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1.
Nano Lett ; 24(20): 6002-6009, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38739273

RESUMEN

Two-dimensional van der Waals heterostructures (2D-vdWHs) based on transition metal dichalcogenides (TMDs) provide unparalleled control over electronic properties. However, the interlayer coupling is challenged by the interfacial misalignment and defects, which hinders a comprehensive understanding of the intertwined electronic orders, especially superconductivity and charge density wave (CDW). Here, by using pressure to regulate the interlayer coupling of non-centrosymmetric 6R-TaS2 vdWHs, we observe an unprecedented phase diagram in TMDs. This phase diagram encompasses successive suppression of the original CDW states from alternating H-layer and T-layer configurations, the emergence and disappearance of a new CDW-like state, and a double superconducting dome induced by different interlayer coupling effects. These results not only illuminate the crucial role of interlayer coupling in shaping the complex phase diagram of TMD systems but also pave a new avenue for the creation of a novel family of bulk heterostructures with customized 2D properties.

2.
Environ Pollut ; 351: 124049, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38692386

RESUMEN

To explore the impact of different functional groups on Hg(II) adsorption, a range of poly(pyrrole methane)s functionalized by -Cl, -CN, -NH2, -OH and -COOH were synthesized and applied to reveal the interaction between different functional groups and mercury ions in water, and the adsorption mechanism was revealed through combined FT-IR, XPS, and DFT calculations. The adsorption performance can be improved to varying degrees by the incorporation of functional groups. Among them, the oxygen-containing functional groups (-OH and -COOH) exhibit stronger affinity for Hg(II) and can increase the adsorption capacity from 180 mg g-1 to more than 1400 mg g-1 at 318 K, with distribution coefficient (Kd) exceeding 105 mL g-1. The variations in the capture and immobilization capabilities of functionalized poly(pyrrole methane)s predominantly stem from the unique interactions between their functional groups and mercury ions. In particular, oxygen-containing -OH and -COOH effectively capture Hg(OH)2 through hydrogen bonding, and further deprotonate to form the -O-Hg-OH and -COO-Hg-OH complexes which are more stable than those obtained from other functionalized groups. Finally, the ecological safety has been fully demonstrated through bactericidal and bacteriostatic experiments to prove the functionalized poly(pyrrole methane)s can be as an environmentally friendly adsorbent for purifying contaminated water.

3.
ACS Omega ; 9(14): 16411-16419, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38617667

RESUMEN

The enrichment of organic matter is the foundation for a high-quality shale deposition. It is generally believed that high productivity and persistent anoxic conditions facilitate the preservation and enrichment of organic matter. However, there is a lack of investigation into how the dynamic combination of productivity and anoxia affects organic matter enrichment. Here, the black shales of the Wufeng Formation and Longmaxi Formation in the western Chongqing area were selected, where oceanic anoxia and high productivity evolved as a function of the water depth. The main findings were as follows: (1) the distribution of high-quality shales in the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation is closely related to the oxygen minimum zone (OMZ), indicating that the physicochemical conditions within the OMZ zone facilitated the development of high-quality shale; (2) in the late period of the Wufeng Formation, intense ocean upwelling in the middle shelf and outer shelf regions caused high productivity where thick-bedded high-quality shales were deposited; and (3) in the early period of the Longmaxi Formation, ocean upwelling weakened, accompanied by the expansion of the OMZ to shallow water regions, and high-quality shales were widely distributed. Based on the above findings, two depositional models were proposed to account for the formation of high-quality shales, and it is suggested that intense ocean upwelling during the late period of the Wufeng Formation and OMZ expansion during the early period of the Longmaxi Formation played crucial roles in facilitating the formation of high-quality shales. These two models present the spatial and temporal variability of high-quality shale development for the first time and can guide shale gas exploration and development strategies.

4.
J Neurointerv Surg ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38580442

RESUMEN

BACKGROUND: Studies reporting spontaneous delayed migration or shortening (SDMS) after treatment with the Pipeline Embolization Device (PED) are limited. This study aimed to evaluate the incidence of SDMS after PED treatment, propose management strategies, and identify the risk factors contributing to its occurrence. METHODS: We retrospectively reviewed consecutive patients with an intracranial aneurysm (IA) treated with PEDs at three institutions. SDMS was classified as type I or II based on whether the PED covered the aneurysm neck. RESULTS: The total cohort comprised 790 patients. SDMS was identified in 24 (3.04%) patients. Eighteen of the 24 patients had type I SDMS and did not require retreatment, while the remaining six patients had type II SDMS and all received retreatment. Multivariate logistic regression showed that the difference between the proximal and distal parent artery diameters (DPAD) (adjusted OR 2.977; 95% CI 1.054 to 8.405; P=0.039) and device tortuosity index (DTI) (adjusted OR 8.059; 95% CI 2.867 to 23.428; P<0.001) were independent predictors of SDMS after PED treatment, while the difference in length (DL) (adjusted OR 0.841; 95% CI 0.738 to 0.958; P=0.009) and PED plus coiling (adjusted OR 0.288; 95% CI 0.106 to 0.785; P=0.015) were protective factors. CONCLUSION: The incidence of SDMS after PED treatment of IA was 3.04%. For patients with type I SDMS with incomplete aneurysm occlusion we recommend continuous imaging follow-up while, for patients with type II SDMS, we recommend aggressive retreatment. The DPAD and DTI were independent risk predictors of SDMS after PED treatment, while the DL and PED plus coiling were protective factors.

5.
PLoS One ; 19(4): e0300884, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38603698

RESUMEN

Human-to-human contact plays a leading role in the transmission of infectious diseases, and the contact pattern between individuals has an important influence on the intensity and trend of disease transmission. In this paper, we define regular contacts and random contacts. Then, taking the COVID-19 outbreak in Yangzhou City, China as an example, we consider age heterogeneity, household structure and two contact patterns to establish discrete dynamic models with switching between daytime and nighttime to depict the transmission mechanism of COVID-19 in population. We studied the changes in the reproduction number with different age groups and household sizes at different stages. The effects of the proportion of two contacts patterns on reproduction number were also studied. Furthermore, taking the final size, the peak value of infected individuals in community and the peak value of quarantine infected individuals and nucleic acid test positive individuals as indicators, we evaluate the impact of the number of random contacts, the duration of the free transmission stage and summer vacation on the spread of the disease. The results show that a series of prevention and control measures taken by the Chinese government in response to the epidemic situation are reasonable and effective, and the young and middle-aged adults (aged 18-59) with household size of 6 have the strongest transmission ability. In addition, the results also indicate that increasing the proportion of random contact is beneficial to the control of the infectious disease in the phase with interventions. This work enriches the content of infectious disease modeling and provides theoretical guidance for the prevention and control of follow-up major infectious diseases.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Adulto , Persona de Mediana Edad , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Cuarentena , Brotes de Enfermedades
6.
Anal Chem ; 96(16): 6112-6121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38554137

RESUMEN

Surface-enhanced Raman scattering (SERS) is a powerful analytical technique for chemical identification, but it remains a great challenge to realize the large-scale and well-controlled fabrication of sensitive and repeatable SERS substrates. Here, we report a facile strategy to fabricate centimeter-sized periodic Au nanograting (Au-NG) decorated with well-arranged Ag nanoparticles (Ag-NPs) (denoted as Ag-NPs@Au-NG) as a three-dimensional (3D) flexible hybrid SERS substrate with high sensitivity and good reproducibility. The Au-NG patterns with periodic ridges and grooves are fabricated through nanoimprint lithography by employing a low-cost digital versatile disc (DVD) as a master mold, and the Ag-NPs are assembled by a well-controlled interface self-assembly method without any coupling agents. Multiple coupling electromagnetic field effects are created at the nanogaps between the Ag-NPs and Au-NG patterns, leading to high-density and uniform hot spots throughout the substrate. As a result, the Ag-NPs@Au-NG arrays demonstrate an ultrahigh SERS sensitivity as low as 10-13 M for rhodamine 6G with a high average enhancement factor (EF) of 1.85 × 108 and good signal reproducibility. For practical applications, toxic organic pollutants including crystal violet, thiram, and melamine have been successfully detected with high sensitivity at a low detection limit, showing a good perspective in the rapid detection of toxic organic pollutants.

7.
RSC Adv ; 14(13): 9109-9113, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38500623

RESUMEN

A key factor for boosting oxygen evolution reaction (OER) is the design of heterostructures with steerable defects and interfaces, which can optimize the surface electronic structures and achieve efficient water splitting to produce hydrogen fuel. Herein, we propose a novel one-step hydrothermal approach to fabricate hierarchical Ni3S2 nanowires with an S-doped FeMoO4 nanosheet heterostructure array in situ on Ni-Fe foam (NFF) as a self-standing electrode for synergistically boosted OER. The metalloid Ni3S2 nanowires with good conductivity support the FeMoO4 nanosheets and act as high-speed paths for the charge transfer. Numerous ultrathin S-doped FeMoO4 nanosheets are uniformly distributed on each Ni3S2 nanowire to form heterostructures with larger specific surface area and more revealable active sites, and a strong synergistic effect is created at the heterostructure interfaces to further promote the OER dynamics. Additionally, the NFF serves as the conductive support substrate and simultaneously provides the Ni and Fe sources for the self-growing Ni3S2-FeMoO4, leading to a structurally-integrated electrode with low contact resistance, fast mass transfer, and good stability. Therefore, the Ni3S2-FeMoO4/NFF electrode offers a low overpotential of 331 mV to achieve 500 mA cm-2 and long-term stability at 100 mA cm-2 level for more than 40 h. This work provides insight into the heterostructure of molybdate and sulfide, and a deep understanding of the significance of the synergism in OER operation.

8.
Small ; : e2310530, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317526

RESUMEN

Rechargeable aprotic Li-CO2 batteries have aroused worldwide interest owing to their environmentally friendly CO2 fixation ability and ultra-high specific energy density. However, its practical applications are impeded by the sluggish reaction kinetics and discharge product accumulation during cycling. Herein, a flexible composite electrode comprising CoSe2 nanoparticles embedded in 3D carbonized melamine foam (CoSe2 /CMF) for Li-CO2 batteries is reported. The abundant CoSe2 clusters can not only facilitate CO2 reduction/evolution kinetics but also serve as Li2 CO3 nucleation sites for homogeneous discharge product growth. The CoSe2 /CMF-based Li-CO2 battery exhibits a large initial discharge capacity as high as 5.62 mAh cm-2 at 0.05 mA cm-2 , a remarkably small voltage gap of 0.72 V, and an ultrahigh energy efficiency of 85.9% at 0.01 mA cm-2 , surpassing most of the noble metal-based catalysts. Meanwhile, the battery demonstrates excellent cycling stability of 1620 h (162 cycles) at 0.02 mA cm-2 with an average overpotential of 0.98 V and energy efficiency of 85.4%. Theoretical investigations suggest that this outstanding performance is attributed to the suitable CO2 /Li adsorption and low Li2 CO3 decomposition energy. Moreover, flexible Li-CO2 pouch cell with CoSe2 /CMF cathode displays stable power output under different bending deformations, showing promising potential in wearable electronic devices.

9.
Small Methods ; : e2301759, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381109

RESUMEN

Co-free spinel LiNi0.5 Mn1.5 O4 (LNMO) is emerging as a promising contender for designing next generation high-energy-density and fast-charging Li-ion batteries, due to its high operating voltage and good Li+ diffusion rate. However, further improvement of the Li+ diffusion ability and simultaneous resolution of Mn dissolution still pose significant challenges for their practical application. To tackle these challenges, a simple co-doping strategy is proposed. Compared to Pure-LNMO, the extended lattice in resulting LNMO-SbF sample provides wider Li+ migration channels, ensuring both enhanced Li+ transport kinetics, and lower energy barrier. Moreover, Sb creating structural pillar and stronger TM─F bond together provides a stabilized spinel structure, which stems from the suppression of detrimental irreversible phase transformation during cycling related to Mn dissolution. Benefiting from the synergistic effect, the LNMO-SbF material exhibits a superior reversible capacity (111.4 mAh g-1 at 5C, and 70.2 mAh g-1 after 450 cycles at 10C) and excellent long-term cycling stability at high current density (69.4% capacity retention at 5C after 1000 cycles). Furthermore, the LNMO-SbF//graphite full cell delivers an exceptional retention rate of 96.9% after 300 cycles, and provides a high energy density at 3C even with a high loading. This work provides valuable insight into the design of fast-charging cathode materials for future high energy density lithium-ion batteries.

10.
Langmuir ; 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329721

RESUMEN

The coexistence of lead, zinc, and copper ions in wastewater constitutes an environmental challenge of pressing concern. This research delves into the preparation of innovative oxidation-doped conjugated microporous poly(aniline) frameworks, exploring their prospective efficacy in regulating lead ion adsorption from aqueous solutions. H2SO4-CMPTA demonstrates the capability to reach adsorption equilibrium within 15 min at a lead concentration of 50 ppm. Even at a lead concentration of 20 ppm, it still efficaciously attenuates these levels to sub-10 ppb, a value surpassing extant standard. H2SO4-CMPTA retains over 78.8% adsorption efficiency after six cycles. Analytical characterization coupled with computational calculations suggests that sulfate-coordinated nitrogen cationic structure plays a crucial role in adsorption. A deeper investigation reveals the cardinal role of electrostatic attraction and exclusive chelation adsorption underpinning the efficient capture of lead ions by doped sulfate ions. Intriguingly, in a mixed heavy metal solution containing lead, zinc, and copper ions, H2SO4-CMPTA exhibits an initial predilection toward zinc ions, yet an eventual ion-exchange adsorption gravitating toward lead ions was discerned, governed by the latter's superior binding energy. Our study elucidates a promising material as an efficacious tool for the remediation of aquatic environments tainted with lead contaminants.

11.
J Fungi (Basel) ; 10(1)2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38248980

RESUMEN

The impact of drought stress on plant growth in arid regions is a critical concern, necessitating the exploration of strategies to enhance plant drought resistance, particularly during the early stages of drought stress. This study focuses on the ectomycorrhizal fungus Cenococcum geophilum, renowned for its extensive genetic diversity and broad host compatibility, making it a crucial ally for host plants facing external stresses. We utilized Pinus massoniana seedlings inoculated with different ecotypic strains of C. geophilum under drought stress. The results showed that the inoculation of most strains of C. geophilum enhanced the drought resistance of P. massoniana seedlings under the early stages of drought stress, by influencing the water content, photosynthesis, accumulation of osmotic adjustment substances, and antioxidant enzyme activities in both shoots and roots of seedlings. Transcriptome analysis showed that mycorrhizal seedlings mainly regulated energy metabolism and reduction-oxidation reaction to resist early drought stress. Notably, the level of drought resistance observed in mycorrhizal seedlings was irrespective of the level of drought tolerance of C. geophilum strains. This study contributes essential data for understanding the drought response mechanisms of mycorrhizal P. massoniana seedlings inoculated by distinct C. geophilum ecotypes and guidance on selecting candidate species of ectomycorrhizal fungi for mycorrhizal afforestation in drought areas.

12.
Infect Dis Model ; 9(1): 56-69, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38130878

RESUMEN

In this paper, with the method of epidemic dynamics, we assess the spread and prevalence of COVID-19 after the policy adjustment of prevention and control measure in December 2022 in Taiyuan City in China, and estimate the excess population deaths caused by COVID-19. Based on the transmission mechanism of COVID-19 among individuals, a dynamic model with heterogeneous contacts is established to describe the change of control measures and the population's social behavior in Taiyuan city. The model is verified and simulated by basing on reported case data from November 8th to December 5th, 2022 in Taiyuan city and the statistical data of the questionnaire survey from December 1st to 23rd, 2022 in Neijiang city. Combining with reported numbers of permanent residents and deaths from 2017 to 2021 in Taiyuan city, we apply the dynamic model to estimate theoretical population of 2022 under the assumption that there is no effect of COVID-19. In addition, we carry out sensitivity analysis to determine the propagation character of the Omicron strain and the effect of the control measures. As a result of the study, it is concluded that after adjusting the epidemic policy on December 6th, 2022, three peaks of infection in Taiyuan are estimated to be from December 22nd to 31st, 2022, from May 10th to June 1st, 2023, and from September 5th to October 13th, 2023, and the corresponding daily peaks of new cases can reach 400 000, 44 000 and 22 000, respectively. By the end of 2022, excess deaths can range from 887 to 4887, and excess mortality rate can range from 3.06% to 14.82%. The threshold of the infectivity of the COVID-19 variant is estimated 0.0353, that is if the strain infectivity is above it, the epidemic cannot be control with the previous normalization measures.

13.
Artículo en Inglés | MEDLINE | ID: mdl-38083036

RESUMEN

Speech impairment is one of the most serious problems for patients with communication disorders, e.g., stroke survivors. The brain-computer interface (BCI) systems have shown the potential to alternatively control or rehabilitate the neurological damages in speech production. The effects of different cortical regions in speech-based BCI systems are essential to be studied, which are favorable for improving the performance of speech-based BCI systems. This work aimed to explore the impacts of different speech-related cortical regions in the electroencephalogram (EEG) based classification of seventy spoken Mandarin monosyllables carrying four vowels and four lexical tones. Seven audible speech production-related cortical regions were studied, involving Broca's and Wernicke's areas, auditory cortex, motor cortex, prefrontal cortex, sensory cortex, left brain, right brain, and whole brain. Following the previous studies in which EEG signals were collected from ten subjects during Mandarin speech production, the features of EEG signals were extracted by the Riemannian manifold method, and a linear discriminant analysis (LDA) was regarded as a classifier to classify different vowels and lexical tones. The results showed that when using electrodes from whole brain, the classifier reached the best performances, which were 48.5% for lexical tones and 70.0% for vowels, respectively. The vowel classification results under Broca's and Wernicke's areas, auditory cortex, or prefrontal cortex were higher than those under the motor cortex or sensory cortex. No such differences were observed in the lexical tone classification task.


Asunto(s)
Corteza Auditiva , Habla , Humanos , Electroencefalografía , Encéfalo , Mapeo Encefálico
14.
Transl Stroke Res ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066403

RESUMEN

The pipeline embolization device (PED) is an effective endovascular treatment modality for intracranial aneurysm (IA), but nearly one-fifth of IAs treated with a PED remain persistently filling at 1-year angiography follow-up. Developing a nomogram to predict persistent aneurysm filling after PED treatment can help neurointerventionalists identify aneurysms with incomplete occlusion and change their treatment strategies. This retrospective study included patients with IA treated with a PED from three institutions between April 2016 and April 2022, assigned to a derivation or validation cohort. Multivariate logistic regression analysis was used to identify predictors and develop a nomogram to predict persistent aneurysm filling after PED treatment in the derivation cohort. Predictive accuracy and clinical benefits of the nomogram were assessed using area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis (DCA). In total, 1006 patients with IA were included, 786 in the derivation cohort and 220 in the validation cohort. Over mean follow-up time 18.36 ± 8.58 months, 142 (14.1%) patients developed persistent aneurysm filling after PED treatment, 110 (14.0%) in the derivation cohort and 32 (14.5%) in the validation cohort. In multivariate logistic regression analysis, we developed a nomogram incorporating five predictors: aneurysms located in the basilar artery, dissecting aneurysms, maximum diameter, aneurysms with incorporated branches, and PED plus coiling. AUCs of the nomogram were 0.810 (95% confidence interval [CI], 0.765-0.856) in the derivation cohort and 0.840 (95% CI, 0.754-0.925) in the validation cohort. Calibration curve and DCA analysis demonstrated the utility and clinical application value of this nomogram. This nomogram provides individualized prediction of persistent aneurysm filling after PED treatment for patients with IA, representing a practical approach to effectiveness evaluation. This tool can help neurointerventionalists to identify aneurysms with incomplete occlusion and change their treatment strategy.

15.
Opt Express ; 31(22): 35453-35470, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017715

RESUMEN

X-ray grazing incidence microscopy has extensive applications in the fields of laser inertial confinement fusion and synchrotron radiation. Monte Carlo methods can be used to determine the optical performance of X-ray grazing incidence microscopes and predict the experimental results, which is of great significance for studying physical experiments and diagnostics. In this paper, we proposed a Monte Carlo method based on Geant4 for studying X-ray grazing incidence microscopy. We introduced the G4MultilayerReflection class to describe the physical processes of X-ray multilayer mirrors. We designed a dual-energy Kirkpatrick-Baez microscope that can operate at 6.4 and 9.67 keV simultaneously. Monte Carlo simulations of the spatial resolution and throughput efficiency of the microscope were performed using Geant4, which was assembled and characterized. The spatial resolution results obtained by the Geant4 laboratory simulations, the theoretical model, and the experiments were in good agreement. Additionally, we conducted throughput efficiency calibration experiments for the 6.4 keV imaging channel. The difference between the experimental and Geant4-simulated throughput efficiency was evaluated and resulted in root mean square error values of 8.7% and 9.5% along the Y- and Z-axes, respectively.

16.
Adv Sci (Weinh) ; 10(35): e2301332, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37944509

RESUMEN

Topological transition metal dichalcogenides (TMDCs) have attracted much attention due to their potential applications in spintronics and quantum computations. In this work, the structural and electronic properties of topological TMDCs candidate ZrTe2 are systematically investigated under high pressure. A pressure-induced Lifshitz transition is evidenced by the change of charge carrier type as well as the Fermi surface. Superconductivity is observed at around 8.3 GPa without structural phase transition. A typical dome-shape phase diagram is obtained with the maximum Tc of 5.6 K for ZrTe2 . Furthermore, the theoretical calculations suggest the presence of multiple pressure-induced topological quantum phase transitions, which coexists with emergence of superconductivity. The results demonstrate that ZrTe2 with nontrivial topology of electronic states displays new ground states upon compression.

17.
Molecules ; 28(21)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37959780

RESUMEN

In the ZINC20 database, with the aid of maximum substructure searches, common substructures were obtained from molecules with high-strain-energy and combustion heat values, and further provided domain knowledge on how to design high-energy-density hydrocarbon (HEDH) fuels. Notably, quadricyclane and syntin could be topologically assembled through these substructures, and the corresponding assembled schemes guided the design of 20 fuel molecules (ZD-1 to ZD-20). The fuel properties of the molecules were evaluated by using group-contribution methods and density functional theory (DFT) calculations, where ZD-6 stood out due to the high volumetric net heat of combustion, high specific impulse, low melting point, and acceptable flash point. Based on the neural network model for evaluating the synthetic complexity (SCScore), the estimated value of ZD-6 was close to that of syntin, indicating that the synthetic complexity of ZD-6 was comparable to that of syntin. This work not only provides ZD-6 as a potential HEDH fuel, but also illustrates the superiority of learning design strategies from the data in increasing the understanding of structure and performance relationships and accelerating the development of novel HEDH fuels.

18.
Neurochem Int ; 171: 105638, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37923297

RESUMEN

Aberrant microglial activation is a prominent feature of neuroinflammation, which is implicated in the pathogenesis of neurological disorders. Fc receptor common γ-chain (FcRγ), one of the two immunoreceptor tyrosine-based activation motif-bearing adaptor proteins, is abundantly expressed in microglia. It couples with different receptors, such as receptors for the Fc portion of IgG. In this study, we observed increased FcRγ expression along with increased IgG-binding during acute neuroinflammation triggered by MPTP intoxication, where adaptive immune responses should not be involved. Notably, FcRγ was expressed not only in the cell membrane but also in the cytoplasm in the activated microglia. FcRγ deficiency exacerbated microglial activation, pro-inflammatory factor upregulation, nigral dopaminergic neuronal loss and motor deficits, implicating a beneficial role of FcRγ in this model. Blockade of Fcγ receptor ligation by IgG in mice by Endoglycosidase S treatment, a bacterial endo-ß-N-acetylglucosaminidase cleaving specifically the Asn297-linked glycan of IgG, or by using the mice deficient in mature B cells (muMT) with IgG production defects, did not show similar phenotypes to those observed in FcRγ-deficient mice, indicating that the beneficial effect mediated by FcRγ did not depend on FcγR ligation by IgG. Further, FcRγ knockout aggravated the expression and activation of STAT1 in microglia, suggesting FcRγ modulated neuroinflammation by dampening STAT1 signaling. Collectively, these results revealed that FcRγ-associated receptors could function as negative regulators of neuroinflammation and dopaminergic neurodegeneration.


Asunto(s)
Receptores Fc , Receptores de IgG , Ratones , Animales , Receptores de IgG/genética , Receptores de IgG/metabolismo , Ratones Noqueados , Enfermedades Neuroinflamatorias , Inmunidad , Inmunoglobulina G , Ratones Endogámicos C57BL
19.
Artículo en Inglés | MEDLINE | ID: mdl-37879671

RESUMEN

Yolk-shell metal-organic framework (YS-MOF) liquids are candidate materials in large-size species with high-efficiency separation, owing to their hierarchical porosity, faster mass transfer, better compatibility, and higher solution processability than MOF liquids with micropores. Nevertheless, facile synthesis strategies of yolk-shell porous ionic liquids (YSPILs) with regulations of size and morphology are an ongoing challenge. Herein, we propose a general strategy to construct YSPILs based on Z67@PDA with tunable core sizes and morphologies. Benefiting from the unique hierarchical yolk-shell structure, as-prepared YSPILs exhibit promise in C3H6/C3H8 capture and separation with the increased sizes of core in yolk-shell ZIF-67@PDA. Advanced YS-MOF liquids have improved the adsorption properties and increased our ability to tailor chemical composition and pore architecture. Impressively, the adsorption capacity of C3H6 and C3H8 of YSPILs exhibits an approximately 3-fold enhancement compared with that of the neat ILs, confirming that the accessible porosities are retained. Effective C3H6/C3H8 separation performance of YSPILs over PILs based on ZIF-67, revealing the hierarchical porosity of YS-Z67@PDA liquids, benefits larger-size gas separation. Therefore, we believe that this work can not only help us to rationally design novel hierarchically porous ionic liquids but also promote candidate applications in large-size species separation, catalysis, and nanoreactors.

20.
Mol Psychiatry ; 28(9): 3795-3805, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37658228

RESUMEN

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders with a strong genetic liability. Despite extensive studies, however, the underlying pathogenic mechanism still remains elusive. In the present study, we identified a homozygous mutation in the intron 1 of Wnt1 via large-scale screening of ASD risk/causative genes and verified that this mutation created a new splicing donor site in the intron 1, and consequently, a decrease of WNT1 expression. Interestingly, humanized rat models harboring this mutation exhibited robust ASD-like behaviors including impaired ultrasonic vocalization (USV), decreased social interactions, and restricted and repetitive behaviors. Moreover, in the substantia nigra compacta (SNpc) and the ventral tegmental area (VTA) of mutant rats, dopaminergic (DAergic) neurons were dramatically lost, together with a comparable decrease in striatal DAergic fibers. Furthermore, using single-cell RNA sequencing, we demonstrated that the decreased DAergic neurons in these midbrain areas might attribute to a shift of the boundary of the local pool of progenitor cells from the hypothalamic floor plate to the midbrain floor plate during the early embryonic stage. Moreover, treatments of mutant rats with levodopa could attenuate the impaired USV and social interactions almost completely, but not the restricted and repetitive behaviors. Our results for the first time documented that the developmental loss of DAergic neurons in the midbrain underlies the pathogenesis of ASD, and that the abnormal progenitor cell patterning is a cellular underpinning for this developmental DAergic neuronal loss. Importantly, the effective dopamine therapy suggests a translational significance in the treatment of ASD.


Asunto(s)
Trastorno del Espectro Autista , Neuronas Dopaminérgicas , Animales , Ratas , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/metabolismo , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Intrones , Mesencéfalo/metabolismo , Sustancia Negra/metabolismo , Área Tegmental Ventral/metabolismo
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