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Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that CâC bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.
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The asymmetric total synthesis of pedrolide (>200 mg) with an unprecedented [5-5-5-6-6-3] hexacyclic core (pedrolane) was achieved. Its unique bicyclo[2.2.1]heptane ring system was efficiently constructed via an enantioselective ene reaction of cyclopentadiene followed by a Wittig reaction, isomerization, and a diastereoselective intramolecular Diels-Alder reaction cascade. The highly oxygenated carane [6-3] ring system was synthesized via a ring-closing metathesis reaction followed by an unusual free carbene cyclopropanation. Furthermore, the 12 contiguous stereocenters of pedrolide were installed diastereoselectively.
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Scarce and expensive iridium oxide is still the cornerstone catalyst of polymer-electrolyte membrane electrolyzers for green hydrogen production because of its exceptional stability under industrially relevant oxygen evolution reaction (OER) conditions. Earth-abundant transition metal oxides used for this task, however, show poor long-term stability. We demonstrate here the use of nitrogen-doped cobalt oxide as an effective iridium substitute. The catalyst exhibits a low overpotential of 240 mV at 10 mA cm-2 and negligible activity decay after 1000 h of operation in an alkaline electrolyte. Incorporation of nitrogen dopants not only triggers the OER mechanism switched from the traditional adsorbate evolution route to the lattice oxygen oxidation route but also achieves oxygen nonbonding (ONB) states as electron donors, thereby preventing structural destabilization. In a practical anion-exchange membrane water electrolyzer, this catalyst at anode delivers a current density of 1000 mA cm-2 at 1.78 V and an electrical efficiency of 47.8 kW-hours per kilogram hydrogen.
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BACKGROUND: Gastric cancer (GC) is the fifth most common and the fourth most lethal malignant tumour in the world. Most patients are already in the advanced stage when they are diagnosed, which also leads to poor overall survival. The effect of postoperative adjuvant chemotherapy for advanced GC is unsatisfactory with a high rate of distant metastasis and local recurrence. AIM: To investigate the safety and efficacy of a programmed cell death 1 (PD-1) inhibitor combined with oxaliplatin and S-1 (SOX) in the treatment of Borrmann large type III and IV GCs. METHODS: A retrospective analysis (IRB-2022-371) was performed on 89 patients with Borrmann large type III and IV GCs who received neoadjuvant therapy (NAT) from January 2020 to December 2021. According to the different neoadjuvant treatment regimens, the patients were divided into the SOX group (61 patients) and the PD-1 + SOX (P-SOX) group (28 patients). RESULTS: The pathological response (tumor regression grade 0/1) in the P-SOX group was significantly higher than that in the SOX group (42.86% vs 18.03%, P = 0.013). The incidence of ypN0 in the P-SOX group was higher than that in the SOX group (39.29% vs 19.67%, P = 0.05). The use of PD-1 inhibitors was an independent factor affecting tumor regression grade. Meanwhile, the use of PD-1 did not increase postoperative complications or the adverse effects of NAT. CONCLUSION: A PD-1 inhibitor combined with SOX could significantly improve the rate of tumour regression during NAT for patients with Borrmann large type III and IV GCs.
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Objective: This study aimed to compare the current Essen rabies post-exposure immunization schedule (0-3-7-14-28) in China and the simple 4-dose schedule (0-3-7-14) newly recommended by the World Health Organization in terms of their safety, efficacy, and protection. Methods: Mice were vaccinated according to different immunization schedules, and blood was collected for detection of rabies virus neutralizing antibodies (RVNAs) on days 14, 21, 28, 35, and 120 after the first immunization. Additionally, different groups of mice were injected with lethal doses of the CVS-11 virus on day 0, subjected to different rabies immunization schedules, and assessed for morbidity and death status. In a clinical trial, 185 rabies-exposed individuals were selected for post-exposure vaccination according to the Essen schedule, and blood was collected for RVNAs detection on days 28 and 42 after the first immunization. Results: A statistically significant difference in RVNAs between mice in the Essen and 0-3-7-14 schedule groups was observed on the 35th day ( P < 0.05). The groups 0-3-7-14, 0-3-7-21, and 0-3-7-28 showed no statistically significant difference ( P > 0.05) in RVNAs levels at any time point. The post-exposure immune protective test showed that the survival rate of mice in the control group was 20%, whereas that in the immunization groups was 40%. In the clinical trial, the RVNAs positive conversion rates on days 28 (14 days after 4 doses) and 42 (14 days after 5 doses) were both 100%, and no significant difference in RVNAs levels was observed ( P > 0.05). Conclusion: The simple 4-dose schedule can produce sufficient RVNAs levels, with no significant effect of a delayed fourth vaccine dose (14-28 d) on the immunization potential.
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Vacina Antirrábica , Vírus da Raiva , Raiva , Animais , Camundongos , Raiva/prevenção & controle , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinação , China , Profilaxia Pós-ExposiçãoRESUMO
Background: Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) contribute to more than 95% of thyroid malignancies. However, synchronous PTC and FTC are less common; it is most commonly discovered incidentally as synchronous malignancies during operation, which adds difficulties to intraoperative decision-making and postoperative treatment. Therefore, we analyzed the clinicopathological characteristics and prognosis of patients with PTC and FTC in our center. Methods: We conducted a search of single PTC, single FTC, and synchronous PTC/FTC patients who received initial surgery treatment at Fudan University Shanghai Cancer Center from 2006 to 2018 and collected paraffin-embedded samples of synchronous patients. Clinicopathological characteristics were collected from the electronic medical record system. Follow-up was performed through telephone contact or medical records. Exome sequencing was performed by ThyroLead panel. Results: Total of 42 synchronous PTC/FTC patients, 244 single FTC patients, and 2,959 single PTC patients were included. It showed a similarity between the clinicopathological features of synchronous thyroid cancer patients and single PTC patients, with a greater proportion of females, higher probabilities of lymph node metastasis, and higher rate of concurrence of Hashimoto's disease. The disease-free survival (DFS) curve indicated a worse prognosis of the synchronous group and single PTC group compared to the single FTC group, who had a propensity for neck lymph node recurrence; however, logistic multivariate regression analysis did not find any factor related to recurrence in the synchronous group. After re-checking pathology, DNA extraction, and quality control, genetic alteration information of 62 samples including primary tumors and metastatic lymph nodes from 35 synchronous cancer patients was displayed. In total, 81 mutations and 1 fusion gene were identified, including mutations related to outcomes and targeted therapy. Besides, some rare mutations in thyroid cancer were found in these patients. Conclusions: To conclude, synchronous PTC/FTC tend to be incidentally discovered during or after operation, behaving more like single PTC. The prognosis of synchronous patients is worse than that of single FTC patients and supplemental cervical lymph node dissection, total thyroidectomy, and postoperative radioiodine therapy should be taken into consideration after diagnosis. The next-generation sequencing (NGS) showed a unique molecular feature of synchronous patients with some rare mutations.
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Both anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) originate from thyroid follicular epithelial cells, but ATC has a significantly worse prognosis and shows resistance to conventional therapies. However, clinical trials found that immunotherapy works better in ATC than late-stage PTC. Here, we used single-cell RNA sequencing (scRNA-Seq) to generate a single-cell atlas of thyroid cancer. Differences in ATC and PTC tumor microenvironment components (including malignant cells, stromal cells, and immune cells) leading to the polarized prognoses were identified. Intriguingly, we found that CXCL13+ T lymphocytes were enriched in ATC samples and might promote the development of early tertiary lymphoid structure (TLS). Last, murine experiments and scRNA-Seq analysis of a treated patient's tumor demonstrated that famitinib plus anti-PD-1 antibody could advance TLS in thyroid cancer. We displayed the cellular landscape of ATC and PTC, finding that CXCL13+ T cells and early TLS might make ATC more sensitive to immunotherapy.
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Quimiocina CXCL13 , Imunoterapia , Câncer Papilífero da Tireoide , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Microambiente Tumoral , Microambiente Tumoral/imunologia , Humanos , Carcinoma Anaplásico da Tireoide/patologia , Carcinoma Anaplásico da Tireoide/terapia , Carcinoma Anaplásico da Tireoide/imunologia , Animais , Camundongos , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/imunologia , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/terapia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/imunologia , Neoplasias da Glândula Tireoide/terapia , Neoplasias da Glândula Tireoide/genética , Imunoterapia/métodos , Quimiocina CXCL13/metabolismo , Quimiocina CXCL13/genética , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/patologia , Análise de Célula Única , Prognóstico , Linfócitos T/imunologia , Feminino , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , MasculinoRESUMO
A significant variation in chromatin accessibility is an epigenetic feature of leukemia. The cause of this variation in leukemia, however, remains elusive. Here, we identify SMARCA5, a core ATPase of the imitation switch (ISWI) chromatin remodeling complex, as being responsible for aberrant chromatin accessibility in leukemia cells. We find that SMARCA5 is required to maintain aberrant chromatin accessibility for leukemogenesis and then promotes transcriptional activation of AKR1B1, an aldo/keto reductase, by recruiting transcription co-activator DDX5 and transcription factor SP1. Higher levels of AKR1B1 are associated with a poor prognosis in leukemia patients and promote leukemogenesis by reprogramming fructose metabolism. Moreover, pharmacological inhibition of AKR1B1 has been shown to have significant therapeutic effects in leukemia mice and leukemia patient cells. Thus, our findings link the aberrant chromatin state mediated by SMARCA5 to AKR1B1-mediated endogenous fructose metabolism reprogramming and shed light on the essential role of AKR1B1 in leukemogenesis, which may provide therapeutic strategies for leukemia.