scholarly journals Design and Synthesis of 99mTcN-Labeled Dextran-Mannose Derivatives for Sentinel Lymph Node Detection

2018 ◽  
Vol 11 (3) ◽  
pp. 70 ◽  
Author(s):  
Alessandra Boschi ◽  
Micòl Pasquali ◽  
Claudio Trapella ◽  
Alessandro Massi ◽  
Petra Martini ◽  
...  

Background: New approaches based on the receptor-targeted molecular interaction have been recently developed with the aim to investigate specific probes for sentinel lymph nodes. In particular, the mannose receptors expressed by lymph node macrophages became an attractive target and different multifunctional mannose derivate ligands for the labeling with 99mTc have been developed. In this study, we report the synthesis of a specific class of dextran-based, macromolecular, multifunctional ligands specially designed for labeling with the highly stable [99mTc≡N]2+ core. Methods: The ligands have been obtained by appending to a macromolecular dextran scaffold pendant arms bearing a chelating moiety for the metallic group and a mannosyl residue for allowing the interaction of the resulting macromolecular 99mTc conjugate with specific receptors on the external membrane of macrophages. Two different chelating systems have been selected, S-methyl dithiocarbazate [H2N‒NH‒C(=S)SCH3=HDTCZ] and a sequence of two cysteine residues, that in combination with a monophosphine coligand, are able to bind the [99mTc≡N]2+ core. Conclusions: High-specific-activity labeling has been obtained by simple mixing and heating of the [99mTc≡N]2+ group with the new mannose-dextran derivatives.

1970 ◽  
Vol 46 (2) ◽  
pp. 269-278 ◽  
Author(s):  
T. CHARD ◽  
M. J. KITAU ◽  
J. LANDON

SUMMARY A simple and rapid method is described for labelling oxytocin with 131I at a high specific activity. This method is compared with those of previous workers. A satisfactory antiserum has been raised by direct intra-lymph node injection of oxytocin adsorbed to carbon microparticles. A number of methods for separating antibody-bound from free oxytocin are described, and reasons given for preferring a procedure using ammonium sulphate precipitation. These data form the basis for developing a radioimmunoassay intended for the determination of oxytocin in human plasma.


1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl

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.


1962 ◽  
Vol 08 (03) ◽  
pp. 425-433 ◽  
Author(s):  
Ewa Marciniak ◽  
Edmond R Cole ◽  
Walter H Seegers

SummarySuitable conditions were found for the generation of autoprothrombin C from purified prothrombin with the use of Russell’s viper venom or trypsin. DEAE chromatographed prothrombin is structurally altered and has never been found to yield autoprothrombin C and also did not yield it when Russell’s viper venom or trypsin were used. Autoprothrombin C is derived from prothrombin with tissue extract thromboplastin, but not in large amounts with the intrinsic clotting factors. With the latter thrombin and autoprothrombin III are the chief activation products. Autoprothrombin III concentrates were prepared from serum and upon activation with 25% sodium citrate solution or with Russell’s viper venom large amounts of autoprothrombin C were obtained, and this was of high specific activity. Theoretically trypsin is not a thrombolytic agent, but on the contrary should lead to intravascular clotting.


2021 ◽  
pp. 1-7
Author(s):  
Michael A. Reichenberger ◽  
Jagoda M. Urban-Klaehn ◽  
Jason V. Brookman ◽  
Joshua L. Peterson-Droogh ◽  
Jorge Navarro ◽  
...  

1964 ◽  
Vol 239 (11) ◽  
pp. 3743-3748 ◽  
Author(s):  
Joseph L. Izzo ◽  
William F. Bale ◽  
Mary Jane Izzo ◽  
Angela Roncone

Biochemistry ◽  
1997 ◽  
Vol 36 (7) ◽  
pp. 1943-1952 ◽  
Author(s):  
Alexandra Koschak ◽  
Robert O. Koch ◽  
Jessica Liu ◽  
Gregory J. Kaczorowski ◽  
Peter H. Reinhart ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document