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Query: UMLS:C0012739 (
disseminated intravascular coagulation
)
8,673
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
An experimental animal model of
disseminated intravascular coagulation
(
DIC
) induced by the co-infusion of coagulant-active phospholipid and activated Factor X (Factor Xa) is described. The infusion of Factor Xa at a dose of 6.6 X 10(-12) mol/kg with phosphatidylcholine/phosphatidylserine (PCPS) lipid vesicles at a dose of 4.0 X 10(-8) mol/kg was associated with significant falls in the levels of fibrinogen and Factors V and VIII, and a bleeding diathesis developed. Assays of Factors V and VIII were performed by a one-stage prothrombin time and activated partial thrombin time system, respectively. In additional experiments, the effect of the same dose combination of Factor Xa/PCPS on Factor V kinetics was studied by preinfusing 125I-labeled Factor V. After Factor Xa/PCPS infusion, Factors VIII and V were reduced at 2 min by 90 and 50% of the preinfusion levels, respectively, and at 1 h by 80 and 75%, respectively. During the same period, there was little change in the total circulating radioactivity. Autoradiography indicated small but detectable levels of circulating proteolytic products of Factor V that comigrated with peptides obtained by the incubation of Factor V with Factor Xa and
activated protein C
. The majority of radioactivity remained associated with the intact single-chain precursor Factor V. These observations suggested maintenance of the precursor pool after the onset of
DIC
. This was confirmed by performing two-stage assays of Factors V and VIII, whereby each was completely converted to the active cofactor, i.e., Va and VIII:Ca, by preincubation of the test sample with thrombin before assaying in a one-stage system as before. The Factor V levels assayed by the two-stage procedure did not change appreciably over 1 h. The Factor VIII levels fell but corrected within 1 h at a time when the level measured by a one-stage assay remained depressed. These results indicate that in the dog, infusion of Factor Xa/PCPS induces changes characteristic of
DIC
, and this is associated with the appearance of Factor V peptides characteristic of the expression of Factor Xa and
activated protein C
-like activities. The differences noted between the one-stage and two-stage assays suggest that the one-stage assay is measuring the activated fraction of each cofactor and not the total level of the available precursor for each activated species. The results suggest a close correlation between the activated fraction of both cofactors and the hemostatic abnormality that occurs in
DIC
.
...
PMID:Studies of Factors V and VIII:C in an animal model of disseminated intravascular coagulation. 643 44
A relapsing clinical syndrome of skin lesions and
disseminated intravascular coagulation
(
DIC
) that showed remission with the infusion of fresh frozen plasma is described in a newborn infant with homozygous deficiency of
protein C
antigen. This patient presented since birth a recurrent clinical picture of
DIC
and ecchymotic skin lesions that resembled typical ecchymosis except for the fact that they showed immediate improvement with the administration of fresh frozen plasma. Using an enzyme linked immunosorbent assay method, the determination of
protein C
antigen levels in the patient, without ingestion of coumarin drugs, showed very low values (less than 1%). No other deficiencies in the vitamin-K-dependent factors or in antithrombin III, antiplasmin, and plasminogen were found. Seven relatives of the infant had heterozygous deficiency in
protein C
antigen (values between 40-55%), without clinical history of venous thrombosis. The pedigree analysis of this family suggests an autosomal recessive pattern of inheritance for the clinical phenotype, although an autosomal dominant pattern has been postulated until now in other reported families. We conclude that our patient has a homozygous deficiency in
protein C
and this homozygous state may be compatible with survival beyond the neonatal period.
...
PMID:Severe inherited "homozygous" protein C deficiency in a newborn infant. 654 87
We measured levels of protein C inhibitor in patients with
disseminated intravascular coagulation
(DIC) and liver disease using a functional assay. Levels in 24 normal subjects averaged 93% of the amount in normal pooled plasma, giving a normal range of 65 to 121%. Levels were below normal in 8 of 17 patients with DIC, in 4 of 19 patients with liver cirrhosis, and in 3 patients with acute hepatic necrosis. Levels were normal or elevated in 9 of 10 patients with cirrhosis and accelerated fibrinolysis, and in 6 patients receiving warfarin. We conclude that protein C inhibitor may be involved in regulation of
protein C
activity during pathologic activation of the hemostatic system (DIC). Decreased protein C inhibitor does not appear to contribute to the pathogenesis of accelerated fibrinolysis in liver disease. The liver may be the site of synthesis of protein C inhibitor.
...
PMID:Behaviour of protein C inhibitor in intravascular coagulation and liver disease. 654 88
We have developed a radioimmunoassay (RIA) for the dodecapeptide that is liberated from
protein C
when this zymogen is activated by thrombin bound to thrombomodulin present on the vascular endothelium. The
protein C
activation peptide (PCP) was synthesized using the solid-phase method of Merrifield. Antisera were raised in rabbits to the synthetic analogue coupled to bovine serum albumin with glutaraldehyde. The antibody population obtained was used together with a 125I-labeled tyrosinated ligand and various concentrations of unlabeled PCP to construct a double antibody RIA capable of measuring as little as 10 pM of this component. We have established that the synthetic dodecapeptide has the same immunoreactivity as the native peptide and that the reactivity of
protein C
is less than 1/2,000 that of PCP on a molar basis. The extremely low levels of peptide in normal individuals as well as the nonspecific contributions of plasma constituents to the immunoreactive signal, necessitated the development of a procedure by which the PCP could be reproducibly extracted from plasma and concentrated approximately 20-fold. This methodology permitted us to demonstrate that the plasma PCP levels in 17 normal donors averaged 6.47 pM, and that elevations up to 180 pM were observed in individuals with evidence of
disseminated intravascular coagulation
. The validity of these measurements of
protein C
activation is supported by the fact that, in both of these situations, the RIA signal migrates on reverse-phase high pressure liquid chromatography in a manner identical to that of the native dodecapeptide. We have also noted that the mean PCP concentration in seven patients fully anticoagulated with warfarin averaged 2.61 pM. Our studies also show that PCP is cleared from the plasma of primates with a t1/2 of approximately 5 min. Given that the t1/2 of
activated protein C
is estimated to be 10-15 min, the latter enzyme appears to exert its effects on the activated cofactors of the coagulation system at concentrations considerably less than 1.0 nM.
...
PMID:Detection of protein C activation in humans. 654 15
Protein C
, a newly identified inhibitor of blood coagulation, was measured immunologically in 58 patients with untreated acute leukemias and compared with that of normal subjects. On the average, slightly lower values were found. However, the 17 patients with overt laboratory pictures of decompensated
disseminated intravascular coagulation
(
DIC
), including 11 cases with acute promyelocytic leukemia, had
protein C
concentrations no lower than those of the remaining 41 patients without
DIC
. Antithrombin III activity and antigen were normal and, like
protein C
, not lowered in
DIC
. The concentrations of both proteins were closely correlated with changes in the indexes for liver synthetic function. A subgroup of 13 patients with hyperleukocytic leukemias had lower
protein C
and antithrombin III, in line with the more compromised synthetic function of their livers. Our findings indicate that liver impairment rather than
DIC
is the main cause of the changes in the two naturally occurring inhibitors of blood coagulation.
...
PMID:Liver dysfunction rather than intravascular coagulation as the main cause of low protein C and antithrombin III in acute leukemia. 658 88
We describe a functional assay for
protein C
in human plasma samples based on the ability of
activated protein C
to prolong the kaolin-cephalin activated partial thromboplastin time of normal plasma.
Protein C
is separated from its inhibitor by elution of a barium citrate precipitate, and activated by incubation with human alpha-thrombin for one hour. Thrombin is then inhibited by antithrombin III and heparin, heparin neutralized by protamine sulfate, and
protein C
activity measured in the partial thromboplastin time. 24 normal subjects had a mean
protein C
level of 94 +/- 12% (SD) of the activity in pooled normal plasma. Seven patients with severe liver disease had a mean
protein C
of 28%. Eleven patients with
disseminated intravascular coagulation
had a mean
protein C
of 29%. Eight patients receiving warfarin therapy had a mean
protein C
of 17%. The assay is relatively simple and should be suitable for general laboratory use.
...
PMID:A functional assay for protein C in human plasma. 668 83
We examined the anticoagulant activity of two major molecules of soluble thrombomodulin purified from human urine. The apparent molecular weights of these urinary thrombomodulins (UTMs) were 72,000 and 79,000, respectively. Both UTMs showed more potent cofactor activity for
protein C
activation [specific activity > 5,000 thrombomodulin units (TMU)/mg] than human placental thrombomodulin (2,180 TMU/mg) and rabbit lung thrombomodulin (1,980 TMU/mg). The UTMs prolonged thrombin-induced fibrinogen clotting time (> 1 TMU /ml), APTT (> 5 TMU/ml), TT (> 5 TMU/ml) and PT (> 40 TMU/ ml) in a dose-dependent fashion. These effects appeared in the concentration range of soluble thrombomodulins present in human plasma and urine. In the rat
DIC
model induced by thromboplastin, administration of UTMs by infusion (300-3,000 TMU/kg) restored the hematological abnormalities derived from
DIC
in a dose-dependent fashion. These results demonstrate that UTMs exhibit potent anticoagulant and antithrombotic activities, and could play a physiologically important role in microcirculation.
...
PMID:Soluble thrombomodulin purified from human urine exhibits a potent anticoagulant effect in vitro and in vivo. 748 7
Thrombin and plasmin generation were assessed in patients with endemic hepatosplenic schistomiasis (15 hepatosplenomegalic, 15 splenomegalic, 15 with advanced hepatic fibrosis and ascites and 15 hepatosplenic patients with hematemesis). Prolongation of prothrombin time, partial thromboplastin time and thrombin time, thrombocytopenia, hypofibrinogenemia, a decrease in antithrombin III and
protein C
and S levels and elevation in fibrinopeptide A, D-dimer and thrombin-antithrombin complex levels were detected in all groups. The deficit in hemostatic parameters was more pronounced with the advancement of the disease and was maximal in the hematemesis group. Our data demonstrate an increase in both thrombin and plasmin generation and indicate that low grade
disseminated intravascular coagulation
may occur in association with endemic Egyptian hepatosplenic schistosomiasis even in the steady state without overt bleeding.
...
PMID:Disseminated intravascular coagulation in endemic hepatosplenic schistosomiasis. 748 60
Thrombotic events have been reported in acute lymphoblastic leukaemia patients, especially during or after L-asparaginase administration. A so-called L-asparaginase associated coagulopathy has been well recognized, being characterized by a hypercoagulable state (decrease of antithrombin III, plasminogen,
protein C
, protein S and increase of prothrombin fragment F1 + 2, thrombin-antithrombin complexes and fibrinopeptide A). The aim of this study was to determine whether the supplementation of antithrombin III (AT-III) concentrates could improve the L-asparaginase associated coagulopathy, thereby blocking the activation of the haemostatic system. In 25 adult patients with acute lymphoblastic leukaemia (M 19, F6, mean age 34 years) antithrombin III (AT-III) concentrates were administered at daily doses of 50 U/kg for 10 consecutive days from the beginning of L-asparaginase therapy (6,000 U/m2/day s.c. for 7 days), given according to the GIMEMA ALL 0288 trial. A marked increase of antithrombin III was recorded on days IV-VIII-XI (P < 0.001). No changes in
protein C
, protein S, plasminogen, alpha 2-antiplasmin, factor VII and platelet count were observed and there was no increase in markers of hypercoagulability. There was no evidence of
disseminated intravascular coagulation
. In conclusion, AT-III concentrate supplementation during L-asparaginase therapy, by the achievement of high levels of antithrombin III, is associated with a lack of activation of the haemostatic system and appears to overcome the complex coagulopathy associated with L-asparaginase.
...
PMID:Antithrombin III infusion suppresses the hypercoagulable state in adult acute lymphoblastic leukaemia patients treated with a low dose of Escherichia coli L-asparaginase. A GIMEMA study. 751 43
Patients with liver failure can present both thrombotic and hemorrhagic complications because of the deficiency in coagulation factors and inhibitors (
protein C
and S, antithrombin III) and impairment of fibrinolytic balance. Here we report the case of a 63-year-old man with liver cirrhosis, recurrent thrombosis, and features of low-grade
consumption coagulopathy
, showing severe antithrombin III deficiency (about 30% of normal values). Treatment with antithrombin III (2000 U/day) and low doses of heparin (5000 U b.i.d.) was successful in modulating the coagulation system toward an antithrombotic effect. After discharge from hospital the ambulatory treatment with antithrombin III concentrates (2000 U twice a week) allowed the attainment of antithrombin III activity of about 60% and prevented the patient from recurrence of venous thrombosis.
...
PMID:Modulation of hemostatic balance with antithrombin III replacement therapy in a case of liver cirrhosis associated with recurrent venous thrombosis. 762 35
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