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1.
Small ; 20(3): e2306806, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37688339

RESUMO

The issues of polysulfide shuttling and lethargic sulfur redox reaction (SROR) kinetics are the toughest obstacles of lithium-sulfur (Li-S) battery. Herein, integrating the merits of increased density of metal sites and synergistic catalytic effect, a unique single-atom catalyst (SAC) with nonmetallic-bonding Fe-Mn diatomic pairs anchored on hollow nitrogen-doped carbonaceous nanodisk (denoted as FeMnDA@NC) is successfully constructed and well characterized by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, etc. Density functional theory calculation indicates that the Fe-Mn diatomic pairs can effectively inhibit the shuttle effect by enhancing the adsorption ability retarding the polysulfide migration and accelerate the SROR kinetics. As a result, the Li-S battery assembled with FeMnDA@NC modified separator possesses an excellent electrochemical performance with ultrahigh specific capacities of 1419 mAh g-1 at 0.1 C and 885 mAh g-1 at 3.0 C, respectively. An outstanding specific capacity of 1165 mAh g-1 is achieved at 1.0 C and maintains at 731 mAh g-1 after 700 cycles. Notably, the assembled Li-S battery with a high sulfur loading of 5.35 mg cm-2 harvests a practical areal capacity of 5.70 mAh cm-2 at 0.2 C. A new perspective is offered here to construct advanced SACs suitable for the Li-S battery.

2.
Langmuir ; 40(17): 9028-9038, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38635954

RESUMO

Aqueous zinc-ion batteries (AZIBs) suffer from sharp cycling deterioration due to serious interfacial side reactions and corrosion problems on the zinc anode. Herein, an efficacious approach to construct hydrophobic ZnMoO4 coatings on Zn (denoted as Zn@ZMO) is proposed to mitigate direct contact between the zinc anode and electrolyte and enhance its cycle life. The hydrophobic ZnMoO4 layer (contact angle = 128°) with a honeycomb-like structure is prepared by an in situ liquid phase deposition method. The as-prepared ZnMoO4 coating exhibits persistent corrosion protection for Zn through 30 days of immersion in a 2 M ZnSO4 electrolyte, indicating excellent stability of the ZnMoO4 layer and ensuring its available application in AZIBs. Unique microchannels in this kind of honeycomb-like structured coating favor Zn2+ ion diffusion and ease of ion transport, especially at high current cycling. Its robust surface exclusion can effectively counter other side reactions induced by water, simultaneously. As a result, the Zn@ZMO symmetrical cell shows a remarkable cycle lifespan exceeding 2700 h at 1 mA cm-2/1 mA h cm-2, surpassing that of the bare zinc cell by more than 100 folds. At a current density of 5 A g-1, the Zn@ZMO//V2O5 cell can still achieve a specific capacity of 167.0 mA h g-1 after 500 cycles with a capacity retention rate of 88%, which demonstrates its long-term cycling stability.

3.
Environ Sci Technol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916160

RESUMO

The widespread ozone (O3) pollution is extremely hazardous to human health and ecosystems. Catalytic decomposition into O2 is the most promising method to eliminate ambient O3, while the fast deactivation of catalysts under humid conditions remains the primary challenge for their application. Herein, we elaborately developed a splendidly active and stable Mn-based catalyst with double hydrophobic protection of active carbon (AC) and CeO2 (CeMn@AC), which possessed abundant interfacial oxygen vacancies and excellent desorption of peroxide intermediates (O22-). Under extremely humid (RH = 90%) conditions and a high space velocity of 1200 L h-1 g-1, the optimized CeMn@AC achieved nearly 100% O3 conversion (140 h) at 5 ppm, showing unprecedented catalytic activity and moisture resistance toward O3 decomposition. In situ DRIFTS and theory calculations confirmed that the exceptional moisture resistance of CeMn@AC was ascribed to the double protection effect of AC and CeO2, which cooperatively prevented the competitive adsorption of H2O molecules and their accumulation on the active sites of MnO2. AC provided a hydrophobic reaction environment, and CeO2 further alleviated moisture deterioration of the MnO2 particles exposed on the catalyst surface via the moisture-resistant oxygen vacancies of MnO2-CeO2 crystal boundaries. This work offers a simple and efficient strategy for designing moisture-resistant materials and facilitates the practical application of the O3 decomposition catalysts in various environments.

4.
Environ Sci Technol ; 58(9): 4404-4414, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38310571

RESUMO

Photocatalytic oxidation has gained great interest in environmental remediation, but it is still limited by its low efficiency and catalytic deactivation in the degradation of aromatic VOCs. In this study, we concurrently regulated the surface hydroxyl and oxygen vacancies by introducing Al into ZnSn layered double hydroxide (LDH). The presence of distorted Al species induced local charge redistribution, leading to the remarkable formation of oxygen vacancies. These oxygen vacancies subsequently increased the amount of surface hydroxyl and elongated its bond length. The synergistic effects of surface hydroxyl and oxygen vacancies greatly enhanced reactant adsorption-activation and facilitated charge transfer to generate •OH, •O2-, and 1O2, resulting in highly efficient oxidation and ring-opening of various aromatic VOCs. Compared with commercial TiO2, the optimized ZnSnAl-50 catalyst exhibited about 2-fold activity for the toluene and styrene degradation and 10-fold activity for the chlorobenzene degradation. Moreover, ZnSnAl-50 demonstrated exceptional stability in the photocatalytic oxidation of toluene under a wide humidity range of 0-75%. This work marvelously improves the photocatalytic efficiency, stability, and adaptability through a novel strategy of surface hydroxyl and oxygen vacancies engineering.


Assuntos
Radical Hidroxila , Oxigênio , Adsorção , Oxirredução , Tolueno
5.
Environ Res ; 246: 118132, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218526

RESUMO

Arsenic (As) has been widely detected in surface media on the Qinghai-Tibetan Plateau (QTP); however, the differences in the As distribution and partitioning characteristics between freshwater and saltwater lakes remain poorly understood. To determine the distribution and partitioning characteristics of As, multimedia environmental samples were collected from a typical small watershed consisting of a river, wetland, and both freshwater and saltwater lakes on the QTP. Results showed that freshwater systems, represented by Hurleg Lake, were high in particulate arsenic (PAs) and low in dissolved arsenic (DAs), whereas the saltwater system represented by Tosen Lake, exhibited the reverse distribution. This discrepancy in As distribution was primarily attributed to evaporation enrichment, competitive adsorption of HCO3- and pH variations, as suggested by correlation analysis and stable isotopic composition of water. In the stratified Tosen Lake, an increasing trend of DAs in the water column was observed, potentially driven by the reductive dissolution of Fe (hydr)oxides and bacterial sulfate reduction in the anoxic bottom hypolimnion. Conversely, Hurleg Lake maintained oxic conditions with stable DAs concentrations. Notably, PAs was elevated in the bottom layer of both lakes, possibly due to uptake/adsorption by biogenic particles, as indicated by high levels of chl.α and suspended particulate matter. These findings offer insights into the potential future impact of climate change on As mobilization/redistribution in arid plateau lakes, with implications for management policies that regulate As pollution.


Assuntos
Arsênio , Lagos , Lagos/química , Arsênio/análise , Tibet , Monitoramento Ambiental/métodos , Água , China
6.
Angew Chem Int Ed Engl ; : e202407315, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818545

RESUMO

Li metal is regarded as the "Holy Grail" in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high-power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron-donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF-rich alloy-doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high-power dendrite-free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra-long cycle life of over 8000 h (20,000 cycles) for symmetric cells at a current density of 10 mA cm-2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra-high currents (40 C) completes the charging/discharging process in only 68 s to provide high capacity of 151 mAh g-1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite-free Li metal anode.

7.
Environ Sci Technol ; 57(46): 17727-17736, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36862670

RESUMO

Ozone (O3) pollution is highly detrimental to human health and the ecosystem due to it being ubiquitous in ambient air and industrial processes. Catalytic decomposition is the most efficient technology for O3 elimination, while the moisture-induced low stability represents the major challenge for its practical applications. Here, activated carbon (AC) supported δ-MnO2 (Mn/AC-A) was facilely synthesized via mild redox in an oxidizing atmosphere to obtain exceptional O3 decomposition capacity. The optimal 5Mn/AC-A achieved nearly 100% of O3 decomposition at a high space velocity (1200 L g-1 h-1) and remained extremely stable under entire humidity conditions. The functionalized AC provided well-designed protection sites to inhibit the accumulation of water on δ-MnO2. Density functional theory (DFT) calculations confirmed that the abundant oxygen vacancies and a low desorption energy of intermediate peroxide (O22-) can significantly boost O3 decomposition activity. Moreover, a kilo-scale 5Mn/AC-A with low cost (∼1.5 $/kg) was used for the O3 decomposition in practical applications, which could quickly decompose O3 pollution to a safety level below 100 µg m-3. This work offers a simple strategy for the development of moisture-resistant and inexpensive catalysts and greatly promotes the practical application of ambient O3 elimination.


Assuntos
Ozônio , Humanos , Óxidos , Carvão Vegetal , Umidade , Compostos de Manganês , Ecossistema , Oxigênio , Catálise
8.
Environ Sci Technol ; 57(17): 7041-7050, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37078822

RESUMO

Ozone catalytic oxidation (OZCO) has gained great interest in environmental remediation while it still faces a big challenge during the deep degradation of refractory volatile organic compounds (VOCs) at room temperature. Hydroxylation of the catalytic surface provides a new strategy for regulating the catalytic activity to boost VOC degradation. Herein, OZCO of toluene at room temperature over hydroxyl-mediated MnOx/Al2O3 catalysts was originally demonstrated. Specifically, a novel hydroxyl-mediated MnOx/Al2O3 catalyst was developed via the in situ AlOOH reconstruction method and used for toluene OZCO. The toluene degradation performance of MnOx/Al2O3 was significantly superior to those of most of the state-of-the-art catalysts, and 100% toluene was removed with an excellent mineralization rate (82.3%) and catalytic stability during OZCO. ESR and in situ DRIFTs results demonstrated that surface hydroxyl groups (HGs) greatly improved the reactive oxygen species generation, thus dramatically accelerating the benzene ring breakage and deep mineralization. Furthermore, HGs provided anchoring sites for uniformly dispersing MnOx and greatly enhanced toluene adsorption and ozone activation. This work paves a way for deep decomposition of aromatic VOCs at room temperature.


Assuntos
Ozônio , Óxidos , Temperatura , Tolueno , Oxirredução , Radical Hidroxila , Catálise
9.
Anal Bioanal Chem ; 415(27): 6723-6731, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37733257

RESUMO

In optical biosensing, analyte-independent factors such as autofluorescence interference and excitation source fluctuation decrease the sensitivity and accuracy. Herein, we reported a bimodal persistent luminescence strategy to design dual-emissive persistent luminescence nanoparticles (PLNPs) with built-in self-calibration to preclude interference from analyte-independent factors in biosensing. As a proof of concept, ZnGa2O4:Cr PLNPs with emissions at both 490 nm and 695 nm were designed. The I490/I695 ratio of ZnGa2O4:Cr was readily adjusted by simply changing the doping concentration of Cr3+. The ZnGa2O4:Cr PLNPs were employed for the ratiometric detection of urinary mesna. A good linear relationship between the I490/I695 ratio of ZnGa2O4:Cr-based nanoprobe and the concentration of mesna was obtained in the range of 0-40 µM. The limit of detection was about 0.40 µM. Results showed that autofluorescence interference from urine was totally eliminated by collecting the persistent luminescence signal of ZnGa2O4:Cr after excitation ceased. Moreover, the built-in self-calibration feature of the ratiometric ZnGa2O4:Cr PLNPs efficiently suppressed the interference from fluctuations in instrumental parameters during urinary mesna detection. The recovery rates of mesna in the spiked urine samples are in the range of 99.1~109.0%, showing the reliability of the ratiometric ZnGa2O4:Cr PLNPs in urinary mesna detection. ZnGa2O4:Cr can further be expanded to the detection of other analytes in complex matrices. This study may open new opportunities for the design of dual-emissive PLNPs with tunable ratios of emission intensity, and it can further promote the applications of optical biosensing in disease diagnosis, food safety, and environmental monitoring.

10.
Arch Biochem Biophys ; 715: 109082, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34767797

RESUMO

Pulmonary fibrosis is a severe condition with limited therapeutic options and characterized by increased fibroblast activation and progressive accumulation of extracellular matrix. Ghrelin, a gastrointestinal hormone, has been reported to possess protective roles in lung diseases including pulmonary fibrosis. However, the precise mechanisms underlying the protective effects of ghrelin remain unknown. The present study was designed to investigate the effects of ghrelin on transforming growth factor-ß1 (TGF-ß1)-induced pulmonary fibrosis in vitro and in vivo and the possible mechanism of action. It was found that ghrelin significantly attenuated TGF-ß1-induced fibrotic responses in human lung fibroblast (IMR-90) cells and bleomycin (BLM)-induced fibrotic lung tissues. Meanwhile, ghrelin decreased the expressions of miR-125a-5p and phosphorylated smad2/3 and increased protein expressions of Kruppel-like factor 13 (KLF13) in vivo and in vitro. Ghrelin-induced anti-fibrotic effects and smad2/3 downregulation in TGF-ß1-stimulated IMR-90 cells were markedly reversed by miR-125a-5p mimics and KLF13 siRNA. Furthermore, miR-125a-5p directly targeted KLF13 in IMR-90 cells. Our findings suggest that ghrelin attenuates TGF-ß1-induced pulmonary fibrosis via the miR-125a-5p/KLF13 axis, which supports ghrelin as a new therapeutic agent against pulmonary fibrosis by antagonizing the TGF-ß1 signaling pathway.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Grelina/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , MicroRNAs/metabolismo , Fibrose Pulmonar/metabolismo , Proteínas Repressoras/metabolismo , Animais , Bleomicina , Linhagem Celular , Regulação para Baixo , Humanos , Masculino , Fibrose Pulmonar/induzido quimicamente , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1
11.
Org Biomol Chem ; 19(11): 2512-2516, 2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33662088

RESUMO

A direct and straightforward thiocyanation of enamides with NH4SCN under metal-free conditions has been accomplished. A variety of (E)-ß-thiocyanoenamides are readily produced in a regio- and stereo-selective manner. The protocol features mild reaction conditions, good functional group tolerance and operational simplicity. The potential utility of this strategy was further demonstrated by transformation of thiocyanate into thiotetrazole-containing compounds and a Pd-catalyzed cross-coupling reaction to afford six- or seven-membered sulfur-containing heterocycles. Mechanistic insights into the reaction indicate that the reaction may proceed via a radical mechanism.

12.
Eur J Neurosci ; 51(2): 628-640, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31483893

RESUMO

Understanding the functional dynamics of neural oscillations in the sensory thalamus is essential for elucidating the perception and modulation of neuropathic pain. Local field potentials were recorded from the sensory thalamus of twelve neuropathic pain patients. Single and combinational neural states were defined by the activity state of a single or paired oscillations. Relationships between the duration or occurrence rate of neural state and pre-operative pain level or pain relief induced by deep brain stimulation were evaluated. Results showed that the occurrence rate of the single neural state of low-beta oscillation was significantly correlated with pain relief. The duration and occurrence rate of combinational neural states of the paired low-beta with delta, theta, alpha, high-beta or low-gamma oscillations were more significantly correlated with pain relief than the single neural states. Moreover, these significant combinational neural states formed a local oscillatory network with low-beta oscillation as a key node. The results also showed correlations between measures of combinational neural states and subjective pain level as well. The duration of combinational neural states of paired alpha with delta or theta oscillations and the occurrence rate of neural states of the paired delta with low-beta or low-gamma oscillations were significantly correlated with pre-operative pain level. In conclusion, this study revealed that the integration of oscillations and the functional dynamics of neural states were differentially involved in modulation and perception of neuropathic pain. The functional dynamics could be biomarkers for developing neural state-dependent deep brain stimulation for neuropathic pain.


Assuntos
Neuralgia , Tálamo , Humanos , Neuralgia/terapia
13.
J Cell Physiol ; 234(3): 2552-2565, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30144053

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with increasing occurrence, high death rates and unfavorable treatment regimens. In the current study, we identified the expression of microRNA-9 (miR-9) and anoctamin-1 (ANO1) in IPF mouse models induced by bleomycin, and their effects on inflammation and fibroblast proliferation through the transforming growth factor-ß (TGF-ß)-Smad3 pathway. To verify the targeting relationship between miR-9 and ANO1, we used bioinformatics prediction and conducted a dual-luciferase reporter gene assay. The underlying regulatory mechanisms of miR-9 and the target gene ANO1 were investigated mainly with the treatment of miR-9 mimic, miR-9 inhibitor, or siRNA against ANO1 in fibroblasts isolated from IPF mice. Enzyme-linked immunosorbent assay was performed to investigate the effect of miR-9 or ANO1 on inflammatory factors. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and flow cytometry were used to detect fibroblast proliferation and apoptosis. Reverse transcription quantitative polymerase chain reaction and western blot analysis were applied to measure the expression of the TGF-ß-Smad3 pathway-related genes. The determination of luciferase activity suggested that miR-9 targets ANO1. Upregulation of miR-9 or silencing of ANO1 intensified inflammation in IPF, promoted proliferation and inhibited apoptotic ability of lung fibroblasts. MiR-9 negatively modulated ANO1, and thus activated the TGF-ß-Smad3 pathway. These findings suggest that miR-9 can indirectly activate the TGF-ß-Smad3 pathway by inhibiting the expression of ANO1, thereby aggravating inflammation, promotes proliferation and suppressing apoptosis of lung fibroblasts in mice models of IPF.


Assuntos
Anoctamina-1/metabolismo , Regulação para Baixo/genética , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , MicroRNAs/genética , Animais , Apoptose/efeitos dos fármacos , Bleomicina/farmacologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Fibrose Pulmonar Idiopática/genética , Pulmão/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo
14.
J Biomater Sci Polym Ed ; 35(8): 1197-1213, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38421916

RESUMO

Rapamycin (RAP) is currently being developed as potential antibreast cancer drug. However, its poor solubility completely limits its use. The aim of this study was to develop polyethylene glycol-poly(lactide-co-glycolide) (PEG-PLGA)-based nanoparticles (NPs) to load RAP via microfluidics with an appropriate polyethylene glycol (PEG) content to enhance the bioavailability of RAP. Polydimethylsiloxane (PDMS) chips with a Y-shaped channel were designed to obtain RAP-loaded PEG-PLGA NPs (RAP-PEG-PLGA). The entrapment efficiency (EE) and drug loading (DL) as well as release profile of RAP-PEG-PLGA were evaluated, and their resistance to plasma albumin adsorption of NPs with different PEG contents was evaluated and compared. RAW264.7 and 4T1 cells were used to assess the antiphagocytic and anticancer cells effect of NPs, respectively. RAP-PEG-PLGA of around 124 nm in size were successfully prepared with the EE of 82.0% and DL of 12.3%, and sustained release for around 40 d. A PEG relative content of 10% within the PEG-PLGA molecule was shown superior in resisting protein adsorption. RAP-PEG-PLGA inhibited the growth of breast cancer cells when the concentration was over 10 µg/mL, and the inhibition efficiency was significantly higher than free RAP. Hence, the current RAP-PEG-PLGA could be a potential therapeutic system for breast cancer treatment.


Assuntos
Portadores de Fármacos , Nanopartículas , Polietilenoglicóis , Sirolimo , Sirolimo/química , Sirolimo/administração & dosagem , Sirolimo/farmacologia , Sirolimo/farmacocinética , Polietilenoglicóis/química , Animais , Nanopartículas/química , Camundongos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Linhagem Celular Tumoral , Células RAW 264.7 , Tamanho da Partícula , Precipitação Química , Adsorção , Humanos , Poliésteres
15.
J Food Sci ; 89(2): 851-865, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38174744

RESUMO

Cell-based meat technology provides an effective method to meet the demand for meat, while also posing a huge challenge to the expansion of myoblasts. It is difficult to develop serum-free medium suitable for long-term culture and large-scale expansion of myoblasts, which causes limited understanding of myoblasts expansion. Therefore, this study used C2C12 myoblasts as model cells and developed a serum-free medium for large-scale expansion of myoblasts in vitro using the Plackett-Burman design. The serum-free medium can support short-term proliferation and long-term passage of C2C12 myoblasts, while maintaining myogenic differentiation potential well, which is comparable to those of growth medium containing 10% fetal bovine serum. Based on the C2C12 myoblasts microcarriers serum-free culture system established in this study, the actual expansion folds of myoblasts can reach 43.55 folds after 7 days. Moreover, cell-based meat chunks were preliminarily prepared using glutamine transaminase and edible pigments. The research results provide reference for serum-free culture and large-scale expansion of myoblasts in vitro, laying the foundation for cell-based meat production. PRACTICAL APPLICATION: This study developed a serum-free medium suitable for long-term passage of myoblasts and established a microcarrier serum-free culture system for myoblasts, which is expected to solve the problem of serum-free culture and large-scale expansion of myoblasts in cell culture meat production.


Assuntos
Técnicas de Cultura de Células , Carne in vitro , Proliferação de Células , Técnicas de Cultura de Células/métodos , Mioblastos , Diferenciação Celular
16.
ACS Appl Mater Interfaces ; 15(32): 38644-38652, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37527437

RESUMO

Persistent luminescence nanoparticles (PLNPs) have shown special advantages in areas such as bioimaging, cancer therapy, stress sensing, and photo-biocatalysis. However, the lack of methods for controllable synthesis of PLNPs with uniform morphologies and strong persistent luminescence has seriously hindered the applications of PLNPs. Herein, we reported that modifying the electronic structures of zinc gallogermanate (ZGGO) PLNPs by nonstoichiometric reactions can produce highly uniform nanocubes with controllable size and persistent luminescence. By nonstoichiometric increase of the Ge/Ga ratio in ZGGO, the ZGGO PLNPs were transformed from a mixture of nanocubes and small nanospheres into highly symmetrical and uniform large nanocubes, accompanied by the enhancement of persistent luminescence intensity by about 3.7 times. Moreover, we found that ZGGO PLNPs were responsive to reactive oxygen species (ROS), that is, the persistent luminescence of ZGGO can be quenched by ROS. Autofluorescence-free serum ROS detection was achieved with the developed PLNPs. Further, a biosensing assay for glucose oxidase (GOx) was designed based on the responsiveness of ZGGO PLNPs to H2O2. This study may pave a new way for better control of PLNPs' size, morphology, and persistent luminescence, and it can further promote the applications of PLNPs in areas ranging from theranostics to solar energy utilization.


Assuntos
Nanopartículas , Nanosferas , Luminescência , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Nanopartículas/química
17.
Materials (Basel) ; 16(17)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37687552

RESUMO

NOx emission from the cement industry have received much attention. In order to reduce the NOx emission in cement kilns, nickel slag was used to prepare the non-ammonia denitrification material, and a denitrification mechanism was proposed in this study. The results showed that the denitrification material prepared at pH 7 exhibited the best denitrification performance. At low temperature, the highest denitrification performance was achieved between 200 and 300 °C with a NO decomposition rate of approximately 40%. Then, the NO decomposition rate increased as the temperature increased, reaching over 95% above 700 °C. The physicochemical characteristics showed that the material had the highest specific surface area and the highest relative Fe content, which benefited the denitrification performance. The divalent iron of the denitrification material was considered the active site for the reaction, and trivalent iron was not conducive to denitrification performance at a low temperature range. After the denitrification reaction, the Fe3+/Fe2+ increased from 0.89 to 1.31. The proposed denitrification mechanism was the redox process between divalent iron and trivalent iron. This study not only recycles industrial waste to reduce solid waste pollution but also efficiently removes nitrogen oxides from cement kilns without ammonia.

18.
Afr Health Sci ; 23(3): 607-615, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38357157

RESUMO

Background: To investigate the expression of Th17, T lymphocyte immunoglobulin mucin 3 (TIM-3+) cells and their related cytokines in atrial fibrillation (AF) and their clinical significance. Methodology: A total of 90 patients with AF were divided into paroxysmal group (n=45) and chronic group (n=45), and 45 healthy volunteers were selected as the control group. The proportion of Th17 cells and Tim-3 + cells in the peripheral blood were detected. The concentrations of related cytokines in peripheral blood serum were determined. The correlation between Th17 / Tim-3+ cells and related cytokines was analysed. Results: Compared with the control group, the proportion of Th17 cells and the concentration of related cytokines (IL-17, IL-6 and Matrix metalloproteinase (MMP9)) in peripheral blood of patients with paroxysmal and chronic AF increased significantly, while the proportion of tim3 + cells and the concentration of related cytokines decreased significantly. Compared with the paroxysmal group, the proportion of Th17 cells and the concentration of related cytokines in the peripheral blood of patients in the chronic group increased significantly, while the proportion of tim3 + cells and the concentration of related cytokines decreased significantly. Conclusion: Th17 / Tim-3 + cell balance is involved in AF, and can be used as a target for AF treatment.


Assuntos
Fibrilação Atrial , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Mucina-3/metabolismo , Fibrilação Atrial/etiologia , Citocinas/metabolismo , Células Th17/metabolismo , Células Th17/patologia , Imunoglobulinas/metabolismo
19.
J Neuroimmunol ; 377: 578068, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36948094

RESUMO

Neuropathic pain seriously affects people's life, but its mechanism is not clear. Interleukin-17 (IL-17) is a proinflammation cytokine and involved in pain regulation. Our previous study found that IL-17 markedly enhanced the excitatory activity of spinal dorsal neurons in mice spinal slices. The present study attempts to explore if IL-17 contributes to neuropathic pain and spinal synapse plasticity. A model of spared nerve injury (SNI) was established in C57BL/6 J mice and IL-17a mutant mice. The pain-like behaviors was tested by von Frey test and dynamic mechanical stimuli, and the expression of IL-17 and its receptor, IL-17RA, was detected by immunohistochemical staining. C-fiber evoked field potentials were recorded in vivo. In the spinal dorsal horn, IL-17 predominantly expressed in the superficial spinal astrocytes and IL-17RA expressed mostly in neurons and slightly in astrocytes. The SNI-induced static and dynamic allodynia was significantly prevented by pretreatment of neutralizing IL-17 antibody (intrathecal injection, 2 µg/10 µL) and attenuated in IL-17a mutant mice. Post-treatment of IL-17 neutralizing antibody also partially relieved the established mechanical allodynia. Moreover, spinal long-term potentiation (LTP) of C-fiber evoked field potentials, a substrate for central sensitization, was suppressed by IL-17 neutralizing antibody. Intrathecal injection of IL-17 recombinant protein (0.2 µg/10 µL) mimicked the mechanical allodynia and facilitated the spinal LTP. These data implied that IL-17 in the spinal cord played a crucial role in neuropathic pain and central sensitization.


Assuntos
Interleucina-17 , Neuralgia , Ratos , Camundongos , Animais , Hiperalgesia/metabolismo , Ratos Sprague-Dawley , Camundongos Endogâmicos C57BL , Neuralgia/metabolismo , Medula Espinal/metabolismo , Sinapses/metabolismo
20.
Sci Total Environ ; 892: 164567, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37268120

RESUMO

Atmospheric particulate matter (PM) enriched with lead (Pb) has severe irreversible effects on human health. Therefore, identifying the contribution of Pb emission sources is essential for protecting the health of residents. Using the Pb isotopic tracer method, this study explored the seasonal characteristics and primary anthropogenic Pb sources for atmospheric PM in Tianjin in 2019. We calculated the contribution of Pb sources using the end-member and MixSIAR models. The results showed that Pb loaded in PM10 was more abundant in January than in July, and was strongly influenced by meteorological conditions and anthropogenic emissions. The primary Pb sources of the aerosol samples originated from coal combustion and vehicle and steel plant emissions, mainly originating from local Pb emission sources in Tianjin. The PM10-bond Pb in January was influenced by regional transportation and local sources. The MixSIAS model calculated the contribution of coal combustion as approximately 50 %. Compared with that in January, the contribution of coal combustion decreased by 9.6 % in July. Our results indicate that some of the benefits of phased-out leaded gasoline have been short-lived, whereas other industrial activities releasing Pb have increased. Furthermore, the results emphasise the practicability of the Pb isotope tracer source approach for identifying and distinguishing between different anthropogenic Pb inputs. Based on this study, scientific and effective air pollution prevention and control programs can be formulated to provide decision support for the guidance and control of air pollutant emissions.


Assuntos
Poluentes Atmosféricos , Chumbo , Humanos , Chumbo/análise , Teorema de Bayes , Material Particulado/análise , Poluentes Atmosféricos/análise , Isótopos/análise , Carvão Mineral/análise , Monitoramento Ambiental/métodos , China
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