A Comprehensive Study of Osteogenic Calcium Phosphate Silicate Cement: Material Characterization and In Vitro/In Vivo Testing

2015 ◽  
Vol 5 (4) ◽  
pp. 457-466 ◽  
Author(s):  
Tianxing Gong ◽  
Zhiqin Wang ◽  
Yixi Zhang ◽  
Yubiao Zhang ◽  
Mingxiao Hou ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Material Characterization ◽  
Cement Material ◽  
Phosphate Silicate ◽  
In Vivo Testing ◽  
Comprehensive Study

scholarly journals Chitosan Scaffolds Containing Calcium Phosphate Salts and rhBMP-2: In Vitro and In Vivo Testing for Bone Tissue Regeneration

PLoS ONE ◽  
2014 ◽  
Vol 9 (2) ◽  
pp. e87149 ◽  
Author(s):  
Rodrigo Guzmán ◽  
Stefania Nardecchia ◽  
María C. Gutiérrez ◽  
María Luisa Ferrer ◽  
Viviana Ramos ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Tissue ◽  
Tissue Regeneration ◽  
Bone Tissue Regeneration ◽  
In Vivo Testing ◽  
Chitosan Scaffolds ◽  
Phosphate Salts

Biomimetic Organic-Inorganic Nanocomposite Coatings for Titanium Implants. II. Biological "In Vitro" and "In Vivo" Characterization

2007 ◽  
Vol 330-332 ◽  
pp. 401-404 ◽  
Author(s):  
M. Dutour Sikirić ◽  
Rene Elkaim ◽  
S. Lamolle ◽  
H.J. Ronold ◽  
S.P. Lyngstadass ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Organic Matrix ◽  
Titanium Implants ◽  
Nanocomposite Coatings ◽  
In Vivo Testing ◽  
In Vivo Characterization

Biological mineralization proceeds within an organic matrix and is induced and controlled by extracellular, highly acidic matrix macromolecules. Our group has recently prepared organic-inorganic nanocomposite coatings by a strategy that closely mimics these processes. The strategy involves depositing a matrix of polyelectrolyte multilayers (PE MLs), alternating with layers of amorphous calcium phosphate (ACP) particles, then "in situ" growing nanosized apatite crystals within that matrix [1, 2]. Here we describe the results of biological "in vitro" and "in vivo" testing of these materials.

Aspiration Revisited: Prospective Evaluation of a Physiologically Pressurized Model With Animal Correlation and Broader Applicability to Filler Complications

2021 ◽  
Author(s):  
Hyoung-Jin Moon ◽  
Won Lee ◽  
Ji-Soo Kim ◽  
Eun-Jung Yang ◽  
Hema Sundaram
Keyword(s):  
Normal Saline ◽  
False Negative ◽  
Vascular Complications ◽  
Filler Injection ◽  
Negative Results ◽  
Needle Position ◽  
False Negative Results ◽  
In Vivo Testing

Abstract Background Aspiration testing before filler injection is controversial. Some believe that aspiration can help prevent inadvertent intravascular injection, while others cite false-negative results and question its value given that the needle position always changes somewhat during injection procedures. Objectives To test the relation of false-negative results to the viscosity of the material within the needle lumen and determine whether a less viscous material within the needle lumen could decrease the incidence of false-negative results. Methods In vitro aspiration tests were performed using 30-G and 27-G needle gauges, two cross-linked hyaluronic acid fillers, normal saline bags pressurized at 140 and 10 mmHg to mimic human arterial and venous pressures, and three needle lumen conditions (normal saline, air, and filler). Testing was repeated three times under each study condition (72 tests in total). For in vivo correlation, aspiration tests were performed on femoral arteries and central auricular veins in three rabbits (4–5 aspirations per site, 48 tests in total). Results In vitro and in vivo testing using 30-G needles containing filler both showed false-negative results on aspiration testing. In vitro and in vivo testing using needles containing saline or air showed positive findings. Conclusions False-negative results from aspiration testing may be reduced by pre-filling the needle lumen with saline rather than a filler. The pressurized system may help overcome challenges of animal models with intravascular pressures significantly different from those of humans. The adaptability of this system to mimic various vessel pressures may facilitate physiologically relevant studies of vascular complications.

scholarly journals Effective decellularisation of human saphenous veins for biocompatible arterial tissue engineering applications: Bench optimisation and feasibility in vivo testing

2021 ◽  
Vol 12 ◽  
pp. 204173142098752
Author(s):  
Nadiah S Sulaiman ◽  
Andrew R Bond ◽  
Vito D Bruno ◽  
John Joseph ◽  
Jason L Johnson ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Mechanical Strength ◽  
Vascular Tissue ◽  
Sodium Dodecyl ◽  
Host Cells ◽  
Replacement Model ◽  
In Vivo Testing ◽  
Vascular Scaffolds

Human saphenous vein (hSV) and synthetic grafts are commonly used conduits in vascular grafting, despite high failure rates. Decellularising hSVs (D-hSVs) to produce vascular scaffolds might be an effective alternative. We assessed the effectiveness of a detergent-based method using 0% to 1% sodium dodecyl sulphate (SDS) to decellularise hSV. Decellularisation effectiveness was measured in vitro by nuclear counting, DNA content, residual cell viability, extracellular matrix integrity and mechanical strength. Cytotoxicity was assessed on human and porcine cells. The most effective SDS concentration was used to prepare D-hSV grafts that underwent preliminary in vivo testing using a porcine carotid artery replacement model. Effective decellularisation was achieved with 0.01% SDS, and D-hSVs were biocompatible after seeding. In vivo xeno-transplantation confirmed excellent mechanical strength and biocompatibility with recruitment of host cells without mechanical failure, and a 50% patency rate at 4-weeks. We have developed a simple biocompatible methodology to effectively decellularise hSVs. This could enhance vascular tissue engineering toward future clinical applications.

scholarly journals DDEL-12. NANOPARTICLE DELIVERY OF DOXORUBICIN FOR THE TREATMENT OF DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG)

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii286-iii286
Author(s):  
Caitlin Ung ◽  
Maria Tsoli ◽  
Jie Liu ◽  
Domenico Cassano ◽  
Dannielle Upton ◽  
...  
Keyword(s):  
Treatment Strategies ◽  
Pediatric Brain Tumors ◽  
Diffuse Intrinsic Pontine Glioma ◽  
Confocal Imaging ◽  
Cell Content ◽  
Potent Effect ◽  
Orthotopic Mouse Model ◽  
In Vivo Testing

Abstract DIPGs are the most aggressive pediatric brain tumors. Currently, the only treatment is irradiation but due to its palliative nature patients die within 12 months. Effective delivery of chemotherapy across the blood-brain barrier (BBB) has been a key challenge for the eradication of this disease. We have developed a novel gold nanoparticle functionalised with human serum albumin (Au-NP, 98.8 ±19 nm) for the delivery of doxorubicin. In this study, we evaluated the cytotoxic efficacy of doxorubicin delivered through gold nanoparticles (Au-NP-Dox). We found that DIPG neurospheres were equally sensitive to doxorubicin and Au-NP-Dox (at equimolar concentration) by alamar blue assay. Colony formation assays demonstrated a significantly more potent effect of Au-NP-Dox compared to doxorubicin alone, while the Au-NP had no effect. Furthermore, western blot analysis indicated increased apoptotic markers cleaved Parp, caspase 3/7 and phosphorylated H2AX in Au-NP-Dox treated DIPG neurospheres. Live cell content and confocal imaging demonstrated significantly higher uptake of Au-NP-Dox compared to doxorubicin alone. Treatment of a DIPG orthotopic mouse model with Au-NP-Dox showed no signs of toxicity with stable weights being maintained during treatment. However, in contrast to the above in vitro findings the in vivo study showed no anti-tumor effect possibly due to poor penetration of Au-NP-Dox into the brain. We are currently evaluating whether efficacy can be improved using measures to open the BBB transiently. This study highlights the need for rigorous in vivo testing of new treatment strategies before clinical translation to reduce the risk of administration of ineffective treatments.

In vitro and in vivo testing and correlation for oral controlled/ modified release dosage forms. report of the 2nd workshop held December 1988, Washington, DC. U.S.A.

1990 ◽  
Vol 14 (1) ◽  
pp. 95-106 ◽  
Author(s):  
Jerome P. Skelly ◽  
Gordon L. Amidon ◽  
William H. Barr ◽  
Leslie Z. Benet ◽  
James E. Carter ◽  
...  
Keyword(s):  
Dosage Forms ◽  
Washington Dc ◽  
Modified Release ◽  
In Vivo Testing

scholarly journals Coagulation under Mild Hypothermia Assessed by Thromboelastometry

2021 ◽  
pp. 1-7
Author(s):  
Tobias Nitschke ◽  
Philipp Groene ◽  
Alice-Christin Acevedo ◽  
Tobias Kammerer ◽  
Simon T. Schäfer
Keyword(s):  
Mild Hypothermia ◽  
Onset Time ◽  
Rotational Thromboelastometry ◽  
Lysis Time ◽  
Sample Data ◽  
In Vivo Testing ◽  
Fibrinolytic Capacity ◽  
Clot Formation Time

<b><i>Introduction:</i></b> While previous studies have shown a significant impact of extreme hypo- and hyperthermia on coagulation, effects of much more frequently occurring perioperative mild hypothermia are largely unknown. This study therefore aimed to analyze the effects of mild hypothermia using rotational thromboelastometry in vitro. <b><i>Materials and Methods:</i></b> Twelve healthy volunteers were included in this study. Standard thromboelastometric tests (EXTEM, INTEM, FIBTEM) were used to evaluate coagulation in vitro at 39, 37, 35.5, 35, and 33°C. Beyond standard thromboelastometric tests, we also evaluated the effects of mild hypothermia on the TPA-test (ClotPro, Enicor GmbH, Munich, Germany), a new test which aims to detect fibrinolytic capacity by adding tissue plasminogen activator to the sample. Data are presented as the median with 25/75th percentiles. <b><i>Results:</i></b> Extrinsically activated coagulation (measured by EXTEM) showed a significant increase in clot formation time (CFT; 37°C: 90 s [81/105] vs. 35°C: 109 s [99/126]; <i>p</i> = 0.0002), while maximum clot firmness (MCF) was not significantly reduced. Intrinsically activated coagulation (measured by INTEM) also showed a significant increase in CFT (37°C: 80 s [72/88] vs. 35°C: 94 s [86/109]; <i>p</i> = 0.0002) without significant effects on MCF. Mild hypothermia significantly increased both the lysis onset time (136 s [132/151; 37°C] vs. 162 s [141/228; 35°C], <i>p</i> = 0.0223) and lysis time (208 s [184/297; 37°C] vs. 249 s [215/358; 35°C]; <i>p</i> = 0.0259). <b><i>Conclusion:</i></b> This demonstrates that even under mild hypothermia coagulation is significantly altered in vitro. Perioperative temperature monitoring and management are greatly important and can help to prevent mild hypothermia and its adverse effects. Further investigation and in vivo testing of coagulation under mild hypothermia is needed.

Calcium Phosphate Coating on Blast-Treated Titanium Implants by RF Magnetron Sputtering

2009 ◽  
Vol 631-632 ◽  
pp. 211-216 ◽  
Author(s):  
Kyosuke Ueda ◽  
Takayuki Narushima ◽  
Takashi Goto ◽  
T. Katsube ◽  
Hironobu Nakagawa ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Magnetron Sputtering ◽  
Bonding Strength ◽  
Rf Magnetron Sputtering ◽  
Titanium Implants ◽  
Calcium Phosphate Coating ◽  
Phosphate Coating ◽  
Coating Films

Calcium phosphate coating films were fabricated on Ti-6Al-4V plates and screw-type implants with a blast-treated surface using radiofrequency (RF) magnetron sputtering and were evaluated in vitro and in vivo. Amorphous calcium phosphate (ACP) and oxyapatite (OAp) films obtained in this study could cover the blast-treated substrate very efficiently, maintaining the surface roughness. For the in vitro evaluations of the calcium phosphate coating films, bonding strength and alkaline phosphatase (ALP) activity were examined. The bonding strength of the coating films to a blast-treated substrate exceeded 60 MPa, independent of film phases except for the film after post-heat-treatment in silica ampoule. When compared with an uncoated substrate, the increase in the ALP activity of osteoblastic SaOS-2 cells on a calcium phosphate coated substrate was confirmed by a cell culture test. The removal torque of screw-type Ti-6Al-4V implants with a blast-treated surface from the femur of Japanese white rabbit increased with the duration of implantation and it was statistically improved by coating an ACP film 2 weeks after implantation. The in vitro and in vivo studies suggested that the application of the sputtered ACP film as a coating on titanium implants was effective in improving their biocompatibility with bones.

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