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1.
Nanotechnology ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941985

RESUMO

Memristors have recently received substantial attention because of its promising and unique application scenes emerging in neuromorphic computing which can achieve gains in computation speed by mimicking the topology of brains in electronic circuits. Traditional memristors made of bulk MoO3 and HfO2, etc. suffer from low switching ratio, short durability and poor stability. In this work, a floating-gate memristor is developed based on a mixed-dimensional heterostructure which is comprised of two-dimensional (2D) molybdenum disulfide (MoS2) and 0-dimensional (0D) Au nanoparticles (AuNPs) separated by an insulating hexagonal boron nitride (h-BN) layer, hereafter, MoS2/h-BN/AuNPs. We find that under the modulation of back-gate voltages, the MoS2/h-BN/AuNPs device operates reliably between a high resistance state (HRS) and a low resistance state (LRS) and that it shows multiple stable LRS states, demonstrating high potential of our memristor in application of multibit storage. The modulation effect can be attributed to the electron quantum tunneling between the AuNPs charge-trapping layer and MoS2 channel. Our memristor exhibits excellent durability and stability: the HRS and LRS remain more than 104 s without obvious degradation and the on/off ratio retains > 104 after more than 3000 switching cycles. We also demonstrate frequency-dependent memory properties upon electrical and optical pulse stimuli.

2.
Int J Biol Macromol ; 273(Pt 1): 132783, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825285

RESUMO

In this study, a brand-new, easy, and environmentally friendly approach for chemically functionalizing 2,2,6,6-tetramethylpiperidinyloxyl radical (TEMPO)-oxidized cellulose nanofiber (TOCNF) to produce modified cellulose nanofiber (octadecylamine-citric acid-CNF) was proposed. Effects of octadecylamine (ODA)/TOCNF mass ratio on the chemical structure, morphology, surface hydrophobicity and oleophobicity were studied. According to Fourier transform infrared spectroscopy (FTIR) analysis, ODA was successfully grafted onto the TOCNF by simple citric acid (CA) esterification and amidation reactions. Scanning electron microscopy (SEM) showed that a new rough structure was formed on the ODA-CA-CNF surface. The water contact angle (WCA) and the castor oil contact angle (OCA) of the ODA-CA-CNF reached 139.6° and 130.6°, respectively. The high-grafting-amount ODA-CA-CNF was sprayed onto paper, and the OCA reached 118.4°, which indicated good oil-resistance performance. The low-grafting-amount ODA-CNF was applied in a pH-responsive indicator film, exhibiting a colour change in response to the pH level, which can be applied in smart food packaging. The ODA-CA-CNF with excellent water/oil-resistance properties and fluorine-free properties can replace petrochemical materials and can be used in the fields of fluorine-free oil-proof paper.


Assuntos
Celulose , Óxidos N-Cíclicos , Interações Hidrofóbicas e Hidrofílicas , Nanofibras , Nanofibras/química , Celulose/química , Óxidos N-Cíclicos/química , Aminas/química , Ácido Cítrico/química , Água/química , Espectroscopia de Infravermelho com Transformada de Fourier , Flúor/química , Propriedades de Superfície
3.
Inorg Chem ; 63(21): 9899-9906, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38743634

RESUMO

A series of new trigonal pyramidal {SeO2(OH)} bridging lanthanide-containing antimono-seleno-tungstates [H2N(CH3)2]8Na8Cs4H9[Ln2SeW4O11(OH)(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33)]2·32H2O [Ln = Tb (1), Dy (2), Ho (3), Er (4)] have been prepared by the synthetic strategy of simultaneously using the antimonotungstate precursor and simple material in an acidic aqueous solution and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, IR spectrometry, and thermogravimetric analysis. Their molecular structures contain an unprecedented hexameric polyoxoanion [Ln2SeW4O11(OH)(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33)]229- constituted by two equivalent trimeric subunits Ln2W4O9(H2O)4(SbW9O33)(SeW9O33)(Se1/2Sb1/2W9O33) bridged via two µ2-{SeO2(OH)} linkers. Furthermore, the catalytic oxidation of various aromatic sulfides and sulfur mustard simulant 2-chloroethyl ethyl sulfide (CEES) by compound 3 as the heterogeneous catalyst has been investigated, exhibiting high conversion and selectivity as well as good stability and recyclability.

4.
Cell Metab ; 36(5): 984-999.e8, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38642552

RESUMO

The relevance of biopterin metabolism in resistance to immune checkpoint blockade (ICB) therapy remains unknown. We demonstrate that the deficiency of quinoid dihydropteridine reductase (QDPR), a critical enzyme regulating biopterin metabolism, causes metabolite dihydrobiopterin (BH2) accumulation and decreases the ratio of tetrahydrobiopterin (BH4) to BH2 in pancreatic ductal adenocarcinomas (PDACs). The reduced BH4/BH2 ratio leads to an increase in reactive oxygen species (ROS) generation and a decrease in the distribution of H3K27me3 at CXCL1 promoter. Consequently, myeloid-derived suppressor cells are recruited to tumor microenvironment via CXCR2 causing resistance to ICB therapy. We discovered that BH4 supplementation is capable to restore the BH4/BH2 ratio, enhance anti-tumor immunity, and overcome ICB resistance in QDPR-deficient PDACs. Tumors with lower QDPR expression show decreased responsiveness to ICB therapy. These findings offer a novel strategy for selecting patient and combining therapies to improve the effectiveness of ICB therapy in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/metabolismo , Humanos , Animais , Camundongos , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Microambiente Tumoral , Linhagem Celular Tumoral , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos Endogâmicos C57BL , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Feminino , Masculino , Espécies Reativas de Oxigênio/metabolismo
5.
Plants (Basel) ; 13(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38475543

RESUMO

The diversity of anthocyanins is largely due to the action of glycosyltransferases, which add sugar moieties to anthocyanidins. Although a number of glycosyltransferases have been identified to glycosylate anthocyanidin in plants, the enzyme that catalyzes malvidin galactosylation remains unclear. In this study, we identified three rice varieties with different leaf color patterns, different anthocyanin accumulation patterns, and different expression patterns of anthocyanin biosynthesis genes (ABGs) to explore uridine diphosphate (UDP)-glycosyltransferases (UGTs) responsible for biosynthesis of galactosylated malvidin. Based on correlation analysis of transcriptome data, nine candidate UGT genes coexpressed with 12 ABGs were identified (r values range from 0.27 to 1.00). Further analysis showed that the expression levels of one candidate gene, OsUGT88C3, were highly correlated with the contents of malvidin 3-O-galactoside, and recombinant OsUGT88C3 catalyzed production of malvidin 3-O-galactoside using UDP-galactose and malvidin as substrates. OsUGT88C3 was closely related to UGTs with flavone and flavonol glycosylation activities in phylogeny. Its plant secondary product glycosyltransferase (PSPG) motif ended with glutamine. Haplotype analysis suggested that the malvidin galactosylation function of OsUGT88C3 was conserved among most of the rice germplasms. OsUGT88C3 was highly expressed in the leaf, pistil, and embryo, and its protein was located in the endoplasmic reticulum and nucleus. Our findings indicate that OsUGT88C3 is responsible for the biosynthesis of malvidin 3-O-galactoside in rice and provide insight into the biosynthesis of anthocyanin in plants.

6.
Foods ; 12(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37835256

RESUMO

Facing extreme pressure from an increasing population and climate degeneration, it is important to explore a green, safe and environmentally sustainable food source, especially for protein-enriched diets. Plant proteins have gained much attention in recent years, ascribing to their high nutritional value and environmental friendliness. In this review, we summarized recent advances in walnut protein with respect to its geographical distribution, structural and physiochemical properties and functional attributes. As a worldwide cultivated and largely consumptive crop, allergies and some physicochemical limitations have also led to a few concerns about walnut protein. Through comprehensive analysis and discussion, some strategies may be useful for future research, extraction and processing of walnut protein.

7.
Nano Lett ; 23(15): 6799-6806, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37486984

RESUMO

Near the magic angle, strong correlations drive many intriguing phases in twisted bilayer graphene (tBG) including unconventional superconductivity and chern insulation. Whether correlations can tune symmetry breaking phases in tBG at intermediate (≳ 2°) twist angles remains an open fundamental question. Here, using ARPES, we study the effects of many-body interactions and displacement field on the band structure of tBG devices at an intermediate (3°) twist angle. We observe a layer- and doping-dependent renormalization of bands at the K points that is qualitatively consistent with moiré models of the Hartree-Fock interaction. We provide evidence of correlation-enhanced inversion symmetry-breaking, manifested by gaps at the Dirac points that are tunable with doping. These results suggest that electronic interactions play a significant role in the physics of tBG even at intermediate twist angles and present a new pathway toward engineering band structure and symmetry-breaking phases in moiré heterostructures.

8.
Materials (Basel) ; 16(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37512372

RESUMO

Laser additively manufactured (LAM) Ti-6Al-4V alloy has huge application potential in aerospace structural parts such as turbine blades. However, there are few studies on the fatigue properties of such LAM parts under vibration loading, particularly with regard to anisotropy. In this paper, vibration fatigue properties of LAM Ti-6Al-4V by laser melted deposition were investigated along the transversely deposited (TD) and parallelly deposited (PD) directions. Through the first-order bending vibration experiments, the LAM Ti-6Al-4V alloy exhibits obvious anisotropic fatigue properties and significant dispersion in fracture position. The fracture morphology analysis reveals that the vibration fatigue failure was mainly dominated by process-induced defects and microstructure. The fatigue strength at 106 cycles of the samples with defect-free failure features (DFF) at initiation sites is 470.9 MPa in PD and 434.2 Mpa in TD, while that of the samples with defect-related failure features (DRF) at initiation sites is 364.2 Mpa in PD and 381.0 Mpa in TD. For the DFF group, the fatigue behavior is controlled by the prior ß columnar grains with preferential orientation, which leads to enhanced fatigue crack propagation resistance for the PD samples. For the DRF group, which has lower fatigue lives, the fatigue anisotropy strongly depends on the projection area of the lack-of-fusion defects relative to the loading direction, resulting in better fatigue performance for the TD samples.

9.
Cancer Res ; 83(18): 3059-3076, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37326469

RESUMO

The therapeutic options for treating pancreatic ductal adenocarcinoma (PDAC) are limited, and resistance to gemcitabine, a cornerstone of PDAC chemotherapy regimens, remains a major challenge. N6-methyladenosine (m6A) is a prevalent modification in mRNA that has been linked to diverse biological processes in human diseases. Herein, by characterizing the global m6A profile in a panel of gemcitabine-sensitive and gemcitabine-insensitive PDAC cells, we identified a key role for elevated m6A modification of the master G0-G1 regulator FZR1 in regulating gemcitabine sensitivity. Targeting FZR1 m6A modification augmented the response to gemcitabine treatment in gemcitabine-resistant PDAC cells both in vitro and in vivo. Mechanistically, GEMIN5 was identified as a novel m6A mediator that specifically bound to m6A-modified FZR1 and recruited the eIF3 translation initiation complex to accelerate FZR1 translation. FZR1 upregulation maintained the G0-G1 quiescent state and suppressed gemcitabine sensitivity in PDAC cells. Clinical analysis further demonstrated that both high levels of FZR1 m6A modification and FZR1 protein corresponded to poor response to gemcitabine. These findings reveal the critical function of m6A modification in regulating gemcitabine sensitivity in PDAC and identify the FZR1-GEMIN5 axis as a potential target to enhance gemcitabine response. SIGNIFICANCE: Increased FZR1 translation induced by m6A modification engenders a gemcitabine-resistant phenotype by inducing a quiescent state and confers a targetable vulnerability to improve treatment response in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Proteínas Cdh1 , Linhagem Celular Tumoral , Gencitabina/farmacologia , Gencitabina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , RNA Mensageiro/genética , Neoplasias Pancreáticas
10.
Small ; 19(34): e2301574, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093221

RESUMO

The development of electric vehicles has received worldwide attention in the background of reducing carbon emissions, wherein lithium-ion batteries (LIBs) become the primary energy supply systems. However, commercial graphite-based anodes in LIBs currently confront significant difficulty in enduring ultrahigh power input due to the slow Li+ transport rate and the low intercalation potential. This will, in turn, cause dramatic capacity decay and lithium plating. The 2D layered materials (2DLMs) recently emerge as new fast-charging anodes and hold huge promise for resolving the problems owing to the synergistic effect of a lower Li+ diffusion barrier, a proper Li+ intercalation potential, and a higher theoretical specific capacity with using them. In this review, the background and fundamentals of fast-charging for LIBs are first introduced. Then the research progress recently made for 2DLMs used for fast-charging anodes are elaborated and discussed. Some emerging research directions in this field with a short outlook on future studies are further discussed.

11.
Angew Chem Int Ed Engl ; 62(19): e202218546, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36853171

RESUMO

The liquid-air interface offers a platform for the in-plane growth of free-standing materials. However, it is rarely used for inorganic perovskites and ultrathin non-layered perovskites. Herein the liquid-air interfacial synthesis of inorganic perovskite nanosheets (Cs3 Bi2 I9 , Cs3 Sb2 I9 ) is achieved simply by drop-casting the precursor solution with only the addition of iodine. The products are inaccessible without iodine addition. The thickness and lateral size of these nanosheets can be adjusted through the iodine concentration. The high volatility of the iodine spontaneously drives precursors that normally stay in the liquid to the liquid-air interface. The iodine also repairs in situ iodine vacancies during perovskite growth, giving enhanced optical and optoelectronic properties. The liquid-air interfacial growth of ultrathin perovskites provides multi-degree-of-freedom for constructing perovskite-based heterostructures and devices at atomic scale.

12.
Br J Nutr ; 130(4): 588-603, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36408747

RESUMO

Hormone-sensitive lipase (HSL) is one of the rate-determining enzymes in the hydrolysis of TAG, playing a crucial role in lipid metabolism. However, the role of HSL-mediated lipolysis in systemic nutrient homoeostasis has not been intensively understood. Therefore, we used CRISPR/Cas9 technique and Hsl inhibitor (HSL-IN-1) to establish hsla-deficient (hsla-/-) and Hsl-inhibited zebrafish models, respectively. As a result, the hsla-/- zebrafish showed retarded growth and reduced oxygen consumption rate, accompanied with higher mRNA expression of the genes related to inflammation and apoptosis in liver and muscle. Furthermore, hsla-/- and HSL-IN-1-treated zebrafish both exhibited severe fat deposition, whereas their expressions of the genes related to lipolysis and fatty acid oxidation were markedly reduced. The TLC results also showed that the dysfunction of Hsl changed the whole-body lipid profile, including increasing the content of TG and decreasing the proportion of phospholipids. In addition, the systemic metabolic pattern was remodelled in hsla-/- and HSL-IN-1-treated zebrafish. The dysfunction of Hsl lowered the glycogen content in liver and muscle and enhanced the utilisation of glucose plus the expressions of glucose transporter and glycolysis genes. Besides, the whole-body protein content had significantly decreased in the hsla-/- and HSL-IN-1-treated zebrafish, accompanied with the lower activation of the mTOR pathway and enhanced protein and amino acid catabolism. Taken together, Hsl plays an essential role in energy homoeostasis, and its dysfunction would cause the disturbance of lipid catabolism but enhanced breakdown of glycogen and protein for energy compensation.


Assuntos
Esterol Esterase , Peixe-Zebra , Animais , Esterol Esterase/genética , Esterol Esterase/metabolismo , Peixe-Zebra/metabolismo , Lipase/metabolismo , Lipólise/genética , Metabolismo dos Lipídeos/genética , Lipídeos , Nutrientes
13.
Int J Mol Sci ; 23(22)2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36430914

RESUMO

It is a macro-micro model study for defect initiation, growth and crack propagation of metallic truss structure under high engine temperature and pressure conditions during the reentry atmosphere. Till now, the multi-scale simulation methods for these processes are still unclear. We explore the deformation and failure processes from macroscale to nanoscale using the Gas-Kinetic Unified Algorithm (GKUA) and all-atomic, molecular dynamic (MD) simulation method. The behaviors of the dislocations, defect evolution and crack propagation until failure for Aluminum-Magnesium (Al-Mg) alloy are considered with the different temperature background and strain fields. The results of distributions of temperature and strain field in the aerodynamic environment obtained by molecular dynamics simulations are in good agreement with those obtained from the macroscopic Boltzmann method. Compared to the tensile loading, the alloy structure is more sensitive to compression loading. The polycrystalline Al-Mg alloy has higher yield strength with a larger grain size. It is due to the translation of plastic deformation mode from grain boundary (GB) sliding to dislocation slip and the accumulation of dislocation line. Our findings have paved a new way to analyze and predict the metallic structural failure by micro-scale analysis under the aerodynamic thermal extreme environment of the reentry spacecraft on service expiration.


Assuntos
Ambientes Extremos , Plásticos , Ligas , Cinética , Simulação de Dinâmica Molecular , Antiácidos , Grão Comestível
14.
J Agric Food Chem ; 70(40): 12830-12840, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36183268

RESUMO

Phytohormone abscisic acid (ABA) influences the shelf life of fruit, vegetables, and tubers after harvest. However, little is known about the core signaling module involved in ABA's control of the postharvest physiological process. Exogenous ABA alleviated postharvest physiological deterioration (PPD) symptoms of sliced cassava tuberous roots, increased endogenous ABA levels, and reduced endogenous H2O2 content. The specific ABA signaling module during the PPD process was identified as MePYL6-MePP2C16-MeSnRK2.1-MebZIP5/34. MebZIP5/MebZIP34 directly binds to and activates the promoters of MeGRX6/MeMDAR1 through ABRE elements. Exogenous ABA significantly induced the expression of genes involved in this module, glutaredoxin content, and monodehydroascorbate reductase activity. We presented a hypothesis suggesting that MePYL6-MePP2C16-MeSnRK2.1-MebZIP5/34-MeGRX6/MeMDAR1 is involved in ABA-induced antioxidative capacity, thus alleviating PPD symptoms in cassava tuberous roots. The identification of the specific signaling module involved in ABA's control of PPD provides a basis and potential targets for extending the shelf life of cassava tuberous roots.


Assuntos
Ácido Abscísico , Manihot , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Glutarredoxinas/genética , Peróxido de Hidrogênio/metabolismo , Manihot/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/metabolismo
15.
Front Pharmacol ; 13: 962596, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110551

RESUMO

Immune checkpoint inhibitors (ICIs) are the most notable breakthrough in tumor treatment. ICIs has been widely used in tumor patients, but its wide range of immune-related adverse events (irAEs) should not be ignored. irAEs can be involved in any organ system, including immune-related cardiotoxicity. Although the cardiotoxicity induced by immune checkpoint inhibitors is rare, it is extremely lethal and has attracted increasing attention. PD-1 and PD-L1 are expressed in human cardiomyocytes, so the application of PD-1/PDL-1 inhibitors can cause many adverse reactions to the cardiovascular system. This review summarizes the latest epidemiological evidence on the cardiovascular toxicity of programmed cell death protein-1(PD-1)/programmed cell death ligand-1(PD-L1) inhibitors and the clinical manifestations, as well as the potential pathological mechanisms. These updates may provide a novel perspective for monitoring early toxicity and establishing appropriate treatment for patients with ICI-related cardiotoxicity.

16.
Nature ; 609(7925): 52-57, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045239

RESUMO

Moiré patterns of transition metal dichalcogenide heterobilayers have proved to be an ideal platform on which to host unusual correlated electronic phases, emerging magnetism and correlated exciton physics. Whereas the existence of new moiré excitonic states is established1-4 through optical measurements, the microscopic nature of these states is still poorly understood, often relying on empirically fit models. Here, combining large-scale first-principles GW (where G and W denote the one-particle Green's function and the screened Coulomb interaction, respectively) plus Bethe-Salpeter calculations and micro-reflection spectroscopy, we identify the nature of the exciton resonances in WSe2/WS2 moiré superlattices, discovering a rich set of moiré excitons that cannot be captured by prevailing continuum models. Our calculations show moiré excitons with distinct characters, including modulated Wannier excitons and previously unidentified intralayer charge-transfer excitons. Signatures of these distinct excitonic characters are confirmed experimentally by the unique carrier-density and magnetic-field dependences of different moiré exciton resonances. Our study highlights the highly non-trivial exciton states that can emerge in transition metal dichalcogenide moiré superlattices, and suggests new ways of tuning many-body physics in moiré systems by engineering excited-states with specific spatial characters.

17.
Small ; 18(28): e2202557, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35718880

RESUMO

Lithium sulfur (Li-S) batteries are expected to become the next-generation rechargeable energy storage devices owing to their high theoretical energy density, environmental benignity, and economic benefits. However, the undesirable lithium polysulfides (LiPSs) shuttling and sluggish redox kinetics of sulfur electrochemistry severely degenerate the wide-ranging electrochemical performances, hindering the commercialization process of Li-S batteries. Herein, a Fe and V coordinated bimetallic oxide FeVO4 (denote FVO) nanocatalyst with three-dimensional (3D) ordered structure is thoughtfully tailored and cooperated with the commercialized carbon nanotubes (CNT) to modify polypropylene (PP) separator for achieving high efficiencies of restraining the LiPSs shuttling and boosting the redox conversion of sulfur species. The Fe and V coordinated bimetallic oxide demonstrates enhanced anchoring and catalyzing activities toward sulfur species than single metal oxides of Fe and V with homometallic valence states due to the reconfiguration of the 3d-band. Impressively, the Li-S pouch cell with the FVO/CNT@PP separator achieves an energy density up to 341 Wh kg-1 . The bimetallic oxide nanocatalyst used in this work enlightens a new designing route toward the separator modification for the development of high energy density Li-S batteries.

18.
Food Chem ; 382: 132367, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35152027

RESUMO

The wide use of high-fat diet (HFD) causes negative effects on flesh quality in farmed fish. l-carnitine, a lipid-lowering additive, enhances mitochondrial fatty acid ß-oxidation. However its roles in alleviating the effects of HFD on flesh quality in fish are unknown. We fed Nile tilapia with medium-fat diet (MFD, 6% dietary lipid), high-fat diet (HFD, 12% dietary lipid) and HFCD supplemented with l-carnitine (HFCD + 400 mg/kg l-carnitine) for 10 weeks. The HFD-fed fish had higher fat deposition, pH value, myofiber density and flesh hardness than those fed on MFD. However, feeding the fish with the HFCD improved lipid catabolism, which increased significantly lactic acid content and myofiber diameter in muscle, thus reduced pH and hardness values. HFCD also reduced endoplasmic reticulum stress and myofiber apoptosis caused by HFD in the fish. Our study suggests that dietary l-carnitine supplementation alleviates the negative effects of HFD on flesh quality of farmed fish.


Assuntos
Ciclídeos , Ração Animal/análise , Animais , Carnitina/metabolismo , Ciclídeos/metabolismo , Dieta , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Dureza , Concentração de Íons de Hidrogênio
19.
J Biomol Struct Dyn ; 40(1): 290-296, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32856528

RESUMO

Polyamine transporter (PAT) is a protein that can deliver "drug-polyamine" conjugates to tumor cells. 4-Chloro-naphthalimide- homospermidine (4-ClNAHSPD) displayed good antitumor activity and excellent cell selectivity via PAT pathway. In this paper, 4-ClNAHSPD and spermidine (SPD) were docked against PAT. The results showed that 4-ClNAHSPD could bind to PAT through hydrogen bond, Van der Waals, salt bridge or attractive charge and hydrophobic interaction. The interaction of SPD and PAT, however, was hydrogen bond and Van der Waals interaction. Moreover, their binding sites were also different. The primary binding sites of 4-ClNAHSPD with PAT are the residues of VAL59, HIS222, ASP61, ASP179 and GLU64, while SPD interacts with PAT in the sites of ASP37, ASP244, APS275 and SER36. The docked ligand-protein complexes were simulated for 5000ps. In simulations, various binding sites further resulted in the diverse root-mean-square deviation (RMSD) and root-mean-square deviation fluctuation (RMSF) values. The RMSD and RMSF values of 4-ClNAHSPD-PAT indicated that 4-ClNAHSPD caused a weak conformational change of PAT in a different style from SPD. More importantly, the interaction force numbers of 4-ClNAHSPD-PAT were also changed after the simulation. These results supported that 4-ClNAHSPD harnesses PAT pathway for cellular entrance.Communicated by Ramaswamy H. Sarma.


Assuntos
Simulação de Dinâmica Molecular , Naftalimidas , Ligantes , Simulação de Acoplamento Molecular , Poliaminas
20.
Adv Sci (Weinh) ; 9(2): e2103460, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34841726

RESUMO

Studying two-dimensional (2D) van der Waals (vdW) moiré superlattices and their interlayer interactions have received surging attention after recent discoveries of many new phases of matter that are highly tunable. Different atomistic registry between layers forming the inner and outer nanotubes can also form one-dimensional (1D) vdW moiré superlattices. In this review, experimental observations and theoretical perspectives related to interlayer interactions in 1D vdW moiré superlattices are summarized. The discussion focuses on double-walled carbon nanotubes (DWNTs), a model 1D vdW moiré system, and the authors highlight the new optical features emerging from the non-trivial strong interlayer coupling effect and the unique physics in 1D DWNTs. Future directions and questions in probing the intriguing physical phenomena in 1D vdW moiré superlattices such as, correlated physics in different 1D moiré systems beyond DWNTs are proposed and discussed.

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