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1.
Environ Sci Pollut Res Int ; 31(15): 22847-22857, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38411908

RESUMO

Plastic aging can cause alterations in the physical and chemical characteristics of plastics, as well as their behavior in the environment. Due to the extremely slow natural aging process, laboratory simulated aging methods have to be used. In this study, non-thermal plasma (NTP) was adopted to investigate the aging process of polypropylene (PP) and polyethylene terephthalate (PET) microplastics. Various analytical instruments, including proton transfer reaction mass spectrometry and single-particle aerosol mass spectrometry, were employed to examine and identify the organic constituents of the gas, liquid, and particle phase degradation products, as well as to monitor the degradation process. The results showed that after 90 min of aging, both PP and PET surfaces showed yellowing, and the carbonyl index of PP increased while that of PET decreased, with an increase in crystallinity. The organic components of reaction products, such as ketones, esters, acids, and alcohols, increased with longer aging times. Gas products mainly contain aromatic hydrocarbons, while particles from aged PET contain compounds with benzene rings and metal elements. Liquid products from aged PP show a significant presence of branched alkanes. Based on this analysis, degradation mechanisms of PP and PET by NTP were proposed. This investigation represents the initial systematically exploration of the release of organic substances during the degradation of microplastics mediated by NTP. It provides significant insights into the detrimental organic compounds emitted during this process, thereby offering valuable information for understanding the environmental and human health implications of natural microplastic degradation. Furthermore, it addressed the requirements for increased attention to the potential environmental risks associated with these harmful components.


Assuntos
Polipropilenos , Poluentes Químicos da Água , Humanos , Idoso , Polipropilenos/química , Plásticos/análise , Microplásticos , Poluentes Químicos da Água/análise , Envelhecimento , Polietilenotereftalatos , Monitoramento Ambiental/métodos
2.
Inorg Chem ; 63(2): 1488-1498, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38175157

RESUMO

The crystal plane effect has gained extensive attention in heterogeneous catalysis reactions; however, it is far from being systematically probed in titanium dioxide (TiO2)-supported vanadium catalysts. Herein, a series of vanadium (V) single atoms and clusters anchored on TiO2 with different crystal planes was fabricated by an improved "top-down" protocol. The dispersion state, electronic structure, and redox properties of the V single-atom and VOx cluster-supported catalysts were systematically analyzed by a series of characterization methods, including X-ray absorption near edge structure (XANES) and density functional theory (DFT) calculations, and their catalytic performances were examined for aerobic oxidative desulfurization (AODS) of 4,6-dimethyl-dibenzothiophen (4,6-DMDBT) with O2 as the oxidant. The results unveiled that the synergistic effect between the V single atom and the VOx cluster perceptibly promoted the catalytic performances of VOx/TiO2 samples. Therein, VOx/TiO2-(001) shows the lowest apparent activation energy (Ea) value of 46.3 kJ/mol and the optimal AODS performance with complete 4,6-DMDBT conversion to 4,6-dimethyldibenzothiophene sulfone (4,6-DMDBTO2) within 60 min at 120 °C as compared with VOx/TiO2-(101) (81.9 kJ/mol and 180 min) and VOx/TiO2-(100) (68.0 kJ/mol and 240 min), which should be attributed to its higher V5+/V4+ ratio, the optimal redox behavior of the V species, the moderate adsorption energy between 4,6-DMDBT and VOx active centers, and the synthetic effect of V single atoms and VOx clusters. Moreover, VOx/TiO2-(001) exhibits robust durability in seven cycles of reuse, showcasing the potential for practical applications in the future.

3.
Inorg Chem ; 62(49): 20050-20061, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37989485

RESUMO

In this contribution, we rationally designed and controllably fabricated a NiMo/Al2O3-montmorillonite (3D-NiMo/Al2O3-MMT) monolithic catalyst via a 3D printing strategy with economical montmorillonite (MMT) as a binder. The catalytic performance of the resulting NiMo/Al2O3-MMT for 4,6-dimethyldibenzothiophene (4,6-DMDBT) hydrodesulfurization (HDS) was evaluated. The experimental results unveil that the 3D-NiMo/Al2O3-MMT monolithic catalyst exhibits robust stability and exceptional HDS activity with 99.2% 4,6-DMDBT conversion (residual 4 ppm of S), which is remarkably superior to that of conventional NiMo/Al2O3 (61.5%), NiMo/MMT (63.2%), and even NiMo/Al2O3-MMT (76.5%) prepared by the mechanical-mixing method. This should be ascribed to the synthetic effect between the MMT binder and the Al2O3 substrate, which effectively weakens the interaction between the Mo species and the Lewis acids on the original Al2O3 surface, thereby significantly increasing the content of reducible Mo species and considerably facilitating the formation of more highly active NiMoS phase (Type II) with optimal average stacking layers and thereafter remarkably enhancing the ultradeep HDS activity of the 3D-NiMo/Al2O3-MMT monolithic catalyst.

4.
ACS Appl Mater Interfaces ; 15(28): 33593-33604, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37431547

RESUMO

The development of a competitive-cost and high-efficiency NiMo/Al2O3 hydrodesulfurization (HDS) catalyst remains challenging in the field of petrochemical industry. Herein, a highly efficient NiMo/Al2O3 monolithic HDS catalyst was elaborately designed and successfully fabricated via a one-pot three-dimensional (3D) printing strategy, and its HDS activity was examined for 4,6-dimethyldibenzothiophene conversion. The results unveil that the NiMo/Al2O3 monolithic catalyst prepared by the 3D printing strategy (3D-NiMo/Al2O3) exhibits hierarchical structure due to the combustion of hydroxymethyl cellulose serving as adhesive, which endows the weaker metal-support-interaction between Mo oxides and Al2O3, remarkably promoting sulfidation of both Mo and Ni species and the formation of "Type II" NiMoS active phase, thereby reducing the apparent activation energy (Ea = 109.2 kJ·mol-1) and increasing the catalytic activity (TOF = 4.0 h-1) and thereafter dramatically boosting the HDS performance of 3D-NiMo/Al2O3 compared with that of NiMo/Al2O3 (Ea = 150.6 kJ·mol-1 and TOF = 2.1 h-1) counterpart synthesized by conventional method with P123 serving as the mesoporous template. Therefore, this study offers a facile and straightforward strategy to fabricate an efficient HDS catalyst with hierarchical structures.

5.
Inorg Chem ; 62(28): 11044-11055, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37414580

RESUMO

The design and preparation of catalysts with both excellent stability and maximum exposure of catalytic active sites is highly desirable; however, it remains challenging in heterogeneous catalysis. Herein, a entropy-stabilized single-site Mo catalyst via a high-entropy perovskite oxide LaMn0.2Fe0.2Co0.2Ni0.2Cu0.2O3 (HEPO) with abundant mesoporous structures was initiated by a sacrificial-template strategy. The presence of electrostatic interaction between graphene oxide and metal precursors effectively inhibits the agglomeration of precursor nanoparticles in a high-temperature calcination process, thereby endowing the atomically dispersed Mo6+ coordinated with four O atoms on the defective sites of HEPO. The unique structure of single-site Mo atoms' random distribution with an atomic scale greatly enriches the oxygen vacancy and increases surface exposure of the catalytic active sites on the Mo/HEPO-SAC catalyst. As a result, the obtained Mo/HEPO-SAC exhibits robust recycling stability and ultra-high oxidation activity (turnover frequency = 3.28 × 10-2) for the catalytic removal of dibenzothiophene (DBT) with air as the oxidant, which represents the top level and is strikingly higher than the state-of-the-art oxidation desulfurization catalysts reported previously under the same or similar reaction conditions. Therefore, the finding here for the first time expands the application of single-atom Mo-supported HEPO materials into the field of ultra-deep oxidative desulfurization.

6.
J Hazard Mater ; 458: 131870, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37379592

RESUMO

Plastic aging occurs in all environmental media and affects their environmental behavior and toxicity. In this study, non-thermal plasma was applied to simulate the aging process of plastics, with polyethylene terephthalate (PET-film) being used as a model. The surface morphology, mass defects, toxicity of aged PET-film and the generation of airborne fine particles were comprehensively characterized. The surface of PET films began to become rough and then gradually became uneven, generating pores, protrusions and cracks. The toxicity of aged PET films was assessed in Caenorhabditis elegans which significantly reduced head thrashing, body bending and brood size. A single particle aerosol mass spectrometry instrument was used to characterize the size distribution and chemical composition of airborne fine particles in real-time. Few particles were observed during the first 90 min, while the generation of particles accelerated significantly after aging time beyond 90 min. For two pieces of PET film with surface area of 5 cm2, during the 180 min, at least 15113 ± 153 fine particles were generated, having a unimodal size distribution with a peak of 0.4 µm. The main components of these particles included metals, inorganic non-metals, and organic components. The results provide useful information on plastic aging and are beneficial in assessing the potential environmental risks.

7.
Br J Haematol ; 201(6): 1116-1124, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37004981

RESUMO

Molecular recurrence (MRec) occurs in about half of all patients with chronic myeloid leukaemia (CML) who discontinue tyrosine kinase inhibitors (TKI) in sustained deep molecular response. A second TKI discontinuation has been attempted in some patients who regain the discontinuation criteria after resuming treatment. Nilotinib treatment affords faster and deeper molecular responses than imatinib as first-line therapy. We prospectively evaluated the efficacy and safety of nilotinib (300 mg twice daily) in chronic-phase CML patients who experienced MRec, after imatinib discontinuation and analysed the probability of TFR after a new attempt in patients treated for 2 years with sustained MR4.5 for at least 1 year. A total of 31 patients were included in the study between 2013 and 2018. Seven (23%) patients experienced serious adverse events after a median of 2 months of nilotinib treatment leading to discontinuation of treatment. One patient was excluded from the study for convenience. Among the 23 patients treated for 2 years with nilotinib, 22 maintained their molecular response for at least 1 year (median: 22 months) and stopped nilotinib. The TFR rates at 24 and 48 months after nilotinib discontinuation were 59.1% (95% confidence interval [CI]: 41.7%-83.7%) and 42.1% (95% CI: 25%-71%) respectively (NCT #01774630).


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Inibidores de Proteínas Quinases , Humanos , Mesilato de Imatinib/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Resultado do Tratamento
8.
J Colloid Interface Sci ; 629(Pt B): 569-580, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36179577

RESUMO

High entropy oxides are promising catalysts for numerous catalytic oxidation processes with oxygen as the oxidant. However, most of them often show bulk morphologies, which hinders the full exposure of active sites. In this work, a unique 26-faceted polyhedral high entropy oxide MnNiCuZnCoOx-1000 (P-HEO) with highly active site exposure is fabricated via a mechanochemistry-assisted strategy. By employing such a strategy, the supersaturation of P-HEO during the crystal growth process is effectively reduced to form high-index facets, which is proved to be beneficial to the formation of high-index facets. Characterization results indicate that more oxygen vacancies are generated in P-HEO compared with the bulk counterparts. Density functional theory calculations reveal that the high-index facets {-211} can facilitate adsorption and activation of O2 because of the higher adsorption energy -2.23 eV compared with that of (111) surfaces (-1.79 eV), which induces significantly enhanced activity for organic sulfides oxidation. Interestingly, the synthesized P-HEO with high-index facets shows a 98.4% removal rate of dibenzothiophene from model oil within 8 h at 120 °C, which is much higher than that of the bulk counterparts (33.5%).

9.
Front Genet ; 13: 873218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353113

RESUMO

Hepatocellular carcinoma (HCC) remains one of the most lethal cancers around the world. Precision oncology will be crucial for further improving the prognosis of HCC patients. Compared with traditional bulk RNA-seq, single-cell RNA sequencing (scRNA-seq) enables the transcriptomes of a great deal of individual cells assayed in an unbiased manner, showing the potential to deeply reveal tumor heterogeneity. In this study, based on the scRNA-seq results of primary neoplastic cells and paired normal liver cells from eight HCC patients, a new strategy of machine learning algorithms was applied to screen core biomarkers that distinguished HCC tumor tissues from the adjacent normal liver. Expression profiles of HCC cells and normal liver cells were first analyzed by maximum relevance minimum redundancy (mRMR) to get a top 50 signature gene feature. For further analysis, the incremental feature selection (IFS) method and leave-one-out cross validation (LOOCV) were conducted to build an optimal classification model and to extract 21 potentially essential biomarkers for HCC cells. Our results provided new insights into HCC pathogenesis that might be valuable for HCC diagnosis and therapy.

10.
Haematologica ; 107(12): 2859-2869, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35615931

RESUMO

Discontinuation of tyrosine kinase inhibitors in chronic phase chronic myeloid leukemia is feasible in clinical practice based on recently published international recommendations. Nevertheless, factors predictive of molecular recurrence have not been fully elucidated and long-term follow-up of patients enrolled in clinical studies are required in order to update knowledge on discontinuation attempts particularly in terms of the safety and durability of treatment-free remission (TFR). In the current study, we updated results from the STIM2 study in the light of the consensual criterion of molecular recurrence reported in different international recommendations. Among the 199 patients included in the perprotocol study, 108 patients lost a major molecular response. With a median follow-up of 40.8 months (5.5-111 months), the probability of treatment-free remission was 43.4% [36.3-50.4] at 5 years, 40.9% [32.8-47.3] at 7 years and 34.5% [25.6- 43.3] at 9 years. Molecular recurrence occurred between 0 to 6 months, 6 to 24 months and after 24 months in 75 patients (69%), 15 patients (14%) and 18 patients (17%), respectively. Notably, the kinetics of molecular recurrence differed significantly between these three subgroups with a median time from loss of MR4 (BCR::ABL1 IS≤0.01%) to loss of major molecular response of 1, 7 and 22 months, respectively. Predictive factors of molecular recurrence differed according to the time of occurrence of the molecular recurrence. Durations of imatinib treatment and deep molecular response as well as BCR::ABL1/ABL1 levels at cessation of tyrosine kinase inhibitor treatment, as quantified by reverse transcriptase droplet digital polymerase chain reaction, are involved in molecular recurrence occurring up to 24 months but not beyond. (ClinicalTrial. gov Identifier NCT#0134373).


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide de Fase Crônica , Humanos , Proteínas de Fusão bcr-abl/genética , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Indução de Remissão , Molécula 2 de Interação Estromal , Resultado do Tratamento
11.
J Oncol ; 2022: 8259951, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444701

RESUMO

Epithelial-mesenchymal transition (EMT) can promote carcinoma progression by multiple mechanisms; many studies demonstrated the invasiveness of pancreatic adenocarcinoma (PAAD) associated with the EMT, but how it acts through an lncRNA-dependent manner is unknown. Here, we investigated 146 samples from The Cancer Genome Atlas (TCGA) and 92 samples from the International Cancer Genome Consortium (ICGC). By gene set variation analysis (GSVA) and weighted correlation network analysis (WGCNA), we explored the EMT-related long noncoding RNAs (EMTlnc). Then, we performed univariate Cox regression analysis to screen their prognostic value for PAAD. The least absolute contraction and selection operator (LASSO) Cox regression was used to establish EMT-related lncRNA prognostic signal (EMT-LPS). In addition, we established a competitive endogenous ceRNA network. Then, we identified 33 prognostic EMTlnc as prognostic lncRNAs and established an EMT-LPS which showed strong prognostic ability in stratification analysis. By corresponding risk scores, patients were divided into low-risk and high-risk subgroups. Principal component analysis (PCA) showed that these subgroups had individual EMT status. Enrichment analysis showed that in the high-risk subgroup, biological processes, pathways, and hallmarks related to malignant tumors are more common. What is more, we constructed a nomogram that had powerful ability to predict the overall survival rate (OS) of PAAD patients in two datasets. So, EMT-LPS are a principal element in PAAD's carcinoma progression and may help us in choosing the way of prognosis assessment and provide some clues to design the new drugs for PAAD.

12.
Chemosphere ; 298: 134291, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35283155

RESUMO

A convenient technique for direct solids analysis, laser ablation single particle aerosol mass spectrometry (LA-SPAMS), was used to investigate lead and other components in soil and bark samples from around a battery industrial park. In total, over 50,000 particles ranging in size from 0.2 to 2 µm were sampled and approximately 15-35% of the particles were analyzed for chemical composition. The mean mass spectrum results showed that the intensity of lead varied widely among sampling points, reaching the highest intensity in the topsoil and bark at sampling point 4, located closest to the core factory. Based on the neural network algorithm of adaptive resonance theory (ART-2a), the topsoil and bark samples were classified into five categories: crustal composition (Ca+, silicates, aluminates, etc.), elemental carbon (C2-, C3-, C4-, etc.), organic carbon (CN-, levoglucosan, etc.), secondary inorganic sources (phosphates, nitrates, sulfates), and heavy metals (Pb+, Zn+, Cu+), with the proportion of Pb varying from 0.020 to 0.25% and 0.030-9.41% in topsoil and bark samples, respectively, while the proportion of Cu and Zn in topsoil and bark samples did not differ as greatly as Pb. In addition, the particle number concentrations of lead particles in topsoil and bark ranged from 0.14 to 3.48% and 0.36-37.93%, respectively. The concentrations of Pb in topsoil and bark samples measured by ICP-OES varied from 71 to 791 ppm and 172-2595 ppm, respectively. Overall, both the lead content in topsoil samples measured by LA-SPAMS and ICP-OES reached maximum values at sampling points 4 and 5, respectively, indicating moderate pollution with Pb at these two sites. This convenient LA-SPAMS method not only accurately detects the composition of solid samples, the mixing state of particulate matter, and the analytical component sources, but also omits tedious pretreatment steps, reduces the use of organic solvents, and shortens the detection time of solid samples, thereby providing an attractive method for soil environmental quality monitoring.


Assuntos
Poluentes Atmosféricos , Terapia a Laser , Metais Pesados , Poluentes do Solo , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental , Chumbo/análise , Espectrometria de Massas/métodos , Metais Pesados/análise , Solo , Poluentes do Solo/análise
13.
Int J Biol Sci ; 18(1): 360-373, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34975338

RESUMO

Immunotherapy has made great progress in hepatocellular carcinoma (HCC), yet there is still a lack of biomarkers for predicting response to it. Cancer stem cells (CSCs) are the primary cause of the tumorigenesis, metastasis, and multi-drug resistance of HCC. This study aimed to propose a novel CSCs-related cluster of HCC to predict patients' response to immunotherapy. Based on RNA-seq datasets from The Cancer Genome Atlas (TCGA) and Progenitor Cell Biology Consortium (PCBC), one-class logistic regression (OCLR) algorithm was applied to compute the stemness index (mRNAsi) of HCC patients. Unsupervised consensus clustering was performed to categorize HCC patients into two stemness subtypes which further proved to be a predictor of tumor immune microenvironment (TIME) status, immunogenomic expressions and sensitivity to neoadjuvant therapies. Finally, four machine learning algorithms (LASSO, RF, SVM-RFE and XGboost) were applied to distinguish different stemness subtypes. Thus, a five-hub-gene based classifier was constructed in TCGA and ICGC HCC datasets to predict patients' stemness subtype in a more convenient and applicable way, and this novel stemness-based classification system could facilitate the prognostic prediction and guide clinical strategies of immunotherapy and targeted therapy in HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Imunoterapia/métodos , Neoplasias Hepáticas/terapia , Aprendizado de Máquina , Células-Tronco Neoplásicas/patologia , Carcinoma Hepatocelular/genética , Biologia Computacional , Humanos , Neoplasias Hepáticas/genética , Prognóstico
14.
ACS Appl Mater Interfaces ; 14(1): 2246-2254, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34978411

RESUMO

It is well known that the existence of interstitial Fe is a great obstacle to enhancing the superconducting properties of the Fe(Se, Te) system. In this work, a silver and oxygen codoping effect toward enhancement of the superconductivity and flux pinning in Fe(Se, Te) bulks is reported. The oxygen ions from SeO2 can induce the precipitation of interstitial Fe as Fe2O3, thus simultaneously optimizing the superconducting properties of Fe(Se, Te) and forming extra flux pinning centers, while the existence of Ag can enhance the intergrain connections of the polycrystalline material by improving the electron transport at grain boundaries. Compared with the undoped sample, the critical current density, the upper critical field, and the thermally activated flux flow activation energy are greatly enhanced by 4.7, 1.7, and 1.5 times, respectively. The novel synthesis technique and optimized properties of this work can pave the way for the development of high-performance Fe(Se, Te) superconducting wires or tapes.

15.
Environ Sci Pollut Res Int ; 29(2): 2480-2492, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34374012

RESUMO

Non-thermal plasma (NTP) is gaining attention as a powerful tool to induce various reactions. The combination of NTP with catalysts has been successfully used to degrade volatile organic compounds (VOCs) for pollution control. In this study, a series of TiO2-C/5A catalysts, synthesized by carbon dots (C-dots) that decorate TiO2 by sol-gel and wetness impregnation methods, were incorporated with a dielectric barrier discharge (DBD) reactor in a single-stage structure to degrade toluene at atmospheric pressure and room temperature. A proton-transfer reaction mass spectrometer and a CO2 analyzer were used to monitor the concentration variations of organic by-products and CO2 online. The effects of input power, mass ratio of C-dots/TiO2 (TiO2/5A (0 wt%), TiO2-C1/5A (2.5 wt%), TiO2-C2/5A (5 wt%), TiO2-C3/5A (10 wt%)), gas flow rate, initial concentration of toluene on the toluene degradation efficiency, and CO2 selectivity were studied. The plasma-catalyst hybrid system could effectively improve the energy efficiency and reaction selectivity, attaining a maximum toluene degradation efficiency of 99.6% and CO2 selectivity of 83.0% compared to 79.5% and 37.5%, respectively, using the conventional plasma alone. Moreover, the generation of organic by-products also declined dramatically, averaging only half as much in plasma alone. The results also indicated that the appropriate amount of C-dot doping could greatly improve the catalyst efficiency in the hybrid plasma system. This is because the interaction between C-dots and TiO2 favors the formation of photoelectron holes and reduces the energy band gap and the recombination rate of photogenerated electron holes, which facilitates the generation of more active species on the catalyst surface, thereby leading to a more effective degradation reaction. These observations will provide guidance for the interaction studies between NTP and catalysts, not only for the exploration of new chemical mechanisms of aromatic compounds, but also for the screening of favorable materials for the desired reactions.


Assuntos
Gases em Plasma , Catálise , Titânio , Tolueno
16.
Front Immunol ; 13: 1031184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36601127

RESUMO

Background: Pancreatic cancer (PC) is one of the most lethal malignancies and carries a dismal mortality and morbidity. Four types of RNA modification (namely m6A, m1A, APA and A-to-I) could be catalyzed by distinct enzymatic compounds ("writers"), mediating numerous epigenetic events in carcinogenesis and immunomodulation. We aim to investigate the interplay mechanism of these writers in immunogenomic features and molecular biological characteristics in PC. Methods: We first accessed the specific expression pattern and transcriptional variation of 26 RNA modification writers in The Cancer Genome Atlas (TCGA) dataset. Unsupervised consensus clustering was performed to divide patients into two RNA modification clusters. Then, based on the differentially expressed genes (DEGs) among two clusters, RNA modification score (WM_Score) model was established to determine RNA modification-based subtypes and was validated in International Cancer Genome Consortium (ICGC) dataset. What's more, we manifested the unique status of WM_Score in transcriptional and post-transcriptional regulation, molecular biological characteristics, targeted therapies and immunogenomic patterns. Results: We documented the tight-knit correlations between transcriptional expression and variation of RNA modification writers. We classified patients into two distinct RNA modification patterns (WM_Score_high and _low), The WM_Score_high subgroup was correlated with worse prognosis, Th2/Th17 cell polarization and oncogenic pathways (e.g. EMT, TGF-ß, and mTORC1 signaling pathways), whereas the WM_Score_low subgroup associated with favorable survival rate and Th1 cell trend. WM_Score model also proved robust predictive power in interpreting transcriptional and post-transcriptional events. Additionally, the potential targeted compounds with related pathways for the WM_Score model were further identified. Conclusions: Our research unfolds a novel horizon on the interplay network of four RNA modifications in PC. This WM_Score model demonstrated powerful predictive capacity in epigenetic, immunological and biological landscape, providing a theoretical basis for future clinical judgments of PC.


Assuntos
Neoplasias Pancreáticas , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Neoplasias Pancreáticas/genética , Carcinogênese , Análise por Conglomerados , Neoplasias Pancreáticas
17.
Adv Mater ; 33(40): e2102575, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34397118

RESUMO

Owing to high intrinsic figure-of-merit implemented by multi-band valleytronics, GeTe-based thermoelectric materials are promising for medium-temperature applications. Transition metals are widely used as dopants for developing high-performance GeTe thermoelectric materials. Herein, relevant work is critically reviewed to establish a correlation among transition metal doping, electronic quality factor, and figure-of-merit of GeTe. From first-principle calculations, it is found that Ta, as an undiscovered dopant in GeTe, can effectively converge energy offset between light and heavy conduction band extrema to enhance effective mass at high temperature. Such manipulation is verified by the increased Seebeck coefficient of synthesized Ge1- x - y Tax Sby Te samples from 160 to 180 µV K-1 at 775 K upon doping Ta, then to 220 µV K-1 with further alloying Sb. Characterization using electron microscopy also reveals the unique herringbone structure associated with multi-scale lattice defects induced by Ta doping, which greatly hinder phonon propagation to decrease thermal conductivity. As a result, a figure-of-merit of ≈2.0 is attained in the Ge0.88 Ta0.02 Sb0.10 Te sample, reflecting a maximum heat-to-electricity efficiency up to 17.7% under a temperature gradient of 400 K. The rationalized beneficial effects stemming from Ta doping is an important observation that will stimulate new exploration toward high-performance GeTe-based thermoelectric materials.

18.
Kidney Int ; 100(4): 837-849, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34175352

RESUMO

Podocyte injury or dysfunction plays an essential role in causing proteinuria and glomerulosclerosis in chronic kidney diseases. To search for new players involved in podocyte injury, we performed gene expression profiling in the glomeruli by RNA sequencing. This unbiased approach led us to discover matrix metalloproteinase-10 (MMP-10), a secreted zinc-dependent endopeptidase, as one of the most upregulated genes after glomerular injury. In animal models and patients with proteinuric chronic kidney diseases, MMP-10 was upregulated specifically in the podocytes of injured glomeruli. Patients with chronic kidney diseases also had elevated circulating levels of MMP-10, which correlated with the severity of kidney insufficiency. In transgenic mice with podocyte-specific expression of MMP-10, proteinuria was aggravated after injury induced by Adriamycin. This was accompanied by more severe podocytopathy and glomerulosclerotic lesions. In contrast, knockdown of MMP-10 in vivo protected mice from proteinuria, restored podocyte integrity and reduced kidney fibrosis. Interestingly, MMP-10 reduced podocyte tight junctional protein zonula occludens-1 (ZO-1) but did not affect its mRNA level. Incubation of purified ZO-1 with MMP-10 directly resulted in its proteolytic degradation in vitro, suggesting ZO-1 as a novel substrate of MMP-10. Thus, our findings illustrate that induction of MMP-10 could lead to podocyte injury by degrading ZO-1, thereby promoting proteinuria and glomerulosclerosis in chronic kidney diseases.


Assuntos
Podócitos , Insuficiência Renal Crônica , Animais , Humanos , Glomérulos Renais , Metaloproteinase 10 da Matriz/genética , Camundongos , Proteinúria/induzido quimicamente , Proteinúria/genética , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/genética
19.
Chem Commun (Camb) ; 57(30): 3676-3679, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33725083

RESUMO

High-entropy crystalline materials are attracting more attention. In principle, high-entropy metal carbides (HMCs) that contain five or more metal ions, possess more negative free energy value during catalysis. But its preparation is challenging because of the immiscibility of multi metal cations in a single carbide solid solution. Here, a rational strategy for preparing HMC is proposed via a coordination-assisted crystallization process in the presence of Br-based poly(ionic liquids). Through this method, Mo0.2W0.2V0.2Cr0.2Nb0.2C nanoparticles, with a single cubic phase structure, incorporated on porous carbon, are obtained (HMC@NC). By combination of well dispersed small particle size (∼4 nm), high surface area (∼270 m2 g-1), and high-entropy phase, HMC@NC can function as a promising catalyst for the dehydrogenation of ethylbenzene. Unexpected activity (EB conv.: 73%) and thermal stability (>100 h on steam) at 450 °C are observed. Such a facile synthetic strategy may inspire the fabrication of other types of HMCs for more specific tasks.

20.
J Mass Spectrom ; 56(4): e4629, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32767454

RESUMO

A new atmospheric pressure ionization method, plasmaspray ionization, termed as PSI, was developed to be an alternative ambient ion source for mass spectrometry. It comprises a plasma jet device and a sample spray part. While the nonthermal plasma jet strikes the surface of stainless steel tube out of the spray capillary, the sprayed sample will be ionized with the assistant of auxiliary gas. Although PSI is a little bit more complex than electrospray ionization (ESI) in instrument, it shows both better linearity and higher sensitivity for organic compounds. For protein samples, it presents wider distributions of multiply charged ions and higher mass resolution without sacrificing any sensitivity. For the mechanism of PSI, the charge build-up process on the tip of capillary should play a key role for the ion formation, and the stimulated pulsed voltage on the flow tube will promote the ion aggregation speed until the charge density is high enough. PSI source contains the features of plasma ionization and ESI and can be considered as a novel combo bridging these techniques. These results reflect that this method of PSI can be applied and further developed as a versatile new ion source for a wild range of organic and biological samples.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Proteínas/análise , Ionização do Ar , Pressão Atmosférica , Cafeína/análise , Lecitinas/análise , Polímeros/análise , Propilenoglicóis/análise , Reserpina/análise
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