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Sample records for reduces thrombus size

  1. Performance of a thrombectomy device for aspiration of thrombus with various sizes based on a computational fluid dynamic modeling.

    PubMed

    Soleimani, Sajjad; Dubini, Gabriele; Pennati, Giancarlo

    2016-06-01

    It is important to thoroughly remove the thrombus within the course of aspiration thrombectomy; otherwise, it may lead to further embolization. The performance of the aspiration thrombectomy device with a generic geometry is studied through the computational approach. In order to model the thrombus aspiration, a real left coronary artery is chosen while thrombi with various sizes are located at the bifurcation area of the coronary artery and, depending on the size of the thrombus, it is stretched toward the side branches. The thrombus occupies the artery resembling the blood current obstruction in the coronary vessel similar to the situation that leads to heart attack. It is concluded that the aspiration ability of the thrombectomy device is not linked to the thrombus size; it is rather linked to the aspiration pressure and thrombus age (organized versus fresh thrombus). However, the aspiration time period correlates to the thrombus size. The minimum applicable aspiration pressure is also investigated in this study. PMID:26351782

  2. Pentamethylquercetin (PMQ) reduces thrombus formation by inhibiting platelet function

    PubMed Central

    Liang, Ming-Lu; Da, Xing-Wen; He, Ao-Di; Yao, Guang-Qiang; Xie, Wen; Liu, Gang; Xiang, Ji-Zhou; Ming, Zhang-Yin

    2015-01-01

    Flavonoids exert both anti-oxidant and anti-platelet activities in vitro and in vivo. Pentamethylquercetin (PMQ), a polymethoxylated flavone derivative, has been screened for anti-carcinogenic and cardioprotective effects. However, it is unclear whether PMQ has anti-thrombotic effects. In the present study, PMQ (20 mg/kg) significantly inhibited thrombus formation in the collagen- epinephrine- induced acute pulmonary thrombosis mouse model and the ferric chloride-induced carotid injury model. To explore the mechanism, we evaluated the effects of PMQ on platelet function. We found that PMQ inhibited platelet aggregation and granule secretion induced by low dose agonists, including ADP, collagen, thrombin and U46619. Biochemical analysis revealed that PMQ inhibited collagen-, thrombin- and U46619-induced activation of Syk, PLCγ2, Akt, GSK3β and Erk1/2. Therefore, we provide the first report to show that PMQ possesses anti-thrombotic activity in vivo and inhibited platelet function in vitro, suggesting that PMQ may represent a potential therapeutic candidate for the prevention or treatment of thrombotic disorders. PMID:26059557

  3. Bromelain proteases reduce human platelet aggregation in vitro, adhesion to bovine endothelial cells and thrombus formation in rat vessels in vivo.

    PubMed

    Metzig, C; Grabowska, E; Eckert, K; Rehse, K; Maurer, H R

    1999-01-01

    The thiol protease, bromelain, an extract from pineapple stem, was suggested to have antithrombotic and anticoagulant activities in vivo. We studied the effects of bromelain on cell size distribution of isolated human platelets in vitro by Coulter Counter measurements. Preincubation of platelets with bromelain (10 micrograms/mL) completely prevented the thrombin (0.2 U/mL) induced platelet aggregation. Papain was less active in preventing platelet aggregation. In vitro, bromelain (0.1 microgram/mL) reduced the adhesion of bound, thrombin stimulated, fluorescent labeled platelets to bovine aorta endothelial cells. In addition, preincubation of platelets with bromelain, prior to thrombin, activation, reduced the platelet adhesion to the endothelial cells to the low binding value of unstimulated platelets. On the basis of mass concentrations, the proteases papain and trypsin were as effective as bromelain. Using a laser thrombosis model, the in vivo effects of orally and intraveneously applied bromelain on thrombus formation in rat mesenteric vessels were studied. Bromelain, orally applied at 60 mg/kg body weight, inhibited the thrombus formation in a time dependent manner, the maximum being after 2 hours in 11% of arterioles and 6% of venoles. Intravenous application at 30 mg/kg was slightly more active in reducing thrombus formation in arterioles (13%) and venoles (5%), suggesting that orally applied bromelain is biologically active. These results may help to explain some of the clinical effects observed after bromelain treatment in patients with thrombosis and related diseases.

  4. Platelet size and density affect shear-induced thrombus formation in tortuous arterioles

    NASA Astrophysics Data System (ADS)

    Chesnutt, Jennifer K. W.; Han, Hai-Chao

    2013-10-01

    Thrombosis accounts for 80% of deaths in patients with diabetes mellitus. Diabetic patients demonstrate tortuous microvessels and larger than normal platelets. Large platelets are associated with increased platelet activation and thrombosis, but the physical effects of large platelets in the microscale processes of thrombus formation are not clear. Therefore, the objective of this study was to determine the physical effects of mean platelet volume (MPV), mean platelet density (MPD) and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A computational model of the transport, shear-induced activation, collision, adhesion and aggregation of individual platelets was used to simulate platelet interactions and thrombus formation in tortuous arterioles. Our results showed that an increase in MPV resulted in a larger number of activated platelets, though MPD and level of tortuosity made little difference on platelet activation. Platelets with normal MPD yielded the lowest amount of mural thrombus. With platelets of normal MPD, the amount of mural thrombus decreased with increasing level of tortuosity but did not have a simple monotonic relationship with MPV. The physical mechanisms associated with MPV, MPD and arteriole tortuosity play important roles in platelet activation and thrombus formation.

  5. Methylglyoxal induces platelet hyperaggregation and reduces thrombus stability by activating PKC and inhibiting PI3K/Akt pathway.

    PubMed

    Hadas, Karin; Randriamboavonjy, Voahanginirina; Elgheznawy, Amro; Mann, Alexander; Fleming, Ingrid

    2013-01-01

    Diabetes is characterized by a dysregulation of glucose homeostasis and platelets from patients with diabetes are known to be hyper-reactive and contribute to the accelerated development of vascular diseases. Since many of the deleterious effects of glucose have been attributed to its metabolite methylgyloxal (MG) rather than to hyperglycemia itself, the aim of the present study was to characterize the effects of MG on platelet function. Washed human platelets were pre-incubated for 15 min with MG and platelet aggregation, adhesion on matrix-coated slides and signaling (Western blot) were assessed ex vivo. In vivo, the effect of MG on thrombus formation was determined using the FeCl3-induced carotid artery injury model. MG potentiated thrombin-induced platelet aggregation and dense granule release, but inhibited platelet spreading on fibronectin and collagen. In vivo, MG accelerated thrombus formation but decreased thrombus stability. At the molecular level, MG increased intracellular Ca(2+) and activated classical PKCs at the same time as inhibiting PI3K/Akt and the β3-integrin outside-in signaling. In conclusion, these findings indicate that the enhanced MG concentration measured in diabetic patients can directly contribute to the platelet dysfunction associated with diabetes characterized by hyperaggregability and reduced thrombus stability.

  6. Nanoliposomal Growth Hormone and Sodium Nitrite Release from Silicone Fibers Reduces Thrombus Formation Under Flow.

    PubMed

    Salehi-Nik, Nasim; Amoabediny, Ghassem; Banikarimi, Seyedeh Parnian; Pouran, Behdad; Malaie-Balasi, Zahra; Zandieh-Doulabi, Behrouz; Klein-Nulend, Jenneke

    2016-08-01

    Biocompatibility of artificial lungs can be improved by endothelialization of hollow fibers. Bioavailability of growth-inducing and anti-thrombotic agents on the hollow fiber-blood interface inhibits thrombosis. We investigated if nanoliposomal growth-inducing growth hormone (nGH) and anti-thrombotic sodium nitrite (nNitrite) incorporation into collagen-coating on silicone hollow fibers improves blood biocompatibility by increasing endothelial cell growth and nitrite bioavailability under flow. Nitrite production rate was assessed under varying flow conditions. Finite element (FE) modeling was used to simulate nitrite transport within the parallel-plate flow chamber, and nitrite bioavailability on the fiber-blood interface at 1-30 dyn/cm(2) shear stress. Endothelial cell number on fibers coated with nNitrite-nGH-collagen conjugate was 1.5-fold higher than on collagen-coated fibers. For collagen-coated fibers, nitrite production reached a maximum at 18 dyn/cm(2) shear stress. When fibers were coated with nNitrite-nGH-collagen conjugate, nitrite production increased continuously by increasing shear stress. FE modeling revealed that nitrite concentrations at the fiber-blood interface were affected by shear stress-induced nitrite production, and diffusion/convection-induced nitrite removal. Highest nitrite concentrations and lowest thrombus deposition were observed on fibers coated with nNitrite-nGH-collagen conjugate exposed to 6-12 dyn/cm(2) shear stress. In conclusion, our results suggest that nNitrite-nGH-Col conjugate coatings promote endothelialization of silicone hollow fibers in biohybrid artificial lungs.

  7. Surface passivation by human albumin of plasmapheresis circuits reduces platelet accumulation and thrombus formation. Experimental and clinical studies.

    PubMed

    Mulvihill, J N; Faradji, A; Oberling, F; Cazenave, J P

    1990-02-01

    The contact of flowing blood with an artificial surface leads to adsorption of plasma proteins, followed by platelet adhesion and aggregation and thrombus formation. This phenomenon is enhanced by turbulent flow at joints, bifurcations, and constrictions. In therapeutic plasmapheresis using an IBM blood cell separator, blockage of the extracorporeal circulation system by platelet-fibrin thrombi imposed a halt in treatment for manual clearance of the circuit for 66 in 149 cases (44%). Thus it was decided to passivate the surface of the extracorporeal circuit by filling the tubing with 4% human serum albumin 15-20 min before the treatment session and then displacing the albumin solution with the patient's blood without creating an air-liquid interface. After introduction of this technique, a blockage was observed for only 11 in 239 cases (5%). In vitro measurements of platelet accumulation on the internal surface of the circulation system were carried out using washed human platelets labeled with 111In-oxine in the presence of a 40% hematocrit. Preadsorption of the surface with albumin reduced platelet deposition to 4-5% that observed for an equivalent pretreatment with physiological saline. PMID:2329112

  8. Direct Thrombus Imaging in Stroke

    PubMed Central

    Kim, Jongseong; Park, Jung E.; Nahrendorf, Matthias; Kim, Dong-Eog

    2016-01-01

    There is an emergent need for imaging methods to better triage patients with acute stroke for tissue-plasminogen activator (tPA)-mediated thrombolysis or endovascular clot retrieval by directly visualizing the size and distribution of cerebral thromboemboli. Currently, magnetic resonance (MR) or computed tomography (CT) angiography visualizes the obstruction of blood flow within the vessel lumen rather than the thrombus itself. The present visualization method, which relies on observation of the dense artery sign (the appearance of cerebral thrombi on a non-enhanced CT), suffers from low sensitivity. When translated into the clinical setting, direct thrombus imaging is likely to enable individualized acute stroke therapy by allowing clinicians to detect the thrombus with high sensitivity, assess the size and nature of the thrombus more precisely, serially monitor the therapeutic effects of thrombolysis, and detect post-treatment recurrence. This review is intended to provide recent updates on stroke-related direct thrombus imaging using MR imaging, positron emission tomography, or CT. PMID:27733029

  9. Reducing Class Size To Increase Student Involvement.

    ERIC Educational Resources Information Center

    Lottes, Christine R.

    Reducing class size was considered an important element in a revised health course at Gettysburg College (Pennsylvania). However, reducing class size to approximately 15 students per class would require 38 sections, more than the health faculty could handle. To recruit additional instructors, the course was marketed to faculty and administrators…

  10. Clinical Sequelae of Thrombus in an Inferior Vena Cava Filter

    SciTech Connect

    Ahmad, Iftikhar; Yeddula, Kalpana; Wicky, Stephan; Kalva, Sanjeeva P.

    2010-04-15

    The purpose of this study was to assess the long-term clinical sequelae of inferior vena cava (IVC) filter thrombus and the effect of anticoagulation on filter thrombus. Of 1,718 patients who had IVC filters placed during 2001-2008, 598 (34.8%) had follow-up abdominal CT. Filter thrombus was seen in 111 of the 598 (18.6%). There were 44 men (39.6%). The mean age at filter placement was 64 years. The medical diseases included cancer in 64, trauma in 15, stroke in 12, and others in 20. The frequency of filter thrombus on CT and asymptomatic filter thrombus on CT was calculated. The frequency of pulmonary embolism (PE) in patients with filter thrombus was calculated. The frequency of thrombus progression or regression (on CT, available in 56) was calculated. The effect of anticoagulation on filter thrombus regression/progression was evaluated using the Fisher exact test by comparing the group of patients who received anticoagulants versus those who did not. A P-value of <0.05 was considered significant. The overall frequency of filter thrombus was 18.6%. Total occlusion of the IVC filter was seen in 12 of 598 (2%). The filter thrombus was asymptomatic in 110 (18.3%). Filter thrombus was detected after a median of 35 days (range, 0-2082) following filter placement. Thrombus extended above the filter in 4 (3.6%); IVC thrombus below the filter was seen in 35(31.5%). Thrombus in the filter occluded <25% of the filter volume in 58 (52.3%), 25-50% in 21 (18.9%), and 50-75% in 20 (18%). Total IVC occlusion was seen in 12 (10.8%). Eighty-three patients received anticoagulation. Sixteen patients developed symptoms of PE. PE was confirmed on CT in 3 of 15 (2.7%). On follow-up, filter thrombus regressed completely in 19 (33.9%) after a median of 6 months. Filter thrombus decreased in size in 13 (23.2%) and it progressed without IVC occlusion in 7 (12.6%). In one (1.7%), filter thrombus progressed to IVC occlusion. Filter thrombus remained stable in 16 (28.6%). There was no

  11. The fluid mechanics of thrombus formation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Experimental data are presented for the growth of thrombi (blood clots) in a stagnation point flow of fresh blood. Thrombus shape, size and structure are shown to depend on local flow conditions. The evolution of a thrombus is described in terms of a physical model that includes platelet diffusion, a platelet aggregation mechanism, and diffusion and convection of the chemical species responsible for aggregation. Diffusion-controlled and convection-controlled regimes are defined by flow parameters and thrombus location, and the characteristic growth pattern in each regime is explained. Quantitative comparisons with an approximate theoretical model are presented, and a more general model is formulated.

  12. Reducing Class Size: Promises and Perils

    ERIC Educational Resources Information Center

    Bascia, Nina; Fredua-Kwarteng, Eric

    2008-01-01

    Reducing class size, especially in primary grades, can have tremendous academic and social benefits for children--benefits that endure well beyond those first years of school. But smaller class sizes are not a cure-all. Beyond the hoopla of enthusiasm for this seemingly simple change in educational practice lie serious consequences for students…

  13. Effect of Red Blood Cells on Platelet Activation and Thrombus Formation in Tortuous Arterioles

    PubMed Central

    Chesnutt, Jennifer K. W.; Han, Hai-Chao

    2013-01-01

    Thrombosis is a major contributor to cardiovascular disease, which can lead to myocardial infarction and stroke. Thrombosis may form in tortuous microvessels, which are often seen throughout the human body, but the microscale mechanisms and processes are not well understood. In straight vessels, the presence of red blood cells (RBCs) is known to push platelets toward walls, which may affect platelet aggregation and thrombus formation. However in tortuous vessels, the effects of RBC interactions with platelets in thrombosis are largely unknown. Accordingly, the objective of this work was to determine the physical effects of RBCs, platelet size, and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A discrete element computational model was used to simulate the transport, collision, adhesion, aggregation, and shear-induced platelet activation of hundreds of individual platelets and RBCs in thrombus formation in tortuous arterioles. Results showed that high shear stress near the inner sides of curved arteriole walls activated platelets to initiate thrombosis. RBCs initially promoted platelet activation, but then collisions of RBCs with mural thrombi reduced the amount of mural thrombus and the size of emboli. In the absence of RBCs, mural thrombus mass was smaller in a highly tortuous arteriole compared to a less tortuous arteriole. In the presence of RBCs however, mural thrombus mass was larger in the highly tortuous arteriole compared to the less tortuous arteriole. As well, smaller platelet size yielded less mural thrombus mass and smaller emboli, either with or without RBCs. This study shed light on microscopic interactions of RBCs and platelets in tortuous microvessels, which have implications in various pathologies associated with thrombosis and bleeding. PMID:25022613

  14. Phenylthiourea specifically reduces zebrafish eye size.

    PubMed

    Li, Zeran; Ptak, Devon; Zhang, Liyun; Walls, Elwood K; Zhong, Wenxuan; Leung, Yuk Fai

    2012-01-01

    Phenylthiourea (PTU) is commonly used for inhibiting melanization of zebrafish embryos. In this study, the standard treatment with 0.2 mM PTU was demonstrated to specifically reduce eye size in larval fish starting at three days post-fertilization. This effect is likely the result of a reduction in retinal and lens size of PTU-treated eyes and is not related to melanization inhibition. This is because the eye size of tyr, a genetic mutant of tyrosinase whose activity is inhibited in PTU treatment, was not reduced. As PTU contains a thiocarbamide group which is presented in many goitrogens, suppressing thyroid hormone production is a possible mechanism by which PTU treatment may reduce eye size. Despite the fact that thyroxine level was found to be reduced in PTU-treated larvae, thyroid hormone supplements did not rescue the eye size reduction. Instead, treating embryos with six goitrogens, including inhibitors of thyroid peroxidase (TPO) and sodium-iodide symporter (NIS), suggested an alternative possibility. Specifically, three TPO inhibitors, including those that do not possess thiocarbamide, specifically reduced eye size; whereas none of the NIS inhibitors could elicit this effect. These observations indicate that TPO inhibition rather than a general suppression of thyroid hormone synthesis is likely the underlying cause of PTU-induced eye size reduction. Furthermore, the tissue-specific effect of PTU treatment might be mediated by an eye-specific TPO expression. Compared with treatment with other tyrosinase inhibitors or bleaching to remove melanization, PTU treatment remains the most effective approach. Thus, one should use caution when interpreting results that are obtained from PTU-treated embryos.

  15. Reducing Class Size Leads to Individualized Instruction.

    ERIC Educational Resources Information Center

    Zahorik, John A.

    1999-01-01

    SAGE is a five-year class-size-reduction program being implemented in 80 Wisconsin schools. A longitudinal, evaluative study is being conducted in 30 SAGE schools. Small classes have three effects leading to increased individualization: fewer discipline problems, greater knowledge of students, and more teacher enthusiasm (using directive methods).…

  16. Hydroxyethyl starch increases patency and reduces thrombus formation following arteriotomy/intimectomy in small arteries: An experimental study in the rabbit

    SciTech Connect

    Wieslander, J.B.; Salemark, L.; Dougan, P. )

    1990-10-01

    Twenty-four arteries of rabbit ears, divided into two groups of 12 vessels each, were prepared and {sup 32}P-labelled platelets were infused. Arteriotomy/intimectomy was performed after 1 hr and in vivo platelet accumulation recorded for 2 hr. Group A comprised untreated control animals and group B was treated with 1 g hydroxyethyl starch (HES), MW 450,000 in 17 ml saline/kg b.w. (Plasma-steril). Vessel bleeding-times were normal, patency was improved, and intraluminal thrombotic material was reduced after HES treatment. Initial in vivo platelet accumulation was rapid and reached similar levels in both groups. However, the platelet accumulation curves decreased more frequently following HES than in the control group. HES does not prevent platelet accumulation at trauma sites, but reduces the sizes of the thrombi formed and may enhance disaggregation/fibrinolysis.

  17. Thrombus aspiration catheter is a Dottering balloon.

    PubMed

    Sheshagiri Rao, D; Barik, Ramachandra; Prasad, Akula Siva

    2016-01-01

    Coronary angiogram in a young man with history of STEMI with delayed presentation revealed subtotal occlusion of left anterior descending artery (LAD) with large thrombotic filling defect distal to the critical lesion. PCI was preferred without delay because of ongoing chest pain. Several runs of thrombus aspiration failed to detect any visible thrombus. However, the immediate angiogram after thrombus aspiration showed complete distal embolization of the thrombus which could have been achieved by Dottering or balloon dilatation. In contrary to the general perception, does thrombus aspiration push more thrombus than it can aspirate? PMID:27543477

  18. Thrombus aspiration in ST-segment elevation myocardial infarction.

    PubMed

    Meneguz-Moreno, R A; Costa, R A; A, A; Ribamar Costa, J; Abizaid, A

    2015-12-01

    Primary percutaneous coronary intervention (PCI) has become the treatment of choice in patients with ST-segment elevation myocardial infarction (STEMI) throughout the last years. A significant number of studies have demonstrated a morbidity and mortality benefit over thrombolysis, which has been attributed to better coronary perfusion in patients undergoing primary PCI. Even though it usually achieves normal flow in the affected epicardial vessel, myocardial reperfusion is not fully restored in a significant percentage of patients. This is commonly the result of distal thrombus embolization with subsequent impairment of myocardial microcirculation. Recognition of this has led to the development of a number of devices with different mechanisms, including thrombus aspiration catheters, in order to reduce distal embolization and therefore improve myocardial perfusion. Recent studies indeed demonstrate that the use of such devices offer additional clinical advantage in patients undergoing primary PCI in comparison to the standard PCI, whether in other trials it could not be proved. This paper focuses on general mechanisms of thrombus formation and discusses favorable and unfavorable studies towards thrombus aspiration in STEMI and its main aspects and it comes up with specific subjects that could benefit or not from the procedure of thrombus aspiration. PMID:26603617

  19. Visual Space: Adaptation to Texture Density Reduces Perceived Object Size.

    PubMed

    Kingdom, Frederick A A

    2016-07-25

    A recent study shows that visual adaptation to dense textures, while causing an increase in the perceived sparseness of a subsequently viewed less-dense texture, paradoxically reduces the perceived size of an object, revealing a dissociation between the internal spatial representations of textures and objects.

  20. Thrombus aspiration in acute myocardial infarction: concepts, clinical trials, and current guidelines.

    PubMed

    Vandermolen, Sebastian; Marciniak, Maciej; Byrne, Jonathan; De Silva, Kalpa

    2016-05-01

    The pathogenesis that underlies acute myocardial infarction is complex and multifactorial. One of the most important components, however, is the role of thrombus formation following atherosclerotic plaque rupture, leading to sudden coronary occlusion and subsequent ischemia and infarction. Thrombus aspiration provides the opportunity of intracoronary clot extraction with the aim to improve coronary and myocardial perfusion, by reducing the risk of no-reflow secondary to distal embolization of thrombus. The utility of thrombus aspiration during primary percutaneous coronary intervention has been assessed in an increasing number of observational and randomized studies. This article reviews the contemporary data and provides insights into the validity of thrombus aspiration in the setting of acute myocardial infarction. PMID:26751424

  1. Clinical and histopathological effects of presurgical treatment with sunitinib for renal cell carcinoma with inferior vena cava tumor thrombus at a single institution

    PubMed Central

    Ujike, Takeshi; Kawashima, Atsunari; Nagahara, Akira; Fujita, Kazutoshi; Miyagawa, Yasushi; Nonomura, Norio

    2016-01-01

    To evaluate the clinical and histopathological effects of presurgical treatment with sunitinib on inferior vena cava (IVC) tumor thrombus. Between 2010 and 2014, we treated seven patients with renal cell carcinoma and IVC tumor thrombus presurgically with sunitinib. We retrospectively evaluated primitive tumor size, the level of tumor thrombus according to Novick’s classification, its distance above the renal vein, thrombus diameter at its widest segment, and histopathological change after sunitinib treatment. Three patients were diagnosed histologically. Percutaneous biopsy of the renal mass before sunitinib treatment was performed in two patients. One patient was diagnosed after sunitinib treatment following nephrectomy. The primitive tumors shrank upon sunitinib therapy in four cases; however, although the caval thrombus was downstaged (from level II to I) in one patient, the level of caval thrombus did not change in five patients and increased in one patient (from level III to IV). We evaluated the histopathological effects in two patients. In one patient, the IVC tumor thrombus was mostly replaced with necrotic tissue, but its thrombus level was not downstaged. In the other patient, the IVC tumor thrombus was downstaged, but tumor thrombus was not replaced with necrotic tissue and viable tumor cells remained. Presurgical treatment with sunitinib for renal cell carcinoma with IVC tumor thrombus appears to have limited effect on IVC tumor thrombus, in contrast to its effects on primitive tumor shrinkage. In the absence of evidence of presurgical benefits from prospective studies, this treatment may not be systematically advisable. PMID:27557138

  2. Reducing myocardial infarct size: challenges and future opportunities.

    PubMed

    Bulluck, Heerajnarain; Yellon, Derek M; Hausenloy, Derek J

    2016-03-01

    Despite prompt reperfusion by primary percutaneous coronary intervention (PPCI), the mortality and morbidity of patients presenting with an acute ST-segment elevation myocardial infarction (STEMI) remain significant with 9% death and 10% heart failure at 1 year. In these patients, one important neglected therapeutic target is 'myocardial reperfusion injury', a term given to the cardiomyocyte death and microvascular dysfunction which occurs on reperfusing ischaemic myocardium. A number of cardioprotective therapies (both mechanical and pharmacological), which are known to target myocardial reperfusion injury, have been shown to reduce myocardial infarct (MI) size in small proof-of-concept clinical studies-however, being able to demonstrate improved clinical outcomes has been elusive. In this article, we review the challenges facing clinical cardioprotection research, and highlight future therapies for reducing MI size and preventing heart failure in patients presenting with STEMI at risk of myocardial reperfusion injury.

  3. Reducing myocardial infarct size: challenges and future opportunities

    PubMed Central

    Bulluck, Heerajnarain; Yellon, Derek M; Hausenloy, Derek J

    2016-01-01

    Despite prompt reperfusion by primary percutaneous coronary intervention (PPCI), the mortality and morbidity of patients presenting with an acute ST-segment elevation myocardial infarction (STEMI) remain significant with 9% death and 10% heart failure at 1 year. In these patients, one important neglected therapeutic target is ‘myocardial reperfusion injury’, a term given to the cardiomyocyte death and microvascular dysfunction which occurs on reperfusing ischaemic myocardium. A number of cardioprotective therapies (both mechanical and pharmacological), which are known to target myocardial reperfusion injury, have been shown to reduce myocardial infarct (MI) size in small proof-of-concept clinical studies—however, being able to demonstrate improved clinical outcomes has been elusive. In this article, we review the challenges facing clinical cardioprotection research, and highlight future therapies for reducing MI size and preventing heart failure in patients presenting with STEMI at risk of myocardial reperfusion injury. PMID:26674987

  4. Platelet transport rates and binding kinetics at high shear over a thrombus.

    PubMed

    Bark, David L; Ku, David N

    2013-07-16

    Thrombus formation over a ruptured atherosclerotic plaque cap can occlude an artery with fatal consequences. We describe a computational model of platelet transport and binding to interpret rate-limiting steps seen in experimental thrombus formation over a collagen-coated stenosis. The model is used to compute shear rates in stenoses with growing boundaries. In the model, moving erythrocytes influence platelet transport based on shear-dependent enhanced diffusivity and a nonuniform platelet distribution. Adhesion is modeled as platelet-platelet binding kinetics. The results indicate that observed thrombus growth rates are limited by platelet transport to the wall for shear rates up to 6000 s(-1). Above 7000 s(-1), the thrombus growth rate is likely limited by binding kinetics (10(-4) m/s). Thrombus growth computed from these rate-limiting steps match the thrombus location and occlusion times for experimental conditions if a lag time for platelet activation is included. Using fitted parameters, the model is then used to predict thrombus size and shape at a higher Reynolds number flow consistent with coronary artery disease. PMID:23870271

  5. Platelet Transport Rates and Binding Kinetics at High Shear over a Thrombus

    PubMed Central

    Bark, David L.; Ku, David N.

    2013-01-01

    Thrombus formation over a ruptured atherosclerotic plaque cap can occlude an artery with fatal consequences. We describe a computational model of platelet transport and binding to interpret rate-limiting steps seen in experimental thrombus formation over a collagen-coated stenosis. The model is used to compute shear rates in stenoses with growing boundaries. In the model, moving erythrocytes influence platelet transport based on shear-dependent enhanced diffusivity and a nonuniform platelet distribution. Adhesion is modeled as platelet-platelet binding kinetics. The results indicate that observed thrombus growth rates are limited by platelet transport to the wall for shear rates up to 6000 s−1. Above 7000 s−1, the thrombus growth rate is likely limited by binding kinetics (10−4 m/s). Thrombus growth computed from these rate-limiting steps match the thrombus location and occlusion times for experimental conditions if a lag time for platelet activation is included. Using fitted parameters, the model is then used to predict thrombus size and shape at a higher Reynolds number flow consistent with coronary artery disease. PMID:23870271

  6. Novel Trial Designs: Lessons Learned from Thrombus Aspiration During ST-Segment Elevation Myocardial Infarction in Scandinavia (TASTE) Trial.

    PubMed

    Wachtell, Kristian; Lagerqvist, Bo; Olivecrona, Göran K; James, Stefan K; Fröbert, Ole

    2016-01-01

    In ST-elevation myocardial infarction (STEMI), thrombus material is often present in partial or total coronary occlusion of the coronary vessel. However, prior to the thrombus aspiration during ST-Segment Elevation Myocardial Infarction in Scandinavia (TASTE) trial, it remained unclear whether routine thrombus aspiration during percutaneous coronary intervention (PCI) treatment of STEMI would result in patients overall survival benefit. The TASTE trial was a multicenter, prospective, open-label, randomized, controlled clinical trial. In order to randomize patients to treatment and collect data, the infrastructure of a clinical population-based registry was used. Online data collection used the national comprehensive Swedish Coronary Angiography and Angioplasty Registry, a part of the SWEDEHEART registry. Monitoring and adjudication was done as part of the regular registry validation. There was no separate, dedicated monitoring or adjudication of endpoints. Included were 7244 patients with STEMI with chest pain and time of symptoms to hospital admission <24 h, in addition to new electrocardiographic ST-segment elevation or left bundle-branch block. Exclusion criteria were the need for emergency coronary artery bypass grafting. All-cause mortality at 30 days occurred in 2.8 % of the patients in the thrombus-aspiration group, as compared with 3.0 % in the PCI-only group (hazard ratio [HR] 0.94, 95 % confidence interval [CI] 0.72-1.22; p = 0.63). All-cause mortality at 1 year occurred in 5.3 % of the patients in the thrombus-aspiration group, as compared with 5.6 % in the PCI-only group (HR 0.94, 95 % CI 0.78-1.15; p = 0.57). No patients were lost to follow-up at 1 year. The incremental cost for trial execution was approximately US$ 300,000 or $50 per patient. Routine thrombus aspiration during PCI in patients with STEMI did not reduce the rate of all-cause mortality at 1 year. It is possible to design and conduct mega-trial at only small cost compared to a

  7. Tunable Reduced Size Planar Folded Slot Antenna Utilizing Varactor Diodes

    NASA Technical Reports Server (NTRS)

    Scardelletti, Maximilian C.; Ponchak, George E.; Jordan, Jennifer L.; Jastram, Nathan; Mahaffey, Joshua V.

    2010-01-01

    A tunable folded slot antenna that utilizes varactor diodes is presented. The antenna is fabricated on Rogers 6006 Duriod with a dielectric constant and thickness of 6.15 and 635 m, respectively. A copper cladding layer of 17 m defines the antenna on the top side (no ground on backside). The antenna is fed with a CPW 50 (Omega) feed line, has a center frequency of 3 GHz, and incorporates Micrometrics microwave hyper-abrupt 500MHV varactors to tune the resonant frequency. The varactors have a capacitance range of 2.52 pF at 0 V to 0.4 pF at 20 V; they are placed across the radiating slot of the antenna. The tunable 10 dB bandwidth of the 3 GHz antenna is 150 MHz. The varactors also reduce the size of the antenna by 30% by capacitively loading the resonating slot line. At the center frequency, 3 GHz, the antenna has a measured return loss of 44 dB and a gain of 1.6 dBi. Full-wave electromagnetic simulations using HFSS are presented that validate the measured data. Index Terms capacitive loading, Duriod, folded slot antenna, varactor.

  8. Recanalization and flow regulate venous thrombus resolution and Matrix metalloproteinases expression in vivo

    PubMed Central

    Chabasse, Christine; Siefert, Suzanne A.; Chaudry, Mohammed; Hoofnagle, Mark H.; Lal, Brajesh K.; Sarkar, Rajabrata

    2016-01-01

    Objective We examined the role of thrombus recanalization and ongoing blood flow in the process of thrombus resolution by comparing two murine in vivo models of deep venous thrombosis. Design of study In CD1 mice, we performed surgical inferior vena cava (IVC) ligation (stasis thrombosis), stenosis (thrombosis with recanalization) or sham procedure. We analyzed thrombus weight over time as a measure of thrombus resolution, and quantified the mRNA and protein levels of Membrane-Type Matrix Metalloproteinases (MT-MMPs) as well as effectors of the plasmin complex at day 4, 8 and 12 post-surgery. Results Despite similar initial thrombus size, the presence of ongoing blood flow (stenosis model) was associated with a 45.91% subsequent improvement in thrombus resolution at day 8, and 12.57% at day 12, as compared with stasis thrombosis (ligation model). Immunoblot and real-time PCR demonstrated a difference in MMP-2 and MMP-9 activity at day 8 between the two models (P=.03 and P=.006 respectively), as well as a difference in MT2-MMP gene expression at day 8 (P=.044) and day 12 (P=0.03) and MT1-MMP protein expression at day 4 (P=.021). Histological analyses revealed distinct areas of recanalization in the thrombi of the stenosis model compared to the ligation model, as well as the recruitment of inflammatory cells, especially macrophages, and a focal pattern of localized expression of MT1-MMP and MT3-MMP proteins surrounding the areas of recanalization in the stenosis model. Conclusions Recanalization and ongoing blood flow accelerate deep venous thrombus resolution in vivo, and are associated with distinct patterns of MT1- and MT3-MMP expression and macrophages localization in areas of intra-thrombus recanalization. PMID:26993683

  9. Successful resolution of a left ventricular thrombus with apixaban treatment following acute myocardial infarction.

    PubMed

    Mano, Yoshinori; Koide, Kimi; Sukegawa, Hiroaki; Kodaira, Masaki; Ohki, Takahiro

    2016-01-01

    A 62-year-old man was admitted to our emergency department owing to prolonged chest pain that had lasted for 3 h. An electrocardiogram showed ST elevation in leads I, aVL, and V1-6, and the patient's laboratory revealed elevated myocardial necrosis marker levels. Emergency coronary angiography showed total occlusion of the proximal left anterior descending coronary artery. Subsequent percutaneous coronary intervention was performed by balloon angioplasty followed by stent implantation, and the patient showed improvement. However, echocardiographic examination 2 weeks after the percutaneous coronary intervention showed a thrombus (40 × 14 mm) in the apex of the left ventricle. In addition to dual antiplatelet therapy, apixaban was administered as anticoagulant therapy for the left ventricular thrombus. The size of the thrombus gradually decreased, and magnetic resonance imaging performed approximately 6 weeks after the initial apixaban administration showed no thrombus without a thromboembolic event. This case demonstrates that left ventricular thrombus can be resolved with apixaban treatment. Apixaban may be an effective alternative to vitamin K antagonist for some patients with acute myocardial infarction complicated by left ventricular thrombus.

  10. Effects of vascular constriction on occlusive thrombus formation of rat mesenteric artery.

    PubMed

    Araki, H; Nishi, K

    1986-10-01

    Effects of vascular constriction on thrombotic occlusion was evaluated using rat mesenteric arteries and video-recording system attached to the microscope. Topical application of norepinephrine of 1, 10 and 100 micrograms/ml reduced the arterial diameter dose dependently from 297 +/- 41 mu to 166 +/- 50, 87 +/- 18 and 84 +/- 11 mu (mean +/- SD, n = 7), respectively. The diameter reduction by the higher 2 doses persisted for more than 30 minutes until the wash out of the agent. But, no thrombus formation was observed. A reproducible thrombus formation was induced by inserting a glass micropipette into the vascular lumen. The maximal percent occlusion by the thrombus was 80 +/- 11% (range; 67 to 95%, n = 7). The topical application of 10 micrograms/ml norepinephrine induced vasoconstriction and increased the percent occlusion significantly to 97 +/- 8% (p less than 0.05). Complete occlusion of the lumen developed in 6 of 7 rats after the agent and in 2 rats it was not released until the wash out of the agent for more than 30 minutes. Thrombus formation itself did not change the arterial diameter at the site of thrombus formation as well as at sites of 300 and 600 mu down stream. It is suggested that the vascular constriction alone does not necessarily cause thrombus formation but may aggravate the arterial flow reduction induced by thrombosis.

  11. Reducing Router Forwarding Table Size Using Aggregation and Caching

    ERIC Educational Resources Information Center

    Liu, Yaoqing

    2013-01-01

    The fast growth of global routing table size has been causing concerns that the Forwarding Information Base (FIB) will not be able to fit in existing routers' expensive line-card memory, and upgrades will lead to a higher cost for network operators and customers. FIB Aggregation, a technique that merges multiple FIB entries into one, is probably…

  12. Reduced-size kernel models for nonlinear hybrid system identification.

    PubMed

    Le, Van Luong; Bloch, Grard; Lauer, Fabien

    2011-12-01

    This brief paper focuses on the identification of nonlinear hybrid dynamical systems, i.e., systems switching between multiple nonlinear dynamical behaviors. Thus the aim is to learn an ensemble of submodels from a single set of input-output data in a regression setting with no prior knowledge on the grouping of the data points into similar behaviors. To be able to approximate arbitrary nonlinearities, kernel submodels are considered. However, in order to maintain efficiency when applying the method to large data sets, a preprocessing step is required in order to fix the submodel sizes and limit the number of optimization variables. This brief paper proposes four approaches, respectively inspired by the fixed-size least-squares support vector machines, the feature vector selection method, the kernel principal component regression and a modification of the latter, in order to deal with this issue and build sparse kernel submodels. These are compared in numerical experiments, which show that the proposed approach achieves the simultaneous classification of data points and approximation of the nonlinear behaviors in an efficient and accurate manner.

  13. High Speed Gear Sized and Configured to Reduce Windage Loss

    NASA Technical Reports Server (NTRS)

    Kunz, Robert F. (Inventor); Medvitz, Richard B. (Inventor); Hill, Matthew John (Inventor)

    2013-01-01

    A gear and drive system utilizing the gear include teeth. Each of the teeth has a first side and a second side opposite the first side that extends from a body of the gear. For each tooth of the gear, a first extended portion is attached to the first side of the tooth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates. The gear may be utilized in drive systems that may have high rotational speeds, such as speeds where the tip velocities are greater than or equal to about 68 m/s. Some embodiments of the gear may also utilize teeth that also have second extended portions attached to the second sides of the teeth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates.

  14. Pathophysiology of Coronary Thrombus Formation and Adverse Consequences of Thrombus During PCI

    PubMed Central

    Srikanth, Sundararajan; Ambrose, John A

    2012-01-01

    Atherosclerosis is a systemic vascular pathology that is preceded by endothelial dysfunction. Vascular inflammation “fuels” atherosclerosis and creates the milieu for episodes of intravascular thromboses. Thrombotic events in the coronary vasculature may lead to asymptomatic progression of atherosclerosis or could manifest as acute coronary syndromes or even sudden cardiac death. Thrombus encountered in the setting of acute coronary syndromes has been correlated with acute complications during percutaneous coronary interventions such as no-reflow, acute coronary occlusion and long term complications such as stent thrombus. This article reviews the pathophysiology of coronary thrombogenesis and explores the complications associated with thrombus during coronary interventions. PMID:22920487

  15. Testing new submersible pumps for proper sizing and reduced costs

    SciTech Connect

    O'Toole, W.P.; O'Brien, J.B.

    1986-01-01

    This paper describes an ongoing program to improve overall submersible pump performance by Thums Long Beach Company, acting as Contractor of the City of Long Beach, Operator of the Long Beach Unit. Thums Long Beach Company currently operates 700 submersible pump installations located on four man-made islands and one land fill pier location. The program began with spot testing of submersible pumps for Thums' use. It has evolved to 100 percent pump testing and the stipulation that only pumps with newly manufactured parts are acceptable. The primary goals of this program are to increase well production and lower lifting costs. Critical to these goals is increasing the average length of run by using accurate pump performance data to design equipment and by rejecting defective pumps before they are run. Increased production is realized from better designs. Lower lifting costs result from utilizing higher efficiency pumps and a reduced frequency of pulling submersible equipment.

  16. Testing new submersible pumps for proper sizing and reduced costs

    SciTech Connect

    O'Toole, W.P.; O'Brien, J.B.

    1989-02-01

    This paper describes an ongoing program to improve overall submersible pump performance by Thums Long Beach Co., acting as contractor for the City of Long Beach, operator of the Long Beach Unit. Thums Long Beach Co. currently operates 700 submersible pump installations located on four manmade islands and one landfill pier location. The program began with spot testing of submersible pumps for Thums' use. It has evolved to 100% pump testing and the stipulation that only pumps with newly manufactured parts are acceptable. The primary goals of this program are to increase well production and to lower lifting costs. Critical to these goals is increasing the average length of run by using accurate pump-performance data to design equipment and by rejecting defective pumps before they are run. Increased production is realized from better designs. Lower lifting costs result from using more efficient pumps and a reduced frequency of pulling submersible equipment.

  17. 43 CFR 4300.53 - Can BLM reduce the size of the land in my permit?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; ALASKA; REINDEER; GENERAL Changes in the Size of the Permit Area § 4300.53 Can BLM reduce the size of the... number of reindeer you are grazing; or (b) When disposal, withdrawal, natural causes, such as drought...

  18. 43 CFR 4300.53 - Can BLM reduce the size of the land in my permit?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; ALASKA; REINDEER; GENERAL Changes in the Size of the Permit Area § 4300.53 Can BLM reduce the size of the... number of reindeer you are grazing; or (b) When disposal, withdrawal, natural causes, such as drought...

  19. 43 CFR 4300.53 - Can BLM reduce the size of the land in my permit?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...; ALASKA; REINDEER; GENERAL Changes in the Size of the Permit Area § 4300.53 Can BLM reduce the size of the... number of reindeer you are grazing; or (b) When disposal, withdrawal, natural causes, such as drought...

  20. 43 CFR 4300.53 - Can BLM reduce the size of the land in my permit?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; ALASKA; REINDEER; GENERAL Changes in the Size of the Permit Area § 4300.53 Can BLM reduce the size of the... number of reindeer you are grazing; or (b) When disposal, withdrawal, natural causes, such as drought...

  1. Multifunctional nanoagent for thrombus-targeted fibrinolytic therapy

    PubMed Central

    McCarthy, Jason R.; Sazonova, Irina Y.; Erdem, S. Sibel; Hara, Tetsuya; Thompson, Brian D.; Patel, Purvish; Botnaru, Ion; Lin, Charles P.; Reed, Guy L.; Weissleder, Ralph; Jaffer, Farouc A.

    2011-01-01

    Aims Current thrombolytic therapies rely upon exogenous plasminogen activators (PA) to effectively lyse clots, thereby restoring blood flow and preventing tissue and organ death. Yet, these PAs may also impair normal hemostasis which may lead to life-threatening bleeding, including intracerebral hemorrhage. Thus, the aim of this current study is to develop new thrombus-targeted fibrinolytic agents that harness the multifunctional theranostic capabilities of nanomaterials, potentially allowing for the generation of efficacious thrombolytics while minimizing deleterious side effects. Materials and Methods A thrombus-targeted nano-fibrinolytic agent (CLIO-FXIII-PEG-tPA) was synthesized using a magnetofluorescent crosslinked dextran-coated iron oxide (CLIO) nanoparticle platform that was conjugated to recombinant tissue plasminogen activator (tPA). Thrombus-targeting was achieved by derivatizing the nanoparticle with an activated factor XIII (FXIIIa)-sensitive peptide based on the amino terminus of α2-antiplasmin. Human plasma clot binding ability of the targeted and control agents was assessed by fluorescence reflectance imaging. Next, the in vitro enzymatic activity of the agents was assessed by S2288-based amidolytic activity, and an ELISA D-dimer assay for fibrinolysis. In vivo targeting of the nanoagent was next examined by intravital fluorescence microscopy of murine arterial and venous thrombosis. The fibrinolytic activity of the targeted nanoagent compared to free tPA was then evaluated in vivo in murine pulmonary embolism. Results In vitro, the targeted thrombolytic nanoagent demonstrated binding to fresh frozen plasma (FFP) clots superior to control nanoagents (ANOVA p < 0.05). On a weight (mg) basis, the S2288 amidolytic efficiency of the targeted nanoagent was approximately 15% reduced compared to free tPA. When normalized by S2288-based activity, targeted, control, and free tPA samples demonstrated equivalent in vitro fibrinolytic activity against human

  2. Novel risk predictor for thrombus deposition in abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Nestola, M. G. C.; Gizzi, A.; Cherubini, C.; Filippi, S.; Succi, S.

    2015-10-01

    The identification of the basic mechanisms responsible for cardiovascular diseases stands as one of the most challenging problems in modern medical research including various mechanisms which encompass a broad spectrum of space and time scales. Major implications for clinical practice and pre-emptive medicine rely on the onset and development of intraluminal thrombus in which effective clinical therapies require synthetic risk predictors/indicators capable of informing real-time decision-making protocols. In the present contribution, two novel hemodynamics synthetic indicators, based on a three-band decomposition (TBD) of the shear stress signal, are introduced. Extensive fluid-structure computer simulations of patient-specific scenarios confirm the enhanced risk-prediction capabilities of the TBD indicators. In particular, they permit a quantitative and accurate localization of the most likely thrombus deposition in realistic aortic geometries, where previous indicators would predict healthy operation. The proposed methodology is also shown to provide additional information and discrimination criteria on other factors of major clinical relevance, such as the size of the aneurysm.

  3. Factors influencing acute thrombus formation on carotid artery vascular grafts

    SciTech Connect

    Torem, S.; Schneider, P.A.; Paxton, L.D.; Yasuda, H.; Hanson, S.R.

    1988-10-01

    Scintillation camera imaging of 111Indium-labeled platelets has been used to measure acute thrombus formation on modified expanded Teflon (ePTFE) vascular grafts placed in the carotid arteries of normal baboons. Platelet deposition plateaued over 2 hr postoperatively and occurred primarily at the graft-vessel anastomoses. A positive correlation was found between the circulating platelet count in individual animals and the extent of early platelet thrombus deposition. Unmodified ePTFE grafts accumulated 4.6 +/- 1.2 x 10(9) platelets per graft, or 2.3 +/- 0.71 x 10(9) platelets per anastomosis. Acutely, platelet accumulation was reduced versus control graft results by coating the graft lumenal surfaces with a smooth layer of silicone rubber polymer (0.60 +/- 0.19 x 10(9) platelets per anastomosis; P less than 0.02) but not by coating the grafts using a plasma polymer based on methane, which did not modify graft texture (8.2 +/- 1.7 x 10(9) platelets per graft; P greater than 0.10). The benefit of the silicone rubber coating persisted for at least 48 hr. However, longer term patency was not preserved because 10 of 12 grafts placed had failed within 1 to 2 months.

  4. Thrombus in Transit through Patent Foramen Ovale

    PubMed Central

    Barakat, Iskander; Chalhoub, Michel

    2013-01-01

    A thrombus in transit through a patent foramen ovale (PFO) with impending paradoxical embolism is an extremely rare event. Due to its transient nature, it is unable to identify the thrombus, and most of the cases have been reported at autopsy. We are reporting a case of thrombus straddling the foramen ovale which was diagnosed by echocardiography and treated surgically. Through this personal case, an exhaustive review of the literature was performed. There were 88 cases reported. We concluded that there is no medical consensus about the best option for treatment. Nevertheless, surgery, which is associated with fewer complications of recurrent embolic events than those of thrombolysis and anticoagulation, appeared to be the best approach in patients who are not at a high surgical risk. Anticoagulant treatment appears to be an acceptable therapeutic alternative to surgery, particularly in patients with comorbidities who are at high surgical risk and for patients with small PFO. Thrombolysis is linked to the highest mortality, which could be explained by the severity of the patient's initial presentation. In conclusion, and after the cumulative effects of these case reports, we propose a diagram consisting of the use of the three therapeutic options in the different clinical scenarios. PMID:24826281

  5. Influence of Thrombus Age on the Mechanical Thrombectomy Efficacy of the Amplatz Thrombectomy Device In Vitro

    SciTech Connect

    Grimm, Jan Jahnke, Thomas; Muhle, Claus; Heller, Martin; Mueller-Huelsbeck, Stefan

    2003-06-15

    Purpose: To determine the efficacy of thrombectomy for the Amplatz Thrombectomy Device (ATD) according to the age of the thrombus. Methods: Thrombectomy was performed with the 7 Fr or 8 Fr ATD. Five-day-old or 8-day-old thrombi were made from porcine blood by clotting within silicone tubes to be used in a flow model. Emboli sizes, weight, remaining thrombus and activation time were evaluated. Results: The age of the thrombus had no influence on the activation time necessary for complete thrombolysis. A significant difference was found in the overall amount of embolization only with the 7 Fr device although a similar trend was shown with the 8 Fr device. The amount of embolized thrombotic material was higher for both devices if older thrombi (i.e., 8 days old) we reprocessed. The overall impression was that the 8 Fr device showed slightly better results (less remaining thrombus and embolization). Conclusion: A tendency toward higher amounts of embolization was observed if older thrombi were used in the model. Therefore the interventional radiologist should be aware of the potentially higher risk of peripheral embolization when performing mechanical thrombectomy(with the ATD) in older thrombotic occlusions, especially since the higher rate of embolization was mainly due to an increased proportion of larger embolic particles (1 mm), which are clinically more significant.

  6. Thrombus entrapped in patent foramen ovale: a rare form of thrombus in transit

    PubMed Central

    Bakhshi, Hooman; Meyghani, Zahra; Shakir, Zaid; Chen, Alexander; Kershner, Dawn

    2015-01-01

    In rare cases, thrombus in transit can be entrapped in a patent foramen ovale (PFO). A patient with this condition is at high risk of embolic stroke and death. Early diagnosis and treatment is essential to help prevent stroke and death in these cases. There is no universal management guideline for this rare condition. The decision between medical versus surgical treatment should be made individually for each patient. We present a case of thrombus in transit entrapped in a PFO that was treated medically by lifelong anticoagulation. PMID:26333859

  7. Defective PDI release from platelets and endothelial cells impairs thrombus formation in Hermansky-Pudlak syndrome

    PubMed Central

    Sharda, Anish; Kim, Sarah H.; Jasuja, Reema; Gopal, Srila; Flaumenhaft, Robert; Furie, Barbara C.

    2015-01-01

    Protein disulfide isomerase (PDI), secreted from platelets and endothelial cells after injury, is required for thrombus formation. The effect of platelet and endothelial cell granule contents on PDI-mediated thrombus formation was studied by intravital microscopy using a mouse model of Hermansky-Pudlak syndrome in which platelet dense granules are absent. Platelet deposition and fibrin generation were nearly absent, and extracellular PDI was significantly reduced in HPS6−/− mice after vascular injury. HPS6−/− platelets displayed impaired PDI secretion and impaired exocytosis of α granules, lysosomes, and T granules due to decreased sensitivity to thrombin, but these defects could be corrected by addition of subthreshold amounts of adenosine 5′-diphosphate (ADP). Human Hermansky-Pudlak syndrome platelets demonstrated similar characteristics. Infusion of wild-type platelets rescued thrombus formation in HPS6−/− mice. Human umbilical vein endothelial cells in which the HPS6 gene was silenced displayed impaired PDI secretion and exocytosis of Weibel-Palade bodies. Defective thrombus formation in Hermansky-Pudlak syndrome, associated with impaired exocytosis of residual granules in endothelial cells and platelets, the latter due to deficiency of ADP, is characterized by a defect in T granule secretion, a deficiency in extracellular PDI secretion, and impaired fibrin generation and platelet aggregation. Hermansky-Pudlak syndrome is an example of a hereditary disease whereby impaired PDI secretion contributes to a bleeding phenotype. PMID:25593336

  8. Defective PDI release from platelets and endothelial cells impairs thrombus formation in Hermansky-Pudlak syndrome.

    PubMed

    Sharda, Anish; Kim, Sarah H; Jasuja, Reema; Gopal, Srila; Flaumenhaft, Robert; Furie, Barbara C; Furie, Bruce

    2015-03-01

    Protein disulfide isomerase (PDI), secreted from platelets and endothelial cells after injury, is required for thrombus formation. The effect of platelet and endothelial cell granule contents on PDI-mediated thrombus formation was studied by intravital microscopy using a mouse model of Hermansky-Pudlak syndrome in which platelet dense granules are absent. Platelet deposition and fibrin generation were nearly absent, and extracellular PDI was significantly reduced in HPS6(-/-) mice after vascular injury. HPS6(-/-) platelets displayed impaired PDI secretion and impaired exocytosis of α granules, lysosomes, and T granules due to decreased sensitivity to thrombin, but these defects could be corrected by addition of subthreshold amounts of adenosine 5'-diphosphate (ADP). Human Hermansky-Pudlak syndrome platelets demonstrated similar characteristics. Infusion of wild-type platelets rescued thrombus formation in HPS6(-/-) mice. Human umbilical vein endothelial cells in which the HPS6 gene was silenced displayed impaired PDI secretion and exocytosis of Weibel-Palade bodies. Defective thrombus formation in Hermansky-Pudlak syndrome, associated with impaired exocytosis of residual granules in endothelial cells and platelets, the latter due to deficiency of ADP, is characterized by a defect in T granule secretion, a deficiency in extracellular PDI secretion, and impaired fibrin generation and platelet aggregation. Hermansky-Pudlak syndrome is an example of a hereditary disease whereby impaired PDI secretion contributes to a bleeding phenotype. PMID:25593336

  9. Ultrasonic processor reduces drill-cuttings size and eliminates subsea mounds

    SciTech Connect

    Gaddy, D.E.

    1997-10-06

    Drill cuttings size reduction using ultrasonics eliminated a subsea clean-up and significantly reduced the environmental impact in a North Sea drilling project. Reduction in cuttings size allows for a wider areal dispersion when released into the ocean because they are held in suspension longer than larger sizes. Thus, ocean currents carry the smaller cuttings farther away from the well template, leaving a much wider footprint than larger cuttings sizes. This eliminates the pile-up of cuttings that otherwise would contaminate and harm the marine habitat.

  10. Automated Entire Thrombus Density Measurements for Robust and Comprehensive Thrombus Characterization in Patients with Acute Ischemic Stroke

    PubMed Central

    Santos, Emilie M. M.; Niessen, Wiro J.; Yoo, Albert J.; Berkhemer, Olvert A.; Beenen, Ludo F.

    2016-01-01

    Background and Purpose In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements. Materials and Method In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described using medians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between the median of entire thrombus measurements and commonly applied manual measurements using 3 regions of interest were determined using linear regression. Results Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density. Conclusions Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, discrimination of low and high density thrombi is improved with the automated method. PMID:26765847

  11. The role of neovascularisation in the resolution of venous thrombus.

    PubMed

    Modarai, Bijan; Burnand, Kevin Guiver; Humphries, Julia; Waltham, Matthew; Smith, Alberto

    2005-05-01

    Deep vein thrombosis (DVT) can give rise to chronic debilitating complications, which are expensive to treat. Anticoagulation, the standard therapy for DVT, prevents propagation, but does not remove the existing thrombus, which undergoes slow natural resolution. Alternative forms of treatment that accelerate resolution may arise from a better understanding of the cellular and molecular pathways that regulate the natural resolution of thrombi. This review will outline our current understanding of the mechanisms of thrombus resolution and the role of neovascularisation in this process. Novel experimental treatments that may one day find clinical use are also discussed. The process of thrombus resolution resembles wound healing. The mainly monocytic inflammatory infiltrate, which develops, is associated with the appearance of vascular channels. These cells may drive resolution by encouraging angiogenesis, which contributes to restoration of the vein lumen. Significant numbers of bone marrow-derived progenitor cells have also been found in naturally resolving thrombi, but their precise phenotype and their role in thrombus recanalisation is unclear. Enhanced thrombus neovascularisation and rapid vein recanalisation have been achieved in experimental models with proangiogenic agents. Recent reports of the role of bone marrow-derived progenitor cells in the revascularisation of ischaemic tissues suggest that it may be possible to obtain the same effect by delivering pluripotent or lineage specific stem cells into thrombus. These cells could contribute to thrombus recanalisation by expressing a variety of proangiogenic cytokines or by lining the new vessels that appear within the thrombus. PMID:15886791

  12. Reduced body size and cub recruitment in polar bears associated with sea ice decline

    USGS Publications Warehouse

    Rode, K.D.; Amstrup, Steven C.; Regehr, E.V.

    2010-01-01

    Rates of reproduction and survival are dependent upon adequate body size and condition of individuals. Declines in size and condition have provided early indicators of population decline in polar bears (Ursus maritimus) near the southern extreme of their range. We tested whether patterns in body size, condition, and cub recruitment of polar bears in the southern Beaufort Sea of Alaska were related to the availability of preferred sea ice habitats and whether these measures and habitat availability exhibited trends over time, between 1982 and 2006. The mean skull size and body length of all polar bears over three years of age declined over time, corresponding with long-term declines in the spatial and temporal availability of sea ice habitat. Body size of young, growing bears declined over time and was smaller after years when sea ice availability was reduced. Reduced litter mass and numbers of yearlings per female following years with lower availability of optimal sea ice habitat, suggest reduced reproductive output and juvenile survival. These results, based on analysis of a longterm data set, suggest that declining sea ice is associated with nutritional limitations that reduced body size and reproduction in this population. ?? 2010 by the Ecological Society of America.

  13. Reduced body size and cub recruitment in polar bears associated with sea ice decline.

    PubMed

    Rode, Karyn D; Amstrup, Steven C; Regehr, Eric V

    2010-04-01

    Rates of reproduction and survival are dependent upon adequate body size and condition of individuals. Declines in size and condition have provided early indicators of population decline in polar bears (Ursus maritimus) near the southern extreme of their range. We tested whether patterns in body size, condition, and cub recruitment of polar bears in the southern Beaufort Sea of Alaska were related to the availability of preferred sea ice habitats and whether these measures and habitat availability exhibited trends over time, between 1982 and 2006. The mean skull size and body length of all polar bears over three years of age declined over time, corresponding with long-term declines in the spatial and temporal availability of sea ice habitat. Body size of young, growing bears declined over time and was smaller after years when sea ice availability was reduced. Reduced litter mass and numbers of yearlings per female following years with lower availability of optimal sea ice habitat, suggest reduced reproductive output and juvenile survival. These results, based on analysis of a long-term data set, suggest that declining sea ice is associated with nutritional limitations that reduced body size and reproduction in this population.

  14. Reduced body size and cub recruitment in polar bears associated with sea ice decline.

    PubMed

    Rode, Karyn D; Amstrup, Steven C; Regehr, Eric V

    2010-04-01

    Rates of reproduction and survival are dependent upon adequate body size and condition of individuals. Declines in size and condition have provided early indicators of population decline in polar bears (Ursus maritimus) near the southern extreme of their range. We tested whether patterns in body size, condition, and cub recruitment of polar bears in the southern Beaufort Sea of Alaska were related to the availability of preferred sea ice habitats and whether these measures and habitat availability exhibited trends over time, between 1982 and 2006. The mean skull size and body length of all polar bears over three years of age declined over time, corresponding with long-term declines in the spatial and temporal availability of sea ice habitat. Body size of young, growing bears declined over time and was smaller after years when sea ice availability was reduced. Reduced litter mass and numbers of yearlings per female following years with lower availability of optimal sea ice habitat, suggest reduced reproductive output and juvenile survival. These results, based on analysis of a long-term data set, suggest that declining sea ice is associated with nutritional limitations that reduced body size and reproduction in this population. PMID:20437962

  15. Reducing On-Chip DRAM Energy via Data Transfer Size Optimization

    NASA Astrophysics Data System (ADS)

    Ono, Takatsugu; Inoue, Koji; Murakami, Kazuaki; Yoshida, Kenji

    This paper proposes a software-controllable variable line-size (SC-VLS) cache architecture for low power embedded systems. High bandwidth between logic and a DRAM is realized by means of advanced integrated technology. System-in-Silicon is one of the architectural frameworks to realize the high bandwidth. An ASIC and a specific SRAM are mounted onto a silicon interposer. Each chip is connected to the silicon interposer by eutectic solder bumps. In the framework, it is important to reduce the DRAM energy consumption. The specific DRAM needs a small cache memory to improve the performance. We exploit the cache to reduce the DRAM energy consumption. During application program executions, an adequate cache line size which produces the lowest cache miss ratio is varied because the amount of spatial locality of memory references changes. If we employ a large cache line size, we can expect the effect of prefetching. However, the DRAM energy consumption is larger than a small line size because of the huge number of banks are accessed. The SC-VLS cache is able to change a line size to an adequate one at runtime with a small area and power overheads. We analyze the adequate line size and insert line size change instructions at the beginning of each function of a target program before executing the program. In our evaluation, it is observed that the SC-VLS cache reduces the DRAM energy consumption up to 88%, compared to a conventional cache with fixed 256B lines.

  16. Reducing size-dispersion in one-pot aqueous synthesis of maghemite nanoparticles.

    PubMed

    Drummond, A L; Feitoza, N C; Duarte, G C; Sales, M J A; Silva, L P; Chaker, J A; Bakuzis, A F; Sousa, M H

    2012-10-01

    Nanosized maghemite-like particles with reduced size-distribution were obtained using a one-pot synthesis route in aqueous medium. Forced hydrolysis of iron ions in ammoniac solution led to the formation of magnetite nanoparticles that were oxidized to maghemite in a hydrothermal digestion step that reduced the polydispersity of nanograins. The prepared nanoparticles were characterized by chemical analysis, X-ray diffractometry, magnetization, Raman spectroscopy and transmission electron microscopy measurements. Data showed that 14 nm-sized particles with polydispersity of about 0.14 were produced and, differently from other procedures, neither additional steps nor toxic reagents were needed to reduce size-dispersion or to oxidize magnetite to maghemite. These facts per se turn such nanodevice into a good potential choice for biomedical applications.

  17. Size-dependent mechanical properties of PVA nanofibers reduced via air plasma treatment

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Jin, Yu; Song, Xuefeng; Gao, Jingyun; Han, Xiaobing; Jiang, Xingyu; Zhao, Qing; Yu, Dapeng

    2010-03-01

    Organic nanowires/fibers have great potential in applications such as organic electronics and soft electronic techniques. Therefore investigation of their mechanical performance is of importance. The Young's modulus of poly(vinyl alcohol) (PVA) nanofibers was analyzed by scanning probe microscopy (SPM) methods. Air plasma treatment was used to reduce the nanofibers to different sizes. Size-dependent mechanical properties of PVA nanofibers were studied and revealed that the Young's modulus increased dramatically when the scales became very small (<80 nm).

  18. New mechanism to reduce the size of the monopivot magnetic suspension blood pump: direct drive mechanism.

    PubMed

    Yamane, T; Nishida, M; Kijima, T; Maekawa, J

    1997-07-01

    Size reduction of the monopivot magnetic suspension blood pump has been achieved by reducing the size of the magnetic suspension and employing a direct drive mechanism in place of a brushless DC motor and a magnetic coupling. The flow has also been improved using a closed hollow impeller to remove flow obstruction at the inlet and using radial straight vanes to reduce the impeller speed by 30%. Hemolysis testing was conducted for the new models. Results showed that model DD1 presented only a slightly higher level of hemolysis than a regular extracorporeal centrifugal pump. PMID:9212927

  19. Reduced sample sizes for atrophy outcomes in Alzheimer's disease trials: baseline adjustment.

    PubMed

    Schott, J M; Bartlett, J W; Barnes, J; Leung, K K; Ourselin, S; Fox, N C

    2010-08-01

    Cerebral atrophy rate is increasingly used as an outcome measure for Alzheimer's disease (AD) trials. We used the Alzheimer's disease Neuroimaging initiative (ADNI) dataset to assess if adjusting for baseline characteristics can reduce sample sizes. Controls (n = 199), patients with mild cognitive impairment (MCI) (n = 334) and AD (n = 144) had two MRI scans, 1-year apart; approximately 55% had baseline CSF tau, p-tau, and Abeta1-42. Whole brain (KN-BSI) and hippocampal (HMAPS-HBSI) atrophy rate, and ventricular expansion (VBSI) were calculated for each group; numbers required to power a placebo-controlled trial were estimated. Sample sizes per arm (80% power, 25% absolute rate reduction) for AD were (95% CI): brain atrophy = 81 (64,109), hippocampal atrophy = 88 (68,119), ventricular expansion = 118 (92,157); and for MCI: brain atrophy = 149 (122,188), hippocampal atrophy = 201 (160,262), ventricular expansion = 234 (191,295). To detect a 25% reduction relative to normal aging required increased sample sizes approximately 3-fold (AD), and approximately 5-fold (MCI). Disease severity and Abeta1-42 contributed significantly to atrophy rate variability. Adjusting for 11 predefined covariates reduced sample sizes by up to 30%. Treatment trials in AD should consider the effects of normal aging; adjusting for baseline characteristics can significantly reduce required sample sizes.

  20. A study on reducing of the focal spot size using spatial filtering and phase apodization

    NASA Astrophysics Data System (ADS)

    Savelyev, D.

    2016-08-01

    The resizing of focal spot using an annular diaphragm with phase jump in the scalar paraxial case was investigated numerically. Due to the apodization optical system, we succeeded in reducing the size of the focal spot in 2.3 times.

  1. Do antioxidant vitamins reduce infarct size following acute myocardial ischemia/reperfusion?

    PubMed

    Bellows, S D; Hale, S L; Simkhovich, B Z; Kay, G L; Kloner, R A

    1995-02-01

    There is controversy concerning the ability of antioxidant vitamins to reduce myocardial infarct size. We sought to determine whether a brief prophylactic treatment of vitamin C or vitamin C plus Trolox (a water-soluble form of vitamin E) could reduce myocardial infarct size in an experimental model. We used an anesthetized open-chest rabbit model in which a branch of the circumflex coronary artery was ligated for 30 minutes followed by 4 hours of reperfusion. Experiments were performed in a randomized and blinded fashion. An IV injection of normal saline pH balanced to 7.4 (control group n = 15), vitamin C (150 mg/kg, n = 14), or vitamin C plus Trolox (150 mg/kg plus 100 mg/kg, respectively, n = 15) was administered prior to coronary occlusion. Collateral blood flow during coronary occlusion was measured by radioactive microspheres, myocardial risk zone (AR) was assessed by blue dye injection, and myocardial infarct size (AN) was assessed by triphenyltetrazolium chloride staining. All rabbits received comparable ischemic insult: Collateral blood flow and AR were similar among all three groups. Infarct size, measured as a percent of AR, did not differ significantly among the controls (21%), vitamin C (29%), or the vitamin C plus Trolox (18%) groups. Therefore, in this ischemia/reperfusion model, antioxidant vitamins did not alter myocardial infarct size. PMID:7540423

  2. Shock Reactivity Study on Standard and Reduced Sensitivity RDX of Different Particle Size Distributions

    NASA Astrophysics Data System (ADS)

    McGregor, Nicholas; Lindfors, Allen

    2007-06-01

    Embedded gauge experiments have been performed using a three inch high velocity powder gun to assess the effects of RDX particle size and crystal quality on shock induced reactivity in support of the Combat Safe Insensitive Munitions (CSIM) program. Four monomodal experimental compositions containing 73% solids loading by weight and 27% HTPB binder were tested. The compositions were made using either standard or reduced sensitivity grades of RDX in Class 5 or Class 1 150-300 micron sieve cut particle size classes. Results have shown marked changes in the mode of reaction between the two particle size classes. Both RDX grades at the Class 1 sieve cut particle size distribution showed significant reaction at the shock front as well as behind the front. The Class 5 RDX compositions however showed little reaction at the shock front with rapid growth behind the front. Similar input pressures resulted in a full detonation in a similar distance for like RDX grades. Reaction modes were similar but occurring at greater input pressures for the reduced sensitivity grade of RDX compared to the corresponding particle size distribution standard grade RDX counterpart.

  3. Shock Reactivity Study on Standard and Reduced Sensitivity Rdx of Different Particle Size Distributions

    NASA Astrophysics Data System (ADS)

    McGregor, N. M.; Lindfors, A. J.

    2007-12-01

    Embedded gauge experiments have been performed using a three inch high velocity powder gun to assess the effects of RDX particle size and crystal quality on shock induced reactivity in support of the Combat Safe Insensitive Munitions (CSIM) program. Four monomodal experimental compositions containing 73% solids loading by weight and 27% HTPB binder were tested. The compositions were made using either standard or reduced sensitivity grades of RDX in Class 5 or Class 1 150-300 micron sieve cut particle size classes. Results have shown marked changes in the mode of reaction between the two particle size classes. Both RDX grades at the Class 1 sieve cut particle size distribution showed significant reaction at the shock front as well as behind the front. The Class 5 RDX compositions however showed little reaction at the shock front with rapid growth behind the front. Reaction modes were similar but occurring at greater input pressures for the reduced sensitivity grade of RDX compared to the corresponding particle size distribution standard grade RDX counterpart.

  4. Possible benefits of catheters with lateral holes in coronary thrombus aspiration: a computational study for different clot viscosities and vacuum pressures.

    PubMed

    Soleimani, Sajjad; Dubini, Gabriele; Pennati, Giancarlo

    2014-10-01

    According to a number of clinical studies, coronary aspiration catheters are useful tools to remove a thrombus (blood clot) blocking a coronary artery. However, these thrombectomy devices may fail to remove the blood clot entirely. Few studies have been devoted to a systematic analysis of factors affecting clot aspiration. The geometric characteristics of the aspiration catheter, the physical properties of the thrombus, and the applied vacuum pressure are crucial parameters. In this study, the aspiration of a blood clot blocking a coronary bifurcation is computationally simulated. The clot is modeled as a highly viscous fluid, and a two-phase (blood and clot) problem is solved. The effects of geometric variations in the tip of the coronary catheter, including lateral hole size and location, are investigated considering different aspiration pressures and clot viscosities. A Bird-Carreau model is adopted for blood viscosity, while a power law model is used to describe the clot rheology. Computational results for blood clot aspiration show that the presence of holes in the lateral part of the tip of the catheter can be beneficial depending on clot viscosity, hole features, and applied aspiration pressure. In general, the holes are beneficial when the clot viscosity is low, while aspiration catheters without any extra lateral holes exhibit better performance for higher clot viscosity. However, when higher aspiration pressures are applied, the catheters tend to behave relatively similarly in removing clots with various viscosities, reducing the role of the clot viscosity. PMID:24571089

  5. Management of Vertebral Stenosis Complicated by Presence of Acute Thrombus

    SciTech Connect

    Canyigit, Murat; Arat, Anil Cil, Barbaros E.; Sahin, Gurdal; Turkbey, Baris; Elibol, Bulent

    2007-04-15

    A 44-year-old male presented with multiple punctate acute infarcts of the vertebrobasilar circulation and a computed tomographic angiogram showing stenosis of the right vertebral origin. A digital subtraction angiogram demonstrated a new intraluminal filling defect at the origin of the stenotic vertebral artery where antegrade flow was maintained. This filling defect was accepted to be an acute thrombus of the vertebral origin, most likely due to rupture of a vulnerable plaque. The patient was treated with intravenous heparin. A control angiogram revealed dissolution of the acute thrombus under anticoagulation and the patient was treated with stenting with distal protection. Diffusion-weighted magnetic resonance imaging demonstrated no additional acute ischemic lesions. We were unable to find a similar report in the English literature documenting successful management of an acute vertebral ostial thrombus with anticoagulation. Anticoagulation might be considered prior to endovascular treatment of symptomatic vertebral stenoses complicated by the presence of acute thrombus.

  6. Small portion sizes in worksite cafeterias: do they help consumers to reduce their food intake?

    PubMed Central

    Vermeer, W M; Steenhuis, I H M; Leeuwis, F H; Heymans, M W; Seidell, J C

    2011-01-01

    Background: Environmental interventions directed at portion size might help consumers to reduce their food intake. Objective: To assess whether offering a smaller hot meal, in addition to the existing size, stimulates people to replace their large meal with a smaller meal. Design: Longitudinal randomized controlled trial assessing the impact of introducing small portion sizes and pricing strategies on consumer choices. Setting/participants: In all, 25 worksite cafeterias and a panel consisting of 308 consumers (mean age=39.18 years, 50% women). Intervention: A small portion size of hot meals was offered in addition to the existing size. The meals were either proportionally priced (that is, the price per gram was comparable regardless of the size) or value size pricing was employed. Main outcome measures: Daily sales of small and the total number of meals, consumers' self-reported compensation behavior and frequency of purchasing small meals. Results: The ratio of small meals sales in relation to large meals sales was 10.2%. No effect of proportional pricing was found B=−0.11 (0.33), P=0.74, confidence interval (CI): −0.76 to 0.54). The consumer data indicated that 19.5% of the participants who had selected a small meal often-to-always purchased more products than usual in the worksite cafeteria. Small meal purchases were negatively related to being male (B=−0.85 (0.20), P=0.00, CI: −1.24 to −0.46, n=178). Conclusion: When offering a small meal in addition to the existing size, a percentage of consumers that is considered reasonable were inclined to replace the large meal with the small meal. Proportional prices did not have an additional effect. The possible occurrence of compensation behavior is an issue that merits further attention. PMID:21224829

  7. Effect of ajoene, the major antiplatelet compound from garlic, on platelet thrombus formation.

    PubMed

    Apitz-Castro, R; Badimon, J J; Badimon, L

    1992-10-15

    Ajoene, (E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide, is a potent antiplatelet compound isolated from alcoholic extracts of garlic (Allium sativum). Ajoene reversibly inhibits in vitro platelet aggregation as well as release reaction induced by all known agonists. We used a well characterized cylindrical perfusion chamber to study the effect of ajoene on platelet deposition onto physiological substrates such as pig aortic subendothelium and tunica media as a model of mildly and severely damaged vessel wall respectively. Experiments were performed under flow conditions of high and low shear rate that mimic laminar blood flow in small and medium size arteries (1690 sec-1 and 212 sec-1). Our results indicate that ajoene prevents thrombus formation both at low and high shear rate in citrated whole blood. The inhibitory effect of ajoene on platelet-thrombus formation seems to be dependent on its inhibition of fibrinogen binding, since significantly higher concentrations of ajoene are needed to affect von Willebrand factor binding to GPIIb/IIIa receptors. Further, ajoene does not impair Ristocetin-induced platelet agglutination, mediated by GPIb. Our results suggest that ajoene may be useful for the acute prevention of thrombus formation induced by vascular damage.

  8. Inhibitors of urokinase reduce size of prostate cancer xenografts in severe combined immunodeficient mice.

    PubMed

    Jankun, J; Keck, R W; Skrzypczak-Jankun, E; Swiercz, R

    1997-02-15

    Proteolytic enzymes are required to mediate tumor cell invasion and metastasis. The urokinase plasminogen activator (uPA) is commonly overexpressed by many human cancers. Therefore, uPA is a logical target to inhibit cancer invasion and metastasis. However, uPA inhibitors also reduce tumor growth. We used a mutated form of plasminogen activator inhibitor type 1 to conform a correlation between the inactivation of uPA and tumor size; we have compared these results with the action of p-aminobenzamidine and amiloride, known inhibitors of uPA. Our results show that blocking uPA by uPA inhibitors reduces tumor size in experimental animals. Our molecular simulation of docking inhibitors to the urokinase reveals that all tested small molecule inhibitors bind in proximity of uPA's specificity pocket, a critical site for future search of novel anticancer uPA inhibitors. PMID:9044824

  9. Concentration Effect of Reducing Agents on Green Synthesis of Gold Nanoparticles: Size, Morphology, and Growth Mechanism

    NASA Astrophysics Data System (ADS)

    Kim, Hyun-seok; Seo, Yu Seon; Kim, Kyeounghak; Han, Jeong Woo; Park, Youmie; Cho, Seonho

    2016-04-01

    Under various concentration conditions of reducing agents during the green synthesis of gold nanoparticles (AuNPs), we obtain the various geometry (morphology and size) of AuNPs that play a crucial role in their catalytic properties. Through both theoretical and experimental approaches, we studied the relationship between the concentration of reducing agent (caffeic acid) and the geometry of AuNPs. As the concentration of caffeic acid increases, the sizes of AuNPs were decreased due to the adsorption and stabilizing effect of oxidized caffeic acids (OXCAs). Thus, it turns out that optimal concentration exists for the desired geometry of AuNPs. Furthermore, we investigated the growth mechanism for the green synthesis of AuNPs. As the caffeic acid is added and adsorbed on the surface of AuNPs, the aggregation mechanism and surface free energy are changed and consequently resulted in the AuNPs of various geometry.

  10. Wall stress in media layer of stented three-layered aortic aneurysm at different intraluminal thrombus locations with pulsatile heart cycle.

    PubMed

    Rahmani, Shahrokh; Alagheband, Mohammad; Karimi, Alireza; Alizadeh, Mansour; Navidbakhsh, Mahdi

    2015-05-01

    At the point when the aorta ruptures suddenly, as opposed to as the after-effect of injury, it is for the most part in aortic aneurysm. Aortic aneurysm rupture happens when the wall stress surpasses the strength of the vascular tissue. Intraluminal thrombus (ILT) may have advantages as it can absorb tension and decrease aortic aneurysm wall stress. This study aims to investigate the presence and growth effects of ILT on the wall stress in a stented aneurysm in one heart cycle. A virtual stented aneurysm model with ILT was made to study the flow and wall dynamics using fluid-structure interaction (FSI) analysis. Wall stresses at the center line of media layer of aorta thickness were calculated by two-dimensional axisymmetric finite element analysis. Calculations were executed as thrombus elastic modulus increased from 0.1 to 2 MPa and calculations were repeated as thrombus depth was increased in 10% increment until thrombus filled the whole aneurysm cavity. The von Mises stresses were compared in three sections, namely proximal, aneurysm and distal sections in the abdominal aorta. The wall stress showed its maximum value during a peak flow and pressure and gradually decreased as the pressure and velocity of blood reduced in all three aforementioned sections. As the intraluminal thrombus depth increased from 10% to 100%, the wall stress in distal, proximal and centre of aneurysm during one heart cycle was decreased. Furthermore, increasing the elastic modulus of thrombus from 10% to 100% triggered a reduction in wall stress in proximal, centre of intraluminal thrombus and distal regions during one heart cycle. The achievements of this study may have implications not only for understanding the wall stress in ILT, but also for providing more detailed information about aortic aneurysm with intraluminal thrombus and can help surgeons to do their best.

  11. A DRAMATICALLY REDUCED SIZE IN THE GANTRY DESIGN FOR THE PROTON-CARBON THERAPY.

    SciTech Connect

    TRBOJEVIC, D.; GUPTA, R.; PARKER, B.; KEIL, E.; SESSLER, A.M.

    2006-06-23

    Gantries in the proton/carbon cancer therapy machines represent the major cost and are of the largest size. This report explains a new way to the gantry design. The size and cost of the gantries are reduced and their use is simplified by using the fixed magnetic field. The ''new'' gantry is made of a very large momentum acceptance non-scaling Fixed Field Alternating Gradient (FFAG) quarter and half arc beam lines. The gantry is made of combined function magnets with a very strong focusing and small dispersion function. Additional magnets with a fast response are required to allow adjustments of the beam position for different energies at the beginning of the gantry. Additional strong focusing magnets following the gantry have also to be adjustable to provide required spot size and radial scanning above the patients. The fixed field combined function magnets could be made of small permanent magnets for the proton machine, or of the high temperature superconductors or superconductors for the carbon machine, reducing dramatically the size.

  12. Do calorie-controlled portion sizes of snacks reduce energy intake?

    PubMed

    Stroebele, Nanette; Ogden, Lorraine G; Hill, James O

    2009-06-01

    In a cross-over study, participants (n=59) were randomly assigned to receive either 100 kcal packs or standard size packages of snacks for 1 week. After a minimum of a 1-week washout period, participants received the other form of the snack for 1 week. Snack consumption was recorded by participants in a diary. Participants consumed an average of 186.9 fewer grams of snacks per week when receiving 100 kcal snack packs compared to standard size packages of snacks. Post hoc comparisons revealed the effect of package size depended on both randomization order and study week. Total grams of snacks consumed in week 1 differed significantly between the two randomized groups. In week 2, however, grams of snacks did not differ significantly between the two groups. This interaction was primarily due to a significantly lower consumption of snacks from standard size packages in the week following the portion-controlled packages. The results suggest that portion-controlled packaging reduce total intake from the provided snacks. Further, initial exposure to portion-controlled packages might have increased awareness of portion size such that less was consumed when larger packages were available. PMID:19501784

  13. Configuring the Mesh Size, Side Taper and Wing Depth of Penaeid Trawls to Reduce Environmental Impacts

    PubMed Central

    Broadhurst, Matt K.; Sterling, David J.; Millar, Russell B.

    2014-01-01

    The effects of reducing mesh size while concomitantly varying the side taper and wing depth of a generic penaeid-trawl body were investigated to improve engineering performance and minimize bycatch. Five trawl bodies (with the same codends) were tested across various environmental (e.g. depth and current) and biological (e.g. species and sizes) conditions. The first trawl body comprised 41-mm mesh and represented conventional designs (termed the ‘41 long deep-wing'), while the remaining trawl bodies were made from 32-mm mesh and differed only in their side tapers, and therefore length (i.e. 1N3B or ‘long’ and ∼28o to the tow direction vs 1N5B or ‘short’ and ∼35o) and wing depths (‘deep’–97 T vs ‘shallow’–60 T). There were incremental drag reductions (and therefore fuel savings – by up to 18 and 12% per h and ha trawled) associated with reducing twine area via either modification, and subsequently minimizing otter-board area in attempts to standardize spread. Side taper and wing depth had interactive and varied effects on species selectivity, but compared to the conventional 41 long deep-wing trawl, the 32 short shallow-wing trawl (i.e. the least twine area) reduced the total bycatch by 57% (attributed to more fish swimming forward and escaping). In most cases, all small-meshed trawls also caught more smaller school prawns Metapenaeus macleayi but to decrease this effect it should be possible to increase mesh size slightly, while still maintaining the above engineering benefits and species selectivity. The results support precisely optimizing mesh size as a precursor to any other anterior penaeid-trawl modifications designed to improve environmental performance. PMID:24911786

  14. Statins Improve the Resolution of Established Murine Venous Thrombosis: Reductions in Thrombus Burden and Vein Wall Scarring

    PubMed Central

    Kessinger, Chase W.; Kim, Jin Won; Henke, Peter K.; Thompson, Brian; McCarthy, Jason R.; Hara, Tetsuya; Sillesen, Martin; Margey, Ronan J. P.; Libby, Peter; Weissleder, Ralph; Lin, Charles P.; Jaffer, Farouc A.

    2015-01-01

    Despite anticoagulation therapy, up to one-half of patients with deep vein thrombosis (DVT) will develop the post-thrombotic syndrome (PTS). Improving the long-term outcome of DVT patients at risk for PTS will therefore require new approaches. Here we investigate the effects of statins—lipid-lowering agents with anti-thrombotic and anti-inflammatory properties—in decreasing thrombus burden and decreasing vein wall injury, mediators of PTS, in established murine stasis and non-stasis chemical-induced venous thrombosis (N = 282 mice). Treatment of mice with daily atorvastatin or rosuvastatin significantly reduced stasis venous thrombus burden by 25% without affecting lipid levels, blood coagulation parameters, or blood cell counts. Statin-driven reductions in VT burden (thrombus mass for stasis thrombi, intravital microscopy thrombus area for non-stasis thrombi) compared similarly to the therapeutic anticoagulant effects of low molecular weight heparin. Blood from statin-treated mice showed significant reductions in platelet aggregation and clot stability. Statins additionally reduced thrombus plasminogen activator inhibitor-1 (PAI-1), tissue factor, neutrophils, myeloperoxidase, neutrophil extracellular traps (NETs), and macrophages, and these effects were most notable in the earlier timepoints after DVT formation. In addition, statins reduced DVT-induced vein wall scarring by 50% durably up to day 21 in stasis VT, as shown by polarized light microscopy of picrosirius red-stained vein wall collagen. The overall results demonstrate that statins improve VT resolution via profibrinolytic, anticoagulant, antiplatelet, and anti-vein wall scarring effects. Statins may therefore offer a new pharmacotherapeutic approach to improve DVT resolution and to reduce the post-thrombotic syndrome, particularly in subjects who are ineligible for anticoagulation therapy. PMID:25680183

  15. Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial

    PubMed Central

    Jolly, Sanjit S; Cairns, John A; Yusuf, Salim; Rokoss, Michael J; Gao, Peggy; Meeks, Brandi; Kedev, Sasko; Stankovic, Goran; Moreno, Raul; Gershlick, Anthony; Chowdhary, Saqib; Lavi, Shahar; Niemela, Kari; Bernat, Ivo; Cantor, Warren J; Cheema, Asim N; Steg, Philippe Gabriel; Welsh, Robert C; Sheth, Tej; Bertrand, Olivier F; Avezum, Alvaro; Bhindi, Ravinay; Natarajan, Madhu K; Horak, David; Leung, Raymond C M; Kassam, Saleem; Rao, Sunil V; El-Omar, Magdi; Mehta, Shamir R; Velianou, James L; Pancholy, Samir; Džavík, Vladimír

    2016-01-01

    Summary Background Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice. Methods The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10 732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044. Findings Between Aug 5, 2010, and July 25, 2014, 10 732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not

  16. Cerebral complexity preceded enlarged brain size and reduced olfactory bulbs in Old World monkeys

    PubMed Central

    Gonzales, Lauren A.; Benefit, Brenda R.; McCrossin, Monte L.; Spoor, Fred

    2015-01-01

    Analysis of the only complete early cercopithecoid (Old World monkey) endocast currently known, that of 15-million-year (Myr)-old Victoriapithecus, reveals an unexpectedly small endocranial volume (ECV) relative to body size and a large olfactory bulb volume relative to ECV, similar to extant lemurs and Oligocene anthropoids. However, the Victoriapithecus brain has principal and arcuate sulci of the frontal lobe not seen in the stem catarrhine Aegyptopithecus, as well as a distinctive cercopithecoid pattern of gyrification, indicating that cerebral complexity preceded encephalization in cercopithecoids. Since larger ECVs, expanded frontal lobes, and reduced olfactory bulbs are already present in the 17- to 18-Myr-old ape Proconsul these features evolved independently in hominoids (apes) and cercopithecoids and much earlier in the former. Moreover, the order of encephalization and brain reorganization was apparently different in hominoids and cercopithecoids, showing that brain size and cerebral organization evolve independently. PMID:26138795

  17. Anisotropic remastering for reducing feature sizes on UV nanoimprint lithography replica molds.

    PubMed

    Lausecker, E; Grydlik, M; Brehm, M; Bergmair, I; Mühlberger, M; Fromherz, T; Bauer, G

    2012-04-27

    We present an approach that uses existing nanoimprint molds and reduces the size of the resulting features significantly via a remastering process utilizing the anisotropic etchant tetramethylammonium hydroxide and a mold casting step. Inverted pyramidal structures and V-grooves were imprinted using these 2.5-dimensional (2.5D) replica molds. Pattern transfer into silicon (Si) substrates was established with an intermediate silicon nitride (SiN(x)) layer that can be etched with a much larger selectivity against the imprint resist than the Si substrate. The 2.5D resist profiles are thus transferred back into binary structures in the SiN(x) layer and subsequently into the Si substrate. A substantial size reduction of the diameter of pits from 91 to 33 nm and the width of lines from 600 to 142 nm was achieved.

  18. 10Be measurements at MALT using reduced-size samples of bulk sediments

    NASA Astrophysics Data System (ADS)

    Horiuchi, Kazuho; Oniyanagi, Itsumi; Wasada, Hiroshi; Matsuzaki, Hiroyuki

    2013-01-01

    In order to establish 10Be measurements on reduced-size (1-10 mg) samples of bulk sediments, we investigated four different pretreatment designs using lacustrine and marginal-sea sediments and the AMS system of the Micro Analysis Laboratory, Tandem accelerator (MALT) at The University of Tokyo. The 10Be concentrations obtained from the samples of 1-10 mg agreed within a precision of 3-5% with the values previously determined using corresponding ordinary-size (∼200 mg) samples and the same AMS system. This fact demonstrates reliable determinations of 10Be with milligram levels of recent bulk sediments at MALT. On the other hand, a clear decline of the BeO- beam with tens of micrograms of 9Be carrier suggests that the combination of ten milligrams of sediments and a few hundred micrograms of the 9Be carrier is more convenient at this stage.

  19. Anisotropic remastering for reducing feature sizes on UV nanoimprint lithography replica molds

    NASA Astrophysics Data System (ADS)

    Lausecker, E.; Grydlik, M.; Brehm, M.; Bergmair, I.; Mühlberger, M.; Fromherz, T.; Bauer, G.

    2012-04-01

    We present an approach that uses existing nanoimprint molds and reduces the size of the resulting features significantly via a remastering process utilizing the anisotropic etchant tetramethylammonium hydroxide and a mold casting step. Inverted pyramidal structures and V-grooves were imprinted using these 2.5-dimensional (2.5D) replica molds. Pattern transfer into silicon (Si) substrates was established with an intermediate silicon nitride (SiNx) layer that can be etched with a much larger selectivity against the imprint resist than the Si substrate. The 2.5D resist profiles are thus transferred back into binary structures in the SiNx layer and subsequently into the Si substrate. A substantial size reduction of the diameter of pits from 91 to 33 nm and the width of lines from 600 to 142 nm was achieved.

  20. ABA-deficiency results in reduced plant and fruit size in tomato.

    PubMed

    Nitsch, L; Kohlen, W; Oplaat, C; Charnikhova, T; Cristescu, S; Michieli, P; Wolters-Arts, M; Bouwmeester, H; Mariani, C; Vriezen, W H; Rieu, I

    2012-06-15

    Abscisic acid (ABA) deficient mutants, such as notabilis and flacca, have helped elucidating the role of ABA during plant development and stress responses in tomato (Solanum lycopersicum L.). However, these mutants have only moderately decreased ABA levels. Here we report on plant and fruit development in the more strongly ABA-deficient notabilis/flacca (not/flc) double mutant. We observed that plant growth, leaf-surface area, drought-induced wilting and ABA-related gene expression in the different genotypes were strongly correlated with the ABA levels and thus most strongly affected in the not/flc double mutants. These mutants also had reduced fruit size that was caused by an overall smaller cell size. Lower ABA levels in fruits did not correlate with changes in auxin levels, but were accompanied by higher ethylene evolution rates. This suggests that in a wild-type background ABA stimulates cell enlargement during tomato fruit growth via a negative effect on ethylene synthesis.

  1. Extracellular Thiol Isomerases and Their Role in Thrombus Formation

    PubMed Central

    Schulman, Sol; Bendapudi, Pavan; Sharda, Anish; Chen, Vivien; Bellido-Martin, Lola; Jasuja, Reema; Furie, Barbara C.; Flaumenhaft, Robert

    2016-01-01

    Abstract Significance: The mammalian endoplasmic reticulum (ER) houses a large family of twenty thioredoxin-like proteins of which protein disulfide isomerase (PDI) is the archetypal member. Although the PDI family is best known for its role in oxidative protein folding of secretory proteins in the ER, these thioredoxin-like proteins fulfill ever-expanding roles, both within the secretory pathway and beyond. Recent Advances: Secreted PDI family proteins have now been shown to serve a critical role in platelet thrombus formation and fibrin generation. Utilizing intravital microscopy to visualize thrombus formation in mice, we have demonstrated the presence of extracellular PDI antigen during thrombus formation following injury of the vascular wall. Inhibition of PDI abrogates thrombus formation in vivo (16, 26, 46, 55). These observations have been extended to other PDI family members, including ERp57 (39, 116, 118, 123) and ERp5 (77). The vascular thiol isomerases are those PDI family members secreted from platelets and/or endothelium (40): PDI, ERp57, ERp5, ERp72, ERp44, ERp29, and TMX3. We focus here on PDI (16, 46, 55), ERp57 (39, 116, 118, 123), and ERp5 (77), which have been implicated in thrombus formation in vivo. Critical Issues: It would appear that a system of thiol isomerase redox catalysts has been hijacked from the ER to regulate thrombus formation in the vasculature. Future Directions: How this redox system is trafficked to and regulated at the cell surface, the identity of extracellular substrates, why so many thiol isomerases are required, and which thiol isomerase functions are necessary are critical unanswered questions in understanding the role of thiol isomerases in thrombus formation. Antioxid. Redox Signal. 24, 1–15. PMID:26467859

  2. Free radical scavenger, edaravone, reduces the lesion size of lacunar infarction in human brain ischemic stroke

    PubMed Central

    2011-01-01

    Background Although free radicals have been reported to play a role in the expansion of ischemic brain lesions, the effect of free radical scavengers is still under debate. In this study, the temporal profile of ischemic stroke lesion sizes was assessed for more than one year to evaluate the effect of edaravone which might reduce ischemic damage. Methods We sequentially enrolled acute ischemic stroke patients, who admitted between April 2003 and March 2004, into the edaravone(-) group (n = 83) and, who admitted between April 2004 and March 2005, into the edaravone(+) group (n = 93). Because, edaravone has been used as the standard treatment after April 2004 in our hospital. To assess the temporal profile of the stroke lesion size, the ratio of the area [T2-weighted magnetic resonance images (T2WI)/iffusion-weighted magnetic resonance images (DWI)] were calculated. Observations on T2WI were continued beyond one year, and observational times were classified into subacute (1-2 months after the onset), early chronic (3-6 month), late chronic (7-12 months) and old (≥13 months) stages. Neurological deficits were assessed by the National Institutes of Health Stroke Scale upon admission and at discharge and by the modified Rankin Scale at 1 year following stroke onset. Results Stroke lesion size was significantly attenuated in the edaravone(+) group compared with the edaravone(-) group in the period of early and late chronic observational stages. However, this reduction in lesion size was significant within a year and only for the small-vessel occlusion stroke patients treated with edaravone. Moreover, patients with small-vessel occlusion strokes that were treated with edaravone showed significant neurological improvement during their hospital stay, although there were no significant differences in outcome one year after the stroke. Conclusion Edaravone treatment reduced the volume of the infarct and improved neurological deficits during the subacute period, especially

  3. The Role of Social Norms in the Portion Size Effect: Reducing Normative Relevance Reduces the Effect of Portion Size on Consumption Decisions

    PubMed Central

    Versluis, Iris; Papies, Esther K.

    2016-01-01

    People typically eat more from large portions of food than from small portions. An explanation that has often been given for this so-called portion size effect is that the portion size acts as a social norm and as such communicates how much is appropriate to eat. In this paper, we tested this explanation by examining whether manipulating the relevance of the portion size as a social norm changes the portion size effect, as assessed by prospective consumption decisions. We conducted one pilot experiment and one full experiment in which participants respectively indicated how much they would eat or serve themselves from a given amount of different foods. In the pilot (N = 63), we manipulated normative relevance by allegedly basing the portion size on the behavior of either students of the own university (in-group) or of another university (out-group). In the main experiment (N = 321), we told participants that either a minority or majority of people similar to them approved of the portion size. Results show that in both experiments, participants expected to serve themselves and to eat more from larger than from smaller portions. As expected, however, the portion size effect was less pronounced when the reference portions were allegedly based on the behavior of an out-group (pilot) or approved only by a minority (main experiment). These findings suggest that the portion size indeed provides normative information, because participants were less influenced by it if it communicated the behaviors or values of a less relevant social group. In addition, in the main experiment, the relation between portion size and the expected amount served was partially mediated by the amount that was considered appropriate, suggesting that concerns about eating an appropriate amount indeed play a role in the portion size effect. However, since the portion size effect was weakened but not eliminated by the normative relevance manipulations and since mediation was only partial, other

  4. Radiation damage in protein crystals is reduced with a micron-sized X-ray beam

    PubMed Central

    Sanishvili, Ruslan; Yoder, Derek W.; Pothineni, Sudhir Babu; Rosenbaum, Gerd; Xu, Shenglan; Vogt, Stefan; Stepanov, Sergey; Makarov, Oleg A.; Corcoran, Stephen; Benn, Richard; Nagarajan, Venugopalan; Smith, Janet L.; Fischetti, Robert F.

    2011-01-01

    Radiation damage is a major limitation in crystallography of biological macromolecules, even for cryocooled samples, and is particularly acute in microdiffraction. For the X-ray energies most commonly used for protein crystallography at synchrotron sources, photoelectrons are the predominant source of radiation damage. If the beam size is small relative to the photoelectron path length, then the photoelectron may escape the beam footprint, resulting in less damage in the illuminated volume. Thus, it may be possible to exploit this phenomenon to reduce radiation-induced damage during data measurement for techniques such as diffraction, spectroscopy, and imaging that use X-rays to probe both crystalline and noncrystalline biological samples. In a systematic and direct experimental demonstration of reduced radiation damage in protein crystals with small beams, damage was measured as a function of micron-sized X-ray beams of decreasing dimensions. The damage rate normalized for dose was reduced by a factor of three from the largest (15.6 μm) to the smallest (0.84 μm) X-ray beam used. Radiation-induced damage to protein crystals was also mapped parallel and perpendicular to the polarization direction of an incident 1-μm X-ray beam. Damage was greatest at the beam center and decreased monotonically to zero at a distance of about 4 μm, establishing the range of photoelectrons. The observed damage is less anisotropic than photoelectron emission probability, consistent with photoelectron trajectory simulations. These experimental results provide the basis for data collection protocols to mitigate with micron-sized X-ray beams the effects of radiation damage. PMID:21444772

  5. Culprit lesion thrombus burden after manual thrombectomy or percutaneous coronary intervention-alone in ST-segment elevation myocardial infarction: the optical coherence tomography sub-study of the TOTAL (ThrOmbecTomy versus PCI ALone) trial

    PubMed Central

    Bhindi, Ravinay; Kajander, Olli A.; Jolly, Sanjit S.; Kassam, Saleem; Lavi, Shahar; Niemelä, Kari; Fung, Anthony; Cheema, Asim N.; Meeks, Brandi; Alexopoulos, Dimitrios; Kočka, Viktor; Cantor, Warren J.; Kaivosoja, Timo P.; Shestakovska, Olga; Gao, Peggy; Stankovic, Goran; Džavík, Vladimír; Sheth, Tej

    2016-01-01

    Aims Manual thrombectomy has been proposed as a strategy to reduce thrombus burden during primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). However, the effectiveness of manual thrombectomy in reducing thrombus burden is uncertain. In this substudy of the TOTAL (ThrOmbecTomy versus PCI ALone) trial, we compared the thrombus burden at the culprit lesion using optical coherence tomography (OCT) in patients treated with thrombectomy vs. PCI-alone. Methods and results The TOTAL trial (N = 10 732) was an international, multicentre, randomized trial of thrombectomy (using the Export catheter, Medtronic Cardiovascular, Santa Rosa, CA, USA) in STEMI patients treated with primary PCI. The OCT sub-study prospectively enrolled 214 patients from 13 sites in 5 countries. Optical coherence tomography was performed immediately after thrombectomy or PCI-alone and then repeated after stent deployment. Thrombus quantification was performed by an independent core laboratory blinded to treatment assignment. The primary outcome of pre-stent thrombus burden as a percentage of segment analysed was 2.36% (95% CI: 1.73–3.22) in the thrombectomy group and 2.88% (95% CI: 2.12–3.90) in the PCI-alone group (P = 0.373). Absolute pre-stent thrombus volume was not different (2.99 vs. 3.74 mm3, P = 0.329). Other secondary outcomes of pre-stent quadrants of thrombus, post–stent atherothrombotic burden, and post-stent atherothrombotic volume were not different between groups. Conclusion Manual thrombectomy did not reduce pre-stent thrombus burden at the culprit lesion compared with PCI-alone. Both strategies were associated with low thrombus burden at the lesion site after the initial intervention to restore flow. PMID:25994742

  6. Irradiation testing of full-sized, reduced-enrichment fuel elements

    SciTech Connect

    Snelgrove, J.L.; Copeland, G.L.

    1983-01-01

    The current status of the irradiation testing of full-sized, reduced-enrichment fuel elements and fuel rods under the US Reduced Enrichment Research and Test Reactor Program is reported. Being tested are UAl/sub x/-Al, U/sub 3/O/sub 8/-Al, U/sub 3/Si/sub 2/-Al, and U/sub 3/Si-Al dispersion fuels and UZrH/sub x/ (TRIGA) fuel at uranium densities in the fuel meat ranging from 1.7 to 6.0 Mg/m/sup 3/. Generally good performance has been experienced to date. Some preliminary results of postirradiation examinations are also included. A whole-core demonstration in the Oak Ridge Research Reactor is planned. Some details of this demonstration are provided.

  7. Charge reduced electrospray size spectrometry of mega- and gigadalton complexes: whole viruses and virus fragments.

    PubMed

    Hogan, Christopher J; Kettleson, Eric M; Ramaswami, Bala; Chen, Da-Ren; Biswas, Pratim

    2006-02-01

    The ability to analyze and identify large macromolecular complexes whose molecular weight is beyond the analyzable range of mass spectrometry is of great interest. The size of such complexes makes them suitable for analysis via mobility size spectrometry. In this work, charge reduced electrospray size spectrometry was used for the analysis of bacteriophage viruses with total molecular masses ranging from 3.6 MDa up to the gigadalton range. The electrospray source used was operated in "cone jet" mode with a mean droplet diameter of 170.56 nm. Bacteriophage MS2 was found to have a mobility diameter of 24.13 +/- 0.06 nm and remain highly viable after the electrospray process. Larger bacteriophages T2 and T4 have lengths greater than the diameter of the electrospray jet and droplets; thus, they could not be completely enclosed and were found to fragment at the virus capsid head-tail noncovalent interface during either the jet formation or jet breakup process. No viable T2 or T4 virions were detectable after being electrosprayed. While the exact mechanism of fragmentation could not be determined, it is proposed here that macromolecular fragmentation at noncovalent interfaces occurs due to mechanically and electrically induced stresses during jet formation and jet breakup. Bacteriophage T4 capsid heads were found to be statistically significantly larger than bacteriophage T2 capsid heads, with a mean peak diameter of 88.32 +/- 1.02 nm for T4 and 87.03 +/- 0.18 nm for T2. While capsid head fragments were detectable, tail and tail-fiber fragments could not be detected by size spectrometric analysis. This is attributed to the fact that the contractile tails of bacteriophage T2 and T4 virions mechanically deform to a varying degree while confined within the smaller jet and droplets. Further evidence of contractile tail deformation during the electrospray process was found by measuring the size spectrum of bacteriophage lambda, which has a noncontractile tail. Bacteriophage

  8. Public School Education: The Case for Reduced Class Size. Why the Present Class Size is Not Working and What Can We Do about It?

    ERIC Educational Resources Information Center

    Graham, Evol

    2009-01-01

    By reducing class size we will close the achievement gap in public school education, caused by prior neglect especially since the civil rights era of the sixties. Additional, highly qualified and specialized teachers will more effectively manage a smaller class size and serve more individual student needs in the crucial early grades, where a solid…

  9. Eplerenone reduced lesion size in early but not advanced atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Raz-Pasteur, Ayelet; Gamliel-Lazarovich, Aviva; Coleman, Raymond; Keidar, Shlomo

    2012-12-01

    The beneficial effects of eplerenone, a specific mineralocorticoid receptor blocker, were previously demonstrated in early atherosclerosis (ATS). The aim of the present study was to evaluate the effect of eplerenone in advanced versus early ATS. Apolipoprotein E knockout mice aged 16 or 32 weeks were randomly divided into eplerenone (100 mg·kg·d) or vehicle treatment for 14 weeks. Eplerenone reduced atherosclerotic lesion size by 51% only in early ATS. In peritoneal macrophages obtained from these mice, eplerenone reduced messenger RNA expression of pro-inflammatory markers, interleukin 6, tumor necrosis factor α, monocyte chemotactic protein 1, and increased anti-inflammatory marker arginase 1 to a greater extent in early compared with advanced ATS. These changes correspond to macrophage polarization toward alternative inflammatory phenotype. Messenger RNA expression of the mineralocorticoid receptor and aldosterone synthase were also reduced by eplerenone to a greater extent in early ATS, and these might increase the sensitivity of macrophages to mineralocorticoid blockade in early ATS. The results of the present study point to the benefits of early initiation of treatment with eplerenone in reducing experimental ATS.

  10. Thrombus Degradation by Fibrinolytic Enzyme of Stenotrophomonas sp. Originated from Indonesian Soybean-Based Fermented Food on Wistar Rats.

    PubMed

    Nailufar, Florensia; Tjandrawinata, Raymond R; Suhartono, Maggy T

    2016-01-01

    Objective. To evaluate thrombus degrading effect of a fibrinolytic enzyme from food origin Stenotrophomonas sp. of Indonesia. Methods. Prior to animal study, the enzyme safety was tested using cell culture. The effect on expression of tissue plasminogen activator was also analysed in the cell culture. For in vivo studies, 25 Wistar rats were used: normal control, negative control, treatment groups with crude and semipurified enzyme given orally at 25 mg/kg, and positive control group which received Lumbrokinase at 25 mg/kg. Blood clot in the tail was induced by kappa carrageenan injection at 1 mg/kg BW. Results. Experiment with cell culture confirmed the enzyme safety at the concentration used and increased expression of tPA. Decreasing of thrombus was observed in the positive group down to 70.35 ± 23.11% of the negative control animals (100%). The thrombus observed in the crude enzyme treatment was down to 56.99 ± 15.95% and 71.5 ± 15.7% for semipurified enzyme. Scanning electron microscopy showed clearly that bood clots were found in the animals injected with kappa carrageenan; however, in the treatment and positive groups, the clot was much reduced. Conclusions. Oral treatment of enzyme from Stenotrophomonas sp. of Indonesian fermented food was capable of degrading thrombus induced in Wistar rats. PMID:27635131

  11. Thrombus Degradation by Fibrinolytic Enzyme of Stenotrophomonas sp. Originated from Indonesian Soybean-Based Fermented Food on Wistar Rats

    PubMed Central

    Tjandrawinata, Raymond R.

    2016-01-01

    Objective. To evaluate thrombus degrading effect of a fibrinolytic enzyme from food origin Stenotrophomonas sp. of Indonesia. Methods. Prior to animal study, the enzyme safety was tested using cell culture. The effect on expression of tissue plasminogen activator was also analysed in the cell culture. For in vivo studies, 25 Wistar rats were used: normal control, negative control, treatment groups with crude and semipurified enzyme given orally at 25 mg/kg, and positive control group which received Lumbrokinase at 25 mg/kg. Blood clot in the tail was induced by kappa carrageenan injection at 1 mg/kg BW. Results. Experiment with cell culture confirmed the enzyme safety at the concentration used and increased expression of tPA. Decreasing of thrombus was observed in the positive group down to 70.35 ± 23.11% of the negative control animals (100%). The thrombus observed in the crude enzyme treatment was down to 56.99 ± 15.95% and 71.5 ± 15.7% for semipurified enzyme. Scanning electron microscopy showed clearly that bood clots were found in the animals injected with kappa carrageenan; however, in the treatment and positive groups, the clot was much reduced. Conclusions. Oral treatment of enzyme from Stenotrophomonas sp. of Indonesian fermented food was capable of degrading thrombus induced in Wistar rats.

  12. Thrombus Degradation by Fibrinolytic Enzyme of Stenotrophomonas sp. Originated from Indonesian Soybean-Based Fermented Food on Wistar Rats

    PubMed Central

    Tjandrawinata, Raymond R.

    2016-01-01

    Objective. To evaluate thrombus degrading effect of a fibrinolytic enzyme from food origin Stenotrophomonas sp. of Indonesia. Methods. Prior to animal study, the enzyme safety was tested using cell culture. The effect on expression of tissue plasminogen activator was also analysed in the cell culture. For in vivo studies, 25 Wistar rats were used: normal control, negative control, treatment groups with crude and semipurified enzyme given orally at 25 mg/kg, and positive control group which received Lumbrokinase at 25 mg/kg. Blood clot in the tail was induced by kappa carrageenan injection at 1 mg/kg BW. Results. Experiment with cell culture confirmed the enzyme safety at the concentration used and increased expression of tPA. Decreasing of thrombus was observed in the positive group down to 70.35 ± 23.11% of the negative control animals (100%). The thrombus observed in the crude enzyme treatment was down to 56.99 ± 15.95% and 71.5 ± 15.7% for semipurified enzyme. Scanning electron microscopy showed clearly that bood clots were found in the animals injected with kappa carrageenan; however, in the treatment and positive groups, the clot was much reduced. Conclusions. Oral treatment of enzyme from Stenotrophomonas sp. of Indonesian fermented food was capable of degrading thrombus induced in Wistar rats. PMID:27635131

  13. A Novel Mechanical Thrombectomy Device for Retrieval of Intravascular Thrombus

    SciTech Connect

    Monsky, Wayne L.; Finitsis, Stephanos; Cicco, Dino De; Brock, John M.; Kucharczyk, John; Latchaw, Richard E.

    2011-04-15

    Purpose: Thrombotic and embolic vascular occlusion represents a leading cause of morbidity and mortality. Currently available thrombectomy devices have limitations, including difficulty removing organized thrombus and clot fragmentation with distal embolization. A novel mechanical thrombectomy device (MTD), designed to remove both hard and soft thrombus without trauma to the blood vessel, was tested in preclinical porcine models evaluating efficacy, safety, and ease of use. Materials and Methods: A total of 26 vessels in 14 pigs underwent mechanical thrombectomy with MTD. Thrombectomy was performed in nine superficial femoral arteries, eight subclavian arteries, five primary branches of the subclavian artery, lateral thoracic artery or the thyrocervical trunk, and four external carotids. Subacute organized fibrin-laden thrombus was injected into the arteries producing vascular occlusion. The MTD was then used for thrombectomy to restore patency and blood flow. Results: Intact thrombus was retrieved from 24 of 26 of the vessels with a single pass of the MTD, resulting in complete restoration of patency in 21 vessels and partial patency in 4 vessels. In 8 cases that used an early design, the embolic material fragmented during withdrawal from the access sheath. In 4 procedures that used an early design, the MTD failed to deploy fully and the embolus was not completely captured. No intraprocedural complications or vascular damage occurred. Conclusions: The present pilot studies demonstrate basic safety and efficacy of a novel MTD with design attributes suitable for retrieval of intact acute and organized chronic thrombus. The device has potential intracranial and peripheral utility.

  14. Left ventricular mass: A tumor or a thrombus diagnostic dilemma

    PubMed Central

    Dinesh Kumar, U. S.; Shetty, Shyam Prasad; Sujay, K. R.; Wali, Murugesh

    2016-01-01

    Left ventricular (LV) mass is a rare condition, of which the most common is thrombus. Echocardiography is a very useful modality of investigation to evaluate the LV mass. We are reporting a case of LV mass presenting with neurological symptom. The diagnosis of this mass was dilemma as the echocardiographic features were favoring tumor as well as thrombi. Mass (a) measuring 3.8 cm × 1.9 cm attached to the left ventricle apex appeared to be pedunculated tumor and mass (b) measuring 2.4 cm × 1.8 cm attached to the chordae of anterior mitral leaflet resembled a thrombus or an embolized tumor entangled in the chordae. A differential diagnosis for the LV mass is thrombus, tumors such as fibroma, and vegetation. Preoperative detection of a thrombus leads to an alteration in surgical steps. A large and mobile thrombus with or without a hemodynamic alteration is an indication for surgical removal to prevent stroke, myocardial infarction, mesenteric ischemia, renal infarction, gangrene of the limbs, and mortality. PMID:27716707

  15. Insulin Resistance in Human iPS Cells Reduces Mitochondrial Size and Function

    PubMed Central

    Burkart, Alison M.; Tan, Kelly; Warren, Laura; Iovino, Salvatore; Hughes, Katelyn J.; Kahn, C. Ronald; Patti, Mary-Elizabeth

    2016-01-01

    Insulin resistance, a critical component of type 2 diabetes (T2D), precedes and predicts T2D onset. T2D is also associated with mitochondrial dysfunction. To define the cause-effect relationship between insulin resistance and mitochondrial dysfunction, we compared mitochondrial metabolism in induced pluripotent stem cells (iPSC) from 5 healthy individuals and 4 patients with genetic insulin resistance due to insulin receptor mutations. Insulin-resistant iPSC had increased mitochondrial number and decreased mitochondrial size. Mitochondrial oxidative function was impaired, with decreased citrate synthase activity and spare respiratory capacity. Simultaneously, expression of multiple glycolytic enzymes was decreased, while lactate production increased 80%. These perturbations were accompanied by an increase in ADP/ATP ratio and 3-fold increase in AMPK activity, indicating energetic stress. Insulin-resistant iPSC also showed reduced catalase activity and increased susceptibility to oxidative stress. Thus, insulin resistance can lead to mitochondrial dysfunction with reduced mitochondrial size, oxidative activity, and energy production. PMID:26948272

  16. The development of reduced size STR amplicons as tools for analysis of degraded DNA.

    PubMed

    Butler, John M; Shen, Yin; McCord, Bruce R

    2003-09-01

    New multiplex PCR sets of commonly used short tandem repeat (STR) markers have been developed to produce PCR products that are reduced in size when compared to standard commercial STR kits. The reduction in size of these amplicons can facilitate the examination and analysis of degraded DNA evidence by improving amplification efficiency. This "miniSTR" approach will permit current forensic practitioners to use STR markers and instrumentation already present in their laboratories and to generate genotyping data that is directly comparable to reference samples and searchable through the FBI's Combined DNA Index System (CODIS) databases. This paper discusses the development of these new primer sets and presents some initial results in the analysis of degraded and aged DNA samples. A method for removal of problematic fluorescent dye artifacts is also described. Comparison studies in over 100 samples have verified that these miniSTR primers can provide fully concordant results to commercial STR kits and can provide improved signal from degraded DNA specimens. These miniplex sets should prove valuable in the analysis of samples where allele dropout and reduced sensitivity of larger STR alleles occurs.

  17. REDUCED CHLOROPLAST COVERAGE genes from Arabidopsis thaliana help to establish the size of the chloroplast compartment

    PubMed Central

    Larkin, Robert M.; Stefano, Giovanni; Ruckle, Michael E.; Stavoe, Andrea K.; Sinkler, Christopher A.; Brandizzi, Federica; Malmstrom, Carolyn M.; Osteryoung, Katherine W.

    2016-01-01

    Eukaryotic cells require mechanisms to establish the proportion of cellular volume devoted to particular organelles. These mechanisms are poorly understood. From a screen for plastid-to-nucleus signaling mutants in Arabidopsis thaliana, we cloned a mutant allele of a gene that encodes a protein of unknown function that is homologous to two other Arabidopsis genes of unknown function and to FRIENDLY, which was previously shown to promote the normal distribution of mitochondria in Arabidopsis. In contrast to FRIENDLY, these three homologs of FRIENDLY are found only in photosynthetic organisms. Based on these data, we proposed that FRIENDLY expanded into a small gene family to help regulate the energy metabolism of cells that contain both mitochondria and chloroplasts. Indeed, we found that knocking out these genes caused a number of chloroplast phenotypes, including a reduction in the proportion of cellular volume devoted to chloroplasts to 50% of wild type. Thus, we refer to these genes as REDUCED CHLOROPLAST COVERAGE (REC). The size of the chloroplast compartment was reduced most in rec1 mutants. The REC1 protein accumulated in the cytosol and the nucleus. REC1 was excluded from the nucleus when plants were treated with amitrole, which inhibits cell expansion and chloroplast function. We conclude that REC1 is an extraplastidic protein that helps to establish the size of the chloroplast compartment, and that signals derived from cell expansion or chloroplasts may regulate REC1. PMID:26862170

  18. Traversing boundaries: thrombus in transit with paradoxical embolism

    PubMed Central

    Miriyala, Varun; Faraj, Kirmanj; Nagra, Bipinpreet

    2016-01-01

    A 72-year-old male is diagnosed with paradoxical embolus after he presented with concurrent deep vein thrombosis, stroke, and multiple arterial emboli in the presence of a patent foramen ovale (PFO). Paradoxical embolus requires the passage of a thrombus from the venous into the arterial circulation through a right-to-left shunt leading to systemic embolism. But, despite the high incidence of PFO (27.3% across all age groups by autopsy), paradoxical embolism (PDE) is uncommon, representing <2% of all arterial emboli. We present a case report where a thrombus has been directly observed passing through the PFO during an echocardiogram study; thus, clearly delineating the true cause of multiple thromboemboli and stoke in our patient. Subsequent Transesophageal Echocardiography (TEE) also interestingly showed the thrombus in transit in the aorta and pulmonary artery. PMID:27609716

  19. Traversing boundaries: thrombus in transit with paradoxical embolism.

    PubMed

    Miriyala, Varun; Awan, Muhammad Umer; Faraj, Kirmanj; Nagra, Bipinpreet

    2016-01-01

    A 72-year-old male is diagnosed with paradoxical embolus after he presented with concurrent deep vein thrombosis, stroke, and multiple arterial emboli in the presence of a patent foramen ovale (PFO). Paradoxical embolus requires the passage of a thrombus from the venous into the arterial circulation through a right-to-left shunt leading to systemic embolism. But, despite the high incidence of PFO (27.3% across all age groups by autopsy), paradoxical embolism (PDE) is uncommon, representing <2% of all arterial emboli. We present a case report where a thrombus has been directly observed passing through the PFO during an echocardiogram study; thus, clearly delineating the true cause of multiple thromboemboli and stoke in our patient. Subsequent Transesophageal Echocardiography (TEE) also interestingly showed the thrombus in transit in the aorta and pulmonary artery.

  20. Intracardiac echocardiography for immediate detection of intracardiac thrombus formation.

    PubMed

    Baran, Jakub; Sikorska, Agnieszka; Piotrowski, Roman; Kryński, Tomasz

    2015-12-01

    An 85-year-old man with persistent atrial flutter (AFL) with slow ventricular rate of 44/min, causing fatigue and presyncope, was referred for urgent treatment. In spite of thromboembolic risk scale value 4, he had not been treated with anticoagulants because of high risk of bleeding. The decision was made to perform urgent catheter ablation to interrupt and cure AFL. Intracardiac echocardiography probe was placed in the pulmonary artery and visualized left atrial appendage free from thrombus with its proper function. Heparin was administered and AFL stopped during energy application. Intracardiac echocardiography showed immediate thrombus formation in left atrial appendage owing to complete atrial standstill and no retrograde conduction during hemodynamically effective escape nodal rhythm. This case report shows that in patients with sinus node disease effective ablation of AFL with escape rhythm without retrograde conduction to the atria may result in complete 'electrically induced' atrial standstill and immediate thrombus formation.

  1. Traversing boundaries: thrombus in transit with paradoxical embolism.

    PubMed

    Miriyala, Varun; Awan, Muhammad Umer; Faraj, Kirmanj; Nagra, Bipinpreet

    2016-01-01

    A 72-year-old male is diagnosed with paradoxical embolus after he presented with concurrent deep vein thrombosis, stroke, and multiple arterial emboli in the presence of a patent foramen ovale (PFO). Paradoxical embolus requires the passage of a thrombus from the venous into the arterial circulation through a right-to-left shunt leading to systemic embolism. But, despite the high incidence of PFO (27.3% across all age groups by autopsy), paradoxical embolism (PDE) is uncommon, representing <2% of all arterial emboli. We present a case report where a thrombus has been directly observed passing through the PFO during an echocardiogram study; thus, clearly delineating the true cause of multiple thromboemboli and stoke in our patient. Subsequent Transesophageal Echocardiography (TEE) also interestingly showed the thrombus in transit in the aorta and pulmonary artery. PMID:27609716

  2. Synthetic thrombus model for in vitro studies of laser thrombolysis

    SciTech Connect

    Hermes, R.E.; Trajkovska, K.

    1998-07-01

    Laser thrombolysis is the controlled ablation of a thrombus (blood clot) blockage in a living arterial system. Theoretical modeling of the interaction of laser light with thrombi relies on the ability to perform in vitro experiments with well characterized surrogate materials. A synthetic thrombus formulation may offer more accurate results when compared to in vivo clinical experiments. The authors describe the development of new surrogate materials based on formulations incorporating chick egg, guar gum, modified food starch, and a laser light absorbing dye. The sound speed and physical consistency of the materials were very close to porcine (arterial) and human (venous) thrombi. Photographic and videotape recordings of pulsed dye laser ablation experiments under various experimental conditions were used to evaluate the new material as compared to in vitro tests with human (venous) thrombus. The characteristics of ablation and mass removal were similar to that of real thrombi, and therefore provide a more realistic model for in vitro laser thrombolysis when compared to gelatin.

  3. Hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus.

    PubMed

    Van Treeck, Benjamin J; Masoud, Amgad G

    2014-01-01

    Clinical hypothyroidism is the most common hormone deficiency in the United States and is found in 0.3% of the U.S. population. It is associated with characteristic symptoms that can be readily identified by a careful history and physical examination. Hypothyroidism affects many bodily systems; in particular the cardiovascular system is impacted via multiple mechanisms.3 Occasionally hypothyroidism leads to transient left ventricular systolic dysfunction, termed hypothyroid cardiomyopathy. A rare sequela of this condition is a left ventricular thrombus, which has been described in two case reports thus far. Here we report a third case of reversible hypothyroid cardiomyopathy complicated by a left ventricular laminar thrombus. PMID:25438369

  4. Eco-evolutionary dynamics: fluctuations in population growth rate reduce effective population size in chinook salmon.

    PubMed

    Waples, Robin S; Jensen, David W; McClure, Michelle

    2010-03-01

    We empirically assess the relationship between population growth rate (lambda, a parameter central to ecology) and effective population size (N(e), a key parameter in evolutionary biology). Recent theoretical and numerical studies indicate that in semelparous species with variable age at maturity (such as Pacific salmon, many monocarpic plants, and various other species), differences in mean reproductive success among individuals reproducing in different years leads to variation in lambda, and this in turn can reduce N(e). However, this phenomenon has received little empirical evaluation. We examined time series of abundance data for 56 populations of chinook salmon (Onchorhynchus tshawytscha) from the northwestern United States and compared N(e) (calculated from demographic data) with the total number of spawners each generation (NT). Important results include: (1) The mean multigenerational ratio N(e)/N(T) was 0.64 (median = 0.67), indicating that annual variation in lambda reduces effective population size in chinook salmon by an average of approximately 35%. These reductions are independent of, and in addition to, factors that reduce N(e) within individual cohorts (uneven sex ratio and greater-than-random variance in reproductive success). (2) The coefficient of variation of lambda was the most important factor associated with reductions in N(e), explaining up to two-thirds of the variance in N(e)/N(T). (3) Within individual generations, N(e) was lower when there was a negative correlation between annual N(i) and lambda, i.e., when relatively few breeders produced relatively high numbers of offspring. Our results thus highlight an important and little-studied eco-evolutionary trade-off: density-dependent compensation has generally favorable ecological consequences (promoting stability and long-term viability) but incurs an evolutionary cost (reducing N(e) because a few individuals make a disproportionate genetic contribution). (4) For chinook salmon, N(eH) (an

  5. CTRP3 deficiency reduces liver size and alters IL-6 and TGFβ levels in obese mice.

    PubMed

    Wolf, Risa M; Lei, Xia; Yang, Zhi-Chun; Nyandjo, Maeva; Tan, Stefanie Y; Wong, G William

    2016-03-01

    C1q/TNF-related protein 3 (CTRP3) is a secreted metabolic regulator whose circulating levels are reduced in human and rodent models of obesity and diabetes. Previously, we showed that CTRP3 infusion lowers blood glucose by suppressing gluconeogenesis and that transgenic overexpression of CTRP3 protects mice against diet-induced hepatic steatosis. Here, we used a genetic loss-of-function mouse model to further address whether CTRP3 is indeed required for metabolic homeostasis under normal and obese states. Both male and female mice lacking CTRP3 had similar weight gain when fed a control low-fat (LFD) or high-fat diet (HFD). Regardless of diet, no differences were observed in adiposity, food intake, metabolic rate, energy expenditure, or physical activity levels between wild-type (WT) and Ctrp3-knockout (KO) animals of either sex. Contrary to expectations, loss of CTRP3 in LFD- or HFD-fed male and female mice also had minimal or no impact on whole body glucose metabolism, insulin sensitivity, and fasting-induced hepatic gluconeogenesis. Unexpectedly, the liver sizes of HFD-fed Ctrp3-KO male mice were markedly reduced despite a modest increase in triglyceride content. Furthermore, liver expression of fat oxidation genes was upregulated in the Ctrp3-KO mice. Whereas the liver and adipose expression of profibrotic TGFβ1, as well as its serum levels, was suppressed in HFD-fed KO mice, circulating proinflammatory IL-6 levels were markedly increased; these changes, however, were insufficient to affect systemic metabolic outcome. We conclude that, although it is dispensable for physiological control of energy balance, CTRP3 plays a previously unsuspected role in modulating liver size and circulating cytokine levels in response to obesity. PMID:26670485

  6. Is more better? Higher sterilization of infected hosts need not result in reduced pest population size.

    PubMed

    Maxin, Daniel; Berec, Luděk; Bingham, Adrienna; Molitor, Denali; Pattyson, Julie

    2015-05-01

    We analyze the effect of sterilization in the infected hosts in several epidemiological models involving infectious diseases that can be transmitted both vertically and horizontally. Sterilizing pathogens can be used as pest control agents by intentionally inoculating the target population, with the goal of reducing or eliminating it completely. Contrary to previous models that did not include vertical transmission we found that the population size at the endemic equilibrium may actually increase with higher levels of sterility. This effect is proved to exist for low to high efficiencies of vertical transmission. On the other hand, if the disease is sexually transmitted and the host reproduction and disease transmission are both consistently mediated by mating, we do not observe such a counter-intuitive effect and the population size in the stable endemic equilibrium is decreasing with higher levels of sterility. We suggest that models of the pest control techniques involving the release of sterilizing pathogens have to carefully consider the routes such pathogens use for transmission.

  7. Incorporating gold into nanocrystalline silver dressings reduces grain boundary size and maintains suitable antimicrobial properties.

    PubMed

    Unrau, Kevin R; Cavanagh, Marion H; Cheng, On Kwan; Wang, Shiman; Burrell, Robert E

    2013-12-01

    Nanocrystalline silver dressings are widely known to be potent antimicrobial and anti-inflammatory agents and have long been used to treat topical wounds. Gold is known to be a strong anti-inflammatory agent and has been used in the treatment of rheumatoid arthritis for >70 years. The purpose of this work was to study the effect of incorporating gold into nanocrystalline silver dressings from antimicrobial and anti-inflammatory perspectives. Gold and silver dressing alloys were created by direct current magnetron sputtering and compared with pure silver nanocrystalline dressings using conventional biological (log reduction and corrected zone of inhibition) and physical (X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, atomic absorption spectroscopy, atomic force microscopy and scanning electron microscopy) characterisation techniques. While the gold/silver dressings were slightly weaker antimicrobials than the pure silver nanocrystalline structures, the addition of gold to the nanostructure reduces the minimum crystallite size from 17 to 4 nm. This difference increases the number of grain boundary atoms from 12% to 40% which could augment the anti-inflammatory properties of the dressings. The formation of gold oxide (Au2O3) was thought to be responsible for the observed decrease in crystallite size.

  8. Xenoendocrine pollutants may reduce size of sexual organs in East Greenland polar bears (Ursus maritimus).

    PubMed

    Sonne, Christian; Leifsson, Pall S; Dietz, Rune; Born, Erik W; Letcher, Robert J; Hyldstrup, Lars; Riget, Frank F; Kirkegaard, Maja; Muir, Derek C G

    2006-09-15

    Reproductive organs from 55 male and 44 female East Greenland polar bears were examined to investigate the potential negative impact from organohalogen pollutants (OHCs). Multiple regressions normalizing for age showed a significant inverse relationship between OHCs and testis length and baculum length and weight, respectively, and was found in both subadults (dichlorodiphenyl trichloroethanes, dieldrin, chlordanes, hexacyclohexanes, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)) and adults (hexachlorobenzene [HCB]) (all p < 0.05). Baculum bone mineral densities decreased with increasing chlordanes, DDTs, and HCB in subadults and adults, respectively (all p < 0.05). In females, a significant inverse relationship was found between ovary length and sigma PCB (p = 0.03) and sigma CHL (p < 0.01), respectively, and between ovary weight and sigma PBDE (p < 0.01) and uterine horn length and HCB (p = 0.02). The study suggests thatthere is an impact from xenoendocrine pollutants on the size of East Greenland polar bear genitalia. This may pose a riskto this polar bear subpopulation in the future because of reduced sperm and egg quality/quantity and uterus and penis size/robustness.

  9. Somatostatin analogue, octreotide, reduces increased glomerular filtration rate and kidney size in insulin-dependent diabetes

    SciTech Connect

    Serri, O.; Beauregard, H.; Brazeau, P.; Abribat, T.; Lambert, J.; Harris, A.; Vachon, L. Sandoz Canada Inc., Dorval, Quebec )

    1991-02-20

    To determine whether treatment with a somatostatin analogue can reduce kidney hyperfiltration and hypertrophy in insulin-dependent diabetes mellitus, the authors studied 11 patients with insulin-dependent diabetes mellitus and glomerular hyperfiltration. The patients were assigned randomly to receive continuous subcutaneous infusion of either octreotide, 300 {mu}g/24 h (five patients) or placebo (six patients) for 12 weeks. At baseline, mean glomerular filtration rate and mean total kidney volume were not significantly different in the two groups. However, after 12 weeks of treatment, the mean glomerular filtration rate was significantly lower in the octreotide group than in the placebo group. Furthermore, the mean total kidney volume was significantly lower after treatment in the octreotide group than in the placebo group. Glycemic control did not change significantly in either group. They conclude that subcutaneous infusion of octreotide for 12 weeks reduces increased glomerular filtration rate and kidney size in patients with insulin-dependent diabetes mellitus despite the fact that glycemic control remains unchanged.

  10. Reduced salivary gland size and increased presence of epithelial progenitor cells in DLK1-deficient mice.

    PubMed

    García-Gallastegui, P; Luzuriaga, J; Aurrekoetxea, M; Baladrón, V; Ruiz-Hidalgo, M J; García-Ramírez, J J; Laborda, J; Unda, F; Ibarretxe, G

    2016-06-01

    DLK1 (PREF1, pG2, or FA1) is a transmembrane and secreted protein containing epidermal growth factor-like repeats. Dlk1 expression is abundant in many tissues during embryonic and fetal development and is believed to play an important role in the regulation of tissue differentiation and fetal growth. After birth, Dlk1 expression is abolished in most tissues but is possibly reactivated to regulate stem cell activation and responses to injury. We have recently reported that DLK1 regulates many aspects of salivary gland organogenesis. Here, we have extended our studies of the salivary gland phenotype of Dlk1 knock-out mice. We have observed that salivary glands are smaller and weigh significantly less in both Dlk1 knock-out males and females compared with gender and age-matched wild-type mice and regardless of the natural sexual dimorphism in rodent salivary glands. This reduced size correlates with a reduced capacity of Dlk1-deficient mice to secrete saliva after stimulation with pilocarpine. However, histological and ultrastructural analyses of both adult and developing salivary gland tissues have revealed no defects in Dlk1 ((-/-)) mice, indicating that genetic compensation accounts for the relatively mild salivary phenotype in these animals. Finally, despite their lack of severe anomalies, we have found that salivary glands from Dlk1-deficient mice present a higher amount of CK14-positive epithelial progenitors at various developmental stages, suggesting a role for DLK1 in the regulation of salivary epithelial stem cell balance.

  11. Restaurant Owners’ Perspectives on a Voluntary Program to Recognize Restaurants for Offering Reduced-Size Portions, Los Angeles County, 2012

    PubMed Central

    Dunning, Lauren; Kuo, Tony; Simon, Paul; Fielding, Jonathan E.

    2014-01-01

    Introduction Reducing the portion size of food and beverages served at restaurants has emerged as a strategy for addressing the obesity epidemic; however, barriers and facilitators to achieving this goal are not well characterized. Methods In fall 2012, the Los Angeles County Department of Public Health conducted semistructured interviews with restaurant owners to better understand contextual factors that may impede or facilitate participation in a voluntary program to recognize restaurants for offering reduced-size portions. Results Interviews were completed with 18 restaurant owners (representing nearly 350 restaurants). Analyses of qualitative data revealed 6 themes related to portion size: 1) perceived customer demand is central to menu planning; 2) multiple portion sizes are already being offered for at least some food items; 3) numerous logistical barriers exist for offering reduced-size portions; 4) restaurant owners have concerns about potential revenue losses from offering reduced-size portions; 5) healthful eating is the responsibility of the customer; and 6) a few owners want to be socially responsible industry leaders. Conclusion A program to recognize restaurants for offering reduced-size portions may be a feasible approach in Los Angeles County. These findings may have applications for jurisdictions interested in engaging restaurants as partners in reducing the obesity epidemic. PMID:24650622

  12. Handling large datasets of hyperspectral images: reducing data size without loss of useful information.

    PubMed

    Ferrari, Carlotta; Foca, Giorgia; Ulrici, Alessandro

    2013-11-13

    Hyperspectral Imaging (HSI) is gaining increasing interest in the field of analytical chemistry, since this fast and non-destructive technique allows one to easily acquire a large amount of spectral and spatial information on a wide number of samples in very short times. However, the large size of hyperspectral image data often limits the possible uses of this technique, due to the difficulty of evaluating many samples altogether, for example when one needs to consider a representative number of samples for the implementation of on-line applications. In order to solve this problem, we propose a novel chemometric strategy aimed to significantly reduce the dataset size, which allows to analyze in a completely automated way from tens up to hundreds of hyperspectral images altogether, without losing neither spectral nor spatial information. The approach essentially consists in compressing each hyperspectral image into a signal, named hyperspectrogram, which is created by combining several quantities obtained by applying PCA to each single hyperspectral image. Hyperspectrograms can then be used as a compact set of descriptors and subjected to blind analysis techniques. Moreover, a further improvement of both data compression and calibration/classification performances can be achieved by applying proper variable selection methods to the hyperspectrograms. A visual evaluation of the correctness of the choices made by the algorithm can be obtained by representing the selected features back into the original image domain. Likewise, the interpretation of the chemical information underlying the selected regions of the hyperspectrograms related to the loadings is enabled by projecting them in the original spectral domain. Examples of applications of the hyperspectrogram-based approach to hyperspectral images of food samples in the NIR range (1000-1700 nm) and in the vis-NIR range (400-1000 nm), facing a calibration and a defect detection issue respectively, demonstrate the

  13. [Aortic thrombus and splenic infarcts indicating essential thrombocythemia].

    PubMed

    Bachmeyer, C; Elalamy, I

    2011-09-01

    Essential thrombocythemia is a myeloproliferative disorder responsible for both hemorrhagic and thrombotic complications mostly venous but also arterial, especially of the microcirculation. We report a 64-year-old female who presented with an aortic thrombus and splenic infarcts indicating essential thrombocythemia. Outcome was favourable with medical treatment combining low-molecular-weight heparin secondarily switched to warfarin, associated with aspirin and hydroxyurea.

  14. Calcified right atrial thrombus in HIV infected patient

    PubMed Central

    Mwita, Julius Chacha; Goepamang, Monkgogi; Mkubwa, Jack Joseph; Gunness, Teeluck Kumar; Reebye, Deshmukh; Motumise, Kelebogile

    2013-01-01

    Calcified right atrial thrombi are rare cardiac masses that may be complicated by pulmonary embolism. Although they can be discovered by a transthoracic echocardiography, they may need histological examination to differentiate them from other cardiac masses. We report a case of a 44-year-old woman who presented with a calcified right atrial thrombus and progressive dyspnoea. PMID:23819008

  15. Thrombus formation induced by laser in a mouse model

    PubMed Central

    PÉREZ, PABLO; ALARCÓN, MARCELO; FUENTES, EDUARDO; PALOMO, IVÁN

    2014-01-01

    Animal models are used for the development of techniques and/or models that aid the study of thrombosis pathophysiology. The aim of the present study was to modify the technique of in vivo thrombosis induction to make it more accessible. BALB/c mice were intraperitoneally anesthetized with 0.4 ml 2,2,2-tribromoethanol (266.6 mg/kg) and xylazine (13.3 mg/kg), whilst maintaining stable blood pressure and temperature. Through abdominal surgery, the mesentery was identified and isolated for the visualization of the arteries. A simple epifluorescence magnifier was used to detect the presence of thrombi. The results obtained indicate that using rose bengal at concentrations of 25 and 50 mg/kg and a laser power of 5 mW, thrombus formation occurred. In addition, formation of the thrombus occurred ~30 min following induction and the thrombus had a total area of 4,878.3 μm2, which caused total occlusion of the mesenteric artery. For visualization, platelets were labeled with calcein acetyloxymethyl ester for 1 h, which resulted in improved observation of thrombus formation in real time. Therefore, this technique may be used to perform in vivo studies simply and at low cost, and is suitable for use in a variety of studies of thrombosis. PMID:24944598

  16. A Predictive Model of High Shear Thrombus Growth.

    PubMed

    Mehrabadi, Marmar; Casa, Lauren D C; Aidun, Cyrus K; Ku, David N

    2016-08-01

    The ability to predict the timescale of thrombotic occlusion in stenotic vessels may improve patient risk assessment for thrombotic events. In blood contacting devices, thrombosis predictions can lead to improved designs to minimize thrombotic risks. We have developed and validated a model of high shear thrombosis based on empirical correlations between thrombus growth and shear rate. A mathematical model was developed to predict the growth of thrombus based on the hemodynamic shear rate. The model predicts thrombus deposition based on initial geometric and fluid mechanic conditions, which are updated throughout the simulation to reflect the changing lumen dimensions. The model was validated by comparing predictions against actual thrombus growth in six separate in vitro experiments: stenotic glass capillary tubes (diameter = 345 µm) at three shear rates, the PFA-100(®) system, two microfluidic channel dimensions (heights = 300 and 82 µm), and a stenotic aortic graft (diameter = 5.5 mm). Comparison of the predicted occlusion times to experimental results shows excellent agreement. The model is also applied to a clinical angiography image to illustrate the time course of thrombosis in a stenotic carotid artery after plaque cap rupture. Our model can accurately predict thrombotic occlusion time over a wide range of hemodynamic conditions.

  17. Using Ancillary Information to Reduce Sample Size in Discovery Sampling and the Effects of Measurement Error

    SciTech Connect

    Axelrod, M

    2005-08-18

    big sample size might bust the budget, or the number seems intuitively excessive. To reduce the sample size, you can increase the tolerable number of defectives, the ''10'' in the preceding example, or back off on the confidence level, say from 95% to 90%. Auditors also frequently bump up the sample size as a safety factor. They know that something can go wrong. For example, they might find out that the measurements or inspections were subject to errors. Unless the auditors know exactly how measurement error affects sample size, they might be forced to give up the safety factor. Clients often choose to ''live dangerously'' (without a compelling argument to the contrary) to save money. Thus, sometimes the auditor finds that ''you just can't get there from here'', because the goals of the audit and the resources available are inherently in conflict. For discovery audits, there is a way out of this apparent conundrum. It turns out that the classical method of confidence intervals uses an implicit and very conservative assumption. We will see that this assumption is too pessimistic and too conservative in the context of a discovery audit. If we abandon this assumption and use ancillary information about the inventory, then we can significantly reduce the sample size required to achieve the desired confidence level. We will see exactly how the classical method ignores this ancillary information and misses the opportunity for an efficient audit. In the following sections, we first review the standard approach using confidence intervals. Then we present a method that incorporates the ancillary information about the inventory to design a very efficient discovery audit. We also provide results on how measurement errors affect the audit, and how exactly how much the sample size must be modified to compensate for these errors. Finally, we state asymptotic formulas that provide useful approximations for large inventories. It is suggested that the reader review the glossary of

  18. Reduced salivary gland size and increased presence of epithelial progenitor cells in DLK1-deficient mice.

    PubMed

    García-Gallastegui, P; Luzuriaga, J; Aurrekoetxea, M; Baladrón, V; Ruiz-Hidalgo, M J; García-Ramírez, J J; Laborda, J; Unda, F; Ibarretxe, G

    2016-06-01

    DLK1 (PREF1, pG2, or FA1) is a transmembrane and secreted protein containing epidermal growth factor-like repeats. Dlk1 expression is abundant in many tissues during embryonic and fetal development and is believed to play an important role in the regulation of tissue differentiation and fetal growth. After birth, Dlk1 expression is abolished in most tissues but is possibly reactivated to regulate stem cell activation and responses to injury. We have recently reported that DLK1 regulates many aspects of salivary gland organogenesis. Here, we have extended our studies of the salivary gland phenotype of Dlk1 knock-out mice. We have observed that salivary glands are smaller and weigh significantly less in both Dlk1 knock-out males and females compared with gender and age-matched wild-type mice and regardless of the natural sexual dimorphism in rodent salivary glands. This reduced size correlates with a reduced capacity of Dlk1-deficient mice to secrete saliva after stimulation with pilocarpine. However, histological and ultrastructural analyses of both adult and developing salivary gland tissues have revealed no defects in Dlk1 ((-/-)) mice, indicating that genetic compensation accounts for the relatively mild salivary phenotype in these animals. Finally, despite their lack of severe anomalies, we have found that salivary glands from Dlk1-deficient mice present a higher amount of CK14-positive epithelial progenitors at various developmental stages, suggesting a role for DLK1 in the regulation of salivary epithelial stem cell balance. PMID:26711912

  19. Prediction of thrombus-related mechanical prosthetic valve dysfunction using transesophageal echocardiography

    NASA Technical Reports Server (NTRS)

    Lin, S. S.; Tiong, I. Y.; Asher, C. R.; Murphy, M. T.; Thomas, J. D.; Griffin, B. P.

    2000-01-01

    Identification of thrombus-related mechanical prosthetic valve dysfunction (MPVD) has important therapeutic implications. We sought to develop an algorithm, combining clinical and echocardiographic parameters, for prediction of thrombus-related MPVD in a series of 53 patients (24 men, age 52 +/- 16 years) who had intraoperative diagnosis of thrombus or pannus from 1992 to 1997. Clinical and echocardiographic parameters were analyzed to identify predictors of thrombus and pannus. Prevalence of thrombus and diagnostic yields relative to the number of predictors were determined. There were 22 patients with thrombus, 19 patients with pannus, and 12 patients with both. Forty-two of 53 masses were visualized using transesophageal echocardiography (TEE), including 29 of 34 thrombi or both thrombi and panni and 13 of 19 isolated panni. Predictors of thrombus or mixed presentation include mobile mass (p = 0.009), attachment to occluder (p = 0.02), elevated gradients (p = 0.04), and an international normalized ratio of < or = 2.5 (p = 0.03). All 34 patients with thrombus or mixed presentation had > or = 1 predictor. The prevalence of thrombus in the presence of < or = 1, 2, and > or = 3 predictors is 14%, 69%, and 91%, respectively. Thus, TEE is sensitive in the identification of abnormal mass in the setting of MPVD. An algorithm based on clinical and transesophageal echocardiographic predictors may be useful to estimate the likelihood of thrombus in the setting of MPVD. In the presence of > or = 3 predictors, the probability of thrombus is high.

  20. Prediction of thrombus-related mechanical prosthetic valve dysfunction using transesophageal echocardiography.

    PubMed

    Lin, S S; Tiong, I Y; Asher, C R; Murphy, M T; Thomas, J D; Griffin, B P

    2000-11-15

    Identification of thrombus-related mechanical prosthetic valve dysfunction (MPVD) has important therapeutic implications. We sought to develop an algorithm, combining clinical and echocardiographic parameters, for prediction of thrombus-related MPVD in a series of 53 patients (24 men, age 52 +/- 16 years) who had intraoperative diagnosis of thrombus or pannus from 1992 to 1997. Clinical and echocardiographic parameters were analyzed to identify predictors of thrombus and pannus. Prevalence of thrombus and diagnostic yields relative to the number of predictors were determined. There were 22 patients with thrombus, 19 patients with pannus, and 12 patients with both. Forty-two of 53 masses were visualized using transesophageal echocardiography (TEE), including 29 of 34 thrombi or both thrombi and panni and 13 of 19 isolated panni. Predictors of thrombus or mixed presentation include mobile mass (p = 0.009), attachment to occluder (p = 0.02), elevated gradients (p = 0.04), and an international normalized ratio of < or = 2.5 (p = 0.03). All 34 patients with thrombus or mixed presentation had > or = 1 predictor. The prevalence of thrombus in the presence of < or = 1, 2, and > or = 3 predictors is 14%, 69%, and 91%, respectively. Thus, TEE is sensitive in the identification of abnormal mass in the setting of MPVD. An algorithm based on clinical and transesophageal echocardiographic predictors may be useful to estimate the likelihood of thrombus in the setting of MPVD. In the presence of > or = 3 predictors, the probability of thrombus is high. PMID:11074206

  1. Epigenetic Upregulation of Endogenous VEGF-A Reduces Myocardial Infarct Size in Mice

    PubMed Central

    Musthafa, Haja; Laidinen, Svetlana; Dragneva, Galina; Laham-Karam, Nihay; Honkanen, Sanna; Paakinaho, Anne; Laakkonen, Johanna P.; Gao, Erhe; Vihinen-Ranta, Maija; Liimatainen, Timo; Ylä-Herttuala, Seppo

    2014-01-01

    “Epigenetherapy” alters epigenetic status of the targeted chromatin and modifies expression of the endogenous therapeutic gene. In this study we used lentiviral in vivo delivery of small hairpin RNA (shRNA) into hearts in a murine infarction model. shRNA complementary to the promoter of vascular endothelial growth factor (VEGF-A) was able to upregulate endogenous VEGF-A expression. Histological and multiphoton microscope analysis confirmed the therapeutic effect in the transduced hearts. Magnetic resonance imaging (MRI) showed in vivo that the infarct size was significantly reduced in the treatment group 14 days after the epigenetherapy. Importantly, we show that promoter-targeted shRNA upregulates all isoforms of endogenous VEGF-A and that an intact hairpin structure is required for the shRNA activity. In conclusion, regulation of gene expression at the promoter level is a promising new treatment strategy for myocardial infarction and also potentially useful for the upregulation of other endogenous genes. PMID:24587164

  2. From micro- to nanomagnetic dots: evolution of the eigenmode spectrum on reducing the lateral size

    NASA Astrophysics Data System (ADS)

    Carlotti, G.; Gubbiotti, G.; Madami, M.; Tacchi, S.; Hartmann, F.; Emmerling, M.; Kamp, M.; Worschech, L.

    2014-07-01

    Brillouin light scattering experiments and micromagnetic simulations have been exploited to investigate the spectrum of thermally excited magnetic eigenmodes in 10 nm-thick elliptical Permalloy dots, when the longer axis D is scaled down from about 1000 to 100 nm. It is shown that for D larger than about 200 nm the characteristics of the spin-wave eigenmodes are dominated by dipolar energy, while for D in the range of about 100 to 200 nm exchange energy effects cause qualitative and quantitative differences in the spin-wave spectrum. In this ‘mesoscopic’ regime, the usual classification scheme, involving one fundamental mode with large average magnetization and many other modes collected in families with specific symmetries, no longer holds. Rather, one finds the simultaneous presence of two modes with ‘fundamental’ character, i.e. with a significant and comparable value of the average dynamical magnetization: the former is at larger frequency and has its maximum amplitude at the dot's centre, while the latter occurs at lower frequency and is localized at the dot's edges. Interestingly, the maximum intensity swaps from the higher frequency mode to the lower frequency one, just when the dot size is reduced from about 200 to 100 nm. This is relevant in view of the exploitation of nanodots for the design of nanomagnetic devices with lateral dimensions in the above interval, such as memory cells, logic gates, reading heads and spin-torque oscillators.

  3. Pentoxifylline does not reduce infarct size in a canine model of acute myocardial infarction.

    PubMed Central

    Campbell, C. A.; Clavenna, C. F.; Wynne, J.; Kloner, R. A.

    1988-01-01

    1. The effect of the haemorrheological agent pentoxifylline was investigated in a canine model of acute myocardial infarction, induced by occlusion of the left anterior descending coronary for 6 h. Thirty minutes post-occlusion the dogs were randomized to receive either distilled water or pentoxifylline (0.3 mg kg-1 min-1 for 1 h followed by 0.15 mg kg-1 min-1 for 4.5 h) intravenously. 2. At 6 h post-occlusion the in vivo area at risk was determined with monastral blue dye and the area of necrosis was determined with triphenyltetrazolium chloride. The area at risk was 16.5 +/- 1.3% in the control group (n = 10) and 17.2 +/- 1.8% in the pentoxifylline treated group (n = 10; NS). The area of necrosis was 12.3 +/- 1.9% in the control group and 11.9 +/- 2.2% in the pentoxifylline treated group (NS). The area of necrosis expressed as a percentage of the area at risk was 69.3 +/- 7.7% in the control group and 63.6 +/- 7.4% in the pentoxifylline treated group (NS). 3. Pentoxifylline had no significant effects on heart rate, systolic or diastolic blood pressure. Regional myocardial blood flow, measured by the radioactive microsphere technique, was not significantly different between the groups. 4. Thus, pentoxifylline does not reduce infarct size in this model of acute myocardial infarction and does not enhance coronary collateral blood flow. PMID:3370389

  4. The effect of factor VIII deficiencies and replacement and bypass therapies on thrombus formation under venous flow conditions in microfluidic and computational models.

    PubMed

    Onasoga-Jarvis, Abimbola A; Leiderman, Karin; Fogelson, Aaron L; Wang, Michael; Manco-Johnson, Marilyn J; Di Paola, Jorge A; Neeves, Keith B

    2013-01-01

    Clinical evidence suggests that individuals with factor VIII (FVIII) deficiency (hemophilia A) are protected against venous thrombosis, but treatment with recombinant proteins can increase their risk for thrombosis. In this study we examined the dynamics of thrombus formation in individuals with hemophilia A and their response to replacement and bypass therapies under venous flow conditions. Fibrin and platelet accumulation were measured in microfluidic flow assays on a TF-rich surface at a shear rate of 100 s⁻¹. Thrombin generation was calculated with a computational spatial-temporal model of thrombus formation. Mild FVIII deficiencies (5-30% normal levels) could support fibrin fiber formation, while severe (<1%) and moderate (1-5%) deficiencies could not. Based on these experimental observations, computational calculations estimate an average thrombin concentration of ∼10 nM is necessary to support fibrin formation under flow. There was no difference in fibrin formation between severe and moderate deficiencies, but platelet aggregate size was significantly larger for moderate deficiencies. Computational calculations estimate that the local thrombin concentration in moderate deficiencies is high enough to induce platelet activation (>1 nM), but too low to support fibrin formation (<10 nM). In the absence of platelets, fibrin formation was not supported even at normal FVIII levels, suggesting platelet adhesion is necessary for fibrin formation. Individuals treated by replacement therapy, recombinant FVIII, showed normalized fibrin formation. Individuals treated with bypass therapy, recombinant FVIIa, had a reduced lag time in fibrin formation, as well as elevated fibrin accumulation compared to healthy controls. Treatment of rFVIIa, but not rFVIII, resulted in significant changes in fibrin dynamics that could lead to a prothrombotic state. PMID:24236042

  5. 30 CFR 203.76 - When might MMS withdraw or reduce the approved size of my relief?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false When might MMS withdraw or reduce the approved... Development and Expansion Projects § 203.76 When might MMS withdraw or reduce the approved size of my relief... system within18 months of the date we approved your application, unless the MMS Director grants you...

  6. Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

    PubMed Central

    Walzer, Andreas; Schausberger, Peter

    2013-01-01

    Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Conclusions/Significance Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism – females are the larger sex and thus more strongly affected by maternal stress than the smaller males – and to sexually selected lower plasticity of male body size. PMID:24265745

  7. Real-Time Observation of Thrombus Growth Process in an Impeller of a Hydrodynamically Levitated Centrifugal Blood Pump by Near-Infrared Hyperspectral Imaging.

    PubMed

    Sakota, Daisuke; Murashige, Tomotaka; Kosaka, Ryo; Fujiwara, Tatsuki; Nishida, Masahiro; Maruyama, Osamu

    2015-08-01

    Understanding the thrombus formation in cardiovascular devices such as rotary blood pumps is the most important issue in developing more hemocompatible devices. The objective of this study was to develop a hyperspectral imaging (HSI) method to visualize the thrombus growth process within a rotary blood pump and investigate the optical properties of the thrombus. An in vitro thrombogenic test was conducted using fresh porcine blood and a specially designed hydrodynamically levitated centrifugal blood pump with a transparent bottom. The pump rotating at 3000 rpm circulated the blood at 1.0 L/min. The bottom surface of the pump was illuminated with white light pulsed at the same frequency as the pump rotation, and the backward-scattered light was imaged using the HSI system. Using stroboscopic HSI and an image construction algorithm, dynamic spectral imaging at wavelengths ranging from 608 to 752 nm within the rotating pump was achieved. After completing the experiment, we collected the red thrombus formed in the pump impeller and quantified the thrombus hemoglobin concentration (Hbthrombus ). The spectrum changed around the center of the impeller, and the area of change expanded toward the impeller flow path. The shape corresponded approximately to the shape of the thrombus. The spectrum change indicated that the light scattering derived from red blood cells decreased. The Hbthrombus was 4.7 ± 1.3 g/dL versus a total hemoglobin of 13 ± 0.87 g/dL. The study revealed that Hbthrombus was reduced by the surrounding blood flow.

  8. Treatment with the gap junction modifier rotigaptide (ZP123) reduces infarct size in rats with chronic myocardial infarction.

    PubMed

    Haugan, Ketil; Marcussen, Niels; Kjølbye, Anne Louise; Nielsen, Morten Schak; Hennan, James K; Petersen, Jørgen Søberg

    2006-02-01

    Treatment with non-selective drugs (eg, long-chain alcohols, halothane) that reduce gap junction intercellular communication (GJIC) is associated with reduced infarct size after myocardial infarction (MI). Therefore, it has been suggested that gap junction intercellular communication stimulating compounds may increase infarct size. The antiarrhythmic peptide analogue rotigaptide (ZP123) increases cardiac gap junction intercellular communication and the purpose of the present study was to examine the effects of rotigaptide treatment on infarct size. Myocardial infarction was induced in male rats by ligation of the left anterior descending artery (LAD). Rats (n = 156) were treated with rotigaptide at three dose levels or vehicle from the onset of ischemia and for 3 weeks following LAD occlusion. Infarct size was determined using histomorphometry after 3 weeks treatment. Rotigaptide treatment producing steady state plasma levels of 0.8 +/- 0.1, 5.5 +/- 0.5, and 86 +/- 8 nmol/L had no effect on mortality, but reduced infarct size to 90 +/- 10% (P = 0.41), 67 +/- 7% (P = 0.005), and 82 +/- 7% (P = 0.13), respectively relative to vehicle-treated myocardial infarction rats (100 +/- 12%). In contrast to what was predicted, our data demonstrates that rotigaptide treatment was associated with a significant infarct size reduction. We conclude that whereas treatment with non-selective inhibitors of gap junction intercellular communication cause a reduction in infarct size, this information cannot be extrapolated to the effects of compounds that selectively increase gap junction intercellular communication.

  9. Ecological constraints on sensory systems: compound eye size in Daphnia is reduced by resource limitation.

    PubMed

    Brandon, Christopher S; Dudycha, Jeffry L

    2014-08-01

    Eye size is an indicator of visual capability, and macroevolutionary patterns reveal that taxa inhabiting dim environments have larger eyes than taxa from bright environments. This suggests that the light environment is a key driver of variation in eye size. Yet other factors not directly linked with visual tasks (i.e., non-sensory factors) may influence eye size. We sought to jointly investigate the roles of sensory (light) and non-sensory factors (food) in determining eye size and ask whether non-sensory factors could constrain visual capabilities. We tested environmental influences on eye size in four species of the freshwater crustacean Daphnia, crossing bright and dim light levels with high and low resource levels. We measured absolute eye size and eye size relative to body size in early and late adulthood. In general, Daphnia reared on low resources had smaller eyes, both absolutely and relatively. In contrast to the dominant macroevolutionary pattern, phenotypic plasticity in response to light was rarely significant. These patterns of phenotypic plasticity were true for overall diameter of the eye and the diameter of individual facets. We conclude that non-sensory environmental factors can influence sensory systems, and in particular, that resource availability may be an important constraint on visual capability.

  10. Reducing Class Size: A Smart Way To Improve America's Urban Schools. Second Edition.

    ERIC Educational Resources Information Center

    Naik, Manish; Casserly, Michael; Uro, Gabriela

    The Council of the Great City Schools, a coalition of the largest urban public schools in the United States, surveyed its membership to determine how they were using federal class size reduction funds in the 2000-2001 school year. Thirty-six major urban school systems responded. Results indicate that the federal class size reduction program is…

  11. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    PubMed Central

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-01-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms. PMID:27677245

  12. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    NASA Astrophysics Data System (ADS)

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-09-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms.

  13. Intraventricular brain-derived neurotrophic factor reduces infarct size after focal cerebral ischemia in rats.

    PubMed

    Schäbitz, W R; Schwab, S; Spranger, M; Hacke, W

    1997-05-01

    Brain-derived neurotrophic factor (BDNF), acting through the high-affinity receptor tyrosine kinase (TrkB), is widely distributed throughout the central nervous system and displays in vitro trophic effects on a wide range of neuronal cells, including hippocampal, cerebellar, and cortical neurons. In vivo, BDNF rescues motorneurons, hippocampal, and substantia nigral dopaminergic cells from traumatic and toxic brain injury. After transient middle cerebral artery occlusion (MCAO), upregulation of BDNF-mRNA in cortical neurons suggests that BDNF potentially plays a neuroprotective role in focal cerebral ischemia. In the current study, BDNF (2.1 micrograms/d) in vehicle or vehicle alone (controls) was delivered intraventricularly for 8 days, beginning 24 hours before permanent middle cerebral artery occlusion by intraluminal suture in Wistar rats (n = 13 per group). There were no differences in physiological variables recorded during surgery for the two groups. Neurological deficit (0 to 4 scale), which was assessed on a daily basis, improved in BDNF-treated animals compared with controls (P < 0.05; analysis of variance and Scheffe's test). There were no significant differences in weight in BDNF-treated animals and controls during the experiment. After elective killing on day 7 after MCAO, brains underwent 2,3,5-triphenyltetrazolium chloride staining for calculation of the infarct volume and for histology (hematoxylin and eosin and glial fibrillary acid protein). The mean total infarct volume was 83.1 +/- 27.1 mm3 in BDNF-treated animals and 139.2 +/- 56.4 mm3 in controls (mean +/- SD; P < 0.01, unpaired, two-tailed t-test). The cortical infarct volume was 10.8 +/- 7.1 mm3 in BDNF-treated animals and 37.9 +/- 19.8 mm3 in controls (mean +/- SD; P < 0.05; unpaired, two-tailed t-test), whereas ischemic lesion volume in caudoputaminal infarction was not significantly different. These results show that pretreatment with intraventricular BDNF reduces infarct size after focal

  14. Cardiac Fibroelastoma versus Thrombus: Echocardiographic Evidence Can Be Misleading

    PubMed Central

    2016-01-01

    We present a case of a young female with stroke symptoms who underwent valve sparing resection of a presumed fibroelastoma based on echocardiographic findings. After confirming embolic stroke, she underwent excision of the lesion, which on pathology revealed a nonbacterial thrombus. Ultimately, this led to a more extensive work-up leading to the discovery of a papillary serous ovarian carcinoma, the underlying cause of her hypercoagulable state. The initial echocardiographic findings painted the clear picture of a papillary tumor on the aortic valve which was likely the source of the emboli resulting in ischemic stroke. This unique case presentation illustrates that imaging, including echocardiography, may not always coincide with the clinical diagnosis. Thus, understanding the differential diagnoses of cardiac masses is of vital clinical significance. The distinction of fibroelastoma versus the much less common finding of aortic thrombus may lead to early diagnosis of malignancy and prevention of life threatening events due to stroke or undiagnosed disease. PMID:27547468

  15. Thrombus Volume Change Visualization after Endovascular Abdominal Aortic Aneurysm Repair

    NASA Astrophysics Data System (ADS)

    Maiora, Josu; García, Guillermo; Macía, Iván; Legarreta, Jon Haitz; Boto, Fernando; Paloc, Céline; Graña, Manuel; Abuín, Javier Sanchez

    A surgical technique currently used in the treatment of Abdominal Aortic Aneurysms (AAA) is the Endovascular Aneurysm Repair (EVAR). This minimally invasive procedure involves inserting a prosthesis in the aortic vessel that excludes the aneurysm from the bloodstream. The stent, once in place acts as a false lumen for the blood current to travel down, and not into the surrounding aneurysm sac. This procedure, therefore, immediately takes the pressure off the aneurysm, which thromboses itself after some time. Nevertheless, in a long term perspective, different complications such as prosthesis displacement or bloodstream leaks into or from the aneurysmatic bulge (endoleaks) could appear causing a pressure elevation and, as a result, increasing the danger of rupture. The purpose of this work is to explore the application of image registration techniques to the visual detection of changes in the thrombus in order to assess the evolution of the aneurysm. Prior to registration, both the lumen and the thrombus are segmented

  16. Coagulation activity and white thrombus formation in the microminipig.

    PubMed

    Miura, Naoki; Kawaguchi, Hiroaki; Nagasato, Tomoka; Yamada, Tomonobu; Ito, Takashi; Izumi, Hiroyuki; Shameshima, Hisayo; Miyoshi, Noriaki; Tanimoto, Akihide; Maruyama, Ikuro

    2013-01-01

    Swine are becoming increasingly attractive as animal models for clinical research and the recently developed Microminipig (MMPig) has emerged as a possible experimental animal model. In this study, we demonstrated age-dependent changes in hematological parameters and coagulation activity in healthy MMPigs (58 male and 67 females, aged 0-34 months), and investigated white thrombus formation (WTF) using an in vitro microchip flow-chamber system (four males and four females, aged 22-23 months). There was no clear sex or age-dependent differences in any hematological parameters. While activated partial thromboplastin time (APTT) was shorter than prothrombin time (PT), with APTT:PT of 0.88:1, microchip flow-chamber system analysis showed that WTF time was shorter than that in humans, suggesting a possible thrombotic tendency in the MMPig. These results could be useful to life science researchers in the use of the MMPig as an experimental model animal for thrombus formation. PMID:23606691

  17. Platelet PECAM-1 inhibits thrombus formation in vivo.

    PubMed

    Falati, Shahrokh; Patil, Sonali; Gross, Peter L; Stapleton, Michelle; Merrill-Skoloff, Glenn; Barrett, Natasha E; Pixton, Katherine L; Weiler, Harmut; Cooley, Brian; Newman, Debra K; Newman, Peter J; Furie, Barbara C; Furie, Bruce; Gibbins, Jonathan M

    2006-01-15

    Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell surface glycoprotein receptor expressed on a range of blood cells, including platelets, and on vascular endothelial cells. PECAM-1 possesses adhesive and signaling properties, the latter being mediated by immunoreceptor tyrosine-based inhibitory motifs present on the cytoplasmic tail of the protein. Recent studies in vitro have demonstrated that PECAM-1 signaling inhibits the aggregation of platelets. In the present study we have used PECAM-1-deficient mice and radiation chimeras to investigate the function of this receptor in the regulation of thrombus formation. Using intravital microscopy and laser-induced injury to cremaster muscle arterioles, we show that thrombi formed in PECAM-1-deficient mice were larger, formed more rapidly than in control mice, and were more stable. Larger thrombi were also formed in control mice that received transplants of PECAM-1-deficient bone marrow, in comparison to mice that received control transplants. A ferric chloride model of thrombosis was used to investigate thrombus formation in carotid arteries. In PECAM-1-deficient mice the time to 75% vessel occlusion was significantly shorter than in control mice. These data provide evidence for the involvement of platelet PECAM-1 in the negative regulation of thrombus formation. PMID:16166583

  18. Protein disulfide isomerase capture during thrombus formation in vivo depends on the presence of β3 integrins.

    PubMed

    Cho, Jaehyung; Kennedy, Daniel R; Lin, Lin; Huang, Mingdong; Merrill-Skoloff, Glenn; Furie, Barbara C; Furie, Bruce

    2012-07-19

    Extracellular protein disulfide isomerase (PDI) is required for platelet thrombus formation and fibrin generation after arteriolar wall injury in live mice. PDI is secreted from platelets and endothelial cells on cellular activation, but the mechanism of capture of secreted PDI within the injured vasculature is unknown. We establish that, like the endothelial β3 integrin α(V)β(3), the platelet integrin α(IIb)β(3) binds PDI. PDI also binds to recombinant β3. Using intravital microscopy, we demonstrate that PDI accumulation at the site of laser-induced arteriolar wall injury is markedly reduced in β3-null (β3(-/-)) mice, and neither a platelet thrombus nor fibrin is generated at the vessel injury site. The absence of fibrin after vascular injury in β3(-/-) mice is because of the absence of extracellular PDI. To evaluate the relative importance of endothelial α(V)β(3) versus platelet α(IIb)β(3) or α(V)β(3), we performed reciprocal bone marrow transplants on wild-type and β3(-/-) mice. PDI accumulation and platelet thrombus formation were markedly decreased after vessel injury in wild-type mice transplanted with β3(-/-) bone marrow or in β3(-/-) mice transplanted with wild-type bone marrow. These results indicate that both endothelial and platelet β3 integrins contribute to extracellular PDI binding at the vascular injury site.

  19. [Survival after Sorafenib Treatment for Advanced Recurrent Hepatocellular Carcinoma with Tumor Thrombus in the Inferior Vena Cava].

    PubMed

    Matoba, Hideaki; Seta, Shinsuke

    2015-11-01

    A 72-year-old man with chronic viral hepatitis type B undergoing surgery for hepatocellular carcinoma was found to have a recurrent tumor in the left liver with peritoneal dissemination near the inferior vena cava(IVC)and tumor thrombus in the IVC. For this patient diagnosed with Barcelona clinic liver cancer (BCLC) classification stage C hepatocellular carcinoma, we initiated 800 mg/body sorafenib. Two weeks after the initiation of sorafenib, the patient experienced grade 3 hand-foot syndrome, after which, the dose of sorafenib was reduced to 400 mg/body. After 1 year, CT showed an enlarged tumor in the left liver and multiple metastases to the lung. However, no remarkable difference was observed in the peritoneal dissemination and the tumor thrombus. He has been receiving sorafenib for 19 months with a good quality of life. Sorafenib can be provided on an outpatient basis and it may facilitate long-term survival for patients with advanced recurrent hepatocellular carcinoma with IVC tumor thrombus. This clinical condition is very rare, and the standard treatment for it still has not been established.

  20. [Survival after Sorafenib Treatment for Advanced Recurrent Hepatocellular Carcinoma with Tumor Thrombus in the Inferior Vena Cava].

    PubMed

    Matoba, Hideaki; Seta, Shinsuke

    2015-11-01

    A 72-year-old man with chronic viral hepatitis type B undergoing surgery for hepatocellular carcinoma was found to have a recurrent tumor in the left liver with peritoneal dissemination near the inferior vena cava(IVC)and tumor thrombus in the IVC. For this patient diagnosed with Barcelona clinic liver cancer (BCLC) classification stage C hepatocellular carcinoma, we initiated 800 mg/body sorafenib. Two weeks after the initiation of sorafenib, the patient experienced grade 3 hand-foot syndrome, after which, the dose of sorafenib was reduced to 400 mg/body. After 1 year, CT showed an enlarged tumor in the left liver and multiple metastases to the lung. However, no remarkable difference was observed in the peritoneal dissemination and the tumor thrombus. He has been receiving sorafenib for 19 months with a good quality of life. Sorafenib can be provided on an outpatient basis and it may facilitate long-term survival for patients with advanced recurrent hepatocellular carcinoma with IVC tumor thrombus. This clinical condition is very rare, and the standard treatment for it still has not been established. PMID:26805098

  1. Tree Size Inequality Reduces Forest Productivity: An Analysis Combining Inventory Data for Ten European Species and a Light Competition Model

    PubMed Central

    Bourdier, Thomas; Cordonnier, Thomas; Kunstler, Georges; Piedallu, Christian; Lagarrigues, Guillaume; Courbaud, Benoit

    2016-01-01

    Plant structural diversity is usually considered as beneficial for ecosystem functioning. For instance, numerous studies have reported positive species diversity-productivity relationships in plant communities. However, other aspects of structural diversity such as individual size inequality have been far less investigated. In forests, tree size inequality impacts directly tree growth and asymmetric competition, but consequences on forest productivity are still indeterminate. In addition, the effect of tree size inequality on productivity is likely to vary with species shade-tolerance, a key ecological characteristic controlling asymmetric competition and light resource acquisition. Using plot data from the French National Geographic Agency, we studied the response of stand productivity to size inequality for ten forest species differing in shade tolerance. We fitted a basal area stand production model that included abiotic factors, stand density, stand development stage and a tree size inequality index. Then, using a forest dynamics model we explored whether mechanisms of light interception and light use efficiency could explain the tree size inequality effect observed for three of the ten species studied. Size inequality negatively affected basal area increment for seven out of the ten species investigated. However, this effect was not related to the shade tolerance of these species. According to the model simulations, the negative tree size inequality effect could result both from reduced total stand light interception and reduced light use efficiency. Our results demonstrate that negative relationships between size inequality and productivity may be the rule in tree populations. The lack of effect of shade tolerance indicates compensatory mechanisms between effect on light availability and response to light availability. Such a pattern deserves further investigations for mixed forests where complementarity effects between species are involved. When studying the

  2. Continuous Modeling of Arterial Platelet Thrombus Formation Using a Spatial Adsorption Equation.

    PubMed

    Babushkina, Evgenia S; Bessonov, Nikolay M; Ataullakhanov, Fazoil I; Panteleev, Mikhail A

    2015-01-01

    In this study, we considered a continuous model of platelet thrombus growth in an arteriole. A special model describing the adhesion of platelets in terms of their concentration was derived. The applications of the derived model are not restricted to only describing arterial platelet thrombus formation; the model can also be applied to other similar adhesion processes. The model reproduces an auto-wave solution in the one-dimensional case; in the two-dimensional case, in which the surrounding flow is taken into account, the typical torch-like thrombus is reproduced. The thrombus shape and the growth velocity are determined by the model parameters. We demonstrate that the model captures the main properties of the thrombus growth behavior and provides us a better understanding of which mechanisms are important in the mechanical nature of the arterial thrombus growth.

  3. Asymptomatic large left-atrial ball thrombus. Secondary to mitral stenosis.

    PubMed Central

    Vitale, M; Agnino, A; Serena, D; Schena, S; Piscitelli, D; Fiore, T; de Luca Tupputi Schinosa, L

    1997-01-01

    We describe the very unusual case of a patient with a large, free-floating left-atrial thrombus secondary to severe mitral stenosis, in whom the peculiar symptoms and complications of a ball thrombus were absent. The patient's only symptom before the episode reported here was mild dyspnea, which was attributed to mitral stenosis. She experienced neither embolism nor syncope. While even her clinical signs did not indicate a left-atrial ball thrombus, both echocardiography and angiography showed a free-floating thrombus. Because of the risk of stroke and acute obstruction of the mitral valve, emergency surgery was performed upon diagnosis of the ball thrombus. The surgery, which consisted of removing the thrombus and replacing the mitral valve with a mechanical prosthesis, was uneventful. A computed tomographic brain scan prior to discharge did not detect any cerebral infarction. Images PMID:9456496

  4. Continuous Modeling of Arterial Platelet Thrombus Formation Using a Spatial Adsorption Equation.

    PubMed

    Babushkina, Evgenia S; Bessonov, Nikolay M; Ataullakhanov, Fazoil I; Panteleev, Mikhail A

    2015-01-01

    In this study, we considered a continuous model of platelet thrombus growth in an arteriole. A special model describing the adhesion of platelets in terms of their concentration was derived. The applications of the derived model are not restricted to only describing arterial platelet thrombus formation; the model can also be applied to other similar adhesion processes. The model reproduces an auto-wave solution in the one-dimensional case; in the two-dimensional case, in which the surrounding flow is taken into account, the typical torch-like thrombus is reproduced. The thrombus shape and the growth velocity are determined by the model parameters. We demonstrate that the model captures the main properties of the thrombus growth behavior and provides us a better understanding of which mechanisms are important in the mechanical nature of the arterial thrombus growth. PMID:26517377

  5. Reducing bias in rainfall estimates from microwave links by considering variable drop size distribution

    NASA Astrophysics Data System (ADS)

    Fencl, Martin; Jörg, Rieckermann; Vojtěch, Bareš

    2015-04-01

    Commercial microwave links (MWL) are point-to-point radio systems which are used in backhaul networks of cellular operators. For several years, they have been suggested as rainfall sensors complementary to rain gauges and weather radars, because, first, they operate at frequencies where rain drops represent significant source of attenuation and, second, cellular networks almost completely cover urban and rural areas. Usually, path-average rain rates along a MWL are retrieved from the rain-induced attenuation of received MWL signals with a simple model based on a power law relationship. The model is often parameterized based on the characteristics of a particular MWL, such as frequency, polarization and the drop size distribution (DSD) along the MWL. As information on the DSD is usually not available in operational conditions, the model parameters are usually considered constant. Unfortunately, this introduces bias into rainfall estimates from MWL. In this investigation, we propose a generic method to eliminate this bias in MWL rainfall estimates. Specifically, we search for attenuation statistics which makes it possible to classify rain events into distinct groups for which same power-law parameters can be used. The theoretical attenuation used in the analysis is calculated from DSD data using T-Matrix method. We test the validity of our approach on observations from a dedicated field experiment in Dübendorf (CH) with a 1.85-km long commercial dual-polarized microwave link transmitting at a frequency of 38 GHz, an autonomous network of 5 optical distrometers and 3 rain gauges distributed along the path of the MWL. The data is recorded at a high temporal resolution of up to 30s. It is further tested on data from an experimental catchment in Prague (CZ), where 14 MWLs, operating at 26, 32 and 38 GHz frequencies, and reference rainfall from three RGs is recorded every minute. Our results suggest that, for our purpose, rain events can be nicely characterized based on

  6. Reducing particle size of corn in lactation diets from 1,200 to 400 micrometers improves sow and litter performance.

    PubMed

    Wondra, K J; Hancock, J D; Kennedy, G A; Hines, R H; Behnke, K C

    1995-02-01

    One hundred primiparous sows were used to determine the effects of particle size of corn in lactation diets on sow and litter performance. The sows were fed a corn-soybean meal-based diet with the corn ground to 1,200, 900, 600, or 400 microns. Particle size of corn had no influence on sow BW or backfat loss (P > .30), subsequent weaning-to-estrus interval (P > .40), or percentage of sows returning to estrus (P > .09). However, ADFI was increased (linear effect, P < .04) as particle size was reduced from 1,200 to 400 microns. Pig survivability was not affected (P > .30) but litter BW gain was increased by 11% when sows were fed diets with 400 vs 1,200 microns corn (linear effect, P < .05). Apparent digestibilities of DM, N, and GE were increased by 5, 7, and 7%, respectively, as particle size was reduced from 1,200 to 400 microns (linear effects, P < .001). Intake of DE was increased 14% (13.7 to 15.6 Mcal/d) as corn particle size was reduced from 1,200 to 400 microns. Intakes of digestible DM and N also were increased (11 and 14%, respectively), whereas fecal excretions of DM and N were decreased by 21 and 31%, respectively (linear effects, P < .001). Reducing particle size increased severity of ulceration and keratinization (nonzero correlations of P < .04 and P < .004, respectively) in the esophageal region of the stomach, although the changes were not associated with reduced sow performance.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. An Informatics Based Approach to Reduce the Grain Size of Cast Hadfield Steel

    NASA Astrophysics Data System (ADS)

    Dey, Swati; Pathak, Shankha; Sheoran, Sumit; Kela, Damodar H.; Datta, Shubhabrata

    2016-04-01

    Materials Informatics concept using computational intelligence based approaches are employed to bring out the significant alloying additions to achieve grain refinement in cast Hadfield steel. Castings of Hadfield steels used for railway crossings, requires fine grained austenitic structure. Maintaining proper grain size of this component is very crucial in order to achieve the desired properties and service life. This work studies the important variables affecting the grain size of such steels which includes the compositional and processing variables. The computational findings and prior knowledge is used to design the alloy, which is subjected to a few trials to validate the findings.

  8. Reduced-size microchips for identification of horses: response to implantation and readability during a six-month period.

    PubMed

    Wulf, M; Aurich, C; von Lewinski, M; Möstl, E; Aurich, J E

    2013-11-01

    In this study, readability of reduced-size microchips in horses and the response to implantation were analysed. It was hypothesised that small microchips can be implanted stress-free but are less readable than larger microchips. Adult mares (n=40) were implanted with a reduced-size microchip (10.9×1.6 mm) at the left side of the neck (size of conventional microchips 11.4×2.2 mm). Microchips were identified with three different scanners (A, B, C) immediately, and at 6, 12 and 28 weeks after implantation. Twelve out of the 40 mares were submitted to microchip implantation and control treatments and cortisol, heart rate and heart rate variability (HRV) were determined. From the chip-bearing side of the neck, microchips were identified with all scanners in all horses at all times. From the contralateral side, correct readings were always 100 per cent with scanner C and with scanners A and B ranged between 60 and 100 per cent. Heart rate and HRV variable sd of beat-to-beat interval increased slightly (P<0.01) at microchip implantation and control treatment, but cortisol concentration did not increase. In conclusion, reduced-size microchips are highly reliable for identification of horses. Compared with conventional microchips, the reduction in size did not impair readability. Microchip implantation is no pronounced stressor for horses.

  9. Motor-Reducer Sizing through a MATLAB-Based Graphical Technique

    ERIC Educational Resources Information Center

    Giberti, H.; Cinquemani, S.

    2012-01-01

    The design of the drive system for an automatic machine and its correct sizing is a very important competence for an electrical or mechatronic engineer. This requires knowledge that crosses the fields of electrical engineering, electronics and mechanics, as well as the skill to choose commercial components based upon their technical documentation.…

  10. Size sorting of citrate reduced gold nanoparticles by sedimentation field-flow fractionation.

    PubMed

    Contado, Catia; Argazzi, Roberto

    2009-12-25

    Gold nanoparticles (GNPs) have been synthesized through the citrate reduction method; the citrate/gold(III) ratio was changed from 1:1 up to 10:1 and the size of the resulting nanoparticles was measured by sedimentation field-flow fractionation (SdFFF). Experimental data showed that the GNPs size decreases in the ratio range 1:1-3:1 and then increases from 5:1 to 10:1 passing through a plateau region in between, and is almost independent of the precursor solution concentrations. In the zone of minimum diameters the synthetic process does not produce monodispersed GNPs but often multiple distributions, very close in size, are observed as evidenced by the particle size distributions (PSDs) derived from the SdFFF fractograms. UV-vis spectrophotometry, being the most common technique employed in the optical characterization of nanoparticles suspensions, was used throughout this work. A confirmation of the nucleation-aggregation-fragmentation mechanism was inferred from the cross-correlation between UV-vis and SdFFF results.

  11. Winter grazing can reduce wildfire size, intensity, and behavior in a shrub-grassland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1. An increase in mega-fires and wildfires in general is a global issue that is expected to become worse with climate change. Fuel treatments are often recommended to decrease the risk, size, intensity, and severity of wildfires; however, the extensive nature of rangelands limits the use of many po...

  12. Community size and metabolic rates of psychrophilic sulfate-reducing bacteria in Arctic marine sediments

    SciTech Connect

    Knoblauch, C.; Joergensen, B.B.; Harder, J.

    1999-09-01

    The numbers of sulfate reducers in two Arctic sediments with in situ temperatures of 2.6 and {minus}1.7C were determined. Most-probable-number counts were higher at 10 C than at 20 C, indicating the predominance of a psychrophilic community. Mean specific sulfate reduction rates of 19 isolated psychrophiles were compared to corresponding rates of 9 marine, mesophilic sulfate-reducing bacteria. The results indicate that, as a physiological adaptation to the permanently cold Arctic environment, psychrophilic sulfate reducers have considerably higher specific metabolic rates than their mesophilic counterparts at similarly low temperatures.

  13. Estrogen alone or combined with medroxyprogesterone but not raloxifene reduce myocardial infarct size.

    PubMed

    Sbarouni, Eftihia; Iliodromitis, Efstathios K; Bofilis, Elias; Kyriakides, Zenon S; Kremastinos, Dimitrios Th

    2003-04-25

    We investigated whether estrogen protects the ischemic myocardium in oophorectomized female rabbits fed with a cholesterol-enriched diet, whether the addition of a progestin compound attenuates the beneficial effect of estrogen and whether raloxifene also limits myocardial necrosis. We treated 32 female oophorectomized hypercholesterolemic rabbits with (a) placebo (N=8, group I), (b) conjugated estrogens alone (N=8, group II), (c) conjugated estrogens combined continuously with medroxyprogesterone acetate (N=8, group III) and (d) raloxifene (N=8, group IV) all for 4 weeks. All rabbits underwent 30 min of ischemia and 120 min of reperfusion. Both infarct size (0.38+/-0.08 and 0.45+/-0.05 in groups II and III, respectively, vs. 0.78+/-0.07 in group I, P<0.005) and infarct size/risk zone% (26.34+/-4.18 and 35.01+/-4.39 in groups II and III, respectively, vs. 52.18+/-7.84 in group I, P<0.05) were significantly smaller in the estrogen treatment groups compared to placebo. No significant difference was observed between groups II and III. There was no significant difference between groups I and IV for infarct size (0.78+/-0.07 vs. 0.69+/-0.08, respectively) or for infarct size/risk zone% (52.18+/-7.84 vs. 47.17+/-4.3). Short-term estrogen protects ischemic myocardium in hypercholesterolemic oophorectomized female rabbits; this effect is not attenuated by the addition of a progestin compound. Raloxifene, however, does not decrease infarct size compared to placebo.

  14. Testing Probation Outcomes in an Evidence-Based Practice Setting: Reduced Caseload Size and Intensive Supervision Effectiveness

    ERIC Educational Resources Information Center

    Jalbert, Sarah Kuck; Rhodes, William; Flygare, Christopher; Kane, Michael

    2010-01-01

    Probation and parole professionals argue that supervision outcomes would improve if caseloads were reduced below commonly achieved standards. Criminal justice researchers are skeptical because random assignment and strong observation studies have failed to show that criminal recidivism falls with reductions in caseload sizes. One explanation is…

  15. BIOREACTOR ECONOMICS, SIZE AND TIME OF OPERATION (BEST) COMPUTER SIMULATOR FOR DESIGNING SULFATE-REDUCING BACTERIA FIELD BIOREACTORS

    EPA Science Inventory

    BEST (bioreactor economics, size and time of operation) is an Excel™ spreadsheet-based model that is used in conjunction with the public domain geochemical modeling software, PHREEQCI. The BEST model is used in the design process of sulfate-reducing bacteria (SRB) field bioreacto...

  16. The Cumulative Effects of Indiana PRIME TIME: A State Sponsored Reduced Class Size Program, on Basic Skills Achievement.

    ERIC Educational Resources Information Center

    Malloy, Leanne; Gilman, David

    The purpose of this paper was to analyze the initial results of statewide implementation of the PRIME TIME program in Indiana. PRIME TIME is a state-wide program to reduce class size in the primary grades. Mean scores from 65,911 third graders who had completed the Indiana Competency Test in the spring of 1987 after completing 3 years of the…

  17. Pathologic Features of Lone Aortic Mobile Thrombus in the Ascending Aorta.

    PubMed

    Endo, Hidehito; Ishii, Hikaru; Tsuchiya, Hiroshi; Takahashi, Yu; Shimoyamada, Hiroaki; Isomura, Aya; Nakajima, Masanori; Hirano, Teruyuki; Ohkura, Yasuo; Kubota, Hiroshi

    2016-10-01

    This report describes the case of a 79-year-old man with aortic mobile thrombus in the ascending aorta, followed by a discussion of the pathologic basis of aortic mobile thrombus formation. The patient underwent replacement of the ascending aorta. Macroscopic examination revealed an aortic wall ulcer with cholesterol-rich atherosclerotic plaque under the aortic mobile thrombus. Microscopic examination showed plaque rupture. These findings are very similar to those of plaque rupture in the coronary artery. We speculate that plaque rupture of localized aortic atherosclerosis is one of the causes of aortic mobile thrombus. PMID:27645970

  18. Ex vivo Time Evolution of Thrombus Growth through Optical and Electrical Impedance data fusion

    NASA Astrophysics Data System (ADS)

    Affanni, A.; Specogna, R.; Trevisan, F.

    2013-09-01

    We designed a novel sensor specifically aimed at ex vivo measurements of white thrombus volume growth; a white thrombus is induced within an artificial micro-channel where hemostasis takes place starting from whole blood under flow conditions. The advantage of the proposed methodology is to identify the time evolution of the thrombus volume by means of an original data fusion methodology based on 2D optical and electrical impedance data simultaneously processed. On the contrary, the present state of the art optical imaging methodologies allow the thrombus volume estimation only at the end of the hemostatic process.

  19. Derivatives of a statically reduced stiffness matrix with respect to sizing variables. [for aircraft weight minimization with flutter constraints

    NASA Technical Reports Server (NTRS)

    Oconnell, R. F.; Hassig, H. J.; Radovcich, N. A.

    1976-01-01

    An expression is obtained for the first derivatives with respect to the sizing variables of a statically reduced stiffness matrix that is a nonlinear function of the sizing variables, where the unreduced stiffness matrix is a linear function of the sizing variables. An accepted procedure to reduce the number of degrees of freedom is to eliminate a number of nodal displacements from the degrees of freedom such that the accuracy of the flutter analysis is not significantly affected. In a typical optimization procedure with flutter constraints, the derivative of the stiffness matrix may be used in a form that contains the characteristic vector of the flutter matrix equation and the transpose of the characteristic vector of the adjoint flutter matrix equation corresponding to a particular solution of the flutter equation.

  20. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species.

    PubMed

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-07-01

    The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960-2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. Lemmings have long been known to affect population productivity of Arctic-nesting migratory birds and, more

  1. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species

    PubMed Central

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-01-01

    1. The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). 2. Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. 3. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960–2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. 4. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. 5. Lemmings have long been known to affect population productivity of Arctic-nesting migratory

  2. Faltering lemming cycles reduce productivity and population size of a migratory Arctic goose species.

    PubMed

    Nolet, Bart A; Bauer, Silke; Feige, Nicole; Kokorev, Yakov I; Popov, Igor Yu; Ebbinge, Barwolt S

    2013-07-01

    The huge changes in population sizes of Arctic-nesting geese offer a great opportunity to study population limitation in migratory animals. In geese, population limitation seems to have shifted from wintering to summering grounds. There, in the Arctic, climate is rapidly changing, and this may impact reproductive performance, and perhaps population size of geese, both directly (e.g. by changes in snow melt) or indirectly (e.g. by changes in trophic interactions). Dark-bellied brent geese (Branta bernicla bernicla L.) increased 20-fold since the 1950s. Its reproduction fluctuates strongly in concert with the 3-year lemming cycle. An earlier analysis, covering the growth period until 1988, did not find evidence for density dependence, but thereafter the population levelled off and even decreased. The question is whether this is caused by changes in lemming cycles, population density or other factors like carry-over effects. Breeding success was derived from proportions of juveniles. We used an information-theoretical approach to investigate which environmental factors best explained the variation in breeding success over nearly 50 years (1960-2008). We subsequently combined GLM predictions of breeding success with published survival estimates to project the population trajectory since 1991 (year of maximum population size). In this way, we separated the effects of lemming abundance and population density on population development. Breeding success was mainly dependent on lemming abundance, the onset of spring at the breeding grounds, and the population size of brent goose. No evidence was found for carry-over effects (i.e. effects of conditions at main spring staging site). Negative density dependence was operating at a population size above c. 200 000 individuals, but the levelling off of the population could be explained by faltering lemming cycles alone. Lemmings have long been known to affect population productivity of Arctic-nesting migratory birds and, more

  3. Reducing the size of a data base by using pattern-recognition techniques

    SciTech Connect

    Clapp, N.E. Jr.

    1982-01-01

    An on-line surveillance system at a nuclear power plant samples data and calculates the power spectral density. A method of reducing the amount of stored data by screening the data using a pattern recognition technique was developed. The system stores only the spectra that differ from normal, plus the corresponding plant operating conditions. 7 figures.

  4. High-intensity training reduces intermittent hypoxia-induced ER stress and myocardial infarct size.

    PubMed

    Bourdier, Guillaume; Flore, Patrice; Sanchez, Hervé; Pepin, Jean-Louis; Belaidi, Elise; Arnaud, Claire

    2016-01-15

    Chronic intermittent hypoxia (IH) is described as the major detrimental factor leading to cardiovascular morbimortality in obstructive sleep apnea (OSA) patients. OSA patients exhibit increased infarct size after a myocardial event, and previous animal studies have shown that chronic IH could be the main mechanism. Endoplasmic reticulum (ER) stress plays a major role in the pathophysiology of cardiovascular disease. High-intensity training (HIT) exerts beneficial effects on the cardiovascular system. Thus, we hypothesized that HIT could prevent IH-induced ER stress and the increase in infarct size. Male Wistar rats were exposed to 21 days of IH (21-5% fraction of inspired O2, 60-s cycle, 8 h/day) or normoxia. After 1 wk of IH alone, rats were submitted daily to both IH and HIT (2 × 24 min, 15-30m/min). Rat hearts were either rapidly frozen to evaluate ER stress by Western blot analysis or submitted to an ischemia-reperfusion protocol ex vivo (30 min of global ischemia/120 min of reperfusion). IH induced cardiac proapoptotic ER stress, characterized by increased expression of glucose-regulated protein kinase 78, phosphorylated protein kinase-like ER kinase, activating transcription factor 4, and C/EBP homologous protein. IH-induced myocardial apoptosis was confirmed by increased expression of cleaved caspase-3. These IH-associated proapoptotic alterations were associated with a significant increase in infarct size (35.4 ± 3.2% vs. 22.7 ± 1.7% of ventricles in IH + sedenary and normoxia + sedentary groups, respectively, P < 0.05). HIT prevented both the IH-induced proapoptotic ER stress and increased myocardial infarct size (28.8 ± 3.9% and 21.0 ± 5.1% in IH + HIT and normoxia + HIT groups, respectively, P = 0.28). In conclusion, these findings suggest that HIT could represent a preventive strategy to limit IH-induced myocardial ischemia-reperfusion damages in OSA patients. PMID:26566725

  5. Analysis of reduced monoclonal antibodies using size exclusion chromatography coupled with mass spectrometry

    NASA Astrophysics Data System (ADS)

    Liu, Hongcheng; Gaza-Bulseco, Georgeen; Chumsae, Chris

    2009-12-01

    Size-exclusion chromatography (SEC) has been widely used to detect antibody aggregates, monomer, and fragments. SEC coupled to mass spectrometry has been reported to measure the molecular weights of antibody; antibody conjugates, and antibody light chain and heavy chain. In this study, separation of antibody light chain and heavy chain by SEC and direct coupling to a mass spectrometer was further studied. It was determined that employing mobile phases containing acetonitrile, trifluoroacetic acid, and formic acid allowed the separation of antibody light chain and heavy chain after reduction by SEC. In addition, this mobile phase allowed the coupling of SEC to a mass spectrometer to obtain a direct molecular weight measurement. The application of the SEC-MS method was demonstrated by the separation of the light chain and the heavy chain of multiple recombinant monoclonal antibodies. In addition, separation of a thioether linked light chain and heavy chain from the free light chain and the free heavy chain of a recombinant monoclonal antibody after reduction was also achieved. This optimized method provided a separation of antibody light chain and heavy chain based on size and allowed a direct measurement of molecular weights by mass spectrometry. In addition, this method may help to identify peaks eluting from SEC column directly.

  6. Significant enhancement of the thermoelectric figure of merit of polycrystalline Si films by reducing grain size

    NASA Astrophysics Data System (ADS)

    Valalaki, K.; Vouroutzis, N.; Nassiopoulou, A. G.

    2016-08-01

    The thermoelectric properties of p-type polycrystalline silicon thin films deposited by low pressure chemical vapour deposition (LPCVD) were accurately determined at room temperature and the thermoelectric figure of merit was deduced as a function of film thickness, ranging from 100 to 500 nm. The effect of film thickness on their thermoelectric performance is discussed. More than threefold increase in the thermoelectric figure of merit of the 100 nm thick polysilicon film was observed compared to the 500 nm thick film, reaching a value as high as 0.033. This enhancement is mainly the result of the smaller grain size in the thinner films. With the decrease in grain size the resistivity of the films is increased twofold and electrical conductivity decreased, however the Seebeck coefficient is increased by 30% and the thermal conductivity is decreased eightfold, being mainly at the origin of the increased figure of merit of the 100 nm film. Our experimental results were compared to known theoretical models and the possible mechanisms involved are presented and discussed.

  7. Salt stress reduces root meristem size by nitric oxide-mediated modulation of auxin accumulation and signaling in Arabidopsis.

    PubMed

    Liu, Wen; Li, Rong-Jun; Han, Tong-Tong; Cai, Wei; Fu, Zheng-Wei; Lu, Ying-Tang

    2015-05-01

    The development of the plant root system is highly plastic, which allows the plant to adapt to various environmental stresses. Salt stress inhibits root elongation by reducing the size of the root meristem. However, the mechanism underlying this process remains unclear. In this study, we explored whether and how auxin and nitric oxide (NO) are involved in salt-mediated inhibition of root meristem growth in Arabidopsis (Arabidopsis thaliana) using physiological, pharmacological, and genetic approaches. We found that salt stress significantly reduced root meristem size by down-regulating the expression of PINFORMED (PIN) genes, thereby reducing auxin levels. In addition, salt stress promoted AUXIN RESISTANT3 (AXR3)/INDOLE-3-ACETIC ACID17 (IAA17) stabilization, which repressed auxin signaling during this process. Furthermore, salt stress stimulated NO accumulation, whereas blocking NO production with the inhibitor N(ω)-nitro-l-arginine-methylester compromised the salt-mediated reduction of root meristem size, PIN down-regulation, and stabilization of AXR3/IAA17, indicating that NO is involved in salt-mediated inhibition of root meristem growth. Taken together, these findings suggest that salt stress inhibits root meristem growth by repressing PIN expression (thereby reducing auxin levels) and stabilizing IAA17 (thereby repressing auxin signaling) via increasing NO levels.

  8. Transient response in longitudinal grain size to reduced sediment supply in a large river

    NASA Astrophysics Data System (ADS)

    Singer, Michael

    2010-05-01

    Bed material grain size is an important degree of freedom in fluvial systems as they adjust to system-wide perturbations such as sediment supply changes. However, little is known about processes and patterns of such adjustment in longitudinal grain size sorting in large rivers. This research uses unprecedented datasets collected in a large fluvial system to investigate transient response to recent supply changes associated with anthropogenic activities. Separate fining trends for gravel and fines, a protracted gravel-sand (G-S) transition, and bed patchiness identified in Singer (2008) were interrogated using output from a hydraulic model with grain size distributions (GSDs) extracted from ~125 cross sections spanning ~400 river kilometers of the Sacramento River, California. The analysis suggests that interactions between hydraulics, bed material sorting, and sediment flux explain these previously identified anomalies. Highest values of sorting occur in the G-S transition and represent the overlap of separate fining trends for gravel and fines, where the long profile is jagged with evidence of progressive incision. Much of the sediment in this poorly sorted zone is organized into patches, where transport apparently occurs as bedload sheets. Patchiness occurs over short length scales leading to strong differences in entrainment and flux, regardless of hydraulic conditions. A modified Shields stress is proposed that is scaled by GSD sorting to improve characterization of entrainment/disentrainment. Sediment flux calculations based on an equation sensitive bed material conditions (Singer and Dunne, 2004) reveal a strong relationship between fine sediment flux and d90, suggesting that the efficiency of fine patch flux controls bed material bed surface roughness. Results are in part consistent with Paola and Seal (1995) suggesting that patches are a result of overlapping pdfs of shear stress and sorting and with Ferguson (2003) in that the final end of the protracted G

  9. Fibrinolytic treatment of thrombus on prosthetic heart valves.

    PubMed Central

    Witchitz, S; Veyrat, C; Moisson, P; Scheinman, N; Rozenstajn, L

    1980-01-01

    Fibrinolytic agents were administered for 13 episodes of thrombus formation on mitral or aortic valvar prostheses in 12 patients. The most common presenting features were pulmonary oedema (six cases) or arterial emboli (six cases). The diagnosis of thrombus formation was made by phonocardiography on the following criteria: (a) modifications of the prosthetic sounds (12 cases), (b) appearance of a valvar obstructive syndrome (10 cases). The treatment consisted of streptokinase (100 000 units/h after a loading dose, seven cases) or urokinase using either low doses (75 000 or 112 500 units/h, three cases) or moderate doses (150 000 units/h, three cases) for one to four days. Immediate complete regression of clinical and phonocardiographic anomalies was seen in eight cases. Incomplete improvement was seen in two patients, leading to operation: this was unsuccessful in one patient who had surgery on the third day, and was successful in the other on the 75th day. There were three failures leading to successful reoperative procedures in two patients and to an early death in the third patient suffering from acute myocardial infarction. One non-fatal haemopericardium was observed in a patient treated with streptokinase. No important side effect was noted during delivery in a pregnant woman. During subsequent follow-up, a recurrent episode of thrombus formation was observed in one patient, treated by fibrinolytic therapy with success. One patient had an operation for a valve replacement six months after fibrinolytic treatment because of non-thrombotic valvar dysfunction; the outcome was fatal. Six patients are alive and in good condition, with a follow-up of six months to five years. Images PMID:7437196

  10. Role of Gas6 receptors in platelet signaling during thrombus stabilization and implications for antithrombotic therapy

    PubMed Central

    Angelillo-Scherrer, Anne; Burnier, Laurent; Flores, Nathalie; Savi, Pierre; DeMol, Maria; Schaeffer, Paul; Herbert, Jean-Marc; Lemke, Greg; Goff, Stephen P.; Matsushima, Glenn K.; Earp, H. Shelton; Vesin, Christian; Hoylaerts, Marc F.; Plaisance, Stéphane; Collen, Désiré; Conway, Edward M.; Wehrle-Haller, Bernhard; Carmeliet, Peter

    2005-01-01

    Mechanisms regulating thrombus stabilization remain largely unknown. Here, we report that loss of any 1 of the Gas6 receptors (Gas6-Rs), i.e., Tyro3, Axl, or Mer, or delivery of a soluble extracellular domain of Axl that traps Gas6 protects mice against life-threatening thrombosis. Loss of a Gas6-R does not prevent initial platelet aggregation but impairs subsequent stabilization of platelet aggregates, at least in part by reducing “outside-in” signaling and platelet granule secretion. Gas6, through its receptors, activates PI3K and Akt and stimulates tyrosine phosphorylation of the β3 integrin, thereby amplifying outside-in signaling via αIIbβ3. Blocking the Gas6-R–αIIbβ3 integrin cross-talk might be a novel approach to the reduction of thrombosis. PMID:15650770

  11. What keeps insects small? Time limitation during oviposition reduces the fecundity benefit of female size in a butterfly.

    PubMed

    Gotthard, Karl; Berger, David; Walters, Richard

    2007-06-01

    Laboratory studies of insects suggest that female fecundity may increase very rapidly with adult size and that mass may often increase close to exponentially with time during larval growth. These relationships make it difficult to see how realistic levels of larval mortality can outweigh the fecundity benefit of prolonged growth. Hence, it is unclear why many insects do not become bigger. In this study, we experimentally explore the relationship between female size and fecundity in the butterfly Pararge aegeria and show that thermally induced time limitation during oviposition may substantially reduce the fecundity benefit of larger females. We model time-limited oviposition under natural temperature conditions and show that fecundity is also likely to increase asymptotically with female size in the field. With realistic estimates of juvenile mortality, the model predicts optimal body sizes within the observed range even when larvae grow exponentially. We conclude that one important reason for why insects with a high capacity of larval growth do not evolve toward larger sizes may be that the fecundity benefit is in fact relatively limited under natural conditions. If so, these results may help resolve some of the inconsistencies between theory and empirical patterns in explaining optimal size in insects.

  12. Left ventricular thrombus: an unusual cause of stroke.

    PubMed

    Youngster, Ilan; Eshel, Gideon; Abu-kishak, Ibrahim; Heyman, Eli; Baram, Shaul

    2007-11-01

    An 8-year-old boy was admitted to the hospital with multiple abdominal and pelvic injuries following a motor vehicle accident. During hospitalization, signs of stroke developed. Evaluation discovered the cause to be emboli originating from a large left ventricular thrombus, most probably as a result of cardiac injury. Anticoagulation therapy was initiated, the cardiac mass resolved completely within 3 days, and neurologic status subsequently improved. When possible, echocardiography should be used as part of the workup of pediatric patients after multiple trauma, even without obvious signs of chest involvement.

  13. Aortoiliac thrombus secondary to a mineralized arteriosclerotic lesion.

    PubMed

    Drost, W T; Bahr, R J; Henry, G A; Campbell, G A

    1999-01-01

    A 12-year-old, neutered female, Siberian Husky dog presented with a hind limb weakness of one month duration. To facilitate making a diagnosis multiple imaging modalities were performed. These modalities included radiography, ultrasonography, magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and selective angiography of the abdominal aorta. In this dog, the MRI/MRA studies provided the first documentation of the external iliac thrombi and the collateral circulation via the lumbar arteries. At necropsy, an aortoiliac thrombus caused by a mineralized arteriosclerotic plaque was noted.

  14. Reducing Size, Weight, and Power (SWaP) of Perception Systems in Small Autonomous Aerial Systems

    NASA Technical Reports Server (NTRS)

    Jones, Kennie H.; Gross, Jason

    2014-01-01

    The objectives are to examine recent trends in the reduction of size, weight, and power (SWaP) requirements of sensor systems for environmental perception and to explore new technology that may overcome limitations in current systems. Improving perception systems to facilitate situation awareness is critical in the move to introduce increasing autonomy in aerial systems. Whether the autonomy is in the current state-of-the-art of increasing automation or is enabling cognitive decisions that facilitate adaptive behavior, collection of environmental information and fusion of that information into knowledge that can direct actuation is imperative to decisions resulting in appropriate behavior. Artificial sensory systems such as cameras, radar, LIDAR, and acoustic sensors have been in use on aircraft for many years but, due to the large size and weight of the airplane and electrical power made available through powerful engines, the SWaP requirements of these sensors was inconsequential. With the proliferation of Remote Piloted Vehicles (RPV), the trend is in significant reduction in SWaP of the vehicles. This requires at least an equivalent reduction in SWaP for the sensory systems. A survey of some currently available sensor systems and changing technology will reveal the trend toward reduction of SWaP of these systems and will predict future reductions. A new technology will be introduced that provides an example of a desirable new trend. A new device replaces multiple conventional sensory devices facilitating synchronization, localization, altimetry, collision avoidance, terrain mapping, and data communication in a single integrated, small form-factor, extremely lightweight, and low power device that it is practical for integration into small autonomous vehicles and can facilitate cooperative behavior. The technology is based on Ultra WideBand (UWB) radio using short pulses of energy rather than continuous sine waves. The characteristics of UWB yield several

  15. Laser system refinements to reduce variability in infarct size in the rat photothrombotic stroke model

    PubMed Central

    Alaverdashvili, Mariam; Paterson, Phyllis G.; Bradley, Michael P.

    2015-01-01

    Background The rat photothrombotic stroke model can induce brain infarcts with reasonable biological variability. Nevertheless, we observed unexplained high inter-individual variability despite using a rigorous protocol. Of the three major determinants of infarct volume, photosensitive dye concentration and illumination period were strictly controlled, whereas undetected fluctuation in laser power output was suspected to account for the variability. New method The frequently utilized Diode Pumped Solid State (DPSS) lasers emitting 532 nm (green) light can exhibit fluctuations in output power due to temperature and input power alterations. The polarization properties of the Nd:YAG and Nd:YVO4 crystals commonly used in these lasers are another potential source of fluctuation, since one means of controlling output power uses a polarizer with a variable transmission axis. Thus, the properties of DPSS lasers and the relationship between power output and infarct size were explored. Results DPSS laser beam intensity showed considerable variation. Either a polarizer or a variable neutral density filter allowed adjustment of a polarized laser beam to the desired intensity. When the beam was unpolarized, the experimenter was restricted to using a variable neutral density filter. Comparison with existing method(s) Our refined approach includes continuous monitoring of DPSS laser intensity via beam sampling using a pellicle beamsplitter and photodiode sensor. This guarantees the desired beam intensity at the targeted brain area during stroke induction, with the intensity controlled either through a polarizer or variable neutral density filter. Conclusions Continuous monitoring and control of laser beam intensity is critical for ensuring consistent infarct size. PMID:25840363

  16. Comparing fuel reduction treatments for reducing wildfire size and intensity in a boreal forest landscape of northeastern China.

    PubMed

    Wu, Zhiwei; He, Hong S; Liu, Zhihua; Liang, Yu

    2013-06-01

    Fuel load is often used to prioritize stands for fuel reduction treatments. However, wildfire size and intensity are not only related to fuel loads but also to a wide range of other spatially related factors such as topography, weather and human activity. In prioritizing fuel reduction treatments, we propose using burn probability to account for the effects of spatially related factors that can affect wildfire size and intensity. Our burn probability incorporated fuel load, ignition probability, and spread probability (spatial controls to wildfire) at a particular location across a landscape. Our goal was to assess differences in reducing wildfire size and intensity using fuel-load and burn-probability based treatment prioritization approaches. Our study was conducted in a boreal forest in northeastern China. We derived a fuel load map from a stand map and a burn probability map based on historical fire records and potential wildfire spread pattern. The burn probability map was validated using historical records of burned patches. We then simulated 100 ignitions and six fuel reduction treatments to compare fire size and intensity under two approaches of fuel treatment prioritization. We calibrated and validated simulated wildfires against historical wildfire data. Our results showed that fuel reduction treatments based on burn probability were more effective at reducing simulated wildfire size, mean and maximum rate of spread, and mean fire intensity, but less effective at reducing maximum fire intensity across the burned landscape than treatments based on fuel load. Thus, contributions from both fuels and spatially related factors should be considered for each fuel reduction treatment.

  17. Tumour thrombus consistency has no impact on survival in patients with renal cell carcinoma.

    PubMed

    Gołąbek, T; Przydacz, M; Okoń, K; Kopczyński, J; Bukowczan, J; Sobczyński, R; Curyło, Ł; Gołąbek, K; Curyło, Ł; Chłosta, P

    2016-06-01

    The prognosis of renal cell carcinoma (RCC) with venous tumour thrombus (VTT) is variable and not always possible to predict. The prognostic impact and independence of tumour thrombus-related factors including the recently introduced tumour thrombus consistency (TTC) on overall survival remain controversial. The aim of this study was to investigate the prognostic role of TTC in patients' survival. We determined the tumour thrombus consistency (solid vs. friable) in a cohort of 84 patients with RCC and VTT who underwent nephrectomy with thrombectomy, and performed a retrospective evaluation of the patients' data from the prospectively maintained database. A total of 45% of patients had solid thrombus (sTT) and 55% had friable thrombus (fTT). The venous tumour thrombus consistency was not predictive of overall survival. Further studies, preferably prospective and with a larger number of patients, are needed to validate the obtained results, as well as to evaluate the usefulness of tumour thrombus consistency in clinical practice for stratifying the risk of recurrence and planning further follow-up. PMID:27543869

  18. Dual antiplatelet agents and Rivaroxaban for massive intracoronary thrombus in STEMI

    PubMed Central

    Jamal, Nasiruddin; Bapumia, Mustaafa

    2015-01-01

    Key Clinical Message Management of intracoronary thrombus in patients presenting more than 12 hours after the onset of ST elevation myocardial infarction is challenging. We present such a case which had massive thrombus in left anterior descending artery. It was managed successfully with dual antiplatelet agents and factor Xa inhibitor rivaroxaban administered orally. PMID:26576274

  19. AngioVac extraction of intra-atrial hepatoma masquerading as PICC-associated thrombus.

    PubMed

    Abboud, Samir; Raparia, Kirtee; Ubago, Julianne M; Resnick, Scott

    2016-01-01

    Thrombus associated with peripherally inserted central catheterization is not uncommon. Treatment is typically conservative; however, more aggressive therapies can be considered in patients with tenuous medical condition. The authors present a patient with metastatic hepatocellular carcinoma masquerading as peripherally inserted central catheter-associated intra-atrial thrombus, subsequently removed via vacuum-assisted mechanical thrombectomy.

  20. AngioVac extraction of intra-atrial hepatoma masquerading as PICC-associated thrombus

    PubMed Central

    Abboud, Samir; Raparia, Kirtee; Ubago, Julianne M.; Resnick, Scott

    2016-01-01

    Thrombus associated with peripherally inserted central catheterization is not uncommon. Treatment is typically conservative; however, more aggressive therapies can be considered in patients with tenuous medical condition. The authors present a patient with metastatic hepatocellular carcinoma masquerading as peripherally inserted central catheter-associated intra-atrial thrombus, subsequently removed via vacuum-assisted mechanical thrombectomy. PMID:26509915

  1. Tumour thrombus consistency has no impact on survival in patients with renal cell carcinoma.

    PubMed

    Gołąbek, T; Przydacz, M; Okoń, K; Kopczyński, J; Bukowczan, J; Sobczyński, R; Curyło, Ł; Gołąbek, K; Curyło, Ł; Chłosta, P

    2016-06-01

    The prognosis of renal cell carcinoma (RCC) with venous tumour thrombus (VTT) is variable and not always possible to predict. The prognostic impact and independence of tumour thrombus-related factors including the recently introduced tumour thrombus consistency (TTC) on overall survival remain controversial. The aim of this study was to investigate the prognostic role of TTC in patients' survival. We determined the tumour thrombus consistency (solid vs. friable) in a cohort of 84 patients with RCC and VTT who underwent nephrectomy with thrombectomy, and performed a retrospective evaluation of the patients' data from the prospectively maintained database. A total of 45% of patients had solid thrombus (sTT) and 55% had friable thrombus (fTT). The venous tumour thrombus consistency was not predictive of overall survival. Further studies, preferably prospective and with a larger number of patients, are needed to validate the obtained results, as well as to evaluate the usefulness of tumour thrombus consistency in clinical practice for stratifying the risk of recurrence and planning further follow-up.

  2. Dual antiplatelet agents and Rivaroxaban for massive intracoronary thrombus in STEMI.

    PubMed

    Jamal, Nasiruddin; Bapumia, Mustaafa

    2015-11-01

    Management of intracoronary thrombus in patients presenting more than 12 hours after the onset of ST elevation myocardial infarction is challenging. We present such a case which had massive thrombus in left anterior descending artery. It was managed successfully with dual antiplatelet agents and factor Xa inhibitor rivaroxaban administered orally. PMID:26576274

  3. Awns reduce grain number to increase grain size and harvestable yield in irrigated and rainfed spring wheat

    PubMed Central

    Rebetzke, G. J.; Bonnett, D. G.; Reynolds, M. P.

    2016-01-01

    Genotypic variation in ear morphology is linked to differences in photosynthetic potential to influence grain yield in winter cereals. Awns contribute to photosynthesis, particularly under water-limited conditions when canopy assimilation is restricted. We assessed performance of up to 45 backcross-derived, awned–awnletted NILs representing four diverse genetic backgrounds in 25 irrigated or rainfed, and droughted environments in Australia and Mexico. Mean environment grain yields were wide-ranging (1.38–7.93 t ha−1) with vegetative and maturity biomass, plant height, anthesis date, spike number, and harvest index all similar (P >0.05) for awned and awnletted NILs. Overall, grain yields of awned–awnletted sister-NILs were equivalent, irrespective of yield potential and genetic background. Awnletted wheats produced significantly more grains per unit area (+4%) and per spike (+5%) reflecting more fertile spikelets and grains in tertiary florets. Increases in grain number were compensated for by significant reductions in grain size (–5%) and increased frequency (+0.8%) of small, shrivelled grains (‘screenings’) to reduce seed-lot quality of awnletted NILs. Post-anthesis canopies of awnletted NILs were marginally warmer over all environments (+0.27 °C) but were not different and were sometimes cooler than awned NILs at cooler air temperatures. Awns develop early and represented up to 40% of total spikelet biomass prior to ear emergence. We hypothesize that the allocation of assimilate to large and rapidly developing awns decreases spikelet number and floret fertility to reduce grain number, particularly in distal florets. Individual grain size is increased to reduce screenings and to increase test weight and milling quality, particularly in droughted environments. Despite the average reduction in grain size, awnless lines could be identified that combined higher grain yield with larger grain size, increased grain protein concentration, and reduced

  4. Arginase inhibition improves coronary microvascular function and reduces infarct size following ischemia-reperfusion in a rat model

    PubMed Central

    Grönros, Julia; Kiss, Attila; Palmér, Malin; Jung, Christian; Berkowitz, Dan; Pernow, John

    2013-01-01

    Aim Ischemia-reperfusion injury is associated with reduced bioavailability of nitric oxide and microvascular dysfunction. One emerging mechanism behind reduced nitric oxide bioavailability is upregulation of arginase which metabolizes the nitric oxide synthase substrate L-arginine. This study investigated the effects of arginase inhibition on coronary flow velocity and infarct size during reperfusion. Methods Anaesthetized rats, subjected to 30 min coronary artery ligation and reperfusion up to 8 days, were treated with vehicle or the arginase inhibitor Nω-hydroxy-nor-L-arginine (nor-NOHA; 100 mg/kg) intravenously 15 min before ischemia. Coronary flow velocity was determined repeatedly during reperfusion. Results Arginase activity in the ischemic-reperfused myocardium was increased already at 20 min of reperfusion and maintained at 8 days. Infarct size was reduced by arginase inhibition at 2 h (39 ± 3% of the area at risk vs. 51 ± 2% in the vehicle group, P<0.01) and at 8 days of reperfusion (13 ± 2% of the left ventricle vs. 22 ± 2%, P<0.05). Basal coronary flow velocity was higher during reperfusion in the group given nor-NOHA and it correlated inversely to infarct size (P<0.01, r=−0.60). Hyperemic coronary flow velocity was also increased in the nor-NOHA treated group compared to vehicle at 24 h and at day 8 (P<0.05). Conclusion It is concluded that arginase activity is increased already during early reperfusion. Arginase inhibition increases coronary flow velocity and reduces infarct size that is sustained 8 days after reperfusion. Inhibition of arginase may thus be a promising therapeutic target to prevent the development of microvascular dysfunction and myocardial injury following ischemia-reperfusion. PMID:23497275

  5. Effect of homogenization techniques on reducing the size of microcapsules and the survival of probiotic bacteria therein.

    PubMed

    Ding, W K; Shah, N P

    2009-08-01

    This study investigated 2 different homogenization techniques for reducing the size of calcium alginate beads during the microencapsulation process of 8 probiotic bacteria strains, namely, Lactobacillus rhamnosus, L. salivarius, L. plantarum, L. acidophilus, L. paracasei, Bifidobacterium longum, B. lactis type Bi-04, and B. lactis type Bi-07. Two different homogenization techniques were used, namely, ultra-turrax benchtop homogenizer and Microfluidics microfluidizer. Various settings on the homogenization equipment were studied such as the number of passes, speed (rpm), duration (min), and pressure (psi). The traditional mixing method using a magnetic stirrer was used as a control. The size of microcapsules resulting from the homogenization technique, and the various settings were measured using a light microscope and a stage micrometer. The smallest capsules measuring (31.2 microm) were created with the microfluidizer using 26 passes at 1200 psi for 40 min. The greatest loss in viability of 3.21 log CFU/mL was observed when using the ultra-turrax benchtop homogenizer with a speed of 1300 rpm for 5 min. Overall, both homogenization techniques reduced capsule sizes; however, homogenization settings at high rpm also greatly reduced the viability of probiotic organisms.

  6. A reduced estimate of the number of kilometre-sized near-Earth asteroids.

    PubMed

    Rabinowitz, D; Helin, E; Lawrence, K; Pravdo, S

    2000-01-13

    Near-Earth asteroids are small (diameters < 10 km), rocky bodies with orbits that approach that of the Earth (they come within 1.3 AU of the Sun). Most have a chance of approximately 0.5% of colliding with the Earth in the next million years. The total number of such bodies with diameters > 1 km has been estimated to be in the range 1,000-2,000, which translates to an approximately 1% chance of a catastrophic collision with the Earth in the next millennium. These numbers are, however, poorly constrained because of the limitations of previous searches using photographic plates. (One kilometre is below the size of a body whose impact on the Earth would produce global effects.) Here we report an analysis of our survey for near-Earth asteroids that uses improved detection technologies. We find that the total number of asteroids with diameters > 1 km is about half the earlier estimates. At the current rate of discovery of near-Earth asteroids, 90% will probably have been detected within the next 20 years.

  7. CV205-502, a new non-ergot dopamine agonist, reduces prolactinoma size in man.

    PubMed

    Barnett, P S; Dawson, J M; Butler, J; Coskeran, P B; Maccabe, J J; McGregor, A M

    1990-08-01

    Seven patients with large prolactin-secreting pituitary adenomas were treated for 8 weeks with once-daily doses of the new, potent, non-ergot, long-acting dopamine agonist CV205-502. In five patients previous treatment with bromocriptine had failed to control their disease or been poorly tolerated and had therefore ceased. In all seven patients serum prolactin levels fell over the 8-week period of CV205-502 treatment with the decrease ranging from 33 to 99%. Associated with this decline in prolactin all patients showed symptomatic improvement with two of the five women beginning to menstruate and the two patients with visual field impairment showing marked improvement. Tolerance of the drug, with doses at 8 weeks ranging from 0.075 to 0.3 mg, was excellent with only minimal and transient side-effects being noted in three patients in none of whom was discontinuation of therapy necessary. In one patient noncompliance after 6 weeks of therapy was associated with a rapid return of her serum prolactin towards pretreatment levels. In all seven patients the clinical and biochemical improvement was accompanied by a marked reduction in tumour size.

  8. Reducing the size of the human physiological blind spot through training.

    PubMed

    Miller, Paul A; Wallis, Guy; Bex, Peter J; Arnold, Derek H

    2015-08-31

    The physiological blind spot refers to a zone of functional blindness all normally sighted people have in each eye, due to an absence of photoreceptors where the optic nerve passes through the surface of the retina. Here we report that the functional size of the physiological blind spot can be shrunk through training to distinguish direction signals at the blind spot periphery. Training on twenty successive weekdays improved sensitivity to both direction and colour, suggesting a generalizable benefit. Training on one blind spot, however, did not transfer to the blind spot in the untrained eye, ruling out mediation via a generic practice effect; nor could training benefits be attributed to eye movements, which were monitored to ensure stable fixation. These data suggest that training enhances the response gains of neurons with receptive fields that partially overlap, or abut, the physiological blind spot, thereby enhancing sensitivity to weak signals originating primarily from within the functionally-defined region of blindness [1-3]. Our results have important implications for situations where localised blindness has been acquired through damage to components of the visual system [4,5], and support proposals that these situations might be improved through perceptual training [5-7]. PMID:26325131

  9. Reduced molecular size and altered disaccharide composition of cerebral chondroitin sulfate upon Alzheimer's pathogenesis in mice.

    PubMed

    Zhang, Zui; Ohtake-Niimi, Shiori; Kadomatsu, Kenji; Uchimura, Kenji

    2016-08-01

    Alzheimer's disease (AD) is a progressive disorder leading to cognitive impairment and neuronal loss. Cerebral extracellular accumulation and deposition of amyloid ß plaques is a pathological hallmark of AD. Chondroitin sulfate (CS) is an extracellular component abundant in the brain. CS is a sulfated glycosaminoglycan covalently attached to a core protein, forming chondroitin sulfate proteoglycan. The structure of CS is heterogeneous with sulfation modification and elongation of the chain. The structural diversity of CS allows it to play various roles in the brain. Increasing evidence has shown that CS promotes aggregation of amyloid ß peptides into higher-order species such as insoluble amyloid ß fibrils. Difficulties in the structural analysis of brain CS, as well as its heterogeneity, limit the study of potential roles of CS in AD pathology. Here we established a microanalysis method with reversed-phase ion-pair high performance liquid chromatography and found that CS in the brains of Tg2576 AD model mice show a lower molecular size and an increased ratio of CS-B motif di-sulfated disaccharide. Our findings provide insight into the structural changes of cerebral CS upon Alzheimer's pathogenesis. PMID:27578913

  10. Reducing the size of the human physiological blind spot through training.

    PubMed

    Miller, Paul A; Wallis, Guy; Bex, Peter J; Arnold, Derek H

    2015-08-31

    The physiological blind spot refers to a zone of functional blindness all normally sighted people have in each eye, due to an absence of photoreceptors where the optic nerve passes through the surface of the retina. Here we report that the functional size of the physiological blind spot can be shrunk through training to distinguish direction signals at the blind spot periphery. Training on twenty successive weekdays improved sensitivity to both direction and colour, suggesting a generalizable benefit. Training on one blind spot, however, did not transfer to the blind spot in the untrained eye, ruling out mediation via a generic practice effect; nor could training benefits be attributed to eye movements, which were monitored to ensure stable fixation. These data suggest that training enhances the response gains of neurons with receptive fields that partially overlap, or abut, the physiological blind spot, thereby enhancing sensitivity to weak signals originating primarily from within the functionally-defined region of blindness [1-3]. Our results have important implications for situations where localised blindness has been acquired through damage to components of the visual system [4,5], and support proposals that these situations might be improved through perceptual training [5-7].

  11. Effective size of a wild salmonid population is greatly reduced by hatchery supplementation.

    PubMed

    Christie, M R; Marine, M L; French, R A; Waples, R S; Blouin, M S

    2012-10-01

    Many declining and commercially important populations are supplemented with captive-born individuals that are intentionally released into the wild. These supplementation programs often create large numbers of offspring from relatively few breeding adults, which can have substantial population-level effects. We examined the genetic effects of supplementation on a wild population of steelhead (Oncorhynchus mykiss) from the Hood River, Oregon, by matching 12 run-years of hatchery steelhead back to their broodstock parents. We show that the effective number of breeders producing the hatchery fish (broodstock parents; N(b)) was quite small (harmonic mean N(b)=25 fish per brood-year vs 373 for wild fish), and was exacerbated by a high variance in broodstock reproductive success among individuals within years. The low N(b) caused hatchery fish to have decreased allelic richness, increased average relatedness, more loci in linkage disequilibrium and substantial levels of genetic drift in comparison with their wild-born counterparts. We also documented a substantial Ryman-Laikre effect whereby the additional hatchery fish doubled the total number of adult fish on the spawning grounds each year, but cut the effective population size of the total population (wild and hatchery fish combined) by nearly two-thirds. We further demonstrate that the Ryman-Laikre effect is most severe in this population when (1) >10% of fish allowed onto spawning grounds are from hatcheries and (2) the hatchery fish have high reproductive success in the wild. These results emphasize the trade-offs that arise when supplementation programs attempt to balance disparate goals (increasing production while maintaining genetic diversity and fitness).

  12. Antiadhesive effect of fibrinogen: a safeguard for thrombus stability

    PubMed Central

    Lishko, Valeryi K.; Burke, Timothy; Ugarova, Tatiana

    2007-01-01

    The recruitment of phagocytic leukocytes to sites of vessel wall injury plays an important role in thrombus dissolution by proteases elaborated on their adhesion. However, leukocyte adhesion to the fibrin clot can be detrimental at the early stages of wound healing when hemostatic plug integrity is critical for preventing blood loss. Adhesion of circulating leukocytes to the insoluble fibrin(ogen) matrix is mediated by integrins and occurs in the presence of a high concentration of plasma fibrinogen. In this study, the possibility that soluble fibrinogen could protect fibrin from excessive adhesion of leukocytes was examined. Fibrinogen was a potent inhibitor of adhesion of U937 monocytoid cells and neutrophils to fibrin gel and immobilized fibrin(ogen). An investigation of the mechanism by which soluble fibrinogen exerts its influence on leukocyte adhesion indicated that it did not block integrins but rather associated with the fibrin(ogen) substrate. Consequently, leukocytes that engage fibrinogen molecules loosely bound to the surface of fibrin(ogen) matrix are not able to consolidate their grip on the substrate; subsequently, cells detach. This conclusion is based on the evidence obtained in adhesion studies using various cells and performed under static and flow conditions. These findings reveal a new role of fibrinogen in integrin-mediated leukocyte adhesion and suggest that this mechanism may protect the thrombus from premature dissolution. PMID:16849640

  13. Improved molecular imaging contrast agent for detection of human thrombus.

    PubMed

    Winter, Patrick M; Caruthers, Shelton D; Yu, Xin; Song, Sheng-Kwei; Chen, Junjie; Miller, Brad; Bulte, Jeff W M; Robertson, J David; Gaffney, Patrick J; Wickline, Samuel A; Lanza, Gregory M

    2003-08-01

    Molecular imaging of microthrombus within fissures of unstable atherosclerotic plaques requires sensitive detection with a thrombus-specific agent. Effective molecular imaging has been previously demonstrated with fibrin-targeted Gd-DTPA-bis-oleate (BOA) nanoparticles. In this study, the relaxivity of an improved fibrin-targeted paramagnetic formulation, Gd-DTPA-phosphatidylethanolamine (PE), was compared with Gd-DTPA-BOA at 0.05-4.7 T. Ion- and particle-based r(1) relaxivities (1.5 T) for Gd-DTPA-PE (33.7 (s*mM)(-1) and 2.48 x 10(6) (s*mM)(-1), respectively) were about twofold higher than for Gd-DTPA-BOA, perhaps due to faster water exchange with surface gadolinium. Gd-DTPA-PE nanoparticles bound to thrombus surfaces via anti-fibrin antibodies (1H10) induced 72% +/- 5% higher change in R(1) values at 1.5 T (deltaR(1) = 0.77 +/- 0.02 1/s) relative to Gd-DTPA-BOA (deltaR(1) = 0.45 +/- 0.02 1/s). These studies demonstrate marked improvement in a fibrin-specific molecular imaging agent that might allow sensitive, early detection of vascular microthrombi, the antecedent to stroke and heart attack.

  14. Platelet adhesion signalling and the regulation of thrombus formation.

    PubMed

    Gibbins, Jonathan M

    2004-07-15

    Platelets perform a central role in haemostasis and thrombosis. They adhere to subendothelial collagens exposed at sites of blood vessel injury via the glycoprotein (GP) Ib-V-IX receptor complex, GPVI and integrin alpha(2)beta(1). These receptors perform distinct functions in the regulation of cell signalling involving non-receptor tyrosine kinases (e.g. Src, Fyn, Lyn, Syk and Btk), adaptor proteins, phospholipase C and lipid kinases such as phosphoinositide 3-kinase. They are also coupled to an increase in cytosolic calcium levels and protein kinase C activation, leading to the secretion of paracrine/autocrine platelet factors and an increase in integrin receptor affinities. Through the binding of plasma fibrinogen and von Willebrand Factor to integrin alpha(IIb)beta(3), a platelet thrombus is formed. Although increasing evidence indicates that each of the adhesion receptors GPIb-V-IX and GPVI and integrins alpha(2)beta(1) and alpha(IIb)beta(3) contribute to the signalling that regulates this process, the individual roles of each are only beginning to be dissected. By contrast, adhesion receptor signalling through platelet endothelial cell adhesion molecule 1 (PECAM-1) is implicated in the inhibition of platelet function and thrombus formation in the healthy circulation. Recent studies indicate that understanding of platelet adhesion signalling mechanisms might enable the development of new strategies to treat and prevent thrombosis. PMID:15252124

  15. Total Mechanical Unloading Minimizes Metabolic Demand of Left Ventricle and Dramatically Reduces Infarct Size in Myocardial Infarction

    PubMed Central

    Kakino, Takamori; Arimura, Takahiro; Sakamoto, Takafumi; Nishikawa, Takuya; Sakamoto, Kazuo; Ikeda, Masataka; Kishi, Takuya; Ide, Tomomi; Sunagawa, Kenji

    2016-01-01

    Background Left ventricular assist device (LVAD) mechanically unloads the left ventricle (LV). Theoretical analysis indicates that partial LVAD support (p-LVAD), where LV remains ejecting, reduces LV preload while increases afterload resulting from the elevation of total cardiac output and mean aortic pressure, and consequently does not markedly decrease myocardial oxygen consumption (MVO2). In contrast, total LVAD support (t-LVAD), where LV no longer ejects, markedly decreases LV preload volume and afterload pressure, thereby strikingly reduces MVO2. Since an imbalance in oxygen supply and demand is the fundamental pathophysiology of myocardial infarction (MI), we hypothesized that t-LVAD minimizes MVO2 and reduces infarct size in MI. The purpose of this study was to evaluate the differential impact of the support level of LVAD on MVO2 and infarct size in a canine model of ischemia-reperfusion. Methods In 5 normal mongrel dogs, we examined the impact of LVAD on MVO2 at 3 support levels: Control (no LVAD support), p-LVAD and t-LVAD. In another 16 dogs, ischemia was induced by occluding major branches of the left anterior descending coronary artery (90 min) followed by reperfusion (300 min). We activated LVAD from the beginning of ischemia until 300 min of reperfusion, and compared the infarct size among 3 different levels of LVAD support. Results t-LVAD markedly reduced MVO2 (% reduction against Control: -56 ± 9%, p<0.01) whereas p-LVAD did less (-21 ± 14%, p<0.05). t-LVAD markedly reduced infarct size compared to p-LVAD (infarct area/area at risk: Control; 41.8 ± 6.4, p-LVAD; 29.1 ± 5.6 and t-LVAD; 5.0 ± 3.1%, p<0.01). Changes in creatine kinase-MB paralleled those in infarct size. Conclusions Total LVAD support that minimizes metabolic demand maximizes the benefit of LVAD in the treatment of acute myocardial infarction. PMID:27124411

  16. Selective endothelin A receptor antagonism with sitaxentan reduces neointimal lesion size in a mouse model of intraluminal injury

    PubMed Central

    Duthie, Karolina M; Hadoke, Patrick W F; Kirkby, Nicholas S; Miller, Eileen; Ivy, Jessica R; McShane, John F; Lim, Win Gel; Webb, David J

    2015-01-01

    Background and Purpose Endothelin (ET) receptor antagonism reduces neointimal lesion formation in animal models. This investigation addressed the hypothesis that the selective ETA receptor antagonist sitaxentan would be more effective than mixed ETA/B receptor antagonism at inhibiting neointimal proliferation in a mouse model of intraluminal injury. Experimental Approach Antagonism of ETA receptors by sitaxentan (1–100 nM) was assessed in femoral arteries isolated from adult, male C57Bl6 mice using isometric wire myography. Neointimal lesion development was induced by intraluminal injury in mice receiving sitaxentan (ETA antagonist; 15 mg·kg−1·day−1), A192621 (ETB antagonist; 30 mg·kg−1·day−1), the combination of both antagonists or vehicle. Treatment began 1 week before, and continued for 28 days after, surgery. Femoral arteries were then harvested for analysis of lesion size and composition. Key Results Sitaxentan produced a selective, concentration-dependent parallel rightward shift of ET-1-mediated contraction in isolated femoral arteries. Sitaxentan reduced neointimal lesion size, whereas ETB and combined ETA/B receptor antagonism did not. Macrophage and α-smooth muscle actin content were unaltered by ET receptor antagonism but sitaxentan reduced the amount of collagen in lesions. Conclusions and Implications These results suggest that ETA receptor antagonism would be more effective than combined ETA/ETB receptor antagonism at reducing neointimal lesion formation. PMID:25598351

  17. Reduced size of the amygdala in individuals with 47,XXY and 47,XXX karyotypes.

    PubMed

    Patwardhan, Anil J; Brown, Wendy E; Bender, Bruce G; Linden, Mary G; Eliez, Stephan; Reiss, Allan L

    2002-01-01

    The excess of 47,XXX and 47,XXY karyotypes found in cytogenetic screening studies of individuals with schizophrenia has given support for an increased risk of psychiatric illness among men and women with sex chromosomal aneuploidy (SCA). Mesial temporal lobe structures, including the amygdala and hippocampus, are thought to be associated with abnormalities of mood and behavior in humans and in the neurobiology of schizophrenia. This study focuses on variations in volumes of mesial temporal lobe structures in men and women with SCA. Utilizing an unselected birth cohort of subjects with SCA and high-resolution magnetic resonance imaging (MRI), we investigated the neuroanatomical consequences of a supernumerary X chromosome on the morphology of the amygdala and hippocampus. Regional and total brain volumes were measured in 10 subjects with 47,XXY, 10 subjects with 47,XXX, and 20 euploid controls. Amygdala volumes were significantly reduced in men with 47,XXY, compared to control men, while the decrease in women with 47,XXX was not as pronounced. Hippocampus volumes were preserved in both groups, compared to same-gender controls. Longitudinal studies of SCA individuals have shown an increased incidence of mild psychopathology and behavioral dysfunction in men with 47,XXY and more overt psychiatric illness in women with 47,XXX, compared to control populations. The alteration in amygdala volumes in individuals with a supernumerary X chromosome may provide a neuroanatomic basis for these findings.

  18. Anabolic steroids activate calcineurin-NFAT signaling and thereby increase myotube size and reduce denervation atrophy.

    PubMed

    Qin, Weiping; Pan, Jiangping; Wu, Yong; Bauman, William A; Cardozo, Christopher

    2015-01-01

    Anabolic androgens have been shown to reduce muscle loss due to immobilization, paralysis and many other medical conditions, but the molecular basis for these actions is poorly understood. We have recently demonstrated that nandrolone, a synthetic androgen, slows muscle atrophy after nerve transection associated with down-regulation of regulator of calcineurin 2 (RCAN2), a calcineurin inhibitor, suggesting a possible role of calcineurin-NFAT signaling. To test this possibility, rat gastrocnemius muscle was analyzed at 56 days after denervation. In denervated muscle, calcineurin activity declined and NFATc4 was excluded from the nucleus and these effects were reversed by nandrolone. Similarly, nandrolone increased calcineurin activity and nuclear NFATc4 levels in cultured L6 myotubes. Nandrolone also induced cell hypertrophy that was blocked by cyclosporin A or overexpression of RCAN2. Finally protection against denervation atrophy by nandrolone in rats was blocked by cyclosporin A. These results demonstrate for the first time that nandrolone activates calcineurin-NFAT signaling, and that such signaling is important in nandrolone-induced cell hypertrophy and protection against paralysis-induced muscle atrophy.

  19. Soluble epoxide hydrolase gene deletion improves blood flow and reduces infarct size after cerebral ischemia in reproductively senescent female mice

    PubMed Central

    Zuloaga, Kristen L.; Zhang, Wenri; Roese, Natalie E.; Alkayed, Nabil J.

    2015-01-01

    Soluble epoxide hydrolase (sEH), a key enzyme in the metabolism of vasodilatory epoxyeicosatrienoic acids (EETs), is sexually dimorphic, suppressed by estrogen, and contributes to underlying sex differences in cerebral blood flow and injury after cerebral ischemia. We tested the hypothesis that sEH inhibition or gene deletion in reproductively senescent (RS) female mice would increase cerebral perfusion and decrease infarct size following stroke. RS (15–18 month old) and young (3–4 month old) female sEH knockout (sEHKO) mice and wild type (WT) mice were subjected to 45 min middle cerebral artery occlusion (MCAO) with laser Doppler perfusion monitoring. WT mice were treated with vehicle or a sEH inhibitor t-AUCB at the time of reperfusion and every 24 h thereafter for 3 days. Differences in regional cerebral blood flow were measured in vivo using optical microangiography (OMAG). Infarct size was measured 3 days after reperfusion. Infarct size and cerebral perfusion 24 h after MCAO were not altered by age. Both sEH gene deletion and sEH inhibition increased cortical perfusion 24 h after MCAO. Neither sEH gene deletion nor sEH inhibition reduced infarct size in young mice. However, sEH gene deletion, but not sEH inhibition of the hydrolase domain of the enzyme, decreased infarct size in RS mice. Results of these studies show that sEH gene deletion and sEH inhibition enhance cortical perfusion following MCAO and sEH gene deletion reduces damage after ischemia in RS female mice; however this neuroprotection in absent is young mice. PMID:25642188

  20. Role of coagulation in the recruitment of colon adenocarcinoma cells to thrombus under shear

    PubMed Central

    Itakura, Asako; Gruber, András; McCarty, Owen J. T.

    2013-01-01

    Colorectal cancer metastases can appear on the peritoneum and in lymph nodes, liver, and lungs, suggesting both hematogenous and lymphatic spreading of the primary tumor. While antithrombotic agents have been shown to reduce both long-term incidence and metastasis, the role of coagulation in facilitating metastasis is ill defined. We investigated the kinetics and molecular mechanisms of metastatic colon adenocarcinoma cell recruitment to thrombi under shear flow, ex vivo. Platelet aggregates were formed by perfusing citrated anticoagulated whole blood over immobilized fibrinogen or fibrillar collagen. Thrombi were formed by perfusing recalcified whole blood over fibrinogen or fibrillar collagen in the presence of coagulation. Cultured colon adenocarcinoma cells (SW620) were perfused either during or following platelet aggregate or thrombus formation. The degree of transient tumor cell interactions (recruitment, rolling, and release) and the number of firmly adhered tumor cells were quantified using fluorescence microscopy. Platelet aggregates and thrombi formed on either fibrinogen- or fibrillar-collagen supported SW620 cell interactions and adhesion under shear. Thrombi or fibrin supported a greater degree of SW620 cell interactions and adhesion compared with platelet aggregates or fibrinogen, respectively, demonstrating that coagulation promoted SW620 cell recruitment under shear. Interestingly, in the absence of anticoagulation, we observed SW620 preferentially binding to thrombus-bound polymorphonuclear leukocytes (PMNs). The addition of purified PMNs to thrombi resulted in a doubling of the number of interacting and bound SW620 cells. Since thrombi often accumulate and activate leukocytes, our findings suggest that leukocytes may play a role in localizing metastases to sites of thrombogenesis. PMID:23903698

  1. Enhanced hydrogenation and reduced lattice distortion in size selected Pd-Ag and Pd-Cu alloy nanoparticles

    SciTech Connect

    Sengar, Saurabh K.; Mehta, B. R.; Kulriya, P. K.; Khan, S. A.

    2013-10-21

    Important correlation between valence band spectra and hydrogenation properties in Pd alloy nanoparticles is established by studying the properties of size selected and monocrystalline Pd, Ag, Cu, Pd-Ag, and Pd-Cu nanoparticles. The X-ray photoelectron spectroscopy and elastic recoil detection analysis show that size induced Pd4d centroid shift is related to enhanced hydrogenation with H/Pd ratio of 0.57 and 0.49 in Pd-Ag and Pd-Cu nanoparticles in comparison to reported bulk values of 0.2 and 0.1, respectively. Pd-alloy nanoparticles show lower hydrogen induced lattice distortion. The reduced distortion and higher hydrogen reactivity of Pd-alloy nanoparticles is important for numerous hydrogen related applications.

  2. Remediation of chromium-contaminated water using biogenic nano-sized materials and metal-reducing bacteria.

    PubMed

    Seo, Hyunhee; Sun, Eunyoung; Roh, Yul

    2013-06-01

    As an environmental nanotechnology, nano-sized materials have the potential to create novel and effective in-situ and ex-situ treatments for contaminated groundwater due to its high catalytic reactivity, large surface area, and dispersibility. In this study the efficiency of Cr(VI) reduction and immobilization using biotic and abiotic nano-sized materials (NSMs) and metal-reducing bacteria (MRB) was evaluated to remediate Cr(VI)-contaminated groundwater in batch and column tests. The results of this study revealed that the combination of the mixed MRB and bio-FeS/siderite performed the highest efficiency of Cr(VI) reduction and immobilization. Cr(VI) reduction by MRB and NSMs could impact on solubility of Cr(VI) and geochemical changes favorable for precipitation and adsorption.

  3. Efficacy of endoscopic variceal ligation for bleeding esophageal varices in patients with tumor thrombus of the portal vein trunk (Vp3) associated with hepatocellular carcinoma.

    PubMed

    Kokubu, S; Matsumoto, Y; Murakami, M; Shibata, H; Saigenji, K

    1997-04-01

    We studied the efficacy of endoscopic variceal ligation (EVL) in 16 patients with tumor thrombus of the portal vein trunk (Vp3) associated with hepatocellular carcinoma. The average (+/-SD) number of O rings used was 9.0 +/- 5.0 for the esophageal varices (n = 7) and 16.4 +/- 4.5 for the esophagogastric varices (n = 9). The variceal size was quickly reduced in 11 of the 13 cases whose therapeutic outcome was able to be assessed by endoscopy. The red color sign improved in 10 of the 13 cases, but the therapeutic end point (F0, RC-) was achieved in only two patients, who were also treated by endoscopic injection sclerotherapy. Emergency EVL achieved only short-term survival (17.14 +/- 6.64 days) and transient hemostasis. Elective EVL was associated with a survival duration of 90.0 +/- 64.25 days. The difference in the survival rate between emergency and elective cases was significant (P < .05). With regard to the timing of its application, EVL, being a less-invasive treatment, should be performed electively before variceal rebleeding for those patients with Vp3 hepatocellular carcinoma whose liver function is preserved. PMID:9151930

  4. The Effect of Size and Taper of Apical Preparation in Reducing Intra-Canal Bacteria: A Quantitative SEM Study

    PubMed Central

    Mohammadzadeh Akhlaghi, Nahid; Rahimifard, Nahid; Moshari, Amirabbas; Vatanpour, Mehdi; Darmiani, Soheila

    2014-01-01

    Introduction: Bacteria and their byproducts are major etiologic factors in endodontic diseases. Prevention or reduction of root canal bacterial contamination is the main aim of endodontic treatment. The purpose of this in vitro study was to evaluate the effect of size and taper of master apical file (MAF) in reducing bacteria from the apical third of the curved canals using a quantitative scanning electron microscope (SEM) study. Methods and Materials: Eighty-nine human mandibular first molars with curved MB canals (20º-35º) were divided into one control group (n=5) (without rotary instrumentation) and 6 experimental groups (n=14). The canals were prepared using RaCe rotary files to the MAF sizes 25/0.04, 25/0.06, 30/0.04, 30/0.06, 35/0.04 and 35/0.06, in groups 1 to 6, respectively. All the experimental groups were finally rinsed with 2 mL of 17% EDTA followed by 3 mL of 5.25% NaOCl. The mesial roots were split longitudinally. Remaining bacteria in the apical third of MB canals were evaluated using SEM (2000×). Data analysis was performed using one way ANOVA with Tukey’s post hoc test. The level of significance was set at 0.05. Results: All the experimental groups showed significant bacterial reduction (P<0.001). Although the greater size and/or taper resulted in decrease in bacteria, differences between the groups were not significant. Conclusion: Based on this in vitro study the MAF #25/0.04 had no significant difference compared to other groups with greater apical size/taper; all groups could effectively reduce intra-canal bacteria. PMID:24396378

  5. Use of High-Frequency In-Home Monitoring Data May Reduce Sample Sizes Needed in Clinical Trials

    PubMed Central

    Dodge, Hiroko H.; Zhu, Jian; Mattek, Nora C.; Austin, Daniel; Kornfeld, Judith; Kaye, Jeffrey A.

    2015-01-01

    individual-specific distributions of walking speed collected at baseline, 262 subjects are required. Similarly for computer use, 26 subjects are required. Conclusions Individual-specific thresholds of low functional performance based on high-frequency in-home monitoring data distinguish trajectories of MCI from NC and could substantially reduce sample sizes needed in dementia prevention RCTs. PMID:26379170

  6. Decoration of BiOI quantum size nanoparticles with reduced graphene oxide in enhanced visible-light-driven photocatalytic studies

    NASA Astrophysics Data System (ADS)

    Liu, Zhang; Xu, Weicheng; Fang, Jianzhang; Xu, Xiaoxin; Wu, Shuxing; Zhu, Ximiao; Chen, Zehua

    2012-10-01

    Herein, a reverse microemulsion route was developed to synthesize bismuth oxyiodide (BiOI) nanocrystals and reduced graphene oxide (RGO) nanocomposites as a highly efficient photocatalyst, and both the formation of BiOI and the reduction of RGO were achieved in situ in microemulsions simultaneously at low temperature (60 °C). The uniform nanocrystal size and structure were indicated by XRD, TEM, and the reduction of GO by ascorbic acid was evidenced by FTIR, XPS, and Raman spectra techniques. The enhanced photoactivity of RGO/BiOI nanocomposites under visible light was attributed to improved light absorption and efficient charge separation and transportation.

  7. Deletion of the presynaptic scaffold CAST reduces active zone size in rod photoreceptors and impairs visual processing.

    PubMed

    tom Dieck, Susanne; Specht, Dana; Strenzke, Nicola; Hida, Yamato; Krishnamoorthy, Vidhyasankar; Schmidt, Karl-Friedrich; Inoue, Eiji; Ishizaki, Hiroyoshi; Tanaka-Okamoto, Miki; Miyoshi, Jun; Hagiwara, Akari; Brandstätter, Johann H; Löwel, Siegrid; Gollisch, Tim; Ohtsuka, Toshihisa; Moser, Tobias

    2012-08-29

    How size and shape of presynaptic active zones are regulated at the molecular level has remained elusive. Here we provide insight from studying rod photoreceptor ribbon-type active zones after disruption of CAST/ERC2, one of the cytomatrix of the active zone (CAZ) proteins. Rod photoreceptors were present in normal numbers, and the a-wave of the electroretinogram (ERG)--reflecting their physiological population response--was unchanged in CAST knock-out (CAST(-/-)) mice. Using immunofluorescence and electron microscopy, we found that the size of the rod presynaptic active zones, their Ca(2+) channel complement, and the extension of the outer plexiform layer were diminished. Moreover, we observed sprouting of horizontal and bipolar cells toward the outer nuclear layer indicating impaired rod transmitter release. However, rod synapses of CAST(-/-) mice, unlike in mouse mutants for the CAZ protein Bassoon, displayed anchored ribbons, normal vesicle densities, clustered Ca(2+) channels, and essentially normal molecular organization. The reduction of the rod active zone size went along with diminished amplitudes of the b-wave in scotopic ERGs. Assuming, based on the otherwise intact synaptic structure, an unaltered function of the remaining release apparatus, we take our finding to suggest a scaling of release rate with the size of the active zone. Multielectrode-array recordings of retinal ganglion cells showed decreased contrast sensitivity. This was also observed by optometry, which, moreover, revealed reduced visual acuity. We conclude that CAST supports large active zone size and high rates of transmission at rod ribbon synapses, which are required for normal vision.

  8. Using a Reduced Spot Size for Intensity-Modulated Proton Therapy Potentially Improves Salivary Gland-Sparing in Oropharyngeal Cancer

    SciTech Connect

    Water, Tara A. van de; Lomax, Antony J.; Bijl, Hendrik P.; Schilstra, Cornelis; Hug, Eugen B.; Langendijk, Johannes A.

    2012-02-01

    Purpose: To investigate whether intensity-modulated proton therapy with a reduced spot size (rsIMPT) could further reduce the parotid and submandibular gland dose compared with previously calculated IMPT plans with a larger spot size. In addition, it was investigated whether the obtained dose reductions would theoretically translate into a reduction of normal tissue complication probabilities (NTCPs). Methods: Ten patients with N0 oropharyngeal cancer were included in a comparative treatment planning study. Both IMPT plans delivered simultaneously 70 Gy to the boost planning target volume (PTV) and 54 Gy to the elective nodal PTV. IMPT and rsIMPT used identical three-field beam arrangements. In the IMPT plans, the parotid and submandibular salivary glands were spared as much as possible. rsIMPT plans used identical dose-volume objectives for the parotid glands as those used by the IMPT plans, whereas the objectives for the submandibular glands were tightened further. NTCPs were calculated for salivary dysfunction and xerostomia. Results: Target coverage was similar for both IMPT techniques, whereas rsIMPT clearly improved target conformity. The mean doses in the parotid glands and submandibular glands were significantly lower for three-field rsIMPT (14.7 Gy and 46.9 Gy, respectively) than for three-field IMPT (16.8 Gy and 54.6 Gy, respectively). Hence, rsIMPT significantly reduced the NTCP of patient-rated xerostomia and parotid and contralateral submandibular salivary flow dysfunction (27%, 17%, and 43% respectively) compared with IMPT (39%, 20%, and 79%, respectively). In addition, mean dose values in the sublingual glands, the soft palate and oral cavity were also decreased. Obtained dose and NTCP reductions varied per patient. Conclusions: rsIMPT improved sparing of the salivary glands and reduced NTCP for xerostomia and parotid and submandibular salivary dysfunction, while maintaining similar target coverage results. It is expected that rsIMPT improves quality

  9. Mercury induces proliferation and reduces cell size in vascular smooth muscle cells through MAPK, oxidative stress and cyclooxygenase-2 pathways

    SciTech Connect

    Aguado, Andrea; Galán, María; Zhenyukh, Olha; Wiggers, Giulia A.; Roque, Fernanda R.; Redondo, Santiago; Peçanha, Franck; Martín, Angela; Fortuño, Ana; Cachofeiro, Victoria; Tejerina, Teresa; Salaices, Mercedes; and others

    2013-04-15

    MAPK activation, oxidative stress and COX-2 expression. ► Inhibition of MAPK reduces HgCl{sub 2}-induced oxidative stress and COX-2 expression. ► Inhibition of MAPK, oxidative stress and COX-2 restores the altered cell proliferation and size.

  10. Reduced neuronal size and mTOR pathway activity in the Mecp2 A140V Rett syndrome mouse model

    PubMed Central

    Rangasamy, Sampathkumar; Olfers, Shannon; Gerald, Brittany; Hilbert, Alex; Svejda, Sean; Narayanan, Vinodh

    2016-01-01

    Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutation in the X-linked MECP2 gene, encoding methyl-CpG-binding protein 2. We have created a mouse model ( Mecp2 A140V “knock-in” mutant) expressing the recurrent human MECP2 A140V mutation linked to an X-linked mental retardation/Rett syndrome phenotype. Morphological analyses focused on quantifying soma and nucleus size were performed on primary hippocampus and cerebellum granule neuron (CGN) cultures from mutant ( Mecp2 A140V/y) and wild type ( Mecp2 +/y) male mice. Cultured hippocampus and cerebellar granule neurons from mutant animals were significantly smaller than neurons from wild type animals. We also examined soma size in hippocampus neurons from individual female transgenic mice that express both a mutant  (maternal allele) and a wild type Mecp2 gene linked to an eGFP transgene (paternal allele). In cultures from such doubly heterozygous female mice, the size of neurons expressing the mutant (A140V) allele also showed a significant reduction compared to neurons expressing wild type MeCP2, supporting a cell-autonomous role for MeCP2 in neuronal development. IGF-1 (insulin growth factor-1) treatment of neuronal cells from Mecp2 mutant mice rescued the soma size phenotype. We also found that Mecp2   mutation leads to down-regulation of the mTOR signaling pathway, known to be involved in neuronal size regulation. Our results suggest that i) reduced neuronal size is an important in vitro cellular phenotype of Mecp2 mutation in mice, and ii) MeCP2 might play a critical role in the maintenance of neuronal structure by modulation of the mTOR pathway. The definition of a quantifiable cellular phenotype supports using neuronal size as a biomarker in the development of a high-throughput, in vitro assay to screen for compounds that rescue small neuronal phenotype (“phenotypic assay”). PMID:27781091

  11. The evaluation of anti-angiogenic effects of Endostar on rabbit VX2 portal vein tumor thrombus using perfusion MSCT

    PubMed Central

    2014-01-01

    Background There were many treatments for hepatocellular carcinoma with portal vein tumor thrombus (PVTT), in which targeted anti-angiogenic drug therapy is becoming a popular research topic. However, an objective and non-invasive method that can evaluate the treatment effects is still lacking. Methods Eighteen New Zealand white rabbits implanted with VX2 tumor thrombus in portal vein were randomly assigned into 3 groups: Endostar, saline, or control, six in each group. Multi-slice CT (MSCT) perfusion scanning was performed to measure the differences in blood flow (TBF), tissue blood volume (TBV), and capillary permeability time the surface (PS) before and after Endostar treatment, between Endostar and saline treatment. Two weeks after treatment, both Endostar and saline groups underwent CT perfusion scan. The rabbits then were sacrificed by air embolism, and specimens of tumor thrombosis were collected. Immunohistochemistry assay was also performed to compare the expression of vascular endothelial growth factor (VEGF) in PVTT after Endostar, saline and placebo treatment. Results In Endostar group, PVTT CT perfusion parameters (TBF, TBV, PS) significantly decreased after the treatment (p <0.05). Post-treatment PVTT CT perfusion parameters (TBF, TBV, PS) were significantly lower in Endostar group than in Saline group (p <0.05). VEGF is mainly expressed in cytoplasma. After Endostar treatment, the expression of VEGF in PVTT was markedly reduced. There was also significant difference on post-treatment VEGF protein expression measured by Immunohistochemistry assay between Endostar group and control group (p <0.05). Post-treatment PVTT CT perfusion parameters (TBF, TBV, PS) were positively correlated with VEGF protein expression in all 3 groups (rs > 0, p <0.05). Conclusions Multi-slice CT perfusion imaging can evaluate the anti-angiogenic effects of Endostar for the VX2 tumor thrombus in portal vein, and provide quantitative functional information. PMID:25608952

  12. No-Reflow Phoenomenon by Intracoronary Thrombus in Acute Myocardial Infarction

    PubMed Central

    2016-01-01

    Recently, percutaneous coronary intervention has been the treatment of choice in most acute myocardial infarction cases. Although the results of percutaneous coronary interventions have ben good, the no-reflow phenomenon and distal embolization of intracoronary thrombus are still major problems even after successful interventions. In this article, we will briefly review the deleterious effects of no-reflow and distal embolization of intracoronary thrombus during percutaneous coronary interventions. The current trials focused on the prevention and treatment of the no-reflow phenomenon and intracoronary thrombus. PMID:26865998

  13. Percutaneous coronary intervention for three vessels of chronic total occlusion complicated with huge left ventricular thrombus.

    PubMed

    Hashimoto, Sho; Shiraishi, Jun; Yanagiuchi, Takashi; Hyogo, Masayuki; Sawada, Takahisa; Kohno, Yoshio

    2016-10-01

    A 55-year-old woman with symptoms of heart failure appeared to have ischemic cardiomyopathy complicated with 3-vessel chronic total occlusion (CTO), severely deteriorated left ventricular (LV) function, and large LV thrombus. Because of high risk of surgical thrombectomy in addition to coronary artery bypass grafting surgery, we first confirmed significant reduction of LV thrombus and performed percutaneous coronary intervention against the 3-vessel CTO under preceding anticoagulation therapy with warfarin, aspirin, and clopidogrel. By means of antegrade/retrograde approach, we successfully implanted everolimus-eluting stents one by one, leading to complete revascularization, dramatically improved LV function, and disappearance of LV thrombus without post-procedural embolism.

  14. Left ventricular thrombus formation after repair of anomalous left coronary artery from the pulmonary artery.

    PubMed

    Freud, Lindsay R; Koenig, Peter R; Russell, Hyde M; Patel, Angira

    2014-04-01

    Although thrombus formation following myocardial infarction in adults is well known, intracardiac thrombosis in children is uncommon. We report the case of a large left ventricular thrombus in an infant with ischemic cardiomyopathy secondary to anomalous origin of the left coronary artery from the pulmonary artery. Given its mobility and protrusion across the aortic valve, the patient underwent urgent thrombus removal through a transaortic approach. There were no embolic or neurologic complications. This case highlights that thrombectomy may be performed safely and successfully in critically ill pediatric patients.

  15. A Case Report of Carbon Monoxide Poisoning Induced Cardiomyopathy Complicated with Left Ventricular Thrombus

    PubMed Central

    Lee, Seung-Jae; Kang, Ju-Hyun; Kim, Nam-Yong; Baek, In-Woon; Park, Mi-Youn; Shim, Byung-Ju; Koh, Yoon-Seok; Shin, Woo-Seung; Lee, Jong-Min

    2011-01-01

    The heart and the brain, most oxygen-dependent organs, may be severely affected after carbon monoxide (CO) exposure. CO induced cardiotoxicity may occur as a consequence of moderate to severe CO poisoning, including angina attack, myocardial infarct, arrhythmias, and heart failure. We present a rare case of CO poisoning induced cardiomyopathy with left ventricular (LV) thrombus. It is thought that LV thrombus may have been caused severely decreased LV function with dyskinesis. After short-term anticoagulant therapy, echocardiography findings revealed complete recovery of LV dyskinesis and resolution of LV thrombus. PMID:21860722

  16. Reduced survival and body size in the terrestrial isopod Porcellio scaber from a metal-polluted environment.

    PubMed

    Jones, D T; Hopkin, S P

    1998-01-01

    Terrestrial isopods (woodlice) may show trade-offs in life history parameters when exposed to toxins. We have shown previously [Jones and Hopkin (1996) Functional Ecology 10, 741-750] that woodlice which survive to reproduce in sites heavily polluted with metals from an industrial smelting works do not alter their reproductive allocation. This study investigates whether there are differences in the survival and body size of Porcellio scaber from these same populations. Specimens were collected from eight sites at different distances from the Avonmouth smelter, UK. The sites represented a gradient of concentrations of Zn, Cd, Pb and Cu in the woodlice, from background levels to a grossly contaminated sites close to the smelter. In laboratory trials, the number of days survived by starved males showed a significant decline with increased concentrations of Zn in those animals. The maximum size of both sexes declined significantly from the least to the most polluted sites. The most polluted sites had significantly fewer large animals. The cost of detoxifying assimilated metals appears to be reduced energy reserves and smaller body size.

  17. Comparative efficacies of oral ketoconazole and terbinafine for reducing Malassezia population sizes on the skin of Basset Hounds.

    PubMed

    Guillot, Jacques; Bensignor, Emmanuel; Jankowski, François; Seewald, Wolfgang; Chermette, René; Steffan, Jean

    2003-06-01

    The objective of this study was to compare the efficacy of oral ketoconazole and terbinafine for reducing population sizes of Malassezia yeasts on canine skin. Twenty-one Basset Hounds were randomised in three groups of seven according to Malassezia populations. Dogs in the first group were treated by oral administration of ketoconazole (Ketofungol) 200 mg, Janssen-Cilag) at 10 mg x kg-1, every 24 h with food, for 3 weeks. Dogs in the second group were treated by oral administration of terbinafine (Lamisil) 250 mg, Novartis) at 30 mg x kg-1, every 24 h with food, for 3 weeks. The seven remaining dogs were used as controls. Malassezia population sizes were assessed by use of contact plates on four cutaneous sites at days 7, 14 and 21. Both ketoconazole and terbinafine were effective in reducing the baseline levels of Malassezia organisms with no significant difference between the two drugs. In further studies, oral terbinafine should be evaluated for the management of canine cases of Malassezia dermatitis. PMID:12791049

  18. High-resolution MRI characterization of human thrombus using a novel fibrin-targeted paramagnetic nanoparticle contrast agent.

    PubMed

    Yu, X; Song, S K; Chen, J; Scott, M J; Fuhrhop, R J; Hall, C S; Gaffney, P J; Wickline, S A; Lanza, G M

    2000-12-01

    In this study, the sensitivity of a novel fibrin-targeted contrast agent for fibrin detection was defined in vitro on human thrombus. The contrast agent was a lipid-encapsulated perfluorocarbon nanoparticle with numerous Gd-DTPA complexes incorporated into the outer surface. After binding to fibrin clots, scanning electron microscopy of treated clots revealed dense accumulation of nanoparticles on the clot surfaces. Fibrin clots with sizes ranging from 0.5-7.0 mm were imaged at 4.7 T with or without treatment with the targeted contrast agent. Regardless of sizes, untreated clots were not detectable by T(1)-weighted MRI, while targeted contrast agent dramatically improved the detectability of all clots. Decreases in T(1) and T(2) relaxation times (20-40%) were measured relative to the surrounding media and the control clots. These results suggest the potential for sensitive and specific detection of microthrombi that form on the intimal surfaces of unstable atherosclerotic plaque.

  19. 3′,4′-Dihydroxyflavonol reduces infarct size and injury associated with myocardial ischaemia and reperfusion in sheep

    PubMed Central

    Wang, Sheng; Dusting, Gregory J; May, Clive N; Woodman, Owen L

    2004-01-01

    The antioxidant properties of flavonols in vivo and their potential benefits in myocardial ischaemia/reperfusion (I/R) injury have been little investigated. We evaluated the ability of a synthetic flavonol, 3′,4′-dihydroxyflavonol (DiOHF) to scavenge superoxide in post-I/R myocardium and to prevent myocardial I/R injury. Anaesthetized sheep were studied in four groups (n=5–6): control, ischaemic preconditioning (IPC), vehicle and DiOHF (before reperfusion, 5 mg kg−1, i.v.). The left anterior descending coronary artery was occluded distal to the second diagonal branch for 1 h followed by 2 h of reperfusion. Infarct size, myocardial function, NADPH-activated superoxide generation and biochemical markers of injury were measured. DiOHF (10−8–10−4 M) incubated in vitro with post-I/R myocardium from the vehicle group suppressed superoxide production dose-dependently. DiOHF administered in vivo also significantly reduced superoxide generation in vitro. DiOHF and IPC markedly reduced infarct size, which was 73±2% of the area at risk in vehicle, 50±4% in DiOHF, 75±5% in control and 44±4% in IPC. Post-I/R segment shortening within the ischaemic zone was greater in DiOHF (2.3±0.7%; P<0.01) and IPC (1.7±0.5%; P<0.01) than those in corresponding controls (−1.7±0.4; −2.1±0.4%). DiOHF and IPC improved coronary blood flow to the ischaemic area and preserved higher levels of nitric oxide metabolites in the venous outflow from the ischaemic zone. DiOHF attenuated superoxide production in post-I/R myocardium, and significantly reduced infarct size and injury following I/R in anaesthetized sheep. The extent of protection by DiOHF is comparable to that afforded by IPC. Thus, DiOHF has clinical potential for improving recovery from acute myocardial infarction and other ischaemic syndromes. PMID:15148246

  20. [Successful direct thrombin inhibitor treatment of a left atrial appendage thrombus developed under rivaroxaban therapy].

    PubMed

    Szegedi, Nándor; Gellér, László; Tahin, Tamás; Merkely, Béla; Széplaki, Gábor

    2016-01-24

    The authors present the history of a 62-year-old man on continuous rivaroxaban therapy who was scheduled for pulmonary vein isolation due to persistent atrial fibrillation. Preoperative transesophageal echocardiography detected the presence of left atrial appendage thrombus. Thrombophilia tests showed that the patient was heterozygous carrier of the methylene-tetrahydrofolate reductase gene mutation. The authors hypothesized that a direct thrombin inhibitor might exert a more appropriate effect against thrombosis in this case and, therefore, a switch to dabigatran was performed. After two months of anticoagulation with the direct thrombin inhibitor and folic acid supplementation the thrombus resolved. The authors underline that thrombus formation may develop in atrial fibrillation even if the patient is adequately treated with rivaroxaban. This case suggests, that methylene-tetrahydrofolate reductase gene mutation may modulate the efficacy of direct Xa factor inhibitors. According to this case history, dabigatran may be an effective therapeutic option in resolving established thrombus.

  1. Mechano-rheological properties of the murine thrombus determined via nanoindentation and finite element modeling.

    PubMed

    Slaboch, Constance L; Alber, Mark S; Rosen, Elliot D; Ovaert, Timothy C

    2012-06-01

    Deep vein thrombosis, pulmonary embolism, and abdominal aortic aneurysms are blood-related diseases that represent a major public health problem. These diseases are characterized by the formation of a thrombus (i.e., blood clot) that either blocks a major artery or causes an aortic rupture. Identifying the mechanical properties of thrombi can help determine when these incidents will occur. In this investigation, a murine thrombus, formed from platelet-rich plasma, calcium, and thrombin, was nanoindented and the elastic modulus was estimated via elastic contact theory. This information was used as input to an inverse finite element simulation, which determined optimal values for the elastic modulus and viscosity of the thrombus using a viscoelastic material model. A sensitivity analysis was also performed to determine which material parameters have the greatest affect on the simulation. Results from this investigation demonstrate the feasibility of the mechanical characterization of a murine thrombus using nanoindentation. PMID:22520420

  2. A case report of retroaortic left renal vein with tumor thrombus of renal cell carcinoma.

    PubMed

    Otsuki, Hideo; Kuroda, Kenji; Kosaka, Takeo; Ito, Keiichi; Hayakawa, Masamichi; Asano, Tomohiko

    2011-06-01

    A 75-year-old woman was referred to our department for evaluation of a left renal tumor. Computed tomography and other imaging studies demonstrated a left renal mass and tumor extension into the left renal vein passing caudally behind the aorta. We clinically diagnosed the tumor as renal cell carcinoma (RCC) associated with a retroaortic left renal vein thrombus, and performed a radical nephrectomy. Pathological examination of the surgical specimen showed a grade 2, clear cell carcinoma with a renal vein thrombus and negative surgical margin. Retroaortic left renal vein is a rare anomaly with a prevalence of 1.8-2.4%. RCC associated with a retroaortic left renal vein thrombus is rarer still. To our knowledge, this is only the third case report to describe an RCC associated with a tumor thrombus in the retroaortic left renal vein.

  3. Eyelid varix with phlebolith formation, thrombus recanalization, and early intravascular papillary endothelial hyperplasia.

    PubMed

    Zakka, Fouad R; Jakobiec, Frederick A; Thakker, Manoj M

    2011-01-01

    An asymptomatic, bluish-gray, movable, raised, and firm left upper eyelid mass had been present for 8 months in an 82-year-old woman. Histopathologic examination revealed a lesion restricted to the dermis and composed in part of a calcific nodule that was circumscribed by an acellular fibrous capsule. An adjacent nodule exhibited proliferating endothelial cells invading a fresh thrombus. Immunohistochemical staining revealed positivity for CD31, CD34, and CD68; D2-40 was negative, ruling out a lymphatic origin. Masson trichrome and elastic staining of deeper sections revealed recanalization of an earlier thrombus; surviving elastic fibers were discovered in the outer wall, establishing a venous source. This is the first reported case of 3 microscopically discernible events (old phlebolith, fresh intravascular endothelial hyperplasia invading a thrombus, and labyrinthine recanalization of a temporally more remote thrombus) in an eyelid varix. The clinical differential diagnosis is reviewed. PMID:20724862

  4. Novel Percutaneous Radiofrequency Ablation of Portal Vein Tumor Thrombus: Safety and Feasibility

    SciTech Connect

    Mizandari, Malkhaz; Ao, Guokun; Zhang Yaojun; Feng Xi; Shen Qiang; Chen Minshan; Lau, Wan Yee; Nicholls, Joanna; Jiao Long; Habib, Nagy

    2013-02-15

    We report our experience of the safety of partial recanalization of the portal vein using a novel endovascular radiofrequency (RF) catheter for portal vein tumor thrombosis. Six patients with liver cancer and tumor thrombus in the portal vein underwent percutaneous intravascular radiofrequency ablation (RFA) using an endovascular bipolar RF device. A 0.035-inch guidewire was introduced into a tributary of the portal vein and through which a 5G guide catheter was introduced into the main portal vein. After manipulation of the guide catheter over the thrombus under digital subtraction angiography, the endovascular RF device was inserted and activated around the thrombus. There were no observed technique specific complications, such as hemorrhage, vessel perforation, or infection. Post-RFA portography showed partial recanalization of portal vein. RFA of portal vein tumor thrombus in patients with hepatocellular carcinoma is technically feasible and warrants further investigation to assess efficacy compared with current recanalization techniques.

  5. Fatal evolution of a huge right atrial free-floating thrombus

    PubMed Central

    Bodian, Malick; Ba, Fatimata G; Jobe, Modou; Ndiaye, Mouhamadou B; Kane, Adama; Sarr, Simon A; Mbaye, Alassane; Gaye, Abdou M; Thiam, Ibou; Diao, Maboury; Sarr, Moustapha; Bâ, Serigne A

    2013-01-01

    Key Clinical Message Right atrial thrombus is a rare medical emergency that should be suspected in all cases of pulmonary embolism, and rapid action should be taken to ensure a timely, proper management. PMID:25356214

  6. Une angiocholite secondaire à un thrombus tumoral d'une tumeur neuroendocrine primitive du foie

    PubMed Central

    Baba, Hicham; Allaoui, Mohamed; Elfahssi, Mohammed; Bounaim, Ahmed; Ali, Abdelmounaim Ait; Oukabli, Mohamed; Sair, Khalid; Zentar, Aziz

    2015-01-01

    Nous rapportons le cas exceptionnel d'une patiente de 54 ans prise en charge pour une angiocholite due à un thrombus tumoral, d'une tumeur neuroendocrine primitive (TNE Ive) du foie, dans la voie biliaire principale. PMID:26966504

  7. Size-Controlled Synthesis of Copper Oxide Particles on Reduced Graphene Oxide for Lithium-Ion Battery Anode Applications.

    PubMed

    Jang, Haneul; Kim, Kyungbae; Chang, Hyejung; Kim, Jae-Hun; Choi, Hyunjoo

    2015-11-01

    Copper oxide/reduced graphene oxide (rGO) hybrids have been successfully synthesized by attaching copper ions onto the functional groups of GO by means of a solution process, which causes precipitation and agglomeration of copper oxides during subsequent thermal reduction of the GO. The resulting copper oxide/rGO hybrid exhibited improved electrochemical performance compared to monolithic CuO, which is presumed to be due to rGO acting as a mechanical support that buffers the volume change in copper oxides that occurs as a result of the conversion reaction during charge/discharge cycling. Furthermore, it was found that the size of the copper oxide particles can be optimized by adjusting the annealing time, with a hybrid annealed for 30 min achieving a reversible capacity of 544 mA h g(-1) and an initial coulombic efficiency of 62.7%.

  8. Computational Study of Thrombus Formation and Clotting Factor Effects under Venous Flow Conditions.

    PubMed

    Govindarajan, Vijay; Rakesh, Vineet; Reifman, Jaques; Mitrophanov, Alexander Y

    2016-04-26

    A comprehensive understanding of thrombus formation as a physicochemical process that has evolved to protect the integrity of the human vasculature is critical to our ability to predict and control pathological states caused by a malfunctioning blood coagulation system. Despite numerous investigations, the spatial and temporal details of thrombus growth as a multicomponent process are not fully understood. Here, we used computational modeling to investigate the temporal changes in the spatial distributions of the key enzymatic (i.e., thrombin) and structural (i.e., platelets and fibrin) components within a growing thrombus. Moreover, we investigated the interplay between clot structure and its mechanical properties, such as hydraulic resistance to flow. Our model relied on the coupling of computational fluid dynamics and biochemical kinetics, and was validated using flow-chamber data from a previous experimental study. The model allowed us to identify the distinct patterns characterizing the spatial distributions of thrombin, platelets, and fibrin accumulating within a thrombus. Our modeling results suggested that under the simulated conditions, thrombin kinetics was determined predominantly by prothrombinase. Furthermore, our simulations showed that thrombus resistance imparted by fibrin was ∼30-fold higher than that imparted by platelets. Yet, thrombus-mediated bloodflow occlusion was driven primarily by the platelet deposition process, because the height of the platelet accumulation domain was approximately twice that of the fibrin accumulation domain. Fibrinogen supplementation in normal blood resulted in a nonlinear increase in thrombus resistance, and for a supplemented fibrinogen level of 48%, the thrombus resistance increased by ∼2.7-fold. Finally, our model predicted that restoring the normal levels of clotting factors II, IX, and X while simultaneously restoring fibrinogen (to 88% of its normal level) in diluted blood can restore fibrin generation to

  9. Clinorotation reduces number, but not size, of cartilaginous nodules formed in micromass cultures of mouse limbbud cells

    NASA Astrophysics Data System (ADS)

    Duke, P. J.; Montufar-Solis, D.; Hamazaki, T.; Sato, A.

    In previous studies we used a ground based model to investigate the cellular responses to microgravity by exposing micromass cultures of embryonic limb cells to simulated weightlessness on a clinostat. Cultures set up in T-flasks and rotated at 30 rpm showed that clinostatted cultures had less chondrocyte differentiation than stationary or rotation controls, as assessed by number of nodules/culture stained with cartilage specific Alcian blue. In the current study, nodule size and shape of these nodules was assessed by interactive measurement of area, perimeter, circularity, and equivalent diameters, using the Optimas imaging software. Results show no significant difference in any of the measurements, indicating that clinorotation has no effect on expansion of the nodules either by differentiation of cells within the nodule, or by recruitment of cells into the nodule. The reduction in number of nodules without an alteration in size and shape indicates that the effect of simulated microgravity is to reduce the cell interactions required for the initial condensation of cells into a nodule, probably by interference with cell adhesion molecules.

  10. Evaluation and Management of Plaque Protrusion or Thrombus following Carotid Artery Stenting

    PubMed Central

    HASHIMURA, Naoki; MUTOH, Tatsushi; MATSUDA, Kazuya; MATSUMOTO, Keigo

    2015-01-01

    Carotid artery stenting (CAS) has become a common treatment for carotid artery stenosis. However, complications, such as an ischemic event, can occur with CAS during intra- and post-operative periods. Among these ischemic complications, plaque protrusion into the stent and thrombus on the stent have occurred after CAS. We retrospectively evaluated the temporal profile and treatment options for these complications in 32 consecutive cases who underwent CAS at our hospital between April 2009 and December 2011. The cases were evaluated pre-operatively for risk factors, as well as the plaque morphology and characteristics using computed tomographic angiography (CTA), ultrasound (US), and magnetic resonance imaging (MRI). Post-operatively, lesions were examined by CTA and/or US within 1 week of CAS. As a result, among the 32 cases, 8 experienced plaque protrusions or thrombus, which were treated with medication (anti-platelet and/or anti-coagulation reinforcement). In 7 of these 8 cases, the plaque protrusion or thrombus was stabilized with medication alone. However, the remaining case showed growth and migration of the plaque protrusion or thrombus when treated with medication alone, and therefore, required further endovascular treatment. We identified that a history of symptomatic cerebral infarction and plaques with ulceration were risk factors for plaque protrusion or thrombus formation after CAS, and pre dilatation can decrease the risk of these complications. Medication was effective in most cases of plaque protrusion or thrombus; however, further endovascular treatment was required when medication alone was unsuccessful. PMID:25746309

  11. Histological and Biomechanical Changes in a Mouse Model of Venous Thrombus Remodeling

    PubMed Central

    Lee, Y.-U.; Lee, A.Y.; Humphrey, J.D.; Rausch, M.K.

    2016-01-01

    BACKGROUND Deep vein thrombosis and the risk of pulmonary embolism are significant causes of morbidity and mortality. Much remains unclear, however, about the mechanisms by which a venous thrombus initiates, progresses, or resolves. In particular, there is a pressing need to characterize the evolving mechanical properties of a venous thrombus for its mechanical integrity is fundamental to many disease sequelae. OBJECTIVE The primary goal of the present study was to initiate a correlation between evolving histological changes and biomechanical properties of venous thrombus. METHODS We employed an inferior vena cava ligation model in mice to obtain cylindrical samples of thrombus that were well suited for mechanical testing and that could be explanted at multiple times following surgery. Using uniaxial micro-mechanical testing, we collected stress-stretch data that were then fit with a microstructurally-inspired material model before submitting the samples to immunohistological examination. RESULTS We found that venous thrombus underwent a radially inward directed replacement of fibrin with collagen between 2 weeks and 4 weeks of development, which was accompanied by the infiltration of inflammatory and mesenchymal cells. These histological changes correlated with a marked increase in material stiffness. CONCLUSIONS We demonstrated that 2 to 4 week old venous thrombus undergoes drastic remodeling from a fibrin-dominated mesh to a collagen-dominated microstructure and that these changes are accompanied by dramatic changes in biomechanical behavior. PMID:26444224

  12. The influence of intraluminal thrombus on noninvasive abdominal aortic aneurysm wall distensibility measurement.

    PubMed

    Metaxa, Eleni; Kontopodis, Nikolaos; Vavourakis, Vasileios; Tzirakis, Konstantinos; Ioannou, Christos V; Papaharilaou, Yannis

    2015-04-01

    Abdominal aortic aneurysm wall distensibility can be estimated by measuring pulse pressure and the corresponding sac volume change, which can be obtained by measuring wall displacement. This approach, however, may introduce error if the role of thrombus in assisting the wall in bearing the pulse pressure loading is neglected. Our aim was to introduce a methodology for evaluating and potentially correcting this error in estimating distensibility. Electrocardiogram-gated computed tomography images of eleven patients were obtained, and the volume change between diastole and systole was measured. Using finite element procedures, we determined the equivalent pulse pressure loading that should be applied to the wall of a model where thrombus was digitally removed, to yield the same sac volumetric increase caused by applying the luminal pulse pressure to the model with thrombus. The equivalent instead of the measured pulse pressure was used in the distensibility expression. For a relative volumetric thrombus deposition (V ILT) of 50 %, a 62 % distensibility underestimation resulted when thrombus role was neglected. A strong linear correlation was observed between distensibility underestimation and V ILT. To assess the potential value of noninvasive wall distensibility measurement in rupture risk stratification, the role of thrombus on wall loading should be further investigated. PMID:25548097

  13. Methods to Determine the Lagrangian Shear Experienced by Platelets during Thrombus Growth.

    PubMed

    Pinar, Isaac P; Arthur, Jane F; Andrews, Robert K; Gardiner, Elizabeth E; Ryan, Kris; Carberry, Josie

    2015-01-01

    Platelets can become activated in response to changes in flow-induced shear; however, the underlying molecular mechanisms are not clearly understood. Here we present new techniques for experimentally measuring the flow-induced shear rate experienced by platelets prior to adhering to a thrombus. We examined the dynamics of blood flow around experimentally grown thrombus geometries using a novel combination of experimental (ex vivo) and numerical (in silico) methodologies. Using a microcapillary system, platelet aggregate formation was analysed at elevated shear rates in the presence of coagulation inhibitors, where thrombus formation is predominantly platelet-dependent. These approaches permit the resolution and quantification of thrombus parameters at the scale of individual platelets (2 μm) in order to quantify real time thrombus development. Using our new techniques we can correlate the shear rate experienced by platelets with the extent of platelet adhesion and aggregation. The techniques presented offer the unique capacity to determine the flow properties for a temporally evolving thrombus field in real time. PMID:26660525

  14. Methods to Determine the Lagrangian Shear Experienced by Platelets during Thrombus Growth

    PubMed Central

    Pinar, Isaac P.; Arthur, Jane F.; Andrews, Robert K.; Gardiner, Elizabeth E.; Ryan, Kris; Carberry, Josie

    2015-01-01

    Platelets can become activated in response to changes in flow-induced shear; however, the underlying molecular mechanisms are not clearly understood. Here we present new techniques for experimentally measuring the flow-induced shear rate experienced by platelets prior to adhering to a thrombus. We examined the dynamics of blood flow around experimentally grown thrombus geometries using a novel combination of experimental (ex vivo) and numerical (in silico) methodologies. Using a microcapillary system, platelet aggregate formation was analysed at elevated shear rates in the presence of coagulation inhibitors, where thrombus formation is predominantly platelet-dependent. These approaches permit the resolution and quantification of thrombus parameters at the scale of individual platelets (2 μm) in order to quantify real time thrombus development. Using our new techniques we can correlate the shear rate experienced by platelets with the extent of platelet adhesion and aggregation. The techniques presented offer the unique capacity to determine the flow properties for a temporally evolving thrombus field in real time. PMID:26660525

  15. Modest hypoxia significantly reduces triglyceride content and lipid droplet size in 3T3-L1 adipocytes

    SciTech Connect

    Hashimoto, Takeshi; Yokokawa, Takumi; Endo, Yuriko; Iwanaka, Nobumasa; Higashida, Kazuhiko; Taguchi, Sadayoshi

    2013-10-11

    Highlights: •Long-term hypoxia decreased the size of LDs and lipid storage in 3T3-L1 adipocytes. •Long-term hypoxia increased basal lipolysis in 3T3-L1 adipocytes. •Hypoxia decreased lipid-associated proteins in 3T3-L1 adipocytes. •Hypoxia decreased basal glucose uptake and lipogenic proteins in 3T3-L1 adipocytes. •Hypoxia-mediated lipogenesis may be an attractive therapeutic target against obesity. -- Abstract: Background: A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function. Methods: Differentiated 3T3-L1 adipocytes were incubated at 5% O{sub 2} for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC). Results: HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01). Conclusion: We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via

  16. Extended lifespan, reduced body size and leg skeletal muscle mass, and decreased mitochondrial function in clk-1 transgenic mice.

    PubMed

    Takahashi, Kazuhide; Noda, Yoshihiro; Ohsawa, Ikuroh; Shirasawa, Takuji; Takahashi, Mayumi

    2014-10-01

    Mutational inactivation of clk-1, which encodes an enzyme necessary for the biosynthesis of coenzyme Q (CoQ), extends the lifespan of Caenorhabditis elegans. However, whether mammalian clk-1 regulates the lifespan of mice is not known because clk-1-deficiencies are embryonic lethal. Here, we investigated the lifespan of clk-1 transgenic mice (Tg96/I), which were rescued from embryonic lethality via the transgenic expression of mouse clk-1. Tg96/I mice lived longer and had smaller bodies than wild-type mice, but Tg96/I mice had CoQ levels equivalent to wild-type mice. The small-sized Tg96/I mice exhibited reduced whole-body oxygen consumption (VO2) during the dark period, and lean leg skeletal muscles with reduced mitochondrial VO2 and ATP content compared with wild-type mice. These findings indicate a close relationship between lifespan extension and decreased mitochondrial function, which was induced by the transgenic expression of clk-1, in leg skeletal muscles that exhibit high metabolic activity. PMID:25106098

  17. A natural antipredation experiment: predator control and reduced sea ice increases colony size in a long-lived duck.

    PubMed

    Hanssen, Sveinn A; Moe, Børge; Bårdsen, Bård-Jørgen; Hanssen, Frank; Gabrielsen, Geir W

    2013-09-01

    Anthropogenic impact on the environment and wildlife are multifaceted and far-reaching. On a smaller scale, controlling for predators has been increasing the yield from local natural prey resources. Globally, human-induced global warming is expected to impose severe negative effects on ecosystems, an effect that is expected to be even more pronounced in the scarcely populated northern latitudes. The clearest indication of a changing Arctic climate is an increase in both air and ocean temperatures leading to reduced sea ice distribution. Population viability is for long-lived species dependent on adult survival and recruitment. Predation is the main mortality cause in many bird populations, and egg predation is considered the main cause of reproductive failure in many birds. To assess the effect of predation and climate, we compared population time series from a natural experiment where a trapper/down collector has been licensed to actively protect breeding common eiders Somateria mollissima (a large seaduck) by shooting/chasing egg predators, with time series from another eider colony located within a nature reserve with no manipulation of egg predators. We found that actively limiting predator activity led to an increase in the population growth rate and carrying capacity with a factor of 3-4 compared to that found in the control population. We also found that population numbers were higher in years with reduced concentration of spring sea ice. We conclude that there was a large positive impact of human limitation of egg predators, and that this lead to higher population growth rate and a large increase in size of the breeding colony. We also report a positive effect of warming climate in the high arctic as reduced sea-ice concentrations was associated with higher numbers of breeding birds.

  18. Mesoscopic Modeling of Thrombus Formation and Growth: Platelet Deposition in Complex Geometries

    NASA Astrophysics Data System (ADS)

    Yazdani, Alireza; Karniadakis, George

    2014-11-01

    Haemodynamics and blood rheology are important contributing factors to thrombus formation at a vulnerable vessel wall, and adhesion of platelets to a vascular surface, particularly in regions of flow stagnation, recirculation and reattachment is significantly important in formation of thrombi. For example, haemodynamic micro-environment can have effects on thrombosis inside the atherosclerotic plaques and aneurysms. To study these effects, we have developed and validated a model for platelet aggregation in blood flow using Dissipative Particle Dynamics (DPD) method. In this model platelets are considered as single DPD particles interacting with each other via Morse potential once activated. We assign an activation delay time to each platelet such that they remain passive during that time. We investigate the effect of different geometries on platelet aggregation by considering arterial stenosis at different levels of occlusion, and aneurysms of different shapes and sizes. The results show a marked increase in platelet aggregation within the boundaries of deceleration zone by increasing the degree of stenosis. Further, we observe enhanced platelet margination and wall deposition in the presence of red blood cells.

  19. Left atrial thrombus formation after brief interruption of rivaroxaban.

    PubMed

    Turner, Matthew; Solarz, David

    2016-01-01

    Every year, nearly 250000 atrial fibrillation patients require temporary interruption of anticoagulation therapy for invasive procedures, acute illness, or bleeding events. Rivaroxaban is an oral anticoagulant that works by inhibiting factor Xa leading to a blockage of thrombin production, which inhibits platelet aggregation and thrombus formation. As with other anticoagulants, there is an increased risk of a thrombotic event occurring when rivaroxaban therapy is temporarily interrupted (TI) or prematurely discontinued. The 30-day rate of stroke or systemic embolism for rivaroxaban TI is 0.36%. Possible factors for higher than expected rates of embolic events include a prothrombotic perioperative environment among patients having TI for surgery and a prothrombotic environment associated with TI due to bleeding. The ROCKET AF study showed that there was no detectable difference in the risk of stroke and systemic embolism for participants treated with rivaroxaban vs warfarin undergoing TI. Another analysis suggested that the risk for stroke from TI is probably higher in the rivaroxaban group with 3 to 30 days discontinuation. Alternative anticoagulation therapy such as bridging should always be considered when stopping rivaroxaban.

  20. Chlorogenic Acid Inhibits Human Platelet Activation and Thrombus Formation

    PubMed Central

    Fuentes, Eduardo; Caballero, Julio; Alarcón, Marcelo; Rojas, Armando; Palomo, Iván

    2014-01-01

    Background Chlorogenic acid is a potent phenolic antioxidant. However, its effect on platelet aggregation, a critical factor in arterial thrombosis, remains unclear. Consequently, chlorogenic acid-action mechanisms in preventing platelet activation and thrombus formation were examined. Methods and Results Chlorogenic acid in a dose-dependent manner (0.1 to 1 mmol/L) inhibited platelet secretion and aggregation induced by ADP, collagen, arachidonic acid and TRAP-6, and diminished platelet firm adhesion/aggregation and platelet-leukocyte interactions under flow conditions. At these concentrations chlorogenic acid significantly decreased platelet inflammatory mediators (sP-selectin, sCD40L, CCL5 and IL-1β) and increased intraplatelet cAMP levels/PKA activation. Interestingly, SQ22536 (an adenylate cyclase inhibitor) and ZM241385 (a potent A2A receptor antagonist) attenuated the antiplatelet effect of chlorogenic acid. Chlorogenic acid is compatible to the active site of the adenosine A2A receptor as revealed through molecular modeling. In addition, chlorogenic acid had a significantly lower effect on mouse bleeding time when compared to the same dose of aspirin. Conclusions Antiplatelet and antithrombotic effects of chlorogenic acid are associated with the A2A receptor/adenylate cyclase/cAMP/PKA signaling pathway. PMID:24598787

  1. Reduced Fetal Cerebral Oxygen Consumption is Associated With Smaller Brain Size in Fetuses With Congenital Heart Disease

    PubMed Central

    Sun, Liqun; Macgowan, Christopher K; Sled, John G; Yoo, Shi-Joon; Manlhiot, Cedric; Porayette, Prashob; Grosse-Wortmann, Lars; Jaeggi, Edgar; McCrindle, Brian W; Kingdom, John; Hickey, Edward; Miller, Steven; Seed, Mike

    2015-01-01

    Background Fetal hypoxia has been implicated in the abnormal brain development seen in newborns with congenital heart disease (CHD). New magnetic resonance imaging (MRI) technology now offers the potential to investigate the relationship between fetal hemodynamics and brain dysmaturation. Methods and Results We measured fetal brain size, oxygen saturation and blood flow in the major vessels of the fetal circulation in 30 late gestation fetuses with CHD and 30 normal controls using phase contrast MRI and T2 mapping. Fetal hemodynamic parameters were calculated using a combination of MRI flow and oximetry data and fetal hemoglobin concentrations estimated from population averages. In fetuses with CHD, reductions in umbilical vein oxygen content (p<0.001), and failure of the normal streaming of oxygenated blood from the placenta to the ascending aorta were associated with a mean reduction in ascending aortic saturation of 10% (p < 0.001), while cerebral blood flow and cerebral oxygen extraction were no different from controls. This accounted for the mean 15% reduction in cerebral oxygen delivery (p = 0.08) and 32% reduction cerebral VO2 in CHD fetuses (p < 0.001), which were associated with a 13% reduction in fetal brain volume (p < 0.001). Fetal brain size correlated with ascending aortic oxygen saturation and cerebral VO2 (r = 0.37 p = 0.004). Conclusions This study supports a direct link between reduced cerebral oxygenation and impaired brain growth in fetuses with CHD and raises the possibility that in utero brain development could be improved with maternal oxygen therapy. PMID:25762062

  2. Flow residence time and regions of intraluminal thrombus deposition in intracranial aneurysms.

    PubMed

    Rayz, V L; Boussel, L; Ge, L; Leach, J R; Martin, A J; Lawton, M T; McCulloch, C; Saloner, D

    2010-10-01

    Thrombus formation in intracranial aneurysms, while sometimes stabilizing lesion growth, can present additional risk of thrombo-embolism. The role of hemodynamics in the progression of aneurysmal disease can be elucidated by patient-specific computational modeling. In our previous work, patient-specific computational fluid dynamics (CFD) models were constructed from MRI data for three patients who had fusiform basilar aneurysms that were thrombus-free and then proceeded to develop intraluminal thrombus. In this study, we investigated the effect of increased flow residence time (RT) by modeling passive scalar advection in the same aneurysmal geometries. Non-Newtonian pulsatile flow simulations were carried out in base-line geometries and a new postprocessing technique, referred to as "virtual ink" and based on the passive scalar distribution maps, was used to visualize the flow and estimate the flow RT. The virtual ink technique clearly depicted regions of flow separation. The flow RT at different locations adjacent to aneurysmal walls was calculated as the time the virtual ink scalar remained above a threshold value. The RT values obtained in different areas were then correlated with the location of intra-aneurysmal thrombus observed at a follow-up MR study. For each patient, the wall shear stress (WSS) distribution was also obtained from CFD simulations and correlated with thrombus location. The correlation analysis determined a significant relationship between regions where CFD predicted either an increased RT or low WSS and the regions where thrombus deposition was observed to occur in vivo. A model including both low WSS and increased RT predicted thrombus-prone regions significantly better than the models with RT or WSS alone. PMID:20499185

  3. Flow Residence Time and Regions of Intraluminal Thrombus Deposition in Intracranial Aneurysms

    PubMed Central

    Boussel, L.; Ge, L.; Leach, J. R.; Martin, A. J.; Lawton, M. T.; McCulloch, C.; Saloner, D.

    2010-01-01

    Thrombus formation in intracranial aneurysms, while sometimes stabilizing lesion growth, can present additional risk of thrombo-embolism. The role of hemodynamics in the progression of aneurysmal disease can be elucidated by patient-specific computational modeling. In our previous work, patient-specific computational fluid dynamics (CFD) models were constructed from MRI data for three patients who had fusiform basilar aneurysms that were thrombus-free and then proceeded to develop intraluminal thrombus. In this study, we investigated the effect of increased flow residence time (RT) by modeling passive scalar advection in the same aneurysmal geometries. Non-Newtonian pulsatile flow simulations were carried out in base-line geometries and a new postprocessing technique, referred to as “virtual ink” and based on the passive scalar distribution maps, was used to visualize the flow and estimate the flow RT. The virtual ink technique clearly depicted regions of flow separation. The flow RT at different locations adjacent to aneurysmal walls was calculated as the time the virtual ink scalar remained above a threshold value. The RT values obtained in different areas were then correlated with the location of intra-aneurysmal thrombus observed at a follow-up MR study. For each patient, the wall shear stress (WSS) distribution was also obtained from CFD simulations and correlated with thrombus location. The correlation analysis determined a significant relationship between regions where CFD predicted either an increased RT or low WSS and the regions where thrombus deposition was observed to occur in vivo. A model including both low WSS and increased RT predicted thrombus-prone regions significantly better than the models with RT or WSS alone. PMID:20499185

  4. ST-Elevation Myocardial Infarction, Thrombus Aspiration, and Different Invasive Strategies. A TASTE Trial Substudy

    PubMed Central

    Fröbert, Ole; Calais, Fredrik; James, Stefan K; Lagerqvist, Bo

    2015-01-01

    Background The clinical effect of thrombus aspiration in ST-elevation myocardial infarction may depend on the type of aspiration catheter and stenting technique. Methods and Results The multicenter, prospective, randomized, open-label trial Thrombus Aspiration in ST-Elevation myocardial infarction in Scandinavia (TASTE) did not demonstrate a clinical benefit of thrombus aspiration compared to percutaneous coronary intervention alone. We assessed the effect of type of aspiration device, stent type, direct stenting, and postdilatation on outcomes at 1 year. There was no difference in all-cause mortality, between the 3 most frequently used aspiration catheters (Eliminate [Terumo] 5.4%, Export [Medtronic] 5.0%, Pronto [Vascular Solutions] 4.5%) in patients randomized to thrombus aspiration. There was no difference in mortality between directly stented patients randomized to thrombus aspiration compared to patients randomized to percutaneous coronary intervention only (risk ratio 1.08, 95% CI 0.70 to 1.67, P=0.73). Similarly, there was no difference in mortality between the 2 randomized groups for patients receiving drug-eluting stents (risk ratio 0.89, 95% CI 0.63 to 1.26, P=0.50) or for those treated with postdilation (risk ratio 0.72, 95% CI 0.49 to 1.07, P=0.11). Furthermore, there was no difference in rehospitalization for myocardial infarction or stent thrombosis between the randomized arms in any of the subgroups. Conclusions In patients with ST-elevation myocardial infarction randomized to thrombus aspiration, the type of aspiration catheter did not affect outcome. Stent type, direct stenting, or postdilation did not affect outcome irrespective of treatment with thrombus aspiration and percutaneous coronary intervention or percutaneous coronary intervention alone. Clinical Trial Registration URL: ClinicalTrials.gov. Unique identifier: NCT01093404, https://clinicaltrials.gov/ct2/show/NCT01093404. PMID:26077585

  5. Contrast-Enhanced Anatomic Imaging as Compared to Contrast-Enhanced Tissue Characterization for Detection of Left Ventricular Thrombus

    PubMed Central

    Weinsaft, Jonathan W.; Kim, Raymond J.; Ross, Michael; Krauser, Daniel; Manoushagian, Shant; LaBounty, Troy M.; Cham, Matthew D.; Min, James K.; Healy, Kirsten; Wang, Yi; Parker, Michele; Roman, Mary J.; Devereux, Richard B.

    2016-01-01

    Objectives To compare contrast-enhanced anatomic imaging to contrast-enhanced tissue characterization (DE-CMR) for left ventricular (LV) thrombus detection. Background Contrast echocardiography (echo) detects LV thrombus based on anatomic appearance whereas delayed-enhancement cardiac magnetic resonance (DE-CMR) imaging detects thrombus based on tissue characteristics. DE-CMR has been validated as an accurate technique for thrombus but its utility compared to contrast echo is unknown. Methods Multimodality imaging was performed in 121 patients at high-risk for thrombus due to myocardial infarction or heart failure. Imaging included three anatomic imaging techniques for thrombus detection (contrast echo, non-contrast echo, cine-CMR) and a reference of DE-CMR tissue characterization. LV structural parameters were quantified to identify markers for thrombus and predictors of additive utility of contrast-enhanced thrombus imaging. Results 24 patients had thrombus by DE-CMR. Patients with thrombus had larger infarcts (by DE-CMR), more aneurysms and lower LVEF (by CMR and echo) than those without thrombus. Contrast echo nearly doubled sensitivity (61% vs. 33%, p<0.05) and yielded improved accuracy (92% vs. 82%, p<0.01) vs. non-contrast echo. Patients who derived incremental diagnostic utility from DE-CMR had lower LVEF vs. those in whom non-contrast echo alone accurately assessed thrombus (35±9% vs. 42±14%, p<0.01), with a similar trend for patients that derived incremental benefit from contrast echo (p=0.08). Contrast echo and cine-CMR closely agreed on the diagnosis of thrombus (kappa=0.79, p<0.001). Thrombus prevalence was lower by contrast echo than DE-CMR (p<0.05). Thrombus detected by DE-CMR but not by contrast echo was more likely to be mural in shape or, when apical, small in volume (p<0.05). Conclusions Echo contrast in high-risk patients markedly improves detection of LV thrombus, but does not detect a substantial number of thrombi identified by DE-CMR tissue

  6. Effectiveness of a Comprehensive Stress Management Program to Reduce Work-Related Stress in a Medium-Sized Enterprise

    PubMed Central

    2014-01-01

    Objectives To assess the effectiveness of a comprehensive workplace stress management program consisting of participatory action-oriented training (PAOT) and individual management. Methods A comprehensive workplace stress management program was conducted in a medium-sized enterprise. The baseline survey was conducted in September 2011, using the Korean Occupational Stress Scale (KOSS) and Worker’s Stress Response Inventory (WSRI). After implementing both organizational and individual level interventions, the follow up evaluation was conducted in November 2011. Results Most of the workers participated in the organizational level PAOT and made Team-based improvement plans. Based on the stress survey, 24 workers were interviewed by a researcher. After the organizational and individual level interventions, there was a reduction of several adverse psychosocial factors and stress responses. In the case of blue-collar workers, psychosocial factors such as the physical environment, job demands, organizational system, lack of rewards, and occupational climate were significantly improved; in the case of white-collar workers, the occupational climate was improved. Conclusions In light of these results, we concluded that the comprehensive stress management program was effective in reducing work-related stress in a short-term period. A persistent long-term follow up is necessary to determine whether the observed effects are maintained over time. Both team-based improvement activities and individual interviews have to be sustainable and complementary to each other under the long-term plan. PMID:24524591

  7. A Self-Organizing Map-Based Approach to Generating Reduced-Size, Statistically Similar Climate Datasets

    NASA Astrophysics Data System (ADS)

    Cabell, R.; Delle Monache, L.; Alessandrini, S.; Rodriguez, L.

    2015-12-01

    Climate-based studies require large amounts of data in order to produce accurate and reliable results. Many of these studies have used 30-plus year data sets in order to produce stable and high-quality results, and as a result, many such data sets are available, generally in the form of global reanalyses. While the analysis of these data lead to high-fidelity results, its processing can be very computationally expensive. This computational burden prevents the utilization of these data sets for certain applications, e.g., when rapid response is needed in crisis management and disaster planning scenarios resulting from release of toxic material in the atmosphere. We have developed a methodology to reduce large climate datasets to more manageable sizes while retaining statistically similar results when used to produce ensembles of possible outcomes. We do this by employing a Self-Organizing Map (SOM) algorithm to analyze general patterns of meteorological fields over a regional domain of interest to produce a small set of "typical days" with which to generate the model ensemble. The SOM algorithm takes as input a set of vectors and generates a 2D map of representative vectors deemed most similar to the input set and to each other. Input predictors are selected that are correlated with the model output, which in our case is an Atmospheric Transport and Dispersion (T&D) model that is highly dependent on surface winds and boundary layer depth. To choose a subset of "typical days," each input day is assigned to its closest SOM map node vector and then ranked by distance. Each node vector is treated as a distribution and days are sampled from them by percentile. Using a 30-node SOM, with sampling every 20th percentile, we have been able to reduce 30 years of the Climate Forecast System Reanalysis (CFSR) data for the month of October to 150 "typical days." To estimate the skill of this approach, the "Measure of Effectiveness" (MOE) metric is used to compare area and overlap

  8. Long-term clinical outcomes of the left ventricular thrombus in patients with ST elevation anterior myocardial infarction

    PubMed Central

    Ebrahimi, Mahmoud; Fazlinezhad, Afsoon; Alvandi-Azari, Masoomeh; Abdar Esfahani, Morteza

    2015-01-01

    BACKGROUND This study was performed to determine the size of left ventricular thrombus (LVT), risk of systemic embolization and response to medical treatment during 18 months of follow up in the patients with anterior-ST elevation myocardial infarction (aSTEMI). METHODS This cross-sectional study was performed on thirty-five patients with anterior myocardial infarction (MI), in Emam Reza Hospital and Ghaem Hospital, Mashhad, Iran, from August 2008 to January 2011. Warfarin was prescribed for all the patients. Transthoracic echocardiographic study was performed on the 1st, 2nd, 4th, 6th, 12th and 18th months. Outcomes included rate of death, MI, stroke, systemic embolization, major bleeding and change in thrombus size following treatment. RESULTS The resolve rate of clot on the 2nd, 4th, 6th, 12th and 18th months was 64.7, 86.6, 81.4, 81.4 and 100 percent, respectively. In five patients with complete clot resolution, clot reformation occurred after warfarin discontinuation. In these patients, left ventricular ejection fraction (LVEF) improvement was poor. During the study period, five patients died due to severe heart failure. One patient developed hematuria whereas non-experienced thromboembolic events. The mean LVEF at study initiation was 30.8 ± 0.92%, which improved to 42 ± 0.84% (P < 0.05) at the end. CONCLUSION All LVT was resolved with a combination therapy of antiplatelet and warfarin without any thromboembolic event. In patients with a poor improvement in the LV function, due to the risk of LVT reformation, lifelong warfarin therapy was recommended. PMID:26089924

  9. Thrombus Formation After Percutaneous Catheterization and Manual Compression of the Femoral Artery in Heparinized Sheep

    SciTech Connect

    Kim, Young Hwan; Pavcnik, Dusan Kakizawa, Hideyaki; Uchida, Barry T.; Burke, Allen; Loriaux, Marc; Keller, Frederick S.; Rosch, Josef

    2010-04-15

    The purpose of this study was to evaluate the angiographic and histopathologic changes in the superficial femoral artery (SFA) in heparinized sheep shortly after catheterization with an 8-Fr sheath and manual compression hemostasis either with standard manual compression (SMC) or with the use of a procoagulant chitosan-based HemCon Bandage. The evaluation was done in 38 SFAs of 19 heparinized (100 mg/kg) sheep. After a 5-min catheterization with an 8-Fr sheath, a 5-min compression was applied. Follow-up angiograms to evaluate hemostasis were done immediately after release of compression and then at 2.5-min intervals until no extravasation was present. Compression was reapplied between angiograms. Final angiograms were performed approximately 30 min after hemostasis and after 3 min of passive flexion and extension of sheep hind limbs. Sheep were then euthanized and SFA specimens with surrounding tissues excised for histopathologic evaluation. Both types of compression caused similar changes in the catheterized SFAs. Follow-up angiograms showed mild arterial narrowing in 14 SFAs and intraluminal clots in 9 SFAs. Histology revealed periarterial hematoma in all 38 specimens. Intraluminal thrombi consisting predominantly of platelets and fibrin were present in 32 SFAs. Their size varied from superficial elevations (8 arteries) to medium-sized, 1- to 2-mm, polypoid protrusions (15 arteries) to large polypoid clots, 3-4 mm long (9 arteries). In six SFAs, the arterial access sites were not included in the obtained specimens. In conclusion, hemostasis with manual compression is achieved in the acute phase by formation of a predominantly platelet-fibrin thrombus occluding the arterial wall access site and often extending significantly into the arterial lumen. The healing process of arterial access sites should be explored several days after catheterization.

  10. Nevada's Class-Size Reduction Program. Nevada Revised Statutes 388.700-388.730: "Program To Reduce the Pupil-Teacher Ratio." Background Paper 97-7.

    ERIC Educational Resources Information Center

    Sturm, H. Pepper

    In 1989, the Nevada Legislature enacted the Class-Size Reduction (CSR) Act. The measure was designed to reduce the pupil-teacher ratio in the public schools, particularly in the earliest grades. The program was scheduled to proceed in several phases. The first step reduced the student-teacher ratio in selected kindergartens and first grade classes…

  11. Segmentation of the thrombus of giant intracranial aneurysms from CT angiography scans with lattice Boltzmann method.

    PubMed

    Chen, Yu; Navarro, Laurent; Wang, Yan; Courbebaisse, Guy

    2014-01-01

    Computed Tomography Angiography (CTA) plays an essential role in the diagnosis, treatment evaluation, and monitoring of cerebral aneurysms. Segmentation of CTA medical images of giant intracranial aneurysms (GIA) provides quantitative measurements of thrombus and aneurysms geometrical characteristics allowing 3D reconstruction. In fact, GIA demonstrated neuroradiological features and propensity of partial or total spontaneous intra-aneurysmal thrombosis generating a thrombus. Despite intensive researches on medical image segmentation, aneurysm (Lumen, Thrombus, and Parent Blood Vessels) segmentation remains as a difficult problem that has not been yet resolved. In this paper, we proposed a Lattice Boltzmann Geodesic Active Contour Method (LBGM) for aneurysm segmentation in CTA images in order to estimate both the volumes of the thrombus and the aneurysm. Although the noise in the CTA images is very strong and the edges of the thrombus are not so different than the surrounding tissues, the aneurysms are segmented effectively. Based on these results, a method using a dome-neck aspect ratio (AR) parameter for the evaluation of the Spontaneous Thrombosis (ST) phenomena demonstrates the promising potentiality of this LBGM for clinical applications. PMID:24077409

  12. Common Carotid Artery Stump Syndrome Due to Mobile Thrombus Detected by Carotid Duplex Ultrasonography.

    PubMed

    Omoto, Shusaku; Hasegawa, Yuki; Sakai, Kenichiro; Matsuno, Hiromasa; Arai, Ayumi; Terasawa, Yuka; Mitsumura, Hidetaka; Iguchi, Yasuyuki

    2016-10-01

    Carotid stump syndrome is a cause of recurrent embolic stroke following occlusion of the ipsilateral internal carotid artery. The present report describes a case of recurrent cerebral embolism ipsilateral to a chronically occluded left common carotid artery (CCA), i.e., "CCA stump syndrome." Doppler color flow imaging showed anterograde flow in the left internal and external carotid arteries, which were supplied by collateral flow from the superior thyroid artery inflowing just proximal to the left carotid bifurcation. According to carotid duplex ultrasonography (CDU), a low-echoic mobile thrombus was noted at the distal stump of the occluded CCA, which presumably caused distal embolism. The low-echoic mobile thrombus dramatically changed to a homogenously high-echoic thrombus, and there was no recurrence of stroke after antiplatelet and anticoagulant therapy. This is the first report to demonstrate a CDU-verified temporal change in the thrombus at the stump in CCA stump syndrome. CDU is a noninvasive and useful technique to characterize hemodynamics, thrombus morphology, and the response to therapy. PMID:27567297

  13. Endobrevin/VAMP-8–dependent dense granule release mediates thrombus formation in vivo

    PubMed Central

    Graham, Gwenda J.; Ren, Qiansheng; Dilks, James R.; Blair, Price; Flaumenhaft, Robert

    2009-01-01

    Individuals whose platelets lack dense or α-granules suffer various degrees of abnormal bleeding, implying that granule cargo contributes to hemostasis. Despite these clinical observations, little is known regarding the effects of impaired platelet granule secretion on thrombus formation in vivo. In platelets, SNARE proteins mediate the membrane fusion events required for granule cargo release. Endobrevin/VAMP-8 is the primary vesicle-SNARE (v-SNARE) responsible for efficient release of dense and α-granule contents; thus, VAMP-8−/− mice are a useful model to evaluate the importance of platelet granule secretion in thrombus formation. Thrombus formation, after laser-induced vascular injury, in these mice is delayed and decreased, but not absent. In contrast, thrombus formation is almost completely abolished in the mouse model of Hermansky-Pudlak syndrome, ruby-eye, which lacks dense granules. Evaluation of aggregation of VAMP-8−/− and ruby-eye platelets indicates that defective ADP release is the primary abnormality leading to impaired aggregation. These results demonstrate the importance of dense granule release even in the earliest phases of thrombus formation and validate the distal platelet secretory machinery as a potential target for antiplatelet therapies. PMID:19395672

  14. Endobrevin/VAMP-8-dependent dense granule release mediates thrombus formation in vivo.

    PubMed

    Graham, Gwenda J; Ren, Qiansheng; Dilks, James R; Blair, Price; Whiteheart, Sidney W; Flaumenhaft, Robert

    2009-07-30

    Individuals whose platelets lack dense or alpha-granules suffer various degrees of abnormal bleeding, implying that granule cargo contributes to hemostasis. Despite these clinical observations, little is known regarding the effects of impaired platelet granule secretion on thrombus formation in vivo. In platelets, SNARE proteins mediate the membrane fusion events required for granule cargo release. Endobrevin/VAMP-8 is the primary vesicle-SNARE (v-SNARE) responsible for efficient release of dense and alpha-granule contents; thus, VAMP-8(-/-) mice are a useful model to evaluate the importance of platelet granule secretion in thrombus formation. Thrombus formation, after laser-induced vascular injury, in these mice is delayed and decreased, but not absent. In contrast, thrombus formation is almost completely abolished in the mouse model of Hermansky-Pudlak syndrome, ruby-eye, which lacks dense granules. Evaluation of aggregation of VAMP-8(-/-) and ruby-eye platelets indicates that defective ADP release is the primary abnormality leading to impaired aggregation. These results demonstrate the importance of dense granule release even in the earliest phases of thrombus formation and validate the distal platelet secretory machinery as a potential target for antiplatelet therapies.

  15. Intrameal Hepatic Portal and Intraperitoneal Infusions of Glucagon-Like Peptide-1 Reduce Spontaneous Meal Size in the Rat via Different Mechanisms

    PubMed Central

    Rüttimann, Elisabeth B.; Arnold, Myrtha; Hillebrand, Jacquelien J.; Geary, Nori; Langhans, Wolfgang

    2009-01-01

    Peripheral administration of glucagon-like peptide (GLP)-1 reduces food intake in animals and humans, but the sites and mechanism of this effect and its physiological significance are not yet clear. To investigate these issues, we prepared rats with chronic catheters and infused GLP-1 (0.2 ml/min; 2.5 or 5.0 min) during the first spontaneous dark-phase meals. Infusions were remotely triggered 2–3 min after meal onset. Hepatic portal vein (HPV) infusion of 1.0 or 3.0 (but not 0.33) nmol/kg GLP-1 reduced the size of the ongoing meal compared with vehicle without affecting the subsequent intermeal interval, the size of subsequent meals, or cumulative food intake. In double-cannulated rats, HPV and vena cava infusions of 1.0 nmol/kg GLP-1 reduced meal size similarly. HPV GLP-1 infusions of 1.0 nmol/kg GLP-1 also reduced meal size similarly in rats with subdiaphragmatic vagal deafferentations and in sham-operated rats. Finally, HPV and ip infusions of 10 nmol/kg GLP-1 reduced meal size similarly in sham-operated rats, but only HPV GLP-1 reduced meal size in subdiaphragmatic vagal deafferentation rats. These data indicate that peripherally infused GLP-1 acutely and specifically reduces the size of ongoing meals in rats and that the satiating effect of ip, but not iv, GLP-1 requires vagal afferent signaling. The findings suggest that iv GLP-1 infusions do not inhibit eating via hepatic portal or hepatic GLP-1 receptors but may act directly on the brain. PMID:18948395

  16. Allocating Sample Sizes to Reduce Budget for Fixed-Effect 2×2 Heterogeneous Analysis of Variance

    ERIC Educational Resources Information Center

    Luh, Wei-Ming; Guo, Jiin-Huarng

    2016-01-01

    This article discusses the sample size requirements for the interaction, row, and column effects, respectively, by forming a linear contrast for a 2×2 factorial design for fixed-effects heterogeneous analysis of variance. The proposed method uses the Welch t test and its corresponding degrees of freedom to calculate the final sample size in a…

  17. Placental restriction of fetal growth reduces size at birth and alters postnatal growth, feeding activity, and adiposity in the young lamb.

    PubMed

    De Blasio, Miles J; Gatford, Kathryn L; Robinson, Jeffrey S; Owens, Julie A

    2007-02-01

    Intrauterine growth restriction (IUGR) is associated with accelerated growth after birth. Together, IUGR and accelerated growth after birth predict reduced lean tissue mass and increased obesity in later life. Although placental insufficiency is a major cause of IUGR, whether it alters growth and adiposity in early postnatal life is not known. We hypothesized that placental restriction (PR) in the sheep would reduce size at birth and increase postnatal growth rate, fat mass, and feeding activity in the young lamb. PR reduced survival rate and size at birth, with soft tissues reduced to a greater extent than skeletal tissues and relative sparing of head width (P < 0.05 for all). PR did not alter absolute growth rates (i.e., the slope of the line of best fit for age vs. parameter size from birth to 45 days of age) but increased neonatal fractional growth rates (absolute growth rate relative to size at birth) for body weight (+24%), tibia (+15%) and metatarsal (+18%) lengths, hindlimb (+23%) and abdominal (+19%) circumferences, and fractional growth rates for current weight (P < 0.05) weekly throughout the first 45 days of life. PR and small size at birth reduced individual skeletal muscle weights and increased visceral adiposity in absolute and relative terms. PR also altered feeding activity, which increased with decreasing size at birth and was predictive of increased postnatal growth and adiposity. In conclusion, PR reduced size at birth and induced catch-up growth postnatally, normalizing weight and length but increasing adiposity in early postnatal life. Increased feeding activity may contribute to these alterations in growth and body composition following prenatal restraint and, if they persist, may lead to adverse metabolic and cardiovascular outcomes in later life. PMID:17023666

  18. Unusual Case of Parkes Weber Syndrome with Aneurysm of the Left Common Iliac Vein and Thrombus in Inferior Vena Cava.

    PubMed

    Banzic, Igor; Brankovic, Milos; Koncar, Igor; Ilic, Nikola; Davidovic, Lazar

    2015-10-01

    We report an unusual case of aneurysm of the left common iliac vein and thrombus formation in inferior vena cava associated with Parkes Weber syndrome (PWS). In addition to many already known clinical signs which determine PWS, common iliac vein aneurysm formation together with inferior vena cava thrombus present a new clinical feature and new challenges in treatment strategy of these patients. PMID:26122423

  19. Severe reversible dilated cardiomyopathy associated with a large left ventricular thrombus in a young child with middle aortic syndrome.

    PubMed

    Ponniah, U; Overholt, E

    2014-01-01

    We report a case of a seven-year girl who presented with severe dilated cardiomyopathy (DCM) associated with a large thrombus in the left ventricle (LV). She had a long segment stenosis of the lower thoracic descending aorta, possibly due to non-specific aortitis and underwent successful stent angioplasty. The LV thrombus resolved after heparin without sequelae.

  20. Severe reversible dilated cardiomyopathy associated with a large left ventricular thrombus in a young child with middle aortic syndrome

    PubMed Central

    Overholt, E

    2014-01-01

    We report a case of a seven-year girl who presented with severe dilated cardiomyopathy (DCM) associated with a large thrombus in the left ventricle (LV). She had a long segment stenosis of the lower thoracic descending aorta, possibly due to non-specific aortitis and underwent successful stent angioplasty. The LV thrombus resolved after heparin without sequelae. PMID:26236372

  1. The prevention of circulatory collapse in left atrial myxoma or left atrail thrombus patients.

    PubMed

    Sun, Jie; Ding, Zhengnian

    2016-05-01

    Some patients with myxoma or thrombus may develop to severe hypotension or sudden death. In this article, we hypothesize a clinical scenario that when the myxoma or thrombus blocks in the mitral valve and causes significant hypotension during anesthesia or surgery. Increasing cardiac preload will be an effective preventive method to increasing the mitral valve annulus and decreasing the severity of stenosis, as a result it will prevent circulatory collapse. Our hypothesis will decrease the possibility of lethal mitral valve stenosis induced by left atrial mass blocking the mitral valve area. In addition, we should also maintain a relative slow heart rate and a relative high systemic vascular resistance. PMID:27063074

  2. Thrombus on Indwelling Central Venous Catheters: The Histopathology of 'Fibrin Sheaths'

    SciTech Connect

    Suojanen, James Norman; Brophy, David Paul; Nasser, Imad

    2000-03-15

    Purpose: Central venous catheters (CVC) may fail for many reasons, though 'fibrin sheaths' blocking catheter ports are usually implicated. We examined the sheaths removed from dialysis catheters to determine their histopathology.Methods: Ten catheter strippings were performed and the removed material was studied grossly and microscopically.Results: The histologic specimens showed thrombus both with and without a proteinaceous sheath.Conclusion: Dialysis catheters fail because of thrombus formation. This can occur in either the absence or presence of a protein coating on the catheter, the so-called 'fibrin sheath.'.

  3. Jugular thrombophlebitis in horses: A review of fibrinolysis, thrombus formation, and clinical management

    PubMed Central

    Dias, Deborah Penteado Martins; de Lacerda Neto, José Corrêa

    2013-01-01

    Thrombophlebitis of the jugular vein is commonly observed in horses, particularly during intensive care, and leads to local and systemic inflammatory responses as well as head and neck circulatory impairment. Thrombolytic therapy is widely used in human practice with the aim of thrombus dissolution and recanalization of the injured vessels. There are similarities between human and horse coagulation and fibrinolytic processes. This review examines the fibrinolytic system, thrombus formation, and the clinical management of jugular thrombophlebitis, including thrombolytic therapy. There is evidence that early regional thrombolytic therapy for jugular thrombophlebitis in horses may be effective to achieve sustained recanalization. PMID:23814304

  4. Primary Synovial Sarcoma of the Kidney with Inferior Vena Caval Thrombus.

    PubMed

    Chandrasekaran, Deepak; Narayanaswamy, Kathiresan; Sundersingh, Shirley; Senniappan, Karthikeyan; Raja, Anand

    2016-09-01

    Synovial sarcomas occurs primarily in the soft tissues, mostly in para-articular regions of the extremities. These tumors have been described in other unusual locations like the pleura, lungs, mediastinum, and kidneys. Primary synovial sarcoma of the kidney is a recently described entity; to date, a total of approximately 35 cases have been reported. Only three cases of primary synovial sarcoma of kidney with IVC thrombus have been reported so far. Here we present the case of a 44 year old gentleman, with primary synovial sarcoma of the left kidney with caval thrombus. PMID:27651698

  5. Acute Bilateral Internal Carotid Occlusion from Embolization of Left Atrial Thrombus During Transesophageal Echocardiography: Case Report

    PubMed Central

    Mahmood, Syed Saad; Manjila, Sunil; Singh, Gagandeep; Xavier, Andrew R

    2016-01-01

    Background and purpose: Transesophageal echocardiography (TEE) is a relatively safe imaging modality used to visualize intracardiac thrombus. Summary of case: We report on a unique, fatal complication during TEE of embolization of a pre-existing “smoking” left atrial thrombus causing acute bilateral internal carotid occlusion, confirmed on angiogram. Conclusions: Patients with history of lung pathology, such as COPD, who experience retching and cough during transesophageal echocardiography may be more susceptible to embolization of pre-existing thrombi. A need exists to risk stratify such patients. PMID:27403219

  6. Involvement of the Mural Thrombus as a Site of Protease Release and Activation in Human Aortic Aneurysms

    PubMed Central

    Fontaine, Vincent; Jacob, Marie-Paule; Houard, Xavier; Rossignol, Patrick; Plissonnier, Didier; Angles-Cano, Eduardo; Michel, Jean-Baptiste

    2002-01-01

    Acquired abdominal aortic aneurysms are usually associated with a mural thrombus through which blood continues to flow. Some early data suggest that aneurysmal evolution correlates with the biological activity of the thrombus. Our hypothesis was therefore that the thrombus could adsorb blood components and store, release, and participate in the activation of proteases involved in aneurysmal evolution. For this purpose, we have explored both the metalloproteinase and fibrinolytic systems in the thrombus and the wall of human aneurysms. We have first investigated blood clot formation and lysis in vitro. Spontaneous clotting induces a release of promatrix metalloproteinase (pro-MMP)-9 into the serum that was fourfold higher than in paired control plasma (P < 0.001). Fibrinolysis progressively released more MMP-9 in a time-dependent manner (P < 0.01). After selective isolation, we demonstrated that polymorphonuclear leukocytes are the main source of MMP-9 release during clot formation. Protease content was then analyzed in 35 mural thrombi and walls of human abdominal aortic aneurysms sampled during surgical repair. In 15 aneurysms, the liquid phase at the interface between the thrombus and the wall was sampled separately. Both thrombus and wall contained MMP-2 and MMP-9 but the ratio MMP-9/MMP-2 was higher in the thrombus than in the wall. The liquid interface also contained active MMP-9. Immunohistochemistry of the thrombus confirmed these findings, showing the presence of polymorphonuclear leukocytes at the luminal pole of the thrombus, co-localizing with MMP-9 storage. In contrast, MMP-3 and MMP-7 were only present in the aneurysmal wall. Plasminogen was present in the mural thrombus but plasmin activity was present in both thrombus and wall. In the liquid interface, plasmin-α2-anti-plasmin complexes were detected demonstrating in vivo the activation of plasminogen. In contrast, u-PA and t-PA were detectable only in the wall, suggesting that plasminogen present in

  7. Multimodality Treatment for Hepatocellular Carcinoma With Portal Vein Tumor Thrombus

    PubMed Central

    Wang, Kang; Guo, Wei Xing; Chen, Min Shan; Mao, Yi Lei; Sun, Bei Cheng; Shi, Jie; Zhang, Yao Jun; Meng, Yan; Yang, Ye Fa; Cong, Wen Ming; Wu, Meng Chao; Lau, Wan Yee; Cheng, Shu Qun

    2016-01-01

    Abstract The optimal treatment for hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) remains controversial. We aimed to investigate the best treatment for patients with HCC with PVTT. From January 2002 to January 2014, the data from all consecutive patients with HCC with PVTT who underwent surgical treatment (ST),TACE,TACE combined with sorafenib (TACE-Sor), or TACE combined with radiotherapy (TACE-RT) in the 4 largest tertiary hospitals in China were analyzed retrospectively. The patients were divided into 3 subtypes according to the extent of PVTT in the portal vein (type I-III). The primary endpoint was overall survival (OS). A total of 1580 patients with HCC with PVTT were included in the study. The median survival times (MST) for ST (n = 745) for type I, II, and III patients (95% CI) were 15.9 (13.3–18.5), 12.5 (10.7–14.3), and 6.0 (4.3–7.7) months, respectively. The corresponding figures for patients after TACE (n = 604) were 9.3 (5.6–12.9), 4.9 (4.1–5.7), and 4.0 (3.1–4.9), respectively; for patients after TACE-Sor (n = 113) 12.0 (6.6–17.4), 8.9 (6.7–11.1), and 7.0 (3.0–10.9), respectively; and for patients after TACE-RT (n = 118) 12.2 (0–24.7), 10.6 (6.8–14.5), and 8.9 (5.2–12.6), respectively. Comparison among the different treatments for the 3 subtypes of PVTT patients after propensity score (PS) matching showed the effectiveness of ST to be the best for type I and type II PVTT patients, and TACE-RT was most beneficial for type III patients. Treatment was an independent risk factor of OS. ST was the best treatment for type I and II PVTT patients with Child-Pugh A and selected B liver function. TACE-RT should be given to type III PVTT patients. PMID:26986115

  8. Spontaneous echo contrast masking thrombus in giant left atrium of mitral stenosis-a dilemma in clinical diagnosis

    PubMed Central

    Islam, AKM Monwarul; Salam, Md. Abdus; Sayeed, Md. Zahidus; Kibria, Md. Golam

    2015-01-01

    Spontaneous echo contrast (SEC) and thrombus in enlarged left atrium (LA) are common in mitral valvular disease (MVD) and SEC is considered to be a prethrombotic condition. Reliable exclusion of LA thrombus is important before any definitive curative attempts like percutaneous transluminal mitral commissurotomy (PTMC), closed mitral commissurotomy (CMC) or innovative therapies like pulmonary vein isolation and percutaneous closure of the LA appendage. Echocardiography, particularly the transesophageal echocardiography (TEE) is considered to be the gold standard for the diagnosis and to exclude LA thrombus. However, LA thrombus may remain rarely undetected even by TEE potentially making the interventions a risky job. We present a case of mitral stenosis (MS) with giant LA where profuse, dense SEC masked the underlying thrombus in the LA cavity. PMID:26649032

  9. Incremental Value of Three-Dimensional Transesophageal Echocardiography over the Two-Dimensional Technique in the Assessment of a Thrombus in Transit through a Patent Foramen Ovale.

    PubMed

    Thind, Munveer; Ahmed, Mustafa I; Gok, Gulay; Joson, Marisa; Elsayed, Mahmoud; Tuck, Benjamin C; Townsley, Matthew M; Klas, Berthold; McGiffin, David C; Nanda, Navin C

    2015-05-01

    We report a case of a right atrial thrombus traversing a patent foramen ovale into the left atrium, where three-dimensional transesophageal echocardiography provided considerable incremental value over two-dimensional transesophageal echocardiography in its assessment. As well as allowing us to better spatially characterize the thrombus, three-dimensional transesophageal echocardiography provided a more quantitative assessment through estimation of total thrombus burden.

  10. Applicability of colloid filtration theory in size-distributed, reduced porosity, granular media in the absence of energy barriers.

    PubMed

    Pazmino, Eddy F; Ma, Huilian; Johnson, William P

    2011-12-15

    The vast majority of colloid transport experiments use granular porous media with narrow size distribution to facilitate comparison with colloid filtration theory, which represents porous media with a single collector size. In this work we examine retention of colloids ranging in size from 0.21 to 9.1 μm in diameter, in columns packed with uniform and size-distributed borosilicate glass bead porous media with porosity ranging from 0.38 to 0.28. Conditions were favorable to attachment (absent a significant energy barrier). The goal was to determine the applicability of colloid filtration theory to colloid retention in these media. We also directly observed deposition at the pore scale in packed flow cells. The pore domain was characterized via high resolution computerized X-ray micro tomography (HRXMT). The flow field was examined using Lattice-Boltzmann flow simulation methods (LBM). The influence of preferential flow paths on colloid retention in the lowest porosity media was accounted for by correcting the fluid velocity. Straining in pore throats too small to pass was not a significant contributor to colloid retention despite colloid-to-collector size ratios up to 0.05. Mechanistic simulations via the Ma-Pedel-Fife-Johnson correlation equation (MPFJ) for colloid filtration predicted the experimentally observed trends in deposition with porosity when a number-based mean grain size was used.

  11. The insulin-like growth factor 1 receptor (IGF1R) contributes to reduced size in dogs

    PubMed Central

    Hoopes, Barbara C.; Rimbault, Maud; Liebers, David; Ostrander, Elaine A.

    2012-01-01

    Domestic dog breeds have undergone intense selection for a variety of morphologic features, including size. Among small-dog breeds, defined as those averaging less than ~15 in. at the withers, there remains still considerable variation in body size. Yet essentially all such dogs are fixed for the same allele at the insulin-like growth factor 1 gene, which we and others previously found to be a size locus of large effect. In this study we sought to identify additional genes that contribute to tiny size in dogs using an association scan with the single nucleotide polymorphism (SNP) dataset CanMap, in which 915 purebred dogs were genotyped at 60,968 SNP markers. Our strongest association for tiny size (defined as breed-average height not more than 10 in. at the withers) was on canine chromosome 3 (p = 1.9 × 10−70). Fine mapping revealed a nonsynonymous SNP at chr3:44,706,389 that changes a highly conserved arginine at amino acid 204 to histidine in the insulin-like growth factor 1 receptor (IGF1R). This mutation is predicted to prevent formation of several hydrogen bonds within the cysteine-rich domain of the receptor’s ligand-binding extracellular subunit. Nine of 13 tiny dog breeds carry the mutation and many dogs are homozygous for it. This work underscores the central importance of the IGF1 pathway in controlling the tremendous size diversity of dogs. PMID:22903739

  12. Fluid Characteristics in Abdominal Aortic Aneurysms (AAAs) and Its Correlation to Thrombus Formation

    NASA Astrophysics Data System (ADS)

    Tang, Rubing; Bar-Yoseph, Pinhas Z.; Lasheras, Juan

    2008-11-01

    It has been observed that most large Abdominal Aortic Aneurysms (AAAs) develop an intraluminal thrombus as they progressively enlarge. Previous studies have suggested that the build up of the thrombus may be associated with the altered hemodynamic patterns that arise inside the AAA. We have performed a parametrical computational study of the flow patterns inside enlarging AAA to investigate the possible mechanism controlling the thrombus formation. Pulsatile blood flows were simulated in idealized models of fusiform aneurysms with different dilatation ratios and the effects of shear-activated platelet accumulation and platelet/wall interaction were evaluated based on the calculated flow fields. The platelet activation level (PAL) was determined by computing the integral over time of flow shear stresses exerted over the platelets as they are transported throughout the aneurysm. Our results have shown that the values of PAL in AAAs are in fact smaller than the maximum value obtained in a healthy abdominal aorta. However, we show that the transportation of blood cells towards the wall and the formation of stagnation points on the aneurysm's wall play more significant roles in thrombus formation than PAL.

  13. Closure of Left Atrial Appendage With Persistent Distal Thrombus Using an Amplatzer Amulet Occluder.

    PubMed

    Lange, Mathias; Bültel, Helmut; Weglage, Heinrich; Löffeld, Patrick; Wichter, Thomas

    2016-09-01

    A 73-year-old patient with permanent atrial fibrillation presented for left atrial appendage (LAA) occlusion. Transesophageal echocardiography demonstrated a thrombus in the distal LAA. This image series illustrates a "no touch" technique that was used to ensure successful implantation of an Amplatzer Amulet LAA occlusion device without the use of an embolization protection system. PMID:27591691

  14. Left atrial ball thrombus with acute mesenteric ischemia: anesthetic management and role of transesophageal echocardiography.

    PubMed

    Makhija, Neeti; Malankar, Dhananjay; Singh, Pooja; Goyal, Sameer; Patel, Kartik; Jagia, Priya

    2014-01-01

    A 62 year old female with severe mitral stenosis, large left atrial ball thrombus and acute mesenteric ischemia emergently underwent mitral valve replacement, left atrial clot removal and emergency laparotomy for mesenteric ischemia. Peri-operative management issues, particularly, the anesthetic challenges and the role of transesophageal echocardiography are discussed.

  15. Angioscopic findings before and after thrombus-related drug-eluting stent failure.

    PubMed

    Kotani, Jun-ichi; Nanto, Shinsuke; Ueda, Yasunori; Uematsu, Masaaki; Nishino, Masami; Miyazaki, Shunichi; Yasaka, Yoshinori; Yasuda, Satoshi; Mizuno, Kyoichi

    2015-07-01

    Drug-eluting stent (DES) failure and conditions thereafter remain issues of concern despite generational advancements in DES technology. Registry data and pathological investigations have shown a variety of causes of late stent thrombosis and very late stent thrombosis. On the other hand, clinical imaging including serial studies can provide information on the conditions during the event, the previous status of the lesion, and the healing process after stent implantation. Therefore we investigated thrombus-related DES failure using coronary angioscopy (CAS), which is a robust tool for thrombus assessment. Five out of 8 thrombotic DES failures were documented during urgent repeat percutaneous coronary intervention (repeat PCI). Four patients underwent CAS before the event, and 5 patients were followed using CAS after repeat PCI for DES failure. Among these cases, there were data before and after the event in 4 patients, which highlighted various patterns of healing after repeat PCI for thrombus-related DES failure, including erosion and yellow plaque underneath the DES. The cause of thrombus formation in this series was delayed healing process, but other possible triggers included restenosis, insufficient DAPT duration, neoatherosclerosis, and vasospasm. In addition to these findings being consistent with previous segmental postmortem studies, invasive imaging modalities can provide data on more than just the event itself, such as sequential comparison and lesion features of the survivor. Accumulation of this knowledge would contribute to generating new hypothesis in the future. PMID:25666526

  16. A Thrombus Generation Model Applied to Aneurysms Treated with Shape Memory Polymer Foam and Metal Coils

    NASA Astrophysics Data System (ADS)

    Horn, John; Ortega, Jason; Hartman, Jonathan; Maitland, Duncan

    2015-11-01

    To prevent their rupture, intracranial aneurysms are often treated with endovascular metal coils which fill the aneurysm sac and isolate it from the arterial flow. Despite its widespread use, this method can result in suboptimal outcomes leading to aneurysm recurrence. Recently, shape memory polymer foam has been proposed as an alternative aneurysm filler. In this work, a computational model has been developed to predict thrombus formation in blood in response to such cardiovascular implantable devices. The model couples biofluid and biochemical phenomena present as the blood interacts with a device and stimulates thrombus formation. This model is applied to simulations of both metal coil and shape memory polymer foam treatments within an idealized 2D aneurysm geometry. Using the predicted thrombus responses, the performance of these treatments is evaluated and compared. The results suggest that foam-treated aneurysms may fill more quickly and more completely with thrombus than coil-filled aneurysms, potentially leading to improved long-term aneurysm healing. This work was performed in part under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  17. A systems approach to hemostasis: 3. Thrombus consolidation regulates intrathrombus solute transport and local thrombin activity.

    PubMed

    Stalker, Timothy J; Welsh, John D; Tomaiuolo, Maurizio; Wu, Jie; Colace, Thomas V; Diamond, Scott L; Brass, Lawrence F

    2014-09-11

    Hemostatic thrombi formed after a penetrating injury have a distinctive structure in which a core of highly activated, closely packed platelets is covered by a shell of less-activated, loosely packed platelets. We have shown that differences in intrathrombus molecular transport emerge in parallel with regional differences in platelet packing density and predicted that these differences affect thrombus growth and stability. Here we test that prediction in a mouse vascular injury model. The studies use a novel method for measuring thrombus contraction in vivo and a previously characterized mouse line with a defect in integrin αIIbβ3 outside-in signaling that affects clot retraction ex vivo. The results show that the mutant mice have a defect in thrombus consolidation following vascular injury, resulting in an increase in intrathrombus transport rates and, as predicted by computational modeling, a decrease in thrombin activity and platelet activation in the thrombus core. Collectively, these data (1) demonstrate that in addition to the activation state of individual platelets, the physical properties of the accumulated mass of adherent platelets is critical in determining intrathrombus agonist distribution and platelet activation and (2) define a novel role for integrin signaling in the regulation of intrathrombus transport rates and localization of thrombin activity. PMID:24951426

  18. The ability of winter grazing to reduce wildfire size, intensity, and fire-induced plant mortality was not demonstrated: A comment on Davies et al. (2015)

    EPA Science Inventory

    A recent study by Davies et al. sought to test whether winter grazing could reduce wildfire size, fire behavior metrics, and fire-induced plant mortality in shrub-grasslands. The authors concluded that ungrazed rangelands may experience more fire-induced mortality of native peren...

  19. The ability of winter grazing to reduce wildfire size, intensity, and fire-induced plant mortality was not demonstrated: a comment on Davies et al. (2015)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent study by Davies et al. sought to test whether winter grazing could reduce wildfire size, fire behavior and intensity metrics, and fire-induced plant mortality in shrub-grasslands. The authors concluded that ungrazed rangelands may experience fire-induced mortality of native perennial bunchg...

  20. Using measured equipment load profiles to 'right-size' HVACsystems and reduce energy use in laboratory buildings (Pt. 2)

    SciTech Connect

    Mathew, Paul; Greenberg, Steve; Frenze, David; Morehead, Michael; Sartor, Dale; Starr, William

    2005-06-29

    There is a general paucity of measured equipment load datafor laboratories and other complex buildings and designers often useestimates based on nameplate rated data or design assumptions from priorprojects. Consequently, peak equipment loads are frequentlyoverestimated, and load variation across laboratory spaces within abuilding is typically underestimated. This results in two design flaws.Firstly, the overestimation of peak equipment loads results in over-sizedHVAC systems, increasing initial construction costs as well as energy usedue to inefficiencies at low part-load operation. Secondly, HVAC systemsthat are designed without accurately accounting for equipment loadvariation across zones can significantly increase simultaneous heatingand cooling, particularly for systems that use zone reheat fortemperature control. Thus, when designing a laboratory HVAC system, theuse of measured equipment load data from a comparable laboratory willsupport right-sizing HVAC systems and optimizing their configuration tominimize simultaneous heating and cooling, saving initial constructioncosts as well as life-cycle energy costs.In this paper, we present datafrom recent studies to support the above thesis. We first presentmeasured equipment load data from two sources: time-series measurementsin several laboratory modules in a university research laboratorybuilding; and peak load data for several facilities recorded in anational energy benchmarking database. We then contrast this measureddata with estimated values that are typically used for sizing the HVACsystems in these facilities, highlighting the over-sizing problem. Next,we examine the load variation in the time series measurements and analyzethe impact of this variation on energy use, via parametric energysimulations. We then briefly discuss HVAC design solutions that minimizesimultaneous heating and cooling energy use.

  1. Dendritic Nonlinearities Reduce Network Size Requirements and Mediate ON and OFF States of Persistent Activity in a PFC Microcircuit Model

    PubMed Central

    Papoutsi, Athanasia; Sidiropoulou, Kyriaki; Poirazi, Panayiota

    2014-01-01

    Technological advances have unraveled the existence of small clusters of co-active neurons in the neocortex. The functional implications of these microcircuits are in large part unexplored. Using a heavily constrained biophysical model of a L5 PFC microcircuit, we recently showed that these structures act as tunable modules of persistent activity, the cellular correlate of working memory. Here, we investigate the mechanisms that underlie persistent activity emergence (ON) and termination (OFF) and search for the minimum network size required for expressing these states within physiological regimes. We show that (a) NMDA-mediated dendritic spikes gate the induction of persistent firing in the microcircuit. (b) The minimum network size required for persistent activity induction is inversely proportional to the synaptic drive of each excitatory neuron. (c) Relaxation of connectivity and synaptic delay constraints eliminates the gating effect of NMDA spikes, albeit at a cost of much larger networks. (d) Persistent activity termination by increased inhibition depends on the strength of the synaptic input and is negatively modulated by dADP. (e) Slow synaptic mechanisms and network activity contain predictive information regarding the ability of a given stimulus to turn ON and/or OFF persistent firing in the microcircuit model. Overall, this study zooms out from dendrites to cell assemblies and suggests a tight interaction between dendritic non-linearities and network properties (size/connectivity) that may facilitate the short-memory function of the PFC. PMID:25077940

  2. A Case of Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS) Syndrome with Intracardiac Thrombus [corrected].

    PubMed

    Joo, Jung-Chul; Seol, Myung Do; Yoon, Jin Won; Lee, Young Soo; Kim, Dong-Keun; Choi, Yong Hoon; Ahn, Hyo Seong; Cho, Wook Hyun

    2013-03-01

    Myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) is a multisystem clinical syndrome manifested by mitochondrial myopathy, encephalopathy, lactic acidosis and recurrent stroke-like episodes. A 27-year-old female with MELAS syndrome presented with cerebral infarction. Echocardiography revealed a thrombus attached to the apex of the hypertrophied left ventricle, with decreased systolic function. The embolism of the intracardiac thrombus might have been the cause of stroke. There should be more consideration given to the increased possibility of intracardiac thrombus formation when a MELAS patient with cardiac involvement is encountered.

  3. N-acetylcysteine reduces the size and activity of von Willebrand factor in human plasma and mice.

    PubMed

    Chen, Junmei; Reheman, Adili; Gushiken, Francisca C; Nolasco, Leticia; Fu, Xiaoyun; Moake, Joel L; Ni, Heyu; López, José A

    2011-02-01

    Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disease characterized by systemic microvascular thrombosis caused by adhesion of platelets to ultra-large vWF (ULVWF) multimers. These multimers accumulate because of a deficiency of the processing enzyme ADAMTS13. vWF protein forms long multimers from homodimers that first form through C-terminal disulfide bonds and then join through their N termini by further disulfide bonding. N-acetylcysteine (NAC) is an FDA-approved drug that has long been used to treat chronic obstructive lung disease and acetaminophen toxicity and is known to function in the former disorder by reducing mucin multimers. Here, we examined whether NAC could reduce vWF multimers, which polymerize in a manner similar to mucins. In vitro, NAC reduced soluble plasma-type vWF multimers in a concentration-dependent manner and rapidly degraded ULVWF multimer strings extruded from activated ECs. The effect was preceded by reduction of the intrachain disulfide bond encompassing the platelet-binding A1 domain. NAC also inhibited vWF-dependent platelet aggregation and collagen binding. Injection of NAC into ADAMTS13-deficient mice led to the rapid resolution of thrombi produced by ionophore treatment of the mesenteric venules and reduced plasma vWF multimers. These results suggest that NAC may be a rapid and effective treatment for patients with TTP. PMID:21266777

  4. Salt Stress Reduces Root Meristem Size by Nitric Oxide-Mediated Modulation of Auxin Accumulation and Signaling in Arabidopsis1[OPEN

    PubMed Central

    Liu, Wen; Li, Rong-Jun; Han, Tong-Tong; Cai, Wei; Fu, Zheng-Wei

    2015-01-01

    The development of the plant root system is highly plastic, which allows the plant to adapt to various environmental stresses. Salt stress inhibits root elongation by reducing the size of the root meristem. However, the mechanism underlying this process remains unclear. In this study, we explored whether and how auxin and nitric oxide (NO) are involved in salt-mediated inhibition of root meristem growth in Arabidopsis (Arabidopsis thaliana) using physiological, pharmacological, and genetic approaches. We found that salt stress significantly reduced root meristem size by down-regulating the expression of PINFORMED (PIN) genes, thereby reducing auxin levels. In addition, salt stress promoted AUXIN RESISTANT3 (AXR3)/INDOLE-3-ACETIC ACID17 (IAA17) stabilization, which repressed auxin signaling during this process. Furthermore, salt stress stimulated NO accumulation, whereas blocking NO production with the inhibitor Nω-nitro-l-arginine-methylester compromised the salt-mediated reduction of root meristem size, PIN down-regulation, and stabilization of AXR3/IAA17, indicating that NO is involved in salt-mediated inhibition of root meristem growth. Taken together, these findings suggest that salt stress inhibits root meristem growth by repressing PIN expression (thereby reducing auxin levels) and stabilizing IAA17 (thereby repressing auxin signaling) via increasing NO levels. PMID:25818700

  5. Marine reserves reduce risk of climate-driven phase shift by reinstating size- and habitat-specific trophic interactions.

    PubMed

    Ling, S D; Johnson, C R

    2012-06-01

    Spatial closures in the marine environment are widely accepted as effective conservation and fisheries management tools. Given increasing human-derived stressors acting on marine ecosystems, the need for such effective action is urgently clear. Here we explore mechanisms underlying the utility of marine reserves to reinstate trophic dynamics and to increase resilience of kelp beds against climate-driven phase shift to sea urchin barrens on the rapidly warming Tasmanian east coast. Tethering and tagging experiments were used to examine size- and shelter-specific survival of the range-extending sea urchin Centrostephanus rodgersii (Diadematidae) translocated to reefs inside and outside no-take Tasmanian marine reserves. Results show that survival rates of C. rodgersii exposed on flat reef substratum by tethering were approximately seven times (small urchins 10.1 times; large urchins 6.1 times) lower on protected reef within marine reserve boundaries (high abundance of large predatory-capable lobsters) compared to fished reef (large predatory lobsters absent). When able to seek crevice shelter, tag-resighting models estimated that mortality rates of C. rodgersii were lower overall but remained 3.3 times (small urchins 2.1 times; large urchins 6.4 times) higher in the presence of large lobsters inside marine reserves, with higher survival of small urchins owing to greater access to crevices relative to large urchins. Indeed, shelter was 6.3 times and 3.1 times more important to survival of small and large urchins, respectively, on reserved relative to fished reef. Experimental results corroborate with surveys throughout the range extension region, showing greater occurrence of overgrazing on high-relief rocky habitats where shelter for C. rodgersii is readily available. This shows that ecosystem impacts mediated by range extension of such habitat-modifying organisms will be heterogeneous in space, and that marine systems with a more natural complement of large and thus

  6. Marine reserves reduce risk of climate-driven phase shift by reinstating size- and habitat-specific trophic interactions.

    PubMed

    Ling, S D; Johnson, C R

    2012-06-01

    Spatial closures in the marine environment are widely accepted as effective conservation and fisheries management tools. Given increasing human-derived stressors acting on marine ecosystems, the need for such effective action is urgently clear. Here we explore mechanisms underlying the utility of marine reserves to reinstate trophic dynamics and to increase resilience of kelp beds against climate-driven phase shift to sea urchin barrens on the rapidly warming Tasmanian east coast. Tethering and tagging experiments were used to examine size- and shelter-specific survival of the range-extending sea urchin Centrostephanus rodgersii (Diadematidae) translocated to reefs inside and outside no-take Tasmanian marine reserves. Results show that survival rates of C. rodgersii exposed on flat reef substratum by tethering were approximately seven times (small urchins 10.1 times; large urchins 6.1 times) lower on protected reef within marine reserve boundaries (high abundance of large predatory-capable lobsters) compared to fished reef (large predatory lobsters absent). When able to seek crevice shelter, tag-resighting models estimated that mortality rates of C. rodgersii were lower overall but remained 3.3 times (small urchins 2.1 times; large urchins 6.4 times) higher in the presence of large lobsters inside marine reserves, with higher survival of small urchins owing to greater access to crevices relative to large urchins. Indeed, shelter was 6.3 times and 3.1 times more important to survival of small and large urchins, respectively, on reserved relative to fished reef. Experimental results corroborate with surveys throughout the range extension region, showing greater occurrence of overgrazing on high-relief rocky habitats where shelter for C. rodgersii is readily available. This shows that ecosystem impacts mediated by range extension of such habitat-modifying organisms will be heterogeneous in space, and that marine systems with a more natural complement of large and thus

  7. Absorption and Bioavailability of Nano-Size Reduced Calcium Citrate Fortified Milk Powder in Ovariectomized and Ovariectomized-Osteoporosis Rats.

    PubMed

    Erfanian, Arezoo; Mirhosseini, Hamed; Rasti, Babak; Hair-Bejo, Mohd; Bin Mustafa, Shuhaimi; Abd Manap, Mohd Yazid

    2015-06-24

    The aim of this study was to evaluate the effects of fortification and nano-size reduction on calcium absorption and bioavailability of milk powder formula in sham, ovariectomized, and ovariectomized-osteoporosis rats as a menopause and menopause-osteoporosis model. Skim milk powder and skim milk powder fortified with calcium citrate and the suitable doses of inulin, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and vitamins D3, K1, and B6 were formulated based on the North American and Western European recommended dietary allowances. Optimization on cycle and pressure of high-pressure homogenizer was done to produce nano-fortified milk powder. In vivo study demonstrated that fortification and calcium citrate nano-fortified milk powder increased absorption and bioavailability of calcium, as well as bone stiffness and bone strength in sham, ovariectomized, and ovariectomized-osteoporosis rats. This study successfully developed an effective fortified milk powder for food application.

  8. Absorption and Bioavailability of Nano-Size Reduced Calcium Citrate Fortified Milk Powder in Ovariectomized and Ovariectomized-Osteoporosis Rats.

    PubMed

    Erfanian, Arezoo; Mirhosseini, Hamed; Rasti, Babak; Hair-Bejo, Mohd; Bin Mustafa, Shuhaimi; Abd Manap, Mohd Yazid

    2015-06-24

    The aim of this study was to evaluate the effects of fortification and nano-size reduction on calcium absorption and bioavailability of milk powder formula in sham, ovariectomized, and ovariectomized-osteoporosis rats as a menopause and menopause-osteoporosis model. Skim milk powder and skim milk powder fortified with calcium citrate and the suitable doses of inulin, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and vitamins D3, K1, and B6 were formulated based on the North American and Western European recommended dietary allowances. Optimization on cycle and pressure of high-pressure homogenizer was done to produce nano-fortified milk powder. In vivo study demonstrated that fortification and calcium citrate nano-fortified milk powder increased absorption and bioavailability of calcium, as well as bone stiffness and bone strength in sham, ovariectomized, and ovariectomized-osteoporosis rats. This study successfully developed an effective fortified milk powder for food application. PMID:26022498

  9. Angiogenesis Is Induced and Wound Size Is Reduced by Electrical Stimulation in an Acute Wound Healing Model in Human Skin

    PubMed Central

    Ud-Din, Sara; Sebastian, Anil; Giddings, Pamela; Colthurst, James; Whiteside, Sigrid; Morris, Julie; Nuccitelli, Richard; Pullar, Christine; Baguneid, Mo; Bayat, Ardeshir

    2015-01-01

    Angiogenesis is critical for wound healing. Insufficient angiogenesis can result in impaired wound healing and chronic wound formation. Electrical stimulation (ES) has been shown to enhance angiogenesis. We previously showed that ES enhanced angiogenesis in acute wounds at one time point (day 14). The aim of this study was to further evaluate the role of ES in affecting angiogenesis during the acute phase of cutaneous wound healing over multiple time points. We compared the angiogenic response to wounding in 40 healthy volunteers (divided into two groups and randomised), treated with ES (post-ES) and compared them to secondary intention wound healing (control). Biopsy time points monitored were days 0, 3, 7, 10, 14. Objective non-invasive measures and H&E analysis were performed in addition to immunohistochemistry (IHC) and Western blotting (WB). Wound volume was significantly reduced on D7, 10 and 14 post-ES (p = 0.003, p = 0.002, p<0.001 respectively), surface area was reduced on days 10 (p = 0.001) and 14 (p<0.001) and wound diameter reduced on days 10 (p = 0.009) and 14 (p = 0.002). Blood flow increased significantly post-ES on D10 (p = 0.002) and 14 (p = 0.001). Angiogenic markers were up-regulated following ES application; protein analysis by IHC showed an increase (p<0.05) in VEGF-A expression by ES treatment on days 7, 10 and 14 (39%, 27% and 35% respectively) and PLGF expression on days 3 and 7 (40% on both days), compared to normal healing. Similarly, WB demonstrated an increase (p<0.05) in PLGF on days 7 and 14 (51% and 35% respectively). WB studies showed a significant increase of 30% (p>0.05) on day 14 in VEGF-A expression post-ES compared to controls. Furthermore, organisation of granulation tissue was improved on day 14 post-ES. This randomised controlled trial has shown that ES enhanced wound healing by reduced wound dimensions and increased VEGF-A and PLGF expression in acute cutaneous wounds, which further substantiates the role of ES in up

  10. Caspase-dependent and serine protease-dependent DNA fragmentation of myocytes in the ischemia-reperfused rabbit heart: these inhibitors do not reduce infarct size.

    PubMed

    Minatoguchi, S; Kariya, T; Uno, Y; Arai, M; Nishida, Y; Hashimoto, K; Wang, N; Aoyama, T; Takemura, G; Fujiwara, T; Fujiwara, H

    2001-10-01

    Some infarcted myocytes undergo caspase-dependent DNA fragmentation, but serine protease-dependent DNA fragmentation may also be involved. There is controversy regarding whether caspase inhibitors can reduce infarct size, so the present study investigated whether serine protease inhibitor can reduce the DNA fragmentation of infarcted myocytes and whether serine protease or caspase inhibitors attenuates myocardial infarct size in Japanese white rabbits without collateral circulation. Rabbits were subjected to 30-min coronary occlusion followed by 48-h reperfusion. A vehicle (dimethylsulfoxide, control group, n=8) or Z-Val-Ala-Asp(Ome)-CH2F (ZVAD-fmk, a caspase inhibitor, ZVAD group, 0.8 mg/kg iv at 20 min before coronary occlusion and 0.8 mg/kg at 90 min after reperfusion, n=8) or 3,4-dichloroisocoumarin (DCI, a serine protease inhibitor, 2 mg/kg iv at 20 min before coronary occlusion, DCI group, n=8) was administered. Animals were killed at 48h after reperfusion for the detection of myocardial infarct size and at 4h after reperfusion for the detection of dUTP nick end-labeling (TUNEL)-positive myocytes, the electrophoretic pattern of DNA fragmentation and ultrastructural analysis. The left ventricle (LV) was excised and sliced. The myocardial infarct size as a percentage of the area at risk was assessed by triphenyltetrazolium chloride staining. DNA fragmentation was assessed by in situ TUNEL at the light microscopic level. ZVAD and DCI significantly reduced the mean blood pressure during reperfusion without affecting heart rate. There was no significant difference in the % area at risk (AAR) of LV among the 3 groups (control: 26.3+/-3.0%; ZVAD: 25.6+/-2.6%; DCI: 25.6+/-2.0%). The % infarct size as a percentage of the AAR in the ZVAD group (41.3+/-4.5%) and the DCI group (50.4+/-3.8%) was not significantly different from the control group (43.5+/-4.5%). However, the percent DNA fragmentation in the infarcted area in the ZVAD (3.5+/-0.8%) and DCI groups (4

  11. Resolving Thrombus in the Left Atrial Appendage by Edoxaban Treatment after Acute Ischemic Stroke: Report of 2 Cases.

    PubMed

    Saito, Shin; Shindo, Seigo; Tsudaka, Shun; Uchida, Kazutaka; Shirakawa, Manabu; Yoshimura, Shinichi

    2016-10-01

    Here we report first 2 cases of patients with nonvalvular atrial fibrillation with acute cardioembolic stroke in whom thrombi in the left atrial appendage (LAA) were resolved by edoxaban administration. Case 1 reports an 86-year-old woman who suddenly showed right hemiparesis and aphasia due to occlusion of the left middle cerebral artery. She received mechanical thrombectomy and recovered neurologically. Transesophageal echocardiography (TEE) performed on day 1 demonstrated thrombus in the LAA. The thrombus was resolved on day 13 after initiation of edoxaban (30 mg once daily) instead of warfarin, which was administered before stroke onset. Case 2 reports a 49-year-old man who was admitted because of the sudden onset of left hemiparesis and aphasia. TEE demonstrated thrombus in the LAA on day 4, and edoxaban therapy (60 mg once daily) was initiated. The thrombus resolution was observed on day 16, and no embolic stroke occurred. PMID:27562709

  12. Chromium-Modified Li4Ti5O12 with a Synergistic Effect of Bulk Doping, Surface Coating, and Size Reducing.

    PubMed

    Zou, Hailin; Liang, Xin; Feng, Xuyong; Xiang, Hongfa

    2016-08-24

    Bulk doping, surface coating, and size reducing are three strategies for improving the electrochemical properties of Li4Ti5O12 (LTO). In this work, chromium (Cr)-modified LTO with a synergistic effect of bulk doping, surface coating, and size reducing is synthesized by a facile sol-gel method. X-ray diffraction (XRD) and Raman analysis prove that Cr dopes into the LTO bulk lattice, which effectively inhibits the generation of TiO2 impurities. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) verifies the surface coating of Li2CrO4 on the LTO surface, which decreases impedance of the LTO electrode. More importantly, the size of LTO particles can be significantly reduced from submicroscale to nanoscale as a result of the protection of the Li2CrO4 surface layer and the suppression from Cr atoms on the long-range order in the LTO lattice. As anode material, Li4-xCr3xTi5-2xO12 (x = 0.1) delivers a reversible capacity of 141 mAh g(-1) at 10 °C, and over 155 mAh g(-1) at 1 °C after 1000 cycles. Therefore, the Cr-modified Li4Ti5O12 prepared via a sol-gel method has potential for applications in high-power, long-life lithium-ion batteries. PMID:27479172

  13. Reduced molecular size and altered disaccharide composition of cerebral chondroitin sulfate upon Alzheimer’s pathogenesis in mice

    PubMed Central

    Zhang, Zui; Ohtake-Niimi, Shiori; Kadomatsu, Kenji; Uchimura, Kenji

    2016-01-01

    ABSTRACT Alzheimer’s disease (AD) is a progressive disorder leading to cognitive impairment and neuronal loss. Cerebral extracellular accumulation and deposition of amyloid ß plaques is a pathological hallmark of AD. Chondroitin sulfate (CS) is an extracellular component abundant in the brain. CS is a sulfated glycosaminoglycan covalently attached to a core protein, forming chondroitin sulfate proteoglycan. The structure of CS is heterogeneous with sulfation modification and elongation of the chain. The structural diversity of CS allows it to play various roles in the brain. Increasing evidence has shown that CS promotes aggregation of amyloid ß peptides into higher-order species such as insoluble amyloid ß fibrils. Difficulties in the structural analysis of brain CS, as well as its heterogeneity, limit the study of potential roles of CS in AD pathology. Here we established a microanalysis method with reversed-phase ion-pair high performance liquid chromatography and found that CS in the brains of Tg2576 AD model mice show a lower molecular size and an increased ratio of CS-B motif di-sulfated disaccharide. Our findings provide insight into the structural changes of cerebral CS upon Alzheimer’s pathogenesis. PMID:27578913

  14. Modified carbon fibers to improve composite properties. [sizing fibers for reduced electrical conductivity and adhesion during combustion

    NASA Technical Reports Server (NTRS)

    Shepler, R. E.

    1979-01-01

    Thin coatings, 5 to 10 wt. percent, were applied to PAN-based carbon fibers. These coatings were intended to make the carbon fibers less electrically conductive or to cause fibers to stick together when a carbon fiber/epoxy composite burned. The effectiveness of the coatings in these regards was evaluated in burn tests with a test rig designed to simulate burning, impact and wind conditions which might release carbon fibers. The effect of the coatings on fiber and composite properties and handling was also investigated. Attempts at sizing carbon fibers with silicon dioxide, silicon carbide and boron nitride meet with varying degrees of success; however, none of these materials provided an electrically nonconductive coating. Coatings intended to stick carbon fibers together after a composite burned were sodium silicate, silica gel, ethyl silicate, boric acid and ammonium borate. Of these, only the sodium silicate and silica gel provided any sticking together of fibers. The amount of sticking was insufficient to achieve the desired objectives.

  15. Plasma fibrin clot phenotype independently affects intracoronary thrombus ultrastructure in patients with acute myocardial infarction.

    PubMed

    Zalewski, Jaroslaw; Bogaert, Jan; Sadowski, Marcin; Woznicka, Olga; Doulaptsis, Konstantinos; Ntoumpanaki, Maria; Ząbczyk, Michal; Nessler, Jadwiga; Undas, Anetta

    2015-06-01

    Determinants of intracoronary thrombus (ICT) composition in patients with ST-elevation myocardial infarction (STEMI) are largely unknown. We sought to investigate whether plasma fibrin phenotype and platelet reactivity affect ICT ultrastructure. We assessed the content of fibrin, platelets and erythrocytes including polyhedrocytes by scanning electron microscopy on the surface and inside ICT aspirated from 80 STEMI patients within 12 hours since chest pain onset. Plasma fibrin clot permeability (Ks), which indicates the average pore size, lysis time (t50 %), platelet reactivity index (PRI) and ADP-induced platelet aggregation (ADP5, 20µM) were evaluated on admission. All patients received aspirin and 45 (56.3 %) 600 mg of clopidogrel, 80 (60-120) min prior to aspiration. Higher content of fibrin (61.6 vs 34.3 %, P< 0.0001) and platelets (8.2 vs 4.8 %, P=0.018) and lower erythrocyte content (15.8 vs 42.9 %, P< 0.0001) were found on ICT surface compared with its inner part. After adjustment for fibrinogen, in both ICT parts fibrin content was correlated with Ks (r≤-0.55, P< 0.0001) and t50 % (r≥ 0.29, P≤ 0.02) but not with PRI and ADP5,20µM. Polyhedrocytes were observed in 16 (20 %) patients and their large amount expressed as ≥ 50 % fields of view covered by polyhedrocytes was associated with the lower PRI values (40 vs 69 %, P=0.015), but not Ks or t50 %. By multivariate regression, Ks (β=-0.62, P< 0.0001), clopidogrel pretreatment (β=-0.36, P< 0.001), ischemia time (β=0.19, P=0.044) and family history (β=0.18, P=0.049) independently predicted fibrin content in the whole ICT (R²=0.65, P< 0.0001). Formation of denser plasma fibrin clots is independently associated with high fibrin content within the ICT in STEMI. PMID:25739375

  16. Delayed treatment with intravenous basic fibroblast growth factor reduces infarct size following permanent focal cerebral ischemia in rats.

    PubMed

    Fisher, M; Meadows, M E; Do, T; Weise, J; Trubetskoy, V; Charette, M; Finklestein, S P

    1995-11-01

    Basic fibroblast growth factor (bFGF) is a polypeptide that supports the survival of brain cells (including neurons, glia, and endothelia) and protects neurons against a number of toxins and insults in vitro. This factor is also a potent dilator of cerebral pial arterioles in vivo. In previous studies, we found that intraventricularly administered bFGF reduced infarct volume in a model of focal cerebral ischemia in rats. In the current study, bFGF (45 micrograms/kg/h) in vehicle, or vehicle alone, was infused intravenously for 3 h, beginning at 30 min after permanent middle cerebral artery occlusion by intraluminal suture in mature Sprague-Dawley rats. After 24 h, neurological deficit (as assessed by a 0- to 5-point scale, with 5 = most severe) was 2.6 +/- 1.0 in vehicle-treated and 1.5 +/- 1.3 in bFGF-treated rats (mean +/- SD; N = 12 vs. 11; p = 0.009). Infarct volume was 297 +/- 65 mm3 in vehicle- and 143 +/- 135 mm3 in bFGF-treated animals (p = 0.002). During infusion, there was a modest decrease in mean arterial blood pressure but no changes in arterial blood gases or core or brain temperature in bFGF-treated rats. Autoradiography following intravenous administration of 111In-labeled bFGF showed that labeled bFGF crossed the damaged blood-brain barrier to enter the ischemic (but not the nonischemic) hemisphere. Whether the infarct-reducing effects of bFGF depend on intraparenchymal or intravascular mechanisms requires further study.

  17. Cyclosporin variably and inconsistently reduces infarct size in experimental models of reperfused myocardial infarction: a systematic review and meta-analysis.

    PubMed

    Lim, W Y; Messow, C M; Berry, C

    2012-04-01

    Cyclosporin is an immunosuppressant that has recently been proposed as a treatment to prevent reperfusion injury in acute myocardial infarction (MI). We aimed to determine the overall efficacy of cyclosporin in experimental studies of acute reperfused MI. We conducted a systematic review and stratified meta-analysis of published studies describing the efficacy of cyclosporin in experimental models of acute reperfused MI. We included all in vivo publications of cyclosporin where infarct size was measured. A literature search identified 29 potential studies of which 20 fulfilled the eligibility criteria. In these studies (involving four species of animals), cyclosporin reduced myocardial infarct size by a standardized mean (95% confidence interval) difference of -1.60 (-2.17, -1.03) compared with controls. Cyclosporin failed to demonstrate a convincing benefit in studies involving pigs. Despite this observation, the overall efficacy of cyclosporin did not differ across species (P= 0.358). The dose of cyclosporin given did not affect final infarct size (P= 0.203). Funnel plots of these data suggested heterogeneity among the studies. Cyclosporin had variable effects on infarct size compared with placebo. Cyclosporin had no effect on myocardial infarct size in swine, raising a question over the potential cardioprotective effects of cyclosporin in man.

  18. Breast Intensity-Modulated Radiation Therapy Reduces Time Spent With Acute Dermatitis for Women of All Breast Sizes During Radiation

    SciTech Connect

    Freedman, Gary M. Li Tianyu; Nicolaou, Nicos; Chen Yan; Ma, Charlie C.-M.; Anderson, Penny R.

    2009-07-01

    Purpose: To study the time spent with radiation-induced dermatitis during a course of radiation therapy for breast cancer in women treated with conventional or intensity-modulated radiation therapy (IMRT). Methods and Materials: The study population consisted of 804 consecutive women with early-stage breast cancer treated with breast-conserving surgery and radiation from 2001 to 2006. All patients were treated with whole-breast radiation followed by a boost to the tumor bed. Whole-breast radiation consisted of conventional wedged photon tangents (n = 405) earlier in the study period and mostly of photon IMRT (n = 399) in later years. All patients had acute dermatitis graded each week of treatment. Results: The breakdown of the cases of maximum acute dermatitis by grade was as follows: 3%, Grade 0; 34%, Grade 1; 61%, Grade 2; and 2%, Grade 3. The breakdown of cases of maximum toxicity by technique was as follows: 48%, Grade 0/1, and 52%, Grade 2/3, for IMRT; and 25%, Grade 0/1, and 75%, Grade 2/3, for conventional radiation therapy (p < 0.0001). The IMRT patients spent 82% of weeks during treatment with Grade 0/1 dermatitis and 18% with Grade 2/3 dermatitis, compared with 29% and 71% of patients, respectively, treated with conventional radiation (p < 0.0001). Furthermore, the time spent with Grade 2/3 toxicity was decreased in IMRT patients with small (p = 0.0015), medium (p < 0.0001), and large (p < 0.0001) breasts. Conclusions: Breast IMRT is associated with a significant decrease both in the time spent during treatment with Grade 2/3 dermatitis and in the maximum severity of dermatitis compared with that associated with conventional radiation, regardless of breast size.

  19. Warring arthropod societies: Social spider colonies can delay annihilation by predatory ants via reduced apparency and increased group size.

    PubMed

    Keiser, Carl N; Wright, Colin M; Pruitt, Jonathan N

    2015-10-01

    Sociality provides individuals with benefits via collective foraging and anti-predator defense. One of the costs of living in large groups, however, is increased apparency to natural enemies. Here, we test how the individual-level and collective traits of spider societies can increase the risk of discovery and death by predatory ants. We transplanted colonies of the social spider Stegodyphus dumicola into a habitat dense with one of their top predators, the pugnacious ant Anoplolepis custodiens. With three different experiments, we test how colony-wide survivorship in a predator-dense habitat can be altered by colony apparency (i.e., the presence of a capture web), group size, and group composition (i.e., the proportion of bold and shy personality types present). We also test how spiders' social context (i.e., living solitarily vs. among conspecifics) modifies their behaviour toward ants in their capture web. Colonies with capture webs intact were discovered by predatory ants on average 25% faster than colonies with the capture web removed, and all discovered colonies eventually collapsed and succumbed to predation. However, the lag time from discovery by ants to colony collapse was greater for colonies containing more individuals. The composition of individual personality types in the group had no influence on survivorship. Spiders in a social group were more likely to approach ants caught in their web than were isolated spiders. Isolated spiders were more likely to attack a safe prey item (a moth) than they were to attack ants and were more likely to retreat from ants after contact than they were after contact with moths. Together, our data suggest that the physical structures produced by large animal societies can increase their apparency to natural enemies, though larger groups can facilitate a longer lag time between discovery and demise. Lastly, the interaction between spiders and predatory ants seems to depend on the social context in which spiders reside

  20. Warring arthropod societies: Social spider colonies can delay annihilation by predatory ants via reduced apparency and increased group size.

    PubMed

    Keiser, Carl N; Wright, Colin M; Pruitt, Jonathan N

    2015-10-01

    Sociality provides individuals with benefits via collective foraging and anti-predator defense. One of the costs of living in large groups, however, is increased apparency to natural enemies. Here, we test how the individual-level and collective traits of spider societies can increase the risk of discovery and death by predatory ants. We transplanted colonies of the social spider Stegodyphus dumicola into a habitat dense with one of their top predators, the pugnacious ant Anoplolepis custodiens. With three different experiments, we test how colony-wide survivorship in a predator-dense habitat can be altered by colony apparency (i.e., the presence of a capture web), group size, and group composition (i.e., the proportion of bold and shy personality types present). We also test how spiders' social context (i.e., living solitarily vs. among conspecifics) modifies their behaviour toward ants in their capture web. Colonies with capture webs intact were discovered by predatory ants on average 25% faster than colonies with the capture web removed, and all discovered colonies eventually collapsed and succumbed to predation. However, the lag time from discovery by ants to colony collapse was greater for colonies containing more individuals. The composition of individual personality types in the group had no influence on survivorship. Spiders in a social group were more likely to approach ants caught in their web than were isolated spiders. Isolated spiders were more likely to attack a safe prey item (a moth) than they were to attack ants and were more likely to retreat from ants after contact than they were after contact with moths. Together, our data suggest that the physical structures produced by large animal societies can increase their apparency to natural enemies, though larger groups can facilitate a longer lag time between discovery and demise. Lastly, the interaction between spiders and predatory ants seems to depend on the social context in which spiders reside.

  1. Comparison of 180-degree and 90-degree needle rotation to reduce wound size in PIT-injected juvenile Chinook salmon

    SciTech Connect

    Bryson, Amanda J.; Woodley, Christa M.; Karls, Rhonda K.; Hall, Kathleen D.; Weiland, Mark A.; Deng, Zhiqun; Carlson, Thomas J.; Eppard, Matthew B.

    2013-04-30

    Animal telemetry, which requires the implantation of passive transponders or active transmitters, is used to monitor and assess fish stock and conservation to gain an understanding of fish movement and behavior. As new telemetry technologies become available, studies of their effects on species of interest are imperative as is development of implantation techniques. In this study, we investigated the effects of bevel rotation (0-, 90-, 180-degree axis rotation) on wound extent, tag loss, and wound healing rates in juvenile Chinook salmon injected with an 8-gauge needle, which is required for implantation of the novel injectable Juvenile Salmon Acoustic Telemetry Systems (JSATS) acoustic transmitter or large passive integrated transponder (PIT) tags. Although the injection sites were not closed after injection (e.g., with sutures or glue), there were no mortalities, dropped tags, or indications of fungus, ulceration, and/or redness around the wound. On Day 0 and post-implantation Day 7, the 90-degree bevel rotation produced smaller wound extent than the 180-degree bevel rotation. No axis rotation (0-degrees) resulted in the PIT tag frequently misleading or falling out upon injection. The results of this study indicated the 90-degree bevel rotation was the more efficient technique, produced less wound extent. Given the wound extent compared to size of fish, we recommend researchers should consider a 90-degree rotation over the 180-degree rotation in telemetry studies. Highlights •Three degrees of needle rotation were examined for effects in Chinook salmon. •Mortality, tag loss, wound extent, healing, and infection indicators were measured. •There were no mortalities, tag loss, or indications of infection. •The 90-degree needle rotation through Day 7 produced the smallest wound extent.

  2. [A Case of Carotid Free-Floating Thrombus Treated by Carotid Ultrasonography-Guided Endovascular Approach].

    PubMed

    Otawa, Masato; Kinkori, Takeshi; Watanabe, Kenichi; Ando, Ryo; Tambara, Masao; Arima, Toru

    2016-06-01

    We experienced a case of carotid free-floating thrombus treated by carotid ultrasonography-guided endovascular approach. A 63-year-old man was brought to our hospital with the chief complaint of sudden onset left hemiplegia. MRI revealed acute infarction of the right MCA territory due to the right M1 occlusion. Carotid ultrasonography showed a pedunculated, polypoid mobile plaque floating with the cardiac beat. We attempted ultrasonography-guided endovascular treatment. Under proximal balloon protection, the floating plaque was successfully aspirated into the Penumbra aspiration catheter. Carotid stent was also placed to stabilize the residual pedicle of the plaque. Aspirated plaque was identified as fresh thrombus by pathological examination. Carotid ultrasonography-guided endovascular approach was effective for getting the picture of real-time dynamics of the carotid FFT. PMID:27270147

  3. Adrenal cortical carcinoma with tumor thrombus extension into the right atrium: A case report

    PubMed Central

    WANG, YIMIN; ZHOU, FENG; PAN, HAO; JIN, BAIYE

    2016-01-01

    Adrenal cortical carcinoma (ACC) is a rare aggressive malignant tumor associated with a poor prognosis. Patients with ACC usually present with abnormal hormone secretion, tumor growth or encroachment on the surrounding viscera. An early diagnosis of ACC is considered challenging. The present study reports a case of ACC with tumor thrombus extension into the inferior vena cava and right atrium. A 33-year-old male patient exhibited symptoms of gynecomastia and abdominal distention, which were due to the abnormal hormone secretion levels and to the presence of a large mass in the right adrenal gland. An en bloc resection of the tumor was the selected treatment option. Extirpation of the tumor thrombus was performed by means of extracorporeal circulation. No signs of metastasis or recurrence were identified at the 1-month follow-up. PMID:27313728

  4. Takotsubo cardiomyopathy with left ventricular thrombus presenting as critical limb ischaemia.

    PubMed

    Gulsin, Gaurav; Serna, Solange; Morris, Clare; Taher, Abutariq; Loke, Ian

    2016-08-01

    Takotsubo cardiomyopathy (TC) is a rare condition, characterized by acute left ventricular (LV) dysfunction in the absence of flow-limiting coronary artery disease, usually provoked by a physical or emotional stressor. The condition is far more common in women. The commonest presenting symptoms in patients with TC are chest pain and shortness of breath, often mimicking an acute coronary syndrome. A number of complications of TC are recognized, and very rarely patients experience cardioembolic phenomena secondary to LV thrombus formation in TC. We present the case of a 48-year-old lady presenting with peripheral limb ischaemia, subsequently found to have an LV thrombus secondary to TC. Diagnosis of TC was made challenging by the absence of chest pain. She required urgent arterial embolectomy and was treated with 6-month oral anticoagulation therapy. She was also commenced on beta-blocker and angiotensin-converting enzyme inhibitor treatment for the management of LV dysfunction. PMID:27679725

  5. [A case of left atria subendocardial thrombus with 
sick sinus syndrome].

    PubMed

    Liang, Xiongfei; Yang, Yifeng

    2016-09-28

    The clinical data for a patient with sick sinus syndrome was retrospectively analyzed. The patient was treated because of his heart palpitations and the increased chest pain. The patient admitted to the hospital under consideration for the left atrial tumor dependent on the echocardiography findings. After the CT scan and the dynamic ECG examination, the patient successfully underwent the left atrial tumor resection, atrial septal repair and cardiac pacing lead installation. The postoperative pathological diagnosis showed that the infective endocarditis and left atrial thrombus in left atrium was cured. The patient was discharged after postoperative anti-inflammatory therapy. By analyzing the reasons for misdignosis before or during surgery, the possible mechanisms for left atrial subendocardial thrombus have been found. This study suggests that it is necessary to combine imaging diagnosis and clinical observations to distinguish tumor from excrescence. PMID:27640803

  6. Atrial Thrombus in a Premature Newborn Following Cardio-Pulmonary Resuscitation.

    PubMed

    Ali, Syed Rehan; Ahmed, Shakeel; Aslam, Nadeem; Lohana, Heeramani

    2016-06-01

    Critically ill newborns, whether term or preterm, are at great risk for developing symptomatic thromboembolic disease. Comorbidities like inflammation, DIC, fluctuations in cardiac output, congenital heart disease, as well as central venous or arterial catheters, are the predisposing risk factors. Clinically symptomatic or asymptomatic cases are usually picked up by echocardiography, usually done for other indications. Management usually comprises of observation, heparin therapy, thrombo-embolectomy, and catheter directed revascularization. We present a case of premature neonate who developed thrombus at inter-atrial septum as a possible consequence of cardiopulmonary resuscitation, detected by echocardiography. Conversely, there is always a possibility of paradoxical emboli in neonates with patent foramen ovale (PFO). Subsequent clinical course remained asymptomatic and baby was discharged home after 6 weeks with cardiac follow-up. Atrial septal findings of organized clot/thrombus in asymptomatic newborns need to be correlated with the details of neonatal care. Long-term follow-up is dependent on underlying pathology. PMID:27376221

  7. Takotsubo cardiomyopathy with left ventricular thrombus presenting as critical limb ischaemia

    PubMed Central

    Gulsin, Gaurav; Serna, Solange; Morris, Clare; Taher, Abutariq; Loke, Ian

    2016-01-01

    Takotsubo cardiomyopathy (TC) is a rare condition, characterized by acute left ventricular (LV) dysfunction in the absence of flow-limiting coronary artery disease, usually provoked by a physical or emotional stressor. The condition is far more common in women. The commonest presenting symptoms in patients with TC are chest pain and shortness of breath, often mimicking an acute coronary syndrome. A number of complications of TC are recognized, and very rarely patients experience cardioembolic phenomena secondary to LV thrombus formation in TC. We present the case of a 48-year-old lady presenting with peripheral limb ischaemia, subsequently found to have an LV thrombus secondary to TC. Diagnosis of TC was made challenging by the absence of chest pain. She required urgent arterial embolectomy and was treated with 6-month oral anticoagulation therapy. She was also commenced on beta-blocker and angiotensin-converting enzyme inhibitor treatment for the management of LV dysfunction.

  8. A case of carbon monoxide poisoning with thrombus in the heart: a case report.

    PubMed

    Yildirim, Cuma; Günay, Nurullah; Büyükaslan, Hasan; Küçükdurmaz, Zekeriya; Bozkurt, Selim

    2005-12-15

    Carbon monoxide is a nonirritant, odorless, colorless gas, and is lighter than air. It is an end product of the incomplete combustion of hydrocarbons. Its effects are most prominent in organs sensitive to oxygen deprivation, such as the heart, brain, and kidney. Carbon monoxide poisoning becomes more abundant in winter and at cold places. In Turkey, every year we see several deaths due to poisonous gas leaks from coal or wood stoves. Deaths particularly due to hypoxia-related central nervous system damage and ventricular dysrhythmias are observed. On the other hand, an association between thromboembolic accidents and carbon monoxide poisoning has been shown in literature. Thromboembolic accidents in the mesenteric, central nervous system, and extremities are reported. However, no atrial thrombus has been mentioned. In this study, a case of an atrial thrombus associated with carbon monoxide poisoning following a diagnosis of carbon monoxide poisoning and treatment in the emergency room is reported and the literature is revisited. PMID:16282157

  9. Biomechanical behaviour of cerebral aneurysm and its relation with the formation of intraluminal thrombus: a patient-specific modelling study.

    PubMed

    Wang, Xiaohong; Li, Xiaoyang

    2013-01-01

    Cerebral aneurysm is an irreversible dilatation causing intracranial haemorrhage with severe complications. It is assumed that the biomechanical factor plays a significant role in the development of cerebral aneurysm. However, reports on the correlations between the formation of intraluminal thrombus and the flow pattern, wall shear stress (WSS) distribution of the cerebral aneurysm as well as wall compliance are still limited. In this research, patient-specific numerical simulation was carried out for three cerebral aneurysms based on magnetic resonance imaging (MRI) data-sets. The interaction between pulsatile blood and aneurysm wall was taken into account. The biomechanical behaviour of cerebral aneurysm and its relation with the formation of intraluminal thrombus was studied systematically. The results of the numerical simulation indicated that the region of low blood flow velocity and the region of swirling recirculation were nearly coincident with each other. Besides, there was a significant correlation between the slow swirling flow and the location of thrombus deposition. Excessively low WSS was also found to have strong association with the regions of thrombus formation. Moreover, the relationship between cerebral aneurysm compliance and thrombus deposition was discovered. The patient-specific modelling study based on fluid-structure interaction) may provide a basis for future investigation on the prediction of thrombus formation in cerebral aneurysm. PMID:22292428

  10. REDUCED INFARCT SIZE AND ACCUMULATION OF MICROGLIA IN RATS TREATED WITH WIN 55,212-2 AFTER NEONATAL STROKE

    PubMed Central

    Fernández-López, David; Faustino, Joel; Derugin, Nikita; Wendland, Michael; Lizasoain, Ignacio; Moro, Maria A.; Vexler, Zinaida S.

    2012-01-01

    Cannabinoids have emerged as brain protective agents under neurodegenerative conditions. Many neuroprotective actions of cannabinoids depend on the activation of specific receptors, cannabinoid receptor type 1 (CB1R) and type 2 (CB2R). The aim of the present study was to determine whether the CB2R and CB1R agonist WIN 55,212-2 (WIN) protects neonatal brain against focal cerebral ischemia-reperfusion and whether anti-inflammatory mechanisms play a role in protection. 7-day-old rats were subjected to 90 minutes middle cerebral artery occlusion (MCAO) and injured rats identified by diffusion-weighted MRI during the occlusion. After reperfusion rats were subcutaneously administered 1mg/kg of WIN or vehicle twice daily until sacrifice. MCAO led to increased mRNA expression of CB2R (but not CB1R), chemokine receptors (CCR2 and CX3CR1) and cytokines (IL-1β and TNFα), as well as increased protein expression of chemokines MCP-1 and MIP-1α and microglial activation 24 hours after MCAO. WIN administration significantly reduced microglial activation at this point and attenuated infarct volume and microglial accumulation and proliferation in the injured cortex 72 hours after MCAO. Cumulatively, our results show that the cannabinoid agonist WIN protects against neonatal focal stroke in part due to inhibitory effects on microglia. PMID:22285309

  11. Loss of the Drosophila melanogaster DEAD box protein Ddx1 leads to reduced size and aberrant gametogenesis.

    PubMed

    Germain, Devon R; Li, Lei; Hildebrandt, Matthew R; Simmonds, Andrew J; Hughes, Sarah C; Godbout, Roseline

    2015-11-15

    Mammalian DDX1 has been implicated in RNA trafficking, DNA double-strand break repair and RNA processing; however, little is known about its role during animal development. Here, we report phenotypes associated with a null Ddx1 (Ddx1(AX)) mutation generated in Drosophila melanogaster. Ddx1 null flies are viable but significantly smaller than control and Ddx1 heterozygous flies. Female Ddx1 null flies have reduced fertility with egg chambers undergoing autophagy, whereas males are sterile due to disrupted spermatogenesis. Comparative RNA sequencing of control and Ddx1 null third instars identified several transcripts affected by Ddx1 inactivation. One of these, Sirup mRNA, was previously shown to be overexpressed under starvation conditions and implicated in mitochondrial function. We demonstrate that Sirup is a direct binding target of Ddx1 and that Sirup mRNA is differentially spliced in the presence or absence of Ddx1. Combining Ddx1 null mutation with Sirup dsRNA-mediated knock-down causes epistatic lethality not observed in either single mutant. Our data suggest a role for Drosophila Ddx1 in stress-induced regulation of splicing.

  12. Worm-like thrombus in left main coronary artery after cytostatic treatment.

    PubMed

    Karavelioglu, Yusuf; Ekicibasi, Erkan; Tanalp, Ali C; Karapinar, Hekim; Aung, Soe M

    2010-07-01

    This paper reports a 43-year-old patient who had a large, mobile, worm-like thrombus in the left main coronary artery after receiving a chemotherapy regimen containing cisplatin, bleomycin and etoposide for a nonseminomatous testes tumor. The patient was successfully treated with thrombolytic therapy. Physicians should be aware that thrombotic events may be observed after the administration of certain chemotherapeutic agents, particularly cisplatin.

  13. [THE THROMBUS FORMATION IN THE PROSTHESIS AS A REACTION OF ORGANISM ON ITS MATERIAL].

    PubMed

    Alekseyeva, T A; Gupalo, Yu M; Kolomoets, A M; Lazarenko, O N; Lazarenko, G O; Litvin, P M; Lohs, I V; Smorzhevskiy, V J; Stepkin, V I

    2016-04-01

    Abstract Vascular prostheses, excised because of their functional properties loss, were studied. Using different methods there was established, that this complication is caused by the thrombus formation as a reaction of organism on the prosthesis material. The testing procedure on compatibility was proposed, using atomic-power microscope. Components of a patient immunity may identify the prosthesis material and start the rejection mechanisms in case of negative reaction. PMID:27434951

  14. Recurrent Stroke due to Patent Foramen Ovale Closure Device Thrombus Eight Years after Implantation.

    PubMed

    Kodankandath, Thomas V; Mishra, Sanskriti; Libman, Richard B; Wright, Paul

    2016-09-01

    Patent foramen ovale (PFO) is a common heart defect and is found in about 25% of the general population. Although randomized trials have failed to show the superiority of percutaneous closure of PFO over medical management, the number of patients with closure device placement has grown over the years. Delayed complications from PFO closure are rare. We present a case of cardioembolic stroke secondary to a mobile thrombus on a PFO closure device 8 years after implantation. PMID:27444520

  15. Iliac artery mural thrombus formation. Effect of antiplatelet therapy on 111In-platelet deposition in baboons

    SciTech Connect

    Hanson, S.R.; Paxton, L.D.; Harker, L.A.

    1986-09-01

    To measure the rate, extent, and time course of arterial mural thrombus formation in vivo and to assess the effects of antiplatelet therapy in that setting, we have studied autologous /sup 111/In-platelet deposition induced by experimental iliac artery aneurysms in baboons. Scintillation camera imaging analyses were performed at 1, 24, 48, and 72 hours after implantation of the device. Correction for tissue attenuation was determined by using a small, comparably located /sup 111/In source implanted at the time of surgery. In five animals, /sup 111/In-platelet activity accumulated progressively after device implantation, reaching a maximum after the third day. Repeat image analysis carried out 2 weeks after the surgical procedure also showed progressive accumulation of /sup 111/In-platelets over 3 days but at markedly reduced amounts as compared with the initial study. In five additional animals, treatment with a combination of aspirin and dipyridamole begun 1 hour after surgical implantation reduced /sup 111/In-platelet deposition to negligible levels by the third day. Although platelet survival time was shortened and platelet turnover was reciprocally increased in all operated animals, platelet survival and turnover were not affected by antiplatelet therapy. We conclude that, in contrast to platelet survival and turnover measurements, /sup 111/In-platelet imaging is a reliable and sensitive method for localizing and quantifying focal arterial thrombi and for assessing the effects of antiplatelet therapy.

  16. Nicorandil prevents sirolimus-induced production of reactive oxygen species, endothelial dysfunction, and thrombus formation.

    PubMed

    Aizawa, Ken; Takahari, Youko; Higashijima, Naoko; Serizawa, Kenichi; Yogo, Kenji; Ishizuka, Nobuhiko; Endo, Koichi; Fukuyama, Naoto; Hirano, Katsuya; Ishida, Hideyuki

    2015-03-01

    Sirolimus (SRL) is widely used to prevent restenosis after percutaneous coronary intervention. However, its beneficial effect is hampered by complications of thrombosis. Several studies imply that reactive oxygen species (ROS) play a critical role in endothelial dysfunction and thrombus formation. The present study investigated the protective effect of nicorandil (NIC), an anti-angina agent, on SRL-associated thrombosis. In human coronary artery endothelial cells (HCAECs), SRL stimulated ROS production, which was prevented by co-treatment with NIC. The preventive effect of NIC on ROS was abolished by 5-hydroxydecanoate but not by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one. NIC also inhibited SRL-induced up-regulation of NADPH oxidase subunit p22(phox) mRNA. Co-treatment with NIC and SRL significantly up-regulated superoxide dismutase 2. NIC treatment significantly improved SRL-induced decrease in viability of HCAECs. The functional relevance of the preventive effects of NIC on SRL-induced ROS production and impairment of endothelial viability was investigated in a mouse model of thrombosis. Pretreatment with NIC inhibited the SRL-induced acceleration of FeCl3-initiated thrombus formation and ROS production in the testicular arteries of mice. In conclusion, NIC prevented SRL-induced thrombus formation, presumably due to the reduction of ROS and to endothelial protection. The therapeutic efficacy of NIC could represent an additional option in the prevention of SRL-related thrombosis.

  17. Right Ventricular Thrombus in a 36-Year-Old Man with Factor V Leiden

    PubMed Central

    Hajsadeghi, Shokoufeh; Naghshin, Roozbeh; Hejrati, Maral; Kerman, Scott Reza Jafarian

    2015-01-01

    Abstract Factor V Leiden deficiency is the most common hereditary hypercoagulable disease in the United States and involves 5% of the Caucasian population. Up to 30% of patients who present with deep vein thrombosis (DVT) or pulmonary thromboembolism present with this condition. This is a case report of a 36-year-old man who experienced one episode of DVT within the previous year and was admitted to our hospital due to productive coughs and hemoptysis. Paraclinical studies demonstrated a right ventricular thrombus. Additional investigation was done to find the underlying cause. Laboratory tests were positive for Factor V Leiden mutation. Other factors for hypercoagulability states were normal. Given that Factor V Leiden mutation is a life-threatening condition with a relatively high prevalence and considering its thrombogenesis, screening tests are necessary in young patients without obvious reasons for recurrent thrombus formation. It seems that medical noninvasive treatments can be an alternative therapy to surgery when a ventricular thrombus is suspected in these patients. PMID:26157463

  18. A Computational Model for Thrombus Formation in Response to Cardiovascular Implantable Devices

    NASA Astrophysics Data System (ADS)

    Horn, John; Ortega, Jason; Maitland, Duncan

    2014-11-01

    Cardiovascular implantable devices elicit complex physiological responses within blood. Notably, alterations in blood flow dynamics and interactions between blood proteins and biomaterial surface chemistry may lead to the formation of thrombus. For some devices, such as stents and heart valves, this is an adverse outcome. For other devices, such as embolic aneurysm treatments, efficient blood clot formation is desired. Thus a method to study how biomedical devices induce thrombosis is paramount to device development and optimization. A multiscale, multiphysics computational model is developed to predict thrombus formation within the vasculature. The model consists of a set of convection-diffusion-reaction partial differential equations for blood protein constituents involved in the progression of the clotting cascades. This model is used to study thrombus production from endovascular devices with the goal of optimizing the device design to generate the desired clotting response. This work was performed in part under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  19. The EP3 Agonist Sulprostone Enhances Platelet Adhesion But Not Thrombus Formation Under Flow Conditions.

    PubMed

    Pasterk, Lisa; Philipose, Sonia; Eller, Kathrin; Marsche, Gunther; Heinemann, Akos; Schuligoi, Rufina

    2015-01-01

    Platelets express the EP2, EP3 and EP4 receptors. Prostaglandin (PG) E2 has a biphasic effect on platelets. Low concentrations of PGE2 enhance platelet aggregation through the activation of the EP3 receptors, while at high concentrations it attenuates aggregation via the EP4 receptor. Consequently, EP3 receptor inhibition was shown to inhibit artherothrombosis, but had no influence on bleeding time in vivo. In this study, we investigated the role of the EP3 receptor in adhesion and thrombus formation under flow conditions in vitro. The EP3 agonist sulprostone caused an increase in the adhesion of washed platelets to fibrinogen as well as to collagen under low shear stress, an effect that was blocked by the EP3 antagonist L-798106. In contrast, when whole blood was perfused over collagen-coated surfaces, sulprostone did not enhance binding and thrombus formation of platelets on collagen; at high concentrations it even attenuated this response. We conclude that in more physiological models of thrombus formation, the role for EP3 receptors is limited, indirectly suggesting that the primary action of PGE2 in haemostasis might be an inhibitory one. PMID:26228833

  20. Platelet protein disulfide isomerase is required for thrombus formation but not for hemostasis in mice.

    PubMed

    Kim, Kyungho; Hahm, Eunsil; Li, Jing; Holbrook, Lisa-Marie; Sasikumar, Parvathy; Stanley, Ronald G; Ushio-Fukai, Masuko; Gibbins, Jonathan M; Cho, Jaehyung

    2013-08-01

    Protein disulfide isomerase (PDI) derived from intravascular cells is required for thrombus formation. However, it remains unclear whether platelet PDI contributes to the process. Using platelet-specific PDI-deficient mice, we demonstrate that PDI-null platelets have defects in aggregation and adenosine triphosphate secretion induced by thrombin, collagen, and adenosine diphosphate. Such defects were rescued by wild-type but not mutant PDI, indicating that the isomerase activity of platelet surface PDI is critical for the regulatory effect. PDI-deficient platelets expressed increased levels of intracellular ER protein 57 (ERp57) and ERp72. Platelet PDI regulated αIIbβ3 integrin activation but not P-selectin exposure, Ca(2+) mobilization, β3-talin1 interaction, or platelet spreading on immobilized fibrinogen. Inhibition of ERp57 further diminished αIIbβ3 integrin activation and aggregation of activated PDI-deficient platelets, suggesting distinct roles of PDI and ERp57 in platelet functions. We found that platelet PDI is important for thrombus formation on collagen-coated surfaces under shear. Intravital microscopy demonstrates that platelet PDI is important for platelet accumulation but not initial adhesion and fibrin generation following laser-induced arteriolar injury. Tail bleeding time in platelet-specific PDI-deficient mice were not significantly increased. Our results provide important evidence that platelet PDI is essential for thrombus formation but not for hemostasis in mice. PMID:23788140

  1. Left ventricular thrombus in patients with acute myocardial infarction:Case report and Caribbean focused update.

    PubMed

    Potu, Cr; Tulloch-Reid, Ee; Baugh, Ds; Madu, Ec

    2012-01-01

    Despite the well documented benefit of echocardiography in acute coronary syndromes, its wide-scale use in the Caribbean is limited by access, health literacy and affordability. Because of the limited use of echocardiography in the region, routine complications of acute myocardial infarction (AMI) are not fully appreciated and may go unrecognized, further contributing to increased cardiovascular morbidity and mortality. It is therefore necessary to bring focus to this common clinical condition and highlight the clinical utility of echocardiography in facilitating timely and accurate diagnosis. We report here a case of large left ventricular (LV) thrombus in a patient with AMI. Coronary angiography showed completely occluded left anterior descending artery (LAD) with angiographically normal remaining vessels. Immediate anticoagulation was commenced with heparin and overlapped with warfarin. No Primary Angioplasty (PA) was done based on the evidence from occluded artery trial. LV thrombus was completely resolved on echocardiography at three months. No evidence of thrombo-embolism was found during the resolution of LV thrombus.

  2. Retrievable Vena Cava Filters in Major Trauma Patients: Prevalence of Thrombus Within the Filter

    SciTech Connect

    Mahrer, Arie; Zippel, Douglas; Garniek, Alexander; Golan, Gil; Bensaid, Paul; Simon, Daniel; Rimon, Uri

    2008-07-15

    The purpose of this study was to report the prevalence of thrombus within a retrievable vena cava filter inserted prophylactically in major trauma patients referred for filter extraction. Between November 2002 and August 2005, 80 retrievable inferior vena cava filters (68 Optease and 12 Gunther-Tulip) were inserted into critically injured trauma patients (mean injury severity score 33.5). The filters were inserted within 1 to 6 (mean 2) days of injury. Thirty-seven patients were referred for filter removal (32 with Optease and 5 with Gunther-Tulip). The indwelling time was 7 to 22 (mean 13) days. All patients underwent inferior vena cavography prior to filter removal. There were no insertion-related complications and all filters were successfully deployed. Forty-three (54%) of the 80 patients were not referred for filter removal, as these patients continued to have contraindications to anticoagulation. Thirty-seven patients (46%) were referred for filter removal. In eight of them (22%) a large thrombus was seen within the filters and they were left in place, all with the Optease device. The other 29 filters (36%) were removed uneventfully.We conclude that the relatively high prevalence of intrafilter thrombi with the Optease filter may be explained by either spontaneous thrombus formation or captured emboli.

  3. Topical application of a cleanser containing extracts of Diospyros kaki folium, Polygonum cuspidatum and Castanea crenata var. dulcis reduces skin oil content and pore size in human skin

    PubMed Central

    LEE, BO MI; AN, SUNGKWAN; KIM, SOO-YEON; HAN, HYUN JOO; JEONG, YU-JIN; LEE, KYOUNG-ROK; ROH, NAM KYUNG; AHN, KYU JOONG; AN, IN-SOOK; CHA, HWA JUN

    2015-01-01

    The effects of skin pores on skin topographic features can be reduced by decreasing excessive production and accumulation of sebum and elimination of comedones. Therefore, a cosmetic cleanser that regulates sebum homeostasis is required. In the present study, the effects of a cosmetic cleanser that contained Diospyros kaki folium, Polygonum cuspidatum and Castanea crenata var. dulcis (DPC) was examined on the removal of sebum and on skin pore size. Healthy volunteers (n=23) aged 20–50 years were asked to apply the test materials to the face. Skin oil content, pore size, pore number and extracted sebum surface area were measured using various measurement methods. All the measurements were performed at pre- and post-application of the test materials. When the cosmetic cleanser containing DPC was applied to the skin, the oil content decreased by 77.3%, from 6.19 to 1.40. The number of skin pores decreased by 24.83%, from 125.39 to 94.23. Skin pore size decreased from 0.07 to 0.02 µm3 (71.43% decrease). The amount of extracted sebum increased by 335% when the DPC cleanser was used. Compared to the control cleanser, skin oil content was significantly decreased when the cleanser that contained DPC was used. The cleanser containing DPC also decreased pore size and number. Finally, the DPC cleanser easily removed solidified sebum from the skin. PMID:26137233

  4. Polystyrene-Divinylbenzene-Based Adsorbents Reduce Endothelial Activation and Monocyte Adhesion Under Septic Conditions in a Pore Size-Dependent Manner.

    PubMed

    Eichhorn, Tanja; Rauscher, Sabine; Hammer, Caroline; Gröger, Marion; Fischer, Michael B; Weber, Viktoria

    2016-10-01

    Endothelial activation with excessive recruitment and adhesion of immune cells plays a central role in the progression of sepsis. We established a microfluidic system to study the activation of human umbilical vein endothelial cells by conditioned medium containing plasma from lipopolysaccharide-stimulated whole blood or from septic blood and to investigate the effect of adsorption of inflammatory mediators on endothelial activation. Treatment of stimulated whole blood with polystyrene-divinylbenzene-based cytokine adsorbents (average pore sizes 15 or 30 nm) prior to passage over the endothelial layer resulted in significantly reduced endothelial cytokine and chemokine release, plasminogen activator inhibitor-1 secretion, adhesion molecule expression, and in diminished monocyte adhesion. Plasma samples from sepsis patients differed substantially in their potential to induce endothelial activation and monocyte adhesion despite their almost identical interleukin-6 and tumor necrosis factor-alpha levels. Pre-incubation of the plasma samples with a polystyrene-divinylbenzene-based adsorbent (30 nm average pore size) reduced endothelial intercellular adhesion molecule-1 expression to baseline levels, resulting in significantly diminished monocyte adhesion. Our data support the potential of porous polystyrene-divinylbenzene-based adsorbents to reduce endothelial activation under septic conditions by depletion of a broad range of inflammatory mediators. PMID:27503310

  5. Polystyrene-Divinylbenzene-Based Adsorbents Reduce Endothelial Activation and Monocyte Adhesion Under Septic Conditions in a Pore Size-Dependent Manner.

    PubMed

    Eichhorn, Tanja; Rauscher, Sabine; Hammer, Caroline; Gröger, Marion; Fischer, Michael B; Weber, Viktoria

    2016-10-01

    Endothelial activation with excessive recruitment and adhesion of immune cells plays a central role in the progression of sepsis. We established a microfluidic system to study the activation of human umbilical vein endothelial cells by conditioned medium containing plasma from lipopolysaccharide-stimulated whole blood or from septic blood and to investigate the effect of adsorption of inflammatory mediators on endothelial activation. Treatment of stimulated whole blood with polystyrene-divinylbenzene-based cytokine adsorbents (average pore sizes 15 or 30 nm) prior to passage over the endothelial layer resulted in significantly reduced endothelial cytokine and chemokine release, plasminogen activator inhibitor-1 secretion, adhesion molecule expression, and in diminished monocyte adhesion. Plasma samples from sepsis patients differed substantially in their potential to induce endothelial activation and monocyte adhesion despite their almost identical interleukin-6 and tumor necrosis factor-alpha levels. Pre-incubation of the plasma samples with a polystyrene-divinylbenzene-based adsorbent (30 nm average pore size) reduced endothelial intercellular adhesion molecule-1 expression to baseline levels, resulting in significantly diminished monocyte adhesion. Our data support the potential of porous polystyrene-divinylbenzene-based adsorbents to reduce endothelial activation under septic conditions by depletion of a broad range of inflammatory mediators.

  6. A Single-Phase Current Source Solar Inverter with Constant Instantaneous Power, Improved Reliability, and Reduced-Size DC-Link Filter

    NASA Astrophysics Data System (ADS)

    Bush, Craig R.

    This dissertation presents a novel current source converter topology that is primarily intended for single-phase photovoltaic (PV) applications. In comparison with the existing PV inverter technology, the salient features of the proposed topology are: a) the low frequency (double of line frequency) ripple that is common to single-phase inverters is greatly reduced; b) the absence of low frequency ripple enables significantly reduced size pass components to achieve necessary DC-link stiffness and c) improved maximum power point tracking (MPPT) performance is readily achieved due to the tightened current ripple even with reduced-size passive components. The proposed topology does not utilize any electrolytic capacitors. Instead an inductor is used as the DC-link filter and reliable AC film capacitors are utilized for the filter and auxiliary capacitor. The proposed topology has a life expectancy on par with PV panels. The proposed modulation technique can be used for any current source inverter where an unbalanced three-phase operation is desires such as active filters and power controllers. The proposed topology is ready for the next phase of microgrid and power system controllers in that it accepts reactive power commands. This work presents the proposed topology and its working principle supported by with numerical verifications and hardware results. Conclusions and future work are also presented.

  7. Loss of Vascular Endothelial Growth Factor A (VEGFA) Isoforms in Granulosa Cells Using pDmrt-1-Cre or Amhr2-Cre Reduces Fertility by Arresting Follicular Development and by Reducing Litter Size in Female Mice

    PubMed Central

    Sargent, Kevin M.; Lu, Ningxia; Clopton, Debra T.; Pohlmeier, William E.; Brauer, Vanessa M.; Ferrara, Napoleone; Silversides, David W.; Cupp, Andrea S.

    2015-01-01

    Because VEGFA has been implicated in follicle development, the objective of this study was to determine the effects of granulosa- and germ cell-specific VEGFA loss on ovarian morphogenesis, function, and female fertility. pDmrt1-Cre mice were mated to floxed VEGFA mice to develop granulosa-/germ cell-specific knockouts (pDmrt1-Cre;Vegfa-/-). The time from mating to first parturition was increased when pDmrt1-Cre;Vegfa-/- females were mated to control males (P = 0.0008) and tended to be longer for heterozygous females (P < 0.07). Litter size was reduced for pDmrt1-Cre;Vegfa-/- females (P < 0.007). The time between the first and second parturitions was also increased for heterozygous females (P < 0.04) and tended to be increased for pDmrt1-Cre;Vegfa-/- females (P < 0.07). pDmrt1-Cre;Vegfa-/- females had smaller ovaries (P < 0.04), reduced plasma estradiol (P < 0.007), fewer developing follicles (P < 0.008) and tended to have fewer corpora lutea (P < 0.08). Expression of Igf1r was reduced (P < 0.05); expression of Foxo3a tended to be increased (P < 0.06); and both Fshr (P < 0.1) and Sirt6 tended to be reduced (P < 0.06) in pDmrt1-Cre;Vegfa-/- ovaries. To compare VEGFA knockouts, we generated Amhr2-Cre;Vegfa-/- mice that required more time from mating to first parturition (P < 0.003) with variable ovarian size. Both lines had more apoptotic granulosa cells, and vascular staining did not appear different. Taken together these data indicate that the loss of all VEGFA isoforms in granulosa/germ cells (proangiogenic and antiangiogenic) causes subfertility by arresting follicular development, resulting in reduced ovulation rate and fewer pups per litter. PMID:25658474

  8. Sensitivity of 3D Gradient Recalled Echo Susceptibility-Weighted Imaging Technique Compared to Computed Tomography Angiography for Detection of Middle Cerebral Artery Thrombus in Acute Stroke.

    PubMed

    Agarwal, Amit; Vijay, Kanupriya; Thamburaj, Krishnamoorthy; Kanekar, Sangam; Kalapos, Paul

    2014-10-23

    We aimed at comparing the sensitivity of magnetic resonance (MR) susceptibility-weighted imaging (SWI) with computed tomography angiography (CTA) in the detection of middle cerebral artery (MCA) thrombus in acute stroke. Seventy-nine patients with acute MCA stroke was selected using our search engine software; only the ones showing restricted diffusion in the MCA territory on diffusion-weighted images were included. We finally selected 35 patients who had done both MRI (including SWI) and CTA. Twenty random subjects with completely normal MRI (including SWI) exam were selected as control. Two neuroradiologists (blinded to the presence or absence of stroke) reviewed the SW images and then compared the findings with CT angiogram (in patients with stroke). The number of MCA segments showing thrombus in each patient was tabulated to estimate the thrombus burden. Thrombus was detected on SWI in one or more MCA segments in 30 out of 35 patients, on the first review. Of the 30, SWI showed thrombus in more than one MCA segments in 7 patients. CTA depicted branch occlusion in 31 cases. Thrombus was seen on both SWI and CTA in 28 patients. Thrombus was noted in two patients on SWI only, with no corresponding abnormality seen on CTA. Two patients with acute MCA showed no vascular occlusion or thrombus on either CTA or SWI. Only two case of false-positive thrombus was reported in normal control subjects. Susceptibility-weighted images had sensitivity and specificity of 86% and 90% respectively, with positive predictive value 94%. Sensitivity was 86% for SWI, compared with 89% for CTA, and this difference was statistically insignificant (P>0.05). Of all the positive cases on CTA (31) corresponding thrombus was seen on SWI in 90% of subjects (28 of 31). Susceptibility-weighted imaging has high sensitivity for detection of thrombus in acute MCA stroke. Moreover, SWI is a powerful technique for estimation of thrombus burden, which can be challenging on CTA.

  9. Palladium nanoparticles decorated on reduced graphene oxide rotating disk electrodes toward ultrasensitive hydrazine detection: effects of particle size and hydrodynamic diffusion.

    PubMed

    Krittayavathananon, Atiweena; Srimuk, Pattarachai; Luanwuthi, Santamon; Sawangphruk, Montree

    2014-12-16

    Although metal nanoparticle/graphene composites have been widely used as the electrode in electrochemical sensors, two effects, consisting of the particle size of the nanoparticles and the hydrodynamic diffusion of analytes to the electrodes, are not yet fully understood. In this work, palladium nanoparticles/reduced graphene oxide (PdNPs/rGO) composites were synthesized using an in situ polyol method. Palladium(II) ions and graphene oxide were reduced together with a reducing agent, ethylene glycol. By varying the concentration of palladium(II) nitrate, PdNPs with different sizes were decorated on the surface of rGO sheets. The as-fabricated PdNPs/rGO rotating disk electrodes (RDEs) were investigated toward hydrazine detection. Overall, a 3.7 ± 1.4 nm diameter PdNPs/rGO RDE exhibits high performance with a rather low limit of detection of about 7 nM at a rotation speed of 6000 rpm and provides a wide linear range of 0.1-1000 μM with R(2) = 0.995 at 2000 rpm. This electrode is highly selective to hydrazine without interference from uric acid, glucose, ammonia, caffeine, methylamine, ethylenediamine, hydroxylamine, n-butylamine, adenosine, cytosine, guanine, thymine, and l-arginine. The PdNPs/rGO RDEs with larger sizes show lower detection performance. Interestingly, the detection performance of the electrodes is sensitive to the hydrodynamic diffusion of hydrazine. The as-fabricated electrode can detect trace hydrazine in wastewater with high stability, demonstrating its practical use as an electrochemical sensor. These findings may lead to an awareness of the effect of the hydrodynamic diffusion of analyte that has been previously ignored, and the 3.7 ± 1.4 nm PdNPs/rGO RDE may be useful toward trace hydrazine detection, especially in wastewater from related chemical industries.

  10. The association of interleukin 6-634C/G polymorphism with left atrial thrombus and severe spontaneous echocontrast in patients with atrial fibrillation.

    PubMed

    Deng, Xin-Tao; Jiang, Min-Hui; Zhu, Jian-Hua; Ge, Li-Jun; Guo, Jing; Gao, Shu-Ping; Zheng, Jin-Guo; Luan, Hong; Shi, Gui-Liang; Wang, Ru-Xing; Shi, Hai-Feng; Pan, Min

    2013-01-01

    Atrial fibrillation (AF) not only is an independent risk factor for death but also confers significant risk of morbidity from stroke associated with left atrial thrombus. The association of interleukin 6 (IL-6) polymorphism with thrombus in AF has not been investigated before. We carried out a case-control study in Han Chinese. The IL-6 -634C/G genotypes of 31 patients with thrombus and 45 patients without thrombus were detected by polymerase chain reaction and restriction fragment length polymorphism. The frequencies of the IL-6 genotypes (CC, CG, and GG) were 29.03%, 54.54%, and 16.13% for the patients with thrombus, and 55.56%, 40.00%, and 4.44% for the patients without thrombus, respectively (P = .0391). Compared with the CC genotype, the G allele carriers (CG + GG) had a 2.79-fold increased risk of thrombus or severe spontaneous echocontrast (SEC). These results suggest that IL-6 -634C/G polymorphism is associated with thrombus and severe SEC, and the G allele is an independent risk for thrombus and severe SEC in Han Chinese patients with AF.

  11. Cancer cell–derived microparticles bearing P-selectin glycoprotein ligand 1 accelerate thrombus formation in vivo

    PubMed Central

    Thomas, Grace M.; Panicot-Dubois, Laurence; Lacroix, Romaric; Dignat-George, Françoise; Lombardo, Dominique

    2009-01-01

    Recent publications have demonstrated the presence of tissue factor (TF)–bearing microparticles (MPs) in the blood of patients suffering from cancer. However, whether these MPs are involved in thrombosis remains unknown. We show that pancreatic and lung cancer cells produce MPs that express active TF and P-selectin glycoprotein ligand 1 (PSGL-1). Cancer cell–derived MPs aggregate platelets via a TF-dependent pathway. In vivo, cancer cell–derived MPs, but not their parent cells, infused into a living mouse accumulate at the site of injury and reduce tail bleeding time and the time to occlusion of venules and arterioles. This thrombotic state is also observed in mice developing tumors. In such mice, the amount of circulating platelet-, endothelial cell–, and cancer cell–derived MPs is increased. Endogenous cancer cell–derived MPs shed from the growing tumor are able to accumulate at the site of injury. Infusion of a blocking P-selectin antibody abolishes the thrombotic state observed after injection of MPs or in mice developing a tumor. Collectively, our results indicate that cancer cell–derived MPs bearing PSGL-1 and TF play a key role in thrombus formation in vivo. Targeting these MPs could be of clinical interest in the prevention of thrombosis and to limit formation of metastasis in cancer patients. PMID:19667060

  12. Combination of Superselective Arterial Embolization and Radiofrequency Ablation for the Treatment of a Giant Renal Angiomyolipoma Complicated with Caval Thrombus

    PubMed Central

    Stamatiou, Konstantinos N.; Moschouris, Hippocrates; Marmaridou, Kiriaki; Kiltenis, Michail; Kladis-Kalentzis, Konstantinos; Malagari, Katerina

    2016-01-01

    This is a case of a 78-year-old male patient with multiple angiomyolipomas of a solitary right kidney. The largest of these tumors (maximum diameter: 13.4 cm) caused significant extrinsic compression of the inferior vena cava complicated by thrombosis of this vessel. Treatment of thrombosis with anticoagulants had been ineffective and the patient had experienced a bleeding episode from the largest right renal angiomyolipoma, which had been treated by transarterial embolization in another institution, 4 months prior to our intervention. Our approach included superselective transarterial embolization of the dominant, right kidney angiomyolipoma with hydrogel microspheres, which was combined, 20 days later, with ultrasonographically guided radiofrequency ablation. Both interventions were uneventful. Computed tomography 2 months after ablation showed a 53% reduction in tumor volume, reduced space-occupying effect on inferior vena cava, and resolution of caval thrombus. Nine months after intervention the patient has had no recurrence of thrombosis or hemorrhage and no tumor regrowth has been observed. The combination of superselective transarterial embolization and radiofrequency ablation seems to be a feasible, safe, and efficient treatment of large renal angiomyolipomas. PMID:27293932

  13. Combination of Superselective Arterial Embolization and Radiofrequency Ablation for the Treatment of a Giant Renal Angiomyolipoma Complicated with Caval Thrombus.

    PubMed

    Stamatiou, Konstantinos N; Moschouris, Hippocrates; Marmaridou, Kiriaki; Kiltenis, Michail; Kladis-Kalentzis, Konstantinos; Malagari, Katerina

    2016-01-01

    This is a case of a 78-year-old male patient with multiple angiomyolipomas of a solitary right kidney. The largest of these tumors (maximum diameter: 13.4 cm) caused significant extrinsic compression of the inferior vena cava complicated by thrombosis of this vessel. Treatment of thrombosis with anticoagulants had been ineffective and the patient had experienced a bleeding episode from the largest right renal angiomyolipoma, which had been treated by transarterial embolization in another institution, 4 months prior to our intervention. Our approach included superselective transarterial embolization of the dominant, right kidney angiomyolipoma with hydrogel microspheres, which was combined, 20 days later, with ultrasonographically guided radiofrequency ablation. Both interventions were uneventful. Computed tomography 2 months after ablation showed a 53% reduction in tumor volume, reduced space-occupying effect on inferior vena cava, and resolution of caval thrombus. Nine months after intervention the patient has had no recurrence of thrombosis or hemorrhage and no tumor regrowth has been observed. The combination of superselective transarterial embolization and radiofrequency ablation seems to be a feasible, safe, and efficient treatment of large renal angiomyolipomas. PMID:27293932

  14. The evolution of size of the uropygial gland: mutualistic feather mites and uropygial secretion reduce bacterial loads of eggshells and hatching failures of European birds.

    PubMed

    Soler, J J; Peralta-Sánchez, J M; Martín-Platero, A M; Martín-Vivaldi, M; Martínez-Bueno, M; Møller, A P

    2012-09-01

    Potentially, pathogenic bacteria are one of the main infective agents against which a battery of chemical and physical barriers has evolved in animals. Among these are the secretions by the exocrine uropygial gland in birds. The antimicrobial properties of uropygial secretions may prevent colonization and growth of microorganisms on feathers, skin and eggshells. However, uropygial gland secretions also favour the proliferation of feather mites that feed on secretions and microorganisms living on feathers that would otherwise reach eggshells during incubation if not consumed by feather mites. Therefore, at the interspecific level, uropygial gland size (as an index of volume of uropygial secretion) should be positively related to eggshell bacterial load (i.e. the risk of egg infection), whereas eggshell bacterial loads may be negatively related to abundance of feather mites eating bacteria. Here, we explore these previously untested predictions in a comparative framework using information on eggshell bacterial loads, uropygial gland size, diversity and abundance of feather mites and hatching success of 22 species of birds. The size of the uropygial gland was positively related to eggshell bacterial loads (mesophilic bacteria and Enterobacteriaceae), and bird species with higher diversity and abundance of feather mites harboured lower bacterial density on their eggshells (Enterococcus and Staphylococcus), in accordance with the hypothesis. Importantly, eggshell bacterial loads of mesophilic bacteria, Enterococcus and Enterobacteriaceae were negatively associated with hatching success, allowing us to interpret these interspecific relationships in a functional scenario, where both uropygial glands and mutualistic feather mites independently reduce the negative effects of pathogenic bacteria on avian fitness.

  15. Lowering bile acid pool size with a synthetic farnesoid X receptor (FXR) agonist induces obesity and diabetes through reduced energy expenditure.

    PubMed

    Watanabe, Mitsuhiro; Horai, Yasushi; Houten, Sander M; Morimoto, Kohkichi; Sugizaki, Taichi; Arita, Eri; Mataki, Chikage; Sato, Hiroyuki; Tanigawara, Yusuke; Schoonjans, Kristina; Itoh, Hiroshi; Auwerx, Johan

    2011-07-29

    We evaluated the metabolic impact of farnesoid X receptor (FXR) activation by administering a synthetic FXR agonist (GW4064) to mice in which obesity was induced by a high fat diet. Administration of GW4064 accentuated body weight gain and glucose intolerance induced by the high fat diet and led to a pronounced worsening of the changes in liver and adipose tissue. Mechanistically, treatment with GW4064 decreased bile acid (BA) biosynthesis, BA pool size, and energy expenditure, whereas reconstitution of the BA pool in these GW4064-treated animals by BA administration dose-dependently reverted the metabolic abnormalities. Our data therefore suggest that activation of FXR with synthetic agonists is not useful for long term management of the metabolic syndrome, as it reduces the BA pool size and subsequently decreases energy expenditure, translating as weight gain and insulin resistance. In contrast, expansion of the BA pool size, which can be achieved by BA administration, could be an interesting strategy to manage the metabolic syndrome.

  16. Performance of a low cost MBT prior to landfilling: study of the biological treatment of size reduced MSW without mechanical sorting.

    PubMed

    Lornage, R; Redon, E; Lagier, T; Hébé, I; Carré, J

    2007-01-01

    In France, the interest in Mechanical Biological Treatment (MBT) prior to landfilling is actually growing. In the absence of acceptance criteria for the waste to be landfilled, an alternative to the intensive, high-technology MBT can only find its place in the French context if it shows substantial benefits from an environmental, economic or operational point of view. This paper presents an experiment of low-cost MBT of size reduced MSW without material splitting. The performance of an experimental, pilot-scale mechanical and biological treatment process has been studied on 37.5 Mg of raw municipal solid waste. The mechanical process has been kept simple with only coarse shredding and no material recovery. The biological treatment, which was a low-cost forced aeration process, was monitored for 25 weeks. The biogas production potential of the waste was reduced by 90% to 19 NL kgDM(-1). The initial AT4 index of 82.9 mg O2 gDM(-1) decreased to 16.0 mg O2 gDM(-1). After 25 weeks of aerobic treatment, the dry mass loss reached 37%, while the mass of waste going to landfill was reduced by 28%. The average performances of the process were explained by the biological process itself, which was not optimal, and also by the characteristics of the input waste. The high particle size of the treated waste and the high content of slowly biodegradable matter (such as paper and cardboard) may both be significant drawbacks for the biological stabilisation of waste.

  17. Synthesis of fibrinolytic active silver nanoparticle using wheat bran xylan as a reducing and stabilizing agent.

    PubMed

    Harish, B S; Uppuluri, Kiran Babu; Anbazhagan, Veerappan

    2015-11-01

    A facile synthesis of highly stable silver nanoparticles (AgNPs) was reported using a biopolymer, xylan as both a reducing and stabilizing agent. Xylan was isolated from waste biomass, wheat bran (WB) by alkaline treatment and was characterized by Fehling's test, dinitrosalicylic acid assay, FTIR, (1)H NMR and (13)C NMR. The synthesized nanoparticles were characterized by UV-Vis spectroscopy and transmission electron microscopy. The nanoparticles were polydispersed with the size ranging from 20 to 45 nm. The synthesized WB-xylan AgNPs showed excellent free radical scavenging activity. In addition, WB-xylan AgNPs showed fibrinolytic activity as evidenced by the zone of clearance in fibrin plate assay. The biomedical potential of the WB-xylan AgNPs was demonstrated by dissolution of preformed blood clots. These results suggest that the development of xylan-metal nanoparticle composite would be feasible to treat thrombus related diseases. PMID:26256330

  18. Artificial aortic valve dysfunction due to pannus and thrombus – different methods of cardiac surgical management

    PubMed Central

    Marcinkiewicz, Anna; Kośmider, Anna; Walczak, Andrzej; Zwoliński, Radosław; Jaszewski, Ryszard

    2015-01-01

    Introduction Approximately 60 000 prosthetic valves are implanted annually in the USA. The risk of prosthesis dysfunction ranges from 0.1% to 4% per year. Prosthesis valve dysfunction is usually caused by a thrombus obstructing the prosthetic discs. However, 10% of prosthetic valves are dysfunctional due to pannus formation, and 12% of prostheses are damaged by both fibrinous and thrombotic components. The authors present two patients with dysfunctional aortic prostheses who were referred for cardiac surgery. Different surgical solutions were used in the treatment of each case. Case study 1 The first patient was a 71-year-old woman whose medical history included arterial hypertension, stable coronary artery disease, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and hypercholesterolemia; she had previously undergone left-sided mastectomy and radiotherapy. The patient was admitted to the Cardiac Surgery Department due to aortic prosthesis dysfunction. Transthoracic echocardiography revealed complete obstruction of one disc and a severe reduction in the mobility of the second. The mean transvalvular gradient was very high. During the operation, pannus covering the discs’ surface was found. A biological aortic prosthesis was reimplanted without complications. Case study 2 The second patient was an 87-year-old woman with arterial hypertension, persistent atrial fibrillation, and COPD, whose past medical history included gastric ulcer disease and ischemic stroke. As in the case of the first patient, she was admitted due to valvular prosthesis dysfunction. Preoperative transthoracic echocardiography revealed an obstruction of the posterior prosthetic disc and significant aortic regurgitation. Transesophageal echocardiography and fluoroscopy confirmed the prosthetic dysfunction. During the operation, a thrombus growing around a minor pannus was found. The thrombus and pannus were removed, and normal functionality of the prosthetic valve was restored

  19. Declotting a Thrombosed Brescia-Cimino Fistula by Manual Catheter-Directed Aspiration of the Thrombus

    SciTech Connect

    Turmel-Rodrigues, Luc A E-mail: cim.stgatien@wanadoo.fr

    2005-01-15

    Acute thrombosis of native fistulae for hemodialysis occurs more rarely than for prosthetic grafts. The vascular access should be reopened as soon as possible in order to resume regular dialysis and to avoid resorting to a temporary central line. Manual aspiration is one of the numerous methods described in this setting. Clinical examination is essential to rule out local infection, which is the only serious contraindication to percutaneous maneuvers. Two introducer-sheaths are placed in a criss-cross fashion in order to gain access to the venous outflow and to the anastomosis. Access to the venous outflow is performed first in order to check the proximal extent of the thrombosis. Heparin and antibiotics are injected systemically. A similar maneuver is then performed in the direction of the anastomosis. The aspiration phase is then initiated. A 7-9 Fr aspiration catheter is pushed through the 'venous' introducer. Manual aspiration is created through a 50 ml syringe while the catheter is progressively removed with back and forth movements. The catheter and the contents of the syringe are flushed through a gauze on the working table to evaluate the amount of thrombus which has been removed and the maneuver is repeated as often as necessary to remove all the thrombus. Once all the clots located downstream from the venous introducer have been removed, any unmasked underlying stenosis is NOT dilated at this stage since it provides protection against major embolism coming from the inflow. The aspiration catheter is then pushed through the 'arterial' introducer down to the anastomosis in order to aspirate the thrombus located between the tip of the introducer and the anastomosis. Dilatation of unmasked stenoses is finally performed using high-pressure balloons. The holes made by the two introducers are closed using a U-shaped suture with interposition of a short piece of plastic and the patient is sent back to the nephrologists for dialysis.

  20. Diagnosis and treatment of early bioprosthetic malfunction in the mitral valve position due to thrombus formation.

    PubMed

    Butnaru, Adi; Shaheen, Joseph; Tzivoni, Dan; Tauber, Rachel; Bitran, Daniel; Silberman, Shuli

    2013-11-01

    Bioprosthetic valve thrombosis is uncommon and the diagnosis is often elusive and may be confused with valve degeneration. We report our experience with mitral bioprosthetic valve thrombosis and suggest a therapeutic approach. From 2002 to 2011, 149 consecutive patients who underwent mitral valve replacement with a bioprosthesis at a single center were retrospectively screened for clinical or echocardiographic evidence of valve malfunction. Nine were found to have valve thrombus. All 9 patients had their native valve preserved, representing 24% of those with preserved native valves. Five patients (group 1) presented with symptoms of congestive heart failure at 16.4 ± 12.4 months after surgery. Echocardiogram revealed homogenous echo-dense film on the ventricular surface of the bioprosthesis with elevated transvalvular gradient, resembling early degeneration. The first 2 patients underwent reoperation: valve thrombus was found and confirmed by histologic examination. Based on these, the subsequent 3 patients received anticoagulation treatment with complete thrombus resolution: mean mitral gradient decreased from 23 ± 4 to 6 ± 1 mm Hg and tricuspid regurgitation gradient decreased from 83 ± 20 to 49 ± 5 mm Hg. Four patients (group 2) were asymptomatic, but routine echocardiogram showed a discrete mass on the ventricular aspect of the valve: 1 underwent reoperation to replace the valve and 3 received anticoagulation with complete resolution of the echocardiographic findings. In conclusion, bioprosthetic mitral thrombosis occurs in about 6% of cases. In our experience, onset is early, before anticipated valve degeneration. Clinical awareness followed by an initial trial with anticoagulation is warranted. Surgery should be reserved for those who are not responsive or patients in whom the hemodynamic status does not allow delay. Nonresection of the native valve at the initial operation may play a role in the origin of this entity.

  1. A multimodality vascular imaging phantom of an abdominal aortic aneurysm with a visible thrombus

    SciTech Connect

    Allard, Louise; Chayer, Boris; Qin Zhao; Soulez, Gilles; Roy, David; Cloutier, Guy

    2013-06-15

    Purpose: With the continuous development of new stent grafts and implantation techniques, it has now become technically feasible to treat abdominal aortic aneurysms (AAA) with challenging anatomy using endovascular repair with standard, fenestrated, or branched stent-grafts. In vitro experimentations are very useful to improve stent-graft design and conformability or imaging guidance for stent-graft delivery or follow-up. Vascular replicas also help to better understand the limitation of endovascular approaches in challenging anatomy and possibly improve surgical planning or training by practicing high risk clinical procedures in the laboratory to improve outcomes in the operating room. Most AAA phantoms available have a very basic anatomy, which is not representative of the clinical reality. This paper presents a method of fabrication of a realistic AAA phantom with a visible thrombus, as well as some mechanical properties characterizing such phantom. Methods: A realistic AAA geometry replica of a real patient anatomy taken from a multidetector computed tomography (CT) scan was manufactured. To demonstrate the multimodality imaging capability of this new phantom with a thrombus visible in magnetic resonance (MR) angiography, CT angiography (CTA), digital subtraction angiography (DSA), and ultrasound, image acquisitions with all these modalities were performed by using standard clinical protocols. Potential use of this phantom for stent deployment was also tested. A rheometer allowed defining hyperelastic and viscoelastic properties of phantom materials. Results: MR imaging measurements of SNR and CNR values on T1 and T2-weighted sequences and MR angiography indicated reasonable agreement with published values of AAA thrombus and abdominal components in vivo. X-ray absorption also lay within normal ranges of AAA patients and was representative of findings observed on CTA, fluoroscopy, and DSA. Ultrasound propagation speeds for developed materials were also in

  2. A Collision Probability Model of Portal Vein Tumor Thrombus Formation in Hepatocellular Carcinoma

    PubMed Central

    Xiong, Fei

    2015-01-01

    Hepatocellular carcinoma is one of the most common malignancies worldwide, with a high risk of portal vein tumor thrombus (PVTT). Some promising results have been achieved for venous metastases of hepatocellular carcinoma; however, the etiology of PVTT is largely unknown, and it is unclear why the incidence of PVTT is not proportional to its distance from the carcinoma. We attempted to address this issue using physical concepts and mathematical tools. Finally, we discuss the relationship between the probability of a collision event and the microenvironment of the PVTT. Our formulae suggest that the collision probability can alter the tumor microenvironment by increasing the number of tumor cells. PMID:26131562

  3. Right atrial thrombus associated with subclavian catheter developed due to total parenteral nutrition application

    PubMed Central

    Sahin, Nursel; Basarici, Ibrahim; Erbasan, Ozan

    2016-01-01

    Central venous catheterization as a frequent routine clinical procedure may have significant complications. Mechanical complications may occur during catheter placement, whereas thromboembolic and infectious complications can be seen during follow-up. Total parenteral nutrition (TPN) associated central venous catheterizations may result in early mechanical complications and thrombotic and infectious complications in the long term. This paper describes a patient diagnosed as mitochondrial neurogastrointestinal encephalomyopathy requiring long-term central venous catheterization for TPN implementation, who had an infected thrombus on the catheter tip resected by cardiac surgery. PMID:27212985

  4. Infected Right Atrial Thrombus after Explantation of a Left Ventricular Assist Device

    PubMed Central

    Akay, Mehmet H.; Sirlak, Mustafa; Gregoric, Igor D.; Frazier, O. H.

    2012-01-01

    Finding the source of a fungal infection and selecting the most appropriate treatment for candidemia is often challenging for physicians, especially when the patient has a complex medical history. We describe the case of a 48-year-old woman who had persistent candidemia after undergoing explantation of a left ventricular assist device. The source of the infection was found to be a right atrial thrombus. The mass was removed, and the patient underwent aggressive treatment with micafungin. Removal of the right atrial mass, followed by potent antifungal treatment, resulted in a successful recovery. PMID:22719151

  5. Residual Inferior Vena Cava Thrombus Detected by Transesophageal Echocardiography After Resection of a Malignant Adrenal Mass.

    PubMed

    Burbano, Nelson H; Vlah, Claudene; Argalious, Maged

    2015-10-15

    A 43-year-old woman with a history of the Cushing syndrome secondary to adrenocortical carcinoma presented to the operating room for right adrenalectomy, hepatectomy, nephrectomy, and inferior vena cava (IVC) thrombectomy. Initial intraoperative transesophageal echocardiogram (TEE) confirmed the presence of an IVC tumor below the hepatic veins. Total vascular exclusion of the liver was necessary to perform the operation. A repeat TEE showed a residual thrombus within the IVC prompting an additional cavotomy to successfully remove the entire mass. The remainder of the procedure finalized uneventfully. The case highlights the importance of TEE monitoring for noncardiac surgery with thrombotic involvement of the IVC. PMID:26466307

  6. Transient Ischemic Attacks of Spinal Cord due to Abdominal Aortic Aneurysm Thrombus.

    PubMed

    Ates, Ihsan; Kaplan, Mustafa; Özçalık, Merve; Yılmaz, Nisbet

    2016-01-01

    Thrombosis due to abdominal aortic aneurysm is a rare condition that causes high mortality. Transient ischemic attack of the spinal cord can occur as a result of trash emboli from thrombus in abdominal aortic aneurysm. This condition generally occurs during operation of abdominal aortic aneurysm; very rarely, it can also be seen in laminated abdominal aortic aneurysm. Here, we present a case of a patient presenting with bilateral lower extremity paralysis resulting from transient ischemic attack of the spinal cord due to infrarenal abdominal aortic aneurysm. PMID:26520423

  7. Potential Activity, Size, and Structure of Sulfate-Reducing Microbial Communities in an Exposed, Grazed and a Sheltered, Non-Grazed Mangrove Stand at the Red Sea Coast

    PubMed Central

    Balk, Melike; Keuskamp, Joost A.; Laanbroek, Hendrikus J.

    2015-01-01

    After oxygen, sulfate is the most important oxidant for the oxidation of organic matter in mangrove forest soils. As sulfate reducers are poor competitors for common electron donors, their relative success depends mostly on the surplus of carbon that is left by aerobic organisms due to oxygen depletion. We therefore hypothesized that sulfate-cycling in mangrove soils is influenced by the size of net primary production, and hence negatively affected by mangrove degradation and exploitation, as well as by carbon-exporting waves. To test this, we compared quantitative and qualitative traits of sulfate-reducing communities in two Saudi-Arabian mangrove stands near Jeddah, where co-occurring differences in camel-grazing pressure and tidal exposure led to a markedly different stand height and hence primary production. Potential sulfate reduction rates measured in anoxic flow-through reactors in the absence and presence of additional carbon sources were significantly higher in the samples from the non-grazed site. Near the surface (0–2 cm depth), numbers of dsrB gene copies and culturable cells also tended to be higher in the non-grazed sites, while these differences were not detected in the sub-surface (4–6 cm depth). It was concluded that sulfate-reducing microbes at the surface were indeed repressed at the low-productive site as could be expected from our hypothesis. At both sites, sulfate reduction rates as well as numbers of the dsrB gene copies and viable cells increased with depth suggesting repression of sulfate reduction near the surface in both irrespective of production level. Additionally, sequence analysis of DNA bands obtained from DGGE gels based on the dsrB gene, showed a clear difference in dominance of sulfate-reducing genera belonging to the Deltaproteobacteria and the Firmicutes between sampling sites and depths. PMID:26733999

  8. Potential Activity, Size, and Structure of Sulfate-Reducing Microbial Communities in an Exposed, Grazed and a Sheltered, Non-Grazed Mangrove Stand at the Red Sea Coast.

    PubMed

    Balk, Melike; Keuskamp, Joost A; Laanbroek, Hendrikus J

    2015-01-01

    After oxygen, sulfate is the most important oxidant for the oxidation of organic matter in mangrove forest soils. As sulfate reducers are poor competitors for common electron donors, their relative success depends mostly on the surplus of carbon that is left by aerobic organisms due to oxygen depletion. We therefore hypothesized that sulfate-cycling in mangrove soils is influenced by the size of net primary production, and hence negatively affected by mangrove degradation and exploitation, as well as by carbon-exporting waves. To test this, we compared quantitative and qualitative traits of sulfate-reducing communities in two Saudi-Arabian mangrove stands near Jeddah, where co-occurring differences in camel-grazing pressure and tidal exposure led to a markedly different stand height and hence primary production. Potential sulfate reduction rates measured in anoxic flow-through reactors in the absence and presence of additional carbon sources were significantly higher in the samples from the non-grazed site. Near the surface (0-2 cm depth), numbers of dsrB gene copies and culturable cells also tended to be higher in the non-grazed sites, while these differences were not detected in the sub-surface (4-6 cm depth). It was concluded that sulfate-reducing microbes at the surface were indeed repressed at the low-productive site as could be expected from our hypothesis. At both sites, sulfate reduction rates as well as numbers of the dsrB gene copies and viable cells increased with depth suggesting repression of sulfate reduction near the surface in both irrespective of production level. Additionally, sequence analysis of DNA bands obtained from DGGE gels based on the dsrB gene, showed a clear difference in dominance of sulfate-reducing genera belonging to the Deltaproteobacteria and the Firmicutes between sampling sites and depths.

  9. Potential Activity, Size, and Structure of Sulfate-Reducing Microbial Communities in an Exposed, Grazed and a Sheltered, Non-Grazed Mangrove Stand at the Red Sea Coast.

    PubMed

    Balk, Melike; Keuskamp, Joost A; Laanbroek, Hendrikus J

    2015-01-01

    After oxygen, sulfate is the most important oxidant for the oxidation of organic matter in mangrove forest soils. As sulfate reducers are poor competitors for common electron donors, their relative success depends mostly on the surplus of carbon that is left by aerobic organisms due to oxygen depletion. We therefore hypothesized that sulfate-cycling in mangrove soils is influenced by the size of net primary production, and hence negatively affected by mangrove degradation and exploitation, as well as by carbon-exporting waves. To test this, we compared quantitative and qualitative traits of sulfate-reducing communities in two Saudi-Arabian mangrove stands near Jeddah, where co-occurring differences in camel-grazing pressure and tidal exposure led to a markedly different stand height and hence primary production. Potential sulfate reduction rates measured in anoxic flow-through reactors in the absence and presence of additional carbon sources were significantly higher in the samples from the non-grazed site. Near the surface (0-2 cm depth), numbers of dsrB gene copies and culturable cells also tended to be higher in the non-grazed sites, while these differences were not detected in the sub-surface (4-6 cm depth). It was concluded that sulfate-reducing microbes at the surface were indeed repressed at the low-productive site as could be expected from our hypothesis. At both sites, sulfate reduction rates as well as numbers of the dsrB gene copies and viable cells increased with depth suggesting repression of sulfate reduction near the surface in both irrespective of production level. Additionally, sequence analysis of DNA bands obtained from DGGE gels based on the dsrB gene, showed a clear difference in dominance of sulfate-reducing genera belonging to the Deltaproteobacteria and the Firmicutes between sampling sites and depths. PMID:26733999

  10. Machine Learning classification of MRI features of Alzheimer's disease and mild cognitive impairment subjects to reduce the sample size in clinical trials.

    PubMed

    Escudero, Javier; Zajicek, John P; Ifeachor, Emmanuel

    2011-01-01

    There is a need for objective tools to help clinicians to diagnose Alzheimer's Disease (AD) early and accurately and to conduct Clinical Trials (CTs) with fewer patients. Magnetic Resonance Imaging (MRI) is a promising AD biomarker but no single MRI feature is optimal for all disease stages. Machine Learning classification can address these challenges. In this study, we have investigated the classification of MRI features from AD, Mild Cognitive Impairment (MCI), and control subjects from ADNI with four techniques. The highest accuracy rates for the classification of controls against ADs and MCIs were 89.2% and 72.7%, respectively. Moreover, we used the classifiers to select AD and MCI subjects who are most likely to decline for inclusion in hypothetical CTs. Using the hippocampal volume as an outcome measure, we found that the required group sizes for the CTs were reduced from 197 to 117 AD patients and from 366 to 215 MCI subjects. PMID:22256186

  11. A reduced-order integral formulation to account for the finite size effect of isotropic square panels using the transfer matrix method.

    PubMed

    Bonfiglio, Paolo; Pompoli, Francesco; Lionti, Riccardo

    2016-04-01

    The transfer matrix method is a well-established prediction tool for the simulation of sound transmission loss and the sound absorption coefficient of flat multilayer systems. Much research has been dedicated to enhancing the accuracy of the method by introducing a finite size effect of the structure to be simulated. The aim of this paper is to present a reduced-order integral formulation to predict radiation efficiency and radiation impedance for a panel with equal lateral dimensions. The results are presented and discussed for different materials in terms of radiation efficiency, sound transmission loss, and the sound absorption coefficient. Finally, the application of the proposed methodology for rectangular multilayer systems is also investigated and validated against experimental data. PMID:27106325

  12. A reduced-order integral formulation to account for the finite size effect of isotropic square panels using the transfer matrix method.

    PubMed

    Bonfiglio, Paolo; Pompoli, Francesco; Lionti, Riccardo

    2016-04-01

    The transfer matrix method is a well-established prediction tool for the simulation of sound transmission loss and the sound absorption coefficient of flat multilayer systems. Much research has been dedicated to enhancing the accuracy of the method by introducing a finite size effect of the structure to be simulated. The aim of this paper is to present a reduced-order integral formulation to predict radiation efficiency and radiation impedance for a panel with equal lateral dimensions. The results are presented and discussed for different materials in terms of radiation efficiency, sound transmission loss, and the sound absorption coefficient. Finally, the application of the proposed methodology for rectangular multilayer systems is also investigated and validated against experimental data.

  13. Development of an Optical Detector of Thrombus Formation on the Pivot Bearing of a Rotary Blood Pump.

    PubMed

    Sakota, Daisuke; Fujiwara, Tatsuki; Ouchi, Katsuhiro; Kuwana, Katsuyuki; Yamazaki, Hiroyuki; Maruyama, Osamu

    2016-09-01

    Continuous optical monitoring of thrombus formation in extracorporeal mechanical circulatory support (EMCS) devices will contribute to safe, long-term EMCS. A clinically applicable optical detector must be able to distinguish among the optical characteristics of oxygen saturation (SaO2 ), hematocrit (Hct), and thrombus formation. In vitro studies of spectral changes at wavelengths from 400 to 900 nm associated with SaO2 , Hct, and thrombus formed around the top pivot bearing of a Gyro C1E3 pump were conducted. Fresh porcine blood anticoagulated with sodium citrate was circulated in a mock circuit using the pump. The SaO2 , Hct, and anticoagulation activity were altered using an oxygenator, autologous plasma, and calcium chlorite injection, respectively. Light from a xenon lamp was guided by an incident fiber perpendicularly fixed on the top bearing. This light was scattered by blood pooled between the male and female pivots. The detection fiber was perpendicularly fixed against the incident fiber, and the side-scattered light was detected and guided to a spectrophotometer. As a result, light at two different wavelengths, 420 and 810 nm, was identified as suitable for thrombus detection because it was negligibly influenced by SaO2 and was able to detect the optical characteristics of fibrin. The light at these two wavelengths responded more quickly to thrombus formation than the inlet or outlet pressure, and flow rate change. The optical changes showed the changes in Hct around the top pivot bearing, which is caused by the reduction in density of fibrin-trapped red blood cells (RBCs) due to the RBCs being swept away by the surrounding blood flow. The proposed method was also able to detect fibrin production by extracting subtle differences in the optical characteristics between the Hct and thrombus formation. PMID:27645394

  14. Multi-site thrombus imaging and fibrin content estimation with a single whole-body PET scan in rats

    PubMed Central

    Blasi, Francesco; Oliveira, Bruno L; Rietz, Tyson A.; Rotile, Nicholas J; Naha, Pratap C; Cormode, David P; Izquierdo-Garcia, David; Catana, Ciprian; Caravan, Peter

    2015-01-01

    Objective Thrombosis is a leading cause of morbidity and mortality worldwide. Current diagnostic strategies rely on imaging modalities that are specific for distinct vascular territories, but a thrombus-specific whole-body imaging approach is still missing. Moreover, imaging techniques to assess thrombus composition are underdeveloped, although therapeutic strategies may benefit from such technology. Therefore, our goal was to test whether positron emission tomography (PET) with the fibrin-binding probe 64Cu-FBP8 allows multi-site thrombus detection and fibrin content estimation. Approach and Results Thrombosis was induced in Sprague-Dawley rats (n=32) by ferric chloride application on both carotid artery and femoral vein. 64Cu-FBP8-PET/CT imaging was performed 1, 3 or 7 days after thrombosis to detect thrombus location and to evaluate age-dependent changes in target uptake. Ex vivo biodistribution, autoradiography and histopathology were performed to validate imaging results. Arterial and venous thrombi were localized on fused PET/CT images with high accuracy (97.6%, 95% confidence interval: 92–100%). A single whole-body PET/MR imaging session was sufficient to reveal the location of both arterial and venous thrombi after 64Cu-FBP8 administration. PET imaging showed that probe uptake was greater in younger clots than in older ones for both arterial and venous thrombosis (P<0.0001). Quantitative histopathology revealed an age-dependent reduction of thrombus fibrin content (P<0.001), consistent with PET results. Biodistribution and autoradiography further confirmed the imaging findings. Conclusions We demonstrated that 64Cu-FBP8-PET is a feasible approach for whole-body thrombus detection, and that molecular imaging of fibrin can provide, noninvasively, insight into clot composition. PMID:26272938

  15. Total Cavopulmonary Connection is Superior to Atriopulmonary Connection Fontan in Preventing Thrombus Formation: Computer Simulation of Flow-Related Blood Coagulation.

    PubMed

    Sughimoto, Koichi; Okauchi, Kazuki; Zannino, Diana; Brizard, Christian P; Liang, Fuyou; Sugawara, Michiko; Liu, Hao; Tsubota, Ken-Ichi

    2015-10-01

    The classical Fontan route, namely the atriopulmonary connection (APC), continues to be associated with a risk of thrombus formation in the atrium. A conversion to a total cavopulmonary connection (TCPC) from the APC can ameliorate hemodynamics for the failed Fontan; however, the impact of these surgical operations on thrombus formation remains elusive. This study elucidates the underlying mechanism of thrombus formation in the Fontan route by using a two-dimensional computer hemodynamic simulation based on a simple blood coagulation rule. Hemodynamics in the Fontan route was simulated with Navier-Stokes equations. The blood coagulation and the hemodynamics were combined using a particle method. Three models were created: APC with a square atrium, APC with a round atrium, and TCPC. To examine the effects of the venous blood flow velocity, the velocity at rest and during exercise (0.5 and 1.0 W/kg) was measured. The total area of the thrombi increased over time. The APC square model showed the highest incidence for thrombus formation, followed by the APC round, whereas no thrombus was formed in the TCPC model. Slower blood flow at rest was associated with a higher incidence of thrombus formation. The TCPC was superior to the classical APC in terms of preventing thrombus formation, due to significant blood flow stagnation in the atrium of the APC. Thus, local hemodynamic behavior associated with the complex channel geometry plays a major role in thrombus formation in the Fontan route.

  16. Histopathological examination of specimens removed during directional coronary atherectomy in patients presenting with crescendo angina show mural thrombus.

    PubMed

    Bellamy, C M; Grech, E D; Ashworth, M T; Ramsdale, D R

    1993-02-01

    Thrombus formation over a fissured coronary atheromatous plaque has been shown by post mortem histological examination to be the pathophysiological mechanism responsible for myocardial ischaemia in those patients who died following a crescendo pattern of angina. Histological examination of plaques responsible for a crescendo pattern of angina in patients who do not die has not been available until recently. We describe two patients who presented with a crescendo pattern of angina. A new technique of coronary revascularization, directional coronary atherectomy, produced symptomatic relief and resolution of myocardial ischaemia. Histological examination of material from the stenosis responsible for their myocardial ischaemia, obtained using this technique, confirmed thrombus formation overlying a fissured atheromatous plaque.

  17. Risk factors for development of left ventricular thrombus after first acute anterior myocardial infarction-association with anticardiolipin antibodies

    PubMed Central

    2010-01-01

    Background Left ventricular thrombus(LVT] formation is a frequent complication in patients with acute anterior myocardial infarction(MI). LVT is associated with increased risk of embolism and higher mortality rates after acute MI. Anticardiolipin antibodies (ACA) are immunoglobulins that react with phospholipid-binding proteins interfering with the prothrombin activator complex. The effects of phospholipids on pathophysiology of cardiovascular thrombotic events are well known. In this study, we aimed to evaluate the importance of clinical and biochemical parameters including anticardiolipin antibodies on left ventricular thrombus formation after acute anterior MI. Methods and Results Seventy patients with a first anterior AMI were prospectively and consecutively enrolled. Patients with previous MI, autoimmune disease, collagen vascular disease and arterial or venous thrombosis history were excluded from this study. At the time of hospitalization, key demographic and clinical characteristics were collected including age, gender, ethanol intake and presence of traditional risk factors for atherosclerosis (hypertension, diabetes, smoking, hyperlipidemia, positive family history). Patients were evaluated for echocardiographic data, blood chemistry and ACA. Two-dimensional and Doppler echocardiographic examinations were performed in all patients within the first week and at 14 days after MI. LV thrombus was detected in 30 (42.8%) patients. ACA IgM levels were significantly higher in the patient group with LV thrombus than in the group without thrombus (12.44 ±4.12 vs. 7.69 ± 4.25 mpl, p = 0,01). ACA IgG levels were also found higher in the group with LV thrombus (24.2 ± 7.5 vs.17.98 ± 6.45 gpl, p = 0.02). Multivariate analyses revealed diabetes mellitus, higher WMSI, lower MDT and higher ACA IgM and higher ACA IgG levels as independent predictors of left ventricular thrombus formation. Conclusions Our data demonstrate that beside the low ejection fraction, lower MDT

  18. LIGA20, a lyso derivative of ganglioside GM1, given orally after cortical thrombosis reduces infarct size and associated cognition deficit.

    PubMed Central

    Kharlamov, A; Zivkovic, I; Polo, A; Armstrong, D M; Costa, E; Guidotti, A

    1994-01-01

    A bilateral photochemically induced thrombotic lesion of rat sensorimotor cortex (approximately 3 mm in diameter and 25 mm3 in volume) is associated with a persistent cognition (learning and memory) deficit, which was evaluated with water maze tasks. The N-dichloroacetylsphingosine derivative of lysoGM1 (LIGA20) administered after the lesion either i.v. or per or reduces the infarct size by 30-40% and attenuates the associated cognition deficits, presumably by limiting the extent of damage of neurons at risk located in the surroundings of the infarcted core (i.e., area penumbra). The LIGA20 protection is dose and time dependent. Maximal protection is afforded by a single dose of LIGA20 of 34 mumol/kg i.v. 1 hr after lesion or by a dose of 270 mumol/kg per os when administered 1 hr and 24 hr after the lesion. The protective effect of LIGA20 can be observed when the drug is administered i.v. up to 6 hr after the lesion. The protective efficacy of the oral administration of LIGA20 is related to its physiochemical properties, which, unlike those of GM1, allow absorption from the gastrointestinal tract. LIGA20 given orally reaches the brain promptly and rapidly inserts into the neuronal membranes. Here, by an unknown molecular mechanism, LIGA20 selectively reduces the pathological amplification of Ca2+ signaling elicited by persistent stimulation of ionotropic glutamate receptors in the area penumbra. PMID:8022776

  19. Image-based characterization of thrombus formation in time-lapse DIC microscopy.

    PubMed

    Brieu, Nicolas; Navab, Nassir; Serbanovic-Canic, Jovana; Ouwehand, Willem H; Stemple, Derek L; Cvejic, Ana; Groher, Martin

    2012-05-01

    The characterization of thrombus formation in time-lapse DIC microscopy is of increased interest for identifying genes which account for atherothrombosis and coronary artery diseases (CADs). In particular, we are interested in large-scale studies on zebrafish, which result in large amount of data, and require automatic processing. In this work, we present an image-based solution for the automatized extraction of parameters quantifying the temporal development of thrombotic plugs. Our system is based on the joint segmentation of thrombotic and aortic regions over time. This task is made difficult by the low contrast and the high dynamic conditions observed in vivo DIC microscopic scenes. Our key idea is to perform this segmentation by distinguishing the different motion patterns in image time series rather than by solving standard image segmentation tasks in each image frame. Thus, we are able to compensate for the poor imaging conditions. We model motion patterns by energies based on the idea of dynamic textures, and regularize the model by two prior energies on the shape of the aortic region and on the topological relationship between the thrombus and the aorta. We demonstrate the performance of our segmentation algorithm by qualitative and quantitative experiments on synthetic examples as well as on real in vivo microscopic sequences.

  20. Glutamate Receptor Interacting Protein 1 Mediates Platelet Adhesion and Thrombus Formation.

    PubMed

    Modjeski, Kristina L; Ture, Sara K; Field, David J; Cameron, Scott J; Morrell, Craig N

    2016-01-01

    Thrombosis-associated pathologies, such as myocardial infarction and stroke, are major causes of morbidity and mortality worldwide. Because platelets are necessary for hemostasis and thrombosis, platelet directed therapies must balance inhibiting platelet function with bleeding risk. Glutamate receptor interacting protein 1 (GRIP1) is a large scaffolding protein that localizes and organizes interacting proteins in other cells, such as neurons. We have investigated the role of GRIP1 in platelet function to determine its role as a molecular scaffold in thrombus formation. Platelet-specific GRIP1-/- mice were used to determine the role of GRIP1 in platelets. GRIP1-/- mice had normal platelet counts, but a prolonged bleeding time and delayed thrombus formation in a FeCl3-induced vessel injury model. In vitro stimulation of WT and GRIP1-/- platelets with multiple agonists showed no difference in platelet activation. However, in vivo platelet rolling velocity after endothelial stimulation was significantly greater in GRIP1-/- platelets compared to WT platelets, indicating a potential platelet adhesion defect. Mass spectrometry analysis of GRIP1 platelet immunoprecipitation revealed enrichment of GRIP1 binding to GPIb-IX complex proteins. Western blots confirmed the mass spectrometry findings that GRIP1 interacts with GPIbα, GPIbβ, and 14-3-3. Additionally, in resting GRIP1-/- platelets, GPIbα and 14-3-3 have increased interaction compared to WT platelets. GRIP1 interactions with the GPIb-IX binding complex are necessary for normal platelet adhesion to a stimulated endothelium. PMID:27631377

  1. Automatic aortic vessel tree extraction and thrombus detection in multislice CT

    NASA Astrophysics Data System (ADS)

    Subramanyan, Krishna; Steinmiller, Melinda; Sifri, Diana; Boll, Daniel

    2003-05-01

    The abdominal aorta is the most common site for an aneurysm, which may lead to hemorrhage and death, to develop. The aim of this study was to develop a semi-automated method to de-lineate the blood flow and thrombus region, subsequently detect the centerline of these vessels to make measurements necessary for stent design from computed tomograms. We developed a robust method of tracking the aortic vessel tree from a user selected seed point using series of image processing such as fast marching method to delineate the blood flow, morphological and distance transforms methods to extract centerlines, and finally by reinitializing the fast marching in a blood filled region subtracted CT volume to obtain the thrombus borders. Fifteen patients were scanned with contrast on Mx8000 CT scanner (Philips Medical Systems), with a 1.3 mm thickness, 1.0 mm slice spacing, and a stack of 512x512x380 volume data sets were reconstructed. The automated image processing took approximately 30 to 90 seconds to compute the centerline and borders of the aortic vessel tree. We compared our results with manual and 3D volume rendering methods and found automatic method is superior in accuracy of spatial localization (0.94-0.97 ANOVA K) and accuracy of diameter determination (0.88-0.98).

  2. Tripeptide SQL Inhibits Platelet Aggregation and Thrombus Formation by Affecting PI3K/Akt Signaling.

    PubMed

    Su, Xing-li; Su, Wen; He, Zhi-long; Ming, Xin; Kong, Yi

    2015-09-01

    Centipede has been prescribed for the treatment of cardiovascular diseases in Asian countries for several hundred years. Previously, a new antiplatelet tripeptide SQL (H-Ser-Gln-Leu-OH) was isolated and characterized from centipede. In this study, we investigated its antithrombotic activities in vivo and underlying mechanism. It was found that SQL inhibited platelet aggregation induced by adenosine diphosphate, thrombin, epinephrine, and collagen and attenuated thrombus formation in both the ferric chloride-induced arterial thrombosis model and arteriovenous shunt thrombosis model in rats. It did not prolong the bleeding time in mice even at the dose of 10 mg/kg that showed potent antithrombosis effects. Molecular docking revealed that SQL binds PI3Kβ with the binding free energy of -24.341 kcal/mol, which is close to that of cocrystallized ligand (-24.220 kcal/mol). Additionally, SQL displayed inhibition on the late (180 seconds) but did not influence the early (60 seconds) Akt Ser473 phosphorylation in the immunoblot assay. These results suggest that SQL inhibits thrombus formation in vivo and that SQL inhibits PI3K-mediated signaling or even the PI3K itself in platelets. This study may help elucidate the mechanism for centipede treating cardiovascular diseases. PMID:25923322

  3. A Novel Technique for Endovascular Removal of Large Volume Right Atrial Tumor Thrombus

    SciTech Connect

    Nickel, Barbara; McClure, Timothy Moriarty, John

    2015-08-15

    Venous thromboembolic disease is a significant cause of morbidity and mortality, particularly in the setting of large volume pulmonary embolism. Thrombolytic therapy has been shown to be a successful treatment modality; however, its use somewhat limited due to the risk of hemorrhage and potential for distal embolization in the setting of large mobile thrombi. In patients where either thrombolysis is contraindicated or unsuccessful, and conventional therapies prove inadequate, surgical thrombectomy may be considered. We present a case of percutaneous endovascular extraction of a large mobile mass extending from the inferior vena cava into the right atrium using the Angiovac device, a venovenous bypass system designed for high-volume aspiration of undesired endovascular material. Standard endovascular methods for removal of cancer-associated thrombus, such as catheter-directed lysis, maceration, and exclusion, may prove inadequate in the setting of underlying tumor thrombus. Where conventional endovascular methods either fail or are unsuitable, endovascular thrombectomy with the Angiovac device may be a useful and safe minimally invasive alternative to open resection.

  4. [Successful endovascular repair of a ruptured thoracoabdominal aortic aneurysm with severe mural thrombus].

    PubMed

    Nakao, Yoshihisa; Akagi, Haruhiko; Irie, Hiroshi; Sakaguchi, Shoji; Sakai, Kei

    2014-11-01

    A 51-year-old man was transferred to our hospital on an emergency basis complaining of a sudden onset of severe left lumbar back pain. An emergency contrasted computed tomography showed a ruptured thoracoabdominal aortic aneurysm( rTAAA:Crawford classification type III). The ruptured site was near the aortic bifurcation, and the aneurysm had a relatively narrow segment with an extensive mural thrombus just below the renal arteries. Considering the high mortality of open surgery for the rTAAA and the poor general condition of the patient, we decided to perform endovascular aneurysm repair (EVAR) as a rescue procedure using the narrowed segment by the thrombus for a proximal landing zone. The abdominal part of the thoracoabdominal aortic aneurysm (TAAA) was successfully excluded with a stent graft to obtain complete hemostasis. The postoperative course was uneventful except for the need for hemodialysis. Even though there is a risk of developing late type 1 endoleak, this procedure can be a feasible option as a rescue procedure or a bridge to radical open surgery for ruptured TAAA in a specially anatomical setting like this case. PMID:25391465

  5. Tripeptide SQL Inhibits Platelet Aggregation and Thrombus Formation by Affecting PI3K/Akt Signaling.

    PubMed

    Su, Xing-li; Su, Wen; He, Zhi-long; Ming, Xin; Kong, Yi

    2015-09-01

    Centipede has been prescribed for the treatment of cardiovascular diseases in Asian countries for several hundred years. Previously, a new antiplatelet tripeptide SQL (H-Ser-Gln-Leu-OH) was isolated and characterized from centipede. In this study, we investigated its antithrombotic activities in vivo and underlying mechanism. It was found that SQL inhibited platelet aggregation induced by adenosine diphosphate, thrombin, epinephrine, and collagen and attenuated thrombus formation in both the ferric chloride-induced arterial thrombosis model and arteriovenous shunt thrombosis model in rats. It did not prolong the bleeding time in mice even at the dose of 10 mg/kg that showed potent antithrombosis effects. Molecular docking revealed that SQL binds PI3Kβ with the binding free energy of -24.341 kcal/mol, which is close to that of cocrystallized ligand (-24.220 kcal/mol). Additionally, SQL displayed inhibition on the late (180 seconds) but did not influence the early (60 seconds) Akt Ser473 phosphorylation in the immunoblot assay. These results suggest that SQL inhibits thrombus formation in vivo and that SQL inhibits PI3K-mediated signaling or even the PI3K itself in platelets. This study may help elucidate the mechanism for centipede treating cardiovascular diseases.

  6. Glutamate Receptor Interacting Protein 1 Mediates Platelet Adhesion and Thrombus Formation

    PubMed Central

    Modjeski, Kristina L.; Ture, Sara K.; Field, David J.; Cameron, Scott J.; Morrell, Craig N.

    2016-01-01

    Thrombosis-associated pathologies, such as myocardial infarction and stroke, are major causes of morbidity and mortality worldwide. Because platelets are necessary for hemostasis and thrombosis, platelet directed therapies must balance inhibiting platelet function with bleeding risk. Glutamate receptor interacting protein 1 (GRIP1) is a large scaffolding protein that localizes and organizes interacting proteins in other cells, such as neurons. We have investigated the role of GRIP1 in platelet function to determine its role as a molecular scaffold in thrombus formation. Platelet-specific GRIP1-/- mice were used to determine the role of GRIP1 in platelets. GRIP1-/- mice had normal platelet counts, but a prolonged bleeding time and delayed thrombus formation in a FeCl3-induced vessel injury model. In vitro stimulation of WT and GRIP1-/- platelets with multiple agonists showed no difference in platelet activation. However, in vivo platelet rolling velocity after endothelial stimulation was significantly greater in GRIP1-/- platelets compared to WT platelets, indicating a potential platelet adhesion defect. Mass spectrometry analysis of GRIP1 platelet immunoprecipitation revealed enrichment of GRIP1 binding to GPIb-IX complex proteins. Western blots confirmed the mass spectrometry findings that GRIP1 interacts with GPIbα, GPIbβ, and 14-3-3. Additionally, in resting GRIP1-/- platelets, GPIbα and 14-3-3 have increased interaction compared to WT platelets. GRIP1 interactions with the GPIb-IX binding complex are necessary for normal platelet adhesion to a stimulated endothelium. PMID:27631377

  7. Right Ventricular Thrombus and Cerebral Artery Aneurysm in a Patient with Behçet's Disease.

    PubMed

    Sabzi, Feridoun; Mirzaei, Samaneh; Faraji, Reza

    2016-05-01

    We report a 35-year-old woman referred to the Imam Ali Hospital, Kermanshah, Iran, in July 2014 for evaluation of postoperative dyspnoea after neurosurgery performed seven days previously for a ruptured cerebral artery aneurysm. She was known to have Behçet's disease with a history of recurrent oral and genital aphthous ulcers and uveitis. At referral, her symptoms included vertigo, dysarthria, palpitations and chest pain. Transthoracic echocardiography (TTE) revealed a large thrombus in her right ventricle outflow tract and open-heart surgery was performed eight days after the previous surgery to remove the clot. The postoperative period was complicated by transient acute renal failure, which resolved spontaneously. The patient was discharged 13 days after the cardiac surgery on warfarin, prednisolone, azathioprine and cyclophosphamide. Cyclophosphamide and azathioprine were discontinued after three months as the symptoms had completely resolved; however, prednisolone was continued due to recurrent uveitis. A 10-month follow-up TTE scan revealed no thrombus recurrence and treatment with warfarin and prednisolone was continued. PMID:27226921

  8. Engineering of plasminogen activators for targeting to thrombus and heightening thrombolytic efficacy.

    PubMed

    Absar, S; Gupta, N; Nahar, K; Ahsan, F

    2015-09-01

    Thrombotic occlusion of the coronary artery, which triggers acute myocardial infarction, is one of the major causes of death in the USA. Currently, arterial occlusions are treated with intravenous plasminogen activators (PAs), which dissolve the clot by activating plasminogen. However, PAs indiscriminately generate plasmin, which depletes critical clotting factors (fibrinogen, factor V, and factor VIII), precipitates a lytic state in the blood, and produces bleeding complications in a large patient population. PAs have been extensively investigated to achieve thrombus specificity, to attenuate the bleeding risk, and to widen their clinical applications. In this review, we discuss various strategies that have been pursued since the beginning of thrombolytic therapy. We review the biotechnological approaches that have been used to develop mutant and chimeric PAs for thrombus selectivity, including the use of specific antibodies for targeting thrombi. We discuss particulate carrier-based systems and triggered-release concepts. We propose new hypotheses and strategies to spur future studies in this research arena. Overall, we describe the approaches and accomplishments in the development of patient-friendly and workable delivery systems for thrombolytic drugs. PMID:26074048

  9. Management of inferior vena cava tumor thrombus in locally advanced renal cell carcinoma

    PubMed Central

    Psutka, Sarah P.

    2015-01-01

    The diagnosis of renal cell carcinoma is accompanied by intravascular tumor thrombus in up to 10% of cases, of which nearly one-third of patients also have concurrent metastatic disease. Surgical resection in the form of radical nephrectomy and caval thrombectomy represents the only option to obtain local control of the disease and is associated with durable oncologic control in approximately half of these patients. The objective of this clinical review is to outline the preoperative evaluation for, and operative management of patients with locally advanced renal cell carcinoma with venous tumor thrombi involving the inferior vena cava. Cornerstones of the management of these complex patients include obtaining high-quality imaging to characterize the renal mass and tumor thrombus preoperatively, with further intraoperative real-time evaluation using transesophageal echocardiography, careful surgical planning, and a multidisciplinary approach. Operative management of patients with high-level caval thrombi should be undertaken in high-volume centers by surgical teams with capacity for bypass and invasive intraoperative monitoring. In patients with metastatic disease at presentation, cytoreductive nephrectomy and tumor thrombectomy may be safely performed with simultaneous metastasectomy if possible. In the absence of level one evidence, neoadjuvant targeted therapy should continue to be viewed as experimental and should be employed under the auspices of a clinical trial. However, in patients with significant risk factors for postoperative complications and mortality, and especially in those with metastatic disease, consultation with medical oncology and frontline targeted therapy may be considered. PMID:26445601

  10. Single Photon Emission Computed Tomography-Based Three-Dimensional Conformal Radiotherapy for Hepatocellular Carcinoma With Portal Vein Tumor Thrombus

    SciTech Connect

    Shirai, Shintaro; Sato, Morio Suwa, Kazuhiro; Kishi, Kazushi; Shimono, Chigusa; Kawai, Nobuyuki; Tanihata, Hirohiko; Minamiguchi, Hiroki; Nakai, Motoki

    2009-03-01

    Purpose: To evaluate the safety and efficacy of three-dimensional conformal radiotherapy (3D-CRT) using single photon emission computed tomography (SPECT) in unresectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Methods and Materials: Patients with HCC with PVTT in the first branch and/or main trunk were selected for this study. The optimal beam directions for 3D-CRT were explored using a Tc-99m-galactosyl human serum albumin SPECT image for guidance. The SPECT image was classified as either wedge type or localized type. The clinical target volume to a total dose of 45 or 50 Gy per 18-20 fractions included the main tumor and PVTT in the wedge type and PVTT alone in the localized type. Results: Twenty-six patients were enrolled: 18 with wedge type and 8 with localized type. Mean tumor size was 7.1 cm (range, 4.4-12.3 cm). Clinical target volumes of wedge type vs. localized type were 111.2 cm{sup 3} vs. 48.4 cm{sup 3} (p = 0.010), respectively. Mean dose to normal liver and mean dose to functional liver were 1185 cGy and 988 cGy (p = 0.001) in wedge type and 1046 cGy and 1043 cGy (p = 0.658) in localized type, respectively. Despite an incidence of Child-Pugh B and C of 57.7%, no patients experienced radiation-induced liver disease. The progression of PVTT was inhibited, with an incidence of 92.2%; survival rates at 1 and 2 years were 44% and 30%, respectively. Conclusion: Single photon emission computed tomography-based 3D-CRT enables irradiation of both the main tumor and PVTT with low toxicity and promising survival.

  11. Nanosecond pulse electric field activation of platelet-rich plasma reduces myocardial infarct size and improves left ventricular mechanical function in the rabbit heart.

    PubMed

    Hargrave, Barbara; Li, Francis

    2012-12-01

    In the current study, we used the novel, nonchemical method of nanosecond pulsed electric fields (nsPEF) to investigate the efficiency of a protocol involving the in vivo treatment of the ischemic and reperfused heart and heart cells in culture with platelet-rich plasma (PRP). Associated with the restoration of blood flow to the ischemic tissue is a phenomenon referred to as "ischemic reperfusion injury." Clinically a type of reperfusion injury occurs during coronary bypass surgery once blood perfusion to the heart is restarted. Although the restoration of oxygen to ischemic myocardial cells is critical for tissue survival, reperfusion causes myocardial oxidative stress, attributable in part to the increased production of reactive oxygen species (ROS). Enhanced ROS production is associated with mitochondrial damage. Adult female New Zealand white rabbits were anesthetized and a left thoracotomy performed to expose the heart. The distal segment of the left anterior descending coronary artery was occluded for 15 minutes and then released so reperfusion of the tissue could occur. PRP (.21 mg/heart) or saline was injected into the ischemic area of the myocardium. Mechanical function of the left ventricle was analyzed using a Millar catheter attached to a Micro-Med Analysis System. H9c2 cells in culture were treated with 1 mL of nsPEF activated PRP (1.05 mg/flask) for 24 hours before analysis for ROS production or mitochondrial depolarization damage). The left ventricle contracted and relaxed faster and infarct size was reduced in hearts treated with PRP compared with saline. ROS production and mitochondrial depolarization were reduced in H9c2 cells treated with PRP and stimulated with hydrogen peroxide. These results provide evidence that nsPEFs can successfully be used to prepare PRP and that the PRP is functional in heart protection possibly by reducing ROS generation and stabilizing the mitochondria of the ischemic/reperfused heart.

  12. Glial Restricted Precursor Cell Transplant with Cyclic Adenosine Monophosphate Improved Some Autonomic Functions but Resulted in a Reduced Graft Size after Spinal Cord Contusion Injury in Rats

    PubMed Central

    Nout, Yvette S.; Culp, Esther; Schmidt, Markus H.; Tovar, C. Amy; Pröschel, Christoph; Mayer-Pröschel, Margot; Noble, Mark D.; Beattie, Michael S.; Bresnahan, Jacqueline C.

    2010-01-01

    Transplantation of glial restricted precursor (GRP) cells has been shown to reduce glial scarring after spinal cord injury (SCI) and, in combination with neuronal restricted precursor (NRP) cells or enhanced expression of neurotrophins, to improve recovery of function after SCI. We hypothesized that combining GRP transplants with rolipram and cAMP would improve functional recovery, similar to that seen after combining Schwann cell transplants with increasing cAMP. A short term study, 1)uninjured control, 2)SCI+vehicle, and 3)SCI+cAMP, showed that spinal cord [cAMP] were increased 14 days after SCI. We used 51 male rats subjected to a thoracic SCI for a 12-week survival study: 1)SCI+vehicle, 2)SCI+GRP, 3)SCI+cAMP, 4)SCI+GRP+cAMP, and 5)uninjured endpoint age-matched control (AM). Rolipram was administered for 2 weeks after SCI. At 9 days after SCI, GRP transplantation and injection of dibutyryl-cAMP into the spinal cord were performed. GRP cells survived, differentiated, and formed extensive transplants that were well integrated with host tissue. Presence of GRP cells increased the amount of tissue in the lesion; however, cAMP reduced the graft size. White matter sparing at the lesion epicenter was not affected. Serotonergic input to the lumbosacral spinal cord was not affected by treatment, but the amount of serotonin immediately caudal to the lesion was reduced in the cAMP groups. Using telemetric monitoring of corpus spongiosum penis pressure we show that the cAMP groups regained the same number of micturitions per 24 hrs when compared to the AM group, however, the frequency of peak pressures was increased in these groups compared to the AM group. In contrast, the GRP groups had similar frequency of peak pressures compared to baseline and the AM group. Animals that received GRP cells regained the same number of erectile events per 24 hrs compared to baseline and the AM group. Since cAMP reduced the GRP transplant graft, and some modest positive effects were seen

  13. Effect of Thrombus Composition and Viscosity on Sonoreperfusion Efficacy in a Model of Micro-Vascular Obstruction.

    PubMed

    Black, John J; Yu, Francois T H; Schnatz, Rick G; Chen, Xucai; Villanueva, Flordeliza S; Pacella, John J

    2016-09-01

    Distal embolization of micro-thrombi during stenting for myocardial infarction causes micro-vascular obstruction (MVO). We have previously shown that sonoreperfusion (SRP), a microbubble (MB)-mediated ultrasound (US) therapy, resolves MVO from venous micro-thrombi in vitro in saline. However, blood is more viscous than saline, and arterial thrombi that embolize during stenting are mechanically distinct from venous clot. Therefore, we tested the hypothesis that MVO created with arterial micro-thrombi are more resistant to SRP therapy compared with venous micro-thrombi, and higher viscosity further increases the US requirement for effective SRP in an in vitro model of MVO. Lipid MBs suspended in plasma with adjusted viscosity (1.1 cP or 4.0 cP) were passed through tubing bearing a mesh with 40-μm pores to simulate a micro-vascular cross-section; upstream pressure reflected thrombus burden. To simulate MVO, the mesh was occluded with either arterial or venous micro-thrombi to increase upstream pressure to 40 mmHg ± 5 mmHg. Therapeutic long-tone-burst US was delivered to the occluded area for 20 min. MB activity was recorded with a passive cavitation detector. MVO caused by arterial micro-thrombi at either blood or plasma viscosity resulted in less effective SRP therapy compared to venous thrombi. Higher viscosity further reduced the effectiveness of SRP therapy. The passive cavitation detector showed a decrease in inertial cavitation when viscosity was increased, while stable cavitation was affected in a more complex manner. Overall, these data suggest that arterial thrombi may require higher acoustic pressure US than venous thrombi to achieve similar SRP efficacy; increased viscosity decreases SRP efficacy; and both inertial and stable cavitation are implicated in observed SRP efficacy. PMID:27207018

  14. Reduced Appendicular Lean Body Mass, Muscle Strength, and Size of Type II Muscle Fibers in Patients with Spondyloarthritis versus Healthy Controls: A Cross-Sectional Study

    PubMed Central

    2016-01-01

    Introduction. The purpose of this study was to investigate body composition, muscle function, and muscle morphology in patients with spondyloarthritis (SpA). Methods. Ten male SpA patients (mean ± SD age 39 ± 4.1 years) were compared with ten healthy controls matched for sex, age, body mass index, and self-reported level of physical exercise. Body composition was measured by dual energy X-ray absorptiometry. Musculus quadriceps femoris (QF) strength was assessed by maximal isometric contractions prior to test of muscular endurance. Magnetic resonance imaging of QF was used to measure muscle size and calculate specific muscle strength. Percutaneous needle biopsy samples were taken from m. vastus lateralis. Results. SpA patients presented with significantly lower appendicular lean body mass (LBM) (p = 0.02), but there was no difference in bone mineral density, fat mass, or total LBM. Absolute QF strength was significantly lower in SpA patients (p = 0.03) with a parallel trend for specific strength (p = 0.08). Biopsy samples from the SpA patients revealed significantly smaller cross-sectional area (CSA) of type II muscle fibers (p = 0.04), but no difference in CSA type I fibers. Conclusions. Results indicate that the presence of SpA disease is associated with reduced appendicular LBM, muscle strength, and type II fiber CSA.

  15. Reduced Appendicular Lean Body Mass, Muscle Strength, and Size of Type II Muscle Fibers in Patients with Spondyloarthritis versus Healthy Controls: A Cross-Sectional Study

    PubMed Central

    2016-01-01

    Introduction. The purpose of this study was to investigate body composition, muscle function, and muscle morphology in patients with spondyloarthritis (SpA). Methods. Ten male SpA patients (mean ± SD age 39 ± 4.1 years) were compared with ten healthy controls matched for sex, age, body mass index, and self-reported level of physical exercise. Body composition was measured by dual energy X-ray absorptiometry. Musculus quadriceps femoris (QF) strength was assessed by maximal isometric contractions prior to test of muscular endurance. Magnetic resonance imaging of QF was used to measure muscle size and calculate specific muscle strength. Percutaneous needle biopsy samples were taken from m. vastus lateralis. Results. SpA patients presented with significantly lower appendicular lean body mass (LBM) (p = 0.02), but there was no difference in bone mineral density, fat mass, or total LBM. Absolute QF strength was significantly lower in SpA patients (p = 0.03) with a parallel trend for specific strength (p = 0.08). Biopsy samples from the SpA patients revealed significantly smaller cross-sectional area (CSA) of type II muscle fibers (p = 0.04), but no difference in CSA type I fibers. Conclusions. Results indicate that the presence of SpA disease is associated with reduced appendicular LBM, muscle strength, and type II fiber CSA. PMID:27672678

  16. Rotigaptide (ZP123) prevents spontaneous ventricular arrhythmias and reduces infarct size during myocardial ischemia/reperfusion injury in open-chest dogs.

    PubMed

    Hennan, James K; Swillo, Robert E; Morgan, Gwen A; Keith, James C; Schaub, Robert G; Smith, Robert P; Feldman, Hal S; Haugan, Ketil; Kantrowitz, Joel; Wang, Phil J; Abu-Qare, Aqel; Butera, John; Larsen, Bjarne D; Crandall, David L

    2006-04-01

    The antiarrhythmic and cardioprotective effect of increasing gap junction intercellular communication during ischemia/reperfusion injury has not been studied. The antiarrhythmic peptide rotigaptide (previously ZP123), which maintains gap junction intercellular communication, was tested in dogs subjected to a 60-min coronary artery occlusion and 4 h of reperfusion. Rotigaptide was administered i.v. 10 min before reperfusion as a bolus + i.v. infusion at doses of 1 ng/kg bolus + 10 ng/kg/h infusion (n = 6), 10 ng/kg bolus + 100 ng/kg/h infusion (n = 5), 100 ng/kg bolus + 1000 ng/kg/h infusion (n = 8), 1000 ng/kg bolus + 10 mug/kg/h infusion (n = 6), and vehicle control (n = 5). Premature ventricular complexes (PVCs) were quantified during reperfusion. A series of four or more consecutive PVCs was defined as ventricular tachycardia (VT). The total incidence of VT was reduced significantly with the two highest doses of rotigaptide (20.3 +/- 10.9 and 4.3 +/- 4.1 events; p < 0.05) compared with controls (48.7 +/- 6.0). Total PVCs were reduced significantly from 25.1 +/- 4.2% in control animals to 11.0 +/- 4.4 and 1.7 +/- 1.3% after the two highest doses of rotigaptide. Infarct size, expressed as a percentage of the left ventricle, was reduced significantly from 13.2 +/- 1.9 in controls to 7.1 +/- 1.0 (p < 0.05) at the highest dose of rotigaptide. Ultrastructural evaluation revealed no differences in myocardial injury in the infarct area, area at risk, border zone, or normal zone in vehicle and rotigaptide-treated animals. However, rotigaptide did increase the presence of gap junctions in the area at risk (p = 0.022, Fisher's exact test). Rotigaptide had no effect on heart rate, blood pressure, heart rate-corrected QT interval, or left ventricular end-diastolic pressure. In conclusion, these results demonstrate that rotigaptide is a potent antiarrhythmic compound with cardioprotective effects and desirable safety.

  17. Direct thrombus aspiration using the Penumbra system for the treatment of pediatric intracranial dissection.

    PubMed

    Fujimoto, Motoaki; Tateshima, Satoshi; Ali, Latisha; Raychev, Radoslav; Vinuela, Fernando

    2013-11-01

    We describe a case of a 15-year-old girl who developed a spontaneous intracranial arterial dissection with distal middle cerebral artery (MCA) occlusions. From the digital subtraction angiography provided, the dissection flap appeared to originate at the internal carotid artery terminus with extension into the right M1 segment and occluding the right anterior cerebral artery, A1 segment. CT perfusion study showed salvageable tissue in the posterior MCA territory, including the motor cortex. In order to avoid further injury to the dissection, clot retrieval systems were not a treatment option. We therefore performed selective thrombus aspiration with the Penumbra system for the occluded central and precentral arteries distal to the non-occlusive dissecting lesion. Sufficient recanalization was achieved and the patient made a marked recovery. Although mechanical thrombectomy with the use of retrieval intracranial stent systems has demonstrated satisfactory recanalization rates, the aspiration methodology remains useful for patients with an accompanying proximal vascular lesion. PMID:23188785

  18. Direct thrombus aspiration using the Penumbra system for the treatment of pediatric intracranial dissection.

    PubMed

    Fujimoto, Motoaki; Tateshima, Satoshi; Ali, Latisha; Raychev, Radoslav; Vinuela, Fernando

    2013-11-01

    We describe a case of a 15-year-old girl who developed a spontaneous intracranial arterial dissection with distal middle cerebral artery (MCA) occlusions. From the digital subtraction angiography provided, the dissection flap appeared to originate at the internal carotid artery terminus with extension into the right M1 segment and occluding the right anterior cerebral artery, A1 segment. CT perfusion study showed salvageable tissue in the posterior MCA territory, including the motor cortex. In order to avoid further injury to the dissection, clot retrieval systems were not a treatment option. We therefore performed selective thrombus aspiration with the Penumbra system for the occluded central and precentral arteries distal to the non-occlusive dissecting lesion. Sufficient recanalization was achieved and the patient made a marked recovery. Although mechanical thrombectomy with the use of retrieval intracranial stent systems has demonstrated satisfactory recanalization rates, the aspiration methodology remains useful for patients with an accompanying proximal vascular lesion.

  19. Direct thrombus aspiration using the Penumbra system for the treatment of pediatric intracranial dissection.

    PubMed

    Fujimoto, Motoaki; Tateshima, Satoshi; Ali, Latisha; Raychev, Radoslav; Vinuela, Fernando

    2012-11-15

    We describe a case of a 15-year-old girl who developed a spontaneous intracranial arterial dissection with distal middle cerebral artery (MCA) occlusions. From the digital subtraction angiography provided, the dissection flap appeared to originate at the internal carotid artery terminus with extension into the right M1 segment and occluding the right anterior cerebral artery, A1 segment. CT perfusion study showed salvageable tissue in the posterior MCA territory, including the motor cortex. In order to avoid further injury to the dissection, clot retrieval systems were not a treatment option. We therefore performed selective thrombus aspiration with the Penumbra system for the occluded central and precentral arteries distal to the non-occlusive dissecting lesion. Sufficient recanalization was achieved and the patient made a marked recovery. Although mechanical thrombectomy with the use of retrieval intracranial stent systems has demonstrated satisfactory recanalization rates, the aspiration methodology remains useful for patients with an accompanying proximal vascular lesion.

  20. Cardiac thrombus with risk of fulminant pulmonary embolism in paediatric antiphospholipid syndrome.

    PubMed

    Albinski, M; Hufnagel, M; Schelling, J; Fleck, T; Siepe, M; Zieger, B; Stiller, B

    2016-07-01

    Antiphospholipid Syndrome (APS) describes a systemic disease caused by autoantibodies to membrane components. Involving coagulation pathways, complement factors and immune cells, it results in thrombosis in any blood vessel. Its clinical presentation varies considerably depending upon the organ affected. Paediatric data on APS remain sparse. Most case reports focus on catastrophic APS with multiple small-vessel occlusions and a life-threatening course. Here, we report on a 15-year-old patient with deep vein thrombosis and a right ventricular tumour posing the risk of a fulminant pulmonary embolism. The tumour was surgically removed. Histology revealed it to be a thrombus. The patient fully recovered and is currently treated with long term anticoagulation. PMID:27138626

  1. Effect of noise reducing components on nose landing gear stability for a mid-size aircraft coupled with vortex shedding and freeplay

    NASA Astrophysics Data System (ADS)

    Eret, Petr; Kennedy, John; Bennett, Gareth J.

    2015-10-01

    In the pursuit of quieter aircraft, significant effort has been dedicated to airframe noise identification and reduction. The landing gear is one of the main sources of airframe noise on approach. The addition of noise abatement technologies such as fairings or wheel hub caps is usually considered to be the simplest solution to reduce this noise. After touchdown, noise abatement components can potentially affect the inherently nonlinear and dynamically complex behaviour (shimmy) of landing gear. Moreover, fairings can influence the aerodynamic load on the system and interact with the mechanical freeplay in the torque link. This paper presents a numerical study of nose landing gear stability for a mid-size aircraft with low noise solutions, which are modelled by an increase of the relevant model structural parameters to address a hypothetical effect of additional fairings and wheel hub caps. The study shows that the wheel hub caps are not a threat to stability. A fairing has a destabilising effect due to the increased moment of inertia of the strut and a stabilising effect due to the increased torsional stiffness of the strut. As the torsional stiffness is dependent on the method of attachment, in situations where the fairing increases the torsional inertia with little increase to the torsional stiffness, a net destabilising effect can result. Alternatively, it is possible that for the case that if the fairing were to increase equally both the torsional stiffness and the moment of inertia of the strut, then their effects could be mutually negated. However, it has been found here that for small and simple fairings, typical of current landing gear noise abatement design, their implementation will not affect the dynamics and stability of the system in an operational range (Fz ≤ 50 000 N, V ≤ 100 m/s). This generalisation is strictly dependent on size and installation methods. The aerodynamic load, which would be influenced by the presence of fairings, was modelled

  2. Cooperative integrin/ITAM signaling in platelets enhances thrombus formation in vitro and in vivo

    PubMed Central

    Zhi, Huiying; Rauova, Lubica; Hayes, Vincent; Gao, Cunji; Boylan, Brian; Newman, Debra K.; McKenzie, Steven E.; Cooley, Brian C.; Poncz, Mortimer; Newman, Peter J.

    2013-01-01

    The integrin family is composed of a series of 24 αβ heterodimer transmembrane adhesion receptors that mediate cell-cell and cell-extracellular matrix interactions. Adaptor molecules bearing immunoreceptor tyrosine-based activation motifs (ITAMs) have recently been shown to cooperate with specific integrins to increase the efficiency of transmitting ligand-binding–induced signals into cells. In human platelets, Fc receptor γ-chain IIa (FcγRIIa) has been identified as an ITAM-bearing transmembrane receptor responsible for mediating “outside-in” signaling through αIIbβ3, the major adhesion receptor on the platelet surface. To explore the importance of FcγRIIa in thrombosis and hemostasis, we subjected FcγRIIa-negative and FcγRIIa-positive murine platelets to a number of well-accepted models of platelet function. Compared with their FcγRIIa-negative counterparts, FcγRIIa-positive platelets exhibited increased tyrosine phosphorylation of Syk and phospholipase Cγ2 and increased spreading upon interaction with immobilized fibrinogen, retracted a fibrin clot faster, and showed markedly enhanced thrombus formation when perfused over a collagen-coated flow chamber under conditions of arterial and venous shear. They also displayed increased thrombus formation and fibrin deposition in in vivo models of vascular injury. Taken together, these data establish FcγRIIa as a physiologically important functional conduit for αIIbβ3-mediated outside-in signaling, and suggest that modulating the activity of this novel integrin/ITAM pair might be effective in controlling thrombosis. PMID:23264598

  3. Glaucocalyxin A inhibits platelet activation and thrombus formation preferentially via GPVI signaling pathway.

    PubMed

    Li, Wei; Tang, Xiaorong; Yi, Wenxiu; Li, Qiang; Ren, Lijie; Liu, Xiaohui; Chu, Chunjun; Ozaki, Yukio; Zhang, Jian; Zhu, Li

    2013-01-01

    Platelets play a pivotal role in atherothrombosis and the antiplatelet agents have been proved to be useful in preventing onset of acute clinical events including myocardial infarction and stroke. Increasing number of natural compounds has been identified to be potential antiplatelet agents. Here we report the antiplatelet effect of glaucocalyxin A (GLA), an ent-diterpenoid that we isolated and purified from the aerial parts of Rabdosia japonica (Burm. f.) var. glaucocalyx (Maxim.) Hara, and investigate the molecular mechanisms by which GLA inhibits platelet activation and thrombus formation. The effect of GLA on platelet activation was measured using platelets freshly isolated from peripheral blood of healthy donors. Results showed that pretreatment of human platelets with lower concentrations of GLA (0.01 μg/ml, 0.1 μg/ml) significantly inhibited platelet aggregation induced by collagen (P<0.001) and CRP (P<0.01), a synthetic GPVI ligand, but not by ADP and U46619. Accordingly, GLA inhibited collagen-stimulated tyrosine phosphorylation of Syk, LAT, and phospholipase Cγ2, the signaling events in collagen receptor GPⅥ pathway. GLA also inhibited platelet p-selectin secretion and integrin activation by convulxin, a GPVI selective ligand. Additionally, GLA was found to inhibit low-dose thrombin-induced platelet activation. Using a flow chamber device, GLA was found to attenuate platelet adhesion on collagen surfaces in high shear condition. In vivo studies showed that GLA administration increased the time for complete occlusion upon vascular injury in mice, but did not extend tail-bleeding time when mice were administered with relatively lower doses of GLA. Therefore, the present results provide the molecular basis for the inhibition effect of GLA on platelet activation and its in vivo effect on thrombus formation, suggesting that GLA could potentially be developed as an antiplatelet and antithrombotic agent. PMID:24386454

  4. Protective mechanisms of adenosine 5'-monophosphate in platelet activation and thrombus formation.

    PubMed

    Fuentes, E; Badimon, L; Caballero, J; Padró, T; Vilahur, G; Alarcón, M; Pérez, P; Palomo, I

    2014-03-01

    Platelet activation is relevant to a variety of acute thrombotic events. We sought to examine adenosine 5'-monophosphate (AMP) mechanisms of action in preventing platelet activation, thrombus formation and platelet-related inflammatory response. We assessed the effect of AMP on 1) P-selectin expression and GPIIb/IIIa activation by flow cytometry; 2) Platelet aggregation and ATP secretion induced by ADP, collagen, TRAP-6, convulxin and thrombin; 3) Platelet rolling and firm adhesion, and platelet-leukocyte interactions under flow-controlled conditions; and, 4) Platelet cAMP levels, sP-selectin, sCD40L, IL-1β, TGF-β1 and CCL5 release, PDE3A activity and PKA phosphorylation. The effect of AMP on in vivo thrombus formation was also evaluated in a murine model. The AMP docking with respect to A2 adenosine receptor was determined by homology. AMP concentration-dependently (0.1 to 3 mmol/l) inhibited P-selectin expression and GPIIb/IIIa activation, platelet secretion and aggregation induced by ADP, collagen, TRAP-6 and convulxin, and diminished platelet rolling and firm adhesion. Furthermore, AMP induced a marked increase in the rolling speed of leukocytes retained on the platelet surface. At these concentrations AMP significantly decreased inflammatory mediator from platelet, increased intraplatelet cAMP levels and inhibited PDE3A activity. Interestingly, SQ22536, ZM241385 and SCH58261 attenuated the antiplatelet effect of AMP. Docking experiments revealed that AMP had the same orientation that adenosine inside the A2 adenosine receptor binding pocket. These in vitro antithrombotic properties were further supported in an in vivo model of thrombosis. Considering the successful use of combined antiplatelet therapy, AMP may be further developed as a novel antiplatelet agent. PMID:24306059

  5. The Use of Fluid Mechanics to Predict Regions of Microscopic Thrombus Formation in Pulsatile VADs.

    PubMed

    Topper, Stephen R; Navitsky, Michael A; Medvitz, Richard B; Paterson, Eric G; Siedlecki, Christopher A; Slattery, Margaret J; Deutsch, Steven; Rosenberg, Gerson; Manning, Keefe B

    2014-03-01

    We compare the velocity and shear obtained from particle image velocimetry (PIV) and computational fluid dynamics (CFD) in a pulsatile ventricular assist device (VAD) to further test our thrombus predictive methodology using microscopy data from an explanted VAD. To mimic physiological conditions in vitro, a mock circulatory loop is used with a blood analog that matched blood's viscoelastic behavior at 40% hematocrit. Under normal physiologic pressures and for a heart rate of 75 bpm, PIV data is acquired and wall shear maps are produced. The resolution of the PIV shear rate calculations are tested using the CFD and found to be in the same range. A bovine study, using a model of the 50 cc Penn State V-2 VAD, for 30 days at a constant beat rate of 75 beats per minute (bpm) provides the microscopic data whereby after the 30 days, the device is explanted and the sac surface analyzed using scanning electron microscopy (SEM) and, after immunofluorescent labeling for platelets and fibrin, confocal microscopy. Areas are examined based on PIV measurements and CFD, with special attention to low shear regions where platelet and fibrin deposition are most likely to occur. Data collected within the outlet port in a direction normal to the front wall of the VAD shows that some regions experience wall shear rates less than 500 s(-1), which increases the likelihood of platelet and fibrin deposition. Despite only one animal study, correlations between PIV, CFD, and in vivo data show promise. Deposition probability is quantified by the thrombus susceptibility potential, a calculation to correlate low shear and time of shear with deposition.

  6. Prime, Shock, and Kill: Priming CD4 T Cells from HIV Patients with a BCL-2 Antagonist before HIV Reactivation Reduces HIV Reservoir Size

    PubMed Central

    Cummins, Nathan W.; Sainski, Amy M.; Dai, Haiming; Natesampillai, Sekar; Pang, Yuan-Ping; Bren, Gary D.; de Araujo Correia, Maria Cristina Miranda; Sampath, Rahul; Rizza, Stacey A.; O'Brien, Daniel; Yao, Joseph D.

    2016-01-01

    proapoptotic effects. Antagonizing BCL-2 with venetoclax derepresses this antagonism, resulting in death, preferentially in HIV DNA containing cells, since only these cells generate Casp8p41. Thus, BCL-2 antagonism is a clinically relevant intervention with the potential to reduce HIV reservoir size in patients. PMID:26842479

  7. Beetroot juice reduces infarct size and improves cardiac function following ischemia–reperfusion injury: Possible involvement of endogenous H2S

    PubMed Central

    Salloum, Fadi N; Sturz, Gregory R; Yin, Chang; Rehman, Shabina; Hoke, Nicholas N; Kukreja, Rakesh C

    2015-01-01

    Ingestion of high dietary nitrate in the form of beetroot juice (BRJ) has been shown to exert antihypertensive effects in humans through increasing cyclic guanosine monophosphate (cGMP) levels. Since enhanced cGMP protects against myocardial ischemia–reperfusion (I/R) injury through upregulation of hydrogen sulfide (H2S), we tested the hypothesis that BRJ protects against I/R injury via H2S. Adult male CD-1 mice received either regular drinking water or those dissolved with BRJ powder (10 g/L, containing ∼0.7 mM nitrate). Seven days later, the hearts were explanted for molecular analyses. Subsets of mice were subjected to I/R injury by occlusion of the left coronary artery for 30 min and reperfusion for 24 h. A specific inhibitor of H2S producing enzyme – cystathionine-γ-lyase (CSE), dl-propargylglycine (PAG, 50 mg/kg) was given i.p. 30 min before ischemia. Myocardial infarct size was significantly reduced in BRJ-fed mice (15.8 ± 3.2%) versus controls (46.5 ± 3.5%, mean ± standard error [SE], n = 6/group, P < .05). PAG completely blocked the infarct-limiting effect of BRJ. Moreover, BRJ significantly preserved ventricular function following I/R. Myocardial levels of H2S and its putative protein target – vascular endothelial growth factor receptor 2 (VEGFR2) were significantly increased by BRJ intake, whereas CSE mRNA and protein content did not change. Interestingly, the BRJ-induced cardioprotection was not associated with elevated blood nitrate–nitrite levels following I/R nor induction of cardiac peroxiredoxin 5, a mitochondrial antioxidant enzyme previously linked to nitrate-induced cardioprotection. We conclude that BRJ ingestion protects against post-I/R myocardial infarction and ventricular dysfunction possibly through CSE-mediated endogenous H2S generation. BRJ could be a promising natural and inexpensive nutraceutical supplement to reduce cardiac I/R injury in patients. PMID:25361774

  8. Ablation of the cholesterol transporter adenosine triphosphate-binding cassette transporter G1 reduces adipose cell size and protects against diet-induced obesity.

    PubMed

    Buchmann, Jana; Meyer, Christoph; Neschen, Susanne; Augustin, Robert; Schmolz, Katja; Kluge, Reinhart; Al-Hasani, Hadi; Jürgens, Hella; Eulenberg, Karsten; Wehr, Roland; Dohrmann, Cord; Joost, Hans-Georg; Schürmann, Annette

    2007-04-01

    The ATP-binding cassette transporter G1 (ABCG1) catalyzes export of cellular cholesterol from macrophages and hepatocytes. Here we identify an additional function of ABCG1 in the regulation of adiposity in screens of the Drosophila melanogaster and the New Zealand obese (NZO) mouse genomes. Insertion of modified transposable elements of the P-family upstream of CG17646, the Drosophila ortholog of Abcg1, generated lines of flies with increased triglyceride stores. In NZO mice, an Abcg1 variant was identified in a suggestive adiposity quantitative trait locus and was associated with higher expression of the gene in white adipose tissue. Targeted disruption of Abcg1 in mice resulted in reduced body weight gain (8.42+/-0.6 g in Abcg1-/- vs. 13.07+/-1.1 g in Abcg1+/+ mice) and adipose tissue mass gain (3.78+/-1.3 g in Abcg1-/- vs. 9.39+/-1.6 g in Abcg1+/+ mice) detected over a period of 12 wk. The reduction of adipose tissue mass in Abcg1-/- mice was associated with markedly decreased size of the adipocytes. In contrast to their wild-type littermates, male Abcg1-/- mice exhibited no high-fat diet-induced impairment of glucose tolerance and fatty liver. Furthermore, Abcg1-/- mice possess decreased food intake and elevated total energy expenditure (Abcg1-/- mice, 748.1+/-5.4 kJ/kg metabolic body mass; Abcg1+/+ mice, 684.3+/-5.0 kJ/kg metabolic body mass; P=0.011), body temperature (Abcg1-/- mice, 37.82+/-0.29 C; Abcg1+/+ mice, 36.83+/-0.24 C; P<0.05), and locomotor activity (Abcg1-/- mice, 3655+/-189 counts/12 h during dark phase; Abcg1+/+ mice, 2445+/-235 counts/12 h during dark phase; P<0.01). Our data indicate a previously unrecognized role of ABCG1 in the regulation of energy balance and triglyceride storage.

  9. Competitive fitness in coronaviruses is not correlated with size or number of double-membrane vesicles under reduced-temperature growth conditions.

    PubMed

    Al-Mulla, Hawaa M N; Turrell, Lauren; Smith, Nicola M; Payne, Luke; Baliji, Surendranath; Züst, Roland; Thiel, Volker; Baker, Susan C; Siddell, Stuart G; Neuman, Benjamin W

    2014-01-01

    Positive-stranded viruses synthesize their RNA in membrane-bound organelles, but it is not clear how this benefits the virus or the host. For coronaviruses, these organelles take the form of double-membrane vesicles (DMVs) interconnected by a convoluted membrane network. We used electron microscopy to identify murine coronaviruses with mutations in nsp3 and nsp14 that replicated normally while producing only half the normal amount of DMVs under low-temperature growth conditions. Viruses with mutations in nsp5 and nsp16 produced small DMVs but also replicated normally. Quantitative reverse transcriptase PCR (RT-PCR) confirmed that the most strongly affected of these, the nsp3 mutant, produced more viral RNA than wild-type virus. Competitive growth assays were carried out in both continuous and primary cells to better understand the contribution of DMVs to viral fitness. Surprisingly, several viruses that produced fewer or smaller DMVs showed a higher fitness than wild-type virus at the reduced temperature, suggesting that larger and more numerous DMVs do not necessarily confer a competitive advantage in primary or continuous cell culture. For the first time, this directly demonstrates that replication and organelle formation may be, at least in part, studied separately during infection with positive-stranded RNA virus. IMPORTANCE The viruses that cause severe acute respiratory syndrome (SARS), poliomyelitis, and hepatitis C all replicate in double-membrane vesicles (DMVs). The big question about DMVs is why they exist in the first place. In this study, we looked at thousands of infected cells and identified two coronavirus mutants that made half as many organelles as normal and two others that made typical numbers but smaller organelles. Despite differences in DMV size and number, all four mutants replicated as efficiently as wild-type virus. To better understand the relative importance of replicative organelles, we carried out competitive fitness experiments. None

  10. [Outcome of Resection of Inferior Vena Cava Superior to the Renal Vein in Renal Cell Carcinoma with Vena Caval Tumor Thrombus].

    PubMed

    Kashima, Soki; Narita, Shintaro; Saito, Mitsuru; Takahashi, Makoto; Maita, Shinya; Tsuruta, Hiroshi; Numakura, Kazuyuki; Maeno, Atsushi; Inoue, Takamitsu; Tsuchiya, Norihiko; Satoh, Shigeru; Yamamoto, Hiroshi; Yamamoto, Yuzo; Habuchi, Tomonori

    2016-06-01

    Surgical management with radical nephrectomy and thrombectomy has often been performed in renal cell carcinoma (RCC) with tumor thrombus infiltrating the inferior vena cava (IVC). We retrospectively reviewed the outcomes of IVC resection without venous reconstruction in patients with RCC and IVC thrombus at our institution. Eight patients with right RCC underwent radical nephrectomy and IVC resection superior to the level of the renal vein without venous reconstruction from August 2005 to February 2015. Thoracotomy, liver mobilization, and extracorporeal circulation were performed based on the IVC thrombus level. We assessed surgical outcomes, perioperative complications, and survival. At presentation, four patients had level IIIa IVC thrombus, three had level IIIb IVC thrombus, and one had level IV IVC thrombus. Perioperative imaging showed that three of the four patients who underwent neoadjuvant molecular targeting therapy achieved down-staging of the tumor thrombus level. The median operative time was 406 min, and the median estimated blood loss was 3,135 ml. With regard to IVC resectionassociated perioperative complications, one patient needed extracorporeal circulation with IVC ligation and Pringle maneuver owing to low blood pressure. Another patient underwent temporary hemodialysis for 8 days after surgery. There were no perioperative deaths, and none of the patients required permanent hemodialysis. Three patients survived the mean observation period of 25 months, including one patient with no recurrence. Three patients achieved long-term survival of more than 2 years. IVC resection without venous reconstruction may be a feasible option for patients with RCC and IVC tumor thrombus. Further study is needed to determine the most appropriate candidates for this procedure. PMID:27452491

  11. Free-floating thrombus of the carotid artery with a homozygous methylenetetrahydrofolate reductase gene mutation: a case report.

    PubMed

    Colak, Necmettin; Nazli, Yunus; Kosehan, Dilek; Alpay, Mehmet Fatih; Cakir, Omer

    2013-02-01

    Free-floating thrombus (FFT) of the carotid artery is a rare condition of currently unknown etiology. We describe a symptomatic patient with an FFT in the left common carotid artery. A duplex ultrasonography scan showed the presence of a mobile floating thrombus moving in cyclical motion with the cardiac cycles in the left common carotid artery. During emergency surgery, an FFT was seen at this location and removed. No underlying wall defect was seen at the time of surgery. In a genetic screening test, TT homozygous for the methylenetetrahydrofolate reductase (MTHFR) C677T genetic polymorphisms was detected. The patient recovered uneventfully, with no neurogical events. Lifelong anticoagulant therapy was recommended. An aggressive surgical approach is recommended in the patient to prevent embolic episodes. PMID:22101856

  12. Massive renal urothelial carcinoma with renal vein tumor thrombus, pancreatic infiltration and adrenal metastasis: A case report

    PubMed Central

    Li, Tao; Gao, Liang; Wu, Weilu; Chen, Peng; Bu, Siyuan; Wei, Qiang; Yang, Lu

    2016-01-01

    A 49-year-old female patient presented with a massive left renal tumor, recurrent left flank pain and gross hematuria. The tumor was accompanied by a renal vein tumor thrombus, pancreatic infiltration and a solitary adrenal metastasis. Radical nephrectomy, distal pancreatectomy, ipsilateral adrenalectomy and splenectomy were performed. Histopathological examination suggested high-grade urothelial carcinoma (UC); however, tumor recurrence and multiple metastases were detected only 3 months after the surgery, and the patient succumbed during follow-up 1 month later. To the best of our knowledge, this is the first case of renal UC of such advanced stage with renal vein tumor thrombus, pancreatic infiltration and a solitary adrenal metastasis. PMID:27446406

  13. ANCA-negative eosinophilic granulomatosis with polyangitis (EGPA) manifesting as a large intracardiac thrombus and glomerulonephritis with angionecrosis.

    PubMed

    Saito, Yuichi; Okada, Sho; Funabashi, Nobusada; Kobayashi, Yoshio

    2016-01-01

    A 59-year-old woman with a history of bronchial asthma presented with a prolonged fever and eosinophilia. There was transient proteinuria and troponin level was elevated. Antineutrophil cytoplasmic antibody was negative and she did not fulfil criteria for eosinophilic granulomatosis with polyangitis (EGPA). Echocardiography showed a large apical mass in the left ventricle, but there was no systolic dysfunction, local asynergy or ventricular remodelling. On MRI, apical mass was compatible with a thrombus and endocardial region was diffusely damaged. Loeffler endocarditis-like cardiac manifestation led to meticulous examination, which found no aetiology for eosinophilia. Finally, renal biopsy revealed eosinophil infiltration and glomerular angionecrosis, confirming as EGPA. This case highlights the isolated large cardiac thrombus as a rare presenting sign for EGPA and underscores current complicated strategy to diagnose EGPA. Of note, this clinical challenge was mostly caused by inchoate comprehension of hypereosinophilia-related disorders. PMID:27591039

  14. An Atypically Large, Free-Floating Thrombus Extending From the Lung to the Left Atrium via a Pulmonary Vein

    PubMed Central

    Wang, Wei; Li, Xuechang; Song, Weian; Zhang, Yunshan; Yue, Caiying; Shang, Liqun; Li, Jun; Wen, Feng; Liu, Junqiang; Zha, Peng

    2015-01-01

    Abstract An atypically large, free-floating thrombus extending from primary pulmonary malignancy into the left atrium (LA) is a rare phenomenon. Here, we report a 61-year-old man presenting with a large mass in the lower lobe of the left lung, extending to LA via the left inferior pulmonary vein. The thrombus remained clinically silent and was detected by computed tomography (CT) and transthoracic echocardiography. To prevent life-threatening complications including systemic embolism and sudden death, the patient underwent surgical excision of the mass under cardiopulmonary bypass. Pathology of the tumor and the embolus was confirmed as moderately differentiated squamous cell carcinoma. Furthermore, immunohistochemical studies demonstrated consistency of the tumor cells in this pathological category. The patient tolerated the surgery well and his condition began to improve gradually after the operation. PMID:26579798

  15. Vascular Smooth Muscle Cells Stimulate Platelets and Facilitate Thrombus Formation through Platelet CLEC-2: Implications in Atherothrombosis.

    PubMed

    Inoue, Osamu; Hokamura, Kazuya; Shirai, Toshiaki; Osada, Makoto; Tsukiji, Nagaharu; Hatakeyama, Kinta; Umemura, Kazuo; Asada, Yujiro; Suzuki-Inoue, Katsue; Ozaki, Yukio

    2015-01-01

    The platelet receptor CLEC-2 is involved in thrombosis/hemostasis, but its ligand, podoplanin, is expressed only in advanced atherosclerotic lesions. We investigated CLEC-2 ligands in vessel walls. Recombinant CLEC-2 bound to early atherosclerotic lesions and normal arterial walls, co-localizing with vascular smooth muscle cells (VSMCs). Flow cytometry and immunocytochemistry showed that recombinant CLEC-2, but not an anti-podoplanin antibody, bound to VSMCs, suggesting that CLEC-2 ligands other than podoplanin are present in VSMCs. VSMCs stimulated platelet granule release and supported thrombus formation under flow, dependent on CLEC-2. The time to occlusion in a FeCl3-induced animal thrombosis model was significantly prolonged in the absence of CLEC-2. Because the internal elastic lamina was lacerated in our FeCl3-induced model, we assume that the interaction between CLEC-2 and its ligands in VSMCs induces thrombus formation. Protein arrays and Biacore analysis were used to identify S100A13 as a CLEC-2 ligand in VSMCs. However, S100A13 is not responsible for the above-described VSMC-induced platelet activation, because S100A13 is not expressed on the surface of normal VSMCs. S100A13 was released upon oxidative stress and expressed in the luminal area of atherosclerotic lesions. Suspended S100A13 did not activate platelets, but immobilized S100A13 significantly increased thrombus formation on collagen-coated surfaces. Taken together, we proposed that VSMCs stimulate platelets through CLEC-2, possibly leading to thrombus formation after plaque erosion and stent implantation, where VSMCs are exposed to blood flow. Furthermore, we identified S100A13 as one of the ligands on VSMCs. PMID:26418160

  16. Effects of Endothelial Injury on the Rate of Thrombus Organization in Canine Carotid Arteries Occluded with Microcoils

    PubMed Central

    Abruzzo, T.; Shengelaia, G.G.; Workman, M.; Cloft, H.J.; Miller, D.A.; Dion, J.E.

    2003-01-01

    Summary Thrombus organization in canine carotid arteries occluded with platinum microcoils was studied to determine if endothelial injury created with a Xenon Chloride Excimer Laser (XEL) could acclerate endovascular fibrosis. Ten common carotid artery stumps were created in ten dogs. Each of four stumps were schematically divided into four longitudinally contiguous injury zones (thermal ablation injury, non-ablative injury, proximal and distal non-injury zones) to test the effects of ablative and non-ablative injury and to establish a set of internal controls that would account for proximity to circulating blood at the ostium of the occluded artery. Following XEL irradiation of the endothelium through an arteriotomy, each stump was embolized with microcoils. Four control stumps were subjected to sham laser procedures, and embolized in an identical fashion. Two additional stumps were embolized in the absence of sham surgery. Angiographic, gross and histologic analysis was performed after four weeks. Specimens of freshly clotted whole blood mixed with microcoils were used as an additional control. In irradiated stumps and non-irradiated stumps (sham and embolization only), angiography revealed no evidence of coil compaction or recanalization. In all irradiated stumps the thermal ablation zone contained fibrous tissue and neovascularity without unorganized thrombus. The other zones in the irradiated stumps were indistingnishable from each other and from all zones in the non-irradiated sham stumps, containing primarily unorganized thrombus. Stumps embolized in the absence of sham surgery were filled with material that was grossly and microscopically identical to specimens of freshly clotted whole blood containing microcoils. The results indicate that thermal ablation injury of the endothelium accelerates thrombus organization in canine carotid arteries occluded with platinum microcoils. PMID:20591298

  17. Thrombembolic occlusion of crural arteries following transcatheter aortic valve implantation--successful endovascular recanalization using a thrombus aspiration device.

    PubMed

    Malyar, Nasser M; Kaleschke, Gerrit; Reinecke, Holger

    2012-05-01

    Transcatheter aortic valve implantation (TAVI) has become an increasingly used alternative to conventional surgical valve replacement in patients with severe aortic valve stenosis (AS) and high operative risk. We here describe a case of a TAVI performed in local anesthesia causing intraprocedural thromboembolic occlusion of non-stenotic crural arteries and its immediate successful therapeutic management by means of endovascular recanalization using a thrombus aspiration device. PMID:22565625

  18. Ectonucleotide Triphosphate Diphosphohydrolase-1 (CD39) Mediates Resistance to Occlusive Arterial Thrombus Formation after Vascular Injury in Mice

    PubMed Central

    Huttinger, Zachary M.; Milks, Michael W.; Nickoli, Michael S.; Aurand, William L.; Long, Lawrence C.; Wheeler, Debra G.; Dwyer, Karen M.; d'Apice, Anthony J.F.; Robson, Simon C.; Cowan, Peter J.; Gumina, Richard J.

    2013-01-01

    Modulation of purinergic signaling, which is critical for vascular homeostasis and the response to vascular injury, is regulated by hydrolysis of proinflammatory ATP and/or ADP by ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) to AMP, which then is hydrolyzed by ecto-5′-nucleotidase (CD73) to adenosine. We report here that compared with littermate controls (wild type), transgenic mice expressing human ENTPDase-1 were resistant to the formation of an occlusive thrombus after FeCl3-induced carotid artery injury. Treatment of mice with the nonhydrolyzable ADP analog, adenosine-5′-0-(2-thiodiphosphate) trilithium salt, Ado-5′-PP[S], negated the protection from thrombosis, consistent with a role for ADP in platelet recruitment and thrombus formation. ENTPD-1 expression decreased whole-blood aggregation after stimulation by ADP, an effect negated by adenosine-5′-0-(2-thiodiphosphate) trilithium salt, Ado-5′-PP[S] stimulation, and limited the ability to maintain the platelet fibrinogen receptor, glycoprotein αIIb/β3, in a fully activated state, which is critical for thrombus formation. In vivo treatment with a CD73 antagonist, a nonselective adenosine-receptor antagonist, or a selective A2A or A2B adenosine-receptor antagonist, negated the resistance to thrombosis in transgenic mice expressing human ENTPD-1, suggesting a role for adenosine generation and engagement of adenosine receptors in conferring in vivo resistance to occlusive thrombosis in this model. In summary, our findings identify ENTPDase-1 modulation of purinergic signaling as a key determinant of the formation of an occlusive thrombus after vascular injury. PMID:22613024

  19. Dynamic monitoring of platelet deposition on severely damaged vessel wall in flowing blood. Effects of different stenoses on thrombus growth

    SciTech Connect

    Lassila, R.; Badimon, J.J.; Vallabhajosula, S.; Badimon, L. )

    1990-03-01

    The formation of an arterial thrombus is a dynamic process that depends upon the characteristics of blood flow, the triggering substrate, and the blood components. We have developed and characterized a sensitive and specific computer-assisted nuclear scintigraphic method to study the dynamics of platelet deposition on severely damaged vessels both in vitro and in vivo in nonstenotic and stenotic flow conditions. Heparinized pig blood with Indium-111-labeled platelets was perfused for 50 minutes. Method variability in both static and flowing conditions was evaluated by Indium-111-labeled transferrin and Indium-111-labeled platelets. Positive scintigrams were obtained mainly in the presence of severe high grade stenoses on a thrombogenic substrate. Since the method is highly sensitive, computer-assisted axial dependence analysis was performed on the scintigraphic images to locate the thrombotic accumulation with respect to the area of the stenosis and to monitor the dynamic changes in platelet accumulation over time. Both in vitro and in vivo the highest level of platelet deposition occurred at the apex of the 80% stenosis, where embolization could be usually detected after 30 minutes of perfusion. This study is the first to assess the dynamics of thrombus growth in nonparallel flow streamlines such as are encountered in stenotic vessels. This method provides a new experimental tool with which to study factors affecting thrombus formation and stability.

  20. [Initial division of the left renal vein before dissection of left renal vein occluded by intracaval tumor thrombus].

    PubMed

    Kurosawa, Kazuhiro; Okita, Ryuji; Motoshima, Takanobu; Fujioka, Masashi; Abe, Hiromitsu; Morikawa, Hirofumi; Okaneya, Toshikazu; Komatsu, Hideki

    2011-09-01

    Between November 2008 and March 2010, we performed initial division of the left renal vein occluded by the tumor thrombus in six cases of left renal cancer at Toranomon Hospital. The left renal vein was completely occluded by the tumor thrombus in all cases. In order to ligate the left renal artery first behind the dilated left renal vein, we must dissect the left kidney with arterial blood flow. Massive bleeding from the numerous engorged collateral veins around the left kidney is inevitable. Furthermore, access to the left renal artery is difficult because of the large tumor. We therefore initially divided the left renal vein without arterial blood flow followed by division of the left renal artery. After nephrectomy by dissecting the tumor without blood flow we extirpated the intracaval tumor thrombus. The median time of the operation was 7 hours 35 minutes and the median amount of blood loss was 2,869 ml. The tumor stage was pT3b in four cases and pT3c in two cases. No complications were observed during and after surgery except for one case of lymphocele and another case of chylous ascites. The initial division of the left renal vein is considered to be a useful surgical approach in left renal cancer with occluded left renal vein, especially when the tumor is large.

  1. Behçet’s disease presenting with Budd–Chiari syndrome and intracardial thrombus: a case report

    PubMed Central

    Kim, Minji Jennifer; Jo, Yong Suk; Kim, Jee Hyun; Kim, Yong-Jin; Kim, Kyung Hwan; Lee, Eun Bong; Song, Yeong Wook; Lee, Eun Young

    2011-01-01

    Budd–Chiari syndrome has been described as a late complication of Behçet’s disease. Although the mortality rate associated with Behçet’s disease is low, it can escalate in the presence of Budd–Chiari syndrome and may be further complicated by intracardial thrombus formation. It is therefore important to detect and initiate management early in the disease course. The imaging modalities of choice should be minimally invasive as certain procedures may aggravate Behçet’s disease by initiating a thrombosis or aggravating an existing one. In Behçet’s disease-induced Budd–Chiari syndrome, cardiac investigation is crucial in the work-up in order to identify any cardiac involvement and determine the etiology of intracardial thrombus. Furthermore, the treatment should ultimately focus on controlling the activity of Behçet’s disease. We report an unusual case of Behçet’s disease presenting with Budd–Chiari syndrome complicated by intracardial thrombus in a young Korean man. PMID:23754909

  2. A novel approach for assessing the progression of deep venous thrombosis by area of venous thrombus in ultrasonic elastography.

    PubMed

    Wang, Chao; Wang, Lei; Zhang, Yuhui; Chen, Ming

    2014-04-01

    Exact age determination of deep venous thrombosis (DVT) is important for an appropriate treatment. The purpose of this present study is to assess the age of acute DVT with the area of venous thrombi in elasticity imaging during the thrombosis procession. The thrombus area is obtained from a specially designed program. It was applied to clot specimens induced in human great saphenous (n = 15) at selected time points following the initiation of thrombosis. The relative mean proportion of blood clots was 50.01% ± 12.44% at day 1; 69.94% ± 8.19% at day 3; 81.93% ± 6.15% at day 6; and 92.37% ± 4.06% at day 9. The results indicated that the thrombus area increased significantly over time, while the normalized strain values inside the thrombus changed only a little. The pathological analyses also showed the same results. Therefore, we conclude that the area of venous thrombi in elasticity imaging may be a novel function for acute DVT staging.

  3. Effect of Metabolic Syndrome on Risk Stratification for Left Atrial or Left Atrial Appendage Thrombus Formation in Patients with Nonvalvular Atrial Fibrillation

    PubMed Central

    Chen, Yu-Yang; Liu, Qi; Liu, Li; Shu, Xiao-Rong; Su, Zi-Zhuo; Zhang, Hai-Feng; Nie, Ru-Qiong; Wang, Jing-Feng; Xie, Shuang-Lun

    2016-01-01

    Background: Metabolic syndrome (MS) is a risk factor for stroke and thromboembolism event. Left atrial or LA appendage (LA/LAA) thrombus is a surrogate of potential stroke. The relationship between MS and atrial thrombus remains unclear. In this study, we sought to investigate the effect of MS on risk stratification of LA/LAA thrombus formation in patients with nonvalvular atrial fibrillation (NVAF). Methods: This cross-sectional study enrolled 294 consecutive NVAF patients without prior anticoagulant and lipid-lowering therapies. LA/LAA thrombus was determined by transesophageal echocardiography. Risk assessment of LA/LAA thrombus was performed using the CHADS2, CHA2DS2-VASc, MS, CHADS2-MS, and CHA2DS2-VASc-MS scores. Logistic regression analyses were performed to determine which factors were significantly related to LA/LAA thrombus. Odds ratio (OR) including 95% confidence interval was also calculated. The predictive powers of different scores for the risk of LA/LAA thrombus were represented by C-statistics and compared by receiver operating characteristic (ROC) analysis. Results: LA/LAA thrombi were identified in 56 patients (19.0%). Logistic analysis showed that MS was the strongest risk factor for LA/LAA thrombus in NVAF patients (OR = 14.698, P < 0.001). ROC curve analyses revealed that the C-statistics of CHADS2-MS and CHA2DS2-VASc-MS was significantly higher than those of CHADS2 and CHA2DS2-VASc scores (CHADS2-MS vs. CHADS2, 0.807 vs. 0.726, P = 0.0019). Furthermore, MS was helpful for identifying individuals with a high risk of LA/LAA thrombus in the population with a low risk of stroke (CHADS2 or CHA2DS2-VASc score = 0). Conclusions: MS is associated with LA/LAA thrombus risk in patients with NVAF. In addition to the CHADS2 and CHA2DS2-VASc scores, the CHADS2-MS and CHA2DS2-VASc-MS scores provide additional information on stroke risk assessment. PMID:27748329

  4. Management of Primitive Neuroectodermal Tumor of the Kidney with Inferior Vena Cava Thrombus

    PubMed Central

    Gupta, Sahil; Majumder, Kaustav; Chahal, Anurag; Saini, Ashish K.; Gupta, Arjun

    2016-01-01

    Primitive neuroectodermal tumors (PNET) are an aggressive group of small round cell tumors usually arising in the nervous system and affecting children. They have a tendency for local invasion, distant spread and formation of tumor thrombi. The kidney is a rare primary location for these tumors. Outcomes are frequently poor due to late diagnosis (Wilms tumor is a more common tumor in this population) and early spread. Immunohistochemistry is invaluable in making the diagnosis of PNET. We report a case of a primary renal PNET with extensive tumor thrombus into the inferior vena cava, and lung metastasis in a pediatric patient, and its successful management. Our 14-year-old patient with renal PNET was managed with radical nephrectomy, thrombectomy and chemotherapy and remains disease free to date. The diagnosis of renal PNETs should be considered in young adult patients who present with aggressive renal masses at initial presentations. Despite its aggressive nature, good outcomes can be achieved by a multimodality therapeutic strategy. PMID:26989372

  5. Transarterial chemoembolization combined with sorafenib for the treatment of hepatocellular carcinoma with hepatic vein tumor thrombus

    PubMed Central

    Zhang, Yong-Fa; Wei, Wei; Wang, Jia-Hong; Xu, Li; Jian, Pei-En; Xiao, Cheng-Zuo; Zhong, Xiao-Ping; Shi, Ming; Guo, Rong-Ping

    2016-01-01

    Objective To compare the treatment outcomes of sorafenib plus transarterial chemoembolization (TACE) vs TACE alone in patients with hepatocellular carcinoma (HCC) and hepatic vein tumor thrombus (HVTT). Methods Twenty patients who were initially diagnosed with HCC and HVTT and received TACE combined with sorafenib during February 2009 to October 2013 were included in the study. To minimize selection bias, these patients were compared with 60 case-matched controls selected from a pool of 81 patients (in a 1:3 ratio) who received TACE alone during the same period. The primary end point was overall survival (OS). The secondary end points were time to progression, disease control rate, and adverse events. Results After a median follow-up period of 12.5 months (range, 1.03–44.23 months), the OS of the combined group was found to be significantly higher compared with the monotherapy group (14.9 vs 6.1 months, P=0.010). The time to progression was found to be significantly longer in the combined group (4.9 vs 2.4 months, P=0.016). Univariate and multivariate analyses revealed that the treatment allocation was an independent predictor of OS. Conclusion Sorafenib plus TACE was well tolerated and was more effective in treating patients with advanced HCC and HVTT. Future trials with prospective larger samples are required to validate these results. PMID:27471398

  6. Quantification of volume, mass, and density of thrombus formation using brightfield and differential interference contrast microscopy

    NASA Astrophysics Data System (ADS)

    Baker-Groberg, Sandra M.; Phillips, Kevin G.; McCarty, Owen J. T.

    2013-01-01

    Flow chamber assays, in which blood is perfused over surfaces of immobilized extracellular matrix proteins, are used to investigate the formation of platelet thrombi and aggregates under shear flow conditions. Elucidating the dynamic response of thrombi/aggregate formation to different coagulation pathway perturbations in vitro has been used to develop an understanding of normal and pathological cardiovascular states. Current microscopy techniques, such as differential interference contrast (DIC) or fluorescent confocal imaging, respectively, do not provide a simple, quantitative understanding of the basic physical features (volume, mass, and density) of platelet thrombi/aggregate structures. The use of two label-free imaging techniques applied, for the first time, to platelet aggregate and thrombus formation are introduced: noninterferometric quantitative phase microscopy, to determine mass, and Hilbert transform DIC microscopy, to perform volume measurements. Together these techniques enable a quantitative biophysical characterization of platelet aggregates and thrombi formed on three surfaces: fibrillar collagen, fibrillar collagen +0.1 nM tissue factor (TF), and fibrillar collagen +1 nM TF. It is demonstrated that label-free imaging techniques provide quantitative insight into the mechanisms by which thrombi and aggregates are formed in response to exposure to different combinations of procoagulant agonists under shear flow.

  7. Modelling of thrombus growth in flow with a DPD-PDE method.

    PubMed

    Tosenberger, A; Ataullakhanov, F; Bessonov, N; Panteleev, M; Tokarev, A; Volpert, V

    2013-11-21

    Hemostatic plug covering the injury site (or a thrombus in the pathological case) is formed due to the complex interaction of aggregating platelets with biochemical reactions in plasma that participate in blood coagulation. The mechanisms that control clot growth and which lead to growth arrest are not yet completely understood. We model them with numerical simulations based on a hybrid DPD-PDE model. Dissipative particle dynamics (DPD) is used to model plasma flow with platelets while fibrin concentration is described by a simplified reaction-diffusion-advection equation. The model takes into account consecutive stages of clot growth. First, a platelet is weakly connected to the clot and after some time this connection becomes stronger due to other surface receptors involved in platelet adhesion. At the same time, the fibrin mesh is formed inside the clot. This becomes possible because flow does not penetrate the clot and cannot wash out the reactants participating in blood coagulation. Platelets covered by the fibrin mesh cannot attach new platelets. Modelling shows that the growth of a hemostatic plug can stop as a result of its exterior part being removed by the flow thus exposing its non-adhesive core to the flow.

  8. Coupled Hemodynamic-Biochemical Modeling of Thrombus Formation in Infarcted Left Ventricles

    NASA Astrophysics Data System (ADS)

    Seo, Jung Hee; Vedula, Vijay; George, Richard; Mittal, Rajat

    2013-11-01

    Patients with heart failure (HF) and left ventricular (LV) systolic dysfunction have higher rates of thromboembolic events including embolic stroke and peripheral arterial thrombi. A common cause of arterial emboli in HF patients is myocardial infarction (MI) and subsequent left ventricular thrombus (LVT) formation. Stagnation of blood and endocardial injury are hypothesized to promote the development of LVT. The identification of high risk patients and the pharmacologic prevention of LVT formation are the keys to preventing embolic events. Stratification of patients at risk for LVT formation is currently limited, and primarily based on global assessment of ventricular function and image based assessment of ventricular wall motion. In this study, we explore a method to predict LVT risk using a multi-physics computational model. The blood flow in the left ventricle is simulated by solving the incompressible Navier-Stokes equation using an immersed boundary method and this is coupled to a convection-diffusion-reaction equation based model of platelet activation and coagulation. The results are then correlated with the other hemodynamic metrics such as wall shear stress and residence time to develop quantitative metrics for the LVT risk prediction. Supported by NSF CDI-Type II grant IOS-1124804, Computational resource by XSEDE NSF grant TG-CTS100002.

  9. Symptomatic Patients with Intraluminal Carotid Thrombus: Outcome with a Strategy of Initial Anticoagulation

    PubMed Central

    Vellimana, Ananth K.; Kadkhodayan, Yasha; Rich, Keith M.; Cross, Dewitte T.; Moran, Christopher J.; Zazulia, Allyson R.; Lee, Jin-Moo; Chicoine, Michael R.; Dacey, Ralph G.; Derdeyn, Colin P.; Zipfel, Gregory J.

    2013-01-01

    Background Optimal treatment for patients with symptomatic intraluminal carotid thrombus (ICT) remains poorly defined. Methods We performed a retrospective chart review of patients presenting to our institution between 2001 and 2011 with symptomatic ICT. Results Twenty-four patients (16 males, 8 females) with ICT presented with ischemic stroke (n=18) or TIA (n=6). All were treated initially with anticoagulation ± antiplatelet drugs. Eight of these patients had no or mild carotid stenosis on initial angiography and were treated with medical management alone. The remaining 16 patients had moderate or severe carotid stenosis on initial angiography. Of these, 10 underwent delayed revascularization (endarterectomy, n=8; angioplasty and stenting, n=2), 2 refused revascularization, and 4 were treated with medical therapy alone. One patient had multiple TIAs despite medical therapy and eventually underwent CEA; the remaining 23 patients had no TIAs. No patient suffered ischemic or hemorrhagic stroke while on anticoagulation, during the perioperative period or in long-term follow up; one patient died of an unrelated condition (mean follow-up = 16.4 months). Conclusion Our results suggest that initial anticoagulation of symptomatic ICT results in a low rate of recurrent ischemic events and that carotid revascularization, if indicated, can be safely performed in a delayed manner. PMID:23061393

  10. Parmodulins inhibit thrombus formation without inducing endothelial injury caused by vorapaxar

    PubMed Central

    Aisiku, Omozuanvbo; Peters, Christian G.; De Ceunynck, Karen; Ghosh, Chandra C.; Dilks, James R.; Fustolo-Gunnink, Susanna F.; Huang, Mingdong; Dockendorff, Chris; Parikh, Samir M.

    2015-01-01

    Protease-activated receptor-1 (PAR1) couples the coagulation cascade to platelet activation during myocardial infarction and to endothelial inflammation during sepsis. This receptor demonstrates marked signaling bias. Its activation by thrombin stimulates prothrombotic and proinflammatory signaling, whereas its activation by activated protein C (APC) stimulates cytoprotective and antiinflammatory signaling. A challenge in developing PAR1-targeted therapies is to inhibit detrimental signaling while sparing beneficial pathways. We now characterize a novel class of structurally unrelated small-molecule PAR1 antagonists, termed parmodulins, and compare the activity of these compounds to previously characterized compounds that act at the PAR1 ligand–binding site. We find that parmodulins target the cytoplasmic face of PAR1 without modifying the ligand-binding site, blocking signaling through Gαq but not Gα13 in vitro and thrombus formation in vivo. In endothelium, parmodulins inhibit prothrombotic and proinflammatory signaling without blocking APC-mediated pathways or inducing endothelial injury. In contrast, orthosteric PAR1 antagonists such as vorapaxar inhibit all signaling downstream of PAR1. Furthermore, exposure of endothelial cells to nanomolar concentrations of vorapaxar induces endothelial cell barrier dysfunction and apoptosis. These studies demonstrate how functionally selective antagonism can be achieved by targeting the cytoplasmic face of a G-protein–coupled receptor to selectively block pathologic signaling while preserving cytoprotective pathways. PMID:25587041

  11. Magnetic resonance direct thrombus imaging differentiates acute recurrent ipsilateral deep vein thrombosis from residual thrombosis.

    PubMed

    Tan, Melanie; Mol, Gerben C; van Rooden, Cornelis J; Klok, Frederikus A; Westerbeek, Robin E; Iglesias Del Sol, Antonio; van de Ree, Marcel A; de Roos, Albert; Huisman, Menno V

    2014-07-24

    Accurate diagnostic assessment of suspected ipsilateral recurrent deep vein thrombosis (DVT) is a major clinical challenge because differentiating between acute recurrent thrombosis and residual thrombosis is difficult with compression ultrasonography (CUS). We evaluated noninvasive magnetic resonance direct thrombus imaging (MRDTI) in a prospective study of 39 patients with symptomatic recurrent ipsilateral DVT (incompressibility of a different proximal venous segment than at the prior DVT) and 42 asymptomatic patients with at least 6-month-old chronic residual thrombi and normal D-dimer levels. All patients were subjected to MRDTI. MRDTI images were judged by 2 independent radiologists blinded for the presence of acute DVT and a third in case of disagreement. The sensitivity, specificity, and interobserver reliability of MRDTI were determined. MRDTI demonstrated acute recurrent ipsilateral DVT in 37 of 39 patients and was normal in all 42 patients without symptomatic recurrent disease for a sensitivity of 95% (95% CI, 83% to 99%) and a specificity of 100% (95% CI, 92% to 100%). Interobserver agreement was excellent (κ = 0.98). MRDTI images were adequate for interpretation in 95% of the cases. MRDTI is a sensitive and reproducible method for distinguishing acute ipsilateral recurrent DVT from 6-month-old chronic residual thrombi in the leg veins.

  12. Interobserver Variability in Target Definition for Hepatocellular Carcinoma With and Without Portal Vein Thrombus: Radiation Therapy Oncology Group Consensus Guidelines

    SciTech Connect

    Hong, Theodore S.; Bosch, Walter R.; Krishnan, Sunil; Kim, Tae K.; Mamon, Harvey J.; Ben-Josef, Edgar; Seong, Jinsil; Haddock, Michael G.; Cheng, Jason C.; Feng, Mary U.; Stephans, Kevin L.; Roberge, David; and others

    2014-07-15

    Purpose: Defining hepatocellular carcinoma (HCC) gross tumor volume (GTV) requires multimodal imaging, acquired in different perfusion phases. The purposes of this study were to evaluate the variability in contouring and to establish guidelines and educational recommendations for reproducible HCC contouring for treatment planning. Methods and Materials: Anonymous, multiphasic planning computed tomography scans obtained from 3 patients with HCC were identified and distributed to a panel of 11 gastrointestinal radiation oncologists. Panelists were asked the number of HCC cases they treated in the past year. Case 1 had no vascular involvement, case 2 had extensive portal vein involvement, and case 3 had minor branched portal vein involvement. The agreement between the contoured total GTVs (primary + vascular GTV) was assessed using the generalized kappa statistic. Agreement interpretation was evaluated using Landis and Koch's interpretation of strength of agreement. The S95 contour, defined using the simultaneous truth and performance level estimation (STAPLE) algorithm consensus at the 95% confidence level, was created for each case. Results: Of the 11 panelists, 3 had treated >25 cases in the past year, 2 had treated 10 to 25 cases, 2 had treated 5 to 10 cases, 2 had treated 1 to 5 cases, 1 had treated 0 cases, and 1 did not respond. Near perfect agreement was seen for case 1, and substantial agreement was seen for cases 2 and 3. For case 2, there was significant heterogeneity in the volume identified as tumor thrombus (range 0.58-40.45 cc). For case 3, 2 panelists did not include the branched portal vein thrombus, and 7 panelists contoured thrombus separately from the primary tumor, also showing significant heterogeneity in volume of tumor thrombus (range 4.52-34.27 cc). Conclusions: In a group of experts, excellent agreement was seen in contouring total GTV. Heterogeneity exists in the definition of portal vein thrombus that may impact treatment planning

  13. Magnetic resonance venography to assess thrombus resolution with edoxaban monotherapy versus parenteral anticoagulation/warfarin for symptomatic deep vein thrombosis: A multicenter feasibility study

    PubMed Central

    Piazza, Gregory; Mani, Venkatesh; Goldhaber, Samuel Z; Grosso, Michael A; Mercuri, Michele; Lanz, Hans J; Schussler, Steven; Hsu, Ching; Chinigo, Amy; Ritchie, Bruce; Nadar, Venkatesh; Cannon, Kevin; Pullman, John; Concha, Mauricio; Schul, Marlin; Fayad, Zahi A

    2016-01-01

    The feasibility of magnetic resonance venography (MRV) for measuring change in thrombus volume with a novel anticoagulation regimen versus standard anticoagulation in patients with symptomatic deep vein thrombosis (DVT) has not been assessed. Our aim was to study the feasibility of MRV to measure change in thrombus volume in patients with acute symptomatic objectively confirmed proximal DVT in an open-label multicenter trial (edoxaban Thrombus Reduction Imaging Study, eTRIS). We randomized patients in a 2:1 allocation ratio to edoxaban 90 mg/day for 10 days followed by 60 mg/day versus parenteral anticoagulation bridging to warfarin for 3 months. The primary efficacy outcome was a surrogate end point of the relative change in MRV-quantified thrombus volume from baseline to Day 14–21. A total of 85 eligible patients from 26 study sites were randomized to edoxaban monotherapy (n=56) versus parenteral anticoagulation as a ‘bridge’ to warfarin (n=29). The mean relative change in MRV-quantified thrombus volume from baseline to Day 14–21 was similar in patients treated with edoxaban and parenteral anticoagulation as a ‘bridge’ to warfarin (−50.1% vs −58.9%; 95% confidence interval of treatment difference, −12.7%, 30.2%). However, thrombus extension was observed in eight patients in the edoxaban monotherapy group and in none in the warfarin group. Rates of recurrent venous thromboembolism (3.6% vs 3.6%, p=0.45) and clinically relevant non-major bleeding (5.4% vs 7.1%, p=0.34) were also similar. No major bleeds occurred in either on-treatment group during the study period. In conclusion, MRV can assess change in thrombus volume in patients with acute DVT randomized to two different anticoagulant regimens. ClinicalTrials.gov Identifier: NCT01662908 Investigational New Drug (IND) Application: Edoxaban IND # 63266 PMID:27165711

  14. Thrombus Aspirated from Patients with ST-Elevation Myocardial Infarction: Association between 3-Nitrotyrosine and Inflammatory Markers - Insights from ARTERIA Study.

    PubMed

    Dominguez-Rodriguez, Alberto; Abreu-Gonzalez, Pedro; Consuegra-Sanchez, Luciano; Avanzas, Pablo; Sanchez-Grande, Alejandro; Conesa-Zamora, Pablo

    2016-01-01

    Recent studies have demonstrated that inflammatory cells are a component that plays a role in thrombus formation in ST-elevation myocardial infarction (STEMI). 3-nitrotyrosine (3-NO2-Tyr), a specific marker for protein modification by nitric oxide-derived oxidants, is increased in human atherosclerotic lesions. The purpose of this study was to determine the possible association of inflammatory markers of coronary thrombi with nitroxidative stress. Intracoronary thrombus (n=51) and blood from the systemic circulation were obtained by thromboaspiration in 138 consecutive STEMI patients presenting for primary percutaneous coronary intervention (PCI). Each blood and intracoronary thrombus were measured simultaneously the following biomarkers: C-reactive protein (CRP), 3-NO2-Tyr, soluble CD 40 ligand (sCD40L), vascular cellular adhesion molecule-1 (VCAM-1) and haemoglobin content (only in coronary thrombus). Time delay in minutes from symptom onset to PCI was 244 ± 324. Serum CRP was positively correlated to CRP content in the thrombus (r= 0.395; p = 0.02) and serum sCD40L was negatively correlated to sCD40L in the thrombus (r= -0.394; p = 0.02). Patients were divided into tertiles according to thrombi 3-NO2-Tyr concentration: 1(st)tertile (<0.146ng/mg), 2(nd)tertile (0.146-0.485ng/mg) and 3(rd)tertile (>0.485ng/mg). Thus, thrombus in the highest tertile had significantly higher levels of CRP (p=0.002), VCAM-1 (p=0.003) and haemoglobin (p=0.002). In conclusion, the present study demonstrated that coronary thrombi with higher levels of 3-NO2-Tyr content often contain more inflammatory markers which could have a direct impact on the efficacy of drugs or devices used for coronary reperfusion. PMID:27429583

  15. Thrombus Aspirated from Patients with ST-Elevation Myocardial Infarction: Association between 3-Nitrotyrosine and Inflammatory Markers - Insights from ARTERIA Study

    PubMed Central

    Dominguez-Rodriguez, Alberto; Abreu-Gonzalez, Pedro; Consuegra-Sanchez, Luciano; Avanzas, Pablo; Sanchez-Grande, Alejandro; Conesa-Zamora, Pablo

    2016-01-01

    Recent studies have demonstrated that inflammatory cells are a component that plays a role in thrombus formation in ST-elevation myocardial infarction (STEMI). 3-nitrotyrosine (3-NO2-Tyr), a specific marker for protein modification by nitric oxide-derived oxidants, is increased in human atherosclerotic lesions. The purpose of this study was to determine the possible association of inflammatory markers of coronary thrombi with nitroxidative stress. Intracoronary thrombus (n=51) and blood from the systemic circulation were obtained by thromboaspiration in 138 consecutive STEMI patients presenting for primary percutaneous coronary intervention (PCI). Each blood and intracoronary thrombus were measured simultaneously the following biomarkers: C-reactive protein (CRP), 3-NO2-Tyr, soluble CD 40 ligand (sCD40L), vascular cellular adhesion molecule-1 (VCAM-1) and haemoglobin content (only in coronary thrombus). Time delay in minutes from symptom onset to PCI was 244 ± 324. Serum CRP was positively correlated to CRP content in the thrombus (r= 0.395; p = 0.02) and serum sCD40L was negatively correlated to sCD40L in the thrombus (r= -0.394; p = 0.02). Patients were divided into tertiles according to thrombi 3-NO2-Tyr concentration: 1sttertile (<0.146ng/mg), 2ndtertile (0.146-0.485ng/mg) and 3rdtertile (>0.485ng/mg). Thus, thrombus in the highest tertile had significantly higher levels of CRP (p=0.002), VCAM-1 (p=0.003) and haemoglobin (p=0.002). In conclusion, the present study demonstrated that coronary thrombi with higher levels of 3-NO2-Tyr content often contain more inflammatory markers which could have a direct impact on the efficacy of drugs or devices used for coronary reperfusion. PMID:27429583

  16. Thrombus Aspirated from Patients with ST-Elevation Myocardial Infarction: Association between 3-Nitrotyrosine and Inflammatory Markers - Insights from ARTERIA Study.

    PubMed

    Dominguez-Rodriguez, Alberto; Abreu-Gonzalez, Pedro; Consuegra-Sanchez, Luciano; Avanzas, Pablo; Sanchez-Grande, Alejandro; Conesa-Zamora, Pablo

    2016-01-01

    Recent studies have demonstrated that inflammatory cells are a component that plays a role in thrombus formation in ST-elevation myocardial infarction (STEMI). 3-nitrotyrosine (3-NO2-Tyr), a specific marker for protein modification by nitric oxide-derived oxidants, is increased in human atherosclerotic lesions. The purpose of this study was to determine the possible association of inflammatory markers of coronary thrombi with nitroxidative stress. Intracoronary thrombus (n=51) and blood from the systemic circulation were obtained by thromboaspiration in 138 consecutive STEMI patients presenting for primary percutaneous coronary intervention (PCI). Each blood and intracoronary thrombus were measured simultaneously the following biomarkers: C-reactive protein (CRP), 3-NO2-Tyr, soluble CD 40 ligand (sCD40L), vascular cellular adhesion molecule-1 (VCAM-1) and haemoglobin content (only in coronary thrombus). Time delay in minutes from symptom onset to PCI was 244 ± 324. Serum CRP was positively correlated to CRP content in the thrombus (r= 0.395; p = 0.02) and serum sCD40L was negatively correlated to sCD40L in the thrombus (r= -0.394; p = 0.02). Patients were divided into tertiles according to thrombi 3-NO2-Tyr concentration: 1(st)tertile (<0.146ng/mg), 2(nd)tertile (0.146-0.485ng/mg) and 3(rd)tertile (>0.485ng/mg). Thus, thrombus in the highest tertile had significantly higher levels of CRP (p=0.002), VCAM-1 (p=0.003) and haemoglobin (p=0.002). In conclusion, the present study demonstrated that coronary thrombi with higher levels of 3-NO2-Tyr content often contain more inflammatory markers which could have a direct impact on the efficacy of drugs or devices used for coronary reperfusion.

  17. Influence of red blood cell concentration on the initiation time of blood coagulation: risk of thrombus formation in pregnant females with anemia.

    PubMed

    Sagesaka, Toshiaki; Juen, Hiroyasu; Hayashi, Masatoshi

    2007-01-01

    The influence of a change in red blood cell (RBC) concentration on the initiation time of blood coagulation (Ti) in pregnant and non-pregnant females was investigated using a damped oscillation rheometer to evaluate the risk of hemorrhagic tendency or thrombus formation. The blood samples from 40 female volunteers (20 pregnants and 20 non-pregnants) were examined. After centrifuging some portion of each blood sample, an appropriate volume was taken from the RBC layer to make an artificially diluted blood, or to add it to the autologous blood, making an artificially concentrated blood. The Ti of non-pregnant females was significantly reduced with increasing the RBC concentration from 3.75+/-0.25 to (5.75+/-0.25)x10(6)/mm(3). However, the Ti of pregnant females showed almost no change in the RBC concentrations from 3.25+/-0.25 to (5.25+/-0.25)x10(6)/mm(3). These results suggest that RBC concentration plays an important role in accelerating the initial coagulation reaction of blood of non-pregnant females and that a hypercoagulant condition caused by pregnancy conceals the effect that changes in RBC concentration have in pregnant females. PMID:17325439

  18. Winter grazing decreases the probability of fire-induced mortality of bunchgrasses and may reduce wildfire size: a response to Smith et al (this issue)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent commentary by Smith et al. (this issue) attempted to discount the findings of our study (Davies et al. this issue) by claiming that our study contained methodological errors and lacked the data necessary to support our conclusions, in particular that winter grazing may reduce the probabilit...

  19. Promotion of experimental thrombus formation by the procoagulant activity of breast cancer cells

    PubMed Central

    Berny-Lang, MA; Aslan, JE; Tormoen, GW; Patel, IA; Bock, PE; Gruber, A

    2011-01-01

    The routine observation of tumor emboli in the peripheral blood of patients with carcinomas raises questions about the clinical relevance of these circulating tumor cells. Thrombosis is a common clinical manifestation of cancer and circulating tumor cells may play a pathogenetic role in this process. The presence of coagulation-associated molecules on cancer cells has been described, but the mechanisms by which circulating tumor cells augment or alter coagulation remains unclear. In this study we utilized suspensions of a metastatic adenocarcinoma cell line, MDA-MB-231, and a non-metastatic breast epithelial cell line, MCF-10A, as models of circulating tumor cells to determine the thromobogenic activity of these blood-foreign cells. In human plasma, both metastatic MDA-MB-231 cells and non-metastatic MCF-10A cells significantly enhanced clotting kinetics. The effect of MDA-MB-231 and MCF-10A cells on clotting times was cell number-dependent and inhibited by a neutralizing antibody to tissue factor (TF) as well as inhibitors of activated factor X and thrombin. Using fluorescence microscopy, we found that both MDA-MB-231 and MCF-10A cells supported the binding of fluorescently-labeled thrombin. Furthermore, in a model of thrombus formation under pressure-driven flow, MDA-MB-231 and MCF-10A cells significantly decreased the time to occlusion. Our findings indicate that the presence of breast epithelial cells in blood can stimulate coagulation in a TF-dependent manner, suggesting that tumor cells that enter the circulation may promote the formation of occlusive thrombi under shear flow conditions. PMID:21301066

  20. A chimeric platelet-targeted urokinase prodrug selectively blocks new thrombus formation.

    PubMed

    Fuentes, Rudy E; Zaitsev, Sergei; Ahn, Hyun Sook; Hayes, Vincent; Kowalska, M Anna; Lambert, Michele P; Wang, Yuhuan; Siegel, Donald L; Bougie, Daniel W; Aster, Richard H; Myers, Daniel D; Stepanova, Victoria; Cines, Douglas B; Muzykantov, Vladimir R; Poncz, Mortimer

    2016-02-01

    The use of fibrinolytic agents to prevent new thrombus formation is limited by an increased risk of bleeding due to lysis of hemostatic clots that prevent hemorrhage in damaged blood vessels. We sought to develop an agent that provides thromboprophylaxis without carrying a significant risk of causing systemic fibrinolysis or disrupting hemostatic clots. We previously showed that platelet (PLT) α granule-delivered urokinase plasminogen activator (uPA) is highly effective in preventing thrombosis, while being associated with little systemic fibrinolysis or bleeding. Here, we generated a chimeric prodrug composed of a single-chain version of the variable region of an anti-αIIbβ3 mAb fused to a thrombin-activatable, low-molecular-weight pro-uPA (PLT/uPA-T). PLT/uPA-T recognizes human αIIbβ3 on both quiescent and activated platelets and is enzymatically activated specifically by thrombin. We found that this prodrug binds tightly to human platelets even after gel filtration, has a prolonged half-life in mice transgenic for human αIIb compared with that of uPA-T, and prevents clot formation in a microfluidic system. Importantly, in two murine injury models, PLT/uPA-T did not lyse preexisting clots, even when administration was delayed by as little as 10 minutes, while it concurrently prevented the development of nascent thrombi. Thus, PLT/uPA-T represents the prototype of a platelet-targeted thromboprophylactic agent that selectively targets nascent over preexisting thrombi. PMID:26690701

  1. Intracardiac thrombus in Behçet's disease: four new cases and a comprehensive literature review.

    PubMed

    Aksu, Tolga; Tufekcioglu, Omac

    2015-07-01

    Behçet's disease (BD) is a multisystem inflammatory disorder. Intracardiac thrombus formation (ICTF) is an uncommon but important complication of BD. To highlight recent insights into this disease, we aimed to review ICTF and other systemic involvements associated with ICTF in BD. We conducted a comprehensive review of the relevant literature in MEDLINE and EMBASE from 1966 to 2014 to analyze cumulated data about ICTF in BD. We aimed to evaluate 93 cases of BD with ICT (group 1), four of which have been recently identified and have not been discussed in the relevant literature yet, and to compare the frequency of pulmonary, venous and arterial involvements in group 1 and general Behçet population (group 2). The right heart was the most common site of ICTF in group 1. Pulmonary involvement, venous involvement (especially venous thrombosis) and arterial involvement were more frequent in group 1 than in group 2 (56 vs. 0.7 %, 42 vs. 10 % and 38 vs. 0.8 %, respectively, p < 0.0001). The diagnosis of BD should be considered if a patient presents with a mass in the right-sided cardiac chambers, even in the absence of the characteristic clinical manifestations of the illness. This approach is particularly applicable if the patient is a young man from the Mediterranean basin or the Middle East. All Behçet patients with ICTF must be investigated with thoracic computed tomography for pulmonary and arterial involvements and lower extremity venous Doppler ultrasonography for venous thrombosis, regardless of whether they are symptomatic for these systems. PMID:25381640

  2. Promotion of experimental thrombus formation by the procoagulant activity of breast cancer cells

    NASA Astrophysics Data System (ADS)

    Berny-Lang, M. A.; Aslan, J. E.; Tormoen, G. W.; Patel, I. A.; Bock, P. E.; Gruber, A.; McCarty, O. J. T.

    2011-02-01

    The routine observation of tumor emboli in the peripheral blood of patients with carcinomas raises questions about the clinical relevance of these circulating tumor cells. Thrombosis is a common clinical manifestation of cancer, and circulating tumor cells may play a pathogenetic role in this process. The presence of coagulation-associated molecules on cancer cells has been described, but the mechanisms by which circulating tumor cells augment or alter coagulation remains unclear. In this study we utilized suspensions of a metastatic adenocarcinoma cell line, MDA-MB-231, and a non-metastatic breast epithelial cell line, MCF-10A, as models of circulating tumor cells to determine the thromobogenic activity of these blood-foreign cells. In human plasma, both metastatic MDA-MB-231 cells and non-metastatic MCF-10A cells significantly enhanced clotting kinetics. The effect of MDA-MB-231 and MCF-10A cells on clotting times was cell number-dependent and inhibited by a neutralizing antibody to tissue factor (TF) as well as inhibitors of activated factor X and thrombin. Using fluorescence microscopy, we found that both MDA-MB-231 and MCF-10A cells supported the binding of fluorescently labeled thrombin. Furthermore, in a model of thrombus formation under pressure-driven flow, MDA-MB-231 and MCF-10A cells significantly decreased the time to occlusion. Our findings indicate that the presence of breast epithelial cells in blood can stimulate coagulation in a TF-dependent manner, suggesting that tumor cells that enter the circulation may promote the formation of occlusive thrombi under shear flow conditions.

  3. A chimeric platelet-targeted urokinase prodrug selectively blocks new thrombus formation

    PubMed Central

    Fuentes, Rudy E.; Zaitsev, Sergei; Ahn, Hyun Sook; Hayes, Vincent; Kowalska, M. Anna; Lambert, Michele P.; Wang, Yuhuan; Siegel, Donald L.; Bougie, Daniel W.; Aster, Richard H.; Myers, Daniel D.; Stepanova, Victoria; Cines, Douglas B.; Muzykantov, Vladimir R.; Poncz, Mortimer

    2015-01-01

    The use of fibrinolytic agents to prevent new thrombus formation is limited by an increased risk of bleeding due to lysis of hemostatic clots that prevent hemorrhage in damaged blood vessels. We sought to develop an agent that provides thromboprophylaxis without carrying a significant risk of causing systemic fibrinolysis or disrupting hemostatic clots. We previously showed that platelet (PLT) α granule–delivered urokinase plasminogen activator (uPA) is highly effective in preventing thrombosis, while being associated with little systemic fibrinolysis or bleeding. Here, we generated a chimeric prodrug composed of a single-chain version of the variable region of an anti-αIIbβ3 mAb fused to a thrombin-activatable, low-molecular-weight pro-uPA (PLT/uPA-T). PLT/uPA-T recognizes human αIIbβ3 on both quiescent and activated platelets and is enzymatically activated specifically by thrombin. We found that this prodrug binds tightly to human platelets even after gel filtration, has a prolonged half-life in mice transgenic for human αIIb compared with that of uPA-T, and prevents clot formation in a microfluidic system. Importantly, in two murine injury models, PLT/uPA-T did not lyse preexisting clots, even when administration was delayed by as little as 10 minutes, while it concurrently prevented the development of nascent thrombi. Thus, PLT/uPA-T represents the prototype of a platelet-targeted thromboprophylactic agent that selectively targets nascent over preexisting thrombi. PMID:26690701

  4. Hepatic resection or transarterial chemoembolization for hepatocellular carcinoma with portal vein tumor thrombus

    PubMed Central

    Zheng, Ninggang; Wei, Xiaodong; Zhang, Dongzhi; Chai, Wenxiao; Che, Ming; Wang, Jiangye; Du, Binbin

    2016-01-01

    Abstract The role of hepatic resection in hepatocellular carcinoma (HCC) with accompanying portal vein tumor thrombus (PVTT) remains controversial. This study aimed to evaluate the surgical outcomes of hepatic resection compared with those of transarterial chemoembolization (TACE) in HCC patients. A retrospective study was conducted using the medical records of 230 HCC patients with portal vein invasion who underwent hepatic resection (96 patients) or TACE (134 patients). The baseline characteristics, tumor characteristics, clinicopathological parameters, and overall survival rates were compared between the 2 groups. The baseline and tumor characteristics were comparable between the hepatic resection and TACE groups. The overall complication rate was 35.4% in the hepatic resection group, which was significantly lower than that in the TACE group (73.0%, P <0.001). However, the serious complication rate (grade ≥3) in the hepatic resection group was 13.5%, which was significantly higher than that in the TACE group (P = 0.003). The cumulative overall survival rates at 1, 3, and 5 years in the hepatic resection group were 86.5%, 60.4%, and 33.3%, respectively. These rates were much higher than those in the TACE group (1-year: 77.6%; 3-year: 47.8%; and 5-year: 20.9%; P = 0.021). The long-term survival was notably better in the patients with types I and II PVTT than in the patients with types III and IV PVTT (P <0.05). The univariate and multivariate analyses indicated that types III and IV PVTT and TACE may have contributed to the poor overall survival following surgery. In HCC patients with PVTT and compensated liver function, hepatic resection is a safe and effective surgical protocol, particularly for patients with type I or II PVTT. PMID:27367992

  5. A long-surviving case of gastric cancer with main portal vein tumor thrombus after surgical resection and postoperative S-1 therapy.

    PubMed

    Sato, Shinsuke; Nagai, Erina; Taki, Yusuke; Watanabe, Masaya; Takahashi, Michiro; Kyoden, Yusuke; Ohata, Ko; Kanemoto, Hideyuki; Oba, Noriyuki; Taku, Keisei; Suzuki, Makoto; Takagi, Masakazu

    2016-08-01

    Gastric cancer patients with main portal vein tumor thrombus usually have a short survival time, owing to its aggressive behavior. Herein, we report a long-surviving case of gastric cancer with main portal vein tumor thrombus. A 78-year-old man presenting with anorexia and body weight loss was diagnosed with gastric cancer. The patient was referred to our hospital for further examination and treatment. Endoscopy revealed a type 3 tumor (8.0 cm in length) in the body of the stomach. Biopsy led to the diagnosis of moderately differentiated adenocarcinoma. Enhanced computed tomography revealed a large tumor thrombus extending from the gastric coronary vein to the portal trunk. A total gastrectomy with lymphadenectomy, splenectomy, and thrombectomy was performed. Postoperative chemotherapy with S-1 was administered for 18 months. The patient died a natural death without recurrence at 49 postoperative months. To the best of our knowledge, the patient was the oldest to be diagnosed with gastric cancer with main portal vein tumor thrombus at diagnosis, who survived >36 months. Although gastric cancer with main portal vein tumor thrombus is a rare occurrence, its prognosis is extremely poor. Intensive surgery and long-term chemotherapy may be effective at improving survival time in these patients.

  6. Inhibition of SA Node at Supine Position in Right Atrial Thrombus Complicating Behçet’s Disease – From Cardiac Surgical Point of View

    PubMed Central

    Hijazi, Emad Mohamed; Ibdah, Rasheed Khaled; Rawashdeh, Sukina Ismael; Saadeh, Abdullah Mahmoud; Al-Balas, Hamzeh Ibrahim

    2016-01-01

    Patient: Female, 27 Final Diagnosis: Right atrial thrombus compressing the sinoatrial node Symptoms: Dyspnea • cough and hemoptysis with supine bradycardia reaching 36/min and dizziness Medication: — Clinical Procedure: Cardiac surgical intervention removing the mechanical cause if conservative management failed can be done safely Specialty: Surgery Objective: Rare disease Background: Behçet’s disease (BD) is a chronic multi-systemic disease of unknown cause. Intra-cardiac thrombus (ICT) complicating BD is extremely rare. In general, cardiac manifestations in BD are associated with poor prognosis. Chest computed tomography (CT) scan and echocardiogram are excellent modalities for diagnosis and patient assessment. Cardiac surgical intervention can be done safely using an on-pump technique when medical management has failed. Case Report: We report on a case of a 27-year-old Jordanian woman diagnosed with BD who presented with dyspnea, cough, and hemoptysis, with supine bradycardia reaching 36 beats/minute and dizziness which disappear on sitting or standing position, and with heart rate reaching 76 beats/minute. Right atrial thrombus was identified using transthoracic echocardiogram and chest CT scan. After medical management failed, cardiac surgical intervention became an option and targeted extraction of the right atrial thrombus compressing the sinoatrial node (SA node). Conclusions: In BD, right atrial thrombus compressing the SA node is rare. If conservative management has failed, cardiac surgical intervention removing the mechanical cause can be done safely, either using on-pump with cross clamp or on-pump with beating heart technique. PMID:27311379

  7. In situ capping for size control of monochalcogenides (ZnS, CdS, and SnS) nanocrystals produced by anaerobic metal-reducing bacteria

    DOE PAGESBeta

    Jang, Gyoung Gug; Jacobs, Christopher B.; Ivanov, Ilia N.; Joshi, Pooran C.; Meyer, III, Harry M.; Kidder, Michelle; Armstrong, Beth L.; Datskos, Panos G.; Graham, David E.; Moon, Ji -Won

    2015-07-24

    Metal monochalcogenide quantum dot nanocrystals of ZnS, CdS and SnS were prepared by anaerobic, metal-reducing bacteria using in situ capping by oleic acid or oleylamine. Furthermore, the capping agent preferentially adsorbs on the surface of the nanocrystal, suppressing the growth process in the early stages, thus leading to production of nanocrystals with a diameter of less than 5 nm.

  8. Report: Maximizing recycling participation to reduce waste to landfill: a study of small to medium-sized enterprises in Hobart, Tasmania, Australia.

    PubMed

    Parsons, Sam; Kriwoken, Lorne K

    2010-05-01

    Small to medium-sized enterprises (SMEs) in Hobart, Tasmania, Australia face many barriers to recycling participation. This study first investigated the volumes and types of waste produced by SMEs. Significant barriers were then identified and key motivators to recycle examined. Using the Australia New Zealand Standard of Industrial Classification, stratified sampling of SMEs (n = 436) was undertaken. Inadequate storage space, paucity of readily available information on recycling services and the lack of staff allocated to sort and recycle were identified as major barriers. Cardboard, paper and plastic waste were produced in large volumes with only a small percentage being recycled and these were identified as target areas for local government. Recommendations include the appointment of a dedicated recycling officer to maximize recycling participation for the reduction of waste to landfill and to undertake further research on minimizing recycling costs.

  9. Variation in the Oral Processing of Everyday Meals Is Associated with Fullness and Meal Size; A Potential Nudge to Reduce Energy Intake?

    PubMed

    Ferriday, Danielle; Bosworth, Matthew L; Godinot, Nicolas; Martin, Nathalie; Forde, Ciarán G; Van Den Heuvel, Emmy; Appleton, Sarah L; Mercer Moss, Felix J; Rogers, Peter J; Brunstrom, Jeffrey M

    2016-01-01

    Laboratory studies have demonstrated that experimental manipulations of oral processing can have a marked effect on energy intake. Here, we explored whether variations in oral processing across a range of unmodified everyday meals could affect post-meal fullness and meal size. In Study 1, female participants (N = 12) attended the laboratory over 20 lunchtime sessions to consume a 400-kcal portion of a different commercially available pre-packaged meal. Prior to consumption, expected satiation was assessed. During each meal, oral processing was characterised using: (i) video-recordings of the mouth and (ii) real-time measures of plate weight. Hunger and fullness ratings were elicited pre- and post-consumption, and for a further three hours. Foods that were eaten slowly had higher expected satiation and delivered more satiation and satiety. Building on these findings, in Study 2 we selected two meals (identical energy density) from Study 1 that were equally liked but maximised differences in oral processing. On separate days, male and female participants (N = 24) consumed a 400-kcal portion of either the "fast" or "slow" meal followed by an ad libitum meal (either the same food or a dessert). When continuing with the same food, participants consumed less of the slow meal. Further, differences in food intake during the ad libitum meal were not compensated at a subsequent snacking opportunity an hour later. Together, these findings suggest that variations in oral processing across a range of unmodified everyday meals can affect fullness after consuming a fixed portion and can also impact meal size. Modifying food form to encourage increased oral processing (albeit to a lesser extent than in experimental manipulations) might represent a viable target for food manufacturers to help to nudge consumers to manage their weight. PMID:27213451

  10. Variation in the Oral Processing of Everyday Meals Is Associated with Fullness and Meal Size; A Potential Nudge to Reduce Energy Intake?

    PubMed Central

    Ferriday, Danielle; Bosworth, Matthew L.; Godinot, Nicolas; Martin, Nathalie; Forde, Ciarán G.; Van Den Heuvel, Emmy; Appleton, Sarah L.; Mercer Moss, Felix J.; Rogers, Peter J.; Brunstrom, Jeffrey M.

    2016-01-01

    Laboratory studies have demonstrated that experimental manipulations of oral processing can have a marked effect on energy intake. Here, we explored whether variations in oral processing across a range of unmodified everyday meals could affect post-meal fullness and meal size. In Study 1, female participants (N = 12) attended the laboratory over 20 lunchtime sessions to consume a 400-kcal portion of a different commercially available pre-packaged meal. Prior to consumption, expected satiation was assessed. During each meal, oral processing was characterised using: (i) video-recordings of the mouth and (ii) real-time measures of plate weight. Hunger and fullness ratings were elicited pre- and post-consumption, and for a further three hours. Foods that were eaten slowly had higher expected satiation and delivered more satiation and satiety. Building on these findings, in Study 2 we selected two meals (identical energy density) from Study 1 that were equally liked but maximised differences in oral processing. On separate days, male and female participants (N = 24) consumed a 400-kcal portion of either the “fast” or “slow” meal followed by an ad libitum meal (either the same food or a dessert). When continuing with the same food, participants consumed less of the slow meal. Further, differences in food intake during the ad libitum meal were not compensated at a subsequent snacking opportunity an hour later. Together, these findings suggest that variations in oral processing across a range of unmodified everyday meals can affect fullness after consuming a fixed portion and can also impact meal size. Modifying food form to encourage increased oral processing (albeit to a lesser extent than in experimental manipulations) might represent a viable target for food manufacturers to help to nudge consumers to manage their weight. PMID:27213451

  11. A Tc-99m labeled laminin derived peptide, Tc-99m-YIGSR for thrombus specific imaging

    SciTech Connect

    Wang, G.J.; Oster, Z.H.; Som, P.

    1994-05-01

    Laminin derived adhesive peptides were studied as potential agents for thrombus specific imaging. Using a novel peptide Tc-99m labeling method studies were performed in vitro using human whole blood clots and platelets, and in vivo scintigraphy in animals with experimental thrombi. Aliquots of 0.1 ml human blood were placed in inclined Petri dishes until clot was well formed. Clots were rinsed 3x with phosphate buffer and 10 {mu}Ci Tc-99m YIGSR II was added. After incubation at room temperature for 1 hr, clots were again washed 3x. Residual activity was measured. Platelets were harvested using routine methods and incubated with Tc-99m YIGSR II, washed and assayed. Blocking experiments using cold YIGSR II showed that the Tc-99m labeled peptide preparation YIGSR II binds specifically and selectively to clot and platelets as compared to control experiments using nonspecific human Tc-99m IgG. Tissue distribution studies showed rapid blood clearance, urinary excretion and to a lesser degree GI tract excretion. Tc-99m YIGSR II was lower in all organs except kidneys compared to Tc-99m 50 H.19, Tc-99m IgG and Tc-99m YIGSR I. Tc-99m-YIGSR II consistently visualized thrombi within 30 min p.i. In vivo scintigraphic (thrombus/contralateral side) ratio was 3:1 and ex vivo direct counting (thrombosed to nonthrombosed vessel segment) was 5.4: 1. Compared to monoclonal antibodies peptide preparations are non- or minimally immunogenic, preparation is probably less expensive and there is also less danger of viral DNA contamination. These considerations and our data indicate that the Tc-99m-YIGSR II peptide has significant potential as a thrombus imaging agent.

  12. Increased von Willebrand factor, P-selectin and fibrin content in occlusive thrombus resistant to lytic therapy.

    PubMed

    Sambola, Antonia; García Del Blanco, Bruno; Ruiz-Meana, Marisol; Francisco, Jaume; Barrabés, José A; Figueras, Jaume; Bañeras, Jordi; Otaegui, Imanol; Rojas, Angeles; Vilardosa, Úrsula; Montaner, Joan; García-Dorado, David

    2016-06-01

    Therapeutic fibrinolysis is ineffective in 40 % of ST-segment elevation acute myocardial infarction (STEMI) patients, but understanding of the mechanisms is incomplete. It was our aim to compare the composition of coronary thrombus in lysis-resistant STEMI patients with that of lysis-sensitive patients. Intracoronary thrombi (n=64) were obtained by aspiration in consecutive STEMI patients. Of them, 20 had received fibrinolysis and underwent rescue percutaneous coronary intervention (r-PCI, lysis-resistant patients) and 44 underwent primary PCI (p-PCI). Lysis-sensitivity was determined in vitro by clot permeability measurements and turbidimetric lysis in plasma of 44 patients undergoing p-PCI and 20 healthy donors. Clot-lysis sensitivity was defined as a clot-lysis time not greater than 1 SD over the mean of healthy donors. Coronary thrombus composition in 20 lysis-resistant and in 20 lysis-sensitive patients was analysed by immunofluorescence with confocal microscopy. Plasma biomarkers (P-selectin, VWF, PAI-1, t-PA, D-dimer, TF pathway markers, plasmin and CD34+) were measured simultaneously on peripheral blood. Lysis-resistant clots had higher levels of fibrin (p=0.02), P-selectin (p=0.03) and VWF (p=0.01) than lysis-sensitive clots. Among thrombi obtained ≤ 6 hours after onset of symptoms, those from lysis-resistant patients showed a higher content in fibrin than those from p-PCI patients (p=0.01). Plasma PAI-1 (p=0.02) and D-dimer levels were significantly higher (p=0.003) in lysis-resistant patients, whereas plasmin levels were lower (p=0.03). Multivariate analysis showed the content of fibrin and VWF within thrombus as predictors of thrombolysis resistance. In conclusion, coronary thrombi in STEMI patients resistant to fibrinolysis are characterised by higher fibrin, P-selectin and VWF content than lysis-sensitive thrombi.

  13. Modulation of Platelet Activation and Thrombus Formation Using a Pan-PI3K Inhibitor S14161

    PubMed Central

    Ren, Lijie; Liu, Xiaohui; Wang, Qi; He, Sudan; Wu, Qingyu; Hu, Hu; Mao, Xinliang; Zhu, Li

    2014-01-01

    The phosphatidylinositol 3–kinase (PI3K) signaling pathway is critical in modulating platelet functions. In the present study, we evaluated the effect of S14161, a recently identified pan-class I PI3K inhibitor, on platelet activation and thrombus formation. Results showed that S14161 inhibited human platelet aggregation induced by collagen, thrombin, U46619, and ADP in a dose-dependent manner. Flow cytometric studies showed that S14161 inhibited convulxin- or thrombin-induced P-selectin expression and fibrinogen binding of single platelet. S14161 also inhibited platelet spreading on fibrinogen and clot retraction, processes mediated by outside-in signaling. Using a microfluidic chamber we demonstrated that S14161 decreased platelet adhesion on collagen-coated surface by about 80%. Western blot showed that S14161 inhibited phosphorylation of Akt at both Ser473 and Thr308 sites, and GSK3β at Ser9 in response to collagen, thrombin, or U46619. Comparable studies showed that S14161 has a higher potential bioavailability than LY294002, a prototypical inhibitor of pan-class I PI3K. Finally, the effects of S14161 on thrombus formation in vivo were measured using a ferric chloride-induced carotid artery injury model in mice. The intraperitoneal injection of S14161 (2 mg/kg) to male C57BL/6 mice significantly extended the first occlusion time (5.05±0.99 min, n = 9) compared to the vehicle controls (3.72±0.95 min, n = 8) (P<0.05), but did not prolong the bleeding time (P>0.05). Taken together, our data showed that S14161 inhibits platelet activation and thrombus formation without significant bleeding tendency and toxicity, and considering its potential higher bioavailability, it may be developed as a novel therapeutic agent for the prevention of thrombotic disorders. PMID:25115838

  14. Short-Term Anticoagulant Therapy and Thrombus Location Are Independent Risk Factors for Delayed Recanalization of Deep Vein Thrombosis

    PubMed Central

    Zhang, Chuanlin; Fu, Qining; Zhao, Yu; Mu, Shaoyu; Liu, Liping

    2016-01-01

    Background Prompt recanalization of the vein containing the thrombus is an important goal during the initial treatment of DVT, and risk factors for delayed recanalization in patients with deep vein thrombosis (DVT) in the lower extremities need to be determined. Material/Methods A total of 174 patients with DVT in lower extremities were recruited from June 2014 to March 2015 at our hospital. Duplex ultrasound scanning was conducted for all patients at 1 and 6 months after baseline evaluation. We divided the patients into recanalization and non-recanalization groups and analyzed risk factors for delayed recanalization. Results The univariate analysis revealed that an oral anticoagulant time of less than 3 months and venous thrombus location were risk factors for delayed recanalization (P<0.01). However, age, gender, hypertension, diabetes, pulmonary embolism, incidence factors, the use of catheter-directed thrombolytic (CDT) drugs, and inferior vena cava filter (IVCF) implantation had no influence on the incidence of delayed recanalization in patients with DVT (P>0.05). The multivariate analysis showed that patients with an anticoagulant time of less than 3 months had a lower incidence of recanalization than those with an anticoagulant time of more than 3 months (OR=2.358, P<0.05). The risk of delayed recanalization in patients with proximal DVT was 7 times higher than that in patients with distal DVT. Conclusions Duration of anticoagulant treatment of less than 3 months and venous thrombus location are independent risk factors for delayed recanalization of DVT in the lower extremities. PMID:26790571

  15. The NF-κB specific inhibitor DHMEQ prevents thrombus formation in a mouse model of antiphospholipid syndrome

    PubMed Central

    Nishimura, Misato; Nii, Tokiko; Trimova, Gulzhan; Miura, Shuhei; Umezawa, Kazuo; Ushiyama, Akira; Kubota, Tetsuo

    2013-01-01

    Background: β2-glycoprotein I (β2GPI)-dependent antiphospholipid antibodies (aPLs) are considered to play a pivotal pathogenic role in antiphospholipid syndrome (APS) by inducing the expression of tissue factor, inflammatory cytokines, and chemokines, most of which are dependent upon the NF-κB pathway. Therefore, the NF-κB is regarded as a promising target for the development of a novel therapeutic strategy. However, progress has been limited owing to the fact that there are no widely-used in vivo models, or highly specific inhibitors. Objective:This study aimed to test the effects of an NF-κB-specific inhibitor, DHMEQ, in preventing thrombus formation using an original mouse model of APS. Materials and Methods: Specificity of a monoclonal aPL WB-6 was examined by ELISA. WB-6 was injected into normal BALB/c mice with or without DHMEQ treatment. A pulse laser was radiated to a cutaneous vein in the window of a dorsal skinfold chamber attached to the mouse and thrombus formation was observed and recorded under a microscope. Results: WB-6 bound preferentially to the caldiolipin (CL)-β2GPI complex rather than to CL alone, or β2GPI alone. WB-6, but not isotype-matched control antibody, induced a prothrombotic state in the mice by inducing tissue factor expression upon circulating monocytes, resulting in thrombus formation at the site of laser-induced endothelial injury. This diathesis was almost completely ameliorated by DHMEQ treatment. Conclusions: Inhibition of the NF-κB pathway is a promising strategy for the development of a novel treatment for APS. PMID:24475437

  16. CT Findings of Intrarenal Yolk Sac Tumor with Tumor Thrombus Extending into the Inferior Vena Cava: A Case Report

    PubMed Central

    Lin, ShaoChun; Li, XueHua; Feng, ShiTing; Peng, ZhenPeng; Huang, SiYun; Li, ZiPing

    2014-01-01

    Yolk sac tumor (YST) is a rare germ cell neoplasm of childhood that usually arises from the testis or ovary. The rare cases of YST in various extragonadal locations have been reported, but the primary intrarenal YST is even more uncommon. Here, we report a case of a primary intrarenal YST with tumor thrombus of the inferior vena cava and left renal vein in a 2-year-old boy, with an emphasis on the CT features. To our knowledge, this is the first reported case of an intrarenal YST with intravascular involvement. PMID:25246826

  17. Endovascular stent graft repair of thoracic aortic mural thrombus in a patient with polycythemia vera: a word of caution.

    PubMed

    Fukuhara, Shinichi; Tyagi, Samuel; Clarke-Pearson, Emily; Bernik, Thomas

    2015-02-01

    Thoracic aortic mural thrombus (TAMT) is a rare pathology and potential source of cerebral, visceral, and peripheral emboli. We present a 62-year-old male in a hypercoagulable state due to primary polycythemia vera (PV) developed TAMT and catastrophic thromboembolisms despite aggressive medical and surgical management. The outcomes and adverse events of endovascular exclusion of TAMT in the presence of PV are unknown. We would recommend proceeding with extreme caution when performing endovascular exclusion of TAMT, as PV may be a prohibitive risk.

  18. Left ventricular intracardiac thrombus in a patient with Behçet disease successfully treated with immunosuppressive agents without anticoagulation: a case report and review of the literature.

    PubMed

    Lisitsyna, Tatiana; Alekberova, Zemfira; Ovcharov, Pavel; Volkov, Alexander; Korsakova, Julia; Nasonov, Evgeni

    2015-11-01

    Behçet disease (BD) is a chronic multisystem disorder with vasculitis underlying its systemic manifestations. Cardiac involvement and particularly left ventricular intracardiac thrombus are rarely diagnosed in the course of BD and are often associated with poor prognosis. The causes of intracardiac thrombi are unknown. It is plausible that specific proinflammatory pathways resulting in the endothelial cell injury and hypercoagulation contribute to the formation of thrombotic masses in the heart. Known thrombophilic factors such as methylenetetrahydrofolate reductase gene mutations, factor V Leiden mutation, proteins S and C, antithrombin III, activated protein C resistance, and antiphospholipid antibodies may contribute to the formation of intracardiac thrombi in BD. We report a case of a 24-year-old male patient with BD presented with left ventricular thrombus. Transthoracic echocardiography allowed to describe and monitor such a rare cardiac manifestation of the disease. A combination of high-dose corticosteroid and azathioprine successfully dissolved intracardiac thrombus within ten days without anticoagulation.

  19. Design Modifications for Increasing the BOM and EOM Power Output and Reducing the Size and Mass of RTG for the Pluto Mission

    SciTech Connect

    Schock, Alfred; Or, Chuen T; Kumar, Vasanth

    1994-06-01

    A companion paper analyzed the effect on source modules for three specific fuel options, and compared the predicted power output with JPL's latest goals for the Pluto Fast Flyby (PFF) mission. The results showed that a 5-module RTG cannot fully meet JPL's goals with any of the available fuels; and that a 6-module RTG more than meets those goals with Russian fuel, almost meets them with U.S. (Cassini-type) fuel, but still falls far short of meeting them with the depleted fuel from the aged (1982) Galileo spare RTG. The inadequacy of the aged fuel was disappointing,because heat source modules made from it already exist, and their use in PFF could result in substantial cost savings. The present paper describes additional analyses which showed that a six-module RTG with the aged fuel can meet JPL's stipulated power margin with a relatively simple design modification, that a second design modification makes it possible to recover all of the mass and size penalty for going from five to six heat source modules, and that a third modification could raise the EOM power margin to 16%. There are four copies in the file. Cross Reference ESD Files FSC-ESD-217-94-531 (CID #8572)

  20. Design Modifications for Increasing the BOm and EOM Power Output and Reducing the Size and Mass of RTG for the Pluto Mission

    SciTech Connect

    Schock, Alfred; Or, Chuen T; Kumar, Vasanth

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. A companion paper analyzed the effect on source modules for three specific fuel options, and compared the predicted power output with JPL's latest goals for the Pluto Fast Flyby (PFF) mission. The results showed that a 5-module RTG cannot fully meet JPL's goals with any of the available fuels; and that a 6-module RTG more than meets those goals with Russian fuel, almost meets them with U.S. (Cassini-type) fuel, but still falls far short of meeting them with the depleted fuel from the aged (1982) Galileo spare RTG. The inadequacy of the aged fuel was disappointing,because heat source modules made from it already exist, and their use in PFF could result in substantial cost savings. The present paper describes additional analyses which showed that a six-module RTG with the aged fuel can meet JPL's stipulated power margin with a relatively simple design modification, that a second design modification makes it possible to recover all of the mass and size penalty for going from five to six heat source modules, and that a third modification could raise the EOM power margin to 16%.

  1. Manual Thrombus Aspiration and the Improved Survival of Patients With Unstable Angina Pectoris Treated With Percutaneous Coronary Intervention (30 Months Follow-Up)

    PubMed Central

    Yildiz, Bekir S.; Bilgin, Murat; Zungur, Mustafa; Alihanoglu, Yusuf I.; Kilic, Ismail D.; Buber, Ipek; Ergin, Ahmet; Kaftan, Havane A.; Evrengul, Harun

    2016-01-01

    Abstract The clinical effect of intracoronary thrombus aspiration during percutaneous coronary intervention in patients with unstable angina pectoris is unknown. In this study, we aimed to assess how thrombus aspiration during percutaneous coronary intervention affects in-hospital and 30-month mortality and complications in patients with unstable angina pectoris. We undertook an observational cohort study of 645 consecutive unstable angina pectoris patients who had performed percutaneous coronary intervention from February 2011 to March 2013. Before intervention, 159 patients who had culprit lesion with thrombus were randomly assigned to group 1 (thrombus aspiration group) and group 2 (stand-alone percutaneous coronary intervention group). All patients were followed-up 30 months until August 2015. Thrombus aspiration was performed in 64 patients (46%) whose cardiac markers (ie, creatinine kinase [CK-MB] mass and troponin T) were significantly lower after percutaneous coronary intervention than in those of group 2 (CK-MB mass: 3.80 ± 1.11 vs 4.23 ± 0.89, P = 0.012; troponin T: 0.012 ± 0.014 vs 0.018 ± 0.008, P = 0.002). Left ventricular ejection fraction at 6, 12, and 24 months postintervention was significantly higher in the group 1. During a mean follow-up period of 28.87 ± 6.28 months, mortality rates were 6.3% in the group 1 versus 12.9% in the group 2. Thrombus aspiration was also associated with significantly less long-term mortality in unstable angina pectoris patients (adjusted HR: 4.61, 95% CI: 1.16–18.21, P = 0.029). Thrombus aspiration in the context of unstable angina pectoris is associated with a limited elevation in cardiac enzymes during intervention that minimises microembolization and significantly improves both of epicardial flow and myocardial perfusion, as shown by angiographic TIMI flow grade and frame count. Thrombus aspiration during percutaneous coronary intervention in unstable angina pectoris patients

  2. Use of the GuideLiner catheter for aspiration thrombectomy in a patient with ST-elevation myocardial infarction with a large intracoronary thrombus.

    PubMed

    Numasawa, Yohei; Motoda, Hiroyuki; Yamazaki, Hiroyuki; Kuno, Toshiki; Kodaira, Masaki; Fujisawa, Taishi

    2016-04-01

    We report a 67-year-old man with ST-elevation myocardial infarction with a large intracoronary thrombus who was successfully treated with percutaneous thrombectomy using the GuideLiner catheter. This catheter is designed for the "Mother and Child" technique with a rapid exchange system and it has a larger internal diameter than conventional aspiration devices. When aspiration thrombectomy using a conventional aspiration catheter is not feasible or fails, use of the GuideLiner catheter for aspiration of thrombus is a reasonable alternative for primary percutaneous coronary intervention in patients with acute myocardial infarction.

  3. Manual Thrombus Aspiration and the Improved Survival of Patients With Unstable Angina Pectoris Treated With Percutaneous Coronary Intervention (30 Months Follow-Up).

    PubMed

    Yildiz, Bekir S; Bilgin, Murat; Zungur, Mustafa; Alihanoglu, Yusuf I; Kilic, Ismail D; Buber, Ipek; Ergin, Ahmet; Kaftan, Havane A; Evrengul, Harun

    2016-02-01

    The clinical effect of intracoronary thrombus aspiration during percutaneous coronary intervention in patients with unstable angina pectoris is unknown. In this study, we aimed to assess how thrombus aspiration during percutaneous coronary intervention affects in-hospital and 30-month mortality and complications in patients with unstable angina pectoris.We undertook an observational cohort study of 645 consecutive unstable angina pectoris patients who had performed percutaneous coronary intervention from February 2011 to March 2013. Before intervention, 159 patients who had culprit lesion with thrombus were randomly assigned to group 1 (thrombus aspiration group) and group 2 (stand-alone percutaneous coronary intervention group). All patients were followed-up 30 months until August 2015.Thrombus aspiration was performed in 64 patients (46%) whose cardiac markers (ie, creatinine kinase [CK-MB] mass and troponin T) were significantly lower after percutaneous coronary intervention than in those of group 2 (CK-MB mass: 3.80 ± 1.11 vs 4.23 ± 0.89, P = 0.012; troponin T: 0.012 ± 0.014 vs 0.018 ± 0.008, P = 0.002). Left ventricular ejection fraction at 6, 12, and 24 months postintervention was significantly higher in the group 1. During a mean follow-up period of 28.87 ± 6.28 months, mortality rates were 6.3% in the group 1 versus 12.9% in the group 2. Thrombus aspiration was also associated with significantly less long-term mortality in unstable angina pectoris patients (adjusted HR: 4.61, 95% CI: 1.16-18.21, P = 0.029).Thrombus aspiration in the context of unstable angina pectoris is associated with a limited elevation in cardiac enzymes during intervention that minimises microembolization and significantly improves both of epicardial flow and myocardial perfusion, as shown by angiographic TIMI flow grade and frame count. Thrombus aspiration during percutaneous coronary intervention in unstable angina pectoris patients has better

  4. Aspiration thrombectomy in a case of acute myocardial infarction due to coronary emboli in a patient with peripartum cardiomyopathy and mural thrombus.

    PubMed

    Abdulbaki, Abdulrahman; Kocherla, Cyrus; Modi, Kalgi

    2015-01-01

    Acute coronary syndrome (ACS) due to embolic phenomenon in the setting of peripartum cardiomyopathy (PPCM) and left ventricular mural thrombus is a rare occurrence. There have been two known cases described in medical literature. We present a unique case in which catheter-based aspiration thrombectomy was used to successfully treat a patient with ACS due to coronary emboli in the setting of PPCMand left ventricular mural thrombus. We believe this to be the first report of the use of aspiration thrombectomy in such a clinical case.

  5. PAK1-deficiency/down-regulation reduces brood size, activates HSP16.2 gene and extends lifespan in Caenorhabditis elegans.

    PubMed

    Yanase, S; Luo, Y; Maruta, H

    2013-02-01

    There is an increasing evidence that the oncogenic kinase PAK1 is responsible not only for malignant transformation, but also for several other diseases such as inflammatory diseases (asthma and arthritis), infectious diseases including malaria, AIDS, and flu, as well as a series of neuronal diseases/disorders (neurofibromatosis, tuberous sclerosis, Alzheimer's diseases, Huntington's disease, epilepsy, depression, learning deficit, etc.) which often cause premature death. Interestingly, a few natural PAK1-blockers such as curcumin, caffeic acid (CA) and rosmarinic acid (RA) extend the lifespan of the nematode Caenorhabditis elegans or fruit flies. Here, to explore the possibility that C. elegans could provide us with a quick and inexpensive in vivo screening system for a series of more potent but safe (non-toxic) PAK1-blocking therapeutics, we examined the effects of PAK1-deficiency or down-regulation on a few selected functions of this worm, including reproduction, expression of HSP16.2 gene, and lifespan. In short, we found that PAK1 promotes reproduction, whereas it inactivates HSP16.2 gene and shortens lifespan, as do PI-3 kinase (AGE-1), TOR, and insulin-like signalling /ILS (Daf-2) in this worm. These findings not only support the "trade-off" theory on reproduction versus lifespan, but also suggest the possibility that the reduced reproduction (or HSP16.2 gene activation) of this worm could be used as the first indicator of extended lifespan for a quick in vivo screening for PAK1-blockers. PMID:23524941

  6. Inhibitory effect of caffeic acid on ADP-induced thrombus formation and platelet activation involves mitogen-activated protein kinases

    PubMed Central

    Lu, Yu; Li, Quan; Liu, Yu-Ying; Sun, Kai; Fan, Jing-Yu; Wang, Chuan-She; Han, Jing-Yan

    2015-01-01

    Caffeic acid (CA), one of the active constituents of Radix Salvia miltiorrhizae, exhibits antioxidant and anti-inflammatory activities. However, few studies have assessed the ability of CA to inhibit platelet mediated thrombus generation in vivo. In this study, we investigated the antithrombotic effect of CA in mouse cerebral arterioles and venules using intravital microscopy. The antiplatelet activity of CA in ADP stimulated mouse platelets in vitro was also examined in attempt to explore the underlying mechanism. Our results demonstrated that CA (1.25–5 mg/kg) significantly inhibited thrombus formation in vivo. In vitro, CA (25–100 μM) inhibited ADP-induced platelet aggregation, P-selectin expression, ATP release, Ca2+ mobilization, and integrin αIIbβ3 activation. Additionally, CA attenuated p38, ERK, and JNK activation, and enhanced cAMP levels. Taken together, these data provide evidence for the inhibition of CA on platelet-mediated thrombosis in vivo, which is, at least partly, mediated by interference in phosphorylation of ERK, p38, and JNK leading to elevation of cAMP and down-regulation of P-selectin expression and αIIbβ3 activation. These results suggest that CA may have potential for the treatment of aberrant platelet activation-related diseases. PMID:26345207

  7. Detection of lower limb deep venous thrombosis in asymptomatic high risk patients using a new radiolabelled thrombus specific agent

    SciTech Connect

    Butler, S.P.; Rahman, T.; Boyd S.J.

    1995-05-01

    Deep venous thrombosis is a serious consequence of major orthopaedic surgery and non invasive screening with either venous ultrasound or impedance plethysmography is unreliable for detecting or excluding DVT in this group. A new method of thrombus detection has been devised using Tc-99m labelled inhibited recombinant tissue plasminogen activator. The accuracy of scanning with this new radiopharmaceutical in asymptomatic high risk patients was evaluated using venography as the gold standard. 36 consecutive asymptomatic high risk patients (17 total hip, 19 total knee replacements) underwent both a contrast venogram on the operated leg and scintigraphic scan 7 days following operation. Scintigraphic imaging was performed at 4 hours post injection. For the purpose of this analysis, each venogram was divided into a proximal and a distal segment. Venograms were interpreted as being positive, negative or uninterpretable in each segment. Similar analysis of the scintigraphic scans was performed except that all segments were considered to be of diagnostic quality. 57 segments were able to be analysed. Of the 13 thrombosed segments (1 proximal, 12 calf), 12 had positive scans; in the 44 non thrombosed segments, 40 had negative scans. Thus in detecting lower limb thrombosis, scanning had a sensitivity of 92% and a specificity of 91%. Scintigraphic scanning with this new radiopharmaceutical permits accurate detection of thrombus in high risk patients.

  8. Right Ventricular Thrombus and Cerebral Artery Aneurysm in a Patient with Behçet’s Disease

    PubMed Central

    Sabzi, Feridoun; Mirzaei, Samaneh; Faraji, Reza

    2016-01-01

    We report a 35-year-old woman referred to the Imam Ali Hospital, Kermanshah, Iran, in July 2014 for evaluation of postoperative dyspnoea after neurosurgery performed seven days previously for a ruptured cerebral artery aneurysm. She was known to have Behçet’s disease with a history of recurrent oral and genital aphthous ulcers and uveitis. At referral, her symptoms included vertigo, dysarthria, palpitations and chest pain. Transthoracic echocardiography (TTE) revealed a large thrombus in her right ventricle outflow tract and open-heart surgery was performed eight days after the previous surgery to remove the clot. The postoperative period was complicated by transient acute renal failure, which resolved spontaneously. The patient was discharged 13 days after the cardiac surgery on warfarin, prednisolone, azathioprine and cyclophosphamide. Cyclophosphamide and azathioprine were discontinued after three months as the symptoms had completely resolved; however, prednisolone was continued due to recurrent uveitis. A 10-month follow-up TTE scan revealed no thrombus recurrence and treatment with warfarin and prednisolone was continued. PMID:27226921

  9. Laser-Activated Shape Memory Polymer Microactuator for Thrombus Removal Following Ischemic Stroke: Preliminary In Vitro Analysis

    SciTech Connect

    Small, W; Metzger, M F; Wilson, T S; Maitland, D J

    2004-09-23

    Due to the narrow (3-hour) treatment window for effective use of the thrombolytic drug recombinant tissue-type plasminogen activator (rt-PA), there is a need to develop alternative treatments for ischemic stroke. We are developing an intravascular device for mechanical thrombus removal using shape memory polymer (SMP). We propose to deliver the SMP microactuator in its secondary straight rod form (length = 4 cm, diameter = 350 {micro}m) through a catheter distal to the vascular occlusion. The microactuator, which is mounted on the end of an optical fiber, is then transformed into its primary corkscrew shape by laser heating (diode laser, {lambda} = 800 nm) above its soft phase glass transition temperature (T{sub gs} = 55 C). Once deployed, the microactuator is retracted and the captured thrombus is removed to restore blood flow. The SMP is doped with indocyanine green (ICG) dye to increase absorption of the laser light. Successful deployment of the microactuator depends on the optical properties of the ICG-doped SMP and the optical coupling efficiency of the interface between the optical fiber and the SMP. Spectrophotometry, thermal imaging, and computer simulation aided the initial design effort and continue to be useful tools for optimization of the dye concentration and laser power. Thermomechanical testing was performed to characterize the elastic modulus of the SMP. We have demonstrated laser-activation of the SMP microactuator in air at room temperature, suggesting this concept is a promising therapeutic alternative to rt-PA.

  10. Acromegaly With Cardiomyopathy, Cardiac Thrombus and Hemorrhagic Cerebral Infarct: A Case Report of Therapeutic Dilemma With Review of Literature

    PubMed Central

    Mendoza, Erick; Malong, Chandy Lou; Tanchee-Ngo, Mary Jane; Mercado-Asis, Leilani

    2015-01-01

    Introduction: Cardiomyopathy with congestive heart failure (CHF) is a rare complication of growth hormone (GH)-secreting pituitary adenoma occurring in 3% of cases. We report a case of acromegaly complicated not only by CHF but also by the presence of intracardiac thrombus and cardioembolic stroke with hemorrhagic formation. Case Presentation: A 46-year-old Filipino female presented with amenorrhea, progressive coarsening of facial features, deepening of voice and enlargement of digits. She experienced easy fatigability, orthopnea and bipedal edema. The cardiac apex beat was sustained and displaced. Growth hormone was nonsuppressible. Cranial magnetic resonance imaging showed pituitary macroadenoma with hemorrhage. Incidentally, there was a left frontal lobe cortical infarct with hemorrhagic component. The echocardiogram demonstrated cardiomyopathic changes with a left ventricular thrombus. Conclusions: The primary treatment for GH-producing adenoma is surgery; however, this patient has high surgical risk from her severe cardiomyopathy. Radiotherapy poses a greater risk because of increased cerebrovascular mortality. Somatostatin receptor ligands are significantly associated with improvement of cardiovascular and hemodynamic parameters. Dopamine agonists must be considered regardless of prolactin level and immunostaining. The risks and benefits of any treatment must be emphasized in the presence of conflicting clinical features such as in the case reported. PMID:25926851

  11. The differential effects of aspirin on platelets, leucocytes and vascular endothelium in an in vivo model of thrombus formation.

    PubMed

    Nagamatsu, Y; Tsujioka, Y; Hashimoto, M; Giddings, J C; Yamamoto, J

    1999-02-01

    Unanswered questions remain with regard to the therapeutic use of aspirin and the selective inhibition of thromboxane A2 and prostacyclin in platelets and endothelial cells. In the present study, the effects of aspirin on platelets and endothelial cells in vivo were examined using a helium-neon (He-Ne) laser-induced thrombosis model. Single intravenous injections of aspirin at concentrations of more than 0.5 mg/kg body weight mediated a dose dependent inhibition of thrombus formation in arterioles but not in venules. This antithrombotic effect was optimum after 15 min and declined after 90 min. Potent antithrombotic activity in arterioles was manifest at doses of 2.5 mg/kg to 50 mg/kg, and initial inhibition of thrombogenesis in vivo was most pronounced at high doses. Oral aspirin also inhibited thrombus formation in arterioles but not in venules, although the antithrombotic effects were delayed and prolonged. Maximum inhibition of ex vivo, collagen induced platelet aggregation by aspirin was observed approximately 180 min after intravenous injection. The results demonstrated that, although aspirin might have differential effects on platelets and endothelial cells, potent antithrombotic activity was manifest in arterioles at all concentrations. The findings suggest that the concept of the aspirin dilemma might be ignored for therapeutic purposes in many clinical circumstances. The antithrombotic effects of aspirin were unchanged in granulocyte-depleted animals, indicating that leucocyte-related mechanisms including neutrophil superoxide anion production did not modulate the potency of aspirin in this model. PMID:10197261

  12. Carotid thrombus formation and extension during anticoagulation: a case report of large vessel disease and hypercoagulable state in systemic sclerosis.

    PubMed

    Renard, Dimitri; Heroum, Chérif

    2007-06-01

    Systemic sclerosis (SSc) is an autoimmune multisystem disorder of connective tissue characterized by widespread vascular lesions and fibrosis. Limited cutaneous systemic sclerosis (lcSSc) and diffuse cutaneous systemic sclerosis (dsSSC) are both subsets of SSc. The vascular component of SSc is an important part of the disease. Especially Raynaud's phenomenon and microcirculatory abnormalities are well recognized. Enhanced coagulation pathways, decreased fibrinolysis, and endothelial dysfunction probably contribute to vascular events in SSc. Macrovascular disease is not recognized as a major feature of SSc. However, several studies report an increase in large vessel disease and mortality rate attributable to cardiovascular causes. We present a patient with lcSSc with an acute embolic stroke due to a large carotid thrombus. A hypercoagulable state was suspected because of thrombus formation during oral anticoagulation and extension during intravenous heparin treatment. This is one of the few reports of large vessel disease in systemic sclerosis. The hypercoagulable state may be related to systemic sclerosis. PMID:17710842

  13. Thrombus-Targeted Theranostic Microbubbles: A New Technology towards Concurrent Rapid Ultrasound Diagnosis and Bleeding-free Fibrinolytic Treatment of Thrombosis

    PubMed Central

    Wang, Xiaowei; Gkanatsas, Yannik; Palasubramaniam, Jathushan; Hohmann, Jan David; Chen, Yung Chih; Lim, Bock; Hagemeyer, Christoph E; Peter, Karlheinz

    2016-01-01

    Rationale: Myocardial infarction and stroke are leading causes of morbidity/mortality. The typical underlying pathology is the formation of thrombi/emboli and subsequent vessel occlusion. Systemically administered fibrinolytic drugs are the most effective pharmacological therapy. However, bleeding complications are relatively common and this risk as such limits their broader use. Furthermore, a rapid non-invasive imaging technology is not available. Thereby, many thrombotic events are missed or only diagnosed when ischemic damage has already occurred. Objective: Design and preclinical testing of a novel 'theranostic' technology for the rapid non-invasive diagnosis and effective, bleeding-free treatment of thrombosis. Methods and Results: A newly created, innovative theranostic microbubble combines a recombinant fibrinolytic drug, an echo-enhancing microbubble and a recombinant thrombus-targeting device in form of an activated-platelet-specific single-chain antibody. After initial in vitro proof of functionality, we tested this theranostic microbubble both in ultrasound imaging and thrombolytic therapy using a mouse model of ferric-chloride-induced thrombosis in the carotid artery. We demonstrate the reliable highly sensitive detection of in vivo thrombi and the ability to monitor their size changes in real time. Furthermore, these theranostic microbubbles proofed to be as effective in thrombolysis as commercial urokinase but without the prolongation of bleeding time as seen with urokinase. Conclusions: We describe a novel theranostic technology enabling simultaneous diagnosis and treatment of thrombosis, as well as monitoring of success or failure of thrombolysis. This technology holds promise for major progress in rapid diagnosis and bleeding-free thrombolysis thereby potentially preventing the often devastating consequences of thrombotic disease in many patients. PMID:27022419

  14. Nanometer-Size Iron Sulfides Biomineralized by a Deep-Sea Hydrothermal Vent Gastropod in Cooperation with Endosymbiotic Sulfate-Reducing Bacteria

    NASA Astrophysics Data System (ADS)

    Suzuki, Y.; Kogure, T.; Takai, K.; Tsuchida, S.; Nealson, K. H.; Horikoshi, K.

    2003-12-01

    The _gscaly-foot_h gastropod has been discovered only from a deep-sea hydrothermal field in the Central Indian Ridge among the global Mid Ocean Ridges (MOR) and found to be peculiar, because it has scale-shaped sclerites composed of hard proteins and iron sulfides that covered the sides of the foot. As the product and mechanism of the iron sulfide biomineralization have not been elucidated in any details, yet, we conducted crystallographic and molecular phylogenetic characterizations of the sclerites._@It was revealed that nanometer-scale (1) mackinawite (FeS) + greigite (Fe3S4), (2) pyrite (FeS2) and (3) mackinawite formed in distinct strata from the outer to inner parts of the sclerites, respectively. This study demonstrated for the first time that pyrite occurred in nature as exceedingly small crystalline nanoparticles (around 3 nm in diameter) and to grow via the aggregation-based pathway._@Phylogenetic analyses based on 16S rRNA and dissimilatory sulfite reductase (DSR) genes detected predominant occurrence of bacteria that have the sequences of both genes closely related to sulfate-reducing Desulfobulbus spp. Fluorescence in-situ hybridization analysis using a probe specific to the retrieved 16S rRNA gene sequences of the Desulfobulbus-related bacteria revealed the localized occurrence of the bacteria in the most inner part of the sclerites, which represents a novel structural integration between bacteria and metazoans. The results strongly suggested the potential contribution of endosymbiotic SRB to formation of stratified nanometer-scale iron sulfides inside the gastropod_fs scaly. As mackinawite that is easily oxidized under slightly oxic conditions and persisted, pyrite seems to have formed via the strictly anoxic pathway. The results presented here may provide aid in deciphering important, but still partially understood formation mechanisms and biochemical and geochemical roles of iron sulfides.

  15. Platelet-derived ERp57 mediates platelet incorporation into a growing thrombus by regulation of the αIIbβ3 integrin

    PubMed Central

    Wang, Lu; Zhou, Junsong; Ahmad, Syed S.; Mutus, Bulent; Garbi, Natalio; Hämmerling, Günter; Liu, Junling

    2013-01-01

    The platelet protein disulfide isomerase called ERp57 mediates platelet aggregation, but its role in thrombus formation is unknown. To determine the specific role of platelet-derived ERp57 in hemostasis and thrombosis, we generated a megakaryocyte/platelet-specific knockout. Despite normal platelet counts and platelet glycoprotein expression, mice with ERp57-deficient platelets had prolonged tail-bleeding times and thrombus occlusion times with FeCl3-induced carotid artery injury. Using a mesenteric artery thrombosis model, we found decreased incorporation of ERp57-deficient platelets into a growing thrombus. Platelets lacking ERp57 have defective activation of the αIIbβ3 integrin and platelet aggregation. The defect in aggregation was corrected by the addition of exogenous ERp57, implicating surface ERp57 in platelet aggregation. Using mutants of ERp57, we demonstrate the second active site targets a platelet surface substrate to potentiate platelet aggregation. Binding of Alexa 488−labeled ERp57 to thrombin-activated and Mn2+-treated platelets lacking β3 was decreased substantially, suggesting a direct interaction of ERp57 with αIIbβ3. Surface expression of ERp57 protein and activity in human platelets increased with platelet activation, with protein expression occurring in a physiologically relevant time frame. In conclusion, platelet-derived ERp57 directly interacts with αIIbβ3 during activation of this receptor and is required for incorporation of platelets into a growing thrombus. PMID:24030382

  16. Platelet-derived ERp57 mediates platelet incorporation into a growing thrombus by regulation of the αIIbβ3 integrin.

    PubMed

    Wang, Lu; Wu, Yi; Zhou, Junsong; Ahmad, Syed S; Mutus, Bulent; Garbi, Natalio; Hämmerling, Günter; Liu, Junling; Essex, David W

    2013-11-21

    The platelet protein disulfide isomerase called ERp57 mediates platelet aggregation, but its role in thrombus formation is unknown. To determine the specific role of platelet-derived ERp57 in hemostasis and thrombosis, we generated a megakaryocyte/platelet-specific knockout. Despite normal platelet counts and platelet glycoprotein expression, mice with ERp57-deficient platelets had prolonged tail-bleeding times and thrombus occlusion times with FeCl3-induced carotid artery injury. Using a mesenteric artery thrombosis model, we found decreased incorporation of ERp57-deficient platelets into a growing thrombus. Platelets lacking ERp57 have defective activation of the αIIbβ3 integrin and platelet aggregation. The defect in aggregation was corrected by the addition of exogenous ERp57, implicating surface ERp57 in platelet aggregation. Using mutants of ERp57, we demonstrate the second active site targets a platelet surface substrate to potentiate platelet aggregation. Binding of Alexa 488-labeled ERp57 to thrombin-activated and Mn(2+)-treated platelets lacking β3 was decreased substantially, suggesting a direct interaction of ERp57 with αIIbβ3. Surface expression of ERp57 protein and activity in human platelets increased with platelet activation, with protein expression occurring in a physiologically relevant time frame. In conclusion, platelet-derived ERp57 directly interacts with αIIbβ3 during activation of this receptor and is required for incorporation of platelets into a growing thrombus. PMID:24030382

  17. Reduced size fuel cell for portable applications

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram R. (Inventor); Valdez, Thomas I. (Inventor); Clara, Filiberto (Inventor); Frank, Harvey A. (Inventor)

    2004-01-01

    A flat pack type fuel cell includes a plurality of membrane electrode assemblies. Each membrane electrode assembly is formed of an anode, an electrolyte, and an cathode with appropriate catalysts thereon. The anode is directly into contact with fuel via a wicking element. The fuel reservoir may extend along the same axis as the membrane electrode assemblies, so that fuel can be applied to each of the anodes. Each of the fuel cell elements is interconnected together to provide the voltage outputs in series.

  18. Comparison of the usefulness of enoxaparin versus warfarin for prevention of left ventricular mural thrombus after anterior wall acute myocardial infarction.

    PubMed

    White, Derek C; Grines, Cindy L; Grines, Lorelei L; Marcovitz, Pamela; Messenger, John; Schreiber, Theodore

    2015-05-01

    Left ventricular (LV) thrombus is one of the most common complications in patients with anterior acute myocardial infarction (AMI) and LV dysfunction. Although anticoagulation is frequently prescribed, data regarding the appropriate drug, duration, risks, and effect on echocardiographic indices of thrombus are lacking. Moreover, given the difficulty in obtaining adequate anticoagulation with warfarin, it is possible that short-term treatment with a more predictable agent would be effective. We randomized 60 patients at high risk of developing LV mural thrombus (anterior acute myocardial infarction with Q waves and ejection fraction≤40%) to receive either enoxaparin 1 mg/kg (maximum 100 mg) subcutaneously every 12 hours for 30 days or traditional anticoagulation (intravenous heparin followed by oral warfarin for 3 months). Clinical evaluations and transthoracic echocardiograms were obtained at baseline, in-hospital, and at 3.5 months. There were no differences between the groups regarding baseline demographics, acute echocardiographic findings, and in-hospital outcomes. The length of hospital stay tended to be shorter for the enoxaparin group (4.6 vs 5.6; p=0.066) and the corresponding hospital costs ($25,837 vs $34,666; p=0.18). At 3 months, bleeding and thromboembolic events were rare and similar between enoxaparin and warfarin groups. Although more patients had probable mural thrombus in the enoxaparin group compared with warfarin at 3.5 months (15% vs 4%; p=0.35), this was not significantly different. In conclusion, the use of enoxaparin tends to shorten hospitalization and lower cost of care. However, at 3.5 months, there appears to be numerically higher (but statistically insignificant) rates of LV thrombus in the enoxaparin group.

  19. Heterologous over-expression of ACC SYNTHASE8 (ACS8) in Populus tremula x P. alba clone 717-1B4 results in elevated levels of ethylene and induces stem dwarfism and reduced leaf size through separate genetic pathways.

    PubMed

    Plett, Jonathan M; Williams, Martin; LeClair, Gaetan; Regan, Sharon; Beardmore, Tannis

    2014-01-01

    Plant height is an important agronomic and horticultural trait that impacts plant productivity, durability and esthetic appeal. A number of the plant hormones such as gibberellic acid (GA), auxin and ethylene have been linked to control of plant architecture and size. Reduction in GA synthesis and auxin transport result in dwarfism while ethylene may have a permissive or repressive effect on tissue growth depending upon the age of plant tissues or the environmental conditions considered. We describe here an activation-tagged mutant of Populus tremula x P. alba clone 717-1B4 identified from 2000 independent transgenic lines due to its significantly reduced growth rate and smaller leaf size. Named dwarfy, the phenotype is due to increased expression of PtaACC SYNTHASE8, which codes for an enzyme in the first committed step in the biosynthesis of ethylene. Stems of dwarfy contain fiber and vessel elements that are reduced in length while leaves contain fewer cells. These morphological differences are linked to PtaACS8 inducing different transcriptomic programs in the stem and leaf, with genes related to auxin diffusion and sensing being repressed in the stem and genes related to cell division found to be repressed in the leaves. Altogether, our study gives mechanistic insight into the genetics underpinning ethylene-induced dwarfism in a perennial model organism. PMID:25414707

  20. Heterologous over-expression of ACC SYNTHASE8 (ACS8) in Populus tremula x P. alba clone 717-1B4 results in elevated levels of ethylene and induces stem dwarfism and reduced leaf size through separate genetic pathways

    PubMed Central

    Plett, Jonathan M.; Williams, Martin; LeClair, Gaetan; Regan, Sharon; Beardmore, Tannis

    2014-01-01

    Plant height is an important agronomic and horticultural trait that impacts plant productivity, durability and esthetic appeal. A number of the plant hormones such as gibberellic acid (GA), auxin and ethylene have been linked to control of plant architecture and size. Reduction in GA synthesis and auxin transport result in dwarfism while ethylene may have a permissive or repressive effect on tissue growth depending upon the age of plant tissues or the environmental conditions considered. We describe here an activation-tagged mutant of Populus tremula x P. alba clone 717-1B4 identified from 2000 independent transgenic lines due to its significantly reduced growth rate and smaller leaf size. Named dwarfy, the phenotype is due to increased expression of PtaACC SYNTHASE8, which codes for an enzyme in the first committed step in the biosynthesis of ethylene. Stems of dwarfy contain fiber and vessel elements that are reduced in length while leaves contain fewer cells. These morphological differences are linked to PtaACS8 inducing different transcriptomic programs in the stem and leaf, with genes related to auxin diffusion and sensing being repressed in the stem and genes related to cell division found to be repressed in the leaves. Altogether, our study gives mechanistic insight into the genetics underpinning ethylene-induced dwarfism in a perennial model organism. PMID:25414707

  1. [Fulminant myocarditis causing severe left heart failure and massive thrombus formation following cardiac tamponade: a case report].

    PubMed

    Miyamoto, Koji; Yasuda, Satoshi; Noguchi, Teruo; Tanimoto, Takashi; Kakuchi, Hiroyuki; Morii, Isao; Kawamura, Atsushi; Nakatani, Takeshi; Nonogi, Hiroshi; Goto, Yoichi; Miyazaki, Shunichi

    2005-07-01

    A woman aged middle thirties presented with common cold-like symptoms, and was hospitalized due to hypotension and tachycardia. Echocardiography revealed pericardial effusion and preserved left ventricular fractional shortening (28%). Cardiac index, pulmonary capillary wedge and right atrial pressure were 1.8 l/min/m2, 15 and 13 mmHg, respectively. After drainage of pericardial effusion, cardiac index increased to 3.4 l/min/m2. On the fifth hospital day, left ventricular dysfunction developed (fractional shortening: 16%, cardiac index: 1.5 l/min/m2, pulmonary capillary wedge pressure: 18 mmHg, right atrial pressure: 12 mmHg), so percutaneous cardiopulmonary support was introduced. However, the heart failed in asystole and the cavity was occupied by massive thrombus, probably related to heparin-induced thrombocytopenia. This case of fulminant myocarditis passed through various clinical features of heart failure. She died on the 12th hospital day.

  2. Acute free-floating carotid artery thrombus causing stroke in a young patient: unique etiology and management using endovascular approach.

    PubMed

    Tan, Ai Peng; Taneja, Manish; Seah, Boon Heng; Leong, Hoe Nam; Venketasubramanian, Narayanaswamy

    2014-01-01

    Atherosclerotic disease accounts for 20%-30% of strokes in the general population. In young adults, it is an unexpected event and its causes involve diverse pathologies. Herein, we describe a unique case of acute embolic stroke in a young adult patient due to the presence of a large clot in the right common and internal carotid arteries, as a result of an extrinsic cause. Surgical clot retrieval was considered unsafe at that point in time in view of the active inflammatory changes surrounding the affected vessels. This was eventually treated with a novel endovascular technique, a unique alternative to open surgery, with excellent clinical outcome. To our knowledge, the penumbra system has never been used for thrombus removal in a nonacute setting. PMID:25440371

  3. AngioVac Aspiration for Paradoxical Emboli Protection through a Fenestrated Fontan During Central Venous Thrombus Manipulation

    SciTech Connect

    Al-Hakim, Ramsey; Patel, Komal; Moriarty, John M.

    2015-06-15

    This case reports describes a 39-year-old female with a history of surgically repaired hypoplastic left heart syndrome who presented with a left peripherally inserted central catheter (PICC) with associated large volume subclavian and brachiocephalic vein thrombus. Due to the presence of a right-to-left shunt via a fenestrated Fontan, there was clinical concern for a paradoxical embolism during removal of the PICC. The AngioVac aspiration system was successfully utilized to aspirate thromboemboli from the level of the proximal Glenn shunt during manipulation and removal of the PICC. This is the first reported case to demonstrate the safe and effective use of the AngioVac aspiration system for protection of paradoxical emboli through a cardiac right-to-left shunt during a procedure at high risk for thromboembolism.

  4. Successful Percutaneous Coronary Intervention through a Severely Bent Artificial Ascending Aorta Using the DIO Thrombus Aspiration Catheter.

    PubMed

    Fujikake, Akinori; Komatsu, Takaaki; Taguchi, Isao

    2016-01-01

    A 66-year-old man was admitted to our institute because of chest pain. He had undergone replacement of the ascending aorta due to aortic dissection 9 years previously. We made a diagnosis of acute coronary syndrome, and coronary artery angiography was performed. Although the right coronary artery was successfully cannulated, a severe bend of the artificial aorta made it very difficult to advance the catheter into the left coronary artery. Ultimately, a DIO thrombus aspiration catheter was used to enter the left coronary artery, and a stent was implanted successfully. The DIO catheter is very useful when the selection of a guiding catheter is complicated, such as in the case of severe vessel tortuosity or a bend of the ascending aorta. PMID:27516912

  5. Disseminated Intravascular Coagulation with Congestive Heart Failure and Left Ventricular Thrombus: A Case Report with Literature Review of 7 Cases

    PubMed Central

    Belov, Dmitri; Lyubarova, Radmila; Fein, Steven; Torosoff, Mikhail

    2015-01-01

    Patient: Male, 55 Final Diagnosis: Disseminated intravascular coagulation Symptoms: Leg pain • short of breath • swelling legs Medication: — Clinical Procedure: — Specialty: Cardiology Objective: Unusual clinical course Background: Coagulation abnormalities can accompany acute congestive heart failure (CHF). However, disseminated intravascular coagulation (DIC) is rarely documented in such patients. DIC is characterized by generalized excessive activation of coagulation pathways followed by their depletion with secondary activation of anticoagulation and fibrinolysis. Treatment of the cause is an integral part of management of DIC; thus, recognition of the cause is critical. Case Report: A 55-year-old previously healthy man presented with breathlessness, swelling of both legs, and left leg pain. His physical exam result was consistent with decompensated heart failure. Further testing revealed multiple deep venous thrombi in the upper and lower extremities, arterial occlusion in the left popliteal artery, and an unusual cyst-like left ventricular thrombus. His laboratory evaluation was consistent with severe acute DIC. The patient was managed aggressively with diuretics, transfusions of platelets, and cryoprecipitate and was subsequently anticoagulated. His platelet count and coagulation parameters normalized and coronary angiography did not reveal any obstructive lesions. On day 22, an echocardiogram revealed and MRI confirmed that the intracardiac thrombus had disappeared. He underwent revascularization of the left leg and was successfully discharged from the hospital. Conclusions: Severe biventricular non-ischemic cardiac dysfunction with intra-cardiac thrombi should be considered in patients presenting with DIC. In addition to anticoagulation, treatment of underlying heart failure is critical in such cases. PMID:25637329

  6. Trivalent methylated arsenical-induced phosphatidylserine exposure and apoptosis in platelets may lead to increased thrombus formation

    SciTech Connect

    Bae, Ok-Nam; Lim, Kyung-Min; Chung, Jin-Ho

    2009-09-01

    Trivalent methylated metabolites of arsenic, monomethylarsonous acid (MMA{sup III}) and dimethylarsinous acid (DMA{sup III}), have been found highly reactive and toxic in various cells and in vivo animal models, suggesting their roles in the arsenic-associated toxicity. However, their effects on cardiovascular system including blood cells, one of the most important targets for arsenic toxicity, remain poorly understood. Here we found that MMA{sup III} and DMA{sup III} could induce procoagulant activity and apoptosis in platelets, which play key roles in the development of various cardiovascular diseases (CVDs) through excessive thrombus formation. In freshly isolated human platelets, treatment of MMA{sup III} resulted in phosphatidylserine (PS) exposure, a hallmark of procoagulant activation, accompanied by distinctive apoptotic features including mitochondrial membrane potential disruption, cytochrome c release, and caspase-3 activation. These procoagulant activation and apoptotic features were found to be mediated by the depletion of protein thiol and intracellular ATP, and flippase inhibition by MMA{sup III}, while the intracellular calcium increase or reactive oxygen species generation was not involved. Importantly, increased platelet procoagulant activity by MMA{sup III} resulted in enhanced blood coagulation and excessive thrombus formation in a rat in vivo venous thrombosis model. DMA{sup III} also induced PS-exposure with apoptotic features mediated by protein thiol depletion, which resulted in enhanced thrombin generation. In summary, we believe that this study provides an important evidence for the role of trivalent methylated arsenic metabolites in arsenic-associated CVDs, giving a novel insight into the role of platelet apoptosis in toxicant-induced cardiovascular toxicity.

  7. Thrombus imaging in a primate model with antibodies specific for an external membrane protein of activated platelets

    SciTech Connect

    Palabrica, T.M.; Furie, B.C.; Konstam, M.A.; Aronovitz, M.J.; Connolly, R.; Brockway, B.A.; Ramberg, K.L.; Furie, B.

    1989-02-01

    The activated platelet is a potential target for the localization of thrombi in vivo since, after stimulation and secretion of granule contents, activated platelets are concentrated at sites of blood clot formation. In this study, we used antibodies specific for a membrane protein of activated platelets to detect experimental thrombi in an animal model. PADGEM (platelet activation-dependent granule-external membrane protein), a platelet alpha-granule membrane protein, is translocated to the plasma membrane during platelet activation and granule secretion. Since PADGEM is internal in unstimulated platelets, polyclonal anti-PADGEM and monoclonal KC4 antibodies do not bind to circulating resting platelets but do interact with activated platelets. Dacron graft material incubated with radiolabeled KC4 or anti-PADGEM antibodies in the presence of thrombin-activated platelet-rich plasma bound most of the antibody. Imaging experiments with 123I-labeled anti-PADGEM in baboons with an external arterial-venous Dacron shunt revealed rapid uptake in the thrombus induced by the Dacron graft; control experiments with 123I-labeled nonimmune IgG exhibited minimal uptake. Deep venous thrombi, formed by using percutaneous balloon catheters to stop blood flow in the femoral vein of baboons, were visualized with 123I-labeled anti-PADGEM. Thrombi were discernible against blood pool background activity without subtraction techniques within 1 hr. No target enhancement was seen with 123I-labeled nonimmune IgG. 123I-labeled anti-PADGEM cleared the blood pool with an initial half-disappearance time of 6 min and did not interfere with hemostasis. These results indicate that radioimmunoscintigraphy with anti-PADGEM antibodies can visualize thrombi in baboon models and is a promising technique for clinical thrombus detection in humans.

  8. Expression of human apolipoprotein A-I in transgenic mice results in reduced plasma levels of murine apolipoprotein A-I and the appearance of two new high density lipoprotein size subclasses.

    PubMed

    Rubin, E M; Ishida, B Y; Clift, S M; Krauss, R M

    1991-01-15

    In Western societies high density lipoprotein (HDL) levels correlate inversely with the risk for coronary heart disease. The primary protein component of both human and mouse HDL is apolipoprotein A-I (apoAI), which comprises greater than 70% of HDL protein and 30% of HDL mass. Human HDLs include particles of several distinct size subpopulations, whereas HDLs from inbred C57BL/6 mice contain a single population of particles. To study the regulation of apoAI expression and its role in HDL assembly, we created transgenic C57BL/6 mice containing the human apoAI gene. Two independent lines of transgenic mice with approximately twice the normal plasma levels of total apoAI were studied. The level of mouse apoAI is reduced greater than 4-fold in both transgenic lines, comprising only 4% of total plasma apoAI levels in one transgenic line and 13% in the other. We demonstrate that the mechanism responsible for the decrease in mouse apoAI is posttranscriptional. Parallel to the replacement of mouse with human apoAI, the single HDL species normally present in the plasma of C57BL/6 is replaced by two HDL subclasses similar in size to human HDL2b and HDL3a. The changes in murine apolipoprotein levels and HDL subclass size are inherited by all transgenic offspring of the two founder animals. These results suggest a dominant role of apoAI in determining the HDL particle size distribution and a mechanism involving expression of human apoAI transgenes that alters the plasma levels of mouse apoAI.

  9. Dose-volume histogram parameters of high-dose-rate brachytherapy for Stage I-II cervical cancer (≤4cm) arising from a small-sized uterus treated with a point A dose-reduced plan.

    PubMed

    Nakagawa, Akiko; Ohno, Tatsuya; Noda, Shin-ei; Kubo, Nobuteru; Kuwako, Keiko; Saitoh, Jun-Ichi; Nakano, Takashi

    2014-07-01

    We investigated the rectal dose-sparing effect and tumor control of a point A dose-reduced plan in patients with Stage I-II cervical cancer (≤4 cm) arising from a small-sized uterus. Between October 2008 and August 2011, 19 patients with Stage I-II cervical cancer (≤4 cm) were treated with external beam radiotherapy (EBRT) for the pelvis and CT-guided brachytherapy. Seven patients were treated with brachytherapy with standard loading of source-dwell positions and a fraction dose of 6 Gy at point A (conventional brachy-plan). The other 12 patients with a small uterus close to the rectum or small intestine were treated with brachytherapy with a point A dose-reduction to match D2cc of the rectum and <6 Gy as the dose constraint ('point A dose-reduced plan') instead of the 6-Gy plan at point A ('tentative 6-Gy plan'). The total doses from EBRT and brachytherapy were added up and normalized to a biological equivalent dose of 2 Gy per fraction (EQD2). The median doses to the high-risk clinical target volume (HR-CTV) D90 in the conventional brachy-plan, tentative 6-Gy plan and point A dose-reduced plan were 62 GyEQD2, 80 GyEQD2 and 64 GyEQD2, respectively. The median doses of rectal D2cc in the corresponding three plans were 42 GyEQD2, 62 GyEQD2 and 51 GyEQD2, respectively. With a median follow-up period of 35 months, three patients developed Grade-1 late rectal complications and no patients developed local recurrence. Our preliminary results suggested that CT-guided brachytherapy using an individualized point A dose-reduced plan might be useful for reducing late rectal complications while maintaining primary tumor control.

  10. Rationale and design of a study exploring the efficacy of once-daily oral rivaroxaban (X-TRA) on the outcome of left atrial/left atrial appendage thrombus in nonvalvular atrial fibrillation or atrial flutter and a retrospective observational registry providing baseline data (CLOT-AF).

    PubMed

    Lip, Gregory Y H; Hammerstingl, Christoph; Marin, Francisco; Cappato, Riccardo; Meng, Isabelle Ling; Kirsch, Bodo; Morandi, Eolo; van Eickels, Martin; Cohen, Ariel

    2015-04-01

    There are still many unresolved issues concerning patient outcomes and prognostic factors in patients with atrial fibrillation (AF) and left atrial/left atrial appendage (LA/LAA) thrombi. Rivaroxaban (Xarelto®), a potent and highly selective oral, direct factor Xa inhibitor, is a new therapeutic option in this setting. The planned study program will consist of a prospective interventional study (X-TRA) and a retrospective observational registry (CLOT-AF). The primary objective of the X-TRA study is to explore the efficacy of rivaroxaban in the treatment of LA/LAA thrombi in patients with nonvalvular AF or atrial flutter, scheduled to undergo cardioversion or AF ablation, in whom an LA/LAA thrombus has been found on transesophageal echocardiography (TEE) before the procedure. The primary end point is the complete LA/LAA thrombus resolution rate at 6 weeks of end of treatment confirmed by TEE. The secondary objectives are to describe categories of thrombus outcome in patients (resolved, reduced, unchanged, larger, or new) confirmed on TEE at the end of treatment (after 6 weeks of treatment), incidence of the composite of stroke and noncentral nervous system systemic embolism at the end of treatment and during follow-up, and incidence of all bleeding at the end of treatment and during follow-up. The objective of the CLOT-AF registry is to provide retrospective thrombus-related patient outcome data after standard-of-care anticoagulant treatment in patients with nonvalvular AF or atrial flutter, who have TEE-documented LA/LAA thrombi. The data will be used as a reference for the prospective X-TRA study. In conclusion, X-TRA and CLOT-AF will provide some answers to the many unresolved issues concerning patient outcomes and prognostic factors in patients with AF and LAA thrombi. Results from this study program would provide the first prospective interventional study (X-TRA) and a large international retrospective observational registry (CLOT-AF) on the prevalence and

  11. The effectiveness of antioxidant vitamins C and E in reducing myocardial infarct size in patients subjected to percutaneous coronary angioplasty (PREVEC Trial): study protocol for a pilot randomized double-blind controlled trial

    PubMed Central

    2014-01-01

    Background Acute myocardial infarction (AMI) is the leading cause of mortality worldwide. Oxidative stress has been involved in the ischemia-reperfusion injury in AMI. It has been suggested that reperfusion accounts for up to 50% of the final size of a myocardial infarct, a part of the damage likely to be prevented.Therefore, we propose that antioxidant reinforcement through vitamins C and E supplementation should protect against the ischemia-reperfusion damage, thus decreasing infarct size. The PREVEC Trial (Prevention of reperfusion damage associated with percutaneous coronary angioplasty following acute myocardial infarction) seeks to evaluate whether antioxidant vitamins C and E reduce infarct size in patients subjected to percutaneous coronary angioplasty after AMI. Methods/Design This is a randomized, 1:1, double-blind, placebo-controlled clinical trial. The study takes place at two centers in Chile: University of Chile Clinical Hospital and San Borja Arriarán Clinical Hospital. The subjects will be 134 adults with acute myocardial infarction with indication for percutaneous coronary angioplasty. This intervention is being performed as a pilot study, involving high-dose vitamin C infusion plus oral administration of vitamin E (Vitamin-treatment group) or placebo (Control group) during the angioplasty procedure. Afterward, the Vitamin-treatment group receives oral doses of vitamins C and E, and the Control group receives placebo for 84 days after coronary angioplasty. Primary outcome is infarct size, assessed by cardiac magnetic resonance (CMR), measured 6 and 84 days after coronary angioplasty. Secondary outcomes are ejection fraction, measured 6 and 84 days after coronary angioplasty with CMR, and biomarkers for oxidative stress, antioxidant status, heart damage, and inflammation, which will be measured at baseline, at the onset of reperfusion, 6 to 8 hours after revascularization, and at hospital discharge. Discussion The ischemia-reperfusion event

  12. Class Size.

    ERIC Educational Resources Information Center

    Ellis, Thomas I.

    1985-01-01

    After a brief introduction identifying current issues and trends in research on class size, this brochure reviews five recent studies bearing on the relationship of class size to educational effectiveness. Part 1 is a review of two interrelated and highly controversial "meta-analyses" or statistical integrations of research findings on class size,…

  13. Sub-10 μm grain size, Ba1-xCaxTi0.9Zr0.1O3 (x = 0.10 and x = 0.15) piezoceramics processed using a reduced thermal treatment

    NASA Astrophysics Data System (ADS)

    Reyes-Montero, A.; Pardo, L.; López-Juárez, R.; González, A. M.; Rea-López, S. O.; Cruz, M. P.; Villafuerte-Castrejón, M. E.

    2015-06-01

    The solid-state synthesis of Ba1-xCaxTi0.9Zr0.1O3 (x = 0.10, 0.15) (BCTZ) powder and the processing method of ceramics, by the use of reduced synthesis time and temperature (1250 °C for 2 h), are reported. Homogeneous and dense (≥95%) ceramic microstructures with sub-10 μm grain size were obtained under all sintering conditions. A comparative study of their ferro-piezoelectric properties as a function of sintering temperatures is presented. The study shows the role of the grain size effect for improving both piezoelectric and ferroelectric properties of these materials. With an increase of the sintering temperature, grain growth was promoted; therefore, higher ferro-piezoelectric values were obtained (at 1400 °C, for x = 0.10: d33 = 300 pC/N, {{d}31}=-150 pC/N, kp = 48% for x = 0.15: d33 = 410 pC/N, d31 =-154 pC/N, kp = 50%). In addition, a diffuse phase transition is observed in these BCTZ ceramics with a Curie temperature near 100 °C at 1 kHz.

  14. Subcellular Size

    PubMed Central

    Marshall, Wallace F.

    2016-01-01

    All of the same conceptual questions about size in organisms apply equally at the level of single cells. What determines the size, not only of the whole cell, but of all its parts? What ensures that subcellular components are properly proportioned relative to the whole cell? How does alteration in organelle size affect biochemical function? Answering such fundamental questions requires us to understand how the size of individual organelles and other cellular structures is determined. Knowledge of organelle biogenesis and dynamics has advanced rapidly in recent years. Does this knowledge give us enough information to formulate reasonable models for organelle size control, or are we still missing something? PMID:25957302

  15. Selective inhibition of OCTN2 is more effective than inhibition of gamma-butyrobetaine dioxygenase to decrease the availability of l-carnitine and to reduce myocardial infarct size.

    PubMed

    Liepinsh, Edgars; Makrecka, Marina; Kuka, Janis; Cirule, Helena; Makarova, Elina; Sevostjanovs, Eduards; Grinberga, Solveiga; Vilskersts, Reinis; Lola, Daina; Loza, Einars; Stonans, Ilmars; Pugovics, Osvalds; Dambrova, Maija

    2014-07-01

    l-Carnitine is a cofactor in the energy metabolism pathways where it drives the uptake and oxidation of long chain fatty acids (LCFA) by mitochondria. LCFA lipotoxicity causes mitochondrial damage and results in an insufficient energy supply and a decrease in l-carnitine content limits LCFA flux and protects mitochondria. Here, we tested whether the inhibition of GBB dioxygenase (BBOX) or organic cation transporter 2 (OCTN2) is the most effective strategy to decrease l-carnitine content. The activity of 51 compounds was tested and we identified selective inhibitors of OCTN2. In contrast to selective inhibitors of BBOX, OCTN2 inhibitors induced a 10-fold decrease in l-carnitine content in the heart tissues and a significant 35% reduction of myocardial infarct size. In addition, OCTN2 inhibition correlated with the inhibitor content in the heart tissues, and OCTN2 could potentially be an efficient target to increase drug transport into tissues and to reduce drug elimination by urine. In conclusion, the results of this study confirm that selective inhibition of OCTN2, compared to selective inhibition of BBOX, is a far more effective approach to decrease l-carnitine content and to induce cardioprotective effects. OCTN2 could potentially be an efficient tool to increase drug transport in tissues and to reduce drug elimination via urine. PMID:24836867

  16. Relation of impaired Thrombolysis In Myocardial Infarction myocardial perfusion grades to residual thrombus following the restoration of epicardial patency in ST-elevation myocardial infarction.

    PubMed

    Kirtane, Ajay J; Weisbord, Aaron; Karmpaliotis, Dimitrios; Murphy, Sabina A; Giugliano, Robert P; Cannon, Christopher P; Antman, Elliott M; Ohman, E Magnus; Roe, Matthew T; Braunwald, Eugene; Gibson, C Michael

    2005-01-15

    Clinical and angiographic data were analyzed from 929 patients who had ST-elevation myocardial infarction and open epicardial arteries after fibrinolytic therapy. Residual angiographically evident thrombus was associated with more frequent Thrombolysis In Myocardial Infarction (TIMI) grade 2 flow (33.6% vs 26.8%, p = 0.03), higher corrected TIMI frame counts (34 vs 31 frames, p = 0.0003), and lower TIMI myocardial perfusion grades (43.0% vs 32.0% TIMI myocardial perfusion grades 0/1, p = 0.001) among all patients and among patients who had TIMI grade 3 flow (33.5% vs 26.0% TIMI myocardial perfusion grades 0/1, p = 0.043). In multivariate analyses, angiographically evident thrombus was associated with higher corrected TIMI frame counts and worsened myocardial perfusion independent of clinical and angiographic covariates, including TIMI grade 3 flow.

  17. Thrombus imaging with indium-111 and iodine-131-labeled fibrin-specific monoclonal antibody and its F(ab')2 and Fab fragments

    SciTech Connect

    Rosebrough, S.F.; Grossman, Z.D.; McAfee, J.G.; Kudryk, B.J.; Subramanian, G.; Ritter-Hrncirik, C.A.; Witanowski, L.S.; Tillapaugh-Fay, G.; Urrutia, E.; Zapf-Longo, C.

    1988-07-01

    We have previously reported successful imaging of fresh (2-4 hr old) and aged (1-5 days old) canine thrombi with /sup 131/I-labeled intact monoclonal antibody (MAb) specific for fibrin. We now report thrombus imaging with /sup 131/I-labeled F(ab')2 and Fab and /sup 111/In-labeled intact MAb, F(ab')2, and Fab. Indium-111-labeled F(ab')2 proved to be the best imaging agent due to less nonspecific binding in the liver than whole IgG. Image quality was improved by the higher administered dose permissible with /sup 111/In and its better physical characteristics for imaging, compared to /sup 131/I. Immunofluorescence of fresh human histologic sections showed intact MAb and F(ab')2 binding to thrombi, pulmonary emboli, and atherosclerotic plaques, strengthening the feasibility of clinical thrombus imaging.

  18. Endomyocardial fibrosis and mural thrombus in a 4-year-old girl due to idiopathic hypereosinophilia syndrome described with serial cardiac magnetic resonance imaging.

    PubMed

    Tai, Christiana P; Chung, Taylor; Avasarala, Kishor

    2016-01-01

    We present the case of a 4-year-old girl with idiopathic hypereosinophilia syndrome, endomyocardial fibrosis, and mural thrombus. This condition is rarely seen in children outside the tropics. Myocardial biopsy is historically the standard for diagnosis. Reports in adult literature, however, have shown the utility of cardiac MRI as a non-invasive tool for diagnosis, prognosis, and monitoring. To our knowledge, this is the first reported case with serial cardiac MRI in a child.

  19. Additional manual thrombus aspiration for ST-segment elevation myocardial infarction during percutaneous coronary intervention: an updated meta-analysis

    PubMed Central

    Zhang, Yan; Peng, Li; Fan, Yong-Yan; Lu, Cai-Yi

    2016-01-01

    Background The clinical efficacy and safety of adjunctive thrombus aspiration (TA) in patients with ST-segment elevation myocardial infarction (STEMI) during percutaneous coronary intervention (PCI) remain controversial. Methods Twenty five eligible randomized controlled trials were included to compare the use of thrombus aspiration (TA) with PCI and PCI-only for STEMI. The primary endpoint was all-cause mortality and death. The secondary endpoints were major adverse cardiac events (MACE), recurrent infarction (RI), target vessel revascularization (TVR), stent thrombosis (ST), perfusion surrogate markers and stroke. Results TIMI flow grade 3 and MBG 2–3 were significantly increased in the TA plus PCI arm compared with the PCI-only arm [relative risk (RR): 1.05, 95% confidence intervals (CI): 1.02–1.09, P = 0.004] and (RR: 1.68, 95% CI: 1.40–2.00, P < 0.001), respectively. There were no significant differences in all-cause mortality, MACEs, TVR and ST rates between the two groups. The RI rate was lower in the TA plus PCI arm than that in the PCI-only arm with short-term follow-up duration (RR: 0.60, 95% CI: 0.38–0.96, P = 0.03), but there was no significant difference in RI incidence over the medium- or long-term follow-up periods (RR: 1.00, 95% CI: 0.77–1.29, P = 0.98), and (RR: 0.96, 95% CI: 0.81–1.15, P = 0.69), respectively. There were statistically significant differences in the rates of crude stroke and stroke over the medium- or long-term follow-up periods and the crude stroke rate in the TA plus PCI (RR: 1.60, 95% CI: 1.08–2.38, P = 0.02) and (RR: 1.43, 95% CI: 1.03–1.98, P = 0.03), respectively; this was not observed between the two arms during the short-term follow-up period (RR: 1.47, 95% CI: 0.97–2.21, P = 0.07). Conclusions Routine TA-assisted PCI in STEMI patients can improve myocardial reperfusion and get limited benefits related to the clinical endpoints, which may be associated with stroke risk. PMID:27403144

  20. The pyrrolidinoindoline alkaloid Psm2 inhibits platelet aggregation and thrombus formation by affecting PI3K/Akt signaling

    PubMed Central

    Su, Xing-li; Su, Wen; Wang, Ying; Wang, Yue-hu; Ming, Xin; Kong, Yi

    2016-01-01

    Aim: Psm2, one of the pyrrolidinoindoline alkaloids isolated from whole Selaginella moellendorffii plants, has shown a potent antiplatelet activity. In this study, we further evaluated the antiplatelet effects of Psm2, and elucidated the underlying mechanisms. Methods: Human platelet aggregation in vitro and rat platelet aggregation ex vivo were investigated. Agonist-induced platelet aggregation was measured using a light transmission aggregometer. The antithrombotic effects of Psm2 were evaluated in arteriovenous shunt thrombosis model in rats. To elucidate the mechanisms underlying the antiplatelet activity of Psm2, ELISAs, Western blotting and molecular docking were performed. The bleeding risk of Psm2 administration was assessed in a mouse tail cutting model, and the cytotoxicity of Psm2 was measured with MTT assay in EA.hy926 cells. Results: Psm2 dose-dependently inhibited human platelet aggregation induced by ADP, U4619, thrombin and collagen with IC50 values of 0.64, 0.37, 0.35 and 0.87 mg/mL, respectively. Psm2 (1, 3, 10 mg/kg) administered to rats significantly inhibited platelet aggregation ex vivo induced by ADP. Psm2 (1, 3, 10 mg/mL, iv) administered to rats with the A–V shunt dose-dependently decreased the thrombus formation. Psm2 inhibited platelet adhesion to fibrinogen and collagen with IC50 values of 84.5 and 96.5 mg/mL, respectively, but did not affect the binding of fibrinogen to GPIIb/IIIa. Furthermore, Psm2 inhibited AktSer473 phosphorylation, but did not affect MAPK signaling and Src kinase activation. Molecular docking showed that Psm2 bound to phosphatidylinositol 3-kinase β (PI3Kβ) with a binding free energy of −13.265 kcal/mol. In addition, Psm2 did not cause toxicity in EA.hy926 cells and produced only slight bleeding in a mouse tail cutting model. Conclusion: Psm2 inhibits platelet aggregation and thrombus formation by affecting PI3K/Akt signaling. Psm2 may be a lead compound or drug candidate that could be developed for the

  1. Effect of low dose acetylsalicylic acid on the frequency and hematologic activity of left ventricular thrombus in anterior wall acute myocardial infarction

    SciTech Connect

    Kuepper, A.J.V.; Verheugt, F.W.; Peels, C.H.; Galema, T.W.; den Hollander, W.; Roos, J.P.

    1989-04-15

    In this prospective, randomized, placebo-controlled trial the effect of 100 mg acetylsalicylic acid (ASA) once daily on the incidence, hematologic activity and embolic potential of left ventricular (LV) thrombosis was studied in 100 consecutive patients with a first anterior wall acute myocardial infarction (AMI). Patients were randomized to ASA or placebo less than 12 hours after onset of symptoms. Heparin, 5,000 IU subcutaneously twice daily, was given to all patients during immobilization. Echocardiography was performed less than 24 hours, 48 to 72 hours and 1, 2, and 12 weeks after AMI. LV thrombosis was detected by echocardiography in 30 (33%) of the 92 evaluable patients (15 patients given ASA and 15 given placebo). Indium-111 platelet scintigraphy was done in 17 of the 22 patients with an LV thrombus at the second week echocardiogram. Among 7 ASA-treated patients, 4 had positive images; among 10 placebo patients, 5 had positive images. LV thrombus resolution was noted in 3 of 9 patients with a positive scan and in 5 of 8 patients with a negative platelet scan. In 7 of 10 ASA-treated patients and 5 of 12 placebo-treated patients thrombus resolution was observed (difference not significant). Systemic embolism occurred in 2 patients, both given ASA, during the first week after AMI. Thus, low dose ASA has no effect on the incidence, hematologic activity and embolic potential of LV thrombosis in anterior wall AMI.

  2. Size Matters

    ERIC Educational Resources Information Center

    Gehring, John

    2004-01-01

    This article describes the immense size of Unity Junior High School in Cicero, Illinois and the opinions of various people regarding its size. The school has more than 2,700 students, seventeen acres, eighty-eight faculty lounges, and ninety-six security cameras. Administrators hope the school--"Cicero's crown jewel," as the school district's Web…

  3. Using Daily Plasma-Free Hemoglobin Levels for Diagnosis of Critical Pump Thrombus in Patients Undergoing ECMO or VAD Support

    PubMed Central

    Neal, James R.; Quintana, Eduard; Pike, Roxann B.; Hoyer, James D.; Joyce, Lyle D.; Schears, Gregory

    2015-01-01

    Abstract: Patients supported with extracorporeal membrane oxygenation (ECMO) or short-term centrifugal ventricular assist devices (VADs) are at risk for potential elevation of plasma-free hemoglobin (pfHb) during treatment. The use of pfHb testing allows detection of subclinical events with avoidance of propagating injury. Among 146 patients undergoing ECMO and VAD from 2009 to 2014, five patients experienced rapid increases in pfHb levels over 100 mg/dL. These patients were supported with CardioHelp, Centrimag, or Pedimag centrifugal pumps. Revolutions per minute of the pump head and flow in the circuit in three of the patients did not change, to maintain patient flow during the period that pfHb level spiked. Two patients had unusual vibrations originating from the pump head during the pfHb spike. Four patients had pump head replacement. Following intervention, trending pfHb levels demonstrated a rapid decline over the next 12 hours, returning to baseline within 48 hours. Two of the three patients who survived to discharge also experienced acute kidney injury, which was attributed to pfHb elevations. The kidney injury resolved over time. The architecture of centrifugal pumps may have indirectly contributed to red blood cell damage due to thrombus, originally from the venous line or venous cannula, being snared in the pump fins or pump head. PMID:26405358

  4. An Integrated Fluid-Chemical Model Toward Modeling the Formation of Intra-Luminal Thrombus in Abdominal Aortic Aneurysms

    PubMed Central

    Biasetti, Jacopo; Spazzini, Pier Giorgio; Swedenborg, Jesper; Gasser, T. Christian

    2012-01-01

    Abdominal Aortic Aneurysms (AAAs) are frequently characterized by the presence of an Intra-Luminal Thrombus (ILT) known to influence their evolution biochemically and biomechanically. The ILT progression mechanism is still unclear and little is known regarding the impact of the chemical species transported by blood flow on this mechanism. Chemical agonists and antagonists of platelets activation, aggregation, and adhesion and the proteins involved in the coagulation cascade (CC) may play an important role in ILT development. Starting from this assumption, the evolution of chemical species involved in the CC, their relation to coherent vortical structures (VSs) and their possible effect on ILT evolution have been studied. To this end a fluid-chemical model that simulates the CC through a series of convection-diffusion-reaction (CDR) equations has been developed. The model involves plasma-phase and surface-bound enzymes and zymogens, and includes both plasma-phase and membrane-phase reactions. Blood is modeled as a non-Newtonian incompressible fluid. VSs convect thrombin in the domain and lead to the high concentration observed in the distal portion of the AAA. This finding is in line with the clinical observations showing that the thickest ILT is usually seen in the distal AAA region. The proposed model, due to its ability to couple the fluid and chemical domains, provides an integrated mechanochemical picture that potentially could help unveil mechanisms of ILT formation and development. PMID:22934022

  5. Effect of troxerutin on laser-induced thrombus formation in rat mesenteric vessels, coagulation parameters and platelet function.

    PubMed

    Krupiński, K; Giedrojć, J; Bielawiec, M

    1996-01-01

    The antithrombotic effect of Troxerutin have been studied in an experimental model of thrombosis in which rat mesenteric vessels (arterioles and venules) 25-30 microns in diameter were injured by well defined argon laser lesions. Furthermore in vitro effect of this agent on coagulation parameters (IIa, Xa inhibition, TT, heptest), and platelet function (platelet adhesion to the siliconised glass and extracellular matrix, platelet spreading) has been investigated 2 h after oral drug administration. Troxerutin at a dose of 10 mg/kg markedly inhibited thrombus formation in venules. Higher dose (50 mg/kg) was needed to obtain the same antithrombotic effect when arterioles were studied. After application of a single dose of Troxerutin (100 mg/kg) antithrombotic effect lasted for 6 h to 7.5 h when venules were studied, and for 4.5 h to 6 h when arterioles were investigated. In in vitro study we did not observe any effect of Troxerutin on coagulation parameters. In concentrations of 100 micrograms/ml in platelet rich plasma Troxerutin significantly inhibited platelet adhesion to the extracellular matrix and siliconised glass as well as platelet spreading. It is likely that this drug possesses antithrombotic effect evaluated by inhibition of platelet function and protection of endothelial cells.

  6. Quick photo-Fenton degradation of phenolic compounds by Cu/Al2O3-MCM-41 under visible light irradiation: small particle size, stabilization of copper, easy reducibility of Cu and visible light active material.

    PubMed

    Pradhan, Amaresh C; Nanda, Binita; Parida, K M; Das, Mira

    2013-01-14

    The present study reports the photo-Fenton degradation of phenolic compounds (phenol, 2-chloro-4-nitrophenol and 4-chloro-2-nitrophenol) in aqueous solution using mesoporous Cu/Al(2)O(3)-MCM-41 nanocomposite as a heterogeneous photo-Fenton-like catalyst. The in situ incorporation of mesoporous Al(2)O(3) (MA) into the framework of MCM-41 (sol-gel method) forms Al(2)O(3)-MCM-41 and wetness impregnation of Cu(II) on Al(2)O(3)-MCM-41 generates mesoporous Cu/Al(2)O(3)-MCM-41 composite. The effects of pH and H(2)O(2) concentration on degradation of phenol, 2-chloro-4-nitrophenol and 4-chloro-2-nitrophenol are studied. Kinetics analysis shows that the photocatalytic degradation reaction follows a first-order rate equation. Mesoporous 5 Cu/Al(2)O(3)-MCM-41 is found to be an efficient photo-Fenton-like catalyst for the degradation of phenolic compounds. It shows nearly 100% degradation in 45 min at pH 4. The combined effect of small particle size, stabilization of Cu(2+) on the support Al(2)O(3)-MCM-41, ease reducibility of Cu(2+) and visible light activeness are the key factors for quick degradation of phenolic compounds by Cu/Al(2)O(3)-MCM-41. PMID:23090390

  7. Acetic acid in aged vinegar affects molecular targets for thrombus disease management.

    PubMed

    Jing, Li; Yanyan, Zhang; Junfeng, Fan

    2015-08-01

    To elucidate the mechanism underlying the action of dietary vinegar on antithrombotic activity, acetic acid, the main acidic component of dietary vinegar, was used to determine antiplatelet and fibrinolytic activity. The results revealed that acetic acid significantly inhibits adenosine diphosphate (ADP)-, collagen-, thrombin-, and arachidonic acid (AA)-induced platelet aggregation. Acetic acid (2.00 mM) reduced AA-induced platelet aggregation to approximately 36.82 ± 1.31%, and vinegar (0.12 mL L(-1)) reduced the platelet aggregation induced by AA to 30.25 ± 1.34%. Further studies revealed that acetic acid exerts its effects by inhibiting cyclooxygenase-1 and the formation of thromboxane-A2. Organic acids including acetic acid, formic acid, lactic acid, citric acid, and malic acid also showed fibrinolytic activity; specifically, the fibrinolytic activity of acetic acid amounted to 1.866 IU urokinase per mL. Acetic acid exerted its fibrinolytic activity by activating plasminogen during fibrin crossing, thus leading to crosslinked fibrin degradation by the activated plasmin. These results suggest that organic acids in dietary vinegar play important roles in the prevention and cure of cardiovascular diseases.

  8. Hinokitiol inhibits platelet activation ex vivo and thrombus formation in vivo.

    PubMed

    Lin, Kuan H; Kuo, Jinn R; Lu, Wan J; Chung, Chi L; Chou, Duen S; Huang, Shih Y; Lee, Hsiu C; Sheu, Joen R

    2013-05-15

    Hinokitiol is a tropolone-related bioactive compound that has been used in hair tonics, cosmetics, and food as an antimicrobial agent. Recently, hinokitiol has attracted considerable interest because of its anticancer activities. Platelet activation plays a crucial role in atherothrombotic processes. We examined the effects of hinokitiol treatment on platelet activation using human platelets. In the present study, hinokitiol (1 and 2 μM) inhibited the collagen-induced aggregation of human platelets, but did not inhibit the activation of platelets by other agonists, including thrombin, arachidonic acid, and ADP. Hinokitiol inhibited the phosphorylation of phospholipase C (PLC)γ2, protein kinase C (PKC), mitogen-activated protein kinases (MAPKs), and Akt in collagen-activated human platelets, and significantly reduced intracellular calcium mobilization and hydroxyl radical (OH·) formation. Hinokitiol also reduced the PKC activation and platelet aggregation stimulated by PDBu. In addition, hinokitiol significantly prolonged thrombogenesis in mice. Hinokitiol did not influence the binding of a fluorescent triflavin probe to the αIIbβ3 integrin on platelet membrane, and neither ODQ nor SQ22536 significantly reversed the hinokitiol-mediated inhibition of platelet aggregation. In conclusion, hinokitiol may inhibit platelet activation by inhibiting the PLCγ2-PKC cascade and hydroxyl radical formation, followed by suppressing the activation of MAPKs and Akt. Our study suggests that hinokitiol may represent a potential therapeutic agent for the prevention or treatment of thromboembolic disorders. PMID:23473801

  9. Does size matter?

    SciTech Connect

    Carreras, B. A.; Newman, D. E.; Dobson, Ian

    2014-06-15

    Failures of the complex infrastructures society depends on having enormous human and economic cost that poses the question: Are there ways to optimize these systems to reduce the risks of failure? A dynamic model of one such system, the power transmission grid, is used to investigate the risk from failure as a function of the system size. It is found that there appears to be optimal sizes for such networks where the risk of failure is balanced by the benefit given by the size.

  10. A high-fat diet containing whole walnuts (Juglans regia) reduces tumour size and growth along with plasma insulin-like growth factor 1 in the transgenic adenocarcinoma of the mouse prostate model.

    PubMed

    Davis, Paul A; Vasu, Vihas T; Gohil, Kishorchandra; Kim, Hyunsook; Khan, Imran H; Cross, Carroll E; Yokoyama, Wallace

    2012-11-28

    Prostate cancer (PCa) has been linked to fat intake, but the effects of both different dietary fat levels and types remain inconsistent and incompletely characterised. The effects on PCa in the transgenic adenocarcinoma of the mouse prostate (TRAMP) cancer model of an elevated fat (20 % of energy as fat) diet containing 155 g of whole walnuts were compared to those of an elevated fat (20 % of energy as soyabean oil) diet with matched macronutrients, tocopherols as well as a low-fat (8 % of energy as soyabean oil) diet. Mice, starting at 8 weeks of age, consumed one of the three different diets ad libitum; and prostates, livers and blood were obtained after 9, 18 or 24 weeks of feeding. No differences were observed in whole animal growth rates in either high-fat (HF) diet group, but prostate tumour weight and growth rate were reduced in the walnut diet group. Walnut diet group prostate weight, plasma insulin-like growth factor 1, resistin and LDL were lower at 18 weeks, while no statistically significant prostate weight differences by diet were seen at 9 or 24 weeks. Multiple metabolites in the livers differed by diet at 9 and 18 weeks. The walnut diet's beneficial effects probably represent the effects of whole walnuts' multiple constituents and not via a specific fatty acid or tocopherols. Moreover, as the two HF diets had dissimilar effects on prostate tumour growth rate and size, and yet had the same total fat and tocopherol composition and content, this suggests that these are not strongly linked to PCa growth.

  11. The efficacy and safety of postoperative adjuvant transarterial embolization and radiotherapy in hepatocellular carcinoma patients with portal vein tumor thrombus

    PubMed Central

    Bai, Tao; Chen, Jie; Xie, Zhi-Bo; Wu, Fei-Xiang; Wang, Si-Da; Liu, Jun-Jie; Li, Le-Qun

    2016-01-01

    Objective This study aims to find out the safety and efficiency of postoperative adjuvant transarterial chemoembolization (TACE) and radiotherapy (RT) in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT). Methods From 2009 to 2010, a total of 92 HCC patients with PVTT were enrolled in this retrospective study. Patients were divided into three groups according to their adjuvant therapies (conservative group, n=51; TACE group, n=31; RT group, n=10). Results In our analysis, median survival in patients with postoperative adjuvant TACE (21.91±3.60 months) or RT (14.53±1.61 months) was significantly longer than patients with hepatectomy alone (8.99±1.03 months). But the difference between adjuvant TACE and RT was of no significance (P=0.716). Also a similar result could be observed in median disease-free survival: conservative group (6.51±1.44 months), TACE group (13.98±3.38 months), and RT group (14.03±2.40 months). Treatment strategies (hazard ratio [HR] =0.411, P<0.001) and PVTT type (HR =4.636, P<0.001) were the independent prognostic factors for overall survival. Similarly, the risk factors were the same when multivariate analysis was conducted in disease-free survival (treatment strategies, HR =0.423, P<0.001; PVTT type, HR =4.351, P<0.001) and recurrence (treatment strategies, HR =0.459, P=0.030; PVTT type, HR =2.908, P=0.047). Patients with PVTT type I had longer overall survival than patients with PVTT type II (median survival: 18.43±2.88 months vs 11.59±1.45 months, P=0.035). Conclusion Postoperative adjuvant TACE and RT may be a choice for HCC patients with PVTT. PMID:27390524

  12. Thrombus imaging: A comparison of radiolabeled GC4 and T2G1s fibrin-specific monoclonal antibodies

    SciTech Connect

    Rosebrough, S.F.; McAfee, J.G.; Grossman, Z.D.; Kudryk, B.J.; Ritter-Hrncirik, C.A.; Witanowski, L.S.; Maley, B.L.; Bertrand, E.A.; Gagne, G.M. )

    1990-06-01

    Radioimmunoimaging of experimentally-induced canine thrombi has previously been achieved with iodine-131- and indium-111-labeled ({sup 131}I and {sup 111}In) anti-fibrin T2G1s monoclonal antibody (MAb). We now compare T2G1s to another anti-fibrin MAb, designated GC4, for imaging fresh and aged canine thrombi. GC4 is specific for a neoepitope exposed on fibrin later in the thrombolytic process after plasmin digestion. Femoral venous thrombi were induced in six groups of dogs, each containing three dogs. In two groups, the MAbs were compared when the thrombi were 3-hr or 3-days old at the time of injection, and the dogs were killed at 48 hr. In thrombi 3-hr-old, the GC4/T2G1s concentration ratio averaged 0.53 compared to 1.9 in 3-day-old thrombi. Two groups of dogs with thrombi 1- or 3-days-old were heparinized before MAb injection and were killed at 24 hr. The heparinized dogs with thrombi 1- or 3-days-old had GC4/T2G1s mean ratios of 2.3 and 2.9, respectively. In the unheparinized groups, the corresponding ratios were 1.1 and 1.9. GC4 may be more useful for clinical thrombus imaging than T2G1s because spontaneous venous thrombi are usually several days old at the time of presentation and patients are often heparinized immediately.

  13. Clinical predictors and outcomes of patients with left ventricular thrombus following ST-segment elevation myocardial infarction.

    PubMed

    Garber, Adam M; Mentz, Robert J; Al-Khalidi, Hussein R; Shaw, Linda K; Fiuzat, Mona; O'Connor, Christopher M; Velazquez, Eric J

    2016-04-01

    We aimed to characterize the independent predictors of LVT following STEMI and the association with outcomes. The clinical predictors of left ventricular thrombus (LVT) formation after ST-segment elevation myocardial infarction (STEMI) are not well-defined in the contemporary era. We performed a retrospective analysis of STEMI patients at Duke from 2000 to 2011 who had a transthoracic echocardiogram within 90 days post-STEMI and compared patients with and without LVT (LVT+ vs. LVT-). Univariate Cox proportional hazards regression models of baseline characteristics were examined and significant variables were used in a multivariable model to assess adjusted relationships with LVT. A multivariable Cox PH survival model with covariate adjustments was used for assessment of LVT and long-term mortality. Of all eligible patients, 1734 patients met inclusion criteria and 4.3 % (N = 74) had a LVT. LVT+ patients tended to have a history of heart failure (HF) and higher initial troponin compared to LVT- patients. After adjustment, higher heart rate, non-white race, HF severity, and presence of left anterior descending artery (LAD) disease were independent predictors of LVT. There was a trend toward an association between LVT and increased all-cause mortality (HR 1.36; 95 % CI 0.84-2.21, P = 0.22), however this was not statistically significant. LVT was seen in over 4 % of this contemporary post-STEMI population. Several baseline characteristics were independently associated with LVT: Heart rate, HF severity, LAD disease, and non-white race. Prospective studies are warranted to determine whether anticoagulation in patients at increased risk for LVT improves outcomes.

  14. Discrimination between platelet-mediated and coagulation-mediated mechanisms in a model of complex thrombus formation i