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  • Trace metals and over-expression of metallothioneins in bladder tumoral lesions: a case-control study
    Publication . Amaral, André; Cymbron, Teresa; Gärtner, Fátima; Lima, Manuela; Rodrigues, Armindo
    Background: Previous studies have provided some evidence of a possible association between cancer and metallothioneins. Whether this relates to an exposure to carcinogenic metals remains unclear. Methods: In order to examine the association between the expression of metallothioneins and bladder tumors, and to compare the levels of arsenic, cadmium, chromium, lead and nickel in animals with bladder tumors and animals without bladder tumors, 37 cases of bovine bladder tumors and 17 controls were collected. The detection and quantification of metallothioneins in bladder tissue of both cases and controls was performed by immunohistochemistry. And the quantification of metals in tissue and hair was assessed by inductively coupled plasma – mass spectrometry. Results: Increased expression of metallothioneins was associated with bladder tumors when compared with non-tumoral bladder tissue (OR = 9.3, 95% CI: 1.0 – 480). The concentrations of cadmium, chromium, lead and nickel in hair of cases were significantly higher than those of controls. However, as for the concentration of metals in bladder tissue, the differences were not significant. Conclusion: Though the sample size was small, the present study shows an association between bladder tumors and metallothioneins. Moreover, it shows that concentrations of metals such as cadmium, chromium, lead and nickel in hair may be used as a biomarker of exposure.
    2009-07-18Journal article Open access Show more
  • The red algal genus Titanophora (Schizymeniaceae, Nemastomatales) in the Gulf of Mexico
    Publication . Gabriel, Daniela; Fredericq, Suzanne
    ABSTRACT: "Titanophora (J. Agardh) Feldmann currently comprises nine species inhabiting tropical and subtropical waters worldwide. The genus is distinguished from other members of the Schizymeniaceae primarily by the calcification of the frond and the presence of an involucre surrounding the carposporophyte. The present study provides a characterization of four distinct Titanophora species that were dredged throughout the Gulf of Mexico. On the basis of comparative vegetative and reproductive morphology and chloroplast-encoded rbcL sequence analysis, a new record for the Gulf, T. submarina Bucher & J.N. Norris, and two species new to science in addition to T. incrustans (J. Agardh) Boergesen are recognized for the region."
    2009-07-18Conference object Open access Show more
  • New insights in the systematics of Peyssonnelia and the Peyssonneliaceae (Rhodophyta), with emphasis on taxa from the Gulf of Mexico and Panama
    Publication . Krayesky, David; Norris, James N.; Gabrielson, Paul W.; Gabriel, Daniela; Fredericq, Suzanne
    ABSTRACT: "Peyssonnelia Decaisne comprises a worldwide group of non-calcified or calcified, crust-forming red algae of great ecological significance, with some species involved in the establishment of rhodoliths. Of the eight genera currently recognized in the family, Peyssonnelia, is widely viewed to contain the largest number of species. The number of distinct species of Peyssonneliaceae present in the Gulf of Mexico has increased from 6 to 21. Comparative morphology, chloroplast-encoded rbcL and nuclear LSU rDNA sequence data suggest that species of Peyssonnelia do not occur in the Gulf of Mexico, and that previously reported Peyssonnelia species for the region actually belong to other genera of the Peyssonneliales." (a) University of Louisiana at Lafayette (b) Smithsonian Institution (c) University of North Carolina
    2009-07-18Journal article Open access Show more