Detection of hormonal anabolic compounds in calf urine and unverified growth-promoting preparations: Application of the AR-LUX bioassay for screening and determination of androgenic activity

Despite a ban by the European Union, the use of anabolic steroids and repartitioning agents in cattle is still occasionally observed. Due to continuing improvements in analytical techniques, very low detection limits for individual compounds have been achieved. In response to these developments, cocktails composed of several steroids have been...

The effect of gregariousness in cyprid settlement assays

The in vitro settlement assay using cyprids of Balanus, amphitrite is an important tool in basic and applied research. The aim of this study was to quantify the effect of gregariousness within these assays, and to determine the interaction between gregariousness and container size, and settlement promoters and inhibitors. Assays with 1, 5, 10,...

Biosensors and multiple mycotoxin analysis

An immunochemical biosensor assay for the detection of multiple mycotoxins in a sample is described.The inhibition assay is designed to measure four different mycotoxins in a single measurement, following extraction, sample clean-up and incubation with an appropriate cocktail of anti-mycotoxin antibodies.The different mycotoxins could be...

Statistically designed experiments in a tiered approach to screen mixtures of Fusarium mycotoxins for possible interactions

This paper presents a test strategy to detect interactive effects between several mycotoxins using a DNA synthesis inhibition assay in L929 cells. The joint action of the Fusarium mycotoxins T-2 toxin (T2), deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and fumonisin (FB1) was studied in a tiered approach. In the first stage, the...

Chronic pulmonary effects of respirable methylene diphenyl diisocyanate (MDI) aerosol in rats: Combination of findings from two bioassays

Two independent bioassays are available which have examined the potential carcinogenicity of monomeric and polymeric methylene diphenyl diisocyanate (MDI) following long-term inhalation exposure in rats. These studies are not directly comparable, however, due to differences in design and conduct of the in-life phase, and differences in...

The β-adrenoceptor agonist clenbuterol is a potent inhibitor of the LPS-induced production of TNF-α and IL-6 in vitro and in vivo

Objective and Design: To investigate the suppressive effects of the β-agonist clenbuterol on the release of TNF-α and IL-6 in a lipopolysaccharide (LPS)-model of inflammation, both in vitro and in vivo. Material and Subjects: Human U-937 cell line (monocyte-derived macrophages), and male Wistar rats (200-250 g). Treatment: U-937 macrophages were...

Long- and medium-term carcinogenicity studies in animals and short-term genotoxicity tests.

About the order in aerobic heterotrophic microbial communities from hydrocarbon-contaminated sites

The organizational structure of communities of aerobic heterotrophic bacteria was studied by means of physiological and molecular typing of the members of arbitrary samples of isolates, ASsI. The isolate sample assay (ISA) was applied to three different hydrocarbon-polluted sites: a dry windrow pile for bioremediation of waste oil-contaminated...

Repetitive testing of TBTO, Sea-Nine 211 and farnesol using Balanus Amphitrite (Darwin) cypris larvae: Variability in larval sensitivity

Settlement inhibition assays with mass cultured cypris larvae of the barnacle Balanus amphitrite are widely used in (anti)fouling research. In this study, TBTO, Sea-Nine 211 and farnesol were tested repeatedly using multiple batches of larvae to study variability in larval sensitivity. There were significant differences in EC50 values among...

Statistically designed experiments to screen chemical mixtures for possible interactions

For the accurate analysis of possible interactive effects of chemicals in a defined mixture, statistical designs are necessary to develop clear and manageable experiments. For instance, factorial designs have been successfully used to detect two-factor interactions. Particularly useful for this purpose are fractionated factorial designs,...

A sensitive bioimmunoassay for thrombin-cleaved two-chain urokinase-type plasminogen activator in human body fluids

Thrombin cleaves single-chain urokinase-type plasminogen activator (scu-PA) into a two-chain form (tcu-PA/T), which is virtually inactive in plasminogen activator assays. Little is known about the physiological importance of tcu-PA/T. To examine the occurrence of tcu-PA/T in vivo, we developed a sensitive and specific bioimmunoassay (BIA) for...

A bio-immuno assay to determine free tissue-type plasminogen activator (t-PA) in Stabilyte® plasma

This article describes a two-step bio-immuno assay (BIA), which determines active (free) tissue-type plasminogen activator (t-PA) in (acidified) plasma. Plasma samples, diluted in buffer of pH 6.0, are added to the wells of a microtiter plate containing an immobilised monoclonal antibody which binds t-PA without affecting t-PA activity. After an...

Nucleic acid detection with surface plasmon resonance using cationic latex

An affinity sensor based on Surface Plasmon Resonance (SPR) was used to detect nucleic acids. SPR is an optical technique that is able to detect small. changes in the refractive index of the immediate vicinity of a metal surface. After a specific amplification of DNA, achieved using the polymerase chain reaction (PCR), detection was accomplished...

Enhanced surface plasmon resonance inhibition test (ESPRIT) using latex particles

The pregnancy hormone human chorionic gonadotropin (hCG) was used as a model antigen to describe a new assay, the Enhanced Surface Plasmon Resonance Inhibition Test (ESPRIT). It was shown that the introduction of sub-micron latex particles instead of anti-antibodies in an enhancement step improved the sensitivity of the assay by a factor of 30....

In vitro diagnosis of fibrinolysis: Present status and desired improvements

Chemicals/CAS: Biological Markers; Plasminogen Activator Inhibitor 1; Tissue Plasminogen Activator, EC 3.4.21.68.

Short-term tests in the framework of carcinogen risk assessment to man

Short-term tests designed to detect possible carcinogenicity have been extensively refined during the last years. Presently, many more or less simple and convenient systems are available to detect mutations, chromosome effects, DNA damage, and malignant transformation. Although their relevance to carcinogenicity is often reasonably good,...

Mycotoxins

Chemicals/CAS: 3 nitropropionic acid, 504-88-1; aflatoxin B1, 1162-65-8; aflatoxin B2, 7220-81-7; aflatoxin G1, 1165-39-5; aflatoxin G2, 7241-98-7; aflatoxin, 1402-68-2; diacetoxyscirpenol, 2270-40-8; fumagillin, 23110-15-8; gliotoxin, 37273-88-4, 67-99-2; kojic acid, 501-30-4; luteoskyrin, 21884-44-6; ochratoxin, 303-47-9, 37203-43-3;...

Incomplete sedimentation of Rauscher leukaemia virus particles during ultracentrifugation