A biokinetic model for nickel released from cardiovascular devices

2016 ◽  
Vol 80 ◽  
pp. 1-8 ◽  
Author(s):  
David M. Saylor ◽  
Lingga Adidharma ◽  
Jeffrey W. Fisher ◽  
Ronald P. Brown
Friction ◽  
2021 ◽  
Author(s):  
Xiaogang Zhang ◽  
Yali Zhang ◽  
Zhongmin Jin

AbstractNumerous medical devices have been applied for the treatment or alleviation of various diseases. Tribological issues widely exist in those medical devices and play vital roles in determining their performance and service life. In this review, the bio-tribological issues involved in commonly used medical devices are identified, including artificial joints, fracture fixation devices, skin-related devices, dental restoration devices, cardiovascular devices, and surgical instruments. The current understanding of the bio-tribological behavior and mechanism involved in those devices is summarized. Recent advances in the improvement of tribological properties are examined. Challenges and future developments for the prospective of bio-tribological performance are highlighted.


2021 ◽  
Vol 22 (2) ◽  
pp. 978
Author(s):  
Skadi Lau ◽  
Manfred Gossen ◽  
Andreas Lendlein ◽  
Friedrich Jung

Although cardiovascular devices are mostly implanted in arteries or to replace arteries, in vitro studies on implant endothelialization are commonly performed with human umbilical cord-derived venous endothelial cells (HUVEC). In light of considerable differences, both morphologically and functionally, between arterial and venous endothelial cells, we here compare HUVEC and human umbilical cord-derived arterial endothelial cells (HUAEC) regarding their equivalence as an endothelial cell in vitro model for cardiovascular research. No differences were found in either for the tested parameters. The metabolic activity and lactate dehydrogenase, an indicator for the membrane integrity, slightly decreased over seven days of cultivation upon normalization to the cell number. The amount of secreted nitrite and nitrate, as well as prostacyclin per cell, also decreased slightly over time. Thromboxane B2 was secreted in constant amounts per cell at all time points. The Von Willebrand factor remained mainly intracellularly up to seven days of cultivation. In contrast, collagen and laminin were secreted into the extracellular space with increasing cell density. Based on these results one might argue that both cell types are equally suited for cardiovascular research. However, future studies should investigate further cell functionalities, and whether arterial endothelial cells from implantation-relevant areas, such as coronary arteries in the heart, are superior to umbilical cord-derived endothelial cells.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Vera Höllriegl ◽  
Nina Petoussi-Henss ◽  
Kerstin Hürkamp ◽  
Juan Camilo Ocampo Ramos ◽  
Wei Bo Li

Abstract Purpose Ra-223 dichloride (223Ra, Xofigo®) is used for treatment of patients suffering from castration-resistant metastatic prostate cancer. The objective of this work was to apply the most recent biokinetic model for radium and its progeny to show their radiopharmacokinetic behaviour. Organ absorbed doses after intravenous injection of 223Ra were estimated and compared to clinical data and data of an earlier modelling study. Methods The most recent systemic biokinetic model of 223Ra and its progeny, developed by the International Commission on Radiological Protection (ICRP), as well as the ICRP human alimentary tract model were applied for the radiopharmacokinetic modelling of Xofigo® biodistribution in patients after bolus administration. Independent kinetics were assumed for the progeny of 223Ra. The time activity curves for 223Ra were modelled and the time integrated activity coefficients, $$ \overset{\sim }{a}\left({r}_S,{T}_D\right), $$ a ~ r S T D , in the source regions for each progeny were determined. For estimating the organ absorbed doses, the Specific Absorbed Fractions (SAF) and dosimetric framework of ICRP were used together with the aforementioned $$ \overset{\sim }{a}\left({r}_S,{T}_D\right) $$ a ~ r S T D values. Results The distribution of 223Ra after injection showed a rapid plasma clearance and a low urinary excretion. Main elimination was via faeces. Bone retention was found to be about 30% at 4 h post-injection. Similar tendencies were observed in clinical trials of other authors. The highest absorbed dose coefficients were found for bone endosteum, liver and red marrow, followed by kidneys and colon. Conclusion The biokinetic modelling of 223Ra and its progeny may help to predict their distributions in patients after administration of Xofigo®. The organ dose coefficients of this work showed some variation to the values reported from clinical studies and an earlier compartmental modelling study. The dose to the bone endosteum was found to be lower by a factor of ca. 3 than previously estimated.


2016 ◽  
Vol 92 ◽  
pp. 216-229 ◽  
Author(s):  
Raimund Bürger ◽  
Julio Careaga ◽  
Stefan Diehl ◽  
Camilo Mejías ◽  
Ingmar Nopens ◽  
...  

2017 ◽  
Vol 21 (2) ◽  
pp. 138-141 ◽  
Author(s):  
Toshihide Mizuno ◽  
Tomonori Tsukiya ◽  
Yoshiaki Takewa ◽  
Eisuke Tatsumi

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