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1.
Proc Natl Acad Sci U S A ; 121(7): e2318970121, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38315838

RESUMEN

Solar-driven photocatalytic CO2 reduction is an energy-efficient and sustainable strategy to mitigate CO2 levels in the atmosphere. However, efficient and selective conversion of CO2 into multi-carbon products, like C2H4, remains a great challenge due to slow multi-electron-proton transfer and sluggish C-C coupling. Herein, a two-dimensional thin-layered hybrid perovskite is fabricated through filling of oxygen into iodine vacancy in pristine DMASnI3 (DMA = dimethylammonium). The rational-designed DMASnI3(O) induces shrinkage of active sites distance and facilitates dimerization of C-C coupling of intermediates. Upon simulated solar irradiation, the DMASnI3(O) photocatalyst achieves a high selectivity of 74.5%, corresponding to an impressive electron selectivity of 94.6%, for CO2 to C2H4 conversion and an effective C2H4 yield of 11.2 µmol g-1 h-1. In addition, the DMASnI3(O) inherits excellent water stability and implements long-term photocatalytic CO2 reduction to C2H4 in a water medium. This work establishes a unique paradigm to convert CO2 to C2+ hydrocarbons in a perovskite-based photocatalytic system.

2.
Proc Natl Acad Sci U S A ; 121(38): e2412031121, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39254999

RESUMEN

Higher-order topological phases in non-Hermitian photonics revolutionize the understanding of wave propagation and modulation, which lead to hierarchical states in open systems. However, intrinsic insulating properties endorsed by the lattice symmetry of photonic crystals fundamentally confine the robust transport only at explicit system boundaries, letting alone the flexible reconfiguration in hierarchical states at arbitrary positions. Here, we report a dynamic topological platform for creating the reconfigurable hierarchical bound states in heat transport systems and observe the robust and nonlocalized higher-order states in both the real- and imaginary-valued bands. Our experiments showcase that the hierarchical features of zero-dimension corner and nontrivial edge modes occur at tailored positions within the system bulk states instead of the explicit system boundaries. Our findings uncover the mechanism of non-localized hierarchical non-trivial topological states and offer distinct paradigms for diffusive transport field management.

3.
Proc Natl Acad Sci U S A ; 119(15): e2110018119, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35377805

RESUMEN

SignificanceThermal diffusion is dissipative and strongly related to non-Hermitian physics. At the same time, non-Hermitian Weyl systems have spurred tremendous interest across photonics and acoustics. This correlation has been long ignored and hence shed little light upon the question of whether the Weyl exceptional ring (WER) in thermal diffusion could exist. Intuitively, thermal diffusion provides no real parameter dimensions, thus prohibiting a topological nature and WER. This work breaks this perception by imitating synthetic dimensions via two spatiotemporal advection pairs. The WER is achieved in thermal diffusive systems. Both surface-like and bulk states are demonstrated by coupling two WERs with opposite topological charges. These findings extend topological notions to diffusions and motivate investigation of non-Hermitian diffusive and dissipative control.

4.
J Cell Mol Med ; 28(16): e70022, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39205384

RESUMEN

Under the long-term pressure overload stimulation, the heart experiences embryonic gene activation, leading to myocardial hypertrophy and ventricular remodelling, which can ultimately result in the development of heart failure. Identifying effective therapeutic targets is crucial for the prevention and treatment of myocardial hypertrophy. Histone lysine lactylation (HKla) is a novel post-translational modification that connects cellular metabolism with epigenetic regulation. However, the specific role of HKla in pathological cardiac hypertrophy remains unclear. Our study aims to investigate whether HKla modification plays a pathogenic role in the development of cardiac hypertrophy. The results demonstrate significant expression of HKla in cardiomyocytes derived from an animal model of cardiac hypertrophy induced by transverse aortic constriction surgery, and in neonatal mouse cardiomyocytes stimulated by Ang II. Furthermore, research indicates that HKla is influenced by glucose metabolism and lactate generation, exhibiting significant phenotypic variability in response to various environmental stimuli. In vitro experiments reveal that exogenous lactate and glucose can upregulate the expression of HKla and promote cardiac hypertrophy. Conversely, inhibition of lactate production using glycolysis inhibitor (2-DG), LDH inhibitor (oxamate) and LDHA inhibitor (GNE-140) reduces HKla levels and inhibits the development of cardiac hypertrophy. Collectively, these findings establish a pivotal role for H3K18la in pathological cardiac hypertrophy, offering a novel target for the treatment of this condition.


Asunto(s)
Cardiomegalia , Histonas , Ácido Láctico , Miocitos Cardíacos , Animales , Cardiomegalia/metabolismo , Cardiomegalia/patología , Histonas/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Miocitos Cardíacos/efectos de los fármacos , Ratones , Ácido Láctico/metabolismo , Procesamiento Proteico-Postraduccional , Modelos Animales de Enfermedad , Glucosa/metabolismo , Masculino , Lisina/metabolismo , Ratones Endogámicos C57BL , Glucólisis
5.
Plant J ; 116(1): 161-172, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37381795

RESUMEN

Ovules are female reproductive organs of angiosperms, consisting of sporophytic integuments surrounding female gametophytes, that is, embryo sacs. Synchronization between integument growth and embryo sac development requires intracellular communication. However, signaling routes through which cells of the two generations communicate are unclear. We report that symplastic signals through plasmodesmata (PDs) of integuments are critical for the development of female gametophytes. Genetic interferences of PD biogenesis either by functional loss of CHOLINE TRANSPORTER-LIKE1 (CTL1) or by integument-specific expression of a mutated CALLOSE SYNTHASE 3 (cals3m) compromised PD formation in integuments and reduced fertility. Close examination of pINO:cals3m or ctl1 ovules indicated that female gametophytic development was either arrested at various stages after the formation of functional megaspores. In both cases, defective ovules could not attract pollen tubes, leading to the failure of fertilization. Results presented here demonstrate a key role of the symplastic route in sporophytic control of female gametophytic development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fertilidad , Tubo Polínico/metabolismo
6.
Plant J ; 115(4): 895-909, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37133258

RESUMEN

Grain size is a key factor in determining rice (Oryza sativa) yield, and exploring new pathways to regulate grain size has immense potential to improve yield. In this study, we report that OsCBL5 encodes a calcineurin B subunit protein that significantly promotes grain size and weight. oscbl5 plants produced obviously smaller and lighter seeds. We further revealed that OsCBL5 promotes grain size by affecting cell expansion in the spikelet hull. Biochemical analyses demonstrated that CBL5 interacts with CIPK1 and PP23. Furthermore, double and triple mutations were induced using CRISPR/Cas9 (cr) to analyze the genetic relationship. It was found that the cr-cbl5/cipk1 phenotype was similar to that of cr-cipk1 and that the cr-cbl5/pp23, cr-cipk1/pp23, and cr-cbl5/cipk1/pp23 phenotype was similar to that of cr-pp23, indicating that OsCBL5, CIPK1, and PP23 act as a molecular module influencing seed size. In addition, the results show that both CBL5 and CIPK1 are involved in the gibberellic acid (GA) pathway and significantly affect the accumulation of endogenous active GA4 . PP23 participates in GA signal transduction. In brief, this study identified a new module that affects rice grain size, OsCBL5-CIPK1-PP23, which could potentially be targeted to improve rice yield.


Asunto(s)
Giberelinas , Oryza , Giberelinas/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Grano Comestible/genética , Regulación de la Expresión Génica de las Plantas
7.
Mol Plant Microbe Interact ; 37(1): 6-14, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37880815

RESUMEN

Numerous bacterial species employ diffusible signal factor (DSF)-based quorum sensing (QS) as a widely conserved cell-cell signaling communication system to collectively regulate various behaviors crucial for responding to environmental changes. cis-11-Methyl-dodecenoic acid, known as DSF, was first identified as a signaling molecule in Xanthomonas campestris pv. campestris. Subsequently, many structurally related molecules have been identified in different bacterial species. This review aims to provide an overview of current understanding regarding the biosynthesis and regulatory role of DSF signals in both pathogenic bacteria and a biocontrol bacterium. Recent studies have revealed that the DSF-based QS system regulates antimicrobial factor production in a cyclic dimeric GMP-independent manner in the biocontrol bacterium Lysobacter enzymogenes. Additionally, the DSF family signals have been found to be involved in suppressing plant innate immunity. The discovery of these diverse signaling mechanisms holds significant promise for developing novel strategies to combat stubborn plant pathogens. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Percepción de Quorum , Xanthomonas campestris , Transducción de Señal , GMP Cíclico , Proteínas Bacterianas/genética
8.
J Am Chem Soc ; 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38176108

RESUMEN

Seawater-flow- and -evaporation-induced electricity generation holds significant promise in advancing next-generation sustainable energy technologies. This method relies on the electrokinetic effect but faces substantial limitations when operating in a highly ion-concentrated environment, for example, natural seawater. We present herein a novel solution using calcium-based metal-organic frameworks (MOFs, C12H6Ca2O19·2H2O) for seawater-evaporation-induced electricity generation. Remarkably, Ca-MOFs show an open-circuit voltage of 0.4 V and a short-circuit current of 14 µA when immersed in seawater under natural conditions. Our experiments and simulations revealed that sodium (Na) ions selectively transport within sub-nanochannels of these synthetic superhydrophilic MOFs. This selective ion transport engenders a unipolar solution flow, which drives the electricity generation behavior in seawater. This work not only showcases an effective Ca-MOF for electricity generation through seawater flow/evaporation but also contributes significantly to our understanding of water-driven energy harvesting technologies and their potential applications beyond this specific context.

9.
Rep Prog Phys ; 87(9)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39121866

RESUMEN

Topological Anderson phases (TAPs) offer intriguing transitions from ordered to disordered systems in photonics and acoustics. However, achieving these transitions often involves cumbersome structural modifications to introduce disorders in parameters, leading to limitations in flexible tuning of topological properties and real-space control of TAPs. Here, we exploit disordered convective perturbations in a fixed heat transport system. Continuously tunable disorder-topology interactions are enabled in thermal dissipation through irregular convective lattices. In the presence of a weak convective disorder, the trivial diffusive system undergos TAP transition, characterized by the emergence of topologically protected corner modes. Further increasing the strength of convective perturbations, a second phase transition occurs converting from TAP to Anderson phase. Our work elucidates the pivotal role of disorders in topological heat transport and provides a novel recipe for manipulating thermal behaviors in diverse topological platforms.

10.
Br J Cancer ; 131(4): 655-667, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38951697

RESUMEN

BACKGROUND: DNMT3A is a crucial epigenetic regulation enzyme. However, due to its heterogeneous nature and frequent mutation in various cancers, the role of DNMT3A remains controversial. Here, we determine the role of DNMT3A in non-small cell lung cancer (NSCLC) to identify potential treatment strategies. METHODS: To investigate the role of loss-of-function mutations of DNMT3A in NSCLC, CRISPR/Cas9 was used to induce DNMT3A-inactivating mutations. Epigenetic inhibitor library was screened to find the synthetic lethal partner of DNMT3A. Both pharmacological inhibitors and gene manipulation were used to evaluate the synthetic lethal efficacy of DNMT3A/KDM1A in vitro and in vivo. Lastly, MS-PCR, ChIP-qPCR, dual luciferase reporter gene assay and clinical sample analysis were applied to elucidate the regulation mechanism of synthetic lethal interaction. RESULTS: We identified DNMT3A is a tumour suppressor gene in NSCLC and KDM1A as a synthetic lethal partner of DNMT3A deletion. Both chemical KDM1A inhibitors and gene manipulation can selectively reduce the viability of DNMT3A-KO cells through inducing cell apoptosis in vitro and in vivo. We clarified that the synthetic lethality is not only limited to the death mode, but also involved into tumour metastasis. Mechanistically, DNMT3A deficiency induces KDM1A upregulation through reducing the methylation status of the KDM1A promoter and analysis of clinical samples indicated that DNMT3A expression was negatively correlated with KDM1A level. CONCLUSION: Our results provide new insight into the role of DNMT3A in NSCLC and elucidate the mechanism of synthetic lethal interaction between KDM1A and DNMT3A, which might represent a promising approach for treating patients with DNMT3A-deficient tumours.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , ADN (Citosina-5-)-Metiltransferasas , ADN Metiltransferasa 3A , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Animales , Ratones , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , Histona Demetilasas/antagonistas & inhibidores , Línea Celular Tumoral , Apoptosis , Ensayos Antitumor por Modelo de Xenoinjerto , Regulación Neoplásica de la Expresión Génica , Femenino
11.
Apoptosis ; 29(1-2): 243-266, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37670104

RESUMEN

A particular GTPase-activating protein called RACGAP1 is involved in apoptosis, proliferation, invasion, metastasis, and drug resistance in a variety of malignancies. Nevertheless, the role of RACGAP1 in pan-cancer was less studied, and its value of the expression and prognostic of nasopharyngeal carcinoma (NPC) has not been explored. Hence, the goal of this study was to investigate the oncogenic and immunological roles of RACGAP1 in various cancers and its potential value in NPC. We comprehensively analyzed RACGAP1 expression, prognostic value, function, methylation levels, relationship with immune cells, immune infiltration, and immunotherapy response in pan-cancer utilizing multiple databases. The results discovered that RACGAP1 expression was elevated in most cancers and suggested poor prognosis, which could be related to the involvement of RACGAP1 in various cancer-related pathways such as the cell cycle and correlated with RACGAP1 methylation levels, immune cell infiltration and reaction to immunotherapy, and chemoresistance. RACGAP1 could inhibit anti-tumor immunity and immunotherapy responses by fostering immune cell infiltration and cytotoxic T lymphocyte dysfunction. Significantly, we validated that RACGAP1 mRNA and protein were highly expressed in NPC. The Gene Expression Omnibus database revealed that elevated RACGAP1 expression was associated with shorter PFS in patients with NPC, and RACGAP1 potentially influenced cell cycle progression, DNA replication, metabolism, and immune-related pathways, resulting in the recurrence and metastasis of NPC. This study indicated that RACGAP1 could be a potential biomarker in pan-cancer and NPC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Apoptosis/genética , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Neoplasias Nasofaríngeas/genética
12.
Anal Chem ; 96(22): 9185-9191, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38773762

RESUMEN

Successively emerged high-throughput multitarget molecular detection methods bring significant development tides in chemical, biological, and environmental fields. However, several persistent challenges of intricate sample preparation, expensive instruments, and tedious and skilled operations still need to be further addressed. Here, we propose an automatic light-addressable photoelectrochemical (ALA-PEC) sensing platform for sensitive and selective detection of multitarget molecules. With Au nanoparticle-decorated TiO2 nanotube photonic crystals (Au-TiO2 NTPCs) as a photoelectrode and 8 kinds of antibiotics as target molecules, the ALA-PEC sensing system implements automatic detection of multimolecules in a short time with high sensitivity and good selectivity. Random samples with different amounts of antibiotics have been well-distinguished in the ALA-PEC system, and both the chemical components and concentrations have been well-illustrated in a pattern recognition model. It is worth noting that 8 samples are not the limit of the ALA-PEC sensing platform, which can be easily expanded to more complex detection arrays based on practical needs. The emerging ALA-PEC sensing platform provides a new solution for rapid screening and detection of multitarget and high-throughput substances and potentially brings the automatic, portable, sensitive, high-throughput, and cost-effective detection technique to an entire new realm.

13.
Anal Chem ; 96(18): 6906-6913, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38656893

RESUMEN

Glycerol tributyrate as a low-density lipoprotein plays a crucial role in drug development and food safety. In this work, a novel high-stability fiber optic sensor for glyceryl tributyrate based on the poly(acrylic acid) (PAA) and chitosan (CS) composite hydrogel embedding method is first proposed. Compared with traditional functionalization, the lipase in a polymer network structure used in this article can not only avoid chemical reactions that cause damage to the enzyme structure but also avoid the instability of ionic bonds and physical adsorption. Therefore, the PAA/CS hydrogel method proposed in this article can effectively retain enzyme structure. First, the impact of different layers (one to five layers) of PAA/CS on pH sensing performance was explored, and it was determined that layers 1-3 could be used for subsequent sensing experiments. Within the linear detection range of 0.5-10 mM, the detection sensitivities of the one to three layers of the biosensor are divided into 0.65, 0.95, and 1.51 nm/mM, respectively, with the three layers having the best effect. When the number of coating layers is three, the detection limit of the sensor is 0.47 mM, meeting the millimole level detection standard for anticancer requirement. Furthermore, the stability and selectivity of the sensor (in the presence of hemoglobin, urea, cholesterol, acetylcholine, and glucose) were analyzed. The three-layer sensor is used for sample detection. At concentrations of 1-10 mM, the absolute value of the recovery percentage (%) is 82-99%, which can accurately detect samples. The sensor proposed in this paper has the advantages of low sample consumption, high sensitivity, simple structure, and label-free measurement. The enzyme-embedding method provides a new route for rapid and reliable glyceryl tributyrate detection, which has potential applications in food safety as well as the development of anticancer drugs.


Asunto(s)
Resinas Acrílicas , Quitosano , Fibras Ópticas , Resonancia por Plasmón de Superficie , Resinas Acrílicas/química , Quitosano/química , Hidrogeles/química , Límite de Detección , Lipasa/química , Lipasa/metabolismo , Técnicas Biosensibles/métodos
14.
Anal Chem ; 96(28): 11383-11389, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-38946419

RESUMEN

Apurinic/apyrimidinic endonuclease 1 (APE1), as a vital base excision repair enzyme, is essential for maintaining genomic integrity and stability, and its abnormal expression is closely associated with malignant tumors. Herein, we constructed an electrochemiluminescence (ECL) biosensor for detecting APE1 activity by combining nanoconfined ECL silver nanoclusters (Ag NCs) with X-shaped DNA recognizer-triggered cascade amplification. Specifically, the Ag NCs were prepared and confined in the glutaraldehyde-cross-linked chitosan hydrogel network using the one-pot method, resulting in a strong ECL response and exceptional stability in comparison with discrete Ag NCs. Furthermore, the self-assembled X-shaped DNA recognizers were designed for APE1 detection, which not only improved reaction kinetics due to the ordered arrangement of recognition sites but also achieved high sensitivity by utilizing the recognizer-triggered cascade amplification of strand displacement amplification (SDA) and DNAzyme catalysis. As expected, this biosensor achieved sensitive ECL detection of APE1 in the range of 1.0 × 10-3 U·µL-1 to 1.0 × 10-10 U·µL-1 with the detection limit of 2.21 × 10-11 U·µL-1, rendering it a desirable approach for biomarker detection.


Asunto(s)
Técnicas Biosensibles , ADN-(Sitio Apurínico o Apirimidínico) Liasa , Técnicas Electroquímicas , Mediciones Luminiscentes , Nanopartículas del Metal , Plata , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , ADN-(Sitio Apurínico o Apirimidínico) Liasa/análisis , Plata/química , Humanos , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodos , Técnicas Biosensibles/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , ADN/química , Límite de Detección , ADN Catalítico/química , ADN Catalítico/metabolismo
15.
Anal Chem ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39024185

RESUMEN

Precise and reliable monitoring of DNA adenine methyltransferase (Dam) activity is essential for disease diagnosis and biological analysis. However, existing techniques for detecting Dam activity often rely on specific DNA recognition probes that are susceptible to DNA degradation and exhibit limited target sensitivity and specificity. In this study, we designed and engineered a stable and dynamic DNA nanodevice called the double-loop interlocked DNA circuit (DOOR) that enables the sensitive and selective monitoring of Dam activity in complex biological environments. The DOOR incorporates two interlocked specialized sequences: a palindromic sequence for Dam identification and an initiator sequence for signal amplification. In the presence of Dam, the DOOR is cleaved by double-stranded DNA phosphodiesterase I endonuclease, generating massive double-stranded DNA (dsDNA) units. These units can self-assemble into a long dsDNA scaffold, thereby enhancing the subsequent reaction kinetics. The dsDNA scaffold further triggers a hyperbranched hybrid chain reaction to produce a fluorescent 3D DNA nanonet, enabling more precise monitoring of the Dam activity. The DOOR device exhibits excellent sensitivity, specificity, and stability, rendering it a powerful tool for studying DNA methylation in various biological processes and diseases.

16.
Anal Chem ; 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39392054

RESUMEN

Accurate and reliable detection of uracil-DNA glycosylase (UDG) activity is crucial for clinical diagnosis and prognosis assessment. However, current techniques for accurately monitoring UDG activity still face significant challenges due to the single input or output signal modes. Here, we develop a sequentially activated-dumbbell DNA nanodevice (SEAD) that enables precise and reliable evaluation of UDG activity through primer exchange reactions (PER)-based orthogonal signal output. The SEAD incorporates a double-hairpin structure with a stem containing two deoxyuridine (dU) sites for target recognition and two preblocked primer binding regions for target amplification and signal output. Upon UDG recognition of dU, the SEAD can be cleaved by apurinic/apyrimidinic endonuclease 1 (APE1), generating two different hairpins with exposed primer binding regions. These hairpins serve as templates to initiate the parallel PER, enabling the extending of two different amplification products: a long single-stranded DNA (ssDNA) with repetitive sequences and a short ferrocene-labeled ssDNA with complementary sequences. These products further self-assemble into DNA nano-strings in an orthogonal manner that act as an electrochemiluminescence signal switch, enabling precise detection of low-abundance UDG. This work develops a sequential input and orthogonal output strategy for accurately monitoring UDG activity, highlighting the significant potential in cancer diagnosis and treatment.

17.
Biochem Biophys Res Commun ; 730: 150339, 2024 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-39032359

RESUMEN

The tumor microenvironment (TME) assumes a pivotal role in the treatment of oncological diseases, given its intricate interplay of diverse cellular components and extracellular matrices. This dynamic ecosystem poses a serious challenge to traditional research methods in many ways, such as high research costs, inefficient translation, poor reproducibility, and low modeling success rates. These challenges require the search for more suitable research methods to accurately model the TME, and the emergence of 3D bioprinting technology is transformative and an important complement to these traditional methods to precisely control the distribution of cells, biomolecules, and matrix scaffolds within the TME. Leveraging digital design, the technology enables personalized studies with high precision, providing essential experimental flexibility. Serving as a critical bridge between in vitro and in vivo studies, 3D bioprinting facilitates the realistic 3D culturing of cancer cells. This comprehensive article delves into cutting-edge developments in 3D bioprinting, encompassing diverse methodologies, biomaterial choices, and various 3D tumor models. Exploration of current challenges, including limited biomaterial options, printing accuracy constraints, low reproducibility, and ethical considerations, contributes to a nuanced understanding. Despite these challenges, the technology holds immense potential for simulating tumor tissues, propelling personalized medicine, and constructing high-resolution organ models, marking a transformative trajectory in oncological research.


Asunto(s)
Bioimpresión , Impresión Tridimensional , Microambiente Tumoral , Humanos , Bioimpresión/métodos , Neoplasias/patología , Animales , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Andamios del Tejido/química
18.
Small ; 20(8): e2303834, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37867216

RESUMEN

A porous noncovalent organic framework with AIE effect is designed and synthesized as the support for gold nanoparticles (AuNPs). The framework is fabricated through the electrostatic complexation between carboxymethyl cellulose and tetraphenylethene-containing ammonium surfactant, which can complex AuNPs via the noncovalent interactions to offer a heterogeneous catalyst. Compared to the covalent modification on cellulose, this noncovalent framework gains superiorities in the catalyst synthesis and the size control of AuNPs. The AIE property and water-insolubility allow such heterogeneous catalysts to be easily detected, separated, and recycled, opening a new pathway for the reduction of nitrobenzene compounds and some dye compounds in aqueous conditions, which present the features of green chemistry. The use of cellulose for developing new heterogeneous metal catalysts, especially in a noncovalent way, would promote the value-added utilization of cellulose. This work provides a design strategy for gaining heterogeneous metal catalysts by taking advantage of natural bioresources.

19.
Small ; : e2404598, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291878

RESUMEN

The endowment of metal organic frameworks (MOF) with superior electrocatalytic performance without compromising their structural/compositional superiorities is of great significance for the development of renewable energy devices, yet remains a grand challenge. Herein, a deliberate partial amorphization strategy is developed to construct a heterostructured electrocatalyst consisting of crystalline Co-MOF and amorphous Co-S nanoflake arrays aligned on the carbon cloth (CC) substrate (abbreviated as Co-MOF/Co-S@CC hereafter) through a rapid sulfuration method. The simultaneous implement of crystalline-amorphous (c-a) heterostructure and nanoflake arrayed architecture on CC substrate renders the Co-MOF/Co-S@CC with abundant and tight active sites, accelerated charge transfer rate, regulated electronic structures, and reinforced structural stability. As such, the obtained Co-MOF/Co-S@CC electrode demonstrates outstanding electrochemical hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances with the overpotentials of 64 and 217 mV at 10 mA cm-2, respectively. Moreover, a two-electrode electrolyzer assembled by Co-MOF/Co-S@CC electrodes exhibits the lower cell voltages and larger current densities than those of Pt/C and RuO2 counterparts, excellent reversibility and prominent long-term stability, representing a great prospect for feasible H2 production. This adopted concept of c-a heterostructure for electronic regulation may bring about insightful inspiration for designing high-performance electrocatalysts for sustainable energy systems.

20.
J Med Virol ; 96(7): e29800, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39014958

RESUMEN

Globally, the rollout of COVID-19 vaccine had been faced with a significant barrier in the form of vaccine hesitancy. This study adopts a multi-stage perspective to explore the prevalence and determinants of COVID-19 vaccine hesitancy, focusing on their dynamic evolutionary features. Guided by the integrated framework of the 3Cs model (complacency, confidence, and convenience) and the EAH model (environmental, agent, and host), this study conducted three repeated national cross-sectional surveys. These surveys carried out from July 2021 to February 2023 across mainland China, targeted individuals aged 18 and older. They were strategically timed to coincide with three critical vaccination phases: universal coverage (stage 1), partial coverage (stage 2), and key population coverage (stage 3). From 2021 to 2023, the surveys examined sample sizes of 29 925, 6659, and 5407, respectively. The COVID-19 vaccine hesitation rates increased from 8.39% in 2021 to 29.72% in 2023. Urban residency, chronic condition, and low trust in vaccine developer contributed to significant COVID-19 vaccine hesitancy across the pandemic. Negative correlations between the intensity of vaccination policies and vaccine hesitancy, and positive correlations between vaccine hesitancy and long COVID, were confirmed. This study provides insights for designing future effective vaccination programs for emerging vaccine-preventable infectious X diseases.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Vacilación a la Vacunación , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , China/epidemiología , COVID-19/prevención & control , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , Estudios Transversales , Pueblos del Este de Asia , Encuestas y Cuestionarios , Vacunación/psicología , Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/estadística & datos numéricos , Vacilación a la Vacunación/psicología
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