Hypochlorous acid is antipruritic and anti-inflammatory in a mouse model of atopic dermatitis.

BACKGROUND: It has been reported that topical hypochlorous acid (HOCl) formulations lead to relief of itch in human patients with atopic dermatitis; however, the specific antipruritic mechanism of action remains unclear. OBJECTIVE: To confirm itch relief and reduction of lesions in a mouse model of atopic dermatitis and to elucidate possible HOCl's mode of action. METHODS: In this study, the effects of topical administration of HOCl hydrogel (0.05%) on atopic dermatitis-like lesions in NC/Nga mice model as well as in vitro effects of HOCl on dorsal root ganglia neurons and mouse bone marrow-derived dendritic cells (mBMDCs) were investigated. NC/Nga mice were sensitized with house dust mite allergen and treated topically with HOCl hydrogel both preventively and therapeutically against established lesions. Allergen challenge was continued during HOCl hydrogel application. RESULTS: Treatment with HOCl hydrogel prevented the development of lesions and scratching bouts during the whole observation period. When administered after full development of lesions, HOCl reduced lesions and scratching behaviour to a similar extent as a positive control 0.1% betamethasone dipropionate ointment. The reduced inflammatory response by HOCl treatment was demonstrated by reduced secretion of inflammatory cytokines in affected skin tissue from NC/Nga mice. In addition, HOCl significantly reduced IL-12 production in mBMDC. The diminished scratching behaviour was confirmed by impaired response to several pruritogens in dorsal root ganglia neurons excised from NC/Nga mice after termination of the studies. The response to the stimuli was also reduced by pre-incubation of sensory neurons from untreated BALB/c mice with 0.0001% HOCl. CONCLUSIONS AND CLINICAL RELEVANCE: These data indicate a direct reduction in sensory response by HOCl, leading to significantly reduced itch and inflammation in vivo.

High-performance liquid chromatographic method for the simultaneous detection of the adulteration of cereal flours with melamine and related triazine by-products ammeline, ammelide, and cyanuric acid.

Melamine has been used for the adulteration of cereal flours in order to increase their apparent protein content. Crude melamine may contain several by-products, i.e. ammeline, ammelide, and cyanuric acid. The simultaneous analysis of all four chemicals is difficult because of the formation of an insoluble salt between melamine and cyanuric acid. A simple and convenient high-performance liquid chromatography (HPLC) method for the detection of the adulteration of cereal flours with all four chemicals is proposed herein. The precipitate formation between melamine and cyanuric acid was prevented by using alkaline conditions (pH 11-12) for both standards preparation and sample extraction. The method uses matrix-matching, which involves the construction of a calibration curve on a blank (negative control) matrix, which is then used for the quantitation of melamine and by-products in adulterated (positive) samples. Matrix-matching compensates for analyte losses during sample preparation, and for matrix effects. The method was successfully applied to wheat, corn, and rice flours, and is expected to be applicable (with some modifications) to soy flour as well. The method allows for the detection of melamine, ammeline, and ammelide at approximately 5 microg g(-1), and cyanuric acid at approximately 90 microg g(-1) in wheat flour.

Trace analysis of perchlorate anion in selected food products by reverse-phase liquid chromatography-tandem mass spectrometry.

An alternative, rapid, and reproducible method of analysis for perchlorate in selected food products (fruit and vegetable juice, milk, and bottled water) was developed and validated. Improvements over previous methods were achieved by the use of a rugged and inexpensive C18 column, a multi-mode OASIS HLB solid-phase extraction cartridge for sample clean-up, and acetic acid for pH adjustment and protein precipitation. The hydrophobicity of the perchlorate anion gives it good retention and separation characteristics on C18 chromatographic columns. The C18 column allowed for the use of 90% of acetonitrile at a low flow rate (0.3 ml min(-1)), without splitting, and could also be regenerated with organic solvents, unlike an ion-exchange column. Perchlorate levels in selected commercial food samples were: <1.0-2.1 ng g(-1) (fruit and vegetable juices, reported here for the first time), <1.0-5.0 ng g(-1) (milk), and <1.0 ng g(-1) (bottled water).