BioRN: Bio-Inspired Engineering (Topic)最新文献

{"title":"Personalized Baghdadite Scaffolds: Stereolithography, Mechanics and In vivo Testing","authors":"M. Mirkhalaf, Aiken Dao, A. Schindeler, D. Little, C. Dunstan, H. Zreiqat","doi":"10.2139/ssrn.3737306","DOIUrl":"https://doi.org/10.2139/ssrn.3737306","url":null,"abstract":"An ongoing challenge in the field of orthopedics is to produce a clinically relevant synthetic ceramic scaffold for the treatment of 'critical-sized' bone defects, which cannot heal without intervention. We had developed a bioactive ceramic (Baghdadite, Ca₃ZrSi₂O₉) and demonstrated its outstanding bioactivity using traditional manufacturing techniques. Here, we report on the development of a versatile stereolithography printing technology that enables fabrication of anatomically-shaped and -sized Baghdadite scaffolds. We assessed the in vivo bioactivity of these scaffolds in co-delivering of bone morphogenetic protein-2 (BMP2) and zoledronic acid (ZA) through bioresorbable coatings to induce bone formation and increase retention in a rat model of heterotopic ossification. Micro-computed tomography, histology, mechanical tests pre- and post-implantation, and mechanical modelling were used to assess bone ingrowth and its effects on the mechanics of the scaffolds. Bone ingrowth and the consequent mechanical properties of the scaffolds improved with increasing BMP2 dose. Co-delivery of ZA with BMP2 further improved this outcome. The significant bone formation within the scaffolds functionalized with 10 µg BMP2 and 2 µg ZA made them 2.3 × stiffer and 2.7 × stronger post-implantation and turned these inherently brittle scaffolds into a tough and deformable material. The effect of bone ingrowth on the mechanical properties of scaffolds were captured in a mechanical model that can be used in future clinical studies for non-destructive evaluation of scaffold's stiffness and strength as new bone forms. These results support the practical utilization of our versatile stereolithographic printing methods and BMP2/ZA functionalization to create fit-for-purpose personalized implants for clinical trials. STATEMENT OF SIGNIFICANCE: : In this study, we addressed a long-standing challenge of developing a ceramic printing technology that enables fabrication of customizable anatomically-shaped and -sized bioceramic scaffolds with precise internal architectures using an inexpensive desktop printer. We also addressed another challenge related to delivery of pharmaceuticals. BMP2, currently available as a bone-inducing bioactive protein, is clinically administered in a collagen scaffold that has limited moldability and poor mechanical properties. The comparably stiffer and stronger 3D printed personalized Baghdadite scaffolds developed here can be readily functionalized with bioresorbable coatings containing BMP2 ± ZA. These innovations considerably improve on the prior art and are scalable for use in human surgery.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125358907","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}

{"title":"Dual 3D Printing for Vascularized Bone Tissue Regeneration","authors":"Sung Yun Hann, H. Cui, Timothy Esworthy, Xuan Zhou, Se-jun Lee, M. Plesniak, Lijie Grace Zhang","doi":"10.2139/ssrn.3708592","DOIUrl":"https://doi.org/10.2139/ssrn.3708592","url":null,"abstract":"The development of sufficient vascular networks is crucial for the successful fabrication of tissue constructs for regenerative medicine, as vascularization is essential to perform the metabolic functions of tissues, such as nutrient transportation and waste removal. In recent years, efforts to 3D print vascularized bone have gained substantial attention, as bone disorders and defects have a marked impact on the older generations of society. However, conventional and previous 3D printed bone studies have been plagued by the difficulty in obtaining the nanoscale geometrical precision necessary to recapitulate the distinct characteristics of natural bone. Additionally, the process of developing truly biomimetic vascularized bone tissue has been historically complex. In this study, a biomimetic nano-bone tissue construct with a perfusable, endothelialized vessel channel was developed using a combination of simple stereolithography (SLA) and fused deposition modeling (FDM) 3D printing systems. The perfusable vessel channel was created within the SLA printed bone scaffold using an FDM printed polyvinyl alcohol (PVA) sacrificial template. Within the fabricated constructs, bone tissue was formed through the osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs), and distinct capillaries sprouted through the angiogenesis of the endothelialized vessel channel after human umbilical vein endothelial cells (HUVECs) had been perfused throughout. Furthermore, the fabricated constructs were evaluated in physiologically relevant culture conditions to predict tissue development after implantation in the human body. The experimental results revealed that the custom-designed bioreactor with an hMSC-HUVEC co-culture system enhanced the formation of vascular networks and the osteogenic maturation of the constructs for up to 20 days of observation.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129846932","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}

{"title":"The Viscoelastic Inflation Response of the Sclera Varies between Preconditioning Protocols","authors":"G. Bianco, Alexander M Levy, R. Grytz, M. Fazio","doi":"10.2139/ssrn.3734108","DOIUrl":"https://doi.org/10.2139/ssrn.3734108","url":null,"abstract":"Preconditioning by repeated cyclic loads is routinely used in ex vivo mechanical testing of soft biological tissues. The goal of preconditioning is to achieve a steady and repeatable mechanical response and to measure material properties that are representative of the in vivo condition. Preconditioning protocols vary across studies, and their effect on the viscoelastic response of tested soft tissue is typically not reported or analyzed. We propose a methodology to systematically analyze the preconditioning process with application to inflation testing. We investigated the effect of preconditioning on the viscoelastic inflation response of tree shrew sclera using two preconditioning protocols: (i) continuous cyclic loading-unloading without rest and (ii) cyclic loading-unloading with 15-min rest between cycles. Scleral surface strain was measured using three-dimensional Digital Image Correlation (3D-DIC). We used five variables of characterizing features of the stress-strain loop curve to compare the two preconditioning protocols. Our results showed protocol-dependent differences in the tissue response during preconditioning and at the preconditioned state. Incorporating a resting time between preconditioning cycles significantly decreased the number of cycles (10.5 ± 2.9 cycles vs. 3.1 ± 0.5 cycles, p<0.001) but increased the total time (15.8 ± 4.4 min vs. 51.2 ± 8.3 min, p<0.001) needed to reach preconditioned state. At the preconditioned state, 2 of 5 characteristic variables differed significantly between protocols: hysteresis loop area (difference=0.023 kJ/m 3 , p=0.0020) and elastic modulus at high IOP (difference=0.240 MPa, p=0.0238). Our results suggest that the analysis of the preconditioning process is an essential part of inflation experiments and a prerequisite to properly characterize the tissue viscoelastic response. Furthermore, material properties obtained at the preconditioned state cannot be directly compared across studies with different preconditioning protocols.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126884292","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}

{"title":"Hydrophobic Ionic Liquid Tuning Hydrophobic Carbon to Superamphiphilicity for Reducing Diffusion Resistance in Liquid-Liquid Catalysis Systems","authors":"H. Fan, Jingxia Wang, Pingping Wu, Lei Zheng, J. Xiang, Hongliang Liu, B. Han, Lei Jiang","doi":"10.2139/ssrn.3726141","DOIUrl":"https://doi.org/10.2139/ssrn.3726141","url":null,"abstract":"Summary Designing superwettable surfaces for enhancing the reaction efficiencies has been being attracted attention. Herein, we report a distinct strategy that hydrophobic bis((trifluoromethyl)sulfonyl)imide (NTf2)-based ionic liquids can endow hydrophobic carbon with superhydrophilicity and superoleophilicity simultaneously via a one-step method in a large scale. Wettability mechanisms demonstrate that superhydrophilicity of the as-prepared carbon is mainly attributed to pyridinic N-oxide from the thermolysis of the NTf2 anion, whereas superoleophilicity of the carbon is provided by the elements C and F. Furthermore, superamphiphilic carbon can greatly eliminate the diffusion resistance thereby enhancing the reaction efficiencies in liquid-liquid systems by rapid enrichment of reactants around catalysts and increasing phase interfacial areas. This work provides a general route to construct superamphiphilic carbon that can greatly enhance the reaction efficiencies.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"145 8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125854778","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}

{"title":"Identifying the Optimal Pitch Angles for Bouligand Structures","authors":"Wenting Ouyang, B. Gong, Huan Wang, F. Scarpa, Yuexin Peng, H. Peng","doi":"10.2139/ssrn.3677353","DOIUrl":"https://doi.org/10.2139/ssrn.3677353","url":null,"abstract":"The Bouligand structure is a typical helicoidal architecture found in various crustaceans in which each layer rotates by a small angle relative to the adjacent one. We present a theoretical analysis to relate the rotation pitch angle to the mechanical performance (interlaminar shear property in this case) of laminas mimicking the Bouligand architecture. Theoretical models representing the helicoidal composite laminate stacking sequences are compared against experimental tests carried out on 32-layer helicoidal carbon fibre laminates with pitch angles of 6°, 9.1°, 12°, 25.7° where the 9.1° is the predicted optimal angle. The results show that this particular architecture with a pitch angle of 9.1° indeed attains the highest load-bearing capability and delays any catastrophic delamination. We also examine the role played by the rotation angle on the mechanisms like crack twisting and branching that are responsible for the superior performance. These results provide a fundamental basis to the design of helicoidal structures mimicking the Bouligand architecture.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130576332","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}

{"title":"Substrate Mechanics Dictates Cell-Cell Communication via Gap Junction in Stem Cells from Human Apical Papilla","authors":"Chenchen Zhou, Demao Zhang, Wei Du, Jing Zou, Xiaobing Li, Jing Xie","doi":"10.2139/ssrn.3490422","DOIUrl":"https://doi.org/10.2139/ssrn.3490422","url":null,"abstract":"It is recognized that the interaction between cells and their physical microenvironment plays a fundamental role in controlling cell behaviours and even in determining cell fate. Any change in the physical properties of the extracellular matrix (ECM), such as its topography, geometry or stiffness, controls this interaction. In the current study, we revealed a novel connection between the cell-matrix interaction and cell-cell communication that is mediated by interface stiffness, and elucidated this process in stem cells from human apical papilla (hSCAPs) in terms of mechanosensing, mechanotransduction and gap junction-mediated cell-cell communication. We first fabricated polydimethylsiloxane (PDMS) substrates with the same topography and geometry but different stiffnesses and found that the cell morphology of the hSCAPs actively changed to adapt to the difference in substrate stiffness, and we also found that the hSCAPs secreted more fibronectin in response to the stiff substrate. The focal adhesion plaques were changed by altering the expression of focal adhesion kinase (FAK) and paxillin. The FAK and paxillin bound to connexin 43 and, as a result, altered the gap junction formation. By a Lucifer yellow transfer assay, we further confirmed that the interface stiffness mediated cell-cell communication in living hSCAPs via changes in gap junction tunnels. The novel mechanics that mediated cell-cell communication through extracellular stiffness that was observed in this study show the great influence of the interaction between cells and their external physical microenvironment and stress the importance of microenvironmental mechanics in organ development and diseases.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114505502","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}

{"title":"Reconstruction of Inner Worm Passage of Quercus Mongolica Seeds","authors":"He Zhang","doi":"10.31033/ijemr.9.5.1","DOIUrl":"https://doi.org/10.31033/ijemr.9.5.1","url":null,"abstract":"This paper takes Quercus mongolica as an example, In order to determine the position of insects inside the Quercus mongolica seed. The seeds of Quercus mongolica were cut at a certain thickness to obtain an internal cross-sectional image of the seeds. In this paper, Canny and Hough algorithm are used to perform edge detection and line detection on unprocessed images, and determine the coordinate origin of the study area so that all study areas are in the same coordinate range. In order to obtain the position information of the insect path, based on the RGB principle, this paper designs a screening algorithm for the pixel points in the study area, and obtains the position information of the insect track. In order to observe the insect path more intuitively, this paper establishes a three-dimensional data model, and uses MATLAB to draw a three-dimensional structure diagram of the position information of the insect path, and shields the interference items such as seed germ to obtain a more accurate movement track of the insect.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131993937","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}

{"title":"Elastomeric Microlattice Impact Attenuators","authors":"Eric C. Clough, T. Plaisted, Zak C. Eckel, Kenneth Cante, Jacob M. Hundley, T. Schaedler","doi":"10.2139/ssrn.3427465","DOIUrl":"https://doi.org/10.2139/ssrn.3427465","url":null,"abstract":"Summary Impact-attenuating materials are designed to absorb impact energy through the collapse of pores within the material below a threshold force (or acceleration), thereby mitigating damage or injury. Recent advances in additive manufacturing techniques have enabled the fabrication of cellular materials with architected lattice topology. Here it is demonstrated that, via design of cellular architecture, the dynamic stress-strain response of elastomeric lattices can be tailored to achieve impact-attenuation performance exceeding state-of-the-art foams for both single- and multi-hit scenarios. The additional degrees of freedom in the design of the cellular architecture of lattice-based impact attenuators are then leveraged to optimize their performance for a typical helmet impact scenario wherein the contact area increases during deformation. An improvement over state-of-the-art vinyl-nitrile foam helmet pads is achieved during a standard helmet test, leading to lower head acceleration. This breakthrough could pave the way to helmets with improved injury protection.","PeriodicalId":382867,"journal":{"name":"BioRN: Bio-Inspired Engineering (Topic)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128633502","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}