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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(4): 628-636, 2024 Apr 28.
Article de Anglais, Chinois | MEDLINE | ID: mdl-39019792

RÉSUMÉ

Patients with anaplastic lymphoma kinase (ALK) fusion lung adenocarcinoma may develop drug resistance after treatment with ALK-tyrosine kinase inhibitor (ALK-TKI), and the mechanisms of this resistance are not yet fully defined. The Affiliated Hospital of Zunyi Medical University admitted a patient who was resistant to ALK fusion after ALK-TKI treatment, leading to disease progression and subsequent biopsy indicating a transformation to small cell lung cancer in September 2021. The patient, a 54-year-old female, initially presented with symptoms of cough, sputum production, and chest pain for 4 months. Chest CT showed a neoplastic lesion in the posterior segment of the right upper lobe to right lower lobe with obstructive pneumonia, metastasis in the right lower lobe, increased and enlarged mediastinal and right hilar lymph nodes, and thickening of the right hilar soft tissue. Bronchoscopy and pathological biopsy confirmed the diagnosis of lung adenocarcinoma. The results of next-generation sequencing indicated that echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) fusion is associated with tumor protein 53 (TP53) and retinoblastoma 1 (RB1) gene mutations. The patient received second-generation ALK-TKI aletinib, achieving a progression-free survival of 11 months before disease progression suggested aletinib resistance. Subsequently, the third-generation ALK-TKI lorlatinib administered for one month without efficacy, resulting in rapid systemic disease progression. The neuron specific enolase (NSE) was significantly increased, and the patient developed new pleural, pericardial, intracranial, liver, and multiple bone metastases occurred in a short period. A second biopsy indicated small cell lung cancer. Modification of treatment regimen to chemotherapy combined with immunotherapy proved effective. The mechanisms of drug resistance of ALK-TKI treatment for advanced non-small cell lung cancer with ALK fusion are complex, and small cell transformation of pathological type is one such mechanism, although rare. Concurrent TP53 and RB1 gene mutations may be characteristic of this transformation. Elevated NSE can serve as a predictive serum marker for adenocarcinoma transforming to small cell carcinoma. Timely re-biopsy and selection of subsequent treatments based on different resistance mechanisms are crucial for comprehensive disease management.


Sujet(s)
Adénocarcinome pulmonaire , Kinase du lymphome anaplasique , Tumeurs du poumon , Humains , Femelle , Adénocarcinome pulmonaire/génétique , Adénocarcinome pulmonaire/anatomopathologie , Adénocarcinome pulmonaire/traitement médicamenteux , Adulte d'âge moyen , Tumeurs du poumon/génétique , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/traitement médicamenteux , Kinase du lymphome anaplasique/génétique , Protéines de fusion oncogènes/génétique , Résistance aux médicaments antinéoplasiques/génétique , Inhibiteurs de protéines kinases/usage thérapeutique , Carcinome pulmonaire à petites cellules/génétique , Carcinome pulmonaire à petites cellules/traitement médicamenteux , Carcinome pulmonaire à petites cellules/anatomopathologie , Protéine p53 suppresseur de tumeur/génétique , Aminopyridines/usage thérapeutique
2.
Environ Sci Technol ; 58(23): 10357-10367, 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38728016

RÉSUMÉ

The urgent environmental concern of methane abatement, attributed to its high global warming potential, necessitates the development of methane oxidation catalysts (MOC) with enhanced low-temperature activity and durability. Herein, an iridium-doped PdOx nanoparticle supported on silicalite-1 zeolite (PdIr/S-1) catalyst was synthesized and applied for methane catalytic combustion. Comprehensive characterizations confirmed the atomically dispersed nature of iridium on the surface of PdOx nanoparticles, creating an Ir4f-O-Pdcus microstructure. The atomically doped Ir transferred more electrons to adjacent oxygen atoms, modifying the electronic structure of PdOx and thus enhancing the redox ability of the PdIr/S-1 catalysts. This electronic modulation facilitated methane adsorption on the Pd site of Ir4f-O-Pdcus, reducing the energy barrier for C-H bond cleavage and thereby increasing the reaction rate for methane oxidation. Consequently, the optimized PdIr0.1/S-1 showed outstanding low-temperature activity for methane combustion (T50 = 276 °C) after aging and maintained long-term stability over 100 h under simulated exhaust conditions. Remarkably, the novel PdIr0.1/S-1 catalyst demonstrated significantly enhanced activity even after undergoing harsh hydrothermal aging at 750 °C for 16 h, significantly outperforming the conventional Pd/Al2O3 catalyst. This work provides valuable insights for designing efficient and durable MOC catalysts, addressing the critical issue of methane abatement.


Sujet(s)
Iridium , Méthane , Nanoparticules , Oxydoréduction , Méthane/composition chimique , Iridium/composition chimique , Catalyse , Nanoparticules/composition chimique , Zéolites/composition chimique , Palladium/composition chimique
3.
Environ Sci Technol ; 57(48): 20370-20379, 2023 Dec 05.
Article de Anglais | MEDLINE | ID: mdl-37947383

RÉSUMÉ

Methane emissions from vehicles have made a significant contribution to the greenhouse effect, primarily due to its high global warming potential. Supported noble metal catalysts are widely employed in catalytic combustion of methane in vehicles, but they still face challenges such as inadequate low-temperature activity and deactivation due to sintering under harsh operating conditions. In the present work, a series of encapsulated structured catalysts with palladium nanoparticles confined in hydrophobic silicalite-2 were prepared by an in situ synthesis method. Based on various characterization methods, including XRD, HR-TEM, XPS, H2-TPR, O2-TPD, H2O-TPD, CH4-TPR, Raman, and in situ DRIFTS-MS, it was confirmed that PdOx nanoparticles were mainly encapsulated inside the silicalite-2 zeolite, which further maintained the stability of the nanoparticles under harsh conditions. Specifically, the 3Pd@S-2 sample exhibited high catalytic activity for methane oxidation even after harsh hydrothermal aging at 750 °C for 16 h and maintained long-term stability at 400 °C for 130 h during wet methane combustion. In situ Raman spectroscopy has confirmed that PdOx species act as active species for methane oxidation. During this reaction, methane reacts with PdOx to produce CO2 and H2O, while simultaneously reducing PdOx to metallic Pd species, which is further reoxidized by oxygen to replenish the PdOx catalyst.


Sujet(s)
Nanoparticules métalliques , Méthane , Méthane/composition chimique , Palladium/composition chimique , Oxydoréduction , Catalyse
4.
Environ Sci Technol ; 57(39): 14760-14767, 2023 10 03.
Article de Anglais | MEDLINE | ID: mdl-37724749

RÉSUMÉ

The mechanistic cause of the enhancement of the C3H6-SCR activity of Ag/Al2O3 by trace Pd doping and the corresponding structure-property relationship were investigated. Pd doping enhanced the water resistance of Ag/Al2O3 for C3H6-SCR by changing the reaction pathway. Under wet conditions, a series of in situ DRIFT studies indicated that the production of an active acetate intermediate on Ag/Al2O3 was suppressed during the partial oxidation of C3H6, while trace Pd doping promoted the formation of another active intermediate, an enolic species. Furthermore, a pathway for the formation of enolic species by the reaction of acrylate with hydroxyl species was proposed. DFT calculations revealed that the surface of Ag clusters was easily covered by hydroxyl in the presence of water vapor, which could inhibit the formation of acetates. Doping with Pd facilitated the activation of acrylate which might further react with hydroxyl species to form enolic species. These findings can be helpful for the future design of efficient HC-SCR catalysts.


Sujet(s)
Oxyde d'aluminium , Oxydoréduction , Catalyse
5.
ACS Omega ; 8(15): 13944-13954, 2023 Apr 18.
Article de Anglais | MEDLINE | ID: mdl-37091366

RÉSUMÉ

Ammonia selective catalytic oxidation (NH3-SCO) is a commercial technology applied to diesel vehicles to eliminate ammonia leakage. In this study, a series of Pt/Al2O3 catalysts were synthesized by an impregnation method, and the state of Pt species was carefully adjusted by heat treatment. These Pt/Al2O3 catalysts were further systematically characterized by Brunauer-Emmett-Teller, X-ray diffraction, X-ray photoelectron spectroscopy, X-ray absorption fine structure, UV-vis, H2-tempertaure-programmed reduction, and NH3-temperature-programmed desorption. The characterization results showed that dispersed oxidized Pt species were present on conventional Pt/Al2O3 samples, while high-temperature treatment induced the aggregation of platinum species to form metallic Pt nanoparticles. The Pt/Al2O3 catalysts treated at high temperatures showed superior activity and water tolerance in the NH3-SCO reaction. Diffuse reflectance infrared Fourier-transform spectroscopy combined with mass spectrometry experiments revealed that the Lewis acid sites were more reactive than the Brønsted acid sites. Moreover, compared to oxidized Pt species, metallic Pt nanoparticles were beneficial for oxygen activation and were less affected by water vapor, thus contributing to the superior activity and water tolerance of Pt/Al-800.

6.
J Environ Sci (China) ; 123: 15-29, 2023 Jan.
Article de Anglais | MEDLINE | ID: mdl-36521980

RÉSUMÉ

Diesel vehicles have caused serious environmental problems in China. Hence, the Chinese government has launched serious actions against air pollution and imposed more stringent regulations on diesel vehicle emissions in the latest China VI standard. To fulfill this stringent legislation, two major technical routes, including the exhaust gas recirculation (EGR) and high-efficiency selective catalytic reduction (SCR) routes, have been developed for diesel engines. Moreover, complicated aftertreatment technologies have also been developed, including use of a diesel oxidation catalyst (DOC) for controlling carbon monoxide (CO) and hydrocarbon (HC) emissions, diesel particulate filter (DPF) for particle mass (PM) emission control, SCR for the control of NOx emission, and an ammonia slip catalyst (ASC) for the control of unreacted NH3. Due to the stringent requirements of the China VI standard, the aftertreatment system needs to be more deeply integrated with the engine system. In the future, aftertreatment technologies will need further upgrades to fulfill the requirements of the near-zero emission target for diesel vehicles.


Sujet(s)
Polluants atmosphériques , Pollution de l'air , Polluants atmosphériques/analyse , Emissions des véhicules/prévention et contrôle , Emissions des véhicules/analyse , Pollution de l'air/prévention et contrôle , Pollution de l'air/analyse , Catalyse , Chine , Essence , Matière particulaire/analyse , Véhicules motorisés
7.
J Environ Sci (China) ; 126: 333-347, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-36503761

RÉSUMÉ

Pd/Al2O3 catalysts supported on Al2O3 of different particle sizes were synthesized and applied in methane combustion. These catalysts were systematically characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), high resolution-transmission electron microscopy (HR-TEM), high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), H2-temperature-programmed reduction (H2-TPR), O2-temperature-programmed oxidation (O2-TPO), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS). The characterization results indicated that nano-sized Al2O3 enabled the uniform dispersion of palladium nanoparticles, thus contributing to the excellent catalytic performance of these nano-sized Pd/Al2O3 catalysts. Among them, Pd/Al2O3-nano-10 (Pd/Al2O3 supported by alumina with an average particle size of 10 nm) showed superior catalytic activity and stability for methane oxidation under harsh practical conditions. It maintained excellent catalytic performance for methane oxidation for 50 hr and remained stable even after harsh hydrothermal aging in 10 vol.% steam at 800°C for 16 hr. Characterization results revealed that the strong metal-support interactions and physical barriers provided by Al2O3-nano-10 suppressed the coalescence ripening of palladium species, and thus contributed to the superior sintering resistance of the Pd/Al2O3-nano-10 catalyst.


Sujet(s)
Nanoparticules métalliques , Palladium , Oxyde d'aluminium , Méthane , Catalyse
8.
Clin Interv Aging ; 17: 1151-1161, 2022.
Article de Anglais | MEDLINE | ID: mdl-35942335

RÉSUMÉ

Purpose: Guidelines have not recommended routine transthoracic echocardiography (TTE) for elderly patients prior to noncardiac surgery. We aimed to evaluate the significance of preoperative TTE to predict perioperative cardiac complications (PCCs) for elderly patients with coronary artery disease (CAD) undergoing noncardiac surgery. Patients and methods: We retrospectively reviewed 2204 patients over 65 years of age with CAD who underwent TTE before intermediate- or high-risk noncardiac surgery in a teaching hospital in China between September 2013 and August 2019. The revised cardiac risk index (RCRI) was assessed. PCCs comprised acute coronary syndrome, heart failure, new-onset severe arrhythmia, nonfatal cardiac arrest, and cardiac death. Logistic regression was used to build the prediction model for PCCs. Discrimination was evaluated using receiver operating characteristic curves, and a nomogram of the predictive model was constructed. Results: PCCs occurred in 189 (8.6%) patients. Multivariable analysis showed that eight clinical risk factors (age, history of myocardial infarction, insulin therapy for diabetes, New York Heart Association classification, preoperative serum creatinine, preoperative electrocardiogram ST-T abnormality and pathological Q wave, and American Society of Anesthesiologists classification) and five TTE parameters (left atrial anteroposterior dimension, left ventricular ejection fraction, left ventricular diastolic dysfunction, pulmonary hypertension, and regional ventricular wall motion abnormality) were associated with PCCs. The receiver operating characteristic curve for the clinical plus TTE model provided better discrimination for PCCs compared with the RCRI model (area under the curve: 0.731 vs 0.564; P < 0.001) and the clinical model (area under the curve: 0.731 vs 0.697, P = 0.001), respectively. The clinical plus TTE model was presented as a prognostic nomogram. Conclusion: Preoperative TTE may help predict PCCs in elderly patients with CAD undergoing noncardiac surgery, and the prognostic nomogram from this study appeared to be useful for the assessment of perioperative cardiac risk.


Sujet(s)
Maladie des artères coronaires , Cardiopathies , Procédures de chirurgie opératoire , Sujet âgé , Troubles du rythme cardiaque/étiologie , Maladie des artères coronaires/imagerie diagnostique , Échocardiographie/méthodes , Cardiopathies/imagerie diagnostique , Cardiopathies/étiologie , Humains , Période périopératoire , Complications postopératoires/imagerie diagnostique , Complications postopératoires/épidémiologie , Complications postopératoires/étiologie , Études rétrospectives , Appréciation des risques , Facteurs de risque , Débit systolique , Fonction ventriculaire gauche
9.
Brain Sci ; 12(6)2022 May 27.
Article de Anglais | MEDLINE | ID: mdl-35741578

RÉSUMÉ

Intraoperative hypothermia is very common and leads to memory decline. The hippocampus is responsible for memory formation. As a functional core area, the cornu ammonis 1 (CA1) region of the hippocampus contains abundant blood vessels and is susceptible to ischemia. The aim of the study was to explore vascular function and neuronal state in the CA1 region of rats undergoing intraoperative hypothermia. The neuronal morphological change and activity-regulated cytoskeleton-associated protein (Arc) expression were evaluated by haematoxylin-eosin staining and immunofluorescence respectively. Histology and immunohistochemistry were used to assess vascular function. Results showed that intraoperative hypothermia inhibited the expression of vascular endothelial growth factor and endothelial nitric oxide synthase, and caused reactive oxygen species accumulation. Additionally, the phenotype of vascular smooth muscle cells was transformed from contractile to synthetic, showing a decrease in smooth muscle myosin heavy chain and an increase in osteopontin. Ultimately, vascular dysfunction caused neuronal pyknosis in the CA1 region and reduced memory-related Arc expression. In conclusion, neuronal disorder in the CA1 region was caused by intraoperative hypothermia-related vascular dysfunction. This study could provide a novel understanding of the effect of intraoperative hypothermia in the hippocampus, which might identify a new research target and treatment strategy.

10.
J Hazard Mater ; 431: 128528, 2022 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-35231814

RÉSUMÉ

A mesoporous LaCoO3 perovskite oxide (LaCoO3-Meso) with three-dimensionally ordered helical interwoven structure was synthesized by a nano-casting method using KIT-6 as the hard template. The obtained LaCoO3-Meso with high surface area was tested for its catalytic performance in the NOx storage and reduction (NSR) reaction and compared with a sample synthesized by the conventional sol-gel method. The LaCoO3-Meso showed a significant advantage for NOx storage, with a NOx storage capacity 2 times higher than the regular sample. LaCoO3-Meso also exhibited improved NSR catalytic performance in the 150-450 °C temperature range, especially within 350-400 °C, where the NOx conversion was raised for 40%. The results of X-ray photoelectron spectroscopy and X-ray absorption fine structure measurements suggested the presence of a high concentration of oxygen defects on the LaCoO3-Meso surface. Further results provided by temperature programmed reduction and temperature programmed desorption indicated that the oxygen defects not only increase the amount of trapped NOx, but also improve the low-temperature redox performance of the catalyst. The lower stability of NOx species adsorbed on oxygen defects promotes the NOx release step in the NSR reaction and benefits the regeneration of storage sites.

11.
Environ Sci Technol ; 56(6): 3710-3718, 2022 03 15.
Article de Anglais | MEDLINE | ID: mdl-35195409

RÉSUMÉ

Selective catalytic reduction of NOx by ammonia (NH3-SCR) on V2O5/TiO2 catalysts is a widely used commercial technology in power plants and diesel vehicles due to its high elimination efficiency for NOx removal. However, the mechanistic aspects of the NH3-SCR reaction, especially the active sites on the V2O5/TiO2 catalysts, are still a puzzle. Herein, using combined operando spectroscopy and density functional theory calculations, we found that the reactivity of the Lewis acid site was significantly overestimated due to its conversion to the Brønsted acid site. Such interconversion makes it challenging to measure the intrinsic reactivity of different acid sites accurately. In contrast, the abundant V-OH Brønsted acid sites govern the overall NOx reduction rate in realistic exhaust containing water vapor. Moreover, the vanadia species cycle between V5+═O and V4+-OH during NOx reduction, and the re-oxidation of V4+ species to form V5+ is the rate-determining step.


Sujet(s)
Oxydes d'azote , Titane , Ammoniac/composition chimique , Catalyse , Domaine catalytique , Oxydes d'azote/composition chimique , Oxydoréduction , Oxydes , Titane/composition chimique
12.
Brain Sci ; 12(1)2022 Jan 12.
Article de Anglais | MEDLINE | ID: mdl-35053838

RÉSUMÉ

Intraoperative hypothermia is a common complication during operations and is associated with several adverse events. Postoperative cognitive dysfunction (POCD) and its adverse consequences have drawn increasing attention in recent years. There are currently no relevant studies investigating the correlation between intraoperative hypothermia and POCD. The aim of this study was to assess the effects of intraoperative hypothermia on postoperative cognitive function in rats undergoing exploratory laparotomies and to investigate the possible related mechanisms. We used the Y-maze and Morris Water Maze (MWM) tests to assess the rats' postoperative spatial working memory, spatial learning, and memory. The morphological changes in hippocampal neurons were examined by haematoxylin-eosin (HE) staining and hippocampal synaptic plasticity-related protein expression. Activity-regulated cytoskeletal-associated protein (Arc), cyclic adenosine monophosphate-response element-binding protein (CREB), S133-phosphorylated CREB (p-CREB [S133]), α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor 1 (AMPAR1), and S831-phosphorylated AMPAR1 (p-AMPAR1 [S831]) were evaluated by Western blotting. Our results suggest a correlation between intraoperative hypothermia and POCD in rats and that intraoperative hypothermia may lead to POCD regarding impairments in spatial working memory, spatial learning, and memory. POCD induced by intraoperative hypothermia might be due to hippocampal neurons damage and decreased expression of synaptic plasticity-related proteins Arc, p-CREB (S133), and p-AMPAR1 (S831).

13.
ISA Trans ; 125: 330-337, 2022 Jun.
Article de Anglais | MEDLINE | ID: mdl-34215439

RÉSUMÉ

In this paper, the game theory approaches are used to solve the power schedule problem in the wireless communication network. All sensors can be affected by DoS attackers when transmitting data. The game process between sensors and attackers is established as Bayesian game process. First, a Nash Equilibrium (NE) framework is proposed based on the object function consist of signal-to-interference-and-noise-ratio (SINR). Second, the total power of sensors is considered to have two types, and each type has some power levels. Unlike NE, both sensors and attackers no longer learn the specific total power of each other. However, sensors and attackers can get the type distribution of each other. In this situation, the strategies of sensors and attackers are formulated by introducing the Harsanyi transformation, and the Bayesian Nash Equilibrium (BNE) is solved. Finally, the Bayesian equilibrium strategies used by both offensive and defensive players are compared in the numerical example, which can illustrate the advantage of making full use of incomplete information.

14.
Dis Markers ; 2021: 4495489, 2021.
Article de Anglais | MEDLINE | ID: mdl-34853621

RÉSUMÉ

An interaction between hypoxia and immunity has been confirmed in tumor tissue. However, there is no combined biomarker for diagnosis on this basis. Therefore, we developed a scoring formula based on markers of hypoxia and immunity. Firstly, the hypoxia-immune formula of lung adenocarcinoma (LUAD) was derived using LASSO-Cox regression in three cohorts from public database, and the corresponding score was calculated for each patient. The formula is as follows: combined hypoxia and immune index (CIHI) = LDHA expression × 0.2252 + GAPDH expression × 0.0727 + ANGPTL4 expression × 0.0724 + VEGFC expression × 0.1911 + DKK1 expression × 0.1355 + ADM expression × 0.0588 + BTK expression × -0.1659. Meanwhile, patients were divided into groups according to high and low CIHI, and expression profiles of hypoxia markers and immune markers were analyzed in different groups. CIHI was used to confirm that patients with high CIHI represented a state of hypoxiahigh-immunitylow, which had worse overall survival. We also discussed the evaluation value in the immune microenvironment and clinical application of CIHI. In conclusion, this study developed and validated a hypoxia-immune formula that can guide hypoxia modifier treatment and immunotherapy in LUAD.


Sujet(s)
Adénocarcinome pulmonaire/anatomopathologie , Marqueurs biologiques tumoraux/génétique , Hypoxie/physiopathologie , Tumeurs du poumon/anatomopathologie , Lymphocytes TIL/immunologie , Microenvironnement tumoral , Adénocarcinome pulmonaire/traitement médicamenteux , Adénocarcinome pulmonaire/génétique , Adénocarcinome pulmonaire/immunologie , Femelle , Études de suivi , Humains , Immunothérapie , Tumeurs du poumon/traitement médicamenteux , Tumeurs du poumon/génétique , Tumeurs du poumon/immunologie , Mâle , Adulte d'âge moyen , Pronostic , Taux de survie , Transcriptome
15.
Front Aging Neurosci ; 13: 654761, 2021.
Article de Anglais | MEDLINE | ID: mdl-34122040

RÉSUMÉ

Neuropeptide Y (NPY) signaling plays an essential role in gating the pruritic afferent information in the spinal cord. Recent studies revealed that the aging process down-regulated the expression of NPY in the central nervous system. We propose that the lack of spinal NPY may be involved in certain types of pruritus in the elderly population. This study was designed to investigate the role of NPY in aging-induced itch using the senile mouse model. The expression of NPY in the spinal dorsal horn was compared between young (2 months old) and aged (24 months old) mice. Western blotting and immunohistochemistry showed that the expression of NPY was significantly reduced in the spinal dorsal horn in aged mice. In addition, a neuronal maker of apoptosis, TUNEL, was detected in the NPY positive neurons only in the aged spinal cord. Behavioral assay indicated that light mechanical stimulus evoked significantly more scratching in the aged than in the young mice, whereas chemical-evoked itch and pain-related behaviors were not altered. Intrathecal injection of either NPY or LP-NPY, a NPY receptor 1 (NPY1R) agonist, significantly alleviated the mechanically evoked itch in aged mice without altering the responses to chemical pruritogens. Our study suggested that downregulation of spinal NPY in the aged mice might play a role in the higher incidence of the mechanically evoked itch than that in the young mice. Therapies targeting the NPY system might serve as a potential strategy for alleviating the pruritic symptoms among the elderly population.

16.
ACS Omega ; 5(45): 29593-29600, 2020 Nov 17.
Article de Anglais | MEDLINE | ID: mdl-33225191

RÉSUMÉ

Ag/Al2O3 catalysts containing different precipitable silver compounds (AgCl, Ag2SO4, and Ag3PO4) were synthesized and investigated for NOx reduction in H2-assisted C3H6-selective catalytic reduction (SCR). The samples were systematically characterized by N2 adsorption, X-ray diffraction (XRD), UV-Vis, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HR-TEM). N2 adsorption revealed that the introduction of anions (Cl-, SO4 2-, and PO4 3-) did not significantly affect the surface and structural properties of the Al2O3 support. However, XRD patterns and HR-TEM images indicated that the addition of Cl- anions caused the agglomeration of silver species to form large AgCl particles on the AgCl/Al2O3 catalysts. In contrast, the silver species dispersed well on Ag2SO4/Al2O3 and Ag3PO4/Al2O3 catalysts. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) revealed that partial oxidation of C3H6 on Ag2SO4/Al2O3 produced large amounts of reactive enolic species, while it tended to yield inert formate on AgCl/Al2O3. As a result, Ag2SO4/Al2O3 catalysts, especially 3% Ag2SO4/Al2O3, exhibited superior water and sulfur tolerance in H2-assisted C3H6-SCR.

17.
Clin Interv Aging ; 15: 1181-1191, 2020.
Article de Anglais | MEDLINE | ID: mdl-32801670

RÉSUMÉ

PURPOSE: Ever-increasing noncardiac surgeries are performed in patients aged 80 years or over with coronary artery disease (CAD). The objective of the study was to explore the incidence and risk factors of perioperative cardiac complications (PCCs) for the oldest-old patients with CAD undergoing noncardiac surgery, which have not been evaluated previously. PATIENTS AND METHODS: A total of 547 patients, aged over 80 years, with a history of CAD who underwent noncardiac surgery were enrolled in this retrospective study. Perioperative clinical variables were extracted from the electronic medical records database. The primary outcome was the occurrence of PCCs intraoperatively or within 30 days postoperatively, defined as any of the following complications: acute coronary syndrome, heart failure, new-onset severe arrhythmia, nonfatal cardiac arrest, and cardiac death. Multivariate logistic regression analysis and multivariate Cox regression model were both performed to estimate the risk factors of PCCs. The incidence of PCCs overtime was illustrated by the Kaplan-Meier curve with a stratified Log-rank test. RESULTS: One hundred six (19.4%) patients developed at least one PCC, and 15 (2.7%) patients developed cardiac death. The independent risk factors contributing to PCCs were age ≧85 years; body mass index ≧30 kg/m2; the history of angina within 6 months; metabolic equivalents <4; hypertension without regular treatment; preoperative ST-T segment abnormality; anesthesia time >3 h and drainage ≧200 mL within 24 h postoperatively. CONCLUSION: The incidence of PCCs in elderly patients over 80 years with CAD who underwent noncardiac surgery was high. Comprehensive preoperative evaluation, skilled surgical technique, and regular postoperative monitoring may help to reduce the occurrence of PCCs in this high-risk population.


Sujet(s)
Maladie des artères coronaires/chirurgie , Complications peropératoires , Complications postopératoires/épidémiologie , Sujet âgé de 80 ans ou plus , Troubles du rythme cardiaque/épidémiologie , Maladie des artères coronaires/épidémiologie , Femelle , Défaillance cardiaque/épidémiologie , Humains , Incidence , Mâle , Période postopératoire , Soins préopératoires , Études rétrospectives , Facteurs de risque
18.
Environ Sci Technol ; 53(18): 10855-10862, 2019 Sep 17.
Article de Anglais | MEDLINE | ID: mdl-31418541

RÉSUMÉ

Adsorption is an efficient method for atmospheric NOx abatement under ambient conditions; however, traditional adsorbents suffer from limited adsorption capacity and byproduct formation. Developing a low-cost material with high capacity for atmospheric NO2 elimination remains a challenge. Here, we synthesized a nanodispersed Mn3O4/γ-Al2O3 (Mn/Al) material that exhibits excellent ability to remove NO2. The 10 wt % Mn/Al sample showed the highest removal capacity, with 247.6 mgNO2/gMn/Al, which is superior to that of activated carbon (42.6 mgNO2/g). There were no byproducts produced when Mn/Al was tested with ppb-level NO2. The NO2 abatement mechanism with Mn/Al is different from physisorption or chemisorption. NO2 removal is mainly a catalytic process in air, during which surface hydroxyls and lattice oxygen are involved in the oxidation of NO2 to nitrate. In contrast, a chemical reaction between Mn3+ and NO2 is dominant in N2, where Mn3+ is converted into Mn4+ and NO2 is reduced to nitrite. Washing with deionized water is an effective and convenient method for the regeneration of saturated Mn/Al, and an 86% adsorption capacity was recovered after one washing. The results suggest that this low-cost Mn/Al material with easy preparation and regeneration is a promising candidate material for atmospheric NO2 elimination.


Sujet(s)
Nitrates , Adsorption , Catalyse , Oxydoréduction , Température
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(10): 1111-1116, 2016 Oct 28.
Article de Chinois | MEDLINE | ID: mdl-27807337

RÉSUMÉ

Solitary fibrous tumor (SFT) is a derived mesenchymal tumor from spindle cells, mostly occurred in the pleura. To analyze the clinical features of the SFT, data for a patient with SFT that involved in the pleura were retrospectively analyzed by assisted thoracoscope in the Affiliated Hospital of Zunyi Medical College in August 2015. The male patient was 45 years old, who showed the main clinical symptoms of chest pain, cough, sputum, and dyspnea. Large amount of right pleural effusion, chest space-occupying lesions were found by chest CT, suggesting a malignant tumor with metastasis at the 2nd and 3rd right rib. Immunohistochemical results showed: CD34 (+), cytokeratin (-), cytokeratin 5/6 (-), calretinin (-), epithelial membrane antigen(-), mesothelial cell (-), vimentin (++), Wilm's tumor-1 (+), Bcl-2 (+), CD56 (-), CD99 (+), desmin (-), and thyroid transcription factor-1 (-). It was diagnosed as SFT at right side wall layer pleura. SFT is a rare disease and it may occur at any site in the body. It lacks characteristic clinical symptoms and can be asymptomatic, or displays symptoms such as cough, chest pain, dyspnea, and hemoptysis. SFTs can only be conclusively diagnosed based on histopathologic and immunohistochemical characteristics of the tumor, and they are mostly benign. The main treatment for SFTs is the complete surgical resection. The prognosis for this disease is relatively good.


Sujet(s)
Tumeurs fibreuses solitaires de la plèvre/diagnostic , Calbindine-2 , Humains , Immunohistochimie , Mâle , Adulte d'âge moyen , Pronostic , Tumeurs fibreuses solitaires de la plèvre/chirurgie , Facteur-1 de transcription de la thyroïde , Tomodensitométrie
20.
Aging Clin Exp Res ; 25(4): 479-81, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-23780691

RÉSUMÉ

Desmopressin is a synthetic replacement for vasopressin, which is used to reduce perioperative blood loss. However, seizure attacks were observed in patients after administration of desmopressin. Here, we reported two cases of adult Chinese patients experienced generalized tonic-clonic seizures associated with severe hyponatremia caused by intravenously administered desmopressin after surgery. The patients' neurological conditions returned to baseline quickly and completely following discontinuation of desmopressin, control of the seizures, and fluid intake restriction. These cases illustrate the importance of periodic monitoring of electrolyte concentrations and fluid intake during use of desmopressin.


Sujet(s)
Desmopressine/effets indésirables , Grand mal épileptique/induit chimiquement , Administration par voie intraveineuse , Adulte , Femelle , Hémostatiques , Humains , Hyponatrémie/induit chimiquement , Mâle , Adulte d'âge moyen
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