Hapten synthesis, monoclonal antibody production and immunoassay development for direct detection of 4-hydroxybenzehydrazide in chicken, the metabolite of nifuroxazide.

Derivatization is usually employed in immunoassay for detection of metabolites of nitrofurans and avoiding derivatization could be preferable to achieve an efficient screening. In the study, we designed four haptens of 4-hydroxybenhydrazide (HBH), the nifuroxazide metabolite. The effect of hapten structures on antibody affinity were evaluated and one monoclonal antibody was produced by using the Hapten C with a linear alkalane spacer arm. After optimization, an enzyme linked-immunosorbent assay (ELISA) was established with an 50% inhibition concentration of 0.25 ng mL-1 for HBH, which could ensure the direct detection of HBH without derivatization. The limit of detection of the ELISA for HBH was 0.12 µg kg-1 with the recoveries of 90.1-96.2% and coefficient of variation (CV) values lower than 9.1%. In conclusion, we produced several high affinity antibodies to HBH with new designed hapten and developed an icELISA for the direct detection of HBH without derivatization in chicken.

Study on the anaphylactoid of three phenolic acids in Honeysuckle.

ETHNOPHARMACOLOGICAL RELEVANCE: Chlorogenic acid (CA) is one of the major ingredients in Honeysuckle which exhibits anticancer, antibacterial, antiviral, hypoglycemic and anti-HIV activities. However, with the frequent emergence of anaphylactoid reactions of traditional Chinese medicine (TCM) injections which contains Honeysuckle in recent years, many researchers found that CA exhibited allergenicity. AIM OF THE STUDY: To explore the changes of content of CA, neochlorogenic acid (NCA) and cryptochlorogenic acid (CCA) during the preparation of Honeysuckle and evaluate the anaphylactoid of these three ingredients. MATERIALS AND METHODS: Two extracts of Honeysuckle were prepared by different methods and the content of CA, NCA and CCA were determined by high performance liquid chromatography (HPLC) analysis. Guinea pig and mast cells RBL-2H3 were utilized as the animal and cell model to investigate the anaphylactoid of these three ingredients. RESULTS: The content of CA decreased while CCA and NCA increased during the preparation of Honeysuckle. In vitro and in vivo studies showed that CA and CCA could significantly increase the plasma serotonin and ß-hexosaminidase levels in guinea pigs and induce the degranulation of RBL-2H3 cell, while NCA did not show such properties. In addition, CAA had a stronger effect than CA. CONCLUSION: We believed that both CA and CCA could cause anaphylactoid reaction while NCA could not. Moreover, the anaphylactoid of CCA is higher than CA. Our result demonstrated that CA is not the only cause of anaphylactoid reactions of TCM injections which contains Honeysuckle.

Tissue reactions after subcutaneous and intraosseous implantation of mineral trioxide aggregate and ethoxybenzoic acid cement.

Biocompatibility of mineral trioxide aggregate and ethoxybenzoic acid cement was investigated by subcutaneous and intraosseous implantation of the materials in rats. Tissue reactions were studied at 15, 30, and 60 days after implantation. Subcutaneous implantation of mineral trioxide aggregate initially elicited severe reactions with coagulation necrosis and dystrophic calcification; the reactions, however, subsided to mostly moderate with time. Subcutaneous implantation of ethoxybenzoic acid cement initially elicited mostly moderate reactions that subsided to mild in time. Osteogenesis was not observed with either material upon subcutaneous implantation indicating that neither material is osteoinductive. Reactions to intraosseous implants of both materials were less intense than with subcutaneous implantation. Osteogenesis occurred in association with intraosseous implants indicating that both materials are osteoconductive.

An improved method for the production of antibodies to lipophilic carboxylic hapten using small amount of hapten-carrier conjugate.

A rapid, simple and low cost procedure for preparing minute amount of hapten-protein conjugates was developed using 4-acetyl benzoic acid (ABA) and two other closely related small chromophoric haptens. The amide bond-generating mixed anhydride method of Erlanger was modified to promote conjugation to various proteins (bovine serum albumin, ovalbumin, casein and hemocyanin) or to a synthetic homopolymer (Poly-DL-lysine). The key process in this synthesis is the use of a reversed micellar medium allowing strong carrier haptenization as determined by spectrophotometric measurement at characteristic hapten absorption peaks. This coupling procedure is applicable to as little hapten material as 0.2 micromol and is disclosed to be most valuable for other rare lipid haptens which pose analytical problem in biological fluids and matrices. Specific mice polyclonal antibodies were produced following multiple intraperitoneal injections of (ABA)23-BSA conjugate as revealed by indirect and competitive ELISA. Calculated KD for the interaction of the antibodies with free ABA was found to be 5 X 10(-5)M.

The sensitizing capacity of atranorin.

The allergenic potential of the aromatic lichen substance atranorin has been investigated by means of the guinea pig maximization test of Magnusson & Kligman. Sensitivity was induced in 30% of the animals, which corresponds to a moderate allergenic capacity (grade III). This is in agreement with the clinically-observed frequency of 1.5% among our patients. A modified photoallergy test on the same animals was performed, but irradiation did not increase the number of positive reactions. 4 patients with proven contact sensitivity to atranorin, evernic, usnic or physodic acid, were examined with different dilutions from 0.001 to 0.1%. Irradiation of the test series did not provoke any clear-cut photoallergic reaction.

[Synthesis of phenol-antigen conjugates by reacting N-hydroxysuccinimidic esters of hydroxybenzoic acids with human serum albumin and bovine gamma globulin]. / Synthese von Phenol-Antigen-Konjugaten durch Umsetzung von N-Hyroxysuccinimidestern von Hydroxybenzoesäuren mit Humanserumalbumin und Rindergammaglobulin.

Salicylic acid, beta-resorcylic acid and gentisic acid were acetylated and then reacted with N-hydroxysuccinimide according to the DDC procedure to give the corresponding activated esters. The reaction of these N-hydroxysuccinimidic esters with human serum albumin and bovine gamma globulin yielded modified proteins containing hydroxybenzoyl residues linked to amino groups, the mode of linkage being of the acid amide type.