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1.
J Am Chem Soc ; 146(1): 1144-1152, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38164902

RESUMEN

It is crucial to achieve continuous production of highly concentrated and pure C2 chemicals through the electrochemical CO2 reduction reaction (eCO2RR) for artificial carbon cycling, yet it has remained unattainable until now. Despite one-pot tandem catalysis (dividing the eCO2RR to C2 into two catalytical reactions of CO2 to CO and CO to C2) offering the potential for significantly enhancing reaction efficiency, its mechanism remains unclear and its performance is unsatisfactory. Herein, we selected different CO2-to-CO catalysts and CO-to-acetate catalysts to construct several tandem catalytic systems for the eCO2RR to acetic acid. Among them, a tandem catalytic system comprising a covalent organic framework (PcNi-DMTP) and a metal-organic framework (MAF-2) as CO2-to-CO and CO-to-acetate catalysts, respectively, exhibited a faradaic efficiency of 51.2% with a current density of 410 mA cm-2 and an ultrahigh acetate yield rate of 2.72 mmol m-2 s-1 under neutral conditions. After electrolysis for 200 h, 1 cm-2 working electrode can continuously produce 20 mM acetic acid aqueous solution with a relative purity of 95+%. Comprehensive studies revealed that the performance of tandem catalysts is influenced not only by the CO supply-demand relationship and electron competition between the two catalytic processes in the one-pot tandem system but also by the performance of the CO-to-C2 catalyst under diluted CO conditions.

2.
Chem Commun (Camb) ; 60(27): 3669-3672, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38456336

RESUMEN

It is important and challenging to utilise CO2 and NO3- as a feedstock for electrosynthesis of urea. Herein, we reported a stable 2D metal-organic framework (MOF) Cu-HATNA, possessing planar CuO4 active sites, as an efficient electrocatalyst for coupling CO2 and NO3- into urea, achieving a high yield rate of 1.46 g h-1 gcat-1 with a current density of 44.2 mA cm-1 at -0.6 V vs. RHE. This performance surpasses most of the previously reported catalysts, revealing the great prospects of MOFs in sustainable urea synthesis.

3.
Huan Jing Ke Xue ; 45(3): 1674-1683, 2024 Mar 08.
Artículo en Zh | MEDLINE | ID: mdl-38471879

RESUMEN

Carbon, nitrogen, phosphorus, and potassium in the soil are the necessary nutrient elements for plant growth, and their contents and ecological stoichiometry can reflect the status of soil quality and nutrient limitation. The Huayuankou Yellow River Floating Bridge Wetland in the lower Yellow River was selected as the research object. The methods of ANOVA, redundancy analysis, and linear regression fitting were used to study the contents of organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), alkaline nitrogen (AN), available phosphorus (AP), available potassium (AK), and their ecological stoichiometric ratios as well as the limiting elements of soil nutrients, and the key physicochemical properties that affect soil nutrients and their ecological stoichiometry in the wetland were revealed. The results showed that the mean values of ω(SOC), ω(TN), ω(TP), ω(TK), ω(AN), ω(AP), and ω(AK) in wetland soil were 5.46 g·kg-1, 0.60 g·kg-1, 0.28 g·kg-1, 17.06 g·kg-1, 13.75 mg·kg-1, 6.54 mg·kg-1, and 158.56 mg·kg-1, respectively, which showed an increasing trend from the river bank to the shoaly land and were generally higher at the high vegetation coverage areas than at the low vegetation coverage areas. There were significant correlations among SOC, TN, TP, and TK. Soil C/P, C/K, N/P, and N/K showed a consistent trend with soil nutrients, whereas C/N showed the opposite. The coefficients of variation of SOC, TN, AN, N/P, and N/K in the soil exceeded 50.00%, with significant spatial differences. The average value of C/N in wetland soil was 11.882, which was close to the average level of soils in China, whereas the average values of C/P and N/P were 49.119 and 4.516, respectively, both of which were lower than the average level of soils in China, and the N/P of soil was far less than 14, which indicated that N was limited in the soil. The proportion of clay and electrical conductivity combined to explain 61.4% and 43.9% of the variation in the soil nutrients and their ecological stoichiometry, respectively, which were the dominant soil physicochemical properties affecting the soil nutrients and their ecological stoichiometry of Huayuankou Yellow River Floating Bridge Wetland. The research results are helpful to improve our knowledge of nutrients and their influencing factors in the wetland soil of the lower Yellow River and provide an important scientific basis for the ecological restoration and management of the wetland in the lower Yellow River.

4.
Autoimmun Rev ; 23(5): 103538, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38556034

RESUMEN

OBJECTIVE: This study aimed to analyse existing research on systemic sclerosis (SSc) conducted over the past 73 years to develop an essential reference for a comprehensive and objective understanding of this field of inquiry. METHODS: Using the Web of Science Core Collection, PubMed, and Scopus databases as data sources for the bibliometric analysis, we searched for published literature related to SSc over the past 73 years. The Bibliometrix package was used to analyse key bibliometric indicators, such as annual publication volume, countries, journals, author contributions, and research hotspots. RESULTS: From 1970 to 2022, the number of SSc articles steadily increased, reaching its peak in 2020-2022, with approximately 1200 papers published in each of these three years. Matucci-Cerinic et al.'s team published the most articles (425). The United States (11,282), Italy (7027), and France (5226) were the most predominant contexts. The most influential scholars in the field were Denton, Leroy, Steen, and Khanna, with H-indices of 86, 84, and 83, respectively. Arthritis and Rheumatism was the most influential journal in this field (H-index 142). High-frequency keywords in the SSc field included fibrosis (738), inflammation (242), vasculopathy (145), fibroblasts (120), and autoantibodies (118) with respect to pathogenesis, and interstitial lung disease (ILD, 708), pulmonary arterial hypertension (PAH, 696), and Raynaud's phenomenon (326) with regards to clinical manifestations. CONCLUSION: In the past three years, SSc research has entered a period of rapid development, mainly driven by research institutions in Europe and the United States. The most influential journal has been Arthritis and Rheumatism, and autoimmune aspects, vasculopathy, fibrogenesis, PAH, and ILD remain the focus of current research and indicate trends in future research.


Asunto(s)
Bibliometría , Esclerodermia Sistémica , Humanos , Investigación Biomédica/tendencias , Investigación Biomédica/historia , Historia del Siglo XXI
5.
Medicine (Baltimore) ; 103(20): e38001, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758850

RESUMEN

To identify disease signature genes associated with immune infiltration in nonalcoholic steatohepatitis (NASH), we downloaded 2 publicly available gene expression profiles, GSE164760 and GSE37031, from the gene expression omnibus database. These profiles represent human NASH and control samples and were used for differential genes (DEGs) expression screening. Two machine learning methods, the Least Absolute Shrinkage and Selection Operator regression model and Support Vector Machine Recursive Feature Elimination, were used to identify candidate disease signature genes. The CIBERSORT deconvolution algorithm was employed to analyze the infiltration of 22 immune cell types in NASH. Additionally, we constructed a NASH cell model using HepG2 cells treated with oleic acid and free fatty acids. The construction of the cell model was verified using oil red O staining, and Western blotting was used to detect the protein expression of the disease signature genes in both control and model groups. As a result, a total of 262 DEGs were identified. These DEGs were primarily associated with metal ion transmembrane transporter activity, sodium ion transmembrane transporter protein activity, calcium ion, and neuroactive ligand-receptor interactions. FOS, IGFBP2, dual-specificity phosphatase 1 (DUSP1), and IKZF3 were identified as disease signature genes of NASH by the least absolute shrinkage and selection operator and Support Vector Machine Recursive Feature Elimination algorithms for DEGs analysis. The receiver operating characteristic curves showed that FOS, IGFBP2, DUSP1, and IKZF3 had good diagnostic value (area under receiver operating characteristic curve > 0.8). These findings were validated in the GSE89632 dataset and through cellular assays. Immunocyte infiltration analysis revealed that NASH was associated with CD8 T cells, CD4 T cells, follicular helper T cells, resting NK cells, eosinophils, regulatory T cells, and γδ T cells. The FOS, IGFBP2, DUSP1, and IKZF3 genes were specifically associated with follicular helper T cells. Lipid droplet aggregation significantly increased in HepG2 cells treated with oleic acid and free fatty acids, indicating successful construction of the cell model. In this model, the expression of FOS, IGFBP2, and DUSP1 was significantly decreased, while that of IKZF3 was significantly elevated (P < .01, P < .001) compared with the control group. Therefore, FOS, IGFBP2, DUSP1, and IKZF3 can be considered as disease signature genes associated with immune infiltration in NASH.


Asunto(s)
Aprendizaje Automático , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/inmunología , Células Hep G2 , Perfilación de la Expresión Génica/métodos , Algoritmos , Máquina de Vectores de Soporte , Transcriptoma
6.
Chin J Integr Med ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753274

RESUMEN

OBJECTIVE: To study the effect of Shexiang Tongxin Dropping Pill (STDP) on angiogenesis in diabetic cardiomyopathy mice with coronary microcirculation dysfunction (CMD). METHODS: According to a random number table, 6 of 36 SPF male C57BL/6 mice were randomly selected as the control group, and the remaining 30 mice were injected with streptozotocin intraperitoneally to replicate the type 1 diabetes model. Mice successfully copied the diabetes model were randomly divided into the model group, STDP low-dose group [15 mg/(kg·d)], medium-dose group [30 mg/(kg·d)], high-dose group [60 mg/(kg·d)], and nicorandil group [15 mg/(kg·d)], 6 in each group. The drug was given by continuous gavage for 12 weeks. The cardiac function of mice in each group was detected at the end of the experiment, and coronary flow reserve (CFR) was detected by chest Doppler technique. Pathological changes of myocardium were observed by hematoxylin-eosin staining, collagen fiber deposition was detected by masson staining, the number of myocardial capillaries was detected by platelet endothelial cell adhesion molecule-1 staining, and the degree of myocardial hypertrophy was detected by wheat germ agglutinin staining. The expression of the vascular endothlial growth factor (VEGF)/endothelial nitric oxide synthase (eNOS) signaling pathway-related proteins in myocardial tissue was detected by Western blot. RESULTS: Compared with the model group, medium- and high-dose STDP significantly increased the left ventricular ejection fraction and left ventricular fraction shortening (P<0.01), obviously repaired the disordered cardiac muscle structure, reduced myocardial fibrosis, reduced myocardial cell area, increased capillary density, and increased CFR level (all P<0.01). Western blot showed that high-dose STDP could significantly increase the expression of VEGF and promote the phosphorylation of vascular endothelial growth factor receptor 2, phosphoinositide 3-kinase, protein kinase B, and eNOS (P<0.05 or P<0.01). CONCLUSION: STDP has a definite therapeutic effect on diabetic CMD, and its mechanism may be related to promoting angiogenesis through the VEGF/eNOS signaling pathway.

7.
World J Psychiatry ; 14(5): 742-759, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38808081

RESUMEN

BACKGROUND: Despite advances in research on psychopathology and social media use, no comprehensive review has examined published papers on this type of research and considered how it was affected by the coronavirus disease 2019 (COVID-19) outbreak. AIM: To explore the status of research on psychopathology and social media use before and after the COVID-19 outbreak. METHODS: We used Bibliometrix (an R software package) to conduct a scientometric analysis of 4588 relevant studies drawn from the Web of Science Core Collection, PubMed, and Scopus databases. RESULTS: Such research output was scarce before COVID-19, but exploded after the pandemic with the publication of a number of high-impact articles. Key authors and institutions, located primarily in developed countries, maintained their core positions, largely uninfluenced by COVID-19; however, research production and collaboration in developing countries increased significantly after COVID-19. Through the analysis of keywords, we identified commonly used methods in this field, together with specific populations, psychopathological conditions, and clinical treatments. Researchers have devoted increasing attention to gender differences in psychopathological states and linked COVID-19 strongly to depression, with depression detection becoming a new trend. Developments in research on psychopathology and social media use are unbalanced and uncoordinated across countries/regions, and more in-depth clinical studies should be conducted in the future. CONCLUSION: After COVID-19, there was an increased level of concern about mental health issues and a changing emphasis on social media use and the impact of public health emergencies.

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