Abstract: This invention relates to a flotation immunoassay employing a novel buoyant matrix to which an antigen or antibody is coupled and which separates the bound and free products of the assay by floating to the surface of the reaction liquid. The novel flotation device which makes it possible to detect and to quantitate either antigen or antibody can also be used to fractionate cells and molecules.

Abstract: This invention provides a method for detecting a target nucleic acid which comprises forming a reaction mixture which includes the target nucleic acid and an amount of a complementary single-stranded nucleic acid probe which is greater than the target molecule, under conditions which allow the probe and the target nucleic acid to hybridize to each other and form a double stranded target-probe complex, nicking the hybridized probe at least once within a predetermined sequence so as to form at least two probe fragments hybridized to the target nucleic acid, resulting in the probe fragments to become single-stranded and allowing the target nucleic acid to become hybridized to another probe; and identifying probe fragments, thereby detecting the target nucleic acid. This invention also provides a method for detecting a target nucleic acid.

Abstract: The invention relates to DNA encoding a functional serotonin 5HT1c receptor, e.g., cDNA, and to the isolated, functional serotonin 5HT1c receptor encoded by such DNA. The invention also relates to mammalian cells expressing the cDNA encoding the 5HT1c receptor and to a DNA probe useful for detecting nucleic acid encoding the serotonin 5HT1c receptor. This invention provides methods for determining binding to the serotonin 5HT1c receptor, methods of detecting the expression, and the presence of the serotonin 5HT1c receptor on the surface of a cell and to a method of screening drugs to identify drugs which specifically interact with, and bind to the serotonin 5HT1c receptor on the surface of a cell.

Abstract: An interspecific antigen of Mycobacteria consists essentially of a mixture in substantially immunochemically pure form of a protein having a molecular weight of at least about 4.times.10.sup.6 Daltons and polysaccharide having a molecular weight of at least about 1.times.10.sup.6 Daltons, and has when subjected to cross-electrophoresis an immunoelectrophoretic precipitation pattern corresponding to A60-antigen of Mycobacteria bovis strain BCG. This antigen is effective for detecting the prior exposure of a subject to Mycobacterial infections by a cutaneous test.

Abstract: An immunoassay method for one-step detection of specific antibodies which includes incubation of a solid phase support or matrix having a spot of the antigen bound thereto with a sample of the clinical fluid to be tested in the presence of a signal developing reagent, including a detector substance, which is preferably a colloidal metal sol, and a ligand, such as protein A or other antibody binding ligand. A diagnostic field kit containing the test antigens and signal developing reagent is also described.

Abstract: Methods are disclosed for detecting an antigen in a biological sample. The methods involve providing in combination a solid support, which is substantially free of specific binding proteins, and a medium comprising an antigen from the sample and an antibody for the antigen. The combination is incubated under conditions sufficient for the antibody when bound to the antigen to bind to the support. The presence or amount of antibody on the support or in the medium is determined and is related to the presence of antigen in the sample. The methods have particular application to the detection of gram-negative bacteria.

Abstract: The present invention relates to a method of diagnosis of pathological pregnancy which relies on an evaluation of the amount of placental isoferritin (PLF) in the serum or amniotic fluid of a pregnant woman. Diagnosis may also be achieved by observation of percentages of PLF-bearing lymphocytes in the pregnant female. Detection of PLF levels is achieved by immunoassay with a PLF-specific anitbody. Also described is a method of treating or preventing pathological pregnancies and transplant or graft rejection by administration of effective amounts of PLF and/or a PLF-specific antibody in combination with immunization.

Abstract: A method of performing a diagnostic immunoassay utilizing colloidal non-metal particles having conjugated thereto a binding component capable of specifically recognizing an analyte to be determined. After reaction of the sample and colloidal non-metal particles, the presence or amount of analyte/colloidal non-metal particle complexes are determined by optical analysis as a measure of the amount of analyte in the sample. The method can be utilized for the specific detection of numerous analytes and is sensitive and has a wide detection range.

Abstract: A method for preparing selected peptide substrates for detecting the activity of virus-specified proteases is provided. Specific tetrapeptide substrates are disclosed which are conjugates of protease-cleavable indicator groups and peptide sequences resembling picornavirus protease cleavage recognition sites.

Abstract: A chemiluminescence process comprising the contacting of a chemiluminescence precursor, an oxidant, an enzyme, a chemiluminescence enhancer and a nitrogen compound selected from the group consisting of ammonia and water-soluble organic amines. The reaction of such process can be used in detection of nucleic acid hybrids, antibodies, antigens and peroxidase enzymes and in producing light.

Abstract: Estrane and androstane derivatives of formula I ##STR1## wherein X is bromine, iodine, triphenyltin or trialkyltin of 1 to 6 carbon atoms per alkyl radical,Y represents two hydrogen atoms or methylene,Z represents two hydrogen atoms, oxo or alkylenedioxy of 2 to 6 carbon atoms andV is ethylene, vinylene, 1,3-propylene or cyclopropylene,R.sub.1 is hydrogen or a hydrocarbon radical of up to 8 hydrocarbon atoms, optionally interrupted by an oxa group or substituted by an oxo group,R.sub.2 is methyl or ethyl,R.sub.3 and R.sub.4 represent a carbon-carbon bond or R.sub.3 is hydrogen and R.sub.4 is hydrogen or methyl,.DELTA.symbolizes a 4(5)-double bond if Z signifies two hydrogen atoms or an oxo group; or a 5(6)-double bond or, for the estrane derivatives of formula I, also a 5(10)-double bond, if Z is alkylenedioxy,are pharmacologically effective substances or intermediates for preparation thereof.

Abstract: An immunochemical assay to determine the presence or concentration of antigen or antibodies in a fluid, comprising: (a) forming a ternary complex of a first labelled antibody or antigen, a second labelled antibody or antigen, and the antigen or antibody to be determined; and (b) detecting a signal produced in the presence of at least one substrate, by an interaction between said first label and said second label, enhanced by their proximity to each other bound to the antigenic substance.

Abstract: A sac, in particular a vesicle, having a detectable metal, in particular a rear earth metal, encapsulated therein. The sac may be sensitized with a ligand and used in an assay. The vesicle is stored and/or used in an aqueous solution which includes the rare earth metal to increase the concentration of metal in the sac.

Abstract: Neoplastic and other diseases can be diagnosed by assaying a human test sample e.g. body fluid, tissue or cultured tumor explant cells, for structurally altered or abnormally expressed growth factor receptors or for the RNA transcripts of genes which encode them. For example, the assay can be for truncated EGF receptor having at least a portion of its mature amino terminus deleted. Antibodies, capable of binding a predetermined amino acid sequence within the EGF receptor, are also useful in diagnosis and therapy as are conjugates of an immunogenic polymer bound to a polypeptide fragment of EGF receptor. DNA and RNA encoding EGF receptor or fragments thereof are also described.

Abstract: Contrast medium compositions for delineation of bowel during magnetic resonance imaging (MRI) of the abdomen are provided for oral or rectal administration. The compositions consist of aqueous suspensions of clay in finely-divided particles which expose a large surface area to the suspending water and impose a condition of dynamic anisotropy upon the adjacent water, resulting in reduction predominantly in the transverse relaxation time of the water and subsequent loss of signal from the bowel lumen.

Abstract: A new marker for colorectal carcinoma has been discovered which is a glycoprotein having a molecular weight of approximately 160,000 daltons. Assay methods which can identify this marker are useful indetecting, diagnosing, and monitoring colorectal carcinoma, and in particular, carcinoma of the undifferentiated variety which heretofor were not readily detectible. For example, an assay which utilizes an antibody reacting to this glycoprotein marker is useful in a screening method for the detection and monitoring of colorectal carcinoma cells. Such an antibody can be included as part of a kit for screening a patient for colorectal carcinoma.

Abstract: A flow through test device and assay kit suitable for use by unskilled technicians is described. The flow through device has a porous support and an absorptive layer. The device is constructed for control of flow rates so that a tracer having a visible particulate label can be used. Optional flow control and porous spacer layers may be included.

Abstract: Microcapsules labeled with an antigen or antibody contain a liquid containing a fluorescent substance, for example, carboxyfluorescein. The liquid in the microcapsules is prepared so as to have a viscosity different from that of a liquid outside the microcapsules. For example, the microcapsules contain polyvinyl alcohol as a substance for increasing the viscosity. Antigen-antibody reaction is caused by mixing such microcapsules, a sample and a complement, and complement is activated with resulting antigen-antibody complex, whereby the microcapsules are lysed.The reaction mixture is irradiated with exciting light, and the polarization components (I.sub..parallel. and I.sub..perp.) of fluorescence from the reaction mixture are detected. The concentration of a substance to be assayed in the sample is determined by calculating the degree of polarization fluorescence P on the basis of the intensities of the polarization components.

Abstract: The invention relates to new quinoline derivatives of the formula: ##STR1## wherein R stands for C.sub.2 H.sub.5, C.sub.2 H.sub.4 F, CH.sub.2 -O-CH.sub.2 -CH.sub.2 OH, ##STR2## to a process for their preparation comprising reacting, for 12-24 hours, at 70.degree.-95.degree. C., in dimethylformamide, the 1,4-dihydro- 3-ethoxycarbonyl- 6,8- difluoro-4-oxo-quinoline with an excess of RX (2-5 mol of RX for one mol of quinoline), in the presence of K.sub.2 CO.sub.3 and subsequently hydrolysing the obtained 3-ester by HCl under reflux conditions and to pharmaceutical compositions comprising at least one 1,4-dihydro- 3-carboxy- 6,8-difluoro- 1-R-4-oxo-quinoline derivative in admixture with a pharmaceutically acceptable diluent or carrier.

Abstract: The present invention relates to enzyme immunoassays employing one or more enzyme label-substrate pairs which give rise to colored products and in which absorption by the product of substrate conversion by at least one enzyme label at a first wavelength, at or close to the optimum wavelength for absorbance, exceeds the linear range of the detector, which immunoassay includes the steps of measuring the said substrate conversion at a second wavelength at which absorbance by the relevant product is significantly lower than at the said first wavelength and calculating the true absorbance at the said first wavelength by utilizing the result of linear regression analysis of absorbance measurements obtained with product standards at the said first and second wavelengths within the linear range of the detector.