bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of surface roughness on the initial response of MC3T3-E1 cells cultured on polished titanium alloy
Authors: Wu Chunya , Chen Mingjun , Zheng Ting , Yang Xiaonan 
Published: August 2015

Abstract Surface roughness has been considered as an important influencing factor for cell response. The aim of this study was to find out whether MC3T3-E1 cells, a mouse osteoblast-like cell line, can sense the amplitudes of surface topography of titanium alloy (Ti6Al4V), and if surface-dependent cell morphology would be presented on the substrata with varied roughness. A series of polished samples (Ra: 0.30∼1.80 μm) were prepared to produce macroscopically parallel grooves using different grades of silicon carbide sandpaper (#100, #320, #600, #1000 and #2000). The experimental results indicated that the behavior and morphology of cells largely depended on the substrata where they were cultured. More efficient proliferation of MC3T3-E1 cells was shown on the surfaces with Ra of 0.50∼1.00 μm, with respect to either the rougher or the smoother specimens. Furthermore, MC3T3-E1 cells seeded on the Ti6Al4V surfaces within this narrow range responded to the increasing surface roughness with increased proliferation. Contact guidance of cells could be observed on the rougher specimens (Ra: 0.80∼1.00 μm), whereas more random orientations were exhibited for the adsorbed cells on the smoother surfaces (Ra: 0.50∼0.60 μm).
Oxymatrine inhibited cell proliferation by inducing apoptosis in human lung cancer A549 cells
Authors: Wang Baiyan , Han Qianqian , Zhu Yanqin 
Published: August 2015

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.
Optically-guided scalpel with light-scattering module for carpal tunnel surgical procedure via minimally invasive surgery
Authors: Chiang Ming-Che , Huang Ching-Cheng 
Published: August 2015

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.
Nanofiber containing carbon nanotubes enhanced PC12 cell proliferation and neuritogenesis by electrical stimulation
Authors: Su Wen-Ta , Shih Yi-An 
Published: August 2015

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.
Numerical analysis of the urine flow in a stented ureter with no peristalsis
Authors: Kim Hyoung-Ho , Choi Young Ho , Lee Seung Bae , Baba Yasutaka , Kim Kyung-Wuk , Suh Sang-Ho 
Published: August 2015

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.
Hemodynamics investigation for a giant aneurysm treated by a flow diverter implantation
Authors: Wang Shengzhang , Li Jianjun , Wang Chao , Yang Xinjian , Mu Shiqing , Wang Wuqing 
Published: August 2015

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.
Computational hemodynamics of portal vein hypertension in hepatic cirrhosis patients
Authors: Li X. , Wang X.K. , Chen B. , Pu Y.S. , Li Z.F. , Nie P. , Su K. 
Published: August 2015

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.
A numerical study of fluid-structure coupled effect of abdominal aortic aneurysm
Authors: Cong Yingbo , Wang Liya , Liu Xiao 
Published: August 2015

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.
4D model of hemodynamics in the abdominal aorta
Authors: Zbicinski Ireneusz , Veshkina Natalia , Stefańczyk Ludomir 
Published: August 2015

Abstract The paper presents an application of the FSI technique to determine hemodynamics in the abdominal aorta (AA). To establish boundary conditions for the FSI study, MR anatomical data and 4D MRI velocity-mapping data (in three blood flow velocity directions and time) were collected to acquire realistic geometry of the AA and blood velocity. The mechanical parameters of the patient-specific aortic wall were applied in FSI simulations to describe wall mechanics and blood flow in the AA. Comparison of calculated and measured blood flow patterns and flow rate waveforms shows good agreement, which proves that wall pulsations should be incorporated into simulations that determine hemodynamics in the AA. The results of this work suggest that FSI analysis based on patient-specific data, such as the mechanical parameters of the aortic wall, real geometry of the aorta, and 4D flow information, might be used to predict the development of cardiovascular diseases.
Numerical study of the effect of blood vessel on the microwave ablation shape
Authors: Nie Xiaohui , Nan Qun , Guo Xuemei , Tian Zhen 
Published: August 2015

Abstract The existence of large blood vessels seriously impacts the results of microwave ablation on heat transfer of surrounding tissue, and the research of influences about large blood vessels could be essential and significant. The temperature distribution in the tissue was analyzed with a microwave heating source by finite element method. The model, where the blood vessel is parallel to antenna, has different distances from antenna to blood vessel. As distance was greater than 20mm, the effect of blood vessel that was parallel to antenna was ignored and the ablation area was elliptical-like. When distance was less than 10mm, the part of asymmetrical coagulated area was on the right side of blood vessel. Therefore, the temperature contour by different conditions could provide numerical references, which is whether to block blood vessel or not, to achieve the aim of guiding the clinical practice, according to the locations of tumor and blood vessel.
Numerical simulation of RF catheter ablation for the treatment of arterial aneurysm
Authors: Guo Xuemei , Nan Qun , Qiao Aike 
Published: August 2015

Abstract Considering the blood coagulation induced by the heating of radio frequency ablation (RFA) and the mechanism of aneurysm embolization, we proposed that RFA may be used to treat arterial aneurysm. But the safety of this method should be investigated. A finite element method (FEM) was used to simulate temperature and pressure distribution in aneurysm with different electrode position, electric field intensity and ablation time. When the electrode is in the middle of the artery aneurysm sac, temperature rose clearly in half side of artery aneurysm, which is not suitable for RFA. Temperature rose in the whole aneurysm when the electrode is under the artery aneurysm orifice, which is suitable for the ablation therapy. And in this way, the highest temperature was 69.585°C when power was 5.0 V/mm with 60 s. It can promote the coagulation and thrombosis generation in the aneurysm sac while the outside tissue temperature rises a little. Meanwhile, the pressure (10 Pa) at the top of aneurysm sac with electrode insertion is less than that (60 Pa) without electrode, so electrode implant may protect the aneurysm from rupture. The results can provide a theoretical basis for interventional treatment of aneurysm with RFA.
The exterior unsteady viscous flow and heat transfer due to a porous expanding or contracting cylinder
Authors: Wang Chao , Si Xinhui , Shen Yanan , Zheng Liancun , Lin Ping 
Published: August 2015

Abstract Since the vessels in the biological tissues are characterized by low seepage Reynolds numbers and contracting or expanding walls, more attention is paid on the viscous flow outside the porous pipe with small expansion or contraction. This paper presents a numerical solution of the flow and heat transfer outside an expanding or contracting porous cylinder. The coupled nonlinear similarity equations are solved by Bvp4c, which is a collocation method with MATLAB. The effects of the different physical parameters, namely the permeability Reynolds number,the expansion ratio and the Prandtl number, on the velocity and temperature distribution are obtained and the results are shown graphically.
A method to determine the mechanical properties of the retina based on an experiment in vivo
Authors: Qian Xiuqing , Zhang Kunya , Liu Zhicheng 
Published: August 2015

Abstract A method is proposed to determine the mechanical properties of retina based on in vivo experiments and numerical simulations. First, saline water was injected into the anterior chamber of the right eye of a cat to cause acute high intraocular pressure. After the eye was scanned using optical coherence tomography under different acute high intraocular pressures, the images of the retina in vivo were obtained and the thickness of the retina was calculated. Then, the three-dimensional structure of the optic nerve head including the retina and the choroid were reconstructed using image processing technology. Three different material models for the retina and the choroid were taken and the finite element models of the optic nerve head were constructed. Finally, an inverse method was proposed to determine the parameters of a constitutive model of the retina and of the choroid simultaneously. The results showed that the deformation of the retina can be properly simulated taking into consideration the nonlinear elastic properties of the retina and of the choroid.
Hemodynamics analyses in treated and untreated carotid arteries of the same patient: A preliminary study based on three patient cases
Authors: Mei Yuqian , Müller-Eschner Matthias , Yi Jie , Zhang Zhaotong , Chen Duanduan , Kronlage Moritz , von Tengg-Kobligk Hendrik , Kauczor Hans-Ulrich , Böckler Dittmar , Demirel Serdar 
Published: August 2015

Abstract Carotid atherosclerotic disease is highly related to cerebrovascular events. Carotid endarterectomy is the common operation method to treat this disease. In this study, hemodynamics analyses are performed on the carotid arteries in three patients, whose right carotid artery had been treated by carotid endarterectomy and the left carotid artery remained untreated. Flow and loading conditions are compared between these treated and untreated carotid arteries and evaluation of the operative results is discussed. Patient-specific models are reconstructed from MDCT data. Intraoperative ultrasound flow measurements are performed on the treated carotid arteries and the obtained data are used as the boundary conditions of the models and the validations of the computational results. Finite volume method is employed to solve the transport equations and the flow and loading conditions of the models are reported. The results indicate that: (i) in two of the three patients, the internal-to-external flow rate ratio in the untreated carotid artery is larger than that in the treated one, and the average overall flow split ratio by summing up the data of both the left and right carotid arteries is about 2.15; (ii) in the carotid bulb, high wall shear stress occurs at the bifurcation near the external carotid artery in all of the cases without hard plaques; (iii) the operated arteries present low time-averaged wall shear stress at the carotid bulb, especially for the treated arteries with patch technique, indicating the possibility of the recurrence of stenosis; (iv) high temporal gradient of wall shear stress (>35 Pa/s) is shown in the narrowing regions along the vessels; and (v) in the carotid arteries without serious stenosis, the maximum velocity magnitude during mid-diastole is 32∼37% of that at systolic peak, however, in the carotid artery with 50% stenosis by hard plaques, this value is nearly doubled (64%). The computational work quantifies flow and loading distributions in the treated and untreated carotid arteries of the same patient, contributing to evaluation of the operative results and indicating the recurrent sites of potential atheromatous plaques.
Clinical study of single-visit root canal treatment with a nickel-titanium (Ni-Ti) rotary instrument combined with different ultrasonic irrigation solutions for elderly patients with chronic apical periodontitis
Authors: Tang Zhenyu , Wang Hui , Jiang Shiyong 
Published: August 2015

Abstract The study involved 300 elderly patients with chronic periapical periodontitis. The patients were randomly assigned into three groups. The treatment for group A used a Mtwo Ni-Ti rotary instrument combined with ultrasonic irrigation of a 2.5% NaOCl solution. The group B used the same instrument combined with ultrasonic irrigation of an active silver ion antibacterial solution. The group C used the same instrument combined with syringe irrigation of a 2.5% NaOCl solution. The root canal fillings were performed immediately after canal preparation. Twenty-four hours after the procedure, patients self-assessed pain levels according to the VAS table. The three groups returned after seven days so their postoperative acute reactions could be evaluated clinically. After six and twelve months, efficacy was evaluated. The self-assessed pain levels for group A and B were significantly lower than group C. The incidence of postoperative acute reactions after seven days for group A and B were significantly lower than those of group C. The effective rates after six and twelve months did not differ among these groups. The single-visit root canal treatment with a nickel-titanium rotary instrument combined with ultrasonic irrigation for elderly patients with chronic periapical periodontitis achieved short and long term efficacy and stability.
Numerical analysis of the effect of side holes of a double J stent on flow rate and pattern
Authors: Kim Kyung-Wuk , Choi Young Ho , Lee Seung Bae , Baba Yasutaka , Kim Hyoung-Ho , Suh Sang-Ho 
Published: August 2015

Abstract A double J stent has been used widely these days for patients with a ureteral stenosis or with renal stones and lithotripsy. The stent has multiple side holes in the shaft, which supply detours for urine flow. Even though medical companies produce various forms of double J stents that have different numbers and positions of side holes in the stent, the function of side holes in fluid dynamics has not been studied well. Here, the flow rate and pattern around the side holes of a double J stent were evaluated in curved models of a stented ureter based on the human anatomy and straight models for comparison. The total flow rate was higher in the stent with a greater number of side holes. The inflow and outflow to the stent through the side holes in the curved ureter was more active than in the straight ureter, which means the flow through side holes exists even in the ureter without ureteral stenosis or occlusion and even in the straight ureter. When the diameter of the ureter changed, the in-stent flow rate in the ureter did not change and the extraluminal flow rate was higher in the ureter with a greater diameter.
Improved walking ability with wearable robot-assisted training in patients suffering chronic stroke
Authors: Li Lifang , Ding Li , Chen Na , Mao Yurong , Huang Dongfeng , Li Le 
Published: August 2015

Abstract Wearable robotic devices provide safe and intensive rehabilitation, enabling repeated motions for motor function recovery in stroke patients. The aim of this small case series was to demonstrate the training effects of a three-week robotic leg orthosis, and to investigate possible mechanisms of the sensory-motor alterations and improvements by using gait analysis and EMG. Three survivors of chronic strokes participated in robot-assisted gait therapy for three weeks. EMG signals from the rectus femoris (RF), tibialis anterior (TA), biceps femoris (BF), and medial gastrocnemius (MG), as well as kinetics and kinematics data of the lower limb, were recorded before and after the training. The normalized root mean squared (RMS) values of the muscles, the joint moments, joint angles, and the results of two clinical scales (Berg Balance scale, BBS, and the lower extremity subscale of Fugl-Meyer assessment, LE-FMA) were used for analysis. All participants experienced improved balance and functional performances and increased BBS and LE-FMA scores. The EMG results showed there was an increase of the normalized RMS values of the MG and BF on the affected side. Additionally, EMG activities of the agonist and antagonist pair (i.e. RF and BF) appeared to return to similar levels after training. The peak moment of hip flexor, knee extensor, and plantar flexor, which all contributed to push-off power, were found to have increased after training. In summary, the three-week training period using the wearable RLO improved the three participants’ gait performance by regaining push-off power and improved muscle activation and walking speed.