Iron is an essential growth factor for the proliferation and differentiation of all living cells in being centrally involved in oxygen transport by hemoglobin and myoglobin, in electron transport during mitochondrial respiration as being a part of complex I and II enzymes or in the regulation of transcription via its role as central component of ribonucelotid reductase (1,2). Moroever, iron pla...

In all of eight tested human cells and cell lines with inducible indoleamine 2,3-dioxygenase (EC 1.13.11.17) tetrahydrobiopterin biosynthesis was activated by interferon-gamma. This was demonstrated by GTP cyclohydrolase I (EC 3.5.4.16) activities and intracellular neopterin and biopterin concentrations. Pteridine synthesis was influenced by extracellular tryptophan. In T 24-cell extracts, subm...

background recurrent pregnancy loss (rpl) is a serious problem for pregnancy. there is evidence that vascular complications play a principal role in rpl. methylenetetrahydrofolate reductase (mthfr) is a key enzyme in folate metabolism. polymorphisms (c677t, a1298c) of mthfr gene are associated with decreased mthfr activity. objectives the aim of this study was to determine the association betwe...

A low molecular weight compound which stimulates the synthesis of porphyrinogens from PBG was isolated and purified from etiolated Euglena gracilis Z. Absorption and fluorescence excitation and emission spectra, as well as the molecular weight, revealed its structure as an unconjugated pteridine. FTIR bands and 'H NMR signals of the purified compound were identical with those of an authentic sa...