Lead is a ubiquitous environmental contaminant; nearly 5% of American children are affected by lead poisoning (a blood lead level (BLL) of 10 mgdL 1 or higher). Even lower BLLs have been shown to cause many subtle health effects in children. Lead, which is found in paint and soil, causes toxicity by several possible mechanisms. Pb interacts with several zinc enzymes or proteins (such as carboni...

This study examined whether lead-induced alterations in selected parameters that are indicative of oxidative stress accompany the toxic effects of lead in red blood cells (RBCs) in vivo. It also explored the possibility that treatment with N-acetylcysteine (NAC) or succimer (meso-2,3-dimercaptosuccinic acid) was capable of reversing parameters indicative of lead-induced oxidative stress. Fisher...

We have evaluated and modified a current method for estimating 8-aminoIevulinic acid dehydratase (5-aminolaevulinate hydro-lyase, EC 4.2.1.24) activity in blood, so as to adequately control the pH of the enzyme-substrate solution at the optimum throughout the incubation period. This has improved the sensitivity and reliability of the assay. Also, N-ethylmaleimide has been substituted for a pote...

The enzyme delta-aminolevulinic acid dehydratase (ALAD), which catalyzes the second step of heme synthesis, can be inhibited by several chemicals, including lead, a potential risk factor for brain tumors, particularly meningioma. In this study we examined whether the ALAD G177C polymorphism in the gene coding for ALAD is associated with risk of intracranial tumors of the brain and nervous syste...

Lead is a ubiquitous environmental pollutant that poses serious health problems to humans, especially children. However, genetic variability in individuals varies their susceptibility lead poisoning. One possible factor polymorphism. Thus, this study aimed investigate the association between blood level (BLL), and polymorphisms delta-aminolevulinic acid dehydratase (ALAD) MspI (rs1800435) vitam...

Gabaculine and 4-amino-5-hexynoic acid (AHA) up to 3.0 millimolar concentration strongly inhibited 5-aminolevulinic acid (ALA) synthesis in developing cucumber (Cucumis sativus L. var Beit Alpha) chloroplasts, while they hardly affected protochlorophyllide (Pchlide) synthesis. Exogenous protoheme up to 1.0 micromolar had a similar effect. Exogenous glutathione also exhibited a strong inhibitory...

Glutamate was converted to the chlorophyll and heme precursor delta-aminolevulinic acid in soluble extracts of Euglena gracilis. delta-Aminolevulinic acid-forming activity depended on the presence of native enzyme, glutamate, ATP, Mg2+, NADPH or NADH, and RNA. The requirement for reduced pyridine nucleotide was observed only if, prior to incubation, the enzyme extract was filtered through activ...