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1.
Phys Chem Chem Phys ; 18(41): 28576-28584, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27711649

RESUMO

The potential of 23 superhalogen anions of halogen-free structures as high-performance electrolytes of Li-ion batteries is theoretically explored here. According to high-level ab initio results at the CCSD(T) level, eight candidates, obeying the Wade-Mingos rule, should be capable of forming electrolytes, which are better than the currently used commercial products. When comparing different methods, MP2 was found to be in good agreement with CCSD(T) in the calculation of ΔELi+ and ΔEH2O, which are parameters describing the performance of potential electrolytes. Thus, MP2 represents a good choice for such calculations, particularly for large potential electrolyte systems wherein CCSD(T) calculations are actually impractical. The five functionals selected here (ωB97XD, B2GP-PLYP, B2K-PLYP, B2T-PLYP and B3LYP) are also capable of reproducing the variational trends of the relative values of different structures at the CCSD(T) level. However, the actual DFT values of ΔELi+ are usually different from those of CCSD(T) by more than 1 eV. These significant deviations may be a problem when accurate ΔELi+ values are required.

2.
J Chem Phys ; 144(5): 054303, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26851917

RESUMO

A systematic density functional theory study including 17 exchange-correlation functionals was performed on different types of superhalogens with high level coupled-cluster single double including perturbative triple excitations (CCSD(T)) results as the reference. The superhalogens selected here cover the ranges from mononuclear to polynuclear structures and from structures with halogen-atom ligands to those with non-halogen ligands, e.g., [MgX3](-), [Mg2X5](-), and [Mg3X7](-) (X = F, Cl, CN). It is clearly indicated that three double-hybrid functionals B2T-PLYP, B2GP-PLYP, B2K-PLYP as well as the range-separated hybrid functional ωB97X are capable of providing results which approach the accuracy at the CCSD(T) level. The basis set effect is usually moderate and, in most cases, it is enough to utilize the basis set of triple-ξ quality, e.g., Def2-TZVP. In addition, the results of the HF and MP2 method are also acceptable here, especially for polynuclear superhalogens where CCSD(T) is probably unpractical.

3.
Chemphyschem ; 16(17): 3652-9, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26337156

RESUMO

An ab initio study of the superhalogen properties of eighteen binuclear double-bridged [Mg2 (CN)5 ](-1) clusters is reported herein by using various theoretical methods. High-level CCSD(T) results indicate that all the clusters possess strong superhalogen properties owing to their high vertical electron detachment energies (VDEs), which exceed 6.8 eV (highest: 8.15 eV). The outer valence Green's function method provides inaccurate relative VDE values; hence, this method is not suitable for this kind of polynuclear superhalogens. Both the HF and MP2 results are generally consistent with the CCSD(T) level regarding the relative VDE values and-especially interesting-the average values of the HF and MP2 VDEs are extremely close to the CCSD(T) results. The distributions of the extra electrons of the anions are mainly aggregated into the terminal CN units. These distributions are apparently different from those of previously reported triple-bridged isomers and may be the reason for the decreased VDE values of the clusters. In addition, comparisons of the VDEs of binuclear and mononuclear superhalogens as well as studies of the thermodynamic stabilities with respect to the detachment of various CN(-1) ligands are also performed. These results confirm that polynuclear structures with pseudohalogen ligands can be considered as probable new superhalogens with enhanced properties.

4.
Phys Chem Chem Phys ; 17(31): 20338-46, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26194876

RESUMO

The regulation of the electronic properties of organic molecules induced by polynuclear superhalogens is theoretically explored here for sixteen composite structures. It is clearly indicated by the higher vertical electron detachment energy (VDE) that polynuclear superhalogens are more effective in regulating the electronic properties than mononuclear structures. However, this enhanced regulation is not only determined by superhalogens themselves but also related to the distribution of the extra electron of the final composites. The composites, in which the extra electron is mainly aggregated into the superhalogen moiety, will possess higher VDE values, as reported in the case of C1', 7.12 eV at the CCSD(T) level. This is probably due to the fact that, compared with organic molecules, superhalogens possess stronger attraction towards the extra electron and thus should lead to lower energies of the extra electrons and to higher VDE values eventually. Compared with CCSD(T), the Outer Valence Green's Function (OVGF) method fails completely for composite structures containing Cl atoms, while MP2 results are generally consistent in terms of the relative order of VDEs. Actually if the extra electron distribution of the systems could be approximated by the HOMO, the results at the OVGF level will be consistent with the CCSD(T) results. Conversely, the difference in VDEs between OVGF and CCSD(T) is significantly large. Besides superhalogen properties, the structures, relative stabilities and thermodynamic stabilities with respect to various fragmentation channels were also investigated for all the composite structures.

5.
Mol Biotechnol ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112962

RESUMO

Gastric cancer (GC) is a malignant tumor with the highest incidence among all kinds of malignant tumors in China. Long noncoding RNAs (LncRNAs) have been reported to act as microRNA (miRNAs) sponges and thus play key roles in biological processes and pathogenesis. Thus, this study aimed to investigate the functional effects and the regulatory mechanism of lncRNA opa interacting protein 5-antisense 1 (OIP5-AS1) in gastric cancer cells. The expression of OIP5-AS1, miR-140-5p, Ubiquitin protein ligase E3 component n-recognin 5 (UBR5) was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis, migration, and invasion were assessed using Cell-Counting Kit-8 (CCK-8), Flow cytometry, and Transwell assays. UBR5 protein level was detected by Western blot. Binding between miR-140-5p and OIP5-AS1 or UBR5 was predicted by Starbasev2.0 and TargetScan, and verified using Dual-luciferase reporter assays and RNA pull-down assay. A xenograft mice model was used to evaluate the effects of OIP5-AS1 on tumor growth in vivo. OIP5-AS1 was upregulated in GC cancer and cells. OIP5-AS1 knockdown inhibited cell proliferation, migration, invasion, but induced cell apoptosis in GC. In mechanism, OIP5-AS1 might serve as a sponge for miR-140-5p to enhance UBR5 expression. Moreover, overexpression of miR-140-5p or UBR5 partly reversed the effects of OIP5-AS1 depletion on the progression of GC cells. Furthermore, OIP5-AS1 depletion also suppressed tumor growth in vivo. OIP5-AS1 silencing might suppress proliferation, migration, invasion, and induced apoptosis in GC cells by regulating the miR-140-5p/UBR5 axis.

6.
Carbohydr Polym ; 299: 120184, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36876799

RESUMO

Tooth extraction commonly causes uncontrolled bleeding, loss of blood clots, and bacterial infection, leading to the dry socket and bone resorption. Thus, it is highly attractive to design a bio-multifunctional scaffold with outstanding antimicrobial, hemostatic, and osteogenic performances for avoiding dry sockets in clinical applications. Herein, alginate (AG)/quaternized chitosan (Qch)/diatomite (Di) sponges were fabricated via electrostatic interaction, Ca2+ cross-linking, as well as lyophilization methods. The composite sponges are facilely made into the shape of the tooth root, which could be well integrated into the alveolar fossa. The sponge shows a highly interconnected and hierarchical porous structure at the macro/micro/nano levels. The prepared sponges also possess enhanced hemostatic and antibacterial abilities. Moreover, in vitro cellular assessment indicates that the developed sponges have favorable cytocompatibility and significantly facilitate osteogenesis by upregulating the formation of alkaline phosphatase and calcium nodules. The designed bio-multifunctional sponges display great potential for trauma treatment after tooth extraction.


Assuntos
Alvéolo Seco , Hemostáticos , Humanos , Osteogênese , Antibacterianos , Alginatos , Hemostasia
8.
Cancer Biomark ; 27(1): 29-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31658042

RESUMO

BACKGROUND: Tissue biopsy remains the conventional technique for tumor genotyping. The main limitations are it is invasive and provides only partial snapshot during disease progression. Liquid biopsy approaches via plasma and urine are possible alternatives, and the current study aims to provide comparative analyses for plasma and urine derived disease genotyping. METHODS: Blood and urine specimens were collected from 150 individuals with metastatic colorectal cancer (mCRC). Patients had multiple metastases and advanced stages of cancer. Common genetic mutations including KRAS and BRAF genetic abnormalities were evaluated. Patients were also serially monitored and compared. RESULTS: In all cases, plasma and urine cell free DNA were successfully recovered and were of good quality for genetic analysis. Median recovered DNA from both urine and plasma samples were higher in mCRC patients than healthy volunteers indicating disease associations. Among the identified mutations, matched tumor tissue profiles compared to results from plasma ctDNA was 92%. For urine cell free DNA, the concordance among the identified mutations was 91%. Both sample types were closely matched to reference standards of tissue biopsy and indicated good clinical utility. Serial measurements indicated trends within each patient group that was linked with disease outcome. CONCLUSIONS: In the current study, our data indicated that both plasma and urine cell free DNA can be utilized to address possible disease progression in colorectal cancer patients. More importantly, this also provide risk stratifications that correlated to disease outcome. This can potentially aid in early clinical intervention for patients with possibly worse outcomes.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/urina , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/urina , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Neoplasias Colorretais/urina , Intervalo Livre de Doença , Feminino , Humanos , Biópsia Líquida , Masculino , Pessoa de Meia-Idade , Mutação
9.
Huan Jing Ke Xue ; 35(7): 2771-6, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25244867

RESUMO

In order to study the effect of conservation tillage on soil CO2 and N2O emissions in the following crop-growing season, field experiments were conducted in the winter wheat-growing season. Four treatments were conventional tillage (T), no-tillage with no straw cover (NT), no-tillage with straw cover (NTS), and conventional tillage with straw incorporation (TS), respectively. The CO2 and N2O fluxes were measured using a static chamber-gas chromatograph technique. The results showed that in the following winter wheat-growing season, conservation tillage did not change the seasonal pattern of CO2 and N2O emission fluxes from soil, and had no significant effect on crop biomass. Conservation tillage significantly reduced the accumulative amount of CO2 and N2O. Compared with the T treatment, the accumulative amount of CO2 under TS, NT, and NTS treatments were reduced by 5.95% (P = 0.132), 12.94% (P = 0.007), and 13.91% (P = 0.004), respectively, and the accumulative amount of N2O were significantly reduced by 31.23% (P = 0.000), 61.29% (P = 0.000), and 33.08% (P = 0.000), respectively. Our findings suggest that conservation tillage significantly reduced CO2 and N2O emission from soil in the following winter wheat-growing season.


Assuntos
Agricultura/métodos , Dióxido de Carbono/análise , Óxido Nitroso/análise , Solo/química , Estações do Ano , Triticum/crescimento & desenvolvimento
10.
Mol Plant Pathol ; 12(2): 187-201, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21199568

RESUMO

Oomycete pathogens cause severe damage to a wide range of agriculturally important crops and natural ecosystems. They represent a unique group of plant pathogens that are evolutionarily distant from true fungi. In this study, we established a new plant-oomycete pathosystem in which the broad host range pathogen Phytophthora parasitica was demonstrated to be capable of interacting compatibly with the model plant Arabidopsis thaliana. Water-soaked lesions developed on leaves within 3 days and numerous sporangia formed within 5 days post-inoculation of P. parasitica zoospores. Cytological characterization showed that P. parasitica developed appressoria-like swellings and penetrated epidermal cells directly and preferably at the junction between anticlinal host cell walls. Multiple haustoria-like structures formed in both epidermal cells and mesophyll cells 1 day post-inoculation of zoospores. Pathogenicity assays of 25 A. thaliana ecotypes with six P. parasitica strains indicated the presence of a natural variation in host specificity between A. thaliana and P. parasitica. Most ecotypes were highly susceptible to P. parasitica strains Pp014, Pp016 and Pp025, but resistant to strains Pp008 and Pp009, with the frequent appearance of cell wall deposition and active defence response-based cell necrosis. Gene expression and comparative transcriptomic analysis further confirmed the compatible interaction by the identification of up-regulated genes in A. thaliana which were characteristic of biotic stress. The established A. thaliana-P. parasitica pathosystem expands the model systems investigating oomycete-plant interactions, and will facilitate a full understanding of Phytophthora biology and pathology.


Assuntos
Arabidopsis/parasitologia , Especificidade de Hospedeiro , Phytophthora/fisiologia , Doenças das Plantas/parasitologia , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/ultraestrutura , Contagem de Colônia Microbiana , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Especificidade de Hospedeiro/genética , Phytophthora/citologia , Folhas de Planta/parasitologia , Folhas de Planta/ultraestrutura , Raízes de Plantas/citologia , Raízes de Plantas/parasitologia , Regulação para Cima/genética
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