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1.
J Am Chem Soc ; 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36411055

RESUMO

Biological systems employ non-equilibrium self-assembly to create ordered nanoarchitectures with sophisticated functions. However, it is challenging to construct artificial non-equilibrium nanoassemblies due to lack of control over assembly dynamics and kinetics. Herein, we design a series of linear polymers with different side groups for further coordination-driven self-assembly based on shape-complementarity. Such a design introduces a main-chain confinement which effectively slows down the assembly process of side groups, thus allowing us to monitor the real-time evolution of lychee-like nanostructures. The function related to the non-equilibrium nature is further explored by performing photothermal conversion study. The ability to observe and capture non-equilibrium states in this supramolecular system will enhance our understanding of the thermodynamic and kinetic features as well as functions of living systems.

3.
Chemistry ; 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36448358

RESUMO

Polyanion-type Na4Fe3(PO4)2(P2O7) (NFPP) is a promising cathode material for sodium-ion batteries due to its low cost and high safety. Herein, a three-dimensional (3D) holey graphene (HG) decorated NFPP/C material (NFPPCHG) has been successfully prepared by a simple and scalable ball milling strategy with sodium phytate and ferrous oxalate as precursors. The introduction of HG can obviously improve the specific surface area, electronic conductivity and ions transport performance of NFPPCHG, and largely enhance its electrochemical properties. The prepared NFPPCHG delivers a high reversible capacity of 118 mAh g-1 at 0.2 C and keeps a considerable capacity of 53 mAh g-1 even at an ultrahigh rate of 100 C. NFPPCHG also shows excellent performance at 55 °C and -20 °C. Moreover, in-situ distribution of relaxation time analysis further demonstrates NFPPCHG has superior electrochemical kinetics. In addition, HC//NFPPCHG full cell displays good performance, suggesting great potential of the prepared material for practical applications.

4.
Nat Chem ; 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329179

RESUMO

Identification and quantification of synthetic polymers in complex biological milieu are crucial for delivery, sensing and scaffolding functions, but conventional techniques based on imaging probe labellings only afford qualitative results. Here we report modular construction of precise sequence-defined amphiphilic polymers that self-assemble into digital micelles with contour lengths strictly regulated by oligourethane sequences. Direct sequence reading is accomplished with matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry, facilitated by high-affinity binding of alkali metal ions with poly(ethylene glycol) dendrons and selective cleavage of benzyl-carbamate linkages. A mixture of four types of digital micelles could be identified, sequence-decoded and quantified by MALDI and MALDI imaging at cellular, organ and tissue slice levels upon in vivo administration, enabling direct comparison of biological properties for each type of digital micelle in the same animal. The concept of digital micelles and encoded amphiphiles capable of direct sequencing and high-throughput label-free quantification could be exploited for next-generation precision nanomedicine designs (such as digital lipids) and protein corona studies.

5.
Front Public Health ; 10: 1005647, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225786

RESUMO

Urban green space can supply a range of ecosystem services and general health benefits for people. This paper reviewed and analyzed 607 papers related to urban green space and health behaviors from 2002 to 2021 in the Web of Science core collection by using Citespace 6.1.R2 software. The scientifically bibliometric analysis and visual analysis were conducted to analyze the basic characteristics, literature co-citation analysis, research hotspots, and frontier trends. The findings show that 11 co-citation clusters indicate the research intellectual base. Also, 19 main keywords with a high frequency and 20 main keywords with a high centrality were extracted. Burst detection analysis reveals three research frontier trends: the correlation between urban green space and health behavior; the driving and impact factors; and the study of environmental justice and social equity. This paper aims to systematically review the progress and basic situation of urban green spaces and health behaviors research around the world, which helps to gain a comprehensive understanding of this field, as well as provide value and references for subsequent research.


Assuntos
Ecossistema , Parques Recreativos , Bibliometria , Comportamentos Relacionados com a Saúde , Humanos
6.
Opt Express ; 30(18): 31584-31601, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242238

RESUMO

We investigate the near-field radiative heat transfer in a three-body system made of Weyl semimetals. At infinitesimal temperature gradient, the rotation of the middle and the right bodies leads to heat transfer suppression, enabling thermal switching with considerably enhanced heat flux but slightly smaller ratio than two-body system without the middle body, due to stronger cavity surface plasmon polariton modes and their mismatch caused by relative rotation. By further moving the middle body to induce asymmetric cavity sizes, the three-body system can achieve a switching ratio exceeding the two-body counterpart due to asymmetric cavity modes coupling. As the temperature gradient increases to 200 K, the highest switching ratio by optimally tuning the rotation and cavity size asymmetry decreases slightly yet still outperforms the two-body system. Our results provide important understanding of the near-field radiative heat transfer in many-body systems consisting of Weyl semimetals.

7.
Opt Express ; 30(21): 38423, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258407

RESUMO

This erratum corrects a typographical error in Eq. (4) of our published paper [Opt. Express30(18), 31584 (2022).10.1364/OE.465017]. This misprint does not influence the results and conclusions presented in the original Article.

8.
Phys Rev Lett ; 129(16): 163602, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306767

RESUMO

We systematically study the decay of quasi-two-dimensional vortices in an oblate strongly interacting Fermi gas over a wide interaction range and observe that, as the system temperature is lowered, the vortex lifetime increases in the Bose-Einstein condensate (BEC) regime but decreases at unitarity and in the Bardeen-Cooper-Schrieffer (BCS) regime. The observations can be qualitatively captured by a phenomenological model simply involving diffusion and two-body collisional loss, in which the vortex lifetime is mostly determined by the slower process of the two. In particular, the counterintuitive vortex decay in the BCS regime can be interpreted by considering the competition between the temperature dependence of the vortex annihilation rate and that of unpaired fermions. Our results suggest a competing mechanism for the complex vortex decay dynamics in the BCS-BEC crossover for the fermionic superfluids.

9.
Fish Shellfish Immunol ; 131: 757-765, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36280129

RESUMO

Cysteinyl aspartate specific proteinase-3 (Caspase-3) is an important protein involved in the apoptosis and gasdermin E (GSDME)-mediated cell pyroptosis pathways in vertebrates. A Caspase-3 homologue (designated as CgCaspase-3) was previously identified as an immune receptor specific for lipopolysaccharide (LPS) to regulate apoptosis in the Pacific oyster Crassostrea gigas. In the present study, the binding activity of CgCaspase-3 to different pathogen associated molecular patterns (PAMPs) and its effects on CgGSDME translocation in haemocytes were further investigated in C. gigas. The mRNA expression of CgCaspase-3 could be detected in all the tested tissues, including hepatopancreas, labial palp, adductor muscle, gonad, gill, mantle and haemocytes, and it was highly expressed in labial palp, gonad, haemocytes, and adductor muscle. The mRNA expression of CgCaspase-3 in haemocytes increased significantly at 3, 24, 48 and 72 h after LPS stimulation, and it increased significantly at 6, 12, 24 and 48 h after Vibrio splendidus stimulation. The recombinant CgCaspase-3 displayed binding activity towards LPS, mannose (MAN), peptidoglycan (PGN), and polyinosinic-polycytidylic acid potassium salt (Poly (I:C)). The positive signals of CgGSDME on haemocyte membrane became stronger at 3 h after V. splendidus stimulation, compared with that of Seawater group, and the co-localization of CgCaspase-3 and CgGSDME was observed in the haemocyte membrane. After the injection of dsCgCaspase-3, the positive signals of CgGSDME on haemocyte membrane became weaker compared with that of EGFP-RNAi group at 24 h after V. splendidus stimulation. The results suggested that CgCaspase-3 was able to bind diverse PAMPs and activate the translocation of CgGSDME in haemocytes of oyster response against pathogen invasion.

10.
Vaccines (Basel) ; 10(9)2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36146629

RESUMO

Oncolytic virotherapy has emerged as a novel form of cancer immunotherapy. Oncolytic viruses (OVs) can directly infect and lyse the tumor cells, and modulate the beneficial immune microenvironment. Vaccinia virus (VACV) is a promising oncolytic vector because of its high safety, easy gene editing, and tumor intrinsic selectivity. To further improve the safety, tumor-targeting ability, and OV-induced cancer-specific immune activation, various approaches have been used to modify OVs. The recombinant oncolytic VACVs with deleting viral virulence factors and/or arming various therapeutic genes have displayed better therapeutic effects in multiple tumor models. Moreover, the combination of OVs with other cancer immunotherapeutic approaches, such as immune checkpoint inhibitors and CAR-T cells, has the potential to improve the outcome in cancer patients. This will open up new possibilities for the application of OVs in cancer treatment, especially for personalized cancer therapies.

11.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077547

RESUMO

The BES1/BZR1 family is a plant-specific small group of transcription factors possessing a non-canonical bHLH domain. Genetic and biochemical analyses within the last two decades have demonstrated that members of this family are key transcription factors in regulating the expression of brassinosteroid (BR) response genes. Several recent genetic and evolutionary studies, however, have clearly indicated that the BES1/BZR1 family transcription factors also function in regulating several aspects of plant development via BR-independent pathways, suggesting they are not BR specific. In this review, we summarize our current understanding of this family of transcription factors, the mechanisms regulating their activities, DNA binding motifs, and target genes. We selectively discuss a number of their biological functions via BR-dependent and particularly independent pathways, which were recently revealed by loss-of-function genetic analyses. We also highlight a few possible future directions.


Assuntos
Proteínas de Arabidopsis , Brassinosteroides , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas , Desenvolvimento Vegetal/genética , Transdução de Sinais/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-36112793

RESUMO

Background: Gastric cancer is a common malignant tumor of the human digestive system. Currently, the treatment of gastric cancer is still dominated by radiotherapy, chemotherapy and surgery. Although the treatment is very effective, we are also trying to find new treatment methods. Traditional Chinese Medicine (TCM) may play an important role in the treatment of gastric cancer. Study Objective: The aim of this study is to explore the effects of naringin on the proliferation, migration, invasion and apoptosis of gastric cancer and its potential mechanisms. Methods: MGC803 and MKN45 viability were detected by MTT assay. The effects of naringin on cell cloning, migration and invasion were determined by colony formation assay, cell scratch test and transwell assay (ThermoFisher Scientific™, Waltham, Massachusetts USA), respectively. Cell cycle and apoptosis were assayed by flow cytometry. Associated proteins were measured using Western blot and immunohistochemistry (IHC). The experimental results were further verified in nude mice. Setting: This study was carried out in Department of Experimental Animal Center of Xi'an Jiaotong University and the Translation Medicine Center of the First Affiliated Hospital of Xi'an Jiaotong University in China. Results: Cells remained mainly in G0/G1 phase and apoptosis was increased. The nude mouse model showed that naringin treatment could inhibit the growth of tumors in nude mice. Cell scratch tests and transwell assay showed that the invasion and migration abilities of the gastric cancer cell line were significantly reduced after naringin treatment. Western blot showed that the expression of Vimentin, Zeb1 and P-AKT was downregulated and that E-cadherin was upregulated after naringin treatment. Conclusion: Naringin can block the cell-cycle, induce cancer cell apoptosis, and inhibit the epithelial mesenchymal transition (EMT) process by inhibiting the PI3K-AKT/Zeb1 pathway in gastric cancer cells. Therefore, naringin can inhibit the development of gastric cancer.

13.
Front Immunol ; 13: 944062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091003

RESUMO

Objective: To evaluate the efficacy and safety of sintilimab combined with apatinib plus capecitabine in the treatment of unresectable hepatocellular carcinoma (HCC) to provide a more effective first-line treatment for patients with advanced HCC. Methods: This open-label, prospective, phase II study included patients with unresectable HCC who did not receive systematic treatment. The patients were treated with sintilimab (200 mg, intravenous drip, once every 3 weeks) combined with apatinib (250 mg, oral administration, once a day) plus capecitabine (1000 mg/m2, twice a day; after 2 weeks of oral administration, the drug was stopped for 1 week; course of treatment, 3 weeks). The primary endpoint was the objective response rate (ORR). The secondary endpoints included disease control rate (DCR), progression-free survival (PFS), duration of response (DoR), overall survival (OS), and safety. Results: Forty-seven patients (1 lost to follow-up) were enrolled in the study. As of March 1, 2022, the ORR and DCR were 50.0% (95% CI: 34.9-65.1%) and 91.3% (95% CI: 79.2-97.6%), respectively, after blind, independent imaging evaluation. The median follow-up time was 18.7 months (95% CI: 17.2-20.2 months). The median PFS was 9.0 months (95% CI: 7.1-10.9 months). The median DoR was 10.8 months (95% CI: 4.8-16.8 months). The median OS was not reached, and the 1-year OS rate was 71.7% (95% CI: 56.5-84.0%). Only 28.3% (13/46) of patients had grade 3/4 treatment-related adverse events. Conclusion: Sintilimab combined with apatinib plus capecitabine has good safety and anti-tumor activity as a first-line treatment for unresectable HCC. This is worthy of further multi-center, prospective, randomized, large-sample clinical studies. Clinical Trial Registration: https://ClinicalTrials.gov, identifier NCT04411706.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Capecitabina/efeitos adversos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Estudos Prospectivos , Piridinas , Resultado do Tratamento
14.
ChemSusChem ; 15(21): e202201459, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36103362

RESUMO

Monoclinic Li3 V2 (PO4 )3 is a promising cathode material for high-power Li-ion batteries. Herein, a three-dimensional holey graphene enwrapped Li3 V2 (PO4 )3 /N-doped carbon (LVPNCHG) nanocomposite has been successfully synthesized. The holes could be in-situ and directly introduced in graphene through H2 O2 chemical etching in the synthesis process, which could remarkably enhance the ion and electron transport and greatly improve the electrochemical performance of the LVPNCHG electrode: 78 mAh g-1 at 150 C, 86.1 % capacity retention over 2000 cycles at 10 C, and 96 % capacity retention over 500 cycles at 1 C under -20 °C. Moreover, in-situ distribution of relaxation time analysis was used to study LVPNCHG cathode during charge/discharge at 3.0-4.8 V, combined with in-situ X-ray diffraction measurement, and the results showed that a two-phase reaction mechanism was involved during the insertion of Li+ in the discharge process. Further demonstration of graphite//LVPNCHG full cell indicated great potential of the as-synthesized materials for practical application.

15.
J Am Chem Soc ; 144(38): 17457-17467, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36102877

RESUMO

Here, we report the synthesis of two-dimensional (2D) layered metal-organic framework (MOF) nanoparticle (NP) superstructures via an ice-templating strategy. MOF NP monolayers and bilayers can be obtained by regulating the concentration of colloidal MOF NPs without any external fields during self-assembly. Adjacent polyhedral MOF NPs are packed and aligned through crystalline facets, resulting in the formation of a quasi-ordered array superstructure. The morphology of the MOF layers is well preserved when subjected to pyrolysis, and the obtained carbon NPs have hollow interiors driven by the outward contraction of MOF precursors during pyrolysis. With the advantages of large surface areas, hierarchical porosity, high exposure of active sites, and fast electron transport of the 2D layered structure, the mono- and bilayered carbon NP superstructures show better oxygen reduction activity than isolated carbon particles in alkaline media. Our work demonstrates that ice-templating is a powerful strategy to fabricate superstructures of various MOFs and their derivatives.

16.
J Immunother Cancer ; 10(9)2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36096529

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common malignant brain tumor with poor clinical outcomes. Immunotherapy has recently been an attractive and promising treatment of extracranial malignancies, however, most of clinical trials for GBM immunotherapy failed due to predominant accumulation of tumor-associated microglia/macrophages (TAMs). RESULTS: High level of LRIG2/soluble LRIG2 (sLRIG2) expression activates immune-related signaling pathways, which are associated with poor prognosis in GBM patients. LRIG2/sLRIGs promotes CD47 expression and facilitates TAM recruitment. Blockade of CD47-SIRPα interactions and inhibition of sLRIG2 secretion synergistically suppress GBM progression in an orthotropic murine GBM model. CONCLUSIONS: GBM cells with high level LRIG2 escape the phagocytosis by TAM via the CD47-SIRPα axis, highlighting a necessity for an early stage of clinical trial targeting LRIG2 and CD47-SIRPα as a novel treatment for patients with GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Neoplasias Encefálicas/patologia , Antígeno CD47/metabolismo , Humanos , Imunidade Inata , Macrófagos , Glicoproteínas de Membrana/metabolismo , Camundongos
17.
Nanoscale ; 14(39): 14630-14635, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36165071

RESUMO

Tubular structures offer a wide variety of applications; therefore, designing such materials with distinct dimensions is highly desirable yet challenging. In the current report, we have demonstrated the synthesis of a one-dimensional (1D) tubular assembly comprising porphyrin nanoring subunits. The porphyrin nanoring (PNR) 2 bearing ester groups was synthesized via Pt-mediated cyclization and then hydrolyzed to obtain PNR 3 with carboxylic groups. Under optimized conditions, porphyrin nanotubes (PNTs) were formed through hydrogen bonding between the carboxylic groups of 3. The morphology investigated by both SEM and TEM displayed well-defined arrays of nanotube bundles up to several micrometers long. Small crystals of PNTs were obtained by heating a solution of 3 in DMSO. High-resolution transmission electron microscopy (HR-TEM) accompanied by selected-area electron diffraction (SAED) exhibited a line of diffractions with d-spacing values of 6.17, 3.08, 2.07, and 1.57 Å. The miller indices of these diffractions could be assigned as 300, 600, 900, and 1200, respectively, suggesting that an ordered structure of 1D PNTs has been formed.

18.
Front Pharmacol ; 13: 960267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935817

RESUMO

Background: Similar pathogenesis makes Corona Virus Disease 2019 (COVID-19) associated with rheumatoid arthritis (RA), ankylosing spondylitis (AS) and gouty arthritis (GA), and it is possible to introduce common drugs for the treatment of RA, AS and GA into the treatment of COVID-19. That is, "homotherapy for heteropathy", especially cytokine inhibitors. But little is known about the specific link between the diseases. In addition, "new use of old drugs" is an important short-term strategy for the treatment of COVID-19. Cepharanthine (CEP), a monomer component of traditional Chinese medicine (TCM), is mainly used in the treatment of leukopenia and has recently been proved to have a good therapeutic effect on COVID-19, but its specific molecular mechanism has not been clearly explained. The purpose of this work is to explore the common targets and signaling pathways among COVID-19, RA, AS, and GA by means of network pharmacology (NP), and to infer the potential mechanism of CEP in the treatment of COVID-19. Methods: Firstly, SwissTargetPrediction was used to predict the targets of CEP, and the pathogenic targets of COVID-19, RA, AS and GA were searched in GeneCards, OMIM, TTD, PharmGKB database and literature, respectively. Then, the protein interaction network of CEP and COVID-19 cross targets and the common targets of COVID-19, RA, AS and GA was constructed. Cytosscape 3.7.2 software was used to construct CEP-common targets-signaling pathways-COVID-19 network, module function analysis, gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG). Finally, the molecular docking of hub targets and CEP was carried out by AutoDock software. Results: The results showed that the common targets of the four diseases were tumor necrosis factor (TNF), interleukin (IL)-6 and IL-1ß, and involved Coronavirus disease, IL-17 signaling pathway and TNF signaling pathway. CEP has a good binding force with AKT Serine/Threonine Kinase 1 (AKT1), phosphatidylinositol 3-kinase (PIK3) CA, PIK3CD and Angiotensin-converting enzyme 2 (ACE2), and plays a role in the treatment of COVID-19 by regulating PI3K-Akt signaling pathway, Relaxin signaling pathway, VEGF signaling pathway and HIF-1 signaling pathway. Conclusion: Therefore, this study not only confirmed the potential mechanism of CEP in the treatment of COVID-19 at the molecular level, but also found that TNF and IL-17 inhibitors, which are commonly used in the treatment of RA, AS and GA, may also affect the treatment of COVID-19, which provides new clues and theoretical basis for the rapid discovery of effective therapeutic drugs for COVID-19.

19.
J Am Chem Soc ; 144(36): 16559-16571, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35998652

RESUMO

Molecular geometry represents one of the most important structural features and governs physical properties and functions of materials. Nature creates a wide array of substances with distinct geometries but similar chemical composition with superior efficiency and precision. However, it remains a formidable challenge to construct abiological macromolecules with various geometries based on identical repeating units, owing to the lack of corresponding synthetic approaches for precisely manipulating the connectivity between monomers and feasible techniques for characterizing macromolecules at the single-molecule level. Herein, we design and synthesize a series of tetratopic monomers with chevron stripe shape which serve as the key precursors to produce four distinct types of metallo-macromolecules with well-defined geometries, viz., the concentric hexagon, helicoid polymer, ladder polymer, and cross-linked polymer, via platinum-acetylide couplings. Concentric hexagon, helicoid, and ladder metallo-polymers are directly visualized by transmission electron microscopy, atomic force microscopy, and ultra-high-vacuum low-temperature scanning tunneling microscopy at the single-molecule level. Finally, single-walled carbon nanotubes (SWCNTs) are selected as the guest to investigate the structure-property relationship based on such macromolecules, among which the helicoid metallo-polymer shows high efficiency in wrapping SWCNTs with geometry-dependent selectivity.


Assuntos
Nanotubos de Carbono , Polímeros , Substâncias Macromoleculares/química , Microscopia de Força Atômica , Nanotecnologia/métodos , Nanotubos de Carbono/química , Polímeros/química
20.
Angew Chem Int Ed Engl ; 61(39): e202209958, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35929987

RESUMO

The structures of the crosslinks in supramolecular polymer networks play an important role on their properties and functions. Herein, emissive metallacages are used as crosslinks to prepare metallacage-cored polyurethanes. The mechanical properties including storage modulus, toughness, Young's modulus and breaking strength of polymers are greatly enhanced with the increase of crosslinking densities. Moreover, such polymers not only exhibit good fluorescence in the solid state, but also show self-healing and shape memory properties owing to the dynamic reversible non-covalent bonds in their structures. This study not only offers a convenient strategy to prepare metallacage-crosslinked networks, but also explores their applications as self-healing and shape memory materials, which will promote the study of metallacage-cored supramolecular networks as smart materials.

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