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1.
Artigo em Chinês | MEDLINE | ID: mdl-38418182

RESUMO

The difficulty of wound healing in patients is a difficult problem that doctors in all clinical departments may encounter, and there is still no good solution. Resveratrol is a kind of natural active substance, which has anti-inflammatory, antioxidant, antibacterial, and angiogenesis promoting effects, and is a potential drug to promote wound healing. However, the clinical application of resveratrol is limited due to its low bioavailability. In this review, the molecular mechanism of resveratrol in promoting wound healing and its administration methods in wound treatment were reviewed to provide ideas for the redevelopment of resveratrol.


Assuntos
Antioxidantes , Cicatrização , Humanos , Resveratrol/farmacologia , Antioxidantes/farmacologia , Anti-Inflamatórios/farmacologia
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(1): 9-14, 2022 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-34954955

RESUMO

The risk of plague epidemics and relapse of various types of plague foci persists in Inner Mongolia Autonomous Region. For Marmota sibirica plague foci, the animal plague has not been found but antibody has been detected positive. Nowadays, Marmota sibirica has been increasing in population and distribution in China. In bordering countries Mongolia and Russia, the animal plague has been continuously prevalent. For Spermophilus dauricus plague foci, the animal plague has been taken place now and then. Compared to the above foci, the animal plague is most prevalent in Meriones unguiculatus plague foci and frequently spread to humans. Due to higher strain virulence and historical disaster in Marmota sibirica plague foci and Spermophilus dauricus plague foci, plague prevention and control should be strengthened on these foci. In addition to routine surveillance, epidemic dynamics need to be further monitored in these two foci, in order to prevent their relapse and spread to humans.


Assuntos
Epidemias , Peste , Yersinia pestis , Animais , China/epidemiologia , Humanos , Peste/epidemiologia , Peste/prevenção & controle , Prevalência , Sciuridae
3.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(3): 254-261, 2021 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-34286526

RESUMO

OBJECTIVE: To investigate the effectiveness of a new health education pathway for echinococcosis control among primary school students in regions highly prevalent for echinococcosis in China. METHODS: Six primary schools were randomly selected from echinococcosis hyper-endemic regions, with 13 classes assigned to the intervention group and 9 to the control group, and all students in these 21 classes were recruited as the study subjects. Echinococcosis health education was performed through the pathway of assessing the current status-strengthening the building of teaching resources-focusing on practices in the intervention group, while routine health education was given in the control group. A questionnaire survey was performed to assess the score of echinococcosis control knowledge (including theoretical knowledge score and mean daily practical capability score) before and after the health education interventions to evaluate the effectiveness of this new health education pathway for echinococcosis control. RESULTS: The mean score of echinococcosis control knowledge was 68.86 ± 18.70 points at baseline, with the mean theoretical knowledge score of 40.97 ± 10.75 points, and the mean daily practical capability score of 27.89 ± 12.50 points. Clustering analysis showed three types of populations, including "unsatisfactory", "learn and apply creatively", and "rote learning", which accounted for 24.62% (240/975), 45.74% (446/975) and 29.64% (289/975), respectively. The mean score of echinococcosis control knowledge was 81.08 ± 18.15 points in the intervention group during the final assessment, with the mean theoretical knowledge score of 43.65 ± 9.40 points, and the mean daily practical capability score of 37.43 ± 12.22 points, and both were significantly higher relative to baseline (t = -4.201 and -15.202, both P values < 0.01). The mean score of echinococcosis control knowledge was comparable between at baseline (70.55 ± 19.46 points) and final assessment (71.74 ± 19.37 points) in the control group (t = -0.87, P > 0.05). CONCLUSIONS: The awareness of echinococcosis control knowledge is fair among primary school students in echinococcosis hyper-endemic regions; however, the capability of combining theoretical learning and practices requires to be improved. The health education mode based on the pathway of assessing the current status-strengthening the building of teaching resources-focusing on practices seems to remarkably improve the understanding of echinococcosis control knowledge among primary school students in echinococcosis hyper-endemic regions.


Assuntos
Equinococose , Educação em Saúde , China/epidemiologia , Equinococose/epidemiologia , Equinococose/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Instituições Acadêmicas , Estudantes , Inquéritos e Questionários
5.
Phys Chem Chem Phys ; 19(25): 16850-16856, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28627571

RESUMO

In the present study, atomistic simulation reveals that the microscopic mechanism of the relaxation dynamics in amorphous materials is governed by the activating atoms that jump more than half of the average nearest neighbor distance within a given time. Based on the unsupervised machine-learning algorithm, hierarchical clustering analysis shows that the activating atoms are excited in a cooperative and avalanche-like model to form activating units. Correlation analysis suggests that large free volumes facilitate the formation of activating atoms. Interestingly, a fractal correlation is found between the number and size of the activating units, indicating that when the maturation temperature, i.e. percolation threshold, is reached the activating units form a complicated and connected body in space.

6.
Phys Chem Chem Phys ; 19(19): 12056-12063, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28443885

RESUMO

A realistic interatomic potential was first constructed for the Ca-Mg-Ni system and then applied to Monte Carlo simulations to predict the favored composition for metallic glass formation in the ternary system. The simulations not only predict a hexagonal composition region, within which the Ca-Mg-Ni metallic glass formation is energetically favored, but also pinpoint an optimized sub-region within which the amorphization driving force, i.e. the energy difference between the solid solution and disordered phase, is larger than that outside. The simulations further reveal that the physical origin of glass formation is the solid solution collapsing when the solute atom exceeds the critical solid solubility. Further structural analysis indicates that the pentagonal bi-pyramids dominate in the optimized sub-region. The large atomic size difference between Ca, Mg and Ni extends the short-range landscape and facilitates the development of a hybridized packing model in the medium-range, and eventually enhancing the glass formation in the system. The predictions are well supported by the experimental observations reported so far, and could be of help for designing the ternary glass formation.

7.
Sci Rep ; 6: 29722, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27418115

RESUMO

Based on the newly constructed n-body potential of Ni-Ti-Mo system, Molecular Dynamics and Monte Carlo simulations predict an energetically favored glass formation region and an optimal composition sub-region with the highest glass-forming ability. In order to compare the producing techniques between liquid melt quenching (LMQ) and solid-state amorphization (SSA), inherent hierarchical structure and its effect on mechanical property were clarified via atomistic simulations. It is revealed that both producing techniques exhibit no pronounced differences in the local atomic structure and mechanical behavior, while the LMQ method makes a relatively more ordered structure and a higher intrinsic strength. Meanwhile, it is found that the dominant short-order clusters of Ni-Ti-Mo metallic glasses obtained by LMQ and SSA are similar. By analyzing the structural evolution upon uniaxial tensile deformation, it is concluded that the gradual collapse of the spatial structure network is intimately correlated to the mechanical response of metallic glasses and acts as a structural signature of the initiation and propagation of shear bands.

8.
Phys Chem Chem Phys ; 18(29): 19976, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27402030

RESUMO

Retraction of 'Atomic-scale simulation to study the dynamical properties and local structure of Cu-Zr and Ni-Zr metallic glass-forming alloys' by M. H. Yang et al., Phys. Chem. Chem. Phys., 2016, 18, 7169-7183.

9.
Genet Mol Res ; 15(1)2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26909911

RESUMO

The aim of the present study is to examine the expression level of peripheral mir-21 in multiple myeloma (MM) patients and to determine its clinical significance. MM patients (30), monoclonal gammopathy of undetermined significance (MGUS) patients (14), and normal controls (20) were recruited to determine the serum level of ß2-MG, IgA and IgM, IgG, λ, κ, TP, ALB, Hb, LDH, and Ca(2+). Gene expression of mir-21 was quantified by SYBR green real-time fluorescent quantitative PCR. We found that the expression level of serum mir-21 in the MM group was significantly higher than the MGUS group and the NC group (P < 0.01). According to the ISS installment, the level of mir-21, lgG, κ, and ALB in the MM group in stage I differed from that in stages II and III. The level of IgA, ß2-MG in stage III was higher as compared with stage I and II (P < 0.05 and P < 0.01).The levels of mir-21, κ, (κ+λ), IgG, (IgG + IgA + IgM), and ß2-MG in MM patients were positively correlated with ALB (P < 0.01). Based on the results, miR-21 plays an important role as an oncogene. Mir-21 may be important in the occurrence, development, and disease prognosis of MM.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Gamopatia Monoclonal de Significância Indeterminada/metabolismo , Mieloma Múltiplo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Feminino , Humanos , Imunoglobulinas/sangue , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/sangue , Gamopatia Monoclonal de Significância Indeterminada/genética , Mieloma Múltiplo/sangue , Mieloma Múltiplo/genética , Regulação para Cima
10.
Phys Chem Chem Phys ; 18(10): 7169-83, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26888279

RESUMO

Molecular dynamics simulation with well-developed EAM potentials was carried out to investigate the transport properties and local atomic structure of Cu-Zr and Ni-Zr metallic glasses and supercooled liquids. It is found that Cu or Ni atoms have much faster dynamics than Zr atoms in relaxation timescales, while Zr atoms display faster dynamics in the Cu-Zr system than in the Ni-Zr system. A dynamical crossover phenomenon from Arrhenius to super-Arrhenius behavior in the transport properties was observed for the Cu65Zr35 system at Tx ≈ 1250 K and the Ni65Zr35 system at Tx ≈ 1500 K, respectively. Further structural analysis suggests that the dominant interconnected clusters in Cu65Zr35 and Ni65Zr35 systems are 〈0, 0, 12, 0〉, 〈0, 1, 10, 2〉, 〈0, 2, 8, 2〉 and 〈0, 3, 6, 4〉. To directly characterize and visualize the correlated dynamics, we regard the full icosahedra as the microscopic origin responsible for the formation of metallic glasses in the Cu65Zr35 system, while the metallic glass formation in the Ni65Zr35 system can be attributed to the slow dynamics of 〈0, 3, 6, 4〉, 〈0, 2, 8, 2〉 and 〈0, 1, 10, 2〉 Ni-centered Voronoi polyhedra. The local atomic order and dynamics for Cu65Zr35 and Ni65Zr35 systems are remarkably different, and these differences are presumed to hinder crystal nucleation and growth, hence promoting the largely different bulk glass-forming ability.

11.
Sci Rep ; 5: 16218, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26592568

RESUMO

For a ternary alloy system promising for obtaining the so-called bulk metallic glasses (BMGs), the first priority issue is to predict the favored compositions, which could then serve as guidance for the appropriate alloy design. Taking the Al-Ni-Y system as an example, here we show an atomistic approach, which is developed based on a recently constructed and proven realistic interatomic potential of the system. Applying the Al-Ni-Y potential, series simulations not only clarify the glass formation mechanism, but also predict in the composition triangle, a hexagonal region, in which a disordered state, i.e., the glassy phase, is favored energetically. The predicted region is defined as glass formation region (GFR) for the ternary alloy system. Moreover, the approach is able to calculate an amorphization driving force (ADF) for each possible glassy alloy located within the GFR. The calculations predict an optimized sub-region nearby a stoichiometry of Al80Ni5Y15, implying that the Al-Ni-Y metallic glasses designed in the sub-region could be the most stable. Interestingly, the atomistic predictions are supported by experimental results observed in the Al-Ni-Y system. In addition, structural origin underlying the stability of the Al-Ni-Y metallic glasses is also discussed in terms of a hybrid packing mode in the medium-range scale.

12.
Genet Mol Res ; 14(4): 11791-805, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26436504

RESUMO

Studying the network of protein-protein interactions (PPIs) will provide valuable insights into the inner workings of cells. It is vitally important to develop an automated, high-throughput tool that efficiently predicts protein-protein interactions. This study proposes a new model for PPI prediction based on the concept of chaos game representation and the wavelet transform, which means that a considerable amount of sequence-order effects can be incorporated into a set of discrete numbers. The advantage of using chaos game representation and the wavelet transform to formulate the protein sequence is that it can more effectively reflect its overall sequence-order characteristics than the conventional correlation factors. Using such a formulation frame to represent the protein sequences means that the random forest algorithm can be used to conduct the prediction. The results for a large-scale independent test dataset show that the proposed model can achieve an excellent performance with an accuracy value of about 0.86 and a geometry mean value of about 0.85. The model is therefore a useful supplementary tool for PPI predictions. The predictor used in this article is freely available at http://www.jci-bioinfo.cn/PPI.


Assuntos
Proteínas de Bactérias/metabolismo , Modelos Estatísticos , Mapeamento de Interação de Proteínas/estatística & dados numéricos , Proteínas de Saccharomyces cerevisiae/metabolismo , Análise de Ondaletas , Biologia Computacional/métodos , Conjuntos de Dados como Assunto , Helicobacter pylori/metabolismo , Saccharomyces cerevisiae/metabolismo
13.
Phys Chem Chem Phys ; 17(22): 14879-89, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25981154

RESUMO

With the aid of ab initio calculations, a realistic interatomic potential was constructed for the Mg-Cu-Y ternary system under the proposed formalism of smoothed and long-range second-moment approximation of tight-binding. Taking the potential as the starting base, an atomistic computation/simulation route was developed for designing favored and optimized compositions for Mg-Cu-Y metallic glass formation. Simulations revealed that the physical origin of metallic glass formation is the collapse of crystalline lattice when solute concentration exceeds a critical value, thus leading to predict a hexagonal region in the Mg-Cu-Y composition triangle, within which metallic glass formation is energetically favored. It is proposed that the hexagonal region can be defined as the intrinsic glass formation region, or quantitative glass formation ability of the system. Inside the hexagonal region, the driving force for formation of each specific glassy alloy was further calculated and correlated with its forming ability in practice. Calculations pinpointed the optimized stoichiometry in the Mg-Cu-Y system to be Mg64Cu16Y20, at which the formation driving force reaches its maximum, suggesting that metallic glasses designed to have compositions around Mg64Cu16Y20 are most stable or easiest to obtain. The predictions derived directly from the atomistic simulations are supported by experimental observations reported so far in the literature. Furthermore, Honeycutt-Anderson analysis indicated that pentagonal bipyramids (although not aggregating to form icosahedra) dominate in the local structure of the Mg-Cu-Y metallic glasses. A microscopic picture of the medium-range packing can then be described as an extended network of the pentagonal bipyramids, entangled with the fourfold and sixfold disclination lines, jointly fulfilling the space of the metallic glasses.

14.
Phys Chem Chem Phys ; 17(20): 13355-65, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25923843

RESUMO

An interatomic potential was constructed for the Ni-Zr-Mo ternary metal system with the newly proposed long-range empirical formulism, which has been verified to be applicable for fcc, hcp and bcc transition metals and their alloys. Applying the constructed potential, molecular dynamics simulations predict a hexagonal composition region within which metallic glass formation is energetically favored. Based on the simulation results, the driving force for amorphous phase formation is derived, and thus an optimized composition is pinpointed to Ni45Zr40Mo15, of which the metallic glass could be most stable or easiest to obtain. Further structural analysis indicates that the dominant interconnected clusters for Ni64Zr36-xMox MGs are 〈0, 0, 12, 0〉, 〈0, 1, 10, 2〉, 〈0, 2, 8, 2〉 and 〈0, 3, 6, 4〉. In addition, it is found that the appropriate addition of Mo content could not only make a more ordered structure with a higher atomic packing density and a lower energy state, but also improve the glass formation ability of Ni-Zr-Mo alloys. Moreover, inherent hierarchical atomic configurations for ternary Ni-Zr-Mo metallic glasses are clarified via the short-range, medium-range and further in the extended scale of the icosahedral network.

15.
J Phys Chem B ; 119(8): 3608-18, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25646858

RESUMO

Recent progress in the synthesis of Mg-based metallic glasses (MGs) has allowed them to be considered as potential candidates for biodegradable and bioabsorbable implant materials. In this work, we use the Mg-Zn-Ca system as a representative to investigate the effect of composition on the atomic-level structure and local chemical environment in Mg-based MGs from ab initio molecular dynamics simulations. The results suggest that the short-range order of Mg(95-x)Zn(x)Ca5 (x = 21, 25, 29, and 33) MGs is characterized by Zn-centered icosahedral and icosahedral-like clusters, which show an increasing number and a rising tendency to interpenetrate each other with the enrichment of Zn constituents. A considerable degree of charge transfer between Zn and the surrounding Mg/Ca atoms is observed through electronic structure and bonding character analysis. At Zn-rich compositions, a percolated Zn-Zn network extended throughout the entire sample is formed, upon which the accumulated charges around Zn atoms are associated into a continuous conductivity path. Such results may shed light on the improved corrosion resistance of the Zn-rich Mg-Zn-Ca MGs.


Assuntos
Cálcio/química , Vidro/química , Magnésio/química , Zinco/química , Elétrons , Simulação de Dinâmica Molecular
16.
Phys Chem Chem Phys ; 16(36): 19590-601, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25110190

RESUMO

Inherent hierarchical structure and its effect on shear localization were clarified for ternary Mg-Cu-Ni metallic glasses via molecular dynamics studies based on a newly constructed n-body potential for the system. Assisted by a proposed index to detect the medium-range correlation heterogeneity, it was found that the Cu/Ni-centered icosahedra and specific Mg-centered clusters exhibit a strong preference to interconnect, leading to the formation, over an extended scale, of a percolated network that serves as structural skeleton in the glassy matrix. In constituting the skeleton network, the clusters mainly integrate in an interpenetrating mode, while the noninterpenetrating linkages provide additional reinforcements, jointly consolidating the structural and energetic stability of the skeleton. Furthermore, by monitoring the structural evolution upon compressive deformation, it was revealed that the gradual collapse of the skeleton network is intimately correlated to the mechanical response of metallic glasses and acts as a structural signature of the initiation and propagation of shear bands.

17.
J Phys Chem B ; 118(16): 4442-9, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24735222

RESUMO

A realistic interatomic potential is constructed for the Al-Cu-Y system under a newly proposed formulism and applied to perform atomistic simulations, leading to predicting a hexagonal composition region within which metallic glass formation is energetically favored and the region is defined as the quantitative glass formation ability of the system. Amorphization driving force of a glassy alloy is then calculated to correlate the readiness of its forming ability in practice, and a local optimized stoichiometry is pinpointed to be Al74Cu14Y12, of which the metallic glass could be most stable or easiest obtainable. The predictions are well supported by the experimental observations reported so far in the literature. Further structural analysis indicates that adding Y extends the short-range landscape and facilitates developing a hybridized icosahedral- and fcc-like packing in the medium-range, eventually enhancing the glass formation ability of the system.

18.
J Phys Condens Matter ; 25(9): 095005, 2013 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-23334440

RESUMO

Based on the recently constructed Ni-Zr-Al n-body potential, Monte Carlo simulations are performed to study the glass formation and associated structural evolutions in the system. The micro-chemical inhomogeneity (MCI) parameter and Honeycutt and Anderson (HA) pair analysis are employed to investigate both the chemical short-range orders and topological short-range orders for the ternary Ni-Zr-Al metallic glasses. Results reveal that remarkable chemical short-range orders (CSROs) exist in the ternary Ni-Zr-Al metallic glasses and are strongly influenced by the chemical interactions among the constituent elements. Moreover, topological short-range orders are clearly formed in the ternary Ni-Zr-Al metallic glasses, with the most remarkable characteristic being the icosahedral local packing. Similarly to CSRO, the extent of icosahedral short-range orders formed in the Ni-Zr-Al system varies distinctly with the chemical composition. In addition, simulation results reveal that chemical short-range orders and topological short-range orders turn out to be influenced by different factors. Unlike CSRO, both chemical interactions and geometrical constraints play important roles in forming the topological short-range orders.

19.
Phys Chem Chem Phys ; 14(23): 8290-3, 2012 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-22573179

RESUMO

Based on the constructed Cu-Hf interatomic potential, Monte Carlo simulations were conducted to reveal the atomic configurations in heating and quenching of a CuHf(2) alloy through scrutinizing the evolution of microchemical inhomogeneity. Simulations show that the CuHf(2) crystalline structure becomes more homogeneous during heating but an obvious drop in microchemical inhomogeneity appears when reaching its melting point. During the quenching process, the CuHf(2) melt becomes increasingly inhomogeneous and shows a change in the slope in the microchemical inhomogeneity around glass transition temperature. Simulation results were evidenced by the atomic packing analysis through the Voronoi tessellation method. The implications of our study suggest that the glass transition could be visualized as a process involving increase of microchemical inhomogeneity from the liquid to glassy state.

20.
J Phys Chem B ; 115(16): 4703-8, 2011 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-21473611

RESUMO

For the Cu-Zr-Ni system, an interatomic potential was constructed under the newly proposed formulism named smoothed and long-range second-moment approximation of tight-binding. Applying the constructed potential, molecular dynamics simulations were carried out to compare the relative stability of crystalline solid solution versus its disordered counterpart. Simulations not only reveal that the origin of metallic glass formation is the crystalline lattice collapsing while the solute concentrations exceed critical values, but also determine a quadrilateral region, within which the metallic glass formation is energetically favored. Moreover, the energy differences between the crystalline solid solutions and the disordered states were considered as the driving force for amorphization and were computed by molecular static calculations. The calculation results located an optimized composition area with the driving force much greater than those outside. In addition, the alloys around the composition of Cu(16)Zr(60)Ni(24) were identified to have maximum driving force, and the atomic configurations were also analyzed by the Voronoi tessellation method.

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