scholarly journals In vitro investigation of the impact of remaining tooth structure on the tensile failure loads of overdenture copings

2019 ◽  
pp. 0-0
Author(s):  
A Fotiou ◽  
SN Kamalakidis ◽  
AL Pissiotis ◽  
K Michalakis
Keyword(s):  
Tensile Failure ◽  
Tooth Structure ◽  
In Vitro Investigation ◽  
Failure Loads ◽  
The Impact

scholarly journals In vitro investigation on the impact of airway mucus on drug dissolution and absorption at the air-epithelium interface in the lungs

2019 ◽  
Vol 141 ◽  
pp. 210-220 ◽  
Author(s):  
Emanuela Cingolani ◽  
Safar Alqahtani ◽  
Robyn C Sadler ◽  
David Prime ◽  
Snjezana Stolnik ◽  
...  
Keyword(s):  
Drug Dissolution ◽  
In Vitro Investigation ◽  
Airway Mucus ◽  
The Impact

In vitro investigation on the impact of the surface-active excipients Cremophor EL, Tween 80 and Solutol HS 15 on the metabolism of midazolam

2004 ◽  
Vol 25 (1) ◽  
pp. 37-49 ◽  
Author(s):  
Roberto C. Bravo González ◽  
Jörg Huwyler ◽  
Franziska Boess ◽  
Isabelle Walter ◽  
Beate Bittner
Keyword(s):  
Tween 80 ◽  
Cremophor El ◽  
In Vitro Investigation ◽  
Surface Active ◽  
Solutol Hs 15 ◽  
The Impact

scholarly journals In vitro investigation of the impact of pulsatile blood flow on the vascular architecture of decellularized porcine kidneys

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Peter R. Corridon
Keyword(s):  
Blood Flow ◽  
Blood Perfusion ◽  
Pulsatile Blood Flow ◽  
Venous Outflow ◽  
Venous Flow ◽  
Vascular Architecture ◽  
Arterial Perfusion ◽  
In Vitro Investigation ◽  
The Impact

AbstractA method was established using a scaffold-bioreactor system to examine the impact pulsatile blood flow has on the decellularized porcine kidney vascular architecture and functionality. These scaffolds were subjected to continuous arterial perfusion of whole blood at normal physiological (650 ml/min and 500 ml/min) and pathophysiological (200 ml/min) rates to examine dynamic changes in venous outflow and micro-/macrovascular structure and patency. Scaffolds subjected to normal arterial perfusion rates observed drops in venous outflow over 24 h. These reductions rose from roughly 40% after 12 h to 60% after 24 h. There were no apparent signs of clotting at the renal artery, renal vein, and ureter. In comparison, venous flow rates decreased by 80% to 100% across the 24 h in acellular scaffolds hypoperfused at a rate of 200 ml/min. These kidneys also appeared intact on the surface after perfusion. However, they presented several arterial, venous, and ureteral clots. Fluoroscopic angiography confirmed substantial alterations to normal arterial branching patterns and patency, as well as parenchymal damage. Scanning electron microscopy revealed that pulsatile blood perfusion significantly disrupted glomerular microarchitecture. This study provides new insight into circumstances that limit scaffold viability and a simplified model to analyze conditions needed to prepare more durable scaffolds for long-term transplantation.

scholarly journals Impact of Horse Hoof Wall with Different Solid Surfaces

2020 ◽  
Vol 10 (23) ◽  
pp. 8743
Author(s):  
Jing Zhao ◽  
Dan B. Marghitu ◽  
John Schumacher ◽  
Wenzhong Wang
Keyword(s):  
Contact Force ◽  
Coefficient Of Friction ◽  
Coefficient Of Restitution ◽  
Solid Surfaces ◽  
Effective Coefficient ◽  
In Vitro Investigation ◽  
Equine Hoof ◽  
Impact Angles ◽  
The Impact

This study aimed to investigate the impact of a horse hoof wall on three solid surfaces: steel, concrete and asphalt. Impact experiments were conducted for different impact angles and different initial impact velocities. The effect of impact surfaces, impact angles and initial impact velocities on the coefficient of restitution and the effective coefficient of friction were tested using one-way ANOVA. Analytical and numerical modeling of the impact were developed. The impact interval was divided into two phases: compression and restitution. For compression, a contact force with a damping term was used. The restitution was characterized by an elastic contact force. The stiffness and damping coefficients of the contact force were estimated from the normal impacts. The simulated velocities after the oblique impacts were compared to the velocities in the in vitro investigation. The coefficient of restitution varied significantly on different surfaces. The effective coefficient of friction was lower on steel compared to concrete and asphalt. The model presented in this study can be applied to refine the impact simulation of the equine hoof during locomotion.

scholarly journals In Vitro Investigation on Degradable Mg-Based Biomaterial under the Impact of the Serum Glycoprotein Fetuin

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5005
Author(s):  
Heike Helmholz ◽  
Blessing Adejube ◽  
Bérengère Luthringer-Feyerabend ◽  
Regine Willumeit-Römer
Keyword(s):  
Serum Proteins ◽  
Degradation Products ◽  
Culture Conditions ◽  
Material Surface ◽  
Degradation Behavior ◽  
Immersion Medium ◽  
In Vitro Investigation ◽  
The Impact

Biomedical applications of magnesium (Mg) and its alloys are generally dependent on their degradation behavior in vivo. Despite its attractive properties, which make Mg suitable for orthopedic applications, the in vivo material-tissue (bone, blood, and lymph tissues) interaction is not yet fully understood. To investigate the influence of major serum proteins on the degradation, this study focused on fetuin, which is one of the major non-collagenous plasma proteins and which is essential for biomineralization. This study used a physiological setup to investigate the influence of fetuin on the degradation behavior of pure Mg in the presence of calcium (Ca). Extruded pure Mg samples were immersed under cell culture conditions in Hank’s balanced salt solution (HBSS) under defined Ca regimes. The results showed a significant decrease in the degradation rate (DR) when both fetuin and Ca were present in an immersion medium as compared to media where they were not simultaneously present. A possible reason for this behavior was the forming of a dense, protein-degradation products protection barrier at the material surface. Furthermore, the limitation of freely available Ca might be a reason for a decreased degradation. The cultivation of primary osteoblasts (pOB) was possible at the fetuin-coated Mg-surface without additional serum supplementation.

In vitro investigation on the impact of Solutol HS 15 on the uptake of colchicine into rat hepatocytes

2004 ◽  
Vol 279 (1-2) ◽  
pp. 27-31 ◽  
Author(s):  
Roberto Carlos Bravo González ◽  
Franziska Boess ◽  
Evelyne Durr ◽  
Nathalie Schaub ◽  
Beate Bittner
Keyword(s):  
Rat Hepatocytes ◽  
In Vitro Investigation ◽  
Solutol Hs 15 ◽  
The Impact

scholarly journals An in vitro investigation to understand the synergistic role of MMPs-1 and 9 on articular cartilage biomechanical properties

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Allison Mixon ◽  
Andrew Savage ◽  
Ahmed Suparno Bahar-Moni ◽  
Malek Adouni ◽  
Tanvir Faisal
Keyword(s):  
Peak Load ◽  
Biomechanical Properties ◽  
Cartilage Degradation ◽  
Enzyme Concentration ◽  
Cartilage Explants ◽  
Healthy State ◽  
In Vitro Investigation ◽  
Degradative Enzymes ◽  
The Impact

AbstractMatrix metalloproteinases (MMPs) play a crucial role in enzymatically digesting cartilage extracellular matrix (ECM) components, resulting in degraded cartilage with altered mechanical loading capacity. Overexpression of MMPs is often caused by trauma, physiologic conditions and by disease. To understand the synergistic impact MMPs have on cartilage biomechanical properties, MMPs from two subfamilies: collagenase (MMP-1) and gelatinase (MMP-9) were investigated in this study. Three different ratios of MMP-1 (c) and MMP-9 (g), c1:g1, c3:g1 and c1:g3 were considered to develop a degradation model. Thirty samples, harvested from bovine femoral condyles, were treated in groups of 10 with one concentration of enzyme mixture. Each sample was tested in a healthy state prior to introducing degradative enzymes to establish a baseline. Samples were subjected to indentation loading up to 20% bulk strain. Both control and treated samples were mechanically and histologically assessed to determine the impact of degradation. Young’s modulus and peak load of the tissue under indentation were compared between the control and degraded cartilage explants. Cartilage degraded with the c3:g1 enzyme concentration resulted in maximum 33% reduction in stiffness and peak load compared to the other two concentrations. The abundance of collagenase is more responsible for cartilage degradation and reduced mechanical integrity.

scholarly journals An in vitro investigation of species-dependent intestinal transport of selenium and the impact of this process on selenium bioavailability

2012 ◽  
Vol 109 (12) ◽  
pp. 2126-2134 ◽  
Author(s):  
Celine Thiry ◽  
Ann Ruttens ◽  
Luc Pussemier ◽  
Yves-Jacques Schneider
Keyword(s):  
Human Subjects ◽  
Intestinal Transport ◽  
Inorganic Species ◽  
In Vitro Investigation ◽  
Selenium Bioavailability ◽  
Species Specific ◽  
The Impact ◽  
Paracellular Diffusion

A range of Se species has been shown to occur in a variety of different foodstuffs. Depending on its speciation, Se is more or less bioavailable to human subjects. In the present study, the role of speciation as a determinant of Se bioavailability was addressed with an investigation of species-specific mechanisms of transport at the intestinal level. The present work focused on four distinct Se compounds (selenate (Se(VI)), selenite (Se(IV)), selenomethionine (SeMet) and methylselenocysteine (MeSeCys)), whose intestinal transport was mimicked through an in vitro bicameral model of enterocyte-like differentiated Caco-2 cells. Efficiency of Se absorption was shown to be species dependent (SeMet>MeSeCys>Se(VI)>Se(IV)). In the case of SeMet, MeSeCys and Se(VI), the highly polarised passage from the apical to basolateral pole indicated that a substantial fraction of transport was transcellular, whilst results for Se(IV) indicated paracellular diffusion. Passage of the organic Se species (SeMet and MeSeCys) became saturated after 3 h, but no such effect was observed for the inorganic species. In addition, SeMet and MeSeCys transport was significantly inhibited by their respective S analogues methionine and methylcysteine, which suggests a common transport system for both kinds of compounds.

scholarly journals Impact of Aging on the Accuracy of 3D-Printed Dental Models: An In Vitro Investigation

2020 ◽  
Vol 9 (5) ◽  
pp. 1436 ◽  
Author(s):  
Tim Joda ◽  
Lea Matthisson ◽  
Nicola U. Zitzmann
Keyword(s):  
Reference Model ◽  
In Vitro Study ◽  
Deviation Analysis ◽  
Fixed Dental Prosthesis ◽  
In Vitro Investigation ◽  
Dental Models ◽  
3D Printed ◽  
Level Of Significance ◽  
The Impact

The aim of this in vitro study was to analyze the impact of model aging on the accuracy of 3D-printed dental models. A maxillary full-arch reference model with prepared teeth for a three-unit fixed dental prosthesis was scanned ten times with an intraoral scanner (3Shape TRIOS Pod) and ten models were 3D printed (Straumann P-Series). All models were stored under constant conditions and digitized with a desktop scanner after 1 day; 1 week; and 2, 3, and 4 weeks. For accuracy, a best-fit algorithm was used to analyze the deviations of the abutment teeth (GFaI e.V Final Surface®). Wilcoxon Rank Sum Tests were used for comparisons with the level of significance set at α = 0.05. Deviation analysis of the tested models showed homogenous intragroup distance calculations at each timepoint. The most accurate result was for 1 day of aging (3.3 ± 1.3 µm). A continuous decrease in accuracy was observed with each aging stage from day 1 to week 4. A time-dependent difference was statistically significant after 3 weeks (p = 0.0008) and 4 weeks (p < 0.0001). Based on these findings, dental models should not be used longer than 3 to 4 weeks after 3D printing for the fabrication of definitive prosthetic reconstructions.

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