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H C Godal

Publications and source records attributed to H C Godal.

At least 19 recordsLinked to original sources
PubMed1992

Does Lp(a) lipoprotein inhibit the fibrinolytic system?

Lp(a) lipoprotein contains a unique apolipoprotein, apolipoprotein (a), that has a striking homology with plasminogen. This homology has brought forward speculations as to an inhibitory effect of Lp(a) lipoproteins on fibrinolysis. The present investigation was undertaken to study the influence of Lp(a) lipoprotein on the fibrinolytic system. In an in vitro model, we have studied the influence of purified Lp(a) lipoprotein on plasminogen activation by tissue plasminogen activator (t-PA) in the presence of soluble fibrin. Increasing concentrations of Lp(a) lipoprotein (0-32 mg/dl) did not inhibit plasminogen activation by t-PA in the presence of thrombin or bathroxobin digested fibrinogen. When purified Lp(a) lipoprotein was added to whole blood, the degree of fibrin degradation obtained following standardized coagulation, as evaluated by the generation of D-dimer, was not reduced. D-dimer levels in plasma and in serum after standardized coagulation, as well as conventional parameters for evaluation of the fibrinolytic system, were determined in 10 individuals with high and 10 individuals with low levels of Lp(a) lipoprotein. No differences in the fibrinolytic parameters were observed between the groups. Thus, we found no evidence that Lp(a) lipoprotein interferes with the fibrinolytic process in the present experiments.

Amino Acid Sequence↗
PubMed1992

Fibrinolytic activity as a predictor of the outcome of prolapsed intervertebral lumbar disc surgery with reference to background variables: results of a prospective cohort study.

In a prospective study 122 patients with a slipped lumbar disc and no previous surgery were preoperatively examined for fibrinolytic activity. Surgical results for these patients were evaluated 12 months postoperatively by clinical overall assessment. In a multiple linear regression analysis fibrinolytic variables, euglobulin clot lysis time and plasminogen activator inhibitor 1, were shown to have predictive value regarding outcome of surgery; that is, normal fibrinolytic activity favors a satisfactory outcome and vice versa. Background variables and lipid profile were also recorded preoperatively. Body mass index, gamma-glutamyl transpeptidase, triglycerides and smoking were of statistical significance in relation to euglobulin clot lysis time and plasminogen activator inhibitor 1. Postoperative fibrinolytic re-examination of 20 patients seem to confirm that patients at risk of surgical failure have a prolonged depression of fibrinolytic activity.

Cohort Studies↗
PubMed1991

A novel principle for assessment of stimulated fibrinolysis.

After venous occlusion (VO), D-dimer levels were measured by means of an ELISA technique, in citrated plasma clotted by thrombin and in serum from whole blood. D-dimer levels increased with duration of incubation (30 min to 24 hours). D-dimer values, both in clotted plasma and in serum (n = 12), incubated 4 hours at room temperature, correlated well with euglobulin clot lysis time (ECLT) (r = -0.85 and -0.89, respectively, p less than 0.002) and tissue plasminogen activator (t-PA) activity, (r = 0.82 and 0.83, respectively, p less than 0.002). D-dimer concentrations from plasma and serum (n = 25) were compared (r = 0.90, p less than 0.001). Healthy volunteers (n = 65) were tested to establish reference values in serum from post-occlusive whole blood samples incubated 4 hours prior to centrifugation. Finally, a patient group (n = 62) was examined. For the whole material (n = 152) such D-dimer concentrations correlated well with both ECLT (r = -0.85, p less than 0.001) and t-PA activity (r = 0.81, p less than 0.001). D-dimer levels in serum were determined by a latex agglutination test as well. These semi-quantitative values also correlated significantly with both ECLT (r = -0.86, p less than 0.001) and t-PA activity (r = 0.87, p less than 0.001). We conclude that measurement of D-dimer as described above, represents a simple and accurate method for assessment of global fibrinolytic activity following VO. The latex agglutination test is particularly suitable as a screening procedure.

Adolescent↗
PubMed1991

The stimulatory effect of soluble fibrin on plasminogen activation by tissue plasminogen activator as studied by the Coa-set Fibrin Monomer test.

The stimulatory effect of various fibrin preparations on plasminogen activation by tissue plasminogen activator, was studied by the Coa-set Fibrin Monomer test (Kabi). Fibrin obtained by complete conversion of purified fibrinogen demonstrated a greater stimulatory effect on plasminogen activation than did equal amounts of fibrin obtained by partial conversion of fibrinogen. Soluble fibrin generated by treating human plasma with minute amounts of thrombin or bathroxobin, resembled partially converted purified fibrinogen. The plasminogen activating effect of completely converted fibrinogen was similar in thrombin and bathroxobin incubated samples. In preparations of partially converted fibrinogen and in plasma samples, bathroxobin digested fibrinogen expressed a more pronounced stimulatory effect on plasminogen activation than did thrombin digested specimens. The underlying mechanism for these differences are discussed.

Batroxobin↗
PubMed1991

Comparison of thrombin-antithrombin complex (TAT) levels and fibrinopeptide A following thrombin incubation of human plasma using hirudin as an inhibitor of TAT formation.

Following incubation of citrated plasma with human thrombin, the interaction of thrombin with antithrombin III was measured as thrombin-antithrombin complex (TAT) concentration. Comparison was made to thrombin activity on fibrinogen, assayed as fibrinopeptide A (FPA). Light scattering studies were included to evaluate polymerization of fibrin. Hirudin, at a final concentration of 100 U/ml, effectively inhibited TAT generation at final thrombin concentrations below 0.4 NIH U/ml. Hirudin by itself did not affect the TAT ELISA analysis. TAT and FPA values correlated closely (r = 0.83, p less than 0.001) and may equally well represent in vitro thrombin activity.

Antithrombin III↗
PubMed1990

Comparison of methods for detecting soluble fibrin in plasma. An in vitro study.

The ability of the COA-SET Fibrin monomer (COA-SET FM) test to detect soluble fibrin was evaluated by comparing the results of the COA-SET FM test with fibrinopeptide A (FPA) determinations following thrombin incubation of plasma or whole blood. In addition, two semiquantitative tests (erythrocytes-agglutination test (FM-test) and ethanol gelation test (EGT] were included in the study. Under the experimental conditions used, the COA-SET FM test proved less sensitive than the FPA-assay. There was a strong correlation between the results obtained by the two tests (r = 0.86, p = 0.0001). When solely regarding low levels of soluble fibrin, however, the correlation was weaker (r = 0.59, p = 0.0003). The FM-test was less sensitive than the COA-SET FM test, but more sensitive than EGT at normal and low fibrinogen concentrations. At high fibrinogen concentrations, however, EGT proved more sensitive than the FM-test. Knowing that 1-2 moles of FPA are released per mole of fibrin monomers formed, a discrepancy was observed between the FPA concentrations and the fibrin monomer concentrations as determined by the COA-SET FM test, the FPA levels being 2-25 times higher than the fibrin monomer levels. The discrepancy was greatest at incipient fibrinogen-fibrin transformation and at high plasma fibrinogen levels. This may suggest that fibrinogen in some way interfered with the stimulating effect of fibrin on the t-PA catalyzed activation of plasminogen, the principle upon which the COA-SET FM test is based.(ABSTRACT TRUNCATED AT 250 WORDS)

Ethanol↗
PubMed1987

The influence of pH on heat denaturation of anti-haemophilic cryoprecipitate.

The influence of pH on heat denaturation of anti-haemophilic cryoprecipitate (CP) was studied by using phosphate and citrate buffers at three different pH levels for processing lyophilized, heat treated CP. The solubility and the content of FVIII:C and fibrinogen were determined following heating at 68 degrees C for 24 hours and compared to "ordinary", non-heated CP. Both the solubility and the biological activity were best preserved in the most acidic samples (pH 5.7-6.7), these batches equalled non-heated CP. At higher pH, heat treatment resulted in reduced solubility and a more pronounced loss of FVIII:C and fibrinogen. Amino acids (Syntamin 17) have previously been shown to stabilize CP during heat treatment. Some of the stabilizing effect seems to be due to a large buffering capacity, maintaining a low pH during lyophilization and heating. Raising the pH level in Syntamin-CP from 6.6 to 7.8 resulted in decreased solubility and FVIII:C content. The quality of heat treated, acidic Syntamin-CP was comparable to that of heated, acidic phosphate- and citrate-CP. We conclude that buffers used for processing heat treated CP should be of low pH, and that acidic buffers may replace Syntamin without lowering the quality of the heated product.

Amino Acids↗
PubMed1987

Characteristics of a heat treated antihaemophilic cryoprecipitate.

In order to evaluate the influence of heat treatment (68 degrees C for 24 or 72 hours) on the essential components of antihaemophilic cryoprecipitate, i.e. factor VIII coagulant activity (VIII:C), von Willebrand factor (VIIIR:Ag and VIIIR:RCF) and fibrinogen, ordinary lyophilized cryoprecipitate was compared to heat treated, aminoacid-enriched specimens. The median reduction in factors VIII:C, VIIIR:Ag, VIIIR:RCF and fibrinogen during lyophilization of ordinary cryoprecipitate was 26 per cent, 11 per cent, 1 per cent and 8.5 per cent, respectively. Heat treatment of such cryoprecipitate resulted in 85 to 98.5 per cent reduction in these parameters, while the reduction following lyophilization and heat treatment (24 hours) of aminoacid-containing preparations was not significantly different from non-heated, ordinary cryoprecipitate. Following heating of aminoacid-enriched cryoprecipitate for 72 hours, only factor VIIIR:RCF was significantly reduced (32.5 per cent) compared to non-heated samples. Ordinary cryoprecipitate was almost insoluble following heat treatment. Enrichment with aminoacids, however, made the heat treated cryoprecipitate fully soluble, but the content of these vials were slightly slower in dissolving than non-heated preparations. Ultracentrifugation prior to lyophilization and heating did not improve the solubility. If heat treatment proves to be efficient in inactivating viral agents, we conclude that heated (68 degrees C for 24 hours), aminoacid-enriched cryoprecipitate may be a convenient product for treating haemophilia A, von Willebrand's disease and hypofibrinogenemia.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Thrombin generation during collection of blood from donors taking oral contraceptives.

Thrombin generation, as evidenced by plasma fibrinopeptide A (FPA) concentrations, was studied during blood collection from donors taking oral contraceptives (OC). 450 ml blood were drawn into Fenwal PVC bags from 26 OC users and 28 nonusers. Blood samples for determination of FPA, beta-thromboglobulin (BTG), thrombotest (TT), prekallikrein (PKK), antithrombin-III (AT-III) and factor VIII procoagulant activity (FVIII:C) were drawn from the bags immediately after ending blood donation and following storage for 24 h at 4 degrees C. The FPA concentrations following donation were significantly higher in the OC than in the control group (p less than 0.05). The levels of PKK were also higher in blood obtained from OC users (p less than 0.001), as was the FVIII:C level, the latter difference, however, was not significant (p = 0.06). No cold-promoted activation of factor VII, as evidenced from TT, was detected following storage at 4 degrees C, neither was any change observed in the FPA, PKK and AT-III levels. The BTG concentrations increased significantly during storage, most pronounced in the control group (p less than 0.05). The decay of FVIII:C was similar in the two groups, averaging 24.7%. No correlation was observed between the FPA levels and the other parameters determined. We conclude that thrombin generation is more pronounced during routine blood collection from donors taking OC.

Adult↗
PubMed1987

Monoclonal IgM with lupus anticoagulant activity in a case of Waldenström's macroglobulinaemia.

Strong lupus anticoagulant activity was detected in the plasma of a 73-yr-old woman with Waldenström's macroglobulinaemia. Purified patient IgM caused significant prolongation of the APTT in concentrations as low as 30 micrograms/ml, and its activity was inhibited by intact or (more effectively) by frozen-thawed blood platelets. Employing varying concentrations of cephalin in the APTT assay, it was demonstrated that the macroglobulin had a direct cephalin-neutralizing effect. When tested in an ELISA system using phospholipid-coated microtiter wells, the IgM was shown to possess antibody activity against cephalin. With purified phospholipids as antigens, the protein was found to display antibody activity against phosphatidyl serine and phosphatidyl ethanolamine, which are main constituents of cephalin. These observations were confirmed in absorption experiments.

Aged↗