Pub Date : 2015-08-19DOI: 10.4172/1662-100X.S1.003
ace Martin, James J. Hickman
T muscle spindle and its associated sensory neurons form the afferent sensorimotor circuit of motor function. In order to better understand the physiology of this circuit so as to use it to address its relevant diseases; this study aims to establish an in vitro model of this spindle-sensory unit by integrating the cells comprising this system with microelectromechanical (MEMS) technology. A defined cell culture system has been developed to support the in vitro differentiation of human intrafusal muscle fibers (muscle fibers inside the muscle spindle) and human proprioceptive sensory neurons as well as their connections. A BioMEMS chip has been designed and fabricated to allow for the integration and functional analysis of this biological system. Intrafusal muscle fibers have been grown and activated by controlled stretching of the cantilever sensor. This non-invasive test bed will allow for controlled and long-term monitoring, interrogation and high control analysis of the sensorimotor unit of the human neuromuscular reflex arc. It could have use for applications not only for emulation of human health and disease, but also for the construction of relevant robotic systems.
{"title":"A biomechanical device for human sensorimotor function","authors":"ace Martin, James J. Hickman","doi":"10.4172/1662-100X.S1.003","DOIUrl":"https://doi.org/10.4172/1662-100X.S1.003","url":null,"abstract":"T muscle spindle and its associated sensory neurons form the afferent sensorimotor circuit of motor function. In order to better understand the physiology of this circuit so as to use it to address its relevant diseases; this study aims to establish an in vitro model of this spindle-sensory unit by integrating the cells comprising this system with microelectromechanical (MEMS) technology. A defined cell culture system has been developed to support the in vitro differentiation of human intrafusal muscle fibers (muscle fibers inside the muscle spindle) and human proprioceptive sensory neurons as well as their connections. A BioMEMS chip has been designed and fabricated to allow for the integration and functional analysis of this biological system. Intrafusal muscle fibers have been grown and activated by controlled stretching of the cantilever sensor. This non-invasive test bed will allow for controlled and long-term monitoring, interrogation and high control analysis of the sensorimotor unit of the human neuromuscular reflex arc. It could have use for applications not only for emulation of human health and disease, but also for the construction of relevant robotic systems.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"2013 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74228068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-08-19DOI: 10.4172/1662-100X.S1.001
Yong Wang
A two-dimensional anatomically based mathematical model of the human knee joint was developed to understand its biomechanics in deep flexion. The model was used to determine the internal knee loads as it simulates isometric quadriceps and hamstring co-contractions at different flexion angles during deep squat. It was found that in order to achieve deep flexion, large muscle forces are required, resulting in large tibio-femoral contact forces. In deep flexion, the femoral contact point was located on the most proximal point of the posterior condyle, location which was not affected by the level of quad activation. Conversely, the location of the tibial contact point was highly affected by the level of quad activation. Both anterior and posterior fiber bundles of the posterior cruciate ligament were found to carry high loads when the knee is maximally flexed. These results point to the important role of the posterior cruciate ligament in this position, and suggest the necessity of retaining this ligament during total knee replacement (TKR) procedures that allows for maximum flexion angles. Furthermore, the present data provide an explanation why most TKR's do not allow deep flexion: while contact occurs on the most proximal points of the posterior condyles in normal knees, this portion of the condyles is not presently resurfaced when performing a TKR.
{"title":"Programmable materials for mechanobiology","authors":"Yong Wang","doi":"10.4172/1662-100X.S1.001","DOIUrl":"https://doi.org/10.4172/1662-100X.S1.001","url":null,"abstract":"A two-dimensional anatomically based mathematical model of the human knee joint was developed to understand its biomechanics in deep flexion. The model was used to determine the internal knee loads as it simulates isometric quadriceps and hamstring co-contractions at different flexion angles during deep squat. It was found that in order to achieve deep flexion, large muscle forces are required, resulting in large tibio-femoral contact forces. In deep flexion, the femoral contact point was located on the most proximal point of the posterior condyle, location which was not affected by the level of quad activation. Conversely, the location of the tibial contact point was highly affected by the level of quad activation. Both anterior and posterior fiber bundles of the posterior cruciate ligament were found to carry high loads when the knee is maximally flexed. These results point to the important role of the posterior cruciate ligament in this position, and suggest the necessity of retaining this ligament during total knee replacement (TKR) procedures that allows for maximum flexion angles. Furthermore, the present data provide an explanation why most TKR's do not allow deep flexion: while contact occurs on the most proximal points of the posterior condyles in normal knees, this portion of the condyles is not presently resurfaced when performing a TKR.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85068292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.1
M. Farid, Zhao Gang, Tran Linh Khuong, Zhuang-zhi Sun, Naveed ur Rehman
Biomimetic is the field of engineering in which biological structures and functions are analyzed and are used as the basis for the design and manufacturing of machines. Insects are the most populated creature and present everywhere in the world and can survive the most hostile environmental situations. IPMC is a smart material which has exhibited a significant bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing.In this paper, five different contributions are made. Firstly, a two link grasshopper knee joint physical model is presented in which the actuation force required for moving the knee is provided by the IPMC material. This material constitutes one link of the linkage. Secondly, inverse kinematic model has been developed for the linkage. Thirdly, the system of equations is solved by proposing solutions to the known transcendental functions with unknown coefficients. Fourthly, wolfram mathematica is employed for the simulation of the model. Finally, angles, velocity and acceleration of the links are analyzed based on the simulation results. The simulation results show that the tibia is displaying a lag in time from the femur verifying that it is operated by the force provided by the femur (IPMC). Also, it verified the flexible nature of the IPMC material through multiple peaks and troughs in the graphs. The angles range of the tibia is found quite admirable and it is believed that the IPMC material can add a new horizon to the manufacturing of small biomimetic equipment and low force actuated manipulators.
{"title":"Grasshopper Knee Joint – Inverse Kinematic Modeling and Simulation of Ionic Polymer Metal Composites (IPMC) Actuators","authors":"M. Farid, Zhao Gang, Tran Linh Khuong, Zhuang-zhi Sun, Naveed ur Rehman","doi":"10.4028/www.scientific.net/JBBTE.19.1","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.1","url":null,"abstract":"Biomimetic is the field of engineering in which biological structures and functions are analyzed and are used as the basis for the design and manufacturing of machines. Insects are the most populated creature and present everywhere in the world and can survive the most hostile environmental situations. IPMC is a smart material which has exhibited a significant bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing.In this paper, five different contributions are made. Firstly, a two link grasshopper knee joint physical model is presented in which the actuation force required for moving the knee is provided by the IPMC material. This material constitutes one link of the linkage. Secondly, inverse kinematic model has been developed for the linkage. Thirdly, the system of equations is solved by proposing solutions to the known transcendental functions with unknown coefficients. Fourthly, wolfram mathematica is employed for the simulation of the model. Finally, angles, velocity and acceleration of the links are analyzed based on the simulation results. The simulation results show that the tibia is displaying a lag in time from the femur verifying that it is operated by the force provided by the femur (IPMC). Also, it verified the flexible nature of the IPMC material through multiple peaks and troughs in the graphs. The angles range of the tibia is found quite admirable and it is believed that the IPMC material can add a new horizon to the manufacturing of small biomimetic equipment and low force actuated manipulators.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"27 1","pages":"1 - 11"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88424195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.25
Jianfeng Sui, Ya Li Liu, Linhong Ji
Effects of conventional exercise training of robot to stroke patients are not too satisfying, and efficient methods of training are unclear. To test how the non-rhythmical load stimulation affects cerebral cortex by analyzing the coherence between electroencephalographic signals (EEGs) and electromyographic signals (EMGs). Ten healthy subjects, all subjects have no history of neurological diseases (6 men and 4 women, mean age: 24.5 years, range: 22-28). Subjects lay on the experimental platform 75°with respect to the ground, feet on support plates and close to the ground. When non-rhythmical stimulation was performed randomly, one hinge was released and the respected braced force between the foot and support plate disappeared, which caused the corresponding ankle to extend suddenly without relative displacement between the foot and the support plate. Surface EMG signals from tibialis anterior (TA) muscles and EEG signals from cerebral cortex area Cz were recorded, and coherence between them were analyzed. The mean maximum EEG-EMG coherence of the non-rhythmical stimulation side of the ten subjects was consistent across all (9 of 10) within β range (13-30 Hz), and the average value of all in the stimulated side was 23.581Hz. While the mean maximum EEG-EMG coherence of the still side were consistent across all (9 of 10) within α range (8-13 Hz). Our findings suggest that non-rhythmical stimulation to lower limb can stimulate effectively the corresponding area of the cerebral cortex, and this idea could be applied in rehabilitation of central nervous system diseases like stroke.
{"title":"Effect of Unilateral Non-Rhythmical Stimulation on Bilateral Cerebral Cortex and Muscle Activation in People","authors":"Jianfeng Sui, Ya Li Liu, Linhong Ji","doi":"10.4028/www.scientific.net/JBBTE.19.25","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.25","url":null,"abstract":"Effects of conventional exercise training of robot to stroke patients are not too satisfying, and efficient methods of training are unclear. To test how the non-rhythmical load stimulation affects cerebral cortex by analyzing the coherence between electroencephalographic signals (EEGs) and electromyographic signals (EMGs). Ten healthy subjects, all subjects have no history of neurological diseases (6 men and 4 women, mean age: 24.5 years, range: 22-28). Subjects lay on the experimental platform 75°with respect to the ground, feet on support plates and close to the ground. When non-rhythmical stimulation was performed randomly, one hinge was released and the respected braced force between the foot and support plate disappeared, which caused the corresponding ankle to extend suddenly without relative displacement between the foot and the support plate. Surface EMG signals from tibialis anterior (TA) muscles and EEG signals from cerebral cortex area Cz were recorded, and coherence between them were analyzed. The mean maximum EEG-EMG coherence of the non-rhythmical stimulation side of the ten subjects was consistent across all (9 of 10) within β range (13-30 Hz), and the average value of all in the stimulated side was 23.581Hz. While the mean maximum EEG-EMG coherence of the still side were consistent across all (9 of 10) within α range (8-13 Hz). Our findings suggest that non-rhythmical stimulation to lower limb can stimulate effectively the corresponding area of the cerebral cortex, and this idea could be applied in rehabilitation of central nervous system diseases like stroke.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"3 1","pages":"25 - 33"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75632450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.13
M. Farid, Zhao Gang, Tran Linh Khuong, Zhuang-zhi Sun
Biomimetic is the field of engineering which involves analyzing the biological beings and incorporating their designs and systems for manufacturing mechanical systems. An Ionic Polymer metal composite (IPMC) is a smart material that displays a significant bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing. In this paper, a two-link biomimetic knee joint mechanism of a grass hopper is presented. Secondly, an IPMC pair of strips is proposed as a link that enables the actuating force which is modeled on the basis of the grass hopper's leg. Thirdly, dynamic model is developed for the proposed mechanism through Lagrangian mechanics. Fourthly, power series is utilized for the solution of the non-linear transcendental model. Wolfram mathematica is employed for the simulation of the model. Finally, the effect of torque is analyzed by varying the actuating torque. It is concluded that actuating torque is directly proportional to the angles moved and inversely proportional to the potential energies of the linkage. Furthermore, a stiffer and more vibrant linkage is observed as per simulation results. These results are validated theoretically. Our simulation results indicate that the proposed IPMC has the potential for utilization in small biomimetic applications like insects robots joints activation, underwater fish fins, surgical grippers, synthetic ventricular muscles and human catheter system for endoscopic surgery and diagnostics etc.
{"title":"Grasshopper Knee Joint - Torque Analysis of Actuators Using Ionic Polymer Metal Composites (IPMC)","authors":"M. Farid, Zhao Gang, Tran Linh Khuong, Zhuang-zhi Sun","doi":"10.4028/www.scientific.net/JBBTE.19.13","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.13","url":null,"abstract":"Biomimetic is the field of engineering which involves analyzing the biological beings and incorporating their designs and systems for manufacturing mechanical systems. An Ionic Polymer metal composite (IPMC) is a smart material that displays a significant bending and tip force after the application of a low voltage. It is light-weighted, flexible, easily actuated, multi-directional applicable and requires simple manufacturing. In this paper, a two-link biomimetic knee joint mechanism of a grass hopper is presented. Secondly, an IPMC pair of strips is proposed as a link that enables the actuating force which is modeled on the basis of the grass hopper's leg. Thirdly, dynamic model is developed for the proposed mechanism through Lagrangian mechanics. Fourthly, power series is utilized for the solution of the non-linear transcendental model. Wolfram mathematica is employed for the simulation of the model. Finally, the effect of torque is analyzed by varying the actuating torque. It is concluded that actuating torque is directly proportional to the angles moved and inversely proportional to the potential energies of the linkage. Furthermore, a stiffer and more vibrant linkage is observed as per simulation results. These results are validated theoretically. Our simulation results indicate that the proposed IPMC has the potential for utilization in small biomimetic applications like insects robots joints activation, underwater fish fins, surgical grippers, synthetic ventricular muscles and human catheter system for endoscopic surgery and diagnostics etc.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"41 1","pages":"13 - 23"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74046352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.99
E. Stodolak-Zych, Anna Łuszcz, E. Menaszek, Anna Ścisłowska-Czarencka
A bioresorbable polymer poly-ε-caprolactone (PCL) was tested in order to obtain porous materials suitable for membranes. The commercial PCL with various molecular weights (2kDa, 60kDa, 80 kDa) but similar polydispersity has been chosen. The membranes were produced by the casting method and the membrane materials underwent microstructure investigation (SEM) to assess the size of pores and an average porosity of the membranes. The membranes permeability was established by means of ultrafiltration. Also wettabilility and basic mechanical properties (such as: tensile strength Rm, Youngs modulus, E) were established. The membranes durability was tested in in vitro conditions (PBS/37°C) by monitoring of changes by means of ion conductivity measurement and changes in the molecular weight (the Ubbelohde method). The porous materials were tested towards biocompatibility, i.e. the membrane was contacted with the osteoblast line of NHOst cells (viability test, cells morphology). Non-perforated PCL foil was used as a reference material. The best physicochemical, mechanical and biological properties of the membranes were observed in case of application of PCL with molecular weight of 60 kDa.
{"title":"Resorbable Polymer Membranes for Medical Applications","authors":"E. Stodolak-Zych, Anna Łuszcz, E. Menaszek, Anna Ścisłowska-Czarencka","doi":"10.4028/www.scientific.net/JBBTE.19.99","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.99","url":null,"abstract":"A bioresorbable polymer poly-ε-caprolactone (PCL) was tested in order to obtain porous materials suitable for membranes. The commercial PCL with various molecular weights (2kDa, 60kDa, 80 kDa) but similar polydispersity has been chosen. The membranes were produced by the casting method and the membrane materials underwent microstructure investigation (SEM) to assess the size of pores and an average porosity of the membranes. The membranes permeability was established by means of ultrafiltration. Also wettabilility and basic mechanical properties (such as: tensile strength Rm, Youngs modulus, E) were established. The membranes durability was tested in in vitro conditions (PBS/37°C) by monitoring of changes by means of ion conductivity measurement and changes in the molecular weight (the Ubbelohde method). The porous materials were tested towards biocompatibility, i.e. the membrane was contacted with the osteoblast line of NHOst cells (viability test, cells morphology). Non-perforated PCL foil was used as a reference material. The best physicochemical, mechanical and biological properties of the membranes were observed in case of application of PCL with molecular weight of 60 kDa.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"10 1","pages":"108 - 99"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82374717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.35
M. Wasim, R. S. Malik, M. Tufail, Ahsan Ullah Jutt, R. Ahmad, K. M. Deen
Hydroxyapatite was synthesized from bovine cortical bone by thermal decomposition method. The chemically cleaned bone was heated to 160 °C for 48 hour to remove moisture and any organic contents followed by decomposition in muffle furnace at 850 °C for 6 hours. The so-obtained white powder was characterized by Fourier Transform Infrared (FT-IR) spectroscopy and X-Ray Diffraction (XRD), SEM and EDX method. The FT-IR results proved the existence of hydroxyl (OH-) and phosphate (PO4-3) groups in the powder. XRD analysis was in support to the FT-IR spectrum, however, an additional phase of tri-calcium phosphate (TCP) was also observed as an impurity, SEM shows the surface morphology & EDX gives the Calcium (Ca) to Phosphorous (P) ratio. Key Words: Hydroxyapatite; Thermal Decomposition, Calcination
{"title":"Synthesis and Characterization of Hydroxyapatite Powder from Natural Bovine Bone","authors":"M. Wasim, R. S. Malik, M. Tufail, Ahsan Ullah Jutt, R. Ahmad, K. M. Deen","doi":"10.4028/www.scientific.net/JBBTE.19.35","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.35","url":null,"abstract":"Hydroxyapatite was synthesized from bovine cortical bone by thermal decomposition method. The chemically cleaned bone was heated to 160 °C for 48 hour to remove moisture and any organic contents followed by decomposition in muffle furnace at 850 °C for 6 hours. The so-obtained white powder was characterized by Fourier Transform Infrared (FT-IR) spectroscopy and X-Ray Diffraction (XRD), SEM and EDX method. The FT-IR results proved the existence of hydroxyl (OH-) and phosphate (PO4-3) groups in the powder. XRD analysis was in support to the FT-IR spectrum, however, an additional phase of tri-calcium phosphate (TCP) was also observed as an impurity, SEM shows the surface morphology & EDX gives the Calcium (Ca) to Phosphorous (P) ratio. Key Words: Hydroxyapatite; Thermal Decomposition, Calcination","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"7 1","pages":"35 - 42"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81607036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.43
M. Bousnaki, P. Koidis
When used as an implanted material, titanium (Ti) surface controls the subsequent biological reactions and leads to tissue integration. Cells interactions with the surface, through a protein layer that is being formed from the moment Ti surface comes in contact with blood and its components, and indeed this protein layer formation, are regulated by surface properties such as topography, chemistry, charge and surface energy. Currently, the implementation of nanotechnology, in an attempt to support mimicking the natural features of extracellular matrix, has provided novel approaches for understanding and translating surface mechanisms whose modification and tailoring are expected to lead to enhanced cell activity and improved integration. Despite the fact that there has been extensive research on this subject, the sequence of interactions that take place instantly after the exposure of the implanted material into the biologic microenvironment are not well documented and need further investigation as well as the optimization of characteristics of Ti surface. This review, including theoretical and experimental studies, summarizes some of the latest advances on the Ti surface concerning modifications on surface properties and how these modifications affect biomolecular reactions and also attempts to present the initial adsorption mechanism of water and protein molecules to the surface.
{"title":"Advances on Biomedical Titanium Surface Interactions","authors":"M. Bousnaki, P. Koidis","doi":"10.4028/www.scientific.net/JBBTE.19.43","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.43","url":null,"abstract":"When used as an implanted material, titanium (Ti) surface controls the subsequent biological reactions and leads to tissue integration. Cells interactions with the surface, through a protein layer that is being formed from the moment Ti surface comes in contact with blood and its components, and indeed this protein layer formation, are regulated by surface properties such as topography, chemistry, charge and surface energy. Currently, the implementation of nanotechnology, in an attempt to support mimicking the natural features of extracellular matrix, has provided novel approaches for understanding and translating surface mechanisms whose modification and tailoring are expected to lead to enhanced cell activity and improved integration. Despite the fact that there has been extensive research on this subject, the sequence of interactions that take place instantly after the exposure of the implanted material into the biologic microenvironment are not well documented and need further investigation as well as the optimization of characteristics of Ti surface. This review, including theoretical and experimental studies, summarizes some of the latest advances on the Ti surface concerning modifications on surface properties and how these modifications affect biomolecular reactions and also attempts to present the initial adsorption mechanism of water and protein molecules to the surface.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"55 1","pages":"43 - 64"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82827165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.65
Wei Zheng, Gang Liu, Cheng Yan, Yin Xiao, X. Miao
Calcium phosphate ceramic scaffolds have been widely investigated for bone tissue engineering due to their excellent biocompatibility and biodegradation. Unfortunately, they have low mechanical properties, which inversely restrict their wide applications in load-bearing bone tissue engineering. In this study, porous Si-doped tri-calcium phosphate (TCP) ceramics with a high porosity (~65%) and with interconnected macrotubes (~0.8mm in diameter) and micropores (5-100 μm) were prepared by firing hydroxyapatite (HA)/ bioactive glass-impregnated acrylontrile butadiene styrene (ABS) templates at 1400 °C. Results indicated that the cylindrical scaffolds had a higher compressive strength than the cubic scaffolds and the smallest cylindrical scaffold had a highest compressive strength (14.68+0.2MPa). Additional studies of cell attachment and MTT cytotoxicity assay proved the bioactivity and biocompatibility of the Si-doped TCP scaffolds.
{"title":"Strong and Bioactive Tri-Calcium Phosphate Scaffolds with Tube-Like Macropores","authors":"Wei Zheng, Gang Liu, Cheng Yan, Yin Xiao, X. Miao","doi":"10.4028/www.scientific.net/JBBTE.19.65","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.65","url":null,"abstract":"Calcium phosphate ceramic scaffolds have been widely investigated for bone tissue engineering due to their excellent biocompatibility and biodegradation. Unfortunately, they have low mechanical properties, which inversely restrict their wide applications in load-bearing bone tissue engineering. In this study, porous Si-doped tri-calcium phosphate (TCP) ceramics with a high porosity (~65%) and with interconnected macrotubes (~0.8mm in diameter) and micropores (5-100 μm) were prepared by firing hydroxyapatite (HA)/ bioactive glass-impregnated acrylontrile butadiene styrene (ABS) templates at 1400 °C. Results indicated that the cylindrical scaffolds had a higher compressive strength than the cubic scaffolds and the smallest cylindrical scaffold had a highest compressive strength (14.68+0.2MPa). Additional studies of cell attachment and MTT cytotoxicity assay proved the bioactivity and biocompatibility of the Si-doped TCP scaffolds.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"136 1","pages":"65 - 75"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80382703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-03-01DOI: 10.4028/www.scientific.net/JBBTE.19.77
Xiaoming Tian, Xiongbaio Chen
Cell-seeded hydrogel scaffolds have been widely used in various tissue engineering applications due to their excellent biocompatibility and biomimetic properties. One of the critical issues in successful use of hydrogel scaffolds is their mechanical properties. Since cells and hydrogels are physically different materials, the cells encapsulated in the hydrogels can change profoundly the mechanical properties of the hydrogel scaffolds. In this research, the effects of Schwann cell density on mechanical properties of alginate hydrogel scaffolds were investigated. It was found that increase of cell density decreases the strength of the scaffolds. It was also found that the Ogden model can best describe the mechanical properties of the scaffolds under the strain of 45% at varying cell densities. Based on the cell density-dependant mechanical properties, a simulation was performed to study the local stresses of on cells when cells are subjected to loading. Simulation shows that at the same strain, the stress concentration on cells decreases as the cell density increases. The experimental and simulation results obtained in this paper will allow one to rigorously design scaffolds with desired mechanical properties and provide a clue to avoid mechanical cell injury.
{"title":"Effects of Cell Density on Mechanical Properties of Alginate Hydrogel Tissue Scaffolds","authors":"Xiaoming Tian, Xiongbaio Chen","doi":"10.4028/www.scientific.net/JBBTE.19.77","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JBBTE.19.77","url":null,"abstract":"Cell-seeded hydrogel scaffolds have been widely used in various tissue engineering applications due to their excellent biocompatibility and biomimetic properties. One of the critical issues in successful use of hydrogel scaffolds is their mechanical properties. Since cells and hydrogels are physically different materials, the cells encapsulated in the hydrogels can change profoundly the mechanical properties of the hydrogel scaffolds. In this research, the effects of Schwann cell density on mechanical properties of alginate hydrogel scaffolds were investigated. It was found that increase of cell density decreases the strength of the scaffolds. It was also found that the Ogden model can best describe the mechanical properties of the scaffolds under the strain of 45% at varying cell densities. Based on the cell density-dependant mechanical properties, a simulation was performed to study the local stresses of on cells when cells are subjected to loading. Simulation shows that at the same strain, the stress concentration on cells decreases as the cell density increases. The experimental and simulation results obtained in this paper will allow one to rigorously design scaffolds with desired mechanical properties and provide a clue to avoid mechanical cell injury.","PeriodicalId":15198,"journal":{"name":"Journal of Biomimetics, Biomaterials and Tissue Engineering","volume":"1 1","pages":"77 - 85"},"PeriodicalIF":0.0,"publicationDate":"2014-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81273768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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