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1.
ACS Omega ; 8(42): 39154-39167, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37901580

RESUMO

The flattening of nanoscale pores is a crucial step in the process of anthracite graphitization, which primarily occurs due to lithostatic pressure or tectonic stress. Anthracite, a highly metamorphosed form of carbonaceous material, is a primary component of artificial graphite, but its availability is limited in China. Therefore, it is necessary to investigate the graphitization of low metamorphic coal. Note that the pores of deformed coal are substantially compressed, and the evolution of macromolecular structure is accelerated owing to strong tectonic extrusion and shearing action. Herein, the feasibility analysis of coal-based graphite at temperatures of 2200 and 2600 °C was investigated using mylonitized meager coal (YA-M; Ro,max = 2.34%), which exhibits the most intense deformation intensity, and it was compared with undeformed coal (YA-U; Ro,max = 1.87%) from the same coal seam. Results indicate that YA-U primarily consists of cylindrical pores with an average pore diameter of 10 nm, while YA-M exhibits extensive fine bottleneck and parallel plate pores with an average pore size of ∼4 nm. Additionally, interlayer spacing decreases from 0.3592 nm in YA-U to 0.3575 nm in YA-M, while crystallite height increases from 1.9633 nm in YA-U to 2.1424 nm in YA-M. The undeformed coal YA-U exhibits short and disordered aromatic fringes with a localized turbostratic structure that hinders graphitization. In contrast, YA-M exhibits more and longer localized fringe pairs arranged in parallel with improved structural ordering, indicating a favorable environment for graphitization. Ductile deformation narrows the pore diameter distribution, causing deformation pores on the mylonitic granules' surface to close, shrink directionally, collapse, or connect, resulting in obvious flattening characteristics of nanoscale. Based on these results, the graphitization degree of the graphitized products YA-GM-2200 and YA-GM-2600 was 80.23% and 88.37%, respectively, with interlayer spacings of 0.3371 and 0.3364 nm, indicating that these products have entered the semigraphite (medium graphitization) and graphite range, respectively. In contrast, the graphitization degree of YA-GU-2200 and YA-GU-2600 was only 51.16% and 56.98%, respectively, indicating that they have only progressed from anthracite to meta-anthracite (the preliminary graphitization stage). These findings confirm the view that the shear stress generated by the geological age flattens the pores of mylonitized meager coal and optimizes the aromatic lattice arrangement and orientation, facilitating graphitization and lowering the graphitization temperature (from 2800 to 2200 °C). Deformed coal is soft and can be easily crushed into powdered form using the human hand, making it less suitable for transportation. Additionally, owing to the unfavorable separation of minerals and lower hydrocarbon-generating potential, deformed coal application potential and price are consistently lower than those of undeformed coal. However, deformed coal is widely distributed in various coal measures in China, making these research findings valuable in promoting the high value-added utilization of low-rank deformed coal resources and expanding the carbon source of coal-based graphite materials.

2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(8): 1234-1242, 2023 Aug 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37875364

RESUMO

OBJECTIVES: Many studies have shown that the quality of life for patients with atrial fibrillation (AF) is significantly impaired, but the impact on family function is still unclear. This study aims to evaluate the family function and quality of life in patients with AF using scales, to analyze the correlation between family function and quality of life, and to predict the influencing factors of quality of life. METHODS: A total of 223 patients with AF who were admitted to the Department of Cardiology and General Medicine of the Lanzhou University Second Hospital from January 1, 2021 to May 1, 2022, were selected as research subjects, the general information of patients with AF were collected via a questionnaire, the family function and quality of life were assessed by the Family Assessment Device (FAD) and Atrial Fibrillation Effect on Quality-of-Life (AFEQT) scale. The patients were divided into a non-family functional disorder group and a family functional disorder group on the basis of their FAD scores. The above data were analyzed using SPSS 26.0 statistical software. RESULTS: Among the 223 patients, 64 (28.70%) were in the non-family functional disorder group, and 159 (71.30%) were in the family functional disorder group. The total score of FAD and scores of all dimensions in the family functional disorder group were higher than those in the non-family functional disorder group (all P<0.01). AFEQT total score and symptoms, treatment concerns and daily activities in the non-family functional disorder group were significantly higher than those in the family functional disorder group (all P<0.01). The Pearson linear analysis showed that there was a linear negative correlation between the total score and each dimension of FAD with the total score and each dimension of AFEQT (all P<0.01). The variables with statistical significance in the univariate analysis were included in the multiple linear regression analysis, and the result showed that female, and the problem solving, role, affective involvement, and general functioning dimensions of family function had an impact on the quality of life (all P<0.01). CONCLUSIONS: Most patients with AF have different degrees of family dysfunction. The quality of life in patients with family functional disorder group is generally low. Female, and the problem solving, role, affective involvement, and general functioning of family function have a significant impact on the quality of life in patients with AF. In clinical treatment of AF, attention should be paid to the family function of patients, and family members can be involved in clinical intervention to improve family function and improve the quality of life.


Assuntos
Fibrilação Atrial , Humanos , Feminino , Qualidade de Vida , Pacientes , Inquéritos e Questionários
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(2): 257-263, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37157073

RESUMO

Objective To examine the antiplatelet effect of ticagrelor by microfluidic chip and flow cytometry under shear stress in vitro. Methods Microfluidic chip was used to examine the effect of ticagrelor on platelet aggregation at the shear rates of 300/s and 1500/s.We adopted the surface coverage of platelet aggregation to calculate the half inhibition rate of ticagrelor.The inhibitory effect of ticagrelor on ADP-induced platelet aggregation was verified by optical turbidimetry.Microfluidic chip was used to construct an in vitro vascular stenosis model,with which the platelet reactivity under high shear rate was determined.Furthermore,the effect of ticagrelor on the expression of fibrinogen receptor (PAC-1) and P-selectin (CD62P) on platelet membrane activated by high shear rate was analyzed by flow cytometry. Results At the shear rates of 300/s and 1500/s,ticagrelor inhibited platelet aggregation in a concentration-dependent manner,and the inhibition at 300/s was stronger than that at 1500/s (both P<0.001).Ticagrelor at a concentration ≥4 µmol/L almost completely inhibited platelet aggregation.The inhibition of ADP-induced platelet aggregation by ticagrelor was similar to the results under flow conditions and also in a concentration-dependent manner.Ticagrelor inhibited the expression of PAC-1 and CD62P. Conclusion We employed microfluidic chip to analyze platelet aggregation and flow cytometry to detect platelet activation,which can reveal the responses of different patients to ticagrelor.


Assuntos
Microfluídica , Inibidores da Agregação Plaquetária , Humanos , Ticagrelor/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Citometria de Fluxo/métodos , Agregação Plaquetária
4.
Radiat Res ; 198(6): 590-598, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481803

RESUMO

Cardiomyocyte apoptosis is involved in the pathogenesis of radiation-induced heart disease, but the underlying epigenetic mechanism remains elusive. We evaluated the potential mediating role of males absent on the first (MOF) in the association between epigenetic activation of p53 lysine 120 (p53K120) and X-ray radiation-induced apoptosis in H9c2 cells. H9c2 cells were pretreated for 24 h with the MOF inhibitor MG149 after 4 Gy irradiation, followed by assessment of cell proliferation, injury, and apoptosis. MOF expression was upregulated by X-ray radiation. MG149 suppressed the proliferation inhibition, reduction of mitochondrial membrane potential, ROS production, and cell apoptosis. MG149 may promote the survival of H9c2 cells via inhibition of MOF-mediated p53K120 acetylation in response to X-ray radiation-induced apoptosis. Our data indicates a MOF-associated epigenetic mechanism in H9c2 cells that promotes attenuation of X-ray radiation-induced injury.


Assuntos
Apoptose , Proteína Supressora de Tumor p53 , Raios X
5.
Cancers (Basel) ; 14(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36497204

RESUMO

The accumulation of oxidative DNA base damage can severely disrupt the integrity of the genome and is strongly associated with the development of cancer. DNA glycosylase is the critical enzyme that initiates the base excision repair (BER) pathway, recognizing and excising damaged bases. The Nei endonuclease VIII-like 3 (NEIL3) is an emerging DNA glycosylase essential in maintaining genome stability. With an in-depth study of the structure and function of NEIL3, we found that it has properties related to the process of base damage repair. For example, it not only prefers the base damage of single-stranded DNA (ssDNA), G-quadruplex and DNA interstrand crosslinks (ICLs), but also participates in the maintenance of replication fork stability and telomere integrity. In addition, NEIL3 is strongly associated with the progression of cancers and cardiovascular and neurological diseases, is incredibly significantly overexpressed in cancers, and may become an independent prognostic marker for cancer patients. Interestingly, circNEIL3, a circular RNA of exon-encoded origin by NEIL3, also promotes the development of multiple cancers. In this review, we have summarized the structure and the characteristics of NEIL3 to repair base damage. We have focused on NEIL3 and circNEIL3 in cancer development, progression and prognosis.

6.
Neoplasma ; 69(6): 1253-1269, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35951454

RESUMO

Osteopontin (OPN) is a multifunctional phosphorylated glycoprotein that is expressed at significantly elevated levels in various cancers. OPN overexpression is closely associated with the development of cancer progression such as proliferation, metastasis, angiogenesis, apoptosis resistance, drug resistance, and immunosuppression, and may also be an independent prognostic biomarker for a variety of cancers. This review broadly summarizes the mechanisms that regulate the expression of downstream oncogenic molecules after OPN binds to integrin receptors or CD44 receptors, which involve a complex intracellular "signaling traffic network" (including key kinases, signaling pathways, and transcription factors). In addition, we review the prognostic value of OPN, OPN synergistic downstream oncogenic molecules in the female breast, non-small cell lung, prostate, colorectal, gastric, and hepatocellular carcinomas. The prognostic value of OPN in tissues or blood may vary due to differences in study subjects or detection methods, and this aspect of the study requires further systematization with a view to applying the detection of OPN to clinical applications. Importantly, based on the fact that the oncogenic effect of OPN correlates with the expression of the above-mentioned oncogenic molecules, this work may provide some help in the study of combination therapy targeting OPN and the above-mentioned oncogenic molecules.


Assuntos
Neoplasias , Osteopontina , Humanos , Carcinogênese , Carcinógenos , Prognóstico
7.
Nanotechnology ; 33(45)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35976804

RESUMO

Coal-based graphene sheets (GS) and coal-based graphene quantum dots (GQDs) are usually prepared separately. In this paper, symbiosis of coal-based GS and coal-based GQDs was successfully prepared with our proposed preparation method by using three raw coals with different reflectance (collected from Qinshui coalfield, Shanxi Province) as carbon sources. The results showed that coal-based GS and coal-based GQDs can exist stably in the symbiosis and are distributed in different layers, and the GQDs are freely distributed between layers of GS. The average number of GS (Nave) in the three symbiosis is about 7 and the average interlayer spacing (d002) is about 0.3887 nm. The average diameter of GQDs in the three symbiosis is about 4.255 nm and the averaged002is about 0.230 nm. The averageNaveof the three symbiosis was about 3 and the averaged002is about 0.361 nm. The morphology and crystal parameters of symbiosis is more similar to that of graphene, the elements are only carbon and oxygen. In the prepared symbiosis, the higher the reflectance of raw coal, the smoother the lattice skeleton and the less vortex-layer structure of GS, and the larger the diameter and the denser the six membered ring of GQDs. The C and O functional groups of the prepared symbionts are similar. The higher the reflectance of coal, the higher the content of C-C/C=C. Under ultraviolet light, the prepared products all emit blue, and the higher the reflectance of coal, the higher the ultraviolet absorption, and the stronger the fluorescence intensity.

8.
Org Lett ; 24(15): 2832-2836, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35394282

RESUMO

A copper-catalyzed 1,4-protosilylation of α-alkynyl-enones to form the functionalized chiral homoallenylsilanes was developed. In the presence of a chiral monopyridine oxazoline ligand, a variety of trisubstituted allene derivatives bearing a contiguous stereogenic center and axis were prepared in good yields with excellent enantioselectivities and diastereoselectivities.

9.
Chem Cent J ; 9: 8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25745512

RESUMO

BACKGROUND: The enzyme-linked immunosorbent assay (ELISA) has been used for diagnosing medical and plant pathologies. In addition, it is used for quality-control evaluations in various industries. The ELISA is the simplest method for obtaining excellent results; however, it is time consuming because the immunoreagents interact only on the contact surfaces. Antibody-labeled magnetic particles can be dispersed in a solution to yield a pseudohomogeneous reaction with antigens which improved the efficiency of immunoreaction, and can be easily separated from the unreactive substances by applying a magnetic force. We used a homemade magnetic microplate, functional magnetic particles (MPs) and enzyme-labeled secondary antibody to perform the sandwich ELISA successfully. RESULTS: Using antibody-labeled MPs enabled reducing the analysis time to one-third of that required in using a conventional ELISA. The secondary antibody conjugated with horseradish peroxidase (HRP) was affinity-bound to the analyte (IgG in this study). The calibration curve was established according to the measured absorbance of the 3, 3', 5, 5'-tetramethybezidine-HRP reaction products versus the concentrations of standard IgG. The linear range of IgG detection was 114 ng/mL-3.5 ng/mL. The limit of detection (LOD) of IgG was 3.4 ng/mL. The recovery and coefficient of variation were 100% (±7%) and 116% (±4%) for the spiked concentrations of 56.8 ng/mL and 14.2 ng/mL, respectively. CONCLUSION: Pseudohomogeneous reactions can be performed using functional MPs and a magnetic microplate. Using antibody-labeled MPs, the analysis time can be reduced to one-third of that required in using a conventional ELISA. The substrate-enzyme reaction products can be easily transferred to another microplate, and their absorbance can be measured without interference by light scattering caused by magnetic microbeads. This method demonstrates great potential for detecting other biomarkers and in biochemical applications. Graphical AbstractA magnetic ELISA with convenient magnetic microplate.

10.
Huan Jing Ke Xue ; 35(9): 3422-9, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25518660

RESUMO

This research described the heterogeneous reactions of persulfate with different particle sizes of zero-valent iron (including 1 mm-ZVI,150 µm-ZVI,50 nm-ZVI) for degradation of acid orange 7(AO7) , and studied the kinetics and intermediate products of AO7 under these systems. The results demonstrated that these three types of ZVI were efficient in promoting the degradation of AO7, the degradation efficiencies of AO7 were 43% , 97% , and 100% within 90 min respectively, in the 1 mm-ZVI,150 µm-ZVI and 50 nm- ZVI systems, respectively. With the results of kinetic fitting models, the pseudo first-order kinetics exhibited better fitting results in the 1 mm-ZVI,150 µm-ZVI systems, while the second-order kinetics exhibited better fitting results in the 50 nm-ZVI system. And the different ZVI types exhibited difference on the AO7 degradation rate constant, which ranged as 50 nm-ZVI > 150 µm-ZVI > 1 mm-ZVI. The iron corrosion products coating on the ZVI after reaction were composed of α-Fe2 O3 and some Fe3O4 in the 1 mm-ZVI system while that consisted of Fe3O4 and α-Fe2O3, FeOOH respectively, in thel50 µm-ZVI and 50 nm-ZVI systems,. Which were identified by scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) and Raman spectroscopy. Some intermediate products, including 2-naphthalenol, 2-methylphenol, 4-ethyl- 3-methyl-phenol, isoindole- 1,3-dione and phthalic acid et al. were identified by GC/MS measurement. Both UV-vis absorbance spectra and GC/MS determination indicated that there was difference in degradation paths of AO7 between the three systems.


Assuntos
Compostos Azo/química , Benzenossulfonatos/química , Ferro/química , Tamanho da Partícula , Sulfatos/química , Cinética , Modelos Teóricos
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