Navegando por Palavras-chave "drinking water"

Agora exibindo 1 - 2 de 2
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Exposure to arsenic at levels found in US drinking water modifies expression in the mouse lung
    (Oxford Univ Press, 2007-11-01) Andrew, Angeline S.; Bernardo, Viviane [UNIFESP]; Warnke, Linda A.; Davey, Jennifer C.; Hampton, Thomas; Mason, Rebecca A.; Thorpe, Jessica E.; Ihnat, Michael A.; Hamilton, Joshua W.; Dartmouth Med Sch; Dartmouth Coll; Universidade Federal de São Paulo (UNIFESP); Univ Oklahoma
    The mechanisms of action of drinking water arsenic in the lung and the threshold for biologic effects remain controversial. Our study utilizes Affymetrix 22,690 transcript oligonucleotide microarrays to assess the long-term effects of increasing doses of drinking water arsenic on expression levels in the mouse lung. Mice were exposed at levels commonly found in contaminated drinking water wells in the United States (0, 0.1, 1 ppb), as well as the 50 ppb former maximum contaminant level, for 5 weeks. the expression profiles revealed modification of a number of important signaling pathways, many with corroborating evidence of arsenic responsiveness. We observed statistically significant expression changes for transcripts involved in angiogenesis, lipid metabolism, oxygen transport, apoptosis, cell cycle, and immune response. Validation by reverse transcription-PCR and immunoblot assays confirmed expression changes for a subset of transcripts. These data identify arsenic-modified signaling pathways that will help guide investigations into mechanisms of arsenic's health effects and clarify the threshold for biologic effects and potential disease risk.
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Shiga toxin-producing Escherichia coli in drinking water supplies of north Parana State, Brazil
    (Wiley-Blackwell, 2013-04-01) Lascowski, K. M. S. [UNIFESP]; Guth, B. E. C. [UNIFESP]; Martins, F. H.; Rocha, S. P. D.; Irino, K.; Pelayo, J. S.; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Londrina (UEL); Adolfo Lutz Inst
    Aim To determine the occurrence and characteristics of Shiga toxin-producing Escherichia coli (STEC) in drinking water supplies treated and untreated. Methods and Results Drinking water samples (n=1850) were collected from 41 municipalities in the north of Parana State between February 2005 and January 2006. Escherichia coli isolates (n=300) were recovered from water and investigated for the presence of virulence markers related to STEC by PCR. STEC isolates recovered were then characterized for both phenotypic and genotypic traits. A total of 12 isolates (11 from untreated water and one from treated water) were positive for stx, including five positive for both stx1 and stx2, two positive for stx1 and five positive for stx2. None of the STEC isolates contained eae, but other virulence genes were observed such as ehxA (100%), saa (100%), lpfAO113 (75%), iha (42%), subAB (25%) and cdtV (8%). Multidrug resistance was identified in 25% of the STEC isolates. the 12 STEC isolates belonged to seven distinct serotypes and pulsed-field gel electrophoresis typing revealed the presence of two clusters and two clones in this region. Conclusion Drinking water, especially from untreated water supplies, can be source of STEC strains potentially pathogenic for humans. Significance and Impact of the Study the investigation of the drinking water supplies for pathogenic E.coli, as STEC, may be useful to prevent waterborne outbreaks.