Numerical Study on the Impact of Central Venous Catheter Placement on Blood Flow in the Cavo-Atrial Junction.

An in silico study is performed to investigate fluid dynamic effects of central venous catheter (CVC) placement within patient-specific cavo-atrial junctions. Prior studies show the CVC infusing a liquid, but this study focuses on the placement without any liquid emerging from the CVC. A 7 or 15-French double-lumen CVC is placed virtually in two patient-specific models; the CVC tip location is altered to understand its effect on the venous flow field. Results show that the CVC impact is trivial on flow in the superior vena cava when the catheter-to-vein ratio ranges from 0.15 to 0.33. Results further demonstrate that when the CVC tip is directly in the right atrium, flow vortices in the right atrium result in elevated wall shear stress near the tip hole. A recirculation region characterizes a spatially variable flow field inside the CVC side hole. Furthermore, flow stagnation is present near the internal side hole corners but an elevated wall shear stress near the curvature of the side hole's exit. These results suggest that optimal CVC tip location is within the superior vena cava, so as to lower the potential for platelet activation due to elevated shear stresses and that CVC geometry and location depth in the central vein significantly influences the local CVC fluid dynamics. A thrombosis model also shows thrombus formation at the side hole and tip hole. After modifying the catheter design, the hemodynamics change, which alter thrombus formation. Future studies are warranted to study CVC design and placement location in an effort to minimize CVC-induced thrombosis incidence.

Saccharides from Arctium lappa L. root reduce platelet activation and thrombus formation in a laser injury thrombosis mouse model.

Arctium lappa L., also known as burdock, is a popular medicinal plant in traditional Chinese medicine due to its potential therapeutic properties. Saccharides from Arctium lappa L. root (ALR-S) have been extensively studied for their anti-inflammatory and anti-diabetes effects. Platelets play a pivotal role in thrombosis. The present study describes the effects of ALR-S on platelet activation and thrombosis using a laser injury thrombosis in vivo model. The study also measured the effects of ALR-S on platelet activation by analysing aggregation, ATP release, platelet spreading, adhesion and clot retraction in vitro. Specifically, the effects were ALR-S concentration-dependent inhibition of platelet aggregation and ATP release. Activated platelets pretreated with ALR-S showed diminished CD62P expression levels and fibrinogen binding, as measured by flow cytometry. ALR-S inhibited platelet spreading on fibrinogen and adhesion on collagen under shear. ALR-S attenuated platelet activation by decreasing oxidative stress and thrombus formation. These results demonstrated the antiplatelet effects of ALR-S, suggesting the antithrombotic and cardiovascular protective activities of ALR-S as a functional food.

The feasibility of ultrasound-assisted endovascular laser thrombolysis in an acute rabbit thrombosis model.

PURPOSE: This study aimed to test the feasibility of combined ultrasound and laser technique, namely, ultrasound-assisted endovascular laser thrombolysis (USELT), for thrombolysis by conducting in vivo tests in a rabbit thrombosis model. MATERIALS AND METHODS: An acute thrombus was created in the right jugular vein of rabbit and then was treated with ultrasound only, laser only, and USELT to dissolve the blood clot. A total of 20 rabbits were used. Out of which, the first three rabbits were used to titrate the laser and ultrasound parameters. Then, five rabbits were treated with ultrasound only, five rabbits were treated with laser only, and seven rabbits were treated with USELT. During USELT, 532-nm laser pulses were delivered endovascularly directly to the clot through a fiber optic, and 0.5 MHz ultrasound pulses were applied noninvasively to the same region. A laser fluence of 4 to 12 mJ/cm2 and ultrasound amplitude of 1 to 2 MPa were used. Recanalization of the jugular vein was assessed by performing ultrasound Doppler imaging immediately after the treatment. The maximum blood flow speed after the treatment as compared to its value before the treatment was used to calculate the blood flow recovery in vessel. RESULTS: The blood flow was fully recovered (100%) in three rabbits, partially recovered in two rabbits (more than 50% and less than 100%) with mean percentage recovery of 69.73% and poorly recovered in two rabbits (<50%) with mean percentage recovery of 6.2% in the USELT group. In contrast, the treatment group with ultrasound or laser alone did not show recanalization of vein in any case, all the five rabbits were poorly/not recovered with a mean percentage recovery of 0%. CONCLUSIONS: The USELT technology was shown to effectively dissolve the blood clots in an acute rabbit jugular vein thrombosis model.

A Bioassay-Based Approach for the Batch-To-Batch Consistency Evaluation of Xuesaitong Injection on a Zebrafish Thrombosis Model.

Quality control of Chinese medicine (CM) is mainly based on chemical testing, which sometimes shows weak correlation to pharmacological effects. Thus, there is a great demand to establish bioactivity-based assays to ensure the quality of CM. The aim of the present study was to establish a bioassay-based approach to evaluate the biological activity of Xuesaitong injection (XST) based on an in vivo zebrafish model. Zebrafish larvae with arachidonic acid (AA)-induced thrombus were applied to evaluate anti-thrombosis effects of XST and explore the potential mechanism of XST. Analysis of major components in normal and abnormal XST samples was performed by high performance liquid chromatography (HPLC). The results indicate that XST could significantly restore heart red blood cells (RBCs) intensity of thrombotic zebrafish in a dose-dependent manner, whilst decreasing RBCs accumulation in the caudal vein. The results were confirmed using a green fluorescence protein (GFP)-labeled zebrafish thrombosis model. Moreover, we could show that XST downregulates the expression of the fibrinogen alpha chain (fga) gene to inhibit the coagulation cascade during the process of thrombosis in zebrafish. Notoginsenoside R1, ginsenoside Rg1, ginsenoside Rb1 and ginsenoside Rd, which were considered to be the major components of XST, also showed moderate anti-thrombosis efficacy. Further results showed that the zebrafish thrombosis model could efficiently distinguish five abnormal batches of XST from 24 normal batches. Furthermore, the inhibition rates of different batches were correlated with the content level of major components. Our results suggested that the proposed zebrafish thrombosis model could be successfully used to evaluate the batch-to-batch consistency of XST, which provided an alternative way for the quality control of CM.

Naoxintong restores ischemia injury and inhibits thrombosis via COX2-VEGF/ NFκB signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Naoxintong (NXT) is a traditional Chinese medicine preparation that is often used in combination with aspirin in the treatment of cardiovascular diseases (CVD). One of the main symptoms of CVD is hypoxic-ischemia (HI). The purpose of this study is to find out the molecular nodes targeted by NXT and its related molecular pathways in vascular repair. MATERIALS AND METHODS: First, human vein umbilical endothelial cells (EA.hy926) were utilized to set up the Oxygen-Glucose Deprivation-Reoxygenation (OGD/R) model and treated with NXT. Cell proliferation, damage and apoptosis were detected by MTT, LDH, and flow cytometry assays. Second, transcriptional responses of OGD/R cells to NXT treatment were investigated. qRT-PCR, western blotting and inhibitor assays were performed. Third, the anti-thrombotic effect of NXT was evaluated by the zebrafish thrombosis model. Morphological observation, histological staining and qRT-PCR assays were implemented on zebrafish model to further observe in vivo the therapeutic effects of NXT on ischemia and thrombosis. RESULTS: In OGD/R EA.hy926 cells, NXT treatment could reduce ischemic vascular injury, increase cell viability and decrease the proportion of apoptosis. Through RNA-seq analysis, 183 differentially expressed genes (DEGs) were screened with 110 up-regulated genes and 73 down-regulated genes between OGD/R and OGD/R + NXT treated EA.hy926 cells. VEGF and NFκB pathways were enriched. Among these genes, COX2 was identified as one of important targets via which NXT could restore vascular injury. COX2 inhibitor (NS-398), and aspirin, a drug that prevents the development of CVD by targeting COX2, exhibited similar effects to NXT in the treatment of OGD/R EA.hy926 cells. In zebrafish thrombosis model, NXT could attenuate tail venous thrombus and recover the quantity of heart red blood cells. Furthermore, NXT could prevent the formulation of thrombosis and eliminate inflammation in zebrafish by COX2-VEGF/NFκB signaling. CONCLUSION: Our studies implicated that NXT could restore HI injury and inhibit thrombosis through COX2-VEGF/NFκB signaling, which is consistent with the molecular target of aspirin. This finding might explain the principle of NXT combined with aspirin in the treatment of cardiovascular diseases.

Antithrombotic effect and action mechanism of Salvia miltiorrhiza and Panax notoginseng herbal pair on the zebrafish.

BACKGROUND: Salvia miltiorrhiza (Danshen, DS) and Panax notoginseng (Sanqi, SQ) are famous traditional Chinese herbs, and their herbal pair (DS-SQ) has been popular used as anti-thrombotic medicines. However, there is still a lack of sufficient scientific evidence to illustrate the optimum combination ratio of these two herbs as well as its action mechanisms. The purpose of this study is to investigate the anti-thrombotic effects of DS-SQ on zebrafish and explore its possible action mechanism. METHODS: Firstly, the chemical components in DS-SQ extract were analyzed by LC-ESI-MS/MS. Then, a phenylhydrazine (PHZ)-induced zebrafish thrombosis model was developed for evaluating the anti-thrombotic effects of DS-SQ extracts with different combination ratios and their nine pure compounds. Followed, Real-time quantitative PCR (RT-qPCR) assays were performed to investigate the potential antithrombotic mechanisms of DS-SQ. RESULTS: Thirty-three components were tentatively identified by LC-MS analysis. DS-SQ at the ratio of 10:1 presented the best anti-thrombotic effect, and rosmarinic acid, lithospermic acid and salvianolic acid B of DS showed good anti-thrombotic activity on zebrafish thrombosis model. The RT-qPCR assays indicated that DS-SQ (10:1) could cure the PHZ-induced thrombosis by downregulating the expression of PKCα, PKCß, fga, fgb, fgg and vWF in zebrafish. CONCLUSIONS: DS-SQ with the combination ratio of 10:1 showed optimum anti-thrombotic effect on PHZ-induced zebrafish thrombosis model, which provided a reference for reasonable clinical applications of DS-SQ herbal pair.

New experimental animal model of intracardiac thrombus created with epicardial echocardiographic guidance.

BACKGROUND: Models of intracardiac thrombus are very difficult to establish and have rarely been reported. We designed and established a new, inexpensive, practical animal model for intracardiac thrombus created with epicardial echocardiographic guidance. METHODS: Male New Zealand white rabbits weighing 2 to 3.9 kg (3.10±0.58 kg) were used in this study. Cylindrical thrombi were created in plastic tubing and then aspirated with saline into a syringe. The thrombus in saline suspension was then slowly injected into a heart chamber and confirmed with echocardiography, including two-dimensional and contrast-enhanced ultrasound. RESULTS: Intracardiac thrombi were created successfully in the left ventricle, right ventricle, and left and right atrial appendages. The average preparation time was about 3 hours. There were no significant differences among the four heart chambers in the success rate of thrombus model creation. Thrombi embolized to the pulmonary artery after failure of the right heart model. After failure of the left heart model, emboli were found in the carotid artery, renal artery, and truncus coeliacus. In two cases thrombi extended from the left ventricular apex into the aorta and in one case the thrombus extended from the left atrial appendage to the left atrium; there was no such extension from the other chambers. The rabbits' vital signs remained stable after establishment of the model, with no significant changes in heart structure or function. CONCLUSIONS: This new method of creating an intracardiac thrombus model in rabbits showed initial success.

Choosing a mouse model of venous thrombosis: a consensus assessment of utility and application.

Murine models are widely used valuable tools to study deep vein thrombosis (VT). Leading experts in VT research came together through the American Venous Forum to develop a consensus on maximizing the utility and application of available mouse models of VT. In this work, we provide an algorithm for model selection, with discussion of the advantages, disadvantages, and applications of the main mouse models of VT. Additionally, we provide a detailed surgical description of the models with guidelines to validate surgical technique.

Identification of a Quality Marker (Q-Marker) of Danhong Injection by the Zebrafish Thrombosis Model.

Quality-marker (Q-marker) is an emerging concept to ensure the quality and batch-to-batch consistency of Chinese medicine (CM). However, significant difficulties remain in the identification of Q-markers due to the unclear relationship between complex chemical compositions and the pharmacological efficacy of CM. In the present study, we proposed a novel strategy to identify the potential Q-marker of danhong injection (DHI) by an in vivo zebrafish thrombosis model. The anti-thrombotic effects of DHI and its major constituents were evaluated by the zebrafish model of arachidonic acid (AA)-induced thrombosis. The results indicated that DHI can attenuate tail venous thrombus and recover the decrease of heart red blood cell (RBC) intensity in a dose-dependent manner. The result that DHI prevented the formulation of thrombosis in zebrafish was also validated in the zebrafish thrombosis model with green fluorescence protein (GFP)-labeled hemoglobin. The major components of DHI, namely danshen (DS) and honghua (HH), as well as the major chemical constituents of DHI, also exerted anti-thrombotic effects, among which rosmarinic acid (RA) and p-coumaric acid (pCA) showed moderate anti-thrombotic effects. This is the first time that pCA from HH has been found as an active compound exerting an anti-thrombotic effect in a dose-dependent manner, whose IC50 value is approximately 147 µg/mL. By analyzing 10 batches of normal DHI samples and five abnormal samples by high-performance liquid chromatography (HPLC), we found the contents of pCA and RA can be positively correlated to the anti-thrombotic effect of DHI, suggesting that pCA and RA could be potential Q-markers of DHI to ensure batch-to-batch consistency. Our findings illustrated that discovering major active compounds from CM by in vivo pharmacological models can be a useful approach to identifying Q-markers of CM, and in vivo pharmacological models can be a potential tool to evaluate batch-to-batch consistency of CMs.

Applicability of Zebra Fish Thrombosis Model in Antithrombotic Activity Screening of Chinese Materia Medica / 中国中医药信息杂志

Objective To investigate the applicability of zebra fish thrombosis model in antithrombotic activity screening of Chinese materia medica.Methods The living zebra fish thrombosis model was induced by adrenaline hydrochloride. Zebra fish were randomly divided into blank control group, model group, positive medicine group and medication group. Each group was given the corresponding medicine or embryo culture water. O-anisidine staining solution was used to stain and calculate the staining intensity of erythrocytes in zebra fish heart, and quantitative analysis was carried out. The platelet aggregation of transgenic zebra fish was observed and under qualitative analysis. Results Compared with the model group, 100μg/mL salvianolic acid B, 300, 900μg/mL aqueous extract of Salvia miltiorrhiza, 45μg/mL 95% ethanol extract and 400, 1200μg/mL hypothalamus could significantly inhibited the formation of zebra fish thrombosis (P<0.01).ConclusionZebra fish thrombosis model has good applicability in antithrombotic activity screening of Chinese materia medica.

Establishment of a zebrafish model of thrombosis and the intervention effect of Guanxinning tablet / 中国实验动物学报

Objective To establish a zebrafish model of thrombosis induced by three kinds of inducers and observe the anti?thrombotic effect of a Chinese traditional medicine, Guanxinning tablet ( GXN) . Methods The zebrafish models of thrombosis was induced by using 1?5μmol/L phenyl hydrazine, 80μmol/L arachidonic acid and 5 mg/L ponatinib, re?spectively, and were treated with various concentration of GXN, clopidogrel or asprin. The thrombus in the tail vein was observed under microscope, Erythrocytes in the zebrafish heart were stained with o?dianisidine and the erythrocyte staining intensity was assessed with a NIS?Elements DTM image analyzer, and the anti?thrombolic effect of GXN was calculated. Results Venous thrombus was significantly increased and the staining intensities of erythrocytes in the heart were signifi?cantly decreased after induction by phenyl hydrazine, arachidonic acid or Ponatinib ( P <0?001 ) , respectively. At the same time, GXN showed an incresing anti?thrombolic effect in the zebrafish models (P<0?001) in a dose?effect manner, with a IC50 of GXN of 44?32 mg/L,138?5 mg/L and 459?5 mg/L, respectively. Conclusions The zebrafish models of thrombosis are successfully established by phenyl hydrazine, arachidonic acid or Ponatinib, respectively, by different for?mation mechanisms. GXN has been shown to have an anti?thrombosis effect, probably, by multiple target effects.

Localized lower extremity ischemic preconditioning prevents against local thrombus formation.

BACKGROUND: Ischemic preconditioning (IPC) has many beneficial effects on the cardiovascular system. However, whether localized lower extremity IPC could be protective against the thrombogenic activity generated by lower extremity ischemia is unclear. MATERIAL AND METHODS: 41 male Sprague-Dawley rats were randomly assigned to either a IPC group or a sham group. The lower extremity blood inflow was previously treated with 4 cycles of 5 min ischemia followed by 5 min of reperfusion by clamping the abdominal aortic just before ligature of the left iliac vein(LIV) in the IPC group. Rats in the sham group had a 40-minute blank before left iliac vein ligation. The rats were euthanized at day 2 after ligation and the thrombosed LIV was carefully dissected out, while thrombi harvested from the LIV were measured with weight (g), length (mm) and weight/length (mg/mm). Influence of IPC on coagulation function was also tested. RESULTS: 21 and 20 rats were randomly assigned to einter the IPC group or the control group. Left iliac vein thrombosis was successfully generated in all 41 rats. IPC significantly protects the rats from experimental lower extremity thrombosis. Compared to control group, generated thrombus in rats in the IPC group showed significantly lower weight (2.73 ± 0.16 mg vs 1.82 ± 0.13 mg, P < 0.001), length (2.99 ± 0.17 mm vs 2.44 ± 0.08 mm, P < 0.009) and density (0.95 ± 0.05 mg/mm vs 0.75 ± 0.05 mg/mm, P = 0.01). Influence on coagulation function by IPC itself was not significant (P > 0.05). CONCLUSIONS: Our study demonstrated that localized lower extremity IPC could reduce DVT formation in rats in an in vivo experimental thrombosis model.

Pharmacological study of zomoshin-6 tan / Монголын Анагаах Ухаан

IntroductionNowadays the risk factors for thrombosis include blood stasis, vessel wall injury, and hypercoagulability, as proposed by Virchow over 150 years ago. We chose to study affect of Zomoshin 6 tan to the model of thrombosis formed in experimental animal. It was written in books and sudar that it has action of treating some type’s disease such as blood diluting, meeting frozen blood and treating some gynecological disease.PurposeTo study affect of Zomoshin-6 tan deep vein thrombosis model formed in experimental animal.Material and Methods30 male rats of wistar bread with 180-220 gram of weight for control group, experimental group or Zomoshin-6 tan and comparative group Warfarin. Thirty rats were equally divided into 3 groups: Group 1 received saline alone, Group 2 received Zomoshin-6 (200 mg/kg), and Group 3 received Warfarin as a positive control (0.25 mg/kg), seven days prior to the assessment of thrombus formation. Thrombus formation was also assessed histopathologically. Thrombi were detected in all rats after experimentallyinduced thrombosis.ResultsHistological analysis demonstrated the presence of thrombosis in the interior vena cava (IVC) of the control group, which contained fibrin, erythrocytes, and leucocytes and obstructed the lumen. Only a small amount of fibrin clot, containing a few leucocytes and large numbers of erythrocytes, were observed in the Zomoshin-6-treated group. The thrombus formed in the IVC of Warfarin-treated animals consisted of fibrin clot, which was mostly attached to the wall, with few leucocytes but abundant erythrocytes. These findings suggest that Zomoshin-6 is an effective antithrombotic agent.Conclusion:Zomoshin-6 tan has an action of inhibing thrombosis forming of vein in experimental animal.

Neuroprotective Effect and Anticoagulation Effect of Total Saponins of Radix Liriopes on Focal Cerebral Ischemia / 中国药房

OBJECTIVE:To investigate the neuropotective effect and anticoagulation effect of total Saponins of Radix Liriopes on focal cerebral ischemia in rats.METHODS:Chemical reagent Fecl3 was locally applied on the injured vessels to establish middle cerebral artery thrombosis model,and the effects of total Saponins of Radix Liriopes on rats' behavioral disturbance,brain infarct size,the histopathological changes in brain and the expression rate of nNOS immunoreactive positive neurons were measured,and the bleeding time and coagulation time were also detected with glass tube method and tail transection method.RESULTS:Due to the use of total Saponin of Radix Liriopes(10 and 40mg? kg-1),the brain infarct size was significantly decreased,the behavioral disturbance were improved and the expression rate of the nNOS immunoreactive positive neurons in rats were decreased.At doses of 20 and 60mg? kg-1,total Saponin of Radix Liriopes significantly prolonged the coagulation time and bleeding time.CONCLUSION:Total Saponin of Radix Liriopes has nuroprotective effect on focal cerebral ischemia induced by middle cerebral artery thrombosis and significant anticoagulation effect.