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1.
Gene ; 932: 148896, 2025 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-39209183

RESUMEN

Pescadillo ribosomal biogenesis factor 1 (PES1), a nucleolar protein initially identified in zebrafish, plays an important role in embryonic development and ribosomal biogenesis. Notably, PES1 has been found to be overexpressed in a number of cancer types, where it contributes to tumorigenesis and cancer progression by promoting cell proliferation, suppressing cellular senescence, modulating the tumor microenvironment (TME) and promoting drug resistance in cancer cells. Moreover, recent emerging evidence suggests that PES1 expression is significantly elevated in the livers of Type 2 diabetes mellitus (T2DM) and obese patients, indicating its involvement in the pathogenesis of metabolic diseases through lipid metabolism regulation. In this review, we present the structural characteristics and biological functions of PES1, as well as complexes in which PES1 participates. Furthermore, we comprehensively summarize the multifaceted role of PES1 in various diseases and the latest insights into its underlying molecular mechanisms. Finally, we discuss the potential clinical translational perspectives of targeting PES1, highlighting its promising as a therapeutic intervention and treatment target.


Asunto(s)
Neoplasias , Proteínas de Unión al ARN , Humanos , Animales , Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Microambiente Tumoral , Metabolismo de los Lípidos , Terapia Molecular Dirigida/métodos , Obesidad/metabolismo , Obesidad/genética
2.
Thromb J ; 22(1): 87, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39367466

RESUMEN

BACKGROUND: The association between uric acid and pulmonary embolism(PE) remains controversial, and there has been limited investigation into how uric acid influences pulmonary embolism across different age groups. Our study aimed to elucidate the relationship between uric acid levels and pulmonary embolism, considering variations across age groups. METHODS: A total of 368 patients who underwent computed tomography pulmonary angiography from July 2018 to May 2022 were included in the analysis. Subsequently, the cohort was stratified by age, with separate univariate and multivariate logistic regression analyses conducted for the elderly (aged ≥ 60 years) and non-elderly (aged < 60 years), respectively. RESULTS: The study revealed that patients with PE exhibited higher uric acid levels compared to those without (325.11 ± 137.02 vs. 298.26 ± 110.54 (umol/l), p = 0.039). This disparity persisted even after adjusting for multiple confounders (OR = 1.002, 95% CI 1.000-1.005, p = 0.042). Additionally, a notable age difference was observed between PE and non-PE patients (65.7 ± 16.12 vs. 61.42 ± 15.03 (umol/l), p = 0.009). Subsequently, upon age stratification, significant differences (p < 0.05) in serum uric acid were noted between PE and non-PE patients in both elderly and non-elderly populations. However, elevated uric acid levels were independently associated with PE only in the elderly following adjustment for multiple confounders (OR = 1.003, 95% CI 1.001-1.005, p = 0.008). CONCLUSION: High uric acid levels are an independent risk factor for pulmonary embolism in the elderly (≥ 60 years).

3.
Entropy (Basel) ; 26(9)2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39330139

RESUMEN

The fault diagnosis on a transmission line based on the characteristics of the power spectral entropy is proposed in this article. The data preprocessing for the experimental measurement is also introduced using the EEMD. The EEMD is used to preprocess experimental measurements, which are nonlinear and non-stationary fault signals, to overcome the mode mixing. This study focuses on the fault location detection of transmission lines during faults. The proposed method is adopted for different fault types through simulation under the fault point by collecting current and voltage signals at a distance from the fault point. An analysis and comprehensive evaluation of three-phase measured current and voltage signals at distinct fault locations is conducted. The form and position of the fault are distinguished directly and effectively, thereby significantly improving the transmission line efficiency and accuracy of fault diagnosis.

4.
Front Neurol ; 15: 1484618, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39318873

RESUMEN

[This corrects the article DOI: 10.3389/fneur.2024.1371375.].

5.
Int J Mol Sci ; 25(17)2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39273190

RESUMEN

Breast and ovarian cancers pose significant therapeutic challenges. We explored the synergistic cytotoxicity of histone deacetylase inhibitors (HDACis), poly(ADP-ribose) polymerase inhibitors (PARPis), and decitabine in breast (MDA-MB-231 and MCF-7) and ovarian (HEY-T30 and SKOV-3) cancer cell lines that were exposed to HDACi (panobinostat or vorinostat), PARPi (talazoparib or olaparib), decitabine, or their combinations. HDACi, PARPi, and decitabine combinations had synergistic cytotoxicity (assessed by MTT and clonogenic assays) in all cell lines (combination index < 1). Clonogenic assays confirmed the sensitivity of breast and ovarian cancer cell lines to the three-drug combinations (panobinostat, talazoparib, and decitabine; panobinostat, olaparib, and decitabine; vorinostat, talazoparib, and decitabine; vorinostat, olaparib, and decitabine). Cell proliferation was inhibited by 48-70%, and Annexin V positivity was 42-59% in all cell lines exposed to the three-drug combinations. Western blot analysis showed protein PARylation inhibition, caspase 3 and PARP1 cleavage, and c-MYC down-regulation. The three-drug combinations induced more DNA damage (increased phosphorylation of histone 2AX) than the individual drugs, impaired the DNA repair pathways, and altered the epigenetic regulation of gene expression. These results indicate that HDACi, PARPi, and decitabine combinations should be further explored in these tumor types. Further clinical validation is warranted to assess their safety and efficacy.


Asunto(s)
Neoplasias de la Mama , Proliferación Celular , Decitabina , Sinergismo Farmacológico , Inhibidores de Histona Desacetilasas , Neoplasias Ováricas , Ftalazinas , Piperazinas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Humanos , Decitabina/farmacología , Femenino , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Ftalazinas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Línea Celular Tumoral , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Proliferación Celular/efectos de los fármacos , Piperazinas/farmacología , Vorinostat/farmacología , Panobinostat/farmacología , Apoptosis/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Ácidos Hidroxámicos/farmacología , Células MCF-7
6.
BMC Pediatr ; 24(1): 600, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39306664

RESUMEN

BACKGROUND: An increased incidence of brain abscesses was observed post-COVID-19 pandemic. However, it remains unclear how the COVID-19 pandemic influenced the epidemiology of brain abscesses. This study aimed to investigate changes in the epidemiology of brain abscesses pre- and post-COVID-19 pandemic. METHODS: A retrospective study of demographic, clinical, radiological, and laboratory characteristics of patients with brain abscesses in Children's Hospital of Soochow University from 2015-2023 was performed. RESULTS: A total of 34 patients were admitted to the hospital during the study. The post-COVID-19 cohort had an average of 5.5 cases/year, which is a 129.2% increase compared to the pre-COVID-19 cohort's average of 2.4 cases/year. Additionally, the rates of fever upon admission (86.36% vs 50%, p = 0.04) and experiencing high-grade fever within 6 weeks before admission (40.91% vs 8.33%, p = 0.044) were significantly increased. A potential rise in the rate of intensive care unit admission was observed (36.36% vs 8.33%, p = 0.113). The average value of globulin in the post-COVID cohort was significantly higher compared to the pre-COVID cohort (31.60 ± 5.97 vs 25.50 ± 5.08, p = 0.009). Streptococcal infections were the predominant cause of brain abscesses in both cohorts (40% vs 43.75%, p = 0.57). CONCLUSIONS: There was a significant increase in the number of brain abscess patients after the COVID-19 pandemic. This underscores the importance of children receiving the streptococcal vaccine.


Asunto(s)
Absceso Encefálico , COVID-19 , Humanos , COVID-19/epidemiología , Absceso Encefálico/epidemiología , Estudios Retrospectivos , Niño , Femenino , Masculino , Preescolar , Lactante , Adolescente , Incidencia , China/epidemiología , Hospitalización/estadística & datos numéricos , SARS-CoV-2
7.
Acta Cardiol Sin ; 40(5): 635-643, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39308657

RESUMEN

Objectives: Cardiac amyloidosis (CA) is a type of systemic amyloidosis. Amyloid-targeting positron emission tomography (PET) has shown potential as an imaging method for CA. However, the optimal imaging protocol and role of 18F-florbetaben (FBB) PET in the diagnosis and subtyping of CA have yet to be determined. Methods: Patients with suspected CA who had positive or equivocal results of technetium-99m pyrophosphate (PYP) scintigraphy were enrolled for dynamic and late FBB PET imaging. In addition to visual assessment, a kinetic modeling-based approach including target-to-background ratio (TBR) and myocardial retention fraction (RF) of serial images reconstructed from a 20-min dynamic acquisition, and a late image at 110 min post-injection were performed. We compared FBB PET measures of four typical patients with light chain amyloidosis (AL), wild-type transthyretin amyloidosis (ATTRwt), variant transthyretin amyloidosis (ATTRv), and heart failure, respectively. We also reviewed the literature on the clinical use of amyloid PET in CA. Results: Myocardial tracer retention was only found in the AL patient on the late images. TBR and RF were highest in the AL patient followed by the ATTRwt patient, and lowest in the ATTRv and non-CA patients. Conclusions: FBB PET has potential in the detection and non-invasive subtyping of CA, especially in subjects with equivocal PYP findings or monoclonal gammopathy.

8.
Int J Biol Macromol ; : 135228, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233158

RESUMEN

The shell of Hermetia illucens L. contains considerable amounts of chitin, which has various biological activities. So far, few studies have focused on chitin of Hermetia illucens L. as a source of chitosan and oligosaccharides. There is great potential for utilizing Hermetia illucens L. chitin to produce chitosan films in biomaterials. We studied different extraction conditions for chitin and extracted it from black soldier fly (BSF) (Hermetia illucens L.). Three processing steps were adopted: (1) demineralization, (2) deproteinization, and (3) decolorization. The chemical components (moisture, ash, protein, fat, residual protein, and residual mineral contents) and physicochemical characteristics of the chitin and chitosan extracted under these three conditions were determined. In addition, Fourier transform infrared spectroscopy and X-ray diffraction were used to analyze the extracted chitin and commercial samples, and the results showed that demineralization-deproteinization-decolorization treatments could achieve the highest chitin yield (7.18 ±â€¯0.11 %), chitosan yield (64.22 ±â€¯0.79 %), and the best purity (residual protein 0.56 ±â€¯0.01 % and residual ash 0.58 ±â€¯0.04 %), making it the best treatment method. Using this method, the residues produced from farmed BSF can be recycled and used as a new source of chitin.

9.
Nano Lett ; 24(35): 10883-10891, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39172995

RESUMEN

The development of electronic skin (e-skin) emulating the human skin's three essential functions (perception, protection, and thermoregulation) has great potential for human-machine interfaces and intelligent robotics. However, existing studies mainly focus on perception. This study presents a novel, eco-friendly, mechanically robust e-skin replicating human skin's three essential functions. The e-skin is composed of Ti3C2Tx MXene, polypyrrole, and bacterial cellulose nanofibers, where the MXene nanoflakes form the matrix, the bacterial cellulose nanofibers act as the filler, and the polypyrrole serves as a conductive "cross-linker". This design allows customization of the electrical conductivity, microarchitecture, and mechanical properties, integrating sensing (perception), EMI shielding (protection), and thermal management (thermoregulation). The optimal e-skin can effectively sense various motions (including minuscule artery pulses), achieve an EMI shielding efficiency of 63.32 dB at 78 µm thickness, and regulate temperature up to 129 °C in 30 s at 2.4 V, demonstrating its potential for smart robotics in complex scenarios.


Asunto(s)
Conductividad Eléctrica , Polímeros , Dispositivos Electrónicos Vestibles , Humanos , Polímeros/química , Pirroles/química , Nanofibras/química , Celulosa/química , Piel/química , Regulación de la Temperatura Corporal , Titanio/química , Robótica
10.
Poult Sci ; 103(10): 104064, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39106704

RESUMEN

Coccidiosis, caused by a protozoan parasite of the genus Eimeria, is one of the most severe contagious parasite diseases affecting the poultry industry worldwide. Using phytogenics to prevent chicken coccidiosis is a strategy aimed at combating the increasing issue of drug-resistant strains of Eimeria spp. This study demonstrates the anticoccidial activities of a medicinal herb, Trifolium pratense (TP) powder, and its ethanolic extract (designated TPE) against Eimeria spp. TPE exhibited significant suppressive activity against E. maxima oocyst sporulation and E. tenella sporozoite invasion and reproduction in Madin-Darby bovine kidney cells. Furthermore, administration of basal chicken diets containing TP powder or TPE to Eimeria-infected chickens significantly reduced the output of oocysts and severity of intestinal lesions. Dietary supplementation with TP significantly improved relative weight gain in E. tenella- and E. acervulina-infected chickens, while there was no significant improvement in E. maxima-infected chickens. The anticoccidial activities of TP and TPE on E. acervulina, E. tenella and E. maxima were further supported by anticoccidial index scores, which showed greater efficacy than those of amprolium, a commercial coccidiostat used in poultry. TP supplementation positively impacted the primary metabolism of chickens challenged with E. tenella or E. acervulina. The chemical fingerprints of TPE were established using liquid column chromatography; TPE contained 4 major compounds: ononin, sissotrin, formononetin, and biochanin A. In addition, various spectrometric methods were used to ensure the batch-to-batch consistency of TP/TPE. In conclusion, T. pratense is demonstrated to be a novel phytogenic supplement that can be used to control Eimeria-induced coccidiosis in chickens.


Asunto(s)
Coccidiosis , Coccidiostáticos , Extractos Vegetales , Enfermedades de las Aves de Corral , Trifolium , Trifolium/química , Suplementos Dietéticos , Coccidiostáticos/administración & dosificación , Coccidiostáticos/química , Coccidiostáticos/farmacología , Eimeria/efectos de los fármacos , Coccidiosis/tratamiento farmacológico , Coccidiosis/veterinaria , Pollos , Animales , Enfermedades de las Aves de Corral/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Extractos Vegetales/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Masculino , Intestinos/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos
11.
Front Neurol ; 15: 1371375, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39131052

RESUMEN

Background: Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive disease associated with lipid metabolic disorders. Because of its clinical diversity and rarity, the diagnosis is often unclear. However, there is still a lack of reports on bibliometric analysis of CTX. The aim of this study was to assess the progress and research developments of CTX over the past three decades, identify emerging trends, and establish novel directions for future research. Methods: The eligible literature were screened from the Web of Science Core Collection (WoSCC) database. The annual publication, countries, institutions, authors, journals, keywords and references were visually analyzed by Microsoft Excel 2019, CiteSpace 6.2.R4, VOSviewer 1.6.18 and online bibliometrics website (https://bibliometric.com/). Results: A total of 561 publications from WoSCC were included in this study. The United States is the country with the largest number of publications, and Karolinska Institutet is the institution with the largest number of publications. Björkhem I. ranks as the most published and cited author in the last three decades. Journal of Lipid Research is the most widely published and cited journal. The strongest burst of keywords is "diagnosis." Conclusion: Unraveling the pathogenesis of CTX and improving its diagnosis and treatment continue to be critical challenges that require urgent attention. Future research endeavors will be centered on enhancing the efficiency and accuracy of early diagnosis and intervention.

12.
Nucleic Acids Res ; 52(17): 10717-10729, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39189451

RESUMEN

African swine fever virus (ASFV) is one of the most important causative agents of animal diseases and can cause highly fatal diseases in swine. ASFV DNA polymerase (DNAPol) is responsible for genome replication and highly conserved in all viral genotypes showing an ideal target for drug development. Here, we systematically determined the structures of ASFV DNAPol in apo, replicating and editing states. Structural analysis revealed that ASFV DNAPol had a classical right-handed structure and showed the highest similarity to the structure of human polymerase delta. Intriguingly, ASFV DNAPol has a much longer fingers subdomain, and the thumb and palm subdomain form a unique interaction that has never been seen. Mutagenesis work revealed that the loss of this unique interaction decreased the enzymatic activity. We also found that the ß-hairpin of ASFV DNAPol is located below the template strand in the editing state, which is different from the editing structures of other known B family DNAPols with the ß-hairpin above the template strand. It suggests that B family DNAPols have evolved two ways to facilitate the dsDNA unwinding during the transition from replicating into editing state. These findings figured out the working mechanism of ASFV DNAPol and will provide a critical structural basis for the development of antiviral drugs.


Asunto(s)
Virus de la Fiebre Porcina Africana , Microscopía por Crioelectrón , ADN Polimerasa Dirigida por ADN , Modelos Moleculares , Virus de la Fiebre Porcina Africana/enzimología , Virus de la Fiebre Porcina Africana/genética , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Animales , Porcinos , Proteínas Virales/química , Proteínas Virales/metabolismo , Proteínas Virales/genética , Fiebre Porcina Africana/virología , Secuencia de Aminoácidos
13.
Small ; : e2402564, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087370

RESUMEN

For materials with coexisting phases, the transition from a random to an ordered distribution of materials often generates new mechanisms. Although the magnetic confinement effect has improved the electromagnetic (EM) performance, the transition from random to ordered magnetic confinement positions remains a synthetic challenge, and the underlying mechanisms are still unclear. Herein, precise control of magnetic nanoparticles is achieved through a spatial confinement growth strategy, preparing five different modalities of magnetic confined carbon fiber materials, effectively inhibiting magnetic agglomeration. Systematic studies have shown that the magnetic confinement network can refine CoNi NPs size and enhance strong magnetic coupling interactions. Compared to CoNi@HCNFs on the hollow carbon fibers (HCNFs) outer surface, HCNFs@CoNi constructed on the inner surface induce stronger spatial charge polarization relaxation at the interface and exhibit stronger magnetic coupling interactions at the inner surface due to the high-density magnetic coupling units at the micro/nanoscale, thereby respectively enhancing dielectric and magnetic losses. Remarkably, they achieve a minimum reflection loss (RLmin) of -64.54 dB and an absorption bandwidth of 5.60 GHz at a thickness of 1.77 mm. This work reveals the microscale mechanism of magnetic confinement-induced different polarization relaxation and magnetic response, providing a new strategy for designing magnetic materials.

14.
Int J Mol Sci ; 25(15)2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39126086

RESUMEN

Strigolactones (SLs) are plant hormones that regulate diverse developmental processes and environmental responses in plants. It has been discovered that SLs play an important role in regulating plant immune resistance to pathogens but there are currently no reports on their role in the interaction between Nicotiana benthamiana and the tobacco mosaic virus (TMV). In this study, the exogenous application of SLs weakened the resistance of N. benthamiana to TMV, promoting TMV infection, whereas the exogenous application of Tis108, a SL inhibitor, resulted in the opposite effect. Virus-induced gene silencing (VIGS) inhibition of two key SL synthesis enzyme genes, NtCCD7 and NtCCD8, enhanced the resistance of N. benthamiana to TMV. Additionally, we conducted a screening of N. benthamiana related to TMV infection. TMV-infected plants treated with SLs were compared to the control by using RNA-seq. The KEGG enrichment analysis and weighted gene co-expression network analysis (WGCNA) of differentially expressed genes (DEGs) suggested that plant hormone signaling transduction may play a significant role in the SL-TMV-N. benthamiana interactions. This study reveals new functions of SLs in regulating plant immunity and provides a reference for controlling TMV diseases in production.


Asunto(s)
Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Lactonas , Nicotiana , Enfermedades de las Plantas , Virus del Mosaico del Tabaco , Nicotiana/virología , Nicotiana/genética , Nicotiana/inmunología , Virus del Mosaico del Tabaco/fisiología , Lactonas/farmacología , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/virología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Inmunidad de la Planta/genética , Inmunidad de la Planta/efectos de los fármacos , Silenciador del Gen
15.
Zhonghua Nan Ke Xue ; 30(3): 241-248, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-39177391

RESUMEN

OBJECTIVE: To explore the potential action mechanism of Huotu Jiji Pellets (HJP) in the treatment of erectile dysfunction (ED) based on network pharmacology and molecular docking. METHODS: We identified the main effective compounds and active molecular targets of HJP from the database of Traditional Chinese Medicine Systems Pharmacology (TCMSP) and Integrative Pharmacology-Based Research Platform of Traditional Chinese Medicine (TCMIP) and the therapeutic target genes of ED from the databases of Genecards. Then we obtained the common targets of HJP and ED using the Venny software, constructed a protein-protein interaction (PPI) network of HJP acting on ED, and screened out the core targets with the Cytoscape software. Lastly we performed GO functional enrichment and KEGG pathway enrichment analyses of the core targets followed by molecular docking of HJP and the core targets using Chem3D and AutoDock Tools and QuickVina-W software. RESULTS: A total of 64 effective compounds, 822 drug-related targets, 1 783 disease-related targets and 320 common targets were obtained in this study. PPI network analysis showed that the core targets of HJP for ED included ESR1, HSP90AA1, SRC, and STAT3. GO functional enrichment analysis indicated the involvement of the core targets in such biological processes as response to xenobiotic stimulus, positive regulation of kinase activity, and positive regulation of MAPK cascade. KEGG pathway enrichment analysis suggested that PI3K-Akt, apoptosis, MAPK, HIF-1, VEGF, autophagy and other signaling pathways may be related to the mechanism of HJP acting on ED. Molecular docking prediction exhibited a good docking activity of the key active molecules of HJP with the core targets. CONCLUSION: This study showed that HJP acted on ED through multi-components, multi-targets and multi-pathways, which has provided some evidence and reference for the clinical treatment and subsequent studies of the disease.


Asunto(s)
Medicamentos Herbarios Chinos , Disfunción Eréctil , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Farmacología en Red , Mapas de Interacción de Proteínas , Masculino , Disfunción Eréctil/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Humanos , Transducción de Señal
16.
Sci Total Environ ; 951: 175290, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39117234

RESUMEN

Ozone (O3) pollution is a severe environmental problem in China. The incomplete understanding of atmospheric photochemical reaction mechanisms prevents us from accurately understanding the chemistry of O3 production. Here, we used an improved dual-channel reaction chamber technique to measure net photochemical O3 production rate (P(O3)net) directly in Dongguan, a typical industrial city in China. The maximum P(O3)net was 46.3 ppbv h-1 during the observation period, which is at a relatively high level compared to previous observations under different environment worldwide. We employed an observation-based box model coupled with the state-of-the-art atmospheric chemical mechanism (MCM v3.3.1) to investigate the chemistry of O3 production. Under the base scenario, the modelling underestimates P(O3)net by ~30 %. Additionally considering HO2 uptake by ambient aerosols, inorganic deposition, and Cl chemistry only caused a small change (< 13 %) in the simulation of P(O3)net. Further analysis indicates that unmeasured reactive volatile organic compounds (VOCs), such as oxygenated VOCs and branched alkenes are potential contributors to the underestimation of P(O3)net. This study underscores the underestimation of P(O3)net in conventional atmospheric modelling setups, providing a crucial scientific foundation for further investigation aimed at promoting our understanding of photochemical O3 formation.

17.
Nat Commun ; 15(1): 6138, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033166

RESUMEN

Integration of functional fillers into liquid metals (LM) induces rheology modification, enabling the free-form shaping of LM at the micrometer scale. However, integrating non-chemically modified low-dimensional materials with LM to form stable and uniform dispersions remain a great challenge. Herein, we propose a solvent-assisted dispersion (SAD) method that utilizes the fragmentation and reintegration of LM in volatile solvents to engulf and disperse fillers. This method successfully integrates MXene uniformly into LM, achieving better internal connectivity than the conventional dry powder mixing (DPM) method. Consequently, the MXene/LM (MLM) coating exhibits high electromagnetic interference (EMI) shielding performance (105 dB at 20 µm, which is 1.6 times that of coatings prepared by DPM). Moreover, the rheological characteristic of MLM render it malleable and facilitates direct printing and adaptation to diverse structures. This study offers a convenient method for assembling LM with low-dimensional materials, paving the way for the development of multifunctional soft devices.

18.
ACS Appl Mater Interfaces ; 16(29): 37840-37852, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38984967

RESUMEN

It is essential and still remains a big challenge to obtain fast-charge anodes with large capacities and long lifespans for Li-ion batteries (LIBs). Among all of the alternative materials, molybdenum trioxide shows the advantages of large theoretical specific capacity, distinct tunnel framework, and low cost. However, there are also some key shortcomings, such as fast capacity decaying due to structural instability during Li insertion and poor rate performance due to low intrinsic electron conductivity and ion diffusion capability, dying to be overcome. A unique strategy is proposed to prepare Ti-h-MoO3-x@TiO2 nanosheets by a one-step hydrothermal approach with NiTi alloy as a control reagent. The density functional theory (DFT) calculations indicate that the doping of Ti element can make the hexagonal h-MoO3-x material show the best electronic structure and it is favor to be synthesized. Furthermore, the hexagonal Ti-h-MoO3-x material has better lithium storage capacity and lithium diffusion capacity than the orthogonal α-MoO3 material, and its theoretical capacity is more than 50% higher than that of the orthogonal α-MoO3 material. Additionally, it is found that Ti-h-MoO3-x@TiO2 as an anode displays extremely high reversible discharge/charge capacities of 1326.8/1321.3 mAh g-1 at 1 A g-1 for 800 cycles and 611.2/606.6 mAh g-1 at 5 A g-1 for 2000 cycles. Thus, Ti-h-MoO3-x@TiO2 can be considered a high-power-density and high-energy-density anode material with excellent stability for LIBs.

19.
Chemistry ; 30(53): e202401916, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39023507

RESUMEN

Photodynamic therapy (PDT) can destroy tumor cells by generating singlet oxygen (1O2) under light irradiation, which is limited by the hypoxia of the neoplastic tissue. Chemodynamic therapy (CDT) can produce toxic hydroxyl radical (⋅OH) to eradicate tumor cells by catalytic decomposition of endogenous hydrogen peroxide (H2O2), the therapeutic effect of which is highly dependent on the concentration of H2O2. Herein, we propose a BODIPY-ferrocene conjugate with a balanced 1O2 and ⋅OH generation capacity, which can serve as a high-efficiency antitumor agent by combining PDT and CDT. The ferrocene moieties endow the as-prepared conjugates with the ability of chemodynamic killing of tumor cells. Moreover, combined PDT/CDT therapy with improved antitumor efficiency can be realized after exposure to light irradiation. Compared with the monotherapy by PDT or CDT, the BODIPY-ferrocene conjugates can significantly increase the intracellular ROS levels of the tumor cells after light irradiation, thereby inducing the tumor cell apoptosis at low drug doses. In this way, a synergistic antitumor treatment is achieved by the combination of PDT and CDT.


Asunto(s)
Antineoplásicos , Compuestos de Boro , Compuestos Ferrosos , Metalocenos , Fotoquimioterapia , Fármacos Fotosensibilizantes , Oxígeno Singlete , Compuestos Ferrosos/química , Compuestos Ferrosos/farmacología , Metalocenos/química , Compuestos de Boro/química , Compuestos de Boro/farmacología , Humanos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Antineoplásicos/química , Antineoplásicos/farmacología , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Peróxido de Hidrógeno/química , Radical Hidroxilo/química , Radical Hidroxilo/metabolismo , Especies Reactivas de Oxígeno/metabolismo
20.
J Cheminform ; 16(1): 89, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080777

RESUMEN

Machine learning is becoming a preferred method for the virtual screening of organic materials due to its cost-effectiveness over traditional computationally demanding techniques. However, the scarcity of labeled data for organic materials poses a significant challenge for training advanced machine learning models. This study showcases the potential of utilizing databases of drug-like small molecules and chemical reactions to pretrain the BERT model, enhancing its performance in the virtual screening of organic materials. By fine-tuning the BERT models with data from five virtual screening tasks, the version pretrained with the USPTO-SMILES dataset achieved R2 scores exceeding 0.94 for three tasks and over 0.81 for two others. This performance surpasses that of models pretrained on the small molecule or organic materials databases and outperforms three traditional machine learning models trained directly on virtual screening data. The success of the USPTO-SMILES pretrained BERT model can be attributed to the diverse array of organic building blocks in the USPTO database, offering a broader exploration of the chemical space. The study further suggests that accessing a reaction database with a wider range of reactions than the USPTO could further enhance model performance. Overall, this research validates the feasibility of applying transfer learning across different chemical domains for the efficient virtual screening of organic materials.Scientific contributionThis study verifies the feasibility of applying transfer learning to large language models in different chemical fields to help organic materials perform virtual screening. Through the comparison of transfer learning from different chemical fields to a variety of organic material molecules, the high precision virtual screening of organic materials is realized.

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