In silico evidence of Remdesivir action in blood coagulation cascade modulation in COVID-19 treatment

BACKGROUND Coronavirus disease 2019(COVID-19)has demonstrated several clinical manifestations which include not only respiratory system issues but also liver,kidney,and other organ injuries.One of these abnormalities is coagulopathies,including thrombosis and disseminated intravascular coagulation.Because of this,the administration of low molecular weight heparin is required for patients that need to be hospitalized.In addition,Remdesivir is an antiviral that was used against Middle East Acute Respiratory Syndrome,Ebola,Acute Respiratory Syndrome,and other diseases,showing satisfactory results on recovery.Besides,there is evidence suggesting that this medication can provide a better prognosis for patients with COVID-19.AIM To investigate in silico the interaction between Remdesivir and clotting factors,pursuing a possibility of using it as medicine.METHODS In this in silico study,the 3D structures of angiotensin-converting enzyme 2(ACE2),Factor I(fibrinogen),Factor II(prothrombin),Factor III(thromboplastin),Factor V(proaccelerin),Factor VII(proconvertin),Factor VIII(antihemophilic factor A),Factor IX(antihemophilic factor B),Factor X(Stuart-Prower factor),and Factor XI(precursor of thromboplastin(these structures are technically called receptors)were selected from the Protein Data Bank.The structures of the antivirals Remdesivir and Osetalmivir(these structures are called ligands)were selected from the PubChem database,while the structure of Atazanavir was selected from the ZINC database.The software AutoDock Tools(ADT)was used to prepare the receptors for molecular docking.Ions,peptides,water molecules,and other ones were removed from each ligand,and then,hydrogen atoms were added to the structures.The grid box was delimited and calculated using the same software ADT.A physiological environment with pH 7.4 is needed to make the ligands interact with the receptors,and still the software Marvin sketch®(ChemAxon®)was used to forecast the protonation state.To perform molecular docking,ADT and Vina software was connected.Using PyMol®software and Discovery studio®software from BIOVIA,it was possible to analyze the amino acid residues from receptors that were involved in the interactions with the ligands.Ligand tortions,atoms that participated in the interactions,and the type,strength,and duration of the interactions were also analyzed using those software.RESULTS Molecular docking analysis showed that Remdesivir and ACE2 had an affinity energy of-8.8 kcal/moL,forming a complex with eight hydrogen bonds involving seven atoms of Remdesivir and five amino acid residues of ACE2.Remdesivir and prothrombin had an interaction with six hydrogen bonds involving atoms of the drug and five amino acid residues of the clotting factor.Similar to that,Remdesivir and thromboplastin presented interactions via seven hydrogen bonds involving five atoms of the drug and four residues of the clotting factor.While Remdesivir and Factor V established a complex with seven hydrogen bonds between six antiviral atoms and six amino acid residues from the factor,and Factor VII connected with the drug by four hydrogen bonds,which involved three atoms of the drug and three residues of amino acids of the factor.The complex between Remdesivir and Factor IX formed an interaction via 11 hydrophilic bonds with seven atoms of the drug and seven residues of the clotting factor,plus one electrostatic bond and three hydrophobic interactions.Factor X and Remdesivir had an affinity energy of-9.6 kcal/moL,and the complex presented 10 hydrogen bonds and 14 different hydrophobic interactions which involved nine atoms of the drug and 16 amino acid residues of the clotting factor.The interaction between Remdesivir and Factor XI formed five hydrogen bonds involving five amino acid residues of the clotting factor and five of the antiviral atoms.CONCLUSION Because of the in silico significant affinity,Remdesivir possibly could act in the severe acute respiratory syndrome coronavirus 2 infection blockade by interacting with ACE2 and concomitantly act in the modulation of the coagulation cascade preventing the hypercoagulable state.

Protective effects of Dragon's Blood on blood coagulation and NO/iNOS level in myocardium and serum of rats in simulated microgravity

To investigate effects of Dragon's Blood(DB),a traditional Chinese medicine,on blood coagulation and NO/iNOS level in myocardium and serum of rats in simulated microgravity for the first time,Sprague Dawley(SD)rats were randomly divided into six groups:(a)5-day control group,(b)5-day model group,(c)5-day drug group,(d)21-day control group,(e)21-day model group,and(f)21-day drug group.Blood coagulation and NO/iNOS level in myocardium and serum were examined after 5 and 21 days of simulated microgravity respectively.The results showed that blood of tail-suspended rats was in a hypercoagulable state that could not be converted with time extending.Conversely,DB changed these parameters towards normal level and the curative effects became better when tail-suspension lasted till the 21 st day.NO concentration of both myocardium and serum for two periods all increased markedly and DB could effectively reduce these increases except that of 21-day myocardium NO.Activity of iNOS increased markedly as early as 5 days and became more serious on the 21 st day,while DB showed preventive effect on the 21 st day.Western Blot analysis illustrated that the expression of iNOS in the 5-day model group increased significantly over the 5-day control group and the expression in the 5-day drug group dramatically returned to the normal level.The similar trend was observed on the 21-day groups without notable variances.The findings of this study can serve for the further use of Dragon's Blood in space diseases.

Clinical study on the related markers of blood coagulation in the patients with ANFH after SARS

The aim of this research was to investigate the blood coagulation function in the patients with avascular necrosis of the femoral head(ANFH)after severe acute respiratory syndrome(SARS).The expression of CD31,CD61,CD62p,CD63 and PAC-1 on platelet membrane was measured respectively by flowcytometry,and the plasma prothrombin time(PT),activated partial thromboplastin time(APTT),thrombin time(TT)and fibrinogen(Fbg)were mea-sured by blood clotting instrument in 26 patients with ANFH after SARS and in 17 healthy adults.The expression of CD31,CD61,CD 62p,CD63 and PAC-1 on platelet membrane in 26 patients was all lower than that in 17 healthy subjects(P<0.01).The levels of PT,APTT,TT and Fbg in 26 patients were all normal.There is no significant difference(P>0.05)in those markers between patients and 17 healthy adults.The blood may not be in hypercoagulable state in patients with ANFH after SARS.

Highly efficient artificial blood coagulation shortcut confined on Ca-zeolite surface

It is challenging to develop an in w'fro catalytic system to conduct natural surface-confined enzymatic reactions in a stable,efficient,and spatially defined manner.Here,we report that an artificial catalyst,which composes of trypsin and a calcium ion exchanged zeolite Y(trypsin/CaY),is capable of conducting surface-confined thrombin generation,and then constructs an artificial shortcut for classic,natural and complex blood coagulation cascade.The Ca2+within the microporous cages play a key role in trypsin/CaY hybrid through tuning the bio-inorganic interaction and spatial orientation of the protease,which allows trypsin/CaY to display greatly enhanced catalytic performance in coagulation process.The in vivo efficiency of the artificial coagulation shortcut is further confirmed in massive bleeding and hemophilia animal models.Rapid hemostasis is achieved by trypsin/CaY hybrid in a hemophilia A mice tail bleeding model,where natural clotting system fails in response to bleeding event due to factor VIII deficiency.In a rabbit lethal femoral artery injury model,the blood loss of the artificial catalyst is decreased by 4-7 fold when compared to state-of-art clay-or zeolite-based topical agents.

Mechanism of blood coagulation in common carp (Cyprinus carpio)

In vitro,carp blood was anticoagulated by using MgSO4 at a final concentration of 22.2 mmol L-1 and sodium citrate at a final concentration of 11.8 mmol L-1.The coagulation times for carp plasma diluted by ion-free water(1:1),and that of carp plasma to which thrombocytes and small lymphocytes were added,were measured at 23℃ using standard methods,and then contrasted with the coagulation times for plasma obtained from chickens and rabbits.The shapes of the thrombocytes and small lymphocytes,which were either wet mounted or stained with hematoxylin and eosin,were observed under a light microscope.We found that:(i)the coagulation reaction of carp blood was significantly(P<0.01)accelerated by the addition of ion-free water;(ii)the three types of blood cells(thrombocytes,small lymphocytes and red blood cells)promoted plasma coagulation to a similar extent(P>0.05);(iii)in carp Mg^(2+)plasma and K_(2)C_(2)O_(4) plasma,the thrombocytes were usually morphologically normal,but many small lymphocytes were destroyed and became aggregated;(iv)in the citrate plasma,thrombocytes were often aggregated,but the small lymphocytes were usually morphologically normal;and(v)the coagulation time for chicken and rabbit plasma was significantly extended by adding ion-free water.

Mathematical Model of Extrinsic Blood Coagulation Cascade Dynamic System

WTFZ] The blood coagulation system is very important to life. This paper presents a mathematical blood coagulation model for the extrinsic pathway. This model simulates clotting factor VIII , which plays an important role in the coagulation mechanism. The mathematical model is used to study the equilibrium stability, orbit structure, attractors and global stability behavior, with conclusions in accordance with the physiological phenomena. Moreover, the results provide information about blood related illnesses, which can be used for further study of the coagulation mechanism.

Perioperative coagulation activation after permanent pacemaker placement

BACKGROUND Bradyarrhythmias are typically treated with permanent pacemakers(PM). The elimination of bradyarrhythmia by PM implantation improves the patient’s quality of life and prognosis, but it can also result in a number of sequalae. It is still unclear how PM implantation affects the hemostasis system’s parameters and how such parameters relate to different consequences after PM placement.AIM To assess the blood coagulation factor activity in PM patients throughout the perioperative period.METHODS Patients treated in the Department of Surgical Therapy of Cardiac Arrhythmias and Pacing at the Ryazan State "Regional Clinical Cardiology Dispensary" from April 2020 to December 2021 were included in the study. Before surgery, 7 and 30 d after PM placement, peripheral venous blood samples were withdrawn to measure the level of blood coagulation factor Ⅰ(FⅠ) and the activity of blood coagulation factors Ⅱ(FⅡ), Ⅴ(FⅤ), Ⅶ(FⅦ), Ⅷ(FⅧ), ⅸ(Fⅸ), ⅹ(Fⅹ), Ⅺ(FⅪ), Ⅻ(FⅫ). We used an automatic coagulometer Sysmex CA 660(Sysmex Europe, Germany) and reagents from Siemens(Siemens Healthcare Diagnostics Products GmbH, Germany).RESULTS The study included 146 patients. The activity of factors FⅤ [147.7(102.1-247.55)% vs 103.85(60-161.6)% vs 81.8(67.15-130.65)%, P = 0.002], FⅧ [80.4(60.15-106.25)% vs 70.3(48.5-89.1)% vs 63.7(41.6-88.25)%, P = 0.039], Fⅸ [86.2(70.75-102.95)% vs 75.4(59.2-88.3)% vs 73.9(56.45-93.05)%, P = 0.014], Fⅹ [188.9(99.3-308.18)% vs 158.9(83.3-230)% vs 127.2(95.25-209.35)%, P = 0.022], FⅪ [82.6(63.9-103.6)% vs 69.75(53.8-97.6)% vs 67.3(54.25-98.05)%, P = 0.002], FⅫ [87.6(67.15-102.3)% vs 78.9(63.4-97.05)% vs 81.2(62.15-97.4)%, P < 0.001] decreased at 7 and 30 d after surgery;FⅡ activity [157.9(109.7-245.25)% vs 130(86.8-192.5)% vs 144.8(103.31-185.6)%, P = 0.021] decreased at 7 d and increased at 30 d postoperatively. There were no statistically significant changes in the FVII activity within 30 d after PM placement [182.2(85.1-344.8)% vs 157.2(99.1-259)% vs 108.9(74.9-219.8)%, P = 0.128]. Subgroup analysis revealed similar changes only in patients on anticoagulant therapy. FⅫ activity decreased in patients on antiplatelet therapy [82(65.8-101.9)% vs 79.9(63.3-97.1)% vs 89.7(75.7-102.5)%, P = 0.01] 7 d after surgery, returning to baseline values at 30 d postoperatively.CONCLUSION PM placement and anticoagulant therapy were associated with decreased activity of clotting factors FⅤ, FⅧ, Fⅸ, Fⅹ, FⅪ, FⅫ in the postoperative period. FⅧ activity did not decrease within 30 d after PM placement, which may indicate endothelial injury caused by lead placement.

Effects of Taohong Siwu Decoction on coagulation function and PI3K/AKT/mTOR pathway after femoral artery anastomosis in rabbits

Objective:To observe the effect of Taohong Siyu Decoction on the coagulation function and the signaling pathway of PI3K(phosphatidylinositol 3-kinase)/AKT(protein kinase B)/mTOR(mammalian target of rapamycin)after femoral artery anastomosis in rabbits.Methods:30 New Zealand white rabbits were divided into blank control group,model control group,papavine hydrochloride injection group and low,medium and high dose groups of Taohong Siwu decoction by random number table method,with 5 rabbits in each group.The rabbits in the model control group,papavine hydrochloride injection group and low,medium and high dose groups of Taohong Siwu decoction were treated with the femoral artery simple intermittent end-to-end suture model.After the successful modeling,the low,medium and high dose groups of Taohong Siwu decoction were given the Taohong Siwu decoction,while the model control group,the blank control group and papavine hydrochloride injection group were given the same amount of normal saline.APTT(activated partial thromboplastin time),FIB(fibrinogen)and PI3K/AKT/mTOR concentrations were measured in aural venous blood samples from six groups of rabbits 30min before operation and 1d,2D,3D and 7d after operation,respectively.Statistical analysis was conducted on the data of the six groups.Results:Compared with blank control group,APTT of model control group was significantly shortened 1d to 7d after operation(P<0.05),FIB values were significantly increased from 1d to 7d after operation(P<0.05);Compared with model control group,APTT in Taohong Siwu decoction low-dose,medium-dose and high-dose groups were significantly prolonged 1d to 7d after operation(P<0.05),FIB value of Taohong Siwu decoction medium and high dose groups decreased significantly from 1d to 7d after operation(P<0.05),the FIB value of Taohong Siwu decoction low-dose group was significantly decreased from 2d to 7d after surgery(P<0.05);Compared with papaverine hydrochloride injection group,APTT in Taohong Siwu decoction medium dose group was significantly prolonged 2d to 7d after surgery(P<0.05),APTT of Taohong Siwu decoction high-dose group was significantly prolonged on 1d to 7d after operation(P<0.05).FIB in Taohong Siwu decoction medium and high dose groups decreased significantly 1d to 7d after operation(P<0.05);Compared with the blank control group,the expression concentrations of PI3K,Akt and mTOR in serum of the model control group were significantly increased from 1d to 7d after surgery(P<0.05);Compared with the model control group,the expression levels of PI3K,Akt and mTOR in serum were significantly increased in the low dose group of Taohong Siwu decoction and Papaverine Hydrochloride Injection group on postoperative 7 days(P<0.05),Taohong Siwu decoction high-dose group was significantly increased from 1d to 7d after surgery(P<0.05),the expression concentrations of PI3K and Akt in Taohong Siwu decoction medium dose group were significantly increased from 2d to 7d after operation(P<0.05),mTOR expression levels were significantly increased from 3d to 7d after operation(P<0.05);Compared with papaverine hydrochloride injection group,the expression concentrations of PI3K,Akt and mTOR in serum of Taohong Siwu decoction medium dose group were significantly increased from 3d to 7d after operation(P<0.05),the expression concentrations of PI3K and mTOR in Taohong Siwu decoction high-dose group were significantly increased from 1d to 7d after operation(P<0.05),and the expression concentration of Akt increased significantly from 3d to 7d after operation(P<0.05).Conclusion:The Taohong Siwu decoction can improve the coagulation function of rabbit femoral artery anastomosis,prevent thrombosis,activate PI3K/Akt/mTOR signaling pathway,promote angiogenesis,and improve tissue ischemia after artery anastomosis.

Prediction of return of spontaneous circulation in outof-hospital cardiac arrest with non-shockable initial rhythm using point-of-care testing: a retrospective observational study

BACKGROUND:Out-of-hospital cardiac arrest(OHCA) is a public health concern, and many studies have been conducted on return of spontaneous circulation(ROSC) and its prognostic factors.Rotational thromboelastometry(ROTEM?), a point-of-care testing(POCT) method, has been useful for predicting ROSC in patients with OHCA, but very few studies have focused on patients with non-shockable rhythm. We examined whether the parameters of POCT could predict ROSC in patients with OHCA and accompanying non-shockable rhythm.METHODS:This is a single-center, retrospective observational study. Complete blood count,blood gas, and ROTEM POCT measurements were used. This study included patients with nontraumatic OHCA aged 18 years or older who were transported to the emergency department and evaluated using POCT between January 2013 and December 2021. The patients were divided into the ROSC and non-ROSC groups. Prehospital information and POCT parameters were compared using receiver operating characteristic(ROC) curve analysis, and further logistic regression analysis was performed.RESULTS:Sixty-seven and 135 patients were in the ROSC and non-ROSC groups,respectively. The ROC curves showed a high area under the curve(AUC) for K^(+) of 0.77(95%confidence interval [CI]:0.71–0.83) and EXTEM amplitude 5 min after clotting time(A5) of 0.70(95%CI:0.62–0.77). The odds ratios for ROSC were as follows:female sex 3.67(95%CI:1.67–8.04);K^(+)0.64(95%CI:0.48–0.84);and EXTEM A5 1.03(95%CI:1.01–1.06).CONCLUSION:In OHCA patients with non-shockable rhythm, K^(+) level and the ROTEM parameter EXTEM A5 may be useful in predicting ROSC.

Active gastrointestinal bleeding:Use of hemostatic forceps beyond endoscopic submucosal dissection

To the best of our knowledge,this is the f irst report of the application of hemostatic forceps in active gastrointestinal(GI) bleeding that is not related to endoscopic submucosal dissection.An 86-year-old woman with chronic intake of low-dose aspirin had a Dieulafoy's lesion of the third duodenal portion.Bleeding control with epinephrine injection was unsuccessful.A 60-year-old man presented with a bleeding ulcer in the duodenal bulb.Ten days after combined endotherapy,he had recurrent bleeding from two minimal lesions in the same location.A 66-year-old woman under combined antithrombotic treatment was referred to us for chronic GI bleeding of unexplained origin.Endoscopy revealed active diverticular bleeding in the second duodenal portion.A 61-year-old woman underwent endoscopic mucosal resection of superficial gastric adenocarcinoma,which was complicated with immediate bleeding.In all cases,the blood was washed out using a water-jet-equipped,single-channel gastroscope with a large working channel.The bleeding points were pinched and retracted with hemostatic forceps.Monopolar electrocoagulation was performed using an electrosurgical current generator.Hemostasis was achieved.No complications occurred.In conclusion,hemostatic forceps may be an effective as well as safe alternative approach for active GI bleeding of various origins.

Hemostasis Efficacy and Mechanism of Cold Atmospheric Air Plasma

The capacity of a cold atmospheric-pressure air plasma (CAAP) device for advanced first aid is presented. Using swine as an animal model, two trials: 1) a large, curved cut in hindquarters area and 2) amputation of a front leg, were performed. Cold atmospheric-pressure air plasma effluent, which carries reactive oxygen species (ROS) atomic oxygen (OI), is applied for wound treatments. Swift hemostasis of the wounds by the CAAP treatment was demonstrated. The pressure applied by a finger on the cut arteries in trial 1 and the tourniquet applied in trial 2 could be removed immediately after the treatment and there was no re-bleed in both cases. CAAP hemostasis mechanism was explored via in-vitro tests. The tests on sodium citrate mixed blood-droplet samples show that 1) the heat delivered by the CAAP has no impact on the observed clot formation, 2) plasma effluent activates platelets to promote coagulation state and cascade, and 3) the degree of clotting increases with the total amount of applied OI by means of the CAAP effluent. It took only 16 s of the CAAP treatment to reach full clotting, which was considerably shortened from the natural clotting time of about 25 minutes. The tests on smeared blood samples show that the reduction of the platelet count and the increase of RBC count are proportional to the amount of applied OI. A plausible CAAP hemostasis mechanism is concluded from the in vitro test results and the animal model trials.

Effects of dietary vitamin K_(3) levels on growth,coagulation,calcium content,and antioxidant capacity in largemouth bass,Micropterus salmoides

An 8-week feeding trial investigated the optimum dietary vitamin K3 requirements of largemouth bass.A total of 600 healthy fish(12.96±0.07 g)were fed diets containing varying levels of vitamin K3 at 0.78(K0),5.80(K5),10.82(K10),15.84(K15),and 20.85(K20)mg/kg with four replicates per level.Results showed that dietary vitamin K3 enhanced growth,with weight gain rate and specific growth rate in K15 trials significantly higher than K0 trials(P<0.05).No significant difference was observed in the content of crude protein,crude lipid,moisture,ash,and phosphorus in muscle tissue(P>0.05).However,the supplementation of vitamin K3 significantly contributed to calcium accumulation in muscle tissues and vertebrae(P<0.05)and increased red blood cell counts(P<0.05).The blood coagulation time decreased significantly with increasing dietary vitamin K3 from 0.78 to 10.82 mg/kg(P<0.05)before stabilizing(P>0.05).The antioxidant capacity was improved with the addition of vitamin K3,which was inconsistent with the changes in malondialdehyde and MK-4(a form of menaquinone)within liver and serum,suggesting that the toxicity of excessive artificial vitamin K3 may account for this difference.Using regression analysis,the appropriate dietary vitamin K3 levels within a largemouth bass diet was determined to be in the range of 9.93-15.22 mg/kg,which will provide a reference for the preparation of vitamin premix and artificial diet for largemouth bass.

羟乙基淀粉130/0.4的药理特性及生理影响

Hydroxyethy/ starch (HES) 130/0.4 is a novel HES solution for intravenous administration. Compared with previous HES solutions, it possesses better capacity effect, with minor adverse effects on coagulation train, teair and kidney functions. Incidence of hypersensitivity in relation with HES 130/0.4 is very low, At it’s quite safe in clinical use.