scholarly journals Integration of 3D Printed and Micropatterned Polycaprolactone Scaffolds for Guidance of Oriented Collagenous Tissue Formation In Vivo

2016 ◽  
Vol 5 (6) ◽  
pp. 676-687 ◽  
Author(s):  
Sophia P. Pilipchuk ◽  
Alberto Monje ◽  
Yizu Jiao ◽  
Jie Hao ◽  
Laura Kruger ◽  
...  
Keyword(s):  
Tissue Formation ◽  
Collagenous Tissue ◽  
3D Printed

Design, Fabrication, and Accuracy of a Novel Noncovering Lock-Mechanism Bilateral Patient-Specific Drill Guide Template for Nondeformed and Deformed Thoracic Spines

2021 ◽  
pp. 155633162199633
Author(s):  
Mehran Ashouri-Sanjani ◽  
Shima Mohammadi-Moghadam ◽  
Parisa Azimi ◽  
Navid Arjmand
Keyword(s):  
Thoracic Spine ◽  
Sagittal Plane ◽  
Ct Scanning ◽  
Entry Point ◽  
In Vivo Studies ◽  
Patient Specific ◽  
Plane Angle ◽  
Severe Scoliosis ◽  
3D Printed

Background: Pedicle screw (PS) placement has been widely used in fusion surgeries on the thoracic spine. Achieving cost-effective yet accurate placements through nonradiation techniques remains challenging. Questions/Purposes: Novel noncovering lock-mechanism bilateral vertebra-specific drill guides for PS placement were designed/fabricated, and their accuracy for both nondeformed and deformed thoracic spines was tested. Methods: One nondeformed and 1 severe scoliosis human thoracic spine underwent computed tomographic (CT) scanning, and 2 identical proportions of each were 3-dimensional (3D) printed. Pedicle-specific optimal (no perforation) drilling trajectories were determined on the CT images based on the entry point/orientation/diameter/length of each PS. Vertebra-specific templates were designed and 3D printed, assuring minimal yet firm contacts with the vertebrae through a noncovering lock mechanism. One model of each patient was drilled using the freehand and one using the template guides (96 pedicle drillings). Postoperative CT scans from the models with the inserted PSs were obtained and superimposed on the preoperative planned models to evaluate deviations of the PSs. Results: All templates fitted their corresponding vertebra during the simulated operations. As compared with the freehand approach, PS placement deviations from their preplanned positions were significantly reduced: for the nonscoliosis model, from 2.4 to 0.9 mm for the entry point, 5.0° to 3.3° for the transverse plane angle, 7.1° to 2.2° for the sagittal plane angle, and 8.5° to 4.1° for the 3D angle, improving the success rate from 71.7% to 93.5%. Conclusions: These guides are valuable, as the accurate PS trajectory could be customized preoperatively to match the patients’ unique anatomy. In vivo studies will be required to validate this approach.

scholarly journals Fabrication of 3D-Printed Interpenetrating Hydrogel Scaffolds for Promoting Chondrogenic Differentiation

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2146
Author(s):  
Jian Guan ◽  
Fu-zhen Yuan ◽  
Zi-mu Mao ◽  
Hai-lin Zhu ◽  
Lin Lin ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Elastic Modulus ◽  
Chondrogenic Differentiation ◽  
Marker Genes ◽  
Self Healing ◽  
Polyethylene Glycol Diacrylate ◽  
3D Microenvironment ◽  
3D Printed

The limited self-healing ability of cartilage necessitates the application of alternative tissue engineering strategies for repairing the damaged tissue and restoring its normal function. Compared to conventional tissue engineering strategies, three-dimensional (3D) printing offers a greater potential for developing tissue-engineered scaffolds. Herein, we prepared a novel photocrosslinked printable cartilage ink comprising of polyethylene glycol diacrylate (PEGDA), gelatin methacryloyl (GelMA), and chondroitin sulfate methacrylate (CSMA). The PEGDA-GelMA-CSMA scaffolds possessed favorable compressive elastic modulus and degradation rate. In vitro experiments showed good adhesion, proliferation, and F-actin and chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) on the scaffolds. When the CSMA concentration was increased, the compressive elastic modulus, GAG production, and expression of F-actin and cartilage-specific genes (COL2, ACAN, SOX9, PRG4) were significantly improved while the osteogenic marker genes of COL1 and ALP were decreased. The findings of the study indicate that the 3D-printed PEGDA-GelMA-CSMA scaffolds possessed not only adequate mechanical strength but also maintained a suitable 3D microenvironment for differentiation, proliferation, and extracellular matrix production of BMSCs, which suggested this customizable 3D-printed PEGDA-GelMA-CSMA scaffold may have great potential for cartilage repair and regeneration in vivo.

scholarly journals Thrombus Imaging Using 3D Printed Middle Cerebral Artery Model and Preclinical Imaging Techniques: Application to Thrombus Targeting and Thrombolytic Studies

Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1207
Author(s):  
Andrea Vítečková Wünschová ◽  
Adam Novobilský ◽  
Jana Hložková ◽  
Peter Scheer ◽  
Hana Petroková ◽  
...  
Keyword(s):  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Imaging Techniques ◽  
Barium Sulphate ◽  
Flow Conditions ◽  
Preclinical Imaging ◽  
Blood Clots ◽  
3D Printed

Diseases with the highest burden for society such as stroke, myocardial infarction, pulmonary embolism, and others are due to blood clots. Preclinical and clinical techniques to study blood clots are important tools for translational research of new diagnostic and therapeutic modalities that target blood clots. In this study, we employed a three-dimensional (3D) printed middle cerebral artery model to image clots under flow conditions using preclinical imaging techniques including fluorescent whole-body imaging, magnetic resonance imaging (MRI), and computed X-ray microtomography (microCT). Both liposome-based, fibrin-targeted, and non-targeted contrast agents were proven to provide a sufficient signal for clot imaging within the model under flow conditions. The application of the model for clot targeting studies and thrombolytic studies using preclinical imaging techniques is shown here. For the first time, a novel method of thrombus labeling utilizing barium sulphate (Micropaque®) is presented here as an example of successfully employed contrast agents for in vitro experiments evaluating the time-course of thrombolysis and thus the efficacy of a thrombolytic drug, recombinant tissue plasminogen activator (rtPA). Finally, the proof-of-concept of in vivo clot imaging in a middle cerebral artery occlusion (MCAO) rat model using barium sulphate-labelled clots is presented, confirming the great potential of such an approach to make experiments comparable between in vitro and in vivo models, finally leading to a reduction in animals needed.

In Vitro Degradation of β-TCP/PLLA Scaffolds with Different Proportions of β-TCP

2007 ◽  
Vol 336-338 ◽  
pp. 1545-1548
Author(s):  
Lin Luo ◽  
Guang Fu Yin ◽  
Yun Zhang ◽  
Ya Dong Yao ◽  
Wei Zhong Yang ◽  
...  
Keyword(s):  
Degradation Rate ◽  
Porous Scaffolds ◽  
Carbonate Apatite ◽  
Tissue Formation ◽  
Cellular Attachment ◽  
Biodegradable Scaffolds ◽  
Scaffold Structure ◽  
Mechanical Strengths

Porous biodegradable scaffolds are widely used in bone tissue engineering to provide temporary templates for cellular attachment and matrix synthesis. Ideally, the degradation rate in vivo may be similar or slightly less than that of tissue formation, allowing for the maintenance of the scaffold structure and the mechanical support during early stages of tissue formation. Eventually, the 3-D spaces occupied by the porous scaffolds will be replaced by newly formed tissue. In this work, β-tricalcium phosphate/Poly-L lactide (β-TCP/PLLA) scaffolds with different proportions of β-TCP to PLLA were investigated. The effects of β-TCP proportions on degradation rate and mechanical strengths of the scaffolds were evaluated in simulated body fluid (SBF) at 37°C up to 42 days. Results show that: different proportions of β-TCP to PLLA have significant influence on degradation behaviors of the scaffolds, and mechanical strengths of the scaffolds with weight proportion of β-TCP to PLLA being 2 to 1 are much higher than those of the others during the degradation period. And in this period, the scaffolds biodegrade slowly, and Hydroxyl Carbonate Apatite (HCA) forms in the surface of the material.

In Vivo Bone Tissue Formation Induced by Caclium Phosphate Paste Composite with Demineralized Bone Matrix

2007 ◽  
Vol 330-332 ◽  
pp. 1091-1094
Author(s):  
H. Kim ◽  
M. Park ◽  
Su Young Lee ◽  
Kang Yong Lee ◽  
Hyun Min Kim ◽  
...  
Keyword(s):  
Animal Model ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Demineralized Bone Matrix ◽  
Bone Matrix ◽  
Marker Gene ◽  
Tissue Formation ◽  
Bone Tissue Formation ◽  
Demineralized Bone

Demineralized bone matrix (DBM)-calcium phosphate cement (CPC) composites were subjected to cellular test of osteogenic potentials and implantation in animal model. The expression of osteogenic marker gene from mouse preosteoblast cell line MC3T3-E1 adhered to the DBM-CPC composite was much higher than plain CPC. In addition, the DBM-CPC composite implanted nude mice revealed osteoinduction between the implanted composite and adjacent tissues, whereas the plain CPC induced osteoconduction.

scholarly journals In Vivo Evaluation of 3D-Printed Polycaprolactone Scaffold Implantation Combined with β-TCP Powder for Alveolar Bone Augmentation in a Beagle Defect Model

Materials ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 238 ◽  
Author(s):  
Su Park ◽  
Hyo-Jung Lee ◽  
Keun-Suh Kim ◽  
Sang Lee ◽  
Jung-Tae Lee ◽  
...  
Keyword(s):  
Alveolar Bone ◽  
Bone Augmentation ◽  
Defect Model ◽  
In Vivo Evaluation ◽  
3D Printed

Abstract 17070: Engineering a Novel Ex Vivo Heart Simulator for Biomechanical Analysis of the Aortomitral Junction

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Matthew H Park ◽  
Annabel Imbrie-moore ◽  
Yuanjia Zhu ◽  
Hanjay Wang ◽  
Michael J Paulsen ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Ex Vivo ◽  
Clinical Care ◽  
Biomechanical Analysis ◽  
Future Experimentation ◽  
3D Printed ◽  
Biomechanical Changes ◽  
Predictive Risk ◽  
Future Work

Introduction: Advances in ex vivo heart simulation have enabled the study of valvular biomechanics, disease pathologies, and repair strategies. However, these simulators test the valves in isolation, which does not fully replicate in vivo physiology. We hypothesize that by engineering a simulator that preserves the aortomitral junction, we can better recreate pathophysiologies such as systolic anterior motion (SAM). Here, we present a new heart simulator that preserves and manipulates the native aortomitral physiology. Methods: Our simulator is comprised of three subsystems: the ventricular chamber, atrial chamber, and aortic chamber (Fig A, B). The heart is excised at the apex to preserve the papillary muscles, and the left ventricle, atrial cuff, and aorta are fixed to their respective chambers via hemostatic suturing to 3D-printed elastomeric rings. The chambers are equipped with pressure and flow sensors, and a linear piston pump generates physiologic pressures and flows. The atrial and aortic chambers are mounted on 5-degree-of-freedom arms. To demonstrate system function, we manipulated the aortomitral angle and measured aortic cardiac output. Results: In our testing, we evaluated two unique configurations of an explanted porcine heart, of which the aortomitral angles spanned the SAM predictive risk threshold of <120° (Fig C, D). From the flow readings, we measured a 36% reduction in aortic cardiac output upon decreasing the aortomitral angle by 25°. Conclusions: This work highlights the design and development of an ex vivo heart simulator capable of modeling native aortomitral physiology. Our results point to a clear direction for future experimentation, particularly evaluating the biomechanical changes of the heart based on the aortomitral angle. Future work will utilize this platform to create new models and repair techniques to ultimately improve clinical care of valvular pathologies.

PO-1632 3D-Printed template to perform in vivo dosimetry in breast high dose rate brachytherapy treatments

2021 ◽  
Vol 161 ◽  
pp. S1353-S1354
Author(s):  
M. Gutiérrez Ruiz ◽  
R. Astudillo Olalla ◽  
A.L. Rivero ◽  
P. érez ◽  
J.T. Anchuelo Latorre ◽  
...  
Keyword(s):  
Dose Rate ◽  
High Dose Rate ◽  
In Vivo Dosimetry ◽  
High Dose ◽  
High Dose Rate Brachytherapy ◽  
3D Printed
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