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1.
ACS Appl Mater Interfaces ; 16(15): 18833-18842, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38574180

RESUMO

Sodium-ion batteries (SIBs) offer several benefits, including cost-efficiency and fast-charging characteristics, positioning them as attractive substitutes for lithium-ion batteries in energy storage applications. However, the inferior capacity and cycling stability of electrodes in SIBs necessitate further enhancement due to sluggish reaction kinetics. In this respect, the utilization of heterostructures, which can provide an inherent electric field and abundant active sites on the surface, has emerged as a promising strategy for augmenting the cycling stability and rate features of the electrodes. This work delves into the utilization of V1.13Se2/V2O3 heterostructure materials as anodes, initially fabricated via a simplified one-step solid-state sintering technique. The high pseudocapacitance and low characteristic relaxation time constant give the V1.13Se2/V2O3 heterostructure impressive properties, such as a high capacity of 328.5 mAh g-1 even after 1500 cycles at a high current density of 2 A g-1 and rate capability of 278.9 mAh g-1 at 5 A g-1. Moreover, the assembled sodium-ion full battery delivers a capacity of 118.5 mAh g-1 after 1000 cycles at 1 A g-1. These findings provide novel insight and guidance for the rapid synthesis of heterojunction materials and the advancement of SIBs.

2.
Front Surg ; 11: 1363551, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550792

RESUMO

Background: This study aimed to evaluate the reference value of the femoral anterior tangent (FAT) line as a guidance of distal femoral rotation on magnetic resonance images (MRI). Methods: We retrospectively included 81 patients (106 knees) diagnosed as ailing from primary knee osteoarthritis. The indirect rotational axes including the FAT line, the perpendicular line to the anteroposterior axis (pAPA), and the posterior condylar axis (PCA) were identified on MRI, and their angles related to the clinical transepicondylar axis (cTEA) or surgical transepicondylar axis (sTEA) were measured. The patients were further divided into subgroups according to the Kellgren-Lawrence (K-L) grades, the joint-line convergence angle (JLCA), and the arithmetic hip-knee-ankle angle (aHKA) to assess the variance of different rotational reference axes. Results: The FAT line was -11.8° ± 3.6° internally rotated to the cTEA and -7.5° ± 3.6° internally rotated to the sTEA. The FAT/cTEA angle and the FAT/sTEA angle shared a similar frequency distribution pattern but a little greater variance to the pAPA/cTEA angle and the PCA/cTEA angle. The PCA/cTEA angle in the JLCA |x| ≥ 6° subgroup was significantly smaller than in the two other JLCA subgroups. The pAPA/cTEA angle and the PCA/cTEA angle also presented statistical significance within the aHKA subgroups. While the FAT/cTEA angle and the FAT/sTEA angle demonstrated superior stability among the different K-L grades, JLCA subgroups, and aHKA subgroups. Conclusion: The FAT line was less affected by the degree of knee osteoarthritis and lower limb alignment, which could serve as a reliable alternative reference axis for the distal femoral rotational alignment in total knee arthroplasty.

3.
PLoS One ; 19(2): e0298442, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38329956

RESUMO

BACKGROUND: Helicobacter pylori infections are generally acquired during childhood and affect half of the global population, but its transmission route remains unclear. It is reported that H. pylori can be internalized into Candida, but more evidence is needed for the internalization of H. pylori in human gastrointestinal Candida and vaginal Candida. METHODS: Candida was isolated from vaginal discharge and gastric mucosa biopsies. We PCR-amplified and sequenced H. pylori-specific genes from Candida genomic DNA. Using optical and immunofluorescence microscopy, we identified and observed bacteria-like bodies (BLBs) in Candida isolates and subcultures. Intracellular H. pylori antigen were detected by immunofluorescence using Fluorescein isothiocyanate (FITC)-labeled anti-H. pylori IgG antibodies. Urease activity in H. pylori internalized by Candida was detected by inoculating with urea-based Sabouraud dextrose agar, which changed the agar color from yellow to pink, indicating urease activity. RESULTS: A total of 59 vaginal Candida and two gastric Candida strains were isolated from vaginal discharge and gastric mucosa. Twenty-three isolates were positive for H. pylori 16S rDNA, 12 were positive for cagA and 21 were positive for ureA. The BLBs could be observed in Candida cells, which were positive for H. pylori 16S rDNA, and were viable determined by the LIVE/DEAD BacLight Bacterial Viability kit. Fluorescein isothiocyanate (FITC)-conjugated antibodies could be reacted specifically with H. pylori antigen inside Candida cells by immunofluorescence. Finally, H. pylori-positive Candida remained positive for H. pylori 16S rDNA even after ten subcultures. Urease activity of H. pylori internalized by Candida was positive. CONCLUSION: In the form of BLBs, H. pylori can internalize into gastric Candida and even vaginal Candida, which might have great significance in its transmission and pathogenicity.


Assuntos
Candidíase Vulvovaginal , Infecções por Helicobacter , Helicobacter pylori , Descarga Vaginal , Feminino , Humanos , Urease/genética , Infecções por Helicobacter/microbiologia , Fluoresceína-5-Isotiocianato , Ágar , Antígenos de Bactérias/genética , Mucosa Gástrica/microbiologia , Candida/genética , Biópsia , DNA Ribossômico , Ureia , Proteínas de Bactérias/genética
4.
Eur J Cardiothorac Surg ; 65(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38218720

RESUMO

OBJECTIVES: This study aimed to analyse and determine the role of aortic length and curvature in the pathogenesis of acute type A aortic dissection (ATAAD) with ascending aortic diameters (AADs) <5 cm. METHODS: We reviewed the clinical and imaging data of patients with ATAAD (n = 201) and ascending aortic dilation (n = 83). Thoracic aortic bending index (TABI) was used to quantify aortic curvature and analyse its role in ATAAD below the diameter risk threshold. RESULTS: The AAD was <5.0 and <4.0 cm in 78% and 37% of patients with ATAAD, respectively. The median ascending aortic length (AAL) was 104.6 mm (Q1-Q3, 96.5-113.6 mm), and in 62.7% of patients, it was <11 cm. The median TABI was 14.99 mm/cm (Q1-Q3, 14.18-15.86 mm/cm). Patients with ATAAD and those with aortic dilation were matched for AAD, age, sex, height and other clinical factors. After matched, the dissection group had higher AALs (median, 102.9 mm; Q1-Q3, 96.0-112.5 mm vs median, 88.2 mm; Q1-Q3, 83.7-95.9 mm; P < 0.001) and TABI (median, 14.84 mm/cm; Q1-Q3, 14.06-15.83 mm/cm vs median, 13.55 mm/cm; Q1-Q3, 13.03-14.28 mm/cm; P < 0.001). According to the regression analysis, the area under the curve required to distinguish patients with ATAAD from those with aortic dilation was 0.831 in AAL, 0.837 in TABI and 0.907 when AAL was combined with TABI. CONCLUSIONS: The patients with ATAAD had higher AAL and TABI than those with aortic dilation. The combination of TABI and AAL might be a potential morphological marker for determining ATAAD risk below the current aortic diameter risk threshold.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Humanos , Estudos Retrospectivos , Dissecção Aórtica/diagnóstico por imagem , Aorta/cirurgia , Aorta Torácica/diagnóstico por imagem , Tórax , Aneurisma da Aorta Torácica/patologia
5.
J Colloid Interface Sci ; 657: 931-941, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38096776

RESUMO

Zinc-ion batteries (ZIBs) are rapidly emerging as safe, cost-effective, nontoxic, and environmentally friendly energy storage systems. However, mildly acidic electrolytes with depleted protons cannot satisfy the huge demand for proton reactions in MnO2 electrodes and also cause several issues in ZIBs, such as rapidly decaying cycling stability and low reaction kinetics. Herein, we propose a pH-buffering strategy in which KH2PO4 is added to the electrolyte to overcome the problems caused by low proton concentrations. This strategy significantly improves the rate and cycle stability performance of zinc-manganese batteries, delivering a high capacity of 122.5 mAh/g at a high current density of 5 A/g and enabling 9000 cycles at this current density, with a remaining capacity of 70 mAh/g. Ex-situ X-ray diffraction and scanning electron microscopy analyses confirmed the generation/dissolution of Zn3PO4·4H2O and Zn4(OH)6(SO4)·5H2O, byproducts of buffer products and proton reactions. In-situ pH measurements and chemical titration revealed that the pH change during the electrochemical process can be adjusted to a low range of 2.2-2.8, and the phosphate distribution varies with the pH range. Those results reveal that H2PO4- provides protons to the cathode through the chemical balance of HPO42-, HPO42-, and Zn3PO4·4H2O. This study serves as a guide for studying the influences and mechanisms of buffering additives in Zn-MnO2 batteries.

6.
Yeast ; 40(9): 401-413, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37565669

RESUMO

Helicobacter pylori are transmissible from person to person and among family members. Mother-to-child transmission is the main intrafamilial route of H. pylori transmission. However, how it transmits from mother to child is still being determined. Vaginal yeast often transmits to neonates during delivery. Therefore, H. pylori hosted in yeast might follow the same transmission route. This study aimed to detect intracellular H. pylori in vaginal and fecal yeasts isolates and explore the role of yeast in H. pylori transmission. Yeast was isolated from the mothers' vaginal discharge and neonates' feces and identified by internal transcribed spacer (ITS) sequencing. H. pylori 16S rRNA and antigen were detected in yeast isolates by polymerase chain reaction and direct immunofluorescence assay. Genetic relationships of Candida strains isolated from seven mothers and their corresponding neonates were determined by random amplified polymorphic DNA (RAPD) fingerprinting and ITS alignment. The Candida isolates from four mother-neonate pairs had identical RAPD patterns and highly homologous ITS sequences. The current study showed H. pylori could be sheltered within yeast colonizing the vagina, and fecal yeast from neonates is genetically related to the vaginal yeast from their mothers. Thus, vaginal yeast presents a potential reservoir of H. pylori and plays a vital role in the transmission from mother to neonate.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Recém-Nascido , Humanos , Feminino , Mães , Helicobacter pylori/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Transmissão Vertical de Doenças Infecciosas , Saccharomyces cerevisiae/genética , RNA Ribossômico 16S/genética , Infecções por Helicobacter/diagnóstico , Candida/genética , Fezes
7.
Phys Chem Chem Phys ; 25(29): 19446-19452, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37403714

RESUMO

The 2LiF-BeF2 (FLiBe) salt melt is considered the primary choice for a coolant and fuel carrier for the generation IV molten salt reactor (MSR). However, the basics of ionic coordination and short-range ordered structures have been rarely reported due to the toxicity and volatility of beryllium fluorides, as well as the lack of suitable high-temperature in situ probe methods. In this work, the local structure of FLiBe melts was investigated in detail using the newly designed HT-NMR method. It was found that the local structure was comprised of a series of tetrahedral coordinated ionic clusters (e.g., BeF42-, Be2F73-, Be3F104-, and polymeric intermediate-range units). Li+ ions were coordinated by BeF42- ions and the polymeric Be-F network through the analysis of the NMR chemical shifts. Using solid-state NMR, the structure of solid FLiBe solidified mixed salts was confirmed to form a 3D network structure, significantly similar to those of silicates. The above results provide new insights into the local structure of FLiBe salts, which verifies the strong covalent interactions of Be-F coordination and the specific structural transformation to the polymeric ions above 25% BeF2 concentration.

8.
Bioeng Transl Med ; 8(3): e10460, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37206232

RESUMO

Retinal ischemia-reperfusion (RIR) injury is involved in the pathogenesis of various vision-threatening diseases. The overproduction of reactive oxygen species (ROS) is thought to be the main cause of RIR injury. A variety of natural products, including quercetin (Que), exhibit potent antioxidant activity. However, the lack of an efficient delivery system for hydrophobic Que and the presence of various intraocular barriers limit the effective retinal delivery of Que in clinical settings. In this study, we encapsulated Que into ROS-responsive mitochondria-targeted liposomes (abbreviated to Que@TPP-ROS-Lips) to achieve the sustained delivery of Que to the retina. The intracellular uptake, lysosome escape ability, and mitochondria targeting ability of Que@TPP-ROS-Lips were evaluated in R28 retinal cells. Treating R28 cells with Que@TPP-ROS-Lips significantly ameliorated the decrease in ATP content, ROS generation, and increase in the release of lactate dehydrogenase in an in vitro oxygen-glucose deprivation (OGD) model of retinal ischemia. In a rat model, the intravitreal injection of Que@TPP-ROS-Lips 24 h after inducing retinal ischemia significantly enhanced retinal electrophysiological recovery and reduced neuroinflammation, oxidative stress, and apoptosis. Que@TPP-ROS-Lips were taken up by retina for at least 14 days after intravitreal administration. Molecular docking and functional biological experiments revealed that Que targets FOXO3A to inhibit oxidative stress and inflammation. Que@TPP-ROS-Lips also partially inhibited the p38 MAPK signaling pathway, which contributes to oxidative stress and inflammation. In conclusion, our new platform for ROS-responsive and mitochondria-targeted drug release shows promise for the treatment of RIR injury and promotes the clinical application of hydrophobic natural products.

9.
Sci Total Environ ; 888: 164167, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37201852

RESUMO

Carbon nitride (C3N4) nanosheets have excellent adsorption capacity, environmental friendliness, and high stability for heavy metal removal. However, its application in Cd-polluted soil is difficult as aggregation induces the specific surface area to substantially decrease. In this study, a series of C3N4 nanosheet-modified porous carbons (C3N4/PC-X) were prepared by a simple one-step calcination of mixed aerogels with different mass ratios (X) of carboxymethyl cellulose (CMC) and melamine. These were based on the confined effect of the CMC aerogel, whose 3D confined region controls the C3N4 morphology and prevents the aggregation of nanosheets. The resulting C3N4/PC-4 exhibited a porous structure with interpenetrating C3N4 nanosheets and carbon rods. C3N4/PC-4 was characterized by SEM, elemental analysis, XRD, FTIR and XPS, and the existence of C3N4 nanosheets was confirmed. Compared with that of unmodified porous carbons, the adsorption capacity of C3N4/PC-4 for Cd ions increased 3.97 times, up to 273.1 mg/g. The adsorption kinetics and adsorption isotherm analyses showed that the adsorption properties were in agreement with the quasi-second-order and Freundlich adsorption models. Moreover, the material had a good passivation effect on the Cd ions in the soil. The confined synthesis of aerogels could be extended to the preparation of other nanostructures.

10.
J Magn Reson ; 350: 107426, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37011464

RESUMO

In this work, the distribution and dynamics of Li+ ions in ß-CD-PEO/Li+ (ß-CD, ß-cyclodextrin; PEO, polyethylene-oxides) crystalline polymer electrolytes were investigated by solid-state NMR to enlighten the ionic conduction mechanism. Specifically, 7Li-6Li REDOR NMR and variable-contact-time 1H-6Li CP/MAS NMR were adopted for the study. The results demonstrate that Li+ ions coordinated by polymer chains have relatively compact spatial density and fast dynamics, which facilitate the improvement of the electrochemical properties. Additionally, the variation of the distribution and dynamics of the Li+ ions and the ionic conduction mechanism were studied and discussed by altering the amount of the Li+ ions. This work deepens our understanding of the distribution and dynamics of Li+ ions in ß-CD-PEO/Li+ crystals and demonstrates possible future applications of solid-state NMR on the study of the polymer electrolytes.

11.
Exp Astron (Dordr) ; 55(2): 343-371, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063519

RESUMO

POLAR-2 is a space-borne polarimeter, built to investigate the polarization of Gamma-Ray Bursts and help elucidate their mechanisms. The instrument is targeted for launch in 2024 or 2025 aboard the China Space Station and is being developed by a collaboration between institutes from Switzerland, Germany, Poland and China. The instrument will orbit at altitudes between 340km and 450km with an inclination of 42 ∘ and will be subjected to background radiation from cosmic rays and solar events. It is therefore pertinent to better understand the performance of sensitive devices under space-like conditions. In this paper we focus on the radiation damage of the silicon photomultiplier arrays S13361-6075NE-04 and S14161-6050HS-04 from Hamamatsu. The S13361 are irradiated with 58MeV protons at several doses up to 4.96Gy, whereas the newer series S14161 are irradiated at doses of 0.254Gy and 2.31Gy. Their respective performance degradation due to radiation damage are discussed. The equivalent exposure time in space for silicon photomultipliers inside POLAR-2 with a dose of 4.96Gy is 62.9years (or 1.78years when disregarding the shielding from the instrument). Primary characteristics of the I-V curves are an increase in the dark current and dark counts, mostly through cross-talk events. Annealing processes at 25 ∘ C were observed but not studied in further detail. Biasing channels while being irradiated have not resulted in any significant impact. Activation analyses showed a dominant contribution of ß + particles around 511 keV. These resulted primarily from copper and carbon, mostly with decay times shorter than the orbital period.

12.
Part Fibre Toxicol ; 20(1): 8, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899356

RESUMO

BACKGROUND: Montmorillonite (Mt) and its derivatives are now widely used in industrial and biomedical fields. Therefore, safety assessments of these materials are critical to protect human health after exposure; however, studies on the ocular toxicity of Mt are lacking. In particular, varying physicochemical characteristics of Mt may greatly alter their toxicological potential. To explore the effects of such characteristics on the eyes, five types of Mt were investigated in vitro and in vivo for the first time, and their underlying mechanisms studied. RESULTS: The different types of Mt caused cytotoxicity in human HCEC-B4G12 corneal cells based on analyses of ATP content, lactate dehydrogenase (LDH) leakage, cell morphology, and the distribution of Mt in cells. Among the five Mt types, Na-Mt exhibited the highest cytotoxicity. Notably, Na-Mt and chitosan-modified acidic Na-Mt (C-H-Na-Mt) induced ocular toxicity in vivo, as demonstrated by increases corneal injury area and the number of apoptotic cells. Na-Mt and C-H-Na-Mt also induced reactive oxygen species (ROS) generation in vitro and in vivo, as indicated by 2',7'-dichlorofluorescin diacetate and dihydroethidium staining. In addition, Na-Mt activated the mitogen-activated protein kinase signaling pathway. The pretreatment of HCEC-B4G12 cells with N-acetylcysteine, an ROS scavenger, attenuated the Na-Mt-induced cytotoxicity and suppressed p38 activation, while inhibiting p38 activation with a p38-specific inhibitor decreased Na-Mt-induced cytotoxicity. CONCLUSIONS: The results indicate that Mt induces corneal toxicity in vitro and in vivo. The physicochemical properties of Mt greatly affect its toxicological potential. Furthermore, ROS generation and p38 activation contribute at least in part to Na-Mt-induced toxicity.


Assuntos
Bentonita , Neuropatia Óptica Tóxica , Humanos , Espécies Reativas de Oxigênio/metabolismo , Bentonita/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologia , Apoptose
13.
Front Cardiovasc Med ; 9: 927105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795370

RESUMO

Background: Type A aortic dissection (TAAD) has a rapid onset and high mortality. Currently, aortic diameter is the major criterion for evaluating the risk of TAAD. We attempted to find other aortic morphological indicators to further analyze their relationships with the risk of type A dissection. Methods: We included the imaging and clinical data of 112 patients. The patients were divided into three groups, of which Group 1 had 49 patients with normal aortic diameter, Group 2 had 22 patients with ascending aortic aneurysm, and Group 3 had 41 patients with TAAD. We used AW Server software, version 3.2, to measure aorta-related morphological indicators. Results: First, in Group 1, the univariate analysis results showed that ascending aortic diameter was correlated with patient age (r 2 = 0.35) and ascending aortic length (AAL) (r 2 = 0.43). AAL was correlated with age (r 2 = 0.12) and height (r 2 = 0.11). Further analysis of the aortic morphological indicators among the three groups found that the median aortic diameter was 36.20 mm in Group 1 (Q1-Q3: 33.40-37.70 mm), 42.5 mm in Group 2 (Q1-Q3: 41.52-44.17 mm) and 48.6 mm in Group 3 (Q1-Q3: 42.4-55.3 mm). There was no significant difference between Groups 2 and 3 (P > 0.05). Group 3 had the longest AAL (median: 109.4 mm, Q1-Q3: 118.3-105.3 mm), followed by Group 2 (median: 91.0 mm, Q1-Q3: 95.97-84.12 mm) and Group 1 (81.20 mm, Q1-Q3: 76.90-86.20 mm), and there were statistically significant differences among the three groups (P < 0.05). The Aortic Bending Index (ABI) was 14.95 mm/cm in Group 3 (Q1-Q3: 14.42-15.78 mm/cm), 13.80 mm/cm in Group 2 (Q1-Q3: 13.42-14.42 mm/cm), and 13.29 mm/cm in Group 1 (Q1-Q3: 12.71-13.78 mm/cm), and the difference was statistically significant in comparisons between any two groups (P < 0.05). Regression analysis showed that aortic diameter + AAL + ABI differentiated Group 2 and Group 3 with statistical significance (area under the curve (AUC) = 0.834), which was better than aortic diameter alone (AUC = 0.657; P < 0.05). Conclusions: We introduced the new concept of ABI, which has certain clinical significance in distinguishing patients with aortic dissection and aneurysm. Perhaps the ascending aortic diameter combined with AAL and ABI could be helpful in predicting the occurrence of TAAD.

14.
RSC Adv ; 12(20): 12600-12606, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35480363

RESUMO

Zinc finger antiviral proteins (ZAP) can significantly inhibit the replication of avian leukosis virus subgroup J (ALV-J), but the traditional method of ZAP administration is by injection, which can easily cause stress effects in chickens. In this work, we established a sodium alginate/atractylodis macrocephalae system for the encapsulation of CCCH-type zinc finger antiviral protein (CCCH-ZAP). Because of the high cost of ZAP, we first chose bovine serum albumin (BSA) as a model protein to investigate the encapsulation performance. The SEM images clearly confirmed that BSA and the sodium alginate/atractylodis macrocephalae system can assemble easily to form relatively stable nanostructures, and the encapsulation amount of BSA can reach 68%. Subsequently, the encapsulation of ZAP was studied. The SEM and the encapsulation experiments confirmed that ZAP can also be assembly encapsulated in the sodium alginate/atractylodis macrocephalae system with the encapsulation amount of 80%. Release studies showed that the SA/AM-ZAP nanocomposite was able to achieve a release rate of 32% of ZAP. This work successfully confirms the assembly encapsulation of ZAP, which will be beneficial for the usage of ZAP-based animal drugs.

15.
Inorg Chem ; 60(15): 11081-11089, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34242020

RESUMO

A CuI-TbIII heterometallic MOF, namely 1·DMF, was obtained via a coordination assembly process of isonicotinic acid with CuI and TbIII. 1·DMF can be switched to 1·MeOH in methanol with a luminescent emission response. Meanwhile, 1·MeOH exhibits a reversible single-crystal transformation to 1·DMF after immersion in DMF. Both MOFs have superior physicochemical stability. The 1·DMF-based biosensor has a remarkable sensing performance toward penicillin.


Assuntos
Cobre/química , Luminescência , Compostos Organometálicos/química , Penicilinas/análise , Térbio/química , Teoria da Densidade Funcional , Modelos Moleculares , Conformação Molecular , Penicilinas/química
16.
Environ Sci Pollut Res Int ; 28(24): 32035-32045, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33624239

RESUMO

In this paper, three-dimensional magnetic nitrogen-doped porous carbon modified by EDTA (N-MPC-EDTA) was successfully prepared by two-step method with lignin as the precursor, and was used for the removal of Cd (II). The 3D adsorbents were characterized by SEM, TEM, BET, XRD, XPS, Zeta potential, and element mapping analysis techniques, and the performance of the materials was tested by the batch adsorption method. The influence of experimental parameters such as contact time and pH value on the adsorption capacity of N-MPC-EDTA on Cd (II) was studied. Under the optimal conditions, the equilibrium adsorption capacity of Cd (II) was 43.68 mg∙ L-1 and the adsorption equilibrium was quickly reached within 45 min. A possible adsorption mechanism was proposed, in which the chelation of EDTA as well as the electrostatic attraction of hydroxyl, carboxyl, and nitrogen-containing functional groups dominated the adsorption of Cd (II). The adsorption kinetics and isotherm data fitted well with the pseudo-second-order kinetic model and Freundlich model, respectively. In addition, the good regeneration performance suggested that N-MPC-EDTA will have a broad application prospect in water treatment.


Assuntos
Cádmio , Poluentes Químicos da Água , Adsorção , Carbono , Ácido Edético , Cinética , Fenômenos Magnéticos , Nitrogênio , Porosidade , Poluentes Químicos da Água/análise
17.
Environ Sci Pollut Res Int ; 28(5): 5149-5157, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32959320

RESUMO

Carbon aerogels are attracting much attention as adsorbents due to their high specific surface and large accessible pores. Herein, we describe a successful synthesis of a magnetic carbon aerogel (MCA) using sodium alginate (SA) as the main carbon source, gelatin (G) as a cross-linking agent and secondary carbon source, and Fe3O4 nanoparticles as the magnetic component. A simple pyrolysis treatment at 550 °C under N2 transformed a Fe3O4/SA/G hydrogel precursor into the MCA. The obtained magnetic carbon aerogel possessed a high specific surface area (145.7 m2/g), a hierarchically porous structure, and an abundance of surface hydroxyl (-OH) and carboxyl (-COOH) groups, resulting in outstanding sorption properties for aqueous Cd(II) (an adsorption capacity of 143.88 mg/Lmg/g). The mechanism of Cd(II) adsorption by the MCA was investigated, with the results obtained suggesting that the MCA removed cadmium ions from water by both electrostatic adsorption and complexation. Since the MCAs contained Fe3O4 nanoparticles, they could easily be separated and recovered from water using a magnet. This study thus identifies a promising and efficient technology for removing Cd(II) ions from aqueous solutions.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Cádmio , Carbono , Íons , Fenômenos Magnéticos , Água , Poluentes Químicos da Água/análise
18.
ACS Appl Mater Interfaces ; 12(49): 54711-54719, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33216522

RESUMO

Magnesium ion batteries (MIBs) have attracted a lot of attention because of the natural abundance of magnesium, high volumetric energy density, and superior safety. Nevertheless, MIBs are still in their infancy because of the significant challenge in developing a suitable electrolyte with low flammability, high ionic conductivity, and compatibility with the Mg anode. Herein, we construct rechargeable quasi-solid-state MIBs based on tailored polymer electrolytes. The quasi-solid state electrolyte of poly(vinylidene fluoride-co-hexafluoropropylene)-nanosized SiO2-Mg(TFSI)2 combines the outstanding dynamic property of a liquid electrolyte and the good stability of a solid-state electrolyte. It exhibits a highly reversible Mg2+ deposition-dissolution capability, high ion conductivity (0.83 mS cm-1), and superior compatibility with the Mg metal and cathode. The quasi-solid-state MIBs with a layered titanic oxide cathode show a high reversible capacity of 129 mA h g-1 at 50 mA g-1 (150 W h kg-1) without any decay after 100 cycles.

19.
Sci Total Environ ; 739: 139896, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32534313

RESUMO

A novel iron nanoparticles encapsulated within nitrogen and sulfur co-doped magnetic porous carbon (Fe-N-S-MPC) was proposed by one-pot pyrolysis strategy to activate peroxymonosulfate (PMS) to degrade 1-naphthol using low-cost lignin as precursors. The Fe-N-S-MPC was characterized for structure and properties by different characterizations. The obtained materials had the morphology of iron nanoparticles encapsulated within nitrogen and sulfur co-doped magnetic porous carbon with rich functional groups and large specific surface area, which made the materials have a good catalytic property. It was proved that the doping of nitrogen and sulfur is pivotal for improving the catalytic performance. The radical quenching experiment confirmed that sulfate radical (SO4-) and hydroxyl radical (OH) are two major reactive oxygen groups. The reaction had phenomenon of the free radicals upsurge in the early stage and the shortage in the later stage. Therefore, a mathematical model was put forward to represent the two-stage reaction kinetics. By adding oxidants in batches, the degradation effect could reach nearly 100% within 30 min. The Fe-N-S-MPC were applied to the degradation of 1-naphthol in soil and showed high degradation performance. This work provided a new type of catalytic material by the high-value utilization of waste for the degradation of organic pollutants.

20.
Inflammation ; 43(3): 796-809, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31900828

RESUMO

Intervertebral disc degeneration (IDD) is characterized by an imbalance between matrix synthesis and degradation in intervertebral discs. However, the causes of this imbalance remain elusive. Previous studies revealed that NLRP3 inflammasome plays a vital role in IDD and nicotinamide phosphoribosyl transferase (NAMPT) is involved in matrix degradation induced by IL-1ß. In the current study, real-time PCR, western blot and NAMPT knockdown, or overexpression experiments were used to detect the regulatory effects of NAMPT on NLRP3 inflammasome activity in nucleus pulposus (NP) cells. The results revealed that NAMPT downregulation or overexpression controlled the matrix degradation induced by TNF-α by modulating NLRP3 inflammasome activity. Moreover, the NAMPT inhibition study demonstrated MAPK and NF-κB signaling play a key role in above process. In addition, melatonin was reported to play a protective role in matrix metabolism of NP cells. Herein, real-time PCR, western blot analysis, and immunofluorescence staining experiments revealed that melatonin showed protective effects against TNF-α-induced matrix degradation by downregulating NAMPT and reducing NLRP3 inflammasome activity in NP cells. The current investigation verified that melatonin could alleviate matrix degradation induced by TNF-α by suppressing NAMPT and NLRP3 inflammasome activity. Moreover, NAMPT downregulation controlled the matrix degradation induced by TNF-α by suppressing NLRP3 inflammasome activity through MAPK and NF-κB signaling in NP cells.


Assuntos
Citocinas/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/fisiologia , Melatonina/farmacologia , NF-kappa B/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Núcleo Pulposo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Células Cultivadas , Citocinas/metabolismo , Humanos , Inflamassomos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Núcleo Pulposo/citologia , Núcleo Pulposo/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/toxicidade
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