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1.
Pediatr Res ; 95(3): 809-818, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37845526

RESUMEN

BACKGROUND: Inequalities in job opportunities and income prompts many Chinese parents to leave rural regions to work in urban regions. Their children are left behind in rural regions, subjected to worse quality of childcare that jeopardizes their development. This study aimed to examine the association between quality of childcare and delayed child development in under-three years children left behind in China. METHODS: Cross-sectional national survey was conducted in children left behind in rural China in 2017. Exploratory and confirmatory factor analysis was used to develop a quality of childcare index. Mutlilevel analyses determined factors associated with quality of childcare and child development on a province and individual level. RESULT: The largest population of at-risk children left behind were found in higher-GDP provinces. Children left behind had the lowest mean quality of childcare score. Multilevel analysis found that province level accounted for a great proportion of variance observed. CONCLUSIONS: While migration to urban regions for work may improve household income, a trade-off in worse quality of childcare and developmental delays exists. With improving household income often being the greatest contributing factor for parental migration, policies to reduce inequalities in job opportunities and wealth between rural and urban regions are required. IMPACT: Previous studies identified higher prevalence of developmental delays in children left behind in China. However, quality of childcare has not been examined. Based on WHO's Nurturing Care Framework, we developed a quality of childcare index to assess its association with child development in children left behind. Greatest proportion of children left behind at-risk of developmental delays resided in higher-GDP states, indicating a trade-off in worse quality of childcare and developmental delays. Since improving household income is the main factor for parental migration, policies to close inequalities in job opportunities and wealth between rural and urban regions are required.


Asunto(s)
Cuidado del Niño , Desarrollo Infantil , Niño , Humanos , Estudios Transversales , Renta , China/epidemiología , Población Rural
2.
Angew Chem Int Ed Engl ; 63(28): e202404123, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38702953

RESUMEN

One challenge confronting the Cu2O catalysts in the electrocatalysis of carbon dioxide reduction reaction (CO2RR) is the reduction of active Cu(I) species, resulting in low selectivity and quick deactivation. In this study, we for the first time introduce a bottom-up growth of convex sphere with adjustable Cu(0)/Cu(I) interfaces (Cux@Cu2O convex spheres). Interestingly, the interfaces are dynamically modulated by varying hydrothermal time, thus regulating the conversion of C1 and C2 products. In particular, the 4 h hydrothermal treatment applied to Cu0.25@Cu2O convex sphere with the favorable Cu(0)/Cu(I) interface results in the highest selectivity for C2 products (90.5 %). In situ Fourier-transform infrared spectroscopy measurements and density functional theory calculations reveal that the Cu(0)/Cu(I) interface lowers the energy barrier for the production of ethylene and ethanol while increasing the coverage of localized *CO adsorbate for increased dimerization. This work establishes a novel approach for transforming the state of valence-sensitive electrocatalysts into high-value energy-related engineering products.

3.
Cell Mol Biol (Noisy-le-grand) ; 69(5): 105-111, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571893

RESUMEN

Sepsis has been characterized as a frequent medical problem with high mortality and severe complication medical problem in the intensive care unit (ICU). Here, qRT-PCR was used to examine circRNA PARG expression levels in patients with sepsis and in human pulmonary microvascular endothelial cells (HPMEC). Lipopolysaccharide (LPS)-simulated HPMEC were hybridized using RNA-Fluorescence in situ hybridization to confirm the location of circRNA PARG and miR-140-3p. The biological role of downregulated circRNA PARGin cellular proliferation, apoptosis, and inflammatory and apoptosis responses was evaluated. performed A dual-luciferase reporter assay was performed to determine the relationship between the circRNA PARG with miR-140-3p. In this study,circRNA PARG aberrant expression was found, and the effects of circRNA PARG on lipopolysaccharide (LPS)-stimulated apoptosis of HPMEC cells were further investigated. Down-regulated circRNA PARG led to significant alleviation of LPS-simulated cell apoptosis via inhibition of inflammatory and apoptosis-related genes, while upregulated circRNA PARG exhibited the opposite effects. Further findings indicated that circRNA PARG positively modulated the relative level of miR-140-3p, which has been confirmed using the luciferase reporter assay. Upregulated circRNA PARG led to a reversal of LPS-simulated cells after transfection of miR-140-3p mimic. In general, a novel insight into understanding the important effects of circRNA PARG in sepsis is provided.


Asunto(s)
MicroARNs , Sepsis , Humanos , ARN Circular/genética , Células Endoteliales , Hibridación Fluorescente in Situ , Lipopolisacáridos/farmacología , Sepsis/genética , Apoptosis/genética , MicroARNs/genética
4.
Molecules ; 28(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37446601

RESUMEN

Melatonin has profound antioxidant activity and numerous functions in humans as well as in livestock and poultry. Additionally, melatonin plays an important role in regulating the biological rhythms of animals. Combining melatonin with scientific breeding management has considerable potential for optimizing animal physiological functions, but this idea still faces significant challenges. In this review, we summarized the beneficial effects of melatonin supplementation on physiology and reproductive processes in cattle, including granulosa cells, oocytes, circadian rhythm, stress, inflammation, testicular function, spermatogenesis, and semen cryopreservation. There is much emerging evidence that melatonin can profoundly affect cattle. In the future, we hope that melatonin can not only be applied to cattle, but can also be used to safely and effectively improve the efficiency of animal husbandry.


Asunto(s)
Crianza de Animales Domésticos , Cruzamiento , Bovinos , Melatonina , Animales , Bovinos/genética , Bovinos/crecimiento & desarrollo , Bovinos/fisiología , Crianza de Animales Domésticos/métodos , Cruzamiento/métodos , Suplementos Dietéticos , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/fisiología , Melatonina/farmacología , Melatonina/fisiología , Oocitos/efectos de los fármacos , Oocitos/fisiología , Reproducción/efectos de los fármacos , Reproducción/fisiología
5.
Angew Chem Int Ed Engl ; 62(21): e202302997, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36943400

RESUMEN

Biological ion channels regulate the ion flow across cell membrane via opening or closing of the pores in response to various external stimuli. Replicating the function of high ion gating effects with artificial porous materials has been challenging. Herein, we report that the self-assembled two-dimensional metal-organic framework (MOF) membrane can serve as an excellent nanofluidic platform for smart regulation of ion transport. The MOF membrane with good photothermal performance exhibits extremely high ion gating ratio (up to 104 ), which is among the highest values in MOF membrane nanochannels for light-controlled ion gating reported so far. By repeatedly turning on and off the light, the nanofluidic device shows outstanding stability and reversibility that can be applied in the remote light-switching system. This work may spark promising applications of MOF membrane with variety of stimuli responsive properties in ion sieving, biosensing, and energy conversion.

6.
Langmuir ; 38(48): 14733-14744, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36412147

RESUMEN

Although intensive efforts have been devoted to fabricating Ti3C2Tx MXene composites for microwave absorption, it remains a great challenge to achieve excellent MA performance at low loading and thin thickness. Herein, a three-dimensional (3D) lightweight hierarchically structured MnO2/Ti3C2Tx/RGO composite aerogel with abundant heterointerfaces was fabricated via a hydrothermal and chemical reduction self-assembly method. The RGO aerogel embedded with laminated MnO2/Ti3C2Tx provides a lot of heterogeneous interfaces, 3D porous interconnected conductive networks, and reasonable combination of various loss materials for rich interfacial polarization, conductivity loss, multiple reflections and scattering, and good impedance matching. Benefiting from the synergy of different loss mechanisms, the maximum reflection loss (RL) is up to -66.5 dB (>99.9999% energy absorption) at only 10 wt % loading and 2.0 mm thickness, and even at only 1.5 mm thickness, the maximum RL value remains at -36 dB (>99.9% energy absorption). The work provides a promising route to construct 3D hierarchically heterogeneous composite aerogels for efficient MA at thin thickness and low loading.

7.
Langmuir ; 38(3): 945-956, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35019654

RESUMEN

Carbon fiber aerogel (CFA) derived from cotton wool as a potential microwave absorbing material has received intensive attention owing to the low density, high conductivity, large surface area, and low cost, but its applications are limited by the relatively high complex permittivity. To solve this problem, TiO2@C (derived from Ti3C2Tx) is introduced into CFA to prepare lightweight TiO2@C/CFA composites based on electromagnetic (EM) parameter optimization and enhanced EM wave attenuation performance. The microwave absorption capacity of TiO2@C/CFA-2 composite is obviously better than that of CFA. It is confirmed that good impedance matching derived from the combination of TiO2@C and CFA is the main factor to achieve excellent microwave absorption. Moreover, the improved microwave absorption capabilities are closely related to multiple EM wave absorbing mechanisms including multiple reflections and scattering, dipolar and interfacial polarization, and conductivity loss. TiO2@C/CFA-2 possesses a maximum reflection loss (RL) of -43.18 dB at a low response frequency of 6.0 GHz. As the matching thickness is less than 2.0 mm, the maximum RL values can still exceed -20 dB, and at the same time, the wide effective absorption bandwidth (EAB) below -10 dB achieves 4.36 GHz at only 1.9 mm thickness. Our work confirms that the lightweight and high-performance TiO2@C/CFA composites are promising choices and offer a new approach to design and construct carbon-based microwave absorbents derived from biomass.

8.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35806202

RESUMEN

The sugarcane woolly aphid is one of the main pests of sugarcane worldwide. The Pinellia pedatisecta agglutinin (PPA) gene has been demonstrated to function towards aphid resistance in other crops. In our study, in order to investigate the PPA function towards aphid control in sugarcane and its underlying mechanism, the PPA gene was overexpressed in a sugarcane Zhongzhe 1 (ZZ1) cultivar in independent transgenic sugarcane lines. It was confirmed in this study that PPA transgenic sugarcane can resist aphids via detecting the aphids' development and tracing the survival number on PPA-transgenic sugarcane lines as well as PPA negative control lines. The mechanism of PPA lectin-associated defense against aphids was preliminarily explored. Stomatal patterning differences of sugarcane leaves between PPA-transgenic sugarcane lines and negative control lines were found. PPA overexpression led to an increase in stomata number and a decrease in stomata size that might have changed the transpiration status, which is critical for aphids' passive feeding. Moreover, the antioxidant enzyme, sugar, tannin and chlorophyll content in sugarcane leaves before and after aphid infestation was determined. The results indicated that PPA overexpression in sugarcane resulted in an increase in antioxidant enzyme activity and tannin content, as well as a reduction in the decline of certain sugars. These together may improve sugarcane resistance against the sugarcane woolly aphid.


Asunto(s)
Áfidos , Pinellia , Saccharum , Aglutininas , Animales , Animales Modificados Genéticamente , Antioxidantes , Saccharum/genética , Taninos
9.
Cell Immunol ; 352: 104113, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32331794

RESUMEN

Human placenta-derived mesenchymal stromal cells (hPMSCs) are promising candidates for the treatment of graft-versus-host disease (GVHD), which is associated with high IL-1ß levels. In this study, the effects of IL-1ß and hPMSCs on each other were investigated by analyzing the proportion of Th1, Th2 and CD4+IL-10+ T cells and PD-L1 expression, as well as the adhesion, migration, and proliferation of hPMSCs. The results showed that hPMSCs decreased IL-1ß levels and downregulated Th1/Th2 and Th1/CD4+IL-10+ T cells ratios in the GVHD model. The in vitro results revealed that IL-1ß strengthened the hPMSCs capacity to reduce the Th1/Th2 and Th1/CD4+IL-10+ T cell ratios, inhibited the adhesion and proliferation of hPMSCs and increased PD-L1 expression on hPMSCs via the JAK and NF-κB pathways. Overall, these findings suggested that hPMSCs alleviate GVHD by decreasing IL-1ß level and maintaining the balance among different T cell subsets. IL-1ß enhanced the ability of hPMSCs to balance different T cell subsets and inhibited hPMSCs adhesion and proliferation by regulating PD-L1 expression via the JAK and NF-κB pathways.


Asunto(s)
Antígeno B7-H1/inmunología , Interleucina-1beta/inmunología , Células Madre Mesenquimatosas/inmunología , Placenta/inmunología , Animales , Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Adhesión Celular/inmunología , Diferenciación Celular/inmunología , Movimiento Celular/inmunología , Proliferación Celular/fisiología , Células Cultivadas , Técnicas de Cocultivo , Femenino , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/metabolismo , Humanos , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Placenta/citología , Placenta/metabolismo , Embarazo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/inmunología , Células Th2/metabolismo
10.
Respir Res ; 21(1): 271, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33076910

RESUMEN

BACKGROUND: The role of the microbiota in the pathogenesis of chronic obstructive pulmonary disease (COPD) following exposure to ambient particulate matter (PM) is largely unknown. METHODS: Fifty-four male Sprague-Dawley rats were exposed to clean air, biomass fuel (BMF), or motor vehicle exhaust (MVE) for 4, 12, and 24 weeks. We performed pulmonary inflammation evaluation, morphometric measurements, and lung function analysis in rat lung at three different times points during exposure. Lung and gut microbial composition was assessed by 16S rRNA pyrosequencing. Serum lipopolysaccharide levels were measured and short-chain fatty acids in colon contents were quantified. RESULTS: After a 24-week PM exposure, rats exhibited pulmonary inflammation and pathological changes characteristic of COPD. The control and PM exposure (BMF and MVE) groups showed similar microbial diversity and composition in rat lung. However, the gut microbiota after 24 weeks PM exposure was characterized by decreased microbial richness and diversity, distinct overall microbial composition, lower levels of short-chain fatty acids, and higher serum lipopolysaccharide. CONCLUSION: Chronic exposure to ambient particulate matter induces gut microbial dysbiosis and metabolite shifts in a rat model of chronic obstructive pulmonary disease.


Asunto(s)
Disbiosis/inducido químicamente , Microbioma Gastrointestinal/efectos de los fármacos , Exposición por Inhalación/efectos adversos , Pulmón/efectos de los fármacos , Material Particulado/toxicidad , Enfermedad Pulmonar Obstructiva Crónica/inducido químicamente , Animales , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Disbiosis/sangre , Disbiosis/fisiopatología , Microbioma Gastrointestinal/fisiología , Pulmón/fisiopatología , Masculino , Material Particulado/administración & dosificación , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ratas , Ratas Sprague-Dawley
11.
BMC Bioinformatics ; 20(Suppl 25): 699, 2019 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-31874616

RESUMEN

BACKGROUND: The recognition of protein interaction sites is of great significance in many biological processes, signaling pathways and drug designs. However, most sites on protein sequences cannot be defined as interface or non-interface sites because only a small part of protein interactions had been identified, which will cause the lack of prediction accuracy and generalization ability of predictors in protein interaction sites prediction. Therefore, it is necessary to effectively improve prediction performance of protein interaction sites using large amounts of unlabeled data together with small amounts of labeled data and background knowledge today. RESULTS: In this work, three semi-supervised support vector machine-based methods are proposed to improve the performance in the protein interaction sites prediction, in which the information of unlabeled protein sites can be involved. Herein, five features related with the evolutionary conservation of amino acids are extracted from HSSP database and Consurf Sever, i.e., residue spatial sequence spectrum, residue sequence information entropy and relative entropy, residue sequence conserved weight and residual Base evolution rate, to represent the residues within the protein sequence. Then three predictors are built for identifying the interface residues from protein surface using three types of semi-supervised support vector machine algorithms. CONCLUSION: The experimental results demonstrated that the semi-supervised approaches can effectively improve prediction performance of protein interaction sites when unlabeled information is involved into the predictors and one of them can achieve the best prediction performance, i.e., the accuracy of 70.7%, the sensitivity of 62.67% and the specificity of 78.72%, respectively. With comparison to the existing studies, the semi-supervised models show the improvement of the predication performance.


Asunto(s)
Proteínas/química , Algoritmos , Secuencia de Aminoácidos , Aminoácidos/química , Fenómenos Bioquímicos , Secuencia Conservada , Entropía , Máquina de Vectores de Soporte
12.
Toxicol Appl Pharmacol ; 366: 1-9, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30660475

RESUMEN

Peniciketal A (Pe-A), a spiroketal compound, is isolated from the saline soil-derived fungus Penicillium raistrickii. However, the underlying molecular mechanistic basis for the effects of Pe-A on leukemia is poorly understood. Here, we investigated that Pe-A reduced cell proliferation in three leukemia cell lines (THP-1, K562 and HL60). Importantly, Pe-A showed little cytotoxicity in primary mouse embryonic fibroblast (MEF) cells in a long-duration treatment. For the mechanistic research, we identified 3449 differentially expressed Pe-A-induced proteins through liquid chromatography-tandem mass spectrometry (LC-MS/MS) with TMT label in THP-1 cells. Results showed that many identified proteins were involved in apoptosis and/or autophagy. Then, we confirmed that Pe-A induced not only apoptosis via the mitochondrial pathway but also cytoprotective autophagy by activating the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway indeed. In addition, Pe-A also arrested the cell cycle at the G0-G1 phase by regulating the expressions of checkpoint protein. Collectively, these results provide new insights into the mechanisms that Pe-A may target autophagy-related or apoptosis-related pathways to suppress the development of human leukemia.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular , Leucemia/tratamiento farmacológico , Piranos/farmacología , Compuestos de Espiro/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/efectos de los fármacos , Proteínas Relacionadas con la Autofagia/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Células HL-60 , Humanos , Células K562 , Leucemia/metabolismo , Leucemia/patología , Ratones , Proteómica/métodos , Piranos/toxicidad , Transducción de Señal/efectos de los fármacos , Compuestos de Espiro/toxicidad , Células THP-1 , Serina-Treonina Quinasas TOR/metabolismo , Espectrometría de Masas en Tándem
13.
Langmuir ; 34(51): 15854-15863, 2018 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-30508484

RESUMEN

Lightweight and compatible metal-organic framework (MOF)-derived carbon-based composites are widely used in electromagnetic (EM) absorption. Their combination with laminated TiO2-C (derived from Ti3C2T x) is expected to further strengthen the EM attenuation ability. Herein, novel laminated Co/TiO2-C hybrids were derived from Ti3C2T x/Co-MOF using heat treatment. Compared with pristine MOF-derived carbon-based composites, the EM absorption ability of Co/TiO2-C was improved by multiple reflections between multilayered microstructures and the improved polarization loss (due to the heterogeneous interfaces, residual defects, and dipole polarization) and the strengthened conductivity loss caused by the carbon layers. Specifically, for the Co/TiO2-C hybrids at thicknesses of 3.0 and 2.0 mm, the optimal reflection loss (RL) was -41.1 dB at 9.0 GHz and -31.0 dB at 13.9 GHz, with effective bandwidths (RL ≤ -10 dB) of 3.04 and 4.04 GHz, respectively. This study will underline the preparation of carbon-based absorbing materials starting from MXene/MOF hybrids.

14.
J Nanosci Nanotechnol ; 18(7): 5113-5118, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442702

RESUMEN

One-dimensional (1D) semiconductor ZnO nanowires have been successfully synthesized by a novel soft-chemical hydrothermal method with allylpolyethoxy amino carboxylate (AA-APEA) at low temperature. Their structure and properties have been characterized by a series of techniques, including X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM). It was found that ZnO nanowires with diameters around 50 nm and lengths up to about several micrometers are well-distributed. The photocatalytic activity toward degradation of methylene blue (MB) aqueous solution under ultraviolet (UV) was investigated and the results showed that the ZnO nanowires exhibit a markedly higher photoactivity compared to the ZnO nanoparticles which were obtained without AA-APEA polymer assistant, and it can be ascribed to the special 1D morphology of the ZnO nanowires. In particular, the rate of degradation of the ZnO nanowires was 11 times faster than that of ZnO nanoparticles. In addition, the ZnO nanowires could be easily recycled in UV photocatalytic activity. These observations could promote new applications of photocatalyst for wastewater treatment utilizing oxide semiconductor nanostructures.

15.
Respir Res ; 18(1): 143, 2017 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-28743263

RESUMEN

BACKGROUND: Ambient particulate matter exposure has been shown to increase the risks of respiratory diseases. However, the role of the lung microbiome and the immune response to inhaled particulate matter are largely unexplored. We studied the influence of biomass fuel and motor vehicle exhaust particles on the lung microbiome and pulmonary immunologic homeostasis in rats. METHODS: Fifty-seven Sprague-Dawley rats were randomly divided into clean air (CON), biomass fuel (BMF), and motor vehicle exhaust (MVE) groups. After a 4-week exposure, the microbial composition of the lung was assessed by 16S rRNA pyrosequencing, the structure of the lung tissue was assessed with histological analysis, the phagocytic response of alveolar macrophages to bacteria was determined by flow cytometry, and immunoglobulin concentrations were measured with commercial ELISA kits. RESULTS: There was no significant difference in lung morphology between the groups. However, the BMF and MVE groups displayed greater bacterial abundance and diversity. Proteobacteria were present in higher proportions in the MVE group, and 12 bacterial families differed in their relative abundances between the three groups. In addition, particulate matter exposure significantly increased the capacity of alveolar macrophages to phagocytose bacteria and induced changes in immunoglobulin levels. CONCLUSION: We demonstrated that particulate matter exposure can alter the microbial composition and change the pulmonary immunologic homeostasis in the rat lung.


Asunto(s)
Bacterias/efectos de los fármacos , Biomasa , Fuentes Generadoras de Energía , Pulmón/efectos de los fármacos , Macrófagos Alveolares/efectos de los fármacos , Material Particulado/toxicidad , Emisiones de Vehículos/toxicidad , Animales , Bacterias/clasificación , Bacterias/inmunología , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Interacciones Huésped-Patógeno , Inmunoglobulinas/inmunología , Exposición por Inhalación , Pulmón/inmunología , Pulmón/microbiología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/microbiología , Masculino , Fagocitosis/efectos de los fármacos , Ratas Sprague-Dawley , Ribotipificación , Factores de Tiempo
16.
Chemistry ; 23(18): 4336-4343, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28178382

RESUMEN

High-quality double-shelled TiO2 hollow spheres (DHS-Ti) assembled with TiO2 nanosheets have been synthesized for the first time through a simple hydrothermal treatment of sSiO2 @TiO2 (TiO2 -coated solid SiO2 spheres). The double-shelled structure shows a high BET surface area up to 417.6 m2 g-1 . Anatase DHS-Ti of high crystallinity can be obtained without structural collapse by calcination treatment. The effects of cetyl trimethylammonium bromide (CTAB) concentration, pH, and hydrothermal reaction temperature have also been investigated with a series of contrast experiments. A formation mechanism involving the in situ growth of amorphous TiO2 nanosheets followed by the redeposition of dissolved silica species is proposed. Lastly, the DHS-Ti forming strategy can be extended as a general strategy to fabricate various morphological hollow nanostructures and double-shelled Pt nanocatalysts by rationally selecting functional sSiO2 nanoparticles as core materials. This work could open up a new strategy for controllable synthesis of complex hollow structures and other functional materials.

17.
Langmuir ; 33(11): 2698-2708, 2017 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-28248116

RESUMEN

A novel strategy was reported for the fabrication of yolk-shell magnetic MFSVmS-Au nanocomposites (NCs) consisting of double-layered ellipsoidal mesoporous silica shells, numerous sub-4 nm Au nanoparticles (NPs), and magnetic Fe central cores. The hierarchical FSVmS NCs with ellipsoidal α-Fe2O3@mSiO2/mSiO2 as yolks/shells were first prepared through the facile sol-gel template-assisted method, and plenty of extremely stable ultrafine Au NPs were postencapsulated within interlayer cavities through the unique deposition-precipitation method mediated with Au(en)2Cl3 compounds. Notably, ethylenediamine ligands were used to synthesize the stable cationic complexes, [Au(en)2]3+, that readily underwent the deprotonation reaction to chemically modify negatively charged mesoporous silica under alkaline conditions. The subsequent two-stage programmed hydrogen annealing initiated the in situ formation of Au NPs and the reduction of α-Fe2O3 to magnetic Fe, where the synthesized Au NPs were highly resistant to harsh thermal sintering even at 700 °C. Given its structural superiority and magnetic nature, the MFSVmS-Au was demonstrated to be a highly efficient and recoverable nanocatalyst with superior activity and reusability toward the reduction of 4-nitrophenol to 4-aminophenol, and the pristine morphology was retained after six recycling tests.

18.
Des Monomers Polym ; 20(1): 397-405, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29491811

RESUMEN

Water-soluble monomer APEG-PG-(OH)n were produced and the Structure of APEG-PG-(OH)5 were identified by 1H-NMR. APEG-PG-(OH)n were copolymerized with maleic anhydride (MA) to synthesize no phosphate and nitrogen free calcium carbonate inhibitor MA/APEG-PG-(OH)n. The structure and thermal property of MA/APEG-PG-(OH)5 were characterized and measured by 1H-NMR, GPC and TGA. The observation shows that the dosage and n value of MA/APEG-PG-(OH)n plays an important role on CaCO3 inhibition. MA/APEG-PG-(OH)5 displays superior ability to inhibit the precipitation of calcium carbonate, with approximately 97% inhibition at a level of 8 mg/L. The effect on formation of CaCO3 was investigated with combination of SEM and XRD analysis.

19.
Heliyon ; 10(12): e32876, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38975175

RESUMEN

Introduction: The high incidence of wasp stings have been causing a variety of injuries in China, but systemic complications are rarely reported. Case presentation: A 59-year-old man was severely attacked by wasps. He developed an acute onset of right hemiplegia and chest distress and was admitted to our emergency department 13 hours after being attacked. Various abnormal signals were found by biochemical tests. Magnetic resonance venography of head demonstrated that the superior sagittal sinus was not visible, indicating cerebral venous sinus thrombosis. Magnetic resonance imaging showed abnormal signals in the left frontal lobe, parietal lobe, and thalamus, indicating venous cerebral infarction and hemorrhage, coupled with subarachnoid hemorrhage. The patient was diagnosed with a rare combination of cerebral venous sinus thrombosis, cerebral venous infarction, and multi-organ dysfunction following hornet stings. After undergoing systematic treatment including blood perfusion, blood dialysis, anti-inflammatory hormone therapy, antiallergic medication, antibiotic use, and anticoagulation treatment, the patient showed significant improvement in limb muscle strength and dizziness symptoms. However, the patient developed irreversible kidney damage and is currently dependent on renal replacement therapy. Conclusions: This case highlights the serious systemic consequences that can occur following multiple wasp stings, including rare complications such as venous sinus thrombosis leading to cerebral infarction and renal failure. Early intervention with blood perfusion, hemodialysis, and plasmapheresis, in addition to general treatment, may help prevent permanent organ damage in patients with a large number of wasp stings.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38949986

RESUMEN

Background: Lung adenocarcinoma (LUAD) remains heterogeneous in the prognosis of patients; oxidative stress (OS) has been widely linked to cancer progression. Therefore, it is necessary to explore the prognostic value of the OS-associated genes in LUAD. Methods: An OS-associated prognostic signature was developed using the Cox regression and random forest model in The Cancer Genome Atlas-LUAD dataset. Kaplan-Meier (K-M) survival curve and time-dependent receiver operating characteristic (tROC) curves were applied to evaluate and validate the predictive accuracy of this signature among the training and testing cohorts. A nomogram was constructed and also verified by the concordance index (C-index), calibration curves, and tROC curves, respectively. ESTIMATE algorithm and CIBERSORT algorithms were conducted to explore the signature's immune characteristics. Core target genes of the prognostic signature were identified in the protein-protein interaction network. Results: A six OS-associated prognostic gene signature (CDC25C, ERO1A, GRIA1, TERT, CAV1, BDNF) was developed. The tROC and K-M survival curves in the training and testing cohorts revealed that the signature had good and robust predictive capability to predict the overall survival of LUAD patients. Meanwhile, the risk score was an independent prognostic factor influencing patients' overall survival. The results of the C-index (0.714), calibration curves, and the 1-, 2-, and 3-year tROC curves (area under the curve = 0.703, 0.737, and 0.723, respectively) suggested that the nomogram had good predictive efficacy and prognostic value for LUAD. Then, the authors found that the high-risk group may be depletion or loss of antitumor function of immune cells. Finally, 10 core genes of the signature were predicted. Conclusion: Their study may provide a novel understanding for the identification of prognostic stratification in LUAD patients, as well as the regulation of OS-associated genes in LUAD progression.

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