Fibrin: A protein derived from FIBRINOGEN in the presence of THROMBIN, which forms part of the blood clot.Fibrin Tissue Adhesive: An autologous or commercial tissue adhesive containing FIBRINOGEN and THROMBIN. The commercial product is a two component system from human plasma that contains more than fibrinogen and thrombin. The first component contains highly concentrated fibrinogen, FACTOR VIII, fibronectin, and traces of other plasma proteins. The second component contains thrombin, calcium chloride, and antifibrinolytic agents such as APROTININ. Mixing of the two components promotes BLOOD CLOTTING and the formation and cross-linking of fibrin. The tissue adhesive is used for tissue sealing, HEMOSTASIS, and WOUND HEALING.Fibrin Fibrinogen Degradation Products: Soluble protein fragments formed by the proteolytic action of plasmin on fibrin or fibrinogen. FDP and their complexes profoundly impair the hemostatic process and are a major cause of hemorrhage in intravascular coagulation and fibrinolysis.Fibrinogen: Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.Fibrinolysis: The natural enzymatic dissolution of FIBRIN.Tissue Adhesives: Substances used to cause adherence of tissue to tissue or tissue to non-tissue surfaces, as for prostheses.Fibrinopeptide B: Two small peptide chains removed from the N-terminal segment of the beta chains of fibrinogen by the action of thrombin. Each peptide chain contains 20 amino acid residues. The removal of fibrinopeptides B is not required for coagulation.Blood Coagulation: The process of the interaction of BLOOD COAGULATION FACTORS that results in an insoluble FIBRIN clot.Batroxobin: A proteolytic enzyme obtained from the venom of fer-de-lance (Bothrops atrox). It is used as a plasma clotting agent for fibrinogen and for the detection of fibrinogen degradation products. The presence of heparin does not interfere with the clotting test. Hemocoagulase is a mixture containing batroxobin and factor X activator. EC 3.4.21.-.Fibrinopeptide A: Two small peptide chains removed from the N-terminal segment of the alpha chains of fibrinogen by the action of thrombin during the blood coagulation process. Each peptide chain contains 18 amino acid residues. In vivo, fibrinopeptide A is used as a marker to determine the rate of conversion of fibrinogen to fibrin by thrombin.Factor XIII: A fibrin-stabilizing plasma enzyme (TRANSGLUTAMINASES) that is activated by THROMBIN and CALCIUM to form FACTOR XIIIA. It is important for stabilizing the formation of the fibrin polymer (clot) which culminates the coagulation cascade.Fibrinolysin: A product of the lysis of plasminogen (profibrinolysin) by PLASMINOGEN activators. It is composed of two polypeptide chains, light (B) and heavy (A), with a molecular weight of 75,000. It is the major proteolytic enzyme involved in blood clot retraction or the lysis of fibrin and quickly inactivated by antiplasmins.Plasminogen: Precursor of plasmin (FIBRINOLYSIN). It is a single-chain beta-globulin of molecular weight 80-90,000 found mostly in association with fibrinogen in plasma; plasminogen activators change it to fibrinolysin. It is used in wound debriding and has been investigated as a thrombolytic agent.Fibrinogens, Abnormal: Fibrinogens which have a functional defect as the result of one or more amino acid substitutions in the amino acid sequence of normal fibrinogen. Abnormalities of the fibrinogen molecule may impair any of the major steps involved in the conversion of fibrinogen into stabilized fibrin, such as cleavage of the fibrinopeptides by thrombin, polymerization and cross-linking of fibrin. The resulting dysfibrinogenemias can be clinically silent or can be associated with bleeding, thrombosis or defective wound healing.Factor XIIIa: Activated form of FACTOR XIII, a transglutaminase, which stabilizes the formation of the fibrin polymer (clot) culminating the blood coagulation cascade.Thrombin: An enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.Ancrod: An enzyme fraction from the venom of the Malayan pit viper, Agkistrodon rhodostoma. It catalyzes the hydrolysis of a number of amino acid esters and a limited proteolysis of fibrinogen. It is used clinically to produce controlled defibrination in patients requiring anticoagulant therapy. EC 3.4.21.-.alpha-2-Antiplasmin: A member of the serpin superfamily found in plasma that inhibits the lysis of fibrin clots which are induced by plasminogen activator. It is a glycoprotein, molecular weight approximately 70,000 that migrates in the alpha 2 region in immunoelectrophoresis. It is the principal plasmin inactivator in blood, rapidly forming a very stable complex with plasmin.Tissue Plasminogen Activator: A proteolytic enzyme in the serine protease family found in many tissues which converts PLASMINOGEN to FIBRINOLYSIN. It has fibrin-binding activity and is immunologically different from UROKINASE-TYPE PLASMINOGEN ACTIVATOR. The primary sequence, composed of 527 amino acids, is identical in both the naturally occurring and synthetic proteases.Afibrinogenemia: A deficiency or absence of FIBRINOGEN in the blood.Thrombosis: Formation and development of a thrombus or blood clot in the blood vessel.Plasminogen Activators: A heterogeneous group of proteolytic enzymes that convert PLASMINOGEN to FIBRINOLYSIN. They are concentrated in the lysosomes of most cells and in the vascular endothelium, particularly in the vessels of the microcirculation.Gels: Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.Thrombin Time: Clotting time of PLASMA mixed with a THROMBIN solution. It is a measure of the conversion of FIBRINOGEN to FIBRIN, which is prolonged by AFIBRINOGENEMIA, abnormal fibrinogen, or the presence of inhibitory substances, e.g., fibrin-fibrinogen degradation products, or HEPARIN. BATROXOBIN, a thrombin-like enzyme unaffected by the presence of heparin, may be used in place of thrombin.Aminocaproic Acid: An antifibrinolytic agent that acts by inhibiting plasminogen activators which have fibrinolytic properties.Disseminated Intravascular Coagulation: A disorder characterized by procoagulant substances entering the general circulation causing a systemic thrombotic process. The activation of the clotting mechanism may arise from any of a number of disorders. A majority of the patients manifest skin lesions, sometimes leading to PURPURA FULMINANS.Fibrin Modulating Agents: Agents that affect the function of FIBRIN in BLOOD COAGULATION. They used as COAGULANTS for HEMORRHAGE or ANTICOAGULANTS for THROMBOSIS.Urokinase-Type Plasminogen Activator: A proteolytic enzyme that converts PLASMINOGEN to FIBRINOLYSIN where the preferential cleavage is between ARGININE and VALINE. It was isolated originally from human URINE, but is found in most tissues of most VERTEBRATES.Blood Coagulation Tests: Laboratory tests for evaluating the individual's clotting mechanism.Blood Platelets: Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.Hemostatics: Agents acting to arrest the flow of blood. Absorbable hemostatics arrest bleeding either by the formation of an artificial clot or by providing a mechanical matrix that facilitates clotting when applied directly to the bleeding surface. These agents function more at the capillary level and are not effective at stemming arterial or venous bleeding under any significant intravascular pressure.Thromboplastin: Constituent composed of protein and phospholipid that is widely distributed in many tissues. It serves as a cofactor with factor VIIa to activate factor X in the extrinsic pathway of blood coagulation.Nephelometry and Turbidimetry: Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.Hemostasis: The process which spontaneously arrests the flow of BLOOD from vessels carrying blood under pressure. It is accomplished by contraction of the vessels, adhesion and aggregation of formed blood elements (eg. ERYTHROCYTE AGGREGATION), and the process of BLOOD COAGULATION.Antifibrinolytic Agents: Agents that prevent fibrinolysis or lysis of a blood clot or thrombus. Several endogenous antiplasmins are known. The drugs are used to control massive hemorrhage and in other coagulation disorders.Blood Coagulation Disorders: Hemorrhagic and thrombotic disorders that occur as a consequence of abnormalities in blood coagulation due to a variety of factors such as COAGULATION PROTEIN DISORDERS; BLOOD PLATELET DISORDERS; BLOOD PROTEIN DISORDERS or nutritional conditions.Transglutaminases: Transglutaminases catalyze cross-linking of proteins at a GLUTAMINE in one chain with LYSINE in another chain. They include keratinocyte transglutaminase (TGM1 or TGK), tissue transglutaminase (TGM2 or TGC), plasma transglutaminase involved with coagulation (FACTOR XIII and FACTOR XIIIa), hair follicle transglutaminase, and prostate transglutaminase. Although structures differ, they share an active site (YGQCW) and strict CALCIUM dependence.Antithrombin III: A plasma alpha 2 glycoprotein that accounts for the major antithrombin activity of normal plasma and also inhibits several other enzymes. It is a member of the serpin superfamily.Microscopy, Electron, Scanning: Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.Laboratories: Facilities equipped to carry out investigative procedures.Diagnostic Techniques and Procedures: Methods, procedures, and tests performed to diagnose disease, disordered function, or disability.Menu PlanningPlasticizers: Materials incorporated mechanically in plastics (usually PVC) to increase flexibility, workability or distensibility; due to the non-chemical inclusion, plasticizers leach out from the plastic and are found in body fluids and the general environment.Menorrhagia: Excessive uterine bleeding during MENSTRUATION.Menstruation: The periodic shedding of the ENDOMETRIUM and associated menstrual bleeding in the MENSTRUAL CYCLE of humans and primates. Menstruation is due to the decline in circulating PROGESTERONE, and occurs at the late LUTEAL PHASE when LUTEOLYSIS of the CORPUS LUTEUM takes place.Menstrual Hygiene Products: Personal care items used during MENSTRUATION.Pit and Fissure Sealants: Agents used to occlude dental enamel pits and fissures in the prevention of dental caries.Catgut: Sterile collagen strands obtained from healthy mammals. They are used as absorbable surgical ligatures and are frequently impregnated with chromium or silver for increased strength. They tend to cause tissue reaction.Periodontics: A dental specialty concerned with the histology, physiology, and pathology of the tissues that support, attach, and surround the teeth, and of the treatment and prevention of disease affecting these tissues.Mandibular Reconstruction: The physical restoration of oromandibular defects.Piezosurgery: The use of HIGH-ENERGY SHOCK WAVES, in the frequency range of 20-30 kHz, to cut through mineralized tissue.Gingival Recession: Exposure of the root surface when the edge of the gum (GINGIVA) moves apically away from the crown of the tooth. This is common with advancing age, vigorous tooth brushing, diseases, or tissue loss of the gingiva, the PERIODONTAL LIGAMENT and the supporting bone (ALVEOLAR PROCESS).Los AngelesGingivoplasty: Surgical reshaping of the gingivae and papillae for correction of deformities (particularly enlargements) and to provide the gingivae with a normal and functional form, the incision creating an external bevel. (Dorland, 28th ed)

Comparison of the fibrin-binding activities in the N- and C-termini of fibronectin. (1/2092)

Fibronectin (Fn) binds to fibrin in clots by covalent and non-covalent interactions. The N- and C-termini of Fn each contain one non-covalent fibrin-binding site, which are composed of type 1 (F1) structural repeats. We have previously localized the N-terminal site to the fourth and fifth F1 repeats (4F1.5F1). In the current studies, using proteolytic and recombinant proteins representing both the N- and C-terminal fibrin-binding regions, we localized and characterized the C-terminal fibrin-binding site, compared the relative fibrin-binding activities of both sites and determined the contribution of each site to the fibrin-binding activity of intact Fn. By fibrin-affinity chromatography, a protein composed of the 10F1 repeat through to the C-terminus of Fn (10F1-COOH), expressed in COS-1 cells, and 10F1-12F1, produced in Saccharomyces cerevisiae, displayed fibrin-binding activity. However, since 10F1 and 10F1.11F1 were not active, the presence of 12F1 is required for fibrin binding. A proteolytic fragment of 14.4 kDa, beginning 14 residues N-terminal to 10F1, was isolated from the fibrin-affinity matrix. Radio-iodinated 14.4 kDa fibrin-binding peptide/protein (FBP) demonstrated a dose-dependent and saturable binding to fibrin-coated wells that was both competitively inhibited and reversed by unlabelled 14.4 kDa FBP. Comparison of the fibrin-binding affinities of proteolytic FBPs from the N-terminus (25.9 kDa FBP), the C-terminus (14.4 kDa) and intact Fn by ELISA yielded estimated Kd values of 216, 18 and 2.1 nM, respectively. The higher fibrin-binding affinity of the N-terminus was substantiated by the ability of both a recombinant 4F1.5F1 and a monoclonal antibody (mAb) to this site to maximally inhibit biotinylated Fn binding to fibrin by 80%, and by blocking the 90% inhibitory activity of a polyclonal anti-Fn, by absorption with the 25.9 kDa FBP. We propose that whereas the N-terminal site appears to contribute to most of the binding activity of native Fn to fibrin, the specific binding of the C-terminal site may strengthen this interaction.  (+info)

Exosites 1 and 2 are essential for protection of fibrin-bound thrombin from heparin-catalyzed inhibition by antithrombin and heparin cofactor II. (2/2092)

Assembly of ternary thrombin-heparin-fibrin complexes, formed when fibrin binds to exosite 1 on thrombin and fibrin-bound heparin binds to exosite 2, produces a 58- and 247-fold reduction in the heparin-catalyzed rate of thrombin inhibition by antithrombin and heparin cofactor II, respectively. The greater reduction for heparin cofactor II reflects its requirement for access to exosite 1 during the inhibitory process. Protection from inhibition by antithrombin and heparin cofactor II requires ligation of both exosites 1 and 2 because minimal protection is seen when exosite 1 variants (gamma-thrombin and thrombin Quick 1) or an exosite 2 variant (Arg93 --> Ala, Arg97 --> Ala, and Arg101 --> Ala thrombin) is substituted for thrombin. Likewise, the rate of thrombin inhibition by the heparin-independent inhibitor, alpha1-antitrypsin Met358 --> Arg, is decreased less than 2-fold in the presence of soluble fibrin and heparin. In contrast, thrombin is protected from inhibition by a covalent antithrombin-heparin complex, suggesting that access of heparin to exosite 2 of thrombin is hampered when ternary complex formation occurs. These results reveal the importance of exosites 1 and 2 of thrombin in assembly of the ternary complex and the subsequent protection of thrombin from inhibition by heparin-catalyzed inhibitors.  (+info)

Isolation of SMTP-3, 4, 5 and -6, novel analogs of staplabin, and their effects on plasminogen activation and fibrinolysis. (3/2092)

Four novel triprenyl phenol metabolites, designated SMTP-3, -4, -5, and -6, have been isolated from cultures of Stachybotrys microspora IFO 30018 by solvent extraction and successive chromatographic fractionation using silica gel and silica ODS columns. A combination of spectroscopic analyses showed that SMTP-3, -4, -5, and -6 are staplabin analogs, containing a serine, a phenylalanine, a leucine or a tryptophan moiety in respective molecules in place of the N-carboxybutyl portion of the staplabin molecule. SMTP-4, -5, and -6 were active at 0.15 to 0.3 mM in enhancing urokinase-catalyzed plasminogen activation and plasminogen binding to fibrin, as well as plasminogen- and urokinase-mediated fibrinolysis. On the other hand, the concentration of staplabin required to exert such effects was 0.4 to 0.6 mM, and SMTP-3 was inactive at concentrations up to 0.45 mM.  (+info)

Blood-borne tissue factor: another view of thrombosis. (4/2092)

Arterial thrombosis is considered to arise from the interaction of tissue factor (TF) in the vascular wall with platelets and coagulation factors in circulating blood. According to this paradigm, coagulation is initiated after a vessel is damaged and blood is exposed to vessel-wall TF. We have examined thrombus formation on pig arterial media (which contains no stainable TF) and on collagen-coated glass slides (which are devoid of TF) exposed to flowing native human blood. In both systems the thrombi that formed during a 5-min perfusion stained intensely for TF, much of which was not associated with cells. Antibodies against TF caused approximately 70% reduction in the amount of thrombus formed on the pig arterial media and also reduced thrombi on the collagen-coated glass slides. TF deposited on the slides was active, as there was abundant fibrin in the thrombi. Factor VIIai, a potent inhibitor of TF, essentially abolished fibrin production and markedly reduced the mass of the thrombi. Immunoelectron microscopy revealed TF-positive membrane vesicles that we frequently observed in large clusters near the surface of platelets. TF, measured by factor Xa formation, was extracted from whole blood and plasma of healthy subjects. By using immunostaining, TF-containing neutrophils and monocytes were identified in peripheral blood; our data raise the possibility that leukocytes are the main source of blood TF. We suggest that blood-borne TF is inherently thrombogenic and may be involved in thrombus propagation at the site of vascular injury.  (+info)

Use of high-intensity focused ultrasound to control bleeding. (5/2092)

OBJECTIVE: High-intensity focused ultrasound (HIFU) has been shown to be effective in controlling hemorrhage from punctures in blood vessels. The objective of the current study was to investigate the capability of HIFU to stop bleeding after a more severe type of vascular injury, namely longitudinal incisions of arteries and veins. METHODS: The superficial femoral arteries, common femoral arteries, carotid arteries, and jugular veins of four anesthetized pigs were exposed surgically. A longitudinal incision, 2 to 8 mm in length, was produced in the vessel. HIFU treatment was applied within 5 seconds of the onset of the bleeding. The HIFU probe consisted of a high-power, 3.5-MHz, piezoelectric transducer with an ellipsoidal focal spot that was 1 mm in cross section and 9 mm in axial dimension. The entire incision area was scanned with the HIFU beam at a rate of 15 to 25 times/second and a linear displacement of 5 to 10 mm. A total of 76 incisions and HIFU treatments were performed. RESULTS: Control of bleeding (major hemosatsis) was achieved in all 76 treatments, with complete hemostasis achieved in 69 treatments (91%). The average treatment times of major and complete hemostasis were 17 and 25 seconds, respectively. After the treatment, 74% of the vessels in which complete hemostasis was achieved were patent with distal blood flow and 26% were occluded. The HIFU-treated vessels showed a consistent coagulation of the adventitia surrounding the vessels, with a remarkably localized injury to the vessel wall. Extensive fibrin deposition at the treatment site was observed. CONCLUSION: HIFU may provide a useful method of achieving hemostasis for arteries and veins in a variety of clinical applications.  (+info)

Chronic protein undernutrition and an acute inflammatory stimulus elicit different protein kinetic responses in plasma but not in muscle of piglets. (6/2092)

The changes in protein metabolism of severe childhood malnutrition are generally perceived as a metabolic adaptation to chronic protein undernutrition. However, severe malnutrition is invariably accompanied by infections which also have profound effects on protein metabolism. This study aimed to distinguish the effect of protein undernutrition from that of an inflammatory stimulus on muscle and plasma protein synthesis rates. Two groups of five piglets consumed diets containing either 23% or 3% protein for 4 wk. They then were infused intravenously with 2H3-leucine before and 48 h after subcutaneous injections of turpentine to measure the fractional synthesis rates (FSR) of muscle protein and both the FSR and the absolute synthesis rates (ASR) of albumin and fibrinogen. Prior to turpentine injection, compared to control piglets, protein-deficient piglets had significantly lower muscle FSR and plasma concentrations of both albumin and fibrinogen, although only albumin had lower FSR and ASR. Turpentine injection decreased muscle FSR but increased the FSR, ASR and plasma concentrations of both albumin and fibrinogen in control piglets. In protein-deficient piglets, the inflammatory stress caused a further decrease in muscle protein FSR and in plasma albumin concentration despite marked increases in albumin FSR and ASR. Fibrinogen FSR, ASR and plasma concentration were increased. We conclude that protein undernutrition and inflammation elicit the same kinetic response in muscle protein but different kinetic responses in plasma proteins. Furthermore, whereas protein deficiency reduces the plasma albumin pool via a reduction in albumin synthesis, inflammation reduces it through a stimulation of catabolism and/or loss from the intravascular space.  (+info)

Differential regulation of beta1 integrins by chemoattractants regulates neutrophil migration through fibrin. (7/2092)

Chemoattractants differ in their capacity to stimulate neutrophils to adhere to and to migrate through matrices containing fibrin. Formyl methionyl leucyl phenylalanine (fMLP) stimulates neutrophils to adhere closely to, but not to migrate into, fibrin gels. Leukotriene B4 (LTB4) stimulates neutrophils to adhere loosely to and to migrate through fibrin gels. We report that alpha5beta1 integrins regulate the different migratory behaviors on fibrin gels of neutrophils in response to these chemoattractants. fMLP, but not LTB4, activated neutrophil beta1 integrins, as measured by binding of mAb 15/7 to an activation epitope on the beta1 integrins. Antibodies or peptides that block alpha5beta1 integrins prevented fMLP-stimulated neutrophils from forming zones of close apposition on fibrin and reversed fMLP's inhibitory effect on neutrophil chemotaxis through fibrin. In contrast, neither peptides nor antibodies that block beta1 integrins affected the capacity of LTB4-stimulated neutrophils to form zones of loose apposition or to migrate through fibrin gels. These results suggest that chemoattractants generate at least two different messages that direct neutrophils, and perhaps other leukocytes, to accumulate at specific anatomic sites: a general message that induces neutrophils to crawl and a specific message that prepares neutrophils to stop when they contact appropriate matrix proteins for activated beta1 integrins.  (+info)

Malfunction of Bjork-Shiley valve prosthesis in tricuspid position. (8/2092)

Eight months after triple valve replacement with Bjork-Shiley tilting disc valves a patient developed symptoms and signs suggesting malfunction of the prosthesis in the tricuspid position. This was confirmed by echocardiography and angiocardiography, and at operation thedisc of the prosthesis was found to be stuck half-open by fibrin and clot. A further 11 patients with the same tupe of prosthesis in the triscupid position were then studied by phonocardiography and echocardiography. In one of these the prosthesis was found to be stuck and this was confirmed by angiocardiography and surgery. These 2 cases are reported in detail and the findings in the other 10 are discussed. The implications of this high incidence of malfunction of the Bjork-Shiley prosthesis in the tricuspid position are considered. Echocardiography appears to be essential in the follow-up of such patients.  (+info)

  • The Fibrin network is predominantly known for its important role in blood clotting where it provides a scaffold for platelets and other blood cells to form a mature hemostatic plug that seals the injury to the vessel wall, preventing further blood loss and initiating subsequent tissue healing. (
  • By double immunofluorescent labelling systems fibrin deposits were simultaneously stained for α 2 -antiplasmin (α 2 -AP), the main physiological inhibitor of fibrinolysis and in a number of nodular areas they were also labelled for plasmin(ogen). (
  • (
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  • Therefore, we fabricated small modular microbeads formulated from pure fibrin (FIB) and collagen-fibrin (COL-FIB) containing endothelial cells and supportive fibroblasts. (
  • The aims of the present work were (1) to follow fibrin formation and lysis onto the surface of human dermal microvascular endothelial cells (HMEC-1), and (2) to quantify the secretion of fibrinolytic components in the presence of fibrin. (
  • Fibrin clots at different fibrinogen concentrations were formed on top of (model 1) or beneath (model 2) the endothelial cells. (
  • In this study we provide immunomorphological evidence showing that fibrin deposits in lymph nodes with Hodgkin's disease are stabilized and made resistant to fibrinolysis by factor XIII (FXIII) of blood coagulation. (
  • The detection of α 2 -antiplasmin-plasmin complex-neoantigen (α 2 -AP-P-Neo) revealed that α 2 -AP reacted with plasmin, i.e., α 2 -AP covalently linked to fibrin indeed inhibited intratumoral fibrinolysis. (
  • In this study, modular protein microbeads were prepared from pure fibrin (FIB) and collagen-fibrin composites (COL-FIB) using a simple water-in-oil emulsification technique. (
  • Fibrin (also called Factor Ia) is a fibrous, non-globular protein involved in the clotting of blood. (
  • The blood protein fibrin cannot ordinarily enter the brain. (
  • Despite knowledge that fibrin plays a major role in these diseases, researchers have not targeted fibrin because of concerns regarding the protein, and its function elsewhere in the body. (
  • The researchers focused on targeting a small region of the fibrin protein which is involved inactivating the immune system in the brain. (
  • Fibrin is a protein found in the blood. (
  • Fibrin is a protein that circulates through the blood and sticks to the walls of blood vessels. (
  • Dr. Hiroyuki Sumi, a researcher for the Japan Ministry of Education, found that a part of the Japanese fermented soybean food known as natto exhibited strong fibrinolytic activity, meaning simply that it is effective in breaking down fibrin, a protein that is involved in clotting the blood.1 He named the enzyme responsible for this activity 'nattokinase. (
  • The secretion of PAI-1 by HMEC-1 cells was unrelated to the presence of fibrin or RGD, 7 × 10 −6 μg/mL per cell and 5 × 10 −6 μg/mL per cell, for the apical (model 1) and basal clots (model 2), respectively. (
  • HMEC-1 cells influence fibrin formation and dissolution as a function of the fibrin content of clots. (
  • The purpose of this study is to assess platelet and fibrin targeted ultrasound contrast microbubbles' ability to adhere to fresh platelet and platelet poor clots in vitro with the assistance of radiation force. (
  • It was natural for practitioners, looking for effective hemostasis, to look at fibrin as a source of effective hemostatic activity. (
  • Addition of fibrin product to a bleeding surface primed with the other component results in accelerated hemostasis and a sealing effect on the bleeding surface. (
  • Elucidation of the exact mechanisms, involved in these non-hemostasis functions of Fibrin and Fibrinogen, could identify them as therapeutic targets to treat or prevent diseases in which one or more of these (patho) physiological processes play a role. (
  • Extravasal fibrin deposition is frequently observed within and around tumorous tissues and has been implicated in various aspects of tumor growth. (
  • This sensitive and specific assay, distinguishing the products of cross‐linked fibrin from those of fibrinogen and detecting fibrin polymers in plasma, can be achieved without the use of radioactivity. (
  • Degradation of cross-linked fibrin by matrix metalloproteinase 3 (stromelysin 1): hydrolysis of the gamma Gly 404-Ala 405 peptide bond. (
  • The hypothesis that MMPs play a role in the degradation of fibrinogen (Fg) and cross-linked fibrin (XL-Fb) was investigated. (
  • A number of companies have developed devices capable of preparing autologous fibrin and platelet formulations that can be used as sealants, and active mixes of growth factors to aid repair (see link). (
  • This is primarily due to the amount of fibrin being excreted through the bowels. (
  • Cumulative distribution of the absolute change in the amount of fibrin and necrotic tissue at day 14 after treatment with either the PA-based hydrogel or the amorphous hydrogel (b). (
  • The Therapeutic Stage can last anywhere from 3-9 months depending on your body's reaction to enzymes and the excessiveness of the fibrin. (
  • They produced a therapeutic fibrin antibody which accumulated at fibrin-rich areas, protecting against neuroinflammation and neurodegeneration. (
  • Targeting fibrin with immunotherapy is a new approach that could be used to test the therapeutic benefits of suppressing this pathogenic mechanism in multiple disease contexts. (
  • However, no adequate information has been available on the mechanism how intratumoral interstitial fibrin deposits escape a prompt elimination by the fibrinolytic system. (
  • In addition to fibrin deposits FXIII was also found in cellular elements characterized earlier as tumor associated macrophages. (
  • In this work, immunohistochemical studies identified extravascular fibrin deposits within white adipose tissue and liver as distinct features of mice fed a high-fat diet (HFD) as well as obese patients. (
  • This is to be expected from a fibrinolytics because past fibrin deposits block the penetration rate. (
  • Treatment with the antibody put a damper on this fibrin-driven oxidative mechanism, which may contribute to many different neurodegenerative diseases. (
  • However, the opposite was found when cells were grown over fibrin: 6 × 10 −6 ng/mL per cell without RGD vs. 17 × 10 −6 ng/mL per cell with RGD. (
  • The fibrin meshwork structure is characterized by fibrin thickness, fiber density, pores size, and rigidity that reflects fibrin FXIIIa cross-linking and clot structure [ 11 ]. (