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1.
J Xenobiot ; 14(2): 812-826, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38921655

RESUMEN

Microplastic contamination in agricultural soil is an emerging problem worldwide as it contaminates the food chain. Therefore, this research investigated the distribution of microplastics (MPs) in agricultural soils without mulch at various depths (0-5, 5-10, and 10-15 cm) across different zones: rural, local market, industrial, coastal, and research areas. The detection of MP types and morphology was conducted using FTIR and fluorescence microscopy, respectively. Eight types of MPs were identified, including high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl fluoride (PVF), polyvinyl alcohol (PVA), and polytetrafluoroethylene (PTFE), with concentrations ranging from 0.6 ± 0.21 to 3.71 ± 2.36 MPs/g of soil. The study found no significant trends in MP concentration, with ranges of 0-2.1 ± 0.38, 0-2.87 ± 0.55, and 0-2.0 ± 0.34 MPs/g of soil at depths of 0-5 cm, 5-10 cm, and 10-15 cm, respectively. The highest MP quantity was recorded at 8.67 in coastal area, while the lowest was 6.44 in the local market area. Various MP shapes, e.g., fiber, film, pellet, fragment, and irregular, were observed across all layers. PCA suggested irrigation and organic manure as potential sources of MPs. The estimated concentrations of MPs possessed low non-carcinogenic and carcinogenic risks to the farming community of Bangladesh.

2.
Nanomaterials (Basel) ; 14(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38921906

RESUMEN

This study presents a comprehensive characterization of microplastics (MPs) and adsorbed/dissolved polycyclic aromatic hydrocarbons (PAHs) in the Arakawa River, the largest river system in Saitama and Tokyo, Japan. The MPs were sampled at various points along the river, revealing an average number density of 2.21 ± 1.48 pieces/m3, with a predominant size range of 0.5-1 mm. Polymer analysis indicated that polyethylene (PE) comprised the highest proportion of MPs (55.9%), followed by polypropylene (PP) (22.4%) and polystyrene (PS) (21.7%). Seasonal fluctuations in MPs concentration were observed, with the highest values in winter and the lowest in summer. An analysis of adsorbed PAHs revealed a median partition coefficient (Kd) value of 3.58 × 104 L/kg for MPs, indicating their affinity for PAHs. Further PAHs analysis revealed that the PAHs with the highest mean values were bicyclic naphthalene, pyrene, and fluoranthene. A comparison with coastal MPs showed differences in PAH composition, with higher proportions of high-ring PAHs observed in coastal samples. The study also investigated the distribution of PAHs in the dissolved and suspended states in the river, finding that similar PAHs were distributed in both states, with the PAHs present in MPs being about 1/10,000 of those in the dissolved and suspended states. The study underscores the importance of the continued monitoring and management of MPs and associated pollutants in river ecosystems.

3.
Aging Clin Exp Res ; 36(1): 56, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441718

RESUMEN

BACKGROUND AND AIMS: Acute myocardial infarction (AMI) is one of the most prevalent illnesses endangering the elderly's health. The predictive nutritional index (PNI) has been shown in several studies to be a good predictor of nutritional prognosis. In this study, we explored the correlation between PNI during hospitalization and the outcome of elderly AMI patients. METHODS: Elderly AMI patients in the Cardiac Intensive Care Unit of Huadong Hospital from September 2017 to April 2020 were recruited for analysis. The clinical and laboratory examination data of subjects were retrieved. All enrolled patients were monitored following discharge. The primary clinical endpoints encompass major adverse cardiovascular events (MACEs) and Composite endpoint (MACEs and all-cause mortality). Survival analyses were conducted via the Kaplan-Meier and the log-rank analyses, and the Cox, proportional hazards model, was employed for hazard rate (HR) calculation. RESULTS: 307 subjects were recruited for analysis. The optimal PNI threshold is 40.923. Based on the Kaplan-Meier analysis, the elevated PNI group experienced better prognosis (P < 0.001). Cox analysis demonstrated that the PNI group was a stand-alone predictor for elderly AMI patient prognosis (HR = 1.674, 95% CI 1.076-2.604, P = 0.022). Subgroup analysis showed that the HR of the PNI group was the highest in the ST-segment elevation myocardial infarction (STEMI) subgroup (HR = 3.345, 95% CI 1.889-5.923, P = 0.05), but no discernible difference was observed in the non-ST-segment elevation myocardial infarction (NSTEMI) subgroup. CONCLUSION: Based on our analyses, the PNI during hospitalization can accurately predict the prognosis of elderly STEMI patients but not that of elderly NSTEMI patients.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Infarto del Miocardio con Elevación del ST , Anciano , Humanos , Evaluación Nutricional , Pronóstico , Estudios Retrospectivos , Infarto del Miocardio/diagnóstico , Hospitalización
4.
J Med Imaging (Bellingham) ; 11(1): 014008, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38379775

RESUMEN

Purpose: In recent years, the continuous advancement of convolutional neural networks (CNNs) has led to the widespread integration of deep neural networks as a mainstream approach in clinical diagnostic support. Particularly, the utilization of CNN-based medical image segmentation has delivered favorable outcomes for aiding clinical diagnosis. Within this realm, network architectures based on the U-shaped structure and incorporating skip connections, along with their diverse derivatives, have gained extensive utilization across various medical image segmentation tasks. Nonetheless, two primary challenges persist. First, certain organs or tissues present considerable complexity, substantial morphological variations, and size discrepancies, posing significant challenges for achieving highly accurate segmentation. Second, the predominant focus of current deep neural networks on single-resolution feature extraction limits the effective extraction of feature information from complex medical images, thereby contributing to information loss via continuous pooling operations and contextual information interaction constraints within the U-shaped structure. Approach: We proposed a five-layer pyramid segmentation network (PS5-Net), a multiscale segmentation network with diverse resolutions that is founded on the U-Net architecture. Initially, this network effectively leverages the distinct features of images at varying resolutions across different dimensions, departing from prior single-resolution feature extraction methods to adapt to intricate and variable segmentation scenarios. Subsequently, to comprehensively integrate feature information from diverse resolutions, a kernel selection module is proposed to assign weights to features across different dimensions, enhancing the fusion of feature information from various resolutions. Within the feature extraction network denoted as PS-UNet, we preserve the classical structure of the traditional U-Net while enhancing it through the incorporation of dilated convolutions. Results: PS5-Net attains a Dice score of 0.9613 for liver segmentation on the CHLISC dataset and 0.8587 on the ISIC2018 dataset for skin lesion segmentation. Comparative analysis with diverse medical image segmentation methodologies in recent years reveals that PS5-Net has achieved the highest scores and substantial advancements. Conclusions: PS5-Net effectively harnesses the rich semantic information available at different resolutions, facilitating a comprehensive and nuanced understanding of the input medical images. By capitalizing on global contextual connections, the network adeptly captures the intricate interplay of features and dependencies across the entire image, resulting in more accurate and robust segmentation outcomes. The experimental validation of PS5-Net underscores its superior performance in medical image segmentation tasks, offering promising prospects for enhancing diagnostic and analytical processes within clinical settings. These results highlight the potential of PS5-Net to significantly contribute to the advancement of medical imaging technologies and ultimately improve patient care through more precise and reliable image analysis.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38356213

RESUMEN

RGB-D salient object detection (SOD) has gained tremendous attention in recent years. In particular, transformer has been employed and shown great potential. However, existing transformer models usually overlook the vital edge information, which is a major issue restricting the further improvement of SOD accuracy. To this end, we propose a novel edge-aware RGB-D SOD transformer, called, which explicitly models the edge information in a dual-band decomposition framework. Specifically, we employ two parallel decoder networks to learn the high-frequency edge and low-frequency body features from the low-and high-level features extracted from a two-steam multimodal backbone network, respectively. Next, we propose a cross-attention complementarity exploration module to enrich the edge/body features by exploiting the multimodal complementarity information. The refined features are then fed into our proposed color-hint guided fusion module for enhancing the depth feature and fusing the multimodal features. Finally, the resulting features are fused using our deeply supervised progressive fusion module, which progressively integrates edge and body features for predicting saliency maps. Our model explicitly considers the edge information for accurate RGB-D SOD, overcoming the limitations of existing methods and effectively improving the performance. Extensive experiments on benchmark datasets demonstrate that is an effective RGB-D SOD framework that outperforms the current state-of-the-art models, both quantitatively and qualitatively. A further extension to RGB-T SOD demonstrates the promising potential of our model in various kinds of multimodal SOD tasks.

6.
Toxics ; 11(11)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37999573

RESUMEN

Respiratory diseases have been proven to be directly related to air pollutants. Xuanwei, located in South China, has been known to have the highest mortality rate for lung cancer in China because of the air pollutants emitted through local coal combustion. However, the mechanism of lung cancer induced by air pollutants is not clear. Based on the fact that a large number of iron-bearing mineral particles was found in Xuanwei coal combustion particles, the iron-containing particles were hypothesized to play important roles in the pathogenesis of the high incidence rate of lung cancer in this area. In this study, raw coal samples were collected from a coal mine in the Xuanwei area. Size-resolved particles emitted from the raw coal samples were collected using an Anderson high-volume sampler. Mineralogical characterization and an assessment of the oxidative potential of the iron-containing particles were conducted using cutting-edge technologies, and the biological activity of the particles were evaluated via DTT assay. Our data showed that the iron-containing minerals accounted for more than 10% of the measured particles emitted from Xuanwei coal combustion samples. The content analysis of ·OH generated from Xuanwei coal combustion particles showed that ·OH content was dependent on the size of particles in the surrogated lung fluid. The concentration of ·OH increased as the particle size decreased. The DTT assay data further demonstrated that when the mass concentration of dissolved irons increased, the oxidation potential of the particles increased. The highest proportion of divalent iron in the total dissolved iron was found in the submicron particles in low pH solution(pH = 1), which indicated that the oxidative potential induced by submicron particles was stronger than that induced by coarse particles and fine particles. Armed with the above data, the toxicological mechanism of the iron-containing mineral particles can be investigated further.

7.
Innovation (Camb) ; 4(6): 100505, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37744177

RESUMEN

The renowned mechanical performance of biological ceramics can be attributed to their hierarchical structures, wherein structural features at the nanoscale play a crucial role. However, nanoscale features, such as nanogradients, have rarely been incorporated in biomimetic ceramics because of the challenges in simultaneously controlling the material structure at multiple length scales. Here, we report the fabrication of artificial nacre with graphene oxide nanogradients in its aragonite platelets through a matrix-directed mineralization method. The gradients are formed via the spontaneous accumulation of graphene oxide nanosheets on the surface of the platelets during the mineralization process, which then induces a lateral residual stress field in the platelets. Nanoindentation tests and mercury intrusion porosimetry demonstrate that the material's energy dissipation is enhanced both intrinsically and extrinsically through the compressive stress near the platelet surface. The energy dissipation density reaches 0.159 ± 0.007 nJ/µm3, and the toughness amplification is superior to that of the most advanced ceramics. Numerical simulations also agree with the finding that the stress field notably contributes to the overall energy dissipation. This work demonstrates that the energy dissipation of biomimetic ceramics can be further increased by integrating design principles spanning multiple scales. This strategy can be readily extended to the combinations of other structural models for the design and fabrication of structural ceramics with customized and optimized performance.

8.
J Am Chem Soc ; 145(35): 19283-19292, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37585603

RESUMEN

Precise tailoring of the aggregation state of covalent organic frameworks (COFs) to form a hierarchical porous structure is critical to their performance and applications. Here, we report a one-pot and one-step strategy of using dynamic combinatorial chemistry to construct imine-based hollow COFs containing meso- and macropores. It relies on a direct copolymerization of three or more monomers in the presence of two monofunctional competitors. The resulting particle products possess high crystallinity and hierarchical pores, including micropores around 0.93 nm, mesopores widely distributed in the range of 3.1-32 nm, and macropores at about 500 nm, while the specific surface area could be up to 748 m2·g-1, with non-micropores accounting for 60% of the specific surface area. The particles demonstrate unique advantages in the application as nanocarriers for in situ loading of Pd catalysts at 93.8% loading efficiency in the copolymerization of ethylene and carbon monoxide. The growth and assembly of the copolymer could thus be regulated to form flower-shaped particles, efficiently suppressing the fouling of the reactor. The copolymer's weight-average molecular weight and the melting temperature are also highly improved. Our method provides a facile way of fabricating COFs with hierarchical pores for advanced applications in catalysis.

9.
Environ Geochem Health ; 45(11): 7829-7839, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37486413

RESUMEN

Environmental persistent free radicals (EPFRs) are receiving growing concerns owing to their potentially adverse impacts on human health. Road dust is one important source of air pollution in most cities and may pose significant health risks. Characteristics of EPFRs in urban road dusts and its formation mechanism(s) are still rarely studied. Here, we evaluated occurrence and size distributions of EPFRs in road dusts from different functional areas of an urban city, and assessed relationship between EPFRs and some transition metals. Strong electron paramagnetic resonance signals of 6.01 × 1016 - 1.3 × 1019 spins/g with the mean g value of 2.0029 ± 0.0019 were observed, indicating that EPFRs consisted of a mixture of C-centered radicals, and C-centered radicals with an adjacent oxygen atom in the urban road dust. Much more EPFRs enriched in finer dust particles. EPFRs significantly correlated with the total Fe, but not water-soluble Fe, suggesting different impacts of water-soluble and insoluble metals in the formation of EFPRs. Health risk assessment results indicated high risk potentials via the ingestion and dermal exposure to EPFRs in road dusts. Future studies are calling to look into formation mechanisms of EPFRs in urban road dusts and to quantitatively evaluate its potential risks on human health.


Asunto(s)
Contaminación del Aire , Elementos de Transición , Humanos , Polvo/análisis , Radicales Libres , Ciudades , Monitoreo del Ambiente
10.
ACS Nano ; 17(15): 14686-14694, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37459214

RESUMEN

Natural plant fibers such as cotton have favorable performance in water and moisture management; however, they suffer from inferior processing ability due to limited diameter and length, as well as natural defects. Although commercially available regenerated cellulose fibers such as lyocell fibers can have tunable structures, they rely on the complete dissolution of cellulose molecules, including the highly crystalline parts, leading to inferior mechanical properties. Through a specially designed coaxial wet-spinning process, we prepare a type of hollow fiber using only cellulose nanofibrils (CNFs) as building blocks. It mimics cotton fibers with a lumen structure but with a tunable diameter and a long length. Moreover, such hollow fibers have superior mechanical properties with a Young's modulus of 24.7 GPa and tensile strength of 341 MPa, surpassing lyocell fibers and most wet-spun CNF-based fibers. Importantly, they have 10 times higher wicking ability, wetting rate, drying rate, and maximum wetting ratio compared to lyocell fibers. Together with a superior long-term performance after 500 rounds of wetting-drying tests, such CNF-based hollow fibers are sustainable choices for advanced textile applications. And this study provides a greater understanding of nanoscale building blocks and their assembled macromaterials, which may help to reveal the magic hierarchical design of natural materials, in this case, plant fibers.

11.
Environ Pollut ; 334: 122134, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37414123

RESUMEN

Mineral particles in air could provide atmospheric chemical reaction interface for gaseous substances and participate in atmospheric chemical reaction process, and affecting the status and levels of gaseous pollutants in air. However, differences of the heterogenous reaction on the surface minerals particles are not very clear. Considering main mineral composition of ambient particles was from dust emission, therefore, typical clay minerals (chlorite, illite) and desert particles (Taklimakan Desert) were selected to analysize chemical reaction of NO2, one of major gaseous pollutants, on mineral particles by using of In-situ DRIFTS (diffuse reflectance infrared Fourier transform spectroscopy) under different condition. And In situ near-ambient pressure X-ray photoelectron spectroscopy (In situ NAP-XPS) was employed to investigate iron (one of the major metals) species variation on the surface of mineral dust particles during the heterogeneous reactions. Our data show that humidity controlled by deuterium oxide (D2O) has a greater effect on chemical reactions compared to light and temperature. Under dry conditions, the amount of heterogeneous reaction products of NO2 on the particles shows Xiaotang dust > chlorite > illite > Tazhong dust regardless of dark or light conditions. In contrast, under humidity conditions, the order of nitrate product quantity under moderate conditions was chlorite > illite > Xiaotang dust > Tazhong dust. In situ NAP-XPS results demonstrate that specie variation of the Fe could promote the heterogenous reactions. These data could provide useful information for understanding the formation mechanism of nitrate aerosols and removal of nitrogen oxides in the atmosphere.


Asunto(s)
Polvo , Contaminantes Ambientales , Polvo/análisis , Arcilla , Dióxido de Nitrógeno/química , Nitratos , Minerales/química , Gases , Aerosoles/química
12.
Chemistry ; 29(54): e202300913, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37341127

RESUMEN

The loading of homogeneous catalysts with support can dramatically improve their performance in olefin polymerization. However, the challenge lies in the development of supported catalysts with well-defined pore structures and good compatibility to achieve high catalytic activity and product performance. Herein, we report the use of an emergent class of porous material-covalent organic framework material (COF) as a carrier to support metallocene catalyst-Cp2 ZrCl2 for ethylene polymerization. The COF-supported catalyst demonstrates a higher catalytic activity of 31.1×106  g mol-1 h-1 at 140 °C, compared with 11.2×106  g mol-1 h-1 for the homogenous one. The resulting polyethylene (PE) products possess higher weight-average molecular weight (Mw ) and narrower molecular weight distribution (Ð) after COF supporting, that is, Mw increases from 160 to 308 kDa and Ð drops from 3.3 to 2.2. The melting point (Tm ) is also increased by up to 5.2 °C. Moreover, the PE product possesses a characteristic filamentous microstructure and demonstrates an increased tensile strength from 19.0 to 30.7 MPa and elongation at break from 350 to 1400 % after catalyst loading. We believe that the use of COF carriers will facilitate the future development of supported catalysts for highly efficient olefin polymerization and high-performance polyolefins.

13.
Angew Chem Int Ed Engl ; 62(40): e202305644, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37325872

RESUMEN

Chemical upcycling of polyethylene (PE) can convert plastic waste into valuable resources. However, engineering a catalyst that allows PE decomposition at low temperatures with high activity remains a significant challenge. Herein, we anchored 0.2 wt.% platinum (Pt) on defective two-dimensional tungsten trioxide (2D WO3 ) nanosheets and achieved hydrocracking of high-density polyethylene (HDPE) waste at 200-250 °C with a liquid fuel (C5-18 ) formation rate up to 1456 gproducts ⋅ gmetal species -1 ⋅ h-1 . The reaction pathway over the bifunctional 2D Pt/WO3 is elucidated by quasi-operando transmission infrared spectroscopy, where (I) well-dispersed Pt immobilized on 2D WO3 nanosheets trigger the dissociation of hydrogen; (II) adsorption of PE and activation of C-C cleavage on WO3 are through the formation of C=O/C=C intermediates; (III) intermediates are converted to alkane products by the dissociated H. Our study directly illustrates the synergistic role of bifunctional Pt/WO3 catalyst in the hydrocracking of HDPE, paving the way for the development of high-performance catalysts with optimized chemical and morphological properties.

14.
Environ Anal Health Toxicol ; 38(1): e2023005-0, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37100400

RESUMEN

Garri from cassava is one of the most consumed foods in West Africa, hence this research was conducted to examine microplastics (MPs) and potentially toxic elements (PTEs) in garri from Nigeria (West Africa) and Japan. This is the first investigation on MPs in garri samples that has been reported in the literature. The study analyzed both packaged and unpackaged vended garri samples using microscopic/spectroscopic and X-ray fluorescence techniques for MPs and PTEs respectively. Microplastic particles in the garri samples ranged from (or were between) 2.00±2.00 - 175.00±25.16 particles/50 with > 90 % as fragments and consisted of polyacrylamide, polyethylene terepthalate, polyvinyl alcohol, high density polyethylene, polyvinyl chloride acrylonitrile, polyethylene chlorinated, polypropylene with silicate mix, polychloroprene and polyethylene chlorosulphonated. The mean concentration of PTEs raged from ND to 0.07 mg/g for Cr and Mn, 0.73 to 5.63 mg/g for Fe, ND to 0.57mg/g for Co, 0.23 to 1.21 mg/g for Ni, 0.15 to 1.53 mg/g for Cu, and 0.12 to 0.63 mg/g for Zn. However, their daily intake was low for both adult and children as with the MPs. The sources of MPs and PTEs were mainly from the garri production processes, atmospheric dusts and during packaging. The non-carcinogenic risk for all samples was low for MPs while in openly vended garri, Ni and Cr in all sample poses carcinogenic risks. There is a need to improve indigenous garri processing techniques to minimize contamination. This research emphasizes the critical necessity to understand the consequences of MPs on human health.

15.
Environ Geochem Health ; 45(6): 2869-2889, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36088450

RESUMEN

The highest incidence and mortality rate of lung cancer in rural area of Fuyuan has been a research hotspot, and the pathogenesis is still unclear. Therefore, atmospheric particulate matters (APMs) samples were collected between 18 February and 01 March 2017, exploring water-soluble potentially toxic metals (WSPTMs) and water-soluble inorganic ionic species (WSIIs) levels, size distribution, sources, acidity and alkalinity, and potential carcinogenic and non-carcinogenic risks, hoping to provide scientific basic data to solve this problem. In our study, the average ratio of nitrate ion (NO3-)/sulfate ion (SO42-) within PM1.1, PM1.1-2.0, PM2.0-3.3, PM3.3-7.0, and PM>7.0 were 0.22, 0.18, 0.15, 0.34 and 0.36, respectively, that revealed that combustion sources contributed to PM were more significant. The anions in equilibrium (ANE) / cations in equilibrium (CAE) < 1 for all samples within PM1.1, PM2.0-3.3, PM3.3-7.0 indicate that the APMs were alkaline, but PM1.1-2.0 particulate matter shows weak acidity. SO42- prefers to combine with NH4+ to form (NH4)2SO4, which hinders the formation of NH4NO3, the remaining SO42- and NO3- to neutralize the K+, KNO3 was formed at all particulate, however, K2SO4 can only be formed in PM<3.3. Arsenic (As) and Selenium (Se) were identified as the most enriched WSPTMs in all PM sizes, predominantly from anthropogenic emissions, were suggested that coal combustion is a significant source of PM-bound WSPTMs. Total WSPTMs exhibited high total carcinogenic risks (TCR) values (9.98 × 10-6, 1.06 × 10-5, and 1.19 × 10-5 for girls, boys and adults, respectively) in the smaller particles (< 1.1 µm). Se was considered as the major contributor (63.60%) to carcinogenic risk (CR) in PM2.0 and had an inverse relationship with PM size that should be of prime concern.


Asunto(s)
Contaminantes Atmosféricos , Neoplasias Pulmonares , Adulto , Humanos , Material Particulado/toxicidad , Material Particulado/análisis , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Tamaño de la Partícula , Incidencia , Agua , Medición de Riesgo , China/epidemiología , Sulfatos/análisis , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/epidemiología , Monitoreo del Ambiente , Estaciones del Año
16.
Environ Sci Pollut Res Int ; 30(2): 4323-4345, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35971052

RESUMEN

Due to the COVID-19 pandemic, Bangladesh government took the measure like partial lockdown (PL) and complete lockdown (CL) to curb the spread. These measures gave a chance for environmental restoration. In this study, street dust samples were collected during PL and CL from four main urban land use categories in Dhaka city, such as industrial area (IA), commercial area (CA), public facilities area (PFA), and residential area (RA). Ten potentially toxic elements (Cr, Mn, Zn, Fe, Pb, Cu, Co, Ni, As, and Cd) in fine street dust particles (diameter < 20 µm) were determined following aqua-regia digestion and measured by inductively coupled plasma mass spectrometry (ICP-MS) to evaluate distribution, pollution sources, and potential risks to ecological systems and human health. Results showed that during PL, the concentrations of toxic elements in the dust were higher than that of CL. Cd and Fe were lowest and highest in concentration with 1.56 to 41,970 µg/g and 0.82 to 39,330 µg/g in partial and complete lockdown period respectively. All toxic elements were detected at high levels above background values where Fe with the highest and Cd with lowest concentrations, respectively. By land use, the levels of toxic elements pollution followed IA > PFA > RA > CA. Correlation analysis (CA), principal component analysis (PCA), and hierarchal cluster analysis (HCA) revealed that the sources of these analyzed toxic elements were mainly from anthropogenic which are related to industrial and vehicular or traffic emissions. Enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI) also suggested that the dust was more polluted during PL. Exposure of toxic elements to human was mainly via skin contact followed by ingestion and inhalation. Hazard quotient (HQ) values were < 1 except for Mn through dermal contact at all sites during partial and complete lockdown, similar to hazard index (HI), while Cr further showed high non-carcinogenic risks to children. Generally, children HI values were about 5-6 times higher than those of adults, suggesting a greater vulnerability of children to the health concerns caused by toxic elements in street dust. Carcinogenic risk (CR) values via ingestion pathway indicated all elements (except Pb) had significant health effect, while CR value by inhalation results showed no significant health effect. Cumulative carcinogenic risk (CCR) value had significant health effect except Pb in all land use categories. CCR values decreased during CL and reached at acceptable limit for most of the cases. This research provides a message to the local governments and environmental authorities to have a complete assessment of toxic elements in the street dust of Dhaka megacity in order to assuring public health safety and ecological sustainability.


Asunto(s)
COVID-19 , Metales Pesados , Adulto , Niño , Humanos , Polvo/análisis , Bangladesh , Cadmio/análisis , Plomo/análisis , Pandemias , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Control de Enfermedades Transmisibles , Ciudades , Medición de Riesgo/métodos , Carcinógenos/análisis , China
17.
J Hazard Mater ; 446: 130600, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36584646

RESUMEN

Following the discovery of plastics in the human placenta, this study evaluated the toxicity of ten different nanoplastics (NPs) in the human placenta. Since the placenta performs metabolic and excretion functions by the enzymatic system, the NPs were docked on these human enzymes including soluble epoxide hydrolase, uracil phosphoribosyltransferase, beta 1,3-glucuronyltransferase I, sulfotransferase, N-acetyltransferase 2, and cytochrome P450 1A1at their active sites with toxicity (binding affinity) determined and compared to control compounds. Density functional theory analysis were conducted on the NPs to identify their global reactivity descriptors and Artificial Neural Networks to predict toxicity based on reactivity descriptors. Polycarbonate (PC), polyethylene terephthalate (PET) and polystyrene (PS) showed the highest toxicity to all enzymes and thus the most toxic polymers due to the presence of an electron-withdrawing group in their aromatic rings, which demonstrated an improved recognition of the enzyme active site by pi- and alkyl interactions. A 210-6 fractional factorial design approach was used in conjunction with a fixed effects model to assess the primary and secondary effects of NPs in a composite system on binding affinity to the placental enzymes. The simulation results suggest that NPs mixture may pose significant risks to the placenta through inhibition of its key enzymes.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Humanos , Embarazo , Femenino , Placenta , Microplásticos , Nanopartículas/química , Contaminantes Químicos del Agua/química , Plásticos , Poliestirenos/química
18.
Front Pediatr ; 10: 1019314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36389387

RESUMEN

Background: This study aimed to observe the prognosis of patients with moderate-to-severe pediatric acute respiratory distress syndrome (PARDS) admitted to the Pediatric Intensive Care Unit (PICU) as a function of underlying conditions and available treatment strategies, and to investigate the risk factors for death and the outcomes of different clinical subphenotypes. Methods: Patients were divided into non-survivors and survivors according to the prognosis 28 days after the diagnosis. The risk factors for death and the predictive value of relevant factors for mortality were analyzed. Latent class analysis was used to identify different clinical subphenotypes. Results: A total of 213 patients with moderate-to-severe PARDS were enrolled, of which 98 (46.0%) died. Higher PELOD2 scores (OR = 1.082, 95% CI 1.004-1.166, p < 0.05), greater organ failure (OR = 1.617, 95% CI 1.130-2.313, p < 0.05), sepsis (OR = 4.234, 95% CI 1.773-10.111, p < 0.05), any comorbidity (OR = 3.437, 95% CI 1.489-7.936, p < 0.05), and higher infiltration area grade (IAG) (OR = 1.980, 95% CI 1.028-3.813, p < 0.05) were associated with higher mortality. The combination of these five indicators had the largest area under the curve (sensitivity 89.79%, specificity 94.78%). Patients were classified into higher-risk and lower-risk phenotype group according to the latent class analysis. Compared to the lower-risk phenotype, more patients with higher-risk phenotype suffered from sepsis (24.40% vs. 12.20%, p < 0.05), inherited metabolic diseases (45.80% vs. 25.60%, p < 0.05), positive respiratory pathogens (48.10% vs. 26.80%, p < 0.05), and higher IAG (p < 0.05); they also had significantly higher PIM3 and PELOD2 scores (p < 0.05), with an extremely high mortality rate (61.1% vs. 22.0%, p < 0.05). Conclusions: Moderate-to-severe PARDS has high morbidity and mortality in PICU; a higher PELOD2 score, greater organ failure, sepsis, any comorbidity, and higher IAG were risk factors for death, and the combination of these five indicators had the greatest value in predicting prognosis. More patients with sepsis, positive respiratory pathogens, higher PIM3 and PELOD2 scores, and higher IAG were in higher-risk phenotype group, which had worse outcomes. Clear classification facilitates targeted treatment and prognosis determination.

19.
Environ Technol ; : 1-20, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36269120

RESUMEN

Microplastics (MPs) and phenolics are pollutants found ubiquitously in freshwater systems. MPs oftentimes serve as a vector for pollutants across ecosystems and are now being explored as alternative adsorbents for pollutant removal. This strategy would reflect the 'reuse' of an existing waste stream into a potentially useful product while at the same time helping to minimize plastic waste in the marine environment. In this study, the adsorption of phenol onto pristine (Pr-PET), modified (Mod-PET), and aged (Ag-PET) Polyethylene Terephthalate (PET) microplastics was examined experimentally and theoretically. Kinetics, isotherms, and thermodynamics models were used to investigate the adsorption process while Grand Canonical Monte Carlo (GCMC) and molecular dynamics (MD) simulations were employed to investigate molecular level alterations. The result showed that the Ag-PET MPs had the best removal efficiency due larger surface area and the adsorption occurred in a pseudo-second-order manner, showing that the rate of phenol adsorption is directly proportional to the number of surface-active sites on the surface of PET MPs while the intraparticle diffusion defined rate-limiting step. However, the maximum monolayer adsorption capacity followed Mod-PET (38.02 mg/g) > Ag-PET (8.08 mg/g) > Pr-PET (6.84 mg/g). The adsorption process proceeded spontaneously and thermodynamically favourable. GCMC-MD simulations revealed that PET MPs are capable of successfully adsorbing the phenol molecule through Van der Waals and electrostatic interactions and can be adopted as novel adsorbents for phenol removal in aqueous solutions.

20.
Artículo en Inglés | MEDLINE | ID: mdl-36078598

RESUMEN

House dust mite (HDM) is a globally ubiquitous domestic cause of allergic diseases. There is a pressing demand to discover efficient, harmless, and eco-friendly natural extracts to inhibit HDM allergens that are more likely to trigger allergies and challenging to be prevented entirely. This study, therefore, is aimed at assessing the inhibition of the allergenicity of major HDM allergen Der f 2 by todomatsu oil extracted from residues of Abies Sachalinensis. The inhibition was investigated experimentally (using enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)) and in silico using molecular docking. The results showed that todomatsu oil inhibits the allergenicity of Der f 2 by reducing its amount instead of the IgG binding capacity of a single protein. Moreover, the compounds in todomatsu oil bind to Der f 2 via alkyl hydrophobic interactions. Notably, most compounds interact with the hydrophobic amino acids of Der f 2, and seven substances interact with CYS27. Contrarily, the principal compounds fail to attach to the amino acids forming the IgG epitope in Der f 2. Interestingly, chemical components with the lowest relative percentages in todomatsu oil show high-affinity values on Der f 2, especially ß-maaliene (-8.0 kcal/mol). In conclusion, todomatsu oil has been proven in vitro as a potential effective public health strategy to inhibit the allergenicity of Der f 2.


Asunto(s)
Abies , Alérgenos , Antígenos Dermatofagoides , Hipersensibilidad , Aceites de Plantas , Pyroglyphidae , Abies/química , Alérgenos/farmacología , Aminoácidos , Animales , Antígenos Dermatofagoides/metabolismo , Antígenos Dermatofagoides/farmacología , Proteínas de Artrópodos , Polvo/análisis , Bosques , Humanos , Inmunoglobulina G , Simulación del Acoplamiento Molecular , Aceites de Plantas/química , Aceites de Plantas/metabolismo , Aceites de Plantas/farmacología , Pyroglyphidae/química
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