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1.
Biochem Biophys Res Commun ; 720: 150066, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-38749193

ABSTRACT

Alveolar and interstitial macrophages play crucial roles in eradicating pathogens and transformed cells in the lungs. The immune checkpoint CD47, found on normal and malignant cells, interacts with the SIRPα ligand on macrophages, inhibiting phagocytosis, antigen presentation, and promoting immune evasion. In this study, we demonstrated that CD47 is not only a transmembrane protein, but that it is also highly concentrated in extracellular vesicles from lung cancer cell lines and patient plasma. Abundant CD47 was observed in the cytoplasm of lung cancer cells, aligning with our finding that it was packed into extracellular vesicles for physiological and pathological functions. In our clinical cohort, extracellular vesicle CD47 was significantly higher in the patients with early-stage lung cancer, emphasizing innate immunity inactivation in early tumor progression. To validate our hypothesis, we established an orthotopic xenograft model mimicking lung cancer development, which showed increased serum soluble CD47 and elevated IL-10/TNF-α ratio, indicating an immune-suppressive tumor microenvironment. CD47 expression led to reduced tumor-infiltrating macrophages during progression, while there was a post-xenograft increase in tumor-associated macrophages. In conclusion, CD47 is pivotal in early lung cancer progression, with soluble CD47 emerging as a key pathological effector.


Subject(s)
CD47 Antigen , Disease Progression , Lung Neoplasms , CD47 Antigen/metabolism , CD47 Antigen/immunology , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Humans , Animals , Cell Line, Tumor , Extracellular Vesicles/immunology , Extracellular Vesicles/metabolism , Mice , Tumor Escape , Immune Evasion , Tumor Microenvironment/immunology , Macrophages/immunology , Macrophages/metabolism , Female , Neoplasm Staging
2.
J Oncol Pharm Pract ; 29(6): 1374-1380, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36112905

ABSTRACT

BACKGROUND: Painful paronychia and pseudopyogenic granuloma (PG) are common adverse drug reactions (ADRs) associated with the use of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) to treat non-small cell lung cancer (NSCLC). Multiple local management approaches have been tested with unsatisfactory results. We have introduced an occlusion therapy technique through which available topical drugs for longer than 2 years. METHODS: Based on the cancer registry and case management system of our hospital, from July 2019 to July 2020, we retrospectively enrolled patients with NSCLC who were treated with EGFR-TKIs and received applications of 0.5% timolol ophthalmic solution (TIMOPTOL XE 0.5%®) combined with a neomycin/tyrothricin ointment (Biomycin®) using the occlusion method to treat paronychia or PG. RESULTS: A total of 22 patients were enrolled, with a mean age of 66.5 years, most of whom were women (72.7%). Periungual lesion-related pain was reported by all patients, and periungual bleeding and PG were reported in 14% (3/22) and 64% (14/22) of patients, respectively. After the occlusion therapy application of timolol ophthalmic solution combined with neomycin/tyrothricin ointment twice daily, the overall response rate was 83.3%, including complete response in 18% (4/22) of cases and partial response in 68% (15/22) of cases. CONCLUSION: We presented an occlusion method using available topical beta-blockers and antibiotic ointment for EGFR-TKI-induced paronychia and PG in Taiwan. The result is favorable. Further randomized control trial is urgent to validate our findings.


Subject(s)
Angiolymphoid Hyperplasia with Eosinophilia , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Paronychia , Humans , Female , Aged , Male , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Timolol/adverse effects , Angiolymphoid Hyperplasia with Eosinophilia/chemically induced , Angiolymphoid Hyperplasia with Eosinophilia/drug therapy , Retrospective Studies , Anti-Bacterial Agents/adverse effects , Paronychia/chemically induced , Paronychia/drug therapy , Ointments/adverse effects , Taiwan , Protein Kinase Inhibitors/adverse effects , Neomycin/adverse effects , ErbB Receptors , Tyrothricin/adverse effects , Ophthalmic Solutions/adverse effects , Mutation
3.
J Formos Med Assoc ; 122(10): 1061-1068, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37105870

ABSTRACT

BACKGROUND/PURPOSE: Pulmonary alveolar proteinosis (PAP) is rare disease manifested as alveolar macrophage dysfunction and abnormal accumulation of surfactant protein in the alveoli. In this nationwide, population-based study, we investigated the epidemiology of PAP in Taiwan, and discovered the comorbidities and prognostic factors of PAP. METHODS: From the National Health Insurance Research Database (NHIRD), we obtained comprehensive information about all patients of PAP in Taiwan between 1995 and 2013. The incidence, baseline characteristics comorbidities, and prognostic factors of PAP were investigated. RESULTS: The annual incidence rate of PAP was around 0.79 (range: 0.49-1.17) patients per million people after 2000, and the prevalence rate was 7.96 patients per million people by the end of 2013. In total, 276 patients of PAP were identified, including 177 (64%) and 99 (36%) patients with primary and secondary PAP, respectively. The median age of diagnosis was 53.8 years. The median survival was 9.6 years after the initial PAP diagnosis, and the 5-year survival rate was 65.96%. Twenty (7%) patients received whole lung lavage (WLL) within three months after the diagnosis had significantly better survival compared to the others. Multivariable Cox regression analyses showed that elder age, secondary PAP, and malignancy were associated with poorer survival, while WLL within 3 months of diagnosis might greatly improve the survival. CONCLUSION: We demonstrated the epidemiology of PAP in Taiwan, showing several poor prognostic factors and the potential effectiveness of WLL. Further prospective studies based on registry are warranted to improve the diagnosis and treatment of PAP.


Subject(s)
Pulmonary Alveolar Proteinosis , Humans , Aged , Middle Aged , Infant , Pulmonary Alveolar Proteinosis/epidemiology , Pulmonary Alveolar Proteinosis/therapy , Pulmonary Alveolar Proteinosis/diagnosis , Taiwan/epidemiology , Prospective Studies , Bronchoalveolar Lavage , Lung/pathology
4.
Small ; 18(18): e2200395, 2022 05.
Article in English | MEDLINE | ID: mdl-35384295

ABSTRACT

Carbon-based single metal atom catalysts (SACs) are being extensively investigated to improve the kinetics of the Li-S redox reaction, which is greatly important for batteries with cell-level energy densities >500 W h kg-1 . However, there are contradictory reports regarding the electrocatalytic activities of the different metal atoms and the role of the metal atom in LiS chemistry still remains unclear. This is due to the complex relationship between the catalytic behavior and the structure of carbon-based SACs. Here, the catalytic behavior and active-site geometry, oxidation state, and the electronic structure of different metal centers (Fe/Co/Ni) embedded in nitrogen-doped graphene, and having similar physicochemical characteristics, are studied. Combining X-ray absorption spectroscopy, density functional theory calculations, and electrochemical analysis, it is revealed that the coordination-geometry and oxidation state of the metal atoms are modified when interacting with sulfur species. This interaction is strongly dependent on the hybridization of metal 3d and S p-orbitals. A moderate hybridization with the Fermi level crossing the metal 3d band is more favorable for LiS redox reactions. This study thus provides a fundamental understanding of how metal atoms in SACs impact LiS redox behavior and offers new guidelines to develop highly active catalytic materials for high-performance LiS batteries.


Subject(s)
Carbon , Metals , Carbon/chemistry , Catalysis , Metals/chemistry , Nitrogen/chemistry , Oxidation-Reduction
5.
Faraday Discuss ; 236(0): 103-125, 2022 Aug 25.
Article in English | MEDLINE | ID: mdl-35485389

ABSTRACT

Photoelectron spectroscopy offers detailed information about the electronic structure and chemical composition of surfaces, owing to the short distance that the photoelectrons can escape from a dense medium. Unfortunately, photoelectron based spectroscopies are not directly compatible with the liquids required to investigate electrochemical processes, especially in the soft X-ray regime. To overcome this issue, different approaches based on photoelectron spectroscopy have been developed in our group over the last few years. The performance and the degree of information provided by these approaches are compared with those of the well established bulk sensitive spectroscopic approach of total fluorescence yield detection, where the surface information gained from this approach is enhanced using samples with large surface to bulk ratios. The operation of these approaches is exemplified and compared using the oxygen evolution reaction on IrOx catalysts. We found that all the approaches, if properly applied, provide similar information about surface oxygen speciation. However, using resonant photoemission spectroscopy, we were able to prove that speciation is more involved and complex than previously thought during the oxygen evolution reaction on IrOx based electrocatalysts. We found that the electrified solid-liquid interface is composed of different oxygen species, where the terminal oxygen atoms on iridium are the active species, yielding the formation of peroxo species and, finally, dioxygen as the reaction product. Thus, the oxygen-oxygen bond formation is dominated by peroxo species formation along the reaction pathway. Furthermore, the methodologies discussed here open up opportunities to investigate electrified solid-liquid interfaces in a multitude of electrochemical processes with unprecedented speciation capabilities, which are not accessible by one-dimensional X-ray spectroscopies.

6.
Int J Mol Sci ; 23(3)2022 Feb 02.
Article in English | MEDLINE | ID: mdl-35163650

ABSTRACT

Focal adhesion kinase (FAK), a non-receptor tyrosine kinase, is overexpressed and activated in many cancer types. FAK regulates diverse cellular processes, including growth factor signaling, cell cycle progression, cell survival, cell motility, angiogenesis, and the establishment of immunosuppressive tumor microenvironments through kinase-dependent and kinase-independent scaffolding functions in the cytoplasm and nucleus. Mounting evidence has indicated that targeting FAK, either alone or in combination with other agents, may represent a promising therapeutic strategy for various cancers. In this review, we summarize the mechanisms underlying FAK-mediated signaling networks during tumor development. We also summarize the recent progress of FAK-targeted small-molecule compounds for anticancer activity from preclinical and clinical evidence.


Subject(s)
Focal Adhesion Kinase 1/physiology , Neoplasms , Animals , Antineoplastic Agents/pharmacology , Humans , Neoplasms/metabolism , Neoplasms/therapy , Tumor Microenvironment
7.
J Am Chem Soc ; 143(32): 12524-12534, 2021 Aug 18.
Article in English | MEDLINE | ID: mdl-34355571

ABSTRACT

Iridium and ruthenium and their oxides/hydroxides are the best candidates for the oxygen evolution reaction under harsh acidic conditions owing to the low overpotentials observed for Ru- and Ir-based anodes and the high corrosion resistance of Ir-oxides. Herein, by means of cutting edge operando surface and bulk sensitive X-ray spectroscopy techniques, specifically designed electrode nanofabrication and ab initio DFT calculations, we were able to reveal the electronic structure of the active IrOx centers (i.e., oxidation state) during electrocatalytic oxidation of water in the surface and bulk of high-performance Ir-based catalysts. We found the oxygen evolution reaction is controlled by the formation of empty Ir 5d states in the surface ascribed to the formation of formally IrV species leading to the appearance of electron-deficient oxygen species bound to single iridium atoms (µ1-O and µ1-OH) that are responsible for water activation and oxidation. Oxygen bound to three iridium centers (µ3-O) remains the dominant species in the bulk but do not participate directly in the electrocatalytic reaction, suggesting bulk oxidation is limited. In addition a high coverage of a µ1-OO (peroxo) species during the OER is excluded. Moreover, we provide the first photoelectron spectroscopic evidence in bulk electrolyte that the higher surface-to-bulk ratio in thinner electrodes enhances the material usage involving the precipitation of a significant part of the electrode surface and near-surface active species.

8.
Int J Mol Sci ; 23(1)2021 Dec 23.
Article in English | MEDLINE | ID: mdl-35008546

ABSTRACT

Cancer remains a leading cause of death worldwide, despite many advances being made in recent decades. Changes in the tumor microenvironment, including dysregulated immunity, may contribute to carcinogenesis and cancer progression. The cysteinyl leukotriene (CysLT) pathway is involved in several signal pathways, having various functions in different tissues. We summarized major findings of studies about the roles of the CysLT pathway in cancer. Many in vitro studies suggested the roles of CysLTs in cell survival/proliferation via CysLT1 receptor (CysLT1R). CysLT1R antagonism decreased cell vitality and induced cell death in several types of cancer cells, such as colorectal, urological, breast, lung and neurological malignancies. CysLTs were also associated with multidrug resistance of cancer, and CysLT1R antagonism might reverse chemoresistance. Some animal studies demonstrated the beneficial effects of CysLT1R antagonist in inhibiting tumorigenesis and progression of some cancer types, particularly colorectal cancer and lung cancer. The expression of CysLT1R was shown in various cancer tissues, particularly colorectal cancer and urological malignancies, and higher expression was associated with a poorer prognosis. The chemo-preventive effects of CysLT1R antagonists were demonstrated in two large retrospective cohort studies. In summary, the roles of the CysLT pathway in cancer have been delineated, whereas further studies are still warranted.


Subject(s)
Cysteine/metabolism , Leukotrienes/metabolism , Neoplasms/metabolism , Signal Transduction/physiology , Animals , Apoptosis/physiology , Cell Proliferation/physiology , Humans , Retrospective Studies
9.
J Am Chem Soc ; 142(6): 2857-2867, 2020 Feb 12.
Article in English | MEDLINE | ID: mdl-31955572

ABSTRACT

Understanding the role of the oxidation state of the Cu surface and surface-adsorbed intermediate species in electrochemical CO2 reduction is crucial for the development of selective CO2-to-fuel electrocatalysts. In this study, the electrochemical CO2 reduction mechanism over the Cu catalysts with various oxidation states was studied by using in situ surface-enhanced infrared absorption spectroscopy (SEIRAS), in situ soft X-ray absorption spectroscopy (Cu L-edge), and online gas chromatography measurements. The atop-adsorbed CO (COatop) intermediate is obtained on the electrodeposited Cu surface which primarily has the oxidation state of Cu(I). COatop is further reduced, followed by the formation of C1 product such as CH4. The residual bridge-adsorbed CO (CObridge) is formed on the as-prepared Cu surface with Cu(0) which inhibits hydrocarbon formation. In contrast, the CV-treated Cu electrode prepared by oxidizing the as-prepared Cu surface contains different amounts of Cu(I) and Cu(0) states. The major theme of this work is that in situ SEIRAS results show the coexistence of COatop and CObridge as the reaction intermediates during CO2 reduction and that the selectivity of CO2-to-ethylene conversion is further enhanced in the CV-treated Cu electrode. The Cu catalysts modulated by the electrochemical method exhibit different oxidation states and reaction intermediates as well as electrocatalytic properties.

10.
J Am Chem Soc ; 141(49): 19304-19311, 2019 Dec 11.
Article in English | MEDLINE | ID: mdl-31774282

ABSTRACT

Ruthenium nanoparticles with a core-shell structure formed by a core of metallic ruthenium and a shell of ruthenium carbide have been synthesized by a mild and easy hydrothermal treatment. The dual structure and composition of the nanoparticles have been determined by synchrotron X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) analysis, and transmission electron microscopy (TEM) imaging. According to depth profile synchrotron XPS and X-ray diffraction (XRD) analysis, metallic ruthenium species predominate in the inner layers of the material, ruthenium carbide species being located on the upper surface layers. The ruthenium carbon catalysts presented herein are able to activate both CO2 and H2, exhibiting exceptional high activity for CO2 hydrogenation at low temperatures (160-200 °C) with 100% selectivity to methane, surpassing by far the most active Ru catalysts reported up to now. On the basis of catalytic studies and isotopic 13CO/12CO2/H2 experiments, the active sites responsible for this unprecedented activity can be associated with surface ruthenium carbide (RuC) species, which enable CO2 activation and transformation to methane via a direct CO2 hydrogenation mechanism. Both the high activity and the absence of CO in the gas effluent confer relevance to these catalysts for the Sabatier reaction, a chemical process with renewed interest for storing surplus renewable energy in the form of methane.

12.
Retina ; 41(9): e61-e64, 2021 09 01.
Article in English | MEDLINE | ID: mdl-33958530
13.
Angew Chem Int Ed Engl ; 54(48): 14554-8, 2015 Nov 23.
Article in English | MEDLINE | ID: mdl-26463455

ABSTRACT

Electrochemically grown cobalt on graphene exhibits exceptional performance as a catalyst for the oxygen evolution reaction (OER) and provides the possibility of controlling the morphology and the chemical properties during deposition. However, the detailed atomic structure of this hybrid material is not well understood. To elucidate the Co/graphene electronic structure, we have developed a flow cell closed by a graphene membrane that provides electronic and chemical information on the active surfaces under atmospheric pressure and in the presence of liquids by means of X-ray photoelectron spectroscopy (XPS). We found that cobalt is anchored on graphene via carbonyl-like species, namely Co(CO)x , promoting the reduction of Co(3+) to Co(2+), which is believed to be the active site of the catalyst.

14.
Kaohsiung J Med Sci ; 40(5): 467-476, 2024 May.
Article in English | MEDLINE | ID: mdl-38523603

ABSTRACT

Combining epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with an anti- vascular endothelial growth factor (VEGF) agent, bevacizumab or ramucirumab, is indicated for advanced lung adenocarcinoma harboring EGFR mutation. This study aimed to show the real-world data of combination therapy and compare the effectiveness between bevacizumab and ramucirumab in combination with an EGFR-TKI. This retrospective study enrolled 47 patients diagnosed of stage IV lung adenocarcinoma with exon 19 deletion or L858R point mutation, receiving a first-line EGFR-TKI with anti-VEGF agent, including 34 (72%) and 13 (28%) patients receiving bevacizumab and ramucirumab, respectively. The response rate was similar in both groups (p = 0.38). Patients receiving bevacizumab had similar progression free survival (PFS) as those receiving ramucirumab (median PFS: 21.9 vs. 24.2 months, p = 0.4871); similar finding was noted in overall survival (OS) (median OS: 33.5 months vs. not reached, p = 0.4618). Patients receiving ramucirumab experienced a significantly high-grade hypertension compared to those receiving bevacizumab (p = 0.0351). Multivariable Cox regression analysis found independent risk factors for worse PFS included poorer ECOG performance status, multiple (≥3) metastatic sites, brain metastasis, and pleural metastasis/effusion, while the type of anti-VEGF agent was not a risk factor. Pericardial metastasis/effusion was the only one independent risk factor for worse OS. In summary, ramucirumab may have similar effectiveness as bevacizumab in combination with an EGFR-TKI as first line therapy for advanced lung adenocarcinoma harboring susceptible EGFR mutation. Further large-scale registry-based cohort studies may be needed to validate our findings.


Subject(s)
Antibodies, Monoclonal, Humanized , Bevacizumab , Carcinoma, Non-Small-Cell Lung , ErbB Receptors , Lung Neoplasms , Mutation , Protein Kinase Inhibitors , Ramucirumab , Humans , Male , Female , ErbB Receptors/genetics , ErbB Receptors/antagonists & inhibitors , Bevacizumab/therapeutic use , Bevacizumab/administration & dosage , Antibodies, Monoclonal, Humanized/therapeutic use , Middle Aged , Aged , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Protein Kinase Inhibitors/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Treatment Outcome , Adult , Retrospective Studies , Aged, 80 and over , Neoplasm Staging , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology
15.
J Am Chem Soc ; 135(6): 2273-8, 2013 Feb 13.
Article in English | MEDLINE | ID: mdl-23339635

ABSTRACT

In situ soft X-ray absorption spectroscopy (XAS) was employed to study the adsorption and dissociation of carbon monoxide molecules on cobalt nanoparticles with sizes ranging from 4 to 15 nm. The majority of CO molecules adsorb molecularly on the surface of the nanoparticles, but some undergo dissociative adsorption, leading to oxide species on the surface of the nanoparticles. We found that the tendency of CO to undergo dissociation depends critically on the size of the Co nanoparticles. Indeed, CO molecules dissociate much more efficiently on the larger nanoparticles (15 nm) than on the smaller particles (4 nm). We further observed a strong increase in the dissociation rate of adsorbed CO upon exposure to hydrogen, clearly demonstrating that the CO dissociation on cobalt nanoparticles is assisted by hydrogen. Our results suggest that the ability of cobalt nanoparticles to dissociate hydrogen is the main parameter determining the reactivity of cobalt nanoparticles in Fischer-Tropsch synthesis.


Subject(s)
Carbon Monoxide/chemistry , Cobalt/chemistry , Metal Nanoparticles/chemistry , Adsorption , Particle Size , Surface Properties
16.
ACS Catal ; 13(11): 7488-7498, 2023 Jun 02.
Article in English | MEDLINE | ID: mdl-37288096

ABSTRACT

In the search for rational design strategies for oxygen evolution reaction (OER) catalysts, linking the catalyst structure to activity and stability is key. However, highly active catalysts such as IrOx and RuOx undergo structural changes under OER conditions, and hence, structure-activity-stability relationships need to take into account the operando structure of the catalyst. Under the highly anodic conditions of the oxygen evolution reaction (OER), electrocatalysts are often converted into an active form. Here, we studied this activation for amorphous and crystalline ruthenium oxide using X-ray absorption spectroscopy (XAS) and electrochemical scanning electron microscopy (EC-SEM). We tracked the evolution of surface oxygen species in ruthenium oxides while in parallel mapping the oxidation state of the Ru atoms to draw a complete picture of the oxidation events that lead to the OER active structure. Our data show that a large fraction of the OH groups in the oxide are deprotonated under OER conditions, leading to a highly oxidized active material. The oxidation is centered not only on the Ru atoms but also on the oxygen lattice. This oxygen lattice activation is particularly strong for amorphous RuOx. We propose that this property is key for the high activity and low stability observed for amorphous ruthenium oxide.

17.
Cancers (Basel) ; 15(7)2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37046679

ABSTRACT

Afatinib is an irreversible tyrosine kinase inhibitor (TKI) targeting the epidermal growth factor receptor (EGFR), which is utilized for the treatment of patients with advanced lung cancer that harbors EGFR mutations. No studies have evaluated the clinical efficacy of LCT in patients treated with first-line afatinib. In this study, we retrospectively enrolled patients with advanced lung adenocarcinomas harboring susceptible EGFR mutations who were diagnosed and treated with first-line afatinib in three hospitals. A total of 254 patients were enrolled, including 30 (12%) patients who received LCT (15 patients received definitive radiotherapy for the primary lung mass and 15 patients received curative surgery). Patients who received LCT had a significantly longer PFS than those who did not (median PFS: 32.8 vs. 14.5 months, p = 0.0008). Patients who received LCT had significantly longer OS than those who did not (median OS: 67.1 vs. 34.5 months, p = 0.0011). Multivariable analysis showed LCT was an independent prognostic factor for improved PFS (adjusted hazard ratio [aHR] [95% confidence interval (CI)]: 0.44 [0.26-0.73], p = 0.0016) and OS (aHR [95% CI]: 0.26 [0.12-0.54], p = 0.0004). The analyses using propensity score-weighting showed consistent results. We conclude that LCT may improve clinical outcomes, in terms of PFS and OS, in patients with advanced EGFR-mutant lung adenocarcinomas who are treated with first-line afatinib.

18.
ACS Appl Mater Interfaces ; 15(25): 30052-30059, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37318204

ABSTRACT

Catalyst degradation and product selectivity changes are two of the key challenges in the electrochemical reduction of CO2 on copper electrodes. Yet, these aspects are often overlooked. Here, we combine in situ X-ray spectroscopy, in situ electron microscopy, and ex situ characterization techniques to follow the long-term evolution of the catalyst morphology, electronic structure, surface composition, activity, and product selectivity of Cu nanosized crystals during the CO2 reduction reaction. We found no changes in the electronic structure of the electrode under cathodic potentiostatic control over time, nor was there any build-up of contaminants. In contrast, the electrode morphology is modified by prolonged CO2 electroreduction, which transforms the initially faceted Cu particles into a rough/rounded structure. In conjunction with these morphological changes, the current increases and the selectivity changes from value-added hydrocarbons to less valuable side reaction products, i.e., hydrogen and CO. Hence, our results suggest that the stabilization of a faceted Cu morphology is pivotal for ensuring optimal long-term performance in the selective reduction of CO2 into hydrocarbons and oxygenated products.

19.
Nat Nanotechnol ; 18(7): 763-771, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37231143

ABSTRACT

Heterogeneous single-atom spin catalysts combined with magnetic fields provide a powerful means for accelerating chemical reactions with enhanced metal utilization and reaction efficiency. However, designing these catalysts remains challenging due to the need for a high density of atomically dispersed active sites with a short-range quantum spin exchange interaction and long-range ferromagnetic ordering. Here, we devised a scalable hydrothermal approach involving an operando acidic environment for synthesizing various single-atom spin catalysts with widely tunable substitutional magnetic atoms (M1) in a MoS2 host. Among all the M1/MoS2 species, Ni1/MoS2 adopts a distorted tetragonal structure that prompts both ferromagnetic coupling to nearby S atoms as well as adjacent Ni1 sites, resulting in global room-temperature ferromagnetism. Such coupling benefits spin-selective charge transfer in oxygen evolution reactions to produce triplet O2. Furthermore, a mild magnetic field of ~0.5 T enhances the oxygen evolution reaction magnetocurrent by ~2,880% over Ni1/MoS2, leading to excellent activity and stability in both seawater and pure water splitting cells. As supported by operando characterizations and theoretical calculations, a great magnetic-field-enhanced oxygen evolution reaction performance over Ni1/MoS2 is attributed to a field-induced spin alignment and spin density optimization over S active sites arising from field-regulated S(p)-Ni(d) hybridization, which in turn optimizes the adsorption energies for radical intermediates to reduce overall reaction barriers.

20.
Chest ; 162(2): e85-e88, 2022 08.
Article in English | MEDLINE | ID: mdl-35940668

ABSTRACT

CASE PRESENTATION: A 54-year-old man with chronic hepatitis B was admitted to the hospital with progressive dyspnea on exertion. He reported experiencing intermittent fever, dyspnea on exertion, and relapsing pleuritic chest pain starting 6 months prior, after his first dose of the ChAdOx1 nCoV-19 vaccine. In the past 2 months, he had been admitted to the hospital twice and diagnosed with recurrent pneumonia. Under antibiotic treatment, his dyspnea and low-grade fever demonstrated waxing and waning behaviors. Migratory pulmonary consolidation, which moved from the left lower lobe to the right middle lobe, was identified and diagnosed as relapsing pneumonia. Chest CT scan was performed in a previous admission 2 months earlier that revealed multifocal peripheral consolidation in the left lower lobe and right middle lobe. His occupation required the maintenance of overall fitness, and he denied immunosuppressant use, illicit drug abuse, cigarette smoking, suspicious travel, suspicious contact, or family history. No recent history of trauma, surgery, or air travel was reported.


Subject(s)
ChAdOx1 nCoV-19 , Lung Diseases , Chest Pain/diagnosis , Diagnosis, Differential , Dyspnea/diagnosis , Dyspnea/etiology , Fever/diagnosis , Humans , Lung Diseases/diagnosis , Male , Middle Aged , Tomography, X-Ray Computed
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