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1.
Zhonghua Wai Ke Za Zhi ; 61(3): 256-259, 2023 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-36650972

RESUMO

Endovascular treatment of Stanford type B aortic dissection (type B dissection) has been widely used. There will be complications such as aortic dilatation, which will lead to poor prognosis of some patients. With more in-depth researches, it was found that there was a possible correlation between the prognosis of type B dissection and tears, such as the increasing of aortic diameter would be faster with longer tears, and the location of the tear will affect the thrombosis of the false lumen. Studies on hemodynamics have also found that different characteristics of tears of aortic dissection can cause changes in the pressure, blood flow rate and blood capacity in the true and false lumens recently. The hemodynamic changes can be used to predict the prognosis of type B dissection. The main characteristics of tears included the size, position, number of tears, residual tears and stent graft induced new entry. Describing the effect of tear characteristics on the development of type B dissection, can provide the basis for the clinical treatment and further research of type B dissection.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Trombose , Humanos , Dissecção Aórtica/cirurgia , Hemodinâmica , Prognóstico , Implante de Prótese Vascular/efeitos adversos , Trombose/etiologia , Procedimentos Endovasculares/efeitos adversos , Aneurisma da Aorta Torácica/cirurgia , Stents/efeitos adversos , Resultado do Tratamento
2.
J Phys Condens Matter ; 32(47): 475001, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870810

RESUMO

Monolayer C2N has been successfully synthesized. To explore the enhancement of its stability and the expansion of its potential applications in electronics and optoelectronics, a vertical van der Waals heterostructure is constructed by C2N monolayer integrated with h-BN monolayer. The first-principles calculations based on the density functional theory show that this structure possesses a type-II band alignment with a smaller direct band gap and lager band offsets, suggesting that photo-generated electron-hole pairs can be well spatially separated, and thus an excellent photoelectric and photovoltaic material can be obtained. Also shown is that the electronic properties of such a heterostructure can be effectively regulated by a vertical strain and external electric field. For example, under compressive strain or forward electric field, its band gap can be significantly reduced to enhance light-excitation electron transition further, meanwhile the feature of direct band-gap and large band offsets is always well-preserved. Furthermore, it is found that the intrinsic heterostructure holds a wide optic adsorption range and large adsorption coefficient, and the applied compressive strain or a positive electric field can lead to a wide and high main absorption peak across the near-infrared, visible light, and ultraviolet region, implying that a tuned heterostructure has more promising applications in optoelectronics.

3.
J Phys Condens Matter ; 30(44): 445802, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30132442

RESUMO

Magnetic nanomaterials with the desirable nature are the basis for developing future spintronic devices, and research for them is of fundamental interest. Here, we explore the realization of half-metallicity and magnetic phase transition for phagraphene nanoribbons in virtue of functional groups (OH and CN) with different coverage fractions and external electric fields. The first-principles calculations show that a single-edge CN functionalization only makes a intrinsic spin-degenerate semiconducting ribbon converted to a quasi-metal or metal, while a single-edge OH modification leads to an occurrence of the half-semiconducting nature regardless of the coverage fraction of groups. Interestingly, the half-metal behavior for the CN and OH double-edge modified ribbons can be achieved either in the zero-electric-field intrinsic state for most of functionalized systems or at a very low electric field, 0.1 V Å-1. More importantly, the observed critical electric field for the transition from ferromagnetic to nonmagnetic phase is lowered significantly almost for all systems, this benefits to design a low electric-field-controlling magnetic switch which can reversibly work between both magnetic and nonmagnetic states. The calculated Gibbs free energy confirms that the group-modified ribbons generally hold a more favorable energy stability in most of the cases, facilitating likely experimental realization.

4.
Phys Chem Chem Phys ; 19(14): 9528-9536, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28345700

RESUMO

2D penta-graphene sheets were cut along typical crystallographic orientations in order to construct various penta-graphene nanoribbon (P-GNR) models, and their electronic structures and magnetic properties were systemically investigated. It was demonstrated that P-GNRs are very versatile with rich and unique electronic and magnetic properties. In particular, bipolar magnetic semiconducting features can be achieved in the ferromagnetic state for all magnetic P-GNRs, which makes P-GNRs valuable for developing next-generation information storage devices. More interestingly, studies on the electric-magnetic coupling revealed that an applied transverse electric field can transform a P-GNR from a magnetic semiconductor to a half-metal with a wide band gap of 0.88 eV, which can achieve complete spin filtering even at room temperature. Important advantages of magnetism over graphene nanoribbons are thus expected.

5.
Phys Chem Chem Phys ; 19(6): 4469-4477, 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28120954

RESUMO

The structural and magneto-electronic properties and electric field-mediated effects for zigzag boron nitride nanoribbons (ZBNNRs) terminated with typical transition metal (TM) atoms (TM-ZBNNRs) are investigated systematically. Our work demonstrates that ZBNNRs form strong bonds with all studied termination atoms. The strong interactions and large orbital hybridizations of TM atoms to the ribbon make the magnetic anisotropy enhanced significantly, favorably to stabilize magnetism. The spin-split features for such hybridized structures can occur in most of the magnetic configurations, leading to a large magnetic moment. Higher spin polarization can be found in the ferromagnetic (FM) state. In particular, spin polarization exceeding 90% at the Fermi level can be achieved for Fe-ZBNNRs when an in-plane transverse electric field is applied. These results might be of interest from the prospects of both fundamental science and its potential applications.

6.
J Biol Regul Homeost Agents ; 29(2): 367-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26122224

RESUMO

An increasing number of people die from breast cancer every year. Consequently, more research has been concentrated on the study of this type of tumour, and miR-373 resulted as an important gene for treating breast cancer. To explore the influence of miR-373 on the invasion and migration of breast cancer and the expression level of target gene TXNIP, a set of therapeutic methods were designed based on miR-373. The transfection was performed using miR-373 inhibitor; the concentration of miR-373 was controlled by inhibitor, and it was transfected into MCF-7 cell by lipofectin. Fluorescent quantitative polymerase chain reaction was used to detect the expression level of miR-373 in cells after transfection as well as that of Caspase-3 and Caspase-8. MTT assay was used to detect the influence of miR-373 inhibitor on MCF-7 cells. The expression quantity of miR-373 in cell and tissue of breast cancer with high-low invasion and migration ability was detected by qRT-PCR (quantitative real-time polymerase chain reaction), thus the influence of the expression quantity of miR-373 on the invasion and migration of cell was determined. The expression of miR-373, EMT and TXNIP was determined by Western blot. Through the identification of proteomics and bioinformatics, it was finally found that TXNIP was regulated by miR-373. The protein expression level of TXNIP was negatively correlated with the level of miR-373. Thus it was concluded that miR-373 could promote the invasion and migration of breast cancer. In addition, in the tissue and cell of breast cancer with different invasion and migration abilities, the expression level of TXNIP was negatively correlated with the level of miR-373.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Transporte/fisiologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Proteínas de Neoplasias/fisiologia , RNA Neoplásico/fisiologia , Adenocarcinoma/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Caspase 3/biossíntese , Caspase 3/genética , Caspase 9/biossíntese , Caspase 9/genética , Linhagem Celular Tumoral , Feminino , Humanos , MicroRNAs/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , RNA Neoplásico/antagonistas & inibidores , RNA Neoplásico/biossíntese , Transfecção , Regulação para Cima
7.
Immunol Invest ; 44(6): 521-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26207789

RESUMO

Total glucoside of paeony (TGP), extracted from the root of Paeonia Lactiflora, has been known to show anti-inflammatory, anti-oxidative, hepato-protective and immuno-regulatory activities. The aim of this present study was to determine the anti-tumor effect of TGP against N-nitrosodiethylamine (DEN)-induced hepatocellular carcinoma (HCC) in rats, and to find the related mechanisms. Rat HCC model was established by intragastrically administrating with DEN (8 mg/kg). We found the number of tumor nodules and the index of liver and spleen were increased in the model group compared with the normal group, and was significantly decreased by TGP. Additionally, TGP obviously improved the hepatic pathological lesions induced by DEN, and decreased the elevated levels of serum alanine aminotransferase (ALT), glutamic oxalacetic transaminase (AST), alkaline phosphatase (ALP) and alpha fetoprotein (AFP) by DEN. Moreover, TGP decreased the level of B cell-activating factor (BAFF) and the proportion of IL-10-producing regulatory B cells (Bregs), and the decrease of BAFF by TGP is positively correlated to the decrease of IL-10-producing Bregs by TGP. These results suggest that TGP had a good therapeutic action on DEN-induced HCC rats, which might be due to its down-regulation of Bregs through reducing the level of BAFF.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Linfócitos B Reguladores/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Glucosídeos/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Paeonia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Antineoplásicos Fitogênicos/farmacologia , Aspartato Aminotransferases/sangue , Fator Ativador de Células B/sangue , Linfócitos B Reguladores/imunologia , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Dietilnitrosamina , Regulação para Baixo , Glucosídeos/farmacologia , Interleucina-10/imunologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Fitoterapia , Ratos Sprague-Dawley
8.
J Toxicol Environ Health ; 45(1): 75-82, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7752290

RESUMO

The effects of NO2 or SO2 on the bronchopulmonary reactions induced by Candida albicans in guinea pigs were evaluated. Thirty-six guinea pigs (3 groups of 12 animals each) were sensitized with intraperitoneal injection of 10 mg of C. albicans, given twice. Two groups of animals were exposed to about 5 ppm of NO2 or SO2 for 4 h/d, 5 d/wk; this exposure was conducted a total of 30 times during the study. The third group served as the control and was not exposed to these pollutants. Two weeks after the second sensitization, all the animals were subjected to inhalation exposure to C. albicans. For 42 h after the antigen challenge, the respiratory rates and expiration/inspiration ratios of the animals were automatically monitored. The number of animals showing tachypnea was significantly higher in the NO2 exposure group than in the control from 15 h after antigen challenge. In the SO2 exposure group, the number of animals showing prolonged expiration or prolonged inspiration, or both, was significantly higher than that in the control group, and the symptoms were observed from approximately 15 h after antigen challenge. These findings showed that delayed-type dyspneic symptoms in guinea pigs were increased by exposure to NO2 or SO2, although the symptoms and degree of dyspnea were different for the two gases.


Assuntos
Candida albicans/imunologia , Dióxido de Nitrogênio/toxicidade , Respiração/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Dióxido de Enxofre/toxicidade , Administração por Inalação , Poluentes Atmosféricos/toxicidade , Animais , Candida albicans/efeitos dos fármacos , Dispneia/induzido quimicamente , Cobaias , Masculino , Dióxido de Nitrogênio/administração & dosagem , Distribuição Aleatória , Dióxido de Enxofre/administração & dosagem
9.
J Toxicol Environ Health ; 37(2): 265-75, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1404485

RESUMO

An automated system was developed for evaluating changes in respiratory symptoms in guinea pigs over a long period with a personal computer. The data on breathing curves obtained with a body plethysmograph were analyzed to determine respiratory rate, expiration/inspiration ratio, ventilation ratio, and other parameters. With this system, respiratory changes in guinea pigs, such as increase or decrease of respiratory rate, expiration/inspiration ratio, and ventilation ratio, and death of animals could be easily observed. Investigation of delayed respiratory response to Candida albicans in sensitized guinea pigs and of the effects of SO2 or NO2 exposures on its response was carried out using this system. Respiratory changes in delayed respiratory response were mostly increased respiration rate and succeeding expiratory prolongation being noted just before death. In the influences of SO2 or NO2 exposure on delayed respiratory response, increase of respiratory rate in NO2 and expiratory and inspiratory prolongation in SO2 were found. This system should prove useful for evaluating changes in respiratory symptoms due to toxic agents, medicines, and air pollutants in small animals.


Assuntos
Asma/fisiopatologia , Processamento Eletrônico de Dados , Microcomputadores , Respiração , Animais , Candidíase/fisiopatologia , Cobaias , Pneumopatias Fúngicas/fisiopatologia , Masculino , Pletismografia , Transdutores de Pressão
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