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The breakdown product of the rubber tire antioxidant N‐(1,3‐dimethylbutyl)‐N'‐phenyl‐p‐phenylenediamine‐quinone (6PPD)‐6‐PPD‐quinone has been strongly implicated in toxic injury and death in coho salmon (Oncorhynchus kisutch) in urban waterways. Whereas recent studies have reported a wide range of sensitivity to 6PPD‐quinone in several fish species, little is known about the risks to Chinook salmon (Oncorhynchus tshawytscha), the primary prey of endangered Southern Resident killer whales (Orcinus orca) and the subject of much concern. Chinook face numerous conservation threats in Canada and the United States, with many populations assessed as either endangered or threatened. We evaluated the acute toxicity of 6PPD‐quinone to newly feeding (~3 weeks post swim‐up) juvenile Chinook and coho. Juvenile Chinook and coho were exposed for 24 h under static conditions to five concentrations of 6PPD‐quinone. Juvenile coho were 3 orders of magnitude more sensitive to 6PPD‐quinone compared with juvenile Chinook, with 24‐h median lethal concentration (LC50) estimates of 41.0 and more than 67 307 ng/L, respectively. The coho LC50 was 2.3‐fold lower than what was previously reported for 1+‐year‐old coho (95 ng/L), highlighting the value of evaluating age‐related differences in sensitivity to this toxic tire‐related chemical. Both fish species exhibited typical 6PPD‐quinone symptomology (gasping, increased ventilation, loss of equilibrium, erratic swimming), with fish that were symptomatic generally exhibiting mortality. The LC50 values derived from our study for coho are below concentrations that have been measured in salmon‐bearing waterways, suggesting the potential for population‐level consequences in urban waters. The higher relative LC50 values for Chinook compared with coho merits further investigation, including for the potential for population‐relevant sublethal effects. Environ Toxicol Chem 2023;42:815–822. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Fisheries and Oceans Canada. [ABSTRACT FROM AUTHOR]

Objective: To explore differences in position emission tomography-computed tomography (PET-CT) service provision internationally to further understand the impact variation may have upon cancer services. To identify areas of further exploration for researchers and policymakers to optimize PET-CT services and improve the quality of cancer services.Design: Comparative analysis using data based on pre-defined PET-CT service metrics from PET-CT stakeholders across seven countries. This was further informed via document analysis of clinical indication guidance and expert consensus through round-table discussions of relevant PET-CT stakeholders. Descriptive comparative analyses were produced on use, capacity and indication guidance for PET-CT services between jurisdictions.Setting: PET-CT services across 21 jurisdictions in seven countries (Australia, Denmark, Canada, Ireland, New Zealand, Norway and the UK).Participants: None.Intervention(s): None.Main Outcome Measure(s): None.Results: PET-CT service provision has grown over the period 2006-2017, but scale of increase in capacity and demand is variable. Clinical indication guidance varied across countries, particularly for small-cell lung cancer staging and the specific acknowledgement of gastric cancer within oesophagogastric cancers. There is limited and inconsistent data capture, coding, accessibility and availability of PET-CT activity across countries studied.Conclusions: Variation in PET-CT scanner quantity, acquisition over time and guidance upon use exists internationally. There is a lack of routinely captured and accessible PET-CT data across the International Cancer Benchmarking Partnership countries due to inconsistent data definitions, data linkage issues, uncertain coverage of data and lack of specific coding. This is a barrier in improving the quality of PET-CT services globally. There needs to be greater, richer data capture of diagnostic and staging tools to facilitate learning of best practice and optimize cancer services. [ABSTRACT FROM AUTHOR]

Domoic acid, a phycotoxin produced by species of the marine diatom Pseudo-nitzschia, can cause deleterious impacts to marine food webs and human health. Domoic acid and Pseudo-nitzschia spp. were surveyed from 2016 to 2021 in the Pacific waters of Canada to assess their occurrences, concentrations, and relationships with physical and chemical conditions. Domoic acid was common, occurring in measurable concentrations in 73 % of the 454 samples. It occurred in all regions (west coast of Vancouver Island, Salish Sea, Queen Charlotte Sound / Hecate Strait, deep oceanic NE Pacific), in all years and all seasons. Median concentrations were highest along the west coast of Vancouver Island, and lowest in the oceanic waters of the NE Pacific. Winter had the lowest concentrations; no significant differences occurred between spring, summer, and autumn. High domoic acid concentrations equal to or above 100 ng/L were not common, occurring in about 5 % of samples, but in all seasons and all years except 2019. All six Pseudo-nitzschia taxa identified had similar median concentrations, but different frequencies of occurrence. P. cf. australis appeared to be the major contributor to high concentrations of domoic acid. Physico-chemical conditions were described by ten variables: temperature, salinity, density difference between 30 m and the surface (a proxy for vertical stability), chlorophyll a, nitrate, phosphate, silicate, and the ratios nitrate:phosphate, nitrate:silicate, and silicate:phosphate. Statistical analyses, using general linear models, of their relationships with the absence/presence of Pseudo-nitzschia spp. found silicate (negative) to be the most influential variable common in both the west coast of Vancouver Island and Salish Sea regions. Temperature and chlorophyll a were the most influential variables which determined the log 10 abundance of Pseudo-nitzschia spp. in both regions. Analyses of the absence/presence of particulate domoic acid per Pseudo-nitzschia cell (excluding P. americana) found chlorophyll a to be the most influential variable common in both regions, whereas no common influential variable determined the log 10 concentration of particulate domoic acid per Pseudo-nitzschia cell (excluding P. americana). These results were generally similar to those of other studies from this area, although this study extends these findings to all seasons and all regions of Canada's Pacific waters. The results provide important background information against which major outbreaks and unusual events can be compared. A domoic acid surveillance program during synoptic oceanographic surveys can help to understand where and when it reaches high concentrations at sea and the potential impacts to the marine ecosystem., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Crown Copyright © 2023. Published by Elsevier B.V. All rights reserved.)

Background: Soldiers are exposed to significant repetitive head trauma, which may disrupt functional and structural brain connectivity patterns., Purpose/hypothesis: Integrate resting-state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) to characterize changes in connectivity biomarkers within Canadian Special Operations Forces (CANSOF), hypothesizing that alterations in architectural organization of cortical hubs may follow chronic repetitive head trauma., Methods: Fifteen CANSOFs with a history of chronic exposure to sub-concussive head trauma and concussive injuries (1.9 ± 2.0 concussions (range: [0-6])), as well as an equal age-matched cohort of controls (CTLs) were recruited. BOLD-based rs-fMRI was combined with DTI to reconstruct functional and structural networks using independent component analyses and probabilistic tractography. Connectivity markers were computed based on the distance between functional seeds to assess for possible differences in injury susceptibility of short- and long-range connections., Results/discussion: Significant hyper- and hypo-connectivity differences in cortical connections were observed suggesting that chronic head trauma may predispose soldiers to changes in the functional organization of brain networks. Significant structural alterations in axonal fibers directly connecting disrupted functional nodes were specific to hyper-connected long-range connections, suggesting a potential relationship between axonal injury and increases in neural recruitment following repetitive head trauma from high-exposure military duties.

National strategies to prevent sports injuries can potentially improve health outcomes at a population level and reduce medical costs. To date, a compilation of the strategies that countries have attempted, and their effectiveness, does not exist. This scoping review sets out to: identify nationwide attempts at implementing sports injury prevention strategies; examine the impact of these strategies; and map them onto the Translating Research into Injury Prevention Practice (TRIPP) framework. Using Levac's scoping review method, we: (a) identified the research questions, (b) identified relevant studies, (c) identified the study selection criteria, (d) charted the data, and (e) reported the results. A search of MEDLINE, Scopus, SPORTDiscus, CINAHL, and Web of Science databases for articles published pre-June 2019 was conducted. We identified 1794 studies and included 33 studies (of 24 strategies). The USA (n = 7), New Zealand (n = 4), Canada (n = 3), the Netherlands (n = 3), Switzerland (n = 2), Belgium (n = 1), France (n = 1), Ireland (n = 1), South Africa (n = 1), and Sweden (n = 1) have implemented nationwide sports injury prevention strategies with 29 (88%) of the included studies demonstrating positive results. Mapping the strategies onto the TRIPP framework highlighted that only four (17%) of the 24 included strategies reported on the implementation context (TRIPP Stage 5), suggesting an important reporting gap. Nationwide sports injury prevention efforts are complex, requiring a multidimensional approach. Future research should report intervention implementation data; examine the implementation context early in the research process to increase the likelihood of real-world implementation success; and could benefit from incorporating qualitative or mixed research methods., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)