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1.
Mar Pollut Bull ; 202: 116393, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669855

RESUMO

Microplastics (MP) are found in marine sediments across the globe, but we are just beginning to understand their spatial distribution and assemblages. In this study, we quantified MP in Gulf of Maine, USA sediments. MP were extracted from 20 sediment samples, followed by polymer identification using Raman spectroscopy. We detected 27 polymer types and 1929 MP kg-1 wet sediment, on average. Statistical analyses showed that habitat, hydrodynamics, and station proximity were more important drivers of MP assemblages than land use or sediment characteristics. Stations closer to one another were more similar in their MP assemblages, tidal rivers had higher numbers of unique plastic polymers than open water or embayment stations, and stations closer to shore had higher numbers of MP. There was little evidence of relationships between MP assemblages and land use, sediment texture, total organic carbon, or contaminants.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Hidrodinâmica , Microplásticos , Poluentes Químicos da Água , Sedimentos Geológicos/química , Maine , Microplásticos/análise , Poluentes Químicos da Água/análise
2.
Eur Heart J Open ; 4(2): oeae025, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38659665

RESUMO

Aims: Aging-related cardiovascular disease and frailty burdens are anticipated to rise with global aging. In response to directions from major cardiovascular societies, we investigated frailty knowledge, awareness, and practices among cardiologists as key stakeholders in this emerging paradigm a year after the European Frailty in Cardiology consensus document was published. Methods and results: We launched a prospective multinational web-based survey via social networks to broad cardiology communities representing multiple World Health Organization regions, including Western Pacific and Southeast Asia regions. Overall, 578 respondents [38.2% female; ages 35-49 years (55.2%) and 50-64 years (34.4%)] across subspecialties, including interventionists (43.3%), general cardiologists (30.6%), and heart failure specialists (HFSs) (10.9%), were surveyed. Nearly half had read the consensus document (38.9%). Non-interventionists had better perceived knowledge of frailty assessment instruments (fully or vaguely aware, 57.2% vs. 45%, adj. P = 0.0002), exercise programmes (well aware, 12.9% vs. 6.0%, adj. P = 0.001), and engaged more in multidisciplinary team care (frequently or occasionally, 52.6% vs. 41%, adj. P = 0.002) than interventionists. Heart failure specialists more often addressed pre-procedural frailty (frequently or occasionally, 43.5% vs. 28.2%, P = 0.004) and polypharmacy (frequently or occasionally, 85.5% vs. 71%, adj. P = 0.014) and had consistently better composite knowledge (39.3% vs. 21.6%, adj. P = 0.001) and practice responses (21% vs. 11.1%, adj. P = 0.018) than non-HFSs. Respondents with better knowledge responses also had better frailty practices (40.3% vs. 3.6%, adj. P < 0.001). Conclusion: Distinct response differences suggest that future strategies strengthening frailty principles should address practices peculiar to subspecialties, such as pre-procedural frailty strategies for interventionists and rehabilitation interventions for HFSs.

3.
Sci Total Environ ; 927: 171153, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460683

RESUMO

About 3 billion new tires are produced each year and about 800 million tires become waste annually. Global dependence upon tires produced from natural rubber and petroleum-based compounds represents a persistent and complex environmental problem with only partial and often-times, ineffective solutions. Tire emissions may be in the form of whole tires, tire particles, and chemical compounds, each of which is transported through various atmospheric, terrestrial, and aquatic routes in the natural and built environments. Production and use of tires generates multiple heavy metals, plastics, PAH's, and other compounds that can be toxic alone or as chemical cocktails. Used tires require storage space, are energy intensive to recycle, and generally have few post-wear uses that are not also potential sources of pollutants (e.g., crumb rubber, pavements, burning). Tire particles emitted during use are a major component of microplastics in urban runoff and a source of unique and highly potent toxic substances. Thus, tires represent a ubiquitous and complex pollutant that requires a comprehensive examination to develop effective management and remediation. We approach the issue of tire pollution holistically by examining the life cycle of tires across production, emissions, recycling, and disposal. In this paper, we synthesize recent research and data about the environmental and human health risks associated with the production, use, and disposal of tires and discuss gaps in our knowledge about fate and transport, as well as the toxicology of tire particles and chemical leachates. We examine potential management and remediation approaches for addressing exposure risks across the life cycle of tires. We consider tires as pollutants across three levels: tires in their whole state, as particulates, and as a mixture of chemical cocktails. Finally, we discuss information gaps in our understanding of tires as a pollutant and outline key questions to improve our knowledge and ability to manage and remediate tire pollution.

4.
AsiaIntervention ; 10(1): 51-59, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38425806

RESUMO

Background: The use of cerebral embolic protection devices during transcatheter aortic valve implantation (TAVI) reveals conflicting data. Aims: This updated meta-analysis aims to evaluate the efficacy and safety of the SENTINEL Cerebral Protection System. Methods: A literature search for relevant studies up to September 2022 was performed. Study outcomes were divided based on time period - overall (up to 30 days) and short (≤7 days). The outcomes studied include stroke (disabling, non-disabling), mortality, neuroimaging findings, transient ischaemic attack, acute kidney injury and major vascular and bleeding complications. Results: A total of 15 studies involving 294,134 patients were included. Regarding overall outcomes, significant reductions were noted for mortality (odds ratio [OR] 0.60, 95% confidence interval [CI]: 0.41-0.88; p=0.008), all stroke (OR 0.64, 95% CI: 0.46-0.88; p=0.006) and disabling stroke (OR 0.42, 95% CI: 0.23-0.74; p=0.003) using the SENTINEL device. No significant differences were noted for other outcomes. There was significant heterogeneity across the studies for mortality (p=0.013) and all stroke (p=0.003). Including only randomised data (n=4), there was only significant reduction in the incidence of disabling stroke (OR 0.39, 95% CI: 0.17-0.89; p=0.026) in the SENTINEL group. In studies reporting ≤7-day outcomes (n=8), use of the SENTINEL device demonstrated significantly lower rates of all stroke (p<0.001), disabling stroke (p<0.001) and major bleeding complications (p=0.02). No differences in neuroimaging outcomes were noted. Conclusions: In this updated meta-analysis, use of the SENTINEL Cerebral Protection System was associated with lower rates of mortality, all stroke and disabling stroke, although significant heterogeneity was noted for mortality and all stroke. Including exclusively randomised data, there was only significant reduction in the incidence of disabling stroke. No significant adverse outcomes with device use were noted.

6.
Environ Pollut ; 338: 122650, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37777055

RESUMO

Plastic particles are ubiquitous in marine systems and fragment into smaller pieces, such as nanoplastics (NPs). The effects of NPs on marine organisms are of growing concern but are not well understood. Marine sediments act as a sink for many contaminants, like microplastics, and are rich habitats for benthic micro- and meiofauna which are ecologically-important components of marine food webs; however, little is known about the sensitivities of specific organisms to NPs or the effects on community diversity and composition. Utilizing molecular methods, such as metabarcoding of environmental DNA/RNA, allows for the rapid and comprehensive detection of microscopic organisms via high-throughput sequencing to assess adverse effects at the community level. The objective of this study was to use a metabarcoding approach to investigate the effects of NPs on benthic micro- and meiofaunal community diversity. Mesocosms were created with sediment cores collected from the Narrow River estuary (Rhode Island, USA) and exposed to 900 nm diameter weathered polystyrene beads at concentrations of 0.1, 1, 10, or 100 mg/kg dry weight in sediment for two weeks. Following exposure, RNA and DNA were co-extracted from the sediment, RNA was reverse-transcribed, 18S and COI markers were PCR-amplified, and amplicons were sequenced on an Illumina MiSeq. Using the 18S marker and eRNA template, increases to α-diversity and significant differences to ß-diversity were observed in the highest NP exposures relative to the control. Observed differences in community composition were driven by the differential abundance of several types of protists and arthropods. Significant dose-dependent shifts in composition were observed in ß-diversity Jaccard and Unweighted-Unifrac metrics with the 18S marker using the RNA template. To our knowledge, this is the first demonstration of a dose-response relationship for NPs at a community level, and it highlights the value of using community-level endpoints to assess environmental impacts of nanoparticles.


Assuntos
DNA Ambiental , Ecossistema , Microplásticos , Biodiversidade , Plásticos/toxicidade , Código de Barras de DNA Taxonômico , RNA
7.
Am J Cardiol ; 205: 369-378, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37639763

RESUMO

Patients with chronic kidney disease (CKD) have traditionally been excluded from randomized trials. We aimed to compare percutaneous coronary intervention versus conservative management, and early intervention (EI; within 24 hours of admission) versus delayed intervention (DI; after 24 to 72 hours of admission) in patients with non-ST-segment elevation myocardial infarction (NSTEMI) and concomitant CKD. An electronic literature search was performed to search for studies comparing invasive management to conservative management or EI versus DI in patients with NSTEMI with CKD. The primary outcome was all-cause mortality; secondary outcomes were acute kidney injury (AKI) or dialysis, major bleeding, and recurrent MI. Hazard ratios (HRs) for the primary outcome and odds ratios for secondary outcomes were pooled in random-effects meta-analyses. Eleven studies (140,544 patients) were analyzed. Invasive management was associated with lower mortality than conservative management (HR 0.62, 95% confidence interval 0.57 to 0.67, p <0.001, I2 = 47%), with consistent benefit across all CKD stages, except CKD 5. There was no significant mortality difference between EI and DI, but subgroup analyses showed significant benefit for EI in stage 1 to 2 CKD (HR 0.75, 95% confidence interval 0.58 to 0.97, p = 0.03, I2 = 0%), with no significant difference in stage 3 and 4 to 5 CKD. Invasive strategy was associated with higher odds of AKI or dialysis and major bleeding, but lower odds of recurrent MI compared with conservative management. In conclusion, in patients with NSTEMI and CKD, an invasive strategy is associated with significant mortality benefit over conservative management in most patients with CKD, but at the expense of higher risk of AKI and bleeding. EI appears to benefit those with early stages of CKD. Trial Registration: PROSPERO CRD42023405491.


Assuntos
Injúria Renal Aguda , Infarto do Miocárdio sem Supradesnível do Segmento ST , Insuficiência Renal Crônica , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio sem Supradesnível do Segmento ST/complicações , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Tratamento Conservador , Hospitalização , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia
9.
Chemosphere ; 333: 138883, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37169088

RESUMO

Quality assurance and quality control (QA/QC) techniques are critical to analytical chemistry, and thus the analysis of microplastics. Procedural blanks are a key component of QA/QC for quantifying and characterizing background contamination. Although procedural blanks are becoming increasingly common in microplastics research, how researchers acquire a blank and report and/or use blank contamination data varies. Here, we use the results of laboratory procedural blanks from a method evaluation study to inform QA/QC procedures for microplastics quantification and characterization. Suspected microplastic contamination in the procedural blanks, collected by 12 participating laboratories, had between 7 and 511 particles, with a mean of 80 particles per sample (±SD 134). The most common color and morphology reported were black fibers, and the most common size fraction reported was 20-212 µm. The lack of even smaller particles is likely due to limits of detection versus lack of contamination, as very few labs reported particles <20 µm. Participating labs used a range of QA/QC techniques, including air filtration, filtered water, and working in contained/'enclosed' environments. Our analyses showed that these procedures did not significantly affect blank contamination. To inform blank subtraction, several subtraction methods were tested. No clear pattern based on total recovery was observed. Despite our results, we recommend commonly accepted procedures such as thorough training and cleaning procedures, air filtration, filtered water (e.g., MilliQ, deionized or reverse osmosis), non-synthetic clothing policies and 'enclosed' air flow systems (e.g., clean cabinet). We also recommend blank subtracting by a combination of particle characteristics (color, morphology and size fraction), as it likely provides final microplastic particle characteristics that are most representative of the sample. Further work should be done to assess other QA/QC parameters, such as the use of other types of blanks (e.g., field blanks, matrix blanks) and limits of detection and quantification.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/análise , Laboratórios , Controle de Qualidade , Água/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise
10.
Mar Pollut Bull ; 192: 115073, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37245322

RESUMO

A common method for characterizing microplastics (MPs) involves capturing the plastic particles on a filter after extraction and isolation from the sediment particles. Microplastics captured on the filter are then scanned with Raman spectroscopy for polymer identification and quantification. However, scanning the whole filter manually using Raman analysis is a labor-intensive and time-consuming process. This study investigates a subsampling method for Raman spectroscopic analysis of microplastics (operationally defined here as 45-1000 µm in size) present in sediments and isolated onto laboratory filters. The method was evaluated using spiked MPs in deionized water and two environmentally contaminated sediments. Based on statistical analyses, we found quantification of a sub-fraction of 12.5 % of the filter in a wedge form was optimal, efficient, and accurate for estimating the entire filter count. The extrapolation method was then used to assess microplastic contamination in sediments from different marine regions of the United States.


Assuntos
Microplásticos , Poluentes Químicos da Água , Microplásticos/análise , Plásticos/análise , Análise Espectral Raman , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos/química
11.
Chemosphere ; 334: 138875, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37187379

RESUMO

Previous studies have evaluated method performance for quantifying and characterizing microplastics in clean water, but little is known about the efficacy of procedures used to extract microplastics from complex matrices. Here we provided 15 laboratories with samples representing four matrices (i.e., drinking water, fish tissue, sediment, and surface water) each spiked with a known number of microplastic particles spanning a variety of polymers, morphologies, colors, and sizes. Percent recovery (i.e., accuracy) in complex matrices was particle size dependent, with ∼60-70% recovery for particles >212 µm, but as little as 2% recovery for particles <20 µm. Extraction from sediment was most problematic, with recoveries reduced by at least one-third relative to drinking water. Though accuracy was low, the extraction procedures had no observed effect on precision or chemical identification using spectroscopy. Extraction procedures greatly increased sample processing times for all matrices with the extraction of sediment, tissue, and surface water taking approximately 16, 9, and 4 times longer than drinking water, respectively. Overall, our findings indicate that increasing accuracy and reducing sample processing times present the greatest opportunities for method improvement rather than particle identification and characterization.


Assuntos
Água Potável , Poluentes Químicos da Água , Animais , Microplásticos , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental
12.
Am J Cardiol ; 195: 45-56, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37011554

RESUMO

The landscape of aortic valve replacement (AVR) has evolved dramatically over the years, but time-varying outcomes have yet to be comprehensively explored. This study aimed to compare the all-cause mortality among 3 AVR techniques: transcatheter (TAVI), minimally invasive (MIAVR), and conventional AVR (CAVR). An electronic literature search was performed for randomized controlled trials (RCTs) comparing TAVI with CAVR and RCTs or propensity score-matched (PSM) studies comparing MIAVR with CAVR or MIAVR to TAVI. Individual patient data for all-cause mortality were derived from graphical reconstruction of Kaplan-Meier curves. Pairwise comparisons and network meta-analysis were conducted. Sensitivity analyses were performed in the TAVI arm for high risk and low/intermediate risk, as well as patients who underwent transfemoral (TF) TAVI. A total of 27 studies with 16,554 patients were included. In the pairwise comparisons, TAVI showed superior mortality to CAVR until 37.5 months, beyond which there was no significant difference. When restricted to TF TAVI versus CAVR, a consistent mortality benefit favoring TF TAVI was seen (shared frailty hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.76 to 0.98, p = 0.024). In the network meta-analysis involving majority PSM data, MIAVR demonstrated significantly lower mortality than TAVI (HR = 0.70, 95% CI = 0.59 to 0.82) and CAVR (HR = 0.69, 95% CI = 0.59 to 0.80); this association remained compared with TF TAVI but with a lower extent of benefit (HR = 0.80, 95% CI = 0.65 to 0.99). In conclusion, the initial short- to medium-term mortality benefit for TAVI over CAVR was attenuated over the longer term. In the subset of patients who underwent TF TAVI, a consistent benefit was found. Among majority PSM data, MIAVR showed improved mortality compared with TAVI and CAVR but less than the TF TAVI subset, which requires validation by robust RCTs.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Valva Aórtica/cirurgia , Metanálise em Rede , Estenose da Valva Aórtica/cirurgia , Resultado do Tratamento
13.
Chemosphere ; 313: 137479, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36513195

RESUMO

Microplastics (MP) are distributed throughout ecosystems and settle into sediments where they may threaten benthic communities; however, methods for quantifying MP in sediments have not been standardized. This study compares two methods for analyzing MP in sediments, including extraction and identification, and provides recommendations for improvement. Two laboratories processed sediment samples using two methods, referred to as "core" and "augmentation", and identified particles with visual microscopy and spectroscopy. Using visual microscopy, the augmentation method yielded mean recoveries (78%) significantly greater than the core (47%) (p = 0.03), likely due to the use of separatory funnels in the former. Spectroscopic recovery of particles was lower at 42 and 54% for the core and augmentation methods, respectively. We suspect the visual identification recoveries are overestimations from erroneous identification of non-plastic materials persisting post-extraction, indicating visual identification alone is not an accurate method to identify MP, particularly in complex matrices like sediment. However, both Raman and FTIR proved highly accurate at identifying recovered MP, with 96.7% and 99.8% accuracy, respectively. Low spectroscopic recovery of spiked particles indicates that MP recovery from sediments is lower than previously assumed, and MP may be more abundant in sediments than current analyses suggest. To our knowledge, likely due to the excessive time/labor-intensity associated with MP analyses, this is the first interlaboratory study to quantify complete method performance (extraction, identification) for sediments, with regards to capabilities and limitations. This is essential as regulatory bodies move toward long-term environmental MP monitoring.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Ecossistema , Microplásticos/análise , Plásticos , Monitoramento Ambiental/métodos
14.
Ann Acad Med Singap ; 51(10): 605-618, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36317571

RESUMO

INTRODUCTION: Data on patients with small aortic annuli (SAA) undergoing transcatheter aortic valve implantation (TAVI) are limited. We aim to describe the impact of aortic annular size, particularly SAA and TAVI valve type on valve haemodynamics, durability and clinical outcomes. METHOD: All patients in National Heart Centre Singapore who underwent transfemoral TAVI for severe symptomatic native aortic stenosis from July 2012 to December 2019 were included. Outcome measures include valve haemodynamics, prosthesis-patient mismatch (PPM), structural valve degeneration (SVD) and mortality. RESULTS: A total of 244 patients were included. The mean Society of Thoracic Surgeons score was 6.22±6.08, with 52.5% patients with small aortic annulus (<23mm), 33.2% patients with medium aortic annulus (23-26mm) and 14.3% patients with large aortic annulus (>26mm). There were more patients with self-expanding valve (SEV) (65.2%) versus balloon-expandable valve (BEV) (34.8%). There were no significant differences in indexed aortic valve area (iAVA), mean pressure gradient (MPG), PPM, SVD or mortality across all aortic annular sizes. However, specific to the SAA group, patients with SEV had larger iAVA (SEV 1.19±0.35cm2/m2 vs BEV 0.88±0.15cm2/m2, P<0.01) and lower MPG (SEV 9.25±4.88 mmHg vs BEV 14.17±4.75 mmHg, P<0.01) at 1 year, without differences in PPM or mortality. Aortic annular size, TAVI valve type and PPM did not predict overall mortality up to 7 years. There was no significant difference in SVD between aortic annular sizes up to 5 years. CONCLUSION: Valve haemodynamics and durability were similar across the different aortic annular sizes. In the SAA group, SEV had better haemodynamics than BEV at 1 year, but no differences in PPM or mortality. There were no significant differences in mortality between aortic annular sizes, TAVI valve types or PPM.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Desenho de Prótese , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento , Hemodinâmica
15.
Sci Rep ; 12(1): 17782, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273070

RESUMO

Microscopic organisms are often overlooked in traditional diversity assessments due to the difficulty of identifying them based on morphology. Metabarcoding is a method for rapidly identifying organisms where Environmental DNA (eDNA) is used as a template. However, legacy DNA is problematically detected from organisms no longer in the environment during sampling. Environmental RNA (eRNA), which is only produced by living organisms, can also be collected from environmental samples and used for metabarcoding. The aim of this study was to determine differences in community composition and diversity between eRNA and eDNA templates for metabarcoding. Using mesocosms containing field-collected communities from an estuary, RNA and DNA were co-extracted from sediment, libraries were prepared for two loci (18S and COI), and sequenced using an Illumina MiSeq. Results show a higher number of unique sequences detected from eRNA in both markers and higher α-diversity compared to eDNA. Significant differences between eRNA and eDNA for all ß-diversity metrics were also detected. This study is the first to demonstrate community differences detected with eRNA compared to eDNA from an estuarine system and illustrates the broad applications of eRNA as a tool for assessing benthic community diversity, particularly for environmental conservation and management applications.


Assuntos
DNA Ambiental , DNA Ambiental/genética , Código de Barras de DNA Taxonômico/métodos , RNA/genética , Monitoramento Ambiental/métodos , Biodiversidade , DNA/genética
16.
Chemosphere ; 308(Pt 3): 136449, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115477

RESUMO

Microscopy is often the first step in microplastic analysis and is generally followed by spectroscopy to confirm material type. The value of microscopy lies in its ability to provide count, size, color, and morphological information to inform toxicity and source apportionment. To assess the accuracy and precision of microscopy, we conducted a method evaluation study. Twenty-two laboratories from six countries were provided three blind spiked clean water samples and asked to follow a standard operating procedure. The samples contained a known number of microplastics with different morphologies (fiber, fragment, sphere), colors (clear, white, green, blue, red, and orange), polymer types (PE, PS, PVC, and PET), and sizes (ranging from roughly 3-2000 µm), and natural materials (natural hair, fibers, and shells; 100-7000 µm) that could be mistaken for microplastics (i.e., false positives). Particle recovery was poor for the smallest size fraction (3-20 µm). Average recovery (±StDev) for all reported particles >50 µm was 94.5 ± 56.3%. After quality checks, recovery for >50 µm spiked particles was 51.3 ± 21.7%. Recovery varied based on morphology and color, with poorest recovery for fibers and the largest deviations for clear and white particles. Experience mattered; less experienced laboratories tended to report higher concentration and had a higher variance among replicates. Participants identified opportunity for increased accuracy and precision through training, improved color and morphology keys, and method alterations relevant to size fractionation. The resulting data informs future work, constraining and highlighting the value of microscopy for microplastics.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Humanos , Microscopia , Plásticos/análise , Polímeros , Cloreto de Polivinila/análise , Água/análise , Poluentes Químicos da Água/análise
17.
BMC Health Serv Res ; 22(1): 994, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927703

RESUMO

OBJECTIVE: The objective was to assess the cost-effectiveness of transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis with intermediate surgical risk in Singapore. METHODS: A de novo Markov model with three health states - stroke with long-term sequelae, no stroke, and death - was developed and simulated using Monte Carlo simulations with 10,000 iterations over a five-year time horizon from the Singapore healthcare system perspective. A 3% annual discount rate for costs and outcomes and monthly cycle lengths were used. By applying the longest available published clinical evidence, simulated patients received either TAVI or surgical aortic valve replacement (SAVR) and were at risk of adverse events (AEs) such as moderate-to-severe paravalvular aortic regurgitation (PAR). RESULTS: When five-year PARTNER 2A data was applied, base-case analyses showed that the incremental cost-effectiveness ratio (ICER) for TAVI compared to SAVR was US$315,760 per quality-adjusted life year (QALY) gained. The high ICER was due to high incremental implantation and procedure costs of TAVI compared to SAVR, and marginal improvement of 0.10 QALYs as simulated mortality of TAVI exceeded SAVR at 3.75 years post-implantation. One-way sensitivity analysis showed that the ICERs were most sensitive to cost of PAR, utility values of SAVR patients, and cost of TAVI and SAVR implants and procedures. When disutilities for AEs were additionally applied, the ICER decreased to US$300,070 per QALY gained. TAVI was dominated by SAVR when the time horizon increased to 20 years. Clinical outcomes projected from one-year PARTNER S3i data further reduced the ICER to US$86,337 per QALY gained for TAVI, assuming early all-cause mortality benefits from TAVI continued to persist. This assumption was undermined when longer term data showed that TAVI's early mortality benefits diminished at five years. LIMITATIONS AND CONCLUSION: TAVI is unlikely to be cost-effective in intermediate surgical-risk patients compared to SAVR in Singapore.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Estenose da Valva Aórtica/cirurgia , Análise Custo-Benefício , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Fatores de Risco , Singapura/epidemiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
18.
Environ Sci Nano ; 9(3): 867-910, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35401985

RESUMO

Quantum dots (QDs) are engineered semiconductor nanocrystals with unique fluorescent, quantum confinement, and quantum yield properties, making them valuable in a range of commercial and consumer imaging, display, and lighting technologies. Production and usage of QDs are increasing, which increases the probability of these nanoparticles entering the environment at various phases of their life cycle. This review discusses the major types and applications of QDs, their potential environmental exposures, fates, and adverse effects on organisms. For most applications, release to the environment is mainly expected to occur during QD synthesis and end-product manufacturing since encapsulation of QDs in these devices prevents release during normal use or landfilling. In natural waters, the fate of QDs is controlled by water chemistry, light intensity, and the physicochemical properties of QDs. Research on the adverse effects of QDs primarily focuses on sublethal endpoints rather than acute toxicity, and the differences in toxicity between pristine and weathered nanoparticles are highlighted. A proposed oxidative stress adverse outcome pathway framework demonstrates the similarities among metallic and carbon-based QDs that induce reactive oxygen species formation leading to DNA damage, reduced growth, and impaired reproduction in several organisms. To accurately evaluate environmental risk, this review identifies critical data gaps in QD exposure and ecological effects, and provides recommendations for future research. Future QD regulation should emphasize exposure and sublethal effects of metal ions released as the nanoparticles weather under environmental conditions. To date, human exposure to QDs from the environment and resulting adverse effects has not been reported.

19.
Nat Nanotechnol ; 17(4): 347-360, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35332293

RESUMO

Achieving sustainable agricultural productivity and global food security are two of the biggest challenges of the new millennium. Addressing these challenges requires innovative technologies that can uplift global food production, while minimizing collateral environmental damage and preserving the resilience of agroecosystems against a rapidly changing climate. Nanomaterials with the ability to encapsulate and deliver pesticidal active ingredients (AIs) in a responsive (for example, controlled, targeted and synchronized) manner offer new opportunities to increase pesticidal efficacy and efficiency when compared with conventional pesticides. Here, we provide a comprehensive analysis of the key properties of nanopesticides in controlling agricultural pests for crop enhancement compared with their non-nanoscale analogues. Our analysis shows that when compared with non-nanoscale pesticides, the overall efficacy of nanopesticides against target organisms is 31.5% higher, including an 18.9% increased efficacy in field trials. Notably, the toxicity of nanopesticides toward non-target organisms is 43.1% lower, highlighting a decrease in collateral damage to the environment. The premature loss of AIs prior to reaching target organisms is reduced by 41.4%, paired with a 22.1% lower leaching potential of AIs in soils. Nanopesticides also render other benefits, including enhanced foliar adhesion, improved crop yield and quality, and a responsive nanoscale delivery platform of AIs to mitigate various pressing biotic and abiotic stresses (for example, heat, drought and salinity). Nonetheless, the uncertainties associated with the adverse effects of some nanopesticides are not well-understood, requiring further investigations. Overall, our findings show that nanopesticides are potentially more efficient, sustainable and resilient with lower adverse environmental impacts than their conventional analogues. These benefits, if harnessed appropriately, can promote higher crop yields and thus contribute towards sustainable agriculture and global food security.


Assuntos
Nanoestruturas , Praguicidas , Agricultura , Segurança Alimentar , Solo
20.
Mar Pollut Bull ; 174: 113254, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34923404

RESUMO

Microplastics are small plastic particles found ubiquitously in marine environments. In this study, a hybridized method was developed for the extraction of microplastics (45-1000 µm) from sediments using sodium bromide solution for density separation. Method development was tested using spiked microplastics as internal standards. The method was then used to extract microplastics from sediments in Narragansett Bay, Rhode Island, USA. Suspect microplastics were analyzed with Raman spectroscopy. Microplastic abundance ranged from 40 particles/100 g sediment to 4.6 million particles/100 g sediment (wet weight). Cellulose acetate fibers were the most abundant microplastic. These results are some of the first data for microplastics in Rhode Island sediments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Baías , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Rhode Island , Poluentes Químicos da Água/análise
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