Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “HEMOSTATICS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources
PubMed1983

Molecular markers of hemostatic disorders: implications in the diagnosis and therapeutic management of thrombotic and bleeding disorders.

With current technological advances, it is now possible to measure in less than 50 microL of plasma picomolar amounts of circulating products of platelet activation, products of protease activation related to coagulation and fibrinolytic pathways, and prostaglandin metabolites formed during a physiologic or pathologic process. Most of these markers, which circulate in blood in nanogram or picogram amounts per milliliter during or after pathologic activation, provide pertinent information on the status of a patient in terms of specificity and early detection, and will be of crucial value in the diagnosis of hemostatic defects and the management of newer antithrombotic drugs that cannot be monitored by currently available assays. Currently, 125I- and 3H-based simple radioimmunoassays are available for platelet factor 4, beta-thromboglobulin, fibrinopeptide A, B beta 15-42 related peptides, thromboxane B2, and the prostaglandins 6-keto-PGF1 alpha and PGE2. Nonisotopic methods such as enzyme-linked immunosorbent assays and fluoroimmunoassays are being developed. Serotonin and ADP, products of platelet activation, are measurable by liquid-chromatographic, immunoenzymatic, and spectrophotofluorometric methods. Analytical methods for fibrin split products (fragments D and E) and serine protease inhibitor complexes such as thrombin-antithrombin-III, factor Xa-antithrombin-III, and kallikrein-C1-esterase are also being developed. We have evaluated all of these methods and found them to be very sensitive to those components of endogenous activation of the hemostatic system listed above.

Blood Coagulation Disorders↗
PubMed1982

Postoperative hemostatic profile in relation to gram-negative septicemia.

Gram-negative septicemia presents a particular problem in the ICU. Septicemia is usually diagnosed by fever, chills, and shock. Results of blood cultures become available a few days later. Major surgery induced a marked decline in antithrombin III (AT III) and plasminogen (PLG) to a mean level of 0.60 U/ml (normal value: 0.80-1.40 U/ml) on the 2nd and 3rd postoperative days. Around the 5th postop day, these values again attained mean preoperative levels. Seventy-six surgical ICU patients were investigated preoperatively and for 10 days postoperatively to relate postop septicemia to changes in the hemostatic profile. In 15 patients with gram-negative septicemia verified by positive culture, AT III and PLG barely recovered from the postop decrease and remained significantly lower (p less than 0.05) after the 3rd postop day, compared to 61 surgical ICU patients without septicemia. The behavior of alpha 2antiplasmin (alpha 2AP) values was equal in both groups. This difference in hemostatic profile preceded the clinical manifestations of septicemia and the results of blood culture by several days. Leucocyte or platelet counts provided no reliable information on the early development of septicemia in these surgical patients. It is concluded that persistent low plasma AT III and PLG levels in the postop phase are early indicators of a developing gram-negative septicemia.

Adolescent↗
PubMed1980

[The hemostatic assistance after sub-total or total hepatectomy in the dog (author's transl)].

After subtotal (90%) or total hepatectomy in the dog, coagulation disturbances appear early and exclude survival beyond 40 hours. These disturbances are the result of a fall in the synthesis of coagulation factors, but may also reflect a consumption syndrome. The ensuing clinical finding is an intravascular coagulation which can give way to fibrinolysis. A substitutive therapy aiming to replace the missing factors and avoid or prevent an eventual consumption thus appears necessary. The hemostatic disturbances after subtotal or total hepatectomy in the dog can be totally corrected by a substitutive therapy based on fresh frozen plasma. The first hepatic segment (caudate lobe) cannot insure by itself the coagulation functions during the first 4 post-op days. The hemostatic assistance is an other step towards the treatment of hepatic insufficiency. It must become an integral part of existing artificial liver support.

Animals↗
PubMed1980

Hemostatic changes following rattlesnake (Crotalus viridis helleri) venom in the dog.

Hemostatic changes were observed in mongrel dogs (N = 5, 18.6 26.7 kg) following and i.v. LD20 (50 microgram/kg) of rattlesnake (Crotalus viridis helleri) venom. Venom produced thrombocytopenia within 5 min and fibrinogen was significantly reduced at 240 min. In addition, the presence of fibrin split products, a positive protamine sulfate test and a decrease in the euglobulin lysis time, suggest that fibrinogenolysis and fibrinolysis are initiated shortly after venom. Prothrombin and partial thromboplastin times were little affected. Examination of bone marrow revealed vacuolization and a reduction in the number of megakaryocytes. These data suggest that this dose of rattle-snake venom produces hemostatic defects by the destruction of fibrinogen and circulating platelets.

Animals↗
PubMed1995

Activation of the hemostatic mechanism during thrombolysis in patients with unstable angina pectoris.

In patients with myocardial infarction, thrombolytic therapy induces a paradoxical activation of the hemostatic mechanism. In patients with unstable angina, the effect of thrombolysis on the coagulation cascade is unknown. We prospectively measured the plasma concentrations of prothrombin fragment 1 + 2 and fibrinopeptide A in consecutive patients with unstable angina randomized to receive placebo alone (n = 23), streptokinase 1,500,000 IU over 1 hour followed by a 48-hour placebo infusion (n = 21), or streptokinase 250,000 over 1 hour followed by a continuous infusion of 100,000 IU per hour over 48 hours (n = 20). All the patients received intravenous heparin for 72 hours. The plasma levels of the different markers were measured at baseline, 90 minutes, 24 hours, and 48 hours after the start of therapy. The median baseline plasma concentrations of prothrombin fragment 1 + 2 and fibrinopeptide A were similar in the three treatment groups. In comparison with placebo, an increase in plasma prothrombin fragment 1 + 2 and fibrinopeptide A, was observed after 90 minutes in the two groups receiving thrombolysis. After 24 and 48 hours, the prothrombin fragment 1 + 2 levels remained significantly higher only in the patients receiving the 48-hour streptokinase infusion. In patients with unstable angina, thrombolytic therapy induces an activation of the hemostatic mechanism, despite concomitant heparin administration; in those receiving a prolonged streptokinase infusion, the activation of coagulation persists for as long as the drug is administered.

Aged↗
PubMed1995

Loss of blast cell procoagulant activity and improvement of hemostatic variables in patients with acute promyelocytic leukemia administered all-trans-retinoic acid.

All-trans-retinoic acid (ATRA) induces complete remission (CR) in up to 90% of acute promyelocytic leukemia (APL) patients with rapid amelioration of the bleeding syndrome. Previous studies indicate that ATRA treatment in vitro of the APL NB4 cell line can affect their procoagulant activity (PCA). To assess whether ATRA has this effect also in vivo, we prospectively studied the PCA of bone marrow blasts from APL patients on therapy with ATRA alone or associated with chemotherapy. Samples were obtained before, during, and after ATRA. To characterize the coagulopathy, we measured a series of plasma hemostatic variables before and during the first two weeks of therapy, as follows: (1) markers of hypercoagulability; (2) natural anticoagulants; (3) fibrinolysis proteins; and (4) elastase. The results by enzymatic and immunologic methods show that both total (tissue factor-like) and factor VII-independent (cancer procoagulant-like) blast cell PCAs, present before therapy, were reduced during (69% and 65% decrement, respectively) and virtually undetectable after ATRA. The plasma hemostatic assessment of patients before treatment was elevated hypercoagulability markers, low mean protein C, normal fibrinolysis proteins, and increased elastase. After starting ATRA, hypercoagulability markers were reduced within 4 to 8 days, protein C augmented, the overall fibrinolytic balance was unmodified, and elastase remained elevated. These results were not different either with or without chemotherapy and are consistent with the clinical findings of rapid improvement of the coagulopathy.

Adolescent↗
PubMed1995

Systemic and colonic venous hemostatic alterations in horses during low-flow ischemia and reperfusion of the large colon.

Twenty-four horses were randomly allocated to 3 groups. All horses underwent a ventral midline celiotomy, and the large colon was exteriorized and instrumented. Group-1 horses served as sham-operated controls, group-2 horses underwent 6 hours of colonic ischemia, and group-3 horses were subjected to 3 hours of ischemia and 3 hours of reperfusion. Baseline blood samples were collected, then low-flow colonic ischemia was induced in horses of groups 2 and 3 by reducing colonic arterial blood flow to 20% of baseline. All horses were monitored for 6 hours. Citrated systemic venous (SV) blood samples were collected from the main pulmonary artery, and colonic venous (CV) samples were collected from the colonic vein draining the ventral colon. Samples were collected at 0, and 2, 3, 3.25, 4, and 6 hours for determination of one-stage prothrombin time, activated partial thromboplastin time, antithrombin III activity, and fibrinogen concentration. Data were analyzed statistically, using two-way ANOVA for repeated measures, and post-hoc comparisons were made by use of Student Newman Keul's test. Statistical significance was set at P < 0.05. There were significant decreases in all hemostatic variables by 2 hours in SV and CV samples from horses of all 3 groups, but there were no differences among the 3 groups for any of these variables. These hemostatic alterations could have been secondary to a hypercoagulable state or to fluid therapy-induced hemodilution. Colonic ischemia-reperfusion was not the cause of these alterations because these alterations also were observed in the sham-operated control horses. Significant temporal alterations existed even after accounting for the hemodilution.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1993

Hemostatic activation during cardiopulmonary bypass with different aprotinin dosages in pediatric patients having cardiac operations.

The effect of high-dose aprotinin treatment on hemostatic activation during cardiopulmonary bypass in pediatric patients having cardiac operations was investigated. Sixty patients weighing less than 10 kg undergoing cardiac operations for different types of congenital heart diseases were studied: 20 patients were treated with aprotinin 2 x 15,000 KIU/kg, 20 patients with 2 x 30,000 KIU/kg, and 20 patients without aprotinin treatment served as the control group. Different split products of fibrinogen and/or fibrin and the fibrinolytic activity on fibrin plates were measured to assess fibrinolytic activation. F1/F2 prothrombin fragments, thrombin-antithrombin III-complex, and fibrin monomers were measured to estimate thrombin activation. There was a significant dose-dependent reduction in fibrin-fibrinogen split product formation during cardiopulmonary bypass: In the high-dose aprotinin group the concentration of the split products at the end of bypass was 1.5 +/- 0.6 micrograms/ml, compared with 3.4 +/- 3.0 micrograms/ml in the low-dose aprotinin group and 6.7 +/- 3.5 micrograms/ml in the control group (p < 00.5). Fibrinolytic activation on fibrin plates was also significantly reduced by aprotinin. Fibrin monomer formation was significantly diminished at the end of cardiopulmonary bypass in the high-dose group: 9.2 +/- 5.2 micrograms/ml compared with 21.6 +/- 14 micrograms/ml in the control group (p < 00.5). Elastase in complex with alpha 1-protease inhibitor at the end of bypass was increased to the same amount in the three groups: 784 +/- 278 ng/mL (control group), 693 +/- 189 ng/ml (low-dose aprotinin), and 719 +/- 270 ng/mL (high dose aprotinin) (no significant difference). Blood loss 6 hours postoperatively was significantly (p < 00.5) less in the high-dose group (99 +/- 32 ml/m2) than in the control group (164 +/- 87 ml/m2; low-dose group: 160 +/- 106 ml/m2). These observations suggest an attenuation of hemostatic activation during cardiopulmonary bypass with less plasmin formation and, because of inhibition of contact activation, less thrombin generation with aprotinin treatment. Thus the thrombotic-thrombolytic equilibrium is kept more balanced after cardiopulmonary bypass. High-dose aprotinin treatment is recommended for pediatric patients undergoing cardiac operations.

Antithrombin III↗
PubMed1994

[Effect of shear stress on hemostatic regulation in endothelium].

The vascular endothelium plays a pivotal role in regulating the hemostatic system. Various cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor (TNF) are known to perturb endothelial cells to reduce antithrombogenicity. On the other hand, blood flow has been shown to affect the endothelium to maintain its antithrombogenicity under some levels of shear stress in the laminar flow system. We examined the role of hemodynamic forces on the vascular system under cytokine stimulation using a cone-plate type viscometer. Treatment of endothelial cells with either IL-1 beta or TNF-alpha under static conditions increased PAI-1, vWF and prostacyclin release, while t-PA secretion was unchanged. When cells were exposed to steady shear stress of 0, 6, 12, 18 and 24 dyne/cm2, the release of t-PA, t-PA-PAI complex and prostacyclin elevated with the increase of shear stress intensity, while a gradual decrease of total PAI-1 secretion was observed and vWF secretion was unchanged. On the contrary, active PAI-1 secretion was significantly decreased under the shear stress of over 18 dyne/cm2. Interestingly, cytokines, which did not affect t-PA secretion of resting cells, increased the t-PA secretion and had an additive effect on prostacyclin secretion with shear stress under the shear stress of over 18 dyne/cm2. PAI-1 elevation induced by cytokines was markedly abolished under the same shear forces. No additive effect was observed in the secretion of vWF. Thus, shear stress attenuates the alteration of the balance in the fibrinolytic and coagulation system induced by cytokines. These findings clearly indicate that hemodynamic forces play a crucial role in regulating the hemostatic activity in vivo.

Blood Coagulation↗
PubMed1995

[Activation of endothelium-dependent hemostatic factors following bone marrow transplantation].

Changes in hemostatic factors after bone marrow transplantation (BMT), with or without thrombotic complications, have already been described. The endothelium seems to be actively involved in such processes. Over a period of 2 years we evaluated various hemostatic factors, associated or not with endothelial stimulation, in 44 patients with BMT (40 leukemias and 4 aplastic anemias). Factor VIII activity (VIII:C), von Willebrand factor antigen (vWF:Ag), tissue plasminogen activator antigen (tPA), plasminogen activator inhibitor activity (PAI-1), antithrombin III, protein C and protein S were assayed before and 1, 3, 6, 12, 18, and 24 months after BMT. Factor VIII:C, vWF and tPA were found to be significantly increased 1-6 months after BMT, returning to normal later. Patients with acute graft versus host disease, fever or cyclosporin treatment had significantly higher VIII:C, vWF and tPA. The increase in these factors implies lasting stimulation of their release and/or synthesis from endothelial cells that is enhanced by some complications of BMT. The degree and character of these changes could favor activation of thrombotic processes.

Adolescent↗
PubMed1993

[Lipid peroxides and the hemostatic system in myocardial infarct complicated by arrhythmia].

A comprehensive study of the levels of lipid peroxidation products and hemostatic parameters was made in 73 patients with various clinical courses of myocardial infarction by using current clinical and laboratory techniques. The patients were demonstrated to have a substantial increase in lipid peroxides and in the activity of glutathione peroxidase, an antioxidative enzyme, which was accompanied by hemostatic disorders. The biochemical changes revealed reflect the severity of the disease and may promote the occurrence and deterioration of cardiac arrhythmias in patients with myocardial infarction.

Arrhythmias, Cardiac↗
PubMedDate not supplied

[Hemostatic changes in patients with tumors of the maxillofacial area].

To study hemostatic impairments in patients with maxillofacial tumors, 131 patients and 30 healthy subjects were examined. The patients were found to develop early hemostatic changes which appeared as a latent DIC syndrome. The mobility of the physiological system of PASA permits the equilibrium of coagulative and anticoagulative mechanisms to be preserved to a definite extent and fairly long. The changes were detected during the formation of prothrombinase, thrombin and during fibrin formation and stabilization in the fibrinolytic system. Hypercoagulation typical of the DIC syndrome at the early stages of tumor was followed by consumption coagulopathic signs and profuse bleeding risk at the T4 and N3 stages.

Adolescent↗
PubMed1993

[Hemostatic factors of endothelial origin in major vascular pathology].

There is an altered hemostatic balance in vascular-based diseases. The aim of this study was to compare a group (no. = 38) of vascular patients (aortic aneurysm, carotid obstructions arteriopathies of lower limbs) and a control group (no. = 40) and assess variations in the following endothelial factors: tPA, PAI1, vWf, fibronectin and dimer D, in differentiated degrees according to the type of pathology. These were the indicative signs of endothelial mobilization resulting in the renewed continuity of the stratum with the formation of a hemostatic plug. vWf was found to be particularly significant as a marker of an ongoing atheromasic process and its extension to various vascular districts.

Adult↗
PubMedDate not supplied

[Clinical significance of the determination of several hemostatic parameters in the lacrimal fluid of patients with vascular diseases of the retina].

Clinicolaboratory studies of 92 patients with vascular diseases of the retina (retinal vein thrombosis, central chorioretinal dystrophy, retinal hypertensive angiosclerosis) were carried out to assess hemorheologic parameters (platelet and red cell aggregation coefficients, blood viscosity). In parallel with this, lacrimal fluid was analyzed for hemostatic parameters, plasminogen and antithrombin III. A marked increase of plasminogen and antithrombin III levels was found in the lacrimal fluid of patients with retinal vein thrombosis, this increase correlating with pathologic shifts in the studied rheologic characteristics. Central chorioretinal dystrophy and retinal hypertensive angiosclerosis were associated with shifts in some rheologic characteristics. Hence, measurements of lacrimal fluid hemostatic parameters plasminogen and antithrombin III in patients with retinal vascular diseases help assess blood rheology.

Adult↗
PubMedDate not supplied

Acute phase reaction and the hemostatic balance.

Data in the literature as well as authors own observations concerning a possible relationship between the acute phase reaction and changes of the hemostatic variables, which may favour or trigger a thrombotic event, are reviewed. Acute phase reaction is usually accompanied by increased plasma levels of fibrinogen, von Willebrand factor and clotting factor VIII, while endothelial cells in culture added proinflammatory cytokines were found to express tissue factor activity, to release von Willebrand factor and to increase the production of plasminogen activator inhibitor. Evidence is also provided that inflammation would lead to an increase of plasma antithrombin III while the protein C system is down regulated. It is also considered that the above-mentioned changes of hemostatic variables would favour the local deposition of fibrin and platelets while attempting to prevent an intravascular dissemination of fibrin formation.

Acute-Phase Proteins↗
PubMed1996

[The modulation of hemostatic reactions in vitro and in vivo by representatives of regulatory peptide families].

Data available in the literature and the author's own findings of the effects of regulatory peptide (RP) and their analogues are summarized. MIF, TRH, and its analog PR-546, the paraopioid RP, leuenkephalin, dalargin, the ACTH analogue Semax, tafcin, thymosine, interleukin-1, vasopressin, oxytocin, bradykinin, defencin, and some proline-containing oligopeptides, such as Pro-Gly, Gly-Pro, Trp-Pro, Pro-Gly-Pro, Gly-Pro-Gly-Gly were studied. A complex of in vitro and in vivo tests identified three groups of RP: 1) neutral ones as to the hemostatic reactions studied; 2) stimulants of hypercoagulation and fibrin polymerization; 3) inhibitors of blood coagulation, increased fibrinolysis, and fibrin demopolymerization. The fibrinolytic and antithrombotic effects of Semax (in vivo), the procoagulative action of defencin, and the enhanced anticoagulant effects in the combinations of Semax-heparin and tafcin (in vivo) attract particular attention. Semax alone and in combination with heparin is recommended for clinical studies in respective hemostatic abnormalities.

Administration, Intranasal↗
PubMed1997

Mild hyperhomocysteinemia and hemostatic factors in patients with arterial vascular diseases.

Mild hyperhomocysteinemia, due to genetic or to environmental factors, is now recognized as a risk factor for premature arterial disease, including peripheral arterial occlusion, thrombotic stroke and myocardial infarction. It is defined by either an increased level of fasting homocysteine or by an increased level after loading with methionine, which is more frequently altered than the former. We studied the hemostatic parameters in 88 patients with premature arterial disease (mean age 43 +/- 11 years). We confirmed previously known hemostatic alterations described in vascular patients when compared to controls, but found that, among patients, some of these parameters were more altered in hyperhomocysteinemic patients. When fasting homocysteine was increased, higher alterations were found in factors VIIIc, von Willebrand and thombin-antithrombin complexes were more elevated. When post-methionine load homocysteine was increased, alterations in fibrinolytic parameters were more pronounced.

Adult↗
PubMed1997

Oncotic, hemodilutional, and hemostatic effects of isotonic saline and hydroxyethyl starch solutions in clinically normal ponies.

OBJECTIVE: To evaluate the oncotic, hemodilutional, and hemostatic effects of IV infusions of a large volume of isotonic saline solution and 2 doses of 6% hydroxyethyl starch (HES) in clinically normal ponies. ANIMALS: 12 adult ponies. PROCEDURE: Ponies were assigned to 3 treatment groups and received the following IV infusions: 80 ml of 0.9% sodium chloride/kg; 10 ml of 6% HES (in 0.9% sodium chloride)/kg; or 20 ml of 6% HES (in 0.9% sodium chloride)/kg. Blood samples were collected for determination of colloid oncotic pressure (COP), PCV, plasma total protein concentration, platelet count, von Willebrand factor antigen (vWf:Ag) activity, fibrinogen concentration, prothrombin time, activated partial thromboplastin time (APTT), and factor VIII coagulant (FVIII:C) activity. A rocket immunoelectrophoretic procedure was used for determination of vWf:Ag activity. A modification of the APTT assay was used for determination of FVIII:C activity. Cutaneous bleeding time was determined, using a template method. RESULTS: Mean COP was persistently increased over baseline values in the face of hemodilution in HES-treated ponies. Prothrombin time, APTT, and fibrinogen concentrations decreased after infusions and vWf:Ag and FVIII:C activities were decreased in dose-dependent manner in HES-treated ponies. Though cutaneous bleeding time was not significantly affected in ponies of any group, a trend toward prolongation of bleeding time was evident in ponies receiving 20 ml of HES/kg. This trend appeared to be associated with marked decrement in vWf:Ag activity at this dosage. CONCLUSIONS AND CLINICAL RELEVANCE: Infusion of HES in clinically normal ponies increases COP, and exerts dose-dependent hemodilutional effects and dose-dependent effects on specific hemostatic variables. Thus, HES may be useful for resuscitative fluid treatment of horses.

Animals↗