(Pheo)melanin photosensitizes UVA-induced DNA damage in cultured human melanocytes

The question of whether melanins are photoprotecting and/or photosensitizing in human skin cells continues to be debated. To evaluate the role of melanin upon UVA irradiation, DNA single-strand breaks (ssb) were measured in human melanocytes differing only in the amount of pigment produced by culturing at two different concentrations, basic (0...

Effect of a vegan diet on biomarkers of chemoprevention in females

1. In order to study the potential beneficial effects of a vegan diet, a cross-sectional study was performed and several biomarkers of chemoprevention were measured in a population of female 'living food' eaters ('vegans'; n = 20) vs matched omnivorous controls (n = 20). 2. White blood cells obtained from fresh blood samples were subjected to...

Random amplified polymorphic DNA and restriction enzyme analysis of PCR amplified rDNA in taxonomy: Two identification techniques for food-borne yeasts

The random amplified polymorphic DNA (RAPD) assay and the restriction enzyme analysis of PCR amplified rDNA are compared for the identification of the common spoilage yeasts Zygosaccharomyces bailii, Z. rouxii, Saccharomyces cerevisiae, Candida valida and C. lipolytica. Both techniques proved to be adequate tools for yeast identification. Since...

Quantification of sulfur mustard-induced DNA interstrand cross-links and single-strand breaks in cultured human epidermal keratinocytes

The induction of DNA interstrand cross-links and their repair has been studied in cultured human epidermal keratinocytes exposed to sulfur mustard, bis-(β-chloroethyl)sulfide. Alkaline elution is the most sensitive method to determine the number of DNA interstrand cross-links quantitatively. However, in the case of sulfur mustard the reliability...

Detection of single-strand breaks and base damage in DNA of blood cells from leukaemia patients receiving chemo- and radiotherapy

Chemotherapy combined with total-body irradiation (TBI), a conditioning regimen for bone-marrow transplantation (BMT), causes lesions in the cellular DNA of the patients treated. To understand possible consequences of the DNA damage induced during such treatment, information is required about the nature of the damage, the level of induction and...

Quantitative detection of DNA damage in cells after exposure to ionizing radiation by means of an improved immunochemical assay

A simple, sensitive and fast immunochemical method has been developed to quantify the amount of DNA damage in cells of human blood after in vitro exposure to ionizing radiation. The technique is based on the enhancement of the radiation-induced single-strandedness, which occurs in DNA regions flanking strand breaks, by a controlled further...

Illusory DNA breaks in quiescent lymphocytes?

Gamma-ray induced double-strand breaks in DNA resulting from randomly-inflicted single-strand breaks: Temporal local denaturation, a new radiation phenomenon?

The induction of single- and double-strand breaks in DNA by γ-rays has been measured. The maximum number of nucleotide paris (a) between two independently induced single-strand breaks in opposite strands of the DNA which cannot prevent the occurrence of a double-strand break was found to amount to about 16. This value did not differ...