Publications by authors named "Siegrun Mohring"

Fluoroquinolones are important therapeutics in human and veterinary medicine. This study aimed to retrospectively analyse sedimentation dusts from intensive-livestock-farming barns for fluoroquinolones and investigate the association between resistant Escherichia coli and the detected drugs. Sedimentation-dust samples (n = 125) collected (1980-2009) at 14 barns of unknown-treatment status were analysed by HPLC and tandem-mass spectroscopy to detect enrofloxacin, ciprofloxacin, marbofloxacin, and difloxacin.

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The application of antibiotics including fluoroquinolones to farming animals is widespread and may lead to the development of antibiotic resistance and other environmental effects. To calculate environmental loads and for a proper risk assessment it is necessary to determine the antibiotic concentration in feces. Therefore, a new liquid-liquid extraction method combined with HPLC-MS/MS for the detection of marbofloxacin, ciprofloxacin, enrofloxacin and difloxacin in chicken feces was developed.

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Fluoroquinolones are synthetic antibiotics which are frequently used in veterinary medicine e.g. for the treatment of poultry.

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Background: This study assessed the photochemical fate of nine sulfonamides (sulfamerazine, sulfanilamide, sulfamethoxypyridazine, sulfamethoxazole, sulfachloropyridazine, sulfamethazine, sulfadiazine, sulfathiazole and sulfadimethoxine) during a 6h irradiation period with UVA/UVB-light and UVA-light and over 7 days under natural (sunlight) conditions. The cell growth inhibition effect and cytotoxicity of sulfonamides and their photodegradation products was investigated over 24 and 48 h with murine fibroblasts and keratinocytes. Antibacterial activity of the degradation products was studied using the Geobacillus stearothermophilus var.

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Background: The influence of matrix effects in LC-MS/MS analysis of biological samples can be enormous and has to be evaluated during method development. Phospholipids, which are present in considerable quantities in biological fluids, are supposed to cause matrix effects when co-eluting with analytes. Therefore, the reduction of phospholipids should lead to the minimization of matrix effects.

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Cytotoxic drugs, previously used only in human medicine, are increasingly utilized for cancer treatment in veterinary practice. We developed and validated a liquid chromatography (LC)-electrospray ionization-tandem mass spectrometry (MS-MS) method to determine vincristine, vinblastine, cyclophosphamide, and doxorubicin in canine urine. Sample pretreatment consisted of liquid-liquid extraction, and LC separation was carried out on an RP C(18) column employing a 0.

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Antibiotics, most notably sulfonamides and tetracyclines, are frequently used veterinary pharmaceuticals in animal husbandry. A new field of application for animal manure is in biogas plants for generating environmentally friendly energy. As a result, antibiotics contained in manure may still reach the environment as fermentation residues are also used on agricultural fields as fertilizers.

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