Mechanochemical bead-milling is a promising post-synthetic way to generate nanocrystalline zeotype materials with promoted catalytic performance. Post-milling recrystallization is often entailed to ...remedy the damaged framework but leads to crystal growth. Herein, using SAPO-34 (ca. 20 µm) derived from inexpensive morpholine as an example, we showcase that secondary growth can be suppressed by porogen-assisted recrystallization, resulting in formation of tiny crystals (100–200 nm) with better mass transport property. The presence of porogen (polydiallyldimethylammonium chloride) also induced a reduction of acid site density owing to a re-distribution of Si across the crystal, which alleviated zoning of Si at the external surface. The catalytic advantages, with respect to a control sample recrystallized in the absence of porogen, have been experimentally verified in dimethyl ether-to-olefin conversion, exhibiting an exaggerated light olefin selectivity and prolonged catalyst lifetime. This advancement of mechanochemical synthesis opens an avenue to better tailor crystal size for zeotype materials.
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•Combined bead-milling and porogen-assisted recrystallization method is developed to generate uniform SAPO-34 nanocrystals.•Secondary growth in the recrystallization process is suppressed by the presence of porogen.•Silicon zoning at the external surface is alleviated after recrystallization.•Enhanced diffusion property and high turnover number in dimethyl ether-to-olefin conversion are achieved.•Exaggerated light olefin selectivity and slowed coking rate are attained.
Background
Glutamine (Gln) metabolism has been reported to play an essential role in cancer. However, a comprehensive analysis of its role in lung adenocarcinoma is still unavailable. This study ...established a novel system of quantification of Gln metabolism to predict the prognosis and immunotherapy efficacy in lung cancer. Further, the Gln metabolism in tumor microenvironment (TME) was characterized and the Gln metabolism-related genes were identified for targeted therapy.
Methods
We comprehensively evaluated the patterns of Gln metabolism in 513 patients diagnosed with lung adenocarcinoma (LUAD) based on 73 Gln metabolism-related genes. Based on differentially expressed genes (DEGs), a risk model was constructed using Cox regression and Lasso regression analysis. The prognostic efficacy of the model was validated using an individual LUAD cohort form Shandong Provincial Hospital, an integrated LUAD cohort from GEO and pan-cancer cohorts from TCGA databases. Five independent immunotherapy cohorts were used to validate the model performance in predicting immunotherapy efficacy. Next, a series of single-cell sequencing analyses were used to characterize Gln metabolism in TME. Finally, single-cell sequencing analysis, transcriptome sequencing, and a series of
in vitro
experiments were used to explore the role of EPHB2 in LUAD.
Results
Patients with LUAD were eventually divided into low- and high-risk groups. Patients in low-risk group were characterized by low levels of Gln metabolism, survival advantage, “hot” immune phenotype and benefit from immunotherapy. Compared with other cells, tumor cells in TME exhibited the most active Gln metabolism. Among immune cells, tumor-infiltrating T cells exhibited the most active levels of Gln metabolism, especially CD8 T cell exhaustion and Treg suppression. EPHB2, a key gene in the model, was shown to promote LUAD cell proliferation, invasion and migration, and regulated the Gln metabolic pathway. Finally, we found that EPHB2 was highly expressed in macrophages, especially M2 macrophages. It may be involved in the M2 polarization of macrophages and mediate the negative regulation of M2 macrophages in NK cells.
Conclusion
This study revealed that the Gln metabolism-based model played a significant role in predicting prognosis and immunotherapy efficacy in lung cancer. We further characterized the Gln metabolism of TME and investigated the Gln metabolism-related gene EPHB2 to provide a theoretical framework for anti-tumor strategy targeting Gln metabolism.
Pyroptosis, defined as programmed cell death, results in the release of inflammatory mediators. Recent studies have revealed that pyroptosis plays essential roles in antitumor immunity and ...immunotherapy efficacy. Long noncoding RNAs (lncRNAs) are involved in a variety of biological behaviors in tumor cells, although the roles and mechanisms of lncRNAs in pyroptosis are rarely studied. Our study aimed to establish a novel pyroptosis-related lncRNA signature as a forecasting tool for predicting prognosis and ascertaining immune value. Based on lung adenocarcinoma (LUAD) patients from The Cancer Genome Atlas (TCGA), we performed Pearson’s correlation analysis to identify pyroptosis-related lncRNAs. After differentially expressed gene analysis and univariate Cox regression analysis, we selected prognosis-related and differentially expressed lncRNAs. Finally, we performed multivariate Cox regression analysis to establish the three pyroptosis-related lncRNA signature. Kaplan–Meier (KM) survival analyses and receiver operating characteristic (ROC) curves indicated the excellent performance for predicting the prognosis of LUAD patients. At the same time, we applied multidimensional approaches to further explore the functional enrichment, tumor microenvironment (TME) landscape, and immunotherapy efficacy among the different risk groups. A nomogram was constructed by integrating risk scores and clinical characteristics, which was validated using calibrations and ROC curves. Three lncRNAs, namely, AC090559.1, AC034102.8, and AC026355.2, were involved in this signature and used to classify LUAD patients into low- and high-risk groups. Overall survival time (OS) was higher in the low-risk group than in the high-risk group, which was also validated in our LUAD cohort from Shandong Provincial Hospital. TME landscape analyses revealed that a higher abundance of infiltrating immune cells and a greater prevalence of immune-related events existed in the low-risk group. Meanwhile, higher expression of immune checkpoint (ICP) genes, higher immunophenoscore (IPSs), and greater T cell dysfunction in the low-risk group demonstrated a better response to immunotherapy than the high-risk group. Combined with predictions from the Tumor Immune Dysfunction and Exclusion (TIDE) website, we found that LUAD patients in the low-risk group significantly benefited from programmed cell death 1 (PD-1) and cytotoxic T-lymphocyte–associated protein 4 (CTLA4) immune checkpoint blockade (ICB) therapy compared with those in the high-risk group. Furthermore, drug susceptibility analysis identified potential sensitive chemotherapeutic drugs for each risk group. In this study, a novel three pyroptosis-related lncRNA signature was constructed, which could accurately predict the immunotherapy efficacy and prognosis in LUAD patients.
Lung cancer remains the leading cause of cancer death globally. In 2015, the cancer classification guidelines of the World Health Organization were updated. The term "invasive mucinous adenocarcinoma ...(IMA)" aroused people's attention, while the clinicopathological factors that may influence survival were unclear.
Data of IMA patients was downloaded from SEER database. Kaplan-Meier methods and log-rank tests were used to compare the differences in OS and LCSS. The nomogram was developed based on the result of the multivariable analysis. The discrimination and accuracy were tested by Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analyses (DCA). Integrated discrimination improvement (IDI) index was used to evaluate the clinical efficacy.
According to multivariate analysis, the prognosis of IMAs was associated with age, differentiation grade, TNM stage and treatments. Surgery might be the only way that would improve survival. Area under the curve (AUC) of the training cohort was 0.834and 0.830 for3-and 5-year OS, respectively. AUC for 3-and 5-year LCSS were separately 0.839 and 0.839. The new model was then evaluated by calibration curve, DCA and IDI index.
Based on this study, prognosis of IMAs was systematically reviewed, and a new nomogram was developed and validated. This model helps us understand IMA in depth and provides new ideas for IMA treatment.
•A molecular-level model for delayed coking process was established.•The conversion behavior of sulfur in delayed coking process was investigated.•The sulfur compounds in gasoline were expressed as ...57 structural vectors.•The sulfur compounds were classified according to the discriminant rules.
In order to describe the reaction network and investigate the conversion behavior of sulfur compounds in delayed coking process, a molecular-level reaction kinetic model was established with a reaction network consisting of 81,081 reactions based on the structure-oriented lumping method. A feed molecular matrix containing 2,944 structural vectors was constructed with 24 structural increments based on the characteristics of the vacuum residue molecular composition. The reliability of the model was verified by industrial data. Through the calculation of the SOL model, the sulfur compounds in gasoline were expressed as 57 structural vectors, which were divided into thiophenes, mercaptans and thioethers according to the discriminant rules. The conversion law of sulfur compounds was investigated by tracking the reaction path of molecules in the reaction network. The SOL model could calculate the distribution of sulfur compounds in coking gasoline. The contents of thiophene molecules increased with the carbon numbers. Ethyl mercaptan and propyl mercaptan had higher content in mercaptans. The SOL model can reveal the influences of reaction conditions on sulfur compounds conversion in delayed coking process at the molecular level, which contributes to the accurate control of sulfur content in coking gasoline.
•FCC gasoline was upgraded on both octane number and olefin content by adsorption.•Adsorption energies explained the adsorbabilities of n-hydrocarbons from breakthrough curves.•Desorption oil showed ...excellent performance for producing ethylene in a cracker.
The octane number and the olefin content are two crucial indices for FCC gasoline. FCC gasoline was upgraded by a separation process that was superior to chemical processes including hydrogenation. The adsorption separation of normal paraffins and normal olefins in FCC gasoline was performed in a fixed-bed adsorber packed with 5A zeolites. The content of low octane normal paraffins decreased from 5wt% to less than 0.1wt% by the shape-selective separation of zeolites, leading to an increase in research octane number from 88.9 to 92.3. The olefin content decreased from 35.23wt% to 29.02wt% due to the removal of normal olefins. The adsorbabilities observed from the breakthrough curves of normal paraffins and normal olefins were consistent with the adsorption energies. The desorption oil, which was rich in normal hydrocarbons, showed excellent cracking performance for producing ethylene in a steam cracker.
Survival outcomes of patients with resected SCLC differ widely. The aim of our study was to build a model for individualized risk assessment and accurate prediction of overall survival (OS) in ...resectable SCLC patients.
We collected 1052 patients with resected SCLC from the Surveillance, Epidemiology, and End Results (SEER) database. Independent prognostic factors were selected by COX regression analyses, based on which a nomogram was constructed by R code. External validation were performed in 114 patients from Shandong Provincial Hospital. We conducted comparison between the new model and the AJCC staging system. Kaplan-Meier survival analyses were applied to test the application of the risk stratification system.
Sex, age, T stage, N stage, LNR, surgery and chemotherapy were identified to be independent predictors of OS, according which a nomogram was built. Concordance index (C-index) of the training cohort were 0.721, 0.708, 0.726 for 1-, 3- and 5-year OS, respectively. And that in the validation cohort were 0.819, 0.656, 0.708, respectively. Calibration curves also showed great prediction accuracy. In comparison with 8th AJCC staging system, improved net benefits in decision curve analyses (DCA) and evaluated integrated discrimination improvement (IDI) were obtained. The risk stratification system can significantly distinguish the ones with different survival risk. We implemented the nomogram in a user-friendly webserver.
We built a novel nomogram and risk stratification system integrating clinicopathological characteristics and surgical procedure for resectable SCLC. The model showed superior prediction ability for resectable SCLC.
Superhydrophobic substrate modifications are an effective way to improve SERS sensitivity by concentrating analyte molecules into a small surface area. However, it is difficult to manipulate ...low-volume liquid droplets on superhydrophobic substrates. To overcome this limitation, we deposited a hydrophilic Ti.sub.3C.sub.2T.sub.x film on a superhydrophobic ZnO nanorod array to create a SERS substrate with improved analyte affinity. Combined with its interfacial charge transfer properties, this enabled a rhodamine 6G detection limit of 10.sup.-11 M to be achieved. In addition, the new SERS substrate showed potential for detection of biological macromolecules, such as microRNA. Combined with its facile preparation, the SERS activity of ZnO/Ti.sub.3C.sub.2T.sub.x suggests it may provide an ultrasensitive environmental pollutant-monitoring and effective substrate for biological analyte detection.
Li-rich layer-structured cathode thin films are prepared by pulsed laser deposition. X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), X-ray photoelectron spectroscopy ...(XPS) and electrochemical testing in half battery cells are used to characterize crystal structure, surface morphology, chemical valence states and electrochemical performance of these thin films, respectively. It is observed that partial layer to spinel transformation takes place during post annealing, and the layered structure further gradually transforms to spinel during electrochemical cycling based on the analysis of dQ/dV. Electrochemical measurement shows that the thin film electrode deposited at 350 mTorr and post-annealed at 800 °C possesses the best performance.
The diffusion coefficient of C3–C8 normal paraffins in 5A zeolite channels from the simulation ranged from 4.22 × 10−10 cm2/s to 4.68 × 10−14 cm2/s, indicating a slow mass transfer process. In ...addition, the diffusion rate becomes apparently slower with the increasing carbon numbers of the examined paraffins. In order to improve the adsorption separation efficiency of for n-paraffins, 5A zeolites with mesoporous structures were synthesized by hydrothermal method with the dimethyl octadecyl 3-(trimethoxysilyl)propyl ammonium chloride as the template agent. Porosity and pore size distribution analysis demonstrated that micropores with the diameter of 0.5 nm were connected with 7–13 nm mesopores in the synthesized samples. The formation of hierarchical pore structure and change of surface morphology of zeolite particles could be controlled by the concentration of 3-(trimethoxysilyl)propyl ammonium chloride used in the synthesis. The normal paraffin/cyclohexane solutions were used to investigate the adsorption kinetics of pentane, hexane, and heptane on the synthesized 5A zeolites. When the 3-(trimethoxysilyl)propyl ammonium chloride concentration is 0.01%, the liquid phase diffusion coefficients of n-paraffins in the hierarchical 5A zeolite are 4–48 times larger than those in the microporous 5A zeolite. Our work demonstrates that the diffusion behavior and adsorption kinetics could be greatly improved by introducing mesoporosity into the pore structure of 5A zeolites.
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