PubMed Health⌕ Search

Biomedical subjects

Dagmar Lampe

Publications and source records attributed to Dagmar Lampe.

3 recordsLinked to original sources

New screening method for basic compounds in urine by on-line extraction-high-performance liquid chromatography with photodiode-array detection.

A fully automated, qualitative screening HPLC method for the identification of basic compounds in urine has been developed. A 1-ml volume of urine was extracted by on-line extraction and separated on two coupled strong cation-exchange (SCX) columns (2 x LunaSCX, 150 mm x 4.6 mm, 5 microm) under isocratic conditions. The mobile phase consisted of a mixture of potassium dihydrogenphosphate buffer (pH 2.3) and acetonitrile. The use of photodiode-array detection (DAD, lambda = 190-800 nm) gave access to a library of approximately 2600 toxicologically relevant compounds. The validated method is reliable, simple and in addition successfully proven with the analysis of real biological specimen for the routine use.

Alkaloids↗

Itraconazole prophylaxis in pediatric cancer patients receiving conventional chemotherapy or autologous stem cell transplants.

GOAL OF WORK: During the renovation works at our institution, the incidence density for invasive aspergillosis (IA) increased from <0.5 to 0.99/1,000 inpatient days in 2001. As a direct response to this increased environmental risk, itraconazole (ITC) was administered for primary prophylaxis in pediatric cancer patients for whom a particular high risk of IA was anticipated due to prolonged severe neutropenia (>10 days), autologous stem cell transplantation, acute myeloblastic leukemia or relapsed acute lymphoblastic leukemia, or high-dose steroids >3 weeks. MATERIALS AND METHODS: In this open-label, prospective observational study, ITC was given in ITC solution or capsule. Trough concentrations were measured in plasma with high-performance liquid chromatography after at least 7 days of treatment. Doses were adjusted to target plasma trough ITC concentrations > or =0.5 mg/l. RESULTS: From 2001 to 2005, 39 pediatric cancer patients received 44 prophylactic ITC cycles; 102 trough plasma concentrations were measured after oral administration. Plasma target concentrations >0.5 mg/l were achieved with both formulations. A median dose of 8 mg kg(-1) day(-1) (3.5-16.0 mg kg(-1) day(-1)) was necessary in pediatric oncology patients. The bioavailability of the liquid formulation was significantly lower when the solution was given by a feeding tube. Adverse effects (gastrointestinal, elevated transaminases, and one hemolysis) which led to the cessation of the ITC prophylaxis were reported in 11% of all courses. No breakthrough infection was seen in this pediatric population. CONCLUSION: Oral ITC offers a feasible and inexpensive option for antifungal prophylaxis in selected pediatric cancer patients. Drug monitoring and meticulous consideration of possible interactions and adverse effects are mandatory.

Antifungal Agents↗

Acute bromadiolone intoxication.

A 55-year-old man came to the hospital with a bleeding wound on his tongue. The coating of his tongue was green, and his sputum was red. Because an increased international normalized ratio-value was measured, a blood sample was sent to our laboratory with the suspicion of coumarin intoxication. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analysis confirmed the poisoning was by bromadiolone, with its maximum serum concentration at 440 microg/L. The analysis of further samples resulted in a calculated elimination half-life of 140 h. The analytical method described was developed for the determination and quantitation of bromadialone using LC-MS. This method is suitable for the simultaneous identification and quantitation of 10 indirect anticoagulants in human serum, which include five superwarfarins (brodifacoum, bromadiolone, difenacoum, difethialone, and flocoumafen) as rodenticides licenced in Germany and five other vitamin K antagonists (acenocoumarol, coumatetralyl, coumachlor, phenprocoumon, and warfarin). The method is based on an acidic (pH 4.2) liquid-liquid extraction followed by LC-ESI-MS analysis. Analytical separation was carried out using an Atlantis C18 column (2.1 x 20 mm, 3 microm). The mobile phase consisted of methanol/0.1% formic acid; the flow rate was 0.6 mL/min, and the time needed for analysis was 5 min. The lower limit of quantitation was 5 microg/L (signal-to-noise > 10).

4-Hydroxycoumarins↗