Radiosynthesis of high affinity fluorine-18 labeled GnRH peptide analogues: in vitro studies and in vivo assessment of brain uptake in rats

MedChemComm ◽  
2015 ◽  
Vol 6 (4) ◽  
pp. 708-714 ◽  
Author(s):  
Dag Erlend Olberg ◽  
Sven H. Hausner ◽  
Nadine Bauer ◽  
Jo Klaveness ◽  
Bård Indrevoll ◽  
...  
Keyword(s):  
Gnrh Receptor ◽  
Receptor Expression ◽  
In Vitro Studies ◽  
Imaging Agents ◽  
Brain Uptake ◽  
High Affinity ◽  
Peptide Analogues ◽  
In Vivo Assessment

A series of high affinity 18F-GnRH peptides have been synthesized and show utility as imaging agents for GnRH receptor expression in vivo.

scholarly journals in vivo and in vitro studies on a new type of plasminogen activator with fibrin high-affinity from human urine.

1993 ◽  
Vol 61 ◽  
pp. 78
Author(s):  
Shigeru Taguchi ◽  
Kimihiro Ogino ◽  
Chiaki Shirato ◽  
Isao Aoju ◽  
Kyozo Ishikawa ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Human Urine ◽  
In Vitro Studies ◽  
High Affinity ◽  
New Type

scholarly journals Increased brain uptake of targeted nanoparticles by adding an acid-cleavable linkage between transferrin and the nanoparticle core

2015 ◽  
Vol 112 (40) ◽  
pp. 12486-12491 ◽  
Author(s):  
Andrew J. Clark ◽  
Mark E. Davis
Keyword(s):  
Brain Parenchyma ◽  
Common Mechanism ◽  
High Avidity ◽  
Brain Uptake ◽  
Targeted Nanoparticles ◽  
High Affinity ◽  
The Brain ◽  
Nanoparticle Core

Most therapeutic agents are excluded from entering the central nervous system by the blood–brain barrier (BBB). Receptor mediated transcytosis (RMT) is a common mechanism used by proteins, including transferrin (Tf), to traverse the BBB. Here, we prepared Tf-containing, 80-nm gold nanoparticles with an acid-cleavable linkage between the Tf and the nanoparticle core to facilitate nanoparticle RMT across the BBB. These nanoparticles are designed to bind to Tf receptors (TfRs) with high avidity on the blood side of the BBB, but separate from their multidentate Tf–TfR interactions upon acidification during the transcytosis process to allow release of the nanoparticle into the brain. These targeted nanoparticles show increased ability to cross an in vitro model of the BBB and, most important, enter the brain parenchyma of mice in greater amounts in vivo after systemic administration compared with similar high-avidity nanoparticles containing noncleavable Tf. In addition, we investigated this design with nanoparticles containing high-affinity antibodies (Abs) to TfR. With the Abs, the addition of the acid-cleavable linkage provided no improvement to in vivo brain uptake for Ab-containing nanoparticles, and overall brain uptake was decreased for all Ab-containing nanoparticles compared with Tf-containing ones. These results are consistent with recent reports of high-affinity anti-TfR Abs trafficking to the lysosome within BBB endothelium. In contrast, high-avidity, Tf-containing nanoparticles with the acid-cleavable linkage avoid major endothelium retention by shedding surface Tf during their transcytosis.

The Venom of the Boomslang (Dispholidus Typus): In Vivo and in Vitro Studies

1969 ◽  
Vol 21 (02) ◽  
pp. 234-244 ◽  
Author(s):  
N Mackay ◽  
J.C Ferguson ◽  
Antonia Bagshawe ◽  
A.T.T Forrester ◽  
G.P Mcnicol
Keyword(s):  
In Vitro Studies

SummaryAn account is given of the effects of boomslang venom in man. Evidence was found of a fibrinolytic state apparently secondary to the coagulant action of the venom. These features rapidly responded to the administration of specific antivenom. In vitro studies, using a homogenate of boomslang parotids, confirmed the coagulant properties of the venom and showed them to be of much greater potency than the proteolytic actions.

Effects of Heparin Oligosaccharides with High Affinity for Antithrombin III in Experimental Venous Thrombosis

1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl
Keyword(s):  
Antithrombin Iii ◽  
Specific Activity ◽  
High Specific Activity ◽  
Factor Xa ◽  
Blood Levels ◽  
Thrombin Time ◽  
High Affinity ◽  
Very High

SummaryThe in vitro and in vivo characteristics of two oligosaccharide heparin fragments have been compared to those of unfractionated mucosal heparin. A decasaccharide fragment had essentially no activity by APTT or calcium thrombin time assays in vitro, but possessed very high specific activity by anti-Factor Xa assays. When injected into rabbits at doses of up to 80 ¼g/kg, this fragment was relatively ineffective in impairing stasis thrombosis despite producing high blood levels by anti-Xa assays. A 16-18 monosaccharide fragment had even higher specific activity (almost 2000 iu/mg) by chromogenic substrate anti-Xa assay, with minimal activity by APTT. When injected in vivo, this fragment gave low blood levels by APTT, very high anti-Xa levels, and was more effective in preventing thrombosis than the decasaccharide fragment. However, in comparison with unfractionated heparin, the 16-18 monosaccharide fragment was only partially effective in preventing thrombosis, despite producing much higher blood levels by anti-Xa assays.It is concluded that the high-affinity binding of a heparin fragment to antithrombin III does not by itself impair venous thrombogenesis, and that the anti-Factor Xa activity of heparin is only a partial expression of its therapeutic potential.

Effect of X-irradiation on gene expression of rat liver chemokines: in vivo and in vitro studies

2008 ◽  
Vol 46 (01) ◽  
Author(s):  
F Moriconi ◽  
H Christiansen ◽  
H Christiansen ◽  
N Sheikh ◽  
J Dudas ◽  
...  
Keyword(s):  
Gene Expression ◽  
Rat Liver ◽  
In Vitro Studies ◽  
X Irradiation
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