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1.
ACS Nano ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635335

RESUMO

Expounding bioaccumulation pathways of nanoplastics in organisms is a prerequisite for assessing their ecological risks in the context of global plastic pollution. Invertebrate uptake preference toward nanoplastics is a key initial step of nanoplastic food chain transport that controls their global biosafety, while the biological regulatory mechanism remains unclear. Here, we reveal a preferential uptake mechanism involving active avoidance of nanoplastics by Caenorhabditis elegans and demonstrate the relationship between the uptake preference and nanoplastic characteristics. Nanoplastics with 100 nm in size or positive surface charges induce stronger avoidance due to higher toxicity, causing lower accumulation in nematodes, compared to the 500 nm-sized or negatively charged nanoplastics, respectively. Further evidence showed that nematodes did not actively ingest any types of nanoplastics, while different nanoplastics induced defense responses in a toxicity-dependent manner and distinctly stimulated the avoidance behavior of nematodes (ranged from 15.8 to 68.7%). Transcriptomics and validations using mutants confirmed that the insulin/IGF signaling (IIS) pathway is essential for the selective avoidance of nanoplastics. Specifically, the activation of DAF-16 promoted the IIS pathway-mediated defense against nanoplastics and stimulated the avoidance behavior, increasing the survival chances of nematodes. Considering the genetical universality of this defense response among invertebrates, such an uptake preference toward certain nanoplastics could lead to cascaded risks in the ecosystem.

2.
Talanta ; 275: 126085, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615458

RESUMO

Timely and rapid detection of antibiotic residues in the environment is conducive to safeguarding human health and promoting an ecological virtuous cycle. A foldable paper-based photoelectrochemical (PEC) sensor was successfully developed for the detection of ampicillin (AMP) based on glutathione/zirconium dioxide hollow nanorods/aptamer (GSH@ZrO2 HS@apt) modified cellulose paper as a reactive zone with laser direct-writing lead sulfide/cadmium sulfide/graphene (PbS/CdS/LIG) as photoelectrode and cobalt hydroxide (CoOOH) as a photoresist material. Initially, AMP was introduced into the paper-based reaction zone as a biogate aptamer, which specifically recognized the target and then left the ZrO2 HS surface, releasing glutathione (GSH) encapsulated inside. Subsequently, the introduction of GSH into the reaction region and etching of CoOOH nanosheets to expose the PbS/CdS/LIG photosensitive material increased photocurrent. Under optimal conditions, the paper-based PEC biosensor showed a linear response to AMP in the range of 5.0 - 2 × 104 pM with a detection limit of 1.36 pM (S/N = 3). In addition, the constructed PEC sensing platform has excellent selectivity, high stability and favorable reproducibility, and can be used to assess AMP residue levels in various real water samples (milk, tap water, river water), indicating its promising application in environmental antibiotic detection.

3.
Am J Ophthalmol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615831

RESUMO

PURPOSE: To evaluate changes in retinal microvascular density and choroidal vascularity in patients with retinoblastoma (RB) after intra-arterial chemotherapy (IAC). DESIGN: Retrospective clinical cohort study. METHODS: This study included 12 unilateral RB eyes treated with IAC (RB tumour), 12 contralateral normal eyes (RB fellow), and 12 healthy controls. The macular retinal thickness and retinal microvascular structure, including foveal avascular zone (FAZ) area, the macular and peripapillary superficial vessel density (SVD) and deep vessel density (DVD), were measured by optical coherence tomography angiography (OCTA). The choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA) and Choroidal Vascularity Index (CVI), were measured by spectral-domain optical coherence tomography (SD-OCT). A comparison among the three groups was conducted, while the correlations among the parameters were analyzed. RESULTS: Between the three cohorts, the foveal retinal thickness, the SVD, DVD, ChT, TCA, LA, SA and CVI were significantly lower in RB tumour compared to RB fellow and the control eyes (all P<0.01). There were no significant differences in the parameters between the contralateral and control eyes. The correlation analyses indicated a significant negative correlation between the total melphalan dose and foveal and parafoveal DVD, ChT, and LA. CONCLUSIONS: The retinal microvascular density and choroidal vascularity were lower in unilateral RB treated with IAC, and seemed to be related to the total melphalan dose. Moreover there were no measurable changes in the contralateral eyes.

4.
Br J Ophthalmol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499321

RESUMO

AIMS: To describe the clinical features, multimodal imaging, treatments and natural course of acute spontaneous vortex vein occlusion. METHODS: Clinical data were collected on nine patients with acute vortex vein occlusion. The symptoms and signs, multimodal imaging, treatments and follow-up results were summarised. RESULTS: Six patients (66.7%) were men and three (33.3%) were women. The mean age was 47.8±15.4 years. Patients were initially misdiagnosed as having choroidal tumour (66.7%), scleritis (22.2%) and peripheral exudative haemorrhagic chorioretinopathy (11.1%). The related clinical characteristics included choroidal pseudo-tumour (100%), anterior segment injection (88.9%), acute ocular pain (77.8%), transient blurred vision (66.7%) and subsequent scleral icterus (66.7%). Six patients (66.7%) experienced a definite Valsalva manoeuvre prior to the onset. In acute phase, ultrasonography showed a low-to-medium reflective lesion without inside blood flow signal (mean thickness, 2.7±0.6 mm). Swept-source optical coherence tomography angiography (SS-OCTA) demonstrated the dilated vortex veins and ampulla with suprachoroidal haemorrhage and exudation. Indocyanine green angiography (ICGA) demonstrated choroidal circulation abnormalities in the affected quadrant. MRI showed a well-defined mass with enhancement. The main treatment was medical observation (44.5%). The choroidal pseudo-tumour spontaneously resolved with a mean course of 4.1±1.9 weeks. CONCLUSIONS: Acute vortex vein occlusion is a rare condition and initial misdiagnosis is not uncommon. It is mainly identified as an evanescent choroidal pseudo-tumour with acute pain, red eye and blurred vision. Widefield ICGA and SS-OCTA can offer valuable diagnostic clues. Medical observation may be a treatment option.

5.
Water Res ; 251: 121174, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38277821

RESUMO

Despite the crucial role of photodegradation in the environmental transformation of organic pollutants, the photodegradation process of organic pollutants irreversibly absorbed on biochar colloids (BCCs) remains poorly understood. This study investigated the photodegradation processes and mechanisms of 2,4,4'-trichlorobiphenyl (PCB28) adsorbed on BCCs released from bulk biochars derived from bamboo chips at pyrolysis temperatures of 300, 500, and 700 °C. Results show that BCCs-adsorbed PCB28 could be degraded under simulated solar illumination (95-105 mW·cm-2) but at decreased photodegradation rates compared to the dissolved PCB28. The inhibition effect of BCCs on the PCB28 photodegradation increased with increasing pyrolysis temperature. After adsorptive binding to BCCs, the half-life of PCB28 (0.1 mg/L) was prolonged from 2.65 h for the dissolved PCB28 alone in deionized water to 7.48, 40.67, and 81.82 h in the presence of BCC300, BCC500, and BCC700 (5.0 mg/L), respectively. Mechanistically, the photodegradation of adsorbed pollutants was regulated by the photogenerated free radicals and surface functional groups of the low-temperature BCCs, as well as the defects and direct electron transfer capabilities of the high-temperature BCCs; PCB28 adsorbed on the low-temperature BCCs accepted electrons from persistent free radicals under light illumination, which led to PCB28 dechlorination, followed by ring-opening oxidation through hydroxyl radical attack, ultimately resulting in progressive mineralization; singlet oxygen caused preferential ring opening of adsorbed PCB28 on the high-temperature BCCs, preceding dechlorination. The photodegradation of BCCs-adsorbed PCB28 remained significant though more or less being inhibited under the effects of water pH, ionic strength, dissolved organic matters (humic acid and fulvic acid), and in natural water samples. These findings contribute to a better understanding of the structural properties of BCCs that impact phototransformation processes of adsorbed pollutants and facilitate an accurate assessment of the environmental risk associated with biochar application.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Temperatura , Pirólise , Fotólise , Carvão Vegetal/química , Coloides , Água , Radicais Livres
6.
J Mater Chem B ; 12(4): 984-990, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38193153

RESUMO

A photocurrent-polarity-switching photoelectrochemical (PEC) biosensor was developed for the ultrasensitive detection of tobramycin (TOB) through bipedal DNA walker amplification with hemin-induced photocurrent-polarity-switching using a laser-induced zinc oxide/graphene (ZnO/LIG) photoelectrode. Specifically, the ZnO/LIG photoelectrode was synthesized in situ by a laser direct writing (LDW) technique. In the presence of TOB, it reacted with HP1 and HP2 and the DNA walker response was activated to form a stable hemin/G-quadruplex. Furthermore, hemin induced a polarity shift in the photocurrent signal. The developed analytical platform exhibited excellent photoelectron transport performance of ZnO/LIG, the signal amplification effect of the DNA walker strategy, and the photocurrent-polarity-switching ability of hemin. Therefore, it demonstrated satisfying photocurrent responses to the target TOB within the working range of 20 nM-1.0 µM at a low detection limit of 5.43 nM. The PEC platform exhibited good stability, reproducibility, sufficient sensitivity and high selectivity for complex experimental samples. Moreover, the photocurrent-polarity-switching PEC biosensor improved the anti-interference ability and avoided false positives or negatives.


Assuntos
Técnicas Biossensoriais , Grafite , Óxido de Zinco , Técnicas Eletroquímicas , Hemina , Reprodutibilidade dos Testes , DNA/genética , Técnicas Biossensoriais/métodos
7.
Sci Total Environ ; 916: 170308, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272088

RESUMO

With the rise in global plastic production and agricultural demand, the released microplastics (MPs) have increasingly influenced the elemental cycles of soils, leading to notable effects on greenhouse gas emissions. Despite initial research, there remains a gap in establishing a detailed modeling approach that comprehensively explores the impacts of MPs on GHG emissions. Herein, we utilized literature mining to assemble a comprehensive dataset examining the interplays between MPs and emissions of CO2, CH4, and N2O. Five automated machine learning frameworks were employed for predictive modeling. The GAMA framework was particularly effective in predicting CO2 (Q2 = 0.946) and CH4 (Q2 = 0.991) emissions. The Autogluon framework provided the most accurate prediction for N2O emission, though it exhibited signs of overfitting. Interpretability analysis indicated that the type of MPs significantly influenced CO2 emission. Degradable MPs (i.e., polyamide) inherently led to elevated CO2 emission, and the environmental aging further exacerbated this effect. Although both linear and nonlinear correlations between MPs and CH4 emission were not identified, the incorporation of specific MPs that elevate soil pH, augment soil water retention, and cultivate anaerobic conditions may potentially elevate soil CH4 emission. This research underscores the profound influence of MPs on soil GHG emissions, providing vital insights for shaping agricultural policies and soil management practices in the context of escalating plastic use.

8.
Anal Chim Acta ; 1257: 341126, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37062561

RESUMO

Self-powered photocatalytic fuel cell (PFC)-based sensors incorporating bioelement recognition with fuel concentration-dependent output power have been developed for electrochemical analysis, but most involve poor energy conversion efficiency and are unsuitable for routine use. Herein, a self-powered and self-checking PFC bioanalysis platform under visible light for ultrasensitive screening of Ochratoxin A (OTA) was designed. Specifically, the self-powered photocatalytic fuel cell-based sensor was comprised of a photoanode fabricated with MXenes (Ti3C2)-TiO2 and a cathode modified with Prussian blue (PB). To realize the high-performance of OTA detection, mesoporous silica nanoparticles (MSNs) were used as nanocontainers to load glucose, and aptamers were assembled on the surface of MSNs as dual-gated molecules to form signal probes. The reaction of analyte OTA with OTA aptamer was greater than the force between OTA aptamer and MSN, resulting in the release of glucose from MSNs. The released glucose was photo-oxidized by Ti3C2-TiO2 under visible light illumination and used as an electron acceptor to reduce PB, resulting in a high cell output response with a maximum output power (Pmax) of 23.516 µW cm-2. Meanwhile, the electrochromic PB enabled colorimetric detection of OTA with self-checking. The self-powered Ti3C2-TiO2-based PFC with target-recognition cargo release system exhibited superior analytical performance toward OTA in the range of 0.2 ppb-20 ppb and limit of detection (LOD) down to 0.0587 ppb. Additionally, excellent stability, rapid response, and exquisite selectivity for real samples (beer) was acceptable, providing an efficient approach in food safety monitoring.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas , Ocratoxinas , Glucose/química , Nanopartículas/química , Limite de Detecção , Ocratoxinas/análise , Dióxido de Silício , Técnicas Biossensoriais/métodos , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas
9.
Front Psychol ; 13: 1008982, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405124

RESUMO

Organizational sustainability in the form of environmental management and sustainable production is becoming more important for small and medium-sized enterprises (SMEs) throughout the world. This research evaluates the factors affecting the understanding of the CEO's and managers' intention to adopt practices of green supply chain management (GSCM) and clean innovation technology (CIT) in the manufacturing SMEs of Pakistan. This empirical research identifies key determinants influencing the adoption of GSCM practices. Using structural equation modeling (SEM), we selected a sample size of 350 different manufacturing firms in Pakistan. The results of the study revealed that six factors, namely, environmental, government, organization, suppliers, market, and operational factors, significantly influence the intention to adopt GSCM and positively impact sustainable production. The study's findings reveal that market and operational factors are highly significant for adopting GSCM practices at a p-value of 0.05. Environmental and organizational factors are equally significant to adopt GSCM practices at a p-value of 0.10. This research also analyzed CIT as a moderator between environmental, government, organization, customer, supplier, economic, market, and operational factors in the context of Pakistan. Hypotheses H9a, H9b, H9f, and H9g were validated and support the use of CIT to boost enterprise production and consumption. The research findings would help policymakers understand how to implement GSCM practices and guide enterprises to implement GSCM and CIT practices for enhancing enterprise performance and environmental sustainability.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35682364

RESUMO

Due to increasingly serious environmental pollution problems and governments' strengthening of environmental impact supervision, manufacturing companies are seeking green production methods, implementing carbon trading systems, and promoting the trend towards green remanufacturing. Thus, this paper introduces green factors to the existing closed-loop supply chain network models and studies the impact of carbon trading, green innovation efforts, and green consumers on the choice between two remanufacturing strategies: an in-house remanufacturing strategy and an authorized remanufacturing strategy. The results concerning the choice of the remanufacturing strategy are as follows: from the perspective of obtaining more profits, when the carbon trading price is low, the companies choose the authorized remanufacturing strategy; when the carbon trading price is high, the companies choose to remanufacture by themselves. For all the green innovation efforts and the proportions of green consumers, when the recovery rate of the used product is low, the companies choose to remanufacture by themselves; when the recovery rate of the used product is high, the companies choose the authorized remanufacturing strategy.


Assuntos
Carbono , Comércio , Meio Ambiente
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