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1.
Nat Immunol ; 25(2): 307-315, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182667

RESUMO

The global outbreak of the mpox virus (MPXV) in 2022 highlights the urgent need for safer and more accessible new-generation vaccines. Here, we used a structure-guided multi-antigen fusion strategy to design a 'two-in-one' immunogen based on the single-chain dimeric MPXV extracellular enveloped virus antigen A35 bivalently fused with the intracellular mature virus antigen M1, called DAM. DAM preserved the natural epitope configuration of both components and showed stronger A35-specific and M1-specific antibody responses and in vivo protective efficacy against vaccinia virus (VACV) compared to co-immunization strategies. The MPXV-specific neutralizing antibodies elicited by DAM were 28 times higher than those induced by live VACV vaccine. Aluminum-adjuvanted DAM vaccines protected mice from a lethal VACV challenge with a safety profile, and pilot-scale production confirmed the high yield and purity of DAM. Thus, our study provides innovative insights and an immunogen candidate for the development of alternative vaccines against MPXV and other orthopoxviruses.


Assuntos
Monkeypox virus , Vacinas , Animais , Camundongos , Proteínas do Envelope Viral , Anticorpos Antivirais , Vaccinia virus , Antígenos Virais , Imunidade
3.
Nano Lett ; 24(1): 16-25, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38109350

RESUMO

The anomalous Hall effect (AHE) is an important transport signature revealing topological properties of magnetic materials and their spin textures. Recently, MnBi2Te4 has been demonstrated to be an intrinsic magnetic topological insulator. However, the origin of its intriguing AHE behaviors remains elusive. Here, we demonstrate the Berry curvature-dominated intrinsic AHE in wafer-scale MnBi2Te4 films. By applying back-gate voltages, we observe an ambipolar conduction and n-p transition in ∼7-layer MnBi2Te4, where a quadratic relation between the AHE resistance and longitudinal resistance suggests its intrinsic AHE nature. In particular, for ∼3-layer MnBi2Te4, the AHE sign can be tuned from pristine negative to positive. First-principles calculations unveil that such an AHE reversal originated from the competing Berry curvature between oppositely polarized spin-minority-dominated surface states and spin-majority-dominated inner bands. Our results shed light on the underlying physical mechanism of the intrinsic AHE and provide new perspectives for the unconventional sign-tunable AHE.

4.
Nano Lett ; 24(17): 5125-5131, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639405

RESUMO

We report a study of thickness-dependent interband and intraband magnetic breakdown by thermoelectric quantum oscillations in ZrSiSe nanoplates. Under high magnetic fields of up to 30 T, quantum oscillations arising from degenerated hole pockets were observed in thick ZrSiSe nanoplates. However, when decreasing the thickness, plentiful multifrequency quantum oscillations originating from hole and electron pockets are captured. These multiple frequencies can be explained by the emergent interband magnetic breakdown enclosing individual hole and electron pockets and intraband magnetic breakdown within spin-orbit coupling (SOC) induced saddle-shaped electron pockets, resulting in the enhanced contribution to thermal transport in thin ZrSiSe nanoplates. These experimental frequencies agree well with theoretical calculations of the intriguing tunneling processes. Our results introduce a new member of magnetic breakdown to the field and open up a dimension for modulating magnetic breakdown, which holds fundamental significance for both low-dimensional topological materials and the physics of magnetic breakdown.

5.
J Cell Mol Med ; 28(13): e18510, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38953409

RESUMO

In recent years, inflammatory disorders have emerged as a significant concern for human health. Through ongoing research on anti-inflammatory agents, alpinetin has shown promising anti-inflammatory properties, including involvement in epigenetic modification pathways. As a crucial regulator of epigenetic modifications, Mecp2 may play a role in modulating the epigenetic effects of alpinetin, potentially impacting its anti-inflammatory properties. To test this hypothesis, two key components, p65 (a member of NF-KB family) and p300 (a type of co-activator), were screened by the expression profiling microarray, which exhibited a strong correlation with the intensity of LPS stimulation in mouse macrophages. Meanwhile, alpinetin demonstrates the anti-inflammatory properties through its ability to disrupt the synthesis of p65 and its interaction with promoters of inflammatory genes, yet it did not exhibit similar effects on p300. Additionally, Mecp2 can inhibit the binding of p300 by attaching to the methylated inflammatory gene promoter induced by alpinetin, leading to obstacles in promoter acetylation and subsequently impacting the binding of p65, ultimately enhancing the anti-inflammatory capabilities of alpinetin. Similarly, in a sepsis mouse model, it was observed that homozygotes overexpressing Mecp2 showed a greater reduction in organ damage and improved survival rates compared to heterozygotes when administered by alpinetin. However, blocking the expression of DNA methyltransferase 3A (DNMT3A) resulted in the loss of Mecp2's anti-inflammatory assistance. In conclusion, Mecp2 may augment the anti-inflammatory effects of alpinetin through epigenetic 'crosstalk', highlighting the potential efficacy of a combined therapeutic strategy involving Mecp2 and alpinetin for anti-inflammatory intervention.


Assuntos
Anti-Inflamatórios , Epigênese Genética , Flavanonas , Proteína 2 de Ligação a Metil-CpG , Regiões Promotoras Genéticas , Proteína 2 de Ligação a Metil-CpG/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Animais , Flavanonas/farmacologia , Epigênese Genética/efeitos dos fármacos , Camundongos , Anti-Inflamatórios/farmacologia , Células RAW 264.7 , Metilação de DNA/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fator de Transcrição RelA/metabolismo , Sepse/tratamento farmacológico , Sepse/genética , Sepse/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Inflamação/genética , Inflamação/metabolismo , DNA Metiltransferase 3A/metabolismo , Masculino , Proteína p300 Associada a E1A/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética
6.
Phys Rev Lett ; 132(11): 110201, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38563920

RESUMO

We propose a solvable model of quantum Darwinism to encoding transitions-abrupt changes in how quantum information spreads in a many-body system under unitary dynamics. We consider a random Clifford circuit on an expanding tree, whose input qubit is entangled with a reference. The model has a quantum Darwinism phase, where one classical bit of information about the reference can be retrieved from an arbitrarily small fraction of the output qubits, and an encoding phase where such retrieval is impossible. The two phases are separated by a mixed phase and two continuous transitions. We compare the exact result to a two-replica calculation. The latter yields a similar "annealed" phase diagram, which applies also to a model with Haar random unitaries. We relate our approach to measurement-induced phase transitions (MIPTs), by solving a modified model where an environment eavesdrops on an encoding system. It has a sharp MIPT only with full access to the environment.

7.
Phys Chem Chem Phys ; 26(19): 14194-14204, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38713135

RESUMO

Constructing Z-scheme heterojunctions incorporating an exquisite hollow structure is an effective performance regulation strategy for the realization of high quantum efficiency and a strong redox ability over photocatalysts. Herein, we report the delicate design and preparation of a core-shell hollow CdS@CoTiO3 Z-scheme heterojunction with a CdS nanoparticle (NP)-constructed outer shell supported on a CoTiO3 nanorod (NR) inner shell. The in situ growth synthetic method led to a tightly connected interface for the heterojunction between CdS and CoTiO3, which shortened the transport distance of photoinduced charges from the interface to the surface. The promoted charge carrier separation efficiency and the retained strong redox capacity caused by the Z-scheme photoinduced charge-transfer mechanism were mainly responsible for the boosted photocatalytic performance. Additionally, the well-designed core-shell structure afforded a larger interfacial area by the multiple direction contact between CdS and CoTiO3, ensuring sufficient channels for efficient charge transfer, and thus further boosting the photocatalytic activity. As an efficient photocatalyst, the optimized CdS@CoTiO3 nanohybrids displayed excellent 2,4-dichlorophenol (2,4-DCP) and tetracycline (TC) degradation efficiencies of 91.3% and 91.8%, respectively. This study presents a Z-scheme heterojunction based on ecofriendly CoTiO3, which could be valuable for the development of metal perovskite photocatalysts for application in environmental remediation, and also demonstrated the tremendous potential of integrating a Z-scheme heterojunction with the morphology design of photocatalyts.

8.
Environ Res ; 251(Pt 1): 118534, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38395336

RESUMO

TatD DNase, a key enzyme in vertebrates and invertebrates, plays a pivotal role in various physiological processes. Dugesia japonica (D. japonica), a flatworm species, has remarkable regenerative capabilities and possesses a simplified immune system. However, the existence and biological functions of TatD DNase in D. japonica require further investigation. Here, we obtained the open reading frame (ORF) of DjTatD and demonstrated its conservation. The three-dimensional structure of DjTatD revealed its active site and binding mechanism. To investigate its enzymological properties, we overexpressed, purified, and characterized recombinant DjTatD (rDjTatD). We observed that DjTatD was primarily expressed in the pharynx and its expression could be significantly challenged upon stimulation with lipopolysaccharide, peptidoglycan, gram-positive and gram-negative bacteria. RNA interference results indicated that both DjTatD and DjDN2s play a role in pharyngeal regeneration and may serve as functional complements to each other. Additionally, we found that rDjTatD and recombinant T7DjTatD effectively reduce biofilm formation regardless of their bacterial origin. Together, our results demonstrated that DjTatD may be involved in the planarian immune response and pharyngeal regeneration. Furthermore, after further optimization in the future, rDjTatD and T7DjTatD can be considered highly effective antibiofilm agents.


Assuntos
Biofilmes , Desoxirribonucleases , Planárias , Animais , Planárias/genética , Planárias/fisiologia , Planárias/enzimologia , Biofilmes/efeitos dos fármacos , Desoxirribonucleases/metabolismo , Desoxirribonucleases/genética , Desoxirribonucleases/química , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Proteínas de Helminto/química , Proteínas de Helminto/farmacologia , Sequência de Aminoácidos
9.
Int J Sports Med ; 45(2): 85-94, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37820692

RESUMO

To identify factors associated with subscapularis (SSC) tears and provide a theoretical basis for clinical diagnosis, we included studies related to subscapularis tears published before February 1, 2023. We screened for six predictors across previous studies for the meta-analysis. The predictors included age, sex, coracoid overlap (CO), coracohumeral distance (CHD), impairment of the long head of the biceps tendon (LHB), and dominant arm. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. The risk ratios (RRs) and the weighted mean differences (WMDs) were used to evaluate the effect size of categorical variables and continuous variables, respectively. The Egger test was used to assess the publication bias of the studies. Ten studies were included from seven countries. A total of 2 126 patients were enrolled, of whom 1 041 had subscapularis tears and 1 085 did not. The study showed that age (WMD, 4.23 [95% CI, 2.32-6.15]; P<.00001), coracoid overlap (WMD, 1.98 [95% CI, 1.55-2.41]; P<.00001), coracohumeral distance(WMD, -1.03 [95% CI, -1.17- -0.88]; P<.00001), and an injury of the long head of the biceps tendon (RR, 4.98 [95% CI, 3.75-6.61]; P<.00001) were risk factors for subscapularis tears. These risk factors can help clinicians identify subscapularis tears early and select appropriate interventions. The level of evidence is 3.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Humanos , Lesões do Manguito Rotador/diagnóstico , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Ruptura , Artroscopia
10.
Nano Lett ; 23(19): 9026-9033, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37767914

RESUMO

The quantum Hall effect is one of the exclusive properties displayed by Dirac Fermions in topological insulators, which propagates along the chiral edge state and gives rise to quantized electron transport. However, the quantum Hall effect formed by the nondegenerate Dirac surface states has been elusive so far. Here, we demonstrate the nondegenerate integer quantum Hall effect from the topological surface states in three-dimensional (3D) topological insulator ß-Ag2Te nanostructures. Surface-state dominant conductance renders quantum Hall conductance plateaus with a step of e2/h, along with typical thermopower behaviors of two-dimensional (2D) massless Dirac electrons. The 2D nature of the topological surface states is proven by the electrical and thermal transport responses under tilted magnetic fields. Moreover, the degeneracy of the surface states is removed by structure inversion asymmetry (SIA). The evidenced SIA-induced nondegenerate integer quantum Hall effect in low-symmetry ß-Ag2Te has implications for both fundamental study and the realization of topological magneto-electric effects.

11.
Environ Geochem Health ; 46(6): 197, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696118

RESUMO

Micro/nanoplastics (MNPs) are emerging as environmental pollutants with potential threats to human health. The accumulation of MNPs in the body can cause oxidative stress and increase the risk of cardiovascular disease (CVD). With the aim to systematically evaluate the extent of MNPs-induced oxidative damage and serum biochemical parameters in rats and mice, a total of 36 eligible articles were included in this meta-analysis study. The results reported that MNPs can significantly increase the levels of oxidants such as reactive oxygen species (ROS) and malondialdehyde (MDA) (P < 0.05), and resulted in notable increase in serum biochemical parameters including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (P < 0.05). Conversely, MNPs significantly reduced levels of antioxidants such as superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT) (P < 0.05). Subgroup analysis revealed that smaller MNPs with oral administration and prolonged treatment, were associated with more pronounced oxidative stress and enhanced serum biochemical parameters alteration. In addition, after affected by MNPs, the levels of ALT and AST in liver group (SMD = 2.26, 95% CI = [1.59, 2.94] and SMD = 3.10, 95% CI = [1.25, 4.94]) were higher than those in other organs. These comprehensive results provide a scientific foundation for devising strategies to prevent MNPs-induced damage, contributing to solution of this environmental and health challenge.


Assuntos
Estresse Oxidativo , Animais , Camundongos , Ratos , Alanina Transaminase/sangue , Antioxidantes/metabolismo , Aspartato Aminotransferases/sangue , Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Malondialdeído/sangue , Microplásticos/toxicidade , Nanopartículas , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
12.
J Mol Recognit ; 36(8): e3046, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37455320

RESUMO

As a natural carrier protein, zein was intensively studied for the construction of a flavonoid delivery system. Chrysin has presented superior tumor-resistant, anti-inflammatory, and anti-oxidation potentials among the flavonoid candidates in clinical practice. However, due to inadequate research, the binding mechanism and structural affinity of zein to chrysin are still indeterminate. Therefore, multispectral methods were employed to explore the molecular interaction of zein and chrysin in this work. These techniques showed that chrysin reduced the intrinsic fluorescence of zein via a static process and that the interaction between zein and chrysin was mainly driven spontaneously by hydrophobic forces. Additionally, the experimental results revealed the changed microenvironment in the vicinity of tyrosine and affected secondary structure in the presence of chrysin, indicating zein's conformation were altered by chrysin. This work provided comprehensive insight into the combination of plant-derived protein (zein) and flavonoids (chrysin) and helped rationalize the protection, transportation, and release of chrysin through a zein-based delivery system.


Assuntos
Zeína , Zeína/química , Flavonoides/química
13.
Opt Express ; 31(21): 35086-35099, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859248

RESUMO

Metasurfaces have shown extraordinary capability in individually manipulating various electromagnetic (EM) properties, including polarization, phase, and amplitude. However, it is still a challenge to manipulate these EM properties in one metasurface simultaneously. In this paper, a programmable multifunctional metasurface (PMFMS) is demonstrated with polarization, phase, and amplitude manipulation abilities. By controlling tunable coding states and changing the direction of incident waves, the PMFMS can operate as a transmission cross-polarization converter, spatial wave manipulator, and low-RCS radome. Besides, the PMFMS possesses an ultra-wideband property, which can operate from 6.5 to 10.2 GHz with 44.3% relative bandwidth. More importantly, multiple functionalities can also be achieved in reflection operating mode by reassembling the PMFMS. As a proof of concept, the PMFMS is fabricated and experimentally verified. Measured results are in good agreement with simulated results. Benefiting from multifunctional EM manipulations in an ultra-wideband, such a design can be applied in wireless communication systems, radar detection, and EM stealth platform.

14.
Opt Express ; 31(10): 16471-16483, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157725

RESUMO

Electronically reconfigurable transmitarray (ERTA) combines the advantages of optic theory and coding metasurface mechanism with the characteristic of low-loss spatial feed and real-time beam manipulation. Designing a dual-band ERTA is challenging due to multiple factors, including large mutual coupling generated by dual-band operation and separate phase control in each band. In this paper, a dual-band ERTA is demonstrated with the capability of fully independent beam manipulation in two divided bands. This dual-band ERTA is constructed by two kinds of orthogonally polarized reconfigurable elements which share the aperture in an interleaved way. The low coupling is achieved by utilizing polarization isolation and a backed cavity connected to the ground. To separately control the 1-bit phase in each band, a hierarchical bias method is elaborately presented. As proof of concept, a dual-band ERTA prototype composed of 15 × 15 upper-band elements and 16 × 16 lower-band elements is designed, fabricated, and measured. Experimental results verify that fully independent beam manipulation with orthogonal polarization is implemented in 8.2-8.8 GHz and 11.1-11.4 GHz. The proposed dual-band ERTA may be a suitable candidate for space-based synthetic aperture radar imaging.

15.
Inorg Chem ; 62(11): 4485-4494, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36893304

RESUMO

A novel sulfur-bridged metal-organic framework (MOF) [Co(TIC4R-I)0.25Cl2]·3CH3OH (Co-TIC4R-I) based on thiacalix[4]arene derivatives was successfully obtained using a solvothermal method. Remarkably, adjacent TIC4R-I ligands were linked via Co(II) cations to form a three-dimensional (3D) microporous architecture. Subsequently, Co-TIC4R-I was modified on a glassy carbon electrode (Co-TIC4R-I/GCE) to produce an electrochemical sensor for the detection of heavy-metal ions (HMIs), namely, Cd2+, Pb2+, Cu2+, and Hg2+, in aqueous solutions. It was found that Co-TIC4R-I/GCE exhibited wide linear detection ranges of 0.10-17.00, 0.05-16.00, 0.05-10.00, and 0.80-15.00 µM for Cd2+, Pb2+, Cu2+, and Hg2+, respectively, in addition to low limit of detection (LOD) values of 0.017, 0.008, 0.016, and 0.007 µM. Moreover, the fabricated sensor employed for the simultaneous detection of these metals has achieved LOD values of 0.0067, 0.0027, 0.0064, and 0.0037 µM for Cd2+, Pb2+, Cu2+, and Hg2+, respectively. The sensor also exhibited satisfactory selectivity, reproducibility, and stability. Furthermore, the relative standard deviation (RSD) values of Cd2+, Pb2+, Cu2+, and Hg2+ were 3.29, 3.73, 3.11, and 1.97%, respectively. Moreover, the fabricated sensor could sensitively detect HMIs in various environmental samples. The high performance of the sensor was attributed to its sulfur adsorption sites and abundant phenyl rings. Overall, the sensor described herein provides an efficient method for the determination of extremely low concentrations of HMIs in aqueous samples.

16.
BMC Plant Biol ; 22(1): 488, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36229795

RESUMO

BACKGROUND: N-acyl-homoserine lactones (AHLs) are used as quorum-sensing signals by Gram-negative bacteria, but they can also affect plant growth and disease resistance. N-decanoyl-L-homoserine lactone (C10-HSL) is an AHL that has been shown to inhibit primary root growth in Arabidopsis, but the mechanisms underlying its effects on root architecture are unclear. Here, we investigated the signaling components involved in C10-HSL-mediated inhibition of primary root growth in Arabidopsis, and their interplay, using pharmacological, physiological, and genetic approaches. RESULTS: Treatment with C10-HSL triggered a transient and immediate increase in the concentrations of cytosolic free Ca2+ and reactive oxygen species (ROS), increased the activity of mitogen-activated protein kinase 6 (MPK6), and induced nitric oxide (NO) production in Arabidopsis roots. Inhibitors of Ca2+ channels significantly alleviated the inhibitory effect of C10-HSL on primary root growth and reduced the amounts of ROS and NO generated in response to C10-HSL. Inhibition or scavenging of ROS and NO neutralized the inhibitory effect of C10-HSL on primary root growth. In terms of primary root growth, the respiratory burst oxidase homolog mutants and a NO synthase mutant were less sensitive to C10-HSL than wild type. Activation of MPKs, especially MPK6, was required for C10-HSL to inhibit primary root growth. The mpk6 mutant showed reduced sensitivity of primary root growth to C10-HSL, suggesting that MPK6 plays a key role in the inhibition of primary root growth by C10-HSL. CONCLUSION: Our results indicate that MPK6 acts downstream of ROS and upstream of NO in the response to C10-HSL. Our data also suggest that Ca2+, ROS, MPK6, and NO are all involved in the response to C10-HSL, and may participate in the cascade leading to C10-HSL-inhibited primary root growth in Arabidopsis.


Assuntos
Arabidopsis , 4-Butirolactona/análogos & derivados , Acil-Butirolactonas/farmacologia , Bactérias , Proteína Quinase 6 Ativada por Mitógeno , Óxido Nítrico/farmacologia , Percepção de Quorum , Espécies Reativas de Oxigênio
17.
J Mol Recognit ; 35(12): e2985, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35907782

RESUMO

Gout is an inflammatory joint disease caused by urate crystal deposition, which is associated with hyperuricemia. Gout will take place when the uric acid accumulates. Xanthine oxidase (XO) is a crucial enzyme in the formation of uric acid. Inhibiting XO is one of the means to ameliorate gout. Luteoloside is a kind of natural flavonoid, which has an excellent prospect for relieving gout. But there are few reports on the interaction mechanism between luteoloside and XO currently. In this study, the interaction mechanism between luteoloside and XO was explored using spectroscopy and molecular docking. The fluorescence spectroscopy results indicated that luteoloside could make the intrinsic fluorescence of XO quenched, and the binding constant between luteoloside and XO was (1.85 ± 0.22) × 103 L mol-1 at 298 K. The synchronous fluorescence spectroscopy results showed that the absorption peaks of Tyr and Trp shifted blue, and the hydrophobicity of the microenvironment increased. Moreover, CD spectra showed that α-helix of XO decreased, ß-sheet and ß-turn increased after adding luteoloside. The results of molecular docking analysis showed that XO could combine with luteoloside through hydrogen bonds and hydrophobic force. The results indicated that luteoloside could remarkably interact with XO. Insights into the interaction mechanism provide a necessary basis for the search for low-toxic natural products as targets of XO. HIGHLIGHTS: Luteoloside and xanthine oxidase was a strong binding mode and had only one binding site. Luteoloside could cause α-helix reduced, ß-sheet and ß-turn increased, and change the secondary structure of XO. The binding between luteoloside and xanthine oxidase was a spontaneous process. The main binding force was hydrophobic force between luteoloside and xanthine oxidase.


Assuntos
Gota , Xantina Oxidase , Humanos , Xantina Oxidase/química , Xantina Oxidase/metabolismo , Simulação de Acoplamento Molecular , Ácido Úrico , Inibidores Enzimáticos/farmacologia , Espectrometria de Fluorescência
18.
J Mol Recognit ; 35(2): e2946, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34918387

RESUMO

It is an effective strategy to avoid obesity by inhibiting the activity of lipase. In this study, the binding mechanism of lipase and Lentinus edodes mycelia polysaccharide (LMP) were explored with multi-spectral methods, for example, three-dimensional (3D) fluorescence, Fourier-transformed infrared (FT-IR), and Raman spectra. At 290 K, the binding constant was 2.44 × 105 L/mol, there was only one binding site between LMP and lipase. Static quenching was the quenching mechanism. The major forces were hydrogen bonding and van der Waals force. The binding of LMP to lipase impacted the microenvironment around tyrosine and tryptophan residues. The polarity around these residues was decreased and hydrophobicity was enhanced. This study not only revealed the binding mechanism of LMP on lipase but also provided scientific evidence for expanding the application of LMP in functional food industries.


Assuntos
Cogumelos Shiitake , Sítios de Ligação , Ligação de Hidrogênio , Lipase , Simulação de Acoplamento Molecular , Polissacarídeos , Ligação Proteica , Cogumelos Shiitake/química , Espectrometria de Fluorescência/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
19.
Opt Express ; 30(7): 10743-10757, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473034

RESUMO

In the paper, a quasi-symmetrical structure reconfigurable metasurfaces (QSRMS) is proposed to generate the full-polarization electromagnetic (EM) holographic imaging. A combination of metasurfaces and varactor that involves the position and the gap of loading varactor is explored to achieve low-loss characteristics. The loading of the capacitor allows the element of reconfigurable metasurfaces (RMS) to present quasi-central symmetry, thus reducing the coupling between co- and cross-polarization. Therefore, the phase shift of 310° and the amplitude loss of 1.3 dB in the two orthogonal directions are acquired at 5.2 GHz. And the 3dB-loss bandwidth reaches 15.67%. Based on the dual-polarization QSRMS, the amplitude and phase modulation (APM) of the EM field are implemented simultaneously using L-BFGS-B algorithm. The implementation process of holographic imaging shows that all polarization state of the Poincaré sphere can be realized by designing the phase distribution of the QSRMS. Furthermore, the multi-polarization multiplexing holographic imaging is also investigated in this research, indicating that the polarization carrying capacity (PCC) can be enhanced by increasing the aperture of the metasurfaces. The results of simulation and experiment reveal that there will be a broad application prospect in next-generation large-scale, multi-channel EM intellisense systems.

20.
Phys Rev Lett ; 129(10): 108301, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36112459

RESUMO

In the presence of long-range dispersal, epidemics spread in spatially disconnected regions known as clusters. Here, we characterize exactly their statistical properties in a solvable model, in both the supercritical (outbreak) and critical regimes. We identify two diverging length scales, corresponding to the bulk and the outskirt of the epidemic. We reveal a nontrivial critical exponent that governs the cluster number and the distribution of their sizes and of the distances between them. We also discuss applications to depinning avalanches with long-range elasticity.


Assuntos
Epidemias , Surtos de Doenças
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