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Biswas D, Heo J, Sang P, Dey P, Han K, Ko JH, Won SM, Son D, Suh M, Kim HS, Ok JG, Park HJ, Baac HW. Micro-ultrasonic Assessment of Early Stage Clot Formation and Whole Blood Coagulation Using an All-Optical Ultrasound Transducer and Adaptive Signal Processing Algorithm. ACS Sens 2022; 7:2940-2950. [PMID: 36107765 DOI: 10.1021/acssensors.2c00875] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Abnormal formation of solid thrombus inside a blood vessel can cause thrombotic morbidity and mortality. This necessitates early stage diagnosis, which requires quantitative assessment with a small volume, for effective therapy with low risk to unwanted development of various diseases. We propose a micro-ultrasonic diagnosis using an all-optical ultrasound-based spectral sensing (AOUSS) technique for sensitive and quantitative characterization of early stage and whole blood coagulation. The AOUSS technique detects and analyzes minute viscoelastic variations of blood at a micro-ultrasonic spot (<100 μm) defined by laser-generated focused ultrasound (LGFU). This utilizes (1) a uniquely designed optical transducer configuration for frequency-spectral matching and wideband operation (6 dB widths: 7-32 MHz and d.c. ∼ 46 MHz, respectively) and (2) an empirical mode decomposition (EMD)-based signal process particularly adapted to nonstationary LGFU signals backscattered from the spot. An EMD-derived spectral analysis enables one to assess viscoelastic variations during the initiation of fibrin formation, which occurs at a very early stage of blood coagulation (1 min) with high sensitivity (frequency transition per storage modulus increment = 8.81 MHz/MPa). Our results exhibit strong agreement with those obtained by conventional rheometry (Pearson's R > 0.95), which are also confirmed by optical microscopy. The micro-ultrasonic and high-sensitivity detection of AOUSS poses a potential clinical significance, serving as a screening modality to diagnose early stage clot formation (e.g., as an indicator for hypercoagulation of blood) and stages of blood-to-clot transition to check a potential risk for development into thrombotic diseases.
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Affiliation(s)
- Deblina Biswas
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea.,School of Bioengineering and Food Technology, Shoolini University, Solan, Himachal Pradesh 173229, India
| | - Jeongmin Heo
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Pilgyu Sang
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Prasanta Dey
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kayoung Han
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Department of Biomedical Engineering, Department of Intelligent Precision Healthcare Convergence (IPHC), Biomedical Institute of Convergence (BICS), Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jong Hwan Ko
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Sang Min Won
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Donghee Son
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Minah Suh
- Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Department of Biomedical Engineering, Department of Intelligent Precision Healthcare Convergence (IPHC), Biomedical Institute of Convergence (BICS), Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyung Sik Kim
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jong G Ok
- Department of Mechanical and Automotive Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea
| | - Hui Joon Park
- Department of Organic and Nano Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Hyoung Won Baac
- Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
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Gao Q, Qi P, Wang J, Hu S, Yang X, Fan J, Li L, Lu Y, Lu J, Chen J, Wang D. Effects of diabetes mellitus complicated by admission hyperglycemia on clot histological composition and ultrastructure in patients with acute ischemic stroke. BMC Neurol 2022; 22:130. [PMID: 35382802 PMCID: PMC8981928 DOI: 10.1186/s12883-022-02660-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 03/29/2022] [Indexed: 11/10/2022] Open
Abstract
Background Type 2 diabetes mellitus (T2DM) affects the occurrence and prognosis of acute ischemic stroke (AIS). However, the impact of diabetes on thrombus characteristics is unclear. The relationship between the composition and ultrastructure of clots and DM with admission hyperglycemia was investigated. Methods Consecutive patients with AIS who underwent endovascular thrombus retrieval between June 2017 and May 2021 were recruited. The thrombus composition and ultrastructure were evaluated using Martius scarlet blue stain and scanning electron microscopy. Clot perviousness was evaluated via thrombus attenuation increase on computed tomography angiography (CTA) versus non-contrast CT. Patients with admission hyperglycemia DM (ahDM) and those without DM (nonDM) were compared in terms of thrombus composition, ultrastructure, and perviousness. Results On admission, higher NIHSS scores (17 vs. 12, respectively, p = 0.015) was evident in ahDM patients. After the 90-day follow-up, the rates of excellent outcomes (mRS 0–1) were lower in patients with ahDM (16.6%, p = 0.038), but functional independence (mRS 0–2) and handicapped (mRS 3–5) were comparable between patients with ahDM and nonDM. The outcome of mortality was higher in patients with ahDM (33.3%, p = 0.046) than in nonDM patients. Clots in patients with ahDM had more fibrin (39.4% vs. 25.0%, respectively, p = 0.007), fewer erythrocyte components (21.2% vs. 41.5%, respectively, p = 0.043), equivalent platelet fraction (27.7% vs. 24.6%, respectively, p = 0.587), and higher WBC counts (4.6% vs. 3.3%, respectively, p = 0.004) than in nonDM patients. The percentage of polyhedral erythrocytes in thrombi was significantly higher in ahDM patients than in nonDM patients (68.9% vs. 45.6%, respectively, p = 0.007). The proportion of pervious clots was higher in patients nonDM than in patients with ahDM (82.61% vs. 40%, respectively, p = 0.026). Conclusion Patients with ahDM presented with greater stroke severity on admission and poorer functional outcomes after 3 months. Clots in patients with ahDM had more fibrin, leucocytes, and fewer erythrocyte components than in patients nonDM. The content of polyhedral erythrocytes and impervious clots proportion were significantly higher in thrombi of patients with AIS and ahDM. Further research is required to validate these findings.
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Affiliation(s)
- Qun Gao
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China.,Graduate School of Peking Union Medical College, Beijing, China
| | - Peng Qi
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China
| | - Junjie Wang
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China
| | - Shen Hu
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China
| | - Ximeng Yang
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China
| | - Jingwen Fan
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China.,Peking University Fifth School of Clinical Medicine, Beijing Hospital, Beijing, China
| | - Ling Li
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, China.,Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, Beijing, China
| | - Yao Lu
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, China.,Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, Beijing, China
| | - Jun Lu
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China. .,Graduate School of Peking Union Medical College, Beijing, China.
| | - Juan Chen
- Department of Radiology, Beijing Hospital, National Center of Gerontology, Beijing, China. .,Beijing Institute of Geriatrics, Beijing Hospital, National Center of Gerontology, Beijing, China.
| | - Daming Wang
- Department of Neurosurgery, Beijing Hospital, National Center of Gerontology, No.1 DaHua Road, Dong Dan, Beijing, 100730, People's Republic of China. .,Graduate School of Peking Union Medical College, Beijing, China.
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Gajos G, Siniarski A, Natorska J, Ząbczyk M, Siudut J, Malinowski KP, Gołębiowska-Wiatrak R, Rostoff P, Undas A. Polyhedrocytes in blood clots of type 2 diabetic patients with high cardiovascular risk: association with glycemia, oxidative stress and platelet activation. Cardiovasc Diabetol 2018; 17:146. [PMID: 30466424 PMCID: PMC6251112 DOI: 10.1186/s12933-018-0789-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/14/2018] [Indexed: 01/14/2023] Open
Abstract
Background Little is known about factors that affect the composition of contracted blood clots in specific diseases. We investigated the content of polyhedral erythrocytes (polyhedrocytes) formed in blood clots and its determinants in type 2 diabetes (T2D) patients. Methods In 97 patients with long-standing T2D [median HbA1c, 6.4% (interquartile range 5.9–7.8)], we measured in vitro the composition of blood clots, including a clot area covered by polyhedrocytes using scanning electron microscopy and the erythrocyte compression index (ECI), defined as a ratio of the mean polyhedrocyte area to the mean native erythrocyte area. Moreover, plasma fibrin clot permeability (Ks), clot lysis time (CLT), thrombin generation, oxidative stress [total protein carbonyl (total PC), total antioxidant capacity and thiobarbituric acid reactive substances (TBARS)], and platelet activation markers were determined. The impact of glucose concentration on polyhedrocytes formation was assessed in vitro. Results Polyhedrocytes content in contracted clots was positively correlated with glucose (r = 0.24, p = 0.028), glycated hemoglobin (r = 0.40, p = 0.024), total cholesterol (r = 0.22, p = 0.044), TBARS (r = 0.60, p = 0.0027), P-selectin (r = 0.54, p = 0.0078) and platelet factor-4, PF4 (r = 0.59, p = 0.0032), but not with thrombin generation, platelet count, Ks or CLT. Patients who formed more polyhedrocytes (≥ 10th percentile) (n = 83, 85.6%) had higher glucose (+ 15.7%, p = 0.018), fibrinogen (+ 16.6%, p = 0.004), lower red blood cell distribution width (RDW, − 8.8%, p = 0.034), reduced plasma clot density (− 21.8% Ks, p = 0.011) and impaired fibrinolysis (+ 6.5% CLT, p = 0.037) when compared to patients with lesser amount of polyhedrocytes (< 10th percentile). ECI and the content of polyhedrocytes were strongly associated with total PC (r = 0.79, p = 0.036 and r = 0.67, p = 0.0004, respectively). In vitro an increase of glucose concentration by 10 mmol/L was associated with 94% higher polyhedrocytes content (p = 0.033) when compared to the baseline (7.1 mM). After adjustment for age, sex and fibrinogen, multiple regression analysis showed that RDW was the only independent predictor of polyhedrocytes content in T2D (OR = 0.61, 95% CI 0.39–0.92). Conclusions Poor glycemic control, together with enhanced platelet activation and oxidative stress, increase the content of polyhedrocytes in blood clots generated in T2D patients. Electronic supplementary material The online version of this article (10.1186/s12933-018-0789-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Grzegorz Gajos
- Department of Coronary Artery Disease and Heart Failure, Jagiellonian University Medical College, Prądnicka 80 St., 31-202, Kraków, Poland. .,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland.
| | - Aleksander Siniarski
- Department of Coronary Artery Disease and Heart Failure, Jagiellonian University Medical College, Prądnicka 80 St., 31-202, Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
| | - Joanna Natorska
- Institute of Cardiology, Jagiellonian University Medical College, Prądnicka 80 St., Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
| | - Michał Ząbczyk
- Institute of Cardiology, Jagiellonian University Medical College, Prądnicka 80 St., Kraków, Poland
| | - Jakub Siudut
- Institute of Cardiology, Jagiellonian University Medical College, Prądnicka 80 St., Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
| | - Krzysztof Piotr Malinowski
- Institute of Public Health, Faculty of Health Sciences, Jagiellonian University Medical College, Grzegórzecka 20 St., Kraków, Poland
| | - Renata Gołębiowska-Wiatrak
- Department of Coronary Artery Disease and Heart Failure, Jagiellonian University Medical College, Prądnicka 80 St., 31-202, Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
| | - Paweł Rostoff
- Department of Coronary Artery Disease and Heart Failure, Jagiellonian University Medical College, Prądnicka 80 St., 31-202, Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
| | - Anetta Undas
- Institute of Cardiology, Jagiellonian University Medical College, Prądnicka 80 St., Kraków, Poland.,John Paul II Hospital, Prądnicka 80 St., Kraków, Poland
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The Mechanical Characterisation of Bovine Embolus Analogues Under Various Loading Conditions. Cardiovasc Eng Technol 2018; 9:489-502. [DOI: 10.1007/s13239-018-0352-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 03/22/2018] [Indexed: 10/17/2022]
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Robinson RA, Herbertson LH, Sarkar Das S, Malinauskas RA, Pritchard WF, Grossman LW. Limitations of using synthetic blood clots for measuring in vitro clot capture efficiency of inferior vena cava filters. MEDICAL DEVICES-EVIDENCE AND RESEARCH 2013; 6:49-57. [PMID: 23690701 PMCID: PMC3656916 DOI: 10.2147/mder.s42555] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study was first to evaluate the clot capture efficiency and capture location of six currently-marketed vena cava filters in a physiological venous flow loop, using synthetic polyacrylamide hydrogel clots, which were intended to simulate actual blood clots. After observing a measured anomaly for one of the test filters, we redirected the focus of the study to identify the cause of poor clot capture performance for large synthetic hydrogel clots. We hypothesized that the uncharacteristic low clot capture efficiency observed when testing the outlying filter can be attributed to the inadvertent use of dense, stiff synthetic hydrogel clots, and not as a result of the filter design or filter orientation. To study this issue, sheep blood clots and polyacrylamide (PA) synthetic clots were injected into a mock venous flow loop containing a clinical inferior vena cava (IVC) filter, and their captures were observed. Testing was performed with clots of various diameters (3.2, 4.8, and 6.4 mm), length-to-diameter ratios (1:1, 3:1, 10:1), and stiffness. By adjusting the chemical formulation, PA clots were fabricated to be soft, moderately stiff, or stiff with elastic moduli of 805 ± 2, 1696 ± 10 and 3295 ± 37 Pa, respectively. In comparison, the elastic moduli for freshly prepared sheep blood clots were 1690 ± 360 Pa. The outlying filter had a design that was characterized by peripheral gaps (up to 14 mm) between its wire struts. While a low clot capture rate was observed using large, stiff synthetic clots, the filter effectively captured similarly sized sheep blood clots and soft PA clots. Because the stiffer synthetic clots remained straight when approaching the filter in the IVC model flow loop, they were more likely to pass between the peripheral filter struts, while the softer, physiological clots tended to fold and were captured by the filter. These experiments demonstrated that if synthetic clots are used as a surrogate for animal or human blood clots for in vitro evaluation of vena cava filters, the material properties (eg, elastic modulus) and dynamic behavior of the surrogate should first be assessed to ensure that they accurately mimic an actual blood clot within the body.
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Affiliation(s)
- Ronald A Robinson
- Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD, USA
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6
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Wu G, Krebs CR, Lin FC, Wolberg AS, Oldenburg AL. High sensitivity micro-elastometry: applications in blood coagulopathy. Ann Biomed Eng 2013; 41:2120-9. [PMID: 23649979 DOI: 10.1007/s10439-013-0817-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 04/19/2013] [Indexed: 11/30/2022]
Abstract
Highly sensitive methods for the assessment of clot structure can aid in our understanding of coagulation disorders and their risk factors. Rapid and simple clot diagnostic systems are also needed for directing treatment in a broad spectrum of cardiovascular diseases. Here we demonstrate a method for micro-elastometry, named resonant acoustic spectroscopy with optical vibrometry (RASOV), which measures the clot elastic modulus (CEM) from the intrinsic resonant frequency of a clot inside a microwell. We observed a high correlation between the CEM of human blood measured by RASOV and a commercial thromboelastograph (TEG), (R = 0.966). Unlike TEG, RASOV requires only 150 μL of sample and offers improved repeatability. Since CEM is known to primarily depend upon fibrin content and network structure, we investigated the CEM of purified clots formed with varying amounts of fibrinogen and thrombin. We found that RASOV was sensitive to changes of fibrinogen content (0.5-6 mg/mL), as well as to the amount of fibrinogen converted to fibrin during clot formation. We then simulated plasma hypercoagulability via hyperfibrinogenemia by spiking whole blood to 150 and 200% of normal fibrinogen levels, and subsequently found that RASOV could detect hyperfibrinogenemia-induced changes in CEM and distinguish these conditions from normal blood.
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Affiliation(s)
- Gongting Wu
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, CB 3255, Chapel Hill, NC 27599, USA
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7
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Platelet reactivity and the identification of acute coronary syndromes in the emergency department. J Thromb Thrombolysis 2008; 28:31-7. [PMID: 18600429 DOI: 10.1007/s11239-008-0242-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Accepted: 06/20/2008] [Indexed: 01/12/2023]
Abstract
Risk stratifying patients with potential acute coronary syndromes (ACS) in the Emergency Department is an imprecise and resource-consuming process. ACS cannot be ruled in or out efficiently in a majority of patients after initial history, physical exam, and ECG are analyzed. This has led to a reliance on cardiac markers of myocardial necrosis as a key means of making the diagnosis. Commonly used markers, CK-MB and troponin-I, have the drawback of delayed sensitivity. This has led to an ongoing search for one or more marker(s) that would be more sensitive in early ACS. With the central role that platelets play in the pathophysiology of coronary thrombosis, measures of platelet function represent one potential area where an early ACS marker might be identified. This review will focus on selected tests/markers of platelet function that have shown some promise with respect to the risk stratification of patients with potential ACS.
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Brophy DF, Martin EJ, Carr SL, Kirschbaum B, Carr ME. The effect of uremia on platelet contractile force, clot elastic modulus and bleeding time in hemodialysis patients. Thromb Res 2006; 119:723-9. [PMID: 16793120 DOI: 10.1016/j.thromres.2006.02.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Revised: 02/21/2006] [Accepted: 02/28/2006] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Uremic bleeding frequently occurs in dialysis patients. Although its mechanism is not well characterized, acquired platelet dysfunction has been implicated in its pathogenesis. Skin bleeding time has been used to characterize platelet dysfunction in this population. However, the bleeding time is prone to error. The goal of this study was to compare the bleeding time to the novel platelet function parameters platelet contractile force and clot elastic modulus as well as platelet aggregation studies in controls and patients receiving maintenance hemodialysis. MATERIALS AND METHODS Forty-five subjects completed this study (25 controls, 20 dialysis). All subjects had the Ivy skin bleeding time procedure performed, as well as the collection of whole blood samples for the determination of platelet contractile force, clot elastic modulus, % von Willebrand Factor antigen, and platelet aggregation studies. Pearson's correlation determined the relationships between skin bleeding time and platelet function and clot structure parameters and markers of renal dysfunction. RESULTS Bleeding time was significantly prolonged in the dialysis group relative to controls. The platelet function parameters were not significantly different between groups. There was a significant relationship between bleeding time and creatinine concentration, however, no relationship existed between bleeding time and platelet function parameters. CONCLUSIONS Skin bleeding time poorly correlates with measurements of platelet function. There were no significant differences noted in platelet function between the groups despite the prolongations in bleeding time in the dialysis group. These data may suggest that the bleeding time reflects perturbations in platelet adhesion or secretion, and not aggregation. Further study is needed to characterize platelet function in dialysis patients.
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Affiliation(s)
- Donald F Brophy
- Department of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298-0533, USA.
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9
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Small Iv W, Wilson T, Benett W, Loge J, Maitland D. Laser-activated shape memory polymer intravascular thrombectomy device. OPTICS EXPRESS 2005; 13:8204-8213. [PMID: 19498850 DOI: 10.1364/opex.13.008204] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A blood clot (thrombus) that becomes lodged in the arterial network supplying the brain can cause an ischemic stroke, depriving the brain of oxygen and often resulting in permanent disability. As an alternative to conventional clot-dissolving drug treatment, we are developing an intravascular laser-activated therapeutic device using shape memory polymer (SMP) to mechanically retrieve the thrombus and restore blood flow to the brain. Thermal imaging and computer simulation were used to characterize the optical and photothermal behavior of the SMP microactuator. Deployment of the SMP device in an in vitro thrombotic vascular occlusion model demonstrated the clinical treatment concept.
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10
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Brophy DF, Martin RJ, Gehr TWB, Carr ME. A hypothesis-generating study to evaluate platelet activity in diabetics with chronic kidney disease. Thromb J 2005; 3:3. [PMID: 15796773 PMCID: PMC1079955 DOI: 10.1186/1477-9560-3-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Accepted: 03/29/2005] [Indexed: 01/01/2023] Open
Abstract
Background It is well described that diabetes mellitus is a hypercoagulable state. It is also known that patients with renal dysfunction have impaired platelet aggregation and function. It is not well described how renal dysfunction affects the hypercoagulability associated with diabetes. This post-hoc sub-group analysis compares platelet function, clot structure and thrombin generation time at baseline, and following enoxaparin exposure in three groups of subjects. Methods 30 total subjects were evaluated in the three groups: Group I: normal controls (n = 10), Group II: subjects with renal dysfunction but without diabetes (n = 13), and Group III: subjects with concomitant diabetes and renal dysfunction (n = 7). For each subject, platelet contractile force (PCF), clot elastic modulus (CEM) and thrombin generation time (TGT) were simultaneously measured in whole blood at baseline, and following increasing enoxaparin antifactor Xa activity exposure. The group means for each parameter were determined and compared using one-way analysis of variance, with post-hoc Tukey-Kramer test. Results At baseline, subjects in Group III (diabetics with concomitant renal dysfunction) display significantly enhanced platelet activity, as measured by PCF (p = 0.003) and CEM (p = 0.03), relative to the non-diabetic Groups I and II. Subjects in Group II (renal dysfunction without diabetes) had significantly prolonged TGT values relative to controls when the antifactor Xa activity concentration reached 0.5 (p = 0.007), 1.0 (p = 0.005) and 3.0 IU/mL (p < 0.0001), respectively. There were no differences between Group II and Group III with respect to TGT at these antifactor Xa activity concentrations. When the antifactor Xa activity concentration reached 3.0 IU/mL, Groups II and III formed significantly less rigid blood clots (CEM p = 0.003) and also trended toward reduced PCF (p = 0.06) relative to Group I. Conclusion This hypothesis-generating sub-group analysis suggests that at baseline, patients with concomitant diabetes and renal dysfunction have significantly enhanced platelet activity (PCF), and form more rigid blood clots (CEM) compared to controls and subjects with renal dysfunction but no diabetes. This may suggest that the presence of renal dysfunction does not ameliorate the hypercoagulable state associated with diabetes. Secondly, it appears that subjects with renal dysfunction but without diabetes have an enhanced response to enoxaparin relative to controls.
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Affiliation(s)
- Donald F Brophy
- Department of Pharmacy Practice, Virginia Commonwealth University/Medical College of Virginia Campus (VCU/MCV), Richmond, VA, USA
- Department of Internal Medicine, VCU/MCV, Richmond, VA, USA
| | - rika J Martin
- Department of Internal Medicine, VCU/MCV, Richmond, VA, USA
- Coagulation Special Studies Laboratory, VCU/MCV, Richmond, VA, USA
| | - Todd WB Gehr
- Department of Internal Medicine, VCU/MCV, Richmond, VA, USA
| | - Marcus E Carr
- Department of Internal Medicine, VCU/MCV, Richmond, VA, USA
- Coagulation Special Studies Laboratory, VCU/MCV, Richmond, VA, USA
- Department of Pathology, VCU/MCV, Richmond, VA, USA
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11
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Brophy DF, Martin EJ, Best AM, Gehr TWB, Carr ME. Antifactor Xa activity correlates to thrombin generation time, platelet contractile force and clot elastic modulus following ex vivo enoxaparin exposure in patients with and without renal dysfunction. J Thromb Haemost 2004; 2:1299-304. [PMID: 15304034 DOI: 10.1111/j.1538-7836.2004.00789.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Antifactor Xa activity is the gold standard monitoring parameter for low molecular weight heparin (LMWH) derivatives. It is frequently measured in high-risk populations, such as patients with renal dysfunction. Despite antifactor Xa monitoring, however, bleeding in renal dysfunction patients receiving LMWH remains a problem. This study determined the relationship between antifactor Xa activity and three novel coagulation monitoring parameters: thrombin generation time (TGT), platelet contractile force (PCF) and clot elastic modulus (CEM). This study also assessed the effect of renal dysfunction on these relationships. This was an ex vivo pharmacodynamic study of the relationship between antifactor Xa activity and TGT, PCF and CEM in subjects both with and without renal dysfunction. Thirty subjects completed this study (10 controls, 10 chronic kidney disease subjects, and 10 end-stage renal disease subjects receiving hemodialysis). Blood samples obtained from participants were spiked with increasing enoxaparin concentrations (0.25, 0.5, 1.0 and 3.0 IU mL(-1)). Samples were analyzed for TGT, PCF and CEM. The relationship between antifactor Xa activity and TGT, PCF and CEM was determined by Pearson's correlation. The effect of renal dysfunction on the relationship between antifactor Xa activity and TGT, PCF and CEM was determined by analysis of covariance. There is strong correlation between antifactor Xa activity and TGT, CEM and PCF. The presence of renal dysfunction significantly prolongs the TGT, and decreases the CEM relative to controls. These results suggest that patients with renal dysfunction have a greater pharmacodynamic response to LMWH, independent of the pharmacokinetics of LMWH.
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Affiliation(s)
- D F Brophy
- Department of Pharmacy, Virginia Commonwealth University, Medical College of Virginia Campus, Richmond, Virginia, USA.
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12
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Brophy DF, Martin EJ, Gehr TWB, Carr ME. Enhanced anticoagulant activity of enoxaparin in patients with ESRD as measured by thrombin generation time. Am J Kidney Dis 2004; 44:270-7. [PMID: 15264185 DOI: 10.1053/j.ajkd.2004.04.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Patients with renal dysfunction who undergo systemic anticoagulation with enoxaparin are at increased risk for bleeding. Although there is decreased renal clearance of enoxaparin in this population, the clinical utility of monitoring antifactor Xa activity is controversial because it is weakly correlated to bleeding. The goal of this study was to investigate the role of other novel anticoagulation markers, such as thrombin generation time, platelet contractile force, and clot elastic modulus, while controlling for antifactor Xa activity in patients with and without renal dysfunction. METHODS Thirty anticoagulant- and antiplatelet-naive subjects completed this trial (10 controls, 10 patients with chronic kidney disease, and 10 patients with end-stage renal disease [ESRD]). Blood samples were obtained and spiked ex vivo with increasing concentrations of enoxaparin antifactor Xa activity (0.25, 0.5, 1.0, and 3.0 IU/mL). Thrombin generation time, platelet contractile force, and clot elastic modulus were measured in each group at each antifactor Xa activity concentration. RESULTS Subjects with ESRD had an approximately 50% greater anticoagulant effect, determined by thrombin generation time prolongation, than controls at antifactor Xa activity concentrations of 0.5 to 3.0 IU/mL. This may explain why subjects with ESRD with seemingly therapeutic antifactor Xa levels still experience adverse bleeding. There were no intergroup differences in platelet function, determined by platelet contractile force and clot elastic modulus. CONCLUSION Antifactor Xa poorly predicts the degree of anticoagulation in patients with ESRD administered low-molecular-weight heparin (LMWH). Thrombin generation time may be a clinically useful anticoagulation monitoring tool to monitor LMWH therapy, especially in patients with renal dysfunction. Additional randomized prospective studies are needed to corroborate these findings.
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Affiliation(s)
- Donald F Brophy
- Department of Pharmacy Practice, Virginia Commonwealth University/Medical College of Virginia, Richmond, VA, USA.
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13
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Current literature in diabetes. Diabetes Metab Res Rev 2003; 19:76-83. [PMID: 12592647 DOI: 10.1002/dmrr.346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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14
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Carr ME, Carr SL, Roa V, McCardell KA, Greilich PE. Aprotinin counteracts heparin-induced inhibition of platelet contractile force. Thromb Res 2002; 108:161-8. [PMID: 12590953 DOI: 10.1016/s0049-3848(02)00403-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Aprotinin interferes with heparin binding to platelets and decreases blood loss during cardiopulmonary bypass (CPB). Heparin abolishes platelet force during CPB, and the extent of platelet force recovery after protamine administration appears to correlate with blood loss. This study assessed the effect of aprotinin on heparin suppression of platelet force. METHODS Platelet force was measured using the Hemodyne Hemostasis Analyzer. Clots were formed from platelet-rich plasma (PRP) by the addition of batroxobin and 10 mM CaCl(2). Clotting conditions included pH 7.4, ionic strength 0.15 M, fibrinogen level 1 mg/ml and 75,000 platelets/microl. RESULTS After 1200 s of clotting, force was reduced from 7110+/-1190 to 450+/-450 dyn by 0.2 U/ml of heparin. Platelet force in aprotinin [20 microg/ml (140 KIU/ml)] containing PRP was not suppressed by heparin addition (7480+/-2410 dyn). Aprotinin [40 microg/ml (280 KIU/ml)] addition to previously heparinized plasma counteracted heparin force suppression. Aprotinin (40 microg/ml) increased platelet force from 5630 to 11,138+/-562 in PRP devoid of heparin. Aprotinin did not affect thrombin activity, fibrin structure, platelet aggregation or secretion. CONCLUSIONS Aprotinin counteracts heparin suppression of platelet force and enhances platelet force in the absence of heparin. Aprotinin-heparin-platelet interactions may help explain aprotinin's ability to reduce blood loss during CPB.
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Affiliation(s)
- Marcus E Carr
- Department of Internal Medicine, Medical College of Virginia, Virginia Commonwealth University, Richmond, 23298, USA.
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