Bio-Medical Materials and Engineering - Volume 26, issue s1

Authors: Wang, Baiyan | Han, Qianqian | Zhu, Yanqin

Article Type: Research Article

Abstract: To investigate the inhibition effect of oxymatrine induces human lung cancer A549 cells apoptosis. The A549 cells were cultured for 24 h, than the various concentration of oxymatrine (2 mmol/L, 4 mmol/L, 8 mmol/L, 15 mmol/L) were added into different experimental group cells, and 5-fluorouracil were added into the positive control group cells for 12 h, 24 h, 36 h, 48 h respectively. The A549 cells inhibition rate, apoptosis, and the expression of Bcl-2 and Bax were examined by MTT method, Annexin V/PI double staining method, real-time quantitative PCR and western blot, respectively. At same time, the morphological changes of …A549 cells were observed with an inverted microscope. In the range of 2 mmol/L~15 mmol/L, oxymatrine had obvious inhibition effects on the proliferation of A549 cells. Compared with the negative control group, it has significantly different (P <0.01). There was remarkably the time- and dose-dependent correlation. After A549 cells were treated with 8 mmol/L oxymatrine for 24 h, the morphological change of cell apoptosis was observed and the extent of apoptosis was quantified by flow cytometry. Furthermore, the expression of Bcl-2 was reduced and the expression of Bax was increased remarkably (P <0.05). Oxymatrine has significant inhibition effects on the cells proliferation and the effects showed time-dependent and dose-dependent. Oxymatrine can induce apoptosis of the A549 cells by regulating the expression of Bcl-2 and Bax. Show more

Keywords: Oxymatrine, A549 cells, proliferation inhibition, apoptosis, Bcl-2, Bax

DOI: 10.3233/BME-151302

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S165-S172, 2015

Authors: Chiang, Ming-Che | Huang, Ching-Cheng

Article Type: Research Article

Abstract: A novel technique and product for carpal tunnel microscopic surgical procedures using a modified medical device containing a head as a surgical scalpel under light guidance were designed and studied. The novel design of the medical device was developed and applied in a new carpal tunnel microscopic surgical procedure in place of the traditional carpal tunnel surgical procedure. Biological and clinical evaluations of carpal tunnel surgical procedure using the designed optically guided medical device were studied. For commercialized reasons, some guidance was considered, such as ISO 10993-1:2009(E), for the biological evaluation of the device. Furthermore, a clinical evaluation was carried …out. The designed optically guided medical device could provide a powerful medical device for carpal tunnel syndrome and related applications. Show more

Keywords: Biological evaluation, clinical evaluation, carpal tunnel, microscopic surgical procedure, scalpel

DOI: 10.3233/BME-151303

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S173-S179, 2015

Authors: Li, Xiaoda | Zhang, Xiangkui | Hu, Ping | Liu, Weijie | Shen, Guozhe | Zhan, Xianghui

Article Type: Research Article

Abstract: The locking compression plate fixation treatment for the unstable sacral fractures is simple and effective, with less trauma and complications. Some locking compression plate parts have been made of high-strength Plate manufactured by hot stamping process since the demand for lightweight biomedical materials. Finite Element (FE) method of One-Step inverse forming based on deformation theory is the tool to evaluate the formability of locking compression plate panel quickly in initial design for reducing costs and development cycle of Plate. But current one-step inverse forming methods are all suitable for cold stamping, not hot-stamping. This paper proposed one-step inverse forming method …and workflow for hot-stamping of locking compression Plate. And the B pillar of a sacral bone was simulated and its computing result was compared with experimental value. The result shows that the proposed method in this paper can quickly evaluate high temperature formability of high-strength Plate. And the method is proposed to be used in initial design. Show more

Keywords: Sacral fractures, finite element, locking compression plate, one-step inverse forming, high-strength

DOI: 10.3233/BME-151304

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S181-S188, 2015

Authors: Su, Wen-Ta | Shih, Yi-An

Article Type: Research Article

Abstract: The nervous system is an important regulator of the human body because it adapts our responses to the external environment and provides people the ability of thought, memory, and emotion. PC12 is a cell line that is commonly used to study the behavior of neural differentiation. PC12 cells further differentiate into nerve cells when stimulated by nerve growth factor (NGF), which have neurite, dendrite, and axon, and form synapses with neighboring cells to build neural networks. Micropatterns and electric stimulation can significantly influence cellular attachment, proliferation, orientation, extracellular matrix (ECM) expression, neural differentiation, and cellular motion. We fabricated polycaprolactone (PCL) …nanofiber with or without carbon nanotubes (CNTs) by electrospinning and promoted the neural differentiation of PC12 cells by electric stimulation. We used scanning electron microscope (SEM) and fluorescence microscope to observe the NGF-induced growth of PC12 cells on PCL nanofiber. Axon formation and cellular activity expression, that confirm that PC12 cells can grow well on PCL nanofiber, and the gene expressions of MAP1b and GAP43 significantly increased after electric stimulation. Based on the results, the structure of nanofibers containing CNTs can effectively induce neural differentiation of PC12 cells in an electric field. This experimental model can be used for future clinical applications. Show more

Keywords: PC12 cells, carbon nanotube, electric stimulation, neuritogenesis

DOI: 10.3233/BME-151305

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S189-S195, 2015

Authors: Huang, Jianghong | Xiong, Jianyi | Liu, Jianquan | Zhu, Weimin | Chen, Jielin | Duan, Li | Zhang, Jufeng | Wang, Daping

Article Type: Research Article

Abstract: To determine the optimal ratio of nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) in the novel three-dimensional porous PLLA/n-HA composite scaffolds, low-temperature rapid prototyping technology was employed to fabricate the composite materials with different n-HA contents. Mechanical properties and degradation behaviors of the composites were examined, and the scaffold microstructure and n-HA dispersion were observed by scanning electron microscope (SEM). Mechanical tests demonstrated that the tensile strength of the composite material gradually decreased with an increase in n-HA content. When the n-HA content reached 20 wt%, the bending strength of the composite material peaked at 138.5 MPa. SEM images demonstrated that …the optimal content of n-HA was 20 wt% as the largest interconnected pore size that can be seen, with a porosity as high as 80%. In vitro degradation experiments demonstrated that the pH value of the material containing solution gradually decreased in a time-dependent manner, with a simultaneous weakening of the mechanical properties. In vitro study using rat osteoblast cells showed that the composite scaffolds were biocompatible; the 20 wt% n-HA scaffold offered particular improvement to rat osteoblast cell adhesion and proliferation compared to other compositions. It was therefore concluded that 20 wt% n-HA is the optimal nano-hydroxyapatite (n-HA) to polylactic acid (PLLA) ratio, with promise for bone tissue engineering. Show more

Keywords: Three-dimensional porous, polylactic acid, nano-hydroxyapatite, rapid prototyping

DOI: 10.3233/BME-151306

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S197-S205, 2015

Authors: Omar, Nadzeri | Zhong, Yongmin | Jazar, Reza N. | Subic, Aleksandar | Smith, Julian | Shirinzadeh, Bijan

Article Type: Research Article

Abstract: This paper presents a new method for real-time modelling soft tissue deformation. It improves the traditional mass-spring model with conical springs to deal with nonlinear mechanical behaviours of soft tissues. A conical spring model is developed to predict soft tissue deformation with reference to deformation patterns. The model parameters are formulated according to tissue deformation patterns and the nonlinear behaviours of soft tissues are modelled with the stiffness variation of conical spring. Experimental results show that the proposed method can describe different tissue deformation patterns using one single equation and also exhibit the typical mechanical behaviours of soft tissues.

Keywords: Soft tissue modelling, tissue deformation patterns, stiffness variation, conical spring

DOI: 10.3233/BME-151307

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S207-S214, 2015

Authors: Kim, Hyoung-Ho | Choi, Young Ho | Lee, Seung Bae | Baba, Yasutaka | Kim, Kyung-Wuk | Suh, Sang-Ho

Article Type: Research Article

Abstract: A ureteral stenosis or occlusion causes the disturbance of normal urine flow and results in renal failure. Ureteral stents are used to relieve the stagnation of urine in the upper urinary tract. Peristalsis in the ureter, which occurs to help urine flow, becomes to weaken when a stent is inserted and effective peristalsis disappears as time goes on, and a stented ureter seems to be tubular and curved in the human body. Double J stents, which are manufactured by many medical companies and are used widely these days, have different geometries of side holes in the stent shafts. In total, …12 models—six curved models of a stented ureter according to different numbers and positions of side holes and ureteral and stent stenoses and another six straight models for comparison with the curved ones—were made based on the data collected from 19 men. The flow rate and pattern in the stented ureter were evaluated using computational fluid dynamics (CFD). According to the results, curved models reflecting the human anatomy seem to be more desirable in the CFD simulation of urine flow and must be good for evaluating the effect of geometrical variations in stent design on urine flow. Show more

Keywords: Ureter, stent, flow, CFD, numerical analysis

DOI: 10.3233/BME-151308

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S215-S223, 2015

Authors: Wang, Shengzhang | Li, Jianjun | Wang, Chao | Yang, Xinjian | Mu, Shiqing | Wang, Wuqing

Article Type: Research Article

Abstract: Flow diverter is a kind of stent-like devices with higher metal coverage rate, and it is deployed endovascularly to treat cerebral aneurysms, especially to treat giant aneurysms. However, there exist some arguments about its safety and efficacy. Hemodynamics is considered to play very important role during the initiation, growth and rupture of cerebral aneurysms. In this study, the models of a giant cerebral aneurysm involved a small branch at the aneurysmal sac before and after flow diverter implantation were constructed by virtual deployment, the blood flows in the models were simulated by computational fluid dynamics method. Analyzing the variations of …the hemodynamics, the following conclusions were summarized. The flow diverter is very effective device to occlude the aneurysm, the flow rate at the small branch was rarely changed when the flow diverter deployed and the flow diverter. Show more

Keywords: Cerebral aneurysm, hemodynamics, flow diverter, virtual deployment, numerical simulation

DOI: 10.3233/BME-151309

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S225-S231, 2015

Authors: Li, X. | Wang, X.K. | Chen, B. | Pu, Y.S. | Li, Z.F. | Nie, P. | Su, K.

Article Type: Research Article

Abstract: Portal vein hypertension generally occurs in liver diseases like hepatic cirrhosis. It causes hemodynamic changes that are closely related to liver disease. At advanced stages of hepatic cirrhosis, portal vein hypertension leads to the atrophy of the right lobe of the liver and the hypertrophy of the left lobe through a process that has not yet been fully explained. Based on the hemodynamic changes that are known to occur, we hypothesize that liver volume is related to the distribution of blood flowing from the splenic vein (SV) that carries hepatotrophic factors from the spleen and pancreas. We studied blood flow …in the portal vein system to validate this hypothesis through in vitro experimentation and a computational fluid dynamics (CFD) analysis involving both simplified and patient-specific models based on four healthy subjects and two patients with liver cirrhosis. The results confirmed the hypothesis that right-lobe atrophy is significantly influenced by the distribution of blood from the SV. Moreover, the patients with liver cirrhosis had a significantly larger mass fraction of spleen-derived blood in the left portal vein branch (LPV) than healthy subjects, a result consistent with right-lobe atrophy and left-lobe hypertrophy. Show more

Keywords: Portal vein hypertension, hemodynamics, hepatotrophic factor, splenic vein

DOI: 10.3233/BME-151310

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S233-S243, 2015

Authors: Cong, Yingbo | Wang, Liya | Liu, Xiao

Article Type: Research Article

Abstract: Three numerical models of an abdominal aortic aneurysm (AAA) with different geometric parameters are established in order to examine the coupled effect of the fluid-structure of AAA. The study is focused on examining the roles of the dilatation parameter and the aspect ratio of an AAA in the flow dynamic within a pulse period. The numerical results demonstrate that the vortex dominates the dynamic flow behavior within an AAA. During a pressure impulse cycle, an AAA is influenced by the entirety of the vortex, from its generation to its subsequent disappearance. As an indirect effect of the vortex dynamic acting …on vessels, a series of alternate impulse responses of the wall shear stress (WSS) is generated in an AAA as eddies induced by the vortex move along the axis of the vessels, and the strength of the responses is proportional to the strength of the eddies. The alternated impulse of WSS may be one of the main influencing factors on AAA rupture. The results of this study aided in understanding the mechanisms underlying the evolutionary processes of AAAs. Show more

Keywords: Abdominal aortic aneurysm, fluid-structure interaction, numerical analysis, geometric parameters, vortex dynamic, wall shear stress

DOI: 10.3233/BME-151311

Citation: Bio-Medical Materials and Engineering, vol. 26, no. s1, pp. S245-S255, 2015