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1.
Mol Cell Biochem ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720056

RESUMO

Gastric cancer (GC) stands as one of the most formidable malignancies worldwide. It is well-established that miRNAs play a crucial role in the initiation and progression of various human cancers. Among these, miR-99a-3p has been implicated in the pathogenesis of GC. In the context of our study, we embarked on the comprehensive examination of miR-99a-3p expression in GC cells. Additionally, we sought to establish a correlation between miR-99a-3p expression levels and the overall survival (OS) of GC patients, and our findings hinted at its potential role in predicting an unfavorable prognosis. To further investigate the functional implications of miR-99a-3p in GC, we conducted a series of cell-based experiments after successfully knocking down miR-99a-3p. These investigations uncovered a substantial inhibition of cellular events associated with tumor progression. Moreover, employing TargetScan, we identified Tripartite motif-containing protein 21 (TRIM21) as a putative target with a binding site for miR-99a-3p. Subsequent dual-luciferase reporter gene assay confirmed the direct interaction between miR-99a-3p and TRIM21. Western blot analysis validated the alteration in TRIM21 expression levels, revealing an upregulation upon miR-99a-3p knockdown. Building on these molecular findings, we extended our investigations to human GC tissues, where we observed a downregulation of TRIM21, which, notably, correlated with shorter overall survival. Lastly, to further solidify our conclusions, we conducted a series of in vitro and in vivo rescue experiments, collectively suggesting that miR-99a-3p promoted the progression of GC cells through the downregulation of TRIM21. In summary, our study comprehensively explored the role of miR-99a-3p in GC, revealing its association with unfavorable patient outcomes, functional implications in tumor progression, and a direct regulatory relationship with TRIM21. These findings collectively underscore the significance of miR-99a-3p in the pathogenesis of GC and present a potential therapeutic avenue for further investigation.

2.
Ecotoxicol Environ Saf ; 179: 249-256, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054378

RESUMO

The functional role of 1,25-vitamin D3 in cooking oil fumes (COFs)-derived PM2.5-induced cell damage is largely unexplored. The present study investigated the protective role of 1,25-vitamin D3 against cell injury by possible involvement of JAK/STAT and NF-κB signaling pathways in cardiomyocytes. Cell viability was measured using CCK-8 assay, and cell apoptosis was analyzed by flow cytometry, qRT-PCR and Western blot in cultured rat neonatal cardiomyocytes treated with 1,25-vitamin D3 and COFs-derived PM2.5. Expressions of JAK/STAT and NF-κB signaling pathway were measured by Western blot. The results suggested that treatment with COFs-derived PM2.5 significantly decreased cell viability and increased apoptosis and oxidative stress in cultured rat neonatal cardiomyocytes. 1,25-vitamin D3 pretreatment alleviated the cell injury by increasing cell viability and decreasing apoptosis in the cardiomyocytes. 1,25-vitamin D3 pretreatment also decreased the ROS level and inflammation in the cardiomyocytes. Furthermore, 1,25-vitamin D3 pretreatment alleviated COFs-derived PM2.5-evoked elevation of JAK/STAT and NF-κB signaling pathways. Our study showed that 1,25-vitamin D3 pretreatment protected cardiomyocytes from COFs-derived PM2.5-induced injury by decreasing ROS, apoptosis and inflammation level via activations of the JAK/STAT and NF-κB signaling pathways.


Assuntos
Poluentes Atmosféricos/toxicidade , Anti-Inflamatórios/farmacologia , Colecalciferol/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Culinária/métodos , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Ratos , Transdução de Sinais/efeitos dos fármacos
3.
J Nanosci Nanotechnol ; 12(8): 6467-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962766

RESUMO

We report an atomistic simulation of spin dependent charge transport in zigzag graphene nanoribbons with 4 zigzag chains doped by a Beryllium atom on one edge. The spin dependent density functional theory with norm-conserving atomic basis set is employed to describe the system and the current versus voltage behavior is calculated by the nonequilibrium Green's function method for quantum transport. The Be impurity atom suppresses the local magnetization near the edge and the transmitted charge current becomes spin polarized accordingly. Both spin-up and spin-down transmission spectra are modified significantly but in different ways. Distinguished from the previous doping results of other impurity elements, here we observe negative differential resistance for only one of the spins in the nonlinear transport regime below bias 1.5 V. Molecular projected Hamiltonian energy spectrum near the impurity shows that the impurity removes the energy degeneracy of spin in perfect ribbon. The current versus voltage shows semiconductor behavior with fluctuating spin polarization of amplitude up to 37%.

4.
Front Chem ; 9: 671720, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996764

RESUMO

Free-standing GaN substrates are urgently needed to fabricate high-power GaN-based devices. In this study, 2-inch free-standing GaN substrates with a thickness of ~250 µm were successfully fabricated on double-polished sapphire substrates, by taking advantage of a combined buffer layer using hydride vapor phase epitaxy (HVPE) and the laser lift-off technique. Such combined buffer layer intentionally introduced a thin AlN layer, using a mix of physical and chemical vapor deposition at a relatively low temperature, a 3-dimensional GaN interlayer grown under excess ambient H2, and a coalescent GaN layer. It was found that the cracks in the epitaxial GaN layer could be effectively suppressed due to the large size and orderly orientation of the AlN nucleus caused by pre-annealing treatment. With the addition of a 3D GaN interlayer, the crystal quality of the GaN epitaxial films was further improved. The 250-µm thick GaN film showed an improved crystalline quality. The full width at half-maximums for GaN (002) and GaN (102), respectively dropped from 245 and 412 to 123 and 151 arcsec, relative to those without the 3D GaN interlayer. The underlying mechanisms for the improvement of crystal quality were assessed. This method may provide a practical route for fabricating free-standing GaN substrates at low cost with HVPE.

5.
Anatol J Cardiol ; 15(6): 496-501, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25550177

RESUMO

OBJECTIVE: Dysfunction of cardiac autonomic nerve system is considered as one of risk factors for coronary atherosclerotic heart disease. Heart rate variability (HRV) has been used to study the correlation between damage of coronary artery and dysfunction of autonomic nervous system. We hypothesize the correlation between damage of coronary artery and dysfunction of autonomic nervous system by HRV among subjects with stable angina. METHODS: A 236 subjects who diagnosed as stable angina pectoris by elective coronary angiography, were divided into two groups by Gensini score system (GS):GS≤32 (GS1) and GS2>32 (GS2). Subgroups were divided based on location of stenosis lesions and the number of coronary artery disease. 86 subjects suspicious with stable angina pectoris with normal coronary angiography were selected as the control group. All subjects were received 24-hour ambulatory electrocardiogram and the result of time-domain HRV was analyzed (SDNN, SDANN, SDNNind, RMSSD, PNN50). RESULTS: Compared with control group, SDNN, SDNNind and RMSSD lower in GS1, and SDNN, SDANN, SDNNind, RMSSD, PNN50 lower in GS2; ccompared with GS1, SDNN was lower in GS2. Compared with control group, SDNN in one-vessel, SDNN, SDANN in two-vessel diseased and in three-vessel diseased were lower, and compared with two-vessel diseased, SDNN, SDANN lower in three-vessel diseased. Compared with right-coronary artery diseased, SDNN and SDANN in left-coronary artery diseased group were lower, while compared with lesions in left circumflex, SDNN in lesions in left anterior descending artery lower. CONCLUSION: HRV may be play a crucial role in estimating the correlation between damage of coronary artery and dysfunction of autonomic nerve system.


Assuntos
Angina Pectoris/fisiopatologia , Arritmias Cardíacas/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Frequência Cardíaca , Sistema Nervoso Autônomo , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
6.
Nanoscale ; 6(19): 11121-9, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25214422

RESUMO

We investigate the spin-dependent electric and thermoelectric properties of ferromagnetic zigzag α-graphyne nanoribbons (ZαGNRs) using density-functional theory combined with non-equilibrium Green's function method. A giant magnetoresistance is obtained in the pristine even-width ZαGNRs and can be as high as 10(6)%. However, for the doped systems, a large magnetoresistance behavior may appear in the odd-width ZαGNRs rather than the even-width ones. This suggests that the magnetoresistance can be manipulated in a wide range by the dopants on the edges of ZαGNRs. Another interesting phenomenon is that in the B- and N-doped even-width ZαGNRs the spin Seebeck coefficient is always larger than the charge Seebeck coefficient, and a pure-spin-current thermospin device can be achieved at specific temperatures.

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