A thromboelastography study on the in vitro effects of L-arginine and L-NG-nitro arginine methyl ester on human whole blood coagulation and fibrinolysis

1996 ◽  
Vol 7 (7) ◽  
pp. 678-683 ◽  
Author(s):  
Y. M. Dambisya ◽  
T-L. Lee
Keyword(s):  
Methyl Ester ◽  
Blood Coagulation ◽  
Whole Blood ◽  
Human Whole Blood ◽  
In Vitro Effects ◽  
Coagulation And Fibrinolysis

scholarly journals Glycocalyx components affect platelet function, whole blood coagulation, and fibrinolysis: an in vitro study suggesting a link to trauma-induced coagulopathy

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Martin W. Britten ◽  
Laura Lümers ◽  
Kenji Tominaga ◽  
Jürgen Peters ◽  
Daniel Dirkmann
Keyword(s):  
Platelet Aggregation ◽  
Heparan Sulfate ◽  
Chondroitin Sulfate ◽  
Blood Coagulation ◽  
Platelet Function ◽  
Whole Blood ◽  
Dependent Manner ◽  
Trauma Induced Coagulopathy ◽  
Coagulation And Fibrinolysis

Abstract Background The mechanisms of trauma induced coagulopathy (TIC) are considered multifactorial. Amongst others, however, shedding of the endothelial glycocalyx resulting in increased concentrations of glycocalyx fragments in plasma might also play a role. Thus, we hypothesized that shedded glycocalyx components affect coagulation and may act as humoral mediators of TIC. Methods To investigate effects of heparan sulfate, chondroitin sulfate, syndecan-1, versican, and thrombomodulin we added these fragments to in vitro assays of whole blood from healthy volunteers to yield concentrations observed in trauma patients. Platelet function, whole blood coagulation, and fibrinolysis were measured by standard coagulation tests, impedance aggregometry (IA), and viscoelastic tests (VET). To assess dose-response relationships, we performed IA with increasing concentrations of versican and VET with increasing concentrations of thrombomodulin. Results Intrinsically activated clotting times (i.e., activated partial thromboplastin time and intrinsically activated VET with and without heparinase) were unaffected by any glycocalyx fragment. Thrombomodulin, however, significantly and dose-dependently diminished fibrinolysis as assessed by VET with exogenously added rt-PA, and increased rt-PA-induced lysis Indices after 30 (up to 108% of control, p <  0,0001), 45 (up to 368% of control, p <  0,0001), and 60 min (up to 950% of control, p <  0,0001) in VET. Versican impaired platelet aggregation in response to arachidonic acid (up to − 37,6%, p <  0,0001), ADP (up to − 14,5%, p <  0,0001), and collagen (up to − 31,8%, p <  0,0001) in a dose-dependent manner, but did not affect TRAP-6 induced platelet aggregation. Clotting time in extrinsically activated VET was shortened by heparan sulfate (− 7,2%, p = 0,024), chondroitin sulfate (− 11,6%, p = 0,016), versican (− 13%, p = 0,012%), and when combined (− 7,2%, p = 0,007). Conclusions Glycocalyx components exert distinct inhibitory effects on platelet function, coagulation, and fibrinolysis. These data do not support a ‘heparin-like auto-anticoagulation’ by shed glycosaminoglycans but suggest a possible role of versican in trauma-induced thrombocytopathy and of thrombomodulin in trauma-associated impairment of endogenous fibrinolysis.

scholarly journals AB0095 PRECLINICAL CHARACTERIZATION OF CJ-15314, A HIGHLY SELECTIVE JAK1 INHIBITOR, FOR THE TREATMENT OF AUTOIMMUNE DISEASES

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1347.2-1347
Author(s):  
S. Y. Ki ◽  
H. Shin ◽  
Y. Lee ◽  
H. R. Bak ◽  
H. Yu ◽  
...  
Keyword(s):  
Autoimmune Disease ◽  
Autoimmune Diseases ◽  
Whole Blood ◽  
Inflammatory Diseases ◽  
Selective Inhibition ◽  
Janus Kinase ◽  
Dependent Manner ◽  
Human Whole Blood

Background:Janus kinases (JAK1, JAK2, JAK3, and TYK2) play critical roles in mediating various cytokine signaling, and has been developed as a target for autoimmune diseases such as RA. Tofacitinib, oral Pan-JAK inhibitor, demonstrated efficacy in RA patients, but its widespread use is limited by safety issues. Baricitinib, JAK1/2 inhibitor, is also known to interfere with the hematopoiesis system, such as anemia and thrombocytopenia associated with suppression of JAK2 signals. Therefore, it is necessary to develop a new potent compound that selectively inhibits JAK1 over JAK2, 3Objectives:To identify the pharmacological characteristic based on efficacy of CJ-15314 as potent and selective JAK1 inhibitor for treatment of autoimmune disease.Methods:In vitro, cell-based, kinase panel, Kd value and human whole blood assay were performed to determine the inhibition potency and selectivity for JAK subfamily kinases. In vivo therapeutic potential was evaluated by RA model including rat Adjuvant-Induced Arthritis (AIA) and collagen-induced arthritic (CIA). To confirm the possibility of further expansion into the autoimmune disease, BioMAP® Diversity PLUS® Panel was performed by discoverX.Results:In vitro assay, CJ-15314 inhibited JAK kinase family in a concentration-dependent manner with IC50 values of 3.8 nM against JAK1, Selectivity for JAK1 over JAK2, 3 was approximately 18, 83 fold greater for CJ-15314. In 1mM ATP condition, CJ-15314 has been confirmed to have the highest JAK1 selectivity over competing drugs, under 1 mM ATP condition that reflects the physiological environment in the body. Similarly, Kd values has also confirmed the selectivity of JAK1, which is 10 fold higher than JAK2, 3. Accordingly, in human whole blood assays, CJ-15314 is 11 fold more potent against IL-6 induced pSTAT1 inhibition through JAK1 (IC50 value: 70 nM) than GM-CSF-induced pSTAT5 inhibition (JAK2) whereas baricitinib and filgotinib exhibited only 2 fold and 7 fold respectively.In vivo efficacy model, CJ-15314 inhibited disease severity scores in a dose dependent manner. In the rat AIA model, CJ-15314 at 30 mg/kg dose showed 95.3% decrease in arthritis activity score, 51.2% in figotinib at 30 mg/kg, 97.7% showed baricitinib at 10 mg/kg. CJ-15314 showed superior anti-arthritic efficacy than filgotinib. CJ-15314 also minimally affected anemia-related parameters but not bricitinib end of the 2-week treatment. In the rat CIA model, like 10 mg/kg of bricitinib, 30 mg/kg of CJ-15314 also has a similar effect, with a significant reduction in histopathological scores.In biomap diversity panel, CJ-15314 inhibited the expression of genes such as MCP-1, VCAM-1, IP-10, IL-8, IL-1, sTNF-α and HLA-DR confirming the possibility of expansion into other diseases beyond arthritis.Conclusion:CJ-15314 is a highly selective JAK1 inhibitor, demonstrates robust efficacy in RA animal model and is good candidate for further development for inflammatory diseases.* CJ-15314 is currently conducting a phase I trial in south Korea.References:[1]Clark JD et al. Discovery and development of Janus kinase (JAK) inhibitors for inflammatory diseases. J Med Chem. 2014; 57(12):5023-38.[2]Burmester GR et al. Emerging cell and cytokine targets in rheumatoid arthritis. Nat Rev Rheumatol. 2014; 10(2):77-88[3]Jean-Baptiste Telliez et al. Discovery of a JAK3-selective inhibitor: functional differentiation of JAK3-selective inhibition over pan-JAK or JAK1-selective inhibition. ACS Chem. Biol., 2016; 11 (12):3442-3451Disclosure of Interests:so young Ki Employee of: CJ healthcare, hyunwoo shin Employee of: CJ healthcare, yelim lee Employee of: CJ healthcare, Hyoung rok Bak Employee of: CJ healthcare, hana yu Employee of: CJ healthcare, Seung Chan Kim Employee of: CJ healthcare, juhyun lee Employee of: CJ healthcare, donghyun kim Employee of: CJ healthcare, Dong-hyun Ko Employee of: CJ Healthcare, dongkyu kim Employee of: CJ healthcare

In vitro T2 relaxivities of the Gd-based contrast agents (GBCAs) in human blood at 1.5 and 3 T

2018 ◽  
Vol 60 (6) ◽  
pp. 694-701 ◽  
Author(s):  
Yaqi Shen ◽  
Frank L Goerner ◽  
Johannes T Heverhagen ◽  
Christopher Snyder ◽  
Daoyu Hu ◽  
...  
Keyword(s):  
Body Temperature ◽  
Contrast Agents ◽  
Whole Blood ◽  
Medical Literature ◽  
Theoretical Calculations ◽  
Clinical Impact ◽  
Human Whole Blood ◽  
Comprehensive Comparison ◽  
The Relationship

Background The availability of data in the medical literature for the T2 relaxivities of the Gd-based contrast agents (GBCAs) is limited. A comprehensive comparison between the agents available commercially (other than in Europe) is lacking, with no data available that most closely reflect the clinic, which is in human whole blood at body temperature. Purpose To complement the existing literature by determining T2 relaxivity data for eight GBCAs in vitro. Material and Methods The relaxivities of eight GBCAs diluted in human whole blood at 1.5 and 3 T were determined at 37 ± 0.5 °C. Gd was in the range of 0–4 mM. Multi-echo sequences with variable echo times were acquired using a phantom containing a dilution series with each agent, and SigmaPlot 12.0 was used to calculate the R2 relaxation rate and finally r2. Statistical comparisons between agents and field strengths were conducted. Results The relationship between R2 vs. Gd was observed to be linear at 1.5 and 3 T, with a mild increase in r2 from 1.5 to 3 T for all GBCAs. T2 relaxivity data were compared with prior results. The GBCAs are closely clustered into two groups, with higher r2 noted for the two lipophilic (those with partial hepatobiliary excretion) compounds. Conclusion The r2 values at 1.5 and 3 T, determined for the eight GBCAs still clinically available (other than in Europe), provide a definitive baseline for future evaluations, including theoretical calculations of signal intensity and their clinical impact on T2-weighted scans.

Endotoxin-Induced Platelet Activation in Human Whole Blood In Vitro

1988 ◽  
Vol 59 (03) ◽  
pp. 378-382 ◽  
Author(s):  
Gyorgy Csako ◽  
Eva A Suba ◽  
Ronald J Elin
Keyword(s):  
Platelet Aggregation ◽  
Whole Blood ◽  
Human Platelet ◽  
Platelet Rich Plasma ◽  
Atp Release ◽  
Human Platelets ◽  
Lag Phase ◽  
Human Whole Blood ◽  
Dose Dependent

SummaryThe effect of purified bacterial endotoxin was studied on human platelets in vitro. In adding up to 1 μg/mL of a highly purified endotoxin, we found neither aggregation nor ATP release in heparinized or citrated human platelet-rich plasma. On the other hand, endotoxin at concentrations as low as a few ng/mL (as may be found in septic patients) caused platelet aggregation in both heparinized and citrated human whole blood, as monitored by change in impedance, free platelet count, and size. Unlike collagen, the platelet aggregation with endotoxin occurred after a long lag phase, developed slowly, and was rarely coupled with measurable release of ATP. The platelet aggregating effect of endotoxin was dose-dependent and modified by exposure of the endotoxin to ionizing radiation. Thus, the activation of human platelets by “solubilized” endotoxin in plasma requires the presence of other blood cells. We propose that the platelet effect is mediated by monocytes and/or neutrophils stimulated by endotoxin.

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