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1.
Acc Chem Res ; 56(10): 1239-1250, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37094181

RESUMO

ConspectusRedox flow batteries (RFBs) represent a promising modality for electrical energy storage. In these systems, energy is stored via paired redox reactions of molecules on opposite sides of an electrochemical cell. Thus, a central objective for the field is to design molecules with the optimal combination of properties to serve as energy storage materials in RFBs. The ideal molecules should undergo reversible redox reactions at relatively high potentials (for the molecule that is oxidized during battery charging, called the catholyte) or low potentials (for the species that is reduced during battery charging, called the anolyte). Furthermore, anolytes and catholytes must be highly soluble in the electrolyte solution and stable to extended electrochemical cycling in all battery-relevant redox states. The ideal candidates would undergo more than one reversible electron transfer event. Finally, the optimal structures should be resistant to crossover through a selective separator in order to maintain isolation of the two sides of the cell. This Account describes our design and optimization of organic molecules for this application. We first provide background for the metrics and experiments used to characterize anolytes/catholytes and to progress them toward deployment in flow batteries. We then use our studies of aminocyclopropenium-based catholytes to illustrate this workflow and approach.We identified tris(dimethylamino) cyclopropenium hexafluorophosphate as a first-generation catholyte for nonaqueous RFBs based on literature reports from the 1970s describing its reversible chemical and electrochemical oxidation. Cyclic voltammetry and electrochemical cycling experiments in acetonitrile/LiPF6 confirmed that this molecule undergoes oxidation at relatively high potential (0.86 V versus ferrocene/ferrocenium) and exhibits moderate stability toward charge-discharge cycling. Replacing the methyl groups with isopropyl substituents led to enhanced cycling stability but poor solubility of the radical dication (<0.1 M in acetonitrile). Solubility was optimized using quantitative structure-property relationship modeling, which predicted derivatives with ≥10-fold enhanced solubility. Cyclopropeniums with 300-500 mV higher redox potentials were identified by replacing one of the dialkylamino substituents with a less electron-donating thioalkyl or aryl group. Multielectron catholytes were developed by creating hybrid structures that contain a di(amino) cyclopropenium conjugated with a phenothiazine moeity. Finally, oligomeric tris(amino) cyclopropeniums were designed as crossover resistant catholytes. Optimization of their solubility enabled the deployment of these oligomers in high concentration asymmetric redox flow batteries with energy densities that are comparable to the state-of-the-art commercial aqueous inorganic systems.

2.
Small ; 19(38): e2301433, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37263991

RESUMO

Lithium metal batteries are intensively studied due to the potential to bring up breakthroughs in high energy density devices. However, the inevitable growth of dendrites will cause the rapid failure of battery especially under high current density. Herein, the utilization of tetrachloroethylene (C2 Cl4 ) is reported as the electrolyte additive to induce the formation of the LiCl-rich solid electrolyte interphase (SEI). Because of the lower Li ion diffusion barrier of LiCl, such SEI layer can supply sufficient pathway for rapid Li ion transport, alleviate the concentration polarization at the interface and inhibit the growth of Li dendrites. Meanwhile, the C2 Cl4 can be continuously replenished during the cycle to ensure the stability of the SEI layer. With the aid of C2 Cl4 -based electrolyte, the Li metal electrodes can maintain stable for >300 h under high current density of 50 mA cm-2 with areal capacity of 5 mAh cm-2 , broadening the compatibility of lithium metal anode toward practical application scenarios.

3.
Small ; 18(14): e2106657, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35023632

RESUMO

Mapping technique has been the powerful tool for the design of next-generation energy storage devices. Unlike the traditional ion-insertion based lithium batteries, the Li-S battery is based on the complex conversion reactions, which require more cooperation from mapping techniques to elucidate the underlying mechanism. Therefore, in this review, the representative works of mapping techniques for Li-S batteries are summarized, and categorized into the studies of lithium metal anode and sulfur cathode, with sub-sections based on shared characterization mechanisms. Due to specific features of mapping techniques, various aspects such as compositional distribution, in-plain/cross section characterization, coin cell/pouch cell configuration, and structural/mechanical analysis are emphasized in each study, aiming for the guidance for developing strategies to improve the battery performances. Benefited from the achieved progresses, suggestions for future studies based on mapping techniques are proposed to accelerate the development and commercialization of the Li-S battery.

4.
Small ; 18(51): e2205470, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36328710

RESUMO

Lithium-sulfur (Li-S) batteries have attracted great interest due to their low cost, high theoretical energy density, and environmental friendliness. However, the sluggish conversion of lithium polysulfides (LiPS) to S and Li2 S during the charge/discharge process leads to unsatisfactory rate performance of lower to 0.1 C (1 C = 1675 mA g-1 ) especially for Li-S pouch batteries, thus hindering their practical applications in high power batteries. Here, well-defined and monodispersed Ni single-atom catalysts (SACs) embedded in highly porous nitrogen-doped graphitic carbons (NiSA-N-PGC) are designed and synthesized to form Ni-N4 catalytic sites at the atomic level. When serving as a bifunctional electrocatalyst, the Ni-N4 catalytic sites cannot only promote the interfacial conversion redox of LiPS by accelerating the transformation kinetics, but also suppress the undesirable shuttle effect by immobilizing LiPS. These findings are verified by both experimental results and DFT theoretical calculations. Furthermore, Li ions show low diffusion barrier on the surface of Ni-N4 sites, resulting in enhanced areal capacity of batteries. As a result, the Li-S battery delivers stable cycling life of more than 600 cycles with 0.069% capacity decay per cycle at a rate of 0.5 C. More importantly, the Li-S pouch cells with NiSA-N-PGC show an initial capacity of 1299 mAh g-1 at a rate of 0.2 C even with high sulfur loading of 6 mg cm-2 . This work opens up an avenue for developing single-atom catalysts to accelerate the kinetic conversion of LiPS for highly stable Li-S batteries.

5.
J Am Chem Soc ; 143(33): 13450-13459, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34387084

RESUMO

High redox potential, two-electron organic catholytes for nonaqueous redox flow batteries were developed by appending diaminocyclopropenium (DAC) substituents to phenazine and phenothiazine cores. The parent heterocycles exhibit two partially reversible oxidations at moderate potentials [both at lower than 0.7 V vs ferrocene/ferrocenium (Fc/Fc+)]. The incorporation of DAC substituents has a dual effect on these systems. The DAC groups increase the redox potential of both couples by ∼300 mV while simultaneously rendering the second oxidation (which occurs at 1.20 V vs Fc/Fc+ in the phenothiazine derivative) reversible. The electron-withdrawing nature of the DAC unit is responsible for the increase in redox potential, while the DAC substituents stabilize oxidized forms of the molecules through resonance delocalization of charge and unpaired spin density. These new catholytes were deployed in two-electron redox flow batteries that exhibit voltages of up to 2.0 V and no detectable crossover over 250 cycles.

6.
Biomed Eng Online ; 20(1): 35, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823856

RESUMO

BACKGROUND: Aging is the major risk factor for most human cancers. We aim to develop and validate a reliable aging-related gene pair signature (ARGPs) to predict the prognosis of gastric cancer (GC) patients. METHODS: The mRNA expression data and clinical information were obtained from two public databases, The Cancer Genome Atlas (TCGA) dataset, and Gene Expression Omnibus (GEO) dataset, respectively. The best prognostic signature was established using Cox regression analysis (univariate and least absolute shrinkage and selection operator). The optimal cut-off value to distinguish between high- and low-risk patients was found by time-dependent receiver operating characteristic (ROC). The prognostic ability of the ARGPS was evaluated by a log-rank test and a Cox proportional hazards regression model. RESULTS: The 24 ARGPs were constructed for GC prognosis. Using the optimal cut-off value - 0.270, all patients were stratified into high risk and low risk. In both TCGA and GEO cohorts, the results of Kaplan-Meier analysis showed that the high-risk group has a poor prognosis (P < 0.001, P = 0.002, respectively). Then, we conducted a subgroup analysis of age, gender, grade and stage, and reached the same conclusion. After adjusting for a variety of clinical and pathological factors, the results of multivariate COX regression analysis showed that the ARGPs is still an independent prognostic factor of OS (HR, 4.919; 95% CI 3.345-7.235; P < 0.001). In comparing with previous signature, the novel signature was superior, with an area under the receiver operating characteristic curve (AUC) value of 0.845 vs. 0.684 vs. 0.695. The results of immune infiltration analysis showed that the abundance of T cells follicular helper was significantly higher in the low-risk group, while the abundance of monocytes was the opposite. Finally, we identified and incorporated independent prognostic factors and developed a superior nomogram to predict the prognosis of GC patients. CONCLUSION: Our study has developed a robust prognostic signature that can accurately predict the prognostic outcome of GC patients.


Assuntos
Envelhecimento/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Humanos , Estimativa de Kaplan-Meier , Prognóstico
7.
Angew Chem Int Ed Engl ; 60(52): 27039-27045, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34672070

RESUMO

This report describes the design of diaminocyclopropenium-phenothiazine hybrid catholytes for non-aqueous redox flow batteries. The molecules are synthesized in a rapid and modular fashion by appending a diaminocyclopropenium (DAC) substituent to the nitrogen of the phenothiazine. Combining a versatile C-N coupling protocol (which provides access to diverse derivatives) with computation and structure-property analysis enabled the identification of a catholyte that displays stable two-electron cycling at potentials of 0.64 and 1.00 V vs. Fc/Fc+ as well as high solubility in all oxidation states (≥0.45 M in TBAPF6 /MeCN). This catholyte was deployed in a high energy density two-electron RFB, exhibiting >90 % capacity retention over 266 hours of flow cell cycling at >0.5 M electron concentration.

8.
J Am Chem Soc ; 142(41): 17564-17571, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33006474

RESUMO

This Article describes the development of 1,2-bis(diisopropylamino)-3-cyclopropenylium-functionalized (DAC-functionalized) benzene derivatives as high-potential catholytes for non-aqueous redox flow batteries. Density functional theory (DFT) calculations predict that the oxidation potentials (in CH3CN) of various DAC-benzene derivatives will range from +0.96 to +1.64 V vs Fc+/0, depending upon the substituents on the benzene ring. To test these predictions, a set of eight DAC-arene derivatives were synthesized and evaluated electrochemically. The molecule 1-DAC-4-tert-butyl-2-methoxy-5-pentafluoropropoxybenzene was found to offer the optimal balance of high redox potential (E1/2 = +1.19 V vs Fc+/0) and charge-discharge cycling stability (with 92% capacity retention over 116 h of cycling at 0.3 M concentration in a symmetrical flow cell). This optimal derivative was successfully deployed as a catholyte in a non-aqueous redox flow cell with butyl viologen as the anolyte to yield a 2.0 V battery.

9.
J Am Chem Soc ; 141(38): 15301-15306, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31503480

RESUMO

Nonaqueous redox flow batteries (RFBs) represent a promising technology for grid-scale energy storage. A key challenge for the field is identifying molecules that undergo reversible redox reactions at the extreme potentials required to leverage the large potential window of organic solvents. In this Article, we use a combination of computations, chemical synthesis, and mechanistic analysis to develop thioether-substituted cyclopropenium derivatives as high potential electrolytes for nonaqueous RFBs. These molecules exhibit redox potentials that are 470-500 mV higher than those of known electrolytes. Strategic variation of the alkyl substituent on sulfur afforded a derivative that undergoes charge-discharge cycling at +1.33 V vs ferrocene/ferrocenium in acetonitrile/tetrabutylammonium hexafluorophosphate. This electrolyte was paired with a phthalimide derivative to achieve a proof-of-principle 3.2 V all-organic RFB.

10.
J Am Chem Soc ; 141(26): 10171-10176, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31203608

RESUMO

The implementation of redox active organics in nonaqueous redox flow batteries requires the design of molecules that exhibit high solubility (>1 M) in all battery-relevant redox states. Methods for forecasting nonaqueous solubility would be valuable for streamlining the identification of promising structures. Herein we report the development of a workflow to parametrize and predict the solubility of conformationally flexible tris(dialkylamino)cyclopropenium (CP) radical dications. A statistical model is developed through training on monomer species. Ultimately, this model is used to predict new monomeric and dimeric CP derivatives with solubilities of >1 M in acetonitrile in all oxidation states. The most soluble CP monomer exhibits high stability to electrochemical cycling at 1 M in acetonitrile without a supporting electrolyte in a symmetrical flow cell.


Assuntos
Ciclopropanos/química , Fontes de Energia Elétrica , Eletrólitos/química , Modelos Moleculares , Estrutura Molecular , Oxirredução , Solubilidade
11.
Angew Chem Int Ed Engl ; 58(14): 4484-4502, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30277009

RESUMO

Electrocatalytic water splitting is one of the most promising sustainable energy conversion technologies, but is limited by the sluggish electrochemical reactions. Inorganic nanomaterials have been widely used as efficient catalysts for promoting the electrochemical kinetics. Several approaches to optimize the activities of these nanocatalysts have been developed. The electronic structures of the catalysts play a pivotal role in governing the activity and thus have been identified as an essential descriptor. However, the underlying working mechanisms related to the refined electronic structures remain elusive. To establish the structure-electronic-behavior-activity relationship, a comprehensive overview of the developed strategies to regulate the electronic structures is presented, emphasizing the surface modification, strain, phase transition, and heterostructure. Current challenges to the fundamental understanding of electron behaviors in the nanocatalysts are fully discussed.

12.
Chin J Cancer Res ; 31(3): 499-510, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31354219

RESUMO

OBJECTIVE: Currently, no satisfactory targets for colorectal cancer or markers for immunotherapy and diagnosis and prognosis are available. Immunoglobulin G (IgG) is widely expressed in many cancers, and it promotes cancer progression. This study explored the role of cancer-derived IgG (CIgG) in colorectal cancer. METHODS: First, using a monoclonal antibody to CIgG, we examined the expression levels of CIgG in colorectal cancer cell lines by western blot and immunofluorescence analyses and in tissue specimens by immunohistochemistry. Second, the variable region gene was amplified by nested polymerase chain reaction (PCR), and PCR products were sequenced and analyzed. Third, we investigated the effect of CIgG on colorectal cancer cells by cell proliferation, wound healing, migration and invasion assays, and colony formation assay. Fourth, we performed in vivo tumorigenicity experiments to explore the effect of CIgG on tumorigenicity. Finally, we used RNA-seq analysis and co-immunoprecipitation experiments to further clarify possible mechanisms of CIgG. RESULTS: We found that CIgG is widely expressed in colorectal cancer cells, and the overexpression of CIgG indicates significantly poor colorectal cancer prognosis. Furthermore, CIgG knockdown significantly inhibits the proliferation, migration and invasion ability of cells, and tumor growth in vivo. RNA-seq analysis indicated that CIgG knockdown results primarily in changes in expression of apical junction and epithelial-mesenchymal transition-related genes. CIgG may be involved in colorectal cancer invasion and metastasis through interacting with E-cadherin. CONCLUSIONS: CIgG is a potential human oncogene in colorectal cancer and that it has potential for application as a novel target in targeted therapy and a marker for prognostic evaluation.

13.
Small ; 14(38): e1802477, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30146774

RESUMO

Cu nanocrystals of various shapes are synthesized via a universal, eco-friendly, and facile colloidal method on Al substrates using hexadecylamine (HDA) as a capping agent and glucose as a reductant. By tuning the concentration of the capping agent, hierarchical 3D Cu nanocrystals show pronounced surface-enhanced Raman scattering (SERS) through the concentrated hot spots at the sharp tips and gaps due to the unique 3D structure and the resulting plasmonic couplings. Intriguingly, 3D sword-shaped Cu crystals have the highest enhancement factor (EF) because of their relatively uniform size distribution and alignment. This work opens new pathways for efficiently realizing morphology control for Cu nanocrystals as highly efficient SERS platforms.

14.
Tumour Biol ; 37(6): 7267-76, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26666821

RESUMO

Vasohibin-1 is an intrinsic inhibitor of angiogenesis induced by VEGF-A. However, there little is known about the relationship between Vasohibin-1 expression, angiogenesis, and tumor-associated macrophages (TAMs). Vasohibin-1 expression, VEGF-A expression, microvessel density (MVD) marked with CD34, and density of cells marked with CD68 were measured in 111 paraffin-embedded tissues of gastric cancer by immunohistochemistry. The length of tube forming structures of endothelial cells and mobility rate of gastric cancer cells in Matrigel were tested by three-dimensional live cell imaging system. The effect of TAMs on the tumor growth, MVD, and Vasohibin-1 expression was measured by nude mice tumor genesis assay in vivo. We found that high Vasohibin-1 protein expression correlated significantly with worse TNM stage (P = 0.002), metastatic lymph node (P = 0.014), distant metastasis (P = 0.022), overall survival (P < 0.001), and progression-free survival (P < 0.001) compared to those with low Vasohibin-1 expression. Vasohibin-1 protein expression had statistical correlation with the MVD (r = 0.860, P < 0.001), density of CD68(+) cells (r = 0.882, P < 0.001), and VEGF-A expression (r = 0.719, P < 0.001) in the gastric cancer tissues. Decreasing Vasohibin-1 expression with siRNA increased the length of tube forming structures of endothelial cells in co-culture with endothelial cells (EA-hy923), macrophages, and gastric cancers (Hs746T). Tumor volume (P = 0.001), Vasohibin-1 (P < 0.001), and VEGF-A (P < 0.001) expression in mice inoculated with AGS and THP (10:1) was significantly higher than that with AGS alone (P = 0.001). Vasohibin-1 protein expression had statistical correlation with VEGF expression (r = 0.786, P < 0.001) and MVD (r = 0.496, P = 0.014) in gastric xenografted tumor. Therefore, Vasohibin-1 might be a potential marker of worse prognosis and therapeutic target in gastric cancer. Vasohibin-1 might play an important role in the process of angiogenesis regulated by TAMs.


Assuntos
Carcinoma/genética , Proteínas de Ciclo Celular/fisiologia , Macrófagos/fisiologia , Proteínas de Neoplasias/fisiologia , Neovascularização Patológica/fisiopatologia , Neoplasias Gástricas/genética , Idoso , Animais , Carcinoma/irrigação sanguínea , Carcinoma/patologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Intervalo Livre de Doença , Feminino , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microvasos/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Interferência de RNA , RNA Interferente Pequeno/genética , Distribuição Aleatória , Método Simples-Cego , Organismos Livres de Patógenos Específicos , Neoplasias Gástricas/irrigação sanguínea , Neoplasias Gástricas/patologia , Fator A de Crescimento do Endotélio Vascular/análise
15.
BMC Cancer ; 15: 437, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-26016795

RESUMO

BACKGROUND: Recent studies have indicated the possible function of miR-217 in tumorigenesis. However, the roles of miR-217 in colorectal cancer (CRC) are still largely unknown. METHODS: We examined the expression of miR-217 and AEG-1 in 50 CRC tissues and the corresponding noncancerous tissues by qRT-PCR. The clinical significance of miR-217 was analyzed. CRC cell lines with miR-217 upregulation and AEG-1 silencing were established and the effects on tumor growth in vitro and in vivo were assessed. Dual-luciferase reporter gene assays were also performed to investigate the interaction between miR-217 and AEG-1. RESULTS: Our data demonstrated that miR-217 was significantly downregulated in 50 pairs of colorectal cancer tissues. MiR-217 expression levels were closely correlated with tumor differentiation. Moreover, decreased miR-217 expression was also associated with shorter overall survival of CRC patients. MiR-217 overexpression significantly inhibited proliferation, colony formation and invasiveness of CRC cells by promoting apoptosis and G0/G1 phase arrest. Interestingly, ectopic miR-217 expression decreased AEG-1 expression and repressed luciferase reporter activity associated with the AEG-1 3'-untranslated region (UTR). AEG-1 silencing resulted in similar biological behavior changes to those associated with miR-217 overexpression. Finally, in a nude mouse xenografted tumor model, miR-217 overexpression significantly suppressed CRC cell growth. CONCLUSIONS: Our findings suggest that miR-217 has considerable value as a prognostic marker and potential therapeutic target in CRC.


Assuntos
Biomarcadores Tumorais/biossíntese , Moléculas de Adesão Celular/biossíntese , Neoplasias Colorretais/genética , MicroRNAs/biossíntese , Idoso , Animais , Apoptose/genética , Biomarcadores Tumorais/genética , Moléculas de Adesão Celular/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana , Camundongos , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Proteínas de Ligação a RNA , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Gastroenterol Hepatol ; 30(9): 1367-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25866896

RESUMO

BACKGROUND AND AIM: Increasing evidence has indicated that long noncoding ribonucleic acids (lncRNAs) play a major role in cancers. Although certain lncRNAs has been reported to play a role in gastric cancer (GC), specific lncRNAs involved in distant metastasis of GC remain unknown. METHODS: Differentially expressed mRNAs and lncRNAs between stage IV and non-stage IV GC were obtained by microarray. Gene ontology and pathway analysis were used to study functions of differential mRNAs. Algorithms were used to predict potential gene targets of cis or trans-acting lncRNAs. Network analysis was performed to analyze each pair of gene-lncRNA, gene-gene, or lncRNA-lncRNA interactions. Expression of lncRNA special for distant metastasis of GC (SDMGC) and target gene TRIM16 were tested in GC tissues and cell lines. RNAi and overexpression were used to observe the biological functions of SDMGC and TRIM16 on GC cells. RESULTS: 502 mRNAs and 440 lncRNAs were found to be differentially expressed. 74 gene ontology terms and 38 pathways were associated with the dysregulated transcripts. Fourteen core factors were determined by network analysis. Expression of SDMGC and TRIM16 was upregulated in the distant metastasis tissues, compared with primary GC tissues, which were positive correlation. Silencing of SDMGC or TRIM16 was demonstrated to decrease cell invasion and migration, while upregulated of SDMGC or TRIM16 could promote cell invasion and migration. However, little effect on proliferation, cell cycle, colony formation, and apoptosis was found. CONCLUSIONS: SDMGC is obviously upregulated in stage IV GC and may represent a new marker and therapeutic target for GC treatment.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Expressão Gênica/genética , Metástase Neoplásica/genética , RNA Longo não Codificante/fisiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Fatores de Transcrição/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Humanos , Invasividade Neoplásica/genética , Estadiamento de Neoplasias , Interferência de RNA , RNA Mensageiro/genética , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Regulação para Cima
17.
Oncol Lett ; 27(2): 80, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38249814

RESUMO

Rectal cancer is one of the most malignant tumors, and postoperative recurrence and metastasis are the main reasons for treatment failure. Lymph node metastasis is the main metastatic pathway of rectal cancer. The present study aimed to investigate the role of lateral lymph node dissection (LLND) in patients with rectal cancer using a meta-analysis. Articles in Chinese and English related to the application of LLND in patients with rectal cancer were retrieved and eligible studies were selected for data analysis. Evaluation indicators included the 5-year survival rate, recurrence rate, urinary system function and operation time. The random-effects model was utilized for the analysis. A total of 10 studies that met the eligibility criteria were selected, comprising 2,272 patients, including 1,101 cases in the LLND group and 1,171 cases in the non-LLND group. No significant difference was found between the two groups in terms of local recurrence rate, 5-year disease-free survival (DFS) rate, and DFS rate at the follow-up. It is noteworthy that cases in the LLND group had no significantly longer overall survival, but had a higher 5-year survival rate. However, cases in the LLND group had a longer operation time and worse urinary dysfunction. The results remained consistent throughout separate analyses for different research quality sources. The present meta-analysis showed that LLND provided a specific advantage in prolonging survival time. However, it was associated with prolonged operation time and an increased incidence of urinary dysfunction.

18.
IEEE Trans Pattern Anal Mach Intell ; 46(8): 5852-5872, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38376963

RESUMO

Video compression is indispensable to most video analysis systems. Despite saving the transportation bandwidth, it also deteriorates downstream video understanding tasks, especially at low-bitrate settings. To systematically investigate this problem, we first thoroughly review the previous methods, revealing that three principles, i.e., task-decoupled, label-free, and data-emerged semantic prior, are critical to a machine-friendly coding framework but are not fully satisfied so far. In this paper, we propose a traditional-neural mixed coding framework that simultaneously fulfills all these principles, by taking advantage of both traditional codecs and neural networks (NNs). On one hand, the traditional codecs can efficiently encode the pixel signal of videos but may distort the semantic information. On the other hand, highly non-linear NNs are proficient in condensing video semantics into a compact representation. The framework is optimized by ensuring that a transportation-efficient semantic representation of the video is preserved w.r.t. the coding procedure, which is spontaneously learned from unlabeled data in a self-supervised manner. The videos collaboratively decoded from two streams (codec and NN) are of rich semantics, as well as visually photo-realistic, empirically boosting several mainstream downstream video analysis task performances without any post-adaptation procedure. Furthermore, by introducing the attention mechanism and adaptive modeling scheme, the video semantic modeling ability of our approach is further enhanced. Fianlly, we build a low-bitrate video understanding benchmark with three downstream tasks on eight datasets, demonstrating the notable superiority of our approach. All codes, data, and models will be open-sourced for facilitating future research.

19.
J Fungi (Basel) ; 10(2)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38392830

RESUMO

Natural rubber is an important national strategic and industrial raw material. The leaf anthracnose of rubber trees caused by the Colletotrichum species is one of the important factors restricting the yields of natural rubber. In this study, we isolated and identified strain Bacillus velezensis SF334, which exhibited significant antagonistic activity against both C. australisinense and C. siamense, the dominant species of Colletotrichum causing rubber tree leaf anthracnose in the Hainan province of China, from a pool of 223 bacterial strains. The cell suspensions of SF334 had a significant prevention effect for the leaf anthracnose of rubber trees, with an efficacy of 79.67% against C. siamense and 71.8% against C. australisinense. We demonstrated that SF334 can lead to the lysis of C. australisinense and C. siamense mycelia by causing mycelial expansion, resulting in mycelial rupture and subsequent death. B. velezensis SF334 also harbors some plant probiotic traits, such as secreting siderophore, protease, cellulase, pectinase, and the auxin of indole-3-acetic acid (IAA), and it has broad-spectrum antifungal activity against some important plant pathogenic fungi. The genome combined with comparative genomic analyses indicated that SF334 possesses most genes of the central metabolic and gene clusters of secondary metabolites in B. velezensis strains. To our knowledge, this is the first time a Bacillus velezensis strain has been reported as a promising biocontrol agent against the leaf anthracnose of rubber trees caused by C. siamense and C. australisinense. The results suggest that B. velezensis could be a potential candidate agent for the leaf anthracnose of rubber trees.

20.
Adv Mater ; 36(21): e2312880, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330999

RESUMO

While layered metal oxides remain the dominant cathode materials for the state-of-the-art lithium-ion batteries, conversion-type cathodes such as sulfur present unique opportunities in developing cheaper, safer, and more energy-dense next-generation battery technologies. There has been remarkable progress in advancing the laboratory scale lithium-sulfur (Li-S) coin cells to a high level of performance. However, the relevant strategies cannot be readily translated to practical cell formats such as pouch cells and even battery pack. Here these key technical challenges are addressed by molecular engineering of the Li metal for hydrophobicization, fluorination and thus favorable anode chemistry. The introduced tris(2,4-di-tert-butylphenyl) phosphite (TBP) and tetrabutylammonium fluoride (TBA+F-) as well as cellulose membrane by rolling enables the formation of a functional thin layer that eliminates the vulnerability of Li metal towards the already demanding environment required (1.55% relative humidity) for cell production and gives rise to LiF-rich solid electrolyte interphase (SEI) to suppress dendrite growth. As a result, Li-S pouch cells assembled at a pilot production line survive 400 full charge/discharge cycles with an average Coulombic efficiency of 99.55% and impressive rate performance of 1.5 C. A cell-level energy density of 417 Wh kg-1 and power density of 2766 W kg-1 are also delivered via multilayer Li-S pouch cell. The Li-S battery pack can even power an unmanned aerial vehicle of 3 kg for a fairly long flight time. This work represents a big step forward acceleration in Li-S battery marketization for future energy storage featuring improved safety, sustainability, higher energy density as well as reduced cost.

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