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1.
Chem Rev ; 123(7): 3976-4050, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36990451

RESUMO

DNA nanotechnology is a unique field, where physics, chemistry, biology, mathematics, engineering, and materials science can elegantly converge. Since the original proposal of Nadrian Seeman, significant advances have been achieved in the past four decades. During this glory time, the DNA origami technique developed by Paul Rothemund further pushed the field forward with a vigorous momentum, fostering a plethora of concepts, models, methodologies, and applications that were not thought of before. This review focuses on the recent progress in DNA origami-engineered nanomaterials in the past five years, outlining the exciting achievements as well as the unexplored research avenues. We believe that the spirit and assets that Seeman left for scientists will continue to bring interdisciplinary innovations and useful applications to this field in the next decade.


Assuntos
Nanoestruturas , DNA , Nanotecnologia/métodos
2.
Nano Lett ; 24(20): 6102-6111, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739578

RESUMO

Acute lung injury (ALI) is a severe inflammatory lung disease, with high mortality rates. Early intervention by reactive oxygen species (ROS) scavengers could reduce ROS accumulation, break the inflammation expansion chain in alveolar macrophages (AMs), and avoid irreversible damage to alveolar epithelial and endothelial cells. Here, we reported cell-penetrating R9 peptide-modified triangular DNA origami nanostructures (tDONs-R9) as a novel nebulizable drug that could reach the deep alveolar regions and exhibit an enhanced uptake preference of macrophages. tDONs-R9 suppressed the expression of pro-inflammatory cytokines and drove polarization toward the anti-inflammatory M2 phenotype in macrophages. In the LPS-induced ALI mouse model, treatment with nebulized tDONs-R9 alleviated the overwhelming ROS, pro-inflammatory cytokines, and neutrophil infiltration in the lungs. Our study demonstrates that tDONs-R9 has the potential for ALI treatment, and the programmable DNA origami nanostructures provide a new drug delivery platform for pulmonary disease treatment with high delivery efficiency and biosecurity.


Assuntos
Lesão Pulmonar Aguda , DNA , Nanoestruturas , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Camundongos , DNA/química , Administração por Inalação , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Citocinas/metabolismo , Peptídeos/química , Nebulizadores e Vaporizadores , Peptídeos Penetradores de Células/química , Modelos Animais de Doenças , Lipopolissacarídeos , Sistemas de Liberação de Medicamentos , Células RAW 264.7
3.
Nano Lett ; 24(44): 13955-13964, 2024 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-39445643

RESUMO

A major challenge for stem cell therapies, such as using mesenchymal stem cells to treat skin injuries, is the stable engraftment of exogenous cells and the maintenance of their regenerative capacities in the wound areas. DNA-based self-assembly strategies can be used for artificial and multifunctional cell surface engineering to stabilize and enhance their functions for therapeutic applications. Here, we developed DNA nanofiber-decorated stem cells, in which DNA-based, multivalent fiber-like structures were self-assembled in situ on the cell surfaces. These engineered stem cells have demonstrated robust reactive oxygen species (ROS) scavenging effects, specific adhesion to damaged vascular endothelial cells, and the ability to enhance angiogenesis, which were effective and safe for acute or chronic wound healing in a mouse model with excisional skin injury. This DNA nanostructure-engineered stem cell provides a novel therapeutic platform for the treatment of tissue damage.


Assuntos
DNA , Células-Tronco Mesenquimais , Nanofibras , Cicatrização , Nanofibras/química , Animais , Células-Tronco Mesenquimais/citologia , Camundongos , DNA/química , Humanos , Espécies Reativas de Oxigênio/metabolismo , Engenharia Tecidual/métodos , Transplante de Células-Tronco Mesenquimais/métodos
4.
BMC Genomics ; 25(1): 354, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594645

RESUMO

The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.


Assuntos
Actinidia , Proteínas de Homeodomínio , Proteínas de Homeodomínio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Zíper de Leucina/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Perfilação da Expressão Gênica
5.
Anal Chem ; 96(11): 4623-4631, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38456770

RESUMO

Developing new electrochemiluminescence (ECL) luminators with high stability, wide applicability, and strong designability is of great strategic significance to promote the ECL field to the frontier. Here, driven by the I···N bond, 1,3,5-trifluoro-2,4,6-triiodobenzene (TFTI) and 2,4,6-trimethyl-1,3,5-triazine (TMT) self-assembled into a novel halogen cocrystal (TFTI-TMT) through slow solution volatilization. Significant difference of charge density existed between the N atoms on TMT and the σ-hole of the I atoms on TFTI. Upon the induction of σ-hole effect, high-speed and spontaneous charge transferring from TMT to the σ-hole of TFTI occurred, stimulating exciting ECL signals. Besides, the σ-hole of the I atoms could capture iodine ions specifically, which blocked the original charge transfer from the N atoms to the σ-hole, causing the ECL signal of TFTI-TMT to undergo a quenching rate as high as 92.9%. Excitingly, the ECL sensing of TFTI-TMT toward I- possessed a wide linear range (10-5000 nM) and ultralow detection limit (3 nM) in a real water sample. The halogen cocrystal strategy makes σ-hole a remarkable new viewpoint of ECL luminator design and enables ECL analysis technology to contribute to addressing the environmental and health threats posed by iodide pollution.

6.
Anal Chem ; 96(12): 5037-5045, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38477697

RESUMO

Uranium poses severe health risks due to its radioactivity and chemical toxicity if released into the environment. Therefore, there is an urgent demand to develop sensing materials in situ monitoring of uranium with high sensitivity and stability. In this work, a fluorescent Eu3+-TFPB-Bpy is synthesized by grafting Eu3+ cation onto TFPB-Bpy covalent organic framework (COF) synthesized through Schiff base condensation of monomers 1,3,5-tris(4-formylphenyl)benzene (TFPB) and 5,5'-diamino-2,2'-bipyridine (Bpy). The fluorescence of Eu3+-TFPB-Bpy is enhanced compared with that of TFPB-Bpy, which is originated from the intramolecular rotations of building blocks limited by the bipyridine units of TFPB-Bpy coordinated with Eu3+. More significantly, Eu3+-TFPB-Bpy is a highly efficient probe for sensing UO22+ in aqueous solution with the luminescence intensity efficiently amplified by complexation of UO22+ with Eu3+. The turn-on sensing capability was derived from the resonance energy transfer occurring from UO22+ to the Eu3+-TFPB-Bpy. The developed probe displayed desirable linear range from 5 nM to 5 µM with good selectivity and rapid response time (2 s) for UO22+ in mining wastewater. This strategy provides a vivid illustration for designing luminescence lanthanide COF hybrid materials with applications in environmental monitoring.

7.
Small ; 20(31): e2310241, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38441385

RESUMO

The direct use of mesenchymal stem cells (MSCs) as therapeutics for skin injuries is a promising approach, yet it still faces several obstacles, including limited adhesion, retention, and engraftment of stem cells in the wound area, as well as impaired regenerative and healing functions. Here, DNA-based self-assembled composites are reported that can aid the adhesion of MSCs in skin wounds, enhance MSC viability, and accelerate wound closure and re-epithelialization. Rolling-circle amplification (RCA)-derived DNA flowers, equipped with multiple copies of cyclic Arg-Gly-Asp (cRGD) peptides and anti-von Willebrand factor (vWF) aptamers, act as robust scavengers of reactive oxygen species (ROS) and enable synergistic recognition and adhesion to stem cells and damaged vascular endothelial cells. These DNA structure-aided stem cells are retained at localized wound sites, maintain repair function, and promote angiogenesis and growth factor secretion. In both normal and diabetes-prone db/db mice models with excisional skin injuries, facile topical administration of DNA flower-MSCs elicits rapid blood vessel formation and enhances the sealing of the wound edges in a single dose. DNA composite-engineered stem cells warrant further exploration as a new strategy for the treatment of skin and tissue damage.


Assuntos
DNA , Células-Tronco Mesenquimais , Pele , Cicatrização , Animais , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , DNA/metabolismo , Camundongos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos
8.
Small ; 20(25): e2310672, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229539

RESUMO

At present, poor stability and carrier transfer efficiency are the main problems that limit the development of perovskite-based photoelectric technologies. In this work, hydrogen-bonded cocrystal-coated perovskite composite (PeNCs@NHS-M) is easily obtained by inducing rapid crystallization of melamine (M) and N-hydroxysuccinimide (NHS) with PeNCs as the nuclei. The outer NHS-M cocrystal passivates the undercoordinated lead atoms by forming covalent bonds, thereby greatly reducing the trap density while maintaining good structure stability for perovskite nanocrystals. Moreover, benefiting from the interfacial covalent band linkage and long-range ordered structures of cocrystals, the charge transfer efficiency is effectively enhanced and PeNCs@NHS-M displays superior photoelectric performance. Based on the excellent photoelectric performance and abundant active sites of PeNCs@NHS-M, photocatalytic reduction of uranium is realized. PeNCs@NHS-M exhibits U(VI) reduction removal capability of up to 810.1 mg g-1 in the presence of light. The strategy of cocrystals trapping perovskite nanocrystals provides a simple synthesis method for composites and opens up a new idea for simultaneously improving the stability and photovoltaic performance of perovskite.

9.
Opt Lett ; 49(14): 4010-4013, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008764

RESUMO

Polarization singularities that exist in momentum space have brought new opportunities in various fields such as enhanced optical nonlinearity, structured laser sources, and light field manipulation. However, previous researches have predominantly focused on the polarization singularities above the light line, because they have no leakage and are referred to bound states in the continuum. Here, by extending the polarization fields to Fourier components of the evanescent field on a dielectric metasurface, polarization singularities of different Fourier orders are discovered below the light line. When continuously changing the geometrical parameters of the metasurface, a Fourier order transition process of the polarization singularity is observed through the bandgap closing at the boundary of the Brillouin zone, which finally leads to the annihilation of two singularities with opposite topological charges below the light line. These findings expand the understanding of polarization singularities in the near-field region and may find applications in light field manipulation and light-matter interaction.

10.
Inorg Chem ; 63(10): 4636-4645, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38394612

RESUMO

Two-dimensional (2D) metal-organic framework (MOF) nanosheets with large surface area, ultrathin thickness, and highly accessible active sites have attracted great research attention. Developing efficient approaches to realize the controllable synthesis of well-defined 2D MOFs with a specific composition and morphology is critical. However, it is still a significant challenge to construct thin and uniform 2D MOF nanosheets and resolve the reagglomeration as well as poor stability of target 2D MOF products. Here, an "in situ exfoliation growth" strategy is proposed, where a one-step synthetic process can realize the successful fabrication of PBA/MIL-53(NiFe)/NF nanosheets on the surface of nickel foam (NF) via in situ conversion and exfoliation growth strategies. The PBA/MIL-53(NiFe)/NF nanosheets combine the individual advantages of MOFs, Prussian blue analogues (PBAs), and 2D materials. As expected, the resulting PBA/MIL-53(NiFe)/NF as a glucose electrode exhibits an extremely high sensitivity of 25.74 mA mM-1 cm-2 in a very wide concentration range of 180 nM to 4.8 µM. The present exciting work provides a simple and effective strategy for the construction of high-performance nonenzymatic glucose electrochemical biosensors.

11.
Acta Pharmacol Sin ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992120

RESUMO

Fecal microbiota transplant (FMT) is becoming as a promising area of interest for treating refractory diseases. In this study, we investigated the effects of FMT on diabetes-associated cognitive defects in mice as well as the underlying mechanisms. Fecal microbiota was prepared from 8-week-aged healthy mice. Late-stage type 1 diabetics (T1D) mice with a 30-week history of streptozotocin-induced diabetics were treated with antibiotics for 7 days, and then were transplanted with bacterial suspension (100 µL, i.g.) once a day for 14 days. We found that FMT from healthy young mice significantly alleviated cognitive defects of late-stage T1D mice assessed in Morris water maze test. We revealed that FMT significantly reduced the relative abundance of Gram-negative bacteria in the gut microbiota and enhanced intestinal barrier integrity, mitigating LPS translocation into the bloodstream and NLRP3 inflammasome activation in the hippocampus, thereby reducing T1D-induced neuronal loss and astrocytic proliferation. FMT also reshaped the metabolic phenotypes in the hippocampus of T1D mice especially for alanine, aspartate and glutamate metabolism. Moreover, we showed that application of aspartate (0.1 mM) significantly inhibited NLRP3 inflammasome activation and IL-1ß production in BV2 cells under a HG/LPS condition. We conclude that FMT can effectively relieve T1D-associated cognitive decline via reducing the gut-brain metabolic disorders and neuroinflammation, providing a potential therapeutic approach for diabetes-related brain disorders in clinic.

12.
Surgeon ; 22(2): 99-106, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37872053

RESUMO

PURPOSE: Clarifying the prognosis and readmission patterns of patients with developmental dysplasia of the hip (DDH) following total hip arthroplasty (THA) would provide important references for clinical management for this population. Using the Chinese national inpatient database (i.e., Hospital Quality Monitoring System [HQMS]), we aimed to compare in-hospital complications and readmission patterns following THA in patients with DDH and primary osteoarthritis (OA). METHODS: Patients undergoing THA for DDH and OA between 2013 and 2019 were identified using the HQMS. Demographics and clinical characteristics were compared between the two groups. After propensity score matching, in-hospital complications and readmission patterns were compared using a logistic regression model. RESULTS: According to the analysis of 13,937 propensity-score matched pairs, there were no significant differences in the incidence of in-hospital death (0.01 % vs 0.04 %, P = 0.142), transfusion (8.09 % vs 7.89 %, P = 0.536), wound infection (0.31 % vs 0.25 %, P = 0.364), deep venous thrombosis (0.45 % vs 0.43 %, P = 0.786), pulmonary embolism (0.03 % vs 0.05 %, P = 0.372) or all-cause readmission (2.87 % vs 3.12 %, P = 0.219) between two groups. However, DDH patients had higher surgical readmission rates than OA patients (1.43 % vs 1.14 %, P = 0.033). When analyzing causes of surgical readmission, DDH patients had increased risk of dislocation (0.37 % vs 0.21 %, P = 0.011) and aseptic loosening (0.17 % vs 0.07 %, P = 0.024) than OA patients. CONCLUSION: DDH patients had an increased risk of surgical readmission following THA, mainly driven by dislocation and aseptic loosening, which should be recognized and appropriately prevented.


Assuntos
Artroplastia de Quadril , Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Readmissão do Paciente , Displasia do Desenvolvimento do Quadril/complicações , Displasia do Desenvolvimento do Quadril/cirurgia , Mortalidade Hospitalar , Luxação Congênita de Quadril/cirurgia , Resultado do Tratamento , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
13.
Arch Orthop Trauma Surg ; 144(1): 483-491, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37737901

RESUMO

INTRODUCTION: Decrease in allogenic red blood cell (RBC) transfusion rates following total hip arthroplasty (THA) has been reported in the United States, but whether other countries share the same trend remains unclear. Additionally, the relation of allogenic RBC transfusion to the risk of complications in THA remains controversial. Using the Chinese national inpatient database, the current study aimed to examine trends, complications, charges, and readmission patterns of allogeneic RBC transfusion in THA. MATERIALS AND METHODS: Patients undergoing primary THA between 2013 and 2019 were included, and then stratified into the transfusion and the non-transfusion group based on the database transfusion records. A generalized estimating equation model was used to investigate trends in transfusion rates. After propensity-score matching, a logistic regression model was used to compare the complications, rates and causes of 30-day readmission between two groups. RESULTS: A total of 10,270 patients with transfusion and 123,476 patients without transfusion were included. Transfusion rates decreased from 19.11% in 2013 to 9.94% in 2019 (P for trend < 0.001). After matching, no significant differences in the risk of of in-hospital death (odds ratio [OR], 4.00; 95% confidence interval [CI] 0.85-18.83), wound infection (OR 0.72; 95%CI 0.45-1.17), myocardial infarction (OR 1.17; 95%CI 0.62-2.19), deep vein thrombosis (OR 1.25; 95%CI 0.88-1.78), pulmonary embolism (OR 2.25; 95%CI 0.98-5.17), readmission rates (OR 1.07; 95%CI 0.88-1.30) and readmission causes were observed between two groups. However, the transfusion group had higher hospitalization charges than the non-transfusion group (72,239.89 vs 65,649.57 Chinese yuan [CNY], P < 0.001). CONCLUSIONS: This study found that allogeneic RBC transfusion in THA was not associated with the increased risk of complications and any-cause readmission. However, the currently restrictive transfusion policy should be continued because excessive blood transfusion may increase the socioeconomic burden.


Assuntos
Artroplastia de Quadril , Transplante de Células-Tronco Hematopoéticas , Humanos , Estados Unidos , Artroplastia de Quadril/efeitos adversos , Transfusão de Eritrócitos/efeitos adversos , Estudos Retrospectivos , Readmissão do Paciente , Mortalidade Hospitalar , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
14.
Anal Chem ; 95(28): 10803-10811, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37401846

RESUMO

The structural isomerism of the covalent organic framework (COF) has a significant effect on the electrochemiluminescence (ECL) performance. Herein, we report a pair of isomeric COFs, (TFPB-BD(OMe)2-H and TAPB-BD(OMe)2-H), based on the different directions of imine linkages and further conversion of the imine to the quinoline structure. The obtained two isomeric COFs with the same composition and similar structures exhibit dramatic differences in the photoelectrochemical and ECL fields. Indeed, TFPB-BD(OMe)2-H demonstrates robust ECL emission superior to that of TAPB-BD(OMe)2-H. The difference in ECL performance is due to the stronger polar interaction of TFPB-BD(OMe)2-H than that of TAPB-BD(OMe)2-H. The polarity is derived from the uneven charge distribution within the framework and enhances the electron interactions. In addition, the ordered conjugate skeleton provides high-speed charge transport channels for carrier transport. Therefore, the TFPB-BD(OMe)2-H presents a smaller band gap energy and stronger polarization interaction, which are more favorable to charge migration to achieve stronger ECL signals. Furthermore, we describe a convenient ECL sensor for detecting toxic As(V) with an outstanding detection property and ultralow detection limit. This work provides a guiding principle for the design and development of ECL organic luminophores.

15.
Anal Chem ; 95(22): 8696-8705, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37224420

RESUMO

The application of covalent organic frameworks (COFs) in electrochemiluminescence (ECL) is promising in environmental monitoring. Developing an emerging design strategy to expand the class of COF-based ECL luminophores is highly desirable. Here, a COF-based host-guest system was constructed through guest molecular assembly to deal with nuclear contamination analysis. The efficient charge transport network was formed by inserting an electron-withdrawing guest tetracyanoquinodimethane (TCNQ) into the open space of the COF host (TP-TBDA; TP = 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and TBDA = 2,5-di(thiophen-2-yl)benzene-1,4-diamine) with an electron-donating property; the construction of the COF-based host-guest system (TP-TBDA@TCNQ) triggered the ECL emission of non-emitting TP-TBDA. Furthermore, the dense active sites in TP-TBDA were utilized to capture the target substance UO22+. The presence of UO22+ broke the charge-transfer effect in TP-TBDA@TCNQ, resulting in the weakening of the ECL signal, thus the established ECL system integrating the low detection limit with high selectivity monitors UO22+. This COF-based host-guest system provides a novel material platform for constructing late-model ECL luminophores and creates an opportunity for the vigorous ECL technology.

16.
Small ; 19(39): e2302254, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236205

RESUMO

Covalent organic frameworks (COFs) show potentials in prominent photoelectric responses by judicious structural design. However, from the selections of monomers and condensation reactions to the synthesis procedures, the acquisition of photoelectric COFs has to meet overmuch high conditions, limiting the breakthrough and modulation in photoelectric responses. Herein, the study reports a creative "lock-key model" based on molecular insertion strategy. A COF with suitable cavity size, TP-TBDA, is used as the host to load guests. Merely through the volatilization of mixed solution, TP-TBDA and guests can be spontaneously assembled via non-covalent interactions (NCIs) to produce molecular-inserted COFs (MI-COFs). The NCIs between TP-TBDA and guests acted as a bridge to facilitate charge transfer in MI-COFs, unlocking the photoelectric responses of TP-TBDA. By exploiting the controllability of NCIs, the MI-COFs can realize the smart modulation of photoelectric responses by simply changing the guest molecule, thus avoiding the arduous selection of monomers and condensation reactions required by conventional COFs. The construction of molecular-inserted COFs circumvents complicated procedures for achieving performance improvement and modulation, providing a promising direction to construct late-model photoelectric responsive materials.

17.
Opt Lett ; 48(4): 920-923, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36790975

RESUMO

Optical beams with a pure longitudinally polarized field are of great interest for their unique properties and promising applications in various fields such as optical trapping and three-dimensional microscopy. Here, an all-dielectric metasurface is proposed to directly generate Bessel beams with tunable longitudinally polarized electric and magnetic fields under a simple incidence of linear polarization. Under the incidence of horizontal polarization, a Bessel beam with a pure longitudinally polarized electric field can be generated, which can be turned to a beam with a pure longitudinally polarized magnetic field when the incidence is switched to vertical polarization. More importantly, it is further demonstrated that the longitudinal components of the electric and magnetic fields can be accurately manipulated between zero and the maximum by simply changing the polarization angle of incident light. The simplicity and flexibility of this proposed metasurface may provide new possibilities in ultracompact photonic devices for optical trapping, optical storage, and related fields.

18.
Phys Rev Lett ; 131(1): 013801, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478422

RESUMO

Polarization singularities including bound states in the continuum (BICs) and circularly polarized states have provided promising opportunities in the manipulation of light waves. Previous studies show that BICs in photonic crystal slabs are protected by C_{2}T symmetry and hence normally exist on the high-symmetry lines of momentum space. Here, we propose an approach based on graph theory to study these polarization singularities in momentum space, especially in the region off the high-symmetry lines. With a polarization graph, it is demonstrated for the first time that BICs can stably exist off the high-symmetry lines of momentum space for both one-dimensional and two-dimensional photonic crystal slabs. Furthermore, two kinds of interesting processes, including the merging involved with this newly found BICs both on and off the high-symmetry lines, are observed by changing the geometrical parameters of photonic crystal slabs while keeping their symmetry. Our findings provide a new perspective to explore polarization singularities in momentum space and render their further applications in light-matter interaction and light manipulation.

19.
Crit Rev Food Sci Nutr ; : 1-21, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37548408

RESUMO

Extracellular vesicles (EVs) are naturally occurring non-replicating particles released from cells, known for their health-promoting effects and potential as carriers for drug delivery. Extensive research has been conducted on delivery systems based on culture-cell-derived EVs. Nevertheless, they have several limitations including low production yield, high expenses, unsuitability for oral administration, and safety concerns in applications. Conversely, food-derived EVs (FDEVs) offer unique advantages that cannot be easily substituted. This review provides a comprehensive analysis of the biogenesis pathways, composition, and health benefits of FDEVs, as well as the techniques required for constructing oral delivery systems. Furthermore, it explores the advantages and challenges associated with FDEVs as oral nanocarriers, and discusses the current research advancements in delivering active phytoconstituents. FDEVs, functioning as a nanocarrier platform for the oral delivery of active molecules, present numerous benefits such as convenient administration, high biocompatibility, low toxicity, and inherent targeting. Nevertheless, numerous unresolved issues persist in the isolation, characterization, drug loading, and application of FDEVs. Technical innovation and standardization of quality control are the key points to promote the development of FDEVs. The review aimed to provide frontier ideas and basic quality control guidelines for developing new functional food based on FDEVs oral drug delivery system.


Extracellular vesicles (EVs) are excellent nano-carriers for active molecules.Food-derived EVs (FDEVs) are better sources of EVs in delivery applications.Active phytoconstituents could be protected by loading them into FDEVs.The development of FDEVs-based delivery system is promising in new functional food.

20.
Crit Rev Food Sci Nutr ; 63(22): 5953-5966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35057688

RESUMO

Potential roles for anthocyanins in preventing various chronic diseases have been reported. These compounds are highly sensitive to external conditions and are susceptible to degradation, which increases the complexity of their metabolism in vivo. This review discusses anthocyanin metabolism in the digestive tract, phase I and II metabolism, and enterohepatic circulation (EHC), as well as their distribution of anthocyanins in blood, urine, and several organs. In the oral cavity, anthocyanins are partly hydrolyzed by microbiota into aglycones which are then conjugated by glucuronidase. In stomach, anthocyanins are absorbed without deglycosylation via specific transporters, such as sodium-dependent glucose co-transporter 1 and facilitative glucose transporters 1, while in small intestine, they are mainly absorbed as aglycones. High polymeric anthocyanins are easily degraded into low-polymeric forms or smaller phenolic acids by colonic microbiota, which improves their absorption. Anthocyanins and their derivatives are modified by phase I and II metabolic enzymes in cells and are released into the blood via the gastrovascular cavity into EHC. Notably, interconversion can be occurred under the action of enzymes such as catechol-O-methyltransferase. Taking together, differences in anthocyanin absorption, distribution, metabolism, and excretion largely depend on their glycoside and aglycone structures.


Assuntos
Antocianinas , Catecol O-Metiltransferase , Antocianinas/metabolismo , Trato Gastrointestinal/metabolismo , Intestino Delgado/metabolismo , Glucose
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