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Background: The use of immune checkpoint inhibitors (ICIs) has become the standard of care for non-small cell lung cancer. The purpose of this study was to systematically review the literature to determine whether the occurrence of immune-related adverse events (irAEs) following the use of ICIs predicts different clinical outcomes in non-small cell lung cancer (NSCLC). Methods: Relevant studies from the time of database creation to July 20, 2023, were systematically searched to explore the differences in clinical outcomes in patients with advanced NSCLC with or without irAEs. The outcome indicators included the occurrence of irAEs, progression-free survival (PFS), and overall survival (OS). Results: 25 studies met the inclusion criteria. Of these studies, 22 reported the effect on OS, and 19 reported the effect on PFS. The results showed that for patients with NSCLC, the occurrence of irAEs after receiving immunotherapy showed a statistically significant benefit over the absence of irAEs for OS (HR=0.55,95% CI=0.46-0.65) and PFS (HR=0.55 95% CI=0.48-0.64), but severe irAEs (grades 3-5) were associated with worse OS (HR=1.05, 95% CI=0.87-1.27). Compared with gastrointestinal, lung, and hepatitis, irAEs of the skin and endocrine system tend to predict better OS and PFS. Conclusion: The occurrence of irAEs, especially mild and early irAEs, indicates better OS and PFS in patients with NSCLC treated with ICIs, irrespective of patient characteristics, type of ICIs, and irAEs. However, Grade 3 or higher toxicities resulted in worse OS. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023409444.
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Structurally complex corn bran arabinoxylan (CAX) was used as a model glycan to investigate gut bacteria growth and competition on different AX-based fine structures. Nine hydrolyzate segments of the CAX polymer varying in chemical structure (sugars and linkages), CAX, five less complex non-corn arabinoxylans, and xylose and glucose were ranked from structurally complex to simple. The substrate panel promoted different overall growth and rates of growth of eight Bacteroides xylan-degrading strains. For example, Bacteroides cellulosilyticus DSM 14838 (Bacteroides cellulosilyticus) grew well on an array of complex and simple structures, while Bacteroides ovatus 3-1-23 grew well only on the simple structures. In a competition experiment, B. cellulosilyticus growth was favored over B. ovatus on the complex AX-based structure. On the other hand, on the simple structure, B. ovatus strongly outcompeted B. cellulosilyticus, which was eliminated from the competitive environment by Day 11. This adaptation to fine structure and resulting competition dynamics indicate that dietary fiber chemical structures, whether complex or simple, favor certain gut bacteria. Overall, this work supports a concept that fiber degraders diversify their competitive abilities to access substrates across the spectrum of heterogeneity of fine structural features of dietary fibers.
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Improving the N2 selectivity is always a great challenge for the selective catalytic oxidation of ammonia (NH3-SCO) over noble-metal-based (especially Pt) catalysts. In this work, Cu as an efficient promoter was introduced into the Pt/SSZ-13 catalyst to significantly improve the N2 selectivity of the NH3-SCO reaction. A PtCu alloy was formed in the PtCu/SSZ-13 catalyst, as confirmed by X-ray diffraction, transmission electron microscopy, energy dispersive spectrometry mapping, and X-ray absorption spectroscopy results. As indicated by the X-ray photoelectron spectroscopy analysis, the Pt species in the alloyed PtCu nanoparticle was mainly present in the electron-rich state on PtCu/SSZ-13, while the electron-deficient Cu and isolated Cu2+ species were both present on the surface of PtCu/SSZ-13. Due to such a unique alloyed structure with an altered oxidation state, the N2 selectivity of NH3-SCO on the PtCu/SSZ-13 catalyst was remarkably improved, while the NH3-SCO activity was kept comparable to that on Pt/SSZ-13. The reaction path was changed from the NH mechanism on Pt/SSZ-13 to both NH and internal selective catalytic reduction mechanisms on the PtCu/SSZ-13 catalyst, which was considered the main reason for the enhanced N2 selectivity. This work provides a new route to synthesize efficient alloy catalysts for optimizing the N2 selectivity of NH3-SCO for NH3 slip control in diesel exhaust purification.
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Selective catalytic reduction of NOx by NH3 (NH3-SCR) for diesel emission control at low temperatures is still a great challenge due to the limit of the urea injection threshold and inferior SCR activity of state-of-the-art catalyst systems below 200 °C. Fabricating bifunctional catalysts with both low temperature NOx adsorption-storage capacity and medium-high temperature NOx reduction activity is an effective strategy to solve the issues mentioned above but is rarely investigated. Herein, the WO3/Ce0.68Zr0.32Ox (W/CZ) catalyst containing the κ-Ce2Zr2O8 pyrochlore structure was successfully developed by a simple H2 reduction method, not only showing superior NOx adsorption-storage ability below 180 °C but also exhibiting excellent NH3-SCR activity above 180 °C. The presence of the pyrochlore structure effectively increased the oxygen vacancies on the κ-Ce2Zr2O8-containing W/CZ catalyst with enhanced redox property, which significantly promoted the NOx adsorption-storage as active nitrate species below 180 °C. Upon NH3 introduction above 180 °C, the κ-Ce2Zr2O8-containing W/CZ catalyst showed greatly improved NOx reduction performance, suggesting that the pyrochlore structure played a vital role in improving the NOx adsorption-selective catalytic reduction (AdSCR) performance. This work provides a new perspective for designing bifunctional CeZrOx-based catalysts to efficiently control the NOx emissions from diesel engines during the cold-start process.
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Amônia , Nióbio , Adsorção , Amônia/química , Oxirredução , CatáliseRESUMO
Supported palladium (Pd) catalysts are widely utilized to reduce the emission of exhaust CH4 from lean-burn engines by catalytic combustion. A large amount of water vapor in the exhaust makes hydroxyls accumulate on the catalyst surface at temperatures below 450 °C, leading to severe catalyst deactivation. Tuning palladium chemistry and inhibiting water adsorption are critical to developing active catalysts. Modifying the support surface with inert silicates would both change the palladium-support interaction and decrease water adsorption sites. This study reports an improved Pd/Y2O3-ZrO2 catalyst by constructing silicate patches on yttria-stabilized zirconia (Y2O3-ZrO2) support. The silicates hindered electron transfer from Y2O3-ZrO2 oxygen vacancies to palladium, which optimized palladium chemistry, especially the reducibility of active PdO species, and thereby boosted CH4 conversion under dry conditions. The temperature of 90% methane conversion (T90) over the catalyst decreased from 386 to 309 °C. Moreover, the inert silicates decreased surface oxygen vacancies of Y2O3-ZrO2 to improve support hydrophobicity, thereby inhibiting hydroxyl accumulation. The poisoning effect of water on the active sites located on the palladium-silicate interface was alleviated. When reaction gases contained 10 vol % water, the silicate-modified catalyst still showed higher activity with T90 of 404 °C, which is lower than T90 of 452 °C for unmodified catalyst. This work represents a step forward in preparing high-performance palladium catalysts for low-temperature wet methane combustion.
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Background: The neoadjuvant use of immune checkpoint inhibitor combined with chemotherapy (nICT) or chemoradiotherapy (nICRT) in locally advanced esophageal cancer (EC) is currently an area of active ongoing research. Therefore, we carried out a comprehensive meta-analysis to compare the efficacy and safety of the new strategy with routine neoadjuvant strategy, which included neoadjuvant chemotherapy (nCT) and neoadjuvant chemoradiotherapy (nCRT). Patients and methods: MEDLINE (via PubMed), Embase (via OVID), ISI Web of Science database and Cochrane Library were included. And, all of them were searched for eligible studies between January, 2000 and February, 2023. The pathological complete response (pCR) and major pathological response (MPR) were primary outcome of our study. The second outcome of interest was R0 resection rate. Odds ratio (OR) and associated 95% CI were used as the effect indicators comparing the safety and efficiency of the neoadjuvant immunotherapy with the routine neoadjuvant therapy. Fixed-effect model (Inverse Variance) or random-effect model (Mantel-Haenszel method) was performed depending on the statistically heterogeneity. Results: There were eight trials with 652 patients were included in our meta-analysis. The estimated pCR rate was higher in the neoadjuvant immunotherapy group (OR =1.86; 95% CI, 1.25-2.75; I2 = 32.8%, P=0.166). The different results were found in the esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) subgroups, the estimated OR was 2.35 (95%CI, 1.00-2.72; I2 = 30.9%, P=0.215) in the EAC subgroup, and 2.35 (95% CI, 1.20-4.54; I2 = 45.3%, P=0.161) in the ESCC subgroup, respectively. The neoadjuvant immunotherapy also showed the advantage in the MPR rates (OR =2.66; 95% CI, 1.69-4.19; I2 = 24.3%, P=0.252). There was no obvious difference between the neoadjuvant immunotherapy and routine neoadjuvant therapy with respect to surgical resection rate, R0 resection rate, surgical delay rate; while more treatment-related adverse events were observed for the neoadjuvant immunotherapy for pneumonitis/pneumonia (OR=3.46, 95% CI, 1.31-9.16; I2 = 67.3%, P=0.005) and thyroid dysfunction (OR=4.69, 95% CI, 1.53-14.36; I2 = 56.5%, P=0.032). Conclusion: The pooled correlations indicated that the neoadjuvant immunotherapy (both nICT and nICRT) could significantly increase the rates of pCR and MPR, compared with routine neoadjuvant therapy (both nCT and nCRT) in the treatment of locally advanced EC. The neoadjuvant immunotherapy and routine neoadjuvant therapy were with acceptable toxicity. However, randomized studies with larger groups of patients need to performed to confirm these results. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42020155802.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patologia , Terapia Neoadjuvante/métodos , Carcinoma de Células Escamosas do Esôfago/terapia , Imunoterapia/efeitos adversosRESUMO
Corn arabinoxylan (CAX), a cell wall-derived dietary fiber, was extracted with alkali, partially purified, and treated with hydrolytic enzymes in order to investigate the relationship of fine structure and fermentability by the human gut microbiota. Glycosyl composition and linkage analysis of CAX and two hydrolysates, coupled with molecular size analysis, indicated an organized structural feature of the native polymer, which consists of a repeating structural subunit containing complex branching patterns along the xylan backbone and flanked by regions of less complexity. The two lengths of the highly branched subunit were isolated and were shown to have enhanced slow fermentation property compared to the native structure (3.3 vs. 5.9 mL gas, 4 h), that was related to increasing complexity of the branched structures. Lower molecular size structures with higher branch complexity fermented slower, contrary to a conventional view that small fiber structures approaching the oligosaccharide level are necessarily more rapidly fermented.
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Microbioma Gastrointestinal , Xilanos , Fibras na Dieta/análise , Fermentação , Humanos , Xilanos/química , Zea mays/químicaRESUMO
There are two most widely used transthoracic esophagectomy methods: the McKeown Minimally Invasive esophagectomy (McKeown MIE) and the Sweet Esophagectomy. We evaluated and compared the therapeutic effects of these two methods to determine the appropriate method for the treatment of middle and lower third esophageal cancer patients who received neoadjuvant chemotherapy combined with immunotherapy (NACI). We retrospectively analyzed 43 sweet esophagectomy cases received NACI and 167 cases with McKeown MIE in the fourth hospital of Hebei Medical University from December 2019 to May 2022. This retrospective observational study showed that Sweet esophagectomy and McKeown MIE after NACI therapy for resectable ESCC patients appeared to be safe with low operative mortality and morbidity rate in the current population. In addition, sweet esophagectomy was associated with a lower incidence of severe complications and shorter hospital stay for patients over 70 years of age compared with McKeown MIE. There were no differences were found in length of stay, mortality and complication incidence rate between the two groups. The Sweet approach has advantage in hospital stay for the treatment of the elderly NACI patients with middle or lower third esophageal squamous cell carcinoma. In conclusion, Sweet esophagectomy and McKeown MIE are both safe, effective, and worthwhile approaches for ESCC patients in immunotherapy age.
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BACKGROUND: At present, the clinical conclusion that robotic-assisted thoracic surgery (RATS) and video-assisted thoracic surgery (VATS), which is better for patients with non-small cell lung cancer (NSCLC) is not clear. Therefore, this meta-analysis aimed to compare the perioperative outcomes between RATS and VATS for NSCLC. METHODS: The Population, Interventions, Comparators, Outcomes, and Study design (PICOS) framework was employed to develop the search strategy, and the findings was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched EMbase, The Cochrane Library, PubMed, Web of Science, CNKI, and Wan Fang Data to collect clinical studies about RATS vs. VATS for patients with NSCLC from inception to October 2019. The following outcomes were measured: rate of conversion to thoracotomy, postoperative complications, postoperative hospital mortality, lymph node dissection, hospitalization time, operating time, and postoperative drainage days. Estimation of potential publication bias was conducted by Begg's test and Egger's test. The Standardized Mean Difference (SMD) and Odds Ratio (OR) with 95% confidence intervals (CI) were pooled using Stata 15.0 software. RESULTS: A total of 18 studies involving 60,349 patients were included. Among them, 8,726 cases were in the RATS group, and 51,623 were in the VATS group. The results of meta-analysis showed that the operation time of RATS group was longer than that of VATS group (SMD=0.532, 95% CI: 0.391-0.674, P=0.000). And the further meta-analysis suggested that the incidence of postoperative complications was lower in patients who underwent RATS after 2015 (OR=0.848, 95% CI: 0.748-0.962, P=0.010). Meanwhile, there was no significant difference between both groups in postoperative hospitalization time (SMD=0.003, 95% CI: -0.104-0.110, P=0.957). In addition, more lymph nodes were retrieved in RATS group than VATS (SMD=0.308, 95% CI: 0.131-0.486, P=0.001). However, the conversion rate, retrieved lymph node station, days to tube removal and in-hospital mortality rate have no significant differences between both groups. DISCUSSION: The current meta-analysis indicates that the perioperative outcomes of RATS and VATS for NSCLC are equivalence. Due to the limited quantity and quality of included studies, the above conclusions still need to be verified by more high-quality studies.
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Strong metal-support interaction (SMSI) is recognized as a pivotal strategy in hetereogeneous catalysis to prevent the sintering of metal nanoparticles (NPs), but issues including restriction of supports to reducible metal oxides, nonporous architecture, sintering by thermal treatment at >800 °C, and unstable nature limit their practical application. Herein, the construction of non-oxide-derived SMSI nanocatalysts based on highly crystalline and nanoporous hexagonal boron nitride (h-BN) 2D materials was demonstrated via in situ encapsulation and reduction using NaBH4, NaNH2, and noble metal salts as precursors. The as-prepared nanocatalysts exhibited robust thermal stability and sintering resistance to withstand thermal treatment at up to 950 °C, rendering them with high catalytic efficiency and durability in CO oxidation even in the presence of H2O and hydrocarbon simulated to realistic exhaust systems. More importantly, our generic strategy offers a novel and efficient avenue to design ultrastable hetereogeneous catalysts with diverse metal and support compositions and architectures.
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Single-atom catalysts (SACs) have attracted considerable attention in the catalysis community. However, fabricating intrinsically stable SACs on traditional supports (N-doped carbon, metal oxides, etc.) remains a formidable challenge, especially under high-temperature conditions. Here, we report a novel entropy-driven strategy to stabilize Pd single-atom on the high-entropy fluorite oxides (CeZrHfTiLa)Ox (HEFO) as the support by a combination of mechanical milling with calcination at 900 °C. Characterization results reveal that single Pd atoms are incorporated into HEFO (Pd1@HEFO) sublattice by forming stable Pd-O-M bonds (M = Ce/Zr/La). Compared to the traditional support stabilized catalysts such as Pd@CeO2, Pd1@HEFO affords the improved reducibility of lattice oxygen and the existence of stable Pd-O-M species, thus exhibiting not only higher low-temperature CO oxidation activity but also outstanding resistance to thermal and hydrothermal degradation. This work therefore exemplifies the superiority of high-entropy materials for the preparation of SACs.
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NH3 emissions were limited strictly because of the threat for human health and sustainable development. Pt/Al2O3 and Pt/CeZrO2 were prepared by the impregnation method. Differences in surface chemical states, reduction ability, acid properties, morphological properties, reaction mechanisms, and ammonia oxidation activity were studied. It indicated that Pt species states were affected by different metal-support interactions. The homogeneously dispersed Pt species over Pt/Al2O3 exposed Pt(111) because of weak metal-support interactions; there even existed an obvious interface between Pt and Al2O3. While obscure even an overlapped interface was observed over Pt/CeZrO2, resulting in the formation of PtO because of the oxygen migration from CeZrO2 to Pt species (confirmed by CO-FTIR, the cycled H2-TPR and transmission electron microscopy results). It was noteworthy that different reaction mechanisms were induced by different states of Pt species; NH was the key intermediate species for ammonia oxidation reaction over Pt/Al2O3, but two kinds of intermediates, N2H4 and HNO, were observed for Pt/CeZrO2. It consequently resulted in the obvious distinction of the NH3-SCO catalytic performance; the light-off temperatures of NH3 over Pt/Al2O3 and Pt/CeZrO2 were 231 and 275 °C, respectively, while the maximum N2 selectivity (65%) was obtained over Pt/CeZrO2, it was obviously better than that over Pt/Al2O3.
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Amônia/química , Catálise , Platina/química , Zircônio/química , Óxido de Alumínio/química , Microscopia Eletrônica de Transmissão , Oxirredução , Oxigênio/químicaRESUMO
As a promising candidate for NOx elimination from the emission of diesel engines, the enhancement effect of Ba on the hydrothermal stability of cordierite supported CuBa/BEA at 600 °C for 48 h was investigated by XRD, NH3-TPD, H2-TPR, XPS, EPR, TEM and in situ DRIFTS. Different properties and amounts of active species are significant factors contributing to the enhanced hydrothermal stability of CuBa/BEA-HT. CuBa/BEA-HT has more Cu2+/Cu+ redox-couples and stronger interactions than Cu/BEA-HT, indicating an excellent redox property of the active species in CuBa/BEA-HT. The better redox property of CuBa/BEA-HT produces more nitrates that easily participate in the NH3-SCR reaction, which enhances the low-temperature activity. Furthermore, as observed from EPR and H2-TPR, the appearance of more isolated Cu2+ species and fewer CuO species also contribute to the higher hydrothermal stability of CuBa/BEA-HT.