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1.
iScience ; 27(4): 109447, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38523790

RESUMO

Maternal hyperhomocysteinemia is widely considered as an independent risk of congenital heart disease (CHD). However, whether high paternal homocysteine causes CHD remains unknown. Here, we showed that increased homocysteine levels of male mice caused decreased sperm count, sperm motility defect and ventricular septal defect of the offspring. Moreover, high levels of paternal homocysteine decrease sperm DNMT3A/3B, accompanied with changes in DNA methylation levels in the promoter regions of CHD-related genes. Folic acid supplement could decrease the occurrence of VSD in high homocysteine male mice. This study reveals that increased paternal homocysteine level increases VSD risk in the offspring, indicating that decreasing paternal homocysteine may be an intervening target of CHD.

2.
EMBO Mol Med ; 15(12): e17745, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37840432

RESUMO

Prenatal diagnosis of congenital heart disease (CHD) relies primarily on fetal echocardiography conducted at mid-gestational age-the sensitivity of which varies among centers and practitioners. An objective method for early diagnosis is needed. Here, we conducted a case-control study recruiting 103 pregnant women with healthy offspring and 104 cases with CHD offspring, including VSD (42/104), ASD (20/104), and other CHD phenotypes. Plasma was collected during the first trimester and proteomic analysis was performed. Principal component analysis revealed considerable differences between the controls and the CHDs. Among the significantly altered proteins, 25 upregulated proteins in CHDs were enriched in amino acid metabolism, extracellular matrix receptor, and actin skeleton regulation, whereas 49 downregulated proteins were enriched in carbohydrate metabolism, cardiac muscle contraction, and cardiomyopathy. The machine learning model reached an area under the curve of 0.964 and was highly accurate in recognizing CHDs. This study provides a highly valuable proteomics resource to better recognize the cause of CHD and has developed a reliable objective method for the early recognition of CHD, facilitating early intervention and better prognosis.


Assuntos
Cardiopatias Congênitas , Proteoma , Gravidez , Humanos , Feminino , Estudos de Casos e Controles , Proteômica , Cardiopatias Congênitas/diagnóstico , Biomarcadores , Cisplatino , Ciclofosfamida
3.
Phys Chem Chem Phys ; 25(29): 19492-19500, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37448277

RESUMO

This work reports the refinement of nanoporous copper (NPC) ligaments by introducing the sodium dodecyl sulfate (SDS) surfactant in the dealloying process. The Al80Cu20 (at%) alloy precursor is chemically dealloyed in a mixed solution of NaOH and SDS surfactant, producing NPC with a hierarchical microstructure. Micron-scaled skeletons that build up higher level networks consist of geometrically similar nano-scaled bi-continuous ligament-pore networks at the lower level. It has been found that the size of the ligaments in the lower level networks reduces from ∼32 nm to ∼24 nm with increasing SDS concentration to 1 mM. Further increasing the SDS concentration to 5 mM only leads to a slight ligament size decrease to ∼21 nm. Remarkably, nano-sized cones are formed on the lower level network surface in the dealloying solution containing 1 mM SDS, and the cone number greatly rises when the SDS concentration increases to 5 mM. The surface diffusivity of Cu adatoms is evaluated based on the experimental data, and the refinement of the ligament as well as the formation of cones are associated with the decreased surface diffusivity and the retarded Cu adatom motions with the addition of SDS. Quantum chemical calculations and molecular dynamics simulations are performed to model the adsorption behavior of SDS. It has been found that the SDS-substrate interaction increases with the number of SDS molecules before SDS reaches saturation.

4.
J Colloid Interface Sci ; 648: 12-24, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295364

RESUMO

Recently, molybdenum disulfide (MoS2)/carbon has become a promising candidate for efficient microwave absorption. However, it is still challenging to simultaneously optimize the synergy of impedance matching and loss capability at the level of a thin absorber. Here, a new adjustment strategy is proposed by changing the concentration of precursor l-cysteine for MoS2/multi-walled carbon nanotubes (MWCNT) composites to unlock the basal plane of MoS2 and expand the interlayer spacing from 0.62 nm to 0.99 nm, leading to improved packing of MoS2 nanosheets and more active sites. Therefore, the tailored MoS2 nanosheets exhibit abundant sulfur-vacancies, lattice-oxygen, more metallic 1T-phase, and higher surface area. Such sulfur-vacancies and lattice-oxygen promote the electronic asymmetric distribution at the solid-air interface of MoS2 crystals and induce stronger microwave attenuation through interface/dipole polarization, which is further verified by first-principles calculations. In addition, the expansion of the interlayer spacing induces more MoS2 to deposit on the MWCNT surface and increases the roughness, improving the impedance matching and multiple scattering. Overall, the advantage of this adjustment method is that while optimizing impedance matching at the thin absorber level, composite still maintains a high attenuation capacity, which means enhancing the attenuation performance of MoS2 itself offsets the weakening of the composite's attenuation ability caused by the decrease in the relative content of MWCNT components. Most importantly, adjusting impedance matching and attenuation ability can be easily implemented by separate control of l-cysteine content. As a result, the MoS2/MWCNT composites achieve a minimum reflection loss value of -49.38 dB and an effective absorption bandwidth of 4.64 GHz at a thickness of only 1.7 mm. This work provides a new vision for the fabrication of thin MoS2-carbon absorbers.

5.
Foods ; 13(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38201156

RESUMO

The prevalence of norovirus in oysters poses a significant threat to food safety, necessitating a comprehensive understanding of contamination patterns. This study explores the temporal dynamics of norovirus distribution in various oyster tissues over a contamination period ranging from 6 to 96 h. Four tissues-the gill, palp, digestive gland, and stomach-were subjected to systematic monitoring using RT-qPCR for absolute quantification. Results revealed rapid norovirus detection in all tissues six hours post-contamination, with subsequent variations in detection rates. Gill and digestive gland tissues exhibited a peak in detection at 12-24 h, aligning with the oyster's gastrointestinal circulatory system. The digestive gland, distinguished by specific enrichment and adsorption capabilities, demonstrated the highest virus concentration at 48 h. In contrast, the stomach displayed a reemergence of norovirus. Beyond 72 h, detection remained exclusive to the digestive gland, with Ct values comparable to earlier time points. At 96 h, a limited amount of norovirus was detected in the digestive gland, emphasizing the importance for timely monitoring. In addition to providing critical insights into optimal detection strategies, these findings highlight the time-related characteristics of norovirus contamination in oysters. The study identifies the digestive gland as a key target for reliable monitoring, providing valuable data to improve protocols for reducing hazards associated with oyster consumption and foodborne norovirus infections. This research contributes to the understanding of norovirus dynamics in oyster tissues and reinforces current efforts aimed at ensuring food safety and public health.

6.
Sensors (Basel) ; 22(3)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35161981

RESUMO

The method of making precise measurements of remote water depth using mmWave technology has great potential for preventing urban waterlogging. To achieve waterlogging prevention, the mmWave system needs to measure the water depth change accurately with a short acquisition time. This paper demonstrates a new accurate mmWave water depth measurement system based on Frequency Modulated Continuous Wave (FMCW) Radar with a center frequency of 77 GHz. To improve distance resolution and lower acquisition time, the Swept Frequency-Cross Correlation (SFCC) algorithm is proposed for the first time to improve the distance computation resolution by 9× and lower time complexity from O(n·logn) to O(n) compared to traditional FFT-based FMCW radar distance computation. A prototype system equipped with a humidity sensor, a processor module and TI's FMCW radar module is designed for monitoring urban floods in cities. Using the prototype system with the proposed SFCC, the depth measurement error is reduced from 4.5 cm to less than 5 mm, compared to the default radar post-processing algorithm embedded in the radar module.

7.
J Colloid Interface Sci ; 609: 33-42, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34894554

RESUMO

Three-dimensional (3D) porous molybdenum disulfide nanosheets/carbon nanofibers (MoS2/CNF) hybrid aerogels were synthesized by using solvothermal method and following carbonization, where two-dimensional (2D) MoS2 nanosheets were homogenously in-situ grown on the interconnected CNF skeleton derived from bacterial cellulose, forming a hierarchical porous structure. This unique heterogeneous structure of the MoS2/CNF hybrid aerogels were conducive to electromagnetic loss, including conduction, polarization, multi-scatterings, and reflections, thus resulting in a balanced impedance matching and microwave attenuation capacity. It was found that the resulted MoS2/CNF hybrid aerogels demonstrate excellent microwave absorbing performance when the only 5.0 wt% fillers were loaded in paraffin. Particularly, MoS2/CNF-2-900 hybrid aerogel displayed an effective absorption bandwidth of 5.68 GHz and minimum reflection loss (RLmin) value of -36.19 dB at a thickness of 2.0 mm. As the thickness increases to 4.4 mm, the RLmin value of MoS2/CNF-2-900 hybrid aerogel reaches -48.53 dB. Electromagnetic loss mechanism analysis indicates that such improved microwave attenuation is attributed to proper component, multiple heterogenous interface and hierarchical porous structures. All the results in this work pave the avenue for the development of ultralight microwave absorber with high absorption capacity as well as broad effective absorption bandwidth.


Assuntos
Nanofibras , Carbono , Celulose , Micro-Ondas , Molibdênio
8.
Cell Rep ; 37(2): 109821, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34644569

RESUMO

Elevation in homocysteine (Hcy) level is associated with insulin resistance; however, the causality between them and the underlying mechanism remain elusive. Here, we show that Hcy induces insulin resistance and causes diabetic phenotypes by protein cysteine-homocysteinylation (C-Hcy) of the pro-insulin receptor (pro-IR). Mechanistically, Hcy reacts and modifies cysteine-825 of pro-IR in the endoplasmic reticulum (ER) and abrogates the formation of the original disulfide bond. C-Hcy impairs the interaction between pro-IR and the Furin protease in the Golgi apparatus, thereby hindering the cleavage of pro-IR. In mice, an increase in Hcy level decreases the mature IR level in various tissues, thereby inducing insulin resistance and the type 2 diabetes phenotype. Furthermore, inhibition of C-Hcy in vivo and in vitro by overexpressing protein disulfide isomerase rescues the Hcy-induced phenotypes. In conclusion, C-Hcy in the ER can serve as a potential pharmacological target for developing drugs to prevent insulin resistance and increase insulin sensitivity.


Assuntos
Antígenos CD/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Homocisteína/metabolismo , Hiper-Homocisteinemia/metabolismo , Resistência à Insulina , Processamento de Proteína Pós-Traducional , Receptor de Insulina/metabolismo , Tecido Adiposo/metabolismo , Animais , Células CHO , Cricetulus , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Modelos Animais de Doenças , Furina/genética , Furina/metabolismo , Células HEK293 , Células Hep G2 , Homocisteína/sangue , Humanos , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/genética , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Ratos
9.
Phys Rev E ; 103(2-1): 022313, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33735975

RESUMO

The robustness of complex networks against attack has been an important issue for decades. Most of the previous studies focused on targeted attack (TA) and random attack (RA), while recently localized attack (LA) has drawn the attention of researchers. However, the existing studies related to LA mainly aim to reveal the properties on various network topologies so that the strategy to enhance network robustness against LA is still not well studied. In this paper, we propose a global disassortative rewiring strategy to enhance the robustness of scale-free networks against LA without changing the degree distribution. The validations are conducted on simulated scale-free networks and two real-life networks. As global disassortative rewiring strategy outperforms the other strategies, it can be proved effective in enhancing network robustness against LA and may contribute to future network risk reduction. In addition, by avoiding calculating and comparing the localized-robustness measurement within each rewire operation, our strategy offers a significant advantage in computational efficiency.

10.
Virol Sin ; 35(1): 103-109, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31777010

RESUMO

Rotavirus (RV) is a major foodborne pathogen. For RV prevention and control, it is a key to uncover the interaction mechanism between virus and its receptors. However, it is hard to specially purify the viral receptors, including histo-blood group antigens (HBGAs). Previously, the protruding domain protein (P protein) of human norovirus (genotype II.4) was displayed on the surface of Escherichia coli, and it specifically recognized and captured the viral ligands. In order to further verify the feasibility of the system, P protein was replaced by VP8* of RV (G9P[8]) in this study. In the system, VP8* could be correctly released by thrombin treatment with antigenicity retaining, which was confirmed by Western blot and Enzyme-Linked Immunosorbent Assays. Type A HBGAs from porcine gastric mucin (PGM) were recognized and captured by this system. From saliva mixture, the captured viral receptor bound with displayed VP8* was confirmed positive with monoclonal antibody against type A HBGAs. It indicated that the target ligands could be easily separated from the complex matrix. These results demonstrate that the bacterial surface display system will be an effective platform to explore viral receptors/ligands from cell lines or food matrix.


Assuntos
Técnicas de Visualização da Superfície Celular/métodos , Receptores Virais/genética , Rotavirus/genética , Animais , Escherichia coli , Genótipo , Humanos , Ligação Proteica , Proteínas de Ligação a RNA/genética , Infecções por Rotavirus/virologia , Saliva/virologia , Suínos , Proteínas não Estruturais Virais/genética
11.
Phys Chem Chem Phys ; 18(31): 21562-72, 2016 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-27425769

RESUMO

With the extensive study of dealloying, copper oxides have been shown to be important members and exhibit huge potential in catalysis, energy transformation and storage fields. In this work, nanostructured copper/copper oxide hybrids were prepared through dealloying the sintered Al85Cu15 alloy and molecular dynamics (MD) simulations as well as calculations based on density functional theory (DFT) were performed to explore the oxidation mechanisms of copper in aqueous electrolytes. Cu/Cu2O/CuO compositions were obtained after immersing the sintered alloys in 20 wt% NaOH solutions under corrosion-free conditions at room temperature. Both X-ray diffraction (XRD) and potentiodynamic polarization results reveal that there exist large differences between the sintered Al85Cu15 alloy and its counterpart cast alloy and the Rietveld simulation analysis as well as MD simulations testify to the inhomogeneous atom distribution in the sintered alloy. DFT studies show that Cun (1 ≤n≤ 9) clusters possess higher surface energies than the Cu(111) surface and the calculated binding energies of the copper clusters and an atomic oxygen (Cun-O) are much higher than that of Cu(111)-O. The low surface diffusivity (Ds) of the clusters at the alloy-electrolyte interface extends their diffusion time, which may be beneficial to the formation and growth of oxide nuclei precursors during the dealloying process. Their microstructures and morphologies characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that CuO exists in the form of a nanoplate while Cu2O is a nanoparticle. Nanoporous copper (NPC) obtained by dealloying sintered and cast alloys exists in the form of a bicontinuous ligament-channel structure. This work enriches the dealloying research from both experimental and theoretical aspects.

12.
J Nanosci Nanotechnol ; 15(4): 3076-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26353538

RESUMO

In this study, nano-sized WO3 powder was dispersed into Co4Sb1.7Te0.3 thermoelectric matrix by ball milling and hot-press sintering technology. The results of scanning electron microscopy (SEM) showed that the WO3 phase distributed uniformly in the form of inclusions on the matrix. High-resolution transmission electron microscopy (HRTEM) presented that the average size of embedded nano-WO3 was about 50 nm. With the content of WO3 increasing, the electrical conductivity (σ) of Co4Sb11.7Te0.3 decreased and the absolute value of Seebeck coefficient (a) increased. The absolute value of a for 1.5% WO3/Co4Sb11.7Te0.3 composite was 258 µV/K at 650 K. The minimal lattice thermal conductivity (K(L)) of WO3/Co4Sb11.7Te0.3 achieved in the present work was 1.52 W/m K at 650 K. The total thermal conductivity (K) of WO3/Co4Sb11.7Te0.3 composites decreased obviously, which resulted from the phonon scattering by the WO3 inclusions locating on the grain boundaries of Co4Sb11.7Te0.3 matrix. The highest ZTof 0.71 was achieved at 750 K for 1.5%WO3/Co4Sb11.7Te0.3 composite.

13.
J Nanosci Nanotechnol ; 14(9): 6894-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924346

RESUMO

A series of modified Ni-Zn bimetallic catalysts were prepared by depositing different kinds of 4 wt% metals (Ir, Pt, Au, Cu, Ag) on the Ni-Zn-Al hydrotalcite (NZAH) and tested in the selective hydrogenation of acetylene. The activity was enhanced by 3-fold over the 4 wt% Au/NZAH, meanwhile, the yield of C2H4 was also increased more than 4 times compared with the NZAH. Characterization by means of H2-TPR, XRD, SEM, and TEM revealed that Au was highly dispersed on the catalyst, and the ternary Au-Ni-Zn alloy was formed during the H2 reduction at 500 degrees C. Doping Au in Ni-Zn bimetallic catalyst weakens the adsorption of acetylene and also hinders the coke deposition on the catalyst, which leads to the enhanced activity in acetylene hydrogenation.

14.
Chem Asian J ; 8(11): 2721-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23868702

RESUMO

A nanoporous (NP) PdCo alloy with uniform structure size and controllable bimetallic ratio was fabricated simply by one-step mild dealloying of a PdCoAl precursor alloy. The as-made alloy consists of a nanoscaled bicontinuous network skeleton with interconnected hollow channels that extend in all three dimensions. With a narrow ligament size distribution around 5 nm, the NP PdCo alloy exhibits much higher electrocatalytic activity towards the oxygen-reduction reaction (ORR) with enhanced specific and mass activities relative to NP Pd and commercial Pt/C catalysts. A long-term stability test demonstrated that NP PdCo has comparable catalytic durability with less loss of ORR activity and electrochemical surface area than Pt/C. The NP PdCo alloy also shows dramatically enhanced catalytic activity towards formic acid electrooxidation relative to NP Pd and Pd/C catalysts. The as-made NP PdCo holds great application potential as a promising cathode as well as an anode electrocatalyst in fuel cells with the advantages of superior catalytic performance and easy preparation.

15.
Langmuir ; 28(3): 1886-92, 2012 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-22195753

RESUMO

The hierarchical nanoporous (NP) PtFe alloy with multimodal size distributions is straightforwardly fabricated by means of mild de-alloying of the PtFeAl source alloy. This interesting NP structure consists of interconnected larger ligaments around hundreds of nanometers, in which these ligaments are also composed of the three-dimensional network structure with the typical size at 3 nm. In comparison to NP-Pt and Pt/C catalysts, the as-made alloy nanostructure exhibits superior electrocatalytic activity for the methanol oxidation reaction (MOR) with higher catalytic durability and CO tolerance besides the enhanced specific and mass activity. NP-PtFe also shows improved structure stability with the less loss of the electrochemical surface area of Pt upon long-term potential scan in acidic solution. X-ray photoelectron spectroscopy and density functional theory calculations demonstrate that the incorporation of Fe appropriately modified the electron structure of Pt with the downshift of the Pt d-band center, leading to a decreased CO poisoning and an improved MOR activity.

16.
ACS Appl Mater Interfaces ; 3(12): 4626-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22034948

RESUMO

We describe a general strategy to fabricate a new type of nanoporous core/shell structured bimetallic nanocomposites with controllable metal components. Nanoporous copper (NPC) obtained by dealloying Cu/Al alloy is used as both reducing agent and three-dimensional substrate. Electron microscope and X-ray diffraction characterizations demonstrated that a simply galvanic-replacement reaction with H(2)PtCl(6) aqueous solution can easily generate nanoporous core/shell structure with a thin Pt/Cu alloy shell and Cu (or Pt/Cu alloy) core. The morphology and crystal structure evolution of the nanocomposites are studied and discussed in detail. The as-prepared bimetallic PtCu nanocomposites show greatly enhanced catalytic activity and stability toward methanol electro-oxidation as compared with commercial Pt/C catalyst. This facile in situ preparation strategy is also suitable for large-scale production of this novel and inexpensive catalyst.


Assuntos
Eletroquímica/instrumentação , Nanocompostos/química , Catálise , Cobre/química , Paládio/química , Compostos de Platina/química , Porosidade
17.
Anal Chim Acta ; 703(2): 172-8, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21889631

RESUMO

Nanoporous copper (NPC) obtained by dealloying CuAl alloy is used as both three-dimensional template and reducing agent for the fabrication of nanoporous PdCu alloy with hollow ligaments by a simple galvanic replacement reaction with H(2)PdCl(4) aqueous solution. Electron microscopy and X-ray diffraction characterizations demonstrate that after the replacement reaction, the ligaments become hollow tubular structure and the ligament shell is also comprised of small pores and nanoparticles with a typical size of ~4 nm (third order porosity). The as-prepared nanotubular mesoporous PdCu alloy (NM-PdCu) structure exhibits remarkably improved electrocatalytic activity towards the oxidation of formic acid and H(2)O(2) compared with nanoporous Pd (NP-Pd), and can be used for sensitive electrochemical sensing applications. After coupled with glucose oxidase (GOx), the enzyme modified NM-PdCu electrode can sensitively detect glucose over a wide linear range (0.5-20 mM).


Assuntos
Ligas/química , Técnicas Biossensoriais/métodos , Nanoestruturas/química , Catálise , Cobre/química , Técnicas Eletroquímicas , Eletrodos , Formiatos/química , Glucose/análise , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/química , Chumbo/química , Nanoestruturas/ultraestrutura , Oxirredução , Porosidade
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