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1.
Sci Rep ; 14(1): 15113, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956421

RESUMEN

The aims of this study were to determine whether human umbilical cord mesenchymal stem cells (hucMSCs) modified by miRNA-25-3p (miR-25-3p) overexpression could promote venous endothelial cell proliferation and attenuate portal endothelial cell injury. HucMSCs and human umbilical vein endothelial cells (HUVEC) were isolated and cultured from human umbilical cord and characterized. Lentiviral vectors expressing miRNA-25-3p were transfected into hucMSCs and confirmed by PCR. We verified the effect of miR-25-3p-modified hucMSCs on HUVEC by cell co-culture and cell supernatant experiments. Subsequently, exosomes of miR-25-3p-modified hucMSCs were isolated from cell culture supernatants and characterized by WB, NTA and TEM. We verified the effects of miR-25-3p-modified exosomes derived from hucMSCs on HUVEC proliferation, migration, and angiogenesis by in vitro cellular function experiments. Meanwhile, we further examined the downstream target genes and signaling pathways potentially affected by miR-25-3p-modified hucMSC-derived exosomes in HUVEC. Finally, we established a rat portal vein venous thrombosis model by injecting CM-DiR-labeled hucMSCs intravenously into rats and examining the homing of cells in the portal vein by fluorescence microscopy. Histological and immunohistochemical experiments were used to examine the effects of miRNA-25-3p-modified hucMSCs on the proliferation and damage of portal vein endothelial cells. Primary hucMSCs and HUVECs were successfully isolated, cultured and characterized. Primary hucMSCs were modified with a lentiviral vector carrying miR-25-3p at MOI 80. Co-culture and cell supernatant intervention experiments showed that overexpression of miRNA-25-3p in hucMSCs enhanced HUVEC proliferation, migration and tube formation in vitro. We successfully isolated and characterized exosomes of miR-25-3p-modified hucMSCs, and exosome intervention experiments demonstrated that miR-25-3p-modified exosomes derived from hucMSCs similarly enhanced the proliferation, migration, and angiogenesis of HUVECs. Subsequent PCR and WB analyses indicated PTEN/KLF4/AKT/ERK1/2 as potential pathways of action. Analysis in a rat portal vein thrombosis model showed that miR-25-3p-modified hucMSCs could homing to damaged portal veins. Subsequent histological and immunohistochemical examinations demonstrated that intervention with miR-25-3p overexpression-modified hucMSCs significantly reduced damage and attenuated thrombosis in rat portal veins. The above findings indicate suggest that hucMSCs based on miR-25-3p modification may be a promising therapeutic approach for use in venous thrombotic diseases.


Asunto(s)
Proliferación Celular , Exosomas , Células Endoteliales de la Vena Umbilical Humana , Células Madre Mesenquimatosas , MicroARNs , Vena Porta , MicroARNs/genética , MicroARNs/metabolismo , Humanos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Animales , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Ratas , Exosomas/metabolismo , Exosomas/genética , Vena Porta/metabolismo , Movimiento Celular/genética , Ratas Sprague-Dawley , Masculino , Trombosis de la Vena/genética , Trombosis de la Vena/metabolismo , Trombosis de la Vena/patología , Trombosis de la Vena/terapia , Células Cultivadas , Técnicas de Cocultivo , Transducción de Señal , Cordón Umbilical/citología
2.
J Hazard Mater ; 475: 134855, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38880044

RESUMEN

Cadmium (Cd) is a common environmental pollutant, while selenium (Se) can ameliorate heavy metal toxicity. Consequently, this study aimed to investigate the protective effects of Se against Cd-induced hepatocyte injury and its underlying mechanisms. To achieve this, we utilized the Dongdagou-Xinglong cohort, BRL3A cell models, and a rat model exposed to Cd and/or Se. The results showed that Se counteracted liver function injury and the decrease in GPER1 levels caused by environmental Cd exposure, and various methods confirmed that Se could protect against Cd-induced hepatotoxicity both in vivo and in vitro. Mechanistically, Cd caused excessive mitophagy activation, evidenced by the colocalization of LC3B, PINK1, Parkin, P62, and TOMM20. Transfection of BRL3A cells with mt-keima adenovirus indicated that Cd inhibited autophagosome-lysosome fusion, thereby impeding mitophagic flux. Importantly, G1, a specific agonist of GPER1, mitigated Cd-induced mitophagy overactivation and hepatocyte toxicity, whereas G15 exacerbates these effects. Notably, Se supplementation attenuated Cd-induced GPER1 protein reduction and excessive mitophagy activation while facilitating autophagosome-lysosome fusion, thereby restoring mitophagic flux. In conclusion, this study proposed a novel mechanism whereby Se alleviated GPER1-mediated mitophagy and promoted autophagosome-lysosome fusion, thus restoring Cd-induced mitophagic flux damage, and preventing hepatocyte injury.


Asunto(s)
Cadmio , Enfermedad Hepática Inducida por Sustancias y Drogas , Hepatocitos , Mitofagia , Receptores Acoplados a Proteínas G , Selenio , Animales , Mitofagia/efectos de los fármacos , Cadmio/toxicidad , Receptores Acoplados a Proteínas G/metabolismo , Masculino , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Selenio/farmacología , Ratas , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Línea Celular , Ratas Sprague-Dawley , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología
3.
J Colloid Interface Sci ; 668: 492-501, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691959

RESUMEN

The improvement of surface reactivity in noble-metal-free cocatalysts is crucial for the development of efficient and cost-effective photocatalytic systems. However, the influence of crystallinity on catalytic efficacy has received limited attention. Herein, we report the utilization of structurally disordered MoSe2 with abundant 1T phase as a versatile cocatalyst for photocatalytic hydrogen evolution. Using MoSe2/carbon nitride (CN) hybrids as a case study, it is demonstrated that amorphous MoSe2 significantly enhances the hydrogen evolution rate of CN, achieving up to 11.37 µmol h-1, surpassing both low crystallinity (8.24 µmol h-1) and high crystallinity MoSe2 (3.86 µmol h-1). Experimental analysis indicates that the disordered structure of amorphous MoSe2, characterized by coordination-unsaturated surface sites and a rich 1T phase with abundant active sites at the basal plane, predominantly facilitates the conversion of surface-bound protons to hydrogen. Conversely, the heightened charge transfer capacity of the highly crystalline counterpart plays a minor role in enhancing practical catalytic performance. This approach is applicable for enhancing the photocatalytic hydrogen evolution performance of various semiconducting photocatalysts, including CdS, TiO2, and ZnIn2S4, thereby offering novel insights into the advancement of high-performance non-precious catalysts through phase engineering.

4.
J Colloid Interface Sci ; 670: 348-356, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38763030

RESUMEN

The depressed directional separation of photogenerated carriers and weak CO2 adsorption/activation activity are the main factors hampering the development of artificial photosynthesis. Herein, Na ions are embedded in graphitic carbon nitride (g-C3N4) to achieve directional migration of the photogenerated electrons to Na sites, while the electron-rich Na sites enhance CO2 adsorption and activation. Na/g-C3N4 (NaCN) shows improved photocatalytic reduction activity of CO2 to CO and CH4, and under simulated sunlight irradiation, the CO yield of NaCN synthesized by embedding Na at 550°C (NaCN-550) is 371.2 µmol g-1 h-1, which is 58.9 times more than that of the monomer g-C3N4. By means of theoretical calculations and experiments including in situ fourier transform infrared spectroscopy, the mechanism is investigated. This strategy which improves carrier separation and reduces the energy barrier at the same time is important to the development of artificial photosynthesis.

5.
Sci Rep ; 14(1): 8023, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580805

RESUMEN

Toxic metals are vital risk factors affecting serum ion balance; however, the effect of their co-exposure on serum ions and the underlying mechanism remain unclear. We assessed the correlations of single metal and mixed metals with serum ion levels, and the mediating effects of mineralocorticoids by investigating toxic metal concentrations in the blood, as well as the levels of representative mineralocorticoids, such as deoxycorticosterone (DOC), and serum ions in 471 participants from the Dongdagou-Xinglong cohort. In the single-exposure model, sodium and chloride levels were positively correlated with arsenic, selenium, cadmium, and lead levels and negatively correlated with zinc levels, whereas potassium and iron levels and the anion gap were positively correlated with zinc levels and negatively correlated with selenium, cadmium and lead levels (all P < 0.05). Similar results were obtained in the mixed exposure models considering all metals, and the major contributions of cadmium, lead, arsenic, and selenium were highlighted. Significant dose-response relationships were detected between levels of serum DOC and toxic metals and serum ions. Mediation analysis showed that serum DOC partially mediated the relationship of metals (especially mixed metals) with serum iron and anion gap by 8.3% and 8.6%, respectively. These findings suggest that single and mixed metal exposure interferes with the homeostasis of serum mineralocorticoids, which is also related to altered serum ion levels. Furthermore, serum DOC may remarkably affect toxic metal-related serum ion disturbances, providing clues for further study of health risks associated with these toxic metals.


Asunto(s)
Arsénico , Metales Pesados , Selenio , Humanos , Plomo/toxicidad , Arsénico/toxicidad , Cadmio/toxicidad , Análisis de Mediación , Mineralocorticoides , Intoxicación por Metales Pesados , Zinc , Hierro , Iones , China , Metales Pesados/toxicidad
6.
World J Gastrointest Oncol ; 16(4): 1213-1226, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38660630

RESUMEN

BACKGROUND: Portal vein thrombosis (PVT), a complication of liver cirrhosis, is a major public health concern. PVT prediction is the most effective method for PVT diagnosis and treatment. AIM: To develop and validate a nomogram and network calculator based on clinical indicators to predict PVT in patients with cirrhosis. METHODS: Patients with cirrhosis hospitalized between January 2016 and December 2021 at the First Hospital of Lanzhou University were screened and 643 patients with cirrhosis who met the eligibility criteria were retrieved. Following a 1:1 propensity score matching 572 patients with cirrhosis were screened, and relevant clinical data were collected. PVT risk factors were identified using the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression analysis. Variance inflation factors and correlation matrix plots were used to analyze multicollinearity among the variables. A nomogram was constructed to predict the probability of PVT based on independent risk factors for PVT, and its predictive performance was verified using a receiver operating characteristic curve (ROC), calibration curves, and decision curve analysis (DCA). Finally, a network calculator was constructed based on the nomograms. RESULTS: This study enrolled 286 cirrhosis patients with PVT and 286 without PVT. LASSO analysis revealed 13 variables as strongly associated with PVT occurrence. Multivariate logistic regression analysis revealed nine indicators as independent PVT risk factors, including etiology, ascites, gastroesophageal varices, platelet count, D-dimer, portal vein diameter, portal vein velocity, aspartate transaminase to neutrophil ratio index, and platelet-to-lymphocyte ratio. LASSO and correlation matrix plot results revealed no significant multicollinearity or correlation among the variables. A nomogram was constructed based on the screened independent risk factors. The nomogram had excellent predictive performance, with an area under the ROC curve of 0.821 and 0.829 in the training and testing groups, respectively. Calibration curves and DCA revealed its good clinical performance. Finally, the optimal cutoff value for the total nomogram score was 0.513. The sensitivity and specificity of the optimal cutoff values were 0.822 and 0.706, respectively. CONCLUSION: A nomogram for predicting PVT occurrence was successfully developed and validated, and a network calculator was constructed. This can enable clinicians to rapidly and easily identify high PVT risk groups.

7.
J Colloid Interface Sci ; 667: 713-722, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38670014

RESUMEN

The emissions of CO2 are increasing year by year, which have led to serious environmental problems. Converting CO2 into valuable fuels through photocatalysis is a promising strategy. In this research, oxygen atoms were successfully innovated into graphitic carbon nitride (CN). Additionally, cobalt porphyrin (CoTPP) was successfully loaded onto the modified carbon nitride (Co/CN). The generation of interfacial electric fields and bending bands between CN and CoTPP was demonstrated experimentally. The electrons in the CN and the holes in the CoTPP were combined to form a unique S-scheme heterojunction structure, and efficient separation of carriers was promoted. As a result, the CO conversion under visible light irradiation reached an impressive 100.70 µmol g-1 h-1. By integrating theoretical and experimental findings, this study underscores the critical role of catalyst design in enabling efficient photocatalytic CO2 reduction.

8.
ACS Sens ; 9(5): 2429-2439, 2024 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-38668680

RESUMEN

Norovirus (NoV) stands as a significant causative agent of nonbacterial acute gastroenteritis on a global scale, presenting a substantial threat to public health. Hence, the development of simple and rapid analytical techniques for NoV detection holds great importance in preventing and controlling the outbreak of the epidemic. In this work, a self-powered photoelectrochemical (PEC) immunosensor of NoV capsid protein (VP1) was proposed by the π-electron-rich carbon nitride homojunction (ER-CNH) as the photoanode. C4N2 ring derived from π-rich locust bean gum was introduced into the tri-s-triazine structure, creating a large π-delocalized conjugated carbon nitride homojunction. This strategy enhances the C/N atomic ratio, which widens light utilization, narrows the bandgap, and optimizes the electronic band structure of carbon nitride. By introduction of a π-rich conjugated structure, p-type domains were induced within n-type domains to build the internal electric field at the interface, thus forming a p-n homojunction to boost carrier separation and transfer. The ER-CNH photoanode exhibited excellent photoelectric performance and water oxidation capacity. Since VP1 inhibits the water oxidation of the ER-CNH photoanode, the open-circuit potential of the as-prepared PEC immunosensor system was reduced for detecting NoV VP1. The self-powered PEC immunosensor achieved a remarkably low detection limit (∼5 fg mL-1) and displayed high stability and applicability for actual stool samples. This research serves as a foundation concept for constructing immunosensors to detect other viruses and promotes the application of self-powered systems for life safety.


Asunto(s)
Técnicas Electroquímicas , Heces , Norovirus , Norovirus/inmunología , Norovirus/aislamiento & purificación , Norovirus/química , Inmunoensayo/métodos , Humanos , Heces/virología , Heces/química , Técnicas Electroquímicas/métodos , Proteínas de la Cápside/química , Proteínas de la Cápside/inmunología , Nitrilos/química , Técnicas Biosensibles/métodos , Límite de Detección , Electrones
9.
Cancer Rep (Hoboken) ; 7(4): e1978, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38599581

RESUMEN

BACKGROUND AND AIMS: Oncogenesis and tumor development have been related to oxidative stress (OS). The potential diagnostic utility of OS genes in hepatocellular carcinoma (HCC), however, remains uncertain. As a result, this work aimed to create a novel OS related-genes signature that could be used to predict the survival of HCC patients and to screen OS related-genes drugs that might be used for HCC treatment. METHODS: We used The Cancer Genome Atlas (TCGA) database and the Gene Expression Omnibus (GEO) database to acquire mRNA expression profiles and clinical data for this research and the GeneCards database to obtain OS related-genes. Following that, biological functions from Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed on differentially expressed OS-related genes (DEOSGs). Subsequently, the prognostic risk signature was constructed based on DEOSGs from the TCGA data that were screened by using univariate cox analysis, and the Least Absolute Shrinkage and Selection Operator (LASSO) regression, and multivariate cox analysis. At the same time, we developed a prognostic nomogram of HCC patients based on risk signature and clinical-pathological characteristics. The GEO data was used for validation. We used the receiver operating characteristic (ROC) curve, calibration curves, and Kaplan-Meier (KM) survival curves to examine the prediction value of the risk signature and nomogram. Finally, we screened the differentially expressed OS genes related drugs. RESULTS: We were able to recognize 9 OS genes linked to HCC prognosis. In addition, the KM curve revealed a statistically significant difference in overall survival (OS) between the high-risk and low-risk groups. The area under the curve (AUC) shows the independent prognostic value of the risk signature model. Meanwhile, the ROC curves and calibration curves show the strong prognostic power of the nomogram. The top three drugs with negative ratings were ZM-336372, lestaurtinib, and flunisolide, all of which inversely regulate different OS gene expressions. CONCLUSION: Our findings indicate that OS related-genes have a favorable prognostic value for HCC, which sheds new light on the relationship between oxidative stress and HCC, and suggests potential therapeutic strategies for HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Estrés Oxidativo/genética , Nomogramas , Área Bajo la Curva
10.
PLoS One ; 19(4): e0301034, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625855

RESUMEN

An enterprise's ownership structure is crucial for factor allocation efficiency. We used Chinese firm-level data to investigate whether changes in state-owned enterprise ownership structure contribute to resource misallocation, leading to high-quality economic development. We found a U-shaped relationship between non-state shareholding and state-owned enterprises' resource allocation efficiency. An optimal range exists for non-state shareholding. When the shareholding of non-state shareholders reaches 10%-20%, the efficiency of resource allocation is at its highest. Additional research has revealed that mixed shareholding has varying impacts on resource allocation, displaying substantial heterogeneity. These insights offer valuable guidance for future mixed-ownership reforms and serve as a practical reference for economic reforms in other nations, particularly developing countries.

11.
J Colloid Interface Sci ; 664: 736-747, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38492375

RESUMEN

Enhancing the activation of peroxymonosulfate (PMS) is essential for generating more reactive oxygen species in advanced oxidation process (AOPs). Nevertheless, improving PMS adsorption and expediting interfacial electron transfer to enhance reaction kinetics pose significant challenges. Herein, we construct confined W18O49 nanowires with asymmetric active centers containing Co-Vo-W (Vo: oxygen vacancy). The design incorporates surface-rich Vo and single-atom Co, and the resulting material is employed for PMS activation in water purification. By coupling unsaturated coordinated electrons in Vo with low-valence Co single atoms to construct an the "electron fountainhead", the adsorption and activation of PMS are enhanced. This results in the generation of more active free radicals (SO4•-, •OH, •O2-) and non-free radicals (1O2) for the decomposition of micropollutants. Thereinto, the degradation rate of bisphenol A (BPA) by Co-W18O49 is 32.6 times faster that of W18O49 monomer, which is also much higher than those of other transition-metal-doped W18O49 composites. This work is expected to help to elucidate the rational design and efficient PMS activation of catalysts with asymmetric active centers.

12.
Sci Total Environ ; 923: 171405, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38432385

RESUMEN

Cadmium (Cd) is a toxic heavy metal that primarily targets the liver. Cd exposure disrupts specific lipid metabolic pathways; however, the underlying mechanisms remain unclear. This study aimed to investigate the lipidomic characteristics of rat livers after Cd exposure as well as the potential mechanisms of Cd-induced liver injury. Our analysis of established Cd-exposed rat and cell models showed that Cd exposure resulted in liver lipid deposition and hepatocyte damage. Lipidomic detection, transcriptome sequencing, and experimental analyses revealed that Cd mainly affects the sphingolipid metabolic pathway and that the changes in ceramide metabolism are the most significant. In vitro experiments revealed that the inhibition of ceramide synthetase activity or activation of ceramide decomposing enzymes ameliorated the proapoptotic and pro-oxidative stress effects of Cd, thereby alleviating liver injury. In contrast, the exogenous addition of ceramide aggravated liver injury. In summary, Cd increased ceramide levels by remodeling ceramide synthesis and catabolism, thereby promoting hepatocyte apoptosis and oxidative stress and ultimately aggravating liver injury. Reducing ceramide levels can serve as a potential protective strategy to mitigate the liver toxicity of Cd. This study provides new evidence for understanding Cd-induced liver injury at the lipidomic level and insights into the health risks and toxicological mechanisms associated with Cd.


Asunto(s)
Cadmio , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Ratas , Animales , Cadmio/metabolismo , Multiómica , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Hígado/metabolismo , Estrés Oxidativo , Ceramidas/metabolismo , Ceramidas/farmacología
13.
Nano Lett ; 24(10): 3028-3035, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38411557

RESUMEN

Multicolor afterglow patterns with transparent and traceless features are important for the exploration of new functionalities and applications. Herein, we report a direct in situ patterning technique for fabricating afterglow carbon dots (CDs) based on laser direct writing (LDW) for the first time. We explore a facile step-scanning method that reduces the heat-affected zone and avoids uneven heating, thus producing a fine-resolution afterglow CD pattern with a minimum line width of 80 µm. Unlike previous LDW-induced luminescence patterns, the patterned CD films are traceless and transparent, which is mainly attributed to a uniform heat distribution and gentle temperature rise process. Interestingly, by regulating the laser parameters and CD precursors, an increased carbonization and oxidation degree of CDs could be obtained, thus enabling time-dependent, tunable afterglow colors from blue to red. In addition, we demonstrate their potential applications in the in situ fabrication of flexible and stretchable optoelectronics.

14.
J Pharm Biomed Anal ; 242: 116011, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359492

RESUMEN

Liver cancer and gastric cancer have extremely high morbidity and mortality rates worldwide. It is well known that an increase or decrease in trace metals may be associated with the formation and development of a variety of diseases, including cancer. Therefore, this study aimed to evaluate the contents of aluminium (Al), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) in cancerous liver and gastric tissues, compared to adjacent healthy tissues, and to investigate the relationship between trace metals and cancer progression. During surgery, multiple samples were taken from the cancerous and adjacent healthy tissues of patients with liver and gastric cancer, and trace metal levels within these samples were analysed using inductively coupled plasma mass spectrometry (ICP-MS). We found that concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn in tissues from patients with liver cancer were significantly lower than those in healthy controls (P < 0.05). Similarly, patients with gastric cancer also showed lower levels of Cd, Co, Cr, Mn, Ni, and Zn-but higher levels of Cu and Se-compared to the controls (P < 0.05). In addition, patients with liver and gastric cancers who had poorly differentiated tumours and positive lymph node metastases showed lower levels of trace metals (P < 0.05), although no significant changes in their concentrations were observed to correlate with sex, age, or body mass index (BMI). Logistic regression, principal component analysis (PCA), Bayesian kernel regression (BKMR), weighted quantile sum (WQS) regression, and quantile-based g computing (qgcomp) models were used to analyse the relationships between trace metal concentrations in liver and gastric cancer tissues and the progression of these cancers. We found that single or mixed trace metal levels were negatively associated with poor differentiation and lymph node metastasis in both liver and gastric cancer, and the posterior inclusion probability (PIP) of each metal showed that Cd contributed the most to poor differentiation and lymph node metastasis in both liver and gastric cancer (all PIP = 1.000). These data help to clarify the relationship between changes in trace metal levels in cancerous liver and gastric tissues and the progression of these cancers. Further research is warranted, however, to fully elucidate the mechanisms and causations underlying these findings.


Asunto(s)
Arsénico , Neoplasias Hepáticas , Metales Pesados , Selenio , Neoplasias Gástricas , Oligoelementos , Humanos , Cadmio , Teorema de Bayes , Plomo , Metástasis Linfática , Oligoelementos/análisis , Zinc , Níquel , Cobalto
15.
Angew Chem Int Ed Engl ; 63(3): e202316973, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38051287

RESUMEN

This work reports that a low-temperature thermal calcination strategy was adopted to modulate the electronic structure and attain an abundance of surface-active sites while maintaining the crystal morphology. All the experiments demonstrate that the new photocatalyst nano MIL-125(Ti)-250 obtained by thermal calcination strategy has abundant Ti3+ induced by oxygen vacancies and high specific surface area. This facilitates the adsorption and activation of N2 molecules on the active sites in the photocatalytic nitrogen fixation. The photocatalytic NH3 yield over MIL-125(Ti)-250 is enhanced to 156.9 µmol g-1 h-1 , over twice higher than that of the parent MIL-125(Ti) (76.2 µmol g-1 h-1 ). Combined with density function theory (DFT), it shows that the N2 adsorption pattern on the active sites tends to be from "end-on" to "side-on" mode, which is thermodynamically favourable. Moreover, the electrochemical tests demonstrate that the high atomic ratio of Ti3+ /Ti4+ can enhance carrier separation, which also promotes the efficiency of photocatalytic N2 fixation. This work may offer new insights into the design of innovative photocatalysts for various chemical reduction reactions.

16.
Adv Sci (Weinh) ; 10(36): e2307192, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072660

RESUMEN

Enhancing charge separation in semiconductor photocatalysts is a major challenge for efficient artificial photosynthesis. Herein, a compact heterojunction is designed by embedding half-metallic C(CN)3 (hm-CN) hydrothermally in BiOBr (BOB) as the backbone. The interface between hm-CN and BOB is seamless and formed by covalent bonding to facilitate the transmission of photoinduced electrons from BOB to hm-CN. The transient photocurrents and electrochemical impedance spectra reveal that the modified composite catalyst exhibits a larger electron transfer rate. The photocatalytic activity of hm-CN/BOB increases significantly as indicated by a CO yield that is about four times higher than that of individual components. Density-functional theory calculations verify that the heterojunction improves electron transport and decreases the reaction energy barrier, thus promoting the overall photocatalytic CO2 conversion efficiency. The half-metal nitride coupled semiconductor heterojunctions might have large potential in artificial photosynthesis and related applications.

17.
Ultrason Sonochem ; 101: 106653, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37918293

RESUMEN

The substantial emissions of CO2 greenhouse gases have resulted in severe environmental problems, and research on the implementation of semiconductor materials to minimize CO2 is currently a highly discussed subject. Effective separation of interface charges is a major challenge for efficient piezo-photocatalytic systems. Meanwhile, the ultrasmall-sized metal nanoclusters can shorten the distance of electron transport. Herein, we synthesized Au25(p-MBA)18 nanoclusters (Au25 NCs) modified red graphitic carbon nitride (RCN) nanocatalysts with highly exposed Au active sites by in-situ seed growth method. The loading of Au25 NCs on the RCN surface provides more active sites and creates a long-range ordered electric field. It allows for the direct utilization of the piezoelectric field to separate photogenerated carriers during photo-piezoelectric excitation. Based on the above advantages, the rate of CO2 reduction to CO over Au25 NCs/RCN (111.95 µmol g-1 h-1) was more than triple compared to that of pristine RCN. This paper has positive implication for further application of metal clusters loaded semiconductor for piezo-photocatalytic CO2 reduction.

18.
Materials (Basel) ; 16(22)2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38005126

RESUMEN

With the development of modern society, environmental pollution and energy shortage have become the focus of worldwide attention [...].

19.
JAMA Netw Open ; 6(7): e2321644, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37399009

RESUMEN

Importance: The NASONE (Nasal Oscillation Post-Extubation) trial showed that noninvasive high-frequency oscillatory ventilation (NHFOV) slightly reduces the duration of invasive mechanical ventilation (IMV) in preterm infants, whereas NHFOV and noninvasive intermittent positive pressure ventilation (NIPPV) result in fewer reintubations than nasal continuous positive airway pressure (NCPAP). It is unknown whether NHFOV is similarly effective in extremely preterm neonates or in those with more severe respiratory failure (based on the duration of previous ventilation and CO2 levels). Objective: To clarify whether NHFOV is better than NIPPV and NCPAP in reducing the duration of IMV in extremely preterm neonates or those with severe respiratory failure. Design, Setting, and Participants: This study is a predefined secondary analyses of a multicenter randomized clinical trial that was performed at tertiary academic neonatal intensive care units (NICUs) in China. Participants included neonates enrolled in the NASONE trial between December 2017 and May 2021 and belonging to 3 predefined subgroups: (1) born at less than or equal to 28 weeks' (plus 6 days) gestation, (2) invasively ventilated for more than 1 week from birth, and (3) with CO2 greater than 50 mm Hg before or in the 24 hours after extubation. Data analysis was performed in August 2022. Intervention: NCPAP, NIPPV, or NHFOV since the first extubation and until NICU discharge, with airway pressure higher in NHFOV than in NIPPV and than in NCPAP. Main Outcomes and Measures: The co-primary outcomes were total duration of IMV during the NICU stay, need for reintubation, and ventilator-free days calculated as per the original trial protocol. Outcomes were analyzed on an intention-to-treat basis as for the whole trial, and subgroup analyses followed the original statistical plan. Results: Among 1137 preterm infants, 455 (279 boys [61.3%]) were born at 28 weeks' gestation or less, 375 (218 boys [58.1%]) underwent IMV for more than 1 week from birth, and 307 (183 boys [59.6%]) had CO2 greater than 50 mm Hg before or in the 24 hours after extubation. Both NIPPV and NHFOV were associated with significantly fewer reintubations (risk difference range, -28% [95% CI, -39% to -17%] to -15% [95% CI, -25% to -4%]; number needed to treat, 3-7 infants) and early reintubations (risk difference range, -24% [95% CI, -35% to -14%] to -20% [95% CI, -30% to -10%]) than NCPAP, and these reintubations were less frequently due to refractory hypoxemia. IMV was shorter in the NIPPV and NHFOV groups (mean difference range, -5.0 days [95% CI, -6.8 to -3.1 days] to -2.3 days [95% CI, -4.1 to -0.4 days]) than in the NCPAP group. Co-primary outcomes were not different between NIPPV and NHFOV; there was no significant interaction effect. Infants in the NHFOV group showed significantly less moderate-to-severe bronchopulmonary dysplasia than infants in the NCPAP group (range, -12% to -10%; number needed to treat, 8-9 infants) and better postextubation gas exchange in all subgroups. The 3 interventions were provided at different mean airway pressure and were equally safe. Conclusions and Relevance: The subgroup analyses of extremely preterm or more ill infants confirm the results obtained in the whole population: NIPPV and NHFOV appeared equally effective in reducing duration of IMV compared with NCPAP. Trial Registration: ClinicalTrials.gov Identifier: NCT03181958.


Asunto(s)
Ventilación con Presión Positiva Intermitente , Insuficiencia Respiratoria , Masculino , Lactante , Recién Nacido , Humanos , Ventilación con Presión Positiva Intermitente/métodos , Presión de las Vías Aéreas Positiva Contínua , Extubación Traqueal , Dióxido de Carbono , Recien Nacido Extremadamente Prematuro , Insuficiencia Respiratoria/terapia
20.
Small ; 19(47): e2304294, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37490529

RESUMEN

The rational design of efficient and multifunctional electrocatalysts for energy conversion devices is one of the major challenges for clean and renewable energy transition. Herein, the local electronic structure of cobalt-platinum nanoclusters is regulated by adjacent platinum atomic site encapsulated in N-doped hollow carbon nanotubes (PtSA -PtCo NCs/N-CNTs) by pyrolysis of melamine-orientation-induced zeolite imidazole metal-organic frameworks (ZIF-67) with thimbleful platinum doping. The introduction of melamine can reactivate adjacent carbon atoms and initiate the oriented growth of nitrogen-doped carbon nanotubes. The systematic analysis suggests the significant role of thimbleful neighboring low-coordinated Pt─N2 in altering the localized electronic structure of PtCo nanoclusters. The optimized PtSA -PtCo NCs/N-CNTs-900 exhibit excellent hydrogen evolution reaction (HER)/oxygen evolution reaction (OER)/oxygen reduction reaction (ORR)/ catalytic performance reaching the current density of 10 mA cm-2 in 1 m KOH under the low 47 (HER) and 252 mV (OER) overpotentials, and a high half-wave potential of 0.86 and 0.89 V (ORR) in 0.1 m KOH and 0.1 m HClO4 , respectively. Remarkably, the PtSA -PtCo NC/N-CNT-900 also presents outstanding catalytic performances toward water splitting and rechargeable Zn-air batteries. The theoretical calculations reveal that optimal regulation of the electronic structure of PtCo nanoclusters by thimbleful neighboring Pt atomic reduces the reaction energy barrier in electrochemical process, facilitating the ORR/OER/HER performance.

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