Development of a preclinical natural porcine knee simulation model for the tribological assessment of osteochondral grafts in vitro

In computational biomechanics, two separate types of models have been used predominantly to enhance the understanding of the mechanisms of action of the lumbosacral spine (LSS): Finite element (FE) and musculoskeletal multibody (MB) models. To combine advantages of both models, hybrid FE-MB models are an increasingly used alternative. The aim of this paper is to develop, calibrate, and validate a novel passive hybrid FE-MB open-access simulation model of a ligamentous LSS using ArtiSynth. Based on anatomical data from the Male Visible Human Project, the LSS model is constructed from the L1-S1 rigid vertebrae interconnected with hyperelastic fiber-reinforced FE intervertebral discs, ligaments, and facet joints. A mesh convergence study, sensitivity analyses, and systematic calibration were conducted with the hybrid functional spinal unit (FSU) L4/5. The predicted mechanical responses of the FSU L4/5, the lumbar spine (L1-L5), and the LSS were validated against literature data from in vivo and in vitro measurements and in silico models. Spinal mechanical responses considered when loaded with pure moments and combined loading modes were total and intervertebral range of motions, instantaneous axes and centers of rotation, facet joint contact forces, intradiscal pressures, disc bulges, and stiffnesses. Undesirable correlations with the FE mesh were minimized, the number of crisscrossed collagen fiber rings was reduced to five, and the individual influences of specific anatomical structures were adjusted to in vitro range of motions. Including intervertebral motion couplings for axial rotation and nonlinear stiffening under increasing axial compression, the predicted kinematic and structural mechanics responses were consistent with the comparative data. The results demonstrate that the hybrid simulation model is robust and efficient in reproducing valid mechanical responses to provide a starting point for upcoming optimizations and extensions, such as with active skeletal muscles.

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A simplified simulation model and virtual reality visualization of tumour growth in vitro

Future Generation Computer Systems ◽

10.1016/s0167-739x(98)00011-9 ◽

1998 ◽

Vol 14 (1-2) ◽

pp. 79-89 ◽

Cited By ~ 4

Author(s):

Georgios S. Stamatakos ◽

Nikolaos K. Uzunoglu ◽

Konstantinos Delibasis ◽

Mersini Makropoulou ◽

Nikolaos Mouravliansky ◽

...

Keyword(s):

Virtual Reality ◽

Simulation Model ◽

Tumour Growth

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Cartilage storage at 4 °C with regular culture medium replacement benefits chondrocyte viability of osteochondral grafts in vitro

Cell and Tissue Banking ◽

10.1007/s10561-016-9556-7 ◽

2016 ◽

Vol 17 (3) ◽

pp. 473-479 ◽

Cited By ~ 9

Author(s):

Jianhong Qi ◽

Zunjie Hu ◽

Hongqiang Song ◽

Bin Chen ◽

Di Xie ◽

...

Keyword(s):

Culture Medium ◽

Chondrocyte Viability ◽

Osteochondral Grafts ◽

Regular Culture Medium

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A STELLA simulation model for in vitro dissolution testing of respirable size particles

Scientific Reports ◽

10.1038/s41598-019-55164-0 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Basanth Babu Eedara ◽

Ian G. Tucker ◽

Shyamal C. Das

Keyword(s):

Simulation Model ◽

In Vitro Dissolution ◽

Membrane Thickness ◽

Dissolution Testing ◽

Custom Made ◽

Quality Control Tool ◽

Modeling Software ◽

Fast Dissolution

AbstractIn vitro dissolution testing is a useful quality control tool to discriminate the formulations and to approximate the in vivo drug release profiles. A dissolution apparatus has been custom-made for dissolution testing of dry powder formulations in a small volume of stationary medium (25 μL spread over 4.91 cm2 area i.e. ~50 μm thick). To understand the system and predict the key parameters which influence the dissolution of respirable size particles, a simulation model was constructed using STELLA modeling software. Using this model, the permeation (dissolution followed by diffusion through the membrane) of two anti-tubercular drugs of differing solubilities, moxifloxacin (17.68 ± 0.85 mg mL−1) and ethionamide (0.46 ± 0.02 mg mL−1), from the respirable size particles and their diffusion from a solution were simulated. The simulated permeation profiles of moxifloxacin from solution and respirable size particles were similar, indicating fast dissolution of the particles. However, the simulated permeation profile of ethionamide from respirable size particles showed slower permeation compared to the solution indicating the slow dissolution of the respirable size particles of ethionamide. The sensitivity analysis suggested that increased mucus volume and membrane thickness decreased the permeation of drug. While this model was useful in predicting and distinguishing the dissolution behaviours of respirable size moxifloxacin and ethionamide, further improvement could be made using appropriate initial parameter values obtained by experiments.

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Survival and Germination of Bacillus clausii UBBC07 Spores in in vitro Human Gastrointestinal Tract Simulation Model and Evaluation of Clausin Production

Frontiers in Microbiology ◽

10.3389/fmicb.2020.01010 ◽

2020 ◽

Vol 11 ◽

Author(s):

Jayesh J. Ahire ◽

Megha S. Kashikar ◽

Ratna Sudha Madempudi

Keyword(s):

Gastrointestinal Tract ◽

Simulation Model ◽

Human Gastrointestinal Tract ◽

Bacillus Clausii

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Novel human in vitro vegetation simulation model for infective endocarditis

Apmis ◽

10.1111/apm.13182 ◽

2021 ◽

Author(s):

Franziska A. Schwartz ◽

Lars Christophersen ◽

Anne Sofie Laulund ◽

Rasmus Lundquist ◽

Christian Lerche ◽

...

Keyword(s):

Infective Endocarditis ◽

Simulation Model

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In Vitro Chewing Simulation Model Influence on the Adhesive-Tooth Structure Interface

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.695.77 ◽

2016 ◽

Vol 695 ◽

pp. 77-82

Author(s):

Adriana Caracostea Objelean ◽

Anca Labunet ◽

Laura Silaghi-Dumitrescu ◽

Marioara Moldovan ◽

Sorina Sava ◽

...

Keyword(s):

Simulation Model ◽

Clinical Success ◽

Resin Composite ◽

Posterior Teeth ◽

Tooth Structure ◽

Chewing Simulation ◽

Dental Tissues ◽

Mechanical Cycling ◽

In Vitro Aging

Loss of hard dental tissues of the posterior teeth during caries removal represents an important issue for conservative dentistry. The use of direct dental biomaterials in this case have to satisfy the requirements of the restored area. The studies have shown higher values of chewing forces at the molar teeth level (20-120N) compared to other teeth [1,2]. Thus, for a long-term clinical success the dental biomaterials have to assure a good marginal sealing and a high resistance to thermal and mechanical stresses developed in the lateral zones of the oral cavity [3]. The aim of this study was carried out to assess the effect of an in vitro chewing simulation model on the adhesively-bonded resin composite restorations. Standardized extended proximal cavities were prepared and restored in forty five sound human third molars. Three in vitro aging methods: a chewing simulation model (mechanical cycling and periodontal ligament simulation) (MC+PDL), thermocycling (TC) and distilled water storage (WS), were used to test the marginal sealing behavior of two adhesive techniques (an adhesive-free flowable resin composite and a self-etch all-in-one adhesive system). A weight-controlled dual-axis chewing device (CS-4.2, SD Mechatronik, Germany) was used for mechanical testing (MC) of the samples. Significantly higher marginal leakage values were observed for the chewing simulation model (MC) compared to TC and WS groups (p<0.05). No statistical correlations were found with regard to aging methods for the tracer’s infiltration of the two adhesive techniques. The dual-axis chewing simulator (CS-4.2) due to its facile mechanical adjustment system may be used for different other in vitro aging models or simulated clinical settings.

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Development of Controlled Heterogeneity on a Polymer-Ceramic Hydrogel Scaffold for Osteochondral Repair

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.284-286.607 ◽

2005 ◽

Vol 284-286 ◽

pp. 607-610 ◽

Cited By ~ 4

Author(s):

H.H. Lu ◽

J. Jiang ◽

Ai Tao Tang ◽

C.T. Hung ◽

X.E. Guo

Keyword(s):

Clinical Intervention ◽

Collagen Matrix ◽

Osteochondral Graft ◽

The Novel ◽

Hydrogel Scaffold ◽

Simultaneous Formation ◽

Osteochondral Grafts ◽

Osteochondral Repair ◽

P Content

Due to its intrinsically poor repair potential, injuries to articular cartilage do not heal and clinical intervention is required. Osteochondral grafts may improve healing while promoting integration with host tissue. We report here the development of an osteochondral graft based on a hybrid of a hyrogel and a polymer-bioactive glass composite (PLAGA-BG) microsphere scaffold. This novel osteochondral construct consists of three regions: gel-only, gel/composite interface, and a composite-only-region. The three phases differ in calcium phospate (Ca-P) or BG content. The objective of the current study is to investigate the effects of scaffold composition on chondrocyte response, and to evaluate the effects of co-culture on osteoblasts and chondrocyte growh and differentiation on the hybrid scaffold. The PLAGA-BG microsphere scaffold supported the growth of chondrocytes and initial results indicate that in the presence of BG, chondrocyte-mediated mineralization may be stimulated. Co-culture of osteoblasts and chondrocytes on the multi-phased scaffold with varied Ca-P content facilitated the formation of multiple matrix zones: a GAGrich chondrocyte region, an interfacial matrix rich in GAG+collagen, and a mineralized collagen matrix with osteoblasts. In summary, chondrocyte response has been optimized as a function of scaffold composition and the novel osteochondral graft has the potential to support the simultaneous formation of multiple types of tissue in vitro.

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