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1.
Phys Chem Chem Phys ; 22(8): 4626-4631, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32051988

RESUMO

Based on the newly developed SCAN meta-GGA and the widely used PBE-GGA functionals, ab initio molecular dynamics are performed on water. It is proved that, although the SCAN meta-GGA is not as good as the TIP4P/2005 model potential in describing the equation of state of water, it is much better than the PBE-GGA, the ST2 model potential, and ab initio trained neural network potentials. Moreover, the SCAN meta-GGA predicts a first-order liquid-liquid transition from high- to low-density water at negative pressure, in which the structures are qualitatively consistent with experimental observations, and the spinodal point of high-density water is very close to Speedy's stability limit line.

3.
J Oncol ; 2022: 2832920, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342419

RESUMO

This study aims to reveal the potential effect of circNBPF10 on the malignant progression of lung cancer. The expression levels of circNBPF10 in lung cancer tissues and cell lines were detected via real-time quantitative PCR (RT-qPCR). The relationship between circNBPF10 expression and lung cancer metastasis was further analyzed. Effects on lung cancer cells after the knockout or overexpression of circNBPF10 were detected. Subsequently, the regulatory relationship of circNBPF10 with miR-224 was detected by using the dual-luciferase reporter gene. In addition, the role of pre-B-cell homeo box 3 (PBX3) in the progression of lung cancer affected by circNBPF10 was evaluated through a rescue experiment. circNBPF10 was highly expressed in lung cancer tissues and lung cancer cell lines. The expression level of circNBPF10 was significantly higher in patients with lung cancer and lymphatic metastasis or distant metastasis than in patients with nonmetastatic lung cancer. The downregulation of circNBPF10 reduced the proliferation, migration, and invasion of lung cancer cells. In lung cancer cells, circNBPF10 negatively regulated the expression of miR-224, whereas miR-224 directly targeted the expression of PBX3. The results of the rescue experiment confirmed that PBX3 was the key gene for the promoting effect of circNBPF10 on the malignant progression of lung cancer. circNBPF10 was highly expressed in lung cancer tissues and was associated with distant metastasis and poor prognosis in patients with lung cancer. circNBPF10 upregulated PBX3 by targeting miR-224 and promoted the malignant progression of lung cancer.

4.
Front Microbiol ; 12: 771170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975798

RESUMO

Treatment strategies of infection by carbapenem-resistant Klebsiella pneumoniae (CRKP) are limited. Fosfomycin, a broad-spectrum antibiotic, has attracted renewed interest in combination therapy to fight K. pneumoniae infections. However, reports on fosfomycin-resistant K. pneumoniae are increasing. Among the 57 CRKP strains, 40 (70.2%) were resistant to fosfomycin. Thus, whole-genome sequencing and bioinformatics analysis were conducted to reveal molecular characteristics of fosfomycin-resistant K. pneumoniae. Twenty-three isolates coharbored fosA kp and fosA3, with K. pneumoniae carbapenemase (KPC)-producing ST11-KL64-wzi64-O2 (n = 13) and ST11-KL47-wzi209-OL101 (n = 8), the predominating clonal groups, while fosA3 was not detected in isolates carrying class B carbapenemase genes. Twenty-two (out of 26) ST11-KL64 strains were positive for rmpA2, of which 12 carried fosA3. Four of the 23 fosA3-positive isolates could successfully transfer their fosfomycin-resistant determinants to Escherichia coli J53Azi R . All four strains belonged to ST11-KL47 with the same pulsed-field gel electrophoresis profile, and their transconjugants acquired fosfomycin, carbapenem, and aminoglycoside resistance. A 127-kb conjugative pCT-KPC-like hybrid plasmid (pJNKPN52_KPC_fosA) coharboring fosA3, bla KPC-2, bla CTX-M-65, bla SHV-12, rmtB, and bla TEM-1 was identified. ST11-KL64 and ST11-KL47 K. pneumoniae, with higher resistance and virulence, should be critically monitored to prevent the future dissemination of resistance.

5.
RSC Adv ; 8(49): 28198-28208, 2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35548169

RESUMO

The phase assembly and microstructure of the aluminum-incorporated CaO-SiO2-H2O system, which is technologically important in autoclaved building materials, catalysis and waste management, were investigated using XRD, SEM, FTIR and NMR depending on aluminum addition, reaction temperature and curing time. The content of each phase was obtained using the MAUD program based on the Rietveld refinement. The results revealed that the formation of the tobermorite phase was promoted at Al/(Al + Si) ≤ 0.03, and subsequently retarded by higher aluminum addition, which was corroborated by the presence of more low polymerized and cross-linked (alumino)silicate chains. The phase purity decreased with increasing aluminum addition. Aluminum changed the morphology of tobermorite from plate-like to lath-like and fibrous. About a quarter of the (alumino)silicate chains in the C-S-H structure were linked though a [triple bond, length as m-dash]Si-O-Al[triple bond, length as m-dash] configuration, and this proportion was almost independent of aluminum addition. Furthermore, only Al[4] substituted for silicon in the aluminum incorporated C-S-H, while Al[6] just exited in the hydrogarnet phase. This work is beneficial for understanding the implication on micro-properties of by-products or admixtures containing aluminum in concrete.

6.
Biointerphases ; 13(6): 06E407, 2018 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-30408965

RESUMO

Traditional strategies for the functionalization of materials displaying hydroxyl groups either require active esterification reagents or involve the nucleophilic attack of the hydroxyl group toward electrophilic groups. The former tends to hydrolyze in aqueous solutions while the latter occurs under harsh conditions. Herein, the authors reported a new method for the functionalization of hydroxyl groups on the surface via catalytic oxa-Michael addition with vinyl sulfones. Using hydroxyl group terminated self-assembled monolayers as a model surface, a series of organocatalysts were screened and triphenylphosphine stood out for the best catalytic activity. The catalytic reaction on the surface was characterized by x-ray photoelectron spectroscopy. The information of reaction kinetics was obtained using static water contact angle measurements. Once conjugated with ligands onto the functionalized surfaces, the multivalence binding of proteins was investigated by quartz crystal microbalance experiments. By varying the reaction conditions, e.g., catalyst types and reaction times, ligands can be anchored with a controllable density, which would be helpful to establish the relationships between ligand density and bioactivity.


Assuntos
Química Orgânica/métodos , Hidróxidos/metabolismo , Compostos Organofosforados/metabolismo , Sulfonas/metabolismo , Propriedades de Superfície , Cinética , Espectroscopia Fotoeletrônica , Ligação Proteica , Proteínas/metabolismo , Técnicas de Microbalança de Cristal de Quartzo
7.
J Hazard Mater ; 199-200: 448-52, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22088502

RESUMO

High-efficiency recovery and utilization of steel slag are important concerns for environmental protection and sustainable development. To establish a rapid method to evaluate the cementitious properties of steel slag, leaching tests were carried out on steel slag components via an evaporation-condensation method; the leaching characteristics and mechanism of the slag were also investigated. The relationship between leaching characteristics and cementitious properties, which were represented by mortar compressive strength, was analyzed. Results show that there exist significant differences among the amounts of chemically active leached components. The leaching process can be described by the shrinking unreacted core model controlled by intra-particle diffusion, and is in accordance with Kondo R hydration kinetics equation. The leaching process showed a good linear relationship between the amounts of components leached from steel slag and the mortar compressive strength of cementitious materials prepared from reference cement and steel slag with mass ratios of 50:50 and 70:30. The compressive strengths of mortars subjected to 7, 28, and 90 days of curing can be accurately predicted by the sum of leached (CaO+Al(2)O(3)) obtained after a certain length of leaching time.


Assuntos
Materiais de Construção , Aço , Difusão , Teste de Materiais
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