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1.
Front Psychol ; 15: 1342318, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765831

RESUMO

Introduction: In the face of an increasingly challenging and rapidly evolving business environment, not all the employees exhibit the requisite resilience necessary to recover from adversity. From both the individual and organizational perspectives, enhancing employee resilience emerges as a critical issue not only in the practical and academic fields. In the Chinese culture, this research aims to investigate how and why collectivism-oriented human resource management (C-HRM) fosters employee resilience. Drawing on the group engagement model, we propose a serial mediating effect of perceived overall fairness and three dimensions of social identity between C-HRM and employee resilience. Methods: Using a sample of frontline employees in the hospitality industry, we conducted a field survey among 342 employees (study 1) and a two-wave online survey among 294 hospitality employees (study 2). Results: Findings from empirical analysis indicated that C-HRM significantly increases overall fairness perception of hospitality frontline employees and in turn, their identification and respect, which further fertilize employee resilience. In addition, the indirect effect of C-HRM on employee resilience through perceived overall fairness and pride was not statistically significant. Discussion: These important findings are expected to help employees cope with the workplace pressures caused by ongoing challenges and change, and contribute to sustainable career development.

2.
Chem Commun (Camb) ; 60(35): 4715-4718, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38596907

RESUMO

Chemically conjugated branched DNA was successfully synthesized by a copper-free click reaction to construct sophisticated and higher-order polyhedral DNA nanostructures with pre-defined units in one pot, which can be used as an efficient nanoplatform to precisely organize multiple gold nanoparticles in predesigned patterns.


Assuntos
DNA , Ouro , Nanopartículas Metálicas , Nanoestruturas , DNA/química , Ouro/química , Nanoestruturas/química , Nanopartículas Metálicas/química , Química Click , Tamanho da Partícula
3.
Med Phys ; 51(6): 4121-4132, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38452276

RESUMO

BACKGROUND: Ring artifact is a common problem in Computed Tomography (CT), which can lead to inaccurate diagnoses and treatment plans. It can be caused by various factors such as detector imperfections, anti-scatter grids, or other nonuniform filters placed in the x-ray beam. Physics-based corrections for these x-ray source and detector non-uniformity, in general cannot completely get rid of the ring artifacts. Therefore, there is a need for a robust method that can effectively remove ring artifacts in the image domain while preserving details. PURPOSE: This study aims to develop an effective method for removing ring artifacts from reconstructed CT images. METHODS: The proposed method starts by converting the reconstructed CT image containing ring artifacts into polar coordinates, thereby transforming these artifacts into stripes. Relative Total Variation is used to extract the image's overall structural information. For the efficient restoration of intricate details, we introduce Directional Gradient Domain Optimization (DGDO) and design objective functions that make use of both the image's gradient and its overall structure. Subsequently, we present an efficient analytical algorithm to minimize these objective functions. The image obtained through DGDO is then transformed back into Cartesian coordinates, finalizing the ring artifact correction process. RESULTS: Through a series of synthetic and real-world experiments, we have effectively demonstrated the prowess of our proposed method in the correction of ring artifacts while preserving intricate details in reconstructed CT images. In a direct comparison, our method has exhibited superior visual quality compared to several previous approaches. These results underscore the remarkable potential of our approach for enhancing the overall quality and clinical utility of CT imaging. CONCLUSIONS: The proposed method offers an analytical solution for removing ring artifacts from CT images while preserving details. As ring artifacts are a common problem in CT imaging, this method has high practical value in the medical field. The proposed method can improve image quality and reduce the difficulty of disease diagnosis, thereby contributing to better patient care.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Imagens de Fantasmas , Humanos
4.
Angew Chem Int Ed Engl ; 63(13): e202317334, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38323479

RESUMO

Xeno-nucleic acids (XNAs) are synthetic genetic polymers with improved biological stabilities and offer powerful molecular tools such as aptamers and catalysts. However, XNA application has been hindered by a very limited repertoire of tool enzymes, particularly those that enable de novo XNA synthesis. Here we report that terminal deoxynucleotide transferase (TdT) catalyzes untemplated threose nucleic acid (TNA) synthesis at the 3' terminus of DNA oligonucleotide, resulting in DNA-TNA chimera resistant to exonuclease digestion. Moreover, TdT-catalyzed TNA extension supports one-pot batch preparation of biostable chimeric oligonucleotides, which can be used directly as staple strands during self-assembly of DNA origami nanostructures (DONs). Such TNA-protected DONs show enhanced biological stability in the presence of exonuclease I, DNase I and fetal bovine serum. This work not only expands the available enzyme toolbox for XNA synthesis and manipulation, but also provides a promising approach to fabricate DONs with improved stability under the physiological condition.


Assuntos
Nanoestruturas , Naftalenossulfonatos , Ácidos Nucleicos , Tetroses , Ácidos Nucleicos/química , Oligonucleotídeos/química , DNA Polimerase Dirigida por DNA , DNA Nucleotidilexotransferase , Polímeros , DNA/química
5.
J Am Chem Soc ; 146(6): 4178-4186, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38301245

RESUMO

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.


Assuntos
Nanoestruturas , Nanoestruturas/química , Nanotecnologia , DNA/química , Análise de Sequência com Séries de Oligonucleotídeos , Conformação de Ácido Nucleico
6.
Nat Commun ; 14(1): 6993, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914731

RESUMO

Adult skeletal muscle regeneration is mainly driven by muscle stem cells (MuSCs), which are highly heterogeneous. Although recent studies have started to characterize the heterogeneity of MuSCs, whether a subset of cells with distinct exists within MuSCs remains unanswered. Here, we find that a population of MuSCs, marked by Gli1 expression, is required for muscle regeneration. The Gli1+ MuSC population displays advantages in proliferation and differentiation both in vitro and in vivo. Depletion of this population leads to delayed muscle regeneration, while transplanted Gli1+ MuSCs support muscle regeneration more effectively than Gli1- MuSCs. Further analysis reveals that even in the uninjured muscle, Gli1+ MuSCs have elevated mTOR signaling activity, increased cell size and mitochondrial numbers compared to Gli1- MuSCs, indicating Gli1+ MuSCs are displaying the features of primed MuSCs. Moreover, Gli1+ MuSCs greatly contribute to the formation of GAlert cells after muscle injury. Collectively, our findings demonstrate that Gli1+ MuSCs represents a distinct MuSC population which is more active in the homeostatic muscle and enters the cell cycle shortly after injury. This population functions as the tissue-resident sentinel that rapidly responds to injury and initiates muscle regeneration.


Assuntos
Doenças Musculares , Células Satélites de Músculo Esquelético , Humanos , Músculo Esquelético/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Diferenciação Celular
7.
J Am Chem Soc ; 145(41): 22442-22455, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37791901

RESUMO

In 2015, we reported a photochemical method for directed C-C bond cleavage/radical fluorination of relatively unstrained cyclic acetals using Selectfluor and catalytic 9-fluorenone. Herein, we provide a detailed mechanistic study of this reaction, during which it was discovered that the key electron transfer step proceeds through substrate oxidation from a Selectfluor-derived N-centered radical intermediate (rather than through initially suspected photoinduced electron transfer). This finding led to proof of concept for two new methodologies, demonstrating that unstrained C-C bond fluorination can also be achieved under chemical and electrochemical conditions. Moreover, as C-C and C-H bond fluorination reactions are both theoretically possible on 2-aryl-cycloalkanone acetals and would involve the same reactive intermediate, we studied the competition between single-electron transfer (SET) and apparent hydrogen-atom transfer (HAT) pathways in acetal fluorination reactions using density functional theory. Finally, these analyses were applied more broadly to other classes of C-H and C-C bond fluorination reactions developed over the past decade, addressing the feasibility of SET processes masquerading as HAT in C-H fluorination literature.

8.
Angew Chem Int Ed Engl ; 62(51): e202315093, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37906116

RESUMO

DNA nanostructures have played an important role in the development of novel drug delivery systems. Herein, we report a DNA origami-based CRISPR/Cas9 gene editing system for efficient gene therapy in vivo. In our design, a PAM-rich region precisely organized on the surface of DNA origami can easily recruit and load sgRNA/Cas9 complex by PAM-guided assembly and pre-designed DNA/RNA hybridization. After loading the sgRNA/Cas9 complex, the DNA origami can be further rolled up by the locking strands with a disulfide bond. With the incorporation of DNA aptamer and influenza hemagglutinin (HA) peptide, the cargo-loaded DNA origami can realize the targeted delivery and effective endosomal escape. After reduction by GSH, the opened DNA origami can release the sgRNA/Cas9 complex by RNase H cleavage to achieve a pronounced gene editing of a tumor-associated gene for gene therapy in vivo. This rationally developed DNA origami-based gene editing system presents a new avenue for the development of gene therapy.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas , Terapia Genética , DNA/genética
9.
Theranostics ; 13(11): 3761-3780, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441604

RESUMO

Rationale: Sepsis is a potentially life-threatening condition caused by the body's response to a severe infection. Although the identification of multiple pathways involved in inflammation, tissue damage and aberrant healing during sepsis, there remain unmet needs for the development of new therapeutic strategies essential to prevent the reoccurrence of infection and organ injuries. Methods: Expression of Suppressor of Fused (Sufu) was evaluated by qRT-PCR, western blotting, and immunofluorescence in murine lung and peritoneal macrophages. The significance of Sufu expression in prognosis was assessed by Kaplan-Meier survival analysis. The GFP-TRAF6-expressing stable cell line (GFP-TRAF6 Blue cells) were constructed to evaluate phase separation of TRAF6. Phase separation of TRAF6 and the roles of Sufu in repressing TRAF6 droplet aggregation were analyzed by co-immunoprecipitation, immunofluorescence, Native-PAGE, FRAP and in vitro assays using purified proteins. The effects of Sufu on sepsis-induced lung inflammation were evaluated by cell function assays, LPS-induced septic shock model and polymicrobial sepsis-CLP mice model. Results: We found that Sufu expression is reduced in early response to lipopolysaccharide (LPS)-induced acute inflammation in murine lung and peritoneal macrophages. Deletion of Sufu aggravated LPS-induced and CLP (cecal ligation puncture)-induced lung injury and lethality in mice, and augmented LPS-induced proinflammatory gene expression in cultured macrophages. In addition, we identified the role of Sufu as a negative regulator of the Toll-Like Receptor (TLR)-triggered inflammatory response. We further demonstrated that Sufu directly interacts with TRAF6, thereby preventing oligomerization and autoubiquitination of TRAF6. Importantly, TRAF6 underwent phase separation during LPS-induced inflammation, which is essential for subsequent ubiquitination activation and NF-κB activity. Sufu inhibits the phase-separated TRAF6 droplet formation, preventing NF-κB activation upon LPS stimulation. In a septic shock model, TRAF6 depletion rescued the augmented inflammatory phenotype in mice with myeloid cell-specific deletion of Sufu. Conclusions: These findings implicated Sufu as an important inhibitor of TRAF6 in sepsis and suggest that therapeutics targeting Sufu-TRAF6 may greatly benefit the treatment of sepsis.


Assuntos
Pneumonia , Sepse , Choque Séptico , Camundongos , Animais , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF , Lipopolissacarídeos/farmacologia , Inflamação , Sepse/tratamento farmacológico
10.
Org Lett ; 25(23): 4318-4322, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37279142

RESUMO

We have found that face-to-face π-stacked aromatic rings show the propensity to activate one another toward electrophilic aromatic substitution through direct influence of the probe aromatic ring by the adjacent stacked ring, rather than through the formation of relay or "sandwich complexes." This activation remains in force even when one of the rings is deactivated through nitration. The resulting dinitrated products are shown to crystallize in an extended parallel offset stacked form, in stark contrast to the substrate.

11.
J Org Chem ; 88(4): 2557-2560, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36702475

RESUMO

Electrosynthesis has made a revival in the field of organic chemistry and, in particular, radical-mediated reactions. Herein, we report a simple directed, electrochemical C-H fluorination method. Employing a dabconium mediator, commercially available Selectfluor, and RVC electrodes, we provide a range of steroid-based substrates with competent regioselective directing groups, including enones, ketones, and hydroxy groups, as well as never reported before lactams, imides, lactones, and esters.

12.
Cell Discov ; 9(1): 11, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693846

RESUMO

Chromosomes occupy discrete spaces in the interphase cell nucleus, called chromosome territory. The structural and functional relevance of chromosome territory remains elusive. We fused chromosome 15 and 17 in mouse haploid embryonic stem cells (haESCs), resulting in distinct changes of territories in the cognate chromosomes, but with little effect on gene expression, pluripotency and gamete functions of haESCs. The karyotype-engineered haESCs were successfully implemented in generating heterozygous (2n = 39) and homozygous (2n = 38) mouse models. Mice containing the fusion chromosome are fertile, and their representative tissues and organs display no phenotypic abnormalities, suggesting unscathed development. These results indicate that the mammalian chromosome architectures are highly resilient, and reorganization of chromosome territories can be readily tolerated during cell differentiation and mouse development.

13.
IEEE Trans Pattern Anal Mach Intell ; 45(6): 7726-7738, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36409815

RESUMO

We present a novel method for local image feature matching. Instead of performing image feature detection, description, and matching sequentially, we propose to first establish pixel-wise dense matches at a coarse level and later refine the good matches at a fine level. In contrast to dense methods that use a cost volume to search correspondences, we use self and cross attention layers in Transformer to obtain feature descriptors that are conditioned on both images. The global receptive field provided by Transformer enables our method to produce dense matches in low-texture areas, where feature detectors usually struggle to produce repeatable interest points. The experiments on indoor and outdoor datasets show that LoFTR outperforms state-of-the-art methods by a large margin. We further adapt LoFTR to modern SfM systems and illustrate its application in multiple-view geometry. The proposed method demonstrates superior performance in Image Matching Challenge 2021 and ranks first on two public benchmarks of visual localization among the published methods. The code is available at https://zju3dv.github.io/loftr.

14.
ISA Trans ; 127: 68-79, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35428476

RESUMO

This article focuses on the partial-nodes-based state estimation (PNBSE) issue for a complex network with the encoding-decoding mechanism (EDM) over the unreliable communication channel, where the signals are transmitted in an intermittent manner. A so-called EDM is exploited to convert the transmitted signals into a set of codewords with finite bits so as to facilitate the transmission efficiency between the complex networks and the estimator. To guarantee the state estimation (SE) performance subject to the intermittent communication nature of the channel, a buffer with limited capacity, which stores the recent measurement signals and sends them to the estimator simultaneously, is adopted to improve the utilization rate of the measurement signals in the estimation process. The main objective of the investigated problem is to construct a partial-nodes-based (PNB) estimator to generate the desired state estimates for the underlying complex networks. Considering the intermittent feature of signal transmission, the ultimate boundedness of the SE error under the constructed PNB estimator is discussed, and then, sufficient conditions are derived which ensure that the desired PNB estimator exists. An simulation example is given to confirm the correctness and effectiveness of the proposed estimator design strategy in the end.

15.
Bioresour Technol ; 351: 126968, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35276372

RESUMO

Nitrogen has a vital influence on the properties of the microwave-assisted hydrothermal carbonization (MHTC) products of Spirulina platensis (SP). The effects of hydrothermal temperature (140-220 °C) and time (1-4 h) on the product distribution and nitrogen migration of SP in MHTC were studied. Increasing temperature led to an increase in the carbon content, and a decrease in the nitrogen content in hydrochar. Protein-N was the major nitrogen-containing species in hydrochar. The total nitrogen in liquid phase increased significantly with increasing temperature. Carbon dots were found to be one of the valuable products in the liquid phase. Higher temperatures improved the amine-N level and reduced the quaternary-N content in carbon dots. A close correspondence was found between the N-containing species and the luminescence centers of carbon dots. A possible nitrogen migration mechanism was proposed to provide guidance for the potential application of the products.


Assuntos
Nitrogênio , Spirulina , Carbono , Micro-Ondas , Temperatura
16.
Innovation (Camb) ; 3(2): 100217, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35243471

RESUMO

Based on predictable, complementary base pairing, DNA can be artificially pre-designed into versatile DNA nanostructures of well-defined shapes and sizes. With excellent addressability and biocompatibility, DNA nanostructures have been widely employed in biomedical research, such as bio-sensing, bio-imaging, and drug delivery. With the development of the chemical biology of nucleic acid, chemically modified nucleic acids are also gradually developed to construct multifunctional DNA nanostructures. In this review, we summarize the recent progress in the construction and functionalization of chemically modified DNA nanostructures. Their applications in the delivery of chemotherapeutic drugs and nucleic acid drugs are highlighted. Furthermore, the remaining challenges and future prospects in drug delivery by chemically modified DNA nanostructures are discussed.

17.
Int J Stroke ; 17(4): 425-433, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33739197

RESUMO

BACKGROUND: Remote ischemic conditioning can promote hematoma resolution, attenuate brain edema, and improve neurological recovery in animal models of intracerebral hemorrhage. AIMS: This study aimed to evaluate the safety and preliminary efficacy of remote ischemic conditioning in patients with intracerebral hemorrhage. METHODS: In this multicenter, randomized, controlled trial, 40 subjects with supratentorial intracerebral hemorrhage presenting within 24-48 h of onset were randomly assigned to receive medical therapy plus remote ischemic conditioning for consecutive seven days or medical therapy alone. The primary safety outcome was neurological deterioration within seven days of enrollment, and the primary efficacy outcome was the changes of hematoma volume on CT images. Other outcomes included hematoma resolution rate at 7 days ([hematoma volume at 7 days - hematoma volume at baseline]/hematoma volume at baseline), perihematomal edema (PHE), and functional outcome at 90 days. RESULTS: The mean age was 59.3 ± 11.7 years and hematoma volume was 13.9 ± 4.5 mL. No subjects experienced neurological deterioration within seven days of enrollment, and no subject died or experienced remote ischemic conditioning-associated adverse events during the study period. At baseline, the hematoma volumes were 14.19 ± 5.07 mL in the control group and 13.55 ± 3.99 mL in the remote ischemic conditioning group, and they were 8.54 ± 3.99 mL and 6.95 ± 2.71 mL at seven days after enrollment, respectively, which is not a significant difference (p > 0.05 each). The hematoma resolution rate in the remote ischemic conditioning group (49.25 ± 9.17%) was significantly higher than in the control group (41.92 ± 9.14%; MD, 7.3%; 95% CI, 1.51-13.16%; p = 0.015). The absolute PHE volume was 17.27 ± 8.34 mL in the control group and 12.92 ± 7.30 mL in the remote ischemic conditioning group at seven days after enrollment, which is not a significant between-group difference (p = 0.087), but the relative PHE in the remote ischemic conditioning group (1.77 ± 0.39) was significantly lower than in the control group (2.02 ± 0.27; MD, 0.25; 95% CI, 0.39-0.47; p = 0.023). At 90-day follow-up, 13 subjects (65%) in the remote ischemic conditioning group and 12 subjects (60%) in the control group achieved favorable functional outcomes (modified Rankin Scale score ≤ 3), which is not a significant between-group difference (p = 0.744). CONCLUSIONS: Repeated daily remote ischemic conditioning for consecutive seven days was safe and well tolerated in patients with intracerebral hemorrhage, and it may be able to improve hematoma resolution rate and reduce relative PHE. However, the effects of remote ischemic conditioning on the absolute hematoma and PHE volume and functional outcomes in this patient population need further investigations.Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03930940.


Assuntos
Edema Encefálico , Acidente Vascular Cerebral , Edema Encefálico/etiologia , Edema Encefálico/terapia , Hemorragia Cerebral/tratamento farmacológico , Hematoma/terapia , Humanos , Resultado do Tratamento
18.
Nat Metab ; 3(11): 1569-1584, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34750570

RESUMO

The Hedgehog (Hh) signalling pathway plays a critical role in regulating liver lipid metabolism and related diseases. However, the underlying mechanisms are poorly understood. Here, we show that the Hh signalling pathway induces a previously undefined long non-coding RNA (Hilnc, Hedgehog signalling-induced long non-coding RNA), which controls hepatic lipid metabolism. Mutation of the Gli-binding sites in the Hilnc promoter region (HilncBM/BM) decreases the expression of Hilnc in vitro and in vivo. HilncBM/BM and Hilnc-knockout mice are resistant to diet-induced obesity and hepatic steatosis through attenuation of the peroxisome proliferator-activated receptor signalling pathway, as Hilnc directly interacts with IGF2BP2 to enhance Pparγ mRNA stability. Furthermore, we identify a potential functional human homologue of Hilnc, h-Hilnc, which has a similar function in regulating cellular lipid metabolism. These findings uncover a critical role of the Hh-Hilnc-IGF2BP2 signalling axis in lipid metabolism and suggest a potential therapeutic target for the treatment of diet-induced hepatic steatosis.


Assuntos
Dieta Hiperlipídica , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , RNA Longo não Codificante/genética , Animais , Biomarcadores , Linhagem Celular , Suscetibilidade a Doenças , Fígado Gorduroso/patologia , Expressão Gênica , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Marcação de Genes , Proteínas Hedgehog/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Obesidade/complicações , Obesidade/etiologia , Obesidade/metabolismo , PPAR gama/metabolismo , Ligação Proteica , Proteínas de Ligação a RNA , Transdução de Sinais
19.
ACS Appl Bio Mater ; 4(10): 7701-7707, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-35006686

RESUMO

DNA-based nanogels have attracted much attention in the biomedical research field. Herein, we report a universal strategy for the fabrication of an aptamer-modified DNA tetrahedron (TET)-based nanogel for combined chemo/gene therapy of multidrug-resistant tumors. In our design, terminal extended antisense oligonucleotides (ASOs) are employed as the linker to co-assemble with two kinds of three-vertex extended TETs for the efficient construction of the DNA-based nanogel. With the incorporation of an active cell-targeting group (aptamer in one vertex of TET) and a controlled-release element (disulfide bridges in the terminals of ASOs), the functional DNA-based nanogel can achieve targeted cellular internalization and stimuli-responsive release of embedded ASOs. After loading with the chemodrug (doxorubicin (DOX), an intercalator of double-stranded DNA), the multifunctional DOX/Nanogel elicits efficient chemo/gene therapy of human MCF-7 breast tumor cells with DOX resistance (MCF-7R). This aptamer-modified DNA tetrahedron-based nanogel provides another strategy for intelligent drug delivery and combined tumor therapy.


Assuntos
DNA , Doxorrubicina , Doxorrubicina/farmacologia , Terapia Genética , Humanos , Nanogéis , Oligonucleotídeos Antissenso , Polietilenoglicóis , Polietilenoimina
20.
Entropy (Basel) ; 22(5)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-33286346

RESUMO

Underwater quantumkey distribution (QKD) is tough but important formodern underwater communications in an insecure environment. It can guarantee secure underwater communication between submarines and enhance safety for critical network nodes. To enhance the performance of continuous-variable quantumkey distribution (CVQKD) underwater in terms ofmaximal transmission distance and secret key rate as well, we adopt measurement-device-independent (MDI) quantum key distribution with the zero-photon catalysis (ZPC) performed at the emitter of one side, which is the ZPC-based MDI-CVQKD. Numerical simulation shows that the ZPC-involved scheme, which is a Gaussian operation in essence, works better than the single photon subtraction (SPS)-involved scheme in the extreme asymmetric case. We find that the transmission of the ZPC-involved scheme is longer than that of the SPS-involved scheme. In addition, we consider the effects of temperature, salinity and solar elevation angle on the system performance in pure seawater. The maximal transmission distance decreases with the increase of temperature and the decrease of sunlight elevation angle, while it changes little over a broad range of salinity.

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