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1.
Phys Chem Chem Phys ; 26(15): 12084-12096, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38586994

RESUMO

Superlattices constructed with the wide-band-gap semiconductor ZnO and magnetic oxide FeO, both in the wurtzite structure, have been investigated using spin-polarized first-principles calculations. The structural, electronic and magnetic properties of the (ZnO)n/(w-FeO)n superlattices were studied in great detail. Two different interfaces in the (ZnO)n/(w-FeO)n superlattices were identified and they showed very different magnetic and electronic properties. Local symmetry-driven interfacial magnetization and electronic states can arise from different Fe/Zn distributions at different interfaces or spin ordering of Fe in the superlattice. The local symmetry-driven interfacial magnetization and electronic states, originating either from different Fe/Zn distribution across interfaces I and II, or by spin ordering of Fe in the superlattice, can be identified. It was also found that, in the case of the ferromagnetic phase, the electrons are more delocalized for the majority spin but strongly localized for the minority spin, which resulted in interesting spin-dependent transport properties. Our results will pave the way for designing novel spin-dependent electronic devices through the construction of superlattices from semiconductors and multiferroics.

2.
Huan Jing Ke Xue ; 45(5): 3078-3087, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629568

RESUMO

Microplastic pollution is a central issue of great concern in the current environmental field. Microplastic pollution in marine environmental media is widely reported, but the characteristics of microplastic pollution in deep sediments are rarely reported. Based on this, three sampling points were set up on the muddy coast near the Haizhou Bay, a typical aquaculture sea area, to analyze the characteristics of microplastic pollution in sediment column samples. The study showed that the abundance of microplastics in the sediments of the study area was(0.12 ± 0.07)n·g-1, which was at the medium pollution level. The total amount of microplastics in the sediment column was 3.43-6.00 times the abundance of microplastics in the surface sediment (5 cm). The abundance of microplastics in the sediment column samples showed regional differences. There was no significant difference in the abundance of microplastics in the sediment at different depths, but the index decreased with the increase in depth. The relationship between sediment moisture content, depth, and microplastics indicated that the abundance of microplastics in sediment was related to the physical properties of the sediment. Transparent and black microplastics accounted for the highest proportion in each station. Fiber was the most common form of microplastics in the sediment, and microplastics with small particle size accounted for the majority. The density of microplastics did not prevent its appearance in the sediment. The pollution characteristics of microplastics varied greatly in different depths of sediments.

3.
Chem Asian J ; : e202400175, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630005

RESUMO

Alkaline earth (AE) metal complexes have garnered significant interest in various functional fields due to their nontoxicity, low density, and low cost. However, there is a lack of systematic investigation into the structural characteristics and physical properties of AE-metal-organic frameworks (MOFs). In this research, we synthesized isostructural MOFs consisting of AE4(µ4-Cl) clusters bridged by benzo-(1,2;3,4;5,6)-tris(thiophene-2'-carboxylic acid) (BTTC3-) ligands. The resulting structure forms a truncated octahedral cage denoted as [AE4(m4-Cl)]6(BTTC)8, which further linked to a porous three-dimensional framework. Among the investigated AE ions (Ca, Sr, and Ba), the Ca4-MOF demonstrated good chemical stability in water compared to Sr4-MOF and Ba4-MOF. The N2 adsorption and solid-state UV-vis-NIR absorption behaviors were evaluated for all AE4-MOFs, showing similar trends among the different metal ions. Additionally, the proton conduction study revealed that the Ca4-MOF exhibited ultra-high proton conductivity, reaching 3.52 × 10-2 S cm-1 at 343 K and 98% RH. Notably, the introduction of LiCl via guest exchange resulted in an improved proton conduction of up to 6.36 × 10-2 S cm-1 under similar conditions in the modified LiCl@Ca4-MOF. The findings shed light on the regulation of physical properties and proton conductivity of AE-MOFs, providing valuable insights for their potential applications in various fields.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38602633

RESUMO

Photocatalytic disinfection is a promising technology with low cost and high efficiency. However, most of the current studies on photocatalytic disinfection ignore the widespread presence of natural organic matter (NOM) in water bodies, so the incomplete conclusions obtained may not be applicable. Herein, this paper systematically studied the influence of humic acid (HA), one of the most important components of NOM, on the photocatalytic inactivation of bacteriophage f2 with electrospinning Cu-TiO2 nanofibers. We found that with the addition of HA, the light transmittance of the solution at 550 nm decreased from 94 to 60%, and the band gap of the photocatalyst was increased from 2.96 to 3.05 eV. Compared with reacting without HA, the degradation amount of RNA of f2 decreased by 88.7% after HA was added, and the RNA concentration increased from 1.95 to 4.38 ng·µL-1 after the reaction. Hence, we propose mechanisms of the effect of HA on photocatalytic disinfection: photo-shielding, passivation of photocatalysts, quenching of free radicals, and virus protection. Photo-shielding and photocatalyst passivation lead to the decrease of photocatalyst activity, and the reactive oxygen species (ROSs) (·OH, ·O2-, 1O2, H2O2) are further trapped by HA. The HA in water also can protect the shape of phage f2 and reduce the leakage of protein and the destruction of ribonucleic acid (RNA). This work provides an insight into the mechanisms for the influence of HA in photocatalytic disinfection process and a theoretical basis for its practical application.

5.
NPJ Precis Oncol ; 8(1): 58, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429411

RESUMO

Abnormal lipid metabolism promotes hepatocellular carcinoma (HCC) progression, which engenders therapeutic difficulties owing to unclear mechanisms of the phenomenon. We precisely described a special steatotic HCC subtype with HBV-related cirrhosis and probed its drivers. Hematoxylin-eosin (HE) staining of 245 HCC samples revealed a special HCC subtype (41 cases) characterized by HBV-related cirrhosis and intratumoral steatosis without fatty liver background, defined as steatotic HCC with HBV-related cirrhosis (SBC-HCC). SBC-HCC exhibits a larger tumor volume and worse prognosis than non-SBC-HCC. Screening for driver genes promoting fatty acid (FA) biosynthesis in the Gao's HBV-related cirrhosis HCC cases and GSE121248' HBV-related HCC cases revealed that high expression of SOCS5 predicts increased FA synthesis and that SOCS5 is upregulated in SBC-HCC. Through proteomics, metabolomics, and both in vivo and in vitro experiments, we demonstrated that SOCS5 induces lipid accumulation to promote HCC metastasis. Mechanistically, through co-IP and GST-pulldown experiments, we found that the SOCS5-SH2 domain, especially the amino acids Y413 and D443, act as critical binding sites for the RBMX-RRM domain. SOCS5-RBMX costimulates the promoter of SREBP1, inducing de novo lipogenesis, while mutations in the SH2 domain, Y413, and D443 reverse this effect. These findings precisely identified SBC-HCC as a special steatotic HCC subtype and highlighted a new mechanism by which SOCS5 promotes SBC-HCC metastasis.

6.
J Geriatr Cardiol ; 21(1): 81-89, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38440336

RESUMO

BACKGROUND: The current understanding of the magnitude and consequences of multimorbidity in Chinese older adults with coronary heart disease (CHD) is insufficient. We aimed to assess the association and population-attributable fractions (PAFs) between multimorbidity and mortality among hospitalized older patients who were diagnosed with CHD in Shenzhen, China. METHODS: We conducted a retrospective cohort study of older Chinese patients (aged ≥ 65 years) who were diagnosed with CHD. Cox proportional hazards models were used to estimate the associations between multimorbidity and all-cause and cardiovascular disease (CVD) mortality. We also calculated the PAFs. RESULTS: The study comprised 76,455 older hospitalized patients who were diagnosed with CHD between January 1, 2016, and August 31, 2022. Among them, 70,217 (91.9%) had multimorbidity, defined as the presence of at least one of the predefined 14 chronic conditions. Those with cancer, hemorrhagic stroke and chronic liver disease had the worst overall death risk, with adjusted HRs (95% CIs) of 4.05 (3.77, 4.38), 2.22 (1.94, 2.53), and 1.85 (1.63, 2.11), respectively. For CVD mortality, the highest risk was observed for hemorrhagic stroke, ischemic stroke, and chronic kidney disease; the corresponding adjusted HRs (95% CIs) were 3.24 (2.77, 3.79), 1.91 (1.79, 2.04), and 1.81 (1.64, 1.99), respectively. All-cause mortality was mostly attributable to cancer, heart failure and ischemic stroke, with PAFs of 11.8, 10.2, and 9.1, respectively. As for CVD mortality, the leading PAFs were heart failure, ischemic stroke and diabetes; the corresponding PAFs were 18.0, 15.7, and 6.1, respectively. CONCLUSIONS: Multimorbidity was common and had a significant impact on mortality among older patients with CHD in Shenzhen, China. Cancer, heart failure, ischemic stroke and diabetes are the primary contributors to PAFs. Therefore, prioritizing improved treatment and management of these comorbidities is essential for the survival prognosis of CHD patients from a holistic public health perspective.

7.
Chem Biodivers ; 21(4): e202400135, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38425248

RESUMO

Four series of novel pyridine derivatives (17 a-i, 18 a-i, 19 a-e, and 20 a-e) were synthesized and their antimicrobial activities were evaluated. Of all the target compounds, almost half target compounds showed moderate or high antibacterial activity. The 4-F substituted compound 17 d (MIC=0.5 µg/mL) showed the highest antibacterial activity, its activity was twice the positive control compound gatifloxacin (MIC=1.0 µg/mL). For fungus ATCC 9763, the activities of compounds 17 a and 17 d are equivalent to the positive control compound fluconazole (MIC=8 µg/mL). Furthermore, compounds 17 a and 17 d showed little cytotoxicity to human LO2 cells, and did not show hemolysis even at ultra-high concentration (200 µM). The results indicate that these compounds are valuable for further development as antibacterial and antifungal agents.


Assuntos
Tiadiazóis , Humanos , Tiadiazóis/farmacologia , Antifúngicos/farmacologia , Antibacterianos/farmacologia , Fungos , Piridinas/farmacologia , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
8.
DNA Repair (Amst) ; 137: 103669, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507953

RESUMO

The SMC5/6 complex is evolutionarily conserved across all eukaryotes and plays a pivotal role in preserving genomic stability. Mutations in genes encoding SMC5/6 complex subunits have been associated with human lung disease, immunodeficiency, and chromosome breakage syndrome. Despite its critical importance, much about the SMC5/6 complex remains to be elucidated. Various evidences have suggested possible role of a subunit of the SMC5/6 complex, NSE1, in chromosome segregation and DNA repair. Current knowledge regarding the role of NSE1 is primarily derived from single-cell-based analyses in yeasts, Arabidopsis thaliana, and human cell lines. However, our understanding of its function is still limited and requires further investigation. This study delves into the role of nse-1 in Caenorhabditis elegans, revealing its involvement in meiotic recombination and DNA repair. nse-1 mutants display reduced fertility, increased male incidence, and increased sensitivity to genotoxic chemicals due to defects in meiotic chromosome segregation and DNA repair. These defects manifest as increased accumulation of RAD-51 foci, increased chromosome fragmentation, and susceptibility to MMS, cisplatin, and HU. Furthermore, nse-1 mutation exacerbates germ cell death by upregulating ced-13 and egl-1 genes involved in the CEP-1/p53-mediated apoptotic pathway. NSE-1 is essential for the proper localization of NSE-4 and MAGE-1 on the chromosomes. Collectively, these findings firmly establish nse-1 as a crucial factor in maintaining genomic stability.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Masculino , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Reparo do DNA , Meiose , Instabilidade Genômica , Proteínas de Caenorhabditis elegans/genética
9.
Eur J Med Chem ; 269: 116311, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38508118

RESUMO

Four series of imidazoles (15a-g, 20c, and 20d) and thiazoles (18a-g, 22a, and 22b) possessing various amino acids were synthesized and evaluated for activin receptor-like kinase 5 (ALK5) inhibitory activities in an enzymatic assay. Among them, compounds 15g and 18c showed the highest inhibitory activity against ALK5, with IC50 values of 0.017 and 0.025 µM, respectively. Compounds 15g and 18c efficiently inhibited extracellular matrix (ECM) deposition in TGF-ß-induced hepatic stellate cells (HSCs), and eventually suppressed HSC activation. Moreover, compound 15g showed a good pharmacokinetic (PK) profile with a favorable half-life (t1/2 = 9.14 h). The results indicated that these compounds exhibited activity targeting ALK5 and may have potential in the treatment of liver fibrosis; thus they are worthy of further study.


Assuntos
Aminoácidos , Tiazóis , Humanos , Tiazóis/farmacologia , Aminoácidos/farmacologia , Cirrose Hepática/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Imidazóis/farmacologia
10.
J Colloid Interface Sci ; 664: 1012-1020, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508029

RESUMO

The development of cost-effective, high-activity and stable catalysts to accelerate the sluggish kinetics of cathodic oxygen reduction/evolution reactions (ORR/OER) plays a critical part in commercialization application of rechargeable Zn-air batteries (RZABs). Herein, a multiscale nanoengineering strategy is developed to simultaneously stabilize Co-doped Fe nanoparticles originated from metal-organic framework-derived approach and atomic Fe/Co sites derived from metal nanoparticle-atomized way on N-doped hierarchically tubular porous carbon substrate. Thereinto, metal nanoparticles and single atoms are respectively used to expedite the OER and ORR. Consequently, the final material is acted as an oxygen electrode catalyst, displaying 0.684 V of OER/ORR potential gap, 260 mW cm-2 of peak power density for liquid-state RZAB, 110 mW cm-2 of peak power density for solid-state RZAB, and 1000 charge-discharge cycles without decay, which confirms great potential for energy storage and conversion applications.

11.
Cancer Lett ; 588: 216768, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38453045

RESUMO

Hedgehog signaling is activated in response to liver injury, and modulates organogenesis. However, the role of non-canonical hedgehog activation via TGF-ß1/SMAD3 in hepatic carcinogenesis is poorly understood. TGF-ß1/SMAD3-mediated non-canonical activation was found in approximately half of GLI2-positive hepatocellular carcinoma (HCC), and two new GLI2 isoforms with transactivating activity were identified. Phospho-SMAD3 interacted with active GLI2 isoforms to transactivate downstream genes in modulation of stemness, epithelial-mesenchymal transition, chemo-resistance and metastasis in poorly-differentiated hepatoma cells. Non-canonical activation of hedgehog signaling was confirmed in a transgenic HBV-associated HCC mouse model. Inhibition of TGF-ß/SMAD3 signaling reduced lung metastasis in a mouse in situ hepatic xenograft model. In another cohort of 55 HCC patients, subjects with high GLI2 expression had a shorter disease-free survival than those with low expression. Moreover, co-positivity of GLI2 with SMAD3 was observed in 87.5% of relapsed HCC patients with high GLI2 expression, indicating an increased risk of post-resection recurrence of HCC. The findings underscore that suppressing the non-canonical hedgehog signaling pathway may confer a potential strategy in the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/patologia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Transgênicos , Proteínas Nucleares/metabolismo , Transdução de Sinais , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína Gli2 com Dedos de Zinco/genética , Proteína Gli2 com Dedos de Zinco/metabolismo
12.
Int J Surg ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38518083

RESUMO

The landscape of current tumor treatment has been revolutionized by the advent of immunotherapy based on PD-1/PD-L1 inhibitors. Leveraging its capacity to mobilize systemic anti-tumor immunity, which is primarily mediated by T cells, there is growing exploration and expansion of its potential value in various stages of clinical tumor treatment. Neoadjuvant immunotherapy induces a robust immune response against tumors prior to surgery, effectively facilitating tumor volume reduction, early eradication or suppression of tumor cell activity, and control of potential metastatic spread, to improve curative surgical resection rates and prevent tumor recurrence. This review delineates the theoretical basis of neoadjuvant immunotherapy from preclinical research evidence, discusses specific challenges in clinical application, and provides a comprehensive overview of clinical research progress in neoadjuvant immunotherapy for gastrointestinal tumors. These findings suggest that neoadjuvant immunotherapy has the potential to ameliorate immunosuppressive states and enhance cytotoxic T cell function while preserving lymphatic drainage in the preoperative period. However, further investigations are needed on specific treatment regimens, suitable patient populations, and measurable endpoints. Despite numerous studies demonstrating the promising efficacy and manageable adverse events of neoadjuvant immunotherapy in gastrointestinal tumors, the availability of high-quality randomized controlled trials is limited, which highlights the necessity for further research.

13.
Small ; : e2400662, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534137

RESUMO

Developing high-performance electrocatalysts for alkaline hydrogen evolution reaction (HER) is crucial for producing green hydrogen, yet it remains challenging due to the sluggish kinetics in alkaline environments. Pt is located near the peak of HER volcano plot, owing to its exceptional performance in hydrogen adsorption and desorption, and Rh plays an important role in H2O dissociation. Lanthanides (Ln) are commonly used to modulate the electronic structure of materials and further influence the adsorption/desorption of reactants, intermediates, and products, and noble metal-Ln alloys are recognized as effective platforms where Ln elements regulate the catalytic properties of noble metals. Here Pt1.5Rh1.5Tm alloy is synthesized using the sodium vapor reduction method. This alloy demonstrates superior catalytic activity, being 4.4 and 6.6 times more effective than Pt/C and Rh/C, respectively. Density Functional Theory (DFT) calculations reveal that the upshift of d-band center and the charge transfer induced by alloying promote adsorption and dissociation of H2O, making Pt1.5Rh1.5Tm alloy more favorable for the alkaline HER reaction, both kinetically and thermodynamically.

14.
ACS Appl Mater Interfaces ; 16(13): 16164-16174, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38514249

RESUMO

Single-metal-site catalysts have recently aroused extensive research in electrochemical energy fields such as zinc-air batteries and water splitting, but their preparation is still a huge challenge, especially in flexible catalyst films. Herein, we propose a sublimation strategy in which metal phthalocyanine molecules with defined isolated metal-N4 sites are gasified by sublimation and then deposited on flexible single-wall carbon nanotube (SWCNT) films by means of π-π coupling interactions. Specifically, iron phthalocyanine anchored on the SWCNT film prepared was directly used to boost the cathodic oxygen reduction reaction of the zinc-air battery, showing a high peak power density of 247 mW cm-2. Nickel phthalocyanine and cobalt phthalocyanine were, respectively, stabilized on SWCNT films as the anodic and cathodic electrocatalysts for water splitting, showing a low potential of 1.655 V at 10 mA cm-2. In situ Raman spectra and theoretical studies demonstrate that highly efficient activities originate from strain-induced metal phthalocyanine on SWCNTs. This work provides a universal preparation method for single-metal-site catalysts and innovative insights for electrocatalytic mechanisms.

15.
Plants (Basel) ; 13(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38502046

RESUMO

In plants exposed to ultraviolet B radiation (UV-B; 280-315 nm), metabolic responses are activated, which reduce the damage caused by UV-B. Although several metabolites responding to UV-B stress have been identified in plants, the accumulation of these metabolites at different time points under UV-B stress remains largely unclear, and the transcription factors regulating these metabolites have not been well characterized. Here, we explored the changes in metabolites in rice after UV-B treatment for 0 h, 6 h, 12 h, and 24 h and identified six patterns of metabolic change. We show that the rice transcription factor OsbZIP18 plays an important role in regulating phenylpropanoid and flavonoid biosynthesis under UV-B stress in rice. Metabolic profiling revealed that the contents of phenylpropanoid and flavonoid were significantly reduced in osbzip18 mutants compared with the wild-type plants (WT) under UV-B stress. Further analysis showed that the expression of many genes involved in the phenylpropanoid and flavonoid biosynthesis pathways was lower in osbzip18 mutants than in WT plants, including OsPAL5, OsC4H, Os4CL, OsCHS, OsCHIL2, and OsF3H. Electrophoretic mobility shift assays (EMSA) revealed that OsbZIP18 bind to the promoters of these genes, suggesting that OsbZIP18 function is an important positive regulator of phenylpropanoid and flavonoid biosynthesis under UV-B stress. In conclusion, our findings revealed that OsbZIP18 is an essential regulator for phenylpropanoid and flavonoid biosynthesis and plays a crucial role in regulating UV-B stress responses in rice.

16.
Carcinogenesis ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38306794

RESUMO

Hepatocellular carcinoma (HCC) exhibits a high mortality rate due to its high invasion and metastatic nature, and the acidic microenvironment plays a pivotal role. Acid-sensing ion channel 1 (ASIC1) is upregulated in HCC tissues and facilitates tumor progression in a pH-dependent manner, while the specific mechanisms therein remain currently unclear. Herein, we aimed to investigate the underlying mechanisms by which ASIC1 contributes to the development of HCC. Using bioinformatics analysis, we found a significant association between ASIC1 expression and malignant transformation of HCC, such as poor prognosis, metastasis and recurrence. Specifically, ASIC1 enhanced the migration and invasion capabilities of Li-7 cells in the in vivo experiment using an HCC lung metastasis mouse model, as well as in the in vitro experiments such as wound healing assay and Transwell assay. Furthermore, our comprehensive gene-chip and molecular biology experiments revealed that ASIC1 promoted HCC migration and invasion by activating the PRKACA/AP-1 signaling pathway. Our findings indicate that targeting ASIC1 could have therapeutic potential for inhibiting HCC progression.

17.
Acta Pharmacol Sin ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326623

RESUMO

G protein-coupled receptors (GPCRs) are expressed in a variety of cell types and tissues, and activation of GPCRs is involved in enormous metabolic pathways, including nutrient synthesis, transportation, storage or insulin sensitivity, etc. This review intends to summarize the regulation of metabolic homeostasis and mechanisms by a series of GPCRs, such as GPR91, GPR55, GPR119, GPR109a, GPR142, GPR40, GPR41, GPR43 and GPR120. With deep understanding of GPCR's structure and signaling pathways, it is attempting to uncover the role of GPCRs in major metabolic diseases, including metabolic syndrome, diabetes, dyslipidemia and nonalcoholic steatohepatitis, for which the global prevalence has risen during last two decades. An extensive list of agonists and antagonists with their chemical structures in a nature of small molecular compounds for above-mentioned GPCRs is provided as pharmacologic candidates, and their preliminary data of preclinical studies are discussed. Moreover, their beneficial effects in correcting abnormalities of metabolic syndrome, diabetes and dyslipidemia are summarized when clinical trials have been undertaken. Thus, accumulating data suggest that these agonists or antagonists might become as new pharmacotherapeutic candidates for the treatment of metabolic diseases.

18.
Phys Chem Chem Phys ; 26(7): 5848-5857, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38299693

RESUMO

Hydrogen is identified as one of the most promising sustainable and clean energy sources. The development of a hydrogen evolution reaction (HER) catalyst with high activity is essential to meet future needs. Considering the novel advantages of two-dimensional materials and the high catalytic activity of atomic transition metals, in this study, using density functional theory calculations, the HER on a single transition metal (10 different TM atoms) adsorbed and doped ZnO monolayer (ZnO-m) has been investigated. The Volmer-Tafel reaction mechanisms and strain engineering of the three best HER catalysts are also discussed. The results show that Pt@ZnO-m, Co-doped ZnO-m and Ir-doped ZnO-m with high stability all have a smaller absolute H adsorption free energy than Pt, and the optimal value of Pt@ZnO-m is -0.017 eV. The calculation of the reaction energy barriers shows that the Volmer-Tafel step is favorable. Co@ZnO-m and Ir@ZnO-m have high HER activity, the widest pH range, and acid-alkali resistance. Pt@ZnO-m and Co-doped ZnO-m maintain excellent HER performances in the strain range of -4% to 4%.

19.
Cancer Commun (Lond) ; 44(3): 384-407, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407942

RESUMO

BACKGROUND: Liver cancer is a malignancy with high morbidity and mortality rates. Serpin family E member 2 (SERPINE2) has been reported to play a key role in the metastasis of many tumors. In this study, we aimed to investigate the potential mechanism of SERPINE2 in liver cancer metastasis. METHODS: The Cancer Genome Atlas database (TCGA), including DNA methylation and transcriptome sequencing data, was utilized to identify the crucial oncogene associated with DNA methylation and cancer progression in liver cancer. Data from the TCGA and RNA sequencing for 94 pairs of liver cancer tissues were used to explore the correlation between SERPINE2 expression and clinical parameters of patients. DNA methylation sequencing was used to detect the DNA methylation levels in liver cancer tissues and cells. RNA sequencing, cytokine assays, immunoprecipitation (IP) and mass spectrometry (MS) assays, protein stability assays, and ubiquitination assays were performed to explore the regulatory mechanism of SERPINE2 in liver cancer metastasis. Patient-derived xenografts and tumor organoid models were established to determine the role of SERPINE2 in the treatment of liver cancer using sorafenib. RESULTS: Based on the public database screening, SERPINE2 was identified as a tumor promoter regulated by DNA methylation. SERPINE2 expression was significantly higher in liver cancer tissues and was associated with the dismal prognosis in patients with liver cancer. SERPINE2 promoted liver cancer metastasis by enhancing cell pseudopodia formation, cell adhesion, cancer-associated fibroblast activation, extracellular matrix remodeling, and angiogenesis. IP/MS assays confirmed that SERPINE2 activated epidermal growth factor receptor (EGFR) and its downstream signaling pathways by interacting with EGFR. Mechanistically, SERPINE2 inhibited EGFR ubiquitination and maintained its protein stability by competing with the E3 ubiquitin ligase, c-Cbl. Additionally, EGFR was activated in liver cancer cells after sorafenib treatment, and SERPINE2 knockdown-induced EGFR downregulation significantly enhanced the therapeutic efficacy of sorafenib against liver cancer. Furthermore, we found that SERPINE2 knockdown also had a sensitizing effect on lenvatinib treatment. CONCLUSIONS: SERPINE2 promoted liver cancer metastasis by preventing EGFR degradation via c-Cbl-mediated ubiquitination, suggesting that inhibition of the SERPINE2-EGFR axis may be a potential target for liver cancer treatment.


Assuntos
Neoplasias Hepáticas , Serpina E2 , Humanos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Neoplasias Hepáticas/genética , Proteínas Proto-Oncogênicas c-cbl/genética , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Serpina E2/genética , Serpina E2/metabolismo , Sorafenibe , Ubiquitinação
20.
Eur J Pharmacol ; 969: 176425, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387717

RESUMO

Acute kidney injury (AKI) is a critical condition often associated with systemic inflammation and dysregulated gut microbiota. This study aimed to investigate the effects of the C5a receptor antagonist W54011 on lipopolysaccharide (LPS)-induced AKI, focusing on the colon's C5a/C5a receptor pathway, intestinal barrier integrity, and gut microbiota. Our findings demonstrate that W54011 effectively ameliorated kidney injury in the LPS-induced AKI model by selectively inhibiting the colon's C5a/C5a receptor signalling pathway. Additionally, C5a receptor blockade resulted in the inhibition of colonic inflammation and the reconstruction of the intestinal mucosal barrier. Furthermore, W54011 administration significantly impacted the composition and stability of the gut microbiota, restoring the abundance of dominant bacteria to levels observed in the normal state of the intestinal flora and reducing the abundance of potentially harmful bacterial groups. In conclusion, W54011 alleviates LPS-induced AKI by modulating the interplay between the colon, gut microbiota, and kidneys. It preserves the integrity of the intestinal barrier and reinstates gut microbiota, thereby mitigating AKI symptoms. These findings suggest that targeting the colon and gut microbiota could be a promising therapeutic strategy for AKI treatment.


Assuntos
Injúria Renal Aguda , Compostos de Anilina , Microbioma Gastrointestinal , Tetra-Hidronaftalenos , Humanos , Lipopolissacarídeos , Receptor da Anafilatoxina C5a , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Rim , Inflamação , Colo
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