OBJECTIVETo evaluate the anticoagulant and antineoplastic activities of chemically modified low-molecular-weight heparin (LMWH).

METHODSLMWH obtained by splitting unfractionated heparin (UFH) with sodium periodate oxidation and sodium borohydride reduction was subjected to acetylation catalyzed by DCC and DMAP to produce acetylated LMWH (ALMWH). The anticoagulant activity of ALMWH was determined in mice, and its antiproliferative and anti-invasion activities was assessed in human breast cancer cells MDA-MB-231 and MFC-7.

RESULTSThe anticoagulant activity of LMWH was decreased significantly after acetylation. The concentrations of commercial LMWH* and ALMWH for doubling the coagulation time (CT) were 33.04 µmol/L and 223.56 µmol/L, respectively, and the IC(50) of ALMWH for doubling CT was 6 times of that of LMWH*. ALMWH and LMWH at 0.1, 0.3, 0.9, 2.7 and 8.1 mmol/L both significantly inhibited the proliferation of MDA-MB-231 and MCF-7 cells in a concentration-dependent manner, but ALMWH produced stronger inhibitory effects. The IC(50) of LMWH and ALMWH for inhibiting cell proliferation was 3168.4 µmol/L and 152.6 µmol/L in MCF-7 cells, and 12299.6 µmol/L and 22.2 µmol/L in MDA-MB-231 cells, respectively. ALMWH and LMWH all markedly suppressed the invasion of MDA-MB-231 cells with comparable effects.

CONCLUSIONChemical modification of structure can endow LMWH with a low anticoagulant and high antiproliferative activities.

Animals ; Anticoagulants ; chemistry ; pharmacology ; Antineoplastic Agents ; chemistry ; pharmacology ; Blood Coagulation ; Blood Coagulation Tests ; Cell Line, Tumor ; Heparin ; chemistry ; Heparin, Low-Molecular-Weight ; chemistry ; pharmacology ; Humans ; Mice

Animals ; Heparin ; pharmacology ; Hepatocytes ; cytology ; metabolism ; Mice ; Promoter Regions, Genetic ; genetics ; Transforming Growth Factor beta ; genetics

The study was purposed to explore the suitable platelet activators to be used in slide platelet aggregation test. Experiments were as follows: (1) to detect the intensity and time in 15 healthy donors' platelet aggregation tests induced by cationic propyl gallate (c-PG) and the usual platelet activators: ADP, collagen, epinephrine, arachidonic acid and ristocentin, respectively; (2) to detect the time in platelet aggregation tests of 15 healthy donors induced by c-PG and the above usual platelet activators respectively after addition of PGI2, cAMP or EDTA; (3) to detect the time in 15 healthy donors' platelet aggregation tests induced by c-PG after addition of heparin; (4) to detect the intensity and time of platelet aggregation induced by c-PG at the platelet count of (240-15) x 10(9)/L, (5) to detect the time of platelet aggregation induced by c-PG in eight patients each of whom had taken 100 mg aspirin per day for five days. The results showed that (1) c-PG reduced the strongest intensity of platelet aggregation and the time taken was appropriate, (2) c-PG was the most effective activator to reveal the inhibitive effect on platelet by PGI2, cAMP or EDTA, (3) 0.5 - 3 U/ml heparin did not significantly change the platelet aggregation induced by c-PG, (4) 15 healthy donors' platelet aggregation induced by c-PG displayed clearly on the slide until the platelet count below 30 x 10(9)/L, (5) The platelet aggregation time induced by c-PG was significantly prolonged in eight patients who had taken aspirin. In conclusion, compared to the usual platelet activators, c-PG has remarkable potential advantages when used in slide platelet aggregation test.
Cyclic AMP ; pharmacology ; Edetic Acid ; pharmacology ; Epoprostenol ; pharmacology ; Heparin ; pharmacology ; Humans ; Male ; Platelet Activation ; drug effects ; Platelet Aggregation ; drug effects ; Propyl Gallate ; pharmacology

BACKGROUNDAlthough low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxaparin, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time.

METHODSA total of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied.

RESULTSThe activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r = 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU, diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant.

CONCLUSIONSThe glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin. The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-IIa activities.

Adult ; Anticoagulants ; pharmacology ; Blood Coagulation ; drug effects ; Blood Coagulation Tests ; Coagulants ; pharmacology ; Female ; Glass ; Heparin, Low-Molecular-Weight ; pharmacology ; Humans ; Kaolin ; pharmacology ; Male ; Middle Aged ; Nadroparin ; pharmacology

Lipoprotein lipase (LPL) is known to be attached to the luminal surface of vascular endothelial cells in a complex with membrane-bound heparan sulfate, and released into blood stream by heparin. LPL that catalyzes hydrolysis of triglyceride (TGL) on chylomicron and VLDL into two fatty acids and monoacylglycerol, is also implicated to participate in an enhancement of cholesterol uptake by arterial endothelial cells in vitro. But little is known about the LPL-mediated cholesterol uptake in physiological state. In this study, changes in blood lipid composition and levels of lipoproteins were determined after the injection of heparin in human. The level of LPL in plasma was increased from 0 to 11 mU/ml within 30-40 min post-heparin administration and decreased to the basal level within 2 h. The level of TGL in plasma decreased from 70 mg/dl to 20 mg/dl within 1 h and gradually increased to 80 mg/dl within 4 h. However the level of total cholesterol in plasma remained at 140 mg/dl during an experimental period of 4 h. Analysis of Lipoproteins in plasma by NaBr density gradient ultracentrifugation showed that the level of VLDL decreased from 50 mg/dl to 10 mg/dl within 1-2 h and returned to normal plasm level at 4 h. However there were no significant changes in the level of LDL and HDL. These results suggest that, at least, in normo-lipidemic subjects, increased free plasm LPL acts primarily on VLDL and failed to show any significant uptake of cholesterol-rich lipoproteins in human.
Adult ; Cholesterol/blood ; Heparin/pharmacology* ; Heparin/administration & dosage ; Human ; Immunoblotting ; Lipoprotein Lipase/blood* ; Lipoproteins/blood* ; Lipoproteins, HDL/blood ; Lipoproteins, LDL/blood ; Lipoproteins, VLDL/blood ; Triglycerides/blood

BACKGROUNDDue to lack of point-of-care testing, the use of low-molecular-weight heparin (LMWH) therapy in some special patients is restricted. This study was designed to explore the effects of LMWH on clot rate (CR) and activated clotting time (ACT), and to search for an appropriate method for bedside monitoring of anticoagulant activity of LMWH.

METHODSThirty-two healthy volunteers were selected from the staff of Beijing Tongren Hospital. CR and ACT were measured with different reagents (glass beads, diatomite, kaolin and magnetic bar) on blood samples spiked with increasing concentrations of LMWH (dalteparin, 0.2-1.8 IU/ml). Correlations between concentrations of LMWH and values of CR and ACT were analysed based on the data obtained and regression analysis was performed to establish a regression equation.

RESULTSWith the increase in doses of dalteparin, CR values reduced gradually. The values of CR of four reagents (glass beads, diatomite, kaolin and magnetic bar) were 20.4-4.5 IU/min, 27.4-6.9 IU/min, 27.5-7.9 IU/min and 7.8-0.1 IU/min respectively and an linear relationship was observed between the CR values and dalteparin concentrations (P < 0.05). The values of ACT were 173-615 seconds, 130-270 seconds, 123-226 seconds, 337-1411 seconds respectively, which showed a linear regression between the ACT values and dalteparin concentrations (P < 0.01). Differences in slope of the regression curves of ACT were observed with all the reagents tested (glass beads 248.2 s/IU, diatomite 74.8 s/IU, kaolin 58.2 s/IU and magnetic bar 1112.2 s/IU, P < 0.01). While the minimum concentration of dalteparin was 0.2 IU/ml, 0.4 IU/ml, 1.4 IU/ml and 0.2 IU/ml separately, the ACT values of the four coagulants (glass beads, diatomite, kaolin and magnetic bar) were beyond the normal limit and showed a noticeable increase respectively (P < 0.01).

CONCLUSIONSThis study showed that there was an excellent linear relationship between the CR and ACT values and dalteparin concentrations for all the four reagents (glass beads, diatomite, kaolin and magnetic bar) in vitro. The sensitivity of different coagulation reagents to LMWH different. Choosing a suitable reagent, both CR and ACT were possible to be used as a convenient bedside test for LMWH.

Adult ; Anticoagulants ; pharmacology ; Blood Coagulation ; drug effects ; Blood Coagulation Tests ; Female ; Heparin, Low-Molecular-Weight ; pharmacology ; Humans ; Male ; Middle Aged

OBJECTIVETo investigate the effect of the anticoagulants on PRP quality, so as to clarify the appropriate anticoagulant used in PRP production.

METHODSThe microstructure change of platelets collected via heparin, citrate, acid citrate dextrose (ACD) and citrate-theophylline-adenosine-dipyridamole ( CTAD) was observed by TEM following time course. The extent of spontaneous activation of platelets in four groups was detected by measuring sP-selectin in plasma. The TGF-β1 release amount of activated PRP of four groups was measured.

RESULTSCTAD is superior to other anticoagulants in maintaining the integrity of platelet structures for a long time and preventing platelet spontaneous activation. ACD slightly surpassed heparin and citrate in above two aspects. ACD-PRP and CTAD-PRP released significantly more TGF-β1 compared with heparin and citrate.

CONCLUSIONSThe PRP quality and biological effects were strongly associated with the type of Anticoagulants. ACD and CTAD are optimal anticoagulants in PRP production for they can maintain platelet viability at a high level.

Adenosine ; pharmacology ; Anticoagulants ; pharmacology ; Blood Platelets ; drug effects ; physiology ; Citrates ; pharmacology ; Citric Acid ; pharmacology ; Dipyridamole ; pharmacology ; Drug Combinations ; Glucose ; analogs & derivatives ; pharmacology ; Heparin ; pharmacology ; Platelet Activation ; drug effects ; Platelet-Rich Plasma ; Theophylline ; pharmacology ; Transforming Growth Factor beta1 ; metabolism

BACKGROUND/AIMS: Short hemofilter survival and anticoagulation-related life-threatening complications are major problems in systemic anticoagulation with heparin (SAH) for continuous renal replacement therapy (CRRT). The present study examined if regional anticoagulation with citrate (RAC) using commercially available solutions can overcome the associated problems of SAH to produce economical benefits. METHODS: Forty-six patients were assigned to receive SAH or RAC. We assessed the coagulation state, clinical outcomes, and adverse events. A Kaplan-Meier analysis was used to estimate hemofilter life span. The economical benefit related to the prolonged hemofilter survival was examined on the basis of the average daily cost. RESULTS: The mean age of patients was 66.5 +/- 13.8 years and the majority were male (60.9%). While elective discontinuation was most common cause of early CRRT interruption in the RAC group (34.3%, p < 0.01), hemofilter clotting was most prevalent in the SAH group (82.2%, p < 0.01). The patient metabolic and electrolyte control and survival rate were not different between the two groups. When compared with the RAC group, the anticoagulation-associated bleeding was a major complication in the SAH group (15.0% vs. 61.5%, p < 0.01). Regional anticoagulated hemofilters displayed a significantly longer survival time than systemic anticoagulated hemofilters (59.5 +/- 3.8 hr vs. 15.6 +/- 1.3 hr, p < 0.01). Accordingly, the mean daily continuous venovenous hemodiafiltration costs in the RAC and SAH groups were $575 +/- 268 and $1,209 +/- 517, respectively (p < 0.01). CONCLUSIONS: RAC prolonged hemofilter survival, displaying an economical benefit without severe adverse effects. The present study therefore demonstrates that RAC, using commercially available solutions, may be advantageous over SAH as a cost-effective treatment in CRRT.
Adult ; Aged ; Anticoagulants/*pharmacology ; Citric Acid/*pharmacology ; Critical Illness ; Female ; Health Care Costs ; *Hemodiafiltration/adverse effects/economics/mortality ; Heparin/*pharmacology ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged

OBJECTIVETo observe the effects of recombinant human epidermal growth factor (rhEGF) on deep partial thickness burn wound healing.

METHODSThe rats were inflicted with deep partial thickness burn. The wounds were either treated with rhEGF, rhEGF with heparin or isotonic saline, respectively. Wound healing time was observed. Wound healing rate, water content and hydroxyproline (OHP) content and type I/III collagen ratio in the wound tissue were determined. Cellular DNA cycle analysis and histological examination were processed.

RESULTSAfter the application of rhEGF, burn wound healing time was shortened by two days and wound content of OHP was increased (P < 0.05), with decreased collagen type I/III ratio (P < 0.05). As a result, granulation was enhanced and cellular DNA replication was accelerated (P < 0.05). Heparin addition could augment the effects of rhEGF, especially on wound healing time (2 days shorter) and granulation.

CONCLUSIONThe wound healing time of the deep partial thickness burn could be accelerated markedly by topical application of rhEGF, but early application did not show obvious effects. The addition of heparin might further accelerate wound healing.

Animals ; Burns ; drug therapy ; pathology ; Epidermal Growth Factor ; pharmacology ; Epithelial Cells ; pathology ; Female ; Heparin ; pharmacology ; Humans ; Male ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology ; Wound Healing ; drug effects

Based on non-enzymatic protein glycated reaction, the sodium periodate-oxidated low molecular weight heparin-antithrombin covalent complex (SPLMWATH) was produced. By using polyethyleneimine-glutaraldehyde bonding technique, polyvinyl chloride (PVC) tubings were coated with SPLMWATH, heparin and low molecular weight heparin (LMWH). Spectrophotometry and dynamic clotting time experiment were used to determine the synthetic ratio of SPLMWATH, graft density, coating leaching ratio and to evaluate the antithrombogenicity of different coating on the PVC tubings. The results showed that the synthetic ratio of SPLMWATH was approximately 55%, and compared with heparin coating and LMWH coating, the graft density of SPLMWATH coating on the PVC tubing was smaller, but its coating stability and antithrombogenicity were significantly better than that of heparin coating and LMWH coating on the PVC tubings.
Anticoagulants ; chemical synthesis ; pharmacology ; Coated Materials, Biocompatible ; chemical synthesis ; pharmacology ; Extracorporeal Circulation ; instrumentation ; Heparin, Low-Molecular-Weight ; chemistry ; pharmacology ; Humans ; Polyvinyl Chloride ; chemistry ; Surface Properties