The ingestion of an elevated level (2%) of L-tryptophan (TRP) in a purified diet was investigated to determine whether it would influence the induction of gamma-glutamyltranspeptidase (GGT)-positive foci in the livers of rats exposed to a hepatocarcinogen. Subtotal hepatectomies were performed, and 18 h later, the rats were given injections i.p. of diethylnitrosamine (30 mg/kg). Ten days later,...

Isolated juvenile rainbow trout were fed a feed supplemented with L-tryptophan (TRP) for 3, 7 or 28 days, after which they were either sampled directly (undisturbed) or subjected to a standardised stressor prior to sampling. Controls (stressed and undisturbed) received the same feed but without any supplementary TRP. Stress resulted in a significant elevation of plasma [cortisol] in fish fed co...

AIMS We have previously suggested that acute ethanol consumption by normal subjects decreases the availability of circulating tryptophan (Trp) to the brain by activating liver Trp pyrrolase, the first and rate-limiting enzyme of the (major) kynurenine pathway of Trp degradation. The aim of the present study was to examine this hypothesis further by measuring plasma levels of kynurenine metaboli...

BACKGROUND As tumor antigen-specific CD4+ T cells can mediate strong therapeutic anti-tumor responses in melanoma patients we set out to establish a comprehensive screening strategy for the identification of tumor-specific CD4+ T cell epitopes suitable for detection, isolation and expansion of tumor-reactive T cells from patients. METHODS AND FINDINGS To scan the human melanoma differentiatio...

We hypothesized that the requirements of essential nutrients are dependent upon catabolic abilities. Mice lacking L-tryptophan 2,3-dioxygenase (TDO) are available. The body concentration of L-tryptophan (L-Trp) has been reported to be higher in TDO-deficient mice than in wild-type (WT) mice. We examined the requirement of an appropriate L-Trp level for TDO-deficient mice using several biomarker...

Two procedures for easily isolating deletions that fuse the trp and lac operons are described. Using these procedures, a large number of fusion deletions have been isolated. The 1a.c ends of these deletions extend varying distances into the &I gene and the Z&c promoter-operator region. Therefore, contrary to a previous report, there does not appear to be a messenger-termination signal at the Ct...

BACKGROUND Decreased circulating tryptophan (Trp) levels are frequently observed in elderly patients with neurodegenerative disease including Alzheimer's disease. Trp may serve as a potential biomarker for monitoring disease risk in elderly people. We aimed to investigate the association between low plasma Trp levels and olfactory function, which is known to predict age-related diseases includi...

Source rocks from a marine depositional setting from Palaeozoic formations in the Holy Cross Mountains region (Midlands, Poland) were analysed for aromatics using capillary gas chromatography±mass spectrometry (GC±MS). The occurrence of two novel series of aromatic hydrocarbons in these sediments, namely phenyl derivatives of fused ring polycyclic aromatic hydrocarbons (PhPAH) and polyphenyls (...

Serotonin (5-HT), a neurohormone with many physiological actions, is synthesized from the dietary essential amino acid tryptophan (TRP). However, the effects of TRP on neuronal ion transporters and its role in stress response have not yet been identified in the teleost fish. The effects of varied doses of TRP on the activities of mitochondrial (m) and cytosolic (c) ion transporters were examine...

The fungus Macrophomina phaseolina is a phytopathogen of great importance attacking various crops and causing severe losses especially in sorghum, beans, soybeans others. Since acetic indole acid (AIA) hormone that some authors associate with the pathogenic power other fungi such as Fusarium oxysporum, it was decided to perform this work detect whether M isolated from beans layers producing AIA...