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1.
Nat Commun ; 15(1): 7771, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237528

RESUMO

Alkaline metal sulfur (AMS) batteries offer a promising solution for grid-level energy storage due to their low cost and long cycle life. However, the formation of solid compounds such as M2S2 and M2S (M = Na, K) during cycling limits their performance. Here we unveil intermediate-temperature K-Na/S batteries utilizing advanced electrolytes that dissolve all polysulfides and sulfides (K2Sx, x = 1-8), significantly enhancing reaction kinetics, specific capacity, and energy density. These batteries achieve near-theoretical capacity (1655 mAh g-1 sulfur) at 75 °C with a 1 M sulfur concentration. At a 4 M sulfur concentration, they deliver 830 mAh g-1 at 2 mA cm-2, retaining 71% capacity after 1000 cycles. This new K-Na/S battery with specific energy of 150-250 Wh kg-1 only employs earth-abundant elements, making it attractive for long-duration energy storage.

2.
Opt Express ; 32(10): 17499-17513, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858932

RESUMO

Over years of space laser communication technology advances, satellite optical networks (SONs) have emerged as a pivotal component in 6 G networks. Satellite services are transmitted from the global view, undergoing transmission through SONs, and being downloaded to the targeted areas. However, the transmission capacity of satellites passing through the areas where users are concentrated may be insufficient to download services transmitted worldwide. This problem exists in various kinds of satellite networks and may cause a large amount of service congestion. In this paper, we propose a multi-downlink delivery routing selection (MDD-RS) strategy to study the total utilization of transmission capacity of SONs. We construct an integer linear programming (ILP) model to establish an optimal case study for minimal network capacity occupation. Also, we design an online option, MDD-RS heuristic algorithm, dynamically calculating path routes, considering bandwidth allocation and resource constraints. A comparative analysis against the conventional single-downlink scheme reveals superior performance of the MDD-RS heuristic algorithm, with a reduction in blocking probability of 0.129 and an improvement in bandwidth utilization of 0.032.

3.
iScience ; 26(12): 108466, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38077137

RESUMO

Direct cardiac reprogramming to induce cardiomyocyte-like cells, e.g., by GMT (Gata4, Mef2c and Tbx5), is a promising route for regenerating damaged heart in vivo and disease modeling in vitro. Supplementation with additional factors and chemical agents can enhance efficiency but raises concerns regarding selectivity to cardiac fibroblasts and complicates delivery for in situ cardiac reprogramming. Here, we screened 2000 chemicals with known biological activities and found that a combination of 2C (SB431542 and Baricitinib) significantly enhances cardiac reprogramming by GMT. Without Gata4, MT (Mef2c and Tbx5) plus 2C could selectively reprogram cardiac fibroblasts with enhanced efficiency, kinetics, and cardiomyocyte function. Moreover, 2C significantly enhanced cardiac reprogramming in human cardiac fibroblasts. 2C synergistically enhances cardiac reprogramming by inhibiting Alk5, Tyk2 and downregulating Oas2, Oas3, Serpina3n and Tgfbi. 2C enables selective and robust cardiac reprogramming that can greatly facilitate disease modeling in vitro and advance clinical therapeutic heart regeneration in vivo.

4.
J Colloid Interface Sci ; 652(Pt B): 1108-1116, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657211

RESUMO

Due to the high selectivity and non-invasive property, phototherapy has attracted increasing attention in the treatment of cancer. Targeted delivery and retention of photoactive agents in tumor tissue is of great significance and importance for safe and efficient phototherapy. Herein, we report a multifunctional nanomaterial photothermal agent, namely amino-modified graphene oxide (AGO) for anti-oral cancer photothermal therapy (PTT). Compared to the parental graphene oxide (GO) which has a negative charge and weak photothermal effect, AGO possesses a positive charge (∼+50 mV) and the significantly enhanced photothermal effect. Positive charge allows AGO to efficiently interact with tumor cells and retain in tumor tissue after intratumor injection. The enhanced photothermal effect allows AGO to achieve the tunable and efficient PTT. In vitro results show that AGO (15 µg/mL) reduces the viability of HSC-3 cells (oral squamous cell carcinoma cell line) to 5% under near infrared (NIR) irradiation (temperature increased to 58.4 °C). In vivo antitumor study shows that intratumor delivery of AGO (200 µg/mouse) has no inhibition effects on tumor growth (454% of initial tumor size) without NIR. With a single dose of NIR irradiation, however, AGO significantly reduces the tumor size to 25% of initial size in 1 of 4 mice, and even induces the complete tumor ablation in 3 of 4 mice. Furthermore, the injected AGO falls off along with the scab after PTT. Our findings indicate that AGO is a potential nano-photothermal agent for tunable, convenient and efficient anticancer PTT.

5.
Opt Express ; 31(5): 8682-8695, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859978

RESUMO

Low earth orbit satellite laser communication has become an important part of communications due to its large capacity and low latency. The lifetime of the satellite mainly depends on the recharge and discharge cycles of the battery. The low earth orbit satellites frequently recharge under sunlight and discharge in the shadow, which leads satellites to age quickly. This paper studies the energy-efficient routing problem for satellite laser communication and builds the satellite ageing model. Based on the model, we propose an energy-efficient routing scheme based on the genetic algorithm. Compared with shortest path routing, the proposed method improves the satellite lifetime by about 300%, and the performances of the network are only slightly degraded, the blocking ratio increases by only 1.2%, and the service delay increases by 1.3 ms.

6.
Hepatology ; 77(5): 1550-1565, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35881538

RESUMO

BACKGROUND AND AIMS: Cell fate can be directly reprogrammed from accessible cell types (e.g., fibroblasts) into functional cell types by exposure to small molecule stimuli. However, no chemical reprogramming method has been reported to date that successfully generates functional hepatocyte-like cells that can repopulate liver tissue, casting doubt over the feasibility of chemical reprogramming approaches to obtain desirable cell types for therapeutic applications. APPROACH AND RESULTS: Here, through chemical induction of phenotypic plasticity, we provide a proof-of-concept demonstration of the direct chemical reprogramming of mouse fibroblasts into functional hepatocyte-like cells using exposure to small molecule cocktails in culture medium to successively stimulate endogenous expression of master transcription factors associated with hepatocyte development, such as hepatocyte nuclear factor 4a, nuclear receptor subfamily 1, group I, member 2, and nuclear receptor subfamily 1, group H, member 4. RNA sequencing analysis, metabolic assays, and in vivo physiological experiments show that chemically induced hepatocytes (CiHeps) exhibit comparable activity and function to primary hepatocytes, especially in liver repopulation to rescue liver failure in fumarylacetoacetate hydrolase -/- recombination activating gene 2 -/- interleukin 2 receptor, gamma chain -/- mice in vivo . Single-cell RNA-seq further revealed that gastrointestinal-like and keratinocyte-like cells were induced along with CiHeps, resembling the activation of an intestinal program within hepatic reprogramming as described in transgenic approaches. CONCLUSIONS: Our findings show that direct chemical reprogramming can generate hepatocyte-like cells with high-quality physiological properties, providing a paradigm for establishing hepatocyte identity in fibroblasts and demonstrating the potential for chemical reprogramming in organ/tissue repair and regeneration therapies.


Assuntos
Hepatócitos , Fígado , Animais , Camundongos , Fígado/metabolismo , Hepatócitos/metabolismo , Diferenciação Celular , Células Cultivadas , Fatores de Transcrição/metabolismo , Reprogramação Celular
7.
Microbiol Res ; 261: 127082, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35660471

RESUMO

In the past, tumor and microbial infection were commonly regarded as independent diseases with few interrelations. The discovery of bacteria in tumor tissue changed the knowledge of bacteria-tumor relationship. Recently, more and more findings have demonstrated the significant effects of bacteria on the genesis, development and metastasis of tumor. Particularly, the influence of bacteria on tumor immunity is of great interest. Bacteria can inhibit the function of immune system through multiple mechanisms. On the other hand, some bacteria can also enhance the immune response and inhibit tumor progression. Understanding the bacteria-tumor interactions is of great importance for developing novel anticancer approaches. Herein, we aim to provide a comprehensive understanding of the tumor/tumor immunology, the biogenesis of bacteria in tumor and the relation of tumorigenesis with bacteria. In addition, the roles of bacteria in tumor immunology and the potential approaches to use bacteria for cancer therapy are discussed.


Assuntos
Neoplasias , Bactérias/genética , Humanos , Imunidade
8.
Front Cell Dev Biol ; 10: 865038, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399519

RESUMO

Somatic cells can be chemically reprogrammed into a pluripotent stem cell (CiPSC) state, mediated by an extraembryonic endoderm- (XEN-) like state. We found that the chemical cocktail applied in CiPSC generation initially activated a plastic state in mouse fibroblasts before transitioning into XEN-like cells. The plastic state was characterized by broadly activated expression of development-associated transcription factors (TFs), such as Sox17, Ascl1, Tbx3, and Nkx6-1, with a more accessible chromatin state indicating an enhanced capability of cell fate conversion. Intriguingly, introducing such a plastic state remarkably improved the efficiency of chemical reprogramming from fibroblasts to functional neuron-like cells with electrophysiological activity or beating skeletal muscles. Furthermore, the generation of chemically induced neuron-like cells or skeletal muscles from mouse fibroblasts was independent of the intermediate XEN-like state or the pluripotency state. In summary, our findings revealed a plastic chemically activated multi-lineage priming (CaMP) state at the onset of chemical reprogramming. This state enhanced the cells' potential to adapt to other cell fates. It provides a general approach to empowering chemical reprogramming methods to obtain functional cell types bypassing inducing pluripotent stem cells.

9.
Biomed Res Int ; 2021: 3278351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34532500

RESUMO

Recent studies have supported the relationship between periodontitis and carotid artery calcification (CAC), but still uncertain. This systematic review is aimed at evaluating the association between periodontitis and CAC. The search was conducted in four electronic databases: PubMed, EMBASE, Web of Science, and The Cochrane Library, supplemented by checking references of included articles and related review articles. Eligibility assessment and data extraction were conducted independently. The quality assessment and publication bias analysis were performed. The association between periodontitis and CAC was presented in odd ratio (OR) with 95% confidence interval (CI). Additional outcomes included the percentage of alveolar bone loss in CAC versus non-CAC. Twelve studies were included, and 10 were performed quantity analysis. Periodontitis with secure definition (OR = 2.02, 95%CI = 1.18 - 3.45) and insecure definition (OR = 10.78, 95%CI = 4.41 - 26.34) was associated with CAC. And a higher average percentage of alveolar bone loss (weighted mean difference = 10.84%; 95%CI = 6.40 - 15.48) was also observed in CAC patients compared to non-CAC patients. No significant publication bias was found. The results of this systematic review and meta-analysis revealed a significant relationship between periodontitis and CAC.


Assuntos
Calcinose/fisiopatologia , Artérias Carótidas/fisiopatologia , Artropatias/fisiopatologia , Periodontite/fisiopatologia , Doenças Vasculares/fisiopatologia , Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Humanos , Razão de Chances , Periodontite/metabolismo , Medição de Risco/métodos , Fatores de Risco
10.
Commun Biol ; 3(1): 629, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33128002

RESUMO

Mouse somatic cells can be chemically reprogrammed into pluripotent stem cells (CiPSCs) through an intermediate extraembryonic endoderm (XEN)-like state. However, it is elusive how the chemicals orchestrate the cell fate alteration. In this study, we analyze molecular dynamics in chemical reprogramming from fibroblasts to a XEN-like state. We find that Sox17 is initially activated by the chemical cocktails, and XEN cell fate specialization is subsequently mediated by Sox17 activated expression of other XEN master genes, such as Sall4 and Gata4. Furthermore, this stepwise process is differentially regulated. The core reprogramming chemicals CHIR99021, 616452 and Forskolin are all necessary for Sox17 activation, while differently required for Gata4 and Sall4 expression. The addition of chemical boosters in different phases further improves the generation efficiency of XEN-like cells. Taken together, our work demonstrates that chemical reprogramming is regulated in 3 distinct "prime-specify-transit" phases initiated with endogenous Sox17 activation, providing a new framework to understand cell fate determination.


Assuntos
Reprogramação Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Proteínas HMGB/metabolismo , Fatores de Transcrição SOXF/metabolismo , Fatores de Transcrição/genética , Adenosina/análogos & derivados , Adenosina/farmacologia , Animais , Benzoatos/farmacologia , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem da Célula , Reprogramação Celular/fisiologia , Chalconas/farmacologia , Colforsina/farmacologia , Endoderma/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas HMGB/genética , Camundongos Endogâmicos ICR , Compostos de Fenilureia/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Fatores de Transcrição SOXF/genética , Análise de Célula Única/métodos , Tetra-Hidronaftalenos/farmacologia
11.
Adv Mater ; 32(8): e1906722, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31957092

RESUMO

The development of Li-S batteries is largely impeded by the growth of Li dendrites and polysulfide shuttling. To solve these two problems simultaneously, herein the study reports a "single atom array mimic" on ultrathin metal organic framework (MOF) nanosheet-based bifunctional separator for achieving the highly safe and long life Li-S batteries. In the designed separator, the periodically arranged cobalt atoms coordinated with oxygen atoms (CoO4 moieties) exposed on the surface of ultrathin MOF nanosheets, "single atom array mimic", can greatly homogenize Li ion flux through the strong Li ion adsorption with O atoms at the interface between anode and separator, leading to stable Li striping/plating. Meantime, at the cathode side, the Co single atom array mimic serves as "traps" to suppress polysulfide shuttling by Lewis acid-base interaction. As a result, the Li-S coin cells with the bifunctional separator exhibit a long cycle life with an ultralow capacity decay of 0.07% per cycle over 600 cycles. Even with a high sulfur loading of 7.8 mg cm-2 , an areal capacity of 5.0 mAh cm-2 can be remained after 200 cycles. Moreover, the assembled Li-S pouch cell displays stable cycling performance under various bending angles, demonstrating the potential for practical applications.

12.
Dalton Trans ; 47(7): 2285-2291, 2018 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-29363695

RESUMO

With a 4-aminostyryl group introduced at its 3-position, a BODIPY BDP-ODTAC was derived as a new ratiometric sensor for Ag+ by modifying 4-amino group as a Ag+ chelator, 1-oxa-4,10-dithia-7-azacyclododecane (ODTAC). In addition to the specific Ag+-induced hypsochromic absorption shift from 606 to 562 nm, this sensor demonstrated an excitation shift from 600 to 560 nm due to the internal charge transfer (ICT) effect endowed by the introduced α-4-aminostyryl group. The Ag+-induced recovery and enhancement of the intrinsic local emission band was also observed. The different sensing behavior of ODTAC-BDP with chelator ODTAC substituting on the meso-phenyl group infers that the ratiometric sensing behavior of BDP-ODTAC is correlated to the amino group in ODTAC acting as the electron donor for the ICT effect. With high Ag+ selectivity over interfering cations such as Hg2+ and Pb2+, BDP-ODTAC displays a fluorometric limit of detection (LOD) of ∼17 nM (∼0.002 ppm), which is distinctly lower than EPA and WHO standards for drinking water (500 nM, ∼0.055 ppm). Moreover, the BDP-ODTAC-doped PVC film shows the Ag+ sensitivity of 1 ppm with a color switch from blue to purple, providing this sensor the ability to determine Ag+ in totally aqueous solution sensitively via naked-eye detection.

13.
Nat Commun ; 8: 14639, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28256511

RESUMO

Endothelial exocytosis of Weibel-Palade body (WPB) is one of the first lines of defence against vascular injury. However, the mechanisms that control WPB exocytosis in the final stages (including the docking, priming and fusion of granules) are poorly understood. Here we show that the focal adhesion protein zyxin is crucial in this process. Zyxin downregulation inhibits the secretion of von Willebrand factor (VWF), the most abundant cargo in WPBs, from human primary endothelial cells (ECs) induced by cAMP agonists. Zyxin-deficient mice exhibit impaired epinephrine-stimulated VWF release, prolonged bleeding time and thrombosis, largely due to defective endothelial secretion of VWF. Using live-cell super-resolution microscopy, we visualize previously unappreciated reorganization of pre-existing actin filaments around WPBs before fusion, dependent on zyxin and an interaction with the actin crosslinker α-actinin. Our findings identify zyxin as a physiological regulator of endothelial exocytosis through reorganizing local actin network in the final stage of exocytosis.


Assuntos
Citoesqueleto de Actina/metabolismo , Células Endoteliais/metabolismo , Exocitose/fisiologia , Zixina/fisiologia , Fator de von Willebrand/metabolismo , Actinina/metabolismo , Animais , Tempo de Sangramento , Colforsina/farmacologia , AMP Cíclico/agonistas , Células Endoteliais/efeitos dos fármacos , Epinefrina/farmacologia , Exocitose/efeitos dos fármacos , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Microscopia Intravital , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Trombose/patologia , Corpos de Weibel-Palade/metabolismo
15.
Org Biomol Chem ; 10(26): 5073-6, 2012 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-22627395

RESUMO

A hybrid coumarin-hemicyanine dye, Cou-BT, was developed as a new ratiometric and colorimetric sensor for cyanide with a sensing mechanism via nucleophilic addition of cyanide anion to the benzothiolium group. Cou-BT shows high sensitivity and selectivity for cyanide detection over other common anion species in aqueous acetonitrile solution. The calculated pseudo-first-order rate constant for cyanide anion addition was (2.13 ± 0.08) × 10(-2) s(-1) at 298 K, and the detection limit was estimated to be 0.64 µM. The DFT and TDDFT calculation results suggest that the ratiometric and colorimetric sensing behavior of Cou-BT upon its reaction with cyanide was due to the interrupted π-conjugation and blocked ICT progress.


Assuntos
Colorimetria/métodos , Corantes/química , Cumarínicos/química , Cianetos/análise , Ânions/análise , Modelos Moleculares , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos , Espectrofotometria/métodos
16.
Chem Commun (Camb) ; 48(42): 5094-6, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22514021

RESUMO

A novel sensitive and specific Hg(2+) chemodosimeter, derived from 1',3'-dithiane-substituted 2,1,3-benzoxadiazole, displays "turn-on" fluorescent and colorimetric responses via an Hg(2+)-triggered aldehyde recovery reaction. Its potential to monitor Hg(2+) in living organisms has been demonstrated using zebrafish larvae.


Assuntos
Compostos Heterocíclicos/química , Mercúrio/química , Aldeídos/química , Animais , Benzoxazóis/química , Colorimetria , Corantes Fluorescentes/química , Íons/química , Larva/metabolismo , Peixe-Zebra/crescimento & desenvolvimento
17.
J Org Chem ; 76(24): 10286-90, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22088170

RESUMO

A dicyanovinyl-substituted benzofurazan derivative (C1) was prepared as an efficient ratiometric chemosensor for cyanide anion detection in aqueous acetonitrile solution. Mechanism studies suggested that the nucleophilic addition of cyanide to the α-position of the dicyanovinyl group blocked the ICT progress of C1 and induced remarkable emission and absorption shift.


Assuntos
Benzoxazóis/síntese química , Cianetos/análise , Corantes Fluorescentes/síntese química , Compostos de Vinila/síntese química , Acetonitrilas/química , Ânions/análise , Técnicas de Química Analítica , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Sensibilidade e Especificidade , Soluções , Espectrometria de Fluorescência , Água
18.
Dalton Trans ; 40(10): 2173-6, 2011 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21088789

RESUMO

Terpyridine/benzofurazan conjugation results in a new hybrid fluorophore of the colorimetric sensing ability for Fe(2+) and fluorimetric sensing ability for XII group cations. The improved emission properties and cell imaging ability imply it is a suitable platform to construct a fluorescent sensor for metal imaging in biological systems.


Assuntos
Benzoxazóis/química , Colorimetria/métodos , Corantes Fluorescentes/química , Metais/química , Piridinas/química , Benzotiadiazinas/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal , Óxidos/química , Teoria Quântica
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