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1.
Nat Commun ; 15(1): 2284, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480794

RESUMO

Banna virus (BAV) is the prototype Seadornavirus, a class of reoviruses for which there has been little structural study. Here, we report atomic cryo-EM structures of three states of BAV virions-surrounded by 120 spikes (full virions), 60 spikes (partial virions), or no spikes (cores). BAV cores are double-layered particles similar to the cores of other non-turreted reoviruses, except for an additional protein component in the outer capsid shell, VP10. VP10 was identified to be a cementing protein that plays a pivotal role in the assembly of BAV virions by directly interacting with VP2 (inner capsid), VP8 (outer capsid), and VP4 (spike). Viral spikes (VP4/VP9 heterohexamers) are situated on top of VP10 molecules in full or partial virions. Asymmetrical electrostatic interactions between VP10 monomers and VP4 trimers are disrupted by high pH treatment, which is thus a simple way to produce BAV cores. Low pH treatment of BAV virions removes only the flexible receptor binding protein VP9 and triggers significant conformational changes in the membrane penetration protein VP4. BAV virions adopt distinct spatial organization of their surface proteins compared with other well-studied reoviruses, suggesting that BAV may have a unique mechanism of penetration of cellular endomembranes.


Assuntos
Coltivirus , Reoviridae , Coltivirus/metabolismo , Microscopia Crioeletrônica , Reoviridae/metabolismo , Proteínas do Capsídeo/metabolismo , Vírion/metabolismo
2.
Sci Total Environ ; 926: 171943, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527546

RESUMO

Monoculture plantations in China, characterized by the continuous cultivation of a single species, pose challenges to timber accumulation and understory biodiversity, raising concerns about sustainability. This study investigated the impact of continuous monoculture plantings of Chinese fir (Cunninghamia lanceolata [Lamb.] Hook.) on soil properties, dissolved organic matter (DOM), and microorganisms over multiple generations. Soil samples from first to fourth-generation plantations were analyzed for basic chemical properties, DOM composition using Fourier transform ion cyclotron resonance mass spectrometry, and microorganisms via high-throughput sequencing. Results revealed a significant decline in nitrate nitrogen content with successive rotations, accompanied by an increase in easily degradable compounds like carbohydrates, aliphatic/proteins, tannins, Carbon, Hydrogen, Oxygen and Nitrogen- (CHON) and Carbon, Hydrogen, Oxygen and Sulfur- (CHOS) containing compounds. However, the recalcitrant compounds, such as lignin and carboxyl-rich alicyclic molecules (CRAMs), condensed aromatics and Carbon, Hydrogen and Oxygen- (CHO) containing compounds decreased. Microorganism diversity, abundance, and structure decreased with successive plantations, affecting the ecological niche breadth of fungal communities. Bacterial communities were strongly influenced by DOM composition, particularly lignin/CRAMs and tannins. Continuous monoculture led to reduced soil nitrate, lignin/CRAMs, and compromised soil quality, altering chemical properties and DOM composition, influencing microbial community assembly. This shift increased easily degraded DOM, accelerating soil carbon and nitrogen cycling, ultimately reducing soil carbon sequestration. From environmental point of view, the study emphasizes the importance of sustainable soil management practices in continuous monoculture systems. Particularly the findings offer valuable insights for addressing challenges associated with monoculture plantations and promoting long-term ecological sustainability.


Assuntos
Cunninghamia , Microbiota , Matéria Orgânica Dissolvida , Nitratos/análise , Lignina/metabolismo , Taninos/análise , Taninos/metabolismo , Solo/química , Compostos Orgânicos/análise , Compostos de Enxofre/metabolismo , Nitrogênio/análise , Carbono/análise , Hidrogênio/análise , Oxigênio/análise
3.
Angew Chem Int Ed Engl ; 63(17): e202318568, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38433368

RESUMO

ATR has emerged as a promising target for anti-cancer drug development. Several potent ATR inhibitors are currently undergoing various stages of clinical trials, but none have yet received FDA approval due to unclear regulatory mechanisms. In this study, we discovered a potent and selective ATR degrader. Its kinase-independent regulatory functions in acute myeloid leukemia (AML) cells were elucidated using this proteolysis-targeting chimera (PROTAC) molecule as a probe. The ATR degrader, 8 i, exhibited significantly different cellular phenotypes compared to the ATR kinase inhibitor 1. Mechanistic studies revealed that ATR deletion led to breakdown in the nuclear envelope, causing genome instability and extensive DNA damage. This would increase the expression of p53 and triggered immediately p53-mediated apoptosis signaling pathway, which was earlier and more effective than ATR kinase inhibition. Based on these findings, the in vivo anti-proliferative effects of ATR degrader 8 i were assessed using xenograft models. The degrader significantly inhibited the growth of AML cells in vivo, unlike the ATR inhibitor. These results suggest that the marked anti-AML activity is regulated by the kinase-independent functions of the ATR protein. Consequently, developing potent and selective ATR degraders could be a promising strategy for treating AML.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Proteína Supressora de Tumor p53/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proteólise , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/uso terapêutico
4.
Biomimetics (Basel) ; 9(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38392130

RESUMO

Inverse optimal control is a method for recovering the cost function used in an optimal control problem in expert demonstrations. Most studies on inverse optimal control have focused on building the unknown cost function through the linear combination of given features with unknown cost weights, which are generally considered to be constant. However, in many real-world applications, the cost weights may vary over time. In this study, we propose an adaptive online inverse optimal control approach based on a neural-network approximation to address the challenge of recovering time-varying cost weights. We conduct a well-posedness analysis of the problem and suggest a condition for the adaptive goal, under which the weights of the neural network generated to achieve this adaptive goal are unique to the corresponding inverse optimal control problem. Furthermore, we propose an updating law for the weights of the neural network to ensure the stability of the convergence of the solutions. Finally, simulation results for an example linear system are presented to demonstrate the effectiveness of the proposed strategy. The proposed method is applicable to a wide range of problems requiring real-time inverse optimal control calculations.

5.
Small ; : e2310591, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409636

RESUMO

The family of polar hybrid perovskites, in which bulk photovoltaic effects (BPVEs) drive steady photocurrent without bias voltage, have shown promising potentials in self-powered polarization-sensitive photodetection. However, reports of BPVEs in 3D perovskites remain scare, being mainly hindered by the limited dipole moment or lack of symmetry breaking. Herein, a polar 3D perovskitoid, (BDA)Pb2 Br6 (BDA = NH3 C4 H8 NH3 ), where the spontaneous polarization (Ps )-induced BPVE drives self-powered photodetection of polarized-light is reported. Emphatically, the edge-sharing Pb2 Br10 dimer building unit allows the optical anisotropy and polarity in 3D (BDA)Pb2 Br6 , which triggers distinct optical absorption dichroism ratio of ≈2.80 and BPVE dictated photocurrent of 3.5 µA cm-2 . Strikingly, these merits contribute to a polarization-sensitive photodetection with a high polarization ratio (≈4) under self-powered mode, beyond those of 2D hybrid perovskites and inorganic materials. This study highlights the potential of polar 3D perovskitoids toward intelligent optoelectronic applications.

6.
ACS Appl Mater Interfaces ; 16(9): 11694-11703, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38387044

RESUMO

Recently, photodetectors based on perovskite nanoplatelets (NPLs) have attracted considerable attention in the visible spectral region owing to their large absorption cross-section, high exciton binding energy, excellent charge transfer properties, and appropriate flexibility. However, their stability and performance are still challenging for perovskite NPL photodetectors. Here, a surface engineering strategy to enhance the optical stability of blue-light CsPbBr3 NPLs by acetylenedicarboxylic acid (ATDA) treatment has been developed. ATDA has strong binding capacity and a short chain length, which can effectively passivate defects and significantly improve the photoluminescence quantum efficiency, stability, and carrier mobility of NPLs. As a result, ATDA-treated CsPbBr3 NPLs exhibit improved optical properties in both solutions and films. The NPL solution maintains high PL performance even after being heated at 80 °C for 2 h, and the NPL film remains nondegradable after 4 h of exposure to ultraviolet irradiation. Especially, photodetectors based on the treated CsPbBr3 NPL films demonstrate exceptional performance, especially when the detectivity approaches up to 9.36 × 1012 Jones, which can be comparable to the best CsPbBr3 NPL photodetectors ever reported. More importantly, the assembled devices demonstrated high stability (stored in an air environment for more than 30 days), significantly exceeding that of untreated NPLs.

7.
PLoS Pathog ; 20(2): e1011948, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38300972

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is a highly pathogenic tick-borne virus, prevalent in more than 30 countries worldwide. Human infection by this virus leads to severe illness, with an average case fatality of 40%. There is currently no approved vaccine or drug to treat the disease. Neutralizing antibodies are a promising approach to treat virus infectious diseases. This study generated 37 mouse-derived specific monoclonal antibodies against CCHFV Gc subunit. Neutralization assays using pseudotyped virus and authentic CCHFV identified Gc8, Gc13, and Gc35 as neutralizing antibodies. Among them, Gc13 had the highest neutralizing activity and binding affinity with CCHFV Gc. Consistently, Gc13, but not Gc8 or Gc35, showed in vivo protective efficacy (62.5% survival rate) against CCHFV infection in a lethal mouse infection model. Further characterization studies suggested that Gc8 and Gc13 may recognize a similar, linear epitope in domain II of CCHFV Gc, while Gc35 may recognize a different epitope in Gc. Cryo-electron microscopy of Gc-Fab complexes indicated that both Gc8 and Gc13 bind to the conserved fusion loop region and Gc13 had stronger interactions with sGc-trimers. This was supported by the ability of Gc13 to block CCHFV GP-mediated membrane fusion. Overall, this study provides new therapeutic strategies to treat CCHF and new insights into the interaction between antibodies with CCHFV Gc proteins.


Assuntos
Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Animais , Camundongos , Humanos , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Anticorpos Monoclonais , Microscopia Crioeletrônica , Anticorpos Neutralizantes , Epitopos
8.
Int J Mol Med ; 53(3)2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38214291

RESUMO

Diabetic wounds remain a great challenge for clinicians globally as a lack of effective radical treatment often results in poor prognosis. Exosomes derived from adipose­derived stem cells (ADSC­Exos) have been explored as an appealing nanodrug delivery system in the treatment of diabetic wounds. However, the short half­life and low utilization efficiency of exosomes limit their therapeutic effects. Low­intensity pulsed ultrasound (LIPUS) provides a non­invasive mechanical stimulus to cells and exerts a number of biological effects such as cavitation and thermal effects. In the present study, whether LIPUS could enhance ADSC­Exo­mediated diabetic wound repair was investigated and its possible mechanism of action was explored. After isolation and characterization, ADSC­Exos were injected into mice with diabetic wounds, then the mice were exposed to LIPUS irradiation. The control mice were subcutaneously injected with PBS. Wound healing assays, laser Doppler perfusion, Masson's staining and angiogenesis assays were used to assess treatment efficiency. Then, ADSC­Exos were cocultured with human umbilical vein endothelial cells (HUVECs), and the proliferation, migration and tube formation of HUVECs were assessed. Moreover, the cellular uptake of ADSC­Exos in vitro and in vivo was assessed to explore the synergistic mechanisms underlying the effects of LIPUS. The in vivo results demonstrated that LIPUS increased the uptake of exosomes and prolonged the residence of exosomes in the wound area, thus enhancing angiogenesis and accelerating wound repair in diabetic mice. The in vitro results further confirmed that LIPUS enhanced the uptake efficiency of ADSC­Exos by 10.93­fold and significantly increased the proliferation, migration and tubular formation of HUVECs. Therefore, the present study indicates that LIPUS is a promising strategy to improve the therapeutic effects of ADSC­Exos in diabetic wounds by promoting the cellular uptake of exosomes and enhancing angiogenesis.


Assuntos
Diabetes Mellitus Experimental , Exossomos , Humanos , Camundongos , Animais , Diabetes Mellitus Experimental/terapia , 60489 , Cicatrização , Células Endoteliais da Veia Umbilical Humana , Ondas Ultrassônicas
9.
Int Wound J ; 21(1): e14403, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37735819

RESUMO

This analysis systematically reviewed the efficacy of evidence-based care on diabetic foot ulcers. A computerised literature search was conducted for randomised controlled studies (RCTs) of evidence-based care interventions for the treatment of diabetic foot ulcers using the PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM) and Wanfang databases from the date of inception of each database to June 2023. The articles were independently screened, data were extracted by two researchers, and the quality of each study was assessed using the Cochrane bias assessment tool. Meta-analysis of the data was performed using RevMan 5.4 software. Twenty-five RCTs with a total of 2272 patients were included. Meta-analysis showed that, compared with other care methods, evidence-based care significantly improved the treatment efficacy of diabetic foot ulcers (odds ratio: 3.91, 95% confidence interval [CI]: 2.76 to 5.53, p < 0.001) and significantly reduced their fasting plasma glucose (mean difference [MD]: -1.10, 95% CI: -1.24 to -0.96, p < 0.001), 2-h postprandial glucose (2hPG) (MD: -1.69, 95% CI: -2.07 to -1.31, p < 0.001) and glycated haemoglobin (HbA1c) (MD: -0.71, 95% CI: -0.94 to -0.48, p < 0.001). Evidence-based care intervention is effective at reducing FPG, 2hPG and HbA1c levels and improving treatment efficacy in patients with diabetic foot ulcers.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/terapia , Medicina Baseada em Evidências , Hemoglobinas Glicadas , Resultado do Tratamento , China
10.
Small ; 20(8): e2305990, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37821401

RESUMO

Halide composition engineering has been demonstrated as an effective strategy for optical and electronic properties modulation in 3D perovskites. While the impact of halide mixing on the structural and charge transport properties of 3D perovskitoids remains largely unexplored. Herein, it is demonstrated that bromine (Br) mixing in 3D (NMPDA)Pb2 I6 (NMPDA = N-methyl-1,3-propane diammonium) perovskitoid yields stabilized (NMPDA)Pb2 I4 Br2 with specific ordered halide sites, where Br ions locate at the edge-sharing sites. The halide ordered structure enables stronger H-bonds, shorter interlayer distance, and lower octahedra distortion in (NMPDA)Pb2 I4 Br2 with respect to the pristine (NMPDA)Pb2 I6 . These attributes further result in high ion migration activation energy, low defect states density, and enhanced carrier mobility-lifetime product (µτ), as underpinned by the electrical properties investigation and DFT calculations. Remarkably, the parallel configured photodetector based on (NMPDA)Pb2 I4 Br2 single crystal delivers a high on/off current ratio of 3.92 × 103 , a satisfying photoresponsivity and detectivity of 0.28 A W-1 and 3.05 × 1012 Jones under 10.94 µW cm-2 irradiation, superior to that of (NMPDA)Pb2 I6 and the reported 3D perovskitoids. This work sheds novel insight on exploring 3D mixed halide perovskitoids toward advanced and stable optoelectronic devices.

11.
Nanoscale ; 16(2): 504-526, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38108473

RESUMO

Silicon carbide (SiC) nanomaterials have emerged as promising candidates for supercapacitor electrodes due to their unique properties, which encompass a broad electrochemical stability range, exceptional mechanical strength, and resistance to extreme conditions. This review offers a comprehensive overview of the latest advancements in SiC nanomaterials for supercapacitors. It encompasses diverse synthesis methods for SiC nanomaterials, including solid-state, gas-phase, and liquid-phase synthesis techniques, while also discussing the advantages and challenges associated with each method. Furthermore, this review places a particular emphasis on the electrochemical performance of SiC-based supercapacitors, highlighting the pivotal role of SiC nanostructures and porous architectures in enhancing specific capacitance and cycling stability. A deep dive into SiC-based composite materials, such as SiC/carbon composites and SiC/metal oxide hybrids, is also included, showcasing their potential to elevate energy density and cycling stability. Finally, the paper outlines prospective research directions aimed at surmounting existing challenges and fully harnessing SiC's potential in the development of next-generation supercapacitors.

12.
J Phys Chem Lett ; 15(1): 201-211, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38157217

RESUMO

Indium phosphide (InP) and zinc selenium tellurium (ZnSeTe) quantum dots (QDs) as less toxic alternatives have received substantial attention. The structure of QDs generally consists of a QD core, inner shell layer, and outer shell layer. We reckon that the inner shell layer, especially its components and thickness, have a significant influence on the optical and electronic performances of QDs. In this Perspective, we compare optical properties of these QDs with different inner shells and summarize how typical inner shell components and thickness influence their optical properties. The impact of the inner shell on the performance of QD light-emitting diodes (QLEDs) has also been discussed. The appropriate components and thickness of the inner shell both contribute to alleviate valence or lattice mismatch, thereby enhancing the performance of QDs. We expect that this Perspective could heighten awareness of the significance and impact of the inner shell layer in QDs and facilitate further development of QDs and QLEDs.

13.
J Phys Chem Lett ; 14(51): 11543-11549, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38095940

RESUMO

Mn2+ doped perovskite nanocrystals have garnered significant attention in optoelectronic applications. However, the synthesis of Mn2+ doped perovskite nanowires (NWs) poses challenges, and the dynamics of energy transfer from the exciton to Mn2+ remains unexplored, which is crucial for optimizing Mn2+ luminescence efficiency. Herein, we present a method to synthesize Mn2+ doped CsPbBr3 NWs with a photoluminescence quantum yield of 52% by diffusing Mn2+ into seed CsPbBr3 NWs grown via a hot injection method. We control the solution and lattice chemical potentials of Pb2+ and Mn2+ to enable Mn2+ to diffuse into the CsPbBr3 NWs while minimizing Ostwald ripening. Variable temperature photoluminescence spectroscopy reveals that the energy transfer from the exciton to Mn2+ in Mn2+ doped CsPbBr3 NWs is temperature dependent. A dynamic competition is observed between energy transfer and backward energy transfer, resulting in stronger Mn2+ photoluminescence at 80 K. This work provides a specific synthesis pathway for Mn2+ doped CsPbBr3 NWs and sheds light on their exciton-to-Mn2+ energy transfer dynamics.

14.
Infect Med (Beijing) ; 2(3): 212-223, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38073882

RESUMO

Background: West Nile virus is a severe zoonotic pathogen that can cause severe central nervous system symptoms in humans and horses, and is fatal for birds, chickens and other poultry. With no specific drugs or vaccines available, antibody-based therapy is a promising treatment. This study aims to develop neutralizing antibodies against West Nile virus and assess their cross-protective potential against Japanese encephalitis virus. Methods: Monoclonal antibodies against WNV and JEV were isolated by hybridoma technology. The therapeutic efficacy of these antibodies was evaluated using a mouse model, and a humanized version of the monoclonal antibody was generated for potential human application. Results: In this study, we generated eight monoclonal antibodies that exhibit neutralizing activity against WNV. Their therapeutic effects against WNV were validated both in vivo and in vitro. Among these antibodies, C9-G11-F3 also exhibited cross-protective activity against JEV. We also humanized the antibody to ensure that it could be used for WNV infection treatment in humans. Conclusion: This study highlights the importance of neutralizing antibodies as a promising approach for protection against West Nile virus infection and suggests their potential utility in the development of therapeutic interventions.

15.
Hortic Res ; 10(11): uhad200, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023477

RESUMO

Cassava is a crucial crop that makes a significant contribution to ensuring human food security. However, high-quality telomere-to-telomere cassava genomes have not been available up to now, which has restricted the progress of haploid molecular breeding for cassava. In this study, we constructed two nearly complete haploid resolved genomes and an integrated, telomere-to-telomere gap-free reference genome of an excellent cassava variety, 'Xinxuan 048', thereby providing a new high-quality genomic resource. Furthermore, the evolutionary history of several species within the Euphorbiaceae family was revealed. Through comparative analysis of haploid genomes, it was found that two haploid genomes had extensive differences in linear structure, transcriptome features, and epigenetic characteristics. Genes located within the highly divergent regions and differentially expressed alleles are enriched in the functions of auxin response and the starch synthesis pathway. The high heterozygosity of cassava 'Xinxuan 048' leads to rapid trait segregation in the first selfed generation. This study provides a theoretical basis and genomic resource for molecular breeding of cassava haploids.

16.
Commun Biol ; 6(1): 1086, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884600

RESUMO

Feed quality influences insect cannibalistic behavior and gut microbial communities. In the present study, Spodoptera exigua larvae were fed six different artificial diets, and one of these diets (Diet 3) delayed larval cannibalistic behavior and reduced the cannibalism ratio after ingestion. Diet 3-fed larvae had the highest gut bacterial load (1.396 ± 0.556 × 1014 bacteria/mg gut), whereas Diet 2-fed larvae had the lowest gut bacterial load (3.076 ± 1.368 × 1012 bacteria/mg gut). The gut bacterial composition and diversity of different diet-fed S. exigua larvae varied according to the 16S rRNA gene sequence analysis. Enterobacteriaceae was specific to the Diet 3-fed larval gut. Fifteen culturable bacterial isolates were obtained from the midgut of Diet 3-fed larvae. Of these, ten belonged to Escherichia sp. After administration with Diet 1- or 2-fed S. exigua larvae, two bacterial isolates (SePC-12 and -37) delayed cannibalistic behavior in both tested larval groups. Diet 2-fed larvae had the lowest Juvenile hormone (JH) concentration and were more aggressive against intraspecific predation. However, SePC-12 loading increased the JH hormone levels in Diet 2-fed larvae and inhibited their cannibalism. Bacteria in the larval midgut are involved in the stabilization of JH levels, thereby regulating host larval cannibalistic behavior.


Assuntos
Canibalismo , Escherichia , Animais , Spodoptera/genética , Larva/fisiologia , RNA Ribossômico 16S/genética , Bactérias
17.
Toxicology ; 499: 153650, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37858774

RESUMO

BACKGROUND: Exposure to di-(2-ethylhexyl) phthalate (DEHP) can cause neurotoxicity but the mechanism is not clear. Blood brain barrier (BBB) is one of the most important tissues to protect the brain. However, whether DEHP can disrupt the BBB or not remains unclear. The objective of this study is to investigate the potential effects of subchronic DEHP exposure on BBB integrity and discuss the role of BBB in DEHP inducible neurotoxicity with an emphasis on neuroinflammatory responses. Male adult C57BL/6J mice were orally administered with vehicle or 200 or 750 mg/kg/day DEHP for 90 days. Subchronic exposure to high-dose DEHP increased water intake but decreased body weight and brain weight. The concentrations of DEHP metabolites increased in serum from all DEHP-exposed groups while increased in brain only from the high-dose group. DEHP induced neurobehavioural alterations and damaged hippocampal neurons. DEHP increased BBB permeability by Evans blue (EB) extravasation and decreased tight junction proteins (ZO-1, occludin, and claudin-5) while presenting a neuroinflammatory feature characterized by the upregulated inflammatory mediators TNF-α and the NLRP3/caspase-1/IL-1ß inflammasome pathway. Our data provide new insights into neurotoxicity caused by subchronic DEHP exposure, which is probably involved in BBB dysfunction and neuroinflammatory responses.


Assuntos
Barreira Hematoencefálica , Dietilexilftalato , Camundongos , Animais , Masculino , Dietilexilftalato/toxicidade , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias , Inflamação/induzido quimicamente
19.
Signal Transduct Target Ther ; 8(1): 347, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37704615

RESUMO

Coronavirus disease 2019 (COVID-19) was first reported three years ago, when a group of individuals were infected with the original SARS-CoV-2 strain, based on which vaccines were developed. Here, we develop six human monoclonal antibodies (mAbs) from two elite convalescents in Wuhan and show that these mAbs recognize diverse epitopes on the receptor binding domain (RBD) and can inhibit the infection of SARS-CoV-2 original strain and variants of concern (VOCs) to varying degrees, including Omicron strains XBB and XBB.1.5. Of these mAbs, the two most broadly and potently neutralizing mAbs (7B3 and 14B1) exhibit prophylactic activity against SARS-CoV-2 WT infection and therapeutic effects against SARS-CoV-2 Delta variant challenge in K18-hACE2 KI mice. Furthermore, post-exposure treatment with 7B3 protects mice from lethal Omicron variants infection. Cryo-EM analysis of the spike trimer complexed with 14B1 or 7B3 reveals that these two mAbs bind partially overlapped epitopes onto the RBD of the spike, and sterically disrupt the binding of human angiotensin-converting enzyme 2 (hACE2) to RBD. Our results suggest that mAbs with broadly neutralizing activity against different SARS-CoV-2 variants are present in COVID-19 convalescents infected by the ancestral SARS-CoV-2 strain, indicating that people can benefit from former infections or vaccines despite the extensive immune escape of SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Animais , Camundongos , Anticorpos Amplamente Neutralizantes , Anticorpos Monoclonais , Epitopos/genética
20.
Chem Commun (Camb) ; 59(79): 11795-11798, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37706286

RESUMO

Broadband emissions from low-dimensional hybrid perovskites have aroused intense interest. However, the achievement of broadband red emission in lead halide perovskites remains challenging. Herein, we report a one-dimensional (1D) hybrid lead bromide perovskitoid, (HM)Pb2Br6 (HM = hexamethonium), featuring a corrugated "3 × 3" [Pb2Br6]2- chain. The unique structure results in intriguingly red emission peaking at 692 nm, with a PLQY of around 6.24%. Our spectroscopic and computational studies reveal that the red emission derives from self-localized Pb23+, Pb3+ and Br2- species confined within the inorganic lead bromide lattice that function as radiative centres. This finding will benefit the design of perovskite systems for efficient red emission.

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