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Showing 1 to 17 of 17 for “"Pteridines."”.
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Capillary electrophoresis of pteridines in urine and plants and quantification of pharmaceutical and personal care products in Missouri waste water
… matrices. The first project investigated pteridines in urine and plants. The second project investigated pharmaceutical and personal care products (PPCP's) in Missouri waste water.</p> <p>As cancer continues to be one of the top three causes of human fatalities, early cancer screening …
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Synthesis of pyrrolo[2,3-d]pyrimidines and pyrazino[2,3-d]pyrimidines and their biological activities
… by reaction in neat amine. 6,7-Functionalised pteridines were prepared by the Isay cyclocondensation. The thiobenzyl group at C4 of prepared pteridines was effectively displaced by five different amines without an oxidation step. Microwave assisted reaction reduced the reaction times and …
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Biomarker discovery using urinary metabolomics for noninvasive early cancer detection
… status and time since last urination. Briefly, pteridines and their derivatives function as intermediates in the metabolism of various vitamins and cofactors, where altered levels of pteridines have been reported in the urine of patients with several types of epithelial cancers, among other …
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Mechanisms of Pteridine-Ommochrome Interactions in Drosophila Melanogaster
Ommochromes (brown pigments) and certain pteridines (red pigments), contribute to the typical reddish-brown eye color of wild-type Drosophila melanogaster. Each pigment is the end product of a seemingly unrelated metabolic pathway (Ziegler 1961; Kaufman 1967a). Mutations which alter the synthesis …
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A new catoptric system in the eyes of penaeid shrimp
… cholesterol (Nicol and Attaway, unpublished) and pteridines (Nicol and Van Baalen, unpublished) to be present in shrimp eyes. Further study indicated that pteridines are the probable chemical constituents of the tapeta.
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The synthesis and application of tetrahydrobiopterin mimetics
… which fell under the category of blocked dihydropteridines. One of the main aims of this PhD was to synthesise and assess various analogues of WSG1002, primarily for their NOS-activating properties. This work was carried out, not only in the hope of discovering a pteridine or related compound …
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ESTABLISHING PTERIDINE METABOLISM IN A BREAST CANCER CELL MODEL AND QUANTIFICATION OF SILVER NANOPARTICLE INTERACTIONS WITH YEAST CELLS USING MASS SPECTROMETRY
… dosing cell cultures with folic acid and 15 pteridines. Eight potential pteridine biomarkers in breast cancer cells were identified including pterin and isoxanthopterin, which yielded the first in vitro evidence for the cellular metabolisms behind previously reported elevated urinary …
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Tetrahydrobiopterin Metabolism in Mental Retardation
… ‘conditions for the separation and detection of pteridines by high performance liquid chromatography (HPLC) were obtained. The retention time, reproducibility relative fluorescence and minimal detection limits of various pterins under fixed conditions was noted. The stability of pterins under …
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The Fate of Folic Acid and Related Compounds in the Rat
… formed during isolation. Labelled unconjugated pteridines were absent. Six hours after administration of pteroyl-L-glutamic acid, more than seven labelled compounds were isolated from liver homogenates. Extractions performed up to 10 days after administration or after prior starvation only …
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Isolation and Identification of the Abnormal Opaque material in the White Mutant of Siamese Fighting Fish, Betta Splendens
… in that purines increase in chromatophores when pteridines decrease. This may be either an enzymatic or hormonal disorder of the chromatophore. Enzymic and hormonal analyses should be done on the Op Bettas. Several genetic crosses are also needed with subsequent pigment, enzyme, and hormone …
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Studies in the handling and absorption of biopterin derivatives in man
… which affect it assessed, The effects of various pteridines on the assay demonstrated sufficient specificity to allow qualitative deductions from results. Reproducibility and recovery experiments confirmed that it was usable for quantitative analysis, The narrow range of Crithidia active pterins …
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Aspects of Folate and Tetrahydrofolate Chemistry and Metabolism in the Rat
… metabolised; it gave a large amount of excreted pteridines, not observed with the other compounds, It inhibited folic acid metabolism in humans, but was ineffective as a growth inhibitor of R1 lymphoma in mice. Folic acid -(2-14C) given to tumour-bearing animals was metabolised more than in …
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The methylation of aminopteridines and aminopyrimidines
… describes the methylation of a number of aminopteridines and aminopyrimidines. In actual fact however, it consists of much more than an investigation of one type of reaction, since emphasis has been placed upon the chemistry of the methylation products and the manner in which they can be …
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The methylation of aminopteridines and aminopyrimidines
… describes the methylation of a number of aminopteridines and aminopyrimidines. In actual fact however, it consists of much more than an investigation of one type of reaction, since emphasis has been placed upon the chemistry of the methylation products and the manner in which they can be …
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Bacterial Cyanide Assimilation: Pterin Cofactor and Enzymatic Requirements for Substrate Oxidation
Utilization of cyanide as the sole nitrogen source by Pseudomonas fluorescens NCIMB 11764 (Pf11764) occurs via oxidative conversion to carbon dioxide and ammonia, the latter satisfying the nitrogen requirement. Substrate attack is initiated oxygenolytically by an enzyme referred to as cyanide …