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M Spannagl

Publications and source records attributed to M Spannagl.

At least 91 records · Page 5Linked to original sources
PubMed1991

A purified antithrombin III--heparin complex as a potent inhibitor of thrombin in porcine endotoxin shock.

Inhibition of activated clotting factors is an important therapeutic approach in disseminated intravascular coagulation (DIC). We examined the possible protective effect of a purified complex of human antithrombin III (AT III) and heparin in endotoxin-induced DIC in pigs. Two groups of endotoxemic pigs were studied. AT III-heparin group pigs (n = 8) were pretreated with a bolus injection of 500 units AT III-heparin complex, followed by a continuous infusion of 1000 units of the complex for 6 hours given simultaneously with the infusion of 10 micrograms/kgh of S. abortus equi endotoxin. Controls (n = 9) were given saline in addition to the continuous infusion of endotoxin. AT III activity, prothrombin and soluble fibrin in plasma were determined by chromogenic substrate methods. Fibrinogen was measured turbidimetrically. Human AT III antigen in the treated group was 64 +/- 3% at 2 hours and increased to 84 +/- 4% until the end of the experiment. AT III activity in the AT III-heparin group was elevated throughout the whole observation period (greater than 100%), whereas it was significantly lower in the controls. Prothrombin decreased similarly in both groups by approximately 35% until the end of the experiment. AT III-heparin treatment significantly attenuated the endotoxin-induced consumption of fibrinogen and completely prevented the increase in soluble fibrin in plasma. However, no significant effect of AT III-heparin was observed on endotoxin-induced mortality and dysfunction in pulmonary gas exchange. Therefore we conclude that the purified AT III-heparin complex inhibits thrombin effects and prevents development of DIC, but fails to significantly influence clinical outcome in endotoxin shock of the pig.

Animals↗
PubMed1991

Development of a chromogenic substrate assay for the determination of hirudin in plasma.

Hirudin is a potent and specific thrombin inhibitor. Since recombinant hirudin is being considered for anticoagulant and antithrombotic therapy we developed a fast and sensitive chromogenic substrate assay for its determination in plasma. The plasma samples (20 microliters) were incubated with 1 ml reagent mixture (0.2 M Tris buffer, 0.025 M NaCl, pH 8.1, containing 0.833 M urea, 0.7 trypsin inhibitor U/ml aprotinin, 100 ng/ml Polybrene and 0.31 NIH U/ml bovine thrombin) for 1 min. Thereafter 100 microliters Chromozym TH (Tos-Gly-Pro-Arg-pNA, 1.9 mM) was added. The change in absorbance/min (delta A/min) was recorded at 405 nm. delta A/min was linear for at least 3 min. The calibration curve was linear at least up to 800 ng hirudin/ml plasma. Intra-assay and inter-assay coefficients of variation were 2.8-3.1% and 5.3-5.8% respectively. The influence of progressive thrombin inhibitors can be neglected because of the short incubation time. Plasma samples can be assayed directly if aprotinin, polybrene and urea are added to the reagent mixture.

Calibration↗
PubMed1991

Plasmatic factors of haemostasis remain essentially unchanged except for PAI activity during n-3 fatty acid intake in type I diabetes mellitus.

Diabetic patients are prone to develop vascular complications. Increased procoagulatory factors and a reduced fibrinolytic potential are considered as thrombogenic risk factors, although controversy remains. In epidemiological and dietary intervention studies fish or fish oil, rich in the two n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have demonstrated a potential to reduce cardiovascular disease. We compared the plasmatic coagulatory and fibrinolytic profile of 13 near normoglycaemic type I diabetics almost free of cardiovascular disease with healthy volunteers, matched for age and sex. Except for fibrinogen levels and tPA activity being elevated and soluble fibrin and fibrinopeptide A being reduced, no differences could be discerned between type I diabetics and controls in all investigated plasmatic parameters. In a dietary intervention study we investigated the effects of 5.4 g EPA and 2.7 g DHA per day during and after a 4-week dietary supplementation in the diabetic patients. The factors, inhibitors and activation products of coagulation and fibrinolysis measured were at best transiently affected by the diet. Only plasminogen activator inhibitory activity in plasma significantly increased during the dietary supplementation and returned to prediet values after cessation of n-3 fatty acids. Changes in PAI activity were negatively correlated to changes in serum triglycerides. We conclude that well adjusted type I diabetics show an almost unchanged haemostatic profile compared to matched healthy controls. A dietary intervention with n-3 fatty acids in these patients does not affect the plasmatic haemostatic pattern except for an increase in PAI activity.

Adult↗
PubMed1991

Time dependent release of tissue-type plasminogen activator and plasminogen activator inhibitor into the circulation of pigs during shock.

To investigate short-term activation and inhibition of fibrinolysis during shock, we studied plasma levels of tissue-type plasminogen activator (t-PA) and t-PA inhibition capacity (PAI) in anaesthetized pigs. t-PA in euglobulin fractions of plasma was measured by the conversion of plasminogen to plasmin in the presence of fibrin split products. Plasmin thus generated was measured in a chromogenic substrate assay. PAI was measured as plasma inhibition capacity for human melanoma t-PA. Controls (n = 8) had constant t-PA and PAI for 6 h. Lipopolysaccharide from Salmonella abortus equi in four different doses (n = 9 - 11), or live Escherichia coli (n = 3) induced a transient t-PA increase with peak values at 2 h. PAI decreased to 50% at 2 h and increased to 250% at 6 h. Phorbol myristate acetate (n = 7) induced no change of t-PA or PAI. Dextran sulphate (n = 4) produced a t-PA rise at 30 min, followed by a rapid decline. Endotoxin was an appropriate stimulus for activation and inhibition of fibrinolysis whereas phorbol ester failed to elicit this response.

Animals↗
PubMed1991

A triazolodiazepine platelet activating factor receptor antagonist (WEB 2086) reduces pulmonary dysfunction during endotoxin shock in swine.

We wanted to determine the effects of WEB 2086, a platelet activating factor (PAF) antagonist, in lipopolysaccharide (LPS) shock in anesthetized pigs. In a randomized study, LPS from S. abortus equi, 2 micrograms/kg/h was given IV for six hours. Thirteen animals received LPS and WEB 2086, 10 mg/kg/h IV for 6.5 hours, beginning 30 minutes before LPS. Eleven septic controls received saline and LPS, three nonseptic controls received saline and WEB 2086, and three nonseptic controls received saline only. In six animals we investigated the effect of synthetic PAF in doses between 50 and 10,000 ng on arterial (AP) and pulmonary arterial (PAP) pressure before and during infusion of WEB 2086. The LPS-induced rise in PAP was reduced by WEB 2086 (p = 0.01) but not the decrease in AP. The LPS-induced leukopenia, hypoxia, increase in airway pressure, and release of plasminogen activator inhibitor were reduced by WEB 2086. Platelet activating factor produced an increase in PAP and a biphasic response in AP. All PAF dose response curves were shifted to the right by WEB 2086. Platelet activating factor was a pulmonary hypertensive agent and contributed to the LPS-induced respiratory alterations.

Animals↗
PubMed1991

A fast photometric assay for the determination of hirudin.

Recombinant hirudin, a potent and specific thrombin inhibitor, is considered for anticoagulant therapy. Therefore we developed a fast and sensitive chromogenic assay for its determination in plasma. Samples can be assayed directly if aprotinin, Polybrene and urea are added to the reagent mixture. The influence of progressive inhibitors is excluded by a short incubation time. The samples (20 microliters) are diluted with 1 ml reagent mixture (0.2 M Tris, 0.025 M NaCl, pH 8.1, containing 0.833 M urea, 0.7 trypsin inhibitory units/ml aprotinin, 100 ng/ml Polybrene and 0.31 NIH units/ml bovine thrombin). After an incubation time of 1 min, 100 microliters Chromoyzm TH (Tos-Gly-Pro-Arg-pNA, 1.9 mM) is added. delta absorbance/min is linear at least up to 3 min. The calibration curve is linear up to at least 800 ng hirudin/ml plasma. The inter- and intraassay coefficient of variation in hirudin spiked normal plasma is below 5%. The detection limit is at 25 ng hirudin/ml. In plasma samples obtained from healthy subjects under hirudin therapy, a good correlation was found to the activated partial thromboplastin time (r = 0.89). In conclusion, we describe a fast and simple chromogenic substrate test to assay hirudin in plasma. Under assay conditions, the influence of endogenous thrombin inhibitors can be neglected.

Amino Acid Sequence↗
PubMed1991

[Thrombocyte aggregation and fibrinolysis in healthy probands treated with molsidomine, isosorbide-5-mononitrate and placebo].

Twelve healthy volunteers received either a single oral dose of molsidomine (4 mg), isosorbide-5-mononitrate (ISMN, 20 mg), or placebo in a randomized, double-blind fashion. Blood was drawn prior to, as well as 30 and 60 min after intake of the respective drug. Platelet aggregation and the plasma levels/activity of plasminogen activator (tPA) and its inhibitor (PAI-1) were determined. In contrast to ISMN and placebo, molsidomine provoked a significant reduction in platelet aggregability. No alteration in plasma tPA concentrations was observed independent of whether molsidomine, ISMN, or placebo was applied. However, plasma PAI-1 activity was considerably reduced following molsidomine, but not altered following ISMN or placebo. We conclude that a single oral dose of molsidomine, but not of ISMN inhibits platelet aggregation and increases the fibrinolytic potential in healthy volunteers.

Adult↗
PubMed1991

[Local low dosage thrombolysis with rt-PA. Systemic effects on the fibrinolytic system--data on the assessment of the value and risk of this method].

We investigated 70 patients suffering from peripheral vascular disease for alterations in fibrinolytic parameters before, during and twice after local, low dose thrombolysis with rt-PA (1 - 7.5 mg). Recanalization was achieved in all 10 embolic occlusions and in 87% of 60 thrombotic occlusions. We found no alterations of fibrinogen and plasminogen plasma levels, but significant consumption of antiplasmin 5 min after the end of rt-PA application. Degradation products of fibrinogen and fibrin showed a parallel increase only during the therapy. PAI I concentrations significantly increased until the 2nd day after the therapy. Since we limited the maximum dose of rt-PA to 7.5 mg we never saw systemic bleeding or embolisation in more than 300 cases.

Aged↗
PubMed1991

The influence of preoperative anticoagulation on heparin response during cardiopulmonary bypass.

The effect of preoperative anticoagulant therapy on intraoperative heparin response in patients undergoing cardiac operations was examined in a prospective study. The study included 45 patients with different preoperative anticoagulant treatments: 10 patients received treatment with phenprocoumon (a warfarin analogue) (group M), 12 patients received treatment with intravenous heparin (group Hiv), and 13 patients received treatment with subcutaneous heparin (group Hsc). The control group consisted of 10 patients who did not receive anticoagulant therapy before operation (group C). Preoperative antithrombin III activity was highest in group M (85% +/- 6%) and lowest in group Hiv (70% +/- 15%, p less than 0.05). The activated clotting time, determined 10 minutes after bolus injection of 250 IU (group M) or 375 IU heparin (all other groups), was 529 +/- 109 seconds in group C, greater than 1000 seconds in group M, 483 +/- 99 seconds in group Hsc, and 406 +/- 63 seconds in group Hiv (p less than 0.05). Heparin consumption during cardiopulmonary bypass varied between 4.6 +/- 1.4 IU/kg.min (group Hiv) and 2.6 +/- 0.9 IU/kg.min (group M) (p less than 0.05). Despite this increased heparin consumption, the patients who had received heparin before operation demonstrated increased activation of coagulation at the end of cardiopulmonary bypass (thrombin-antithrombin III complex, 19 +/- 4.1 ng/ml in group M and 61 +/- 7 ng/ml in group Hsc, p less than 0.05; cross-linked fibrin fragments, 257 +/- 92 ng/ml in group M and 875 +/- 152 ng/ml in group Hiv, p less than 0.05). Increased platelet activation was also found in patients with preoperative heparin therapy (beta-thromboglobulin at the end of cardiopulmonary bypass was 585 +/- 88 ng/ml in group M versus 1341 +/- 190 ng/ml in group Hsc, p less than 0.05). Drainage from the chest tube 24 hours after operation was 815 +/- 305 ml in group C, 644 +/- 238 ml in group M, 1133 +/- 503 ml in group Hsc, and 950 +/- 505 ml in group Hiv (p less than 0.05 for group M versus group Hsc). This study suggests that patients who receive heparin therapy before operation face a high risk of insufficient anticoagulation during cardiopulmonary bypass if standard heparin doses are used. Therefore, for patients who receive preoperative heparin therapy, a larger (500 IU/kg) initial bolus of heparin is recommended before cardiopulmonary bypass. On the other hand, patients who undergo preoperative treatment with phenprocoumon receive sufficient anticoagulative effect with a heparin bolus of 250 IU/kg.(ABSTRACT TRUNCATED AT 400 WORDS)

Antithrombin III↗
PubMed1990

Hemodialysis, membrane-related neutrophil dysfunctions, and pentoxifylline--a pilot study.

Hemodialysis treatment is associated with activation of neutrophil granulocytes. Pentoxifylline has been shown to inhibit neutrophil activation in vitro and in vivo. We investigated the effect of pentoxifylline on leukocyte and platelet counts and on plasma levels of extracellularly released neutrophil elastase and lactoferrin during a four-hour hemodialysis treatment. Eight patients received 400 mg of pentoxifylline or placebo orally twice a day over 14 days and an additional dose of 400 mg of pentoxifylline intravenously during hemodialysis. Each subject served as his own control in a randomized, double-blind, cross-over study. Combined oral and intravenous treatment with pentoxifylline prevented neither leukopenia nor neutrophil degranulation during the time interval studied. Elastase plasma levels paralleled the drop in leucocyte counts and thereafter increased similarly in both groups. Lactoferrin plasma levels exhibited less increase in the treated group; however, this effect was not statistically significant. This may be due to the small number of cases studied and to difficulties in reaching effective plasma levels without side effects.

Double-Blind Method↗
PubMed1990

Influence of high-dose aprotinin treatment on blood loss and coagulation patterns in patients undergoing myocardial revascularization.

Intraoperative administration of the proteinase inhibitor aprotinin causes reduction in blood loss and homologous blood requirement in patients undergoing cardiac surgery. To ascertain the blood-saving effect of aprotinin and to obtain further information about the mode of action, 40 patients undergoing primary myocardial revascularization were randomly assigned to receive either aprotinin or placebo treatment. Aprotinin was given as a bolus of 2 x 10(6) kallikrein inactivator units (KIU) before surgery followed by a continuous infusion of 5 x 10(5) KIU/h during surgery. Additionally, 2 x 10(6) KIU were added to the pump prime. Strict criteria were used to obtain a homogeneous patient selection. Total blood loss was reduced from 1,431 +/- 760 ml in the control group to 738 +/- 411 ml in the aprotinin group (P less than 0.05) and the homologous blood requirement from 838 +/- 963 ml to 163 +/- 308 ml (P less than 0.05). In the control group, 2.3 +/- 2.2 U of homologous blood or blood products were given, and in the aprotinin group, 0.63 +/- 0.96 U were given (P less than 0.05). Twenty-five percent of patients in the control group and 63% in the aprotinin group did not receive banked blood or homologous blood products. The activated clotting time as an indicator of inhibition of the contact phase of coagulation was significantly increased before heparinization in the aprotinin group (141 +/- 13 s vs. 122 +/- 25 s) and remained significantly increased until heparin was neutralized after cardiopulmonary bypass (CPB).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Effect of recombinant hirudin, a specific inhibitor of thrombin, on endotoxin-induced intravascular coagulation and acute lung injury in pigs.

We hypothesized that thrombin activation may play a prominent role in endotoxin-induced secondary organ failure, such as acute lung injury. To test this hypothesis, we administered a thrombin-specific inhibitor, recombinant hirudin, in endotoxemic pigs. The pigs were anesthetized, mechanically ventilated, and prepared with Swan-Ganz and extravascular lung water (EVLW) catheters. A total of 18 randomly selected animals received a pretreatment of 1,000 U/kg of hirudin, followed by a continuous infusion over 6 h of 500 U/kg/h given simultaneously with the infusion of 10 micrograms/kg/h of Salmonella abortus equi endotoxin. Another 18 animals received a continuous infusion over 6 h of endotoxin but did not receive hirudin. All animals were fluid resuscitated with 17 ml/kg/h of saline for the duration of the experiment. Data are expressed as the mean (95% confidence interval). Hirudin reduced the endotoxin-induced consumption of plasma fibrinogen from -110 (-138 to -82) mg/100 ml to -39 (-67 to -12) mg/100 ml (p = 0.0001) and endotoxin-induced increases in the soluble fibrin in plasma from 434 (369 to 499) ng/ml to 236 (171 to 300) ng/ml (p = 0.0002). These data suggest an effective inhibition of the endotoxin-generated thrombin by hirudin. Furthermore, hirudin significantly reduced endotoxin-induced increases in pulmonary vascular resistance from 32 (27 to 37) kdyn x s x cm-5 x kg to 20 (15 to 25) kdyn x s x cm-5 x kg (p = 0.0015) and increases in EVLW from 15.4 (13.2 to 17.6) ml/kg to 12.2 (10.0 to 14.4) ml/kg (p = 0.0299).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1990

[Is there a favorable time for the management of femoral shaft fractures in polytrauma?].

Despite the wide-spread opinion, that early stabilisation of femur fractures in multiply injured patients is of advantage, there are no publications that unambiguously prove this statement. In contrast, primary fracture stabilisation of the femur with concomitant thoracic trauma seems to increase the rate of complications. The biochemical data of the prospective study presented here suggest, that operative stabilisation of femoral fractures imposes an additional trauma on the already compromised organism. The period between days 2 to 4, when the primary activation of humoral and cellular mediators has returned to normal levels, seems to be the best time for osteosyntheses of these fractures. The operation in this period allows intramedullary fixation--the biologically and biomechanically best fixation procedure--with low risk.

Acute-Phase Proteins↗
PubMed1989

A new AT III-heparin-complex preparation: in vitro and in vivo characterisation.

The in vitro experiments show that the anticoagulant affect of a new AT III-Heparin-complex preparation in plasma is similar to heparin. The in vivo experiments indicate that the thrombin inhibition is even improved by using the complex preparation, because the aPTT values after complex treatment remained stable for more than one hour in the desired range. Bleeding complications are less likely after complex treatment, because much smaller maximum aPTT values are reached. The prolonged half life of the complex preparation possibly allows a reduced and more accurate dosage.

Animals↗
PubMed1989

[Pathogenesis and laboratory diagnosis of venous thrombosis].

UNLABELLED: Due to the increasing number of elderly as well as chronically-ill patients, venous thrombosis assumes an increasing role as a typical complication of many courses of disease. Postoperatively, in patients without anticoagulation, fibrinogen tests show venous thrombosis in the lower extremities in up to 50% but not all were clinically relevant. Prophylactic treatment has markedly lowered the manifestation of deep venous thrombosis. Nevertheless, in current epidemiologic studies, the prevalence of thrombotic disease is three-fold higher (1:7,500) than that of bleeding diseases (1:20,000). PATHOGENESIS: Congenital deficiency or congenital dysfunction of inhibitors of activated clotting factors have provided insight into the functional principles of limited proteolysis. Unequivocal causes of recurrent thrombosis are deficiency or dysfunction of AT III, protein C, protein S or plasminogen (Figure 1). Dysfibrinogenemia, in about 10% of the patients, leads to a tendency to thrombosis. Unclarified remains the relevance of lowered values for factor XII, heparin-cofactor II (HC II) and histidine-rich glycoprotein (HRG) (Table 1). Congenital disorders usually manifest themselves in the early adulthood. For the clinical manifestation of venous thrombosis, imbalance between pro-coagulatory and inhibitor factors are of importance, therefore the compensatory capabilities of other protease inhibitors, for example, alpha-2-macroglobulin should be taken into consideration. In acquired lowering of hemostasis factors, the balance in the plasma protein cascade should be assessed (Figure 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Tests↗
PubMed1989

Therapeutic effects of the combination of two proteinase inhibitors in endotoxin shock of the pig.

Thrombin activation is an important underlying pathomechanism for septic organ failure. The selective thrombin inhibitor, hirudin, reduces the endotoxin-induced fibrinogen consumption and thus the formation of fibrin monomer, as well as the pulmonary vasoconstriction in pigs at plasma concentrations of 70 to 100 nmol/l. PMN cell activation with subsequent release of digestive proteases is in part responsible for the loss of fluid and protein from the vascular compartment during septic shock. Administration of the inhibitor of PMN elastase, cathepsin G and mast cell chymase, eglin C, reduces the loss of intravascular protein during the first 4 hours of endotoxin shock at plasma concentrations in the range of 2 mumol/l.

Animals↗