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1.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 4): 375-377, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38584728

RESUMO

The structure of (S)-5-(3-acetyl-5-chloro-2-ethoxy-6-fluorophenyl)-2-oxazolidinone, C13H13ClFNO4, at 100 K has monoclinic (P21) symmetry. The compound has a polymeric structure propagated by a screw axis parallel to the b axis with N-H⋯O hydrogen bonding. It is of inter-est with respect to efforts in the synthesis of a candidate anti-cancer drug, parsaclisib.

2.
Environ Sci Pollut Res Int ; 31(17): 25202-25215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38466381

RESUMO

Laccase immobilized and cross-linked on Fe3S4/earthworm-like mesoporous SiO2 (Fe3S4/EW-mSiO2) was used to degrade methoxychlor (MXC) in aqueous environments. The effects of various parameters on the degradation of MXC were determined using free and immobilized laccase. Immobilization improved the thermal stability and reuse of laccase significantly. Under the conditions of pH 4.5, temperature 40 °C, and reaction time 8 h, the degradation rate of MXC by immobilized laccase reached a maximum value of 40.99% and remained at 1/3 of the original after six cycles. The excellent degradation performance of Fe3S4/EW-mSiO2 was attributable to the pyrite (FeS2) impurity in Fe3S4, which could act as an electron donor in reductive dehalogenation. Sulfide groups and Fe2+ reduced the activation energy of the system resulting in pyrite-assisted degradation of MXC. The degradation mechanism of MXC in aqueous environments by laccase immobilized on Fe3S4/EW-mSiO2 was determined via mass spectroscopy of the degradation products. This study is a new attempt to use pyrite to support immobilized laccase degradation.


Assuntos
Ferro , Metoxicloro , Oligoquetos , Animais , Metoxicloro/química , Enzimas Imobilizadas/química , Lacase/metabolismo , Dióxido de Silício/química , Oligoquetos/metabolismo , Sulfetos
3.
Environ Res ; 248: 118312, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38295971

RESUMO

Overuse of chlorinated disinfectants leads to a significant accumulation of disinfection by-products. Trichloroacetic acid (TCA) is a typical carcinogenic disinfection by-product. The efficacy of the conventional degradation process is reduced by the complex nature of its structure, causing a yearly increase in its prevalence within the ecological environment and consequent infliction of significant harm. In this paper, TCA was chosen as the research subject, Fe/Ni bimetallic nanoparticles were employed as the reducing catalyst, ZIF-8@HMON as the catalytic carrier combined with Fe/Ni nanoparticles, and peroxymonosulfate (PMS) was introduced to construct the reducing-advanced oxidation synergistic system and investigated the effect of this system on the degradation performance and degradation pathway of TCA. Various characterization techniques, including TEM, SEM, XRD, FT-IR, XPS, BET, were employed to investigate the morphology, element composition and structure of composite materials analysis. Moreover, the conditions for TCA degradation can be optimized by changing the experimental environment. The results showed that 25 mg of composite catalyst (mole ratio Fe: Ni = 1:1) and 10 mg of PMS effectively degraded TCA within 20-80 mg/L range at pH = 3 and 55 °C, achieving maximum degradation within 20 min. Finally, the potential pathways of TCA degradation were analyzed using EPR and LC-MS, and the corresponding reaction mechanisms were proposed.


Assuntos
Nanopartículas , Ácido Tricloroacético , Espectroscopia de Infravermelho com Transformada de Fourier , Peróxidos/química , Nanopartículas/química
4.
BMC Med ; 21(1): 491, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38082312

RESUMO

BACKGROUND: Major psychiatric disorders such as schizophrenia (SCZ) and bipolar disorder (BPD) are complex genetic mental illnesses. Their non-Mendelian features, such as those observed in monozygotic twins discordant for SCZ or BPD, are likely complicated by environmental modifiers of genetic effects. 5-Hydroxymethylcytosine (5hmC) is an important epigenetic mark in gene regulation, and whether it is linked to genetic variants that contribute to non-Mendelian features remains largely unexplored. METHODS: We combined the 5hmC-selective chemical labeling method (5hmC-seq) and whole-genome sequencing (WGS) analysis of peripheral blood DNA obtained from monozygotic (MZ) twins discordant for SCZ or BPD to identify allelic imbalances in hydroxymethylome maps, and examined association of allele-specific hydroxymethylation (AShM) transition with disease susceptibility based on Bayes factors (BF) derived from the Bayesian generalized additive linear mixed model. We then performed multi-omics integrative analysis to determine the molecular pathogenic basis of those AShM sites. We finally employed luciferase reporter, CRISPR/Cas9 technology, electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), PCR, FM4-64 imaging analysis, and RNA sequencing to validate the function of interested AShM sites in the human neuroblastoma SK-N-SH cells and human embryonic kidney 293T (HEK293T) cells. RESULTS: We identified thousands of genetic variants associated with AShM imbalances that exhibited phenotypic variation-associated AShM changes at regulatory loci. These AShM marks showed plausible associations with SCZ or BPD based on their effects on interactions among transcription factors (TFs), DNA methylation levels, or other epigenomic marks and thus contributed to dysregulated gene expression, which ultimately increased disease susceptibility. We then validated that competitive binding of POU3F2 on the alternative allele at the AShM site rs4558409 (G/T) in PLLP-enhanced PLLP expression, while the hydroxymethylated alternative allele, which alleviated the POU3F2 binding activity at the rs4558409 site, might be associated with the downregulated PLLP expression observed in BPD or SCZ. Moreover, disruption of rs4558409 promoted neural development and vesicle trafficking. CONCLUSION: Our study provides a powerful strategy for prioritizing regulatory risk variants and contributes to our understanding of the interplay between genetic and epigenetic factors in mediating SCZ or BPD susceptibility.


Assuntos
Esquizofrenia , Gêmeos Monozigóticos , Humanos , Teorema de Bayes , Alelos , Gêmeos Monozigóticos/genética , Células HEK293 , Metilação de DNA/genética , Esquizofrenia/genética , Predisposição Genética para Doença , Epigênese Genética/genética
6.
Microsc Microanal ; 29(Supplement_1): 794-795, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37613417
8.
Adv Mater ; 35(38): e2208230, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37162379

RESUMO

Nanocomposites containing nanoscale materials offer exciting opportunities to encode nanoscale features into macroscale dimensions, which produces unprecedented impact in material design and application. However, conventional methods cannot process nanocomposites with a high particle loading, as well as nanocomposites with the ability to be tailored at multiple scales. A composite architected mesoscale process strategy that brings particle loading nanoscale materials combined with multiscale features including nanoscale manipulation, mesoscale architecture, and macroscale formation to create spatially programmed nanocomposites with high particle loading and multiscale tailorability is reported. The process features a low-shrinking (<10%) "green-to-brown" transformation, making a near-geometric replica of the 3D design to produce a "brown" part with full nanomaterials to allow further matrix infill. This demonstration includes additively manufactured carbon nanocomposites containing carbon nanotubes (CNTs) and thermoset epoxy, leading to multiscale CNTs tailorability, performance improvement, and 3D complex geometry feasibility. The process can produce nanomaterial-assembled architectures with 3D geometry and multiscale features and can incorporate a wide range of matrix materials, such as polymers, metals, and ceramics, to fabricate nanocomposites for new device structures and applications.

9.
Environ Sci Pollut Res Int ; 30(17): 49577-49590, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36781672

RESUMO

The "trinitrogen" [ammonia nitrogen (NH4+ - N), nitrate nitrogen (NO3- - N), and nitrite nitrogen (NO2- - N)] from industrial or domestic wastewater can lead to eutrophication of water bodies. When ammonia nitrogen is converted into nitrate nitrogen, it will cause high nitrogen oxygen demand, which will also lead to hyperammonemia. High nitrite content in water bodies will increase the risk of human cancer. In this paper, Fe-Ce bimetallic-doped composites (Fe-Ce/SiO2 and Fe-Ce-SiO2/TiO2) were synthesized using SiO2 aerogel as a carrier for the adsorption and degradation of "three nitrogen."SiO2/TiO2 was prepared by dipping method, and Fe and Ce bimetals were loaded on the surface of SiO2/TiO2 material, and the effect of photo-Fenton oxidation on the degradation rate of three nitrogen under different materials was explored. The results showed that when the dosage of catalyst was 0.01 g, pH value was 11.0, and the concentration of H2O2 was 80 mmol/L, the photocatalytic efficiency was the best, and the degradation efficiency of three nitrogen remained above 70%.


Assuntos
Nitratos , Nitritos , Humanos , Nitritos/química , Nitratos/química , Amônia/química , Dióxido de Silício/química , Peróxido de Hidrogênio/química , Titânio/química , Água , Nitrogênio , Catálise
10.
Environ Sci Pollut Res Int ; 30(1): 917-929, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35908032

RESUMO

The presence of methoxychlor (MXC) in soil and wastewater is considered a nonnegligible environmental threat. Herein, Fe3O4@Fe(0) was obtained by NaBH4 reduction of Fe3O4 nanoparticles and served as a carrier for laccase to construct catalyst. The catalyst was evaluated for the degradation of MXC in treated wastewater and soil with 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) being used as cocatalyst. The removal rate of MXC in wastewater and soil was found to be 89% and 88% in optimum conditions, and the influences of initial MXC concentration, pH, and temperature on the degradation rate were evaluated. The metabolites including 2-methylpentane, 3-methylpentane, and n-pentane of MXC were identified, and possible degradation mechanisms were proposed. Overall, this work successfully demonstrates not only the ability to degrade MXC in different circumstances but also provides a new idea for environmental remediation in the future.


Assuntos
Enzimas Imobilizadas , Metoxicloro , Águas Residuárias , Catálise , Solo
11.
Nanotechnology ; 34(10)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36542353

RESUMO

Ellipsoidal-Fe3O4@SiO2@mSiO2-C18@dopamine hydrochloride-graphene quantum dots-folic acid (ellipsoidal-HMNPs@PDA-GQDs-FA), a dual-functional drug carrier, was stepwise constructed. Theα-Fe2O3ellipsoidal nanoparticles were prepared by a hydrothermal method, and then coated with SiO2by Stöber method. The resulting core-shell structure, Fe3O4@SiO2@mSiO2-C18magnetic nano hollow spheres, abbreviated as HMNPs, was finally grafted with graphene quantum dots (GQDs), dopamine hydrochloride (PDA) and folic acid (FA) by amide reaction to obtain HMNPs@PDA-GQDs-FA. Transmission electron microscopy, Fourier transform infrared spectroscopy, fluorescence spectroscopy and element analysis proved the successful construction of the HMNPs@PDA-GQDs-FA nanoscale carrier-cargo composite. The carrier HMNPs@PDA-GQDs-FA has higher load (51.63 ± 1.53%) and release (38.56 ± 1.95%) capacity for gambogic acid (GA). Cytotoxicity test showed that the cell survival rate was above 95%, suggesting the cytotoxicity of the carrier-cargo was very low. The cell lethality (74.91 ± 1.2%) is greatly improved after loading GA because of the magnetic targeting of HMNPs, the targeting performance of FA to tumor cells, and the pH response to the surrounding environment of tumor cells of PDA. All results showed that HMNPs@PDA-GQDs-FA had good biocompatibility and could be used in the treatment of VX2 tumor cells after loading GA.


Assuntos
Grafite , Pontos Quânticos , Pontos Quânticos/química , Grafite/farmacologia , Grafite/química , Ácido Fólico , Dióxido de Silício , Dopamina
12.
Schizophrenia (Heidelb) ; 8(1): 11, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232977

RESUMO

Schizophrenia is a complex polygenic disease that is affected by genetic, developmental, and environmental factors. Accumulating evidence indicates that environmental factors such as maternal infection and excessive prenatal neuroinflammation may contribute to the onset of schizophrenia by affecting epigenetic modification. We recently identified a schizophrenia-associated upregulated long noncoding RNA (lncRNA) RP5-998N21.4 by transcriptomic analysis of monozygotic twins discordant for schizophrenia. Importantly, we found that genes coexpressed with RP5-998N21.4 were enriched in immune defense-related biological processes in twin subjects and in RP5-998N21.4-overexpressing (OE) SK-N-SH cell lines. We then identified two genes encoding an interferon-induced protein with tetratricopeptide repeat (IFIT) 2 and 3, which play an important role in immune defense, as potential targets of RP5-998N21.4 by integrative analysis of RP5-998N21.4OE-induced differentially expressed genes (DEGs) in SK-N-SH cells and RP5-998N21.4-coexpressed schizophrenia-associated DEGs from twin subjects. We further demonstrated that RP5-998N21.4 positively regulates the transcription of IFIT2 and IFIT3 by binding to their promoter regions and affecting their histone modifications. In addition, as a general nuclear coactivator, RMB14 (encoding RNA binding motif protein 14) was identified to facilitate the regulatory role of RP5-998N21.4 in IFIT2 and IFIT3 transcription. Finally, we observed that RP5-998N21.4OE can enhance IFIT2- and IFIT3-mediated immune defense responses through activation of signal transducer and activator of transcription 1 (STAT1) signaling pathway in U251 astrocytoma cells under treatment with the viral mimetic polyinosinic: polycytidylic acid (poly I:C). Taken together, our findings suggest that lncRNA RP5-998N21.4 is a critical regulator of immune defense, providing etiological and therapeutic implications for schizophrenia.

13.
ACS Omega ; 6(10): 6537-6546, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748565

RESUMO

In situ TEM utilizing specialized holders and MEMS chips allows the investigation of the interaction, evolution, property, and function of nanostructures and devices responding to designed environments and/or stimuli. This mini-review summarizes the recent progress of in situ TEM with a liquid cell and a flow channel for the investigation of interactions among aqueous nanoparticles, electrolytes, and electrodes under the influence of electric bias and electron beam. A focus is made on nanoparticle growth by electrodeposition, particle nucleation induced by electric biasing or electron beam, self-assembly, and electrolyte breakdown. We also outline some future opportunities of in situ TEM with aqueous cells and flow.

14.
Mol Psychiatry ; 26(8): 4511-4528, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32015466

RESUMO

Schizophrenia is a complex genetic disorder, the non-Mendelian features of which are likely complicated by epigenetic factors yet to be elucidated. Here, we performed RNA sequencing of peripheral blood RNA from monozygotic twins discordant for schizophrenia, and identified a schizophrenia-associated upregulated long noncoding RNA (lncRNA, AC006129.1) that participates in the inflammatory response by enhancing SOCS3 and CASP1 expression in schizophrenia patients and further validated this finding in AC006129.1-overexpressing mice showing schizophrenia-related abnormal behaviors. We find that AC006129.1 binds to the promoter region of the transcriptional repressor Capicua (CIC), facilitates the interactions of DNA methyltransferases with the CIC promoter, and promotes DNA methylation-mediated CIC downregulation, thereby ameliorating CIC-induced SOCS3 and CASP1 repression. Derepression of SOCS3 enhances the anti-inflammatory response by inhibiting JAK/STAT-signaling activation. Our findings reveal an epigenetic mechanism with etiological and therapeutic implications for schizophrenia.


Assuntos
Metilação de DNA , RNA Longo não Codificante , Esquizofrenia , Proteína 3 Supressora da Sinalização de Citocinas , Animais , Regulação para Baixo , Humanos , Inflamação , Camundongos , RNA Longo não Codificante/genética , Esquizofrenia/genética , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
15.
ACS Appl Mater Interfaces ; 12(48): 53705-53711, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33201663

RESUMO

In 2D organic-inorganic hybrid perovskite materials, layers of conducting inorganic material are separated by insulating organic spacers whose length and composition can be tuned. We report the heat capacity and cross-plane thermal conductivity of 2D alkylammonium lead iodide single crystals with increasing chain length, (CnH2n+1NH3)2PbI4 (n = 4-7). The measured thermal conductivities are some of the lowest ever recorded for single crystals, with averages in the range k = 0.099-0.125 W/m K. Although a model based on independent interface resistances between adjacent layers predicts an increase in thermal conductivity with a chain length of more than 30%, experimentally we find that the thermal conductivity is nearly independent of chain length and possibly decreases. We hypothesize that phonons carry an appreciable portion of the heat across the interface coherently, rather than being limited by individual weak interfaces.

16.
Nanoscale ; 12(33): 17530-17537, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32812597

RESUMO

Recent advances in manipulating plasmonic properties of metal/semiconductor heterostructures have opened up new avenues for basic research and applications. Herein, we present a versatile strategy for the assembly of arrays of plasmonic metal/semiconductor hemispherical nano-heterostructures (MSHNs) with control over spacing and size of the metal/semiconductor heterostructure array, which can facilitate a wide range of scientific studies and applications. The strategy combines nanosphere lithography for generating the metal core array with solution-based chemical methods for the semiconductor shell that are widely available and kinetically controllable. Periodic arrays of Au/Cu2O and Ag/Cu2O heterostructures are synthesized to demonstrate the approach and highlight the versatility and importance of the tunability of plasmonic properties. The morphology, structure, optical properties, and elemental compositions of the heterostructures were analyzed. This strategy can be important for understanding and manipulating fundamental nanoscale solid-state physical and chemical properties, as well as assembling heterostructures with desirable structure and functionality for applications.

17.
Nanotechnology ; 31(35): 355704, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32428890

RESUMO

Atomic-scale catalysts leverage the advantages of both heterogeneous catalysts for their stability and reusability and homogeneous catalysts for their isolated active sites. Here, a palladium catalyst supported by Si-thiol, a commercially available mercaptopropyl-modified and TMS-passivated amorphous silica, was synthesized and characterized by SEM,TEM, aberration-corrected STEM-HAADF, XRD, FT-IR and XPS. Statistical analysis revealed that the catalytic Pd species predominantly consisted of intermediate sized nanoparticles (<2 nm), small amounts of essentially isolated atoms (ca. 0.1 nm), and limited amounts of somewhat larger nanoparticles (<5 nm). The nanoscale atomic clusters dominated the reactivity and served as the key active sites for Suzuki coupling. The outcomes of the reaction were greatly affected by the choice of solvents, and Pd/Si-thiol was demonstrated to be reusable for more than three times without a noticeable loss of catalytic activity. [Formula: see text].

18.
J Hazard Mater ; 386: 121977, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911381

RESUMO

Removal of hazardous NO at low temperature via photo-assisted selective catalytic reduction (photo-SCR) strategy is promising, however fully harvesting of solar energy and achieving high SO2/H2O tolerance still remain a challenge. Herein, the phosphoric acid modified natural attapulgite(P-ATP) was employed as a matrix to immobilize CeVO4 by microwave hydrothermal method. Results show that P-ATP provides abundant active sites facilitating the in situ grow of CeVO4 nanorods on its surface which hierarchically construct a dendritic-like photocatalyst. The near-infrared (NIR) light is upconverted to visible and UV light through CeVO4 which not only broaden the absorption range of solar light, but also build Z-scheme heterostructure with P-ATP enhancing the redox potential of charge carriers. The CeVO4/P-ATP nanocomposite can reach as high as 92 % for NO conversion under full-spectrum solar irradiation, while retaining nearly 60 % conversion under NIR light. Moreover, the catalyst exhibits outstanding tolerance with SO2 and H2O due to the presence of Ce species which can prevent NH3 from being sulfated, while ATP prevent catalyst from being corroded by H2O. This work may open up a new window for full-spectrum driven SCR of NO based on cost-effective mineral catalyst.

19.
J Nanosci Nanotechnol ; 20(4): 2104-2113, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492218

RESUMO

In this work, stable superparamagnetic core-shell Fe2B@SiO2 nanoparticles were prepared by "one pot" chemical reduction of ferric ion salts with NaBH4 and silica shell coating in the presence of citric acid stabilizer. The X-ray (XRD) and selection of electron diffraction (SAED) revealed that Fe2B@SiO2 nanoparticles were chiefly composed of silica shell and Fe2B with a small amount of α-Fe. Then, graphene oxide (GO) was assembled onto core-shell Fe2B@SiO2 nanoparticles for Epirubicin (EPI) loading and releasing, and the adsorption isotherm of EPI on Fe2B@SiO2@GO was analyzed. The results showed, the adsorption process includes two steps, due to the π-π stacking effect of EPI on the Fe2B@SiO2@GO. The EPI loading efficiency of the magnetic nanoparticles was as high as 90%, while the EPI-loaded core-shell Fe2B@SiO2 nanoparticles showed an obvious pH controlled drug release behavior, and showed lower cumulative release rate when pH is 7.4 than that when pH is 5.7. The prepared nanoparticles demonstrated potential application in killing tumor cells while minimizing the toxicity to normal tissues.


Assuntos
Grafite , Nanopartículas , Epirubicina , Dióxido de Silício
20.
Materials (Basel) ; 12(21)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731493

RESUMO

In this study, the influence of rotary-die equal channel angular pressing (RD-ECAP) processing on the mechanical properties and rolling formability of AZ91 alloys was investigated. The as-cast and pre-homogenized AZ91 alloys were pre-processed by RD-ECAP for 16 passes at 573 K and subjected to post-ECAP rolling at 573 K with a rolling speed of 10 m/min. The microstructure and deformation characteristics of the AZ91 alloys were characterized. Results demonstrated that fine-grained AZ91 alloys with improved strength and ductility were obtained via the high-pass RD-ECAP processing, indicating a good plastic formability. The ECAP-ed alloys were easily rolled at 573 K from 4.5 mm to 1.1 mm in thickness without edge cracking. After rolling, heterogeneous grain structures were observed with large numbers of twins and shear bands that created strong basal textures. The rolled AZ91 alloys exhibited higher tensile strength and appropriate elongation. The post-ECAP rolling was successfully used in the high productivity of AZ91 rolled plates with good mechanical properties.

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