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2.
Environ Int ; 185: 108550, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452466

RESUMO

Nanoscale zero-valent iron (Fe) is a promising nanomaterial for remediating heavy metal-contaminated soils. Melatonin (MT) is essential to alleviate environmental stress in plants. However, the conjunction effects of Fe and MT (FeMT) on rice Cd, As accumulation and the mechanism of soil chemical and microbial factors interaction are unclear. Here, a pot experiment was conducted to evaluated the effects of the FeMT for rice Cd, As accumulation and underlying mechanisms. The findings showed that FeMT significantly reduced grains Cd by 92%-87% and As by over 90%, whereas improving grains Fe by over 213%. Soil available-Cd and iron plaques-Cd (extracted by dithionite-citrate-bicarbonate solution, DCB-Cd) significantly regulated roots Cd, thus affected Cd transport to grains. Soil pH significantly affected soil As and DCB-As, which further influenced roots As uptake and the transport to shoots and grains. The interactions between the soil bacterial community and soil Fe, available Fe, and DCB-Fe together affected root Fe absorption and transportation in rice. FeMT significantly influenced rhizosphere soil bacterial α- and ß-diversity. Firmicutes as the dominant phylum exhibited a significant positive response to FeMT measure, and acted a key role in reducing soil Cd and As availability mainly by improving iron-manganese plaques. The increase of soil pH caused by FeMT was beneficial only for Actinobacteriota growth, which reduced Cd, As availability probably through complexation and adsorption. FeMT also showed greater potential in reducing human health and ecological risks by rice consumption and straw returning. These results showed the important role of both soil chemical and microbial factors in FeMT-mediated rice Cd, As reduction efficiency. This study opens a novel strategy for safe rice production and improvement of rice iron nutrition level in heavy-metals polluted soil, but also provides new insights into the intricate regulatory relationships among soil biochemistry, toxic elements, microorganism, and plants.


Assuntos
Melatonina , Metais Pesados , Oryza , Poluentes do Solo , Humanos , Ferro/química , Solo/química , Cádmio/análise , Melatonina/farmacologia , Oryza/química , Metais Pesados/análise , Bactérias , Poluentes do Solo/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-38502266

RESUMO

Graphene-based material is widely used to remove arsenic from water due to its layered structure with high surface area. Here, we have successfully synthesized Fe-La bimetallic modified graphite sheet materials to more efficiently remove As(III) from aqueous solution. The results showed that Fe-La-graphite sheets (FL-graphite sheets) have a larger specific surface area (194.28 m2·g-1) than graphite sheets (2.80 m2·g-1). The adsorption capacity of FL-graphite sheets for As(III) was 51.69 mg·g-1, which was higher than that of graphite sheets (21.91 mg·g-1), La-graphite sheets (26.06 mg·g-1), and Fe-graphite sheets (40.26 mg·g-1). The FL-graphite sheets conformed to the Freundlich and Dubinin-Radushkevich isotherm, and the maximum adsorption capacity was 53.62 mg·g-1. The removal process obeys intra-particle diffusion and pore diffusion for As(III). The results of batch adsorption experiments and characterization analyses demonstrated that oxidation, ligand exchange, and inner sphere complexation mechanisms involved in the adsorption of FL-graphite sheets to As(III) in comparison with graphite sheets. In addition, electrostatic attraction mechanism was found vital in the adsorption. Ecotoxicity assessment revealed that FL-graphite sheets have little influence on rice germination and growth, but reduced the toxicity of As(III) to rice. Therefore, the FL-graphite sheets have good practical application value in purifying As(III) polluted water with litter ecotoxicity.

4.
Micromachines (Basel) ; 15(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542640

RESUMO

Deterministic polishing based on jet electrochemical machining (Jet-ECM) is a stress-free machining method for low-rigidity and ultra-precision workpieces. The nozzle is equivalent to a special tool in deterministic polishing, and the workpiece material is removed using the mechanism of electrochemical dissolution at the position where the nozzle passes. By precisely regulating the nozzle's movement speed and dwell time, the quantity of material removed from the workpiece at a designated position can be finely adjusted. With this mechanism, the improvement of the workpiece shape accuracy can be achieved by planning the nozzle trajectory and nozzle movement speed. However, due to the positioning errors of the polishing device, the actual position of the nozzle may deviate from the theoretical position, resulting in errors in material removal amount, which affects the accuracy and stability of the polishing process. This study established a mathematical model to analyze the influence of nozzle positioning errors in deterministic polishing based on Jet-ECM. This model has been used to design a specific deterministic polishing device based on Jet-ECM. With the proposed deterministic polishing device, the surface shape of the workpiece is converged. The surface peak-to-valley (PV) value of the φ 50 mm workpiece (valid dimensions = 90% of the central region) indicated that the shape error of the surface was reduced from 2.67 µm to 1.24 µm in 34 min. The power spectral density (PSD) method was used to evaluate the height distribution and height characteristics of the workpiece surface. The results show that the low frequency spatial error is reduced significantly after processing. This study improves the accuracy of the stress-free deterministic polishing methods and further expands the use of deterministic polishing in industry.

5.
Comput Biol Med ; 170: 108067, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301513

RESUMO

BACKGROUND: Ocular Adnexal Lymphoma (OAL) is a non-Hodgkin's lymphoma that most often appears in the tissues near the eye, and radiotherapy is the currently preferred treatment. There has been a controversy regarding the prognostic factors for systemic failure of OAL radiotherapy, the thorough evaluation prior to receiving radiotherapy is highly recommended to better the patient's prognosis and minimize the likelihood of any adverse effects. PURPOSE: To investigate the risk factors that contribute to incomplete remission in OAL radiotherapy and to establish a hybrid model for predicting the radiotherapy outcomes in OAL patients. METHODS: A retrospective chart review was performed for 87 consecutive patients with OAL who received radiotherapy between Feb 2011 and August 2022 in our center. Seven image features, derived from MRI sequences, were integrated with 122 clinical features to form comprehensive patient feature sets. Chemometric algorithms were then employed to distill highly informative features from these sets. Based on these refined features, SVM and XGBoost classifiers were performed to classify the effect of radiotherapy. RESULTS: The clinical records of from 87 OAL patients (median age: 60 months, IQR: 52-68 months; 62.1% male) treated with radiotherapy were reviewed. Analysis of Lasso (AUC = 0.75, 95% CI: 0.72-0.77) and Random Forest (AUC = 0.67, 95% CI: 0.62-0.70) algorithms revealed four potential features, resulting in an intersection AUC of 0.80 (95% CI: 0.75-0.82). Logistic Regression (AUC = 0.75, 95% CI: 0.72-0.77) identified two features. Furthermore, the integration of chemometric methods such as CARS (AUC = 0.66, 95% CI: 0.62-0.72), UVE (AUC = 0.71, 95% CI: 0.66-0.75), and GA (AUC = 0.65, 95% CI: 0.60-0.69) highlighted six features in total, with an intersection AUC of 0.82 (95% CI: 0.78-0.83). These features included enophthalmos, diplopia, tenderness, elevated ALT count, HBsAg positivity, and CD43 positivity in immunohistochemical tests. CONCLUSION: The findings suggest the effectiveness of chemometric algorithms in pinpointing OAL risk factors, and the prediction model we proposed shows promise in helping clinicians identify OAL patients likely to achieve complete remission via radiotherapy. Notably, patients with a history of exophthalmos, diplopia, tenderness, elevated ALT levels, HBsAg positivity, and CD43 positivity are less likely to attain complete remission after radiotherapy. These insights offer more targeted management strategies for OAL patients. The developed model is accessible online at: https://lzz.testop.top/.


Assuntos
Neoplasias Oculares , Linfoma não Hodgkin , Humanos , Masculino , Pré-Escolar , Feminino , Estudos Retrospectivos , Quimiometria , Diplopia , Antígenos de Superfície da Hepatite B , Neoplasias Oculares/diagnóstico por imagem , Neoplasias Oculares/radioterapia , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/radioterapia , Linfoma não Hodgkin/patologia , Algoritmos
6.
Biomater Sci ; 12(2): 375-386, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37997042

RESUMO

There is a high demand from aging people for facial fillers with desirable biocompatibility and lasting filling effects to overcome facial depression. Novel injectable regenerated silk fibroin (RSF) microparticles were facilely printed from a glycidyl methacrylate-modified silk fibroin hydrogel to address this issue. The ß-sheet content and mechanical properties of the RSF hydrogel can be simply modulated by the number of freeze-thawing cycles, and the swelling rate of the RSF hydrogel in saline was negligible. The printed RSF microparticles were uniform, and their diameter was about 300-500 µm, which could be adjusted by the pore sizes of the printed screens. After the injection with a 26-gauge needle, the size distribution of RSF microparticles had no noticeable variation, suggesting that the microparticles could bear the shear strain without breaking during the injection. The in vitro experiments demonstrated that RSF not only had desirable biocompatibility but also facilitated fibroblast migration. The subcutaneous injection experiments demonstrated that the RSF microparticles formed a lasting spot in the injected site. The tissue sections revealed that the RSF microparticles were still distinct on week 8, and blood vessels formed around the microparticles. These promising data demonstrate that the printed RSF microparticles have great potential for facial rejuvenation.


Assuntos
Fibroínas , Humanos , Hidrogéis , Conformação Proteica em Folha beta , Injeções Subcutâneas , Congelamento , Seda
7.
Aquat Toxicol ; 267: 106808, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159456

RESUMO

Copper is an essential biometal for cell development and function, however, unbalanced copper homeostasis in T cell development and the underlying mechanisms are largely unexplored. Here, we use a zebrafish model to investigate the effect of copper overload in T cell development. We show that copper stressed zebrafish larvae exhibit a significant reduction in T cells with increased cell apoptosis and impaired cell proliferation. T cell progenitors, hematopoietic stem and progenitor cells, also exhibit increased cell apoptosis. Copper overload induces production of ROS and the down-regulations of its resistance genes foxos, and ectopic expression of foxo3a, ROS scavenger GSH, could both effectively rescue the reduction of T cells in copper overload larvae. Moreover, foxm1-cytoskeleton axis, parallel to ROS-foxo axis, also mediates the copper overload induced T cell developmental defects. Meanwhile, ROS destroys expression of cytoskeleton rather than of foxm1 in the cells to induce cell apoptosis and the impaired proliferation. The functional integrity of copper transporters cox17 and atp7b are required for copper stress in inducing T cell apoptosis and proliferation impairment. Our findings demonstrate that the down-stream ROS-foxo/cytoskeleton and foxm1-cytoskeleton signaling pathways contribute jointly to copper overload induced T cell apoptosis and proliferation defects, which are depend on the integral function of Cox17 and Atp7b, and provide new insight into the copper homeostasis in T lymphocyte development.


Assuntos
Cobre , Poluentes Químicos da Água , Animais , Cobre/toxicidade , Cobre/metabolismo , Peixe-Zebra/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/metabolismo , Poluentes Químicos da Água/toxicidade , Apoptose , Proliferação de Células
8.
Front Neuroinform ; 17: 1337766, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088986

RESUMO

[This corrects the article DOI: 10.3389/fninf.2023.1118419.].

9.
ACS Appl Nano Mater ; 6(21): 19639-19650, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37969784

RESUMO

Electrochemical synthesis has emerged as a promising approach for the large-scale production of graphene-based two-dimensional (2D) materials. Electrochemical intercalation of ions and molecules between graphite layers plays a key role in the synthesis of graphene with controllable thickness. However, there is still a limited understanding regarding the impact of intercalant molecules. Herein, we investigated a series of anionic species (i.e., ClO4-, PF6-, BF4-, HSO4-, CH3SO3-, and TsO-) and examined their wedging process between the weakly bonded layered materials driven by electrochemistry. By combining cyclic voltammetry, X-ray diffraction (XRD), and Raman spectroscopy, along with density functional theory (DFT) calculations, we found that stage-2 graphite intercalation compounds (GICs) can be obtained through intercalation of ClO4-, PF6-, or BF4- anions into the adjacent graphene bilayers. The anodic exfoliation step based on ClO4--GIC in (NH4)2SO4 (aq.) resulted in the formation of bilayer-rich (>57%) electrochemically exfoliated graphene oxide (EGO), with a high yield (∼85 wt %). Further, the physicochemical properties of these EGO can be readily customized through electrochemical reduction and modification with different surfactants. This versatility allows for precise tailoring of EGO, making it feasible for energy and electronic applications such as electrodes in electrochemical capacitors and functional composites in wearable electronics.

10.
Antioxidants (Basel) ; 12(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-38001770

RESUMO

Antimony (Sb) is a hazardous metal element that is potentially toxic and carcinogenic. Melatonin (MT) is an indole compound with antioxidant properties that plays an essential role in plant growth and alleviates heavy metal stresses. Nevertheless, little is known about the effects and mechanisms of exogenous MT action on rice under Sb stress. The aim of this experiment was to explore the mechanism of MT reducing Sb toxicity in rice via hydroponics. The results showed that Sb stress significantly inhibited the growth of rice, including biomass, root parameters, and root viability. Exogenous MT obviously alleviated the inhibition of Sb stress on seedling growth and increased biomass, root parameters, and root viability by 15-55%. MT significantly reduced the total Sb content in rice and the subcellular Sb contents in roots by nearly 20-40% and 12.3-54.2% under Sb stress, respectively. MT significantly decreased the contents of malondialdehyde (MDA, by nearly 50%), ROS (H2O2 and O2·-, by nearly 20-30%), and RNS (NO and ONOO-) in roots under Sb stress, thus reducing oxidative stress and cell membrane damage. Furthermore, MT reversed Sb-induced phytotoxicity by increasing the activities of antioxidant enzymes (SOD, POD, CAT, and APX) by nearly 15% to 50% and by regulating the AsA-GSH cycle. In conclusion, this study demonstrates the potential of MT to maintain redox homeostasis and reduce Sb toxicity in rice cells, decreasing the content of Sb in rice and thereby alleviating the inhibition of Sb on rice growth. The results provided a feasible strategy for mitigating Sb toxicity in rice.

11.
Adv Mater ; : e2306358, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37992728

RESUMO

The irregular expression or activity of enzymes in the human body leads to various pathological disorders and can therefore be used as an intrinsic trigger for more precise identification of disease foci and controlled release of diagnostics and therapeutics, leading to improved diagnostic accuracy, sensitivity, and therapeutic efficacy while reducing systemic toxicity. Advanced synthesis strategies enable the preparation of polymers with enzymatically activatable skeletons or side chains, while understanding enzymatically responsive mechanisms promotes rational incorporation of activatable units and predictions of the release profile of diagnostics and therapeutics, ultimately leading to promising applications in disease diagnosis and treatment with superior biocompatibility and efficiency. By overcoming the challenges, new opportunities will emerge to inspire researchers to develop more efficient, safer, and clinically reliable enzymatically activatable polymeric carriers as well as prodrugs.

12.
Nat Commun ; 14(1): 7406, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37973914

RESUMO

Major depressive disorder (MDD) is one of the most common and disabling mental disorders, and current strategies remain inadequate. Although mesenchymal stromal cells (MSCs) have shown beneficial effects in experimental models of depression, underlying mechanisms remain elusive. Here, using murine depression models, we demonstrated that MSCs could alleviate depressive and anxiety-like behaviors not due to a reduction in proinflammatory cytokines, but rather activation of dorsal raphe nucleus (DRN) 5-hydroxytryptamine (5-HT) neurons. Mechanistically, peripheral delivery of MSCs activated pulmonary innervating vagal sensory neurons, which projected to the nucleus tractus solitarius, inducing the release of 5-HT in DRN. Furthermore, MSC-secreted brain-derived neurotrophic factor activated lung sensory neurons through tropomyosin receptor kinase B (TrkB), and inhalation of a TrkB agonist also achieved significant therapeutic effects in male mice. This study reveals a role of peripheral MSCs in regulating central nervous system function and demonstrates a potential "lung vagal-to-brain axis" strategy for MDD.


Assuntos
Transtorno Depressivo Maior , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Masculino , Serotonina , Núcleo Dorsal da Rafe , Ansiedade/terapia
13.
BMC Surg ; 23(1): 309, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828530

RESUMO

BACKGROUND: There is no consensus on the optimal reconstruction technique after proximal gastrectomy. The purpose of this study was to retrospectively compare the surgical outcomes among esophagogastrostomy (EG) anastomosis, gastric tube (GT) reconstruction and double-tract (DT) reconstruction in patients who underwent laparoscopic proximal gastrectomy (LPG) to clarify the superior reconstruction method. METHODS: This study enrolled 164 patients who underwent LPG at the Northern Jiangsu People's Hospital in Jiangsu between January 2017 to January 2022 (EG: 51 patients; GT: 77 patients; DT: 36 patients). We compared the clinical and pathological characteristics, surgical features, postoperative complications, nutritional status, and quality of life (QOL) among the above three groups. RESULTS: Mean operative time was longer with the DT group than the remaining two groups (p = 0.001). With regard to postoperative complications, considerable differences in the postoperative reflux symptoms (p = 0.042) and reflux esophagitis (p = 0.040) among the three groups were found. For the nutritional status, total protein, hemoglobin and albumin reduction rates in the GT group were significantly higher than the other two groups at 12 months postoperatively. In the PGSAS-45, three assessment items were better in the DT group significantly compared with the esophageal reflux subscale (p = 0.047, Cohen's d = 0.44), dissatisfaction at the meal (p = 0.009, Cohen's d = 0.58), and dissatisfaction for daily life subscale (p = 0.012, Cohen's d = 0.56). CONCLUSIONS: DT after LPG is a valuable reconstruction technique with satisfactory surgical outcomes, especially regarding reduced reflux symptoms, improving the postoperative nutritional status and QOL.


Assuntos
Esofagite Péptica , Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Qualidade de Vida , Resultado do Tratamento , Estudos Retrospectivos , Laparoscopia/métodos , Gastrectomia/métodos , Anastomose Cirúrgica/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia
14.
J Econ Entomol ; 116(5): 1894-1901, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37676739

RESUMO

Genetically modified (GM) proteins in edible tissues of transgenic maize are of intense public concern. We provided a Cre/loxP-based strategy for manipulating the expression of transgenes in green tissues while locking them in nongreen tissues. First, the Cre gene was driven by the green tissue-specific promoter Zm1rbcS to generate transgenic maize KEY. Meanwhile, a gene cassette containing a Nos terminator (NosT) in front of the Cry1Ab/c gene was driven by the strong promoter ZmUbi to generate another transgenic maize LOCK. By crossing KEY and LOCK plants, the expressed Cre recombinase under the control of the Zm1rbcS promoter from KEY maize accurately removed the NosT of LOCK maize. Consequently, the expression of blocked Cry1Ab/c was enabled in specific green tissues in their hybrids. The expression level and concentration of Cry1Ab/c were observed using a strategy with high specific accumulation in green tissues (leaf and stem). Still, only a small or absent amount was observed in root and kernel tissues. Furthermore, we assessed the bioactivity of transgenic maize against 2 common lepidopteran pests, Ostrinia furnacalis and Spodoptera frugiperda, in the laboratory and field. The transgenic plants showed high plant resistance levels against the 2 pests, with mortality rates above 97.2% and damage scales below 2.2 compared with the control group. These findings are significant for exploring novel genetic engineering techniques in GM maize and providing a feasible strategy for transgenes avoiding expression in edible parts. In addition, implementing the Cre/loxP-mediated system could relieve public sentiment toward the biosafety of GM plants.

15.
ACS Appl Mater Interfaces ; 15(36): 42130-42138, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37642943

RESUMO

Poly(ß-amino ester)s (PAEs) have been widely developed for gene delivery, and hydrophobic modification can further enhance their gene transfection efficiency. However, systematic manipulation of amphiphilicity of PAEs through copolymerization with hydrophobic monomers is time-consuming and, to some extent, uncontrollable. Here, a modular strategy is developed to manipulate the amphiphilicity of the PAE/DNA polyplexes. A hydrophobic polymer (DD-C12-122) and a hydrophilic polymer (DD-90-122) are synthesized separately and used as a hydrophobic module and a hydrophilic module, respectively. The amphiphilicity of polyplexes could be manipulated by changing the ratio of the hydrophobic module and hydrophilic module. Using the modular strategy, the PAE/DNA polyplexes with the highest gene transfection efficiency and safety profile as well as possible mechanisms are identified. The modular strategy provides a novel way to engineer the hydrophobicity of PAEs to improve their gene transfection and can be easily generalized and potentially extended to other polymeric gene delivery systems.


Assuntos
DNA , Poli A , DNA/genética , Ésteres , Polímeros , Transfecção
17.
Phys Chem Chem Phys ; 25(29): 20032-20041, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37462012

RESUMO

The self-assembly behaviors of ABn miktoarm star copolymers as one typical type of asymmetric architecture have been studied well in the past few decades due to their deflected phase boundaries. In particular, recently, they have attracted renewed theoretical interest due to their expanded spherical phase region that stabilizes complex Frank-Kasper spherical phases. However, previous theoretical studies have never considered ABn copolymers with unequal arm lengths, which is more or less the case for synthesized copolymers. In this work, we investigate the self-assembly behaviors of ABn miktoarm star copolymers with unequal B-arms using self-consistent field theory. We propose an intramolecular polydispersity index (iD) to quantify the distribution of unequal B-blocks. Accordingly, we further propose a simple quantity of an effective arm number nequ = n/iD for quantitatively comparing the phase boundaries between various ABn copolymer samples with different arm numbers or different distributions of B-blocks. Our results indicate that different ABn copolymers with equal nequ exhibit similar phase diagrams. On the other hand, we also found that the phase boundaries of two different samples with same nequ are not exactly overlapped. We speculate that the effect of spontaneous curvature may be mainly controlled by nequ, but the packing frustration of B-blocks may also be dependent on the other quantities that are closely related to the shape of the distribution of B-arms, such as higher order polydispersity indexes.

18.
J Environ Manage ; 344: 118631, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459815

RESUMO

Efficient and safe removal of arsenic and lead from industrial wastewater is essential for ecological protection. In this study, we developed a novel method using lead slag as a purifying agent and sodium chloride as a reinforcing agent to remove arsenic and lead from industrial wastewater. Through a combination of experiments and simulations, we elucidated the mechanisms involved in this reaction. The initial concentrations of As and Pb ions in the industrial wastewater were 4333 and 188 mg/L, respectively. After the reaction at 25 °C and a pH ranging from 9.7 to 10, the concentrations of arsenic and lead were reduced to 4.9 mg/L and 0.008 mg/L, respectively, achieving a removal rate of 99.9%. Our experimental results demonstrated that Pb2+ and AsO43- ions released from the lead slag and industrial wastewater reacted with Cl- ions to form Pb5(AsO4)3Cl precipitates, thus effectively eliminating a significant amount of As and Pb species. Simulation studies indicated that Pb5(AsO4)3Cl exhibited exceptional stability below 400 °C and could be directly stored. Additionally, the lead slag, which is rich in silica, played a crucial role in removing and stabilizing As and Pb ions. Under alkaline conditions, silica encapsulated the As and Pb species, adhering to the surface of the Pb-As co-precipitates and forming dense, irregular, small particles with internal and external structures that impeded the efflux of As and Pb ions. This phenomenon was confirmed through scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The kinetics of As and Pb ion removal was consistent with the pseudo-second-order kinetic model, indicating that the removal process was primarily governed by chemical interactions. Lead slag exhibits significant potential and advantages in the removal of As and Pb. This innovative method offers an effective approach to address heavy metal contamination in industrial wastewater, thus contributing to ecological protection.


Assuntos
Arsênio , Metais Pesados , Poluentes Químicos da Água , Águas Residuárias , Cloretos , Chumbo , Metais Pesados/química , Dióxido de Silício , Adsorção , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
19.
Front Neuroinform ; 17: 1118419, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360945

RESUMO

Introduction: The exorbitant cost of accurately annotating the large-scale serial scanning electron microscope (SEM) images as the ground truth for training has always been a great challenge for brain map reconstruction by deep learning methods in neural connectome studies. The representation ability of the model is strongly correlated with the number of such high-quality labels. Recently, the masked autoencoder (MAE) has been shown to effectively pre-train Vision Transformers (ViT) to improve their representational capabilities. Methods: In this paper, we investigated a self-pre-training paradigm for serial SEM images with MAE to implement downstream segmentation tasks. We randomly masked voxels in three-dimensional brain image patches and trained an autoencoder to reconstruct the neuronal structures. Results and discussion: We tested different pre-training and fine-tuning configurations on three different serial SEM datasets of mouse brains, including two public ones, SNEMI3D and MitoEM-R, and one acquired in our lab. A series of masking ratios were examined and the optimal ratio for pre-training efficiency was spotted for 3D segmentation. The MAE pre-training strategy significantly outperformed the supervised learning from scratch. Our work shows that the general framework of can be a unified approach for effective learning of the representation of heterogeneous neural structural features in serial SEM images to greatly facilitate brain connectome reconstruction.

20.
BMC Cardiovasc Disord ; 23(1): 316, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355559

RESUMO

OBJECTIVES: To investigate whether ferroptosis is involved in HCY-induced endothelial injury and the possible mechanism of HCY-induced ferroptosis. METHODS: EA. hy926 cells were cultured in vitro. Cells were intervened using HCY and Fer-1. The cells were divided into Control groups, HCY (4 mM), HCY (8 mM), HCY + Fer-1 (4 mM HCY + 0.5/2.5/5 µM Fer-1). CCK-8 assay was used to detect cell viability; Flow Cytometry was used to detect cellular Lip-ROS, TBA and Microplate assay was used to detect MDA&GSH, Western blot was used to detect the expression of ferroptosis-related proteins GPX4 and SLC7A11. RESULTS: HCY can inhibited the proliferation of EA. hy926 cells in a time- and concentration-dependent manner; Fer-1 inhibits HCY-induced ferroptosis in EA.hy926 cells in a concentration-dependent manner; Compared with the control group, the cell viability and GSH content in the HCY group was significantly decreased (p < 0.05), and the Lip-ROS and MDA were significantly increased (p < 0.05); After co-culture of HCY and Fer-1, compared with the HCY (4 mM) group, the cell viability and GSH content in the co-culture group were significantly increased (p < 0.05), and the Lip-ROS and MDA were significantly decreased (p < 0.05) in a concentration-dependent manner; Western blotting results showed that the protein expression levels of ferroptosis-related proteins GPX4 and SLC7A11 in each experimental were significantly decreased after HCY treatment (p < 0.05), and Fer-1 could significantly reverse this effect. CONCLUSIONS: (1) HCY can induce ferroptosis in vascular endothelial cells. (2) HCY may induce vascular endothelial cell ferroptosis through the system Xc-GSH-GPX4 signaling pathway.


Assuntos
Células Endoteliais , Ferroptose , Homocisteína , Transdução de Sinais , Humanos , Homocisteína/toxicidade , Espécies Reativas de Oxigênio
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