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PubMed1989

Radioimmunoassay of glycated serum protein using monoclonal antibody to glucitollysine and coomassie-brilliant-blue-coated polystyrene beads.

A radioimmunoassay for glycated serum protein (GSP) was developed using monoclonal antibody to glucitollysine and polystyrene beads coated with Coomassie-Brilliant-Blue (CBB) as adsorbent for serum protein. The monoclonal antibody was raised by immunizing BALB/c mice with reduced glycated LDL and fusing their spleen cells with mouse myeloma cells. CBB-coated polystyrene beads were introduced to absorb a constant amount of serum protein. The protein adsorbed on the CBB-coated beads was reduced by NaHB4, and after treatment with radiolabeled antibody, the radioactivity of each bead was counted with an automatic gamma-counter. The standard glycated protein used was reduced glycated human serum albumin, in which 8 of 59 lysine residues were glycated. The intra- and interassay coefficients of variation of GSP were 4.8-6.5% and 1.6-6.0%, respectively. The GSP level of diabetic patients was significantly higher than that of normal controls (1.97 +/- 1.23 vs. 0.47 +/- 0.21 nmol/mg-protein; mean +/- SD, p less than 0.001). The GSP levels of patients with insulin-dependent and non-insulin-dependent diabetes mellitus were 3.03 +/- 1.05 and 1.51 +/- 1.00 nmol/mg-protein, respectively. A good correlation was found between the levels of GSP and hemoglobin A1c (HbA1c) (r = 0.85, p less than 0.001). In patients admitted to the hospital for diabetes education and glycemic control, the GSP level decreased 43 +/- 12% with the decrease in the fasting plasma glucose level (39 +/- 13%) and the mean daily plasma glucose level (MPG, 47 +/- 15%) in a four week period after admission, whereas the HbA1c level decreased only 13 +/- 6% during this period.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

Target cell lysis by cytotoxic T lymphocytes redirected by antibody-coated polystyrene beads.

Cytotoxic T lymphocytes were found to mediate rapid lysis of target cells not normally recognized in the presence of small polystyrene beads coated with a combination of anti-T3 and antitarget cell antibodies. Lysis was not seen with beads bearing one of these antibodies alone, nor with a mixture of two types of beads each coated with a single antibody. The effector cells mediating this lysis include long term allospecific human CTL, and both human and mouse CTL clones recognizing mouse class I MHC Kb Ag. TNP-modified mouse tumor cells, a human lymphoblastoid line, and human red cells were found to be good targets for this cytotoxicity. Polystyrene beads with diameters of 3 to 15 mu caused target lysis, with a dose-response curve which typically went through a maximum and declined at high bead numbers. Maximal bead-redirected lysis by CTL was less efficient than that mediated by soluble antibody heteroconjugates of the same two antibodies. Bead-redirected target lysis was calcium dependent. These results are interpreted as a form of bystander lysis induced by the beads, since the target cell membrane is not directly crosslinked to the region of CTL activation. These observations thus favor a mechanism of lysis involving the polarized secretion of a locally acting lytic agent by CTL.

Antibodies↗

PubMed1988

[Comparative characterization of the polystyrene plates used in enzyme immunoassay].

The data on the comparison of the quality of polystyrene plates manufactured in the USSR with those manufactured by a number of foreign producers are presented. These data indicate that the capacity of antibodies adsorbed on a polystyrene plate for the sorption of antigens depend on the properties of the polymer surface and vary for different plates.

Immunoenzyme Techniques↗

PubMed1988

[Production of immobilized urease adsorbed on polystyrene granules].

We prepared adsorption immobilized Urease (E.C. 3.5.1.5) with a special method of polymer coating of polystyrene granulate as a matrix, and by subsequent adsorption of two different urease products (AWD Dresden, DDR, 3 U/mg, and Serva, Heidelberg, BRD, 41 U/mg). We obtained the strongest activity (4.0 mumol.g-1.min-1) with immobilisates on polystyrene in comparison with polyvinylchloride, and polyurethane layers, if we used AWD urease (PS, PVC, PUR). By using Serva urease we obtained products with a manyfold of activity (12.8 mumol.g.min-1). This high activity enables us to utilize adsorption immobilized urease for the detoxification of biological fluids.

Ammonia↗

PubMed1987

[Sorption properties of polystyrene plates used in immunoenzyme analyses].

The capacity of polystyrene carriers used in the enzyme immunoassay (EIA) for adsorbing 131I-labeled human serum albumin under different conditions has been studied, and the comparison of the plates manufactured by Dynatech AG (Switzerland) and by the Leningrad Works of Medical Polymers has been made. At the first stages of the reaction the antigen is separated from the carrier and the amount of the desorbed antigen depends on its initial dose and the dilution of the assayed sera. The irregular desorption of the antigen leads to misinterpretation of the results. Comparison of the polystyrene plates has shown that each plate is characterized by individual adsorption capacity, which impedes at present the standardization of EIA-based test systems.

Adsorption↗

PubMed1987

[Choice of the suitability criteria of polystyrene-based solid-phase carriers for performing immunoenzyme analyses].

The authors discuss a tentative approach to the choice of criteria indicating the optimal suitability of different solid-phase carriers made of polystyrene for use in the enzyme immunoassay (EIA), viz. the dependence of specificity, sensitivity, reproducibility and reliability of EIA results on the adsorption properties, transparency expressed in percent and transparency variations of the plates under test. The evaluation of the carriers by four parameters is proposed with the use of assay plates manufactured by Nunc A/S (Denmark) for control. To ensure the objective evaluation of the suitability of polystyrene plates for use in EIA, the choice of uniform criteria is necessary.

Adsorption↗

PubMed1987

Dual fluorometric/colorimetric detection system for an automated random-access instrument utilizing standard polystyrene test tubes as precision cuvettes.

To attain the optical precision necessary to precisely quantify fluorescent or colorimetric signals, analytical systems have typically included quality-controlled cuvettes, flow cells, or dual-beam reference systems. We describe a system where a fluorescence or transmittance signal is quantified in single, standard, 12-mm-diameter polystyrene test tubes. Tube-to-tube variation is minimized by referencing the primary signal to a second reference signal. The tube is carefully oriented within a positioner that allows for the precise placement of the tube within a light path 7.6 mm in diameter. The detection system allows for use of either four pairs of fluorescence excitation/emission wavelengths or eight transmittance wavelengths, which are selected by using specific interference filters. The impact of temperature, tube imperfections, surface flaws, and distortions is minimized by using a reference ratio. Fluorescence is measured with an orthogonal photomultiplier tube, and transmittance with a photodiode; both are illuminated with an ordinary long-life tungsten-halogen lamp. This system is used with the Becton Dickinson AFFINITY system, an automated random-access analyzer with analyte-specific unit-package reagents. The polystyrene tube of the reagent package, which has an antibody-absorbed surface, serves as both the cuvette and the separation medium. Use of the reference ratio method reduces intertube imprecision of fluorometric or transmittance signals, for more precise quantification of various analytes.

Autoanalysis↗

PubMedDate not supplied

[Biochemical properties of enterobacteria on polystyrene plates].

The authors studied 84 strains of enterobacteria. The reliability of the results of the biochemical testing obtained by the micromethod with the use of polystyrene plates was examined comparatively to the data obtained by the classical method and API microsystems manufactured in France. Of the 84 strains of enterobacteria, 36 belonged to Proteus, 24 to Enterobacter, 8 to Klebsiella, 5 to Citrobacter, and 11 to E. coli. Of the strains tested, 50 were isolated from the intestine of children and adults, 30 from the residual microflora of foods, and 4 were museum strains. Study according to 23 tests on the conventional media with consideration of the results after 18 to 48 hours demonstrated the coincidence of the data, obtained by the methods used, for most strains. This circumstance permits recommending the micromethod for testing the biochemical properties of enterobacteria on polystyrene plates for broad-scale use.

Bacteriological Techniques↗

PubMedDate not supplied

New FDA migration cell used to study migration of styrene from polystyrene into various solvents.

A new cell was evaluated for studying the migration of components of plastic food packaging materials into various food simulating solvents. Data obtained using this cell to study the migration of styrene from polystyrene at 40 and 70 degrees C are presented. Food simulating solvents tested were: water; 3% acetic acid; 8, 20, 50, and 100% ethanol; corn oil; HB-307; heptane; hexadecane; and decanol. An iterative Basic computer program is described that fits the migration vs time data obtained to mathematical models, based on Ficks' law, yielding migrant/polymer diffusion coefficients (Dp). Dp values determined for styrene migration from polystyrene at 40 and 70 degrees C were 3 X 10(-13) and 4 X 10(-12) sq. cm/s, respectively.

Chemical Phenomena↗

PubMed1985

Phagocytosis of polystyrene spheres in the rabbit corneal endothelium: contribution of lysosomal enzymes to the endothelial degeneration.

The rabbit corneal endothelium phagocytized polystyrene spheres 0.5 micron in diameter. After phagocytizing spheres, the endothelium degenerated, and lost from the Descemet's membrane. Lysosomal enzyme activities of the endothelium-Descemet's membrane complex, such as acid phosphatase, beta-glucuronidase and N-acetyl-beta-D-glucosaminidase, were assayed and the total activities per microgram DNA were almost constant. The unsedimentable activities in the complex, however, increased by phagocytosis of polystyrene spheres, which indicated an extralysosomal release of lysosomal enzymes. Released lysosomal enzymes probably would have accounted for the degeneration of the corneal endothelium.

Animals↗

PubMed1981

Deletion of antigen-specific activity from leukocyte dialysates containing transfer factor by antigen-coated polystyrene.

We have reported finding antigen-specific activity in human leukocyte dialysates (DLE) containing TF in the leukocyte migration inhibition (LMI) assay. To analyze this activity further, we have used polystyrene bound to antibody or to antigen as immunoadsorbent for DLE before pulsing nonimmune cells in the LMI assay. Candida-(CAN) immune or diphtheria toxoid-(TOX) immune DLE were depleted of all antigen-specific activity after absorption with specific antigen but not affected by absorption with specific antibody, respectively, and depletion of activity with antigen was abrogated by coating bound antigen with specific antibody before absorption of DLE. CAN-immune, TOX-immune DLE was selectively depleted for either CAN activity or TOX activity after absorption with CAN- or TOX-coated polystryrene, respectively, retaining its CAN-activity when absorbed with TOX and conversely retaining its TOX activity when absorbed with CAN; thus the antigen-specific activity binds to related but not unrelated antigen. The polystyrene-bound antigen-specific activity could be recovered by treatment with 8 M urea. We interpret these findings to suggest that such antigen-specific activity may be either a dialysable fragment of a T cell antigen receptor site, or a portion of the V-region, or a unique Ir gene product that assists in antigen presentation to other T cells.

Absorption↗

PubMed1982

Tc-99m-labeled polystyrene and cellulose macromolecules: agents for gastrointestinal scintigraphy.

Several polystyrene resin and cellulose derivatives were evaluated for potential use as Tc-99m-labeled particulate markers for studies of gastric emptying and intestinal transit time, and for imaging segments of the gastrointestinal tract. The polyamine and quaternary ammonium polystyrene resins bound pertechnetate (Tc--99m) anions effectively; the labeling efficiency was over 95% at physiological pH values. In-vitro stability studies of Tc-99m-labeled resins in simulated gastric and intestinal fluid showed that less than 8% of the label was released after 24 h. The commercial resins dowex 2-XB, AG 1-X2, and Bio-Rex 9, labeled with Tc-99m, may be used as particulate markers of solid digesta in external scintigraphic studies of the gastrointestinal tract. Dowex 2-X8 showed relatively more extensive uptake of pertechnetate and greater stability in simulated gastric and intestinal fluids.

Cellulose↗

PubMed1978

Mutagenicity study of workers employed in the styrene and polystyrene processing and manufacturing industry.

Mutagenicity studies were undertaken on lymphocytes from the following groups of persons exposed to styrene or polystyrene: one group from a styrene manufacturing plant, one from a polystyrene plant, and three from plants processing unsaturated polyester resins with different manufacturing methods. For all the groups the concentration of styrene in the atmosphere of the workplace was measured at various points and the amount of urinary mandelic acid was determined. In each case 100 metaphases were analyzed for chromosomal aberrations. The results were compared with reference groups.

Adult↗

PubMed1995

Binding characteristics of bovine serum albumin-aflatoxin B1 to polystyrene microtiter plates: importance of hapten to carrier protein molar ratio.

Binding characteristics of bovine serum albumin-aflatoxin B1 conjugates with high (1:54), medium (2:25) and low (1:9) hapten to carrier molar ratios, to the polystyrene microtiter plates are influenced by the stoichiometry of the hapten (Aflatoxin B1) to the carrier protein (bovine serum albumin). Conjugates with optimal hapten to carrier molar ratios (1:25) showed a better binding capacity to the polystyrene microtiter plate as compared to the conjugates with the high molar ratios in a non-competitive ELISA for aflatoxin B1. Denaturation of the conjugate with molar ratio of 1:54 in order to enhance its binding capacity, however, did not result in any significant improvement.

Aflatoxin B1↗

PubMed1976

IF-40. A new polystyrene microscope tray for immunofluorescent studies.

A polystyrene plate is described which was designed to replace microscope slides for routine immunofluorescent examinations. The plate has 40 flat indentations of 8 mm diameter. The plates can be sterilized and stored in plastic bags. They are well suited for drop preparations or application of cryostat slices of biopsy and necropsy material, and tissue cultures can be grown directly in the indentations. When compared with glass microscope slides, which have long been used for these purposes, the polystyrene plates offer a variety of advantages. Cells can be grown directly in the indentations without washing or pretreating the trays in any way. The indentations prohibit mixing of samples or reagents and enable the use of smaller quantities of reagents. Up to 40 samples can be worked up simultaneously on one plate, or a plate rack can be used for the processing of up to 400 samples at once. The use of a special stage enables easy microscoping of all 40 spots without further handling of the tray.

Fluorescent Antibody Technique↗

PubMedDate not supplied

[The use of modified polystyrene plates in solid-phase immunoenzyme analysis for the diagnosis of infections].

The practical aspects of the theory of the adsorption of bioligands on the plastic surface have been considered and discussed. The possibility of standardizing polystyrene plates, as well as obtaining plates with the predetermined level of adsorption activity with respect to given antigens (antibodies), has been shown with the use of the patented technology for the modification of polystyrene plates. The data on the adsorption of antigens used as an experimental model (human and rabbit immunoglobulin fractions) are presented, and an increase in adsorption activity has been shown with the use of modified plates. For practical confirmation, some examples of using these plates in actual assay systems intended for the evaluation of HBsAg carriership and antibodies to HIV are given. A considerable increase (2- to 10-fold) of the signal from positive samples has been shown to occur, the signal from negative samples remaining practically unchanged.

Adsorption↗

PubMed1993

Extracellular production of singlet oxygen by stimulated macrophages quantified using 9,10-diphenylanthracene and perylene in a polystyrene film.

The extracellular production of singlet oxygen (O2(1 delta g)) by stimulated macrophages was measured using a modification of our quantitative method initially developed to measure the intracellular production of O2(1 delta g) by neutrophils (Steinbeck, M. J., Khan, A. U., and Karnovsky, M. J. (1992) J. Biol. Chem. 267, 13425-13433). Glass coverslips were coated with the specific chemical trap for O2(1 delta g), 9,10-diphenylanthracene (DPA) and perylene, which is an internal standard, in a methylene chloride solution containing 0.3 mg/ml polystyrene. On evaporation, the polystyrene formed an even coating of DPA and perylene over the surface of a glass coverslip (PDP film). Unstimulated macrophages or macrophages stimulated with 4 beta-phorbol 12-myristate 13-acetate (PMA) or formyl-methionyl-leucyl-phenylalanine (fMLP) were then added to the PDP film in a darkened room and incubated at 37 degrees C for 30 min in a humidified 5% CO2 atmosphere. Both unstimulated and stimulated cells adhered to the PDP film in approximately equivalent numbers. Only stimulated cells produced measurable amounts of O2(1 delta g) in a dose-dependent response to either PMA or fMLP. The production of O2(1 delta g) by macrophages stimulated with PMA was maximal in response to 25 ng, 17.8 +/- 1.3 nmol of O2(1 delta g)/approximately 1.00 x 10(6) cells. The maximal response for fMLP was at a concentration of 1 microM, 18.4 +/- 1.0 nmol of O2(1 delta g)/approximately 1.00 x 10(6) cells. The specific detection of O2(1 delta g) by this method was confirmed by thermally releasing O2(1 delta g) from the DPA-O2(1 delta g) reaction product, DPA-endoperoxide, regenerating the original DPA compound. Production of O2(1 delta g) by the stimulated cells was inhibited 80-89% by the addition of 60-120 micrograms of superoxide dismutase, an enzyme that converts superoxide to hydrogen peroxide and ground state molecular oxygen or 79-84% with the addition of 2 mM histidine, an avid quencher of O2(1 delta g). Neither of these additions interfered with adhesion of the cells to the PDP film. The ability of superoxide dismutase to inhibit the production of O2(1 delta g) suggested that O2(1 delta g) was produced via a superoxide-dependent route. The ability of an oxidase to produce O2(1 delta g) secondary to superoxide production was substantiated further using a xanthine oxidase-acetaldehyde system. Purified xanthine oxidase produced both superoxide and O2(1 delta g), and their production was inhibited by the addition of superoxide dismutase.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1993

Sodium polystyrene sulfonate: a cation exchange resin used in treating hyperkalemia.

Sodium polystyrene sulfonate is a cation exchange resin used in the treatment of nonlife-threatening hyperkalemia. Administered orally or rectally, the resin can effectively reduce serum potassium concentrations in the neonate as well as the elderly. Proper administration, assessment of drug effectiveness, and detection and prevention of potential adverse side effects of sodium polystyrene sulfonate are the responsibility of the nephrology nurse.

Cation Exchange Resins↗