Circulating Activities During Constant Infusion of Heparin or a Low Molecular Weight Derivative (Enoxaparine): Failure to Demonstrate any Circadian Variations

1987 ◽  
Vol 58 (04) ◽  
pp. 1068-1072 ◽  
Author(s):  
P Toulon ◽  
J F Vitoux ◽  
C Leroy ◽  
T Lecomte ◽  
M Roncato ◽  
...  

SummaryWe compared in six patients successively treated with an unfractionated heparin (UFH) and a low molecular weight heparin (LMWH) the variations in plasma anti-Xa activity, measured in a chromogenic assay, during a 36 h constant infusion. The values varied in a wider range during UHF infusion, but remained in the therapeutic range except once in one patient. No circadian rhythm could be demonstrated in our six patients. LMWH infusion yielded very constant anti-Xa circulating activities. In both cases, there were no significant modifications of three proteins with high heparin affinity (antithrombin III, heparin cofactor II, histidine-rich glycoprotein).Our results suggest that the circadian rhythm of the biological activities previously observed in patients treated with constant heparin infusion using clotting method is due to other factors than heparin itself.

Author(s):  
Makoto Ogata

Abstract Carbohydrates play important and diverse roles in the fundamental processes of life. We have established a method for accurately and a large scale synthesis of functional carbohydrates with diverse properties using a unique enzymatic method. Furthermore, various artificial glycan-conjugated molecules have been developed by adding these synthetic carbohydrates to macromolecules and to middle and low molecular weight molecules with different properties. These glycan-conjugated molecules have biological activities comparable to or higher than those of natural compounds, and present unique functions. In this review, several synthetic glycan-conjugated molecules are taken as examples to show design, synthesis and function.


Nephrology ◽  
2018 ◽  
Vol 23 (4) ◽  
pp. 317-322 ◽  
Author(s):  
Steve Siu-Man Wong ◽  
Wai-Yan Lau ◽  
Man-Luen Ng ◽  
Shuk-Yin Chan ◽  
So-Fan Chan ◽  
...  

1993 ◽  
Vol 128 (1) ◽  
pp. 88-94 ◽  
Author(s):  
Nobuyoshi Kokawa ◽  
Mareo Yamoto ◽  
Kenichi Furukawa ◽  
Ryosuke Nakano

We performed partial purification of low molecular weight luteinizing hormone binding inhibitor from porcine follicular fluids and examined its biological activities. Following ultrafiltration, gel filtration and anion exchange of the pooled porcine follicular fluids, low molecular weight fractions (500–10,000 MW) inhibited [125I]hLH binding to porcine granulosa cells in a dose-dependent manner. The binding inhibition kinetics study revealed that the luteinizing hormone binding inhibitor may indicate a non-competitive inhibition with [125I]hLH binding. In vitro bioassay using adult mouse testicular interstitial cells revealed that the partially purified luteinizing hormone binding inhibitor reduced ovine LH-stimulated testosterone and cAMP production in a dose-dependent manner, whereas the luteinizing hormone binding inhibitor did not affect basal production of testosterone and cAMP. The inhibitory activity was heat stable and did not disappear with activated charcoal adsorption. The results of the present study suggest that the luteinizing hormone binding inhibitor may play an important role as an ovarian non-steroidal regulator modulating the receptor binding of LH and LH-mediated steroidogenesis.


Marine Drugs ◽  
2019 ◽  
Vol 17 (7) ◽  
pp. 421 ◽  
Author(s):  
Kiichiro Teruya ◽  
Yoshihiro Kusumoto ◽  
Hiroshi Eto ◽  
Noboru Nakamichi ◽  
Sanetaka Shirahata

Low molecular weight fucoidan extract (LMF), prepared by an abalone glycosidase digestion of a crude fucoidan extracted from Cladosiphon novae-caledoniae Kylin, exhibits various biological activities, including anticancer effect. Various cancers express programmed cell death-ligand 1 (PD-L1), which is known to play a significant role in evasion of the host immune surveillance system. PD-L1 is also expressed in many types of normal cells for self-protection. Previous research has revealed that selective inhibition of PD-L1 expressed in cancer cells is critical for successful cancer eradication. In the present study, we analyzed whether LMF could regulate PD-L1 expression in HT1080 fibrosarcoma cells. Our results demonstrated that LMF suppressed PD-L1/PD-L2 expression and the growth of HT1080 cancer cells and had no effect on the growth of normal TIG-1 cells. Thus, LMF differentially regulates PD-L1 expression in normal and cancer cells and could serve as an alternative complementary agent for treatment of cancers with high PD-L1 expression.


1987 ◽  
Author(s):  
T G van Dinther ◽  
F Hol ◽  
D G Meuleman

The effects of various heparin(oid)s, standard heparin VII (SH), dermatan sulphate (DS), a low molecular weight fraction of heparin (UMW-H), FragminR (FRA), Org 10172 = low molecular weight heparinoid, the fraction of Org 10172 with high affinity for AT-III (HA-10172) and the low affinity fraction (LA-10172) respectively were examined on in vitro thrombin generation and inactivation.Thrombin inactivation in the presence of either heparin cofactor II (HC-II) or anti-thrombin III (AT-III) was assessed with two newly developed assays using the purified cofactors, thrombin and chromogenic substrate S2238 on microtiterplates. Thrombin generation in the presence of HC-II and AT-III was studied using purified factor Xa, prothrombin and blood platelet lysate and the residual thrombin activity was assessed amidolytically.The inhibition of the compounds on thrombin activity are summarized in the tableThe following conclusions can be drawn:- SH, LMW-H, HA-10172 and FRA potentiate the AT-III mediated inactivation of Ha more strongly than the HC-II mediated inactivation.- DS and LA-10172 show the reverse pattern of inactivation, while Org 10172 potentiates both inactivaton pathways to a similar extent.Thrombin generation in the presence of HC-II is inhibited by mw-heparin(oid)s at approx. 2-5 times lower concentrations than the HC-II mediated thrombin inactivation, while the inhibiting effect of SH in both assays is comparable.AT-III mediated thrombin generation inhibition and AT-III mediated thrombin inactivation is comparable as well for SH, LMW-H and FRA. In contrast, Org 10172 and its subfractions are approx. 10 times more potent on AT-III mediated thrombin generation inhibition than on AT-III mediated thrombin inactivation.Org 10172 shows low anti-thrombin activity and this activity is mainly mediated via FC-II.


2016 ◽  
Vol 9 (4) ◽  
pp. 630-635 ◽  
Author(s):  
Steve Siu-Man Wong ◽  
Wai-Yan Lau ◽  
Ping-Kwan Chan ◽  
Ching-Kit Wan ◽  
Yuk-Lun Cheng

2009 ◽  
Vol 102 (11) ◽  
pp. 865-873 ◽  
Author(s):  
Antonella Bisio ◽  
Davide Vecchietti ◽  
Laura Citterio ◽  
Marco Guerrini ◽  
Rahul Raman ◽  
...  

SummaryAs part of a more extensive investigation on structural features of different low-molecular-weight heparins (LMWHs) that can affect their biological activities, Enoxaparin,Tinzaparin and Dalteparin were characterised with regards to the distribution of different chain length oligosaccharides as determined by size-exclusion (SE) chromatography, as well as their structure as defined by 2D-NMR spectra (HSQC). The three LMWHs were also fractionated into high affinity (HA) and no affinity (NA) pools with regards to their ability to bind antithrombin (AT).The HA fractions were further subfractionated and characterised. For the parent LMWHs and selected fractions,molecular weight parameters were measured using a SE chromatographic system with a triple detector (TDA) to obtain absolute molecular weights. The SE chromatograms clearly indicate that Enoxaparin is consistently richer in shorter oligosaccharides than Tinzaparin and Dalteparin. Besides providing the content of terminal groups and individual glucosamine and uronic acid residues with different sulfate substituents, the HSQC-NMR spectra permitted us to evaluate and correlate the content of the pentasaccharide, AT-binding sequence A-G-A*-I-A (AT-bs) through quantification of signals of the disaccharide sequence G-A*.Whereas the percent content of HA species is approximately the same for the three LMWHs, substantial differences were observed for the chain distribution of AT-bs as a function of length, with the AT-bs being preferentially contained in the longest chains of each LMWH. The above information will be useful in establishing structure-activity relationships currently under way. This study is therefore critical for establishing correlations between structural features of LMWHs and their AT-mediated anticoagulant activity.


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