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1.
Artículo en Inglés | MEDLINE | ID: mdl-38310326

RESUMEN

OBJECTIVES: ANCA associated vasculitis (AAV) is associated with significant morbidity, fatigue, pain and poor health-related quality of life (HRQoL). This review aims to assess the comprehensiveness of existing patient reported outcome measures (PROMs) used in AAV and identify associations with poorer HRQoL outcomes. METHODS: A literature review of studies using PROMs, including those labelled HRQoL in people with AAV as a primary or secondary study outcome were screened and reviewed up to July 2023. Quality was assessed using the Critical Appraisal Skills Programme. RESULTS: A total of 30 articles were included which utilised 22 different PROM tools. 76.7% (n = 23) used the SF-36 or a variation as a generic measure of health status and or HRQoL. Two studies developed a disease specific PROM. The AAV-PRO showed good psychometric properties but potential limitations in capturing all relevant aspects of the disease experience for AAV patients. Factors associated with poorer HRQoL included: neurological and sinonasal involvement, women and younger patients. 86.6% of studies showed no meaningful relationships between the SF-36 and BVAS, VDI or disease duration. Depression and anxiety were common and socioeconomic factors such as unemployment were significantly associated with poorer mental health outcomes. Glucocorticoids were found to be independently associated with worse SF-36 scores. CONCLUSION: Generic PROMs are useful in measuring significant changes but lack sensitivity to specific symptoms and unique AAV-related issues, while existing disease specific PROMs have limitations and may not fully capture AAV patient's perspective on disease and treatment burden.

2.
J Exp Psychol Gen ; 152(12): 3311-3343, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37733007

RESUMEN

People can predict their scores on the Implicit Association Test with remarkable accuracy, challenging the traditional notion that implicit attitudes are inaccessible to introspection and suggesting that people might be aware of these attitudes. Yet, major open questions about the mechanism and scope of these predictions remain, making their implications unclear. Notably, people may be inferring their attitudes from externally observable cues (e.g., in the simplest case, their demographic information) rather than accessing them directly. This problem is exacerbated by the fact that, in past work, predictions have been obtained only for a small set of targets, attitudes toward which are demonstrably possible to infer. Here, in an adversarial collaboration with eight preregistered studies (N = 8,011), we interrogate implicit attitude awareness using more stringent tests. We demonstrate that people can predict their implicit attitudes (a) across a broad range of targets (many of which are plausibly difficult to infer without introspection), (b) far more accurately than third-party observers can based on demographic information, and (c) with similar accuracy across two different widely used implicit measures. On the other hand, predictive accuracy (a) varied widely across individuals and attitude targets and (b) was partially explained by inference over nonintrospective cues such as demographic variables and explicit attitudes; moreover, (c) explicit attitudes explained considerably larger portions of variance in predictions than implicit attitudes did. Taken together, these findings suggest that successful predictions of one's implicit attitudes may emerge from multiple mechanisms, including inference over nonintrospective cues and genuine introspective access. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Actitud , Señales (Psicología) , Humanos
4.
Epigenomes ; 7(3)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37754274

RESUMEN

Long non-coding RNAs (lncRNAs), comprising a significant portion of the human transcriptome, serve as vital regulators of cellular processes and potential disease biomarkers. However, the function of most lncRNAs remains unknown, and furthermore, existing approaches have focused on gene-level investigation. Our work emphasizes the importance of transcript-level annotation to uncover the roles of specific transcript isoforms. We propose that understanding the mechanisms of lncRNA in pathological processes requires solving their structural motifs and interactomes. A complete lncRNA annotation first involves discriminating them from their coding counterparts and then predicting their functional motifs and target bio-molecules. Current in silico methods mainly perform primary-sequence-based discrimination using a reference model, limiting their comprehensiveness and generalizability. We demonstrate that integrating secondary structure and interactome information, in addition to using transcript sequence, enables a comprehensive functional annotation. Annotating lncRNA for newly sequenced species is challenging due to inconsistencies in functional annotations, specialized computational techniques, limited accessibility to source code, and the shortcomings of reference-based methods for cross-species predictions. To address these challenges, we developed a pipeline for identifying and annotating transcript sequences at the isoform level. We demonstrate the effectiveness of the pipeline by comprehensively annotating the lncRNA associated with two specific disease groups. The source code of our pipeline is available under the MIT licensefor local use by researchers to make new predictions using the pre-trained models or to re-train models on new sequence datasets. Non-technical users can access the pipeline through a web server setup.

5.
Clin Kidney J ; 16(8): 1199-1205, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37529639

RESUMEN

Focal segmental glomerulosclerosis (FSGS) is a common cause of nephrotic syndrome and whilst advances have been made in the pathophysiology, diagnostics and management of other podocytopathies, primary FSGS remains the most elusive. It has been assumed for a long time that a circulatory permeability factor exists that mediates podocyte injury, and the potential for autoantibody-mediated disease therefore raises the question as to whether patients may benefit from targeted B-cell therapy with rituximab. The prospective case series of seven patients by Roccatello et al. adds to the limited but growing evidence suggesting that B-cell depletion therapy can be safe and effective in the treatment of primary FSGS. In this editorial we explore the available evidence that suggests how and in whom rituximab may play a role in the management of primary FSGS, as well as the limitations and other potential future treatments. Further research and randomized controlled trials are needed to include larger numbers of patients, feature genetic screening and incorporate data on B-cell kinetics as a potential guide for dosing and frequency of rituximab.

6.
Best Pract Res Clin Rheumatol ; 37(1): 101828, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37244804

RESUMEN

Since its first description 40 years ago, huge strides have been made in the management of ANCA-associated vasculitis with improved patient outcomes. The use of cyclophosphamide and/or B-cell depleting therapy alongside glucocorticoids remains the cornerstone of therapy in organ or life-threatening disease, but recent trials have re-evaluated existing treatment strategies, alongside the development of new treatment targets. This has led to refinement of the role of plasma exchange, the use of reduced dosing of oral glucocorticoids with improved patient outcomes, as well as other treatment adjuvants/options of steroid minimization including C5a receptor antagonism and IL-5 inhibition. In this review we examine developments in remission induction therapy for ANCA-associated vasculitis.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Inmunosupresores , Humanos , Inmunosupresores/uso terapéutico , Rituximab/uso terapéutico , Ciclofosfamida/uso terapéutico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Inducción de Remisión
7.
Kidney360 ; 4(1): 69-77, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36700906

RESUMEN

BACKGROUND: ANCA-negative pauci-immune glomerulonephritis (PIGN) represents a rare and often under-studied subgroup of the vasculitides. This study aims to investigate differences in the clinical phenotype, renal histological features, and clinical outcomes of patients with PIGN, with and without serum ANCA positivity. METHODS: A cohort of biopsy-proven PIGN with and without detectable circulating ANCA was constructed from a single center between 2006 and 2016. Primary outcomes compared clinical presentation and histopathological features according to ANCA status, with multivariate Cox regression to compare mortality and ESKD. A systematic review and meta-analysis of the published literature was undertaken. RESULTS: In our cohort of 146 patients, 22% (n=32) had ANCA-negative disease, with a comparatively younger mean age at diagnosis; 51.4 versus 65.6 years (P<0.001). In total, 14 studies, inclusive of our cohort, were eligible for meta-analysis, totaling 301 patients who were ANCA negative. Those with ANCA-negative disease tended to have fewer extrarenal symptoms and a higher frequency of renal-limited disease, but both failed to reach statistical significance (P=0.92 and P=0.07). The risk of ESKD was significantly higher in seronegative disease (RR, 2.28; 95% confidence interval, 1.42 to 3.65; P<0.001), reflecting our experience, with a fivefold increased risk of ESKD in ANCA-negative disease (P<0.001). No significant difference in the chronicity of histopathological findings was seen and the meta-analysis showed no difference in morality (RR, 1.22; 95% confidence interval, 0.63 to 2.38; P=0.55). CONCLUSION: Our findings demonstrate that ANCA-negative PIGN presents in younger patients, with fewer extrarenal manifestations and higher ESKD risk, despite a lack of difference in histopathology. This study provides the impetus for further research into the pathogenesis, treatment response, and duration of immunotherapy in ANCA-negative disease. We suggest that the absence of positive ANCA serology should not discourage treatment and for clinical trials to include patients who are ANCA negative.


Asunto(s)
Glomerulonefritis , Vasculitis , Humanos , Anticuerpos Anticitoplasma de Neutrófilos , Estudios de Cohortes , Riñón/patología , Glomerulonefritis/epidemiología , Glomerulonefritis/terapia , Glomerulonefritis/diagnóstico , Vasculitis/patología
9.
Environ Sci Process Impacts ; 24(10): 1643-1660, 2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36196982

RESUMEN

Time series of contaminants in the Arctic are an important instrument to detect emerging issues and to monitor the effectiveness of chemicals regulation, based on the assumption of a direct reflection of changes in primary emissions. Climate change has the potential to influence these time trends, through direct physical and chemical processes and/or changes in ecosystems. This study was part of an assessment of the Arctic Monitoring and Assessment Programme (AMAP), analysing potential links between changes in climate-related physical and biological variables and time trends of persistent organic pollutants (POPs) in Arctic biota, with some additional information from the Antarctic. Several correlative relationships were identified between POP temporal trends in freshwater and marine biota and physical climate parameters such as oscillation indices, sea-ice coverage, temperature and precipitation, although the mechanisms behind these observations remain poorly understood. Biological data indicate changes in the diet and trophic level of some species, especially seabirds and polar bears, with consequences for their POP exposure. Studies from the Antarctic highlight increased POP availability after iceberg calving. Including physical and/or biological parameters in the POP time trend analysis has led to small deviations in some declining trends, but did generally not change the overall direction of the trend. In addition, regional and temporary perturbations occurred. Effects on POP time trends appear to have been more pronounced in recent years and to show time lags, suggesting that climate-related effects on the long time series might be gaining importance.


Asunto(s)
Contaminantes Ambientales , Contaminantes Orgánicos Persistentes , Monitoreo del Ambiente , Cambio Climático , Factores de Tiempo , Ecosistema , Regiones Antárticas , Regiones Árticas , Contaminantes Ambientales/análisis , Biota
10.
Sci Total Environ ; 839: 155803, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35561904

RESUMEN

Temporal trend analysis of (total) mercury (THg) concentrations in Arctic biota were assessed as part of the 2021 Arctic Monitoring and Assessment Programme (AMAP) Mercury Assessment. A mixed model including an evaluation of non-linear trends was applied to 110 time series of THg concentrations from Arctic and Subarctic biota. Temporal trends were calculated for full time series (6-46 years) and evaluated with a particular focus on recent trends over the last 20 years. Three policy-relevant questions were addressed: (1) What time series for THg concentrations in Arctic biota are currently available? (2) Are THg concentrations changing over time in biota from the Arctic? (3) Are there spatial patterns in THg trends in biota from the Arctic? Few geographical patterns of recent trends in THg concentrations were observed; however, those in marine mammals tended to be increasing at more easterly longitudes, and those of seabirds tended to be increasing in the Northeast Atlantic; these should be interpreted with caution as geographic coverage remains variable. Trends of THg in freshwater fish were equally increasing and decreasing or non-significant while those in marine fish and mussels were non-significant or increasing. The statistical power to detect trends was greatly improved compared to the 2011 AMAP Mercury Assessment; 70% of the time series could detect a 5% annual change at the 5% significance level with power ≥ 80%, while in 2011 only 19% met these criteria. Extending existing time series, and availability of new, powerful time series contributed to these improvements, highlighting the need for annual monitoring, particularly given the spatial and temporal information needed to support initiatives such as the Minamata Convention on Mercury. Collecting the same species/tissues across different locations is recommended. Extended time series from Alaska and new data from Russia are also needed to better establish circumarctic patterns of temporal trends.


Asunto(s)
Mercurio , Animales , Regiones Árticas , Biota , Monitoreo del Ambiente , Agua Dulce , Mamíferos , Mercurio/análisis
11.
Clin Kidney J ; 15(4): 618-623, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35371453

RESUMEN

The association between cardiovascular (CV) disease and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is well documented. The recent work by Massicotte-Azarniouch et al. confirms the risk and adds to the existing evidence by describing the highest risk in the first 3 months after diagnosis. In this review, we aim to put their findings into perspective and formulate implications for the care of AAV patients. We discuss mechanisms for increased CV disease in AAV, including the impact of traditional risk factors and disease-related risks such as renal impairment and anti-myeloperoxidase (MPO) ANCA serotype. We also provide a brief primer on the impact of inflammatory-driven endothelial dysfunction and platelet activation on accelerated atherosclerosis in AAV patients. These features alongside the impact of disease activity and systemic inflammation provide potential explanations to why the incidence of CV events is highest in the first 3 months from diagnosis. We suggest future avenues of research, provide some suggestions to address and treat CV risk based on current evidence, and highlight the importance of addressing this topic early on. Addressing modifiable risk factors, dialogue with patients, patient information and a structured approach overall will be key to improve CV outcomes in AAV.

12.
Cognition ; 225: 105104, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35366483

RESUMEN

Every day, people face choices which could produce negative outcomes for others, and understanding these decisions is a major aim of social psychology. Here, we show that episodic simulation - a key psychological process implicated in other types of social and moral decision-making - can play a surprising role. Across six experiments, we find that imagining performing actions which adversely affect others makes people report a higher likelihood of performing those actions in the future. This effect happens, in part, because when people construe the actions as morally justified (as they often do spontaneously), imagining doing it makes them feel good. These findings stand in contrast to traditional accounts of harm aversion in moral psychology, and instead contribute to a growing body of evidence that people often cast harming others in a positive light.


Asunto(s)
Memoria Episódica , Principios Morales , Afecto , Toma de Decisiones , Emociones , Predicción , Humanos
13.
Sci Total Environ ; 834: 155221, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35427623

RESUMEN

Global climate change has led to profound alterations of the Arctic environment and ecosystems, with potential secondary effects on mercury (Hg) within Arctic biota. This review presents the current scientific evidence for impacts of direct physical climate change and indirect ecosystem change on Hg exposure and accumulation in Arctic terrestrial, freshwater, and marine organisms. As the marine environment is elevated in Hg compared to the terrestrial environment, terrestrial herbivores that now exploit coastal/marine foods when terrestrial plants are iced over may be exposed to higher Hg concentrations. Conversely, certain populations of predators, including Arctic foxes and polar bears, have shown lower Hg concentrations related to reduced sea ice-based foraging and increased land-based foraging. How climate change influences Hg in Arctic freshwater fishes is not clear, but for lacustrine populations it may depend on lake-specific conditions, including interrelated alterations in lake ice duration, turbidity, food web length and energy sources (benthic to pelagic), and growth dilution. In several marine mammal and seabird species, tissue Hg concentrations have shown correlations with climate and weather variables, including climate oscillation indices and sea ice trends; these findings suggest that wind, precipitation, and cryosphere changes that alter Hg transport and deposition are impacting Hg concentrations in Arctic marine organisms. Ecological changes, including northward range shifts of sub-Arctic species and altered body condition, have also been shown to affect Hg levels in some populations of Arctic marine species. Given the limited number of populations and species studied to date, especially within Arctic terrestrial and freshwater systems, further research is needed on climate-driven processes influencing Hg concentrations in Arctic ecosystems and their net effects. Long-term pan-Arctic monitoring programs should consider ancillary datasets on climate, weather, organism ecology and physiology to improve interpretation of spatial variation and time trends of Hg in Arctic biota.


Asunto(s)
Mercurio , Animales , Regiones Árticas , Cambio Climático , Ecosistema , Monitoreo del Ambiente , Lagos , Mamíferos , Mercurio/análisis
14.
J Neurosci ; 42(20): 4116-4130, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35410881

RESUMEN

Neurons in posterior parietal cortex (PPC) encode many aspects of the sensory world (e.g., scene structure), the posture of the body, and plans for action. For a downstream computation, however, only some of these dimensions are relevant; the rest are "nuisance variables" because their influence on neural activity changes with sensory and behavioral context, potentially corrupting the read-out of relevant information. Here we show that a key postural variable for vision (eye position) is represented robustly in male macaque PPC across a range of contexts, although the tuning of single neurons depended strongly on context. Contexts were defined by different stages of a visually guided reaching task, including (1) a visually sparse epoch, (2) a visually rich epoch, (3) a "go" epoch in which the reach was cued, and (4) during the reach itself. Eye position was constant within trials but varied across trials in a 3 × 3 grid spanning 24° × 24°. Using demixed principal component analysis of neural spike-counts, we found that the subspace of the population response encoding eye position is orthogonal to that encoding task context. Accordingly, a context-naive (fixed-parameter) decoder was nevertheless able to estimate eye position reliably across contexts. Errors were small given the sample size (∼1.78°) and would likely be even smaller with larger populations. Moreover, they were comparable to that of decoders that were optimized for each context. Our results suggest that population codes in PPC shield encoded signals from crosstalk to support robust sensorimotor transformations across contexts.SIGNIFICANCE STATEMENT Neurons in posterior parietal cortex (PPC) which are sensitive to gaze direction are thought to play a key role in spatial perception and behavior (e.g., reaching, navigation), and provide a potential substrate for brain-controlled prosthetics. Many, however, change their tuning under different sensory and behavioral contexts, raising the prospect that they provide unreliable representations of egocentric space. Here, we analyze the structure of encoding dimensions for gaze direction and context in PPC during different stages of a visually guided reaching task. We use demixed dimensionality reduction and decoding techniques to show that the coding of gaze direction in PPC is mostly invariant to context. This suggests that PPC can provide reliable spatial information across sensory and behavioral contexts.


Asunto(s)
Lóbulo Parietal , Desempeño Psicomotor , Animales , Macaca , Masculino , Neuronas/fisiología , Lóbulo Parietal/fisiología , Desempeño Psicomotor/fisiología , Percepción Espacial/fisiología
15.
Cognition ; 225: 105116, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35397347

RESUMEN

Causal relationships, unlike mere co-occurrence, allow humans to obtain rewards and avoid punishments by intervening on their environment. Accordingly, explicit (controlled) evaluations of stimuli encountered in the environment are known to be sensitive to causal relationships above and beyond mere co-occurrence. In this project, we conduct stringent tests of whether implicit (automatic) evaluation also reflects causal relationships and begin to probe the representational mechanisms underlying such sensitivity. Participants (N = 4836) observed causal events during which two stimuli were equally contingent with positive or negative outcomes but only one of them was causally responsible for these outcomes. Across 6 studies, varying in design and amount of verbal scaffolding provided, differences in causal status consistently guided not only explicit measures of evaluation (Likert and slider scales; Bayes Factor meta-analysis: Cohen's d = 0.28, BF10 > 1046) but also their implicit counterparts (Implicit Association Tests; Bayes Factor meta-analysis: Cohen's d = 0.22, BF10 > 1029). However, unlike their explicit counterparts, implicit evaluations were not sensitive to causal relationships that had to be flexibly derived by combining disparate past experiences. Taken together, these studies suggest that implicit evaluations are sensitive to causal information. Such sensitivity seems to be mediated via precompiled, causally informed value representations rather than online computations over a causal model.


Asunto(s)
Teorema de Bayes , Causalidad , Humanos
16.
Molecules ; 27(7)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35408711

RESUMEN

Biospectroscopy offers the ability to simultaneously identify key biochemical changes in tissue associated with a given pathological state to facilitate biomarker extraction and automated detection of key lesions. Herein, we evaluated the application of machine learning in conjunction with Raman spectroscopy as an innovative low-cost technique for the automated computational detection of disease activity in anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis (AAGN). Consecutive patients with active AAGN and those in disease remission were recruited from a single UK centre. In those with active disease, renal biopsy samples were collected together with a paired urine sample. Urine samples were collected immediately prior to biopsy. Amongst those in remission at the time of recruitment, archived renal tissue samples representative of biopsies taken during an active disease period were obtained. In total, twenty-eight tissue samples were included in the analysis. Following supervised classification according to recorded histological data, spectral data from unstained tissue samples were able to discriminate disease activity with a high degree of accuracy on blind predictive modelling: F-score 95% for >25% interstitial fibrosis and tubular atrophy (sensitivity 100%, specificity 90%, area under ROC 0.98), 100% for necrotising glomerular lesions (sensitivity 100%, specificity 100%, area under ROC 1) and 100% for interstitial infiltrate (sensitivity 100%, specificity 100%, area under ROC 0.97). Corresponding spectrochemical changes in paired urine samples were limited. Future larger study is required, inclusive of assigned variables according to novel non-invasive biomarkers as well as the application of forward feature extraction algorithms to predict clinical outcomes based on spectral features.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Glomerulonefritis , Enfermedades Renales , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/patología , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/orina , Anticuerpos Anticitoplasma de Neutrófilos , Biomarcadores/orina , Biopsia , Glomerulonefritis/diagnóstico , Glomerulonefritis/patología , Humanos , Riñón/patología , Enfermedades Renales/patología , Proyectos Piloto , Espectrometría Raman
17.
Sci Total Environ ; 829: 154445, 2022 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-35304145

RESUMEN

There has been a considerable number of reports on Hg concentrations in Arctic mammals since the last Arctic Monitoring and Assessment Programme (AMAP) effort to review biological effects of the exposure to mercury (Hg) in Arctic biota in 2010 and 2018. Here, we provide an update on the state of the knowledge of health risk associated with Hg concentrations in Arctic marine and terrestrial mammal species. Using available population-specific data post-2000, our ultimate goal is to provide an updated evidence-based estimate of the risk for adverse health effects from Hg exposure in Arctic mammal species at the individual and population level. Tissue residues of Hg in 13 species across the Arctic were classified into five risk categories (from No risk to Severe risk) based on critical tissue concentrations derived from experimental studies on harp seals and mink. Exposure to Hg lead to low or no risk for health effects in most populations of marine and terrestrial mammals, however, subpopulations of polar bears, pilot whales, narwhals, beluga and hooded seals are highly exposed in geographic hotspots raising concern for Hg-induced toxicological effects. About 6% of a total of 3500 individuals, across different marine mammal species, age groups and regions, are at high or severe risk of health effects from Hg exposure. The corresponding figure for the 12 terrestrial species, regions and age groups was as low as 0.3% of a total of 731 individuals analyzed for their Hg loads. Temporal analyses indicated that the proportion of polar bears at low or moderate risk has increased in East/West Greenland and Western Hudson Bay, respectively. However, there remain numerous knowledge gaps to improve risk assessments of Hg exposure in Arctic mammalian species, including the establishment of improved concentration thresholds and upscaling to the assessment of population-level effects.


Asunto(s)
Caniformia , Mercurio , Phocidae , Ursidae , Animales , Regiones Árticas , Monitoreo del Ambiente , Mamíferos , Mercurio/toxicidad , Medición de Riesgo
18.
Psychol Inq ; 33(4): 280-284, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37974599
19.
Environ Res ; 207: 112169, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-34624268

RESUMEN

Temporal trends of mercury in Arctic wildlife are inconsistent within and between species and are often insignificant, which limits data interpretation. Recent multivariate analyses have shown that weather and climate factors (e.g. temperatures, sea ice conditions) are related to total Hg (THg) concentrations in wildlife tissues, though relatively few studies have explored these relationships. The present study compared time series of THg concentrations in liver of polar bear (Ursus maritimus, 2007/08-2015/16), eggs of thick-billed murres (Uria lomvia, 1993-2015) and kidney of caribou (Rangifer tarandus groenlandicus, 2006-2015) from the Hudson Bay region of Canada and statistically modelled THg over time with available climate and weather data. Significant temporal trends of THg concentrations were not detected in any species. However, in multivariate models that included time-lagged sea ice freeze up dates, THg concentrations increased 4.4% yr-1 in Qamanirjuaq caribou. Sea ice conditions were also related to THg levels in polar bear liver but not those in eggs of murres, though year was not a signifcant factor. Greater precipitation levels one to two years prior to sampling were associated with greater THg concentrations in polar bears and caribou, likely due to greater deposition, flooding and discharge from nearby wetlands and rivers. Time-lagged Arctic and/or North Atlantic Oscillation (AO/NAO) indices also generated significant, inverse models for all three species, agreeing with relationships in other time series of similar length. The magnitude and direction of many relationships were affected by season, duration of time-lags, and the length of the time series. Our findings support recent observations suggesting that temporal studies monitoring Hg in Arctic wildlife should consider including key climatic or weather factors to help identify consistent variables of influence and to improve temporal analyses of THg time series.


Asunto(s)
Charadriiformes , Mercurio , Reno , Ursidae , Animales , Regiones Árticas , Cambio Climático , Monitoreo del Ambiente , Mercurio/análisis , Temperatura
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