Contact allergy induced by bisphenol A diglycidyl ether leachables from aluminium tubes for pharmaceutical use.

BACKGROUND: Aluminium tubes for pharmaceutical use are internally lacquered with epoxy resins (ER) based on bisphenol A diglycidyl ether (BADGE). Recently, it was shown that remnants of ER polymerization like BADGE are extractable from epoxy-based coatings of commercially available tubes and may leach into semi-solid drug preparations. We aimed to evaluate the safety of BADGE-contaminated macrogol ointments in individuals sensitized to ER based on BADGE by use tests. METHODS: Repeated open application testing (ROAT) in 11 patients sensitized to ER based on BADGE with BADGE in macrogol ointments (3 mg/kg; 30 mg/kg, equivalent to BADGE concentration determined in macrogol ointment after storage in a commercially available tube; 300 mg/kg). RESULTS: The 30 mg/kg BADGE ointment elicited reactions in three patients, and another three patients reacted to 300 mg/kg BADGE ointment. No reactions to the vehicle control and 3 mg/kg BADGE were observed. CONCLUSIONS: Elevated BADGE concentrations in ER-coated aluminium tubes pose a risk of developing contact dermatitis to patients sensitized to ER based on BADGE. Quality standards are deemed necessary for the production of ER-coated aluminium tubes intended for pharmaceutical use and should consider the results of the present ROAT study.

Plasma haptoglobin concentration in swine after challenge with Streptococcus suis.

Eight 15-week-old pigs, reared under specific pathogen-free conditions, were inoculated with Streptococcus suis serotype 2. The animals were monitored before and after challenge by measuring rectal temperature, recording specific clinical symptoms and collecting blood samples for haptoglobin determination. Twenty-four hours after infection, the average haptoglobin plasma concentration of the animal group increased significantly and reached a maximum 4 days post-inoculation, followed by a constant mean level until the end of the trial on day 10. In spite of individual differences between the animals, an increase in haptoglobin concentration of at least 2.5 times above normal was observed in all infected pigs 1 day after challenge. Twenty-four hours after challenge, lameness was observed in five animals and an elevated body temperature was observed in seven of the eight experimental infected animals. These are the classical clinical symptoms of streptococcal infection. Haptoglobin was shown to increase in acute S. suis infection in pigs.

Nephelometric determination of haptoglobin plasma concentrations in fattening pigs.

The haptoglobin plasma concentrations in 110 fattening pigs living on three commercial farms and in 28 animals on the university pilot farm were measured using a nephelometric detection method based on an immunoassay. Following calibration of the automated analyser (Nephelometer BN 100) with a human haptoglobin standard, the measurements were performed using anti-human antiserum from rabbits. Differences in age, gender or breed of apparently healthy animals seem to have no influence on the plasma concentration of the protein. The average plasma level of haptoglobin in animals suffering from acute respiratory diseases was significantly higher. Furthermore, an increase was observed in animals without clinical symptoms living on a farm characterized by obvious defects in housing conditions. Comparison studies of the nephelometric method by use of a human or porcine standard for calibration and different anti-human or anti-porcine antisera with radial immunodiffusion as a reference method resulted in high correlation coefficients for all variations. Optimal accuracy was obtained by calibrating the analyser with a porcine standard. Haptoglobin determinations have been shown to be a useful tool for health monitoring during the integrated pig-production process, allowing recognition of performance-reducing conditions. The immunonephelometric determination method is suitable for quantifying porcine plasma haptoglobin for routine checks. The use of animal-specific standards for calibration improves the accuracy of this method.

Determination of lactate dehydrogenase activity and urea content in milk by dry chemistry.

Comparison of the new technique of dry chemistry (EKTACHEM 700-XR, Eastman Kodak Co., USA) with conventional wet chemistry (HITACHI 717, Boehringer Mannheim, Germany) for quantitations of lactate dehydrogenase activity and urea content in bovine milk resulted in correlation coefficients of more than 0.9 even when measuring fresh raw milk by dry chemistry.

Improved purification and some properties of bovine lysosomal carboxypeptidase B.

Lysosomal carboxypeptidase B (peptidyl-L-amino-acid hydrolase, EC 3.4.18.1) from bovine spleen purified to apparent homogeneity was found to have a molecular weight of 52 000 in the absence and of 25 000 in the presence of urea, determined by gel filtration, indicating the existence of two subunits of identical size. The amount of approx. 15% carbohydrate estimated after cleavage by endoglycosidase H was shown to be insignificant for enzymatic activity. The isoelectric focusing separated lysosomal carboxypeptidase B into several protein bands - each enzymatically active - with a range of isoelectric points between 4.6 and 5.2. The titration of the sulphydryl group in the active site of the enzyme with the proteinase inhibitor E-64 yielded one thiol group per molecule. A maximum of activation was achieved by the addition of selenocystamine together with dithioerythritol and EDTA in the incubation solution. Under these conditions the carboxypeptidase hydrolyzed benzoylglycylarginine (80 kat/mol enzyme), benzoylarginine amide (38 kat/mol enzyme) and carbobenzoxyglutaryltyrosine (110 kat/mol enzyme). Slight enzymatic activities towards benzoylarginine 2-naphthylamide and benzoylarginine p-nitroanilide could be measured. With the oxidized insulin B chain, lysosomal carboxypeptidase B exhibited only carboxypeptidase activity.