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Miriam C. Poirier Stéphane Lair Robert Michaud Elena E. Hernández-Ramon Kathyayini V. Divi Jennifer E. Dwyer Corbin D. Ester Nancy N. Si Mehnaz Ali Lisa L. Loseto Stephen A. Raverty Judith A. St. Leger William G. Van Bonn Kathleen Colegrove Kathleen A. Burek-Huntington Robert Suydam Raphaela Stimmelmayr John Pierce Wise Sandra S. Wise Guy Beauchamp Daniel Martineau 《Environmental and molecular mutagenesis》2019,60(1):29-41
Carcinogenic polycyclic aromatic hydrocarbons (PAHs) were disposed directly into the Saguenay River of the St. Lawrence Estuary (SLE) by local aluminum smelters (Quebec, Canada) for 50 years (1926–1976). PAHs in the river sediments are likely etiologically related to gastrointestinal epithelial cancers observed in 7% of 156 mature (>19-year old) adult beluga found dead along the shorelines. Because DNA adduct formation provides a critical link between exposure and cancer induction, and because PAH–DNA adducts are chemically stable, we hypothesized that SLE beluga intestine would contain PAH–DNA adducts. Using an antiserum specific for DNA modified with several carcinogenic PAHs, we stained sections of paraffin-embedded intestine from 51 SLE beluga (0–63 years), 4 Cook Inlet (CI) Alaska beluga (0–26 years), and 20 beluga (0–46 years) living in Arctic areas (Eastern Beaufort Sea, Eastern Chukchi Sea, Point Lay Alaska) and aquaria, all with low PAH contamination. Stained sections showed nuclear light-to-dark pink color indicating the presence of PAH–DNA adducts concentrated in intestinal crypt epithelial lining cells. Scoring of whole tissue sections revealed higher values for the 51 SLE beluga, compared with the 20 Arctic and aquarium beluga (P = 0.003). The H-scoring system, applied to coded individual photomicrographs, confirmed that SLE beluga and CI beluga had levels of intestinal PAH–DNA adducts significantly higher than Arctic and aquarium beluga (P = 0.003 and 0.02, respectively). Furthermore, high levels of intestinal PAH–DNA adducts in four SLE beluga with gastrointestinal cancers, considered as a group, support a link of causality between PAH exposure and intestinal cancer in SLE beluga. Environ. Mol. Mutagen. 60:29–41, 2019. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
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Jesse Mez MD MS Daniel H. Daneshvar MD PhD Bobak Abdolmohammadi BA Alicia S. Chua MS Michael L. Alosco PhD Patrick T. Kiernan BA Laney Evers BA Laura Marshall BA Brett M. Martin MS Joseph N. Palmisano MS Christopher J. Nowinski PhD Ian Mahar PhD Jonathan D. Cherry PhD Victor E. Alvarez MD Brigid Dwyer MD Bertrand R. Huber MD PhD Thor D. Stein MD PhD Lee E. Goldstein MD PhD Douglas I. Katz MD Robert C. Cantu MD Rhoda Au PhD Neil W. Kowall MD Robert A. Stern PhD Michael D. McClean MS ScD Jennifer Weuve MPH ScD Yorghos Tripodis PhD Ann C. McKee MD 《Annals of neurology》2020,87(1):116-131
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Pat O’ Dwyer Vincent J. Cunnane 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2005,581(1):16-21
The facilitated transfer of silver, Ag+, has been studied at the Interface between Two Immiscible Electrolyte Solutions (ITIES). The transfer was achieved with the assistance of a calixarene-based silver ionophore. An investigation of the mechanistic details of the transfer was conducted using cyclic voltammetry at both micro and macro liquid|liquid interfaces. The mechanism was found to follow a Transfer by Interfacial Complexation (TIC)/Transfer by Organic phase Complexation (TOC) mechanism. The complex stoichiometry was found to shift from 1:1 to 1:2, metal:ligand, with increasing ionophore concentration. The logarithms of the complex association constants, , were estimated at 12.4 and 14.5, respectively. The charge transfer current was also found to be limited by diffusion of the transferring species and was unchanged by the presence of a range of interferents. The system thus shows promise for selective analytical applications. 相似文献
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Dental professionals are in an ideal position to recognize children at high nutritional and oral health risk and provide early intervention. Some of the children at highest risk for nutritional and oral health problems include those born prematurely, children with failure to thrive, those on multiple medications, special needs children with developmental delays, children with gastroesophageal reflux, and those with lactose intolerance. Nutrition and oral health guidelines are provided to aid the dental practitioner in providing preventive nutrition intervention to these high risk children. 相似文献
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