Does dietary arsenic and mercury affect cutaneous bleeding time and blood lipids in humans?

1994 ◽  
Vol 46 (1-2) ◽  
pp. 135-153 ◽  
Author(s):  
Helle M. Meltzer ◽  
Håvard H. Mundal ◽  
Jan Alexander ◽  
Karen Bibow ◽  
Trond A. Ydersbond
1983 ◽  
Vol 50 (02) ◽  
pp. 543-546 ◽  
Author(s):  
J Z Mortensen ◽  
E B Schmidt ◽  
A H Nielsen ◽  
J Dyerberg

SummaryDiverging results from studies of marine oil supplementation to western diets initiated the undertaking of a double-blind crossover study, with administration to healthy volunteers for 4 weeks of either 10 g of fish oil or 10 g of vegetable oil. Each oil containing approx. 40% of n-3 and n-6 polyunsaturated fatty acids (PUFA) respectively. During the n-3 PUFA period, systolic blood pressure, plasma total lipids, triglycerides and VLDL concentrations fell significantly whereas plasma antithrombin-III (AT-III) rose. Cutaneous bleeding time increased significantly. In contrast only AT-III rose during the n-6 PUFA feeding, however, more marked than during the n-3 oil period. It is concluded that a n-3 PUFA oil supplement to the western diet exerts an effect that generally is considered as beneficial in terms of the risk of developing cardiovascular diseases. It is in this respect superior to that of n-6 PUFA, stressing the necessity of a more differentiated approach to advices on dietary PUFA enrichment than presently is exerted.


1981 ◽  
Vol 61 (3) ◽  
pp. 317-324 ◽  
Author(s):  
T. A. B. Sanders ◽  
Marguerite Vickers ◽  
A. P. Haines

1. Twelve healthy male subjects took a daily supplement of 20 ml of cod-liver oil for 6 weeks. This provided 1.8 g of eicosapentaenoic acid (20:5ω3) and 2.2 g of docosahexaenoic acid (22:6ω3). The effects of the supplement on blood lipids, haemostatic variables, bleeding time and plasma vitamin A and carotene were studied. In seven subjects platelet aggregation induced by adenosine 5′-pyrophosphate (ADP) was also studied. 2. The proportions of 20:5ω3 and 22: 6ω3 in platelet and erythrocyte phosphoglycerides were substantially increased by the supplement mainly at the expense of ω6 polyunsaturated fatty acids. 3. Mean plasma triglyceride concentrations were reduced and those of high-density-lipoprotein (HDL) cholesterol were increased by the supplement. 4. The mean bleeding time was significantly prolonged after 3 weeks of taking the supplement, but had returned to the presupplementation value 5 weeks after withdrawal of the supplement. 5. The maximum estimated response to platelet aggregation induced by ADP was increased by the supplement. 6. The mean levels of antithrombin III (immunological) and blood pressure were lower at the end of the period of supplementation and remained so 5 weeks after withdrawal of the supplement. No significant changes in other variables were noted.


1995 ◽  
Vol 48 (1) ◽  
pp. 118-118
Author(s):  
Helle M. Meltzer ◽  
Håvard H. Mundal ◽  
Jan Alexander ◽  
Karen Bibow ◽  
Trond A. Ydersbond

VASA ◽  
2005 ◽  
Vol 34 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Brunner-La Rocca ◽  
Schindler ◽  
Schlumpf ◽  
Saller ◽  
Suter

Background: Previous studies showed an anti-atherosclerotic effect of PADMA 28, an herbal formula based on Tibetan medicine. As the mechanisms of action are not fully understood, we investigated whether PADMA 28 may lower blood lipids and lipid oxidisability, and affect early endothelial dysfunction. Patients and methods: Sixty otherwise healthy subjects with total cholesterol ≥5.2 mmol/l and < 8.0 mmol/l were randomly assigned to placebo or PADMA 28, 3 x 2 capsules daily, for 4 weeks (double-blind). Blood lipids (total, LDL-, and HDL-cholesterol, triglycerides, Apo-lipoprotein A1 and B) and ex vivo lipid oxidisability were measured before and after treatment. In a subset of 24 subjects, endothelial function was assessed using venous occlusion plethysmography with intraarterial infusion of acetylcholine. Isolated LDL and plasma both untreated and pre-treated with PADMA 28 extract were oxidised by the radical generator AAPH. Conjugated diene formation was measured at 245 nm. Results: Blood lipids did not change during the study in both groups. In contrast to previous reports in mild hypercholesterolaemia, no endothelial dysfunction was seen and, consequently, was not influenced by therapy. Ex vivo blood lipid oxidisability was significantly reduced with PADMA 28 (area under curve: 5.29 ± 1.62 to 4.99 ± 1.46, p = 0.01), and remained unchanged in the placebo group (5.33 ± 1.88 to 5.18 ± 1.78, p > 0.1). This effect persisted one week after cessation of medication. In vitro experiments confirmed the prevention of lipid peroxidation in the presence of PADMA 28 extracts. Persistent protection was also seen for LDL isolated from PADMA 28-pretreated blood after being subjected to rigorous purification. Conclusions: This study suggests that the inhibition of blood lipid oxidisability by PADMA 28 may play a role in its anti-atherosclerotic effect.


Phlebologie ◽  
2008 ◽  
Vol 37 (06) ◽  
pp. 287-297 ◽  
Author(s):  
P.-M. Baier ◽  
Z. T. Miszczak

Summary Background: Platelet function inhibitors (PFI) are used for prophylaxis of atherothrombosis. These drugs cause a prolongation of the bleeding time and should eventually be stopped before an elective operation. However, there is a risk that a perioperative pause of PFI lead to acute atherothrombosis. Objective: Our aim was to study whether a discontinuation of PFI therapy is necessary to avoid bleeding complications in patients undergoing varicose vein surgery. Methods: Selective review of the literature and retrospective analysis of clinical data of our own patients. Results: In the years 2002 to 2007 a total of 10 827 patients have been operated on varicose veins, 673 (6.2%) of these aged 32–86 years (67 ± 7.9) receiving permanent PFI therapy: 256 male patients (38.0%) and 417 female (62.0%), 39.1% categorized as ASA III patients: male 11.6%, female 27.5%. 38 patients who continued PFI therapy did not demonstrate haemorrhagic complications and none of those pausing anti-platelet medication experienced thromboembolic complications. The literature survey confirmed our finding that it is not necessary to suspend PFI medication for varicose vein surgery as the bleeding risk can be controlled for by technical means. Conclusion: Discontinuation of PFI therapy prior to interventions on varicose veins does not seem to be necessary, further studies are essential though.


1988 ◽  
Vol 59 (02) ◽  
pp. 225-230 ◽  
Author(s):  
J P Maffrand ◽  
A Bernat ◽  
D Delebassée ◽  
G Defreyn ◽  
J P Cazenave ◽  
...  

SummaryThe relative importance of ADP, arachidonic acid metabolites and serotonin as thrombogenic factors was evaluated in rats by comparing, after oral administration, the effects of two inhibitors of ADP-induced platelet aggregation (ticlopidine and PCR 4099), three cyclo-oxygenase inhibitors (aspirin, triflusal and indobufen) and a selective serotonin 5HT2 receptor antagonist (ketanserin) on platelet aggregation, in four platelet-dependent thrombosis models and on bleeding time. Platelet aggregation induced by ADP and collagen was completely inhibited by ticlopidine and PCR 4099 whereas only the collagen aggregation was reduced by the cyclo-oxygenase inhibitors. Ketanserin or a depletion of platelet serotonin by reserpine did not affect platelet aggregation. Ticlopidine and PCR 4099 greatly prolonged rat tail transection bleeding time. This is probably related to their known ability to inhibit ADP-mediated platelet aggregation. In contrast, the cyclooxygenase inhibitors did not affect bleeding time at all. Reserpine and ketanserin prolonged bleeding time by interfering with the action of serotonin on the vascular wall. Ticlopidine and PCR4099 were very potent antithrombotics in all the models. Aspirin, only at a high dose, inhibited poorly thrombus formation on a silk thread in an arterio-venous shunt, suggesting that the inhibition of cyclo-oxygenase was not responsible. Triflusal was inactive in all models while indobufen slightly reduced thrombus formation in the silk thread and metallic coil models. Ketanserin and reserpine reduced thrombus only in the metallic coil model. Thrombus formation was greatly reduced in fawn-hooded rats, which lack ADP in their platelet dense granules because of a genetic storage pool deficiency. Taken together, the results obtained with the drugs and with the fawn-hooded rats support the concept that ADP plays a key role in thrombogenesis in rats.


1994 ◽  
Vol 71 (01) ◽  
pp. 095-102 ◽  
Author(s):  
Désiré Collen ◽  
Hua Rong Lu ◽  
Jean-Marie Stassen ◽  
Ingrid Vreys ◽  
Tsunehiro Yasuda ◽  
...  

SummaryCyclic Arg-Gly-Asp (RGD) containing synthetic peptides such as L-cysteine, N-(mercaptoacetyl)-D-tyrosyl-L-arginylglycyl-L-a-aspartyl-cyclic (1→5)-sulfide, 5-oxide (G4120) and acetyl-L-cysteinyl-L-asparaginyl-L-prolyl-L-arginyl-glycyl-L-α-aspartyl-[0-methyltyrosyl]-L-arginyl-L-cysteinamide, cyclic 1→9-sulfide (TP9201) bind with high affinity to the platelet GPIIb/IIIa receptor.The relationship between antithrombotic effect, ex vivo platelet aggregation and bleeding time prolongation with both agents was studied in hamsters with a standardized femoral vein endothelial cell injury predisposing to platelet-rich mural thrombosis, and in dogs with a carotid arterial eversion graft inserted in the femoral artery. Intravenous administration of G4120 in hamsters inhibited in vivo thrombus formation with a 50% inhibitory bolus dose (ID50) of approximately 20 μg/kg, ex vivo ADP-induccd platelet aggregation with ID50 of 10 μg/kg, and bolus injection of 1 mg/kg prolonged the bleeding time from 38 ± 9 to 1,100 ± 330 s. Administration of TP9201 in hamsters inhibited in vivo thrombus formation with ID50 of 30 μg/kg, ex vivo platelet aggregation with an ID50 of 50 μg/kg and bolus injection of 1 mg/kg did not prolong the template bleeding time. In the dog eversion graft model, infusion of 100 μg/kg of G4120 over 60 min did not fully inhibit platelet-mediated thrombotic occlusion but was associated with inhibition of ADP-induccd ex vivo platelet aggregation and with prolongation of the template bleeding time from 1.3 ± 0.4 to 12 ± 2 min. Infusion of 300 μg/kg of TP9201 over 60 min completely prevented thrombotic occlusion, inhibited ex vivo platelet aggregation, but was not associated with prolongation of the template bleeding time.TP9201, unlike G4120, inhibits in vivo platelet-mediated thrombus formation without associated prolongation of the template bleeding time.


1990 ◽  
Vol 64 (01) ◽  
pp. 117-120 ◽  
Author(s):  
Alessandra Casonato ◽  
M Teresa Sartori ◽  
Luigi de Marco ◽  
Antonio Girolami

SummaryWe have investigated the effects of 1-desamino-8-D-arginine vasopressin (DDAVP) infusion on platelet count and bleeding time in 4 patients with type IIB von Willebrand’s disease (vWd). Three of four patients showed a normalization of the bleeding time within 1 h after the infusion, while bleeding time was not modified in the fourth. In accordance with the literature, thrombocytopenia was observed after DDAVP infusion, but this thrombocytopenia was due to the anticoagulants used for blood collection. In two patients (F. I., G. F.) no thrombocytopenia was observed when platelets were counted by fingerstick method but there was a 20% platelet decrease in blood samples collected in sodium citrate and a 50% decrease in samples collected in EDTA. Dramatic falls in platelet counts (70–95%) were observed in the additional two patients (C. A., D.Z.) after DDAVP infusion, when both sodium citrate or EDTA were used as anticoagulants. In the latter two patients there was also a 50% decrease in platelet count when the fingerstick method was used. The decrease in the patient’s platelet count in EDTA samples after DDAVP infusion could be prevented, in part, by the previous additions of an anti GPIb monoclonal antibody and an anti GPIIb-IIIa monoclonal antibody.Thus, the thrombocytopenia observed in the four IIB vWd patients studied after DDAVP infusion seems to be, at least partially, a pseudothrombocytopenia depending on the calcium concentration in the blood samples and the availability of GPIb and GPIIb-IIIa receptors. These findings and the normalization of the bleeding time observed in three of the four patients has led us to reconsider the possible use of DDAVP in the treatment of our IIB vWd patients.


Sign in / Sign up

Export Citation Format

Share Document