1. |
- Abusibaa, W. A., et al.
(författare)
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Expression of the GBGT1 Gene and the Forssman Antigen in Red Blood Cells in a Palestinian Population
- 2019
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Ingår i: Transfusion Medicine and Hemotherapy. - : S. Karger AG. - 1660-3796 .- 1660-3818. ; 46:6, s. 450-454
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Tidskriftsartikel (refereegranskat)abstract
- Background: The Forssman antigen (FORS1 Ag) is expressed on human red blood cells (RBCs). We investigated its presence on RBCs from Palestinian subjects and Swedish subjects by serological testing and by sequencing part of exon 7 of the GBGT1 gene, which encodes Forssman synthase. -Materials and Methods: Blood samples from Palestinian subjects (n = 211 adults and n = 73 newborns) and from Swedish subjects (n = 47 adults) were analyzed in the study. RBCs from the Palestinian samples were typed for the FORS1 Ag using a monoclonal anti-Forssman antibody. The GBGT1 gene was genotyped by DNA sequencing (all adult samples) or by using amplification refractory mutation system PCR (newborn samples). Results: All of the studied samples were negative for the FORS1 Ag by serologic typing. DNA sequencing of the 3′ end of exon 7 of the GBGT1 gene, which includes Arg296, showed that all samples had the wild-type Arg296 sequence, which is associated with an inactive form of Forssman synthase. We detected four single nucleotide polymorphisms in the adult samples; two were silent (p.Tyr232=, p.Gly290=), and two were missense (p.Arg243Cys, p.Arg243His). The allele frequencies ranged from 0.2 to 3.6%. The p.Arg243Cys SNP was a novel SNP that was detected in one Palestinian sample. Conclusion: Our results confirmed the allelic diversity of GBGT1 and identified a novel nucleotide polymorphism in this gene, p.Arg243Cys. Our results also confirmed that the FORS blood group system is a low-frequency system. © 2019 S. Karger AG, Basel. Copyright: All rights reserved.
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2. |
- Andersson Shams Hakimi, Caroline, et al.
(författare)
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Effects of fibrinogen and platelet supplementation on clot formation and platelet aggregation in blood samples from cardiac surgery patients.
- 2014
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Ingår i: Thrombosis research. - : Elsevier BV. - 1879-2472 .- 0049-3848. ; 134:4, s. 895-900
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Tidskriftsartikel (refereegranskat)abstract
- Bleeding after cardiac surgery may be caused by surgical factors, impaired haemostasis, or a combination of both. Transfusion of blood products is used to improve haemostasis, but little is known about what combination is optimal. We hypothesized that addition of both fibrinogen and platelets to blood samples from cardiac surgery patients would improve clot formation and platelet aggregation to a greater extent than if the components were added separately.
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3. |
- Andersson Shams Hakimi, Caroline, et al.
(författare)
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Effects of fibrinogen and platelet transfusion on coagulation and platelet function in bleeding cardiac surgery patients.
- 2019
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Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 63:4, s. 475-482
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Tidskriftsartikel (refereegranskat)abstract
- Excessive bleeding is a significant problem in cardiac surgery. Fibrinogen and platelet concentrate transfusion are used clinically to improve haemostasis and reduce bleeding but little is known about their functional effects on coagulation and platelet function in patients with ongoing bleeding.Forty-two patients with ongoing bleeding after cardiac surgery were included in an observational study. Patients received either fibrinogen concentrate (n=16), platelet concentrate (n=12), or both fibrinogen and platelets (n=14), median doses 2g fibrinogen and 2 units platelets given at one occasion. Blood samples were collected before and after transfusion. Coagulation (clotting time and clot stability) was analysed with rotational thromboelastometry, and platelet function with impedance aggregometry. In addition, platelet count and fibrinogen concentration was measured. Chest drain output was measured before and after the transfusion.Fibrinogen infusion resulted in an increase in fibrinogen concentration and clot stability (P=0.001), but had no effect on platelet aggregation. Platelet transfusion did not significantly affect coagulation, but improved arachidonic acid- and TRAP-induced platelet aggregation (P=0.017 and 0.034 respectively) and increased platelet count. Combined fibrinogen and platelet transfusion shortened clotting time (P=0.005) and increased clot stability (P=0.001), and improved arachidonic acid- and TRAP-induced platelet aggregation (P=0.004 and 0.016 respectively), and increased fibrinogen concentration and platelet count. The median bleeding volume was 150 (25th-75th percentile 70-240)mL/h before, and 60 (40-110)mL/h after transfusion of fibrinogen and/or platelet concentrate (P<0.001).The results demonstrate improved coagulation and platelet function following fibrinogen and platelet transfusion in patients bleeding after cardiac surgery.
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4. |
- Andersson Shams Hakimi, Caroline, et al.
(författare)
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In vitro assessment of platelet concentrates with multiple electrode aggregometry.
- 2015
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Ingår i: Platelets. - : Informa UK Limited. - 0953-7104 .- 1369-1635. ; 26:2, s. 132-137
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT Storage impairs platelet function. It was hypothesized that multiple electrode aggregometry in vitro could be used to follow aggregability in platelet concentrates over time and that the results predict the efficacy of platelet transfusion in an ex vivo transfusion model. In vitro platelet aggregability was assessed in apheresis and pooled buffy coat platelet concentrates (BCs) (n = 13 each) using multiple electrode aggregometry with different agonists 1, 3, 5 and 7 days after preparation. In the ex vivo transfusion model, whole blood samples from nine healthy volunteers were collected every second day. The samples were supplemented with stored platelets (+146 × 10(9) × l(-1)) from the same unit 1, 3, 5 and 7 days after preparation. Platelet aggregability was assessed in the concentrate and in the whole blood samples before and after platelet supplementation. There was a continuous reduction in in vitro platelet aggregability over time in both apheresis and pooled BCs. The same pattern was observed after ex vivo addition of apheresis and pooled BCs to whole blood samples. The best correlation between in vitro aggregability and changes in aggregation after addition was achieved with collagen as agonist (r = 0.67, p
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5. |
- Andersson Shams Hakimi, Caroline, et al.
(författare)
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The Effect of Ex Vivo Factor XIII Supplementation on Clot Formation in Blood Samples From Cardiac and Scoliosis Surgery Patients.
- 2018
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Ingår i: Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis. - : SAGE Publications. - 1938-2723. ; 24:4, s. 677-683
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Tidskriftsartikel (refereegranskat)abstract
- Excessive perioperative bleeding remains a substantial problem. Factor XIII (FXIII) contributes to clot stability, and it has therefore been suggested that supplementation with FXIII concentrate may improve perioperative hemostasis. We evaluated the effects of increasing doses of FXIII, alone or in combination with fibrinogen or platelet concentrate, in blood samples from 2 considerably different groups of surgical patients: cardiac and scoliosis surgery patients. Whole-blood samples were collected immediately after operation from cardiac and scoliosis surgery patients. The samples were supplemented with 3 clinically relevant doses of FXIII concentrate (+20%, +40%, and +60%), alone or in combination with a fixed dose of fibrinogen concentrate (+1.0 g/L) or fresh apheresis platelets (+92 × 10(9)/L). Clot formation was assessed with rotational thromboelastometry (ROTEM). When the highest dose of FXIII concentrate was added, EXTEM clotting time was shortened by 10% in both cardiac and scoliosis surgery patients (95% confidence intervals: 2.4%-17% and 3.3%-17%, respectively), and FIBTEM maximum clot firmness was increased by 25% (9.3%-41%) in cardiac patients, relative to baseline. When fibrinogen was added, the dose-dependent effect of FXIII on clot stability was maintained, but the total effect was markedly greater than with FXIII alone, +150% (100%-200%) and +160% (130%-200%) for the highest FXIII dose in cardiac and scoliosis patients, respectively. Ex vivo supplementation with clinically relevant doses of FXIII improved clot formation moderately in blood samples from cardiac and scoliosis surgery patients, both alone and when given in combination with fibrinogen or platelet concentrate.
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7. |
- Blennow, Kaj, 1958, et al.
(författare)
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No association between the alpha2-macroglobulin (A2M) deletion and Alzheimer's disease, and no change in A2M mRNA, protein, or protein expression.
- 2000
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Ingår i: Journal of neural transmission (Vienna, Austria : 1996). - : Springer Science and Business Media LLC. - 0300-9564 .- 1435-1463. ; 107:8-9, s. 1065-79
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Tidskriftsartikel (refereegranskat)abstract
- A polymorphism consisting of a deletion near the 5' splice site of exon 18 on the alpha2-macroglobulin (A2M) gene (A2M-2) has been suggested to be associated with Alzheimer's disease (AD) in family-based studies. We studied the A2M-2 allele together with the ApoE alleles in a large series on patients with AD (n = 449) and age-matched controls (n = 349). Neuropathologically confirmed diagnoses were available in 199 cases (94 AD and 107 control cases). We found no increase in A2M-2 genotype or allele frequencies in AD (27.5% and 14.6%) versus controls (26.4% and 14.9%). In contrast, a marked increase (p < 0.0001) in ApoE epsilon4 genotype or allele frequencies was found in AD (66.6% and 41.2%) as compared with controls (29.8% and 16.5%), suggesting sufficient statistical power in our sample. No relation was found between the A2M-2 and the ApoE epsilon4 allele. No change in A2M exon 17-18 mRNA size or sequence or A2M protein size was found in cases carrying the A2M-2 deletion, suggesting that there is no biological consequences of the A2M intronic deletion. No change in A2M protein level in cerebrospinal fluid was found in AD, suggesting that the A2M-2 allele does not effect the A2M protein expression in the brain. The lack of an association between the A2M-2 allele and AD in the present study, and the lack of abnormalities in the A2M mRNA or protein suggest that the A2M-2 allele is not associated with AD.
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8. |
- Carlberg, Niclas, et al.
(författare)
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Circulating concentrations of glycocalyx degradation products in preeclampsia
- 2022
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Ingår i: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Background and Objectives: Preeclampsia is a multisystem disorder that affects maternal endothelium. The glycocalyx lines and protects the endothelial surface. In severe systemic diseases, like sepsis, it is shed and glycocalyx degradation products can be detected in increased concentrations in plasma. The aim of this study was to compare circulating concentrations of glycocalyx degradation products in degrees of preeclampsia severity. Study design: In this observational study, we included women from the South African PROVE biobank. Women were divided into normotensive controls, women with preeclampsia without end-organ complications, women with a single end-organ complication and women with multiple end-organ complications. Plasma samples taken at inclusion after diagnosis (preeclampsia cases) or at admission for delivery (normotensive controls) were analyzed with ELISA for syndecan-1, hyaluronic acid and thrombomodulin and compared between groups. Results: Women with preeclampsia (n = 47) had increased plasma concentrations of hyaluronic acid (100.3ng/ml IQR 54.2–204 vs. 27.0ng/ml IQR (13.5–66.6), p < 0,001) and thrombomodulin (4.22ng/ml IQR 3.55–5.17 vs. 3.49ng/ml IQR 3.01–3.68, p = 0.007) but not syndecan-1 compared with normotensive women (n = 10). There were no differences in plasma concentration in any of these biomarkers in women with preeclampsia with no end-organ complications (n = 10) compared with women with preeclampsia and one end-organ complication (n = 24). Women with preeclampsia with two or more end-organ complications (n = 13) had increased plasma concentrations of thrombomodulin (5.46ng/ml, IQR 4.85–7.83 vs. 4.66ng/ml, IQR 3.45–4.88, p = 0.042) compared with women with preeclampsia and no end-organ complications. Conclusion: Thrombomodulin was associated with disease severity and may be valuable for risk-stratifying women with preeclampsia.
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9. |
- Damén, Tor, et al.
(författare)
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Atrial natriuretic peptide does not degrade the endothelial glycocalyx: A secondary analysis of a randomized porcine model
- 2021
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 65:9, s. 1305-1312
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Tidskriftsartikel (refereegranskat)abstract
- Background: The atrial natriuretic peptide (ANP) released from the heart regulates intravascular volume and is suspected to increase capillary permeability. Contradictory results regarding ANP and glycocalyx degradation have been reported. The aim of this study was to investigate if an infusion of ANP causes degradation of the endothelial glycocalyx. Methods: Twenty pigs, pretreated with 250mg methylprednisolone, were randomized to receive an infusion of either ANP (50ng/kg/min) (n=10) or 0.9% NaCl (n=10) during 60min. Endothelial glycocalyx components (heparan sulphate proteoglycan and hyaluronic acid), Hct, calculated plasma volume and colloid osmotic pressure were measured from baseline to 60min. Results: There was no difference between the control and intervention groups for heparan sulphate proteoglycan and hyaluronic acid corrected for the change in plasma volume (P=.333 and 0.197). Hct increased with 1.8±2.2% in the intervention group (P=.029) with no change −0.5±2.3% in the control group (P=.504). The plasma volume decreased in the intervention group with −8.4±10% (P=.034) with no change in the control group 3.1±12% (P=.427). Median changes in colloid osmotic pressures in the control and intervention group were −0.39 [95% CI, −1.88-0.13] and 0.9 [95% CI, 0.00-1.58], respectively (P=.012). Conclusions: In this randomized porcine study, an ANP infusion did not cause endothelial glycocalyx degradation but decreased the plasma volume most probably due to precapillary vasodilation and increased filtration. © 2021 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd
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10. |
- Damén, Tor, et al.
(författare)
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Effects of different mean arterial pressure targets on plasma volume, ANP and glycocalyx-A randomized trial.
- 2021
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Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 65:2, s. 220-227
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Tidskriftsartikel (refereegranskat)abstract
- Arterial haematocrit (Hct) has been shown to decrease after anaesthesia induction, most probably because of an increased plasma volume (PV). The primary objective was to quantify change in PV if mean arterial pressure (MAP) was kept at baseline level or allowed to decrease to 60mm Hg. Our secondary objective was to evaluate underlying mechanisms of this response.Twenty-four coronary artery bypass patients were randomized to a higher (90mm Hg, intervention group) or lower (60mm Hg, control group) MAP by titration of norepinephrine. During the experimental procedure, no fluids were administered. Baseline PV was measured by 125 I-albumin and the change in PV was calculated from the change in Hct. Changes in MAP, plasma 125 I-albumin, colloid osmotic pressure, albumin, Mid Regional-pro Atrial Natriuretic Peptide (MR-proANP) and endothelial glycocalyx components were measured from baseline to 50minutes after anaesthesia induction.The MAP during the trial was 93±9mm Hg in the intervention group and 62±5mm Hg in the control group. PV increased with up to 420±180mL in the control group and 45±130mL in the intervention group (P<.001). Albumin and colloid osmotic pressure decreased significantly more in the control group. MR-proANP increased in the control group but no shedding of the glycocalyx layer was detected in either of the groups.Allowing mean arterial pressure to fall to 60mm Hg during anaesthesia induction, increases the plasma volume due to reabsorption of interstitial water, with no ANP-induced degradation of the endothelial glycocalyx.
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