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1.
Nano Lett ; 24(22): 6683-6688, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38767925

RESUMO

Two-dimensional (2D) ferroelectrics promise ultrathin flexible nanoelectronics, typically utilizing a metal-ferroelectric-metal sandwich structure. Electrodes can either contribute free carriers to screen the depolarization field, enhancing nanoscale ferroelectricity, or induce charge doping, disrupting the long-range crystalline order. We explore electrodes' dual roles in 2D ferroelectric capacitors, supported by first-principles calculations covering a range of electrode work functions. Our results reveal volcano-type relationships between ferroelectric-electrode binding affinity and work function, which are further unified by a quadratic scaling between the binding energy and the transferred interfacial charge. At the monolayer limit, charge transfer dictates the ferroelectric stability and switching properties. This general characteristic is confirmed in various 2D ferroelectrics including α-In2Se3, CuInP2S6, and SnTe. As the ferroelectric layer's thickness increases, the capacitor stability evolves from a charge-transfer-dominated state to a screening-dominated state. The delicate interplay between these two effects has important implications for 2D ferroelectric capacitor applications.

2.
ACS Sens ; 9(5): 2653-2661, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38710540

RESUMO

Fast and reliable semiconductor hydrogen sensors are crucially important for the large-scale utilization of hydrogen energy. One major challenge that hinders their practical application is the elevated temperature required, arising from undesirable surface passivation and grain-boundary-dominated electron transportation in the conventional nanocrystalline sensing layers. To address this long-standing issue, in the present work, we report a class of highly reactive and boundary-less ultrathin SnO2 films, which are fabricated by the topochemical transformation of 2D SnO transferred from liquid Sn-Bi droplets. The ultrathin SnO2 films are purposely made to consist of well-crystallized quasi-2D nanograins with in-plane grain sizes going beyond 30 nm, whereby the hydroxyl adsorption and grain boundary side-effects are effectively suppressed, giving rise to an activated (101)-dominating dangling-bond surface and a surface-controlled electrical transportation with an exceptional electron mobility of 209 cm2 V-1 s-1. Our work provides a new cost-effective strategy to disruptively improve the gas reception and transduction of SnO2. The proposed chemiresistive sensors exhibit fast, sensitive, and selective hydrogen sensing performance at a much-reduced working temperature of 60 °C. The remarkable sensing performance as well as the simple and scalable fabrication process of the ultrathin SnO2 films render the thus-developed sensors attractive for long awaited practical applications in hydrogen-related industries.


Assuntos
Hidrogênio , Compostos de Estanho , Compostos de Estanho/química , Hidrogênio/química , Hidrogênio/análise , Propriedades de Superfície , Gases/análise , Gases/química , Nanoestruturas/química , Semicondutores
3.
Patterns (N Y) ; 5(5): 100969, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38800361

RESUMO

Understanding the cellular composition of a disease-related tissue is important in disease diagnosis, prognosis, and downstream treatment. Recent advances in single-cell RNA-sequencing (scRNA-seq) technique have allowed the measurement of gene expression profiles for individual cells. However, scRNA-seq is still too expensive to be used for large-scale population studies, and bulk RNA-seq is still widely used in such situations. An essential challenge is to deconvolve cellular composition for bulk RNA-seq data based on scRNA-seq data. Here, we present DeepDecon, a deep neural network model that leverages single-cell gene expression information to accurately predict the fraction of cancer cells in bulk tissues. It provides a refining strategy in which the cancer cell fraction is iteratively estimated by a set of trained models. When applied to simulated and real cancer data, DeepDecon exhibits superior performance compared to existing decomposition methods in terms of accuracy.

4.
Front Oncol ; 14: 1344662, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800373

RESUMO

Minimally invasive esophagectomy for cancer surgery remains associated with significant morbidity and surgical complications across the globe. Non-intubation video-assisted thoracic surgery (NIVATS) has been successfully employed in lung resection in recent years, but there are few reported cases with regard to the safety and feasibility of this approach in radical esophagectomy for patients with esophageal cancers. We present 4 consecutive cases with esophageal squamous cell carcinoma (ESCC) who received minimally invasive McKeown's esophagectomy under non-intubation general anesthesia from November 2022 to April 2023. All these patients were aged from 55 to 75 years old and were pathologically diagnosed with ESCC. All procedures of McKeown's esophagectomy in these patients were completed with non-invasive ventilation by laryngeal mask-assisted anesthesia. Operation duration ranged from 185 to 395 minutes and the estimated blood loss ranged from 25 to 60 ml in these 4 cases. No severe hypoxia was observed and transient hypercapnia was resolved intraoperatively. None of them was converted to endotracheal intubation with mechanical ventilation or to thoracotomy. The number of retrieved lymph nodes in mediastinum were 21-27 and all patients received R0 surgery with pathological stage as T1bN0M0 to T3N2M0. There was no serious complication (Clavien-Dindo grade III-IV) observed perioperatively and they were all discharged 11-14 days after the surgery with resumption of oral feeding. They are all alive without tumor recurrence at the date of data collection. The safety and efficacy of minimally invasive esophagectomy with non-invasive ventilation by laryngeal mask-assisted anesthesia for patients with ESCC are warranted for explored in a larger cohort study.

5.
Mol Cancer Ther ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648067

RESUMO

We recently reported that resistance to PD-1-blockade in a refractory lung cancer-derived model involved increased collagen deposition and the collagen-binding inhibitory receptor leukocyte-associated immunoglobulin-like receptor 1 (LAIR1), and thus we hypothesized that LAIR1 and collagen cooperated to suppress therapeutic response. Here, we report LAIR1 is associated with tumor stroma and is highly expressed by intratumoral myeloid cells in both human tumors and mouse models of cancer. Stroma-associated myeloid cells exhibit a suppressive phenotype and correlate with LAIR1 expression in human cancer. NGM438, a novel humanized LAIR1 antagonist monoclonal antibody, elicits myeloid inflammation and allogeneic T cell responses by binding to LAIR1 and blocking collagen engagement. Further, a mouse-reactive NGM438 surrogate antibody sensitized refractory KP mouse lung tumors to anti-PD-1 therapy and resulted in increased intratumoral CD8+ T cell content and inflammatory gene expression. These data place LAIR1 at the intersection of stroma and suppressive myeloid cells and support the notion that blockade of the LAIR1/collagen axis can potentially address resistance to checkpoint inhibitor therapy in the clinic.

6.
Environ Res ; 252(Pt 2): 118960, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636648

RESUMO

Conventional plastics are inherently difficult to degrade, causing serious plastic pollution. With the development of society, biodegradable plastics (BPs) are considered as an alternative to traditional plastics. However, current research indicated that BPs do not undergo complete degradation in natural environments. Instead, they may convert into biodegradable microplastics (BMPs) at an accelerated rate, thereby posing a significant threat to environment. In this paper, the definition, application, distribution, degradation behaviors, bioaccumulation and biomagnification of BPs were reviewed. And the impacts of BMPs on soil and marine ecosystems, in terms of physicochemical property, nutrient cycling, microorganisms, plants and animals were comprehensively summarized. The effects of combined exposure of BMPs with other pollutants, and the mechanism of ecotoxicity induced by BMPs were also addressed. It was found that BMPs reduced pH, increased DOC content, and disrupted the nitrification of nitrogen cycle in soil ecosystem. The shoot dry weight, pod number and root growth of soil plants, and reproduction and body length of soil animals were inhibited by BMPs. Furthermore, the growth of marine plants, and locomotion, body length and survival of marine animals were suppressed by BMPs. Additionally, the ecotoxicity of combined exposure of BMPs with other pollutants has not been uniformly concluded. Exposure to BMPs induced several types of toxicity, including neurotoxicity, gastrointestinal toxicity, reproductive toxicity, immunotoxicity and genotoxicity. The future calls for heightened attention towards the regulation of the degradation of BPs in the environment, and pursuit of interventions aimed at mitigating their ecotoxicity and potential health risks to human.


Assuntos
Microplásticos , Microplásticos/toxicidade , Animais , Poluentes do Solo/toxicidade , Plásticos Biodegradáveis/toxicidade , Oceanos e Mares , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Solo/química , Ecossistema
7.
Opt Express ; 32(6): 9995-10004, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571222

RESUMO

We present a design of middle-infrared modulation absorbers based on vanadium dioxide (VO2). By using the electron beam evaporation technique, the Ag/SiO2/VO2/Ag/VO2 multilayer structure can achieve double band strong absorption in the mid-infrared, and dynamically adjust the absorption performance through VO2. The simulation results demonstrate a remarkable absorption rate of 91.8% and 98.9% at 9.09 µm and 10.25 µm, respectively. The high absorption is elucidated by analyzing the field strength distribution in each layer. Meanwhile, based on the phase change characteristics of VO2, the absorber has exceptional thermal regulation, with a remarkable 78% heat regulation range in the mid-infrared band. The size altering of the absorbing layer is effective in enhancing and optimizing the structure's absorption performance. The structure is used to characterize probe molecules of CV and R6 G by mid-infrared spectroscopy, which illustrates an impressive limit of detection (LOD) of 10-7 M for both substances. These results provide valuable insights for designing future high-performance tunable optical devices.

8.
Environ Pollut ; 349: 123927, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38582184

RESUMO

The recovery phase of mangrove seedlings in coastal wetland ecosystems can be negatively affected by exposure to external pollutants. This study aimed to investigate the impact of microplastics (MPs) influx, specifically polystyrene (PS) and polymethyl methacrylate (PMMA), on the growth of Aegiceras corniculatum seedlings and their accumulation of heavy metals (HMs). PS and PMMA significantly increased HMs accumulation (up to 21.0-548%), particularly in the roots of seedlings, compared to the control treatment (CK). Additionally, elevated activities of malondialdehyde and catalase enzymes were observed in the leaves of seedlings, while peroxidase enzyme activity decreased. Topological analysis of the root sediment microbiota coexistence network revealed that the modularization data increased from 0.69 (CK treatment) to 1.07 (PS treatment) and 5.11 (PMMA treatment) under the combined stress of MPs and HMs. This suggests that the introduction of MPs intensifies microbial modularization. The primary cause of increased HMs accumulation in plants is the MPs input, which influences the secretion of organic acids by plants and facilitates the shift of HMs in sediment to bioavailable states. Furthermore, changes in microbial clustering may also contribute to the elevated HMs accumulation in plants. This study provides valuable insights into the effects of external pollutants on mangrove seedlings and offers new perspectives for the preservation and restoration of mangrove coastal wetlands.


Assuntos
Metais Pesados , Microplásticos , Plântula , Poluentes Químicos da Água , Áreas Alagadas , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Plântula/metabolismo , Microplásticos/metabolismo , Monitoramento Ambiental/métodos , Primulaceae/metabolismo , Sedimentos Geológicos/química
9.
Sci Total Environ ; 926: 171809, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38513845

RESUMO

Soil cadmium (Cd) can affect crop growth and food safety, and through the enrichment in the food chain, it ultimately poses a risk to human health. Reducing the re-mobilization of Cd caused by the release of protons and acids by crops and microorganisms after stabilization is one of the significant technical challenges in agricultural activities. This study aimed to investigate the re-mobilization of stabilized Cd within the clay mineral-bound fraction of soil and its subsequent accumulation in crops utilizing nitrogen ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N), at 60 and 120 mg kg-1. Furthermore, the study harvested root exudates at various growth stages to assess their direct influence on the re-mobilization of stabilized Cd and to evaluate the indirect effects mediated by soil microorganisms. The results revealed that, in contrast to the NO3--N treatment, the NH4+-N treatment significantly enhanced the conversion of clay mineral-bound Cd in the soil to NH4NO3-extractable Cd. It also amplified the accumulation of Cd in edible amaranth, with concentrations in roots and shoots rising from 1.7-6.0 mg kg-1 to 4.3-9.8 mg kg-1. The introduction of NH4+-N caused a decrease in the pH value of the rhizosphere soil and stimulated the production and secretion organic and amino acids, such as oxalic acid, lactic acid, stearic acid, succinic acid, and l-serine, from the crop roots. Furthermore, compared to NO3--N, the combined interaction of root exudates with NH4+-N has a more pronounced impact on the abundance of microbial genes associated with glycolysis pathway and tricarboxylic acid cycle, such as pkfA, pfkB, sucB, sucC, and sucD. The effects of NH4+-N on crops and microorganisms ultimately result in a significant increase in the re-mobilization of stabilized Cd. However, the simulated experiments showed that microorganisms only contribute to 3.8-6.6 % of the re-mobilization of clay mineral-bound Cd in soil. Therefore, the fundamental strategy to inhibit the re-mobilization of stabilized Cd in vegetable cultivation involves the regulation of proton and organic acid secretion by crops.


Assuntos
Poluentes do Solo , Solo , Humanos , Solo/química , Cádmio/análise , Argila , Nitrogênio/metabolismo , Compostos Orgânicos/metabolismo , Produtos Agrícolas/metabolismo , Minerais/metabolismo , Fertilização , Poluentes do Solo/análise
10.
J Multidiscip Healthc ; 17: 1291-1302, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524859

RESUMO

Background: Workplace violence (WPV) had become an important issue that endangered the occupational safety of psychiatric nurses. A growing number of studies showed positive post-traumatic growth (PTG) resulting from coping with trauma. Objective: To investigate the characteristics of PTG in psychiatric nurses who experienced violence in the workplace and analyze its influencing factors. Methods: A total of 1202 psychiatric nurses participated in the study. From October 2022 to December 2022, this cross-sectional study collected data on psychiatric nurses from five tertiary hospitals in Guangdong Province, China. Twenty-item Chinese version post-traumatic growth inventory (PTGI), Jefferson Scale of Empathy Health Professional (JSE-HP), Confidence in Coping with Patient Aggression Instrument (CCPAI), Post-traumatic Stress Disorder Checklist-Civilian Version (PCL-C), and Connor-Davidson Resilience Scale (CD-RISC) measured PTG level, empathy, the confidence in coping with WPV, post-traumatic stress disorder, and resilience, respectively. Bivariate analysis and multiple linear regression explored potential influencing factors of PTG. This study complies with the EQUATOR (STROBE) checklist. Results: The sample was composed of a total of 1202 psychiatric nurses suffering from WPV. The average score of PTGI in psychiatric nurses was above average (65.75 points; SD = 20.20). Linear regression analyses showed from single-child family (ß=0.052,95% CI=0.342,5.409, P<0.05), education background (ß=0.108,95% CI=1.833,5.097, P<0.001), the confidence in coping with patient aggression (ß=0.106,95% CI=1.385,4.317, P<0.001), empathy (ß=0.057,95% CI=0.312,4.374, P<0.05), and resilience (ß=0.484,95% CI=7.737,9.575, P<0.001) were associated with PTG level. Conclusion: Psychiatric nurses who were non-single child, had received higher education, had confidence in coping with patient aggression, had good resilience and strong empathy were prone to PTG after experiencing WPV. The study findings could help hospitals and nursing managers identify vulnerable individuals and take early intervention measures against such populations.

11.
BMJ Open ; 14(3): e076797, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508629

RESUMO

Long-term outcome and 'health-related quality of life' (HRQoL) following hospitalisation for COVID-19-related severe acute respiratory infection (SARI) is limited. OBJECTIVE: To assess the impact of HRQoL in patients hospitalised with COVID-19-related SARI at 1 year post discharge, focusing on the potential impact of age, frailty, and disease severity. METHOD: Routinely collected outcome data on 1207 patients admitted with confirmed COVID-19 related SARI across all three secondary care sites in our NHS trust over 3 months were assessed in this retrospective cohort study. Of those surviving 1 year, we prospectively collected 36-item short form (SF-36) HRQoL questionnaires, comparing three age groups (<49, 49-69, and the over 69-year-olds), the relative impact of frailty (using the Clinical Frailty Score; CFS), and disease severity (using National Early Warning Score; NEWS) on HRQoL domains. RESULTS: Overall mortality was 46.5% in admitted patients. In our SF-36 cohort (n=169), there was a significant reduction in all HRQoL domains versus normative data; the most significant reductions were in the physical component (p<0.001) across all ages and the emotional component (p<0.01) in the 49-69 year age group, with age having no additional impact on HRQoL. However, there was a significant correlation between physical well-being versus CFS (the correlation coefficient=-0.37, p<0.05), though not NEWS, with no gender difference observed. CONCLUSION: There was a significant reduction in all SF-36 domains at 1 year. Poor CFS at admission was associated with a significant and prolonged impact on physical parameters at 1 year. Age had little impact on the severity of HRQoL, except in the domains of physical functioning and the overall physical component.


Assuntos
COVID-19 , Fragilidade , Humanos , Qualidade de Vida/psicologia , Estudos Retrospectivos , Alta do Paciente , Fragilidade/complicações , COVID-19/complicações , Assistência ao Convalescente , Hospitalização , Gravidade do Paciente
12.
bioRxiv ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38529493

RESUMO

The recognition and binding of nucleic acids (NAs) by proteins depends upon complementary chemical, electrostatic and geometric properties of the protein-NA binding interface. Structural models of protein-NA complexes provide insights into these properties but are scarce relative to models of unbound proteins. We present a deep learning approach for predicting protein-NA binding given the apo structure of a protein (PNAbind). Our method utilizes graph neural networks to encode spatial distributions of physicochemical and geometric properties of the protein molecular surface that are predictive of NA binding. Using global physicochemical encodings, our models predict the overall binding function of a protein and can discriminate between specificity for DNA or RNA binding. We show that such predictions made on protein structures modeled with AlphaFold2 can be used to gain mechanistic understanding of chemical and structural features that determine NA recognition. Using local encodings, our models predict the location of NA binding sites at the level of individual binding residues. Binding site predictions were validated against benchmark datasets, achieving AUROC scores in the range of 0.92-0.95. We applied our models to the HIV-1 restriction factor APOBEC3G and show that our predictions are consistent with experimental RNA binding data.

13.
Chem Sci ; 15(5): 1782-1788, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38303930

RESUMO

The flexoelectric effect, which refers to the mechanical-electric coupling between strain gradient and charge polarization, should be considered for use in charge production for catalytically driving chemical reactions. We have previously revealed that halide perovskites can generate orders of higher magnitude flexoelectricity under the illumination of light than in the dark. In this study, we report the catalytic hydrogen production by photo-mechanical coupling involving the photoflexoelectric effect of flexible methylammonium lead iodide (MAPbI3) nanowires (NWs) in hydrogen iodide solution. Upon concurrent light illumination and mechanical vibration, large strain gradients were introduced in flexible MAPbI3 NWs, which subsequently induced significant hydrogen generation (at a rate of 756.5 µmol g-1 h-1, surpassing those values from either photo- or piezocatalysis of MAPbI3 nanoparticles). This photo-mechanical coupling strategy of mechanocatalysis, which enables the simultaneous utilization of multiple energy sources, provides a potentially new mechanism in mechanochemistry for highly efficient hydrogen production.

14.
Cancer Immunol Res ; 12(5): 592-613, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393969

RESUMO

Solid tumors are dense three-dimensional (3D) multicellular structures that enable efficient receptor-ligand trans interactions via close cell-cell contact. Immunoglobulin-like transcript (ILT)2 and ILT4 are related immune-suppressive receptors that play a role in the inhibition of myeloid cells within the tumor microenvironment. The relative contribution of ILT2 and ILT4 to immune inhibition in the context of solid tumor tissue has not been fully explored. We present evidence that both ILT2 and ILT4 contribute to myeloid inhibition. We found that although ILT2 inhibits myeloid cell activation in the context of trans-engagement by MHC-I, ILT4 efficiently inhibits myeloid cells in the presence of either cis- or trans-engagement. In a 3D spheroid tumor model, dual ILT2/ILT4 blockade was required for the optimal activation of myeloid cells, including the secretion of CXCL9 and CCL5, upregulation of CD86 on dendritic cells, and downregulation of CD163 on macrophages. Humanized mouse tumor models showed increased immune activation and cytolytic T-cell activity with combined ILT2 and ILT4 blockade, including evidence of the generation of immune niches, which have been shown to correlate with clinical response to immune-checkpoint blockade. In a human tumor explant histoculture system, dual ILT2/ILT4 blockade increased CXCL9 secretion, downregulated CD163 expression, and increased the expression of M1 macrophage, IFNγ, and cytolytic T-cell gene signatures. Thus, we have revealed distinct contributions of ILT2 and ILT4 to myeloid cell biology and provide proof-of-concept data supporting the combined blockade of ILT2 and ILT4 to therapeutically induce optimal myeloid cell reprogramming in the tumor microenvironment.


Assuntos
Antígenos CD , Receptor B1 de Leucócitos Semelhante a Imunoglobulina , Glicoproteínas de Membrana , Células Mieloides , Receptores Imunológicos , Microambiente Tumoral , Receptores Imunológicos/metabolismo , Animais , Humanos , Camundongos , Microambiente Tumoral/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Glicoproteínas de Membrana/metabolismo , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo
15.
Environ Int ; 183: 108369, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070437

RESUMO

Nitrous oxide (N2O) emission during the sewage treatment process is a serious environmental issue that requires attention. However, the N2O emission in constructed wetlands (CWs) as affected by different nitrogen forms in influents remain largely unknown. This study investigated the N2O emission profiles driven by microorganisms in CWs when exposed to two typical nitrogen sources (NH4+-N or NO3--N) along with different carbon source supply (COD/N ratios: 3, 6, and 9). The results showed that CWs receiving NO3--N caused a slight increase in total nitrogen removal (by up to 11.8 %). This increase was accomplished by an enrichment of key bacteria groups, including denitrifiers, dissimilatory nitrate reducers, and assimilatory nitrate reducers, which enhanced the stability of microbial interaction. Additionally, it led to a greater abundance of denitrification genes (e.g., nirK, norB, norC, and nosZ) as inferred from the database. Consequently, this led to a gradual increase in N2O emission from 66.51 to 486.77 ug-N/(m2·h) as the COD/N ratio increased in CWs. Conversely, in CWs receiving NH4+-N, an increasing influent COD/N ratio had a negative impact on nitrogen biotransformation. This resulted in fluctuating trend of N2O emissions, which decreased initially, followed by an increase at later stage (with values of 122.87, 44.00, and 148.59 ug-N/(m2·h)). Furthermore, NH4+-N in the aquatic improved the nitrogen uptake by plants and promoted the production of more root exudates. As a result, it adjusted the nitrogen-transforming function, ultimately reducing N2O emissions in CWs. This study highlights the divergence in microbiota succession and nitrogen transformation in CWs induced by nitrogen form and COD/N ratio, contributing to a better understanding of the microbial mechanisms of N2O emission in CWs with NH4+-N or NO3--N at different COD/N ratios.


Assuntos
Microbiota , Óxido Nitroso , Óxido Nitroso/metabolismo , Desnitrificação , Áreas Alagadas , Nitrogênio , Nitratos
16.
Sci Total Environ ; 912: 169228, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38101634

RESUMO

Microplastics (MPs) exist widely in the environment and can enter the human body indirectly through the food chain or directly through inhalation or ingestion. The primary organ that MPs contaminated food or water enters the human body through the digestive tract is the stomach. However, at present, the effects of MPs on the stomach and the related mechanism remain unclear. In this study, our results indicated that 50 nm and 250 nm polystyrene MPs (PS-MPs) at environmental related dose significantly decreased stomach organ coefficient, inhibited gastric juice secretion and mucus secretion, disrupted gastric barrier function and suppressed antioxidant ability in mice. In vitro experiments showed that PS-MPs inhibited cell viability, increased ROS generation, and induced apoptosis through mitochondria-dependent pathway. Simultaneously, PS-MPs also decreased mitochondrial membrane potential, ATP level, disrupted mitochondrial kinetic homeostasis, and activated P62 / Nrf2 / Keap1 pathway. Furthermore, blocking ROS (NAC) partially alleviated ROS and apoptosis caused by PS-MPs. Based on above findings, the potential adverse outcome pathway (AOP) of PS-MPs-caused gastric toxicity was proposed which provides a new insight into the risk assessment of MP related gastric damage. Our study unveils the gastric injury induced by PS MPs is dependent on ROS - mediated P62 / Nrf2 / Keap1 signaling pathway, and provides scientific basis for further exploration the mechanism of gastric toxicity of PS MPs.


Assuntos
Microplásticos , Fator 2 Relacionado a NF-E2 , Humanos , Animais , Camundongos , Poliestirenos/toxicidade , Espécies Reativas de Oxigênio , Proteína 1 Associada a ECH Semelhante a Kelch , Plásticos , Estresse Oxidativo , Estômago
17.
Chem Commun (Camb) ; 59(91): 13643-13646, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37905454

RESUMO

An aminoquinolate diarylboron (AQDAB) and tetrabutylammonium iodide (TBAI) co-catalyzed photoredox process for N-functionalization of NH-sulfoximines/sulfonimidamides has been successfully developed. This protocol can afford the corresponding N-sulfenylated and N-phosphonylated products in good to excellent yields under conditions without metallic (photo)catalysts, external oxidants, or acidic/basic additives. A wide range of functional groups are tolerated, and the N-phosphonylated products of NH-sulfonimidamides have been reported for the first time.

18.
Adv Mater ; : e2305924, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698463

RESUMO

Utilizing renewable biomass as a substitute for fossil resources to produce high-value chemicals with a low carbon footprint is an effective strategy for achieving a carbon-neutral society. Production of chemicals via single-atom catalysis is an attractive proposition due to its remarkable selectivity and high atomic efficiency. In this work, a supramolecular-controlled pyrolysis strategy is employed to fabricate a palladium single-atom (Pd1 /BNC) catalyst with B-doped Pd-Nx atomic configuration. Owing to the meticulously tailored local coordination microenvironment, the as-synthesized Pd1 /BNC catalyst exhibits remarkable conversion capability for a wide range of biomass-derived aldehydes/ketones. Thorough characterizations and density functional theory calculations reveal that the highly polar metal-N-B site, formed between the central Pd single atom and its adjacent N and B atoms, promotes hydrogen activation from the donor (reductants) and hydrogen transfer to the acceptor (C═O group), consequently leading to exceptional selectivity. This system can be further extended to directly synthesize various aromatic and furonic amines from renewable lignocellulosic biomass, with their greenhouse gas emission potentials being negative in comparison to those of fossil-fuel resource-based amines. This research presents a highly effective and sustainable methodology for constructing C─N bonds, enabling the production of a diverse array of amines from carbon-neutral biomass resources.

19.
J Phys Chem Lett ; 14(38): 8563-8570, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37724994

RESUMO

Nanomaterials of halide perovskites have attracted increasing attention for their remarkable potential in optoelectronic devices, but their instability to environmental factors is the core issue impeding their applications. In this context, the microscopic understanding of their structural degradation mechanisms upon external stimuli remains incomplete. Herein, we took an emerging member of this material family, Cs4PbBr6 nanocrystals (NCs), as an example and investigated the degradation pathways as well as underlying mechanisms under an electron beam by using in situ transmission electron microscopy. Our atomic-scale study identified the distinct degradation stages for the NCs toward interesting coffee-ring PbBr2 structures, which are caused by the organic surface capping agents as well as surface energy of NCs. Our findings present a fundamental insight for the degradation of halide perovskite NCs and may provide indispensable guidance for their structural design and stability improvement.

20.
J Hazard Mater ; 460: 132327, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37639785

RESUMO

Cadmium (Cd) accumulation in edible plant tissues poses a serious threat to human health through the food chain. Assessing the availability of soil Cd is crucial for evaluating associated environmental risks. However, existing experimental methods and traditional models are time-consuming and inefficient. In this study, we developed machine learning models to predict soil available Cd based on soil properties, using a dataset comprising 585 data points covering 585 soils. Traditional machine learning models exhibited prediction values beyond the theoretical range, urging the need for alternative approaches. To address this, different models were tested, and the post-constraint eXtreme Gradient Boosting (XGBoost) model was found to possess the best predictive performance (R2 =0.81) outperform traditional linear regression model in terms of accuracy. Furthermore, we explored the relationship between soil available Cd and wheat grain Cd and rice grain Cd. Linear regression models were developed using 302 data points for wheat and 563 data points for rice. Results demonstrated a significant correlation between soil available Cd and wheat grain Cd (R2 =0.487) as well as rice grain Cd (R2 =0.43).


Assuntos
Cádmio , Oryza , Humanos , Grão Comestível , Cadeia Alimentar , Aprendizado de Máquina , Solo , Triticum
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