scholarly journals In-vitro cell treatment with focused shockwaves—influence of the experimental setup on the sound field and biological reaction

2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Kristin Dietz-Laursonn ◽  
Rainer Beckmann ◽  
Siegfried Ginter ◽  
Klaus Radermacher ◽  
Matías de la Fuente
Keyword(s):  
Sound Field ◽  
Experimental Setup ◽  
Biological Reaction

scholarly journals Water Jet Applicator for Interface Tissue Removal in Minimally Invasive Hip Refixation: Testing the Principle and Design of Prototype

2019 ◽  
Vol 13 (2) ◽  
Author(s):  
Gert Kraaij ◽  
Arjo J. Loeve ◽  
Jenny Dankelman ◽  
Rob G. H. H. Nelissen ◽  
Edward R. Valstar
Keyword(s):  
Theoretical Analysis ◽  
Minimally Invasive ◽  
Water Pressure ◽  
Minimal Invasive ◽  
Outer Diameter ◽  
Experimental Setup ◽  
Technical Requirements ◽  
Tissue Removal ◽  
Further Development

Mechanical loosening of implants is in the majority accompanied with a periprosthetic interface membrane, which has to be removed during revision surgery. The same is true if a minimal invasive (percutaneous) refixation of a loose implant is done. We describe the requirements for a waterjet applicator for interface tissue removal for this percutaneous hip refixation technique. The technical requirements were either obtained from a literature review, a theoretical analysis, or by experimental setup. Based on the requirements, a waterjet applicator is designed which is basically a flexible tube (outer diameter 3 mm) with two channels. One channel for the water supply (diameter 0.9 mm) and one for suction to evacuate water and morcellated interface tissue from the periprosthetic cavity. The applicator has a rigid tip (length 6 mm), which directs the water flow to create two waterjets (diameter 0.2 mm), both focused into the suction channel. The functionality of this new applicator is demonstrated by testing a prototype of the applicator tip in an in vitro experimental setup. This testing has shown that the designed applicator for interface tissue removal will eliminate the risk of water pressure buildup; the ejected water was immediately evacuated from the periprosthetic cavity. Blocking of the suction opening was prevented because the jets cut through interface tissue that gets in front of the suction channel. Although further development of the water applicator is necessary, the presented design of the applicator is suitable for interface tissue removal in a minimally invasive hip refixation procedure.

One Dimensional Experimental Setup to Study the Heating of Nanoparticle Laden Systems

2010 ◽  
Author(s):  
Zhenpeng Qin ◽  
John C. Bischof
Keyword(s):  
Small Volume ◽  
Laser Energy ◽  
Special Kind ◽  
Gold Nanoshells ◽  
Experimental Setup ◽  
Heat Absorption ◽  
One Dimensional ◽  
Lumped Models

Intensive efforts have been put into the use of gold nanoparticles (GNPs) for the enhancement of hyperthermia using laser in recent years since the groundbreaking work of Hirsh et al.(1) using gold nanoshells (GNS). Both in vitro (2), and in vivo (3) studies show promising results. For example, GNS, a special kind of GNP, are being manufactured and are in clinical trials (Nanospectra Bioscience, Inc). While the data is compelling, unfortunately the fundamentals of GNP heating are not entirely understood. For example, there are large discrepancies in the experimentally measured photothermal efficiency of GNPs (4, 5). Furthermore, lumped models of GNP heating in solution, by using small volume of GNP solution (4, 5), or stirring the solution (6), neglecting the variation of heat absorption throughout a system require improvement. In reality, the GNPs will attenuate the laser beam as it passes through the GNP host medium. GNPs at different locations will absorb different amount of laser energy and hence have different heat generation.

Biological Reaction to Electrically Polarized Hydroxyapatite

2000 ◽  
Vol 662 ◽  
Author(s):  
Tomoko Sakai ◽  
Masato Ueshima ◽  
Sadao Morita ◽  
Satoshi Nakamura ◽  
Kimihiro Yamashita
Keyword(s):  
Bone Formation ◽  
Body Fluid ◽  
Bone Defects ◽  
New Bone Formation ◽  
In Vitro Experiment ◽  
In Vivo Experiments ◽  
Biological Reaction ◽  
Positively Charged

AbstractWe have studied the polarized hydroxyapatite (HAp) whose surface was negatively or positively charged. In this study, we assessed the interfaces in vitro and in vivo periodically. As in vitro experiment, samples were immersed in simulated body fluid for 7 days and the surface was examined by scanning electron microscope (SEM). As in vivo experiments, cortical bone defects were created on the femoral trochanters and the condyles of the six Japanese white rabbits and the samples were implanted. The rabbits were sacrificed at 1, 2 and 4 W after the operation to analyze the surfaces by the SEM and the optical microscopy. In this study, a new thick apatite layer was formed on the negatively charged surface (N-surface) after 1week immersion in SBF in vitro. Besides, significant new bone formation was found at 2 weeks after the operation on N-surface in vivo, which was earlier than positively charged or non-polarized HAp surface. From this study negatively charged HAp surface by polarization accelerated the HAp crystal growth or the new bone formation. Thus, this N-surface will be promising for earlier fixation of the prosthesis or better recovery of the bone defect.

Self-organization mechanism in a bone-like hydroxyapatite/collagen nanocomposite synthesized in vitro and its biological reaction in vivo

Biomaterials ◽  
2001 ◽  
Vol 22 (13) ◽  
pp. 1705-1711 ◽  
Author(s):  
Masanori Kikuchi ◽  
Soichiro Itoh ◽  
Shizuko Ichinose ◽  
Kenichi Shinomiya ◽  
Junzo Tanaka
Keyword(s):  
Self Organization ◽  
Biological Reaction ◽  
Organization Mechanism

scholarly journals Torque Loss After Miniscrew Placement: An In-Vitro Study Followed by a Clinical Trial

2016 ◽  
Vol 10 (1) ◽  
pp. 251-260 ◽  
Author(s):  
Marco Migliorati ◽  
Sara Drago ◽  
Fabrizio Barberis ◽  
Irene Schiavetti ◽  
Domenico Dalessandri ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Insertion Time ◽  
Controlled Environment ◽  
Insertion Torque ◽  
Experimental Setup ◽  
Percentage Difference ◽  
Torque Loss ◽  
Torque Values

To evaluate torque loss a week after insertion, both in an in vivo and an in vitro experimental setup were designed. In the in vivo setup a total of 29 miniscrews were placed in 20 patients who underwent orthodontic treatment. Maximum insertion torque (MIT) was evaluated at insertion time (T1). A week later, insertion torque was measured again by applying a quarter turn (T2); no load was applied on the screw during the first week. In the in vitro setup a total of 20 miniscrews were placed in pig rib bone samples. MIT was evaluated at insertion time (T1). Bone samples were kept in saline solution and controlled environment for a week during which the solution was refreshed every day. Afterwards, torque was measured again by applying a quarter turn (T2). The comparison of MIT over time was done calculating the percentage difference of the torque values between pre- and post-treatment and using the parametric two independent samples t-test or the non-parametric Mann–Whitney test. After a week unloaded miniscrews showed a mean loss of rotational torque of 36.3% and 40.9% in in vitro and in in vivo conditions, respectively. No statistical differences were found between the two different setups. Torque loss was observed after the first week in both study models; in vitro experimental setup provided a reliable study model for studying torque variation during the first week after insertion.

scholarly journals Catheter tip distensibility substantially influences the aspiration force of thrombectomy devices

2021 ◽  
pp. neurintsurg-2021-017487
Author(s):  
Jiahui Li ◽  
Oscar Castaño ◽  
Alejandro Tomasello ◽  
Marta de Dios Lascuevas ◽  
Pere Canals ◽  
...  
Keyword(s):  
Relative Difference ◽  
Experimental Setup ◽  
Section Area ◽  
Wide Range ◽  
Device Efficiency ◽  
First Pass ◽  
Catheter Tip ◽  
3D Printed ◽  
Inner Diameter

BackgroundA direct aspiration first pass thrombectomy (ADAPT) is a fast-growing technique for which a broad catalog of catheters that provide a wide range of aspiration forces can be used. We aimed to characterize different catheters' aspiration performance on stiff clots in an in vitro vascular model. We hypothesized that labeled catheter inner diameter (labeled-ID) is not the only parameter that affects the aspiration force (asp-F) and that thrombus–catheter tip interaction and distensibility also play a major role.MethodsWe designed an experimental setup consisting of a 3D-printed carotid artery immersed in a water deposit. We measured asp-F and distensibility of catheter tips when performing ADAPT on a stiff clot analog larger than catheter labeled-ID. Correlations between asp-F, catheter ID, and tip distensibility were statistically assessed.ResultsExperimental asp-F and catheter labeled-ID were correlated (r=0.9601; P<0.01). The relative difference between experimental and theoretical asp-F (obtained by the product of the tip’s section area by the vacuum pressure) correlated with tip’s distensibility (r=0.9050; P<0.01), evidencing that ADAPT performance is highly influenced by catheter tip shape-adaptability to the clot and that the effective ID (eff-ID) may differ from the labeled-ID specified by manufacturers. Eff-ID showed the highest correlation with experimental asp-F (r=0.9944; P<0.01), confirming that eff-ID rather than labeled-ID should be considered to better estimate the device efficiency.ConclusionsCatheter tip distensibility can induce a significant impact on ADAPT performance when retrieving a stiff clot larger than the device ID. Our findings might contribute to optimizing thrombectomy strategies and the design of novel aspiration catheters.

Does surface coating of metallic nanoparticles modulate their interference with in vitro assays?

RSC Advances ◽  
2015 ◽  
Vol 5 (87) ◽  
pp. 70787-70807 ◽  
Author(s):  
Ivana Vinković Vrček ◽  
Ivan Pavičić ◽  
Tea Crnković ◽  
Darija Jurašin ◽  
Michal Babič ◽  
...  
Keyword(s):  
Surface Coating ◽  
Metallic Nanoparticles ◽  
Test System ◽  
In Vitro Assays ◽  
Experimental Setup ◽  
Metal Core ◽  
Core Surface ◽  
System P

Experimental setup for in vitro evaluation of metallic nanoparticles where interferences depend on metal core, surface coating, and the test system.

scholarly journals Construction of a novel microfluidic experimental setup for testing recent glaucoma drainage devices

2019 ◽  
Vol 5 (1) ◽  
pp. 219-222
Author(s):  
Emre Kara ◽  
Ahmet İhsan Kutlar ◽  
Kıvanç Güngör
Keyword(s):  
Flow Behavior ◽  
Pressure Sensors ◽  
Control Unit ◽  
Pressure Control ◽  
World Health ◽  
Experimental Setup ◽  
Great Effort ◽  
Glaucoma Drainage Devices

AbstractGlaucoma is an eye disorder in which the optic nerve is damaged over time due to a sustained elevation of the intraocular pressure (IOP). Being the second leading cause of blindness according to the reports of the World Health Organization, glaucoma is not only a serious ocular disease that threatens individuals, but also a community health problem. In recent years, great improvement has been achieved in the technology of implants used in the treatment of the disease. Despite the great effort dedicated to the design and implementation of the glaucoma drainage devices (GDD), they still have unsolved problems and weaknesses. Most of the currently employed GDDs are very simple and have major problems such as reversed flow, choking and a coarse interval of pressure control. Experiments must be devised to investigate the flow behavior inside these devices. In this study, an accurate microfluidics experimental setup is constructed to analyze and characterize the in-vitro performance of actively employed GDDs on the glaucoma treatment. Proposed setup includes a pressurized fluid reservoir, ELVEFLOW microfluidics flow rate measurement/control unit, microfluidics flow/pressure sensors, and data analysis system. In the setup, more precise measurements than experimental setups in literature is planned to be provided. It is estimated that the results showing consistency with in-vivo measurements will be obtained, behavior of the fluid passing through the GDDs will be observed and issues with design flaws will be addressed.

Preliminary Study on the Biocompatibility of Calcium Phosphate Bone Cement Containing N,O-Carboxymethyl Chitosan

2007 ◽  
Vol 330-332 ◽  
pp. 807-810
Author(s):  
Qi Huang ◽  
Feng Cao ◽  
Dong Xu Li
Keyword(s):  
Calcium Phosphate ◽  
Bone Cement ◽  
Normal Saline ◽  
Carboxymethyl Chitosan ◽  
In Vitro Tests ◽  
Calcium Phosphate Bone Cement ◽  
Biological Reaction ◽  
Good Biocompatibility ◽  
Preliminary Study

N,O-carboxymethyl chitosan (CMCTS) was added in Calcium phosphate bone cement (CPC). A preliminary study was carried out in order to evaluate the biocompatibility of CPC containing CMCTS. In vitro tests were done using extract liquid from normal saline. The result showed that the biological reaction complied with standards of GB/16886 and the composite might have good biocompatibility.

Sign in / Sign up

Export Citation Format

Share Document