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A hitherto undescribed plasma factor acting at the contact phase of blood coagulation (Flaujeac factor): case report and coagulation studies.

This paper reports an asymptomatic coagulation defect responsible for an abnormality at the contact phase of blood coagulation in vitro, distinct from Hageman factor and Fletcher factor deficiencies. Coagulation studies in a 50-yr-old French woman without bleeding tendency revealed the following results: whole-blood clotting time in glass tubes and activated partial thromboplastin time with kaolin and ellagic acid were greatly prolonged; one-stage prothrombin was normal; no circulating anticoagulant was detected, and the infusion of normal plasma corrected the coagulation defect with an estimated half-life of 6.5 days; the levels of factor VIII, IX, XI, and XII were normal; mutual correction was obtained with a Fletcher factor-deficient plasma; the level of whole complement was normal. Studies of the contact phase of blood coagulation and contact-induced fibrinolysis showed the same abnormalities as in Hageman factor- and Fletcher-deficient plasmas. These results indicate that the patient's plasma is deficient in a previously undescribed coagulation factor, which participates in the initial stage of the blood coagulation process in vitro. Family studies revealed consanguinity in the propositus' parents. The assay of this newly described factor in the propositus' children revealed a partial defect, compatible with a heterozygous state, in three of the four tested children. This indicates a recessive inheritance of this new blood coagulation defect.

Blood Coagulation

Coagulation activation is associated with genomic-instability-related features in TP53-mutated AML and MDS: routine laboratory patterns beyond classical disseminated intravascular coagulation.

BACKGROUND: Disseminated intravascular coagulation (DIC) is a serious complication of acute myeloid leukemia (AML) associated with poor prognosis. In TP53-mutated AML and myelodysplastic syndrome (MDS), however, the classical ISTH criteria rarely identify overt DIC, although bleeding and thrombotic complications are well documented in acute leukaemia. We hypothesized that these patients exhibit a lower-grade, subclinical coagulation activation that is associated with the underlying genomic-instability-related features of TP53-mutant disease. METHODS: We retrospectively analyzed 107 consecutive patients with TP53-mutated AML (n = 52) or high-risk MDS (MDS, n = 55), median age 65 years, diagnosed and initially evaluated at our centre between 2018 and 2025. Seven routine coagulation markers and 46 co-mutated genes were evaluated for associations with overall survival (OS) using univariate and multivariable Cox regression, continuous dose-response modeling, and unsupervised k-means clustering. Internal validity was assessed by 1000 bootstrap resamples. RESULTS: Overt DIC according to ISTH criteria was rare (15%). Subclinical activation was common: 50% of patients had a D-dimer &#x2265;1&#xa0;&#x3bc;g/mL, 41% a fibrinogen &#x2265;4&#xa0;g/L, and 29% an INR &#x2265;1.2. In univariate analysis, D-dimer, fibrinogen, INR, prothrombin time, and activated partial thromboplastin time were each associated with OS (HR 1.33-1.38 per SD; all p < 0.05). Complex karyotype correlated with higher D-dimer (median 1.39 vs. 0.60&#xa0;&#x3bc;g/mL, p = 0.022) and fibrinogen (3.91 vs. 2.53&#xa0;g/L, p = 0.007), while TP53 variant allele frequency (VAF) showed modest positive correlations with D-dimer (&#x3c1; = 0.21), INR (&#x3c1; = 0.27), and PT (&#x3c1; = 0.27; all p < 0.05). Clustering identified three coagulation phenotypes: Silent (51%), Thrombo-inflammatory (31%), and Consumption-like (18%), showing a graded but statistically non-significant gradient in molecular features and a stepwise decline in median OS (14, 10 and 8 months; log-rank p = 0.041). After adjustment for complex karyotype, TP53 VAF, and favorable co-mutation count, the Consumption-like phenotype was associated with a non-significant increased risk (HR 1.83, 95% CI 0.92-3.65, p = 0.084), whereas favorable co-mutation pathways remained independently protective (HR 0.56, 95% CI 0.35-0.90, p = 0.016). CONCLUSION: In TP53-mutated AML/MDS, coagulation activation intensity is associated with the degree of genomic instability. The three phenotypes may add biological resolution beyond classical DIC and cytogenetic risk groups, but represent laboratory patterns rather than validated bleeding or thrombosis prediction tools. However, after accounting for genomic features, phenotypes were not independent predictors of outcome, with complex karyotype, TP53 VAF, and favorable co-mutation count driving prognosis. Because treatment intensity and other clinical confounders were not available, these survival associations are hypothesis-generating. Coagulation profiling remains inexpensive, widely accessible, and offers a practical window into disease biology that warrants prospective validation.

TP53

IgE-induced blood coagulation alterations in the rabbit: consumption of coagulation factors XII, XI, and IX in vivo.

Intravenous administration of BSA into 3-month-old rabbits producing detectable anti-BSA antibody only of the IgE class of immunoglobulin induced a variety of intravascular blood coagulation alterations observed in the plasma 15 min after antigen challenge included: a) the intravascular consumption of intrinsic blood coagulation factors XII, XI, and IX and possibly the reduction in clottable fibrinogen; b) a significant prolongation of the activated partial thromboplastin time but not the prothrombin time; and c) the production of an inhibitor affecting the last stage of blood coagulation. The observed blood coagulation alterations were not caused by the manipulative procedures utilized, the presence of anti-BSA, IgG or IgM antibody, histamine-induced alterations in the vascular endothelium or the development of hypotensive shock. It is proposed that specific IgE antibody can induce directly or indirectly the activation of intrinsic blood coagulation in vivo.

Aminocaproates

Kinetics of plasma coagulation and lysis I: Basic kinetic model for time course of coagulation-lysis systems and its potential application to clinical studies.

The time courses of coagulation and coagulation-lysis were spectrophotometrically monitored after the addition of thrombin or thrombin-streptokinase to plasma, diluted 1:5 with normal saline, obtained from normal and presumably abnormal subjects. The kinetics of clotting, after an initial lag period of 0.5-1.5 min, demonstrated essentially first-order dependence on the amount of fibrinogen available to form the clot, and the asymptotic absorbance was independent of thrombin concentration. The rate of clotting was a function of added thrombin, and the ratios of the rate constants at 2.5 and 1.25 units of thrombin/ml of undiluted plasma were 1.65 +/- 0.03 SEM. At early times, the coagulation-lysis curve with thrombin-streptokinase could be superimposed on the clotting curve with thrombin alone for a given plasma with minor compensation for variable lag times. Subsequently, the curves diverged; lysis was monitored by the decrease in absorbance of the coagulation-lysis system. The rate of fibrinolysis increased with streptokinase concentration and was a function of the extent of lysis, and it permitted the description of the kinetics of lysis by a pseudoautocatalytic mechanism where the bimolecular rate constant appears proportional to streptokinase concentration. Ranges of clotting and lytic parameters for the plasma of normal subjects are given, and their potential use in diagnosing abnormalities is described.

Blood Coagulation

Progestational agents and blood coagulation. VIII. Effect of low-dose, alternate-day, estrogen-progestin combinations on blood coagulation factors in man, with a special note on the effect of freezing of blood samples.

Changes in the blood coagulation system were studied in three groups of 20 patients each. The first group received 0.5 mg. of norethindrone daily, plus 0.06 mg. of ethinyl estradiol on alternate days from cycle Day 5 through 25. The second group, all of whom had been fitted with an intrauterine contraceptive device (IUD), received no hormonal treatment and served as a control group. The third group received 0.5 mg. of norethindrone daily, combined with 0.045 mg. of ethinyl estradiol given on alternate days from cycle Day 5 through 25. Blood samples were drawn prior to the initiation of the study and after three months of treatment. Tests of the following parameters of the blood coagulation system were performed: direct platelet count; platelet adhesiveness; prothrombin time; thrombin time; fibrinogen; factor II assay; activity of factors V, VII, VIII, IX, and X; antithrombin III; and fibrin/fibrinogen degradation products. For a number of these factors, both fresh and frozen blood samples were examined. It was concluded that the two treatment regimens, with the use of alternate-day estrogen administration over a three-month period, had no clinically significant effect on the blood coagulation system.

Adolescent

Activation of coagulation and disseminated intravascular coagulation in the newborn.

Human newborns have certain hemostatic "deficiencies" which seem to be peculiar to this period of life, such as reduced factors II, VII, IX, X, XI, and XII, reduced antithrombin III levels, and reduced plasminogen levels. However, they are capable of activating the coagulation mechanism to elicit either the entity of disseminated intravascular coagulation or the occurrence of localized and diffuse thrombotic events. The mechanisms involved have yet to be defined. Evidence has been presented to suggest that preterm infants may manifest a variant form of disseminated intravascular coagulation in which thrombocytopenia is not present.

Adult

Simultaneous determination of coagulation and fibrinolysis parameters for diagnostics of disseminated intravascular blood coagulation (DIC).

A diagnostic method is described for determining the parameters of the human blood plasma coagulation and fibrinolysis by turbidimetry. Diluted plasma with thrombin and streptokinase is mixed to initiate clot formation and subsequent clot dissolution. The resultant profile of absorbance versus time is analysed to determine six parameters: plasma coagulation time, the rate of coagulation, fibrinogen concentration, the rate of fibrinolysis, fibrin clot half-lysis and lysis time. The assay is precise, sensitive and requires 0.1 ml plasma. The method has a good correlation with generally accepted haemostatic tests and allowed us to recognize the stage of DIC syndrome for less than 10 minutes. This new approach was successfully applied for studying the haemostasis in patients with acute intestinal infection.

Blood Coagulation

Fluorogenic detection of primary amines in plant histochemistry with fluorescamine: a comparative study on the effects of coagulant and non-coagulant fixatives.

The new highly sensitive method of fluorescamine reaction for the topochemical detection of primary amino groups was studied as a substitude of ninhydrin-Schiff's reaction for the localisation of total proteins in plant tissues. The influence of various coagulant and non-coagulant fixatives on the induction of fluorescamine fluorescence was examined: ethanol, formaldehyde gas and solution, glutaraldehyde, acrolein, osmium tetroxide, Bouin, Rossman, Clarke and Zenker's fluids and FMA were employed. It was found that the use of the fluorogenic method is conditioned by the fixative ability to keep the amino groups disposable and by its capability to reduce the natural autofluorescence of plant material. A detailed account of the fixation methodology demonstrated that non-coagulant acrolein and coagulant mercuric chloride are the most promising fixatives for the use of the fluorescamine reaction in plant histochemistry.

Amines

[Coagulation disorders due to burns. Disseminated intravascular coagulation (DIC) and its possible prevention].

Coagulation data were studied in 77 patients with severe burns divided into two groups (A, 45 cases, and B, 32 cases). Increased PDF, platelet deficiency, enhanced fibrinogen turnover, and paracoagulation tests showing disseminated intravascular coagulation were frequent in both groups. Platelet deficiency was significantly more frequent in group A (64.9% of cases) than in group B (37.5%). Patients in the latter group received small subcutaneous doses of heparin from the moment of admission.

Blood Cell Count

Progestational agents and blood coagulation. VII. Thromboembolic and other complications of oral contraceptive therapy in relationship to pretreatment levels of blood coagulation factors: summary report of a ten-year study.

During a ten-year period, 348 women were studied for a total of 5,877 patient months in four separate studies relating oral contraceptives to changes in hematologic parameters. Significant increases in certain factors of the blood coagulation and fibrinolysin systems (factors I,II,VII,VIII,IX, and X and plasminogen) were observed in the treated groups. Severe complications developed in four patients. All four had an abnormal blood coagulation profile, suggesting "hypercoagulability" before initiation of therapy. Some of these findings represented the most extreme abnormalities seen in the entire group of patients; some increased further during therapy. One of these patients developed a myocardial infarction before receiving any medication, shortly after the base-line values were obtained. One patient developed retinopathy 19 months after she began therapy, and another developed thrombophlebitis after 27 months of therapy. The fourth patient developed thrombophlebitis 14 days after initiation of contraceptive therapy. All four patients were of the A or AB blood group. Previous studies suggested the possiblility of increased propensity for thromboembolic episodes in patients possessing the A antigen. It appears from these data that hematologic work-ups may be useful in women who are about to start long-term oral contraceptive therapy.

Adult

[Coagulation-physiological studies on the prevention of thromboembolism with dextran 60. II. Changes in coagulation and fibrinolysis].

The postoperative behavior of different parameters of coagulation and fibrinolysis have been studied in three groups of 20 patients each. Group A got only 4-hydroxycumarin, group B 500 ml Dextran 60 intraoperatively in addition to that, group C 500 ml Dextran 60 during surgery and on the 1., 2., 4., 7. and 10. postoperative day. The results show that the hypercoagulability which occurs immediately after surgery can be prevented by infusion of Dextran 60. On the other hand there is no evidence that Dextran 60 may cause a consumptive coagulability. There is only little influence on fibrinolysis, so that no defect of haemostasis can be expected. So it is possible to use Dextran 60 both for bridging over the phase of early embolism after surgery until the change to other anticoagulants and as a substance which can be applicated for a longer period of time in prophylaxis of thromboembolism. It is referred to the additional properties of Dextran 60 in prevention of thrombosis due to reduction of blood viscosity and improvement of microcirculation.

4-Hydroxycoumarins

Bedside monitoring of anti-coagulation under LDL apheresis by means of aPTT testing with a coagulation monitor.

Optimally adjusted anticoagulation under LDL apheresis is essential for successful treatment: Excessive anticoagulation exposes the outpatient to the risk of uncontrolled hemorrhage, insufficient anticoagulation may shorten the duration of utilization of the immune-adsorption columns. A new device (coagulation monitor 512, Ciba Corning) allows individual adaptation of dosage and timing of heparin application by modifying the standard schedule (5,000 IU intravenously before treatment, 2,000 IU/h continuously). APTT was measured before and after application of heparin and then at 30-min intervals both by the coagulation monitor and by conventional laboratory methods; the respective heparin concentration was determined in addition. The correlation coefficient between the heparin concentration and both the monitor-derived and the laboratory-derived aPTT was 0.811 and 0.590, respectively. An explanation for this finding might be that the monitor avoids the influences induced by subsequent collection and testing of samples associated with laboratory procedures.

Cholesterol, LDL

Coagulation profile and the ethanol gelation test with special reference to components consumed during coagulation.

In 753 consequtive blood samples (from the same number of patients) routinely examined for coagulation abnormalities, a positive ethanol gelation test was found in 160. In 7 samples with plasma fibrinogen below 150 mg/100 ml and a positive test, other laboratory signs of consumption coagulopathy (low thrombocyte count, low factor V, low antithrombin III, large amounts of FDP in serum and great discrepancies between Normotest and Thrombotest) were regularly observed. Also at normal or high fibrinogen levels, a positive ethanol gelation test was more frequently associated with low thrombocyte counts, low factor V and Normotest/Thrombotest discrepancy than was a negative test. In 46% of the samples with a positive test, fibrinogen was higher than 500 mg/100 ml (versus 4% in those with a negative test). In one-third of these samples, all other parameters gave normal results.

Blood Coagulation Disorders

Alterations in the coagulation and fibrinolysis system in pregnancy, labour and puerperium, with special reference to a possible transitory state of intravascular coagulation during labour.

Various tests of hemostasis were carried out during pregancy, labour and the puerperium in a group of 259 women. Determinations were carried out in the 1st, 2nd and 3rd trimesters, in the period of dilatation, the expulsion period, the period of expulsion of the placenta and the immediate postpartum period of labour and on each of the first 5 days of the puerperium. It was confirmed that during pregnancy there is an elevation of the fibrinogen degradation products (FDP) levels with a proportional increase in the numbers of positive protamine sulfate and ethanol tests. The proportion of positive protamine sulfate and ethanol tests reaches a maximum in the expulsion of the placenta coinciding with the presence of soluble complexes heavier than fibrinogen as detected by polyacrylamide gel electrophoresis and by column chromatography. All this indicates that there is a transitory intravascular coagulation produced during labour reaching its maximum at the time of birth and tending to become normalized in the first few days of the puerperium.

Blood Coagulation