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1.
Glob Chang Biol ; 30(1): e17013, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37994377

RESUMO

Lakes worldwide are affected by multiple stressors, including climate change. This includes massive loading of both nutrients and humic substances to lakes during extreme weather events, which also may disrupt thermal stratification. Since multi-stressor effects vary widely in space and time, their combined ecological impacts remain difficult to predict. Therefore, we combined two consecutive large enclosure experiments with a comprehensive time-series and a broad-scale field survey to unravel the combined effects of storm-induced lake browning, nutrient enrichment and deep mixing on phytoplankton communities, focusing particularly on potentially toxic cyanobacterial blooms. The experimental results revealed that browning counteracted the stimulating effect of nutrients on phytoplankton and caused a shift from phototrophic cyanobacteria and chlorophytes to mixotrophic cryptophytes. Light limitation by browning was identified as the likely mechanism underlying this response. Deep-mixing increased microcystin concentrations in clear nutrient-enriched enclosures, caused by upwelling of a metalimnetic Planktothrix rubescens population. Monitoring data from a 25-year time-series of a eutrophic lake and from 588 northern European lakes corroborate the experimental results: Browning suppresses cyanobacteria in terms of both biovolume and proportion of the total phytoplankton biovolume. Both the experimental and observational results indicated a lower total phosphorus threshold for cyanobacterial bloom development in clearwater lakes (10-20 µg P L-1 ) than in humic lakes (20-30 µg P L-1 ). This finding provides management guidance for lakes receiving more nutrients and humic substances due to more frequent extreme weather events.


Assuntos
Cianobactérias , Fitoplâncton , Lagos/microbiologia , Substâncias Húmicas , Eutrofização , Nutrientes , Fósforo/análise , China
2.
Osteoporos Int ; 33(4): 791-806, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34590158

RESUMO

High-resolution peripheral quantitative computed tomography (HR-pQCT) is a powerful tool to assess bone health. To determine how an individual's or population of interest's HR-pQCT outcomes compare to expected, reference data are required. This study provides reference data for HR-pQCT measures acquired in a population of White adults. PURPOSE: To provide age- and sex-specific reference data for high-resolution peripheral quantitative computed tomography (HR-pQCT) measures of the distal and diaphyseal radius and tibia acquired using a second-generation scanner and percent-of-length offsets proximal from the end of the bone. METHODS: Data were acquired in White adults (aged 18-80 years) living in the Midwest region of the USA. HR-pQCT scans were performed at the 4% distal radius, 30% diaphyseal radius, 7.3% distal tibia, and 30% diaphyseal tibia. Centile curves were fit to the data using the LMS approach. RESULTS: Scans of 867 females and 317 males were included. The fitted centile curves reveal HR-pQCT differences between ages, sexes, and sites. They also indicate differences when compared to data obtained by others using fixed length offsets. Excel-based calculators based on the current data were developed and are provided to enable computation of subject-specific percentiles, z-scores, and t-scores and to plot an individual's outcomes on the fitted curves. In addition, regression equations are provided to convert estimated failure load acquired with the conventional criteria utilized with first-generation scanners and those specifically developed for second-generation scanners. CONCLUSION: The current study provides unique data and resources. The combination of the reference data and calculators provide clinicians and investigators an ability to assess HR-pQCT outcomes in an individual or population of interest, when using the described scanning and analysis procedure. Ultimately, the expectation is these data will be expanded over time so the wealth of information HR-pQCT provides becomes increasingly interpretable and utilized.


Assuntos
Rádio (Anatomia) , Tíbia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Osso e Ossos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
3.
Int Endod J ; 55(5): 531-543, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35263803

RESUMO

AIM: To evaluate the effect of various rotational motions on the torque/force generation, surface wear, and shaping ability of the ProGlider glide path instrument (Dentsply Sirona). METHODOLOGY: Mesiobuccal and mesiolingual canals of mandibular molars were selected based on the canal volume, length, angle of curvature (25°-40°), and radius of curvature (4-8 mm) after micro-computed tomographic scanning. The samples were randomly assigned to four groups (n = 13, each) according to movement kinematics [continuous rotation (CR; 300 rpm), optimum torque reverse motion (OTR; 180° forward and 90° reverse when torque >0.4 N cm), time-dependent reciprocal motion (TmR; 180° forward and 90° reverse), and optimal glide path motion (OGP; a combination of 90° forward, 90° reverse, 90° forward, and 120° reverse)]. Instrumentation was performed with an automated root canal instrument and torque/force analysing device. Maximum torque/force values, canal volume changes, and canal-centring ratios at 1, 3, 5, and 7 mm were evaluated. Surface defects (pits, grooves, microcracks, blunt cutting edges, and disruption of cutting edges) and spiral distortion on the ProGlider instrument were scored at the tip and 5 mm short of the tip before and after five consecutive uses with scanning electron microscopy. The Kruskal-Wallis test followed by Dunn's post-test with Bonferroni correction and Wilcoxon signed-rank test were used to analyse the data (α = 0.05). RESULTS: Optimal glide path motion generated significantly less clockwise torque and greater upward force than other groups (p < .05). OGP resulted in significantly fewer surface defects than CR (p < .05). In OGP and CR, the tip exhibited more surface defects than 5 mm short of the tip (p < .05). CR resulted in greater volume changes than OGP and TmR (p < .05) and greater centring ratios (i.e., more deviation) than OGP at 1 mm and OTR at 3 mm (p < .05). CONCLUSIONS: Under laboratory conditions using the ProGlider instrument, OGP generated significantly less clockwise torque and greater upward force than the other rotatory motions. OGP generated fewer superficial defects than CR, and the three modes of reciprocal rotation better maintained the apical curvature of root canals than CR with the ProGlider instrument.


Assuntos
Níquel , Preparo de Canal Radicular , Fenômenos Biomecânicos , Cavidade Pulpar , Desenho de Equipamento , Titânio , Torque
4.
J Anim Ecol ; 89(9): 2122-2133, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32472576

RESUMO

Evidence-based management of natural populations under strong human influence frequently requires not only estimates of survival but also knowledge about how much mortality is due to anthropogenic vs. natural causes. This is the case particularly when individuals vary in their vulnerability to different causes of mortality due to traits, life history stages, or locations. Here, we estimated harvest and background (other cause) mortality of landlocked migratory salmonids over half a century. In doing so, we quantified among-individual variation in vulnerability to cause-specific mortality resulting from differences in body size and spawning location relative to a hydropower dam. We constructed a multistate mark-recapture model to estimate harvest and background mortality hazard rates as functions of a discrete state (spawning location) and an individual time-varying covariate (body size). We further accounted for among-year variation in mortality and migratory behaviour and fit the model to a unique 50-year time series of mark-recapture-recovery data on brown trout (Salmo trutta) in Norway. Harvest mortality was highest for intermediate-sized trout, and outweighed background mortality for most of the observed size range. Background mortality decreased with body size for trout spawning above the dam and increased for those spawning below. All vital rates varied substantially over time, but a trend was evident only in estimates of fishers' reporting rate, which decreased from over 50% to less than 10% throughout the study period. We highlight the importance of body size for cause-specific mortality and demonstrate how this can be estimated using a novel hazard rate parameterization for mark-recapture models. Our approach allows estimating effects of individual traits and environment on cause-specific mortality without confounding, and provides an intuitive way to estimate temporal patterns within and correlation among different mortality sources.


Assuntos
Truta , Animais , Tamanho Corporal , Causas de Morte , Noruega
5.
J Minim Access Surg ; 16(4): 335-340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929224

RESUMO

BACKGROUND: Since the advent of laparoscopic surgery, many studies have shown the advantages of laparoscopic surgery over open surgery for ventral hernia repair (VHR). As robotic surgery is gaining popularity, we sought to compare the outcomes of this newer robotic-assisted technique to the outcomes of established open and laparoscopic techniques to assess for any additional benefit. METHODS: A meta-analysis research design was employed. Multiple databases were queried for publications over the past 10 years and 23 articles were selected based on pre-determined selection criteria. Data were extracted and the arm-based network meta-analysis method was utilised to examine the effect difference for the three arms of our study: Open, laparoscopic and robotic-assisted VHR. RESULTS: As expected, laparoscopy had an advantage over open VHR in terms of infection rates. This advantage was also observed in the robotic group over the open group; however, there was no statistical difference between the laparoscopic and robotic groups when infection rates were compared head-to-head. The robotic group had a significant advantage over both the open and more importantly, the laparoscopic groups in recurrence rates. CONCLUSIONS: The results of this study suggest that robotic surgery maintains some of the advantages of laparoscopic surgery and may also provide the additional advantage of recurrence rate reduction. This may be explained by the ability to perform a more complex hernia repair with robotic assistance secondary to the ease of closure of the fascial defect. More research is needed to validate this finding.

6.
Osteoporos Int ; 30(8): 1693-1698, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069439

RESUMO

Interventions that alter PTH levels in an animal model of chronic kidney disease have effects on the perfusion of bone and bone marrow. INTRODUCTION: Patients with chronic kidney disease (CKD) have accelerated bone loss, vascular calcification, and abnormal biochemistries, together contributing to an increased risk of cardiovascular disease and fracture-associated mortality. Despite evidence of vascular pathologies and dysfunction in CKD, our group has shown that cortical bone tissue perfusion is higher in a rat model of high-turnover CKD. The goal of the present study was to test the hypothesis that parathyroid hormone (PTH) suppressive interventions would normalize cortical bone vascular perfusion in the setting of CKD. METHODS: In two separate experiments, 35-week-old CKD animals and their normal littermates underwent intra-cardiac fluorescent microsphere injection to assess the effect of 10 weeks of PTH suppression (Experiment 1: calcium supplementation, Experiment 2: calcimimetic treatment) on alterations in bone tissue perfusion. RESULTS: In Experiment 1, CKD animals had serum blood urea nitrogen (BUN) and PTH levels significantly higher than NL (+ 182% and + 958%; p < 0.05). CKD+Ca animals had BUN levels that were similar to CKD, while PTH levels were significantly lower and comparable to NL. Both femoral cortex (+ 220%, p = 0.003) and tibial cortex (+ 336, p = 0.005) tissue perfusion were significantly higher in CKD animals when compared to NL; perfusion was normalized to those of NL in CKD+Ca animals. MicroCT analysis of the proximal tibia cortical porosity showed a trend toward higher values in CKD (+ 401%; p = 0.017) but not CKD+Ca (+ 111%; p = 0.38) compared to NL. Experiment 2, using an alternative method of PTH suppression, showed similar results as those of Experiment 1. CONCLUSIONS: These data demonstrate that PTH suppression-based interventions normalize cortical bone perfusion in the setting of CKD.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/fisiopatologia , Osso Cortical/irrigação sanguínea , Hormônio Paratireóideo/antagonistas & inibidores , Insuficiência Renal Crônica/fisiopatologia , Animais , Nitrogênio da Ureia Sanguínea , Cálcio/farmacologia , Cálcio/uso terapêutico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/sangue , Distúrbio Mineral e Ósseo na Doença Renal Crônica/tratamento farmacológico , Suplementos Nutricionais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Masculino , Hormônio Paratireóideo/sangue , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Projetos Piloto , Porosidade , Ratos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/tratamento farmacológico , Microtomografia por Raio-X
7.
Lupus ; 28(7): 818-825, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31072277

RESUMO

OBJECTIVE: There is limited knowledge on the relative impact of lupus nephritis (LN) on morbidity and mortality in population-based systemic lupus erythematous (SLE) cohorts. Here, the primary aim was to compare mortality rates between patients with and without LN in a population-based SLE cohort. METHODS: The study cohort included all SLE patients resident in the city of Oslo during 1999-2008. Follow-up time was median 14 (0-15) years. Presence of LN was defined according to the 1987 American College of Rheumatology classification criteria for SLE. LN class was determined by renal biopsy. Data on kidney function, including presence of end-stage renal disease (ESRD), were obtained from patient charts. Standardized mortality ratios (SMRs) were estimated by comparing deaths in the SLE cohort with age- and gender-matched population controls. RESULTS: We found that 98/325 SLE patients (30%) developed LN, 92% of whom had occurrence within the first five years from disease onset. Incidence rate of ESRD was 2.3 per 1000 patient-years. A total of 56 deaths occurred during the study period, corresponding to an overall SMR in the SLE cohort of 2.1 (95% confidence interval (CI) 1.2-3.4). Estimated SMR for LN patients was 3.8 (95% CI 2.1-6.2), and for SLE patients without LN it was 1.7 (95% CI 0.9-2.7). CONCLUSION: In this population-based SLE cohort, we found that LN was associated with increased morbidity and mortality, whereas SLE patients who did not develop LN had good overall prognoses regarding survival.


Assuntos
Lúpus Eritematoso Sistêmico/mortalidade , Nefrite Lúpica/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Noruega/epidemiologia , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
8.
Ecology ; 99(5): 1011-1017, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29438578

RESUMO

Body size can have profound impacts on survival, movement, and reproductive schedules shaping individual fitness, making growth a central process in ecological and evolutionary dynamics. Realized growth is the result of a complex interplay between life history schedules, individual variation, and environmental influences. Integrating all of these aspects into growth models is methodologically difficult, depends on the availability of repeated measurements of identifiable individuals, and consequently represents a major challenge in particular for natural populations. Using a unique 30-yr time series of individual length measurements inferred from scale year rings of wild brown trout, we develop a Bayesian hierarchical model to estimate individual growth trajectories in temporally and spatially varying environments. We reveal a gradual decrease in average juvenile growth, which has carried over to adult life and contributed to decreasing sizes observed at the population level. Commonly studied environmental drivers like temperature and water flow did not explain much of this trend and overall persistent and among-year individual variation dwarfed temporal variation in growth patterns. Our model and results are relevant to a wide range of questions in ecology and evolution requiring a detailed understanding of growth patterns, including conservation and management of many size-structured populations.


Assuntos
Ecologia , Água Doce , Animais , Teorema de Bayes , Tamanho Corporal , Truta
9.
Osteoporos Int ; 29(9): 2139-2146, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29947866

RESUMO

This work examines the skeletal accumulation of fluorescently tagged zoledronate in an animal model of chronic kidney disease. The results show higher accumulation in 24-h post-dose animals with lower kidney function due to greater amounts of binding at individual surfaces. INTRODUCTION: Chronic kidney disease (CKD) patients suffer from increased rates of skeletal-related mortality from changes driven by biochemical abnormalities. Bisphosphonates are commonly used in reducing fracture risk in a variety of diseases, yet their use is not recommended in advanced stages of CKD. This study aimed to characterize the accumulation of a single dose of fluorescently tagged zoledronate (FAM-ZOL) in the setting of reduced kidney function. METHODS: At 25 weeks of age, FAM-ZOL was administered to normal and CKD rats. Twenty-four hours later, multiple bones were collected and assessed using bulk fluorescence imaging, two-photon imaging, and dynamic histomorphometry. RESULTS: CKD animals had significantly higher levels of FAM-ZOL accumulation in the proximal tibia, radius, and ulna, but not in lumbar vertebral body or mandible, based on multiple measurement modalities. Although a majority of trabecular bone surfaces were covered with FAM-ZOL in both normal and CKD animals, the latter had significantly higher levels of fluorescence per unit bone surface in the proximal tibia. CONCLUSIONS: These results provide new data regarding how reduced kidney function affects drug accumulation in rat bone.


Assuntos
Conservadores da Densidade Óssea/farmacocinética , Osso e Ossos/metabolismo , Insuficiência Renal Crônica/metabolismo , Ácido Zoledrônico/farmacocinética , Animais , Osso e Ossos/diagnóstico por imagem , Modelos Animais de Doenças , Masculino , Imagem Óptica/métodos , Ratos Endogâmicos , Tíbia/diagnóstico por imagem , Tíbia/metabolismo
10.
Glob Chang Biol ; 24(11): 5044-5055, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30005138

RESUMO

Blooms of cyanobacteria are a current threat to global water security that is expected to increase in the future because of increasing nutrient enrichment, increasing temperature and extreme precipitation in combination with prolonged drought. However, the responses to multiple stressors, such as those above, are often complex and there is contradictory evidence as to how they may interact. Here we used broad scale data from 494 lakes in central and northern Europe, to assess how cyanobacteria respond to nutrients (phosphorus), temperature and water retention time in different types of lakes. Eight lake types were examined based on factorial combinations of major factors that determine phytoplankton composition and sensitivity to nutrients: alkalinity (low and medium-high), colour (clear and humic) and mixing intensity (polymictic and stratified). In line with expectations, cyanobacteria increased with temperature and retention time in five of the eight lake types. Temperature effects were greatest in lake types situated at higher latitudes, suggesting that lakes currently not at risk could be affected by warming in the future. However, the sensitivity of cyanobacteria to temperature, retention time and phosphorus varied among lake types highlighting the complex responses of lakes to multiple stressors. For example, in polymictic, medium-high alkalinity, humic lakes cyanobacteria biovolume was positively explained by retention time and a synergy between TP and temperature, while in polymictic, medium-high alkalinity, clear lakes only retention time was identified as an explanatory variable. These results show that, although climate change will need to be accounted for when managing the risk of cyanobacteria in lakes, a "one-size fits-all" approach is not appropriate. When forecasting the response of cyanobacteria to future environmental change, including changes caused by climate and local management, it will be important to take this differential sensitivity of lakes into account.


Assuntos
Cianobactérias , Lagos/microbiologia , Mudança Climática , Meio Ambiente , Europa (Continente) , Fósforo/análise , Fitoplâncton
11.
Phys Rev Lett ; 116(16): 163601, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27152801

RESUMO

We demonstrate a laser using material defects known for deleterious microwave absorption in quantum computing. These defects are two-level atomic tunneling systems (TSs), which are manipulated using a uniform swept dc electric field and two ac pump fields. The swept field changes the TS energies. TSs first pass through degeneracy with pump photons, which invert (excite) them with a high probability using rapid adiabatic passage. Population inversion is accomplished in spite of a broad distribution of TS parameters. Afterwards the TSs are brought to degeneracy with the resonator where they emit photons. The emission is found to be dependent on individual cavity-TS interactions, and the narrowing linewidth at increasing photon occupancy indicates stimulated emission. Characterization with a microwave probe shows a transition from ordinary defect loss to negligible microwave absorption, and ultimately to coherent amplification. Thus, instead of absorbing microwave energy, the TSs can be tuned to reduce loss and even amplify signals.

12.
Osteoporos Int ; 26(3): 977-85, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25466530

RESUMO

UNLABELLED: Chronic kidney disease (CKD) increases fracture risk. The results of this work point to changes in bone collagen and bone hydration as playing a role in bone fragility associated with CKD. INTRODUCTION: Clinical data have documented a clear increase in fracture risk associated with chronic kidney disease (CKD). Preclinical studies have shown reductions in bone mechanical properties although the tissue-level mechanisms for these differences remain unclear. The goal of this study was to assess collagen cross-links and matrix hydration, two variables known to affect mechanical properties, in animals with either high- or low-turnover CKD. METHODS: At 35 weeks of age (>75% reduction in kidney function), the femoral diaphysis of male Cy/+ rats with high or low bone turnover rates, along with normal littermate (NL) controls, were assessed for collagen cross-links (pyridinoline (Pyd), deoxypyridinoline (Dpd), and pentosidine (PE)) using a high-performance liquid chromatography (HPLC) assay as well as pore and bound water per volume (pw and bw) using a (1)H nuclear magnetic resonance (NMR) technique. Material-level biomechanical properties were calculated based on previously published whole bone mechanical tests. RESULTS: Cortical bone from animals with high-turnover disease had lower Pyd and Dpd cross-link levels (-21% each), lower bw (-10%), higher PE (+71%), and higher pw (+46%) compared to NL. Animals with low turnover had higher Dpd, PE (+71%), and bw (+7%) along with lower pw (-60%) compared to NL. Both high- and low-turnover animals had reduced material-level bone toughness compared to NL animals as determined by three-point bending. CONCLUSIONS: These data document an increase in skeletal PE with advanced CKD that is independent of bone turnover rate and inversely related to decline in kidney function. Although hydration changes occur in both high- and low-turnover disease, the data suggest that nonenzymatic collagen cross-links may be a key factor in compromised mechanical properties of CKD.


Assuntos
Água Corporal/metabolismo , Matriz Óssea/metabolismo , Osso e Ossos/metabolismo , Colágeno/metabolismo , Insuficiência Renal Crônica/metabolismo , Aminoácidos/metabolismo , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Osso e Ossos/fisiopatologia , Diáfises/metabolismo , Modelos Animais de Doenças , Fêmur/metabolismo , Fêmur/fisiopatologia , Lisina/análogos & derivados , Lisina/metabolismo , Masculino , Ratos , Insuficiência Renal Crônica/fisiopatologia , Estresse Mecânico
13.
Osteoporos Int ; 26(6): 1801-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25701052

RESUMO

UNLABELLED: In aging, the bone marrow fills with fat and this may lead to higher fracture risk. We show that a bone marrow fat measurement by magnetic resonance spectroscopy (MRS), a newer technique not previously studied in chronic kidney disease (CKD), is useful and reproducible. CKD patients have significantly higher bone marrow fat than healthy adults. INTRODUCTION: Renal osteodystrophy leads to increased morbidity and mortality in patients with CKD. Traditional bone biopsy histomorphometry is used to study abnormalities in CKD, but the bone marrow, the source of osteoblasts, has not been well characterized in patients with CKD. METHODS: To determine the repeatability of bone marrow fat fraction assessment by MRS and water-fat imaging (WFI) at four sites in patients with CKD, testing was performed to determine the coefficients of reproducibility and intraclass coefficients (ICCs). We further determined if this noninvasive technique could be used to determine if there are differences in the percent bone marrow fat in patients with CKD compared to matched controls using paired t tests. RESULTS: The mean age of subjects with CKD was 59.8 ± 7.2 years, and the mean eGFR was 24 ± 8 ml/min. MRS showed good reproducibility at all sites in subjects with CKD and controls, with a coefficient of reproducibilities ranging from 2.4 to 13 %. MRS and WFI assessment of bone marrow fat showed moderate to strong agreement (ICC 0.6-0.7) at the lumbar spine, with poorer agreement at the iliac crest and no agreement at the tibia. The mean percent bone marrow fat at L2-L4 was 13.8 % (95 % CI 8.3-19.7) higher in CKD versus controls (p < 0.05). CONCLUSIONS: MRS is a useful and reproducible technique to study bone marrow fat in CKD. Patients with CKD have significantly higher bone marrow fat than healthy adults; the relationship with bone changes requires further analyses.


Assuntos
Tecido Adiposo/patologia , Medula Óssea/patologia , Insuficiência Renal Crônica/patologia , Idoso , Estudos de Casos e Controles , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/fisiopatologia , Feminino , Taxa de Filtração Glomerular , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/fisiopatologia , Reprodutibilidade dos Testes
14.
Integr Environ Assess Manag ; 20(5): 1715-1735, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38771172

RESUMO

Preparing for future environmental pressures requires projections of how relevant risks will change over time. Current regulatory models of environmental risk assessment (ERA) of pollutants such as pharmaceuticals could be improved by considering the influence of global change factors (e.g., population growth) and by presenting uncertainty more transparently. In this article, we present the development of a prototype object-oriented Bayesian network (BN) for the prediction of environmental risk for six high-priority pharmaceuticals across 36 scenarios: current and three future population scenarios, combined with infrastructure scenarios, in three Norwegian counties. We compare the risk, characterized by probability distributions of risk quotients (RQs), across scenarios and pharmaceuticals. Our results suggest that RQs would be greatest in rural counties, due to the lower development of current wastewater treatment facilities, but that these areas consequently have the most potential for risk mitigation. This pattern intensifies under higher population growth scenarios. With this prototype, we developed a hierarchical probabilistic model and demonstrated its potential in forecasting the environmental risk of chemical stressors under plausible demographic and management scenarios, contributing to the further development of BNs for ERA. Integr Environ Assess Manag 2024;20:1715-1735. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Monitoramento Ambiental , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Medição de Risco , Águas Residuárias/química , Poluentes Químicos da Água/análise , Preparações Farmacêuticas/análise , Monitoramento Ambiental/métodos , Teorema de Bayes , Noruega , Modelos Estatísticos
15.
Integr Environ Assess Manag ; 20(2): 401-418, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38018499

RESUMO

An understanding of the combined effects of climate change (CC) and other anthropogenic stressors, such as chemical exposures, is essential for improving ecological risk assessments of vulnerable ecosystems. In the Great Barrier Reef, coral reefs are under increasingly severe duress from increasing ocean temperatures, acidification, and cyclone intensities associated with CC. In addition to these stressors, inshore reef systems, such as the Mackay-Whitsunday coastal zone, are being impacted by other anthropogenic stressors, including chemical, nutrient, and sediment exposures related to more intense rainfall events that increase the catchment runoff of contaminated waters. To illustrate an approach for incorporating CC into ecological risk assessment frameworks, we developed an adverse outcome pathway network to conceptually delineate the effects of climate variables and photosystem II herbicide (diuron) exposures on scleractinian corals. This informed the development of a Bayesian network (BN) to quantitatively compare the effects of historical (1975-2005) and future projected climate on inshore hard coral bleaching, mortality, and cover. This BN demonstrated how risk may be predicted for multiple physical and biological stressors, including temperature, ocean acidification, cyclones, sediments, macroalgae competition, and crown of thorns starfish predation, as well as chemical stressors such as nitrogen and herbicides. Climate scenarios included an ensemble of 16 downscaled models encompassing current and future conditions based on multiple emission scenarios for two 30-year periods. It was found that both climate-related and catchment-related stressors pose a risk to these inshore reef systems, with projected increases in coral bleaching and coral mortality under all future climate scenarios. This modeling exercise can support the identification of risk drivers for the prioritization of management interventions to build future resilient reefs. Integr Environ Assess Manag 2024;20:401-418. © 2023 Norwegian Institute for Water Research and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Antozoários , Recifes de Corais , Humanos , Animais , Ecossistema , Mudança Climática , Teorema de Bayes , Concentração de Íons de Hidrogênio , Água do Mar , Austrália
16.
Environ Toxicol Chem ; 43(1): 182-196, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37750580

RESUMO

Bayesian network (BN) models are increasingly used as tools to support probabilistic environmental risk assessments (ERAs), because they can better account for uncertainty compared with the simpler approaches commonly used in traditional ERA. We used BNs as metamodels to link various sources of information in a probabilistic framework, to predict the risk of pesticides to aquatic communities under given scenarios. The research focused on rice fields surrounding the Albufera Natural Park (Valencia, Spain), and considered three selected pesticides: acetamiprid (an insecticide), 2-methyl-4-chlorophenoxyacetic acid (MCPA; a herbicide), and azoxystrobin (a fungicide). The developed BN linked the inputs and outputs of two pesticide models: a process-based exposure model (Rice Water Quality [RICEWQ]), and a probabilistic effects model (Predicts the Ecological Risk of Pesticides [PERPEST]) using case-based reasoning with data from microcosm and mesocosm experiments. The model characterized risk at three levels in a hierarchy: biological endpoints (e.g., molluscs, zooplankton, insects, etc.), endpoint groups (plants, invertebrates, vertebrates, and community processes), and community. The pesticide risk to a biological endpoint was characterized as the probability of an effect for a given pesticide concentration interval. The risk to an endpoint group was calculated as the joint probability of effect on any of the endpoints in the group. Likewise, community-level risk was calculated as the joint probability of any of the endpoint groups being affected. This approach enabled comparison of risk to endpoint groups across different pesticide types. For example, in a scenario for the year 2050, the predicted risk of the insecticide to the community (40% probability of effect) was dominated by the risk to invertebrates (36% risk). In contrast, herbicide-related risk to the community (63%) resulted from risk to both plants (35%) and invertebrates (38%); the latter might represent (in the present study) indirect effects of toxicity through the food chain. This novel approach combines the quantification of spatial variability of exposure with probabilistic risk prediction for different components of aquatic ecosystems. Environ Toxicol Chem 2024;43:182-196. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Herbicidas , Inseticidas , Oryza , Praguicidas , Poluentes Químicos da Água , Animais , Praguicidas/toxicidade , Praguicidas/análise , Inseticidas/toxicidade , Ecossistema , Teorema de Bayes , Invertebrados , Medição de Risco/métodos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
17.
Integr Environ Assess Manag ; 20(2): 384-400, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37795750

RESUMO

Global climate change will significantly impact the biodiversity of freshwater ecosystems, both directly and indirectly via the exacerbation of impacts from other stressors. Pesticides form a prime example of chemical stressors that are expected to synergize with climate change. Aquatic exposures to pesticides might change in magnitude due to increased runoff from agricultural fields, and in composition, as application patterns will change due to changes in pest pressures and crop types. Any prospective chemical risk assessment that aims to capture the influence of climate change should properly and comprehensively account for the variabilities and uncertainties that are inherent to projections of future climate. This is only feasible if they probabilistically propagate extensive ensembles of climate model projections. However, current prospective risk assessments typically make use of process-based models of chemical fate that do not typically allow for such high-throughput applications. Here, we describe a Bayesian network model that does. It incorporates a two-step univariate regression model based on a 30-day antecedent precipitation index, circumventing the need for computationally laborious mechanistic models. We show its feasibility and application potential in a case study with two pesticides in a Norwegian stream: the fungicide trifloxystrobin and herbicide clopyralid. Our analysis showed that variations in pesticide application rates as well as precipitation intensity lead to variations in in-stream exposures. When relating to aquatic risks, the influence of these processes is reduced and distributions of risk are dominated by effect-related parameters. Predicted risks for clopyralid were negligible, but the probability of unacceptable future environmental risks due to exposure to trifloxystrobin (i.e., a risk quotient >1) was 8%-12%. This percentage further increased to 30%-35% when a more conservative precautionary factor of 100 instead of 30 was used. Integr Environ Assess Manag 2024;20:384-400. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Acetatos , Iminas , Praguicidas , Estrobilurinas , Praguicidas/análise , Ecossistema , Teorema de Bayes , Medição de Risco
18.
Environ Toxicol Chem ; 43(3): 559-574, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36722131

RESUMO

In 2012, 20 key questions related to hazard and exposure assessment and environmental and health risks of pharmaceuticals and personal care products in the natural environment were identified. A decade later, this article examines the current level of knowledge around one of the lowest-ranking questions at that time, number 19: "Can nonanimal testing methods be developed that will provide equivalent or better hazard data compared with current in vivo methods?" The inclusion of alternative methods that replace, reduce, or refine animal testing within the regulatory context of risk and hazard assessment of chemicals generally faces many hurdles, although this varies both by organism (human-centric vs. other), sector, and geographical region or country. Focusing on the past 10 years, only works that might reasonably be considered to contribute to advancements in the field of aquatic environmental risk assessment are highlighted. Particular attention is paid to methods of contemporary interest and importance, representing progress in (1) the development of methods which provide equivalent or better data compared with current in vivo methods such as bioaccumulation, (2) weight of evidence, or (3) -omic-based applications. Evolution and convergence of these risk assessment areas offer the basis for fundamental frameshifts in how data are collated and used for the protection of taxa across the breadth of the aquatic environment. Looking to the future, we are at a tipping point, with a need for a global and inclusive approach to establish consensus. Bringing together these methods (both new and old) for regulatory assessment and decision-making will require a concerted effort and orchestration. Environ Toxicol Chem 2024;43:559-574. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Ecotoxicologia , Meio Ambiente , Animais , Humanos , Ecotoxicologia/métodos , Medição de Risco/métodos
19.
IJTLD Open ; 1(8): 344-348, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39131592

RESUMO

BACKGROUND: The rate of TB in prison institutions is estimated to be 23 times higher than in the general population. Limited documentation exists regarding TB screening in Tajikistan's prisons. This study aims to report findings from a TB screening conducted in prison facilities in Tajikistan. METHODS: A systematic TB screening was conducted between July 2022 and September 2023, following a locally adapted algorithm based on WHO recommendations. The screening yield was calculated as the proportion of confirmed TB cases, with categorical variables compared using a χ2 test. RESULTS: A total of 7,223 screenings were conducted, identifying 31 TB cases, including 17 drug-susceptible TB cases, eight drug-resistant TB cases, and six clinically diagnosed cases. The overall screening yield was 0.43%. Notably, the screening yield was 3.4% among individuals with at least one TB symptom and 0.03% among those without TB symptoms (P < 0.001). CONCLUSION: The identified rate of TB in these prisons is five times higher than in the general population. Symptomatic individuals had a higher likelihood of TB diagnosis, and using chest X-rays significantly improved screening yield. We recommend increasing the capacity for chest X-ray testing to enhance TB prevention and control within prison settings.


CONTEXTE: On estime que le taux de TB dans les établissements pénitentiaires est 23 fois plus élevé que dans la population générale. Il existe peu de documentation sur le dépistage de la TB dans les prisons du Tadjikistan. Cette étude vise à rendre compte des résultats d'un dépistage de la TB mené dans des établissements pénitentiaires au Tadjikistan. MÉTHODES: Un dépistage systématique de la TB a été réalisé entre juillet 2022 et septembre 2023, selon un algorithme adapté localement et basé sur les recommandations de l'OMS. Le rendement du dépistage a été calculé comme la proportion de cas confirmés de TB, avec des variables catégorielles comparées à l'aide d'un test χ2. RÉSULTATS: Au total, 7 223 dépistages ont été effectués, permettant d'identifier 31 cas de TB, dont 17 cas de TB sensible aux médicaments, 8 cas de TB résistante aux médicaments et 6 cas diagnostiqués cliniquement. Le rendement global du criblage était de 0,43%. Notamment, le rendement du dépistage était de 3,4% chez les personnes présentant au moins un symptôme de la TB et de 0,03% chez celles ne présentant pas de symptômes de la TB (P < 0,001). CONCLUSION: Le taux de TB identifié dans ces prisons est cinq fois plus élevé que dans la population générale. Les personnes symptomatiques avaient une probabilité plus élevée d'être diagnostiquées comme atteintes de TB, et l'utilisation de radiographies pulmonaires améliorait considérablement le rendement du dépistage. Nous recommandons d'augmenter la capacité de dépistage par radiographie thoracique afin d'améliorer la prévention et le contrôle de la TB en milieu carcéral.

20.
Integr Environ Assess Manag ; 20(2): 359-366, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38124219

RESUMO

The impacts of global climate change are not yet well integrated with the estimates of the impacts of chemicals on the environment. This is evidenced by the lack of consideration in national or international reports that evaluate the impacts of climate change and chemicals on ecosystems and the relatively few peer-reviewed publications that have focused on this interaction. In response, a 2011 Pellston Workshop® was held on this issue and resulted in seven publications in Environmental Toxicology and Chemistry. Yet, these publications did not move the field toward climate change and chemicals as important factors together in research or policy-making. Here, we summarize the outcomes of a second Pellston Workshop® on this topic held in 2022 that included climate scientists, environmental toxicologists, chemists, and ecological risk assessors from 14 countries and various sectors. Participants were charged with assessing where climate models can be applied to evaluating potential exposure and ecological effects at geographical and temporal scales suitable for ecological risk assessment, and thereby be incorporated into adaptive risk management strategies. We highlight results from the workshop's five publications included in the special series "Incorporating Global Climate Change into Ecological Risk Assessments: Strategies, Methods and Examples." We end this summary with the overall conclusions and recommendations from participants. Integr Environ Assess Manag 2024;20:359-366. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Poluentes Ambientais , Humanos , Poluentes Ambientais/análise , Ecossistema , Modelos Climáticos , Mudança Climática , Ecotoxicologia , Medição de Risco/métodos , Gestão de Riscos
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