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At least 19 recordsLinked to original sources
PubMed1989

Culture of human vascular endothelial cells on a positively charged polystyrene surface, primaria: comparison with fibronectin-coated tissue culture grade polystyrene.

Two culture surfaces, fibronectin-coated tissue culture grade polystyrene and a surface-modified polystyrene called Primaria (Falcon), were compared. The morphological (contact inhibition and cobblestone aspect), biological (production of von Willebrand factor and prostacyclin) and physiological (growth activity, non-thombogenicity and regeneration after mechanical injury) properties of human endothelial cells were studied. Adhesion and growth of endothelial cells at low and clonal density were identical on both substrates and the biological properties were preserved. Regeneration of injured endothelium was less easy to study on Primaria polystyrene because the extracellular matrix was damaged during the lesion process. Nevertheless, Primaria polystyrene can easily be substituted for fibronectin coating in growth experiments, especially at very low seeding density.

Cell Adhesion↗
PubMed1977

[Serologic-nephelometric method for the detection of allergic reactions to small-molecular drugs using polystyrene sodium particles instead of soluble polystyrene sulfonate sodium as pharmaceutic aids].

The previously developed two-step method using soluble polystyrene sulfonate-Na for the detection of allergic reactions to small molecular drugs has been replaced by a one-step method using particles of the same substance. The new method is simpler to perform. Particulate polystyrene sulfonate is commercially available. The drug is added in increasing concentrations to diluted serum samples and the light scattering is measured with a highly sensitive nephelometer. Both the specific serum factor in the patient's serum (globulins) and the non-specific factor contained in most fresh human sera are particularly labile.

Antibody Formation↗
PubMed1992

Lithium absorption prevented by sodium polystyrene sulfonate in volunteers.

STUDY OBJECTIVE: To determine if sodium polystyrene sulfonate prevents absorption of lithium in human beings. DESIGN: Prospective, crossover study. TYPE OF PARTICIPANTS: Healthy volunteers age 22 to 34 years (three women and three men). INTERVENTIONS: After an eight-hour fast, subjects ingested 0.5 mEq/kg (18.5 mg/kg) lithium carbonate. One hour later, they ingested either 857 mg/kg sodium polystyrene sulfonate in 4 mL water/g sodium polystyrene sulfonate (experimental) or an equal volume of water without sodium polystyrene sulfonate (control). MEASUREMENTS AND MAIN RESULTS: Serum lithium levels were drawn zero, one, two, three, four, six, eight, ten, 12, and 24 hours after lithium ingestion. The sodium polystyrene sulfonate group had a smaller mean area under the serum concentration curve (11.6 +/- 1.0 mEq/L.hr versus 13.6 +/- 1.5 mEq/L.hr, P < .001) and lower mean highest measured lithium level (0.85 +/- 0.11 mEq/L versus 1.05 +/- 0.10 mEq/L, P < .05) compared with the control group. There was no significant difference in 24-hour urine lithium excretion or in serum sodium and potassium levels. CONCLUSION: Sodium polystyrene sulfonate administration decreased absorption of lithium after a lithium carbonate overdose. Sodium polystyrene sulfonate may be useful clinically for gastric decontamination after lithium overdoses.

Absorption↗
PubMed1975

New useful reagents for peptide synthesis. Insoluble active esters of polystyrene-bound 1-hydroxybenzotriazole.

Insoluble 1-hydroxbenzotriazole-bound polystyrene was prepared through a series of chemical modifications of commercially available polystyrene. Reaction of 3-nitro-4-chlorobenzyl alcohol or of 3-nitro-4-chlorobenzyl bromide with polystyrene in the presence of aluminium trichloride yielded (3-nitro-4-chloro)benzylated polystyrene. Upon reaction with hydrazine it was converted to (3-nitro-4-hydrazine) benzylated polystyrene which was cyclized, by acidolysis, to yield 1-hydroxybenzotriazole-bound polystyrene. This was coupled, using N, N' -dicyclohexylcarbodiimide as the coupling agent, to many N-blocked amino acid derivatives, yielding polymeric polystyrene-bound active esters. Such derivatives are highly reactive and their efficacy in the synthesis of several peptides, including that of the tetrapeptide Boc-L-Leu-L-leu-L-Val-0bzl-L-Tyr-0Bzl and of thyrotropin-releasing hormone was demonstrated.

Dipeptides↗
PubMed1991

Interactions of proteins in human plasma with modified polystyrene resins.

Investigations are reported on the composition of protein layers adsorbed from plasma to various modified polystyrene resins. As well as polystyrene itself, polystyrene bearing sulfonate groups in the benzene rings, and polystyrene sulfonate in which the sulfonate groups were converted to amino acid sulfamide, were investigated. Some of these resins were shown in previous work to have anticoagulant properties. To study the adsorption of proteins from plasma, the resins were exposed to citrate anticoagulated human plasma for 3 h. Adsorbed proteins were then eluted sequentially by 1M Tris buffer and 4% SDS solution, and examined by SDS-PAGE. The gel patterns were similar on all resins except polystyrene. From the MWs of the gel bands, the major protein component appeared to be fibrinogen. Smaller amounts of plasminogen, transferrin, albumin, and IgG were also present. In addition, Ouchterlony immunoassay of the eluates from one resin gave positive identification of complement C3, fibronectin, IgG, and IgM. Many other minor gel bands remain unidentified. A consistent finding for all resins was the presence of plasmin-type fibrinogen degradation products though the amounts varied with resin type. It is concluded from this (and from experiments showing FDP formation when fibrinogen was absorbed to the resins, from buffer containing a trace of plasminogen) that the functional groups in these materials promote the adsorption of plasminogen and its activation to a plasmin-like molecule. It appears from the substantial quantities of fibrinogen adsorbed to these materials after 3 h exposure to plasma that the Vroman effect (giving transient adsorption of fibrinogen) is not operative on these materials. It is hypothesized that specific interactions occur between fibrinogen and sulfonate groups.

Adsorption↗
PubMed1978

Interrelationships between soil microorganisms and polystyrene.

Transmission and scanning electron microscopy along with autoradiographic procedures were used for evaluating the interrelationship between soil microorganisms and polystyrene. Two hypotheses, allowing to explain the properties of polystyrene as a soil conditioner, were investigated: the first is concerned with a possible action of soil microorganisms on the compound; the second, reciprocally, with the polystyrene interference on microorganisms. Radioactivity translocation of 14C-Ecolyte-polystyrene along fungal hyphae and asexual fructification of strains, isolated from soil, as well as cytological modification at the cell wall level of the same microfungi, cultivated in the presence of polystyrene have been ascertained.

Cladosporium↗
PubMedDate not supplied

Sensory analysis of polystyrene packaging material taint in cocoa powder for drinks and chocolate flakes.

Polystyrene packaging material taint was sensorily evaluated in cocoa powder for drinks and chocolate flakes using short-cut signal detection measures on differences between control and test samples and on recognition of styrene. No differences were observed in cocoa powder for drinks and plain chocolate flakes treated with 0.5 dm2 polystyrene of 1 mm thickness. However, differences were detected in milk chocolate flakes and plain chocolate flakes, which were in contact with a larger area or thicker polystyrene packaging material. The latter results were confirmed by the styrene recognition test, so polystyrene is a potential source of off-flavour for chocolate products. The amount of residual styrene in the polystyrene used was about 320 ppm, while the amounts of styrene ranged from 7 to 132 ppb in cocoa drinks and from 414 to 1447 ppb in chocolate flakes.

Cacao↗
PubMed1989

Cytotoxicity due to a reaction between polystyrene and constituents of stool.

Cell monolayers grown in polystyrene culture plates and in glass tubes are routinely used in virology laboratories around the world for virus isolation and identification. Monolayers of different types of cells grown in polystyrene culture plates were found to show a strange cytotoxicity when inoculated with stool samples from healthy children from Bangladesh. When inoculated with 0.2 ml of a 10% stool sample 100% (80/80) of the cell monolayers established in polystyrene plates showed cytopathy by 4 days and 60% (48/80) within first 2 hours of sample inoculation. In contrast only 4% (4/90) of samples inoculated in the same type of cell monolayers but established in glass cell culture tubes showed cytopathy by 4 days; out of these 4 only 2 (2%) showed cytopathy in the first 2 hours. Cytotoxicity could be reduced to half when the amount of inoculated stool sample was reduced by half in cases where polystyrene was used as the substrate. This difference of cytopathy under two different circumstances (polystyrene substrate versus glass substrate) was statistically significant (P less than 0.001).

Cell Survival↗
PubMed1992

Role of serum vitronectin and fibronectin in adhesion of fibroblasts following seeding onto tissue culture polystyrene.

The suitability of polymeric biomaterials as surfaces for the attachment and growth of cells has often been investigated in tissue culture. In this study the contribution that adsorption of serum fibronectin (Fn) or vitronectin (Vn) make to the attachment and spreading of fibroblast cells during the first 90 min following seeding was determined for two modified tissue culture polystyrenes, as model biomaterial surfaces. The amount of serum Vn and Fn which adsorbed onto tissue culture grade polystyrene (TCP) from different serum concentrations over the range of 0.1-30% (v/v) were determined and compared to attachment of cells of the BHK-21 and HT1080 fibroblast lines. There was no simple correlation between the amount of Fn or the amount of Vn adsorbed and cell attachment and spreading. The requirement for Fn or Vn for attachment and spreading of BHK-21 or HT1080 cells onto modified polystyrene (either TCP or to Primaria) during the first 90 min of cell culture was directly tested by selective removal of Fn or Vn from the serum prior to addition to the culture medium. Attachment and spreading of BHK-21 or HT1080 cells onto TCP or Primaria surfaces were reduced in a concentration-dependent manner when the cells were seeded in medium containing 2% (v/v) or higher concentrations of Vn-depleted serum. BHK-21 cells or HT1080 cells seeded in medium containing Fn-depleted serum (which contained Vn) attached and spread onto TCP or Primaria. Both BHK-21 cells and HT1080 cells failed to attach to TCP or Primaria when seeded in medium containing serum depleted of both Vn and Fn. The requirement for serum Vn or Fn for fibroblast attachment to TCP was also tested using cells of a human dermal fibroblast strain. The attachment of the dermal fibroblasts to TCP during the first 90 min of culture was not decreased by depletion of Vn from the 15% (v/v) serum, but there was a reduction in the proportion of the attached cells which had spread. Selective depletion of serum Fn did not have any effect on either cell attachment or spreading. Our results show that for fibroblast cells, particularly with cell lines such as BHK-21 or HT1080 but also with cell strains, the first binding of cells onto tissue culture polystyrene when plated in medium containing serum is a result of adsorption onto the surface of serum Vn. The adsorption of serum Vn onto the surface overcomes the effect of serum components which tend to decrease cell attachment.

Adsorption↗
PubMed1989

Preparation of diazotized polystyrene latex and its use in agglutination assays.

The preparation of this immunological latex consisted of the following steps: the synthesis of polystyrene, polynitrostyrene, polyaminostyrene and polystyrene diazonium salt latex. The quantities of emulsifier and initiator used in the synthesis of the polystyrene latex were much larger than those used in the conventional method. Reduction of the polynitrostyrene latex involved adding latex dropwise to a large excess of 6% sodium hydrosulphite-2 N potassium hydroxide solution with sodium lauryl benzene sulphonate as an emulsifier. When the mixture was heated at 70 degrees C for 4 h, the emulsion of polyaminostyrene was diazotized. The polystyrene diazonium salt latex obtained was capable of combining with 20-40% by weight of antibody protein. The immunopolystyrene diazonium latex reagents showed a positive agglutination reaction of 78-91% when mixed with serum from patients with leptospirosis and two other infectious diseases. The test, which can be completed within 3 min has been used to assay over 1200 patient samples.

Agglutination Tests↗
PubMed1989

Glycocalicin binding to von Willebrand factor adsorbed onto collagen-coated or polystyrene surfaces.

In order to analyze the interaction of platelets with von Willebrand factor (vWF) and collagen, we studied the binding of glycocalicin (GC) and formalin-fixed platelets to vWF adsorbed onto uncoated or collagen-coated polystyrene surfaces. These studies show that three-fold more vWF binds to collagen-coated polystyrene than to polystyrene coated with fibrin monomer or fibrinogen. At saturation, 37 +/- 2.9 ng vWF bound to the collagen-coated wells, compared to 12.8 +/- 5.4 ng, and 10.9 +/- 2.7 ng of vWF bound to wells coated with fibrin monomer and fibrinogen, respectively. GC also bound significantly more to collagen-coated wells than to wells coated with fibrinogen, and this binding was increased approximately two-fold (from 7 +/- 0.65 ng to 14 +/- 1.1 ng) in the presence of vWF adsorbed to the collagen-coated surface. Only 2 ng of GC was bound to 3000 ng of vWF when the latter was adsorbed directly onto a polystyrene surface. In contrast, GC binding to vWF adsorbed onto a collagen-coated surface was enhanced 600-fold with 7.0 ng of GC bound to 18 ng of immobilized vWF. Formalin-fixed platelets showed little binding to vWF adsorbed onto the microtiter wells. At saturation, 7 x 10(4) platelets bound to 3000 ng of vWF; a 6-fold increase in platelet binding was observed using collagen-coated wells and this binding was increased even further in the presence of vWF, resulting in 250-fold increase in platelet binding to vWF when the latter was adsorbed onto a collagen surface. These studies suggest that (1) GC is involved in platelet binding to collagen and this binding is increased by vWF; (2) GC binding to vWF is enhanced by the collagen-coated surface; (3) the adsorption of vWF onto a collagen surface may induce conformational changes in vWF that promote its interaction with GC or glycoprotein Ib.

Adsorption↗
PubMed1992

Effect of sodium polystyrene sulfonate on lithium bioavailability.

STUDY OBJECTIVE: To examine the effect of a single dose of sodium polystyrene sulfonate and sorbitol on lithium absorption. DESIGN: Prospective, randomized, crossover. SETTING: University teaching hospital. TYPE OF PARTICIPANTS: Healthy volunteers. INTERVENTIONS: Subjects ingested 600 mg lithium carbonate on two occasions, with and without 30 g concomitant sodium polystyrene sulfonate. Blood samples were drawn up to 24 hours after ingestion and assayed for serum lithium concentration. MEASUREMENTS AND MAIN RESULTS: Compared with control, sodium polystyrene sulfonate and sorbitol reduced the area under the lithium serum concentration-time curve by 11.33%, reduced the mean observed peak serum lithium concentration 0.07 +/- 0.08 mmol/L, and delayed the time to the mean observed peak serum lithium concentration by 2.04 +/- 2.40 hours. CONCLUSION: Sodium polystyrene sulfonate and sorbitol may be used in patients immediately or shortly after ingestion of a significant acute overdose of lithium in situations in which hemodialysis cannot be instituted promptly.

Absorption↗
PubMedDate not supplied

On the constancy in composition of polystyrene and polymethylmethacrylate plastics.

Variations in the atomic composition, and mass and electron densities of polystyrene and polymethylmethacrylate (PMM) plastics were assessed from experimentally determined mass attenuation coefficients for 125I and 137Cs gamma rays. The means and standard deviations in the mass densities of 16 samples of PMM and 10 samples of polystyrene were found to be 1.174 +/- 1.4% and 1.042 +/- 0.6% g/cm3, respectively. Based upon transmission measurements on various solutions of ethyl alcohol in water, the standard deviations in the effective atomic numbers of PMM and polystyrene were determined to be 0.77% and 1.3%, respectively. Based upon experimentally determined mass attenuation coefficients for 137Cs, the standard deviations in electron density for PMM and polystyrene were 0.5% and 1.2% respectively. Similar measurements on tap water and two grades of distilled water failed to detect any differences in atomic composition.

Methylmethacrylates↗
PubMed1978

Superoxide production from human polymorphonuclear leucocytes stimulated with immunoglobulins of different classes and fragments of IgG bound to polystyrene dishes.

Polystyrene surfaces coated with proteins at alkaline pH were found to be useful to investigate the stimulation of neutrophils independently of phagocytosis. Human neutrophils, when exposed to appropriate stimuli, release superoxide anion (O2-). We have measured superoxide dismutase-inhibitable cytochrome c reduction by cells stimulated with various kinds of protein coated on polystyrene dishes. Native immunoglobulins in solution did not stimulate O2- generation in neutrophils. IgG and IgA adherent to polystyrene dishes stimulated O2- generation in neutrophils, but IgM, IgD, IgE, albumin, Fab, and Fc of IgG on polystyrene dishes did not.

Humans↗
PubMed1992

The physical and functional behavior of capture antibodies adsorbed on polystyrene.

Six monoclonal and two polyclonal antibodies to fluorescein (FLU) were affinity purified and immobilized on Immulon 2 polystyrene as capture antibodies (CAbs): (a) by passive adsorption at pH 9.6, (b) via a streptavidin bridge to a biotinylated carrier molecule, and (c) via an antiglobulin which had been previously adsorbed passively to the polystyrene. Data show that less than 3.0% of the binding sites of monoclonal CAbs and approximately 5-10% of those of polyclonal CAbs were capable of capturing antigen (FLU4.2-BSA) after passive adsorption. Immobilization of CAbs via an antiglobulin or a streptavidin bridge, resulted in the preservation of antibody binding sites to greater than 70% for some monoclonals although immobilization via the streptavidin bridge resulted in the highest number of functional sites/well. The data presented are consistent with studies on other adsorbed proteins which demonstrate that passive adsorption on polystyrene results in the loss of protein function. Furthermore, these data show that generally less than half of the binding sites of antibodies available in solution are available after solid-phase immobilization even when non-adsorptive methods are employed. Some polyclonal anti-FLU also have lower average avidity following passive adsorption compared with CAbs immobilization via a streptavidin bridge. Immunochemical studies revealed that adsorbed polyclonal-CAbs performed like monoclonals when tested with multivalent antigens (FLU10-IgA) but in an expected heterogeneous manner in Scatchard plots when tested using univalent FLU-insulin. This observation implied cross-linking of immobilized CAbs by the multivalent antigen. Because only 5-10% of adsorbed polyclonal CAbs are active, the survivors must be non-randomly distributed in clusters to explain the cross-linking. This was confirmed by scanning electron microscopy which gave rise to the hypothesis that antibodies which retain activity after adsorption, are those present in clusters, i.e., the functional adsorbed CAb is an antibody cluster. Data presented in this report on the behavior of adsorbed CAbs, and reviewed from the work of others for various adsorbed proteins, indicate that the method of passive adsorption at pH 9.6, which is widely used in popular microtiter ELISAs, and which has in many ways revolutionized immunoassay, is a method of protein denaturation. Assayists that utilize passive adsorption of proteins on hydrophobic supports as part of their research need to be cognizant of this phenomenon, while inventors of immunoassay should develop alternative methods of immobilization which do not destroy 90% of the functional activity of solid-phase reactant.

Adsorption↗
PubMed1990

Plasmatic antiproteinase activity enhancement by insoluble functionalized polystyrene surfaces.

Antithrombogenic functional polymer surfaces have been obtained by grafting heparin or by substituting insoluble polystyrene with sulphonate and/or amino acid sulphamide groups. Their heparin-like properties have been related to their catalytic effects on the antithrombin III - thrombin complex formation. Amongst these antithrombogenic surfaces, this study demonstrates that some insoluble amino acid sulphamide derivatives of polystyrene strongly potentiate heparin cofactor II, in addition to antithrombin III. In contrast, an insoluble polystyrene sulphonate and, to a lesser extent, an insoluble heparin copolymer, are better catalysts of antithrombin III. It is hypothesized that such different behaviours result from different conformations of the species adsorbed onto the surfaces. The conclusions support the possible use of such amino acid sulphamide groups to prepare antithrombogenic surfaces in contact with blood.

Antithrombin III↗