Search PubMed⌕ Search

Biomedical subjects

M Blombäck

Publications and source records attributed to M Blombäck.

At least 19 recordsLinked to original sources
PubMed1998

Local vs. systemic immune and haemostatic response to hip arthroplasty.

Local and systemic immune and haemostatic responses were studied in 10 patients, aged 57-78 years, undergoing elective hip arthroplasty. Cytokines, soluble cytokine receptors, interleukin-1 receptor antagonist, soluble adhesion molecules, antithrombin, fibrin, soluble and fibrin D-dimer were analysed in wound drainage blood and in blood taken from the systemic circulation for up to 24 h post-operatively. Wound drainage blood concentrations of cytokines, interleukin-1 receptor antagonist and soluble cytokine receptors were increased compared with those in the systemic circulation except for the soluble interleukin-6 receptor. In wound drainage blood, soluble tumour necrosis factor receptors (P < 0.05), interleukin-1 receptor antagonist (P < 0.05) and interleukin-6 (P < 0.05-< 0.01) increased during the study period. In blood from the systemic circulation interleukin-6 increased (P < 0.05) while the soluble interleukin-6 receptor decreased (P < 0.05) compared with pre-operative values. Concentrations of soluble adhesion molecules did not change. Wound drainage blood showed marked hypercoagulation. After hip arthroplasty pro-inflammatory cytokines and their inhibitors were mainly confined to the local trauma site. A predominance for inhibitors was noted.

Aged↗
PubMed1998

A pharmacokinetic study of dalteparin (Fragmin) during late pregnancy.

Seventeen women with previously verified thromboembolism were included in a pharmacokinetic evaluation of dalteparin during the third trimester of pregnancy. The bioavailability of morning subcutaneous administration of dalteparin (crossover study) was also compared with that in the evening. Fifteen women injected themselves subcutaneously with 5000 IU and two with 2500 IU dalteparin once daily. An anti-FXa activity of 0.20-0.40 IU/ml 3 h after injection was obtained. The means +/- SD, when comparing morning and evening doses for 5000 IU, were: Cmax 0.21 +/- 0.05 and 0.20 +/- 0.05 IU anti-FXa/ml, AUC 0-24 h 1.97 +/- 0.46 and 1.93 +/- 0.55 IU x h/ml and tmax 3.71 +/- 0.89 and 4.32 +/- 1.60 h, respectively (NS). The two regimens were equivalent. A measurable anticoagulant effect was still observed 16 h after injection of 5000 IU dalteparin. The half-lives after a morning and an evening dose of 5000 IU dalteparin were 4.92 +/- 2.80 and 3.87 +/- 1.15 h, respectively (NS). There were no changes in thrombin marker levels during the two pharmacokinetic measurements.

Adult↗
PubMed1998

Thromboprophylaxis with low molecular mass heparin, 'Fragmin' (dalteparin), during pregnancy--a longitudinal safety study.

Twenty-five women with previous verified thromboembolic complications were treated with delteparin (Fragmin) during pregnancy and puerperium. Women with known hereditary thrombophilia (antithrombin, protein C and protein S deficiencies) or with phospholipid antibodies were excluded. The dose at entry was calculated according to body weight and thereafter monitored by anti-FXa activity aiming at 0.20-0.40 IU/ml plasma 3 h post injection. Dalteparin or dextran was used during delivery. Twenty-two women completed the study and 14 of these could be given the same dose throughout pregnancy. There was an increased dose response postpartum. There were no thromboembolic recurrences or severe bleeding complications. The level of antithrombin activity remained normal. Our thrombosis-prone pregnant women had initially increased levels of thrombin markers but no further increase was observed during the dalteparin thromboprophylaxis. Retrospectively, three heterozygous and three homozygous individuals for the FV Leiden mutation leading to activated protein C resistance were identified. In conclusion, dalteparin could safely be used as thromboprophylaxis during pregnancy in these thrombosis-prone women. Women weighing 50-79 kg at entry could be treated with 5000 IU of dalteparin once daily during pregnancy, without monitoring. Postpartum, many of the women were given a reduced dose.

Adult↗
PubMed1998

Coagulation factor V (Arg506-->Gln) mutation and early saphenous vein graft occlusion after coronary artery bypass grafting.

The factor V (Arg506-->Gln) mutation confers an increased risk of deep vein thrombosis, whereas its role in saphenous vein graft closure after coronary artery bypass grafting (CABG) remains unclear. This study examined the anticoagulant response to activated protein C (APC ratio) in relation to the surgical trauma and the significance of the factor V Leiden mutation in determining postoperative thrombin generation and fibrin formation and the risk of early vein graft occlusion. A total of 108 men undergoing elective CABG for exertional angina pectoris (mean age 61.1 +/- 8.7 years) were examined. The patency of saphenous vein grafts was studied at routine reangiography three months after CABG. Of 100 patients who underwent reangiography, 23 had one or more occluded vein grafts at reangiography. Heterozygosity for the factor V (Arg506-->Gln) mutation tended to be associated with early saphenous vein graft occlusion (5/11 carriers vs. 18/89 non-carriers with graft occlusion, chi2 = 3.52, p = 0.06), whereas pre- and postoperative APC ratios did not. Pre- and postoperative determinations of prothrombin fragment 1+2, thrombin-antithrombin complexes and soluble fibrin levels did not differ between patients with and without the mutation. Early saphenous vein graft occlusion after CABG could tentatively be added to deep vein thrombosis as a vascular complication that can be attributed to the factor V (Arg506-->Gln) mutation.

Aged↗
PubMed1997

Search for mutations in the genes for coagulation factors V and VIII with a possible predisposition to activated protein C resistance.

A total of 74 non-pregnant women with a previous episode of thrombosis were investigated for activated protein C (APC) resistance in the aPTT-based and factor IXa-X-based assays and for the presence of mutations in all APC-cleavage sites in the heavy chains of factor V and factor VIII. DNA fragments were amplified with the polymerase chain reaction (PCR) and those encoding for the Arg-306 and Arg-506 (factor V) and for Arg-740 (factor VIII) cleavage sites were subjected to restriction enzyme analysis. DNA fragments of 29 selected patients corresponding to the Arg-306 and Arg-679 cleavage sites in factor V, and to the Arg-336 and Arg-562 cleavage sites in factor VIII were sequenced. APC resistance was found in 40 cases, using the aPTT-based assay and in 35, using the factor IXa-X-based assay (23 patients were APC resistant in both assays), whereas 22 individuals had a normal response to APC. Forty-three patients carried Arg-506 to Gln mutation in factor V. No other polymorphism or mutation was found in the genes for factors V or VIII in the vicinity of the APC cleavage sites. It was concluded that the difference in response to APC in the two assays may not be explained by the presence of mutations in the APC cleavage sites of factor V and factor VIII in this group of patients. The data do not exclude the presence of mutations elsewhere in the factor V or factor VIII genes.

Adult↗
PubMed1997

Antithrombin III supplementation for patients undergoing PTCA for unstable angina pectoris. A controlled randomized double-blind pilot study.

BACKGROUND: Thrombin activation may be a higher risk for complications and restenosis after percutaneous transluminal coronary angioplasty in unstable patients than in patients with stable angina pectoris. The effects of heparin may be partly counteracted by a decrease in antithrombin (III). The primary objectives of this study were to evaluate whether a subnormal antithrombin level was associated with a hypercoagulable state and to evaluate the effects of antithrombin supplementation, before and after percutaneous transluminal coronary angioplasty, on biochemical signs of coagulation activation. Secondary objectives were to evaluate acute complications and restenosis rate at 3 months. METHODS: In a double-blind pilot study, 50 patients with unstable angina, with ongoing heparin infusion and with subnormal antithrombin levels (< 85%) were randomized to receive antithrombin supplementation or placebo. Treatment targeted to an antithrombin level of 120% was started with a 2h intravenous infusion before the percutaneous transluminal coronary angioplasty and was repeated, if there were further subnormal values, every 12th hour for 48 h. RESULTS: Angiographic success was 20/25 in the antithrombin group and 21/25 in the placebo group (ns). Abrupt closure occurred in two and one patients in the two groups, respectively. Activation of coagulation measured as elevations of prothrombin fragment 1+2, thrombin-antithrombin complexes and fibrin D-dimer was seen 2 days after the procedure. Baseline levels of fibrin D-dimer were 68 +/- 69 micrograms.l-1 in the antithrombin group vs 71 +/- 46 micrograms.l-1 in the placebo group (ns). Two days after percutaneous transluminal coronary angioplasty the levels increased to 135 +/- 103 vs 242 +/- 150 micrograms.l-1, respectively (P < 0.05 between the groups). Restenosis at 3 months occurred in 4/20 antithrombin patients and in 8/21 placebo patients (ns). CONCLUSIONS: In unstable angina patients with heparin treatment and subnormal antithrombin levels, anti-thrombin supplementation resulted in less activation of coagulation and a tendency towards less restenosis.

Angina, Unstable↗
PubMed1997

Acquired deficiency of antithrombin in association with a hypercoagulable state and impaired function of liver and/or kidney in preeclampsia.

To determine whether decreases in plasma antithrombin (AT) level, as seen in non-gestational acquired AT deficiency, result from a hypercoagulable state and/or liver/kidney damage, AT activity was measured in 24 uncomplicated and 30 preeclamptic women. The fifth percentile of AT levels in the normal pregnancies was used as a cut-off value to subdivide the preeclamptic patients into two groups. Markers of activated coagulation, i.e, levels of thrombin-antithrombin complex (TAT), fibrin D-dimer, soluble fibrin, von Willebrand factor (vWF) and platelet counts, were determined. Indicators of hepatic or renal function, i.e. concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, urinary albumin (U-albumin) and serum albumin (S-albumin), were assayed. AT levels were lower in those with preeclampsia than in the normal pregnancy group (P < 0.01). In the group with AT levels less than the cut-off point, levels of fibrin D-dimer (P < 0.05), soluble fibrin (P < 0.05), vWF (P < 0.05), ALT (P < 0.05), AST (P < 0.05), creatinine (P < 0.01) and U-albumin (P < 0.01) were increased, whereas platelet counts (P < 0.05) and S-albumin (P < 0.05) were decreased. All patients with ALT levels > 0.46 mu kat/1, AST > 0.58 mu kat/1, S-albumin < 23 g/1 and/or U-albumin > 4.9 g/24 h had AT levels < or = cut off. AT levels correlated with vWF (rs = - 0.73, P < 0.01) and creatinine (Rs = -0.70, P < 0.01). It is suggested that in preeclampsia, acquired AT deficiency is secondary to a hypercoagulable state, and/or associated with impaired hepatic and/or renal function.

Alanine Transaminase↗
PubMed1997

Variability of the response to activated protein C during normal pregnancy.

The response to activated protein C (APC) was investigated in 28 healthy women, non-carriers of the Arg506-Gln mutation in factor V, throughout pregnancy (gestation weeks 12, 20, 28, 32 and 37) and after the delivery. A suppression of APC response was observed which reached lowest values by week 28 (nAPC-ratio 0.78 +/- 0.13), sustained low up to the end of pregnancy and rose after delivery (1.11 +/- 0.22; P < 0.05). APC resistance (nAPC ratio < 0.75) was registered in 16 of the 28 women (57%). A reduction of APC ratio was directly related to its value in the non-pregnant state, being most pronounced in the women with the highest APC ratio. Factor VIII increased during pregnancy and correlated inversely to APC ratio (Z coefficient = -0.645, P < 0.0001). The correlation became weaker in the course of pregnancy, losing significance by week 32. This was explained by the differences in profiles of the two variables: the lowest measured APC ratio preceded the peak of factor VIII in most cases. The most pronounced rise of factor VIII was found in the women with minimal levels of APC ratio between 0.8 and 0.7. These results allowed us to speculate that APC response is closely regulated during pregnancy, aiming to maintain a certain relevant level. Transitory reduction of APC response is connected to factor VIII and discussed as a prevalent mechanism of functional APC resistance during pregnancy.

Adult↗
PubMed1997

Local wound and systemic coagulation/fibrinolysis responses in hip arthroplasty. Influence of allogeneic and autologous blood transfusion.

22 patients undergoing elective hip arthroplasty were studied. In 12 patients, a closed-loop autotransfusion system, without anticoagulant, was used and 10 had an ordinary wound drainage allowing repeated blood sampling from the wound. Plasma concentrations of antithrombin (AT), fibrin, soluble (SF) and fibrin D-dimer were determined preoperatively, 3, 8, and 24 hours after starting surgery. Wound drainage blood had increased concentrations of SF and fibrin D-dimer and decreased concentrations of AT compared to reference values and systemic concentrations in patients. Plasma concentrations of SF, fibrin D-dimer and AT did not differ between patients receiving retrieved blood and those receiving stored red blood cell concentrates (RBCs). Patients receiving blood transfusions had lower AT concentrations at 8 hours after starting surgery than those not receiving such a transfusion.

Aged↗
PubMed1997

The effect of progesterone on the haemostatic mechanism.

The hemostatic effect of progesterone administered vaginally at a dose of 100 mg twice a day throughout one menstrual cycle was investigated and compared with the coagulation factors in one untreated normal menstrual cycle in 15 women. The progesterone treatment resulted in a 20-fold progesterone rise in the early follicular phase from 1.2 nmol/l in the pretreatment control cycle to levels between 26 and 29 nmol/l during treatment. Ovulation was completely suppressed in seven women while eight women showed a slight rise in progesterone on treatment days 20 to 25 not compatible with the rise which could have been expected if ovulation had occurred. The effects found on haemostasis during progesterone treatment varied with the menstrual cycle and were so small that they could as well be due to chance and not to treatment.

Administration, Intravaginal↗
PubMed1997

Prediction of changes in levels of haemostatic variables during natural menstrual cycle and ovarian hyperstimulation.

To find if there is a relation between levels of haemostatic variables at low and high hormonal levels (oestradiol and progesterone) in an individual, blood samples were drawn from 12 women repeatedly during one menstrual cycle (Study I) and from 14 women undergoing in vitro fertilization, before hormonal stimulation and daily during the periovulatory period (Study II). Regression coefficients were calculated between minimum (independent) and maximum (dependent) values in both studies. In Study II highly significant regression coefficients were found between oestradiol minimum (pretreatment) and maximum (median 105 and 4730 pmol/l, respectively) for coagulation factors FVIII, von Willebrand Factor (antigen), FVII (activity and antigen), fibrinogen, protein C, protein S (free), antithrombin, plasminogen and plasminogen activator inhibitor-1; furthermore, between progesterone-minimum at day -3 or -2 (related to ovum pick up) and maximum (median 4.7 and 98 nmol/l, respectively) for FVIII, von Willebrand Factor, FVII (activity and antigen), protein C, protein S (free), and plasminogen. In Study I, where much lower hormonal levels were obtained at maximum (oestradiol median 297 pmol/l and progesterone 47 nmol/l), the same pattern was observed especially for FVII, FX, fibrinogen, plasminogen and plasmin inhibitor. Thus, the concentration of a haemostatic variable at a low oestradiol or progesterone level can predict the level at a high hormonal level.

Adult↗
PubMed1997

Combination of activated protein C resistance and antibodies to phospholipids in the development of thrombosis.

An insufficient response to activated protein C (APC) resistance and antibodies against phospholipids (PLa) are frequent laboratory findings associated with thrombosis. Studies investigating the coexistance of these two factors in thrombophilic patients and in patients with autoimmune disorders are summarized. The investigation of thrombophilic patients has revealed PLa in 35%. About half of these patients had a combination of PLa and APC resistance proved by the Arg506-Gln mutation in factor V (FV). A combination of APC resistance with PLa in this group of patients did not increase the risk of thrombosis recurrence. In the PLa-positive patients with autoimmune disorders having thrombosis in 10% to 56%, the incidence of the Arg506-Gln mutation in FV was significantly lower and varied between 2% and 9%. A known ability of PLa to induce APC resistance experimentally was often a reason to avoid the determination of APC response in PLa-positive patients. We suggest that PLa may play a dual role in the development of thrombosis in the carriers of the Arg506-Gln mutation in FV. On the one hand, PLas favor thrombosis by maintaining the APC response at a constantly low level. On the other hand, preventing the interaction of coagulation proteins on the phospholipid surface PLa may protect them from hypercoagulation.

Antibodies, Antiphospholipid↗
PubMed1997

Understanding von Willebrand's disease from gene defects to the patients.

von Willebrand's disease (vWD) is caused by qualitative (type 2) and quantitative (types 1 and 3) abnormalities of von Willebrand factor (vWF). vWD type 3, a severe form of the disease with nearly complete deficiency of the protein in plasma, are found to be homozygous or compound heterozygous for null mutations in the vWF gene. Null mutations in both alleles of the vWF gene completely disrupt the protein synthesis resulting in a nearly complete deficiency of the vWF in the type 3 patients. The vWD type 1 patients (mild form with partial deficiency of the protein) could be heterozygous for null mutations or compound heterozygous for the mutations (null mutation + missense mutation) in the gene. The vWD type 2, divided into four variants: types 2A, 2B, 2M and 2N, are caused exclusively by missense mutations within three different domains of the protein (gain or loss of function). The majority of type 2A mutations are located in the A2 domain and the types 2B and 2M mutations are in the A1 domain, while the type 2N mutation is in the FVIII binding domain.

Genotype↗
PubMed1997

A new approach to gene therapy.

Since 1975, different virus vectors have been developed in order to carry functional genes for gene transfer. However, no successful clinical trials have been reported so far. Recently, a new method for altering a single basepair of target DNA was reported using chimeric RNA/DNA oligonucleotides. The replacement of the single basepair in the target sequence can reach an efficacy of 20%. In patients with hemophilia A or B, the mutations (coagulation factors VIII and IX) are well characterized. The mutation-repair method using chimeric RNA/DNA oligonucleotides could provide an alternative for the treatment of hemophilia. The repaired cells will produce normal protein, like that of non-mutated cells, and the expression of the protein will be stable as long as the repaired cells survive. Clinically, by increasing the concentration of the functional protein (5-10%), it is hoped that a severe phenotype can be converted into a milder phenotype. The high replacement efficacy of the target sequence and the safety of the method make this a likely and promising approach for gene therapy in the future. However, no correction has been detected for the mutations in the coagulation factor genes factor genes factor IX and von Willebrand factor by this method so far.

Animals↗
PubMed1996

Properties and units in the clinical laboratory sciences. V. Properties and units in thrombosis and haemostasis: ISTH-IUPAC-IFCC recommendations 1995.

For historical reasons, the terms used in the nomenclature for properties in thrombosis and haemostasis differ according to 'school' of thought. This hampers communication. In collaboration, The Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis and the Committee (Commission) of Quantities and Units (in Clinical Chemistry) have prepared a set of recommended systematic names for properties in that domain. For use in electronic transmission each property has been given a code value.

Chemistry, Clinical↗
PubMed1996

On the value of menorrhagia as a predictor for coagulation disorders.

The value of menorrhagia as a predictor for mild bleeding disorders has been very little studied and the results are divergent. In the present study on 30 women with objectively verified menorrhagia, we found a significantly increased prevalence of von Willebrand's disease (20%). By keeping a strict sampling and laboratory routine, and by restricting sampling to cycle days 5-7, we also obtained a very low interindividual variation of von Willebrand factor and coagulation factor VIII. We conclude that menorrhagia is a valuable predictor for coagulation and platelet disorders, and that time of sampling is of importance. This should be considered in the investigation of menorrhagia, and can be a guideline in looking for mild bleeding disorders.

Adult↗
PubMed1996

Altered properties of the fibrin gel structure in patients with IDDM.

High plasma fibrinogen levels are associated with vascular complications in the general population. Fibrin, the structural element in a clot, is derived from fibrinogen by activation of thrombin. An abnormal fibrin gel structure has been demonstrated in patients with myocardial infarction and in diabetic patients during poor metabolic control. In the present study the properties of fibrin gel structure were investigated in 20 patients with insulin-dependent diabetes mellitus (IDDM): 10 patients without (age: 30 +/- 8; diabetes duration: 7 +/- 6 years), and 10 patients (age: 44 +/- 7; diabetes duration: 27 +/- 9 years) with microangiopathy. Fifteen healthy subjects served as controls (age: 40 +/- 8 years). The glycosylated haemoglobin level (HbA1c) was elevated (p < 0.001) in the patients: 6.5 +/- 1.5% in diabetic patients without, and 7.1 +/- 1.0% in diabetic patients with microangiopathy. C-reactive protein and plasma fibrinogen were similar as compared to healthy control subjects. The properties of the fibrin gel structure; i.e. the permeability coefficient (Ks) and the fibre mass length ratio (mu) formed in recalcified plasma on addition of thrombin were investigated. Ks was decreased in the diabetic patients, with (6.5 +/- 2.0 cm2; p < 0.01) and without microangiopathy (6.5 +/- 2.7 cm2; p < 0.05), as compared to healthy subjects (10.0 +/- 3.4 cm2), while mu was not significantly (p = 0.14) altered. The results indicate a lower fibrin gel porosity in patients with IDDM, despite normal plasma fibrinogen and irrespective of microangiopathy. The abnormal fibrin gel structure may be due to an increased glycosylation of the fibrin (-ogen) molecule caused by long-term hyperglycaemia and may be of importance for the development of angiopathy in diabetic patients.

Adult↗