91 research outputs found
Villából kórházat? A József Attiláról elnevezett kórház története
<p>Preoperative difficulty, expected and actual postoperative improvement on the Catquest-9SF items by functional characteristics (N = 174)<sup><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0169844#t004fn001" target="_blank">*</a></sup>.</p
MASNOVO, AMATO
To
address the poorly understood mixture effects of chemicals in
the marine mammal dugong, we coupled equilibrium-based passive sampling
in blubber to a range of in vitro bioassays for screening mixtures
of bioaccumulative chemicals. The modes of action included early effect
indicators along important toxicity pathways, such as induction of
xenobiotic metabolism, and some integrative indicators downstream
of the molecular initiating event, such as adaptive stress responses.
Activation of aryl hydrocarbon receptor (AhR) and Nrf2-mediated oxidative
stress response were found to be the most prominent effects, while
the p53-mediated DNA damage response and NF-κB-mediated response
to inflammation were not significantly affected. Although polychlorinated
dibenzo-<i>p</i>-dioxins (PCDDs) quantified in the samples
accounted for the majority of AhR-mediated activity, PCDDs explained
less than 5% of the total oxidative stress response, despite their
known ability to activate this pathway. Altered oxidative stress response
was observed with both individual chemicals and blubber extracts subject
to metabolic activation by rat liver S9 fraction. Metabolic activation
resulted in both enhanced and reduced toxicity, suggesting the relevance
and utility of incorporating metabolic enzymes into in vitro bioassays.
Our approach provides a first insight into the burden of toxicologically
relevant bioaccumulative chemical mixtures in dugongs and can be applied
to lipid tissue of other wildlife species
Evolution of Hepatic Glucose Metabolism: Liver-Specific Glucokinase Deficiency Explained by Parallel Loss of the Gene for Glucokinase Regulatory Protein (GCKR)
<div><p>Background</p><p>Glucokinase (GCK) plays an important role in the regulation of carbohydrate metabolism. In the liver, phosphorylation of glucose to glucose-6-phosphate by GCK is the first step for both glycolysis and glycogen synthesis. However, some vertebrate species are deficient in GCK activity in the liver, despite containing <i>GCK</i> genes that appear to be compatible with function in their genomes. Glucokinase regulatory protein (GCKR) is the most important post-transcriptional regulator of GCK in the liver; it participates in the modulation of GCK activity and location depending upon changes in glucose levels. In experimental models, loss of GCKR has been shown to associate with reduced hepatic GCK protein levels and activity.</p> <p>Methodology/Principal Findings</p><p><i>GCKR</i> genes and <i>GCKR</i>-like sequences were identified in the genomes of all vertebrate species with available genome sequences. The coding sequences of <i>GCKR</i> and <i>GCKR</i>-like genes were identified and aligned; base changes likely to disrupt coding potential or splicing were also identified.</p> <p>Conclusions/Significance</p><p><i>GCKR</i> genes could not be found in the genomes of 9 vertebrate species, including all birds. In addition, in multiple mammalian genomes, whereas <i>GCKR</i>-like gene sequences could be identified, these genes could not predict a functional protein. Vertebrate species that were previously reported to be deficient in hepatic GCK activity were found to have deleted (birds and lizard) or mutated (mammals) <i>GCKR</i> genes. Our results suggest that mutation of the <i>GCKR</i> gene leads to hepatic GCK deficiency due to the loss of the stabilizing effect of GCKR.</p> </div
Exons bearing inactivating mutation in mammalian <i>GCKR</i> genes.
<p>Exons bearing inactivating mutation in mammalian <i>GCKR</i> genes.</p
Bioenergy Potential from Food Waste in California
Food
waste makes up approximately 15% of municipal solid waste
generated in the United States, and 95% of food waste is ultimately
landfilled. Its bioavailable carbon and nutrient content makes it
a major contributor to landfill methane emissions, but also presents
an important opportunity for energy recovery. This paper presents
the first detailed analysis of monthly food waste generation in California
at a county level, and its potential contribution to the state’s
energy production. Scenarios that rely on excess capacity at existing
anaerobic digester (AD) and solid biomass combustion facilities, and
alternatives that allow for new facility construction, are developed
and modeled. Potential monthly electricity generation from the conversion
of gross food waste using a combination of AD and combustion varies
from 420 to 700 MW, averaging 530 MW. At least 66% of gross high moisture
solids and 23% of gross low moisture solids can be treated using existing
county infrastructure, and this fraction increases to 99% of high
moisture solids and 55% of low moisture solids if waste can be shipped
anywhere within the state. Biogas flaring practices at AD facilities
can reduce potential energy production by 10 to 40%
Genomic neighborhoods around vertebrate <i>GCKR</i> genes.
<p>Relative order and orientation of genes near the <i>GCKR</i> genes in human, chicken, Chinese softshell turtle, coelacanth, zebrafish and takifugu genomes. Gene names, as annotated in the human genome, are shown above the arrows, with the arrowhead indicating direction of transcription. Gene sizes and distance between genes are not to scale. Human is representative of the gene organization in mammals, while chicken is representative of birds. <i>GCKR</i> gene was not found in bird genomes. In fish, two distinct gene organizations were found – one found in zebrafish, and a second found in other fish genomes and represented by takifugu. The Chinese softshell turtle GCKR gene was distributed over two genomic contigs, with the slashes (/) indicating the ends of contigs.</p
Vertebrate <i>GCKR</i> genes.
*<p>Predicted genes have a single frame shift mutation that may be a sequencing error.</p
Evolution of <i>GCKR</i> genes and hepatic GCK activity in vertebrates.
<p>Summary of information on the structure of <i>GCKR</i> genes and hepatic GCK activity are placed on a phylogeny of vertebrates with available genome sequences (with the common names of the species shown on the right). Higher-level taxonomic groups of species are indicated to the right, with their composition indicated by the vertical bars. The phylogenetic relationship is from Ensembl (<a href="http://www.ensembl.org" target="_blank">www.ensembl.org</a>). <i>Xenopus laevis</i> is added to the tree as it has an intact <i>GCKR</i> cDNA. Genes are labeled as intact (I), likely intact (I?) or mutated (M), with the types of mutation indicated: fs = frame shift, sm = splice mutation, Δ = deletion, and Δ? = likely deletion (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060896#pone-0060896-t002" target="_blank">Tables 2</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060896#pone-0060896-t003" target="_blank">3</a>). The phylogenetic placement of gene inactivation events (Ψ, with type of inactivation indicated) was determined by parsimony. Possible inactivations, or events with unresolved locations (i.e., on the bird lineage), are indicated by the ? symbol. Hepatic GCK activity is from references 27-31, with Y = activity found, N = no or very low activity, and nd = not determined.</p
Relative rate tests.
1<p>– Number of unique amino acid substitutions on the lineages to species A and B when the Tasmanian devil sequence was used as the outgroup.</p>2<p>– Chi square value for the expectation that an equal number of substitutions occurred on each lineage.</p
Applicability of Passive Sampling to Bioanalytical Screening of Bioaccumulative Chemicals in Marine Wildlife
Quantification
of bioaccumulative contaminants in biota is time
and cost-intensive and the required extensive cleanup steps make it
selective toward targeted chemical groups. Therefore tissue extracts
prepared for chemical analysis are not amenable to assess the combined
effects of unresolved complex mixtures. Passive equilibrium sampling
with polydimethylsiloxane (PDMS) has the potential for unbiased sampling
of mixtures, and the PDMS extracts can be directly dosed into cell-based
bioassays. The passive sampling approach was tested by exposing PDMS
to lipid-rich tissue (dugong blubber; 85% lipid) spiked with a known
mixture of hydrophobic contaminants (five congeners of tetra- to octachloro-dibenzo-<i>p</i>-dioxins). The equilibrium was attained within 24 h. Lipid-PDMS
partition coefficients (<i>K</i><sub>lip‑PDMS</sub>) ranged from 20 to 38, were independent of hydrophobicity, and within
the range of those previously measured for organochlorine compounds.
To test if passive sampling can be combined with bioanalysis without
the need for chemical cleanup, spiked blubber-PDMS extracts were dosed
into the CAFLUX bioassay, which specifically targets dioxin-like chemicals.
Small quantities of lipids coextracted by the PDMS were found to affect
the kinetics in the regularly applied 24-h bioassay; however, this
effect was eliminated by a longer exposure period (72 h). The validated
method was applied to 11 unspiked dugong blubber samples with known
(native) dioxin concentrations. These results provide the first proof
of concept for linking passive sampling of lipid-rich tissue with
cell-based bioassays, and could be further extended to other lipid
rich species and a wider range of bioanalytical end points
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