Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in -0

<p><b>Copyright information:</b></p><p>Taken from "Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in "</p><p>Environmental Health Perspectives 2004;112(17):1658-1664.</p><p>Published online 18 Aug 2004</p><p>PMCID:PMC1253655.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in -1

<p><b>Copyright information:</b></p><p>Taken from "Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in "</p><p>Environmental Health Perspectives 2004;112(17):1658-1664.</p><p>Published online 18 Aug 2004</p><p>PMCID:PMC1253655.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in -5

<p><b>Copyright information:</b></p><p>Taken from "Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in "</p><p>Environmental Health Perspectives 2004;112(17):1658-1664.</p><p>Published online 18 Aug 2004</p><p>PMCID:PMC1253655.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in -2

<p><b>Copyright information:</b></p><p>Taken from "Synergistic Embryotoxicity of Polycyclic Aromatic Hydrocarbon Aryl Hydrocarbon Receptor Agonists with Cytochrome P4501A Inhibitors in "</p><p>Environmental Health Perspectives 2004;112(17):1658-1664.</p><p>Published online 18 Aug 2004</p><p>PMCID:PMC1253655.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Selenium Ecotoxicology in Freshwater Lakes Receiving Coal Combustion Residual Effluents: A North Carolina Example

Anthropogenic activities resulting in releases of selenium-laden waste streams threaten freshwater ecosystems. Lake ecosystems demand special consideration because they are characterized by prolonged retention of selenium and continuous cycling of the element through the food chain, through which it becomes available to toxicologically susceptible egg-laying vertebrates. This study documents the current selenium burden of lakes in North Carolina (NC) with historic selenium inputs from nearby coal-fired power plants. We measured selenium concentrations in surface waters, sediment pore waters, and resident fish species from coal combustion residual (CCR)-impacted lakes and paired reference lakes. The data are related to levels of recent selenium inputs and analyzed in the context of recently updated federal criteria for the protection of aquatic life. We show that the Se content of fish from lakes with the highest selenium inputs regularly exceed these criteria and are comparable to those measured during historic fish extirpation events in the United States. Large legacy depositions of CCRs within reservoir sediments are likely to sustain Se toxicity for many years despite recent laws to limit CCR discharge into surface waters in NC. Importantly, the widespread use of high-selenium coals for electricity generation extends the potential risk for aquatic ecosystem impacts beyond U.S. borders

High-Throughput Tissue Bioenergetics Analysis Reveals Identical Metabolic Allometric Scaling for Teleost Hearts and Whole Organisms

<div><p>Organismal metabolic rate, a fundamental metric in biology, demonstrates an allometric scaling relationship with body size. Fractal-like vascular distribution networks of biological systems are proposed to underlie metabolic rate allometric scaling laws from individual organisms to cells, mitochondria, and enzymes. Tissue-specific metabolic scaling is notably absent from this paradigm. In the current study, metabolic scaling relationships of hearts and brains with body size were examined by improving on a high-throughput whole-organ oxygen consumption rate (OCR) analysis method in five biomedically and environmentally relevant teleost model species. Tissue-specific metabolic scaling was compared with organismal routine metabolism (RMO₂), which was measured using whole organismal respirometry. Basal heart OCR and organismal RMO₂ scaled identically with body mass in a species-specific fashion across all five species tested. However, organismal maximum metabolic rates (MMO₂) and pharmacologically-induced maximum cardiac metabolic rates in zebrafish <i>Danio rerio</i> did not show a similar relationship with body mass. Brain metabolic rates did not scale with body size. The identical allometric scaling of heart and organismal metabolic rates with body size suggests that hearts, the power generator of an organism’s vascular distribution network, might be crucial in determining teleost metabolic rate scaling under routine conditions. Furthermore, these findings indicate the possibility of measuring heart OCR utilizing the high-throughput approach presented here as a proxy for organismal metabolic rate—a useful metric in characterizing organismal fitness. In addition to heart and brain OCR, the current approach was also used to measure whole liver OCR, partition cardiac mitochondrial bioenergetic parameters using pharmacological agents, and estimate heart and brain glycolytic rates. This high-throughput whole-organ bioenergetic analysis method has important applications in toxicology, evolutionary physiology, and biomedical sciences, particularly in the context of investigating pathogenesis of mitochondrial diseases.</p></div

Slopes (exponent <i>b</i>) and <i>R</i>^<i>2</i> values for log oxygen consumption rates of whole organisms, hearts and brains <i>vs</i> log body mass for all five species combined and for each individual species¹.

<p>¹See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0137710#pone.0137710.s006" target="_blank">S3 Table</a> for Y intercept values, 95% confidence intervals and sample sizes.</p><p>^aExponent <i>b</i> for hearts or brains are statistically similar (<i>P>0</i>.<i>05</i>) to that of whole organisms (<i>F (DFn</i>, <i>DFd</i>) and <i>P</i> values are in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0137710#pone.0137710.s007" target="_blank">S4 Table</a>).</p><p>Slopes (exponent <i>b</i>) and <i>R</i>^<i>2</i> values for log oxygen consumption rates of whole organisms, hearts and brains <i>vs</i> log body mass for all five species combined and for each individual species<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0137710#t002fn001" target="_blank">¹</a>.</p

Slopes and Y intercepts for log₁₀ oxygen consumption rates for hearts plotted against log₁₀ heart mass for all five species and for each <i>Danio rerio and Fundulus heteroclitus</i>.

<p>^aTotal number of fish tested is obtained by combining number of samples in analyzed and outliers rows.</p><p>Slopes and Y intercepts for log₁₀ oxygen consumption rates for hearts plotted against log₁₀ heart mass for all five species and for each <i>Danio rerio and Fundulus heteroclitus</i>.</p

Metabolic profiles of <i>Danio rerio</i> heart and brain tissues.

<p>Oxygen consumption rate (OCR) calculated per gram of tissues is plotted against extracellular acidification rates (ECAR) <i>(n = 5)</i>. Measurements recorded in un-buffered solution are shown in square symbols and triangles represent values post-injection of buffering components of the Ringer’s solution. Values are expressed as means ± S.E.M.</p

Metabolic partitioning of <i>Danio rerio</i> and <i>Fundulus heteroclitus</i> heart tissue oxygen consumption rate (OCR).

<p>(a) Conceptual diagram depicting use of FCCP and antimycin A + rotenone and the metabolic parameters calculated from changes in oxygen consumption. (b) OCR following exposure to FCCP and antimycin A + rotenone (Ant + Rot). (c) Total OCR due to mitochondrial respiration, total mitochondrial capacity and mitochondrial reserve capacity calculated based on FCCP and antimycin A + rotenone. ‘a’ denotes statistical significance compared to <i>D</i>. <i>rerio</i> basal heart OCR and ‘b’ denotes statistical significance compared to <i>F</i>. <i>heteroclitus</i> basal heart OCR. Statistical significance between <i>D</i>. <i>rerio</i> and <i>F</i>. <i>heteroclitus</i> for a given measurement is denoted by * (Two-Way ANOVA followed by Tukey’s post-hoc test to correct for multiple comparisons; <i>P<0</i>.<i>05</i>). Values are expressed as means ± S.E.M.</p