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The aim of this work was to use phosphorus magnetic resonance spectroscopy (31P MRS) to investigate the pharmacodynamic effects of LAQ824, a histone deacetylase (HDAC) inhibitor. Human HT29 colon carcinoma cells were examined by 31P MRS after treatment with LAQ824 and another HDAC inhibitor, suberoylanilide hydroxamic acid. HT29 xenografts and tumor extracts were also examined using 31P MRS, pre- and post-LAQ824 treatment. Histone H3 acetylation was determined using Western blot analysis, and tumor microvessel density by immunohistochemical staining of CD31. Phosphocholine showed a significant increase in HT29 cells after treatment with LAQ824 and suberoylanilide hydroxamic acid. In vivo, the ratio of phosphomonoester/total phosphorus (TotP) signal was significantly increased in LAQ824-treated HT29 xenografts, and this ratio was inversely correlated with changes in tumor volume. Statistically significant decreases in intracellular pH, β-nucleoside triphosphate (β-NTP)/TotP, and β-NTP/inorganic phosphate (Pi) and an increase in Pi/TotP were also seen in LAQ824-treated tumors. Tumor extracts showed many significant metabolic changes after LAQ824 treatment, in parallel with increased histone acetylation and decreased microvessel density. Treatment with LAQ824 resulted in altered phospholipid metabolism and compromised tumor bioenergetics. The phosphocholine and phosphomonoester increases may have the potential to act as pharmacodynamic markers for noninvasively monitoring tumor response after treatment with LAQ824 or other HDAC inhibitors.

Endocrine-disrupting chemicals have the ability to interfere with and alter functions of the hormone system, leading to adverse effects on reproduction, growth and development. Despite growing concerns over their now ubiquitous presence in the environment, endocrine-related human health effects remain largely outside of comparative human toxicity characterization frameworks as applied for example in life cycle impact assessments. In this paper, we propose a new methodological framework to consistently integrate endocrine-related health effects into comparative human toxicity characterization. We present two quantitative and operational approaches for extrapolating towards a common point of departure from both in vivo and dosimetry-adjusted in vitro endocrine-related effect data and deriving effect factors as well as corresponding characterization factors for endocrine-active/endocrine-disrupting chemicals. Following the proposed approaches, we calculated effect factors for 323 chemicals, reflecting their endocrine potency, and related characterization factors for 157 chemicals, expressing their relative endocrine-related human toxicity potential. Developed effect and characterization factors are ready for use in the context of chemical prioritization and substitution as well as life cycle impact assessment and other comparative assessment frameworks. Endocrine-related effect factors were found comparable to existing effect factors for cancer and non-cancer effects, indicating that (1) the chemicals' endocrine potency is not necessarily higher or lower than other effect potencies and (2) using dosimetry-adjusted effect data to derive effect factors does not consistently overestimate the effect of potential endocrine disruptors. Calculated characterization factors span over 8-11 orders of magnitude for different substances and emission compartments and are dominated by the range in endocrine potencies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Screening certain environmental chemicals for their ability to interact with endocrine targets, including the androgen receptor (AR), is an important global concern. We previously developed a model using a battery of eleven in vitro AR assays to predict in vivo AR activity. Here we describe a revised mathematical modeling approach that also incorporates data from newly available assays and demonstrate that subsets of assays can provide close to the same level of predictivity. These subset models are evaluated against the full model using 1820 chemicals, as well as in vitro and in vivo reference chemicals from the literature. Agonist batteries of as few as six assays and antagonist batteries of as few as five assays can yield balanced accuracies of 95% or better relative to the full model. Balanced accuracy for predicting reference chemicals is 100%. An approach is outlined for researchers to develop their own subset batteries to accurately detect AR activity using assays that map to the pathway of key molecular and cellular events involved in chemical-mediated AR activation and transcriptional activity. This work indicates in vitro bioactivity and in silico predictions that map to the AR pathway could be used in an integrated approach to testing and assessment for identifying chemicals that interact directly with the mammalian AR., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The incidence of older adult traumatic brain injury (TBI) is increasing in both high and middle to low-income countries. It is unknown whether older adults with isolated, serious TBI can be safely managed outside of major trauma centres. This registry based cohort study aimed to compare mortality and functional outcomes of older adults with isolated, serious TBI who were managed at specialised Major Trauma Services (MTS) and Metropolitan Neurosurgical Services (MNS)., Method: Older adults (65 years and over) who sustained an isolated, serious TBI following a low fall (from standing or ≤ 1 m) were extracted from the Victorian State Trauma Registry from 2007 to 2016. Multivariable models were fitted to assess the association between hospital designation (MTS vs. MNS) and the two outcomes of interest: in-hospital mortality and functional outcome, adjusting for potential confounders. Functional outcomes were measured using the Glasgow Outcome Scale Extended at six months post-injury., Results: From 2007-2016, there were 1904 older adults who sustained an isolated, serious TBI from a low fall who received definitive care at an MTS (n = 1124) or an MNS (n = 780). After adjusting for confounders, there was no mortality benefit for patients managed at an MTS over an MNS (OR = 0.84; 95% CI: 0.65, 1.08; P = 0.17) or improvement in functional outcome six months post-injury (OR = 1.13; 95% CI: 0.94, 1.36; P = 0.21)., Conclusion: For older adults with isolated, serious TBI following a low fall, there was no difference in mortality or functional outcome based on definitive management at an MTS or an MNS. This confirms that MNS without the added designation of a major trauma centre are a suitable destination for the management of isolated, serious TBI in older adults., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Reviewing prehospital trauma deaths provides an opportunity to identify system improvements that may reduce trauma mortality. The objective of this study was to identify the number and rate of potentially preventable trauma deaths through expert panel reviews of prehospital and early in-hospital trauma deaths., Methods: We conducted a retrospective review of prehospital and early in-hospital (<24 h) trauma deaths following a traumatic out-of-hospital cardiac arrest that were attended by Ambulance Victoria (AV) in the state of Victoria, Australia, between 2008 and 2014. Expert panels were used to review cases that had resuscitation attempted by paramedics and underwent a full autopsy. Patients with a mechanism of hanging, drowning or those with anatomical injuries deemed to be unsurvivable were excluded., Results: Of the 1183 cases that underwent full autopsies, resuscitation was attempted by paramedics in 336 (28%) cases. Of these, 113 cases (34%) were deemed to have potentially survivable injuries and underwent expert panel review. There were 90 (80%) deaths that were not preventable, 19 (17%) potentially preventable deaths and 4 (3%) preventable deaths. Potentially preventable or preventable deaths represented 20% of those cases that underwent review and 7% of cases that had attempted resuscitation., Conclusions: The number of potentially preventable or preventable trauma deaths in the pre-hospital and early in-hospital resuscitation phase was low. Specific circumstances were identified in which the trauma system could be further improved., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The application of toxic equivalency factors (TEFs) or toxic units to estimate toxic potencies for mixtures of chemicals which contribute to a biological effect through a common mechanism is one approach for filling data gaps. Toxic Equivalents (TEQ) have been used to express the toxicity of dioxin-like compounds (i.e., dioxins, furans, and dioxin-like polychlorinated biphenyls (PCBs)) in terms of the most toxic form of dioxin: 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). This study sought to integrate two data gap filling techniques, quantitative structure-activity relationships (QSARs) and TEFs, to predict neurotoxicity TEQs for PCBs. Simon et al. (2007) previously derived neurotoxic equivalent (NEQ) values for a dataset of 87 PCB congeners, of which 83 congeners had experimental data. These data were taken from a set of four different studies measuring different effects related to neurotoxicity, each of which tested overlapping subsets of the 83 PCB congeners. The goals of the current study were to: (i) evaluate an alternative neurotoxic equivalent factor (NEF) derivations from an expanded dataset, relative to those derived by Simon et al. and (ii) develop QSAR models to provide NEF estimates for the large number of untested PCB congeners. The models used multiple linear regression, support vector regression, k-nearest neighbor and random forest algorithms within a 5-fold cross validation scheme and position-specific chlorine substitution patterns on the biphenyl scaffold as descriptors. Alternative NEF values were derived but the resulting QSAR models had relatively low predictivity (RMSE ∼0.24). This was mostly driven by the large uncertainties in the underlying data and NEF values. The derived NEFs and the QSAR predicted NEFs to fill data gaps should be applied with caution., (Published by Elsevier Inc.)

Research in toxicology generates vast quantities of data which reside on the Web and are subsequently appropriated and utilized to support further research. This data includes a broad spectrum of information about chemical, biological and radiological agents which can affect health, the nature of the effects, treatment, regulatory measures, and more. Information is structured in a variety of formats, including traditional databases, portals, prediction models, and decision making support tools. Online resources are created and housed by a variety of institutions, including libraries and government agencies. This paper focuses on three such institutions and the tools they offer to the public: the National Library of Medicine (NLM) and its Toxicology and Environmental Health Information Program, the United States Environmental Protection Agency (EPA), and the Organisation for Economic Co-operation and Development (OECD). Reference is also made to other relevant organizations., (Published by Elsevier Inc.)

Background: The aim of this study was to establish the profile and outcomes of paediatric major trauma care (PTMC) within an integrated inclusive regionalised trauma system., Methods: Prospectively collected data from July 2001 to June 2009 from the Victorian State Trauma Registry of patients aged <18 years were reviewed., Results: There were 1634 major trauma cases with a median (IQR) age of 13 (6-16) years and 69% were male. The median ISS (IQR) was 18 (16-26). There were 1361 patients treated at a major trauma centre of which 69% (n=943) were treated at the PMTC. Head injury (AIS>2) was the most frequent injury (n=950, 58%). Surgery was required in 39% (n=637) of all cases; 437 patients in the 10-17 year old group and 200 patients in the 0-9 year old group; the mortality was 6.6%. There were 530 patients (32.4%) ventilated in ICU; these had a median ISS (IQR) of 25 (17-34) and mortality of 7.4%. Improvements in risk-adjusted mortality have occurred as the years have progressed [adjusted OR 95% CI: 0.87 (0.76, 0.99)] and being treated at a Level 1 trauma centre was associated with lower adjusted odds of mortality [adjusted OR 95% CI: 0.27 (0.11, 0.68)]., Conclusion: The establishment of this integrated inclusive regionalised trauma system has been associated with progressively improving risk-adjusted mortality. The relatively low volume of major trauma requiring surgery in the 0-9 year old age group is notable, creating a challenging environment for maintaining skills and institutional preparedness., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The U.S. Environmental Protection Agency is developing chemical screening and prioritization programs to evaluate environmental chemicals for potential risk to human health in a rapid and efficient manner. As part of these efforts, it is important to catalog available information on chemical toxicity and exposure from widely dispersed sources. The main objective of this analysis is to define important aspects of the exposure space and to catalog the available exposure information for chemicals being considered for analysis as part of the U.S. EPA ToxCast™ screening and prioritization program. Publicly available exposure data have been extracted into ACToR (Aggregated Computational Toxicology Resource), which combines information for hundreds of thousands of chemicals from >600 public sources. We use data from ACToR to assess the exposure data landscape for environmental chemicals. Of the roughly 100,000 chemicals that have at least limited toxicity information available, less than one-fifth also have exposure information - and for most of these the information is of limited utility (e.g., production volume). Readily accessible data on concentrations in exposure-related media are only available for a much smaller fraction. Among these, the largest number of chemicals is measured in water with over 1150 unique compounds, followed by 788 substances measured in soil, and 670 in air. These small numbers clearly reflect a focus of resources on those substances previously identified as possibly posing a hazard to human health. Exposure to a much broader number of chemicals will need to be measured in order to fully realize the envisioned goal of using exposure information to guide toxicity testing., (Published by Elsevier B.V.)

The expression, regulation and function of mammalian Hippo pathway members in skeletal muscle is largely unknown. The aim of this study was thus to test the hypothesis that core members of the mammalian Hippo pathway are expressed in skeletal muscle and that the transcriptional co-factor Yap, a core member of the Hippo pathway, regulates C2C12 myogenesis. We found that the major components of the mammalian Hippo pathway including Yap are all expressed in skeletal muscles, C2C12 myoblasts and myotubes. In C2C12 myoblasts, Yap Ser127 phosphorylation is low and Yap localises to nuclei. Upon differentiation, Yap Ser127 phosphorylation increases approximately 20-fold and Yap translocates from the nucleus to the cytosol. To test whether the observed increase of Yap Ser127 phosphorylation is required for differentiation we overexpressed hYAP1 S127A, a mutant that can not be phosphorylated at Ser127, in C2C12 myoblasts. We found that overexpression of hYAP S127A prevented myotube formation, whereas the overexpression of wildtype hYAP1 or empty vector had no effect. In addition, more hYAP1 S127A overexpressing cells progressed through the S phase of the cell cycle and the expression of MRFs (myogenin, Myf5), Mef2c and cell cycle regulators (p21, cyclin D1) was significantly changed when compared to wildtype hYAP1 and empty vector overexpressing cells. This data suggests that the phosphorylation of Yap at Ser127 leads to a changed expression of MRFs and cell cycle regulators and is required for C2C12 myoblasts to differentiate into myotubes., (Copyright 2010 Elsevier Inc. All rights reserved.)

Three high-throughput screening (HTS) genotoxicity assays-GreenScreen HC GADD45a-GFP (Gentronix Ltd.), CellCiphr p53 (Cellumen Inc.) and CellSensor p53RE-bla (Invitrogen Corp.)-were used to analyze the collection of 320 predominantly pesticide active compounds being tested in Phase I of US. Environmental Protection Agency's ToxCast research project. Between 9% and 12% of compounds were positive for genotoxicity in the assays. However, results of the varied tests only partially overlapped, suggesting a strategy of combining data from a battery of assays. The HTS results were compared to mutagenicity (Ames) and animal tumorigenicity data. Overall, the HTS assays demonstrated low sensitivity for rodent tumorigens, likely due to: screening at a low concentration, coverage of selected genotoxic mechanisms, lack of metabolic activation and difficulty detecting non-genotoxic carcinogens. Conversely, HTS results demonstrated high specificity, >88%. Overall concordance of the HTS assays with tumorigenicity data was low, around 50% for all tumorigens, but increased to 74-78% (vs. 60% for Ames) for those compounds producing tumors in rodents at multiple sites and, thus, more likely genotoxic carcinogens. The aim of the present study was to evaluate the utility of HTS assays to identify potential genotoxicity hazard in the larger context of the ToxCast project, to aid prioritization of environmentally relevant chemicals for further testing and assessment of carcinogenicity risk to humans.

We have investigated the association between APOE genotypes and C-reactive protein (CRP) levels in a cohort of approximately 600 individuals who were candidates for statin therapy. An association had been previously reported between the APOE3 allele and elevated CRP levels. That study only examined men. We have reproduced that association in men and have extended the finding to women. We also investigated the effect of the interaction between APOE genotype and hormone replacement therapy (HRT) status on CRP levels, adjusting for body mass index (BMI) and other covariates. BMI and HRT are also significant predictors of CRP, as previously reported. The effect of HRT is strong enough that the contribution of APOE genotype is no longer statistically significant among women on HRT. We also demonstrate that the presence or absence of the single SNP Cysl30Arg (which distinguishes APOE4 from APOE2 and APOE3) is sufficient to determine whether an individual is predisposed to higher or lower CRP levels. Essentially, the presence of one or two copies of APOE4 is associated with a reduction of CRP levels by approximately 34% relative to individuals with zero copies (1.73 mg/L for subjects with one or two copies versus 2.63 mg/L for subjects with zero copies of APOE4). We also tested previously reported associations between CRP levels and polymorphisms in the CRP and IL6 genes. These associations were not reproduced in our cohort.

Objectives: The purpose of this study was to determine the prevalence and spectrum of nonsynonymous polymorphisms (amino acid variants) in the cardiac sodium channel among healthy subjects., Background: Pathogenic mutations in the cardiac sodium channel gene, SCN5A, cause approximately 15 to 20% of Brugada syndrome (BrS1), 5 to 10% of long QT syndrome (LQT3), and 2 to 5% of sudden infant death syndrome., Methods: Using single-stranded conformation polymorphism, denaturing high-performance liquid chromatography, and/or direct DNA sequencing, mutational analysis of the protein-encoding exons of SCN5A was performed on 829 unrelated, anonymous healthy subjects: 319 black, 295 white, 112 Asian, and 103 Hispanic., Results: In addition to the four known common polymorphisms (R34C, H558R, S1103Y, and R1193Q), four relatively ethnic-specific polymorphisms were identified: R481W, S524Y, P1090L, and V1951L. Overall, 39 distinct missense variants (28 novel) were elucidated. Nineteen variants (49%) were found only in the black cohort. Only seven variants (18%) localized to transmembrane-spanning domains. Four variants (F1293S, R1512W, and V1951L cited previously as BrS1-causing mutations and S1787N previously published as a possible LQT3-causing mutation) were identified in this healthy cohort., Conclusions: This study provides the first comprehensive determination of the prevalence and spectrum of cardiac sodium channel variants in healthy subjects from four distinct ethnic groups. This compendium of SCN5A variants is critical for proper interpretation of SCN5A genetic testing and provides an essential hit list of targets for future functional studies to determine whether or not any of these variants mediate genetic susceptibility for arrhythmias in the setting of either drugs or disease.