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1.
Cancer Sci ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890815

RESUMO

Common epidermal growth factor receptor (EGFR) mutations are usually not considered for immunotherapy in non-small cell lung cancer (NSCLC) due to poor efficacy. However, whether uncommon EGFR mutations are suitable for immunotherapy has not been thoroughly studied. Thus, we explored the tumor immune microenvironment (TME) features in uncommon EGFR mutant NSCLC. In this study, a total of 41 patients with EGFR mutations were included, the majority (85.4%) of whom were stage I. Among them, 22 patients harbored common mutations, while 19 patients presented with uncommon mutations. Compared with common mutations, uncommon mutations exhibited more infiltrating T cells and fewer M2 macrophages, upregulated expression of antigen processing and a presentation pathway. Unsupervised clustering based on the mIF profile identified two classes with heterogeneous TME in uncommon mutations. Class 1 featured the absence of PD-1+ cytotoxic T cell infiltration, and class 2 displayed a hotter TME because of the downregulated expression of hypoxia (p < 0.001), oxidative phosphorylation (p = 0.009), and transforming growth factor beta signaling (p = 0.01) pathways as well as increased expression of CTLA4 (p = 0.001) and PDCD1 (p = 0.004). The association of CTLA4 and PDCD1 with TME profiles was validated in a TCGA lung adenocarcinoma cohort with uncommon EGFR mutations. Our study reveals the distinct and heterogeneous TME features in uncommon EGFR mutant NSCLC.

2.
Cancer Epidemiol ; 91: 102585, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38815483

RESUMO

BACKGROUND: Trachea, bronchus, and lung (TBL) cancer has demonstrated a discernible feminization and a tendency towards younger onset in recent decades. Therefore, our objective is to examine the most recent patterns in the worldwide prevalence of TBL among women of reproductive age on a global, regional, and national scale. METHODS: To assess the prevalence trends of TBL in women of reproductive age, we calculated the estimated annual percentage change (EAPC), age-standardized incidence rate (ASIR), age-standardized death rate (ASDR), and disability-adjusted life years (DALYs) for 204 countries and territories from 1990 to 2019. These calculations were based on the Global Burden of Disease (GBD) 2019 database. RESULTS: From 1990 to 2019, there was a global increase in the absolute number of incidence cases, deaths, and DALYs of TBL in women of reproductive age. However, the ASIR, ASDR, and age-standardized DALY rates were decreasing over this period, with EAPC of -0.77 (95 % confidence interval [CI]: -1.03 to -0.51), -1.08 (95 % CI: -1.34 to -0.82), and -1.10 (95 % CI: -1.36 to -0.84), respectively. This trend was observed even in regions with higher Socio-Demographic Index (SDI). East Asia consistently had the highest ASIR, ASDR, and age-standardized DALY rate, but there was a decreasing trend. Conversely, Eastern Sub-Saharan Africa displayed an increasing burden pattern. When examining countries individually, Monaco, Greenland, and Palau had the highest ASIR. Moreover, in most countries, the ASIR for TBL increased with age, particularly among women aged 35-49 years. CONCLUSIONS: Despite a global decline in ASIR, ASDR, and age-standardized DALY rates for TBL in women of reproductive age over the past three decades, there is still a troubling increase observed in low- and low-middle SDI regions. It is crucial to implement effective preventive and curative measures in these regions in order to address this concerning trend.

3.
Inorg Chem ; 63(21): 9706-9710, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38747511

RESUMO

Herein, we detail the synthesis, structure, and photoconductivity of the uranyl dithiophosphinate single crystal UO2[S2P(C6H5)2]2(CH3OH)·CH3OH (denoted as U-DPDPP). The formation of bonds between uranyl ions and sulfur-based ligands endows U-DPDPP with a distinct electronic absorption property with a broadband spectrum spanning from 250 to 550 nm, giving rise to a unique semiconductive property. Under X-ray illumination, U-DPDPP displays a distinctive photoconductivity response, with a charge carrier mobility lifetime (µτ) of 2.78 × 10-4 cm2·V-1 achieved, which contradicts the electronic-silence behavior of uranyl nitrate crystal.

4.
5.
Medicine (Baltimore) ; 103(16): e37879, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640268

RESUMO

In response to the high incidence and poor prognosis of lung cancer, this study tends to develop a generalizable lung-cancer prediction model by using machine learning to define high-risk groups and realize the early identification and prevention of lung cancer. We included 467,888 participants from UK Biobank, using lung cancer incidence as an outcome variable, including 49 previously known high-risk factors and less studied or unstudied predictors. We developed multivariate prediction models using multiple machine learning models, namely logistic regression, naïve Bayes, random forest, and extreme gradient boosting models. The performance of the models was evaluated by calculating the areas under their receiver operating characteristic curves, Brier loss, log loss, precision, recall, and F1 scores. The Shapley additive explanations interpreter was used to visualize the models. Three were ultimately 4299 cases of lung cancer that were diagnosed in our sample. The model containing all the predictors had good predictive power, and the extreme gradient boosting model had the best performance with an area under curve of 0.998. New important predictive factors for lung cancer were also identified, namely hip circumference, waist circumference, number of cigarettes previously smoked daily, neuroticism score, age, and forced expiratory volume in 1 second. The predictive model established by incorporating novel predictive factors can be of value in the early identification of lung cancer. It may be helpful in stratifying individuals and selecting those at higher risk for inclusion in screening programs.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Biobanco do Reino Unido , Teorema de Bayes , Bancos de Espécimes Biológicos , Aprendizado de Máquina , Fatores de Risco
6.
Inorg Chem ; 63(8): 3642-3647, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38346447

RESUMO

Two X-ray scintillators based on organic-inorganic hybrids were constructed by judiciously incorporating lanthanide cations and organic ligands within a single material. The obtained Eu-pba and Tb-pba not only feature excellent radiation, hydrolytic, and thermal stabilities but also exhibit a linear response to the X-ray dose rate with detection limits of 4.92 and 3.17 µGy s-1, respectively. We further present a flexible scintillator film fabricated by embedding Tb-pba in a polydimethylsiloxane (PDMS) polymer. Their incorporation enables X-ray imaging with a spatial resolution of approximately 10 lp mm-1. These results emphasize the potential of lanthanide organic-inorganic hybrids to achieve outstanding performance in X-ray scintillation and imaging.

7.
ACS Cent Sci ; 9(9): 1827-1834, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37780354

RESUMO

Storage phosphors displaying defect emissions are indispensable in technologically advanced radiation dosimeters. The current dosimeter is limited to the passive detection mode, where ionizing radiation-induced deep-trap defects must be activated by external stimulation such as light or heat. Herein, we designed a new type of shallow-trap storage phosphor by controlling the dopant amounts of Ag+ and Bi3+ in the host lattice of Cs2NaInCl6. A distinct phenomenon of X-ray-induced emission (XIE) is observed for the first time in an intrinsically nonemissive perovskite. The intensity of XIE exhibits a quantitative relationship with the accumulated dose, enabling a real-time radiation dosimeter. Thermoluminescence and in situ X-ray photoelectron spectroscopy verify that the emission originates from the radiative recombination of electrons and holes associated with X-ray-induced traps. Theoretical calculations reveal the evolution process of Cl-Cl dimers serving as hole trap states. Analysis of temperature-dependent radioluminescence spectra provides evidence that the intrinsic electron-phonon interaction in 0.005 Ag+@ Cs2NaInCl6 is significantly reduced under X-ray irradiation. Moreover, 0.025 Bi3+@ Cs2NaInCl6 shows an elevated sensitivity to the accumulated dose with a broad response range from 0.08 to 45.05 Gy. This work discloses defect manipulation in halide double perovskites, giving rise to distinct shallow-trap storage phosphors that bridge traditional deep-trap storage phosphors and scintillators and enabling a brand-new type of material for real-time radiation dosimetry.

8.
J Am Chem Soc ; 145(24): 13161-13168, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37287236

RESUMO

Lanthanide organic frameworks (Ln-MOFs) have attracted increasing research enthusiasm as photoluminescent materials. However, limited luminescence efficiency stemming from restricted energy transfer efficiency from the organic linker to the metal center hinders their applications. Herein, a uranyl sensitization approach was proposed to boost the luminescence efficiency of Ln-MOFs in a distinct heterobimetallic uranyl-europium organic framework. The record-breaking photoluminescence quantum yield (PLQY, 92.68%) among all reported Eu-MOFs was determined to benefit from nearly 100% energy transfer efficiency between UO22+ and Eu3+. Time-dependent density functional theory and ab initio wave-function theory calculations confirmed the overlap of excited state levels between UO22+ and Eu3+, which is responsible for the efficient energy transfer process. Coupled with intrinsically strong stopping power toward X-ray of the uranium center, SCU-UEu-2 features an ultralow detection limit of 1.243 µGyair/s, outperforming the commercial scintillator LYSO (13.257 µGyair/s) and satisfying the requirement of X-ray diagnosis (below 5.5 µGyair/s) in full.

9.
Angew Chem Int Ed Engl ; 62(33): e202306465, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37249485

RESUMO

The development of high-performance X-ray detectors requires scintillators with fast decay time, high light yield, stability, and X-ray absorption capacity, which are difficult to achieve in a single material. Here, we present the first example of a lanthanide chalcogenide of LaCsSiS4 : 1 % Ce3+ that simultaneously integrates multiple desirable properties for an ideal scintillator. LaCsSiS4 : 1 % Ce3+ demonstrates a remarkably low detection limit of 43.13 nGyair s-1 and a high photoluminescence quantum yield of 98.24 %, resulting in a high light yield of 50480±1441 photons/MeV. Notably, LaCsSiS4 : 1 % Ce3+ exhibits a fast decay time of only 29.35±0.16 ns, making it one of the fastest scintillators among all lanthanide-based inorganic scintillators. Furthermore, this material shows robust radiation and moisture resistance, endowing it with suitability for chemical processing under solution conditions. To demonstrate the X-ray imaging capacity of LaCsSiS4 : 1 % Ce3+ , we fabricated a flexible X-ray detector that achieved a high spatial resolution of 8.2 lp mm-1 . This work highlights the potential of lanthanide chalcogenide as a promising candidate for high-performance scintillators.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36576783

RESUMO

Background: Circular RNAs (circ-RNAs) have been demonstrated to influence initiation, drug resistance, and metastasis of tumors. However, the effects of circular-phosphoglycerate mutase 1 (circ-PGAM1) on matrine resistance in nonsmall cell lung cancer (NSCLC) remain unknown. Materials and Methods: The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine gene expression. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and cell colony formation assays were used to evaluate NSCLC apoptosis and cell proliferation after indicated treatments, respectively. Results: circ-PGAM1 was upregulated in human NSCLC cell lines (H1299 and A549) compared with the human normal lung epithelial (BEAS-2B) cells. circ-PGAM1 overexpression reversed the matrine treatment-induced inhibition on proliferation of NSCLC cells (A549 and H1299) and rescued the matrine treatment-stimulated apoptosis of these cells. miR-326 was demonstrated to interact with circ-PGAM1. circ-PGAM1 knockdown enhanced the antitumor effect of matrine on NSCLC cell proliferation and apoptosis, which was reversed by miR-326 inhibition. The authors also identified CXCR5 as a key downstream target of miR-326 in A549 cells. Conclusions: circ-PGAM1 enhances matrine resistance of NSCLC cells through the miR-326/CXCR5 axis. The authors' findings provide new insights into NSCLC-targeted therapy.

11.
Front Genet ; 13: 1006936, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212146

RESUMO

Almost all cellular activities depend on protein folding, signaling complex assembly/disassembly, and epigenetic regulation. One of the most important regulatory mechanisms responsible for controlling these cellular processes is dynamic protein phosphorylation/dephosphorylation. Alterations in phosphorylation networks have major consequences in the form of disorders, including cancer. Many signaling cascades, including the target of rapamycin (TOR) signaling, are important participants in the cell cycle, and dysregulation in their phosphorylation/dephosphorylation status has been linked to malignancies. As a TOR signaling regulator, protein phosphatase 2A (PP2A) is responsible for most of the phosphatase activities inside the cells. On the other hand, TOR signaling pathway regulator (TIPRL) is an essential PP2A inhibitory protein. Many other physiological roles have also been suggested for TIPRL, such as modulation of TOR pathways, apoptosis, and cell proliferation. It is also reported that TIPRL was increased in various carcinomas, including non-small-cell lung carcinoma (NSCLC) and hepatocellular carcinomas (HCC). Considering the function of PP2A as a tumor suppressor and also the effect of the TIPRL/PP2A axis on apoptosis and proliferation of cancer cells, this review aims to provide a complete view of the role of TIPRL in cancer development in addition to describing TIPRL/PP2A axis and its epigenetic regulation.

12.
Healthcare (Basel) ; 10(10)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36292501

RESUMO

Peer relationships play an important role in the growth of children. This study offers insights about feelings of fear and inferiority in children's peer relationships. Based on a national survey, the 2018 Construction for Social Policy Support System for Urban and Rural Poor Families in China, initiated by the Ministry of Civil Affairs, and using multiple regression models and a structural equation model, this study discusses whether and how having a rural household registration or being from a poor (dibao) family has an isolation effect on fear and inferiority in children's peer relationships. The research findings indicate that children with a rural household registration or those from a dibao family are at a disadvantage in peer interactions. Moreover, rural resident identity has an indirect effect on children's fear of peers and inferiority, mainly through psychological resilience, anxiety and depression, and mobile phone dependence. Being from a dibao family directly influences children's fear and inferiority in their peer relationships; it also indirectly influences fear of peers and inferiority through psychological resilience. This study suggests that more attention should be paid to fear of peers and inferiority in rural children or children from a dibao family.

13.
Inorg Chem ; 61(34): 13256-13260, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-35969238

RESUMO

Hybrid metal halide perovskites are extensively synthesized using p- and d-elements. However, the properties of hybrid halide perovskites involving 5f-elements are still elusive. Herein, we first report the semiconductive property of a uranium-bearing hybrid halide perovskite, [N(C2H5)4]2UCl6 (EAUCl). Single crystal X-ray crystallography demonstrates that EAUCl adopts a zero-dimensional molecular structure consisting of isolated [UCl6]2- anions and organic cations. The intrinsically semiconductive property endows EAUCl with obvious charge transport and photoconductivity, with a high carrier mobility lifetime (µτ) product of 9.91 × 10-4 cm2/V and a photocurrent on-off ratio of 380 under X-ray excitation. Theoretical calculations corroborate that the U 5f orbitals are involved in electron transitions and the formation of band structure.

14.
Angew Chem Int Ed Engl ; 61(37): e202208440, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35859274

RESUMO

Scintillators display radioluminescent properties when irradiated by high-energy photons and therefore play an essential role in radiation detection. The current inventory of scintillators is overwhelmingly represented by achiral structures, where the radioluminescence propagates isotropically after generation. Herein, we demonstrate that chiral perovskites of (R-3AP)PbBr3 Cl⋅H2 O (R-3APP) and (S-3AP)PbBr3 Cl⋅H2 O (S-3APP) emerge as a new type of scintillator displaying a distinct property of circularly polarized radioluminescence (CPRL). A high quantum yield of 27.6 %, high luminescence dissymmetric factors (glum ) of 4×10-2 , and high X-ray absorption coefficients were observed for these compounds. As proof of concept, we fabricated a polarized scintillator pair by assembling chiral scintillator crystals, which provides a new strategy to attenuate optical crosstalk between the scintillators by precisely controlling the radioluminescence propagation and improves the X-ray imaging quality at the boundary region.

15.
Mol Diagn Ther ; 26(3): 309-322, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35305253

RESUMO

INTRODUCTION: Next-generation sequencing (NGS) enables simultaneous detection of actionable somatic variants and estimation of genomic signatures such as tumor mutational burden (TMB) or microsatellite instability (MSI) status, which empowers therapeutic decisions in clinical oncology. OBJECTIVE: Our retrospective study investigated the clinical performance of somatic variant detection in paired tissue and blood samples using a large targeted gene panel, the OncoScreen Plus, which interrogates 520 cancer-related genes. METHODS: We analyzed sequencing data derived from paired tissue and blood samples of 3005 patients spanning 20 solid tumor types, including lung (n = 1971), gastrointestinal (n = 625), breast (n = 120) and gynecological (n = 110), genitourinary (n = 38), and other cancers (n = 141). RESULTS: Across tumor types, the OncoScreen Plus panel achieved a high tissue detection rate, with an average of 97.9%. The average plasma detection rate was 72.2%, with an average tissue concordance rate of 36.6%. Considering all variant types, the plasma assay yielded an average sensitivity/true positive rate of 45.7%, with a positive predictive value of 64.7% relative to tissue assay. Pearson correlation analysis revealed a strong correlation in TMB estimated from blood and tissue samples (correlation coefficient 0.845, R2 = 0.756). MSI-high status was identified in five tumor types, including endometrial cancer (28.6%), colorectal cancer (2.5%), ovarian cancer (2.0%), gastric cancer (1.5%), and lung adenocarcinoma (0.2%). CONCLUSION: Paired tumor and blood samples from a large cohort of patients spanning 20 tumor types demonstrated that the OncoScreen Plus is a reliable pan-cancer panel for the accurate detection of somatic variants and genomic signatures that could guide individualized treatment strategies to improve the care of patients with advanced cancer.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias , Biomarcadores Tumorais/genética , Genômica , Humanos , Instabilidade de Microssatélites , Mutação , Neoplasias/diagnóstico , Neoplasias/genética , Estudos Retrospectivos
16.
Ann Palliat Med ; 10(4): 4999-5009, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33966436

RESUMO

Lung cancer is a malignancy with the highest morbidity and mortality in the world. Radiotherapy, chemotherapy, targeted therapy, and immunotherapy have been widely used to treat metastatic non-small cell lung cancer (NSCLC). Stereotactic body radiotherapy (SBRT), also known as stereotactic ablation radiotherapy (SABR), can precisely deliver a high dose of radiation to a target in a limited area. SBRT has been established as the standard treatment for patients with early NSCLC who are unsuitable for operation or refuse surgery and patients with oligometastatic NSCLC who are not suitable for surgery. As an immunologic agent, pembrolizumab has been approved to treat metastatic NSCLC in certain countries, including China and the United States. Increased tumor proportion score (TPS) can reduce pembrolizumab's immunotherapeutic effect, while SBRT can reduce TPS and enhance immunotherapy efficacy. However, there have been no reports in China on metastatic NSCLC patients who have received pembrolizumab monotherapy after stereotactic body radiotherapy (SBRT). Here, we present a case of progression-free survival (PFS) of nearly 5 years with pembrolizumab monotherapy after SBRT for metastatic NSCLC. This case is the patient with the most prolonged medication duration and who experienced the most efficacious treatment among the patients with metastatic NSCLC reported in the Chinese literature.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Anticorpos Monoclonais Humanizados , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , China , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Intervalo Livre de Progressão
18.
Entropy (Basel) ; 22(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33286016

RESUMO

Identifying a set of influential nodes is an important topic in complex networks which plays a crucial role in many applications, such as market advertising, rumor controlling, and predicting valuable scientific publications. In regard to this, researchers have developed algorithms from simple degree methods to all kinds of sophisticated approaches. However, a more robust and practical algorithm is required for the task. In this paper, we propose the EnRenew algorithm aimed to identify a set of influential nodes via information entropy. Firstly, the information entropy of each node is calculated as initial spreading ability. Then, select the node with the largest information entropy and renovate its l-length reachable nodes' spreading ability by an attenuation factor, repeat this process until specific number of influential nodes are selected. Compared with the best state-of-the-art benchmark methods, the performance of proposed algorithm improved by 21.1%, 7.0%, 30.0%, 5.0%, 2.5%, and 9.0% in final affected scale on CEnew, Email, Hamster, Router, Condmat, and Amazon network, respectively, under the Susceptible-Infected-Recovered (SIR) simulation model. The proposed algorithm measures the importance of nodes based on information entropy and selects a group of important nodes through dynamic update strategy. The impressive results on the SIR simulation model shed light on new method of node mining in complex networks for information spreading and epidemic prevention.

19.
Dis Markers ; 2020: 7347298, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163123

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the global mortality diseases and has a poor prognosis due to the lack of ideal tumor biomarkers. Numerous studies have shown that long noncoding RNAs (lncRNAs) can affect the occurrence and development of cancer through a variety of signaling pathways. The abnormal expression and specificity of lncRNAs in tumors make them potential biomarkers of cancers. Nevertheless, the diagnostic roles of lncRNAs in GC have been poorly understood. So this study focuses on the clinical diagnostic value of lncRNAs in GC. MATERIALS AND METHODS: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to investigate the expression of the linc-ROR (long intergenic noncoding RNA, regulator of reprogramming) in 105 paired GC tissues and adjacent normal tissues. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were established to assess the diagnostic value of linc-ROR. The relationship between expression of linc-ROR and clinicopathological factors of patients with GC was further explored. Kaplan-Meier analysis was performed to evaluate the prognostic value of linc-ROR expression. RESULTS: The linc-ROR expression level was significantly decreased in GC tissues compared with its adjacent nontumor tissues (n = 105, P < 0.001). We also discovered that linc-ROR was evidently downregulated in 68.6% (72/105) of GC tissues. The AUC's value of linc-ROR was up to 0.6495, with sensitivity and specificity of 0.7524 and 0.5143, respectively. Intriguingly, the linc-ROR expression levels were obviously associated with tumor differentiation (P = 0.004). Notably, the overall survival rate of GC patients with high expression of linc-ROR was significantly higher than those with low expression. CONCLUSION: Our data revealed that linc-ROR has clinical potential as a biomarker for the diagnosis of GC and assessment of its prognosis.


Assuntos
Biomarcadores Tumorais/genética , Regulação para Baixo , RNA Longo não Codificante/genética , Neoplasias Gástricas/diagnóstico , Área Sob a Curva , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Taxa de Sobrevida
20.
Small ; 16(45): e2003426, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33079468

RESUMO

Homogeneous graphene dispersions with tunable concentrations are fundamental prerequisites for the preparation of graphene-based materials. Here, a strategy for effectively dispersing graphene using graphene oxide (GO) to produce homogeneous, tunable, and ultrahigh concentration graphene dispersions (>150 mg mL-1 ) is proposed. The structure of GO with abundant edge-bound hydrophilic carboxyl groups and in-plane hydrophobic π-conjugated domains allows it to function as a special "surfactant" that enables graphene dispersion. In acidic solutions, GO sheets tend to form edge-to-edge hydrogen bonds and expose the π-conjugated regions which interact with graphene, thereby promoting graphene dispersion. While in alkaline solutions, GO sheets tend to stack in a surface-to-surface manner, thereby blocking the π-conjugated regions and impeding graphene dispersion. As the concentration of GO-dispersed graphene dispersion (GO/G) increases, a continuous transition between four states is obtained, including a dilute dispersion, a thick paste, a free-standing gel, and a kneadable, playdough-like material. Furthermore, GO/G can be applied to create desirable structures including highly conductive graphene films with excellent flexibility, thereby demonstrating an immense potential in flexible composite materials.

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