Abstract: An immunoassay utilizing a novel liposome composition in which there is incorporated a stabilizing or destabilizing component and an antigen. The presence of cognate antibodies in test samples is detected by the alteration of the supramolecular structure of the liposomes resulting in changes in stabilization. Destabilization can be detected, and in certain cases, caused by, the addition of magnesium or calcium ions. Increased stabilization can be detected by the polymerization of bilayer components in response to ultraviolet light. Antibody-antigen interactions at the liposome surface mediate the stabilization/destabilization response.

Abstract: A method to determine the Gram sign of microorganisms includes staining the microorganisms with a plurality of fluorescent dyes, applying excitation energy to the stained microorganisms, and observing the color of the fluorescence emission of the stained microorganisms. Gram-positive and Gram-negative microorganisms stain different colors, and assignment of the Gram sign may be made on the basis of the color of the stained microorganisms.

Abstract: A method for the early diagnosis of Bordetella diseases based on the detection of Bordetella adenylate cyclase and the ability of this enzyme to catalyze the formation of cyclic adenosine monophosphate (cAMP). A sample secretion is taken from a suspected victim of a Bordetella disease (the most common of which in humans is whooping cough) and incubated under conditions to promote the formation of cAMP, which may then be measured as evidence of the presence of the disease. A sample of nasopharyngeal secretions is maintained in a nutrient medium pending assay. An adenylate cyclase assay is made by incubating the sample with adenosine triphosphate (ATP) and the calcium binding protein calmodulin to generate cAMP. The cAMP is measured by any of several known available methods.

Abstract: Improved hybridization probe compositions and method for detecting nucleic acids are provided. A hybridization probe constructed to contain thionucleotides is hybridized to a nucleotide sequence of interest in the absence of formamide, DTT and dextran sulfate. If a cold (.sup.32 S) thionucleotide is incorporated into the probe molecule, the probe is provided with a detectable label, radioactive or otherwise.

Abstract: A fluorine resin membrane is made hydrophilic to a prescribed depth in the direction of thickness thereof to produce an asymmetrical membrane having a hydrophilic portion and a hydrophobic portion. An enzyme is immobilized in the hydrophilic portion of the membrane to obtain a membrane having a function of enzymatic reaction and a function of selective gas permeation. The hydrophilic portion is formed by causing a perfluoroalkyl surface active agent to penetrate the prescribed depth that is to be hydrophilic.

Abstract: This invention relates to a process for producing immobilized L-asparaginase preparations. Its principal object is to produce immobilized L-asparaginase preparations which are excellent in antithrombogenicity and mechanical strength.The present invention is concerned with production of immobilized L-asparaginase preparations by pouring an aqueous solution containing 6% or more of a polyvinyl alcohol with a degree of hydrolysis of 97 mol. % or higher and a viscosity-average degree of polymerization of 1,800 or more an antileukemic asparaginase into a vessel or a mold of an appropriate shape, subjecting the solution to cooling, solidification and molding at a temperature of -15.degree. C. or lower and partially dehydrating the molded mass without thawing to a dehydration ratio of 5% by weight or more and, if desired, immersing the product in water.According to the invention, L-asparaginase can be embedded in a highly hydrous gel excellent in antithrombogenicity and mechanical strength by simple procedures.

Abstract: Hybridomas which produce human monoclonal antibodies are disclosed. The hybridomas are formed by fusing lymphocytes from individuals with various cancers to an immortal cell line, such as a myeloma, from, e.g., a human cell line, or a mouse cell line.

Abstract: A carrier for immobilization of physiologically active substances is prepared by treating an assembly of regenerated cellulose fibers having a single fiber fineness of from 0.5 to 30 deniers and a length of at least 1 millimeter with a solution of a polymer having an acid anhydride group. This carrier is easy to handle and permits immobilization of a large amount of a physiologically active substance. Thus it can be used as a catalyst for chemical reactions, a specific absorbent for separation and purification, a material for clinical examination, or a medical material.

Abstract: Type O erythrocytes are produced from certain subtypes of A erythrocytes or type AB erythrocytes by contacting the same following equilibration of a pH of 5.6-5.8 with an .alpha.-N-acetylgalactosaminidase, preferably obtained from an avian liver, for periods sufficient to convert the A antigen in the erythrocyte to the H antigen. Following removal of the enzyme, the erythrocyte is re-equilibrated to a pH of 7.2-7.4. As a result, there is obtained O type erythrocytes characterized by a 60 to 90 percent ATP level based on the level of ATP in naturally occurring O or AB erythrocytes. Beginning with certain A cells one obtains synthetic O erythrocytes characterized by a terminal .alpha.-fucose moiety, O antigenicity, and the absence of A antigenicity. Beginning with A.sub.2 B erythrocytes, one obtains B erythrocytes by the same process characterized by the absence of A antigenicity, greater H antigenicity than naturally occurring A.sub.2 B cells, the presence of B antigenicity and the aforedescribed ATP levels.

Abstract: A biochemical process for optical resolution of 4-hydroxy-3-methyl-2-2'-propynyl-2-cyclopentenone, which comprises asymmetrically hydrolyzing organic carboxylic acid (saturated or unsaturated carboxylic acids having 1 to 18 carbon atoms) esters of (.+-.)-4-hydroxy-3-methyl-2-2'-propynyl-2-cyclopentenone by the action of an esterase originated from a microorganism or an animal pancreas to give optically active 4-hydroxy-3-methyl-2-2'-propynyl-2-cyclopentenone and esters of its antipode with high optical purity is disclosed. This resolution process is simple in steps as compared with the conventionally known organic chemical methods of optical resolution, and is quite advantageous industrially because it does not require expensive optically active reagents.

Abstract: S-adenosyl-L-homocysteine is produced by contacting adenosine with D-homocysteine in an aqueous medium in the presence of cells or treated cells of a microorganism of the genus Pseudomonas having the ability to racemize D-homocysteine to DL-homocysteine and in the presence of S-adenosyl-L-homocysteine hydrolase, to synthesize S-adenosyl-L-homocysteine, and thereafter collecting it.

Abstract: Biocatalysts in bead form which contain microorganisms are particularly advantageously obtained by radical polymerization of acrylamide with methylene-bis-acrylamide in aqueous-organic phase suspension when the organic phase is a highly fluorinated carbon compound. The biocatalysts thus obtained have high stability and activity and are suitable for biotechnical processes.

Abstract: A method of resolving racemic 2-halopropionic acids by lipase-catalyzed asymmetric esterification in an organic medium is disclosed.

Abstract: A microdroplet test apparatus for use in HLA typing. The apparatus is an improvement upon the well known Terasaki tray which is in use for determining HLA antigens by measuring lymphocyte cytotoxicity. The apparatus includes a tray having a plurality of microtest wells wherein the sides of the microtest wells are designed to promote localization of lymphocytes or other cells being tested at the microtest well bottom. The apparatus further includes a cover having either rods or tubes which extend down into the test solution present in the microtest well to thereby control the amount of test solution which is present in the cylindrical optical view path through which the test solution is viewed by microscope for test result measurements.

Abstract: A diagnostic aid for use in detecting occult blood in faeces is described. The aid consists of a carrier which is coated with specific monoclonal anti-human antibody and, which upon contact with a faecal liquid suspension, specifically absorbs human hemoglobin. A chemical or an enzymatic assay may then be used to detect the hemoglobin.

Abstract: An assay for detecting SLE antibodies utilizing a novel liposome composition in which there is entrapped a divalent cation responsive indicator. The presence of such antibodies is detected by their stabilization of the supermolecular structure of the liposomes. Such stabilization can be detected, and in certain cases, caused by, the addition of magnesium or calcium ions.

Abstract: A process for preparing L-aspartic acid by contacting fumarate ion-containing solution with aspartase or aspartase-producing microorganisms, adding maleic acid to insolubilize or precipitate the L-aspartic acid, isomerizing maleic acid in the supernatant liquid to form fumaric acid and recycling the fumaric acid into contact with the enzyme or microorganisms.

Abstract: A suspension of particles such as carboxylated polystyrene latex particles are coated (as by carbodiimide coupling) with an antigen (such as chemically modified Bovine Serum Albumin). The antigen-coated particles are incubated with a gamma-globulin to the antigen (such as can be produced by immunizing rabbits) under non-agglutinating conditions. The particles having antigen/gamma-globulin immune complexes are recovered and resuspended to form a diagnostic reagent which agglutinates when mixed with human serum containing Rheumatoid Factor.

Abstract: This disclosure relates to a class of compounds which are utilized as biological stains in fluorescent microscopy. In particular, the disclosure relates to a method for detecting and identifying various structures in a biological sample which comprises treating said biological sample with a compound of the present disclosure to form a complex which emits fluorescence when irradiated with incident light. This class of compounds has been shown to be useful in detecting a variety of structures such as, for example, viruses, bacteria, yeasts, fungi, reticulocytes and cells in biological samples.