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An Environmental Justice (EJ) analysis was carried out using full Chemical Transport Models (CTMs) over Los Angeles, California, to determine how the combination of domain size and spatial resolution affects predicted air pollution disparities in present day and future simulations when data support from measurements is not available. One set of simulations used the Weather Research and Forecasting (WRF) model coupled with Chemistry (WRF/Chem) with spatial resolution ranging from 250 m to 36 km, comparable to census tract sizes, over domains ranging in size from 320 km 2 to 10,000 km 2 . A second set of simulations used the UCD/CIT CTM with spatial resolution ranging from 4 km to 24 km over domains ranging in size from 98,000 km 2 to 1,000,000 km 2 . Overall WRF/Chem model accuracy improved approximately 9% as spatial resolution increased from 4 km to 250 m in present-day simulations, with similar results expected for future simulations. Exposure disparity results are consistent with previous findings: the average Non-Hispanic White person in the study domain experiences PM 2.5 mass concentrations 6-14% lower than the average resident, while the average Black and African American person experiences PM 2.5 mass concentrations that are 3-22% higher than the average resident. Predicted exposure disparities were a function of the model configuration. Increasing the spatial resolution finer than approximately 1 km produced diminishing returns because the increased spatial resolution came at the expense of reduced domain size in order to maintain reasonable computational burden. Increasing domain size to capture regional trends, such as wealthier populations living in coastal areas, identified larger exposure disparities but the benefits were limited. CTM configurations that use spatial resolution/domain size of 1 km/10 3 km 2 and 4 km/10 4 km 2 over Los Angeles can detect a 0.5 μg m -3 exposure difference with statistical power greater than 90%. These configurations represent a balanced approach between statistical power, sensitivity across socio-economic groups, and computational burden when predicting current and future air pollution exposure disparities in Los Angeles., Competing Interests: The authors declare no conflict of interest., (© 2022 Published by Elsevier Ltd.)

ER aminopeptidase 1 (ERAP1) is an intracellular enzyme that generates antigenic peptides and is an emerging target for cancer immunotherapy and the control of autoimmunity. ERAP1 inhibitors described previously target the active site and are limited in selectivity, minimizing their clinical potential. To address this, we targeted the regulatory site of ERAP1 using a high-throughput screen and discovered a small molecule hit that is highly selective for ERAP1. (4a R ,5 S ,6 R ,8 S ,8a R )-5-(2-(Furan-3-yl)ethyl)-8-hydroxy-5,6,8a-trimethyl-3,4,4a,5,6,7,8,8a-octahydronaphthalene-1-carboxylic acid is a natural product found in Dodonaea viscosa that constitutes a submicromolar, highly selective, and cell-active modulator of ERAP1. Although the compound activates hydrolysis of small model substrates, it is a competitive inhibitor for physiologically relevant longer peptides. Crystallographic analysis confirmed that the compound targets the regulatory site of the enzyme that normally binds the C-terminus of the peptide substrate. Our findings constitute a novel starting point for the development of selective ERAP1 modulators that have potential for further clinical development.

Objective: To obtain pilot data to evaluate the discriminatory power of biomarkers microRNA-122 (miR-122), high-mobility group box 1 (HMGB1), full-length keratin-18 (flk-18) and caspase-cleaved keratin-18 (cck-18) in plasma to identify potential biliary complications that may require acute intervention., Design: An observational biomarker cohort pilot study., Setting: In a Scottish University teaching hospital for 12 months beginning on 3 September 2014., Participants: Blood samples were collected from adults (≥16 years old) referred with acute biliary-type symptoms who have presented to hospital within 24 hours prior were recruited. Patients unable or refused to give informed consent or were transferred from a hospital outside the National Health Service regional trust were excluded., Primary Outcome Measures: To evaluate whether circulating miR-122, HMGB1, flk-18 and cck-18 can discriminate between people with and without gallstone disease and uncomplicated from complicated gallstone disease during the first 24 hours of hospital admission., Results: 300 patients were screened of which 285 patients were included. Plasma miR-122, cck-18 and flk-18 concentrations were increased in patients with gallstones compared with those without (miR-122: median: 2.89×10 4  copies/mL vs 0.90×10 4  copies/mL (p<0.001); cck-18: 121.2 U/L vs 103.5 U/L (p=0.031); flk-18: 252.4 U/L vs 145.1 U/L (p<0.001)). Uncomplicated gallstone disease was associated with higher miR-122 and cck-18 concentrations than complicated disease (miR-122: 5.72×10 4  copies/mL vs 2.26×10 4  copies/mL (p=0.023); cck-18: 139.7 U/L vs 113.6 U/L (p=0.047)). There was no significant difference in HMGB1 concentration between patients with and without gallstones (p=0.559). Separation between groups for all biomarkers was modest., Conclusion: miR-122 and keratin-18 plasma concentrations are elevated in patients with gallstones. However, this result is confounded by the association between biomarker concentrations, age and gender. In this pilot study, miR-122 and keratin-18 were not sufficiently discriminatory to be progressed as clinically useful biomarkers in this context., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

microRNA-122 (miR-122) is increasingly being measured in pre-clinical and clinical settings due to greater sensitivity and hepatic specificity compared to the gold standard liver injury biomarker alanine aminotransferase (ALT). In pre-clinical studies, various culling methods can be employed prior to collection of blood samples, including lethal injection with pentobarbital sodium (Pentoject). However, little is known about whether such an approach could alter the circulating levels of miR-122 and compromise the interpretation of data. We therefore exposed C57BL/6J mice to saline or the model hepatotoxin paracetamol and collected blood samples pre-cull ( via tail bleed) and post-cull ( via cardiac puncture following exposure to a rising concentration of CO 2 or intraperitoneal injection of Pentoject). Compared to pre-cull levels there was a significant increase in serum miR-122 level in mice culled with CO 2 and, to a much greater extent, in mice culled with Pentoject. As a result, whilst the serum level of miR-122 increased in Pentoject-culled animals exposed to paracetamol, the higher level in saline-treated mice rendered this difference statistically non-significant, in contrast to findings in animals culled with CO 2 . ALT levels were unaffected by sacrifice method. Consistent with the in vivo findings, exposure of primary mouse hepatocytes to Pentoject provoked a rapid and concentration-dependent release of miR-122 into the culture media. Thus, for optimal design and interpretation of data from pre-clinical liver injury studies in which miR-122 is to be used as a biomarker, we recommend that blood samples are collected pre-cull whenever possible, and that lethal injection with Pentoject is avoided.

Acetaminophen (APAP) overdoses are of major clinical concern. Growing evidence underlines a pathogenic contribution of sterile postinjury inflammation in APAP-induced acute liver injury (APAP-ALI) and justifies development of anti-inflammatory therapies with therapeutic efficacy beyond the therapeutic window of the only current treatment option, N-acetylcysteine (NAC). The inflammatory mediator, high mobility group box 1 (HMGB1), is a key regulator of a range of liver injury conditions and is elevated in clinical and preclinical APAP-ALI. The anti-HMGB1 antibody (m2G7) is therapeutically beneficial in multiple inflammatory conditions, and anti-HMGB1 polyclonal antibody treatment improves survival in a model of APAP-ALI. Herein, we developed and investigated the therapeutic efficacy of a partly humanized anti-HMGB1 monoclonal antibody (mAb; h2G7) and identified its mechanism of action in preclinical APAP-ALI. The mouse anti-HMGB1 mAb (m2G7) was partly humanized (h2G7) by merging variable domains of m2G7 with human antibody-Fc backbones. Effector function-deficient variants of h2G7 were assessed in comparison with h2G7 in vitro and in preclinical APAP-ALI. h2G7 retained identical antigen specificity and comparable affinity as m2G7. 2G7 treatments significantly attenuated APAP-induced serum elevations of alanine aminotransferase and microRNA-122 and completely abrogated markers of APAP-induced inflammation (tumor necrosis factor, monocyte chemoattractant protein 1, and chemokine [C-X-C motif] ligand 1) with prolonged therapeutic efficacy as compared to NAC. Removal of complement and/or Fc receptor binding did not affect h2G7 efficacy., Conclusion: This is the first report describing the generation of a partly humanized HMGB1-neutralizing antibody with validated therapeutic efficacy and with a prolonged therapeutic window, as compared to NAC, in APAP-ALI. The therapeutic effect was mediated by HMGB1 neutralization and attenuation of postinjury inflammation. These results represent important progress toward clinical implementation of HMGB1-specific therapy as a means to treat APAP-ALI and other inflammatory conditions. (Hepatology 2016;64:1699-1710)., (© 2016 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.)

Significance: High-mobility group box 1 (HMGB1) is a critical protein in the coordination of the inflammatory response in drug-induced liver injury (DILI). HMGB1 is released from necrotic hepatocytes and activated immune cells. The extracellular function of HMGB1 is dependent upon redox modification of cysteine residues that control chemoattractant and cytokine-inducing properties. Existing biomarkers of DILI such as alanine aminotransferase (ALT) have limitations such as lack of sensitivity and tissue specificity that can adversely affect clinical intervention., Recent Advances: HMGB1 isoforms have been shown to be more sensitive biomarkers than ALT for predicting DILI development and the requirement for liver transplant following acetaminophen (APAP) overdose. Hepatocyte-specific conditional knockout of HMGB1 has demonstrated the pivotal role of HMGB1 in DILI and liver disease. Tandem mass spectrometry (MS/MS) enables the characterization and quantification of different mechanism-dependent post-translationally modified isoforms of HMGB1., Critical Issues: HMGB1 shows great promise as a biomarker of DILI. However, current diagnostic assays are either too time-consuming to be clinically applicable (MS/MS) or are unable to distinguish between different redox and acetyl isoforms of HMGB1 (ELISA). Additionally, HMGB1 is not liver specific, so while it outperforms ALT (also not liver specific) as a biomarker for the prediction of DILI development, it should be used in a biomarker panel along with liver-specific markers such as miR-122., Future Directions: A point-of-care test for HMGB1 and the development of redox and acetyl isoform-targeting antibodies will advance clinical utility. Work is ongoing to validate baseline levels of circulating HMGB1 in healthy volunteers.

Restorative dentistry is experiencing a significant shift towards a rising usage of tougher all-ceramic materials. This trend must be incorporated into existing fixed prosthodontics academic curricula through the integration of lithium disilicate and zirconium oxide crown preparation guidelines. In addition, crown fabrication techniques have also evolved for these newer materials through digitization of preparations and impressions and their computer-assisted manufacturing. This article reviews current crown preparation and cementation guidelines while describing the teaching program in fixed prosthodontics at the University of Tennessee Health Sciences College of Dentistry.

Drug efflux pumps such as MexAB-OprM from Pseudomonas aeruginosa confer resistance to a wide range of chemically different compounds. Within the tripartite assembly, the inner membrane protein MexB is mainly responsible for substrate recognition. Recently, considerable advances have been made in elucidating the drug efflux pathway through the large periplasmic domains of resistance-nodulation-division (RND) transporters. However, little is known about the role of amino acids in other parts of the protein. We have investigated the role of two conserved phenylalanine residues that are aligned around the cytoplasmic side of the central cavity of MexB. The two conserved phenylalanine residues have been mutated to alanine residues (FAFA MexB). The interaction of the wild-type and mutant proteins with a variety of drugs from different classes was investigated by assays of cytotoxicity and drug transport. The FAFA mutation affected the efflux of compounds that have targets inside the cell, but antibiotics that act on cell wall synthesis and membrane probes were unaffected. Combined, our results indicate the presence of a hitherto unidentified cytoplasmic-binding site in RND drug transporters and enhance our understanding of the molecular mechanisms that govern drug resistance in Gram-negative pathogens., (© 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)