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1.
J Hazard Mater ; 467: 133752, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38350320

RESUMO

A remarkably efficient and affordable Fe/Cu bimetallic catalyst featuring a substantial light energy utilization and compatibility with a sizable substrate was developed for Fenton-like reactions aimed at pollutant control. Specifically, a novel strategy was employed to synthesize high-density metal sites (Fe:Cu ≈ 3:1) robustly embedded on polyethylene/polyethylene terephthalate nonwoven fabric (PE/PET NWF) via radiation-induced graft polymerization (RIGP) and subsequent chemical modification, labeled as Fe/Cu-PPAO. Its high effectiveness was demonstrated by degrading 50 mg/L of tetracycline hydrochloride within 30 min in the presence of H2O2 under simulate sunlight irradiation. It was investigated that amidoxime groups regulated the optical gaps and HOMO-LUMO gaps of metal ions to enable the absorption of a broader spectrum light while the Cu2+ facilitated the transfer of electrons between the bimetal ions to achieve an improved reaction path. Furthermore, X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations further revealed its special complex state and delicate electronic structure between bimetal ions and amidoxime groups. Our study offers a new strategy to synthesize high-density bimetallic sites catalyst for environmental remediation and pushes forward insight into understanding the catalytic mechanism of bimetallic Fenton-like catalysts.

2.
Genome Med ; 16(1): 9, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38225592

RESUMO

BACKGROUND: Detecting human cancers through cell-free DNA (cfDNA) in blood is a sensitive and non-invasive option. However, capturing multiple forms of epigenetic information remains a technical and financial challenge. METHODS: To address this, we developed multimodal epigenetic sequencing analysis (MESA), a flexible and sensitive approach to capturing and integrating a diverse range of epigenetic features in cfDNA using a single experimental assay, i.e., non-disruptive bisulfite-free methylation sequencing, such as Enzymatic Methyl-seq. MESA enables simultaneous inference of four epigenetic modalities: cfDNA methylation, nucleosome occupancy, nucleosome fuzziness, and windowed protection score for regions surrounding gene promoters and polyadenylation sites. RESULTS: When applied to 690 cfDNA samples from 3 colorectal cancer clinical cohorts, MESA's novel modalities, which include nucleosome fuzziness, and genomic features, including polyadenylation sites, improve cancer detection beyond the traditional epigenetic markers of promoter DNA methylation. CONCLUSIONS: Together, MESA stands as a major advancement in the field by utilizing comprehensive and complementary epigenetic profiles of cfDNA for effective non-invasive cancer detection.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Colorretais , Humanos , Ácidos Nucleicos Livres/genética , Nucleossomos/genética , Metilação de DNA , Epigênese Genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Biomarcadores Tumorais/genética
3.
Sci Total Environ ; 838(Pt 1): 155835, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35550904

RESUMO

The surface interactions of iron (hydr)oxides with various environmental chemicals play a vital role in controlling their environmental transport and fate. As a bioessential element, phosphorus and its biogeochemical cycling are usually controlled by its adsorption on iron (hydr)oxides. Photoreductive dissolution of iron (hydr)oxides can change their surface structure and properties, but its influence on the adsorption of phosphate remains unknown. Here, an enhanced removal of phosphate during the photoreductive dissolution of ferrihydrite (Fh) was investigated. The Kd value of phosphate adsorption on Fh under light irradiation is evidently larger than that in the dark (21 vs 13 L/g). Zeta potential determination in combination with X-ray photoelectron spectroscopy analysis suggested that the released Fe2+ from Fh surface during photoreductive dissolution can be oxidized to Fe3+, which then co-adsorb with phosphate back to Fh surface, enhancing the immobilization of phosphate on Fh. In situ ATR-FTIR results disclosed that light irradiation could further facilitate the formation of ternary complexes and surface precipitation on Fh, even after the increment of phosphate adsorption becoming negligible in the dark, and the relative content of surface precipitation increased evidently. The desorption ratio of phosphate from the irradiated Fh sample was reduced, which should be attributed to a high content of surface precipitation that can tightly bind phosphate on Fh. The findings of this study highlight an important yet previously unappreciated pathway that light irradiation can enhance the immobilization of phosphate on iron (hydr)oxides.


Assuntos
Compostos Férricos , Fosfatos , Adsorção , Compostos Férricos/química , Ferro , Óxidos/química , Fosfatos/química , Solubilidade
4.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3938-3944, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893592

RESUMO

The aim of this paper was to observe the anti-inflammatory action and mechanism of Lonicerae Japonicae Flos extract and Lonicerae Flos extract in xylene-induced ear swelling experiment and lipopolysaccharide(LPS)-induced RAW264.7 cell inflammatory model. In vivo, xylene-induced mouse auricle swelling model was used to detect the auricle swelling degree and swelling inhibition rate of Lonicerae Japonicae Flos extract and Lonicerae Flos extract; the pathological changes of mice auricle were observed by hematoxylin eosin(HE) staining. In vitro, RAW264.7 inflammatory cell model was induced by LPS, where the cytotoxic effects of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on RAW264.7 cells were detected by CCK-8 method; Griess method was used to detect the effect of Lonicerae Japonicae Flos extract and Lonicerae Flos extract on nitric oxide(NO) production, and ELISA method was used to detect the content of inflammatory factors interleukin-6(IL-6), IL-1ß, and tumor necrosis factor-α(TNF-α). At last, Western blot was used to detect the protein changes of cyclooxygenase 1(COX1), COX2 and inducible nitric oxide synthetase(iNOS) for RAW264.7 cells. The results showed that both Lonicerae Japonicae Flos extract and Lonicerae Flos extract could significantly inhibit the degree of auricle swelling caused by xylene in mice and the inhibition rate was positively correlated with the drug dose. Furthermore, both of them could reduce the infiltration of lymphocytes and neutrophils in mouse ear tissues. For in vitro experiments, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract inhibited NO secretion in RAW264.7 cells, down-regulated the release of IL-1ß, IL-6 and TNF-α, and down-regulated iNOS protein and COX2, NF-κB p65 protein content. In conclusion, both Lonicerae Japonicae Flos extract and Lonicerae Flos extract have good anti-inflammatory effect, and the mechanism may be related with the inhibition of NF-κB signaling pathway.


Assuntos
Lonicera , Animais , Anti-Inflamatórios , Lipopolissacarídeos , Camundongos , Extratos Vegetais
5.
J Nanosci Nanotechnol ; 20(9): 5555-5562, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32331134

RESUMO

The ternary mesoporous MgFeAl oxide (MgFeAlO) material was designed and prepared using glucose as a soft template by calcination of its MgFeAl hydrotalcite precursor. The MgFeAlO showed significantly better Cr(VI) adsorption performance than binary MgAlO. The effect of Fe3+ on Cr(VI) removal in simulated wastewater was studied by researching the microstructure, adsorption properties and mechanism of the material. The results showed that the addition of Fe3+ affected the microstructure of MgAlO, where the partial substitution of Al3+ by Fe3+ into the host layers resulted in an increase in the interlayer region and specific area (SBET) as well as an enlargement in mesoporous feature into the MgFeAlO. The Cr(VI) adsorption process, taking place by the reconstruction of the MgFeAlO oxide with water (memory effect) companying with the intercalation of CrO2-4 anions, was much more efficient than that occurring in the binary MgAlO. MgFeAlO's adsorption of Cr(VI) follows the pseudo-second-order model and it is controlled by intra particle diffusion. The adsorption isotherm was better fitted by the Langmuir model, suggesting that the Cr(VI) adsorption was a monolayer adsorption onto the homogeneous support surface. All thermodynamic and kinetic calculations suggested that the Cr(VI) adsorption process on the MgFeAlO was of chemisorption nature, in which activation energy (Ea) and enthalpy change (ΔH) were 30.01 and 193.58 kJ·mol-1, respectively.

6.
Carbohydr Polym ; 234: 115891, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070511

RESUMO

An efficient and bio-based alginate pillared hydrotalcite (SA@LDHs) was fabricated via calcination-reconstruction manner with sodium alginate (SA) and hydrotalcite (LDHs-C), and used as novel flame retardant for polypropylene (PP). The morphologies and combustion properties of SA@LDHs and its hybrid with PP composites (PP/SA@LDHs) had been characterized by SEM, TGA, cone calorimetry, LOI and UL-94 measurements. With 30 wt% loading, the SA@LDHs achieved a LOI value of 30.9 % and a UL-94 V-0 rating, whereas the LDHs-C exhibited only LOI value of 27.6 % and a UL-94 V-1 rating. The peak heat release rate, total heat release and total smoke production of PP/SA@LDHs were 260.8 kW m-2, 61.3 MJ m-2 and 8.2 m2, respectively, which presented declines of 69.2 %, 42.8 % and 32.2 % compared with those of Neat PP. These improvements could be attributed to the presence of the radical-trapping effect of SA, which leading to promote PP chains to participate in the carbonization process.

7.
Epigenomics ; 11(15): 1717-1732, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625763

RESUMO

Aim: Breast cancer histologic grade (HG) is a well-established prognostic factor. This study aimed to select methylomic biomarkers to predict breast cancer HGs. Materials & methods: The proposed algorithm BioDog firstly used correlation bias reduction strategy to eliminate redundant features. Then incremental feature selection was applied to find the features with a high HG prediction accuracy. The sequential backward feature elimination strategy was employed to further refine the biomarkers. A comparison with existing algorithms were conducted. The HG-specific somatic mutations were investigated. Results & conclusions: BioDog achieved accuracy 0.9973 using 92 methylomic biomarkers for predicting breast cancer HGs. Many of these biomarkers were within the genes and lncRNAs associated with the HG development in breast cancer or other cancer types.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Metilação de DNA/genética , Algoritmos , Bases de Dados Genéticas , Feminino , Humanos , Mutação/genética
8.
J Nanosci Nanotechnol ; 19(11): 7476-7486, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039916

RESUMO

The microcapsule nanoparticles were prepared by in-situ copolymerization of hydrotalcites (MAH) with the polymer (MF, PF, PS and PU) monomers, respectively, where the MF-wrapped MAH (MAH@MF) had the best monodispersity. The composites of the microcapsules and EVA were prepared by incorporating the microcapsule nanoparticles into ethylene vinyl acetate (EVA), respectively. To further understand the intrinsic correlation between microcapsule fillers and EVA matrix, molecular dynamics (MD) simulation was introduced to qualitatively analyze the contribution of microcapsule fillers on improving compatibility and mechanical properties of the EVA matrix. The compatibility of microcapsule nanoparticles with EVA matrix were detected in sequence through SEM, DSC and tensile strength tests. And the combustion, thermal behavior and flame retardance were also characterized by TG analyses as well as LOI and UL-94 level. As a result, the MAH@MF filler had the best performances in improving the flame retardancy and mechanical properties among the microcapsule fillers, attributed to high compatibility of the MAH@MF and EVA matrix, which made uniform distribution of the MAH@MF filler due to the reciprocity of triazine functional ring with vinyl acetate linkages.

9.
Ecotoxicol Environ Saf ; 172: 423-431, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30735974

RESUMO

The photocatalytic performance of layered double hydroxides (LDH) is usually confined to the slow interface mobility and high recombination rate of photogenerated electron-hole pairs in material. To overcome the low photocatalytic efficiency, novel Ag2O/Ag decorated LDH (LDH-Ag2O/Ag) was successfully synthesized by depositing Ag2O on the surface of LDH and then converted to Ag° nanoparticles in the right position after heat treatment. The as-synthesized LDH-Ag2O/Ag composites were characterized by Powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL) and transient photocurrent (TPC) analysis. Compared with virgin LDH, the photocatalytic activities of LDH-Ag2O/Ag composites were enhanced significantly. The optimum photocatalytic efficiency of LDH-Ag10 (0.0184 min-1) was nearly 46 times higher than that of virgin LDH (0.0004 min-1). The result of active species trapping experiments indicated that •OH, h+, and •O2- have an effect on the TC degradation, where •OH played the predominant role during the photocatalytic process. The possible photocatalytic mechanisms involving the charge transfer pathway and reactive species generation during the process of TC degradation were also discussed. The improved photocatalytic activity of LDH-Ag2O/Ag could be attributed to the synergetic effect between LDH and Ag2O/Ag that extended visible light range and reduced photogenerated charge carriers recombination.


Assuntos
Luz , Óxidos/química , Compostos de Prata/química , Tetraciclina/química , Antibacterianos/química , Catálise , Hidróxidos/química , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Difração de Raios X
10.
J Mater Chem B ; 7(2): 265-276, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254551

RESUMO

The clinical application of SN38 (7-ethyl-10-hydroxy-camptothecin) is severely restricted by its extremely low water solubility. Nanoaggregates formed by amphiphilic SN38 prodrugs have been widely used for the delivery of SN38. In this study, we used a hydrophobized SN38 prodrug, rather than a typical SN38 amphiphile, to construct rod-shaped nanoaggregates for efficient SN38 delivery. The hydrophobized SN38 was synthesized by conjugating SN38 with oleic acid using disulfanyl-ethyl carbonate as the linker. Interestingly, the resulting prodrug self-assembled into nanorods with high drug loading capacity (45%) and colloidal stability. Moreover, these nanorods displayed an impressively high redox-sensitivity to release 100% SN38 within 1 h in 10 mM DTT, versus 1% in phosphate buffer (pH 7.4). The efficient drug release resulted in an uncompromised in vitro cytotoxicity, which was comparable to free SN38 and nearly 93-fold more potent than CPT-11. Most importantly, these novel prodrug nanoaggregates exhibited potent antitumor activity in the CT26 colorectal cancer xenograft. The nanoaggregates of such redox-hypersensitive hydrophobized SN38 represent an effective alternative strategy for developing novel SN38 nanomedicines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Irinotecano/farmacologia , Nanopartículas/uso terapêutico , Nanotubos , Pró-Fármacos/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Irinotecano/análogos & derivados , Irinotecano/síntese química , Masculino , Camundongos Endogâmicos BALB C , Nanomedicina , Solubilidade
11.
J Nanosci Nanotechnol ; 18(12): 8225-8231, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189941

RESUMO

In order to enhance the adsorption capacity of hydrotalcite material for heavy metal ions, the LDH/CMC composite was prepared by a simple hydrothermal method. The XRD pattern showed that the presence of CMC has no obvious influence on the crystal structure of hydrotalcites. The FT-IR and UV-vis DRS analyses showed that the CMC functionalized surface has been obtained. The SEM and BET/BJH showed that the morphologies, textural and surface chemical properties of LDH were affected remarkably after the introduction of CMC. The weight percentage of CMC in the LDH/CMC composite was estimated to be about 17.4%. The adsorption experiments showed the LDH/CMC composite exhibited high efficiency in the Cu(II) removal at pH > 6.5, affording Cu(II) removal rates of 92.3%. The results demonstrated that the LDH/CMC composite was a suitable adsorbent for Cu(II)-contaminated wastewater treatment.

12.
J Environ Sci (China) ; 60: 14-23, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29031441

RESUMO

TiO2 in anatase crystal phase is a very effective catalyst in the photocatalytic oxidation of organic compounds in water. To improve its photocatalytic activity, the Ti-coating MgAl hydrotalcite (Ti-MgAl-LDH) was prepared by chemical vapor deposition (CVD) method. Response surface method (RSM) was employed to evaluate the effect of Ti species coating parameters on the photocatalytic activity, which was found to be affected by the furnace temperature, N2 flow rate and influx time of precursor gas. Application of RSM successfully increased the photocatalytic efficiency of the Ti-MgAl-LDH in methylene blue photodegradation under UV irradiation, leading to improved economy of the process. According to the results from X-ray diffraction, scanning electron microscopy, Brunner-Emmet-Teller and Barrett-Joyner-Hallender, thermogravimetric and differential thermal analysis, UV-vis diffuse reflectance spectra analyses, the Ti species (TiO2 or/and Ti4+) were successfully coated on the MgAl-LDH matrix. The Ti species on the surface of the Ti-MgAl-LDH lead to a higher photocatalytic performance than commercial TiO2-P25. The results suggested that CVD method provided a new approach for the industrial preparation of Ti-coating MgAl-LDH material with good photocatalytic performances.


Assuntos
Hidróxido de Alumínio/química , Compostos Azo/química , Hidróxido de Magnésio/química , Eliminação de Resíduos Líquidos/métodos , Corantes/química , Fotólise , Titânio
13.
J Nanosci Nanotechnol ; 16(3): 3122-31, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27455772

RESUMO

The hydrotalcite of Mg6Fe2(OH)16CO3 x 4.5H2O were synthesized using urea method by adjusting the initial pH and urea amount in the reaction solution. The results showed that the co-precipitation of Mg2+ with Fe3+ cations formed Mg-Fe LDH occurring at pH 8.48-9.35. The pH played a crucial role in the Mg-Fe LDH precipitation by controlling urea/Fe3+ molar ratio in the reaction solution at 105 degrees C. The optimized urea/Fe3+ molar ratio was 12.0, where the relative yield of the Mg-Fe LDH was 80.0% and the Mg-Fe LDH was highly crystalline with small particle sizes (1-2 µm). The affinity of the Mg-Fe mixed oxide (Mg-Fe LDO) with Cr(VI) was studied as a function of contact time, initial pH, temperature of the solutions and calcined time of Mg-Fe LDH. The adsorption conditions were optimized using response surface methodology. The maximum adsorption capacity of 38.86 mg/g was achieved at 85 min with the conditions of initial pH 5.5, temperature 55 degrees C and calcined time 4 h. It was concluded that the Mg-Fe LDO can be used as an adsorbent to removal Cr(VI) in aqueous solutions.


Assuntos
Hidróxido de Alumínio/química , Cromo/química , Ferro/química , Hidróxido de Magnésio/química , Magnésio/química , Ureia/química , Adsorção , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Temperatura , Difração de Raios X
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