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Grain boundaries (GBs), with their diversity in both structure and structural transitions, play an essential role in tailoring the properties of polycrystalline materials1-5. As a unique GB subset, {112} incoherent twin boundaries (ITBs) are ubiquitous in nanotwinned, face-centred cubic materials6-9. Although multiple ITB configurations and transitions have been reported7,10, their transition mechanisms and impacts on mechanical properties remain largely unexplored, especially in regard to covalent materials. Here we report atomic observations of six ITB configurations and structural transitions in diamond at room temperature, showing a dislocation-mediated mechanism different from metallic systems11,12. The dominant ITBs are asymmetric and less mobile, contributing strongly to continuous hardening in nanotwinned diamond13. The potential driving forces of ITB activities are discussed. Our findings shed new light on GB behaviour in diamond and covalent materials, pointing to a new strategy for development of high-performance, nanotwinned materials.
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Moiré superlattices formed by twisted stacking in van der Waals materials have emerged as a new platform for exploring the physics of strongly correlated materials and other emergent phenomena1-5. However, there remains a lack of research on the mechanical properties of twisted-layer van der Waals materials, owing to a lack of suitable strategies for making three-dimensional bulk materials. Here we report the successful synthesis of a polycrystalline boron nitride bulk ceramic with high room-temperature deformability and strength. This ceramic, synthesized from an onion-like boron nitride nanoprecursor with conventional spark plasma sintering and hot-pressing sintering, consists of interlocked laminated nanoplates in which parallel laminae are stacked with varying twist angles. The compressive strain of this bulk ceramic can reach 14% before fracture, about one order of magnitude higher compared with traditional ceramics (less than 1% in general), whereas the compressive strength is about six times that of ordinary hexagonal boron nitride layered ceramics. The exceptional mechanical properties are due to a combination of the elevated intrinsic deformability of the twisted layering in the nanoplates and the three-dimensional interlocked architecture that restricts deformation from propagating across individual nanoplates. The advent of this twisted-layer boron nitride bulk ceramic opens a gate to the fabrication of highly deformable bulk ceramics.
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Traditional ceramics or metals cannot simultaneously achieve ultrahigh strength and high electrical conductivity. The elemental carbon can form a variety of allotropes with entirely different physical properties, providing versatility for tuning mechanical and electrical properties in a wide range. Here, by precisely controlling the extent of transformation of amorphous carbon into diamond within a narrow temperature-pressure range, we synthesize an in situ composite consisting of ultrafine nanodiamond homogeneously dispersed in disordered multilayer graphene with incoherent interfaces, which demonstrates a Knoop hardness of up to ~53 GPa, a compressive strength of up to ~54 GPa and an electrical conductivity of 670-1,240 S m-1 at room temperature. With atomically resolving interface structures and molecular dynamics simulations, we reveal that amorphous carbon transforms into diamond through a nucleation process via a local rearrangement of carbon atoms and diffusion-driven growth, different from the transformation of graphite into diamond. The complex bonding between the diamond-like and graphite-like components greatly improves the mechanical properties of the composite. This superhard, ultrastrong, conductive elemental carbon composite has comprehensive properties that are superior to those of the known conductive ceramics and C/C composites. The intermediate hybridization state at the interfaces also provides insights into the amorphous-to-crystalline phase transition of carbon.
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Lithium sulfur battery is a novel kind of secondary battery which has high energy density, however its application is greatly affected by the shuttle effect of polysulfides generated in the redox reaction of cathode electrode. Metal active sites are supposed as effective catalysts which can absorb and accelerate the conversion efficiency of lithium polysulfides, thus the shuttle effect will be alleviated. In this work, we conducted a simple way to prepare a metal Fe doped ketjen black to serve as the sulfur host of lithium sulfur battery. Ketjen black has a large specific surface area and rich porous structure, while Fe nanodot is an excellent catalyst for lithium polysulfides. Because of these advantages, the Fe/KB host can effectively confine a large amount of active material and accelerate its, therefore the Fe/KB-S cathode electrode show an excellent electrochemical performance.
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Novel materials displaying multiple exceptional properties are the backbone of the advancement of various industries. In the field of carbon materials, the combination of different properties has been extensively developed to satisfy diverse application scenarios, for instance, conductivity paired with exceptional hardness, outstanding toughness coupled with super-hardness, or heat resistance combined with super-hardness. In this work, a new carbon allotrope, bcc-C40 carbon, was predicted and investigated using first-principles calculations based on density functional theory. The allotrope exhibits unique structural features, including a combination of sp3 hybridized diatomic carbon and four-fold carbon chains. The mechanical and dynamic stability of bcc-C40 carbon has been demonstrated by its elastic constants and phonon spectra. Additionally, bcc-C40 carbon exhibits remarkable mechanical properties, such as zero homogeneous Poisson's ratio, superhardness with a value of 58 GPa, and stress-adaptive toughening. The analysis of the electronic properties demonstrates that bcc-C40 carbon is a semiconductor with an indirect band gap of 3.255 eV within the HSE06 functional, which increases with the increase in pressure. At a pressure of 150 GPa, bcc-C40 carbon transforms into a direct band gap material. These findings suggest the prospective use of bcc-C40 carbon as a superhard material and a novel semiconductor.
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Mechanical properties of covalent materials can be greatly enhanced with strategy of nanostructuring. For example, the nanotwinned diamond with an isotropic microstructure of interweaved nanotwins and interlocked nanograins shows unprecedented isotropic mechanical properties. How the anisotropic microstructure would impact on the mechanical properties of diamond has not been fully investigated. Here, we report the synthesis of diamond from superaligned multiwalled carbon nanotube films under high pressure and high temperature. Structural characterization reveals preferentially oriented diamond nanotwin bundles with an average twin thickness of ca. 2.9 nm, inherited from the directional nanotubes. This diamond exhibits extreme mechanical anisotropy correlated with its microstructure (e.g., the average Knoop hardness values measured with the major axis of the indenter perpendicular and parallel to nanotwin bundles are 233 ± 8 and 129 ± 9 GPa, respectively). Molecular dynamics simulation reveals that, in the direction perpendicular to the nanotwin bundles, the dense twin boundaries significantly hinder the motion of dislocations under indentation, while such a resistance is much weaker in the direction along the nanotwin bundles. Current work verifies the hardening effect in diamond via nanostructuring. In addition, the mechanical properties can be further tuned (anisotropy) with microstructure design and modification.
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OBJECTIVES: This research aimed to construct a prediction model for stages II and III cardia carcinoma (CC), and provide an effective preoperative evaluation tool for clinicians. METHODS: CC mRNA expression matrix was obtained from Gene Expression Omnibus and The Cancer Genome Atlas databases. Non-negative matrix factorization was used to cluster data to obtain subgroup information, and weighted gene co-expression network analysis was used to uncover key modules linked to different subgroups. Gene-set enrichment analysis analyzed biological pathways of different subgroups. The related pathways of multiple modules were scrutinized with Kyoto Encyclopedia of Genes and Genomes. Key modules were manually annotated to screen CC-related genes. Subsequently, quantitative real-time polymerase chain reaction assessed CC-related gene expression in fresh tissues and paraffin samples, and Pearson correlation analysis was performed. A classification model was constructed and the predictive ability was evaluated by the receiver operating characteristic curve. RESULTS: CC patients had four subgroups that were associated with brown, turquoise, red, and black modules, respectively. The CC-related modules were mainly associated with abnormal cell metabolism and inflammatory immune pathways. Then, 76 CC-elated genes were identified. Pearson correlation analysis presented that THBS4, COL14A1, DPYSL3, FGF7, and SVIL levels were relatively stable in fresh and paraffin tissues. The area under the curve of 5-gene combined prediction for staging was 0.8571, indicating good prediction ability. CONCLUSIONS: The staging classifier for CC based on THBS4, COL14A1, DPYSL3, FGF7, and SVIL has a good predictive effect, which may provide effective guidance for whether CC patients need emergency surgery.
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Carcinoma , Neoplasias Gástricas , Humanos , Cárdia , Parafina , Neoplasias Gástricas/genética , AlgoritmosRESUMO
Compared with traditional structure prediction methods, the purposeful bottom-up approach is better able to obtain structures with specified performance. In this study, we established two novel carbon phases in purely sp2-bonded networks, termed H61-carbon and H62-carbon, using a self-assembling approach. These carbyne-connected carbon allotropes had helix chains joined by cumulative double-bond chains. We certified the new carbon allotropes to be dynamically and mechanically stable. Both of these carbon allotropes exhibited excellent mechanical properties, and they had metallic and superconductive characteristics featuring superconducting transition temperatures of 10 K (H61-carbon) and 7.4 K (H62-carbon), respectively. These results provide an important strategy for the design of novel carbon allotropes with specified properties.
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The traditional hardness-toughness tradeoff poses a substantial challenge for the development of superhard materials. Due to strong covalent bonds and intrinsic brittleness, the full advantage of microstructure engineering for enhanced mechanical properties requires further exploration in superhard materials. Here heterogeneous diamond-cBN composites were synthesized from a carefully prepared precursor (hBN microflakes uniformly wrapped by onion carbon nanoparticles) through phase transitions under high pressure and high temperature. The synthesized composites inherit the architecture of the precursors: cBN regions with an anisotropic profile that spans several micrometers laterally and several hundred nanometers in thickness are embedded in a nanograined diamond matrix with high-density nanotwins. A significantly high fracture toughness of 16.9 ± 0.8 MPa m1/2 is achieved, far beyond those of single-crystal diamond and cBN, without sacrificing hardness. A detailed TEM analysis revealed multiple toughening mechanisms closely related to the microstructure. This work sheds light on microstructure engineering in superhard materials for excellent mechanical properties.
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BACKGROUND: Gastric cancer remains a major cause of cancer-related death worldwide. C12orf48, also named PARP1 binding protein, is over-expressed in several cancers. However, the expression profile and potential roles of C12orf48 in gastric cancer are largely unknown. METHODS: We used bioinformatics approaches and tissue microarray immunohistochemistry to analyze the expression profile of C12orf48 in gastric cancer tissues. Plasmid-mediated over-expression or knockdown were performed. CCK-8 assays and flow cytometry were employed to evaluate cellular proliferation and apoptosis respectively. Transwell assays were used to assess migrative and invasive abilities. The roles of C12orf48 were also evaluated in a xenograft tumor model. RESULTS: We found that C12orf48 was over-expressed in gastric cancer tissue, which associated with advanced stage and poor prognosis. In vitro and in vivo experiments showed depletion of C12orf48 attenuated cancer growth, while facilitated apoptosis. Further, the expression of Poly r(C)-Binding Protein (PCBP) 1 was found negatively regulated by C12orf48. Intended up-regulation of PCBP1 prevented C12orf48-mediated proliferation and rescued cells from apoptosis. Besides, C12orf48 promoted cellular migration and invasion, with E-cadherin down-regulated while vimentin and N-cadherin up-regulated, which was reversed by up-regulated PCBP1. CONCLUSIONS: Our findings indicate that depletion of C12orf48 inhibited gastric cancer growth and metastasis via up-regulating PCBP1. Targeting C12orf48-PCBP1 axis may be a potential therapeutic strategy.
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Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias Gástricas/genética , Apoptose/genética , Proliferação de Células/genética , Biologia Computacional , Regulação para Baixo/genética , Humanos , Metástase Neoplásica/genética , Processos Neoplásicos , Regulação para Cima/genéticaRESUMO
Ternary boron-carbon-nitrogen (B-C-N) compounds are considered to possess hardness comparable to diamond and thermal stability comparable to c-BN. Explorations for desirable B-C-N phases have been continuous. However, the nonconductive properties of most B-C-N compounds narrow the applications of these compounds. Herein, we propose a sp2-sp3 hybridized phase of t-B2C3N2, which consists of diamond-like BC blocks connected with single N-N bonds. Elastic constants and phonon dispersion curves confirm that t-B2C3N2 is mechanically and dynamically stable. The structure processes 2D metallicity in a strong 3D network. Furthermore, hardness and electron-phonon calculations reveal that t-B2C3N2 is superhard and superconductive with a superconducting critical temperature reaching 2.3 K.
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OBJECTIVE: Systemic chemotherapy has limited efficacy in the treatment of peritoneal metastasis (PM) in gastric cancer (GC). Hyperthermic intraperitoneal chemotherapy (HIPEC) combined with complete cytoreductive surgery (CRS) has shown promising outcomes but remains controversial. The present study aimed to evaluate the safety and efficacy of HIPEC without CRS in GC patients with PM. METHODS: This retrospective propensity score-matched multicenter cohort study included GC patients with PM treated with either chemotherapy alone (Cx group) or with HIPEC combined with chemotherapy (HIPEC-Cx group) in four Chinese high-volume gastric medical centers between 2010 and 2017. The primary outcomes were median survival time (MST) and 3-year overall survival (OS). Propensity score matching was performed to compensate for controlling potential confounding effects and selection bias. RESULTS: Of 663 eligible patients, 498 were matched. The MST in the Cx and HIPEC-Cx groups was 10.8 and 15.9 months, respectively [hazard ratio (HR)=0.71, 95% confidence interval (95% CI), 0.58-0.88; P=0.002]. The 3-year OS rate was 10.1% (95% CI, 5.4%-14.8%) and 18.4% (95% CI, 12.3%-24.5%) in the Cx and HIPEC-Cx groups, respectively (P=0.017). The complication rates were comparable. The time to first flatus and length of hospital stay for patients undergoing HIPEC combined with chemotherapy was longer than that of chemotherapy alone (4.6±2.4 dvs. 2.7±1.8 d, P<0.001; 14.2±5.8 dvs. 11.4±7.7 d, P<0.001), respectively. The median follow-up period was 33.2 months. CONCLUSIONS: Compared with standard systemic chemotherapy, HIPEC combined with chemotherapy revealed a statistically significant survival benefit for GC patients with PM, without compromising patient safety.
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Breath testing is a noninvasive method with potential for diagnosing cancers and has been regarded as one of the research hotspots in metabolomics. In the conventional breath sampling process, however, degradation of exhaled metabolites and introduction of impurities from sampling bags or tubes limit the development of breath research. To solve this problem, we previously developed an on-line breath sampling system, which can directly deliver exhaled gases from the mouth to the proton transfer reaction mass spectrometry (PTR-MS) breath analysis instrument. To establish a standard expiratory method for this system, four parameters that may affect the concentrations of exhaled volatile organic compounds (VOCs) were studied. We found inhaled gas volume, breath holding time, mouth rinsing, and ambient air all affected the exhaled VOCs. In particular, the breath holding time and mouth rinsing significantly affected the VOCs which originate from the oral cavity. Therefore, these four parameters should be taken into account in future on-line breath testing.
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Espectrometria de Massas , Prótons , Compostos Orgânicos Voláteis/análise , Testes Respiratórios , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: To evaluate the patterns of recurrence and the related factors in patients with pT3N0M0 thoracic esophageal squamous cell carcinoma (ESCC) after two-field esophagectomy. METHODS: From Jan 2008 to Dec 2009, 208 patients with stage pT3N0M0(2002, UICC) thoracic ESCC were treated with two-field esophagectomy in our hospital. There were 138 males and 70 females, and the median age was 60 years old (range 33-78). There were 33 patients in the upper-, 134 in the middle-, and 41 in the lower-thoracic esophagus, with a median length of lesion of 5 cm. There were 32 patients with no-, 78 with mild- and 98 patients with severe adhesions at surgery. The median number of dissected lymph nodes was 9 (range 1-27). 98 patients were treated with surgery alone and 110 with postoperative adjuvant chemotherapy. The statistical analysis was conducted using SPSS 13.0 software. RESULTS: The follow-up was ended on July 2013. In the total group of 208 patients, the total recurrence rate was 41.8% (87/208). Among them, 52 patients had locoregional recurrence (LR), 15 had distant metastasis (DM) and 20 patients had both local recurrence and distant metastasis. 40.2% (35/87) of all recurrences were found within one year after operation, 67.8% (59/87) within 2 years, 86.2% (75/87) within 3 years, and 100% (87/87) within 4 years. The 1-, 3-, and 5-year progression-free survival (PFS) rate was 83.0%, 62.8% and 56.3%, respectively. The overall locoregional recurrence rate was 34.6% (72/208), among them, 9 cases had recurrence in the cervix (all were supraclavicular lymph node metastasis), 66 cases in the mediastinum and 4 cases had para-aortic lymph node metastasis. 83.3% (60/72) of the locoregional recurrence was located in the carinal region or upper area. The 1-, 3-, 5-year locoregional recurrence rate was 15.6%, 32.2%, and 36.8%, respectively, and the median time of recurrence was 15.5 months. The overall distant metastasis (DM) rate was 16.8% (35/208). The 1-, 3-, and 5-year DM rate was 4.4%, 15.3%, and 20.1%, respectively, and the median time of DM was 24 months. The most common site of DM was the lung and bone. The univariate analysis showed that age and tumor site were associated with PFS, tumor site and small lymph node in the mediastinum (diamter <1 cm) before surgery were related with LR (P<0.05 for all), and tumor site, histological differentiation and LR were related with distant metastasis after surgery (P<0.05). Multivariate analysis showed that the tumor site was an independent prognostic factor affecting the progression-free survival and locoregional recurrence (P<0.05), and histological differentiation and LR were independent factors associated with distant metastasis (P<0.05 for all). CONCLUSIONS: The recurrence rate is very high in patients with pT3N0M0 thoracic ESCC after surgery, and most of them occur within 3 years after operation. Locoregional recurrence occurs more frequently and shortly than distant metastasis, and most of LR is located in the carinal region or upper-mediastinum. LR rate in upper-thoracic ESCC is very high, therefore, postoperative radiotherapy (PORT) is strongly suggested. LR rate in middle thoracic ESCC is also rather high and PORT is suggested. LR occur much less in the lower-thoracic ESCC, thus, PORT is not suggested routinely. Patients with poorly differentiated ESCC and LR have a high rate of distant metastasis.
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Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Quimioterapia Adjuvante , Intervalo Livre de Doença , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Excisão de Linfonodo , Linfonodos , Metástase Linfática , Masculino , Mediastino , Pessoa de Meia-Idade , Análise Multivariada , Pescoço , Estadiamento de Neoplasias , Período Pós-OperatórioRESUMO
Lung cancer is the leading cause of cancer-related death in the world. To explore tumor biomarkers for clinical application, two-dimensional fluorescence difference gel electrophoresis and subsequent MALDI-TOF/TOF mass spectrometry were performed to identify proteins differentially expressed in 12 pairs of lung squamous cell tumors and their corresponding normal tissues. A total of 28 nonredundant proteins were identified with significant alteration in lung tumors. The up-regulation of isocitrate dehydrogenase 1 (IDH1), superoxide dismutase 2, 14-3-3ε, and receptor of activated protein kinase C1 and the down-regulation of peroxiredoxin 2 in tumors were validated by RT-PCR and Western blot analysis in independent 15 pairs of samples. Increased IDH1 expression was further verified by the immunohistochemical study in extended 73 squamous cell carcinoma and 64 adenocarcinoma clinical samples. A correlation between IDH1 expression and poor overall survival of non-small cell lung cancer (NSCLC) patients was observed. Furthermore, ELISA analysis showed that the plasma level of IDH1 was significantly elevated in NSCLC patients compared with benign lung disease patients and healthy individuals. In addition, knockdown of IDH1 by RNA interference suppressed the proliferation of NSCLC cell line and decreased the growth of xenograft tumors in vivo. These observations suggested that IDH1, as a protein promoting tumor growth, could be used as a plasma biomarker for diagnosis and a histochemical biomarker for prognosis prediction of NSCLC.
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Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Isocitrato Desidrogenase/metabolismo , Proteoma/análise , Proteômica , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adulto , Idoso , Animais , Biomarcadores Tumorais/genética , Western Blotting , Brônquios/citologia , Brônquios/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Técnicas Imunoenzimáticas , Isocitrato Desidrogenase/genética , Pulmão/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Taxa de SobrevidaRESUMO
OBJECTIVE: To investigate the effect of NF-κB activation on radiation response of esophageal carcinoma. METHODS: The expression of NF-κB was detected in pretreatment and posttreatment specimens of patients with ESCC by immunohistochemistry. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activation of NF-κB in esophageal cancer cell line KYSE150 cells. SN50, a specific NF-κB inhibitor, was applied to inhibit the activation of NF-κB. Clone formation test was used to detect the radiosensitivity of esophageal cancer cells. RESULTS: The median survival time of patients with activated and inactivated NF-κB in the pretreatment specimens were 16 and 19 months, respectively, with a non-significant difference between the two groups (P > 0.05). As to the patients with activated and inactivated NF-κB in posttreatment specimens, the median survival times were 13 and 35 months, respectively, with a significant difference (P < 0.01) between them. Western blot showed that the cytoplasmic expression of NF-κB was reduced with increasing radiation dose at 1.5 and 3 hours after radiation treatment. However, the expression of NF-κB in the cell nuclei was increased under the same condition, showing a trend of increased nucleus/cytoplasm ratio. The clone number in SN50 group was 96.66, 64.66, 76.66 and 10.00 under 0, 2, 4 and 12 Gy irradiation, which demonstrated a significant difference compared with the control groups (P < 0.001). CONCLUSIONS: Our results show that activation of NF-κB is induced by radiotherapy. Activation of NF-κB reduces the outcome of radiation treatment of esophageal cancer patients.
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Neoplasias Esofágicas/radioterapia , NF-kappa B/metabolismo , Western Blotting , Linhagem Celular Tumoral , Núcleo Celular , Neoplasias Esofágicas/metabolismo , Humanos , Imuno-Histoquímica , Tolerância a Radiação , Transdução de SinaisRESUMO
INTRODUCTION: The role of lipid metabolism in lung adenocarcinoma (LUAD) is not completely researched. Lipid metabolism reprogramming is a characteristic of malignancies and contributes to carcinogenesis and progression. The transcriptome and scRNA- seq data and clinical information were downloaded from the public databases. METHODS: Lipid metabolism pathways were collected from the MSigDB database, and molecular subtypes were classified based on lipid metabolism features via consensus clustering. The bidirectional crosstalk between immune cells and malignant cells was analyzed. Differences in lipid metabolism at the single-cell level and their correlation with the tumor microenvironment (TME) were also studied. LUAD patients were classified into two subtypes, showing distinct mutation and lipid metabolism features based on lipid metabolism characteristics. Meanwhile, significant differences in the overall survival, clinical characteristics, and immune landscape were observed between the two subtypes. We also found that clust1 had higher oxidative stress status. There were 116 differentially expressed genes between the two subtypes, which were significantly associated with cell cycle progression. We identified 4001 immune cells, including 483 malignant cells and 3518 normal cells, and found active intercellular communication and significant differences in lipid metabolism characteristics between the malignant cells and normal cells. Furthermore, several lipid metabolism pathways were found to be associated with TME factors, including hypoxia and angiogenesis. RESULT: The current findings indicated that lipid metabolism was involved in the development and cellular heterogeneity of LUAD and revealed widespread reprogramming across multiple cellular elements in the TME of LUAD. CONCLUSION: This characterization improved the current understanding of tumor biology and enabled the identification of novel targets for immunotherapy.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Metabolismo dos Lipídeos , Adenocarcinoma de Pulmão/genética , Carcinogênese , Transcriptoma , Neoplasias Pulmonares/genética , Microambiente Tumoral , PrognósticoRESUMO
BACKGROUND: Esophagogastric junction cancer (EJC) refers to malignant tumors that develop at the junction between the stomach and the esophagus. TUSC1 is a recently identified tumor suppressor gene known for its involvement in various types of cancer. The objective of this investigation was to elucidate the regulatory influence of DNA methylation on TUSC1 expression and its role in the progression of EJC. METHODS: Bioinformatics software was utilized to analyze the expression of TUSC1, enriched pathways, and highly methylated sites in the promoter region. TUSC1 expression in EJC was assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blot (WB), and immunohistochemistry. Methylation-specific PCR was employed to detect the methylation level of TUSC1. To analyze the effects of TUSC1 and 5-AZA-2 on tumor cell proliferation, migration, invasion, cell cycle, and apoptosis, several assays including CCK-8, colony formation, transwell, and flow cytometry were conducted. The expression of MDM2 was assessed using qRT-PCR and WB. WB detected the expression of p53, and p-p53, markers for EJC cell proliferation, epithelial-mesenchymal transition, and apoptosis. The role of TUSC1 in tumor occurrence in vivo was examined using a xenograft mouse model. RESULTS: TUSC1 expression was significantly downregulated in EJC. Overexpression of TUSC1 and treatment with 5-AZA-2 inhibited the malignant progression of EJC cells. In EJC, low methylation levels promoted the expression of TUSC1. Upregulation of TUSC1 suppressed the expression of MDM2 and activated the p53 signaling pathway. Inactivation of this pathway attenuated the inhibitory effect of TUSC1 overexpression on EJC cell proliferation, migration, invasion, and other behaviors. Animal experiments demonstrated that TUSC1 overexpression inhibited EJC tumor growth and metastasis in vivo. CONCLUSION: TUSC1 was commonly downregulated in EJC and regulated by methylation. It repressed the malignant progression of EJC tumors by mediating the p53 pathway, suggesting its potential as a diagnostic and therapeutic target for EJC.
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Proliferação de Células , Metilação de DNA , Neoplasias Esofágicas , Regulação Neoplásica da Expressão Gênica , Proteínas Supressoras de Tumor , Humanos , Metilação de DNA/genética , Animais , Proteínas Supressoras de Tumor/genética , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/genética , Proliferação de Células/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Progressão da Doença , Junção Esofagogástrica/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Apoptose/genética , Regiões Promotoras Genéticas/genética , Proteína Supressora de Tumor p53/genética , Masculino , Movimento Celular/genética , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Camundongos NusRESUMO
The M/SSZ-39 catalysts (M = In, Co, Cu, Fe) with different metal species and metal loadings were synthesized using the wet impregnation method on a small-pore SSZ-39 molecular sieve. X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-dehydrogenation and hydrogen temperature program reduction (H2-TPR) were employed to characterize the effects of various metal components and metal loadings on the performance of CH4 selective catalytic reduction of NO reaction (CH4-SCR). The characterization results showed that the In/SSZ-39 catalyst exhibited significantly higher catalytic activity compared to the Cu-, Co-, and Fe/SSZ-39 catalysts, suggesting that indium (In) is a more suitable active ingredient for the CH4-SCR reaction. The xIn/SSZ-39 (x = 1, 2, 3, x represents the In loadings of 1.0 wt%, 2.0 wt% and 3.0 wt%) catalysts, with different In loadings, all present excellent CH4-SCR performance. By varying the In loadings, the type of In species present in the catalyst can be regulated, thus enhancing DeNOx activity and CH4 selectivity in the CH4-SCR reaction. At a low temperature of 400 °C and a low CH4/NO feed ratio (CH4/NO = 1), the 3In/SSZ-39 catalyst, featuring highly active InOx clusters, achieves the best low-temperature CH4-SCR performance, with a high NO conversion rate of up to 90% and a CH4 selectivity of up to 74.2%.
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The shuttle effect of soluble lithium polysulfide (LiPS) is a major obstacle to the practical application of lithium-sulfur (Li-S) batteries. In order to reduce the negative impact of the shuttle effect, Nd-MOF was combined with carbon nanofibers (CNFs) so that Nd-MOF was embedded in the CNFs and the Nd2O3-C/CNF composite was realized as a separation modification material. This embedded structure made the combination between Nd2O3-C and CNFs tighter, and it exhibited better synergistic effects to inhibit the shuttle effect of polysulfides while also enhancing the tensile strength of the separator and improving the safety performance of the battery. Based on these advantages, a lithium-sulfur coin cell with the Nd2O3-C/CNF-modified separator exhibited excellent electrochemical performance.