Simultaneous Measurement of Kynurenine and Tryptophan in Human Plasma and Supernatants of Cultured Human Cells by HPLC with Coulometric Detection

Abstract

host specificity. There thus is little danger that a laboratory worker could be infected (15 ). However, proper clinical laboratory safety precautions should be followed because the phage IACs represent genetically modified organisms. The presented protocol to generate phage IAC could be applied to any clinical PCR assay in which DNA from pathogens is detected. When phage IACs are added to clinical specimens before DNA extraction, all steps of the PCR assay, including lysis of pathogen particles, can be controlled.In addition, the presented approach might also be used for the generation of positive-control DNAs or DNA quantification standards for PCR assays. The resulting phage standards should be more stable than purified DNA and should exhibit improved handling and storage conditions compared with purified DNA standards for the clinical laboratory. For pathogen-specific PCR assays, the use of phage DNA standards could avoiding handling of infectious pathogenic standards possible.In conclusion, the generated phage IAC is one example of the application of lambda phage cloning for the generation of IACs for clinical PCR assays. The presented phage IAC, with its improved storage and handling properties, gave good results when used in our panel of real-time PCR assays and appears suitable for routine use; it also allows complete monitoring of PCR assays for sample adequacy.

Primary infection with simian immunodeficiency virus: plasmacytoid dendritic cell homing to lymph nodes, type I interferon, and immune suppression

“…34 The Kyn/Trp ratio was considered as an index of IDO activity, independent of baseline Trp concentrations. 35 …”

An Improved High Performance Liquid Chromatographic Method for Tryptophan Analysis in Rat Brain Administrated by Seaweed

“…The net consequence of this action is the reduction in TRP concentration in the body. This depletion in turn influences 5-HT production in brain and sends the patient into depression [33][34][35][36][37]. Therefore, TRP depletion is commonly used to recognize the susceptibility of patients towards depression [38,39].…”

Simultaneous determination of tryptophan and kynurenine in plasma samples of children patients with Kawasaki disease by high-performance liquid chromatography with programmed wavelength ultraviolet detection

“…The degradation of tryptophan takes place via two biochemical pathways: biosynthesis of the neurotransmitter serotonin and the kynurenine (Kyn) pathway [5,6]. Trp is the substrate for the first step in both of these pathways.…”

“…In the Kyn pathway which is the major catabolic route for Trp, the indole ring of Trp can be opened by the enzymes tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO), yielding N-formylkynurenine which is then converted to Kyn [6][7][8][9][10][11]. The reactions catalyzed by both of these enzymes constitute the rate-limiting step in the Kyn metabolic pathway [2,4,6]. Many studies showed that, like TDO, IDO is also a heme-containing enzyme, despite the fact that it shares no sequence homology with TDO [12].…”