Technical Indicators to Evaluate the Degree of Large Clot Formation Inside the Membrane Fiber Bundle of an Oxygenator in an In Vitro Setup

2018 ◽  
Vol 43 (2) ◽  
pp. 159-166 ◽  
Author(s):  
Andreas Kaesler ◽  
Felix Hesselmann ◽  
Mark O. Zander ◽  
Peter C. Schlanstein ◽  
Georg Wagner ◽  
...  
Keyword(s):  
Fiber Bundle ◽  
Clot Formation ◽  
Technical Indicators ◽  
Large Clot

The Haemocompatibility of Biomaterials In Vitro: Investigations on the Mechanism of the Whole-blood Clot Formation Test

1992 ◽  
Vol 20 (3) ◽  
pp. 390-395 ◽  
Author(s):  
Thomas Groth ◽  
Katrin Derdau ◽  
Frank Strietzel ◽  
Frank Foerster ◽  
Hartmut Wolf
Keyword(s):  
Whole Blood ◽  
Blood Clotting ◽  
Blood Clot ◽  
Formation Rate ◽  
Clot Formation ◽  
Coagulation Cascade ◽  
Contact Activation ◽  
Human Fibrinogen ◽  
Static Conditions

Twenty years ago Imai & Nose introduced a whole-blood clotting test for the estimation of haemocompatibility of biomaterials in vitro In our paper a modification of this assay is described and the mechanism of clot formation further elucidated. It was found that neither the inhibition of platelet function nor the removal of platelets from blood significantly changed the clot formation rate on glass and polyvinyl chloride in comparison to the rate tor whole blood. Scanning electron microscopy demonstrated that platelets were not involved in clot formation near the blood/biomaterial interface. Thus, it was concluded that the system of contact activation of the coagulation cascade dominates during clot formation under static conditions. The latter conclusion was supported by the fact that preadsorption of human serum albumin or human fibrinogen onto the glass plates used, decreased the clot formation rate in the same manner.

scholarly journals Repeated social defeat exaggerates fibrin-rich clot formation in FeCl3-induced arterial thrombosis mouse model by enhancing NETs formation via modulation of neutrophil functional properties

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Sugimoto ◽  
H Yamada ◽  
H Kubota ◽  
D Miyawaki ◽  
M Saburi ◽  
...  
Keyword(s):  
Functional Properties ◽  
Arterial Thrombosis ◽  
Social Defeat ◽  
Arterial Injury ◽  
Physical Contact ◽  
Clot Formation ◽  
Positive Staining ◽  
Double Positive ◽  
The Impact

Abstract Background and objective Depression is an independent risk factor of cardiovascular disease (CVD). We have recently shown that repeated social defeat (RSD) precipitates depressive-like behaviors in apoE−/− mice and exaggerates atherosclerosis development by enhancing neutrophil extracellular traps (NETs) formation. Here, we investigated the impact of RSD on arterial thrombosis. Methods and results Eight-week-old male WT mice were exposed to RSD by housing with a larger CD-1 mouse in a shared home cage. They were subjected to vigorous physical contact daily for 10 consecutive days. Control mice were housed in the same gage without physical contact. After social interaction test to confirm depressive-like behaviors, defeated mice (19 of 31) and control mice (12 of 14) were underwent arterial injury at 10 wks of age. A filter paper saturated with 10% FeCl3 was applied on the adventitial surface of left carotid artery for 3 min and analyzed 3 hrs later. The volume of thrombi was comparable between the two groups. However, fibrinogen/fibrin-positive areas in immunofluorescent images significantly increased in defeated mice (27.8% vs. 48.8%, p<0.01). The number of Ly-6G-positive cells in thrombi was markedly higher in defeated mice (144/mm2 vs. 878/mm2, p<0.05). Further, Ly-6G-positive cells were almost accumulated at the inner surface of injured artery, which were co-localized with neutrophil elastase, Cit-H3, and CD41-positive staining. Treatment with DNase I completely diminished the exaggerated fibrin-rich clot formation in defeated mice to an extent similar to that in control mice (25.7% vs. 22.3%, p = ns), without affecting the volume of thrombi and accumulation of Ly-6G-positive cells. Given that platelet aggregations induced by ADP or collagen were comparable between the two groups, neutrophil functional properties primarily contribute to the exaggerated fibrin-rich clot formation in defeated mice. We then examined neutrophil subset and vulnerability to NETs formation. At 3 hrs after FeCl3 application, the numbers of immature neutrophils (Ly6Glo/+CXCR2-) were comparable between the two groups in both bone marrow (BM) and peripheral blood (PB). In contrast, the number of PB mature neutrophils (Ly6G+CXCR2+) was markedly higher in defeated mice than control mice (580±68 /μl vs. 1265±114, p<0.01). We next examined in vitro NETs formation upon PMA in BM mature neutrophils by FACS and nucleic acid staining. The percentage of double-positive cells (Cit-H3, MPO) was significantly higher in defeated mice (7.5% vs. 10.2%, p<0.05), as well as SYTOX green-positive cells expelling DNA fibers (8.1% vs. 11.8%, p<0.05). Conclusions Our findings demonstrate for the first time that repeated social defeat enhances fibrin-rich clot formation after arterial injury by enhancing NETs formation via modulation of neutrophil functional properties, suggesting that NETosis could be a new therapeutic target in depression-related CVD development. Funding Acknowledgement Type of funding source: None

scholarly journals Alpha-ketoglutarate augments prolyl hydroxylase-2 mediated inactivation of phosphorylated-Akt to inhibit induced-thrombosis and inflammation

2021 ◽  
Author(s):  
Nishith M Shrimali ◽  
Sakshi Agarwal ◽  
Simrandeep Kaur ◽  
Sulagna Bhattacharya ◽  
Sankar Bhattacharyya ◽  
...  
Keyword(s):  
Viral Load ◽  
Prolyl Hydroxylase ◽  
Cytokine Secretion ◽  
Clot Formation ◽  
Rescue Effect ◽  
Leukocyte Accumulation ◽  
Phosphorylated Akt

Phosphorylation of Akt (pAkt) regulates multiple physiological and pathological processes including thrombosis and inflammation. In an approach to inhibit the pathological signalling of pAkt by prolyl-hydroxylase-2 (PHD2) we employed alpha-ketoglutarate (AKG), a cofactor of PHD2. Octyl-AKG supplementation to platelets promoted PHD2 activity through elevated intracellular AKG:succinate ratio and reduced aggregation in vitro by suppressing pAkt1(Thr308). Augmented PHD2 activity was confirmed by increased hydroxylated-proline alongside enhanced binding of PHD2 to pAkt in AKG-treated platelets. Contrastingly, inhibitors of PHD2 significantly increased pAkt1 in platelets. Octyl-AKG followed similar mechanism in monocytes to inhibit cytokine secretion in vitro. Our data also describe a suppressed pAkt1 and reduced activation of platelet and leukocyte obtained from mice supplemented with dietary-AKG, unaccompanied by alteration in their counts. Dietary-AKG significantly reduced clot formation and leukocyte accumulation in various organs including lung of mice treated with thrombosis-inducing agent carrageenan. Importantly, we observed a significant rescue effect of dietary-AKG on inflamed lung of SARS-CoV-2 infected hamsters. AKG significantly reduced leukocyte accumulation, clot formation and viral load alongside downmodulation of pAkt in lung of the infected animals. Therefore, our study suggests a safe implementation of dietary-AKG in prevention of Akt-driven anomalies including thrombosis and inflammation, highlighting a better pulmonary management in COVID-19.

Abstract 356: Adhesion of Staphylococcus Epidermidis to Fibrinogen Alters Clot Formation Kinetics and Ultimate Stiffness

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Carolyn Vitale ◽  
Tianhui Ma ◽  
Michael J Solomon ◽  
J. Scott VanEpps
Keyword(s):  
Stationary Phase ◽  
Deposition Rate ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Fibrin Clot ◽  
Exponential Phase ◽  
Automated Image Analysis ◽  
Clot Formation ◽  
Coagulation Proteins

Bacterial infection is known to increase the risk for thromboembolism. The mechanism underlying this correlation remains largely unknown. We recently showed that the common pathogen Staphylococcus epidermidis retards clot formation, increases clot elasticity and generates a heterogeneous clot structure that remodels over time. Here, we elucidate the mechanism of this process by evaluating the capacity for S. epidermidis to bind to fibrinogen as a function of its growth phase. We hypothesized that the effect of S. epidermidis on a fibrin clot is related to its propensity toward biofilm formation. Therefore, stationary phase (biofilm-like) S. epidermidis will have a more robust effect on clot kinetics and elasticity than exponential phase (planktonic). Furthermore, this difference is mediated by increased adhesion to fibrinogen. Rheometry was used to evaluate the formation and resultant elasticity of fibrin clots with exponential or stationary phase S. epidermidis . A functional in vitro model was developed to evaluate adhesion of S. epidermidis to a fibrinogen coated surface in a continuously flowing environment. Fluorescent labeled exponential and stationary phase S. epidermidis were visualized flowing through a parallel plate microfluidic chamber past immobilized fibrinogen. Images were obtained every 3 seconds for 30 min. Bacterial deposition rate and mean adhesion time were quantified by automated image analysis. A paired Student’s t-test was used for statistical analysis. Stationary phase S. epidermidis retards clot formation and increases resultant elasticity while exponential phase only slightly reduces elasticity. The bacterial deposition rate onto fibrinogen was significantly (p=0.03) greater for stationary phase (1741 ± 1513 cells/cm 2 · sec -1 ) vs exponential phase (676 ± 270 cells/cm 2 · sec -1 ). The average adhesion time however was similar for exponential and stationary phase cells. Coagulation proteins can provide a framework for bacterial adhesion, biofilm formation and infection. In turn infected thrombi with (biofilm-like) bacteria are stiffer which correlates to more frequent bacterial binding to fibrinogen. This provides a potential molecular mechanism for infection mediated thromboembolic events.

scholarly journals Thrombin generation and fibrin clot formation under hypothermic conditions: An in vitro evaluation of tissue factor initiated whole blood coagulation

2014 ◽  
Vol 29 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Matthew F. Whelihan ◽  
Armin Kiankhooy ◽  
Kathleen E. Brummel-Ziedins
Keyword(s):  
Tissue Factor ◽  
Blood Coagulation ◽  
Whole Blood ◽  
Thrombin Generation ◽  
Fibrin Clot ◽  
Clot Formation ◽  
In Vitro Evaluation

Effect of Progesterone and Synthetic Progestins on Whole Blood Clot Formation and Erythrocyte Structure

2017 ◽  
Vol 23 (3) ◽  
pp. 607-617 ◽  
Author(s):  
Albe C. Swanepoel ◽  
Odette Emmerson ◽  
Etheresia Pretorius
Keyword(s):  
Whole Blood ◽  
Blood Clot ◽  
Thrombotic Event ◽  
Clot Formation ◽  
Erythrocyte Aggregation ◽  
Erythrocyte Morphology ◽  
Increased Risk ◽  
Blood Clots ◽  
Membrane Ultrastructure

AbstractCombined oral contraceptive (COC) use is a risk factor for venous thrombosis (VT) and related to the specific type of progestin used. VT is accompanied by inflammation and pathophysiological clot formation, that includes aberrant erythrocytes and fibrin(ogen) interactions. In this paper, we aim to determine the influence of progesterone and different synthetic progestins found in COCs on the viscoelasticity of whole blood clots, as well as erythrocyte morphology and membrane ultrastructure, in an in vitro laboratory study. Thromboelastography (TEG), light microscopy, and scanning electron microscopy were our chosen methods. Our results point out that progestins influence the rate of whole blood clot formation. Alterations to erythrocyte morphology and membrane ultrastructure suggest the presence of eryptosis. We also note increased rouleaux formation, erythrocyte aggregation, and spontaneous fibrin formation in whole blood which may explain the increased risk of VT associated with COC use. Although not all COC users will experience a thrombotic event, individuals with a thrombotic predisposition, due to inflammatory or hematological illness, should be closely monitored to prevent pathological thrombosis.

Role of factor XIII in fibrin clot formation and effects of genetic polymorphisms

Blood ◽  
2002 ◽  
Vol 100 (3) ◽  
pp. 743-754 ◽  
Author(s):  
Robert A. S. Ariëns ◽  
Thung-Shenq Lai ◽  
John W. Weisel ◽  
Charles S. Greenberg ◽  
Peter J. Grant
Keyword(s):  
Genetic Polymorphisms ◽  
Factor Xiii ◽  
Blood Clot ◽  
Site Directed Mutagenesis ◽  
Clot Formation ◽  
Factor Xiiia ◽  
Clotting Factors ◽  
Functional Features

Abstract Factor XIII and fibrinogen are unusual among clotting factors in that neither is a serine protease. Fibrin is the main protein constituent of the blood clot, which is stabilized by factor XIIIa through an amide or isopeptide bond that ligates adjacent fibrin monomers. Many of the structural and functional features of factor XIII and fibrin(ogen) have been elucidated by protein and gene analysis, site-directed mutagenesis, and x-ray crystallography. However, some of the molecular aspects involved in the complex processes of insoluble fibrin formation in vivo and in vitro remain unresolved. The findings of a relationship between fibrinogen, factor XIII, and cardiovascular or other thrombotic disorders have focused much attention on these 2 proteins. Of particular interest are associations between common variations in the genes of factor XIII and altered risk profiles for thrombosis. Although there is much debate regarding these observations, the implications for our understanding of clot formation and therapeutic intervention may be of major importance. In this review, we have summarized recent findings on the structure and function of factor XIII. This is followed by a review of the effects of genetic polymorphisms on protein structure/function and their relationship to disease.

The In Vitro Effects of Fibrinogen Concentrate, Factor XIII and Fresh Frozen Plasma on Impaired Clot Formation After 60% Dilution

2008 ◽  
Vol 106 (5) ◽  
pp. 1360-1365 ◽  
Author(s):  
Thorsten Haas ◽  
Dietmar Fries ◽  
Corinna Velik-Salchner ◽  
Christian Reif ◽  
Anton Klingler ◽  
...  
Keyword(s):  
Factor Xiii ◽  
Fresh Frozen Plasma ◽  
Clot Formation ◽  
Fibrinogen Concentrate ◽  
Fresh Frozen ◽  
In Vitro Effects ◽  
Frozen Plasma

In Vitro Inhibition of Factor XIII Retards Clot Formation, Reduces Clot Firmness, and Increases Fibrinolytic Effects in Whole Blood

2009 ◽  
Vol 109 (4) ◽  
pp. 1023-1028 ◽  
Author(s):  
Csilla Jámbor ◽  
Viviane Reul ◽  
Thomas W. Schnider ◽  
Priska Degiacomi ◽  
Hubert Metzner ◽  
...  
Keyword(s):  
Whole Blood ◽  
Factor Xiii ◽  
Clot Formation ◽  
In Vitro Inhibition
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