Publications by authors named "C Helmschrodt"

The sensitive and simultaneous measurement of multiple neurotransmitters in microdialysate (MD) of freely moving mice is a prerequisite to study neurochemical imbalances in specific brain regions. The quantitative analysis of 16 neurotransmitters and metabolites, including serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), melatonin (ME), dopamine (DA), levodopa (l-DOPA), 3-methoxytyramine (3-MT), norepinephrine (NE), epinephrine (EP), homovanillinic acid (HVA), acetylcholine (ACh), deoxy carnitine (iso-ACh), choline (Ch), and ɣ-aminobutyric acid (GABA), adenosine (ADE), glutamine (Gln), and glutamic acid (Glu) was achieved within a chromatographic separation time of 6.5 min by the application of a biphenyl column coupled to an API-QTrap 5500 (AB SCIEX) mass spectrometer.

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The continuous measurement of multiple neurotransmitters in microdialysate of freely moving mice to study neurochemical changes in specific brain regions requires a rapid and very sensitive quantitative analytical method. The quantitative analysis of 11 neurotransmitters and metabolites, including serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), melatonin (ME), dopamine (DA), levodopa (L-DOPA), 3-methoxytyramine (3-MT), norepinephrine (NE), epinephrine (EP), acetylcholine (ACh), choline (Ch), and γ-aminobutyric acid (GABA), was performed using a biphenyl column coupled to an API-QTrap 3200 (AB SCIEX) mass spectrometer in positive electrospray ionization mode. To the microdialysate samples, 0.

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Background And Aims: Circulating sterols result either from cholesterol (CH) synthesis or intestinal uptake. They are mainly esterified and can be oxygenated. Sterols accumulate in atherosclerotic plaques whereby their clinical impact is uncertain.

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In early-onset generalized torsion dystonia, caused by a GAG deletion in TOR1A (DYT1), enhanced striatal cholinergic activity has been suggested to be critically involved. Previous studies have shown increased acetylcholine levels in the striatum of DYT1 knock-in (KI) mice. Ex vivo data indicated that muscarinic receptor antagonists normalize the activity of striatal cholinergic interneurons.

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This Research Communication describes the residue concentration of a dry cow antibiotic in two different milk fractions and describes effects of milk fraction and milk composition on the test performance of a rapid screening and a microbial inhibitor test. Thirteen dry cows were treated with an intramammary dry cow antibiotic containing 150 mg cefquinome. Quarter foremilk and stripping samples were collected on the first 10 d postpartum.

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