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Biomedical subjects

H C Godal

Publications and source records attributed to H C Godal.

At least 55 records · Page 3Linked to original sources
PubMed1986

Thrombin generation during collection and storage of blood.

Thrombin generation, as evidenced by radioimmunologic fibrinopeptide A (FPA) determination, was studied upon drawing and storage of blood. Blood from 5 healthy subjects was drawn into Fenwal bags (PL 146, 16-gauge needle, 92-cm collecting tube), and blood samples for FPA analysis were taken from the proximal and distal part of the collecting tubes. The FPA concentrations were considerably higher in the distal part of the tubes both at zero time and after 5 and 10 min, implying substantial thrombin generation to have occurred upon blood passing through the tubes. In 20 healthy blood donors (age 19-52 years) subjected to a standard collection procedure (Fenwal bags PL 146, CPDA formula-1 anticoagulant solution, 450 ml blood), higher FPA values were observed in the bags immediately upon collection, as compared to control venipuncture values (p less than 0.02). Furthermore, in 6 women using oral contraceptives, even larger increases were observed, indicating thrombin generation to be more pronounced in such donors (p less than 0.01). No statistically significant increase in FPA concentrations was found upon storage of CPDA-blood at 4 degrees C for 24 h. There was no correlation between FPA and beta-thromboglobulin (BTG) concentrations after blood collection, indicating alpha-granule release from platelets to be non-thrombin-mediated.

Blood Donors↗
PubMed1985

The molecular localization of the ability of certain monoclonal immunoglobulins to interfere with fibrin polymerization.

When a purified myeloma protein with the ability to inhibit fibrin polymerization was preincubated with sheep anti-human F(ab')2 antibodies, there was a marked reduction of the ability to prolong the thrombin clotting time, while anti-Fc antibodies had only a slight effect. A monoclonal immunoglobulin which shortens the thrombin time was uninfluenced by anti-F (ab')2 as well as by anti-Fc antibodies. Partial reduction and alkylation of the immunoglobulins did not modify their effect on the thrombin time. None of the immunoglobulins bound to fibrinogen or fibrin monomer that had been linked to CNBr-activated agarose. Myeloma proteins may interfere with fibrin polymerization in two ways: some proteins inhibit polymerization in a reaction that depends on the Fab (antigen binding) part of the molecule; however, antibody binding activity against fibrinogen or fibrin monomer has not been demonstrated. Other (rare) myeloma proteins accelerate fibrin polymerization; this effect cannot be ascribed to any particular portion of the molecule and is probably of an unspecific nature.

Animals↗
PubMed1985

Polymerization properties of two normally circulating fibrinogens, HMW and LMW. Evidence that the COOH-terminal end of the a-chain is of importance for fibrin polymerization.

The plasma fibrinogen fractions HMW (mw 340,000) and LMW (mw 305,000) were prepared from purified (beta-alanine precipitated) fibrinogen by step-wise precipitation with ammonium sulfate. The thrombin clotting times were 14" and 20" respectively. The enzymatic phase of coagulation, measured as release of fibrinopeptide-A during incubation with thrombin, was found to be identical for HMW and LMW. Polymerization was studied by light scattering (at 605 nm) using preformed monomers (des-AA and des-AABB) prepared from HMW and LMW in the presence of 3.3 M urea by incubation with thrombin (100 NIH U/ml final conc.) and reptilase (1 U/ml final conc.). The HMW-monomers polymerised at a substantially higher rate than the corresponding LMW-monomers. Thus, the prolonged clotting time of LMW was explained by retarded polymerization. It is suggested that the -COOH terminal end of the a-chain, containing the molecular difference between HMW and LMW, is of importance for polymerization. Furthermore, the release of fibrinopeptide B (des-AABB-monomers) improved polymerization properties in HMW as well as in LMW, and all types of monomers polymerised more rapidly in the presence of Ca++.

Fibrin↗
PubMed1985

Evidence that changes in fibrinogen quality during acute phase reactions are of major importance for the amount of heparin precipitable fraction (HPF).

The influence of qualitative and quantitative changes in plasma fibrinogen upon the amount of heparin precipitable fraction (HPF), obtained during the course of acute disease states, were examined. Whereas fibrinogen in plasma includes 3 species of different molecular weights (HMW, LMW, LMW'), fibrinogen in HPF, from normal as well as from "acute phase" plasma, consisted almost exclusively of HMW-fibrinogen (3% SDS-PAGE). Sub-unit chain electrophoresis (10% PAGE-SDS and two-dimensional electrophoresis) did not disclose any signs of abnormalities in the fibrinogen precipitated in HPF. Studies on patients revealed that the composition of plasma fibrinogen changed (increased HMW) during the course of acute myocardial infarction and following hip operations, and indicated that the amount of HPF was governed by the relative amount of HMW-fibrinogen as well total fibrinogen. This assumption was strengthened by quantitating the amount of HPF obtained after addition of highly purified HMW and LMW fibrinogen to normal and "acute phase" plasma. It is concluded that fibrinogen quality (per cent HMW or HMW/LMW ratio) is of major importance for the amount of HPF, thereby explaining some of the HPF-variations seen during the course of acute diseases.

Acute Disease↗
PubMed1985

Purification and characterization of 3 fibrinogens with different molecular weights obtained from normal human plasma.

Fibrinogen was purified from fresh citrated human plasma by precipitation with beta-alanine in the presence of citrate and protease inhibitors. From this material, fractions corresponding to the HMW (high molecular weight), LMW and LMW' fibrinogen fractions of plasma were obtained by step-wise precipitation with ammonium sulfate. Electrophoresis revealed that HMW was contaminated with 4% LMW, LMW was contaminated with 6% HMW, and the LMW'-fraction was a mixture of LMW' (50%), LMW (20%) and two derivatives of intermediate m.w.. The HMW fraction (mw. 340 000) contained intact Aa-chains, while the molecular weight of LMW was reduced to 305 000 and that of LMW' to 270 000 due to proteolysis of the -COOH terminal end of one (LMW) or both (LMW') Aa-chains. The clottability of HMW was 98%, of LMW 92% and of LMW' about 80%. Thrombin clotting times (1 NIH U/ml) were 14", 20" and 25" resp. These differences were highly accentuated when clotting was performed with reptilase (14", 38" and 120"). Contamination with soluble fibrin was less than 2% and the contents of fibronectin and AT-III were low. No thrombin or plasmin activity was generated upon 24 hours incubation at +4 degrees C as evidenced by increased content of fibrinopeptide-A and fragment Bb-15-42 resp.

Electrophoresis, Polyacrylamide Gel↗
PubMed1985

Effect of high-dose ampicillin and cloxacillin on bleeding time and bleeding in open-heart surgery.

To determine if platelet dysfunction caused by high doses of penicillin compounds is of practical importance in patients with additional haemostatic defects perioperatively, a study was made of patients undergoing open-heart surgery. They were randomly assigned to prophylactic treatment with ampicillin 8 g plus cloxacillin 4 g daily for three days, or with cephalothin 8 g daily for three days. Fifty patients in each group were evaluated. The median bleeding time preoperatively and on days 1 and 4 postoperatively did not differ between the groups. The bleeding time was prolonged beyond the normal range in eight patients of the ampicillin/cloxacillin group and in three of the cephalothin group (p less than 0.05). Prolonged bleeding time was not associated with lower platelet count or greater blood loss. The total blood loss and the amounts of transfused blood, platelets and cryoprecipitate were all greater in the ampicillin/cloxacillin group, but the difference was not statistically significant. Combined use of ampicillin and cloxacillin in open-heart surgery is associated with increased bleeding, but the increase is without practical importance.

Adolescent↗
PubMed1985

No discriminating power in FPA measurements during fibrinaemia in hip replaced patients generating DVT.

Fibrinaemia following total hip replacement was evaluated in eighteen patients, grouped according to a negative and a positive fibrinogen uptake test (FUT), after having excluded two patients due to a false negative test, using phlebography as reference. The ethanol gelation test (EGT) was employed for detection of circulating soluble fibrin, and the conversion of fibrinogen to fibrin was evaluated by the level of fibrinopeptide A (FPA). Eight patients were cleared with respect to thrombosis, whereas ten had a positive FUT. All patients developed a positive EGT, irrespective of thrombosis, coinciding with the postoperative increase in fibrinogen. FPA increased to approximately twice its preoperative level in both groups of patients, but reached its maximum earlier in patients with thrombosis. However, this parameter had no discriminative value in this type of postoperative thrombosis, possibly due to massive thromboplastin release in both groups.

Aged↗
PubMed1985

Clearance characteristics of des-AA fibrin and des-AABB fibrin, and thrombus-related uptake of des-AABB fibrin as compared to fibrinogen.

The following paper presents a short review of previous studies relating to the behaviour in man of radiolabelled fibrins des-AA and des-AABB, as compared to that of radiolabelled fibrinogen. Des-AA fibrin was eliminated with a half-life of 30 to 60 min in eight healthy controls, but its half-life was substantially shorter in eight fibrinaemic patients with no demonstrable fibrinolysis. Clearance of des-AABB fibrin was studied in thirteen patients with established venous thrombosis, all subjected to a concomitant fibrin(ogen) uptake test. There was no essential difference in its half-life in patients with a positive fibrinogen uptake test (n = 7) as compared to those with a negative test (n = 6). The metabolic half-life of des-AABB fibrin was 10 +/- 3.5 hrs. The uptake of labelled des-AABB fibrin by thrombi was similar to that of labelled fibrinogen during the first hours after injection, but only fibrinogen could reflect a continuous build-up of thrombi, due to its longer survival time.

Fibrin↗
PubMed1985

Plasmapheresis in the treatment of severe meningococcal or pneumococcal septicaemia with DIC and fibrinolysis. Preliminary data on eight patients.

Plasmapheresis (50 ml fresh frozen plasma/kg body weight per session--total 9-11 liters) was performed within 36 hours of the onset of septicaemia in 7 patients (1 woman and 6 men, age 14-48 years). One 8 year old girl was treated with exchange blood transfusion (2 liters). All had symptoms of severe septic shock caused by Neisseria meningitidis (6) or by Streptococcus pneumoniae (2). All patients demonstrated signs of DIC and concomitant fibrinolysis with low platelet values, normal to low fibrinogen levels, circulating soluble fibrin and increasing amounts of FDP. Persistent extreme values were observed in 2 patients that died, whereas coagulation/fibrinolysis parameters frequently improved during plasmapheresis and gradually (more than 6 days) returned to normal values in the survivors. Although plasmapheresis was largely successful and signs of DIC and fibrinolysis were normalized, 2 patients died and 1 survived with severe sequelae. Thus, it remains to accumulate more data to conclude if plasmapheresis is beneficial in the treatment of severe septic shock and DIC.

Adolescent↗
PubMed1984

Venous thrombosis following diagnostic transvenous catheterization by percutaneous catheter insertion: an evaluation of desmopressin as a thromboprophylactic agent.

The preventive effect of desmopressin with respect to catheter induced thrombosis was studied in a randomized double-blind trial, consisting of 30 patients undergoing percutaneous transcubital right heart catheterization. Phlebography of the catheterized arm was performed after five days. The frequency of post-catheterization thrombosis was reduced by 33 per cent, from 86 per cent in the treatment group to 53 per cent in the control group (0.1 less than p less than 0.2). This effect was restricted to minor thrombi, whereas major thrombosis could not be prevented. Patient materials such as that of the present study, may become useful in preliminary investigations of thromboprophylactic agents.

Arginine Vasopressin↗
PubMed1984

Quantitation of factor XIII by SDS polyacrylamide gel electrophoresis.

An electrophoretic method for the determination of f.XIII, based on the capability of f.XIIIa to cross-link fibrin clots (5) was studied, and the great sensitivity of the method confirmed. Thus, with suitable technical conditions, f.XIII activities less than 0.1% of that in normal human plasma could be detected. The results obtained in plasma from various patients and in f.XIII concentrates (cryoprecipitates) corresponded well with those obtained with the dansylcadaverine method (3) and with the urea solubility test, with two exceptions: In a patient with severe congenital f.XIII deficiency, only the present method was sensitive enough to detect any f.XIII-activity (about 0.1%), and in a patient with an inhibitor against f.XIIIa, the dansylcadaverine method failed to detect this. The present method is too laborious for routine screening, but is recommended as an alternative references method. It may prove especially suitable to detect minute amounts of f.XIII.

Cadaverine↗
PubMed1984

Quantitation of the three normally-occurring plasma fibrinogens in health and during so-called "acute phase" by SDS electrophoresis of fibrin obtained from EDTA-plasma.

Normal human plasma contains fibrinogens of different molecular weight. To quantitate these fibrinogens, plasma was clotted at pH 6.4 with 7.5 NIH U/ml thrombin in the presence of 8 mM EDTA. The clots were dissolved in 6.6 M urea and submitted to SDS electrophoresis on gels containing 3% polyacrylamide/0.5% agarose, and the fractions quantitated by densitometric scanning. The reproducibility of this method was high with variation coefficient 1.5%. Three main fibrinogen fractions were found: High molecular weight fibrinogen (HMW, mw 340 000), low molecular weight fibrinogen (LMW, mw 300 000) and LMW' (mw 280 000). In addition 5 weak bands could be seen. In plasma from 123 healthy subjects of both sexes, aged 1-93 years, HMW constituted 69.7% +/- 5.1, LMW 26.5% +/- 4.8 and LMW' 3.8% +/- 1.8 of the total fibrinogen. Women and older subjects displayed a small, but statistically significant reduction in the relative amounts of HMW (2-4%). Following surgery and extensive acute myocardial infarction the HMW/LMW ratio changed. The substantial increase in total fibrinogen regularly recorded was mainly due to HMW that reached maximal values after 3-4 days. LMW remained unchanged the first 2 days and then displayed a slight increase with a delayed maximum (8-11 days).

Adolescent↗
PubMed1984

Inhibition or acceleration of fibrin polymerization by monoclonal immunoglobulins and immunoglobulin fragments.

A prolongation of the thrombin clotting time by at least 25% was found in the presence of 8 of 26 IgG myeloma proteins, 2 of 5 IgA proteins and 1 of 10 macroglobulins, in a concentration of 10 mg/ml. Normal pooled immunoglobulin in concentrations up to 83 mg/ml were inactive. 2 IgG and 2 IgM monoclonal immunoglobulins caused an acceleration of the thrombin time by at least 20%; this phenomenon has not been reported before. Corresponding results were obtained with these proteins when the polymerization of des-AA and des-AABB fibrin monomers were investigated in a light scattering system. Studies with enzymatically produced Fab, F(ab')2 and Fc fragments from normal and monoclonal immunoglobulin suggested that the polymerization inhibitory activity resides in the Fab portion of the immunoglobulin molecule. While the ability to inhibit fibrin polymerization may be an immunoglobulin specific effect, the acceleration caused by certain other monoclonal immunoglobulins may be an unspecific effect similar to that seen with dextran or albumin.

Animals↗