Demonstrating the reliability of in vivo metabolomics based chemical grouping: towards best practice.

While grouping/read-across is widely used to fill data gaps, chemical registration dossiers are often rejected due to weak category justifications based on structural similarity only. Metabolomics provides a route to robust chemical categories via evidence of shared molecular effects across source and target substances. To gain international acceptance, this approach must demonstrate high reliability, and best-practice guidance is required. The MetAbolomics ring Trial for CHemical groupING (MATCHING), comprising six industrial, government and academic ring-trial partners, evaluated inter-laboratory reproducibility and worked towards best-practice. An independent team selected eight substances (WY-14643, 4-chloro-3-nitroaniline, 17α-methyl-testosterone, trenbolone, aniline, dichlorprop-p, 2-chloroaniline, fenofibrate); ring-trial partners were blinded to their identities and modes-of-action. Plasma samples were derived from 28-day rat tests (two doses per substance), aliquoted, and distributed to partners. Each partner applied their preferred liquid chromatography-mass spectrometry (LC-MS) metabolomics workflows to acquire, process, quality assess, statistically analyze and report their grouping results to the European Chemicals Agency, to ensure the blinding conditions of the ring trial. Five of six partners, whose metabolomics datasets passed quality control, correctly identified the grouping of eight test substances into three categories, for both male and female rats. Strikingly, this was achieved even though a range of metabolomics approaches were used. Through assessing intrastudy quality-control samples, the sixth partner observed high technical variation and was unable to group the substances. By comparing workflows, we conclude that some heterogeneity in metabolomics methods is not detrimental to consistent grouping, and that assessing data quality prior to grouping is essential. We recommend development of international guidance for quality-control acceptance criteria. This study demonstrates the reliability of metabolomics for chemical grouping and works towards best-practice.

Evidence of altered fatty acid metabolism in dogs with naturally occurring valvular heart disease and congestive heart failure.

INTRODUCTION: Myxomatous mitral valve disease (MMVD) is the most common cardiac condition in adult dogs. The disease progresses over several years and affected dogs may develop congestive heart failure (HF). Research has shown that myocardial metabolism is altered in cardiac disease, leading to a reduction in ß-oxidation of fatty acids and an increased dependence upon glycolysis. OBJECTIVES: This study aimed to evaluate whether a shift in substrate use occurs in canine patients with MMVD; a naturally occurring model of human disease. METHODS: Client-owned dogs were longitudinally evaluated at a research clinic in London, UK and paired serum samples were selected from visits when patients were in ACVIM stage B1: asymptomatic disease without cardiomegaly, and stage C: HF. Samples were processed using ultra-performance liquid chromatography mass spectrometry and lipid profiles were compared using mixed effects models with false discovery rate adjustment. The effect of disease stage was evaluated with patient breed entered as a confounder. Features that significantly differed were screened for selection for annotation efforts using reference databases. RESULTS: Dogs in HF had altered concentrations of lipid species belonging to several classes previously associated with cardiovascular disease. Concentrations of certain acylcarnitines, phospholipids and sphingomyelins were increased after individuals had developed HF, whilst some ceramides and lysophosphatidylcholines decreased. CONCLUSIONS: The canine metabolome appears to change as MMVD progresses. Findings from this study suggest that in HF myocardial metabolism may be characterised by reduced ß-oxidation. This proposed explanation warrants further research.

An ancient, Antarctic-specific species complex: large divergences between multiple Antarctic lineages of the tardigrade genus Mesobiotus.

Antarctica has been isolated and progressively glaciated for over 30 million years, with only approximately 0.3 % of its area currently ice-free and capable of supporting terrestrial ecosystems. As a result, invertebrate populations have become isolated and fragmented, in some cases leading to speciation. Terrestrial invertebrate species currently found in Antarctica often show multi-million year, and even Gondwanan, heritage, with little evidence of recent colonisation. Mesobiotus is a globally distributed tardigrade genus. It has commonly been divided into two "groups", referred to as harmsworthi and furciger, with both groups currently considered cosmopolitan, with global reports including from both the Arctic and the Antarctic. However, some authors considered that Meb. furciger, as originally described, may represent an Antarctic-specific lineage. Using collections of tardigrades from across the Antarctic continent and publicly available sequences obtained from online databases, we use mitochondrial and nuclear ribosomal sequence data to clarify the relationships of Antarctic Mesobiotus species. Our analyses show that all Antarctic members belong to a single lineage, evolving separately from non-Antarctic representatives. Within this Antarctic lineage there are further deep divisions among geographic regions of the continent, consistent with the presence of a species complex. Based on our data confirming the deep divisions between this Antarctic lineage, which includes representatives of both groups, we recommend that the use of furciger and harmsworthi group terminology is now abandoned, as it leads to systematic and biogeographical confusion.

Societal importance of Antarctic negative feedbacks on climate change: blue carbon gains from sea ice, ice shelf and glacier losses.

Diminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth's biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses-becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60-100 MtCyear-1), ice shelves (4-40 MtCyear-1 = giant iceberg generation) and glacier retreat (< 1 MtCyear-1). Estimates suggest that, amongst these, reduced duration of seasonal sea ice is most important. Decreasing sea ice extent drives longer (not necessarily larger biomass) smaller cell-sized phytoplankton blooms, increasing growth of many primary consumers and benthic carbon storage-where sequestration chances are maximal. However, sea ice losses also create positive feedbacks in shallow waters through increased iceberg movement and scouring of benthos. Unlike loss of sea ice, which enhances existing sinks, ice shelf losses generate brand new carbon sinks both where giant icebergs were, and in their wake. These also generate small positive feedbacks from scouring, minimised by repeat scouring at biodiversity hotspots. Blue carbon change from glacier retreat has been least well quantified, and although emerging fjords are small areas, they have high storage-sequestration conversion efficiencies, whilst blue carbon in polar waters faces many diverse and complex stressors. The identity of these are known (e.g. fishing, warming, ocean acidification, non-indigenous species and plastic pollution) but not their magnitude of impact. In order to mediate multiple stressors, research should focus on wider verification of blue carbon gains, projecting future change, and the broader environmental and economic benefits to safeguard blue carbon ecosystems through law.

Marine plastics threaten giant Atlantic Marine Protected Areas.

There has been a recent shift in global perception of plastics in the environment, resulting in a call for greater action. Science and the popular media have highlighted plastic as an increasing stressor [1,2]. Efforts have been made to confer protected status to some remote locations, forming some of the world's largest Marine Protected Areas, including several UK overseas territories. We assessed plastic at these remote Atlantic Marine Protected Areas, surveying the shore, sea surface, water column and seabed, and found drastic changes from 2013-2018. Working from the RRS James Clark Ross at Ascension, St. Helena, Tristan da Cunha, Gough and the Falkland Islands (Figure 1A), we showed that marine debris on beaches has increased more than 10 fold in the past decade. Sea surface plastics have also increased, with in-water plastics occurring at densities of 0.1 items m-3; plastics on seabeds were observed at ≤ 0.01 items m-2. For the first time, beach densities of plastics at remote South Atlantic sites approached those at industrialised North Atlantic sites. This increase even occurs hundreds of meters down on seamounts. We also investigated plastic incidence in 2,243 animals (comprising 26 species) across remote South Atlantic oceanic food webs, ranging from plankton to seabirds. We found that plastics had been ingested by primary consumers (zooplankton) to top predators (seabirds) at high rates. These findings suggest that MPA status will not mitigate the threat of plastic proliferation to this rich, unique and threatened biodiversity.

Cutaneous Metastases from Urothelial Carcinoma of the Bladder: A Rare Presentation and Literature Review.

With the advances in imaging, earlier detection of recurrence and metastatic disease is possible. However, there are limited data on the metastatic pattern of bladder cancer. In addition, cutaneous metastases from primary genitourinary malignancies are rare and, in spite of advances in imaging, which detect smaller lesions, the patterns of metastases from bladder cancer have not been well described. Very few cases of skin metastasis from urothelial carcinoma have been reported in the past. We present a case of primary bladder transitional cell carcinoma in which a cutaneous metastasis was the initial presentation.

Catchments catch all: long-term population history of a giant springtail from the southeast Australian highlands--a multigene approach.

Phylogeography can reveal evolutionary processes driving natural genetic-geographical patterns in biota, providing an empirical framework for optimizing conservation strategies. The long-term population history of a rotting-log-adapted giant springtail (Collembola) from montane southeast Australia was inferred via joint analysis of mitochondrial and multiple nuclear gene genealogies. Contemporary populations were identified using multilocus nuclear genotype clustering. Very fine-scale sampling combined with nested clade and coalescent-based analyses of sequences from mitochondrial cytochrome oxidase I and three unlinked nuclear loci uncovered marked population structure, deep molecular divergences, and abrupt phylogeographical breaks over distances on the order of tens of kilometres or less. Despite adaptations that confer low mobility, rare long-distance gene flow was implicated: novel computer simulations that jointly modelled stochasticity inherent in coalescent processes and that of DNA sequence evolution showed that incomplete lineage sorting alone was unable to explain the observed spatial-genetic patterns. Impacts of Pleistocene or earlier climatic cycles were detected on multiple timescales, and at least three putative moist forest refuges were identified. Water catchment divisions predict phylogeographical patterning and present-day population structure with high precision, and may serve as an excellent surrogate for biodiversity indication in sedentary arthropods from topographically heterogeneous montane temperate forests.

Quality assurance of neuroradiology in a District General Hospital.

BACKGROUND: An increasing number of neurologists in District General Hospitals (DGHs) rely on local neuroimaging reports from general radiologists. AIM: To determine the level of disagreement between general radiologists and neuroradiologists in reporting neuroimaging from patients referred to a neurologist. DESIGN: Prospective observational study. METHODS: We studied 232 patients referred for a neuroradiologist's report on neuroimaging over a 17-month period. Pre-planned comparisons included primary and secondary report findings, length of report and suggestions for additional investigations. RESULTS: Of the 593 patients assessed during the study period, a neuroradiologist's report was sought for 232 (39%): 119 men, 113 women, mean age 46.1 (SD 17.6) years. Primary findings differed in 37 patients (15.9%) (95%CI 11.5-21.3). Reports from neuroradiologists changed subsequent management in 31 (13.4%) (95%CI 9.3-18.4). Differences in secondary findings occurred in 52 (22.4%) (95%CI 17.2-28.3), and differences in either primary or secondary outcomes in 77 (33.2%) (95%CI 27.2-39.6). The level of disagreement in primary findings was as frequent among patients investigated with magnetic resonance imaging as among computerized tomogram-only patients (p = 0.13). Neuroradiologists recommended additional investigations for 24 patients (10.3%) (95%CI 6.7-15.0) and provided longer reports than general radiologists (p < 0.001). DISCUSSION: Neuroimaging reports of some patients differ substantially between general radiologists and neuroradiologists. Optimal management of neurological patients in DGHs may require timely access to neuroradiologists.

Phylogeography recapitulates topography: very fine-scale local endemism of a saproxylic 'giant' springtail at Tallaganda in the Great Dividing Range of south-east Australia.

Comparative phylogeography can reveal processes and historical events that shape the biodiversity of species and communities. As part of a comparative research program, the phylogeography of a new, endemic Australian genus and species of log-dependent (saproxylic) collembola was investigated using mitochondrial sequences, allozymes and anonymous single-copy nuclear markers. We found the genetic structure of the species corresponds with five a priori microbiogeographical regions, with population subdivision at various depths owing to palaeoclimatic influences. Closely related mtDNA haplotypes are codistributed within a single region or occur in adjacent regions, nuclear allele frequencies are more similar among more proximate populations, and interpopulation migration is rare. Based on mtDNA divergence, a late Miocene-late Pliocene coalescence is likely. The present-day distribution of genetic diversity seems to have been impacted by three major climatic events: Pliocene cooling and drying (2.5-7 million years before present, Mybp), early Pleistocene wet-dry oscillations (c. 1.2 Mybp) and the more recent glacial-interglacial cycles that have characterized the latter part of the Quaternary (<0.4 Mybp).

Population pharmacokinetics of digoxin in Korean patients.

AIM: Digoxin possesses a narrow therapeutic index and shows a large inter-patient pharmacokinetic variability. The purpose of this study was to develop a population model for the pharmacokinetics of digoxin in Korean patients. METHODS: Plasma concentrations of digoxin after multiple administration at varying dosing schedules in Korean patients were used for population modeling. Data analysis was performed with the P-Pharm software. The data were best fitted by a one-compartment model. The effect of demographic and clinical factors like sex, age, weight, disease state, and renal function on the pharmacokinetic parameters of digoxin was investigated. RESULTS: The study indicated that the clearance of digoxin was influenced by creatinine clearance, while body weight and creatinine clearance were the covariates for its volume of distribution. The population mean estimates for CL and V were 4.4 l/h and 535 l, respectively. Absorption rate constant was lower in females and in the presence of concomitant drug treatment. CONCLUSION: A population pharmacokinetic model for the digoxin pharmacokinetics in a section of Korean patients was developed. The relationships between the pharmacokinetic parameters and the demographic data and the patient-specific covariates were established.

A randomized trial of breast cancer risk counseling: the impact on self-reported mammography use.

OBJECTIVES: We evaluated the impact of individualized breast cancer risk counseling on mammography use among women at risk for breast cancer. METHODS: Participants (n = 508) were randomized to the breast cancer risk counseling intervention or a general health education control intervention, and 85% completed follow-up. RESULTS: In multivariate modeling, a significant group-by-education interaction demonstrated that among less-educated participants, breast cancer risk counseling led to reduced mammography use. There was no intervention effect among the more-educated participants. CONCLUSIONS: These results suggest that standard breast cancer risk counseling could have an adverse impact on the health behaviors of less-educated women.

Epidermal Langerhans cell apoptosis is induced in vivo by nonanoic acid but not by sodium lauryl sulphate.

Exposure to irritants may cause chronic irritant contact dermatitis (ICD), characterized by irregular epidermal thickening and a predominantly dermal mononuclear cell infiltrate. The mechanisms involved, and why only certain individuals are affected, are not clearly understood. Different irritants may trigger different cellular and molecular interactions between resident skin cells and recruited inflammatory cells. In some individuals these interactions may become self-perpetuating resulting in persistent inflammation in the absence of continued exposure. This study examined Langerhans cell (LC) density in clinically normal skin of 46 patients with chronic ICD and 10 healthy individuals, and compared the action of the two irritants nonanoic acid (NA) and sodium lauryl sulphate (SLS) on the LCs and keratinocytes of clinically normal skin in patients with chronic ICD. There was a higher number of LCs/mm basement membrane in patients compared with controls, although there was no difference in the number of dendrites/LC nor in dendrite length. SLS induced keratinocyte proliferation after 48 h exposure, had no effect on LC number or distribution, and induced keratinocyte apoptosis after 24 and 48 h exposure. In contrast, NA decreased keratinocyte proliferation after 24 h exposure but this returned to basal levels after 48 h, and induced epidermal cell apoptosis after only 6 h exposure. NA dramatically decreased LC number after 24 and 48 h exposure, which was accompanied by basal redistribution and decreased dendrite length. Most significantly, NA induced apoptosis in over half of the LCs present after 24 and 48 h exposure.

Improving the management of children's pain in A&E.

This paper describes a project that sought to improve the management of children's pain in an A&E department. Pain management is not always seen as a priority in A&E departments. The problems are highlighted through two case studies, and guidelines to improve practice were developed in collaboration with a specialist multidisciplinary team.

Epidermal keratinocyte production of interferon-gamma immunoreactive protein and mRNA is an early event in allergic contact dermatitis.

Previous work has indicated the importance of cytokine cascades in the induction of contact dermatitis, but there is little information on the cellular localization of cytokines in human skin, particularly during the early phases of the inflammatory response to contact allergens. Using in situ hybridization for mRNA and immunocytochemistry on biopsies from a series of 16 patients with known allergic contact dermatitis, we examined the kinetics of early cytokine production after challenge with relevant or irrelevant antigen. We show that epidermal keratinocytes from patients challenged in vivo with allergen, but not irrelevant antigen, rapidly synthesize (within 4 h) mRNA for interferon-gamma and produce immunoreactive interferon-gamma. Interleukin-1alpha and interleukin-8 mRNA were also detected but showed no correlation with relevant antigen challenge. This study demonstrates that keratinocytes can produce interferon-gamma and that this production is linked to challenge with relevant antigen in allergic contact dermatitis. These findings indicate that keratinocytes may amplify allergen-specific T-lymphocyte-triggered interferon-gamma dependent responses and might partially explain the speed of reaction in this common disease and other delayed hypersensitivity reactions involving the skin.

A randomized trial of breast cancer risk counseling: interacting effects of counseling, educational level, and coping style.

The authors evaluated the impact of individualized breast cancer risk counseling (BCRC) on breast-cancer-specific distress and general distress in 239 women with a family history of breast cancer. Following a baseline assessment of demographics, risk factors, coping styles, and distress, participants were assigned randomly to receive either BCRC or general health education (GHE; i.e., control group). After controlling for education level, women who received BCRC had significantly less breast-cancer-specific distress at 3-month follow-up compared with women who received GHE. A significant Education Level x Treatment Group interaction indicated that the psychological benefits of BCRC were greater for women with less formal education. In both the BCRC and GHE groups, participants who had monitoring coping styles exhibited increases in general distress from baseline to follow-up.

Effect of ranitidine on theophylline metabolism in healthy Koreans living in China.

OBJECTIVE: To evaluate the effect of concurrent ranitidine therapy on theophylline metabolism in healthy Koreans. DESIGN: A 4-week, double-blind, randomized, placebo-controlled, crossover study. SETTING: The Clinical Research Unit, Department of Pharmaceutical Sciences, Yanbian Medical College, Yanji, China. SUBJECTS: Six young, healthy, nonsmoking Korean volunteers residing in China with no known factors that would alter theophylline metabolism. INTERVENTIONS: Subjects received extended-release oral theophylline at a constant dosage over 4 weeks to yield a serum concentration (Cp) between 5 and 10 micrograms/mL. Week 1 was the dosage titration phase. During week 2 subjects randomly received either ranitidine or a matching placebo. Week 3 was a washout phase, and during week 4 subjects were crossed over to receive either placebo or ranitidine. At the end of each treatment week, serum and urinary metabolite concentrations were measured. OUTCOME MEASURES: Theophylline serum concentrations and urinary concentrations of 1-methylxanthine, 1-methyluric acid, 3-methylxanthine, and 1,3-dimethyluric acid were measured. Estimates of clearance (Cl), volume of distribution (Vd), and half-life (t1/2) were determined. RESULTS: Concurrent administration of ranitidine with theophylline did not significantly alter theophylline Cp, Cl, Vd, or t1/2. Urinary concentrations of major theophylline metabolites also were not changed. CONCLUSIONS: Ranitidine does not significantly alter the metabolism of theophylline in healthy Koreans residing in China.

Gail model breast cancer risk components are poor predictors of risk perception and screening behavior.

The Gail model is being used increasingly to determine individual breast cancer risk and to tailor preventive health recommendations accordingly. Although widely known to the medical and biostatistical communities, the risk factors included in the model may not be salient to the women to whom the model is being applied. This study explored the relationship of the individual Gail model risk factors to perceived risk of breast cancer and prior breast cancer screening among women with a family history of breast cancer. Data from baseline interviews with 969 women found a striking disparity between the objective risk factors included in the model and the accuracy of perceived risk and screening behaviors of this population, particularly among women over the age of 50 years. Risk perception accuracy was unrelated to all of the Gail model risk factors for all age groups. Reported mammography adherence was only associated with having had a breast biopsy in both age groups. Breast self examination (BSE) practice was independent of all measured factors for both age groups. These findings support the need for further research to identify additional determinants of risk perception and motivators of screening behavior.

Effects of individualized breast cancer risk counseling: a randomized trial.

BACKGROUND: Studies have shown that a majority of women with a family history of breast cancer have exaggerated perceptions of their own risk of this disease and experience excessive anxiety. In response to the need to communicate more accurate risk information to these women, specialized programs for breast cancer risk counseling have been initiated in medical centers across the United States. PURPOSE: Our purpose was 1) to evaluate the impact of a standardized protocol for individualized breast cancer risk counseling on comprehension of personal risk among first-degree relatives of index breast cancer patients and 2) to identify women most and least likely to benefit from such counseling. METHODS: This study is a prospective randomized trial comparing individualized breast cancer risk counseling to general health counseling (control). We studied 200 women aged 35 years and older who had a family history of breast cancer in a first-degree relative. Women with a personal history of cancer were excluded. Risk comprehension was assessed as the concordance between perceived "subjective" lifetime breast cancer risk and estimated "objective" lifetime risk. RESULTS: The results of logistic regression analysis showed that women who received risk counseling were significantly more likely to improve their risk comprehension, compared with women in the control condition (odds ratio [OR] = 3.5; 95% confidence interval [CI] = 1.3-9.5; P = .01). However, in both groups, about two thirds of women continued to overestimate their lifetime risks substantially following counseling. Examination of subjects by treatment interaction effects indicated that risk counseling did not produce improved comprehension among the large proportion of women who had high levels of anxious preoccupation with breast cancer at base line (P = .02). In addition, white women were less likely to benefit than African-American women (OR = 0.34; 95% CI = 0.11-0.99; P = .05). CONCLUSION: Efforts to counsel women about their breast cancer risks are not likely to be effective unless their breast cancer anxieties are also addressed. IMPLICATIONS: Attention to the psychological aspects of breast cancer risk will be critical in the development of risk-counseling programs that incorporate testing for the recently cloned breast cancer susceptibility gene, BRCA1 (and BRCA2 when that gene has also been cloned).