al., Hum Genet 1997:101:255-62)
Diagnostic Methods
Technology
A procedure used to demonstrate nucleotide sequence variations that occur in the same region of DNA between individuals within a species, or between alleles in an individual to detect mutations in various genes, such as oncogenes, tumor suppressor genes, or genes responsible for genetic diseases. The method detects different conformations adopted by partially denatured DNA fragments resulting from their specific nucleotide sequences under denaturing conditions. Denatured single-stranded DNA fragments are allowed to partially renature without formation of double-stranded DNA. The particular conformations adopted by each of the renatured fragments depend on each of their specific nucleotide sequences. The fragments are run on polyacrylamide gels to detect subtle changes in migration due to their particular secondary structures. Resulting fragment band in the gel will misalign if any point mutations are present to alter the conformation.
Diagnostic Methods
