Search results for "Heparin"
showing 10 items of 191 documents
Timing of Heparin Addition to the Biomolecular Corona Influences the Cellular Uptake of Nanocarriers.
2019
Few studies have considered the interaction of nanocarriers with drugs and the implications for their individual efficiency. Here, we demonstrate that heparin, a common anticoagulant, interacts with nanocarriers. Hence, nanocarriers, precoated with heparin and plasma in different conditions, were incubated with cancer cells, as well as primary cells from human blood. The relation between the timing of the heparin's addition to the nanocarrier and the cellular uptake extent was assessed by flow cytometry. Through proteomics the effect of heparin on the biomolecular corona composition was determined. We found that HeLa cells, monocytes and macrophages reacted differently to the presence of he…
Einsatz von niedermolekularem Heparin zur Antikoagulation in der Schwangerschaft
2008
A 26-year-old woman, on bedrest since the 6th week of pregnancy because of threatened abortion, developed thrombosis in the left iliac, superficial femoral and common femoral veins with small pulmonary emboli in the 11th week. Inhibitor deficiency was excluded. The thrombosis was only partially recanalized by unfractionated heparin at therapeutic dosage (38,400 IU per 24 h). As thrombolysis treatment and oral anticoagulation were contraindicated because of the threatened abortion, coagulation with low molecular weight heparin (LMWH) was started in the 18th week (5000 anti-Xa units daily subcutaneously). Maximal anti-Xa activity in plasma never exceeded 0.3 U/ml and there were no complicatio…
Kinetic analysis and molecular modeling of the inhibition mechanism of roneparstat (SST0001) on human heparanase
2016
Heparanase is a β-d-glucuronidase which cleaves heparan sulfate chains in the extracellular matrix and on cellular membranes. A dysregulated heparanase activity is intimately associated with cell invasion, tumor metastasis and angiogenesis, making heparanase an attractive target for the development of anticancer therapies. SST0001 (roneparstat; Sigma-Tau Research Switzerland S.A.) is a non-anticoagulant 100% N-acetylated and glycol-split heparin acting as a potent heparanase inhibitor, currently in phase I in advanced multiple myeloma. Herein, the kinetics of heparanase inhibition by roneparstat is reported. The analysis of dose-inhibition curves confirmed the high potency of roneparstat (I…
Heparan sulfate proteoglycans interact exclusively with conformationally intact HPV L1 assemblies: basis for a virus-like particle ELISA.
2004
In this article, we demonstrate that interaction of human papillomavirus-like particles (HPV-VLPs) with the putative glucosaminoglycan binding receptor is strictly dependent on conformational integrity. Such conformations are present on VLPs and capsomeres but not on monomers of the major capsid protein, L1, confirming reports that capsomeres can induce virus-neutralizing antibodies. Furthermore, we show the suitability of this specific interaction for development of VLP-based enzyme-linked immunosorbent assays (ELISAs), using heparin for indirect coupling of VLPs to microtiter plates, which may add an intrinsic quality control. This avoids presentation of linear, often highly cross-reactiv…
Expression and glycosylation studies of human FGF receptor 4
2001
Fibroblast growth factor receptor subtype 4 (FGFR4) has been shown to have special activation properties and just one splicing form, unlike the other FGFRs. FGFR4 overexpression is correlated with breast cancer and therefore FGFR4 is a target for drug design. Our aim is to overexpress high amounts of homogeneous FGFR4 extracellular domain (FGFR4ed) for structural studies. We show that baculovirus-insect cell-expressed FGFR4ed is glycosylated on three (N88, N234, and N266) of the six possible N-glycosylation sites but is not O-glycosylated. The deglycosylated triple mutant was expressed and had binding properties similar to those of glycosylated FGFR4ed, but was still heterogeneous. Large am…
D-Dimer, Thrombin-Antithrombin III-Komplex (TAT) und Prothrombinfragment 1+2 (PTF)
1997
Two groups of 15 patients each with disseminated intravascular coagulation in association with septic disease were treated with low-molecular-weight heparin (lmw-heparin) in different dosages (group I: 1.5-5 IE/kg body weight (BW) per hour; group II: 8-15 IE/kg BW). We studied the levels of D-dimer, thrombin-antithrombin III complex (TAT), prothrombin fragments 1 and 2 (PTF), and global tests of coagulation like prothrombin time (PT), activated partial thromboplastin time (PTT), thrombin time (TT) and platelet count, plasminogen activation (PA) and fibrinogen concentration to estimate the success of heparin therapy in the two groups. TT and fibrinogen concentration were not suitable to foll…
Second-generation Langerhans cells originating from epidermal precursors are essential for CD8+ T cell priming.
2014
Abstract In vivo studies questioned the ability of Langerhans cells (LCs) to mediate CD8+ T cell priming. To address this issue, we used intradermal immunization with plasmid DNA, a system in which activation of CD8+ T cells depends on delayed kinetics of Ag presentation. We found that dendritic cells (DCs) located in the skin at the time of immunization have limited ability to activate CD8+ T cells. This activity was mediated by a second generation of DCs that differentiated in the skin several days after immunization, as well as by lymph node–resident DCs. Intriguingly, CD8+ T cell responses were not affected following treatment with clodronate liposomes, immunization of CCR2−/− mice, or …
Manejo de los anticoagulantes orales de acción directa en el período perioperatorio y técnicas invasivas
2012
The new direct-acting oral anticoagulants (ACOD) in patients on prolonged treatment require the need to balance the risk of haemorrhage by administering them against the risk of thrombosis on withdrawing them. Recommendations for their management are proposed in the present article: A) Thromboprophylaxis and general anaesthesia: the performing of regional anaesthesia if administered with an ACOD as thromboprophylaxis requires some safety intervals based on their pharmacokinetic parameters; B) Management of ACOD in elective surgery: in patients with normal renal function and a low haemorrhage/thrombosis risk, stop the ACOD two days before the surgery; it the haemorrhage/thrombosis risk is hi…
Heparin functionalized polyaspartamide/polyester scaffold for potential blood vessel regeneration
2013
An interesting issue in tissue engineering is the development of a biodegradable vascular graft able to substitute a blood vessel and to allow its complete regeneration. Here, we report a new scaffold potentially useful as a synthetic vascular graft, produced through the electrospinning of α,β-poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-D,L-aspartamide-graft-polylactic acid (PHEA-EDA-g-PLA) in the presence of polycaprolactone (PCL). The scaffold degradation profile has been evaluated as well as the possibility to bind heparin to electrospun fibers, being it a known anticoagulant molecule able to bind growth factors. In vitro cell compatibility has been investigated using human vascular e…