scholarly journals A novel missense mutation in the FGB g. 3354 T>A (p. Y41N), Fibrinogen Caracas VIII

2011 ◽  
Vol 105 (04) ◽  
pp. 627-634 ◽  
Author(s):  
Héctor Rojas ◽  
Michael Meyer ◽  
Oscar Castillo ◽  
Arlette De Sáez Ruiz ◽  
John Weisel ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Fibrin Clot ◽  
Polymerization Process ◽  
Confocal Laser ◽  
Fibrinogen Concentration ◽  
Thrombin Time ◽  
Normal Range ◽  
Amino Terminal ◽  
Fibrin Network ◽  
Β Chain

SummaryA novel dysfibrinogenaemia with a replacement of Tyr by Asn at Bβ41 has been discovered (fibrinogen Caracas VIII). An asymptomatic 39-year-old male was diagnosed as having dysfibrinogenaemia due to a mildly prolonged thrombin time (+ 5.8 seconds); his fibrinogen concentration was in the low normal range, both by Clauss and gravimetric determination, 1.9 g/l and 2.1 g/l, respectively. The plasma polymerization process was slightly impaired, characterised by a mildly prolonged lag time and a slightly increased final turbidity. Permeation through the patients´ clots was dramatically increased, with the Darcy constant around four times greater than that of the control (22 ± 2 x10–9 cm2 compared to 6 ± 0.5 x10–9 cm2 in controls). The plasma fibrin structure of the patient, by scanning electron microscopy, featured a mesh composed of thick fibres (148 ± 50 nm vs. 120 ± 31 nm in controls, p<0.05) and larger pores than those of the control fibrin clot. The viscoelastic properties of the clot from the patient were also altered, as the storage modulus (G‘, 310 ± 30) was much lower than in the control (831 ± 111) (p ≤0.005). The interaction of the fibrin clot with a monolayer of human microvascular endothelial cells, by confocal laser microscopy, revealed that the patients´ fibrin network had less interaction with the cells. These results demonstrate the significance of the amino terminal end of the β chain of fibrin in the polymerisation process and its consequences on the clot organisation on the surface of endothelial cells.

Haemostatic changes related to fibrin formation and fibrinolysis during the first trimester in normal pregnancy and in recurrent miscarriage

2007 ◽  
Vol 97 (04) ◽  
pp. 552-557 ◽  
Author(s):  
Ysabel Ramirez ◽  
Chandrasekaran Nagaswami ◽  
Leona Masova ◽  
Anibal Pulido ◽  
José Mora ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Recurrent Miscarriage ◽  
First Trimester ◽  
Normal Pregnancy ◽  
Polymerization Process ◽  
Control Group ◽  
Fibrinogen Concentration ◽  
Fibrin Network ◽  
History Of ◽  
Pregnant State

SummaryWe have studied some biophysical properties of the fibrin network during the normal state of pregnancy and in patients with recurrent miscarriage (RM), in the first trimester of pregnancy. The fibrin polymerization process, followed by turbidity, showed that the rate of fibrin monomer assembly and the final turbidity was increased in the pregnant group (normal and with history of RM) compared to non-pregnant women (normal and RM), which is consistent with the increased fibrinogen concentration during pregancy. No changes were observed in the Darcy constant (Ks) of RM clots, pregnant or not; however, in pregnant control subjects the Ks increased (p=0.03).The fibrin lysis rate was increased in pregnant women compared to non-pregnant, being faster in women with RM. The rheological properties of the fibrin network in the non-pregnant group (control and RM patients) were similar; in the pregnant state, the fibrin network of the control group was 1.3 times stiffer compared to the control non-pregnant women, and almost unchanged in RM patients. In this study we have found changes in the clot structure that seem to be related to normal pregnancy and an increased rate of the fibrin lysis process in the RM patients, which may have clinical relevance.

EFFECTS OF NICKEL CHLORIDE ON INDICES OF HEMOCOAGULATION AND LIPID PEROXIDATION IN RATS

2019 ◽  
pp. 83-90
Author(s):  
Э.М. Гаглоева ◽  
В.Б. Брин ◽  
С.В. Скупневский ◽  
Н.В. Боциева ◽  
Т.В. Молдован
Keyword(s):  
Lipid Peroxidation ◽  
Antioxidant Enzymes ◽  
Platelet Aggregation ◽  
Prothrombin Time ◽  
Partial Thromboplastin Time ◽  
Nickel Chloride ◽  
Activated Partial Thromboplastin Time ◽  
Fibrinogen Concentration ◽  
Thrombin Time ◽  
Hemostasis System

Цель исследования - изучить состояние системы гемостаза при хронической интоксикации хлоридом никеля, исследовать взаимосвязь показателей гемокоагуляции с процессами липопероксидации у крыс в эксперименте. Методика. Опыты проводили на крысах-самцах Вистар (n=50, 230-250 г). Раствор NiCl2 (5 мг/кг) вводили внутрижелудочно ежедневно в течение 2 нед, 1 и 2 мес. По завершении эксперимента исследовали состояние тромбоцитарного и коагуляционного звеньев гемостаза, антикоагулянтную и фибринолитическую активность крови, а также определяли активность процессов перекисного окисления липидов и антиоксидантных ферментов. Результаты. Установлено, что через 2 нед и 1 мес интоксикации у крыс отмечались гиперкоагуляционные изменения показателей свертывающей системы крови: повышение агрегационной активности тромбоцитов, увеличение концентрации фибриногена, снижение активированного частичного тромбопластинового времени (АЧТВ) и протромбинового времени. В этот период регистрировалось увеличение антитромбиновой и фибринолитической активности крови. Через 2 мес наблюдалось подавление активности клеточного звена гемостаза - тромбоцитопения, ослабление степени АДФ-индуцируемой агрегации тромбоцитов. Выявлялась тенденция к уменьшению концентрации фибриногена. На фоне снижения АЧТВ и тромбинового времени отмечалось увеличение протромбинового времени. В то же время регистрировалось угнетение противосвертывающего звена системы гемостаза (снижалась активность антитромбина III), наблюдалось истощение резервных возможностей фибринолитического звена (замедление фXIIа-зависимого эуглобулинового лизиса) и увеличение содержания растворимых фибрин мономерных комплексов, что свидетельствует о наличии тромбинемии. Через 2 нед, один и два месяца интоксикации у животных выявлялись корреляционные связи между основными показателями системы гемостаза и активностью процессов перекисного окисления липидов и антиоксидантных ферментов. Заключение. Полученные данные подтверждают наличие взаимосвязи активности процессов липопероксидации и системы гемостаза, в том числе при хронической никелевой интоксикации. Результаты исследования позволяют рекомендовать применение антиоксидантов для разработки способов коррекции гемостатических сдвигов при воздействии на организм тяжелых металлов. The aim. To study the state of the hemostasis system in chronic nickel intoxication and to investigate the relationship between hemocoagulation indices and lipoperoxidation processes in rats. Methods. Experiments were carried out on male Wistar rats (n=50, 230-250 g). A solution of nickel chloride (5 mg/kg) was administered daily intragastrically for two weeks, one and two months. At the end of the experiments, indices of platelet and coagulation hemostasis systems, anticoagulant and fibrinolytic activity of blood plasma, and activities of lipid peroxidation and antioxidant enzymes were studied. Results. Hypercoagulative changes in indices of the coagulation system were observed in rats after two weeks and one month of intoxication, including increased platelet aggregation and fibrinogen concentration and shortened activated partial thromboplastin time and prothrombin time. During the same period, increased antithrombin and fibrinolytic activities were observed. The depressed activity of the cellular component of hemostasis evident as thrombocytopenia and impaired ADP-induced platelet aggregation was detected after two months of intoxication. A tendency to decrease in fibrinogen concentration was observed. The shortened activated partial thromboplastin time and thrombin time were associated with prolonged prothrombin time. At the same time, inhibition of the anticoagulant component of hemostasis (decreased antithrombin III activity), exhaustion of the fibrinolysis system reserve (delayed fXIIa-dependent euglobulin lysis), and a significant increase in soluble fibrin monomeric complexes indicative of thrombinemia were observed. After two weeks, one and two months of nickel intoxication, a correlation was found between the major indices of the hemostasis system and the activities of lipid peroxidation and antioxidant enzymes. Conclusion. The study confirmed a relationship between the lipid peroxidation activity and the hemostasis system, specifically in chronic nickel intoxication. This result allows to recommend the use of antioxidants in developing methods for correction of hemostatic induced affected by heavy metals.

scholarly journals Selective inhibition of amino-terminal methionine processing by TNP-470 and ovalicin in endothelial cells

1999 ◽  
Vol 6 (11) ◽  
pp. 823-833 ◽  
Author(s):  
Benjamin E Turk ◽  
Eric C Griffith ◽  
Susan Wolf ◽  
Klaus Biemann ◽  
Yie-Hwa Chang ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Selective Inhibition ◽  
Amino Terminal

Effect of glycocalyx on shear-dependent albumin uptake in endothelial cells

2004 ◽  
Vol 287 (5) ◽  
pp. H2287-H2294 ◽  
Author(s):  
Akinori Ueda ◽  
Manabu Shimomura ◽  
Mariko Ikeda ◽  
Ryuhei Yamaguchi ◽  
Kazuo Tanishita
Keyword(s):  
Endothelial Cells ◽  
Shear Stress ◽  
Laser Scanning ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Interface Barrier ◽  
Uptake Process ◽  
Static Conditions

The glycocalyx layer on the surface of an endothelial cell is an interface barrier for uptake of macromolecules, such as low-density lipoprotein and albumin, in the cell. The shear-dependent uptake of macromolecules thus might govern the function of the glycocalyx layer. We therefore studied the effect of glycocalyx on the shear-dependent uptake of macromolecules into endothelial cells. Bovine aorta endothelial cells were exposed to shear stress stimulus ranging from 0.5 to 3.0 Pa for 48 h. The albumin uptake into the cells was then measured using confocal laser scanning microscopy, and the microstructure of glycocalyx was observed using electron microscopy. Compared with the uptake into endothelial cells under static conditions (no shear stress stimulus), the albumin uptake at a shear stress of 1.0 Pa increased by 16% and at 3.0 Pa decreased by 27%. Compared with static conditions, the thickness of the glycocalyx layer increased by 70% and the glycocalyx charge increased by 80% at a shear stress of 3.0 Pa. The albumin uptake at a shear stress of 3.0 Pa for cells with a neutralized (no charge) glycocalyx layer was almost twice that of cells with charged layer. These findings indicate that glycocalyx influences the albumin uptake at higher shear stress and that glycocalyx properties (thickness and charge level) are involved with the shear-dependent albumin uptake process.

Experimental rationale for using a viscoprotection of the corneal endothelium on the graft formed with a femtosecond laser for the descemet stripping endothelial keratoplasty

2021 ◽  
pp. 94-96
Author(s):  
I.S. Tkachenko ◽  
◽  
B.E. Malyugin ◽  
S.A. Borzenok ◽  
D.S. Ostrovskiy ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Femtosecond Laser ◽  
Corneal Endothelium ◽  
Hydroxypropyl Methylcellulose ◽  
Lamellar Keratoplasty ◽  
Confocal Laser ◽  
Control Group ◽  
Endothelial Keratoplasty ◽  
Descemet Stripping Endothelial Keratoplasty ◽  
Experimental Group

Purpose. To rationale experimentally the use of a viscoprotection of the corneal endothelium on the graft formed with a femtosecond laser for the descemet stripping endothelial keratoplasty. Material and methods. In our study, we used 12 pig's corneoscleral discs. The preservation time before the experiment averaged 12±4 hours. The corneas were divided into 2 groups. In the operating room, the graft was formed using an LDV Z8 femtosecond laser (Ziemer, Switzerland) from the endothelial side. Before applanation of the donor cornea and femtolaser head, a 1% solution of hydroxypropyl methylcellulose (HPMC) was applied to the endothelium - experimental group. The control group was appraised according to the standard technique, with the application of a few drops of a solution for storing the corneas. Then the applanation was monitored and evaluated by laser optical coherence tomography. Then the graft was separated from the bed and transferred to a conservation medium. Under laboratory conditions, to determine the viability of endothelial cells, the graft was stained with a «vital» dye with the commercial name Life and Dead (Abcam, UK) and placed in a confocal laser scanning microscope. Endothelial cells were counted using the ImageJ software. Results. In the experimental and control groups, the number of living endothelial cells (EC) was 91.06±1.49% and 83.86±2.14%, respectively (p<0.001). The number of dead ECs in the control group was 7.2±0.65% more than in the experimental group and amounted to 16.14±2.14% and 8.94±1.49%, respectively (p<0.001). Conclusion. The study demonstrated that the use of viscoprotection of the corneal graft endothelium for posterior lamellar keratoplasty is quite effective, and significantly reduces the loss of EC at the stage of cutting out the graft with a femtosecond laser. Key words: descemet stripping endothelial keratoplasty, femtosecond laser, vital dyes.

Fibrinogen C-terminal peptidic sequences (Haptides) modulate fibrin polymerization

2004 ◽  
Vol 91 (01) ◽  
pp. 43-51 ◽  
Author(s):  
Matti Ben-Moshe ◽  
Sholomo Magdassi ◽  
Raphael Gorodetsky ◽  
Gerard Marx
Keyword(s):  
Platelet Aggregation ◽  
Cell Attachment ◽  
Fibrin Clot ◽  
Nano Particles ◽  
Amino Acid Residues ◽  
Fibrin Gel ◽  
Transmission Microscopy ◽  
Average Size ◽  
Β Chain ◽  
Positively Charged

SummaryWe previously described synthetic peptides of 19-21 amino acid residues, homologous to the C-termini of fibrinogen Fib340 and Fib420, from the β-chain (Cβ), the extended αE chain (CαE) and near the end of the γ-chain (preCγ) which elicited attachment (haptotactic) responses from mesenchymal cells. We named these haptotactic peptides -Haptides. The effects of Haptides on fibrin clot formation was evaluated and their possible effects on platelet aggregation was examined. The Haptides Cβ, CαE and preCγ, (2-10 μM) increased fibrin clot turbidity and also decreased thrombin-induced clotting time. Higher concentrations (>120 μM of Cβ or preCγ) induced fibrinogen precipitation even without thrombin. These precipitates exhibited different ultrastructure from thrombin-induced fibrin by scanning and transmission microscopy. C-terminal peptides of the other fibrinogen chains exerted no such effects. Sepharose beads covalently coated with either whole fibrinogen or Haptides (SB-Fib or SB-Haptide) highly adsorbed free FITCHaptides. In aqueous solution, Haptides formed nano-particles with average size of ∼150nm in diameter. We suggest that such positively charged aggregates could serve to nucleate and accelerate fibrin gel formation. These results also indicate that Cβ and preCγ sequences within fibrin(ogen) participate in the docking and condensation of fibrin(ogen) during its assembly into a fibrin clot. By contrast, Haptides up to 100µM did not bind to platelets, and had no effect on platelet aggregation. Our findings highlight the roles of the C-terminal sequences of the β and γ chains in fibrin(ogen) polymerization as well as in cell attachment.

DIRECTED MUTAGENESIS OF HUMAN FIBRINOGEN: Aα CHAIN SUBSTITUTIONS THAT ALTER THROMBIN CLEAVAGE AND ANTIBODY RECOGNITION

1987 ◽  
Author(s):  
S T Lord
Keyword(s):  
Amino Acids ◽  
Blot Analysis ◽  
Fibrin Clot ◽  
Fibrinopeptide A ◽  
Human Fibrinogen ◽  
Antibody Recognition ◽  
Amino Terminal ◽  
Thrombin Cleavage ◽  
Initial Event ◽  
Bacterial Lysates

The initial event in fibrin clot formation is the thrombin catalized cleavage of the Aa chain of fibrinogen between Argl6 and Glyl7, releasing fibrinopeptide A. Previous data indicate that most of the information required for thrombin recognition and cleavage of the Aa chain lies within the amino terminal 51 residue CNBr fragment. In order to use protein engineering techniques to study the interaction of thrombin with the Aa chain, we have constructed a plasmid expression vector which encodes a tripartite protein consisting of amino acids 1-50 of the Aa chain of human fibrinogen followed by 60 amino acids of chicken collagen, and the beta-galactosidase protein from Escherichia coli. The codons for an initiator methionine and amino acids 1-50 were assembled from 7 oligonucleotides. Protein blot analysis of bacterial lysates of cells induced to synthesize this tribrid protein show a single band (MW = 125,000) crossreactive with a monoclonal antibody, Y-18, which recognizes the Aa chain of fibrinogen but not the products of thrombin cleavage. When these lysates are incubated with thrombin, fibrinopeptide A is released as demonstrated both by protein blot analysis and radioimmunoassay. By including one heterogeneous oligonucleotide in the assembly process, we have constructed plasmids which encode specific amino acid substitutions within residues 1-23. One of these substitutions, Glyl4 to val, significantly alters both cleavage by thrombin and recognition by Y-18. Substitution of ilu for Arg23 alters neither thrombin cleavage nor monoclonal recognition while substitution of leu for Argl6 alters thrombin cleavage, but not recognition by Y-18.

scholarly journals Brief Report: Plasma Activity of Antihemophilic Globulin (AHG) and Other Coagulation Factors in Swiss Type of Agammaglobulinemia

Blood ◽  
1969 ◽  
Vol 34 (5) ◽  
pp. 701-705 ◽  
Author(s):  
HAROLD M. MAURER ◽  
ORESTES VALDES ◽  
CLARE N. SHUMWAY ◽  
F. STANFORD MASSIE
Keyword(s):  
Factor Viii ◽  
Plasma Cell ◽  
Chronic Infection ◽  
Coagulation Factors ◽  
Reticuloendothelial System ◽  
Fibrinogen Concentration ◽  
Normal Range ◽  
And Storage ◽  
Plasma Activity

Abstract Although the site of synthesis and storage of antihemophilic globulin (AHG, Factor VIII) is unknown, available evidence suggests that these processes occur in the reticuloendothelial system. We studied the plasma activity of AHG and other coagulation factors in a patient with Swiss type of agammaglobulinemia. Except for increased fibrinogen concentration probably related to chronic infection, the activity of all coagulation factors including AHG was within the normal range. These studies suggest that the lymphocyte and plasma cell are unlikely sites of AHG synthesis or storage.

Influence Of Elastase On Blood Coagulation Factors: Studies In Vitro, In Rats And In Göttinger Miniatur Pigs

1981 ◽  
Author(s):  
U Kasten ◽  
U Artmann ◽  
T Kaethner ◽  
H Burchardi ◽  
H Köstering
Keyword(s):  
Blood Coagulation ◽  
Coagulation Factors ◽  
Bleeding Complications ◽  
Thrombin Time ◽  
Normal Range ◽  
Blood Coagulation Factors ◽  
Acute Respiratory Insufficiency ◽  
Coagulation Tests ◽  
Antifibrinolytic Drugs

The influence of blood coagulation factors in pat. with acute respiratory insufficiency of adults, especially of the so called “pancreatitis lungs” is still unknown. In order to find out the effect of elastase, possibly activated by trypsin in pat. with acute pancreatitis, on blood coagulation factors, we performed some studies. In vitro elastase induces in plasma and blood in correlation to the dosages Enhancement of thrombingeneration in the TGT, a shortening of PTT, Thrombin time and of r- and k-time in the TEG, a loss of fibrinogen and an increase of fibrinmono-mercomplexes. In another study, elastase (960 U/ kg b.w.) was injected intravenously in rats. 30 min. later there was found a loss of fibrinogen, number of platelets, Prothrombin and a prolongation of PTT and Thrombin time and an increase of fibrinomonomercomplexes, especially in these rats, which received beside elastase Kalikreininhibitors or antifibrinolytic drugs. After repeated injections (3 times within 30 h) we found histomorpholgically thrombi as well as bleeding complications. In another study we performed (150 min) an infusion of elastase (333 U/kg b.w./h) to 9 pigs. We determined a loss of fibrinogen of platelets, of F. II, F. VII and F. XIII, a prolongation of PTT. F. VIII and F. V remained within the normal range But there was found an enhancement of Thrombin generation in the TGT, too. Compariening the results of blood coagulation tests and of histomorphological findings, elastase induced a DIC. We have to discuss their influence on ARIA and “Pancreatic lungs”.

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