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1.
Adv Mater ; : e2314031, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509794

RESUMO

Electrocatalytic water splitting is crucial to generate clean hydrogen fuel, but implementation at an industrial scale remains limited due to dependence on expensive platinum (Pt)-based electrocatalysts. Here, an all-dry process to transform electrochemically inert bulk WS2 into a multidomain electrochemical catalyst that enables scalable and cost-effective implementation of the hydrogen evolution reaction (HER) in water electrolysis is reported. Direct dry transfer of WS2 flakes to a gold thin film deposited on a silicon substrate provides a general platform to produce the working electrodes for HER with tunable charge transfer resistance. By treating the mechanically exfoliated WS2 with sequential Ar-O2 plasma, mixed domains of WS2, WO3, and tungsten oxysulfide form on the surfaces of the flakes, which gives rise to a superior HER with much greater long-term stability and steady-state activity compared to Pt. Using density functional theory, ultraefficient atomic sites formed on the constituent nanodomains are identified, and the quantification of atomic-scale reactivities and resulting HER activities fully support the experimental observations.

3.
EMBO Mol Med ; 16(1): 40-63, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177528

RESUMO

Despite intensive clinical and scientific efforts, the mortality rate of sepsis remains high due to the lack of precise biomarkers for patient stratification and therapeutic guidance. Secreted human tryptophanyl-tRNA synthetase 1 (WARS1), an endogenous ligand for Toll-like receptor (TLR) 2 and TLR4 against infection, activates the genes that signify the hyperinflammatory sepsis phenotype. High plasma WARS1 levels stratified the early death of critically ill patients with sepsis, along with elevated levels of cytokines, chemokines, and lactate, as well as increased numbers of absolute neutrophils and monocytes, and higher Sequential Organ Failure Assessment (SOFA) scores. These symptoms were recapitulated in severely ill septic mice with hypercytokinemia. Further, injection of WARS1 into mildly septic mice worsened morbidity and mortality. We created an anti-human WARS1-neutralizing antibody that suppresses proinflammatory cytokine expression in marmosets with endotoxemia. Administration of this antibody into severe septic mice attenuated cytokine storm, organ failure, and early mortality. With antibiotics, the antibody almost completely prevented fatalities. These data imply that blood-circulating WARS1-guided anti-WARS1 therapy may provide a novel theranostic strategy for life-threatening systemic hyperinflammatory sepsis.


Assuntos
Sepse , Triptofano-tRNA Ligase , Humanos , Animais , Camundongos , Triptofano-tRNA Ligase/genética , Medicina de Precisão , Citocinas/metabolismo , Quimiocinas
4.
Artigo em Inglês | MEDLINE | ID: mdl-38285587

RESUMO

Work-related musculoskeletal disorders represent a major occupational disability issue, and 53.4% of these disorders occur in the back or shoulders. Various types of passive shoulder exoskeletons have been introduced to support the weight of the upper arm and work tools during overhead work, thereby preventing injuries and improving the work environment. The general passive shoulder exoskeleton is constructed with rigid links and joints to implement shoulder rotation, but there exists a challenge to align with the flexible joint movements of the human shoulder. Also, a force-generating part using mechanical springs require additional mechanical components to generate torque similar to the shoulder joint, resulting in increased overall volume and inertia to the upper arm. In this study, we propose a new type of passive shoulder exoskeleton that uses magnetic spring joint and link chain. The redundant degrees of freedom in the link chains enables to follow the shoulder joint movement in the horizontal direction, and the magnetic spring joint generates torque without additional parts in a compact form. Conventional exoskeletons experience a loss in the assisting torque when the center of shoulder rotation changed during arm elevation. Our exoskeleton minimizes the torque loss by customizing the installation height and initial angle of the magnetic spring joint. The performances of the proposed exoskeleton were verified by an electromyographic evaluation of shoulder-related muscles in overhead work and box lifting task.


Assuntos
Exoesqueleto Energizado , Ombro , Humanos , Ombro/fisiologia , Fenômenos Biomecânicos , Extremidade Superior , Fenômenos Magnéticos , Eletromiografia
5.
J Adv Res ; 57: 135-147, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37061215

RESUMO

INTRODUCTION: Apocynin (Apo), an NADPH oxidase (NOX) inhibitor, has been widely used to treat various inflammatory diseases. However, the therapeutic effects of Apo on benign prostatic hyperplasia (BPH), a multifactorial disease associated with chronic inflammation and hormone imbalance, remain unknown. OBJECTIVES: The link between androgen signaling, reactive oxygen species (ROS), and prostate cell proliferation may contribute to the pathogenesis of BPH; therefore, the aim of this study was to identify the specific signaling pathway involved and to demonstrate whether the anti-oxidant Apo plays a role in the prevention and treatment of BPH. METHODS: Ingenuity pathway analysis and si-RNA transfection were conducted to demonstrate the androgen receptor (AR) and NOX4 linkage in BPH. Pathological markers of BPH were measured by H&E staining, immunoblotting, ELISA, qRT-PCR, and immunofluorescence to examine the effect of Apo. Rats stimulated with testosterone and BPH-1 cells were used as BPH models. RESULTS: AR and NOX4 network-mediated oxidative stress was upregulated in the BPH model. Next, we examined the effects of Apo on oxidative stress and chronic prostatic inflammation in BPH mouse models. In a testosterone-induced BPH rat model, Apo alleviated pathological prostate enlargement and suppressed androgen/AR signaling. Apo suppressed the upregulation of proinflammatory markers and promoted the expression of anti-oxidant factors. Furthermore, Apo regulated the TGF-ß/Glut9/activin pathway and macrophage programming. In BPH-1 cells, Apo suppressed AR-mediated proliferation and upregulation of TGFB and NOX4 expression by alleviating oxidative stress. Apo activated anti-oxidant and anti-inflammatory systems and regulated macrophage polarization in BPH-1 cells. AR knockdown partially abolished the beneficial effects of Apo in prostate cells, indicating AR-dependent effects of Apo. CONCLUSION: In contrast with existing BPH therapies, Apo may provide a new application for prostatic disease treatment, especially for BPH, by targeting the AR/TGF-ß/NOX4 signaling pathway.


Assuntos
Acetofenonas , Androgênios , Hiperplasia Prostática , Camundongos , Masculino , Humanos , Animais , Ratos , Receptores Androgênicos , Antioxidantes , Hiperplasia , Próstata , Hiperplasia Prostática/tratamento farmacológico , Inflamação/tratamento farmacológico , Testosterona , Proliferação de Células , NADPH Oxidase 4
6.
ACS Omega ; 8(48): 46267-46275, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075836

RESUMO

o-Phenylenediamine (OPD) is commonly used as a reliable signaling agent for colorimetric assays via oxidative dimerization to 2,3-diaminophenazine (DAP) (λmax = 425 nm), which is catalyzed by conventional horseradish peroxidase (HRP) or its nanoparticle mimics. Recently, it has been reported that catalytic and electrochemical oxidation of OPD produces a mixture of polymerized OPD molecules (polyOPDs), which could potentially affect the colorimetric signal due to the difference in optical properties between DAP and polyOPDs. In our study, we present for the first time that the gold nanoparticle-catalyzed oxidation of OPD could exhibit nonmonotonic extinction transitions at 425 nm. Using various spectroscopic and microscopic techniques such as UV-vis spectroscopy, transmission electron microscopy, dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy, we verify that the production of polyOPDs is specifically responsible for the unexpected decrease in extinction at 425 nm. This discovery presents a potential challenge to the conventionally accepted role of OPD as a signaling agent. Furthermore, we find that the modification of reaction variables, including reactant concentrations, anion types, and temperature, determines how nonmonotonic the extinction transition could be. Lastly, we develop an OPD-based colorimetric DNA detection scheme using DNA-functionalized gold nanoparticles to demonstrate the potential problems in accurately quantifying the target. Our proposal of using NaNO3 instead of NaCl to provide the desired ionic strength could be a suitable solution to overcome the obstacles of detection.

7.
Mar Drugs ; 21(11)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37999400

RESUMO

Microalgae have gained attention as a promising source of chlorophylls and carotenoids in various industries. However, scaling up of conventional bubble columns presents challenges related to cell sedimentation and the presence of non-photosynthetic cells due to non-circulating zones and decreased light accessibility, respectively. Therefore, this study aimed to evaluate the newly developed continuously circulated bioreactor ROSEMAX at both laboratory and pilot scales, compared to a conventional bubble column. There was no significant difference in the biomass production and photosynthetic pigment content of Tetraselmis sp. cultivated at the laboratory scale (p > 0.05). However, at the pilot scale, the biomass cultured in ROSEMAX showed significantly high biomass (1.69 ± 0.11 g/L, dry weight, DW), chlorophyll-a (14.60 ± 0.76 mg/g, DW), and total carotene (5.64 ± 0.81 mg/g, DW) concentrations compared to the conventional bubble column (1.17 ± 0.11 g/L, DW, 10.67 ± 0.72 mg/g, DW, 3.21 ± 0.56 mg/g, DW, respectively) (p ≤ 0.05). Flow cytometric analyses confirmed that the proportion of Tetraselmis sp. live cells in the culture medium of ROSEMAX was 32.90% higher than that in the conventional bubble column, with a photosynthetic efficiency 1.14 times higher. These results support suggestions to use ROSEMAX as a bioreactor for industrial-scale applications.


Assuntos
Microalgas , Fotossíntese , Reatores Biológicos , Carotenoides/análise , Clorofila A , Meios de Cultura , Biomassa
8.
Biomedicines ; 11(10)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37893216

RESUMO

Osteoarthritis (OA) is the most common joint disease that causes local inflammation and pain, significantly reducing the quality of life and normal social activities of patients. Currently, there are no disease-modifying OA drugs (DMOADs) available, and treatment relies on pain relief agents or arthroplasty. To address this significant unmet medical need, we aimed to develop monoclonal antibodies that can block the osteoclast-associated receptor (OSCAR). Our recent study has revealed the importance of OSCAR in OA pathogenesis as a novel catabolic regulator that induces chondrocyte apoptosis and accelerates articular cartilage destruction. It was also shown that blocking OSCAR with a soluble OSCAR decoy receptor ameliorated OA in animal models. In this study, OSCAR-neutralizing monoclonal antibodies were isolated and optimized by phage display. These antibodies bind to and directly neutralize OSCAR, unlike the decoy receptor, which binds to the ubiquitously expressed collagen and may result in reduced efficacy or deleterious off-target effects. The DMOAD potential of the anti-OSCAR antibodies was assessed with in vitro cell-based assays and an in vivo OA model. The results demonstrated that the anti-OSCAR antibodies significantly reduced cartilage destruction and other OA signs, such as subchondral bone plate sclerosis and loss of hyaline cartilage. Hence, blocking OSCAR with a monoclonal antibody could be a promising treatment strategy for OA.

9.
Bioresour Technol ; 390: 129827, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37802367

RESUMO

Low productivity and high cost remain major bottlenecks for the large-scale production of Haematococcus sp. This study explored biomass production and carotenoid accumulation in Haematococcus sp. (KCTC 12348BP) using drying film culture. The broth-cultured strain (3.2 × 106 cells/mL, 0.83 ± 0.02 mg/mL for a 21 d culture) was cultured under various conditions (different inoculum volumes and mist feeding intervals) in waterless agar plates at 28 ± 0.5 °C, under fluorescent light (12 h light-dark cycle) for 1 month. The maximum biomass obtained was 17.60 ± 0.72 g/m2, while the maximum astaxanthin concentration was 8.23 ± 1.13 mg/g in the culture using 1 mL inoculum and 3 d feeding interval. Drought stress in drying film culture effectively induced the accumulation of carotenoids from ß-carotene, facilitating the production of canthaxanthin via the astaxanthin biosynthesis pathway. This cost-effective culture system can increase the biomass and carotenoid pigment production in Haematococcus sp.


Assuntos
Clorofíceas , Clorófitas , Clorófitas/metabolismo , Carotenoides/metabolismo , Clorofíceas/metabolismo , Xantofilas/metabolismo , Biomassa
10.
ACS Omega ; 8(28): 25506-25514, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483246

RESUMO

AgCl nanomaterials recently attracted scientific interest as useful structural building blocks for producing metallic nanomaterials owing to their facile synthesis, controllable morphology, and ease of removal under ambient conditions. However, their complex chemical reactivity has primarily been studied in association with water solubility or reducibility. This study investigates the pivotal role of precursor ligands in the photochemical synthesis of metallic cubic mesh nanostructures on the AgCl templates. The side reactions between AgCl and Au precursors with different ligands are thoroughly discussed along with their influence on the byproduct formation and the structural stability of the resulting metallic nanostructures. Importantly, we introduce for the first time the partial destruction of AgCl and the formation of undesirable byproducts caused by the presence of highly oxidizing and Cl-containing AuCl4-. In addition, a synthetic route for producing highly pure and stable metallic nanostructures using a halogen-free Au precursor or Pt-priming is proposed. Further, the photothermal properties of these replicated metallic nanostructures are presented as a new evaluation tool for analyzing their overall structural stability. Discovering the role of precursor ligands in the reaction system will prove useful as a guide for the synthesis of functional noble metal nanomaterials using silver halide templates.

11.
Fish Shellfish Immunol ; 138: 108807, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37169112

RESUMO

The COVID-19 pandemic has significantly impacted human health for three years. To mitigate the spread of SARS-CoV-2, the development of neutralizing antibodies has been accelerated, including the exploration of alternative antibody formats such as single-domain antibodies. In this study, we identified variable new antigen receptors (VNARs) specific for the receptor binding domain (RBD) of SARS-CoV-2 by immunizing a banded houndshark (Triakis scyllium) with recombinant wild-type RBD. Notably, the CoV2NAR-1 clone showed high binding affinities in the nanomolar range to various RBDs and demonstrated neutralizing activity against SARS-CoV-2 pseudoviruses. These results highlight the potential of the banded houndshark as an animal model for the development of VNAR-based therapeutics or diagnostics against future pandemics.


Assuntos
COVID-19 , Anticorpos de Domínio Único , Humanos , Animais , SARS-CoV-2/metabolismo , Anticorpos Antivirais , Pandemias , Anticorpos Neutralizantes
12.
Bioconjug Chem ; 34(6): 1096-1104, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37170748

RESUMO

Recently, DNA-assembly nanoparticles based on DNA-metal ion interactions are emerging as new building blocks for drug delivery and metal nanostructure synthesis. However, the surface modification of DNA-assembly nanoparticles using functional biomolecules that can identify specific targets has rarely been explored. In this study, we developed a new immobilization chemical strategy to efficiently functionalize the barcode DNA-assembly nanoparticles (bcDNA NPs) with thiolated probe DNA (pDNA) for synthesizing pDNA-functionalized bcDNA NPs (pDNA-bcDNA NPs). We used them as nanoprobes to successfully demonstrate the sensitive and selective detection of multiple DNA targets. Importantly, Au ions played an essential role as anchoring sites via their conjugation with both thiolated pDNA and bcDNA NPs. In addition, we could reversibly and rapidly disassemble the pDNA-bcDNA NPs into the initial bcDNA strands with a recovery rate of 91%; this process significantly amplified the signal by releasing a million bcDNA strands, which enabled DNA quantification from a single pDNA-bcDNA NP. The Au3+ concentration, pH, and surface passivation conditions were carefully investigated to maximize the pDNA loading to 8500 strands/bcDNA NP. The limit of detection was determined to be 221 fM, which is the most sensitive among the absorbance-based methods without polymerase chain reaction, hybridization chain reactions, catalytic hairpin assembly, and other reactions involving enzymes and catalysts. The reversible disassembly of DNA strands and Au ion-mediated conjugation chemistry could be extended for the detection of other types of targets, such as proteins, metal ions, and small molecules, using other organic functionalities that are or can be thiolated, including polypeptides, aptamers, and antibodies.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Ouro/química , DNA/química , Íons
13.
Int J Biol Macromol ; 237: 124141, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36958447

RESUMO

Stability is critical for the proper functioning of all proteins. Optimization of protein thermostability is a key step in the development of industrial enzymes and biologics. Herein, we demonstrate that multidomain proteins can be stabilized significantly using domain-based engineering followed by the recombination of the optimized domains. Domain-level analysis of designed protein variants with similar structures but different thermal profiles showed that the independent enhancement of the thermostability of a constituent domain improves the overall stability of the whole multidomain protein. The crystal structure and AlphaFold-predicted model of the designed proteins via domain-recombination provided a molecular explanation for domain-based stepwise stabilization. Our study suggests that domain-based modular engineering can minimize the sequence space for calculations in computational design and experimental errors, thereby offering useful guidance for multidomain protein engineering.


Assuntos
Proteínas , Proteínas/química , Proteínas Mutantes/química , Estabilidade Enzimática
14.
Rev Sci Instrum ; 94(1): 013201, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725572

RESUMO

We developed a shutter driven by a solenoid to switch on/off the atomic beam of optical lattice clocks developed at KRISS [C. Y. Park et al., Metrologia 50, 119 (2013), S. Lee et al., New J. Phys. 18, 033030 (2016), H. Kim et al., Jpn. J. Appl. Phys. 56, 050302 (2017), and H. Kim et al., Metrologia 58, 055007 (2021)]. The shutter design was focused on long lifetime and compatibility with an ultra-high vacuum (UHV) environment. Thus, the solenoid was designed to be easily installed and removed from the air-side of a CF flange of the shutter. The flag in the vacuum-side moves only with the simple spring action of a sheet of a metal plate without any frictional movement of mechanical parts. All parts in the vacuum-side were made of metals (stainless steel and pure iron) to be baked over the temperature of 200 °C for UHV. The flag head of the shutter displaces up to 10 mm (5 mm) with a response time of 50 (30 ms) and 80 ms (10 ms) for the opening-action and the closing-action, respectively. The lifetime was tested up to 6 × 106 cycles with no performance degradation. We expect the actual lifetime to be much longer than this by virtue of its friction-free design.

15.
Cell Rep ; 42(1): 111905, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36640342

RESUMO

While cytoplasmic tryptophanyl-tRNA synthetase (WARS1) ligates tryptophan (Trp) to its cognate tRNAs for protein synthesis, it also plays a role as an innate immune activator in extracellular space. However, its secretion mechanism remains elusive. Here, we report that in response to stimuli, WARS1 can be secreted via two distinct pathways: via Trp-dependent secretion of naked protein and via Trp-independent plasma-membrane-derived vesicles (PMVs). In the direct pathway, Trp binding to WARS1 induces a "closed" conformation, generating a hydrophobic surface and basic pocket. The Trp-bound WARS1 then binds stable phosphatidylinositol (4,5)-biphosphate and inner plasma membrane leaflet, passing across the membrane. In the PMV-mediated secretion, WARS1 recruits calpain 2, which is activated by calcium. WARS1 released from PMVs induces inflammatory responses in vivo. These results provide insights into the secretion mechanisms of WARS1 and improve our understanding of how WARS1 is involved in the control of local and systemic inflammation upon infection.


Assuntos
Triptofano-tRNA Ligase , Humanos , Triptofano-tRNA Ligase/genética , Triptofano/metabolismo , Inflamação
16.
Mol Pharm ; 20(2): 1247-1255, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36563318

RESUMO

Endothelin receptor A (ETA), a class A G protein-coupled receptor (GPCR), is a promising tumor-associated antigen due to its close association with the progression and metastasis of many types of cancer, such as colorectal, breast, lung, ovarian, and prostate cancer. However, only small-molecule drugs have been developed as ETA antagonists with anticancer effects. In a previous study, we identified an antibody (AG8) with highly selective binding to human ETA through screening of a human naïve immune antibody library. Although both in vitro and in vivo experiments indicated that the identified AG8 had anticancer effects, there is a need for improvement in biochemical and physicochemical properties such as the ETA binding affinity, thermostability, and productivity. In this study, we engineered the framework regions of AG8 and isolated an anti-ETA antibody (MJF1) exhibiting significantly improved thermostability and ETA binding affinity. Subsequently, our previously isolated PFc29, an Fc variant with an enhanced pH-dependent human FcRn binding profile, was introduced to MJF1, and the resulting Fc-engineered anti-ETA antibody (MJF1-PFc29) inhibited the proliferation of tumor cells comparably to MJF1 and showed a 4.2-fold increased serum half-life in human FcRn transgenic mice. Moreover, MJF1-PFc29 elicited higher tumor growth inhibition in colorectal cancer xenograft mice compared to MJF1. Our results demonstrate that the engineered human anti-ETA antibody MJF1-PFc29 has great therapeutic potential and high antitumor potency against various types of cancers including colorectal cancer.


Assuntos
Neoplasias Colorretais , Engenharia de Proteínas , Masculino , Humanos , Camundongos , Animais , Receptores Fc/metabolismo , Camundongos Transgênicos , Receptor de Endotelina A , Neoplasias Colorretais/tratamento farmacológico
17.
Adv Mater ; 35(8): e2209500, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36462219

RESUMO

Hindered gas bubble release and limited electron conducting process represent the major bottlenecks for large-scale electrochemical water splitting. Both the desorption of bubbles and continuous electron transport are achievable on the surfaces of biomimetic catalytic materials by designing multiscale structural hierarchy. Inspired by the tubular structures of the deep-sea sponges, an exceptionally active and binder-free porous nickel tube arrays (PNTA) decorated with NiFe-Zn2+ -pore nanosheets (NiFe-PZn ) are fabricated. The PNTA facilitate removal of bubbles and electron transfer in the oxygen evolution reaction by reproducing trunks of the sponges, and simultaneously, the NiFe-PZn increase the number of catalytic active sites by simulating the sponge epidermis. With improved external mass transfer and interior electron transfer, the hierarchical NiFe-PZn @PNTA electrode exhibits superior oxygen evolution reaction performance with an overpotential of 172 mV at 10 mA cm-2 (with a Tafel slope of 50 mV dec-1 ). Furthermore, this electrocatalytic system recorded excellent reaction stability over 360 h with a constant current density of 100 mA cm-2 at the potential of 1.52 V (versus RHE). This work provides a new strategy of designing hierarchical electrocatalysts for highly efficient water splitting.

18.
J Microbiol ; 60(11): 1086-1094, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36318359

RESUMO

Fibroblast growth factor 11 (FGF11) is one of intracrine FGFs (iFGFs), which function within cells. Unlike canonical FGFs, FGF11 remains intracellularly and plays biological roles in FGF receptor (FGFR)-independent manner. Here, we established an expression system of recombinant FGF11 proteins in E. coli and investigated whether the extracellular administration of FGF11 can activate cellular signaling. Human FGF11 has two isoforms, FGF11a and FGF11b, depending on the presence of nuclear localization sequences (NLSs) in the N-terminus. Because these two isoforms are unstable, we prepared an FGF11a-Mut by substituting three cysteine residues in the NLS with serine and FGF11b-ΔC with C-terminal truncation. The introduction of mutation in the NLS improved the solubility of FGF11 prepared from E. coli. Exogenous addition of FGF11b and FGF11b-ΔC to BALB3T3 increased cell proliferation, while FGF11a-Mut exerted no effect. FGF11b-ΔC showed higher cell proliferation activity and FGFR signaling than FGF11b. The cell-proliferating activities of FGF11b and FGF11b-ΔC were blocked by an FGFR1 inhibitor or a recombinant FGFR1, confirming the FGFR1-dependent extracellular activity of FGF11b. The analysis of circular dichroism suggested that the C-terminus of FGF11 has an α-helical structure, which may affect its interaction with FGFR1. These results suggest that the N-and C-terminus of recombinant FGF11 are involved in the activation of FGFR1. The above results provide novel insights into the function and mechanism of FGF11 that may aid the development of useful ligands for FGFR regulation.


Assuntos
Escherichia coli , Fatores de Crescimento de Fibroblastos , Humanos , Escherichia coli/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Proliferação de Células , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/metabolismo
19.
Small ; 18(48): e2205057, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36269881

RESUMO

Flat metasurfaces with subwavelength meta-atoms can be designed to manipulate the electromagnetic parameters of incident light and enable unusual light-matter interactions. Although hydrogel-based metasurfaces have the potential to control optical properties dynamically in response to environmental conditions, the pattern resolution of these surfaces has been limited to microscale features or larger, limiting capabilities at the nanoscale, and precluding effective use in metamaterials. This paper reports a general approach to developing tunable plasmonic metasurfaces with hydrogel meta-atoms at the subwavelength scale. Periodic arrays of hydrogel nanodots with continuously tunable diameters are fabricated on silver substrates, resulting in humidity-responsive surface plasmon polaritons (SPPs) at the nanostructure-metal interfaces. The peaks of the SPPs are controlled reversibly by absorbing or releasing water within the hydrogel matrix, the matrix-generated plasmonic color rendering in the visible spectrum. This work demonstrates that metasurfaces designed with these spatially patterned nanodots of varying sizes benefit applications in anti-counterfeiting and generate multicolored displays with single-nanodot resolution. Furthermore, this work shows system versatility exhibited by broadband beam-steering on a phase modulator consisting of hydrogel supercell units in which the size variations of constituent hydrogel nanostructures engineer the wavefront of reflected light from the metasurface.


Assuntos
Hidrogéis , Nanoestruturas , Prata , Umidade , Água
20.
Nutrients ; 14(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36145090

RESUMO

Spirulina maxima is a marine microalga that has been promoted worldwide as a super food. This study was conducted to evaluate its ability to improve memory in the older adults using Spirulina maxima 70% ethanol extract (SM70EE). This randomized, double-blind, placebo-controlled clinical trial comprised 80 volunteers recruited from Jeonbuk National University Hospital in Jeonju, Republic of Korea, who were randomly assigned to two groups. The participants received either 1 g/day of SM70EE or a placebo without otherwise changing their diet or physical activity. The participants were examined at baseline and after a 12-week interval to determine whether there were changes in their results for visual learning, visual working memory, and verbal learning tests from the Korean version of the Montreal Cognitive Assessment, brain-derived neurotrophic factor and beta-amyloid levels, and total antioxidant capacity. Compared to the placebo group, the treatment group showed a significant improvement in visual learning and visual working memory test results and enhanced vocabulary. SM70EE use was shown to improve memory, with no adverse effects. Its efficacy in alleviating Alzheimer's disease symptoms was verified for the first time through this clinical trial. SM70EE could play a role in the management of patients with dementia. This trial is registered with registration number of clinical research information service (CRIS: KCT0006161).


Assuntos
Disfunção Cognitiva , Spirulina , Idoso , Antioxidantes/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo , Disfunção Cognitiva/tratamento farmacológico , Método Duplo-Cego , Etanol , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
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