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1.
J Am Chem Soc ; 146(29): 20059-20068, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-38994646

ABSTRACT

Ultrasmall metallic nanoclusters (NCs) protected by surface ligands represent the most promising catalytic materials; yet understanding the structure and catalytic activity of these NCs remains a challenge due to dynamic evolution of their active sites under reaction conditions. Herein, we employed a single-nanoparticle collision electrochemistry method for real-time monitoring of the dynamic electrocatalytic activity of a single fully ligand-protected Au25(PPh3)10(SC2H4Ph)5Cl22+ nanocluster (Au252+ NC) at a cavity carbon nanoelectrode toward the oxygen reduction reaction (ORR). Our experimental results and computational simulations indicated that the reversible depassivation and passivation of ligands on the surface of the Au252+ NC, combined with the dynamic conformation evolution of the Au259+ core, led to a characteristic current signal that involves "ON-OFF" switches and "ON" fluctuations during the ORR process of a single Au252+ NC. Our findings reinvent the new perception and comprehension of the structure-activity correlation of NCs at the atomic level.

2.
Angew Chem Int Ed Engl ; : e202411508, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39014940

ABSTRACT

The conversion of CO2 to C2 through photocatalysis poses significant challenges, and one of the biggest hurdles stems from the sluggishness of the multi-electron transfer process. Herein, taking metal-organic framework (PFC-98) as a model photocatalyst, we report a new strategy to facilitate charge separation. This strategy involves matching the energy levels of the lowest unoccupied node and linker orbitals of the MOF, thereby creating the lowest unoccupied crystal orbital (LUCO) delocalized over both the node and linker. This feature enables the direct excitation of electrons from photosensitive linker to the catalytic centers, achieving a direct charge transfer (DCT) pathway. For comparison, an isoreticular MOF (PFC-6) based on analogue components but with far apart frontier energy level was synthesized. The delocalized LUCO caused the presence of an internal charge-separated state (ICS), prolonging the excited state lifetime and further inhibiting the electron-hole recombination. The presence of an internal charge-separated state (ICS) prolongs the excited state lifetime and further inhibits the electron-hole recombination. Moreover, it also induced abundant electrons accumulating at the catalytic sites, enabling the multi-electron transfer process. As a result, the material featuring delocalized LUCO exhibits superior overall CO2 photocatalytic performance with high C2 production yield and selectivity.

3.
Front Endocrinol (Lausanne) ; 15: 1405142, 2024.
Article in English | MEDLINE | ID: mdl-38904052

ABSTRACT

Objectives: Thyroid cancer rarely occurs in children and adolescents. Molecular markers such as BRAF, RAS, and RET/PTC have been widely used in adult PTC. It is currently unclear whether these molecular markers have equivalent potential for application in pediatric patients. This study aims to explore the potential utility of a multi-gene conjoint analysis based on next-generation targeted sequencing for pediatric papillary thyroid carcinoma (PTC). Materials and methods: The patients diagnosed with PTC (aged 18 years or younger) in the pediatrics department of Lishui District Hospital of Traditional Chinese Medicine were retrospectively screened. A targeted enrichment and sequencing analysis of 116 genes associated with thyroid cancer was performed on paraffin-embedded tumor tissues and paired paracancerous tissue of fifteen children (average age 14.60) and nine adults (average age 49.33) PTC patients. Demographic information, clinical indicators, ultrasonic imaging information and pathological data were collected. The Kendall correlation test was used to establish a correlation between molecular variations and clinical characteristics in pediatric patients. Results: A sample of 15 pediatric PTCs revealed a detection rate of 73.33% (11/15) for driver gene mutations BRAF V600E and RET fusion. Compared to adult PTCs, the genetic mutation landscape of pediatric PTCs was more complex. Six mutant genes overlap between the two groups, and an additional seventeen unique mutant genes were identified only in pediatric PTCs. There was only one unique mutant gene in adult PTCs. The tumor diameter of pediatric PTCs tended to be less than 4cm (p<0.001), and the number of lymph node metastases was more than five (p<0.001). Mutations in specific genes unique to pediatric PTCs may contribute to the onset and progression of the disease by adversely affecting hormone synthesis, secretion, and action mechanisms, as well as the functioning of thyroid hormone signaling pathways. But, additional experiments are required to validate this hypothesis. Conclusion: BRAF V600E mutation and RET fusion are involved in the occurrence and development of adolescent PTC. For pediatric thyroid nodules that cannot be determined as benign or malignant by fine needle aspiration biopsy, multiple gene combination testing can provide a reference for personalized diagnosis and treatment by clinical physicians.


Subject(s)
Mutation , Proto-Oncogene Proteins B-raf , Thyroid Cancer, Papillary , Thyroid Neoplasms , Humans , Female , Adolescent , Thyroid Cancer, Papillary/genetics , Thyroid Cancer, Papillary/diagnosis , Thyroid Cancer, Papillary/pathology , Thyroid Cancer, Papillary/therapy , Male , Child , Thyroid Neoplasms/genetics , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/pathology , Thyroid Neoplasms/therapy , Retrospective Studies , Proto-Oncogene Proteins B-raf/genetics , Adult , Middle Aged , Biomarkers, Tumor/genetics , Proto-Oncogene Proteins c-ret/genetics , High-Throughput Nucleotide Sequencing/methods , DNA Mutational Analysis/methods
4.
Angew Chem Int Ed Engl ; : e202404598, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38945836

ABSTRACT

Acetic acid (AA), a vital compound in chemical production and materials manufacturing, is conventionally synthesized by starting with coal or methane through multiple steps including high-temperature transformations. Here we present a new synthesis of AA from ethane through photocatalytic selective oxidation of ethane by H2O2 at 0-25°C. The catalyst designed for this process comprises g-C3N4 with anchored Pd1 single-atom sites. In-situ studies and computational simulation suggest the immobilized Pd1 atom becomes positively charged under photocatalytic condition. Under photoirradiation, the holes on the Pd1 single-atom of OH-Pd1Å/g-C3N4 serves as a catalytic site for activating a C-H instead of C-C of C2H6 with a low activation barrier of 0.14 eV, through a concerted mechanism. Remarkably, the selectivity for synthesizing AA reaches 98.7%, achieved under atmospheric pressure of ethane at 0°C. By integrating photocatalysis with thermal catalysis, we introduce a highly selective, environmentally friendly, energy-efficient synthetic route for AA, starting from ethane, presenting a promising alternative for AA synthesis. This integration of photocatalysis in low-temperature oxidation demonstrates a new route of selective oxidation of light alkanes.

5.
Nano Lett ; 24(18): 5444-5452, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38639448

ABSTRACT

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO2) with water (H2O) in the absence of any photosensitizer, sacrificial agents, or cocatalysts. The production rate of carbon monoxide (CO) reaches as high as 158.1 µmol g-1 h-1 with near 100% CO selectivity, which is accompanied by the oxidation of H2O to oxygen. Both theoretical and experimental results confirm that the key lies in achieving exceptional photoinduced charge separation and low exciton binding. We anticipate that our findings will facilitate new possibilities for the development of semiconducting COFs with structural diversity and functional variability.

6.
Angew Chem Int Ed Engl ; 63(20): e202401568, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38506189

ABSTRACT

Maintaining high conversion under the premise of high oxygenates selectivity in syngas conversion is important but a formidable challenge in Rh catalysis. Monometallic Rh catalysts provide poor oxygenate conversion efficiency, and efforts have been focused on constructing adjacent polymetallic sites; however, the one-pass yields of C2+ oxygenates over the reported Rh-based catalysts were mostly <20 %. In this study, we constructed a monometallic Rh catalyst encapsulated in UiO-67 (Rh/UiO-67) with enhanced proximity to dual-site Rh1,2-Rhn ensembles. Unexpectedly, this catalyst exhibited high efficacy for oxygenate synthesis from syngas, giving a high oxygenate selectivity of 72.0 % with a remarkable CO conversion of 50.4 %, and the one-pass yield of C2+ oxygenates exceeded 25 %. The state-of-the-art characterizations further revealed the spontaneous formation of an ensemble of Rh single atoms/dimers (Rh1,2) in the proximity of ultrasmall Rh clusters (Rhn) confined within the nanocavity of UiO-67, providing adjacent Rh+-Rh0 dual sites dynamically during the reaction that promote the relay of the undissociated CHO species to the CHx species. Thus, our results open a new route for designing highly efficient Rh catalysts for the conversion of syngas to oxygenates by precisely tuning the ensemble and proximity of the dual active sites in a confined space.

7.
J Chem Theory Comput ; 20(3): 1386-1397, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38300767

ABSTRACT

The embedded cluster method has been used extensively in the study of the chemical and physical properties of metal oxides. This method has been a popular tool due to its relatively high accuracy and low computational cost. An even more promising option may entail integrating the embedded cluster method with the combined quantum mechanical and molecular mechanical (QM/MM) approach, thereby enabling further consideration of interactions within the entire system for superior results. We aim to accurately model the chemistry of metal oxides using this combined scheme. Here, using the prototypical MgO(100) surface as a test system, with Mg9O14 as the cluster in the quantum mechanical region, we show that the embedded cluster with untailored boundary effective core potentials (ECPs) can have frontier orbital energy levels that substantially deviate from the quantum mechanical reference results. This occurs even when Mg9O9, which retains the stoichiometry of MgO, is used as the cluster in the quantum mechanical region. As a result, the chemical properties of the embedded cluster models differ from those of the quantum mechanical reference model. To address this issue, we propose a new variant of the embedded cluster method called the level-shifted embedded cluster (LSEC) method, which allows the energy levels to be shifted to match the reference levels by tuning the boundary ECPs. Our validation calculations on the adsorption of various adsorbates with different properties on the MgO(100) surface show that the overall performance of QM/MM with the LSEC method is excellent for the adsorption energies, geometries, and charge properties. The excellent performance holds for both the nonstoichiometric and stoichiometric clusters (i.e., Mg9O14 and Mg9O9, respectively), demonstrating the robustness of the LSEC method. We expect that the LSEC method can be combined with QM/MM or used separately for future chemical studies of metal oxides and other ionically bonded systems.

8.
Sci Rep ; 13(1): 22912, 2023 12 21.
Article in English | MEDLINE | ID: mdl-38129421

ABSTRACT

The effect of MDANP effects on ER stress signalling not well known or elucidated. Endoplasmic reticulum (ER) stress plays a critical role in necrotizing enterocolitis (NEC) pathogenesis through the PERK-eIF2ɑ-QRICH1 axis. The present study aimed to explore the protective effects of MDANP in NEC development. Firstly, a function screening was designed to identify the candidate peptides in human milk, and then the identified peptides were validated in NEC patients. In vivo, NEC was induced in mice pups and divided into four groups: (1) control group, (2) NEC group, (3) MDANP + NEC group, and (4) NS + NEC group. In vitro, lentivirus-mediated QRICH1 silencing, was used to transfect NCM460 cell lines, then stimulated with LPS. After LPS stimulation, cells were treated with chemically synthesized MDANP, and the essential proteins in the QRICH1 signalling pathway in cells were tested and compared. After the small-scale screening, a peptide (SKSKKFRRPDIQYPDATDED) named MDANP was determined as the principal peptide. Its protective effect against NEC through inhibiting the expression of ERS key proteins and impeding the intestinal cells' apoptosis was observed in the animal models. Furthermore, the inhibitive effect of MDANP on apoptosis of intestinal epithelial cells through modulating the PERK-eIF2ɑ-QRICH1 ERS pathway was also confirmed in vitro. Taken together, our data suggest that MDANP effectively ameliorates apoptosis in NEC through attenuating PERK-eIF2ɑ-QRICH1.


Subject(s)
Enterocolitis, Necrotizing , Infant, Newborn , Mice , Animals , Humans , Enterocolitis, Necrotizing/pathology , Lipopolysaccharides/pharmacology , Intestines/pathology , Cell Line , Peptides/pharmacology , Peptides/metabolism , Intestinal Mucosa/metabolism , Disease Models, Animal
9.
Acta Biomater ; 172: 423-440, 2023 12.
Article in English | MEDLINE | ID: mdl-37778486

ABSTRACT

Chemodynamic therapy (CDT) based on generating reactive oxygen species (ROS) is promising for cancer treatment. However, the intrinsic H2O2 is deficient for CDT, and glutathione (GSH) eliminates ROS to protect tumor cells from ROS cytotoxicity. Herein, we propose a strategy to switch the electron flow direction of GSH for O2 reduction and ROS generation rather than ROS clearance by using P(DA-Fc) nanoparticles, which are polymerized from ferrocenecarboxylic acid (Fc) coupled dopamine. P(DA-Fc) NPs with phenol-quinone conversion ability mimic NOX enzyme to deprive electrons from GSH to reduce O2 for H2O2 generation; the following •OH release can be triggered by Fc. Semiquinone radicals in P(DA-Fc) are significantly enhanced after GSH treatment, further demonstrated with strong single-electron reduction ability by calculation. In vitro and in vivo experiments indicate that P(DA-Fc) can consume intrinsic GSH to produce endogenous ROS; ROS generation strongly depends on GSH/pH level and eventually causes tumor cell death. Our work makes the first attempt to reverse the function of GSH from ROS scavenger to ROS producer, explores new roles of PDA-based nanomaterials in CDT beyond photothermal reagents and drug carriers, and provides a new strategy to improve the efficiency of CDT. STATEMENT OF SIGNIFICANCE: P(DA-Fc) nanoparticles performing tumor microenvironment response capacity and tumor reductive power utilize ability were fabricated for CDT tumor suppression. After endocytosis by tumor cells, P(DA-Fc) deprived GSH of electrons for H2O2 and •OH release, mimicking the intrinsic ROS production conducted by NADPH, further inducing tumor cell necrosis and apoptosis. Our work makes the first attempt to reverse the function of GSH from ROS scavenger to producer, explores new functions of PDA-based nanomaterials in CDT beyond photothermal reagents and drug carriers, and provides a new strategy to improve CDT efficiency.


Subject(s)
Nanoparticles , Neoplasms , Humans , Electrons , Reactive Oxygen Species , Polyphenols/pharmacology , Hydrogen Peroxide , Oxidation-Reduction , Drug Carriers , Cell Line, Tumor , Tumor Microenvironment , Glutathione , Neoplasms/drug therapy
10.
PeerJ ; 11: e16054, 2023.
Article in English | MEDLINE | ID: mdl-37744220

ABSTRACT

Objective: Thyroid cancer is the third most prevalent cancer among females. Genetic testing based on next-generation sequencing may provide an auxiliary diagnosis to reduce cytologically diagnostic uncertainty. However, commercial multigene tests are not widely available and are not well-tested in the Chinese population. Methods: In this study, we designed a multigene testing panel and evaluated its performance in 529 cytologically indeterminate thyroid nodules (Bethesda III, IV and V). The molecular data of the DNA mutations and RNA fusions of fine needle aspiration samples were reviewed in conjunction with a clinical diagnosis, pathological reports, and definitive surgery for retrospective analysis. Then, the molecular risk stratification was investigated for its accuracy in malignant risk prediction. Results: The overall combined consistency revealed substantial agreement (Kappa = 0.726) with the sensitivity, specificity, positive predictive value, and negative predictive values of 97.80%, 82.14%, 98.99%, and 67.65%, respectively. The most common aberration was BRAFV600E (82.59%), followed by NRAS mutants (4.07%), RET fusions (3.70%), and KRAS mutants (3.15%). Two cases (0.44%) were categorized into a high-risk group, 426 cases (94.67%) were categorized into a BRAF-like group with totally histopathologic papillary patterned tumors, and 22 cases (4.89%) were categorized into a RAS-like group with 14 papillary and eight follicular patterned tumors when the cohort concurrent aberrations were excluded. Potentially aggressive features may be related to concurrent molecular alterations of BRAFV600E with TERTQ302R, and AKT1L52R, NRASG12C, NRASQ61R, and CCDC6-RET fusions. Conclusions: This study provided a multigene panel for identifying benign nodules from cytologically indeterminate thyroid nodules to avoid unnecessary surgery. We provide further evidence for using molecular risk stratification as a promising predictor of disease outcomes. The results of this study may be limited by the extremely high prevalence of cancer in the cohort for clinical reference.


Subject(s)
Thyroid Neoplasms , Thyroid Nodule , Female , Humans , Thyroid Nodule/diagnosis , Proto-Oncogene Proteins B-raf , Retrospective Studies , Thyroid Neoplasms/diagnosis , Risk Assessment
11.
Altern Ther Health Med ; 29(8): 139-143, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37632946

ABSTRACT

Objective: The objective of this study was to construct and validate a nomogram for preoperatively identifying central lymph node metastasis (CLNM) in patients with papillary thyroid microcarcinoma (PTMC) using ultrasound imaging characteristics and the BRAF V600E gene mutation. Methods: A retrospective data analysis was conducted on 216 PTMC patients who underwent surgery at our facility between February 2016 and June 2022. Univariate and multivariate analyses examined the relationship between CLNM and clinicopathological traits, the BRAF V600E mutation, and ultrasound imaging characteristics. The area under the curve (AUC) was calculated, and receiver operating characteristic (ROC) curves were constructed to assess the predictive efficacy of the model in both the training and validation sets. Calibration curves were generated to evaluate the agreement between predicted and observed outcomes. Decision curve analysis (DCA) was performed to assess the clinical suitability of the model. A nomogram was developed to illustrate the predicted likelihood of CLNM. Results: The incidence rate of CLNM was found to be 38.4% (83/216 patients). Logistic univariate and multivariate analyses revealed that the BRAF V600E mutation, patient age less than 45 years, tumor size greater than 5 mm, thyroid capsule invasion, and presence of microcalcification in the tumor were independent risk factors for CLNM. The model demonstrated high exclusionary performance with AUC values of 0.88 and 0.877 in the training and validation cohorts, respectively. The calibration curve and DCA confirmed the accuracy of the predicted outcomes and the clinical value of the nomogram. Conclusions: A model incorporating ultrasound imaging characteristics and the BRAF V600E mutation can effectively predict the risk of central lymph node metastasis in patients with papillary thyroid microcarcinoma before surgery. The identified risk factors, including tumor size greater than 5 mm3, BRAF V600E mutation, patient age less than 45 years, nodule capsule invasion, and presence of microcalcification, can aid in surgical decision-making. The nomogram provides a valuable tool for clinicians to assess the likelihood of CLNM in PTMC patients.


Subject(s)
Calcinosis , Proto-Oncogene Proteins B-raf , Humans , Middle Aged , Proto-Oncogene Proteins B-raf/genetics , Nomograms , Retrospective Studies , Lymphatic Metastasis/diagnostic imaging , Risk Factors , Ultrasonography
12.
J Am Chem Soc ; 145(35): 19312-19320, 2023 Sep 06.
Article in English | MEDLINE | ID: mdl-37611205

ABSTRACT

The establishment of active sites as the frustrated Lewis pair (FLP) has recently attracted much attention ranging from homogeneous to heterogeneous systems in the field of catalysis. Their unquenched reactivity of Lewis acid and base pairs in close proximity that are unable to form stable adducts has been shown to activate small molecules such as dihydrogen heterolytically. Herein, we show that grafted Ru metal-organic framework-based catalysts prepared via N-containing linkers are rather catalytically inactive for H2 activation despite the application of elevated temperatures. However, upon light illumination, charge polarization of the anchored Ru bipyridine complex can form a transient Lewis acid-base pair, Ru+-N- via metal-to-ligand charge transfer, as confirmed by time-dependent density functional theory (TDDFT) calculations to carry out effective H2-D2 exchange. FTIR and 2-D NMR endorse the formation of such reactive intermediate(s) upon light irradiation.

13.
Transl Pediatr ; 12(4): 608-617, 2023 Apr 29.
Article in English | MEDLINE | ID: mdl-37181026

ABSTRACT

Background: The short-term and long-term severe complications of preterm infants have brought serious psychological and economic burdens to the society and family. Therefore, our study aimed to investigate the risk factors for the mortality and serious complications in very premature infants less than 32 weeks of gestational age (GA), so as to guide the antenatal and postnatal care of very premature. Methods: The very premature infants from 1 January 2019 to 31 December 2021 from 15 member hospitals of the Neonatal Intensive Care Unit (NICU) Multi-center Clinical Research Collaboration Group in Jiangsu Province were recruited. In accordance with the plan of the intensive care unit for unified management, recruitment of premature infants is carried out on the day of admission, and discharge or death is the outcome indicator in 1-2 months by telephone follow-up. The research content mainly includes three aspects: clinical information of mother and infant, outcomes and complications. According to the final outcomes, very premature infants were divided into two categories: survival without severe complications, survival with severe complications and death. Then, univariate and multivariate logistic regression model and receiver operating characteristic (ROC) analyses were used to analyze the independent risk factors. Results: A total of 3,200 very premature infants with GA less than 32 weeks were recruited. The median GA is 30.00 (28.57, 31.14) weeks, the average birth weight is 1,350 (1,110, 1,590) g, among whom 375 premature infants survived with severe complications, and 2,391 premature infants survived without severe complications. Then, it was found that GA at birth was a protective factor for death and severe complications, whereas severe neonatal asphyxia and persistent pulmonary hypertension of the newborn (PPHN) were independent risk factors for death and severe complications in very premature infants born at less than 32 weeks of gestation. Conclusions: The prognosis of very premature infants in NICU treatment depends not only on GA, but also on various perinatal factors and their clinical management, such as preterm asphyxia and PPHN occurrence, so the next step is necessary for multicenter continuous quality improvement to improve outcomes in very preterm infants.

14.
Water Environ Res ; 95(5): e10868, 2023 May.
Article in English | MEDLINE | ID: mdl-37072151

ABSTRACT

Bioflocculants have received more and more attention as alternatives to chemical flocculants because of their innocuousness, environmental friendliness, and high effectiveness. This study aims to investigate various factors that influence the performance of the novel bioflocculant produced by Bacillus thuringiensis (BF-TWB10) and analyze its adsorption kinetics to optimize its flocculation performance for real applications. The best-fit kinetic model was pseudo-second order with R2 = 0.999. The effects of pretreatment temperature, pH, and the presence of cations on flocculation were assessed. Further investigations of flocculation, including zeta potential analysis and particle size analysis, were also conducted. Thermal pretreatment of BF-TWB10 or the presence of divalent cations could stimulate the decolorization efficiency of the bioflocculant. BF-TWB10 manifested outstanding dye removal performances with over 90% for all tested anionic dyes at pH 2 and 3. Its decolorization efficiency on anionic dyes decreased with the increase of pH values. Zeta potential analysis revealed that the electrostatic repulsion between anionic dyes decreased after the addition of BT-TWB10 and further diminished by adjusting the reaction mixture to pH 2 before flocculation, suggesting the occurrence of adsorption bridging and charge neutralization. These findings proposed that BF-TWB10 might be a promising bioflocculant for the removal of dyes in textile wastewater. PRACTITIONER POINTS: Bioflocculant BF-TWB10 shows outstanding performance in flocculation. Adsorption process follows pseudo-second-order kinetic model. Flocculation process is pH-responsive. High-temperature pretreatment or divalent cations enhance its flocculation performance. The analyses suggest the occurrence of charge neutralization and adsorption bridging.


Subject(s)
Bacillus thuringiensis , Cations, Divalent , Flocculation , Kinetics , Coloring Agents , Hydrogen-Ion Concentration
15.
ACS Catal ; 13(2): 1207-1220, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36714055

ABSTRACT

The hydrogen-borrowing amination of alcohols is a promising route to produce amines. In this study, experimental parameters involved in the preparation of Pt/CeO2 catalysts were varied to assess how physicochemical properties influence their performance in such reactions. An amination reaction between cyclopentanol and cyclopentylamine was used as the model reaction for this study. The Pt precursor used in the catalyst synthesis and the properties of the CeO2 support were both found to strongly influence catalytic performance. Aberration corrected scanning transmission electron microscopy revealed that the most active catalyst comprised linearly structured Pt species. The formation of these features, a function result of epitaxial Pt deposition along the CeO2 [100] plane, appeared to be dependent on the properties of the CeO2 support and the Pt precursor used. Density functional theory calculations subsequently confirmed that these sites were more effective for cyclopentanol dehydrogenation-considered to be the rate-determining step of the process-than Pt clusters and nanoparticles. This study provides insights into the desirable catalytic properties required for hydrogen-borrowing amination but has relevance to other related fields. We consider that this study will provide a foundation for further study in this atom-efficient area of chemistry.

16.
Small Methods ; 7(3): e2201200, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36683207

ABSTRACT

Hydrogen (H) conductivity on oxide-based materials is crucially important in fuel cells and related catalysis. Here, this work measures the diffusion rate of H generated from Ru nanoparticles loaded on polar MgO(111) facet particles under H2 at elevated temperatures without moisture and compares it to conventional nonpolar MgO(110) for the first time by in situ quasielastic neutron scattering (QENS). The QENS reveals an exceptional diffusion rate on the polar facet via a proton (H+ ) hopping mechanism, which is an order of magnitude superior to that of typical H+ -conducting oxides. This work attributes this to the unique atomic arrangement of alternate layers of Mg cations and O anions of the polar MgO(111) where the strong electrostatic field of terminal oxygen anions facilitates protonic migration with a lower degree of local covalency.

17.
J Cancer Res Clin Oncol ; 149(1): 219-230, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36352148

ABSTRACT

PURPOSE: This study aimed to evaluate the effects of curcumin by co-administration of arsenic trioxide (As2O3) in acute myeloid leukemia (AML) treatment, using network pharmacology and experimental validation. METHODS: Using Pubchem database, Traditional Chinese Medicine Information Database (TCMID) database, and Swiss target prediction database to predict compound-related targets, AML-associated targets were determined using GeneCards and Online Mendelian Inheritance in Man (OMIM) databases. We identify overlapping common targets by comparing Compounds-related and AML-associated targets and using these targets to perform GO and KEGG functional enrichment analyses. Subsequently, these targets were input into the STRING database, and we used Cytoscape to construct protein-protein interaction (PPI) network. Finally, we used KG1-a cells and the AML mouse model to measure the anti-leukemia effects of curcumin and As2O3 and their combination. RESULTS: Compounds and targets screening hinted that 85 intersection targets were predicted in the curcumin treatment of AML, 75 targets in the As2O3 treatment of AML, and 48 targets in the curcumin combined with the As2O3 treatment of AML. GO and KEGG analyses indicated that the top 10 enriched biological processes and top 20 pathways implicated in the therapeutic effects of curcumin and As2O3 on AML, respectively. In addition, network pharmacology screening revealed STAT3, TP53, EP300, MAPK1, and PIK3CA as the top five genes in PPI network of curcumin treatment of AML and TP53, MAPK3, MAPK1, STAT3, and SRC as the top five genes in PPI network of As2O3 treatment of AML. Moreover, the in vitro experiment demonstrated that curcumin combined with As2O3 inhibited proliferation and induced apoptosis in KG1-a cells, and this effect is more substantial than curcumin or As2O3 alone. Mechanistically, the curcumin combined with As2O3 significantly down-regulated the protein expression of JAK2, STAT3, and Bcl-2, and up-regulated the levels of P53, P27, and Bax. In the mouse model, the survival time of mice in each administration group was drawn out to varying degrees, with the most significant prolongation in the curcumin combined with the As2O3 group. CONCLUSION: Our results suggested that curcumin and As2O3 combination therapy exerts more significant anti-leukemia effects in the treatment of AML than curcumin or As2O3 monotherapy by up-regulating p53 pathway and down-regulating the JAK2/STAT3 pathway.


Subject(s)
Curcumin , Drugs, Chinese Herbal , Leukemia, Myeloid, Acute , Animals , Mice , Arsenic Trioxide , Curcumin/pharmacology , Tumor Suppressor Protein p53/genetics , Network Pharmacology , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics
18.
J Am Chem Soc ; 144(51): 23340-23351, 2022 12 28.
Article in English | MEDLINE | ID: mdl-36512749

ABSTRACT

ZnO plays a very important role in many catalytic processes involving H2, yet the details on their interactions and H2 activation mechanism are still missing, owing to the lack of a characterization method that provides resolution at the atomic scale and follows the fate of oxide surface species. Here, we apply 17O solid-state NMR spectroscopy in combination with DFT calculations to unravel the surface structure of ZnO nanorods and explore the H2 activation process. We show that six different types of oxygen ions in the surface and subsurface of ZnO can be distinguished. H2 undergoes heterolytic dissociation on three-coordinated surface zinc and oxygen ions, while the formed hydride species migrate to nearby oxygen species, generating a second hydroxyl site. When oxygen vacancies are present, homolytic dissociation of H2 occurs and zinc hydride species form from the vacancies. Reaction mechanisms on oxide surfaces can be explored in a similar manner.


Subject(s)
Zinc Oxide , Catalysis , Oxides , Oxygen , Zinc
19.
Chem Sci ; 13(37): 11083-11090, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36320476

ABSTRACT

Determining the different surfaces of oxide nanocrystals is key in developing structure-property relations. In many cases, only surface geometry is considered while ignoring the influence of surroundings, such as ubiquitous water on the surface. Here we apply 17O solid-state NMR spectroscopy to explore the facet differences of morphology-controlled ceria nanocrystals considering both geometry and water adsorption. Tri-coordinated oxygen ions at the 1st layer of ceria (111), (110), and (100) facets exhibit distinct 17O NMR shifts at dry surfaces while these 17O NMR parameters vary in the presence of water, indicating its non-negligible effects on the oxide surface. Thus, the interaction between water and oxide surfaces and its impact on the chemical environment should be considered in future studies, and solid-state NMR spectroscopy is a sensitive approach for obtaining such information. The work provides new insights into elucidating the surface chemistry of oxide nanomaterials.

20.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(9): 988-993, 2022.
Article in Chinese | MEDLINE | ID: mdl-36111716

ABSTRACT

OBJECTIVES: To investigate the current status of antibiotic use in very low birth weight/extremely low birth weight infants in Jiangsu Province of China, and to provide a clinical basis for the quality and improvement of antibiotic management in the neonatal intensive care unit (NICU). METHODS: A retrospective analysis was performed on the data on general conditions and antibiotic use in the very low birth weight/extremely low birth weight infants who were admitted to 15 hospitals of Jiangsu Province from January 1, 2019 to December 31, 2020. A questionnaire containing 10 measures to reduce antibiotic use was designed to investigate the implementation of these intervention measures. RESULTS: A total of 1 920 very low birth weight/extremely low birth weight infants were enrolled, among whom 1 846 (96.15%) were treated with antibiotic, and the median antibiotic use rate (AUR) was 50/100 patient-days. The AUR ranged from 24/100 to 100/100 patient-days in the 15 hospitals. After adjustment for the confounding factors including gestational age, birth weight, and neonatal critical score, the Poisson regression analysis showed that there was a significant difference in the adjusted AUR (aAUR) among the hospitals (P<0.01). The investigation results showed that among the 10 measures to reduce antibiotic use, 8 measures were implemented in less than 50% of these hospitals, and the number of intervention measures implemented was negatively correlated with aAUR (rs=-0.564, P=0.029). CONCLUSIONS: There is a high AUR among the very low birth weight/extremely low birth weight infants in the 15 hospitals of Jiangsu Province, with a significant difference among hospitals. The hospitals implementing a relatively few measures to reduce antibiotic use tend to have a high AUR. It is expected to reduce AUR in very low birth weight/extremely low birth weight infants by promoting the quality improvement of antibiotic use management in the NICU.


Subject(s)
Anti-Bacterial Agents , Infant, Extremely Low Birth Weight , Anti-Bacterial Agents/therapeutic use , China , Hospitals , Humans , Infant , Infant, Newborn , Retrospective Studies , Surveys and Questionnaires
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