Key Laboratory of Biorheological Science and Technology

Laboratory of, China

Key Laboratory of Biorheological Science and Technology

Laboratory of, China
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Huang M.,Chongqing University | Huang M.,Chongqing Technology and Business University | Wang Y.,Key Laboratory of Biorheological Science and Technology | Luo Y.,Chongqing Technology and Business University | Pan F.,Chongqing University
Asian Journal of Chemistry | Year: 2013

A novel shape memory porous scaffold was prepared by copolymerization and emulsion copolymerization method. Initially, isocyanate I terminated prepolymer was prepared from reaction of HO-terminated poly (lactide-co-p-dioxanone) with hexamethylene diisocyanate for 3 h at 70∼75 °C. Then the excess NCO reacted with butanediamine below 5 °C, aiming to realize chain extension. During this process, the porogen NaCl/PVP was introduced. The emulsion was dried by vacuum and the dried materials were compressed to special shape and then salt leaching method was used to prepare porous scaffold. The pore structure and pore size were characterized by scanning electron microscopy and the porosity was measured with liquid substitution method and connectivity was measured by calculating the ratio of drip mass to time. Mechanical performance and shape memory property were also studied. These results denoted that pore size and porosity have significant influence on the mechanical and shape memory properties of shape memory poly(urethane-urea). However, the shape memory property is as high as 52 % ∼ 80 % and mechanical modulus is 100-350 MPa, similar to the natural bone, which is beneficial to treatment of the non-union.


Shi L.T.,Xi'an Jiaotong University | Fang L.,Xi'an Jiaotong University | Wu F.,Xi'an Jiaotong University | Liao X.L.,Key Laboratory of Biorheological Science and Technology | Meng F.M.,Xi'an Jiaotong University
Materials and Corrosion | Year: 2016

Ternary Ni-Co-P/TiN (20nm) nanocomposite coatings with Co content in the range of 0-23wt% were successfully co-deposited on Al alloys by electroless plating. The morphology, composition, microstructure, micro-hardness, wear behavior, and corrosion properties of the coatings were tested using SEM, EDS, XRD, Vickers hardness, ball-on-disc wear tester, and electrochemical workstation, respectively. The effect of Co content on the tribological and corrosion properties of Ni-Co-P/TiN coatings was studied. It is found that all the coatings have a compact and rough granular structure with sub-micro globules non-uniformly distributed on the surface. The grain size and the content of Ni and P decrease, but the micro-hardness, adhesion force, friction coefficient, and corrosion resistance correspondingly enhance with the increase of Co content in Ni-Co-P/TiN coatings. The improved corrosion resistance of Ni-Co-P/TiN coating is due to the passivation behavior and small grain caused by the introduction of Co. Based on the excellent properties on the wear and corrosion resistance, ternary Ni-Co23-P/TiN coating with high Co content, may be applied as an optimum protective coating for Al alloys. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yang D.D.,Chongqing University | Hou W.S.,Key Laboratory of Biorheological Science and Technology | Wu X.Y.,Chongqing University | Zheng X.L.,Chongqing University | And 2 more authors.
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS | Year: 2011

Multitendoned extrinsic muscles of the human hand can be divided into several neuromuscular compartments (NMCs), each of which contributes to the ability of human finger to produce independent finger movements or force. The aim of this study was to investigate the changes in the spatial activation of flexor digitorum superficialis (FDS) during the fingertip force production with non-invasive multichannel surface electromyography (sEMG) technique. 7 healthy Subjects were instructed to match the target force level for 5s using individual index finger (I), individual middle finger (M) and the combination of the index and middle finger (IM) respectively. Simultaneously, a 2×6 electrode array was employed to record multichannel sEMG from FDS as finger force was produced. The entropy and center of gravity of the sEMG root mean square (RMS) map were computed to assess the spatial inhomogeneity in muscle activation and the change in spatial distribution of EMG amplitude related to the force generation of specific task finger. The results showed that the area and intensity of high amplitude region increased with force production, and the entropy increased with force level under the same task finger. The findings indicate that the change of spatial distribution of multitendoned extrinsic hand muscle activation is correlated to specific biomechanical functions. © 2011 IEEE.


Tan W.,Key Laboratory of Biorheological Science and Technology | Tan W.,Chongqing University | Mei H.,Key Laboratory of Biorheological Science and Technology | Mei H.,Chongqing University | And 6 more authors.
Journal of Computer-Aided Molecular Design | Year: 2013

P-glycoprotein (P-gp) is an ATP-binding cassette multidrug transporter. The over expression of P-gp leads to the development of multidrug resistance (MDR), which is a major obstacle to effective treatment of cancer. Thus, designing effective P-gp inhibitors has an extremely important role in the overcoming MDR. In this paper, both ligand-based quantitative structure-activity relationship (QSAR) and receptor-based molecular docking are used to predict P-gp inhibitors. The results show that each method achieves good prediction performance. According to the results of tenfold cross-validation, an optimal linear SVM model with only three descriptors is established on 857 training samples, of which the overall accuracy (Acc), sensitivity, specificity, and Matthews correlation coefficient are 0.840, 0.873, 0.813, and 0.683, respectively. The SVM model is further validated by 418 test samples with the overall Acc of 0.868. Based on a homology model of human P-gp established, Surflex-dock is also performed to give binding free energy-based evaluations with the overall accuracies of 0.823 for the test set. Furthermore, a consensus evaluation is also performed by using these two methods. Both QSAR and molecular docking studies indicate that molecular volume, hydrophobicity and aromaticity are three dominant factors influencing the inhibitory activities. © 2013 Springer Science+Business Media Dordrecht.


Xie J.,Key Laboratory of Dependence Service Computing in Cyber Physical Society | Xie J.,Chongqing University | Xu Z.,Key Laboratory of Biorheological Science and Technology | Xu Z.,Chongqing University | And 10 more authors.
PLoS ONE | Year: 2013

Prediction of proteasomal cleavage sites has been a focus of computational biology. Up to date, the predictive methods are mostly based on nonlinear classifiers and variables with little physicochemical meanings. In this paper, the physicochemical properties of 14 residues both upstream and downstream of a cleavage site are characterized by VHSE (principal component score vector of hydrophobic, steric, and electronic properties) descriptors. Then, the resulting VHSE descriptors are employed to construct prediction models by support vector machine (SVM). For both in vivo and in vitro datasets, the performance of VHSE-based method is comparatively better than that of the well-known PAProC, MAPPP, and NetChop methods. The results reveal that the hydrophobic property of 10 residues both upstream and downstream of the cleavage site is a dominant factor affecting in vivo and in vitro cleavage specificities, followed by residue's electronic and steric properties. Furthermore, the difference in hydrophobic potential between residues flanking the cleavage site is proposed to favor substrate cleavages. Overall, the interpretable VHSE-based method provides a preferable way to predict proteasomal cleavage sites. © 2013 Xie et al.


Yang W.,Key Laboratory of Biorheological Science and Technology | Yang W.,Chongqing University | Fang J.,Key Laboratory of Biorheological Science and Technology | Fang J.,Chongqing University | And 5 more authors.
Molecular Physics | Year: 2011

In this study, the theoretical structures of armchair (6, 6) and zigzag (12, 0) TiOO2 nanotubes (TiNTs) were constructed by rolling the (101) layer of an anatase TiO2 crystal. The (101) layer was made using Materials Studio (MS) by cutting the cleave plane (101) of the anatase TiO2 crystal. Based on these structures, the basic properties of TiO2 nanotubes were investigated using MS. Molecular dynamics simulations were performed using the software NAMD to investigate the status and permeation of water through the TiO2 nanotubes. Structure analysis shows that both the inner and outer walls of the structures were terminated with oxygen atoms. The thicknesses of single tube walls are smaller than that of a perfect triple layer (2.20 Å) in bulk anatase TiO2. With regard to the bulk Ti-O bond length, the Ti-O bonds in the outer layer are elongated, and are shortened in the inner layer. Molecular dynamics simulation shows that the water molecules in the nanotubes move back and forth, as in one-dimensional Brownian motion. Moreover, the penetration properties of TiNTs are associated with their radii, with the TiNT with larger radii having better penetration properties. Thus, when used in drug delivery or filtration systems, armchair TiNT has a better effect than zigzag TiNT. © 2011 Taylor & Francis.


Chao L.,Chongqing University | Chao L.,Key Laboratory of Biorheological Science and Technology | Mei H.,Chongqing University | Mei H.,Key Laboratory of Biorheological Science and Technology | And 5 more authors.
Chemometrics and Intelligent Laboratory Systems | Year: 2014

The human cytochrome P450 (CYP450) superfamily plays an important role in drug-drug interactions, drug metabolism, and toxicity. Therefore, prediction of CYP450 inhibitors is extremely important in drug discovery and personal medicine. In this paper, characterized by fragment-based molecular hologram and MACCS descriptors, over 12,000 unique compounds with known CYP2C19 inhibitory activities were used to develop prediction models by partial least squares discriminant analysis (PLSDA) and support vector machine (SVM) methods. By combining two types of fragment-based descriptors, an optimal SVM model with an RBF kernel was obtained. The sensitivity, specificity, accuracy, and Matthews correlation coefficient (MCC) were 86.54%, 83.39%, 84.76%, and 0.6946 for a training set (. n=. 5,387), and 83.19%, 78.82%, 80.72%, and 0.6152 for a test set (. n=. 5,383), respectively. The optimal SVM model was further validated by an independent dataset (. n=. 1,470) with an overall accuracy of 82.38%. The results showed that these two types of fragment-based descriptors are, in some degree, complementary to each other, and can be combined to enhance model predictive power. In comparison with other 2-D or 3-D description methods, the combination of fragment descriptors seems extremely useful in constructing high-throughput screening models of CYP inhibitors in the process of drug discovery. © 2013 Elsevier B.V.


Sun J.,Chongqing University | Sun J.,Key Laboratory of biorheological science and technology | Cai S.,Chongqing University | Cai S.,Key Laboratory of biorheological science and technology | And 3 more authors.
European Journal of Medicinal Chemistry | Year: 2010

Surflex-Dock is employed to investigate interactions between neuraminidase inhibitors (NIs) and neuraminidase (NA), which illuminate that carboxyl group, amino (guanidino) group, amide group, hydroxy group are crucial. Hydrogen bonds and hydrophobic interactions impact on activities of NIs. There is a strong correlation between binding affinity and pIC50, with r = 0.813. We have developed three-dimensional holographic vector of atomic interaction field analysis (HoVAIFA) as a new method of 3D-QSAR to understand chemical-biological interactions. Good results, R2 = 0.789 and R2cv = 0.732, show that HoVAIFA can be applicable to molecular structural characterization and bioactivity prediction. Electrostatic, steric and hydrophobic interactions affect activities of NIs. HoVAIFA and docking results are corresponding, which illustrates that HoVAIFA is an effective methodology for characterization of complex interactions of drug molecules. Crown Copyright © 2009.


Zou H.,Key Laboratory of Biorheological Science and Technology | Huang J.,Key Laboratory of Biorheological Science and Technology | Fang F.,Chongqing University | Guo J.,Chongqing University
Advanced Materials Research | Year: 2011

In this research the genes (amoA and hao) for ammonia monooxygenase (AMO) and hydroxylamine oxidoreductase (HAO) responsible for ammonia oxidation reaction in completely autotrophic nitrogen removal over nitrite process were cloned and sequenced, and the recombinant protein of AMO and HAO was expressed and characterized. The optimum temperature for AMO activity was 55 °C and more than 40% of the maximum activity was retained from 15-50 °C. The optimum pH for the enzyme was found to be pH 11.0. The highest activity for HAO was observed at 45 °C. More than 50% of the maximum activity was retained even at 55 °C. The dependence of HAO on pH was strong and only average 15% of residual activity left at pH ranging from 3.0-9.0. Study on the molecular and biochemistry properties of recombinant AMO and HAO will benefit for the manipulation of ammonia-oxidizing bacteria to achieve the goal of high efficiency of nitrogen removal. © (2011) Trans Tech Publications.


PubMed | Key Laboratory of Biorheological Science and Technology
Type: Journal Article | Journal: Journal of computer-aided molecular design | Year: 2014

P-glycoprotein (P-gp) is an ATP-binding cassette multidrug transporter. The over expression of P-gp leads to the development of multidrug resistance (MDR), which is a major obstacle to effective treatment of cancer. Thus, designing effective P-gp inhibitors has an extremely important role in the overcoming MDR. In this paper, both ligand-based quantitative structure-activity relationship (QSAR) and receptor-based molecular docking are used to predict P-gp inhibitors. The results show that each method achieves good prediction performance. According to the results of tenfold cross-validation, an optimal linear SVM model with only three descriptors is established on 857 training samples, of which the overall accuracy (Acc), sensitivity, specificity, and Matthews correlation coefficient are 0.840, 0.873, 0.813, and 0.683, respectively. The SVM model is further validated by 418 test samples with the overall Acc of 0.868. Based on a homology model of human P-gp established, Surflex-dock is also performed to give binding free energy-based evaluations with the overall accuracies of 0.823 for the test set. Furthermore, a consensus evaluation is also performed by using these two methods. Both QSAR and molecular docking studies indicate that molecular volume, hydrophobicity and aromaticity are three dominant factors influencing the inhibitory activities.

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