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Sample records for blood platelet disorders

  1. Platelet Disorders

    Science.gov (United States)

    ... higher risk of blood clots. With other platelet disorders, the platelets do not work as they should. ... This can cause excessive bleeding. Treatment of platelet disorders depends on the cause. NIH: National Heart, Lung, ...

  2. The change and significance of platelet parameters and blood coagulation function index in patients with hypertensive disorder complicating pregnancy

    Institute of Scientific and Technical Information of China (English)

    Yu-Xia Shi; Yi-Xin Yang; Qian Xu; Yanhua Zhu

    2015-01-01

    Objective:To explore the change and significance of platelet parameters and blood coagulation function index in patients with hypertensive disorder complicating pregnancy.Methods: Chose 89 patients with HDCP, they were set as HDCP group, chose another 60 cases health late pregnancy women and 42 cases non pregnant female, they were set as late pregnant group and non-pregnant control group, detected the platelet parameters: the average blood platelet count (PLT), platelet volume (MPV), platelet distribution width (PDW) and blood coagulation indexes, plasma prothrombin time (PT), thrombin time (TT), fibrinogen (FIB), D-dimer (D-D), activated partial blood coagulation time (APTT) live enzymes in three groups.Results: (1) Compared with the non-pregnant group and late pregnant group, PLT was significantly lower, while the MPV and PDW were significantly higher in HDCP group; PLT in late pregnant group was significantly lower than that in non-pregnant group, and there were no significantly difference of MPV and PDW in the two groups; (2) Compared with the non-pregnant group and late pregnant group, PT and APTT levels were significantly lower, while FIB and D-D were significantly higher in HDCP group; The level of PT and APTT in late pregnant group were significantly lower, and FIB and D-D levels were significantly higher than that in non-pregnant group, However, The level of TT were no statistical significance difference among the three groups.Conclusion: HDCP existence phenomenon of platelet activation and apparent high coagulation state, dynamic detection of HDCP patients platelet parameters and blood coagulation indexes to prevent related complications, improve obstetrics safety is of great significance.

  3. Platelet Function Tests in Bleeding Disorders.

    Science.gov (United States)

    Lassila, Riitta

    2016-04-01

    Functional disorders of platelets can involve any aspect of platelet physiology, with many different effects or outcomes. These include platelet numbers (thrombocytosis or thrombocytopenia); changes in platelet production or destruction, or capture to the liver (Ashwell receptor); altered adhesion to vascular injury sites and/or influence on hemostasis and wound healing; and altered activation or receptor functions, shape change, spreading and release reactions, procoagulant and antifibrinolytic activity. Procoagulant membrane alterations, and generation of thrombin and fibrin, also affect platelet aggregation. The above parameters can all be studied, but standardization and quality control of assay methods have been limited despite several efforts. Only after a comprehensive clinical bleeding assessment, including family history, information on drug use affecting platelets, and exclusion of coagulation factor, and tissue deficits, should platelet function testing be undertaken to confirm an abnormality. Current diagnostic tools include blood cell counts, platelet characteristics according to the cell counter parameters, peripheral blood smear, exclusion of pseudothrombocytopenia, whole blood aggregometry (WBA) or light transmission aggregometry (LTA) in platelet-rich plasma, luminescence, platelet function analysis (PFA-100) for platelet adhesion and deposition to collagen cartridges under blood flow, and finally transmission electron microscopy to exclude rare structural defects leading to functional deficits. The most validated test panels are included in WBA, LTA, and PFA. Because platelets are isolated from their natural environment, many simplifications occur, as circulating blood and interaction with vascular wall are omitted in these assays. The target to reach a highly specific platelet disorder diagnosis in routine clinical management can be exhaustive, unless needed for genetic counseling. The elective overall assessment of platelet function disorder

  4. Genomics of platelet disorders.

    Science.gov (United States)

    Westbury, S K; Mumford, A D

    2016-07-01

    Genetic diagnosis in families with inherited platelet disorders (IPD) is not performed widely because of the genetic heterogeneity of this group of disorders and because in most cases, it is not possible to select single candidate genes for analysis using clinical and laboratory phenotypes. Next-generation sequencing (NGS) technology has revolutionized the scale and cost-effectiveness of genetic testing, and has emerged as a valuable tool for IPD. This review examines the potential utility of NGS as a diagnostic tool to streamline detection of causal variants in known IPD genes and as a vehicle for new gene discovery. PMID:27405671

  5. Preliminary studies of a platelet function disorder in Simmental cattle.

    OpenAIRE

    Searcy, G. P.; Sheridan, D; Dobson, K A

    1990-01-01

    A bleeding disorder due to abnormal platelet function occurs in Simmental cattle. Whole blood from these animals underwent good clot retraction. Platelet aggregation in response to adenosine diphosphate (ADP) and collagen in a whole blood aggregation system was markedly impaired. Normal bovine platelets in a whole blood aggregation system showed very little aggregation in response to epinephrine and arachidonic acid. Aggregation in platelet-rich plasma was negligible in response to ADP, colla...

  6. Extending The Shelf Life Of Blood Platelets

    Science.gov (United States)

    Surgenor, Douglas M.

    1988-01-01

    New method of storing human blood platelets extends vitality for transfusions. Packaged as suspension in sterile liquid in plastic blood bags. Each bag placed between pair of plastic grids, and rubberbands placed around sandwich thus formed to hold together. Stored upright in open air or in container through which air pumped at rate of at least 45 L/min. Ensures that platelets receive ample oxygen and expiratory carbon dioxide form platelets removed before pH drops to harmful levels.

  7. Chapter 19. Blood and bone marrow. C. Blood platelet kinetics

    International Nuclear Information System (INIS)

    The blood platelet life span was measured by labelling the circulating population in vivo and in vitro. DF32P labelling in vivo: DFP is a specific inhibitor of acetyl-cholinesterase and hence in vivo labels blood platelets in the same way as the red cells and white cells which contain this enzyme. Sodium chromate 51Cr: this is the method used almost universally and the various stages were described. Several parameters were studied: the percentage of blood platelets in circulation, the aspect of the radioactivity decay curve, blood platelet production. Results obtained by the use of a medulla tracer, 75Se selenomethionine, were also reported. Finally the practical use of the blood platelet kinetics measurements were demonstrated

  8. Does bipolar pacemaker current activate blood platelets?

    DEFF Research Database (Denmark)

    Gjesdal, Grunde; Hansen, Annebirthe Bo; Brandes, Axel

    2009-01-01

    platelets and muscle cells contain actin and myosin filaments, and both cells are activated following calcium influx. Muscle cells open their calcium channels and contract when exposed to an electric current. Current through a bipolar pacemaker lead will expose a small volume of blood, including platelets......, to the depolarizing current. Platelet activation may ensue, resulting in aggregation, release reaction, and contraction. In contrast, a unipolar pacemaker system will not depolarize blood, but transmit current directly into the myocardium, and the current afterward passes through other tissues before...

  9. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Susan Skanderup Falkenberg

    2012-01-01

    Full Text Available 12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM and collagen- (2.0 μg/mL induced aggregations in human blood. These four species in respective extracts (in brackets were Blechnum chilense (MeOH, Luma apiculata (H2O, Amomyrtus luma (DCM : MeOH 1 : 1 and Cestrum parqui (DCM : MeOH 1 : 1. The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1, and L. apiculata (H2O were substantial and confirmed by inhibition of platelet surface activation markers.

  10. Platelet aggregation and quality control of platelet concentrates produced in the Amazon Blood Bank

    OpenAIRE

    Maria José Dantas Coêlho; Taysa de Castro Monteiro; Felicien Gonçalves Vasquez; Kátia Luz Torres Silva; Kleber Sandro Brasil dos Santos; Viviana Maria Araújo de Oliveira; Francimary de Oliveira Cavalcante

    2011-01-01

    BACKGROUND: The study of platelet aggregation is essential to assess in vitro platelet function by different platelet activation pathways. OBJECTIVE: To assess aggregation and biochemical parameters of random platelet concentrates produced at the Fundação HEMOAM using the quality control tests defined by law. METHODS: Whole blood samples from 80 donors and the respective platelet concentrate units were tested. Platelet concentrates were tested (platelet count, aggregation and pH) on days 1, 3...

  11. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    OpenAIRE

    Susan Skanderup Falkenberg; Inge Tarnow; Alfonso Guzman; Per Mølgaard; Henrik Toft Simonsen

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H2O), Amomyrtus l...

  12. Lea blood group antigen on human platelets

    International Nuclear Information System (INIS)

    One- and two-stage radioligand assays were used to determine if human platelets possess the Lea antigen. Goat IgG anti-Lea antibody was purified by multiple adsorptions with Le(a-b-) human red blood cells, followed by affinity chromatography with synthetic Lea substance and labeling with 125I. Human IgG anti-Lea antibody was used either in a two stage radioassay with 125I-labeled mouse monoclonal IgG anti-human IgG as the second antibody or, alternatively, purified by Staph protein A chromatography, labeled with 125I, and used in a one-stage radioassay. Platelets from donors of appropriate red blood cell phenotypes were incubated with the antisera, centrifuged through phthalate esters, and assayed in a gamma scintillation counter. Dose response and saturation curve analysis demonstrate the presence of Lewis a antigen on platelets from Lea+ donors. Furthermore, platelets from an Le(a-b-) donor incubated in Le (a+b-) plasma adsorb Lea antigen in a similar manner to red blood cells. The clinical significance of these antigens in platelet transfusion remains undefined

  13. Inherited Platelet Function Disorders: Algorithms for Phenotypic and Genetic Investigation.

    Science.gov (United States)

    Gresele, Paolo; Bury, Loredana; Falcinelli, Emanuela

    2016-04-01

    Inherited platelet function disorders (IPFDs) manifest with mucocutaneous bleeding and are frequently difficult to diagnose due to their heterogeneity, the complexity of the platelet activation pathways and a lack of standardization of the platelet function laboratory assays and of their use for this purpose. A rational diagnostic approach to IPFDs should follow an algorithm where clinical examination and a stepwise laboratory evaluation play a crucial role. A streamlined panel of laboratory tests, with consecutive steps of increasing level of complexity, allows the phenotypic characterization of most IPFDs. A first-line diagnosis of a significant fraction of the IPFD may be made also at nonspecialized centers by using relatively simple tests, including platelet count, peripheral blood smear, light transmission aggregometry, measurement of platelet granule content and release, and the expression of glycoproteins by flow cytometry. Some of the most complex, second- and third-step tests may be performed only in highly specialized laboratories. Genotyping, including the widespread application of next-generation sequencing, has enabled discovery in the last few years of several novel genes associated with platelet disorders and this method may eventually become a first-line diagnostic approach; however, a preliminary clinical and laboratory phenotypic characterization nowadays still remains crucial for diagnosis of IPFDs. PMID:26962877

  14. Symptoms of Blood Disorders

    Science.gov (United States)

    ... 2 Diabetes, Heart Disease a Dangerous Combo Are 'Workaholics' Prone to OCD, Anxiety? ALL NEWS > Resources First ... Blood Disorders Bone Marrow Examination Blood disorders can cause various symptoms in almost any area of the ...

  15. Decreased mean platelet volume in panic disorder

    Directory of Open Access Journals (Sweden)

    Göğçegöz Gül I

    2014-09-01

    Full Text Available Işil Göğçegöz Gül, Gül Eryilmaz, Eylem Özten, Gökben Hizli Sayar Neuropsychiatry Health, Practice, and Research Center, Uskudar University, Istanbul, Turkey Aim: The relationship between psychological stress and platelet activation has been widely studied. It is well known that platelets may reflect certain biochemical changes that occur in the brain when different mental conditions occur. Platelet 5-hydroxytryptamine (5-HT is also extensively studied in psychiatry. The mean platelet volume (MPV, the accurate measure of platelet size, has been considered a marker and determinant of platelet function. The aim of the present study was to search for any probable difference in the MPV of subjects with panic disorder (PD.Methods: A total of 37 drug-free subjects, aged 18 to 65 years, diagnosed with PD, with or without agoraphobia, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth edition (DSM-IV criteria and 45 healthy control subjects were included in the study. Platelet count and MPV were measured and recorded for each subject.Results: There were no statistically significant differences between groups in terms of female/male ratio, age, or body mass index between the PD group and control group (P=0.91, P=0.82, and P=0.93, respectively. The MPV was found to be significantly lower in the PD group compared with the control group (8.8±0.9 fL vs 9.2±0.8 fL; P=0.02. All the participants had MPV values in the standard range of 6.9–10.8 fL.Conclusion: We concluded that abnormalities of the 5-HT1A receptor function in the central nervous system of subjects with a diagnosis of PD are also mirrored in as an alteration in platelet activity. Measurements of platelet activity may be used as a tool for neuropsychiatric and psychopharmacological research and for studying how certain mental diseases and medications affect the central nervous system. Keywords: 5-HT, thrombocyte, anxiety 

  16. Alterations in aggregation function of whole blood platelets following irradiation

    International Nuclear Information System (INIS)

    By using whole blood platelet aggregometer, changes of platelet aggregation function following γ-irradiation with 6 Gy were studied. The results indicated that the function of platelet aggreation was enhanced from 4 hour to the third day after radiation, the peak value being on the third day. But it reduced on the seventh and tenth days. The early elevation of platelet aggregation may aggravate the microcirculation disturbances, while the reduction of platelet aggregation is one of the causes of hemorrhage syndrome following radiation. Therefore, measures effective in early inhibition and late improvement of platelet aggregation function may be helpful in repair of acute radiation injury

  17. Topographic Cues Reveal Two Distinct Spreading Mechanisms in Blood Platelets

    OpenAIRE

    Rabea Sandmann; Sarah Köster

    2016-01-01

    Blood platelets are instrumental in blood clotting and are thus heavily involved in early wound closure. After adhering to a substrate they spread by forming protrusions like lamellipodia and filopodia. However, the interaction of these protrusions with the physical environment of platelets while spreading is not fully understood. Here we dynamically image platelets during this spreading process and compare their behavior on smooth and on structured substrates. In particular we analyze the te...

  18. Radiolabeled platelets

    International Nuclear Information System (INIS)

    Initial interest in developing techniques to radiolabel platelets was spurred by the lack of an accurate method for measuring platelet life span in both normals and in thrombocytopenic patients. Early investigators could obtain only rough estimates of platelet life spans by monitoring the platelet counts of thrombocytopenic patients undergoing platelet transfusions. Labels were also sought that would allow imaging of platelets in vivo in order to better understand the pathophysiology of atherosclerosis, thrombophlebitis, and clotting disorders, and to improve the clinical diagnosis of these diseases. Two types of platelet labels were investigated: cohort (pulse) labels and random labels. Cohort labels are taken up by megakaryocytes in the bone marrow and incorporated in the DNA and other components of the forming platelet. In theory, only freshly released platelets of a uniform age are labeled. Random labels, on the other hand, tag platelets in the peripheral blood, labeling platelets of all ages

  19. Pseudo grey platelet syndrome--grey platelets due to degranulation in blood collected into EDTA.

    Science.gov (United States)

    Cockbill, S R; Burmester, H B; Heptinstall, S

    1988-10-01

    We have studied a woman with a history of mild bruising and bleeding, with a normal platelet count and normal clotting factors, who had platelets that appeared grey when stained and viewed under the microscope. Unlike the grey platelet syndrome, the abnormality was only evident when blood had been collected into EDTA and not when citrate or heparin was used as anticoagulant. This 'pseudo grey platelet syndrome' was associated with platelet dense body and alpha granule secretion with no aggregation and occurred on removal of extracellular Ca2+. We discovered that a plasma factor was responsible which could be an immunoglobulin but which is clearly different from the EDTA-sensitive antibodies which cause platelet aggregation and agglutination. We were not able to demonstrate a relationship between the mild bleeding tendency and the in vitro abnormality. PMID:3143601

  20. A computer planning model for blood platelet production and distribution.

    Science.gov (United States)

    Sirelson, V; Brodheim, E

    1991-08-01

    We consider a class of policies for stocking hospital blood banks with units of random donor platelet concentrate ('Platelets') based upon scheduled daily deliveries from a regional blood center to replenish the platelet inventory to a fixed 'base stock' level. The measures of interest are the 'shortage rate' (the proportion of days for which the on-hand inventory at the hospital blood bank is insufficient to meet the demand) and the 'outdate rate' (the proportion of total units shipped which are not transfused within the usable life span of 5 days). Our principal results give a predictive model which relates the base stock level to the shortage rate and outdate rate. Our model uses only the mean daily demand as a parameter. It provides a basis to unify the results from other studies which have demonstrated improvements in platelet inventory management in particular hospitals and blood centers. PMID:1752123

  1. Current and emerging approaches for evaluating platelet disorders.

    Science.gov (United States)

    Podda, G; Femia, E A; Cattaneo, M

    2016-05-01

    Platelets play a central role in physiological hemostasis and also in pathological thrombosis. It is well established that congenital or acquired abnormalities of platelet function are associated with a heightened risk of bleeding of variable severity and excessive hemorrhage after surgery or trauma. Several kinds of different platelet function tests have been developed over the years to identify or diagnose platelet function disorders. The use of these tests for the assessment of thrombotic risk or for monitoring the effects of drugs inhibiting platelet function is not well established. Light transmission aggregometry (LTA) is the gold standard for the study of patients with defects of platelet function. Its results are affected by several pre-analytical and analytical variables. The Subcommittee on Platelet Physiology of the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis published official guidelines for the standardization of the variables affecting LTA, which should be followed to harmonize the procedures across different laboratories worldwide. The lumi-aggregometer, a modification of LTA that measures platelet secretion in parallel with aggregation, is preferable to LTA for diagnosing inherited defects of platelet function, because it is more sensitive to the most common disorders, which are characterized by abnormalities of platelet secretion. LTA (or lumi-aggregometry) is useful as a first screening test of patients with the clinical suspicion of defects of platelet function, because it helps to provide an interim diagnostic hypothesis, which can then be confirmed or discounted using appropriate and specific tests. PMID:27426860

  2. Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

    International Nuclear Information System (INIS)

    Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail

  3. Physiopathology of blood platelets and development of platelet substitutes. Progress report, August 1, 1975--July 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, M G

    1976-04-28

    Progress is reported on studies on the physiology of blood platelets in thrombocytopenic patients and rabbits. Methods for the detection of platelet antibodies and the preservation of platelets in vitro were investigated. Studies on the effect of low doses of x irradiation (up to 1000 R) on platelet function indicate that platelets exposed to ionizing radiation have increased functional activity. A list is included of publications that report the results of the studies in detail.

  4. Influence of caffeine on blood pressure and platelet aggregation

    OpenAIRE

    2000-01-01

    OBJECTIVE: Studies have demonstrated that methylxanthines, such as caffeine, are A1 and A2 adenosine receptor antagonists found in the brain, heart, lungs, peripheral vessels, and platelets. Considering the high consumption of products with caffeine in their composition, in Brazil and throughout the rest of the world, the authors proposed to observe the effects of this substance on blood pressure and platelet aggregation. METHODS: Thirteen young adults, ranging from 21 to 27 years of age, par...

  5. Rupture Forces among Human Blood Platelets at different Degrees of Activation.

    Science.gov (United States)

    Nguyen, Thi-Huong; Palankar, Raghavendra; Bui, Van-Chien; Medvedev, Nikolay; Greinacher, Andreas; Delcea, Mihaela

    2016-01-01

    Little is known about mechanics underlying the interaction among platelets during activation and aggregation. Although the strength of a blood thrombus has likely major biological importance, no previous study has measured directly the adhesion forces of single platelet-platelet interaction at different activation states. Here, we filled this void first, by minimizing surface mediated platelet-activation and second, by generating a strong adhesion force between a single platelet and an AFM cantilever, preventing early platelet detachment. We applied our setup to measure rupture forces between two platelets using different platelet activation states, and blockade of platelet receptors. The rupture force was found to increase proportionally to the degree of platelet activation, but reduced with blockade of specific platelet receptors. Quantification of single platelet-platelet interaction provides major perspectives for testing and improving biocompatibility of new materials; quantifying the effect of drugs on platelet function; and assessing the mechanical characteristics of acquired/inherited platelet defects. PMID:27146004

  6. 3H-spiroperidol binding sites in blood platelets

    International Nuclear Information System (INIS)

    3H-spiroperidol, an antagonist of dopamine receptors in brain (striatum), was found to bind to human and rat platelet membrane preparations. The binding was rapid, reversible, saturable and specific. Unlabelled haloperidol displaced the specifically bound 3H-spiroperidol. Binding equilibrium was attained in 15 min at pH 7.4 and 37 degrees C. Scatchard analysis of 3H-spiroperidol binding revealed a single population of binding site with Kd of 7.6 nM in rat platelet membrane and Kd of 15 nM in human platelet membrane. Unlabelled 5-hydroxytryptamine produced no significant effect on 3H-spiroperidol binding to rat or human blood platelet membranes in the presence or absence of haloperidol. Some dopaminergic agents, known to inhibit spiroperidol binding in corpus striatum, also inhibited the same in rat and human blood platelet membranes under in vitro conditions. This study suggests the presence of specific 3H-spiroperidol binding sites in blood platelets

  7. Aluminum induces lipid peroxidation and aggregation of human blood platelets

    Directory of Open Access Journals (Sweden)

    Neiva T.J.C.

    1997-01-01

    Full Text Available Aluminum (Al3+ intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 µM stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA (100 µM and n-propyl gallate (NPG (100 µM, inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA (100 µM, an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation

  8. MYH-9 Related Platelet Disorders: Strategies for Management and Diagnosis

    OpenAIRE

    Althaus, Karina; Greinacher, Andreas

    2010-01-01

    MYH-9 related platelet disorders belong to the group of inherited giant platelet disorders. The MYH-9 gene encodes the non-muscular myosin heavy chain IIA (NMMHCIIA), a cytoskeletal contractile protein. Several mutations in the MYH-9 gene lead to macrothrombocytopenia, and cytoplasmic inclusion bodies within leukocytes, while the number of megakaryocytes in the bone marrow is normal. Four overlapping syndromes, known as May-Hegglin anomaly, Epstein syndrome, Fechtner syndrome and Sebastian pl...

  9. Thrombocytopenia model with minimal manipulation of blood cells allowing whole blood assessment of platelet function.

    Science.gov (United States)

    Tiedemann Skipper, Mette; Rubak, Peter; Halfdan Larsen, Ole; Hvas, Anne-Mette

    2016-06-01

    In vitro models of thrombocytopenia are useful research tools. Previously published models have shortcomings altering properties of platelets and other blood components. The aim of the present study was to develop a whole blood method to induce thrombocytopenia with minimal manipulation, and to describe platelet function in induced thrombocytopenia in individuals with healthy platelets. Hirudin anticoagulated blood was obtained from 20 healthy volunteers. One part of the blood was gently centrifuged at 130g for 15 minutes. The platelet-rich plasma was replaced with phosphate-buffered saline to establish thrombocytopenia. Various levels of thrombocytopenia were achieved by combining different volumes of baseline whole blood and thrombocytopenic blood. Platelet counts were measured by flow cytometry (Navios, Beckman Coulter) and routine haematological analyser (Sysmex XE-5000). Platelet function was analysed by impedance aggregometry (Multiplate® Analyzer, Roche) and by flow cytometry (Navios, Beckman Coulter) using collagen, adenosine diphosphate, thrombin receptor activating peptide-6 and ristocetin as agonists. Median baseline platelet count was 227×10(9)/l. The in vitro model yielded median platelet counts at 51×10(9)/l (range 26-93×10(9)/l). We observed minor, yet significant, changes in platelet size and maturity from baseline to modelled thrombocytopenia. In the thrombocytopenic samples, significant and positive linear associations were found between platelet count and platelet aggregation across all agonists (all p-valuesblood-based model of thrombocytopenia was established and validated. This new model serves as a useful future tool, particularly to explore platelet function in patients with thrombocytopenia. PMID:26555800

  10. Platelet Function in Stored Heparinised Autologous Blood Is Not Superior to in Patient Platelet Function during Routine Cardiopulmonary Bypass

    OpenAIRE

    Gallandat Huet, Rolf C. G.; de Vries, Adrianus J.; Cernak, Vladimir; Lisman, Ton

    2012-01-01

    Background In cardiac surgery, cardiopulmonary bypass (CPB) and unfractionated heparin have negative effects on blood platelet function. In acute normovolemic haemodilution autologous unfractionated heparinised blood is stored ex-vivo and retransfused at the end of the procedure to reduce (allogeneic) transfusion requirements. In this observational study we assessed whether platelet function is better preserved in ex vivo stored autologous blood compared to platelet function in the patient du...

  11. Influence of caffeine on blood pressure and platelet aggregation

    Directory of Open Access Journals (Sweden)

    José Wilson S. Cavalcante

    2000-08-01

    Full Text Available OBJECTIVE: Studies have demonstrated that methylxanthines, such as caffeine, are A1 and A2 adenosine receptor antagonists found in the brain, heart, lungs, peripheral vessels, and platelets. Considering the high consumption of products with caffeine in their composition, in Brazil and throughout the rest of the world, the authors proposed to observe the effects of this substance on blood pressure and platelet aggregation. METHODS: Thirteen young adults, ranging from 21 to 27 years of age, participated in this study. Each individual took 750mg/day of caffeine (250mg tid, over a period of seven days. The effects on blood pressure were analyzed through the pressor test with handgrip, and platelet aggregation was analyzed using adenosine diphosphate, collagen, and adrenaline. RESULTS: Diastolic pressure showed a significant increase 24 hours after the first intake (p<0.05. This effect, however, disappeared in the subsequent days. The platelet aggregation tests did not reveal statistically significant alterations, at any time during the study. CONCLUSION: The data suggest that caffeine increases diastolic blood pressure at the beginning of caffeine intake. This hypertensive effect disappears with chronic use. The absence of alterations in platelet aggregation indicates the need for larger randomized studies.

  12. Contribution of blood platelets to vascular pathology in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Zhang W

    2013-11-01

    Full Text Available Wei Zhang,1,2 Wei Huang,1 Fang Jing11Department of Pharmacology, Institutes for Advanced Interdisciplinary Research, East China Normal University, Shanghai, People's Republic of China; 2Shanghai Engineering Research Center of Molecular Therapy and Pharmaceutical Innovation, Shanghai, People's Republic of ChinaAbstract: Cerebral amyloid angiopathy (CAA is a critical factor in the pathogenesis of Alzheimer's disease (AD. In the clinical setting, nearly 98% AD patients have CAA, and 75% of these patients are rated as severe CAA. It is characterized by the deposition of the β-amyloid peptide (mainly Aβ40 in the walls of cerebral vessels, which induces the degeneration of vessel wall components, reduces cerebral blood flow, and aggravates cognitive decline. Platelets are anuclear cell fragments from bone marrow megakaryocytes and their function in hemostasis and thrombosis has long been recognized. Recently, increasing evidence suggests that platelet activation can also mediate the onset and development of CAA. First, platelet activation and adhesion to a vessel wall is the initial step of vascular injury. Activated platelets contribute to more than 90% circulating Aß (mainly Aβ1-40, which in turn activates platelets and results in the vicious cycle of Aβ overproduction in damaged vessel. Second, the uncontrolled activation of platelets leads to a chronic inflammatory reaction by secretion of chemokines (eg, platelet factor 4 [PF4], regulated upon activation normal T-cell expressed and presumably secreted [RANTES], and macrophage inflammatory protein [MIP-1α], interleukins (IL-1 β, IL-7, and IL-8, prostaglandins, and CD40 ligand (CD40L. The interaction of these biological response modulators with platelets, endothelial cells, and leukocytes establishes a localized inflammatory response that contributes to CAA formation. Finally, activated platelets are the upholder of fibrin clots, which are structurally abnormal and resistant to degradation

  13. Platelet function in stored heparinised autologous blood is not superior to in patient platelet function during routine cardiopulmonary bypass.

    Directory of Open Access Journals (Sweden)

    Rolf C G Gallandat Huet

    Full Text Available BACKGROUND: In cardiac surgery, cardiopulmonary bypass (CPB and unfractionated heparin have negative effects on blood platelet function. In acute normovolemic haemodilution autologous unfractionated heparinised blood is stored ex-vivo and retransfused at the end of the procedure to reduce (allogeneic transfusion requirements. In this observational study we assessed whether platelet function is better preserved in ex vivo stored autologous blood compared to platelet function in the patient during CPB. METHODOLOGY/PRINCIPAL FINDING: We measured platelet aggregation responses pre-CPB, 5 min after the start of CPB, at the end of CPB, and after unfractionated heparin reversal, using multiple electrode aggregometry (Multiplate® with adenosine diphosphate (ADP, thrombin receptor activating peptide (TRAP and ristocetin activated test cells. We compared blood samples taken from the patient with samples taken from 100 ml ex-vivo stored blood, which we took to mimick blood storage during normovolemic haemodilution. Platelet function declined both in ex-vivo stored blood as well as in blood taken from the patient. At the end of CPB there were no differences in platelet aggregation responses between samples from the ex vivo stored blood and the patient. CONCLUSION/SIGNIFICANCE: Ex vivo preservation of autologous blood in unfractionated heparin does not seem to be profitable to preserve platelet function.

  14. Aspirin insensitive thrombophilia: Transcript profiling of blood identifies platelet abnormalities and HLA restriction

    Science.gov (United States)

    Fallahi, Payam; Katz, Richard; Toma, Ian; Li, Ranyang; Reiner, Jonathan; VanHouten, Kiersten; Carpio, Larry; Marshall, Lorraine; Lian, Yi; Bupp, Sujata; Fu, Sidney W.; Rickles, Frederick; Leitenberg, David; Lai, Yinglei; Weksler, Babette B.; Rebling, Frederik; Yang, Zhaoqing; McCaffrey, Timothy A.

    2016-01-01

    Aspirin is the most widely used antiplatelet agent because it is safe, efficient, and inexpensive. However, a significant subset of patients does not exhibit a full inhibition of platelet aggregation, termed ‘aspirin resistance’ (AR). Several major studies have observed that AR patients have a 4-fold increased risk of myocardial infarction (MI), stroke, and other thrombotic events. Arachidonic acid-stimulated whole blood aggregation was tested in 132 adults at risk for ischemic events, and identified an inadequate response to aspirin therapy in 9 patients (6.8%). Expression profiling of blood RNA by microarray was used to generate new hypotheses about the etiology of AR. Among the differentially expressed genes, there were decreases in several known platelet transcripts, including clusterin (CLU), glycoproteins IIb/IIIa (ITGA2B/3), lipocalin (LCN2), lactoferrin (LTF), and the thrombopoetin receptor (MPL), but with increased mRNA for the T-cell Th1 chemokine CXCL10. There was a strong association of AR with expression of HLA-DRB4 and HLA-DQA1. Similar HLA changes have been linked to autoimmune disorders, particularly antiphospholipid syndrome (APS), in which autoantibodies to phospholipid/protein complexes can trigger platelet activation. Consistent with APS, AR patients exhibited a 30% reduction in platelet counts. Follow-up testing for autoimmune antibodies observed only borderline titers in AR patients. Overall, these results suggest that AR may be related to changes in platelet gene expression creating a hyperreactive platelet, despite antiplatelet therapy. Future studies will focus on determining the protein levels of these differential transcripts in platelets, and the possible involvement of HLA restriction as a contributing factor. PMID:23454623

  15. Platelet Factor 4/Heparin Antibodies in Blood Bank Donors

    OpenAIRE

    Hursting, Marcie J; Pai, Poulomi J.; McCracken, Julianna E.; Hwang, Fred; Suvarna, Shayela; Lokhnygina, Yuliya; Bandarenko, Nicholas; Arepally, Gowthami M.

    2010-01-01

    Platelet factor 4 (PF4)/heparin antibody, typically associated with heparin therapy, is reported in some heparin-naive people. Seroprevalence in the general population, however, remains unclear. We prospectively evaluated PF4/heparin antibody in approximately 4,000 blood bank donors using a commercial enzyme-linked immunosorbent assay for initial and then repeated (confirmatory) testing. Antibody was detected initially in 249 (6.6%; 95% confidence interval [CI], 5.8%-7.4%) of 3,795 donors and...

  16. Whole Blood Platelet Aggregation and Release Reaction Testing in Uremic Patients

    OpenAIRE

    Louis DePalma; Lew, Susie Q.; Jason Schallheim; Jay Zeck

    2013-01-01

    Background. Platelet function analysis utilizing platelet-rich plasma and optical density based aggregometry fails to identify patients at risk for uremia associated complications. Methods. We employed whole blood platelet aggregation analysis based on impedance as well as determination of ATP release from platelet granules detected by a chemiluminescence method. Ten chronic kidney disease (CKD) stage 4 or 5 predialysis patients underwent platelet evaluation. Our study aims to evaluate this p...

  17. Microfluidic Flow Chambers Using Reconstituted Blood to Model Hemostasis and Platelet Transfusion In Vitro.

    Science.gov (United States)

    Van Aelst, Britt; Feys, Hendrik B; Devloo, Rosalie; Vandekerckhove, Philippe; Compernolle, Veerle

    2016-01-01

    Blood platelets prepared for transfusion gradually lose hemostatic function during storage. Platelet function can be investigated using a variety of (indirect) in vitro experiments, but none of these is as comprehensive as microfluidic flow chambers. In this protocol, the reconstitution of thrombocytopenic fresh blood with stored blood bank platelets is used to simulate platelet transfusion. Next, the reconstituted sample is perfused in microfluidic flow chambers which mimic hemostasis on exposed subendothelial matrix proteins. Effects of blood donation, transport, component separation, storage and pathogen inactivation can be measured in paired experimental designs. This allows reliable comparison of the impact every manipulation in blood component preparation has on hemostasis. Our results demonstrate the impact of temperature cycling, shear rates, platelet concentration and storage duration on platelet function. In conclusion, this protocol analyzes the function of blood bank platelets and this ultimately aids in optimization of the processing chain including phlebotomy, transport, component preparation, storage and transfusion. PMID:27023054

  18. Silica Nanoparticles Effects on Blood Coagulation Proteins and Platelets

    OpenAIRE

    Volodymyr Gryshchuk; Natalya Galagan

    2016-01-01

    Interaction of nanoparticles with the blood coagulation is important prior to their using as the drug carriers or therapeutic agents. The aim of present work was studying of the primary effects of silica nanoparticles (SiNPs) on haemostasis in vitro. We studied the effect of SiNPs on blood coagulation directly estimating the activation of prothrombin and factor X and to verify any possible effect of SiNPs on human platelets. It was shown that SiNPs shortened coagulation time in APTT and PT te...

  19. Mesoscopic Modeling of Blood Clotting: Coagulation Cascade and Platelets Adhesion

    Science.gov (United States)

    Yazdani, Alireza; Li, Zhen; Karniadakis, George

    2015-11-01

    The process of clot formation and growth at a site on a blood vessel wall involve a number of multi-scale simultaneous processes including: multiple chemical reactions in the coagulation cascade, species transport and flow. To model these processes we have incorporated advection-diffusion-reaction (ADR) of multiple species into an extended version of Dissipative Particle Dynamics (DPD) method which is considered as a coarse-grained Molecular Dynamics method. At the continuum level this is equivalent to the Navier-Stokes equation plus one advection-diffusion equation for each specie. The chemistry of clot formation is now understood to be determined by mechanisms involving reactions among many species in dilute solution, where reaction rate constants and species diffusion coefficients in plasma are known. The role of blood particulates, i.e. red cells and platelets, in the clotting process is studied by including them separately and together in the simulations. An agonist-induced platelet activation mechanism is presented, while platelets adhesive dynamics based on a stochastic bond formation/dissociation process is included in the model.

  20. Thrombin-Mediated Platelet Activation of Lysed Whole Blood and Platelet-Rich Plasma: A Comparison Between Platelet Activation Markers and Ultrastructural Alterations.

    Science.gov (United States)

    Augustine, Tanya N; van der Spuy, Wendy J; Kaberry, Lindsay L; Shayi, Millicent

    2016-06-01

    Platelet ultrastructural alterations representing spurious activation have been identified in pathological conditions. A limitation of platelet studies is that sample preparation may lead to artifactual activation processes which may confound results, impacting the use of scanning electron microscopy as a supplemental diagnostic tool. We used scanning electron microscopy and flow cytometry to analyze platelet activation in platelet-rich plasma (PRP) and whole blood (WB) samples. PRP generated using a single high g force centrifugation, and WB samples treated with a red blood cell lysis buffer, were exposed to increasing concentrations of the agonist thrombin. Platelets in lysed WB samples responded to thrombin by elevating the activation marker CD62p definitively, with corresponding ultrastructural changes indicating activation. Conversely, CD62p expression in PRP preparations remained static. Ultrastructural analysis revealed fully activated platelets even under low concentration thrombin stimulation, with considerable fibrin deposition. It is proposed that the method for PRP production induced premature platelet activation, preventable by using an inhibitor of platelet aggregation and fibrin polymerization. Nevertheless, our results show a definitive correspondence between flow cytometry and scanning electron microscopy in platelet activation studies, highlighting the potential of the latter technique as a supplemental diagnostic tool. PMID:27329313

  1. The organization of microtubules and microtubule coils in giant platelet disorders.

    OpenAIRE

    White, J. G.; Sauk, J. J.

    1984-01-01

    Normal human platelets are characteristically discoid in shape. The lentiform appearance is supported by a circumferential band of microtubules lying just under the cell membrane along its greatest circumference. Some of the cells from patients with giant platelet disorders are also disk-shaped, but the majority of their huge platelets are spherical. In the present study platelets from patients with the Gray platelet syndrome (GPS), May-Hegglin anomaly (MHA), and Epstein's syndrome (ES) were ...

  2. The Influence of Low Platelet Count on Whole Blood Aggregometry Assessed by Multiplate

    DEFF Research Database (Denmark)

    Stissing, Trine; Dridi, Nadia P; Ostrowski, Sisse R; Bochsen, Louise; Johansson, Pär I

    2011-01-01

    in an artificial matrix, platelet-rich plasma (PRP). Heparinized and citrated blood was diluted with autologous plasma to platelet concentrations 200 to 25 × 10(9)/L in WB samples (n = 10) and 200 to 100 × 10(9)/L in PRP samples (n = 7). The platelet aggregation was investigated by the ADP-, ASPI......The Multiplate, a whole blood (WB) platelet function test, has shown promising results identifying patients on antiplatelet therapy at increased risk of rethrombosis. In the present study, the influence of low platelet count on platelet aggregation was analyzed and compared with aggregation results......-, COL-, and TRAP-test. The WB responses decreased at platelet concentration of ≤100 × 10(9)/L (all P <.03), except for heparin-TRAP (50 × 10(9)/L, P = .008) and citrate-ASPI (150 × 10(9)/L, P = .03). In general, WB samples demonstrated higher aggregation than PRP samples at platelet concentrations 200...

  3. The Influence of Low Platelet Count on Whole Blood Aggregometry Assessed by Multiplate

    DEFF Research Database (Denmark)

    Stissing, Trine; Dridi, Nadia P; Ostrowski, Sisse R; Bochsen, Louise; Johansson, Pär I

    2011-01-01

    The Multiplate, a whole blood (WB) platelet function test, has shown promising results identifying patients on antiplatelet therapy at increased risk of rethrombosis. In the present study, the influence of low platelet count on platelet aggregation was analyzed and compared with aggregation results...... in an artificial matrix, platelet-rich plasma (PRP). Heparinized and citrated blood was diluted with autologous plasma to platelet concentrations 200 to 25 × 10(9)/L in WB samples (n = 10) and 200 to 100 × 10(9)/L in PRP samples (n = 7). The platelet aggregation was investigated by the ADP-, ASPI......-, COL-, and TRAP-test. The WB responses decreased at platelet concentration of ≤100 × 10(9)/L (all P <.03), except for heparin-TRAP (50 × 10(9)/L, P = .008) and citrate-ASPI (150 × 10(9)/L, P = .03). In general, WB samples demonstrated higher aggregation than PRP samples at platelet concentrations 200...

  4. The influence of platelets, plasma and red blood cells on functional haemostatic assays

    DEFF Research Database (Denmark)

    Bochsen, Louise; Johansson, Pär I.; Kristensen, Annemarie Thuri; Daugaard, Gedske; Ostrowski, Sisse Rye

    2011-01-01

    , removing plasma from platelet concentrates eliminated the TEG response and diminished the Multiplate aggregation response, but readding plasma to the pure platelet concentrates restored the response. Each of the elements in whole blood, plasma, platelets and RBC, affected the Multiplate and TEG results......Functional whole blood haemostatic assays are used increasingly to guide transfusion therapy and monitor medical treatment and are also applied for in-vitro evaluations of the haemostatic potential of stored platelets. We investigated how the cellular and plasmatic elements, both isolated and...... combined, influenced the two methodologically different assays, thrombelastography (TEG) and impedance aggregometry (Multiplate). Platelet-rich plasma (200 × 10/l) or pure plasma (0 platelets), with and without added red blood cells (RBCs), hematocrit 0, 0.15 or 0.29, were produced in vitro from platelet...

  5. White Blood Cell Disorders

    Science.gov (United States)

    ... where they are needed, and then kill and digest the harmful organism or substance (see White blood ... Patel Hello Everyone! Hello to all of you readers! I know you will be seeing my biography, ...

  6. Venous levels of shear support neutrophil-platelet adhesion and neutrophil aggregation in blood via P-selectin and beta2-integrin

    Science.gov (United States)

    Konstantopoulos, K.; Neelamegham, S.; Burns, A. R.; Hentzen, E.; Kansas, G. S.; Snapp, K. R.; Berg, E. L.; Hellums, J. D.; Smith, C. W.; McIntire, L. V.; Simon, S. I.

    1998-01-01

    BACKGROUND: After activation, platelets adhere to neutrophils via P-selectin and beta2-integrin. The molecular mechanisms and adhesion events in whole blood exposed to venous levels of hydrodynamic shear in the absence of exogenous activation remain unknown. METHODS AND RESULTS: Whole blood was sheared at approximately 100 s(-1). The kinetics of neutrophil-platelet adhesion and neutrophil aggregation were measured in real time by flow cytometry. P-selectin was upregulated to the platelet surface in response to shear and was the primary factor mediating neutrophil-platelet adhesion. The extent of neutrophil aggregation increased linearly with platelet adhesion to neutrophils. Blocking either P-selectin, its glycoprotein ligand PSGL-1, or both simultaneously by preincubation with a monoclonal antibody resulted in equivalent inhibition of neutrophil-platelet adhesion (approximately 30%) and neutrophil aggregation (approximately 70%). The residual amount of neutrophil adhesion was blocked with anti-CD11b/CD18. Treatment of blood with prostacyclin analogue ZK36374, which raises cAMP levels in platelets, blocked P-selectin upregulation and neutrophil aggregation to baseline. Complete abrogation of platelet-neutrophil adhesion required both ZK36374 and anti-CD18. Electron microscopic observations of fixed blood specimens revealed that platelets augmented neutrophil aggregation both by forming bridges between neutrophils and through contact-mediated activation. CONCLUSIONS: The results are consistent with a model in which venous levels of shear support platelet adherence to neutrophils via P-selectin binding PSGL-1. This interaction alone is sufficient to mediate neutrophil aggregation. Abrogation of platelet adhesion and aggregation requires blocking Mac-1 in addition to PSGL-1 or P-selectin. The described mechanisms are likely of key importance in the pathogenesis and progression of thrombotic disorders that are exacerbated by leukocyte-platelet aggregation.

  7. Micro-scale dynamic simulation of erythrocyte-platelet interaction in blood flow.

    Science.gov (United States)

    AlMomani, T; Udaykumar, H S; Marshall, J S; Chandran, K B

    2008-06-01

    Platelet activation, adhesion, and aggregation on the blood vessel and implants result in the formation of mural thrombi. Platelet dynamics in blood flow is influenced by the far more numerous erythrocytes (RBCs). This is particularly the case in the smaller blood vessels (arterioles) and in constricted regions of blood flow (such as in valve leakage and hinge regions) where the dimensions of formed elements of blood become comparable with that of the flow geometry. In such regions, models to predict platelet motion, activation, aggregation and adhesion must account for platelet-RBC interactions. This paper studies platelet-RBC interactions in shear flows by performing simulations of micro-scale dynamics using a computational fluid dynamics (CFD) model. A level-set sharp-interface immersed boundary method is employed in the computations in which RBC and platelet boundaries are tracked on a two-dimensional Cartesian grid. The RBCs are assumed to have an elliptical shape and to deform elastically under fluid forces while the platelets are assumed to behave as rigid particles of circular shape. Forces and torques between colliding blood cells are modeled using an extension of the soft-sphere model for elliptical particles. RBCs and platelets are transported under the forces and torques induced by fluid flow and cell-cell and cell-platelet collisions. The simulations show that platelet migration toward the wall is enhanced with increasing hematocrit, in agreement with past experimental observations. This margination is seen to occur due to hydrodynamic forces rather than collisional forces or volumetric exclusion effects. The effect of fluid shear forces on the platelets increases exponentially as a function of hematocrit for the range of parameters covered in this study. The micro-scale analysis can be potentially employed to obtain a deterministic relationship between fluid forces and platelet activation and aggregation in blood flow past cardiovascular implants

  8. Platelets mediate lymphovenous hemostasis to maintain blood-lymphatic separation throughout life

    OpenAIRE

    Hess, Paul R.; Rawnsley, David R.; Jakus, Zoltán; Yang, Yiqing; Sweet, Daniel T.; Fu, Jianxin; Herzog, Brett; Lu, Minmin; Nieswandt, Bernhard; Oliver, Guillermo; Makinen, Taija; Xia, Lijun; Kahn, Mark L.

    2013-01-01

    Mammals transport blood through a high-pressure, closed vascular network and lymph through a low-pressure, open vascular network. These vascular networks connect at the lymphovenous (LV) junction, where lymph drains into blood and an LV valve (LVV) prevents backflow of blood into lymphatic vessels. Here we describe an essential role for platelets in preventing blood from entering the lymphatic system at the LV junction. Loss of CLEC2, a receptor that activates platelets in response to lymphat...

  9. Scalable evaluation of platelet aggregation by the degree of blood migration

    Science.gov (United States)

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-12-01

    Platelet aggregation plays a key role in vascular thrombosis. Antiplatelet drug therapy is commonly used for the prevention of abnormal platelet aggregation. So, measuring platelet aggregation function is critically important in clinical field. Here, we introduce a scalable evaluation method of platelet aggregation measured with the degree of blood migration through microchannel in a microfluidic chip. Unlike conventional methods that require expertise with system physics to operate devices, our approach is using microfluidics system, which requires only a syringe vacuum. The scalable migration factors, migration distance and touchdown time, are capable of distinguishing various antiplatelet drug effects under microfluidics and would be effective for the quick and easy evaluation of quantitative platelet aggregation.

  10. Platelets in Lung Biology

    Science.gov (United States)

    Weyrich, Andrew S.; Zimmerman, Guy A.

    2013-01-01

    Platelets and the lungs have an intimate relationship. Platelets are anucleate mammalian blood cells that continuously circulate through pulmonary vessels and that have major effector activities in hemostasis and inflammation. The lungs are reservoirs for megakaryocytes, the requisite precursor cell in thrombopoiesis, which is the intricate process by which platelets are generated. Platelets contribute to basal barrier integrity of the alveolar capillaries, which selectively restricts the transfer of water, proteins, and red blood cells out of the vessels. Platelets also contribute to pulmonary vascular repair. Although platelets bolster hemostatic and inflammatory defense of the healthy lung, experimental evidence and clinical evidence indicate that these blood cells are effectors of injury in a variety of pulmonary disorders and syndromes. Newly discovered biological capacities of platelets are being explored in the context of lung defense, disease, and remodeling. PMID:23043249

  11. [Single-donor (apheresis) platelets and pooled whole-blood-derived platelets--significance and assessment of both blood products].

    Science.gov (United States)

    Hitzler, Walter E

    2014-01-01

    The transfusion efficacy of ATK, which contain fully functional platelets, is beyond all doubt. The equivalence of ATK and PTK has been subject of many studies. Some of those studies show the superiority of ATK's, while others do not, but there have been no studies that demonstrated a superiority of PTK's. The superiority of platelets stored in plasma and in third generation additive solution was demonstrated in clinical studies; therefore, it cannot be said that all the platelet concentrates on the German market are equivalent in efficacy. Of decisive importance, above all, is the risk of transfusion-transmitted infections with known pathogens, or those not yet discovered. This risk is different for ATK compared to PTK. Taking this difference in risk and the difference in donor exposure of transfused patients into account, it can definitely be said that ATK and PTK are not equivalent. In 2012, the Robert-Koch-Institute (RKI) published a mathematical risk model for different platelet concentrates and assessed the risk of transmitting known pathogens such as HIV, HCV, and HBV. The risk was higher for PTK compared to ATK. The relative risks for PTK derived from 4BCs were 2.2 (95%--CI: 2.1-2.4) for HIV, 2.7 (95%--CI: 2.5-3.0) for HCV, and 2.2 (95%--CI: 2.8-3.7) for HBV. At the present time, these are the relative risks of transfusion-transmitted infections with the traditional pathogens for PTK compared to ATK. In addition to the RKI assessed risks, there is the theoretical risk of a new, unknown agent, transmitted through blood exposure. The magnitude of this risk is hardly predictable for PTK. The experience gathered so far, especially in the last three decades, with the emergence of HIV, prions, and West Nil virus, shows that the biological nature of a next transfusion-transmissible infectious agent cannot be predictable. This agent, if we think at a conventional sexually transmissible agent with nucleic acid and long latent period, would spread first in areas with

  12. Variability in platelet responses to collagen--comparison between whole blood perfusions, traditional platelet function tests and PFA-100.

    Science.gov (United States)

    Lepäntalo, A; Beer, J H; Siljander, P; Syrjälä, M; Lassila, R

    2001-07-15

    The purpose of this study was to determine if the results obtained in platelet function tests and whole blood perfusions are associated with those in platelet function analyser (PFA)-100. We used collagen type I monomers and fibrils to analyse the distinct roles of glycoprotein (GP) Ia/IIa and other collagen receptors in flowing blood under a high shear rate (1600/s) and in aggregation studies. Also, anticoagulation [citrate vs. D-phenylalanyl-1-prolyl-1 arginine chloromethyl ketone (PPACK)] was varied to enhance the functions of GP Ia/IIa, since it has been shown that the cation-poor environment of citrated blood impairs GP Ia/IIa-dependent platelet recruitment. Large interindividual variability (45-fold) was detected in deposition of platelets in whole blood perfusions over collagen monomers, whereas this variation was only fourfold in fibrils. In PFA, this variation was reduced to 2.5-fold. However, platelet deposition on monomers is associated with epinephrine-enhanced PFA (r=-.49, P<.03), whereas platelet deposition on fibrils is correlated with adenosine diphosphate (ADP)-enhanced PFA (r=-.47, P<.05), suggesting a distinct synergism between epinephrine and monomers (GP Ia/IIa) as well as ADP with fibrils (other collagen receptors). Donors with 807 C/C polymorphism of GP Ia (n=14) had longer lag phase in aggregation experiments compared with C/T (n=7) both by monomers and fibrils (P<.04), but these polymorphisms with their mild impact on GP Ia/IIa activity did not markedly differ in other tests. In conclusion, the results obtained in perfusion studies and PFA experiments correlated, but PFA fails to reveal the large-scale variability related to collagen-induced platelet responses. PMID:11457470

  13. An ethanol extract of Ramulus mori improves blood circulation by inhibiting platelet aggregation.

    Science.gov (United States)

    Lee, Jiyun; Kwon, Gayeung; Park, Jieun; Kim, Jeong-Keun; Choe, Soo Young; Seo, Yoonhee; Lim, Young-Hee

    2016-07-01

    Inappropriate platelet aggregation can cause blood coagulation and thrombosis. In this study, the effect of an ethanol extract of Ramulus mori (ERM) on blood circulation was investigated. The antithrombotic activity of ERM on rat carotid arterial thrombosis was evaluated in vivo, and the effect of ERM on platelet aggregation and blood coagulation time was evaluated ex vivo. To evaluate the safety of ERM, its cytotoxicity to platelets and its effect on tail bleeding time were assessed; ERM was not toxic to rat platelets and did not prolong bleeding time. Moreover, administering ERM to rats had a significant preventive effect on carotid arterial thrombosis in vivo, and significantly inhibited adenosine diphosphate- and collagen-induced platelet aggregation ex vivo, whereas it did not prolong coagulation periods, such as prothrombin time and activated partial thromboplastin time. The results suggest that ERM is effective in improving blood circulation via antiplatelet activity rather than anticoagulation activity. PMID:26967156

  14. Platelet parameters (PLT, MPV, P-LCR) in patients with schizophrenia, unipolar depression and bipolar disorder.

    Science.gov (United States)

    Wysokiński, Adam; Szczepocka, Ewa

    2016-03-30

    There are no studies comparing platelet parameters platelet parameters (platelet count (PLT), mean platelet volume (MPV) and platelet large cell ratio (P-LCR)) between patients with schizophrenia, bipolar disorder and unipolar depression. Therefore, the aim of this study was to determine and compare differences in PLT, MPV and P-LCR in patients with schizophrenia, unipolar depression and bipolar disorder. This was a retrospective, cross-sectional, naturalistic study of 2377 patients (schizophrenia n=1243; unipolar depression n=791; bipolar disorder n=343, including bipolar depression n=259 and mania n=84). There were significant differences for PLT, MPV and P-LCR values between study groups. A significant percentage of patients with bipolar disorder had abnormal (too low or too high) number of platelets. Negative correlation between PLT and age was found in all study groups and positive correlation between age and MPV and P-LCR was found in patients with schizophrenia. PMID:26805563

  15. Platelet impedance aggregation in whole blood and its inhibition by antiplatelet drugs.

    OpenAIRE

    Mackie, I J; Jones, R.; Machin, S. J.

    1984-01-01

    Platelet aggregation was studied in citrated whole blood by an electrical impedance method. Blood samples from normal volunteers were studied with the aim of finding a suitable method for the routine study of samples from patients. An erratic tracing and low maximum aggregation were seen in samples with a high normal haematocrit. Optimal aggregation was seen when blood was diluted to a haematocrit of .300; isotonic saline was a better diluent than platelet poor plasma. No appreciable differen...

  16. Keishibukuryogan, a Traditional Japanese Medicine, Inhibits Platelet Aggregation in Guinea Pig Whole Blood

    OpenAIRE

    Kiyoshi Terawaki; Masamichi Noguchi; Mitsutoshi Yuzurihara; Yuji Omiya; Yasushi Ikarashi; Yoshio Kase

    2015-01-01

    Effects of keishibukuryogan (KBG) on platelet aggregation were investigated. To ensure the specificity of KBG, tokishakuyakusan (TSS) and kamisyoyosan (KSS), which are known to have platelet aggregation-inhibiting effects, and rikkunshito (RKT) and shakuyakukanzoto (SKT), which are considered to be devoid of such effects, were used for comparison. The platelet aggregation of each test drug was measured by the screen filtration pressure method using whole blood of guinea pigs and expressed as ...

  17. Whole Blood Platelet Aggregation and Release Reaction Testing in Uremic Patients

    Directory of Open Access Journals (Sweden)

    Jay Zeck

    2013-01-01

    Full Text Available Background. Platelet function analysis utilizing platelet-rich plasma and optical density based aggregometry fails to identify patients at risk for uremia associated complications. Methods. We employed whole blood platelet aggregation analysis based on impedance as well as determination of ATP release from platelet granules detected by a chemiluminescence method. Ten chronic kidney disease (CKD stage 4 or 5 predialysis patients underwent platelet evaluation. Our study aims to evaluate this platform in this patient population to determine if abnormalities could be detected. Results. Analysis revealed normal aggregation and ATP release to collagen, ADP, and high-dose ristocetin. ATP release had a low response to arachidonic acid (0.37 ± 0.26 nmoles, reference range: 0.6–1.4 nmoles. Platelet aggregation to low-dose ristocetin revealed an exaggerated response (20.9 ± 18.7 ohms, reference range: 0–5 ohms. Conclusions. Whole blood platelet analysis detected platelet dysfunction which may be associated with bleeding and thrombotic risks in uremia. Diminished ATP release to arachidonic acid (an aspirin-like defect in uremic patients may result in platelet associated bleeding. An increased aggregation response to low-dose ristocetin (a type IIb von Willebrand disease-like defect is associated with thrombus formation. This platelet hyperreactivity may be associated with a thrombotic diathesis as seen in some uremic patients.

  18. Developmental endothelial locus-1 modulates platelet-monocyte interactions and instant blood-mediated inflammatory reaction in islet transplantation.

    Science.gov (United States)

    Kourtzelis, Ioannis; Kotlabova, Klara; Lim, Jong-Hyung; Mitroulis, Ioannis; Ferreira, Anaisa; Chen, Lan-Sun; Gercken, Bettina; Steffen, Anja; Kemter, Elisabeth; Klotzsche-von Ameln, Anne; Waskow, Claudia; Hosur, Kavita; Chatzigeorgiou, Antonios; Ludwig, Barbara; Wolf, Eckhard; Hajishengallis, George; Chavakis, Triantafyllos

    2016-04-01

    Platelet-monocyte interactions are strongly implicated in thrombo-inflammatory injury by actively contributing to intravascular inflammation, leukocyte recruitment to inflamed sites, and the amplification of the procoagulant response. Instant blood-mediated inflammatory reaction (IBMIR) represents thrombo-inflammatory injury elicited upon pancreatic islet transplantation (islet-Tx), thereby dramatically affecting transplant survival and function. Developmental endothelial locus-1 (Del-1) is a functionally versatile endothelial cell-derived homeostatic factor with anti-inflammatory properties, but its potential role in IBMIR has not been previously addressed. Here, we establish Del-1 as a novel inhibitor of IBMIR using a whole blood-islet model and a syngeneic murine transplantation model. Indeed, Del-1 pre-treatment of blood before addition of islets diminished coagulation activation and islet damage as assessed by C-peptide release. Consistently, intraportal islet-Tx in transgenic mice with endothelial cell-specific overexpression of Del-1 resulted in a marked decrease of monocytes and platelet-monocyte aggregates in the transplanted tissues, relative to those in wild-type recipients. Mechanistically, Del-1 decreased platelet-monocyte aggregate formation, by specifically blocking the interaction between monocyte Mac-1-integrin and platelet GPIb. Our findings reveal a hitherto unknown role of Del-1 in the regulation of platelet-monocyte interplay and the subsequent heterotypic aggregate formation in the context of IBMIR. Therefore, Del-1 may represent a novel approach to prevent or mitigate the adverse reactions mediated through thrombo-inflammatory pathways in islet-Tx and perhaps other inflammatory disorders involving platelet-leukocyte aggregate formation. PMID:26676803

  19. Estimation of anti-platelet drugs on human platelet aggregation with a novel whole blood aggregometer by a screen filtration pressure method

    OpenAIRE

    Sudo, Toshiki; Ito, Hideki; Ozeki, Yasushi; Kimura, Yukio

    2001-01-01

    The effects of anti-platelet drugs on human whole blood aggregation were evaluated using a novel whole blood aggregometer by a screen filtration pressure (SFP) method.The SFP whole blood aggregometer was found to successfully detect whole blood aggregation induced by ADP, collagen and TRAP by measuring the SFP of blood samples. The platelet aggregation threshold index (PATI), the concentration of agonist required with an inducing pressure rate of 50%, varied time-dependently after collection ...

  20. Blood coagulation parameters and platelet indices: changes in normal and preeclamptic pregnancies and predictive values for preeclampsia.

    Directory of Open Access Journals (Sweden)

    Lei Han

    Full Text Available Preeclampsia (PE is an obstetric disorder with high morbidity and mortality rates but without clear pathogeny. The dysfunction of the blood coagulation-fibrinolysis system is a salient characteristic of PE that varies in severity, and necessitates different treatments. Therefore, it is necessary to find suitable predictors for the onset and severity of PE.We aimed to evaluate blood coagulation parameters and platelet indices as potential predictors for the onset and severity of PE.Blood samples from 3 groups of subjects, normal pregnant women (n = 79, mild preeclampsia (mPE (n = 53 and severe preeclampsia (sPE (n = 42, were collected during early and late pregnancy. The levels of coagulative parameters and platelet indices were measured and compared among the groups. The receiver-operating characteristic (ROC curves of these indices were generated, and the area under the curve (AUC was calculated. The predictive values of the selected potential parameters were examined in binary regression analysis.During late pregnancy in the normal pregnancy group, the activated partial thromboplastin time (APTT, prothrombin time (PT, thrombin time (TT and platelet count decreased, while the fibrinogen level and mean platelet volume (MPV increased compared to early pregnancy (p<0.05. However, the PE patients presented with increased APTT, TT, MPV and D-dimer (DD during the third trimester. In the analysis of subjects with and without PE, TT showed the largest AUC (0.743 and high predictive value. In PE patients with different severities, MPV showed the largest AUC (0.671 and ideal predictive efficiency.Normal pregnancy causes a maternal physiological hypercoagulable state in late pregnancy. PE may trigger complex disorders in the endogenous coagulative pathways and consume platelets and FIB, subsequently activating thrombopoiesis and fibrinolysis. Thrombin time and MPV may serve as early monitoring markers for the onset and severity of PE

  1. Platelet aggregation test

    Science.gov (United States)

    The platelet aggregation blood test checks how well platelets , a part of blood, clump together and cause blood to clot. ... Decreased platelet aggregation may be due to: Autoimmune ... Fibrin degradation products Inherited platelet function defects ...

  2. Modeling HIV-1 Induced Neuroinflammation in Mice: Role of Platelets in Mediating Blood-Brain Barrier Dysfunction.

    Directory of Open Access Journals (Sweden)

    Letitia D Jones

    Full Text Available The number of HIV-1 positive individuals developing some form of HIV-associated neurocognitive disorder (HAND is increasing. In these individuals, the integrity of the blood-brain barrier (BBB is compromised due to an increase in exposure to pro-inflammatory mediators, viral proteins, and virus released from infected cells. It has been shown that soluble CD40L (sCD40L is released upon platelet activation and is an important mediator of the pathogenesis of HAND but the underlying mechanisms are unclear, emphasizing the need of an effective animal model. Here, we have utilized a novel animal model in which wild-type (WT mice were infected with EcoHIV; a derivative of HIV-1 that contains a substitution of envelope protein gp120 with that of gp80 derived from murine leukemia virus-1 (MuLV-1. As early as two-weeks post-infection, EcoHIV led to increased permeability of the BBB associated with decreased expression of tight junction protein claudin-5, in CD40L and platelet activation-dependent manner. Treatment with an antiplatelet drug, eptifibatide, in EcoHIV-infected mice normalized BBB function, sCD40L release and platelet activity, thus implicating platelet activation and platelet-derived CD40L in virally induced BBB dysfunction. Our results also validate and underscore the importance of EcoHIV infection mouse model as a tool to explore therapeutic targets for HAND.

  3. Functional aspects of blood platelets in irradiated burros

    International Nuclear Information System (INIS)

    In irradiated burros (Equus asinus), a delayed clinical syndrome characterized by a depletion of megakarocytes and platelets has been observed. To clarify the cause of this syndrome, the functional abilities of platelets in 7 irradiated and 3 control burros were studied in vitro. The irradiated burros were survivors (> 18 years) of total-body exposures to near-lethal doses of γ-radiation. Burro platelet aggregability induced with adenosine diphosphate and thrombin, and with a complex stimulator from burro aortas, was determined by means of a self-calibrating aggregometer. Data indicated that the aggregation responsiveness to adenosine diphosphate and thrombin of platelets from surviving irradiated and unirradiated burros is not defective. An extractible collagen-like stimulator of platelet aggregation was discovered in the aorta of a burro that had survived > 24 years after exposure to a total-body dose of 545 roentgens (R) of tantalum-182 γ-radiation. The platelet-aggregating ability of this stimulator from the vessel wall of the irradiated burro was nearly fourfold greater than that from the aorta of an unirradiated control. Perhaps a delayed radiation effect could be the cause of this vascular agent's high platelet-aggregating ability and could lead to a clinical syndrome marked by depletion of megakaryocytes and platelets

  4. Three-dimensional multi-scale model of deformable platelets adhesion to vessel wall in blood flow.

    Science.gov (United States)

    Wu, Ziheng; Xu, Zhiliang; Kim, Oleg; Alber, Mark

    2014-08-01

    When a blood vessel ruptures or gets inflamed, the human body responds by rapidly forming a clot to restrict the loss of blood. Platelets aggregation at the injury site of the blood vessel occurring via platelet-platelet adhesion, tethering and rolling on the injured endothelium is a critical initial step in blood clot formation. A novel three-dimensional multi-scale model is introduced and used in this paper to simulate receptor-mediated adhesion of deformable platelets at the site of vascular injury under different shear rates of blood flow. The novelty of the model is based on a new approach of coupling submodels at three biological scales crucial for the early clot formation: novel hybrid cell membrane submodel to represent physiological elastic properties of a platelet, stochastic receptor-ligand binding submodel to describe cell adhesion kinetics and lattice Boltzmann submodel for simulating blood flow. The model implementation on the GPU cluster significantly improved simulation performance. Predictive model simulations revealed that platelet deformation, interactions between platelets in the vicinity of the vessel wall as well as the number of functional GPIbα platelet receptors played significant roles in platelet adhesion to the injury site. Variation of the number of functional GPIbα platelet receptors as well as changes of platelet stiffness can represent effects of specific drugs reducing or enhancing platelet activity. Therefore, predictive simulations can improve the search for new drug targets and help to make treatment of thrombosis patient-specific. PMID:24982253

  5. Portable dynamic light scattering instrument and method for the measurement of blood platelet suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Maurer-Spurej, Elisabeth [Canadian Blood Services and Department of Pathology and Laboratory Medicine and Centre for Blood Research, University of British Columbia, Vancouver, BC (Canada); Brown, Keddie [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada); Labrie, Audrey [Canadian Blood Services and Department of Pathology and Laboratory Medicine and Centre for Blood Research, University of British Columbia, Vancouver, BC (Canada); Marziali, Andre [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada); Glatter, Otto [Institute of Chemistry, Karl-Franzens University, Graz (Austria)

    2006-08-07

    No routine test exists to determine the quality of blood platelet transfusions although every year millions of patients require platelet transfusions to survive cancer chemotherapy, surgery or trauma. A new, portable dynamic light scattering instrument is described that is suitable for the measurement of turbid solutions of large particles under temperature-controlled conditions. The challenges of small sample size, short light path through the sample and accurate temperature control have been solved with a specially designed temperature-controlled sample holder for small diameter, disposable capillaries. Efficient heating and cooling is achieved with Peltier elements in direct contact with the sample capillary. Focusing optical fibres are used for light delivery and collection of scattered light. The practical use of this new technique was shown by the reproducible measurement of latex microspheres and the temperature-induced morphological changes of human blood platelets. The measured parameters for platelet transfusions are platelet size, number of platelet-derived microparticles and the response of platelets to temperature changes. This three-dimensional analysis provides a high degree of confidence for the determination of platelet quality. The experimental data are compared to a matrix and facilitate automated, unbiased quality testing.

  6. Interaction of inorganic nanoparticles of lunar soil simulant with blood platelets

    Science.gov (United States)

    Borisova, Tatiana; Kasatkina, Ludmila; Krisanova, Natalia; Sivko, Roman; Borisov, Arseniy; Slenzka, Klaus

    Blood platelets play a central role in the physiology of primary hemostasis and in the patholog-ical processes of arterial thrombosis. Also, blood platelets contain neuronal high-affinity Na+-dependent glutamate transporters (EAAT 1 -3) and are able to uptake glutamate, thereby playing possible physiological role in extracellular glutamate homeostasis in the mammalian CNS as an additional powerful target for excessive neurotoxic glutamate accumulation and storage. The health effects of lunar soil exposure are almost completely unknown, whereas the observations suggest that it can be deleterious to human physiology. It is important that the components of lunar soil may be internalized with lipid fractions of the lung epithelium, which in turn may help ions to overcome the blood-brain barrier. The study focused on the effects of JSC-1a Lunar Soil Simulant (LSS) (Orbital Technologies Corporation, Madison, USA) on platelets isolated from rabbit blood. We revealed that platelets were not indifferent to the expo-sure to LSS. Flow cytometric analysis showed that the incubation of platelets with LSS resulted in an upper shift of platelet spot in histograms presenting cell size (FS) and granularity (SS) as x and y coordinates, thereby demonstrating apparent increase in platelet granularity. Analysis of control platelet preparation did not reveal the alterations in platelet size and granularity during the same incubation period. LSS scatter per se did not cover area of platelet prepara-tion in histogram. Using Zetasizer Nanosystem (Malvern Instruments) with helium-neon laser for dynamic light scattering (DLS), the platelet size before and after the addition of LSS was measured. We have found the increase in the mean size of the population of platelets from 2.45 ±0.09 µm in control to 3.0 ± 0.25 µm in the presence of LSS. Thus, we report that inorganic nanoparticles of LSS bind to blood platelets and this fact may have considerable harmful conse-quences to human

  7. Platelets

    Science.gov (United States)

    ... on the left. They are shaped like a plate, therefore their name. When platelets are stimulated by ... can occur, related to a restaurant or a contaminated food or water source. Shiga toxin can cause ...

  8. Evaluation of the response of cortisol, corticotropin and blood platelets kinetics after laparoscopic and open cholecystectomy

    OpenAIRE

    Crema Eduardo; Ribeiro Elisangela Neto; Hial Ana Marcela; Alves Júnior Juverson Terra; Pastore Ricardo; Silva Alex Augusto

    2005-01-01

    PURPOSE: To compare the behavior of serum cortisol and ACTH levels and platelet kinetics after laparoscopic and open cholecystectomy. METHODS: In this prospective study, 31 patients with symptomatic cholelithiasis submitted to elective cholecystectomy, 17 by the laparoscopic route and 14 by the open route, were compared. Peripheral blood samples were collected on admission of the patient, during anesthetic induction, and 2, 6, 12, 24 and 48 hours after the surgical incision. Platelets were co...

  9. Sub-cellular modeling of platelet transport in blood flow through microchannels with constriction.

    Science.gov (United States)

    Yazdani, Alireza; Karniadakis, George Em

    2016-05-11

    Platelet transport through arterial constrictions is one of the controlling processes influencing their adhesive functions and the formation of thrombi. We perform high-fidelity mesoscopic simulations of blood flow in microchannels with constriction, resembling arterial stenoses. The wall shear rates inside the constrictions reach levels as high as ≈8000 s(-1), similar to those encountered in moderate atherosclerotic plaques. Both red blood cells and platelets are resolved at sub-cellular resolution using the Dissipative Particle Dynamics (DPD) method. We perform a systematic study on the red blood cell and platelet transport by considering different levels of constriction, blood hematocrit and flow rates. We find that higher levels of constriction and wall shear rates lead to significantly enhanced margination of platelets, which may explain the experimental observations of enhanced post-stenosis platelet aggregation. We also observe similar margination effects for stiff particles of spherical shapes such as leukocytes. To our knowledge, such numerical simulations of dense blood through complex geometries have not been performed before, and our quantitative findings could shed new light on the associated physiological processes such as ATP release, plasma skimming, and thrombus formation. PMID:27087267

  10. Identification of D1-like dopamine receptors on human blood platelets

    International Nuclear Information System (INIS)

    Dopamine is able to inhibit the epinephrine-induced aggregation of human blood platelets, but the mechanism of action has not been elucidated. In this study the authors report that membranes from human blood platelets possess high affinity, saturable and stereoselective binding sites for the D1 dopamine receptor antagonist (3H)SCH 23390. (3H)SCH 23390 appeared to label a single class of binding sites with a B/sub max/ of 18.6 +- 1.6 fmolmg protein and a K/sub D/ of 0.8 nM. The potencies of different dopaminergic antagonists and agonists in displacing (3H)SCH 23390 from blood platelet membranes were similar to those obtained for striatal membranes. Unlike the classically defined D1 receptors, e.g. those in striatum, the D1 receptor sites on platelets appeared no to be coupled to the adenylate cyclase system, hence the term D1-like. The D1 agonist SKF 38393 was more potent than dopamine in inhibiting platelet aggregation induced by epinephrine, and the effects of dopamine and SKF 38393 were prevented by SCH 23390. These results suggest that the inhibitory action of dopamine on the epinephrine-induced platelet aggregation is mediated through these D1-like receptors

  11. Fabricating bio-inspired micro/nano-particles by polydopamine coating and surface interactions with blood platelets

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Wei [Jiangsu Provincial Key Lab for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003 (China); State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Shi, Qiang, E-mail: shiqiang@ciac.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Hou, Jianwen; Gao, Jian; Li, Chunming; Jin, Jing; Shi, Hengchong [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Yin, Jinghua, E-mail: yinjh@ciac.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2015-10-01

    Graphical abstract: The particles or particle aggregations activate the blood platelets and provide the physical adhesive sites for platelets adhesion. - Highlights: • Particles with varied sizes and surface properties were fabricated by facile polydopamine (PDA) coating on polystyrene microsphere. • The direct interaction between PDA particles and blood platelets was qualitatively investigated. • The knowledge on platelet–particle interactions provided the basic principle to select biocompatible micro/nano-particles in biomedical field. - Abstract: Although bio-inspired polydopamine (PDA) micro/nano-particles show great promise for biomedical applications, the knowledge on the interactions between micro/nano-particles and platelets is still lacking. Here, we fabricate PDA-coated micro/nano-particles and investigate the platelet–particle surface interactions. Our strategy takes the advantage of facile PDA coating on polystyrene (PS) microsphere to fabricate particles with varied sizes and surface properties, and the chemical reactivity of PDA layers to immobilize fibrinogen and bovine serum albumin to manipulate platelet activation and adhesion. We demonstrate that PS particles activate the platelets in the size-dependent manner, but PDA nanoparticles have slight effect on platelet activation; PS particles promote platelet adhesion while PDA particles reduce platelet adhesion on the patterned surface; Particles interact with platelets through activating the glycoprotein integrin receptor of platelets and providing physical sites for initial platelet adhesion. Our work sheds new light on the interaction between platelets and particles, which provides the basic principle to select biocompatible micro/nano-particles in biomedical field.

  12. Fabricating bio-inspired micro/nano-particles by polydopamine coating and surface interactions with blood platelets

    International Nuclear Information System (INIS)

    Graphical abstract: The particles or particle aggregations activate the blood platelets and provide the physical adhesive sites for platelets adhesion. - Highlights: • Particles with varied sizes and surface properties were fabricated by facile polydopamine (PDA) coating on polystyrene microsphere. • The direct interaction between PDA particles and blood platelets was qualitatively investigated. • The knowledge on platelet–particle interactions provided the basic principle to select biocompatible micro/nano-particles in biomedical field. - Abstract: Although bio-inspired polydopamine (PDA) micro/nano-particles show great promise for biomedical applications, the knowledge on the interactions between micro/nano-particles and platelets is still lacking. Here, we fabricate PDA-coated micro/nano-particles and investigate the platelet–particle surface interactions. Our strategy takes the advantage of facile PDA coating on polystyrene (PS) microsphere to fabricate particles with varied sizes and surface properties, and the chemical reactivity of PDA layers to immobilize fibrinogen and bovine serum albumin to manipulate platelet activation and adhesion. We demonstrate that PS particles activate the platelets in the size-dependent manner, but PDA nanoparticles have slight effect on platelet activation; PS particles promote platelet adhesion while PDA particles reduce platelet adhesion on the patterned surface; Particles interact with platelets through activating the glycoprotein integrin receptor of platelets and providing physical sites for initial platelet adhesion. Our work sheds new light on the interaction between platelets and particles, which provides the basic principle to select biocompatible micro/nano-particles in biomedical field

  13. A laser flow aggregometer for measurement of white blood cell and platelet aggregation

    International Nuclear Information System (INIS)

    The measurement of aggregation of white blood cells and platelets is important in understanding cardiovascular disease. A new aggregometer has been developed, based on a laser flow cytometer. Pulses detected using a high speed photodiode are acquired to a computer and analysed. Tests based on separated white cells, platelets and whole blood samples have been carried out to evaluate this system. Results show that the laser flow cytometer system has a much better resolution and wider dynamic range than existing electronic flow cytometer instruments. As a result, more details of platelet and white blood cell aggregation profiles can be obtained. The new aggregometer is now being used in clinical trials on patients with vascular disease, for comparison with commercial systems. (author)

  14. The in vitro effect of aspirin on increased whole blood platelet aggregation in oral contraceptive users.

    Science.gov (United States)

    Norris, L A; Bonnar, J

    1994-05-01

    The effects of triphasic oral contraceptives on whole blood platelet aggregation in 36 Italian women are reported here. Aspirin's effects on platelet aggregation were also studied. 18 women took a triphasic oral contraceptive; 10 women took Trinordiol, while 8 took Trinovum for at least 90 days. The remaining 18 women took nothing and served as controls. The study was aligned with each woman's birth control pill cycle. Blood was taken daily on days 15-21 of their cycle. Either saline solution or acetylsalicylic acid was added to the blood samples and compared. All data was statistically analyzed using unpaired student's t-test. Effects of 3 aggregating agents, ADP, PAF, and EDTA, on platelet aggregation were studied. Arachidonic acid and adrenalin bitartrate were also studied in this manner. An increase in platelet aggregation was observed in women taking oral contraceptives. No difference was found between patients taking Trinordiol and those taking Trinovum. The results of this study indicate an increase in whole blood platelet sensitivity to collagen, adrenalin, and arachidonic acid when using oral contraceptives. Aspirin, at low doses, may have a role in preventing early thrombus formation in women taking oral contraceptives. PMID:8042198

  15. Ehlers-danlos syndrome with platelet aggregation defect-presenting as mysterious bleeding disorder

    Directory of Open Access Journals (Sweden)

    Sawhney M

    2003-03-01

    Full Text Available A 7-year-old girl presented with recurrent episodes of petechiae, purpura and ecchymoses since six months of age and recurrent episodes of mild to severe epistaxis since two years of age requiring repeated blood transfusions. In April '99 while being investigated for a massive epistaxis, she was found to have platelet function defect with abnormal aggregation of platelets to ADP, epinephrine, collagen as well as to ristocetin. Further investigations ruled out the possibility of Glanzmann's disorder and von-Willebrand's disease as to its cause. In May 2001 she was referred to the dermatologist for evaluation of subcutaneous tumours, which had developed since the last six months. On clinical evaluation, she was found to be having mild hyperextensibility of the skin, joint hypermobility, atrophic scars over knee, spontaneous bruises over right forearm and left thigh and nontender firm to hard subcutaneous nodules over both wrists, both shoulders, right index finger and dorsum of right foot consistent with a clinical picture of a mild form of Ehlers-Danlos syndrome (EDS. Histopathology of the nodule from left wrist was consistent with molluscoid tumour of EDS and skin histopathology and ultrastructure studies showed thick irregular collagen fibrils. Only other sibling, a five-year-old male also had history of repeated mild to moderate epistaxis and on examination was found to have a milder variant of EDS. Born out of I degree consanguineous marriage of normal parents with mildly affected other sibling, she was diagnosed to be suffering from EDS with autosomal recessive inheritance, most probably EDS type X due to the associated platelet aggregation defect. Only one such family with EDS type X has been reported so far.

  16. Ehlers-danlos syndrome with platelet aggregation defect-presenting as mysterious bleeding disorder

    Directory of Open Access Journals (Sweden)

    Sawhney M

    2003-01-01

    Full Text Available A 7-year-old girl presented with recurrent episodes of petechiae, purpura and ecchymoses since six months of age and recurrent episodes of mild to severe epistaxis since two years of age requiring repeated blood transfusions. In April '99 while being investigated for a massive epistaxis, she was found to have platelet function defect with abnormal aggregation of platelets to ADP, epinephrine, collagen as well as to ristocetin. Further investigations ruled out the possibility of Glanzmann's disorder and von-Willebrand's disease as to its cause. In May 2001 she was referred to the dermatologist for evaluation of subcutaneous tumours, which had developed since the last six months. On clinical evaluation, she was found to be having mild hyperextensibility of the skin, joint hypermobility, atrophic scars over knee, spontaneous bruises over right forearm and left thigh and nontender firm to hard subcutaneous nodules over both wrists, both shoulders, right index finger and dorsum of right foot consistent with a clinical picture of a mild form of Ehlers-Danlos syndrome (EDS. Histopathology of the nodule from left wrist was consistent with molluscoid tumour of EDS and skin histopathology and ultrastructure studies showed thick irregular collagen fibrils. Only other sibling, a five-year-old male also had history of repeated mild to moderate epistaxis and on examination was found to have a milder variant of EDS. Born out of I degree consanguineous marriage of normal parents with mildly affected other sibling, she was diagnosed to be suffering from EDS with autosomal recessive inheritance, most probably EDS type X due to the associated platelet aggregation defect. Only one such family with EDS type X has been reported so far.

  17. Blood disorders typically associated with renal transplantation.

    Science.gov (United States)

    Yang, Yu; Yu, Bo; Chen, Yun

    2015-01-01

    Renal transplantation has become one of the most common surgical procedures performed to replace a diseased kidney with a healthy kidney from a donor. It can help patients with kidney failure live decades longer. However, renal transplantation also faces a risk of developing various blood disorders. The blood disorders typically associated with renal transplantation can be divided into two main categories: (1) Common disorders including post-transplant anemia (PTA), post-transplant lymphoproliferative disorder (PTLD), post-transplant erythrocytosis (PTE), and post-transplant cytopenias (PTC, leukopenia/neutropenia, thrombocytopenia, and pancytopenia); and (2) Uncommon but serious disorders including hemophagocytic syndrome (HPS), thrombotic microangiopathy (TMA), therapy-related myelodysplasia (t-MDS), and therapy-related acute myeloid leukemia (t-AML). Although many etiological factors involve the development of post-transplant blood disorders, immunosuppressive agents, and viral infections could be the two major contributors to most blood disorders and cause hematological abnormalities and immunodeficiency by suppressing hematopoietic function of bone marrow. Hematological abnormalities and immunodeficiency will result in severe clinical outcomes in renal transplant recipients. Understanding how blood disorders develop will help cure these life-threatening complications. A potential therapeutic strategy against post-transplant blood disorders should focus on tapering immunosuppression or replacing myelotoxic immunosuppressive drugs with lower toxic alternatives, recognizing and treating promptly the etiological virus, bacteria, or protozoan, restoring both hematopoietic function of bone marrow and normal blood counts, and improving kidney graft survival. PMID:25853131

  18. Diminished adhesion and activation of platelets and neutrophils with CD47 functionalized blood contacting surfaces.

    Science.gov (United States)

    Finley, Matthew J; Rauova, Lubica; Alferiev, Ivan S; Weisel, John W; Levy, Robert J; Stachelek, Stanley J

    2012-08-01

    CD47 is a ubiquitously expressed transmembrane protein that, through signaling mechanisms mediated by signal regulatory protein alpha (SIRPα1), functions as a biological marker of 'self-recognition'. We showed previously that inflammatory cell attachment to polymeric surfaces is inhibited by the attachment of biotinylated recombinant CD47 (CD47B). We test herein the hypothesis that CD47 modified blood conduits can reduce platelet and neutrophil activation under clinically relevant conditions. We appended a poly-lysine tag to the C-terminus of recombinant CD47 (CD47L) allowing for covalent linkage to the polymer. SIRPα1 expression was confirmed in isolated platelets. We then compared biocompatibility between CD47B and CD47L functionalized polyvinyl chloride (PVC) surfaces and unmodified control PVC surfaces. Quantitative and Qualitative analysis of blood cell attachment to CD47B and CD47L surfaces, via scanning electron microscopy, showed strikingly fewer platelets attached to CD47 modified surfaces compared to control. Flow cytometry analysis showed that activation markers for neutrophils (CD62L) and platelets (CD62P) exposed to CD47 modified PVC were equivalent to freshly acquired control blood, while significantly elevated in the unmodified PVC tubing. In addition, ethylene oxide gas sterilization did not inhibit the efficacy of the CD47 modification. In conclusion, CD47 modified PVC inhibits both the adhesion and activation of platelets and neutrophils. PMID:22613135

  19. Drag-reducing polymers diminish near-wall concentration of platelets in microchannel blood flow

    OpenAIRE

    Zhao, R.; Marhefka, J.N.; Antaki, J.F.; Kameneva, M.V.

    2010-01-01

    The accumulation of platelets near the blood vessel wall or artificial surface is an important factor in the cascade of events responsible for coagulation and/or thrombosis. In small blood vessels and flow channels this phenomenon has been attributed to the blood phase separation that creates a red blood cell (RBC)-poor layer near the wall. We hypothesized that blood soluble drag-reducing polymers (DRP), which were previously shown to lessen the near-wall RBC depletion layer in small channels...

  20. Classical scrapie prions in ovine blood are associated with B lymphocytes and platelet-rich plasma

    Directory of Open Access Journals (Sweden)

    Dassanayake Rohana P

    2011-11-01

    Full Text Available Abstract Background Classical scrapie is a naturally occurring transmissible spongiform encephalopathy of sheep and goats characterized by cellular accumulation of abnormal isoforms of prion protein (PrPSc in the central nervous system and the follicles of peripheral lymphoid tissues. Previous studies have shown that the whole blood and buffy coat blood fraction of scrapie infected sheep harbor prion infectivity. Although PrPSc has been detected in peripheral blood mononuclear cells (PBMCs, plasma, and more recently within a subpopulation of B lymphocytes, the infectivity status of these cells and plasma in sheep remains unknown. Therefore, the objective of this study was to determine whether circulating PBMCs, B lymphocytes and platelets from classical scrapie infected sheep harbor prion infectivity using a sheep bioassay. Results Serial rectal mucosal biopsy and immunohistochemistry were used to detect preclinical infection in lambs transfused with whole blood or blood cell fractions from preclinical or clinical scrapie infected sheep. PrPSc immunolabeling was detected in antemortem rectal and postmortem lymphoid tissues from recipient lambs receiving PBMCs (15/15, CD72+ B lymphocytes (3/3, CD21+ B lymphocytes (3/3 or platelet-rich plasma (2/3 fractions. As expected, whole blood (11/13 and buffy coat (5/5 recipients showed positive PrPSc labeling in lymphoid follicles. However, at 549 days post-transfusion, PrPSc was not detected in rectal or other lymphoid tissues in three sheep receiving platelet-poor plasma fraction. Conclusions Prion infectivity was detected in circulating PBMCs, CD72+ pan B lymphocytes, the CD21+ subpopulation of B lymphocytes and platelet-rich plasma of classical scrapie infected sheep using a sheep bioassay. Combining platelets with B lymphocytes might enhance PrPSc detection levels in blood samples.

  1. Clinical and laboratory characteristics of adolescents with platelet function disorders and heavy menstrual bleeding

    Directory of Open Access Journals (Sweden)

    Amesse Lawrence S

    2013-01-01

    Full Text Available Abstract Background Platelet function disorders (PFDs have emerged as an important etiology of heavy menstrual bleeding (HMB in adolescents. However, neither clinical nor laboratory data have been methodically analyzed in this population subset. The objective of this study was to evaluate these parameters in order to distinguish characteristics of the disorder that in turn will lead to earlier diagnosis and therapy initiation. Methods Retrospective review of medical records from postmenarcheal adolescents with documented PFDs referred to a hemophilia treatment center and university faculty practices for bleeding diatheses with their clinical and laboratory data evaluated. Results Of 63 teens with documented PFDs, HMB was the most common clinical manifestation of PFD (43; 68.3%. Of these, 37 (86% were diagnosed with PFD either at or after menarche with the diagnosis based on HMB symptoms alone. Only 6 (14% were diagnosed with a PFD prior to menarche, based on associated bleeding, i.e., epistaxis, ecchymosis, and all developed HMB after menstruation onset. Interestingly, 20 girls were diagnosed with a PFD prior to menarche and of these, only 6 (30% went on to develop HMB after pubertal transition, while the majority (14; 70% did not. The average age-at-PFD diagnosis was 14.5yrs, significantly differing from the 10.9yrs average age-at-PFD diagnosis in their counterparts that, after menarche, did not develop HMB (PP P Conclusions Adolescents with PFDs and HMB appear to be clinically distinct from their non-HMB counterparts. This group of girls is characterized by HMB the major bleeding symptom, significantly high incidences of blood group O and the δ-SPD with a PFD diagnosed well after menarche. High false negative standard platelet function study results indicate additional diagnostic strategies, particularly for δ-SPD, should be considered.

  2. The influence of Rubus idaeus and Rubus caesius leaf extracts on platelet aggregation in whole blood. Cross-talk of platelets and neutrophils.

    Science.gov (United States)

    Dudzinska, Dominika; Bednarska, Katarzyna; Boncler, Magdalena; Luzak, Boguslawa; Watala, Cezary

    2016-07-01

    Recently, polyphenols have gained attention as potential natural cardioprotective therapeutics, due to their antiplatelet, anti-inflammatory and anticoagulant activity. Species belonging to the genus Rubus sp. have been reported to be a source of polyphenolic compounds with antioxidative proprieties and beneficial biological activities. This study investigates the effects of leaf extracts obtained from red raspberry (Rubus idaeus L.) and European dewberry (Rubus caesius L.) on the reactivity of blood platelets. In ADP-stimulated blood, raspberry and dewberry extracts (15 µg/ml) markedly decreased platelet surface membrane expression of activated GPIIbIIIa receptor by 16% and 21%, respectively (P aggregation (by 31-41% for raspberry and by 38-55% for dewberry, P aggregation. The effectiveness of the extracts in whole blood and the lack of their activity in PRP indicate that leukocytes are likely to participate in the platelet response to the extracts. Our experiments show that the extracts significantly reduced the amount of free radicals released by activated neutrophils in whole blood (P aggregation. In summary, our findings show that the raspberry and dewberry leaf extracts considerably modulated blood platelet reactivity in whole blood: they influenced blood platelet aggregation, possibly via the modulation of the redox status dependent on the oxidative activity of neutrophils. PMID:26836594

  3. Effect of catheter flush fluids on blood coagulation and aggregation of platelets

    International Nuclear Information System (INIS)

    The effect upon blood coagulation and aggregation of platelets of a polysaccharide catheter flush fluid (flush fluid E) was investigated and compared with isotonic saline and Isopaque Cerebral. The result indicates that flush fluid E does not activate the coagulation system. (Auth.)

  4. Evaluation of different sized blood sampling tubes for thromboelastometry, platelet function, and platelet count

    DEFF Research Database (Denmark)

    Andreasen, Jo Bønding; Pistor-Riebold, Thea Unger; Knudsen, Ingrid Hell;

    2014-01-01

    Background: To minimise the volume of blood used for diagnostic procedures, especially in children, we investigated whether the size of sample tubes affected whole blood coagulation analyses. Methods: We included 20 healthy individuals for rotational thromboelastometry (RoTEM®) analyses and compa...

  5. Multiscale Particle-Based Modeling of Flowing Platelets in Blood Plasma Using Dissipative Particle Dynamics and Coarse Grained Molecular Dynamics

    Science.gov (United States)

    Zhang, Peng; Gao, Chao; Zhang, Na; Slepian, Marvin J.; Deng, Yuefan; Bluestein, Danny

    2014-01-01

    We developed a multiscale particle-based model of platelets, to study the transport dynamics of shear stresses between the surrounding fluid and the platelet membrane. This model facilitates a more accurate prediction of the activation potential of platelets by viscous shear stresses - one of the major mechanisms leading to thrombus formation in cardiovascular diseases and in prosthetic cardiovascular devices. The interface of the model couples coarse-grained molecular dynamics (CGMD) with dissipative particle dynamics (DPD). The CGMD handles individual platelets while the DPD models the macroscopic transport of blood plasma in vessels. A hybrid force field is formulated for establishing a functional interface between the platelet membrane and the surrounding fluid, in which the microstructural changes of platelets may respond to the extracellular viscous shear stresses transferred to them. The interaction between the two systems preserves dynamic properties of the flowing platelets, such as the flipping motion. Using this multiscale particle-based approach, we have further studied the effects of the platelet elastic modulus by comparing the action of the flow-induced shear stresses on rigid and deformable platelet models. The results indicate that neglecting the platelet deformability may overestimate the stress on the platelet membrane, which in turn may lead to erroneous predictions of the platelet activation under viscous shear flow conditions. This particle-based fluid-structure interaction multiscale model offers for the first time a computationally feasible approach for simulating deformable platelets interacting with viscous blood flow, aimed at predicting flow induced platelet activation by using a highly resolved mapping of the stress distribution on the platelet membrane under dynamic flow conditions. PMID:25530818

  6. Effect of Desmopressin on Platelet Aggregation and Blood Loss in Patients Undergoing Valvular Heart Surgery

    OpenAIRE

    Lei Jin; Hong-Wen Ji

    2015-01-01

    Background: Blood loss after cardiac surgery can be caused by impaired platelet (PLT) function after cardiopulmonary bypass. Desmopressin or 1-deamino-8-D-arginine vasopressin (DDAVP) is a synthetic analog of vasopressin. DDAVP can increase the level of von Willebrand factor and coagulation factor VIII, thus it may enhance PLT function and improve coagulation. In this study, we assessed the effects of DDAVP on PLT aggregation and blood loss in patients undergoing cardiac surgery. Methods:...

  7. Blood Disorders - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Blood Disorders URL of this page: https://medlineplus.gov/languages/blooddisorders.html Other topics A-Z A B ...

  8. Expression of myotubularins in blood platelets: Characterization and potential diagnostic of X-linked myotubular myopathy.

    Science.gov (United States)

    Mansour, Rana; Severin, Sonia; Xuereb, Jean-Marie; Gratacap, Marie-Pierre; Laporte, Jocelyn; Buj-Bello, Ana; Tronchère, Hélène; Payrastre, Bernard

    2016-07-29

    Phosphoinositides play a key role in the spatiotemporal control of central intracellular processes and several specific kinases and phosphatases regulating the level of these lipids are implicated in human diseases. Myotubularins are a family of 3-phosphatases acting specifically on phosphatidylinositol 3-monophosphate and phosphatidylinositol 3,5 bisphosphate. Members of this family are mutated in genetic diseases including myotubularin 1 (MTM1) and myotubularin-related protein 2 (MTMR2) which mutations are responsible of X-linked centronuclear myopathy and Charcot-Marie-Tooth neuropathy, respectively. Here we show that MTM1 is expressed in blood platelets and that hundred microliters of blood is sufficient to detect the protein by western blotting. Since the most severe cases of pathogenic mutations of MTM1 lead to loss of expression of the protein, we propose that a minimal amount of blood can allow a rapid diagnostic test of X-linked myotubular myopathy, which is currently based on histopathology of muscle biopsy and molecular genetic testing. In platelets, MTM1 is a highly active 3-phosphatase mainly associated to membranes and found on the dense granules and to a lesser extent on alpha-granules. However, deletion of MTM1 in mouse had no significant effect on platelet count and on platelet secretion and aggregation induced by thrombin or collagen stimulation. Potential compensation by other members of the myotubularin family is conceivable since MTMR2 was easily detectable by western blotting and the mRNA of several members of the family increased during in vitro differentiation of human megakaryocytes and MEG-01 cells. In conclusion, we show the presence of several myotubularins in platelets and propose that minimal amounts of blood can be used to develop a rapid diagnostic test for genetic pathologies linked to loss of expression of these phosphatases. PMID:27155155

  9. Life span and tissue distribution of 111indium-labeled blood platelets in hypomagnesemic lambs

    International Nuclear Information System (INIS)

    Circulating platelets may be activated by exposed triple-helical collagen in atherosclerotic lesions in Mg-deficient ruminants. Autologous platelets, labeled in vitro with 111In and determined to be active, were injected into 5 hypomagnesemic and 3 control lambs fed semipurified diets with 100 or 2,000 mg of Mg/kg of feed for 3 months. During the first 68 hours, 111In concentrations were 11 times higher in packed cells than in plasma. Packed-cell 111In increased 60% during the first 2 hours, probably due to initial tissue sequestration and later release of labeled platelets. Thereafter, platelet half-life span averaged 60 and 63 hours for hypomagnesemic and control lambs. After 68 hours, lambs were injected with native vascular collagen fibrils at 500 micrograms/kg of body weight to initiate reversible platelet aggregation. Within 1 minute, 83% of packed-cell 111In disappeared from circulation. Thirty minutes later, the lambs were euthanatized and necropsied and in the lungs, liver, and spleen, 111In averaged 24%, 19%, and 9%, respectively, of 111In injected 68 hours earlier. Organ deposits were not affected by Mg intake, but 111In in the lungs was somewhat lower in 2 lambs injected with inactivated collagen. Pathologic changes induced by reversible platelet aggregation were compatible with right ventricular failure complicated by pulmonary edema, similar to changes in hypomagnesemic lambs that died spontaneously. Platelets in blood exposed to vascular lesions in hypomagnesemic ruminants could be a major mortality risk factor in grass tetany disease

  10. Diminished adhesion and activation of platelets and neutrophils with CD47-functionalized blood contacting surfaces

    OpenAIRE

    Finley, Matthew J.; Rauova, Lubica; Alferiev, Ivan S.; Weisel, John W.; Levy, Robert J; Stachelek, Stanley J.

    2012-01-01

    CD47 is a ubiquitously expressed transmembrane protein that, through signaling mechanisms mediated by signal regulatory protein alpha (SIRPα1), functions as a biological marker of ‘self-recognition’. We showed previously that inflammatory cell attachment to polymeric surfaces is inhibited by the attachment of biotinylated recombinant CD47 (CD47B). We test herein the hypothesis that CD47-modified blood conduits can reduce platelet and neutrophil activation under clinically relevant conditions....

  11. The effect of oral phenylbutazone on whole blood platelet aggregation in the dog.

    OpenAIRE

    Jackson, M. L.; Searcy, G. P.; Olexson, D W

    1985-01-01

    Platelet aggregation to collagen, arachidonic acid and adenosine diphosphate was evaluated in six dogs using a whole blood electronic aggregometer. The six dogs were then given phenylbutazone orally according to four different dosage levels and durations of treatment. Aggregation responses were measured at established intervals of time following phenylbutazone administration. Data on untreated dogs indicated that arachidonic acid, at a final concentration of 50 micrograms/mL and collagen, at ...

  12. Platelet Component of Hemostasis System and the Content of Homocysteine in Blood Serum in Coxarthrosis

    OpenAIRE

    Fedoseeva I.А.; Ezhov I.Y.; Tcharykova I.N.

    2011-01-01

    The aim of the investigation is to study the content of homocysteine in blood serum and the analysis of thrombocyte aggregation activity in patients suffering from degenerative-dystrophic diseases of coxofemoral joint (coxarthrosis). Materials and Methods. There have been examined 155 patients with coxarthrosis and 45 healthy men and women aged 45—65 years old. The platelet aggregation ability has been studied using adenosine diphosphate (ADP) in small doses (1.25 mkg/ml) and collagen (2....

  13. Variation of Red Blood Cell Distribution Width and Mean Platelet Volume after Moderate Endurance Exercise

    Directory of Open Access Journals (Sweden)

    Giuseppe Lippi

    2014-01-01

    Full Text Available Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217±32 min/week who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC, reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV; mean corpuscular hemoglobin (MCH; reticulocyte haemoglobin content (Ret CHR; RBC distribution width (RDW, mean platelet volume (MPV. No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease.

  14. Variation of red blood cell distribution width and mean platelet volume after moderate endurance exercise.

    Science.gov (United States)

    Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Tarperi, Cantor; Guidi, Gian Cesare; Schena, Federico

    2014-01-01

    Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217 ± 32 min/week) who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC), reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV); mean corpuscular hemoglobin (MCH); reticulocyte haemoglobin content (Ret CHR); RBC distribution width (RDW), mean platelet volume (MPV). No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease. PMID:25197280

  15. Separation of platelets from other blood cells in continuous-flow by dielectrophoresis field-flow-fractionation

    OpenAIRE

    Piacentini, Niccolò; Mernier, Guillaume; Tornay, Raphaël; Renaud, Philippe

    2011-01-01

    We present a microfluidic device capable of separating platelets from other blood cells in continuous flow using dielectrophoresis field-flow-fractionation. The use of hydrodynamic focusing in combination with the application of a dielectrophoretic force allows the separation of platelets from red blood cells due to their size difference. The theoretical cell trajectory has been calculated by numerical simulations of the electrical field and flow speed, and is in agreement with the experiment...

  16. Anti-thrombogenic properties of a nitric oxide-releasing dextran derivative: evaluation of platelet activation and whole blood clotting kinetics

    Science.gov (United States)

    Damodaran, Vinod B.; Leszczak, Victoria; Wold, Kathryn A.; Lantvit, Sarah M.; Popat, Ketul C.; Reynolds, Melissa M.

    2013-01-01

    Controlling platelet activation and clotting initiated by cardiovascular interventions remains a major challenge in clinical practice. In this work, the anti-thrombotic properties of a polysaccharide-based nitric oxide (NO)-releasing dextran derivative are presented. Total platelet adhesion, platelet morphology and whole blood clotting kinetics were used as indicators to evaluate the anti-clotting properties of this material. With a total NO delivery of 0.203±0.003 μmol, the NO-releasing dextran derivative (Dex-SNO) mixed with blood plasma demonstrated a significantly lower amount of platelet adhesion and activation onto a surface and reduced whole blood clotting kinetics. Nearly 75% reduction in platelet adhesion and a significant retention of platelet morphology were observed with blood plasma treated with Dex-SNO, suggesting this to be a potential anti-platelet therapeutic agent for preventing thrombosis that does not have an adverse effect on circulating platelets. PMID:24349705

  17. Platelet [3H]imipramine binding in affective disorders: trait versus state characteristics

    International Nuclear Information System (INIS)

    Platelet [3H]imipramine binding (Bmax) was determined in 67 patients with major affective illness (33 euthymic bipolar, 34 depressed unipolar) and 58 normal control subjects. Bipolar patients had significantly lower Bmax values than did control subjects. The mean Bmax in the unipolar patients was lower than in the control subjects, but the difference was not statistically significant. Dissociation constant (Kd) values did not distinguish patients in either category from control subjects. The significantly lower Bmax in euthymic bipolar patients and the apparent state independence of Bmax in some but not all unipolar patients suggest that platelet imipramine binding may be a trait marker in a subset of affective disorders

  18. The miRNA Profile of Platelets Stored in a Blood Bank and Its Relation to Cellular Damage from Storage

    OpenAIRE

    Pontes, Thaís Brilhante; Moreira-Nunes, Caroline de Fátima Aquino; Maués, Jersey Heitor da Silva; Lamarão, Letícia Martins; de Lemos, José Alexandre Rodrigues; Montenegro, Raquel Carvalho; Burbano, Rommel Mário Rodriguez

    2015-01-01

    Millions of blood products are transfused each year, and many lives are directly affected by transfusion. Platelet concentrate (PC) is one of the main products derived from blood. Even under good storage conditions, PC is likely to suffer cell damage. The shape of platelets changes after 5 to 7 days of storage at 22°C. Taking into consideration that some platelet proteins undergo changes in their shape and functionality during PC storage. Sixteen PC bags were collected and each PC bag tube wa...

  19. Serotonin binding in vitro by releasable proteins from human blood platelets

    International Nuclear Information System (INIS)

    Among the substances released from human blood platelets are serotonin and various proteins. It was hypothesized that one of these proteins binds serotonin and that serotonin might be important to the protein's function or that the protein might be important to serotonin's function. Two platelet-specific proteins, platelet factor 4 (PF4) and β-thromboglobulin (βTG) were found to bind serotonin in vitro. Endogenous PF4 was isolated by serotonin-affinity chromatography and was identified by radioimmunoassay. Purified [125I] -PF4 and native PF4 bound to and eluted from a serotonin-affinity column similarly. Ultrafiltration of the homologous protein, βTG, with [14C]-serotonin demonstrated binding of about 8 moles serotonin per mole tetrameric βTG with a dissociation constant of about 4 X 10(sup-8) M. Equilibrium dialysis of PF4 with radiolabelled serotonin was attempted, but no binding constant values were obtained because serotonin apparently bound to the dialysis membrane. Since EDTA was one of the two agents that eluted PF4 from the serotonin-affinity gel, calcium binding by PF4 was investigated by equilibrium dialysis. Evidence was obtained for positively cooperative binding of calcium ions by PF4. It is concluded that PF4 and βTG bind serotonin in vitro, that they may also bind in vivo when platelets undergo release, and that the functions of serotonin, PF4 and βTG may be mediated in part by serotonin-protein associations

  20. Characterization of the effects of isoprostanes on platelet aggregation in human whole blood

    OpenAIRE

    Cranshaw, Julius H; Evans, Timothy W.; Mitchell, Jane A.

    2001-01-01

    We tested the effects of 11 commercially-available isoprostanes on platelet aggregation directly or when triggered by the thromboxane receptor agonist U46619 or collagen in healthy human citrated blood using a whole blood aggregometer.None of the isoprostanes tested triggered aggregation alone, nor facilitated aggregation by a sub-threshold dose of U46619 or collagen. Five isoprostanes inhibited aggregation (rank order of potency 8-iso PGE1>8-iso PGE2>8-iso PGF2α>8-iso PGF3α>8-iso-13,14-dihyd...

  1. Platelet serotonin levels in pervasive developmental disorders and mental retardation : Diagnostic group differences, within-group distribution, and behavioral correlates

    NARCIS (Netherlands)

    Mulder, EJ; Anderson, GM; Kema, IP; de Bildt, A; van Lang, NDJ; den Boer, JA; Minderaa, RB

    2004-01-01

    Objective: To investigate group differences, the within-group distributions, and the clinical correlates of platelet serotonin (5-HT) levels in pervasive developmental disorders (PDD). Method: Platelet 5-HT levels were measured in Dutch children and young adults, recruited from 2001 through 2003, wi

  2. Defective platelet aggregation to the calcium ionophore A23187 in a patient with a lifelong bleeding disorder.

    OpenAIRE

    Machin, S J; Keenan, J. P.; McVerry, B A

    1983-01-01

    A patient with a lifelong bleeding disorder is presented with a prolonged bleeding time and abnormal aggregation and secretion responses to arachidonic acid, thromboxane A2, PAF-acether and the divalent calcium ionophore A23187. Platelet alpha and dense granule contents and morphology appear normal. The proposed defect is due to an abnormality of a platelet intracellular calcium dependent process.

  3. Platelet Serotonin Levels in Pervasive Developmental Disorders and Mental Retardation: Diagnostic Group Differences, Within-Group Distribution, and Behavioral Correlates.

    Science.gov (United States)

    Mulder, Erik J.; Anderson, George M.; Kema, Ido P.; De Bildt, Annelies; Van Lang, Natasja D.J.; Den Boer, Johan A.; Minderaa Ruud B.

    2004-01-01

    Objective: To investigate group differences, the within-group distributions, and the clinical correlates of platelet serotonin (5-HT) levels in pervasive developmental disorders (PDD). Method: Platelet 5-HT levels were measured in Dutch children and young adults, recruited from 2001 through 2003, with PDD (autism, Asperger's and PDD-not otherwise…

  4. A multiple time stepping algorithm for efficient multiscale modeling of platelets flowing in blood plasma

    Science.gov (United States)

    Zhang, Peng; Zhang, Na; Deng, Yuefan; Bluestein, Danny

    2015-03-01

    We developed a multiple time-stepping (MTS) algorithm for multiscale modeling of the dynamics of platelets flowing in viscous blood plasma. This MTS algorithm improves considerably the computational efficiency without significant loss of accuracy. This study of the dynamic properties of flowing platelets employs a combination of the dissipative particle dynamics (DPD) and the coarse-grained molecular dynamics (CGMD) methods to describe the dynamic microstructures of deformable platelets in response to extracellular flow-induced stresses. The disparate spatial scales between the two methods are handled by a hybrid force field interface. However, the disparity in temporal scales between the DPD and CGMD that requires time stepping at microseconds and nanoseconds respectively, represents a computational challenge that may become prohibitive. Classical MTS algorithms manage to improve computing efficiency by multi-stepping within DPD or CGMD for up to one order of magnitude of scale differential. In order to handle 3-4 orders of magnitude disparity in the temporal scales between DPD and CGMD, we introduce a new MTS scheme hybridizing DPD and CGMD by utilizing four different time stepping sizes. We advance the fluid system at the largest time step, the fluid-platelet interface at a middle timestep size, and the nonbonded and bonded potentials of the platelet structural system at two smallest timestep sizes. Additionally, we introduce parameters to study the relationship of accuracy versus computational complexities. The numerical experiments demonstrated 3000x reduction in computing time over standard MTS methods for solving the multiscale model. This MTS algorithm establishes a computationally feasible approach for solving a particle-based system at multiple scales for performing efficient multiscale simulations.

  5. A Multiple Time Stepping Algorithm for Efficient Multiscale Modeling of Platelets Flowing in Blood Plasma

    Science.gov (United States)

    Zhang, Peng; Zhang, Na; Deng, Yuefan; Bluestein, Danny

    2015-01-01

    We developed a multiple time-stepping (MTS) algorithm for multiscale modeling of the dynamics of platelets flowing in viscous blood plasma. This MTS algorithm improves considerably the computational efficiency without significant loss of accuracy. This study of the dynamic properties of flowing platelets employs a combination of the dissipative particle dynamics (DPD) and the coarse-grained molecular dynamics (CGMD) methods to describe the dynamic microstructures of deformable platelets in response to extracellular flow-induced stresses. The disparate spatial scales between the two methods are handled by a hybrid force field interface. However, the disparity in temporal scales between the DPD and CGMD that requires time stepping at microseconds and nanoseconds respectively, represents a computational challenge that may become prohibitive. Classical MTS algorithms manage to improve computing efficiency by multi-stepping within DPD or CGMD for up to one order of magnitude of scale differential. In order to handle 3–4 orders of magnitude disparity in the temporal scales between DPD and CGMD, we introduce a new MTS scheme hybridizing DPD and CGMD by utilizing four different time stepping sizes. We advance the fluid system at the largest time step, the fluid-platelet interface at a middle timestep size, and the nonbonded and bonded potentials of the platelet structural system at two smallest timestep sizes. Additionally, we introduce parameters to study the relationship of accuracy versus computational complexities. The numerical experiments demonstrated 3000x reduction in computing time over standard MTS methods for solving the multiscale model. This MTS algorithm establishes a computationally feasible approach for solving a particle-based system at multiple scales for performing efficient multiscale simulations. PMID:25641983

  6. Platelet alpha 2-adrenergic receptors in major depressive disorder. Binding of tritiated clonidine before and after tricyclic antidepressant drug treatment

    International Nuclear Information System (INIS)

    The specific binding of tritiated (3H)-clonidine, an alpha 2-adrenergic receptor agonist, to platelet membranes was measured in normal subjects and in patients with major depressive disorder. The number of platelet alpha 2-adrenergic receptors from the depressed group was significantly higher than that found in platelets obtained from the control population. Treatment with tricyclic antidepressant drugs led to significant decreases in the number of platelet alpha 2-adrenergic receptors. These results support the hypothesis that the depressive syndrome is related to an alpha 2-adrenergic receptor supersensitivity and that the clinical effectiveness of tricyclic antidepressant drugs is associated with a decrease in the number of these receptors

  7. Platelet gene therapy improves hemostatic function for integrin αIIbβ3-deficient dogs

    OpenAIRE

    Fang, Juan; Jensen, Eric S; Boudreaux, Mary K.; Du, Lily M.; Hawkins, Troy B.; Koukouritaki, Sevasti B.; Cornetta, Kenneth; Wilcox, David A.

    2011-01-01

    Activated blood platelets mediate the primary response to vascular injury. Although molecular abnormalities of platelet proteins occur infrequently, taken collectively, an inherited platelet defect accounts for a bleeding diathesis in ≈1:20,000 individuals. One rare example of a platelet disorder, Glanzmann thrombasthenia (GT), is characterized by life-long morbidity and mortality due to molecular abnormalities in a major platelet adhesion receptor, integrin αIIbβ3. Transfusion therapy is fre...

  8. In Vitro impairment of whole blood coagulation and platelet function by hypertonic saline hydroxyethyl starch

    Directory of Open Access Journals (Sweden)

    Görlinger Klaus

    2011-02-01

    Full Text Available Abstract Background Hypertonic saline hydroxyethyl starch (HH has been recommended for first line treatment of hemorrhagic shock. Its effects on coagulation are unclear. We studied in vitro effects of HH dilution on whole blood coagulation and platelet function. Furthermore 7.2% hypertonic saline, 6% hydroxyethylstarch (as ingredients of HH, and 0.9% saline solution (as control were tested in comparable dilutions to estimate specific component effects of HH on coagulation. Methods The study was designed as experimental non-randomized comparative in vitro study. Following institutional review board approval and informed consent blood samples were taken from 10 healthy volunteers and diluted in vitro with either HH (HyperHaes®, Fresenius Kabi, Germany, hypertonic saline (HT, 7.2% NaCl, hydroxyethylstarch (HS, HAES6%, Fresenius Kabi, Germany or NaCl 0.9% (ISO in a proportion of 5%, 10%, 20% and 40%. Coagulation was studied in whole blood by rotation thrombelastometry (ROTEM after thromboplastin activation without (ExTEM and with inhibition of thrombocyte function by cytochalasin D (FibTEM, the latter was performed to determine fibrin polymerisation alone. Values are expressed as maximal clot firmness (MCF, [mm] and clotting time (CT, [s]. Platelet aggregation was determined by impedance aggregrometry (Multiplate after activation with thrombin receptor-activating peptide 6 (TRAP and quantified by the area under the aggregation curve (AUC [aggregation units (AU/min]. Scanning electron microscopy was performed to evaluate HyperHaes induced cell shape changes of thrombocytes. Statistics: 2-way ANOVA for repeated measurements, Bonferroni post hoc test, p Results Dilution impaired whole blood coagulation and thrombocyte aggregation in all dilutions in a dose dependent fashion. In contrast to dilution with ISO and HS, respectively, dilution with HH as well as HT almost abolished coagulation (MCFExTEM from 57.3 ± 4.9 mm (native to 1.7 ± 2.2 mm (HH 40

  9. Platelet kinetics

    International Nuclear Information System (INIS)

    Recently, the in vivo processes of platelet function and the reaction and interaction of platelets with components of the blood vessel wall and artificial surfaces have received increasing attention. In this article the focus is placed on two aspects of platelet function and kinetics as revealed by 111In-labelled platelets. First the interaction of platelets with foreign prosthetic surfaces is discussed and some interesting facets of platelet functions that have come to light, are pointed out. Secondly, experiences with the development and refinement of an improved technique, namely the dual-isotope subtraction method, which increases the sensitivity of platelet imaging and allows the detection of relatively small areas of platelet deposition with accuracy, are described

  10. Methods for defining distinct bioenergetic profiles in platelets, lymphocytes, monocytes, and neutrophils, and the oxidative burst from human blood

    OpenAIRE

    Chacko, Balu K; Kramer, Philip A.; Ravi, Saranya; Johnson, Michelle S.; Hardy, Robert W.; Ballinger, Scott W.; Darley-Usmar, Victor M.

    2013-01-01

    Peripheral blood mononuclear cells and platelets have long been recognized as having the potential to act as sensitive markers for mitochondrial dysfunction in a broad range of pathological conditions. However, the bioenergetic function of these cells has not been examined from the same donors, yet this is important for the selection of cell types for translational studies. Here, we demonstrate the measurement of cellular bioenergetics in isolated human monocytes, lymphocytes, and platelets, ...

  11. COX-2 Inhibition by Use of Rofecoxib or High Dose Aspirin Enhances ADP-Induced Platelet Aggregation in Fresh Blood

    OpenAIRE

    Borgdorff, P.; Handoko, M.L.; Wong, Y.Y.; Tangelder, G.J.

    2010-01-01

    Aim: Increased cardiovascular risk after use of selective or nonselective cyclooxygenase-2 (COX-2)-inhibitors might partly be caused by enhanced platelet aggregability. However, an effect of COX-2 inhibition on platelets has so far not been observed in humans. Methods: We tested in healthy volunteers the effect of COX-2-inhibition nearly in-vivo, i.e. immediately after and even during blood sampling. Results: Measurement within 2 minutes after venipuncture, but not 60 minutes later, showed th...

  12. Decreased uptake of 3H-serotonin and endogenous content of serotonin in blood platelets in hypertensive patients

    International Nuclear Information System (INIS)

    The uptake and content of serotonin in blood platelets were studied in patients with essential hypertension and in five families in which at least one member was hypertensive. Blood was obtained from male and female normotensive volunteers and hypertensive patients who were free of medication. Lineweaver-Burk plots of 3H-serotonin uptake from both control subjects and hypertensive patients were linear, which suggested simple Michaelis-Menten uptake kinetics. The maximal uptake velocity (Vmax) in hypertensive patients was significantly lower than in control subjects (control . 41.7 +/- 3.3 pmol/min/10(8) platelets, n . 17; hypertensive . 26.6 +/- 3.0 pmol/min/10(8) platelets, n . 16; p less than 0.005). The affinity constant (Km) was slightly but significantly lower in hypertensive patients (control . 0.70 +/- 0.08 microM; hypertensive . 0.46 +/- 0.08 microM; p less than 0.05). The serotonin content in blood platelets determined by high pressure liquid chromatography with electrochemical detection was significantly lower in hypertensive patients (control . 165.0 +/- 12.9 nmol/10(11) platelets, n . 29; hypertensive . 105.9 +/- 10.4 nmol/10(11) platelets, n . 27; p less than 0.001). In the five families investigated, the lowered serotonin content was observed in some normotensive members. The reduced number of carriers of serotonin uptake and the slight decrease in the affinity constant observed in platelets of patients with essential hypertension suggest that serotonin metabolism is altered in essential hypertension and that blood platelets may be a useful model in studying the serotonergic modifications at the molecular level

  13. Bleeding Disorders

    Science.gov (United States)

    ... times I'd miss work and skip the gym because I felt so lousy. So I decided ... cell called platelets. Your body also needs blood proteins called clotting factors. In people with bleeding disorders, ...

  14. In-line filtration of platelet concentrates obtained with the Omnix blood cell separator.

    Science.gov (United States)

    Moog, R; Müller, N; Nieper, A

    1995-12-01

    The quality of platelet concentrates (PC) obtained with the blood cell separator Omnix was investigated before and after in-line filtration. PC were filtered 2h (protocol A) and 4 h (protocol B) after the termination of apheresis. Platelet (PLT) yield after filtration was similar in both protocols (median 3.7 vs. 3.4 x 10(11)). Median white blood cell (WBC) contamination after leucocyte depletion was 0.07 x 10(6) (range 0.02-3.27 x 10(6)) in protocol A and 0.06 x 10(6) (range 0.02-2.1 x 10(6)) in protocol B. Glucose, lactate, lactate dehydrogenase, morphology score and pH value were not statistically different before and after filtration in both protocols. We conclude that in-line filtration results in sufficient leucocyte depletion of the PC. The prefiltration storage time did not influence the studied parameters of product quality. PMID:8646295

  15. In vitro interactions of blood, platelet, and fibroblast with biodegradable magnesium-zinc-strontium alloys.

    Science.gov (United States)

    Nguyen, T Y; Cipriano, A F; Guan, Ren-Guo; Zhao, Zhan-Yong; Liu, Huinan

    2015-09-01

    Magnesium (Mg) alloy is an attractive class of metallic biomaterial for cardiovascular applications due to its biodegradability and mechanical properties. In this study, we investigated the degradation in blood, thrombogenicity, and cytocompatibility of Magnesium-Zinc-Strontium (Mg-Zn-Sr) alloys, specifically four Mg-4 wt % Zn-xSr (x = 0.15, 0.5, 1, and 1.5 wt %) alloys, together with pure Mg control and relevant reference materials for cardiovascular applications. Human whole blood and platelet rich plasma (PRP) were used as the incubation media to investigate the degradation behavior of the Mg-Zn-Sr alloys. The results showed that the PRP had a greater pH increase and greater concentration of Mg(2+) ions when compared with whole blood after 2 h of incubation with the same respective Mg alloys, suggesting that the Mg alloys degraded faster in PRP than in whole blood. The Mg alloy with 4 wt % Zn and 0.15 wt % Sr (named as ZSr41A) was identified as the most promising alloy for cardiovascular stent applications, because it showed slower degradation and less thrombogenicity, as indicated by the lower concentrations of Mg(2+) ions released and less deposition of platelets. Additionally, ZSr41 alloys were cytocompatible with fibroblasts in direct exposure culture in which the cells adhered and proliferated around the samples, with no statistical difference in cell adhesion density compared with the blank reference. Future studies on the ZSr41 alloys are necessary to investigate their direct interactions with other important cells in cardiovascular system, such as vascular endothelial cells and smooth muscle cells. PMID:25690931

  16. Studies on antioxidant properties of polyphenol-rich extract from berries of Aronia melanocarpa in blood platelets.

    Science.gov (United States)

    Olas, B; Wachowicz, B; Nowak, P; Kedzierska, M; Tomczak, A; Stochmal, A; Oleszek, W; Jeziorski, A; Piekarski, J

    2008-12-01

    The antioxidant properties of extract from berries of Aronia melanocarpa (chokeberry) containing: anthocyanidines, phenolic acids and quercetine glycosides on oxidative/nitrative stress induced by peroxynitrite (ONOO(-), a powerful physiological oxidant, nitrating species and inflammatory mediator) in human blood platelets were studied in vitro. The extract from A. melanocarpa (5 - 50 microg/mL) significantly inhibited platelet protein carbonylation (measured by ELISA method) and thiol oxidation estimated with 5,5'-dithio-bis(2-nitro-benzoic acid) (DTNB) induced by peroxynitrite (0.1 mM) (IC(50)--35 microg/mL for protein carbonylation, and IC(50)--33 microg/mL for protein thiol oxidation). The tested extract only slightly reduced platelet protein nitration (measured by C- ELISA method). The extract also caused a distinct reduction of platelet lipid peroxidation induced by peroxynitrite. Moreover, in our preliminary experiments we observed that the extract (50 microg/mL) reduced oxidative/nitrative stress in blood platelets from patients with breast cancer. The obtained results indicate that in vitro the extract from A. melanocarpa has the protective effects against peroxynitrite-induced oxidative/nitrative damage to the human platelet proteins and lipids. The extract from A. melanocarpa seems to be also useful as an antioxidant in patients with breast cancer. PMID:19212014

  17. Alkali treatment of microrough titanium surfaces affects macrophage/monocyte adhesion, platelet activation and architecture of blood clot formation

    Directory of Open Access Journals (Sweden)

    V Milleret

    2011-05-01

    Full Text Available Titanium implants are most commonly used for bone augmentation and replacement due to their favorable osseointegration properties. Here, hyperhydrophilic sand-blasted and acid-etched (SBA titanium surfaces were produced by alkali treatment and their responses to partially heparinized whole human blood were analyzed. Blood clot formation, platelet activation and activation of the complement system was analyzed revealing that exposure time between blood and the material surface is crucial as increasing exposure time results in higher amount of activated platelets, more blood clots formed and stronger complement activation. In contrast, the number of macrophages/monocytes found on alkali-treated surfaces was significantly reduced as compared to untreated SBA Ti surfaces. Interestingly, when comparing untreated to modified SBA Ti surfaces very different blood clots formed on their surfaces. On untreated Ti surfaces blood clots remain thin (below 15 mm, patchy and non-structured lacking large fibrin fiber networks whereas blood clots on differentiated surfaces assemble in an organized and layered architecture of more than 30 mm thickness. Close to the material surface most nucleated cells adhere, above large amounts of non-nucleated platelets remain entrapped within a dense fibrin fiber network providing a continuous cover of the entire surface. These findings might indicate that, combined with findings of previous in vivo studies demonstrating that alkali-treated SBA Ti surfaces perform better in terms of osseointegration, a continuous and structured layer of blood components on the blood-facing surface supports later tissue integration of an endosseous implant.

  18. Platelet function tests: a comparative review

    Directory of Open Access Journals (Sweden)

    Paniccia R

    2015-02-01

    Full Text Available Rita Paniccia,1,2 Raffaella Priora,1,2 Agatina Alessandrello Liotta,2 Rosanna Abbate1,2 1Department of Experimental and Clinical Medicine, Thrombosis Center, University of Florence, Florence, Italy; 2Department of Heart and Vessels, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy Abstract: In physiological hemostasis a prompt recruitment of platelets on the vessel damage prevents the bleeding by the rapid formation of a platelet plug. Qualitative and/or quantitative platelet defects promote bleeding, whereas the high residual reactivity of platelets in patients on antiplatelet therapies moves forward thromboembolic complications. The biochemical mechanisms of the different phases of platelet activation – adhesion, shape change, release reaction, and aggregation – have been well delineated, whereas their complete translation into laboratory assays has not been so fulfilled. Laboratory tests of platelet function, such as bleeding time, light transmission platelet aggregation, lumiaggregometry, impedance aggregometry on whole blood, and platelet activation investigated by flow cytometry, are traditionally utilized for diagnosing hemostatic disorders and managing patients with platelet and hemostatic defects, but their use is still limited to specialized laboratories. To date, a point-of-care testing (POCT dedicated to platelet function, using pertinent devices much simpler to use, has now become available (ie, PFA-100, VerifyNow System, Multiplate Electrode Aggregometry [MEA]. POCT includes new methodologies which may be used in critical clinical settings and also in general laboratories because they are rapid and easy to use, employing whole blood without the necessity of sample processing. Actually, these different platelet methodologies for the evaluation of inherited and acquired bleeding disorders and/or for monitoring antiplatelet therapies are spreading and the study of platelet function is strengthening. In this review, well

  19. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation

    OpenAIRE

    Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

    2013-01-01

    The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-depende...

  20. Efficient removal of platelets from peripheral blood progenitor cell products using a novel micro-chip based acoustophoretic platform.

    Directory of Open Access Journals (Sweden)

    Josefina Dykes

    Full Text Available BACKGROUND: Excessive collection of platelets is an unwanted side effect in current centrifugation-based peripheral blood progenitor cell (PBPC apheresis. We investigated a novel microchip-based acoustophoresis technique, utilizing ultrasonic standing wave forces for the removal of platelets from PBPC products. By applying an acoustic standing wave field onto a continuously flowing cell suspension in a micro channel, cells can be separated from the surrounding media depending on their physical properties. STUDY DESIGN AND METHODS: PBPC samples were obtained from patients (n = 15 and healthy donors (n = 6 and sorted on an acoustophoresis-chip. The acoustic force was set to separate leukocytes from platelets into a target fraction and a waste fraction, respectively. The PBPC samples, the target and the waste fractions were analysed for cell recovery, purity and functionality. RESULTS: The median separation efficiency of leukocytes to the target fraction was 98% whereas platelets were effectively depleted by 89%. PBPC samples and corresponding target fractions were similar in the percentage of CD34+ hematopoetic progenitor/stem cells as well as leukocyte/lymphocyte subset distributions. Median viability was 98%, 98% and 97% in the PBPC samples, the target and the waste fractions, respectively. Results from hematopoietic progenitor cell assays indicated a preserved colony-forming ability post-sorting. Evaluation of platelet activation by P-selectin (CD62P expression revealed a significant increase of CD62P+ platelets in the target (19% and waste fractions (20%, respectively, compared to the PBPC input samples (9%. However, activation was lower when compared to stored blood bank platelet concentrates (48%. CONCLUSION: Acoustophoresis can be utilized to efficiently deplete PBPC samples of platelets, whilst preserving the target stem/progenitor cell and leukocyte cell populations, cell viability and progenitor cell colony-forming ability

  1. Influence of mental stress on platelet bioactivity

    OpenAIRE

    Koudouovoh-Tripp, Pia; Sperner-Unterweger, Barbara

    2012-01-01

    It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to represent a possible link in this respect. The anculeated platelets are the smallest corpuscular elements circulating in the human blood. They display different serotonergic markers which seem to reflect the central nervous serotonin metabolism. They are known as main effectors ...

  2. Determination of vascular endothelial growth factor (VEGF) in circulating blood: significance of VEGF in various leucocytes and platelets

    DEFF Research Database (Denmark)

    Werther, K; Christensen, Ib Jarle; Nielsen, Hans Jørgen

    2002-01-01

    contained considerable amounts of VEGF. In isolated lymphocytes and monocytes, VEGF was not present in measurable amounts. The number of neutrophils was significantly (p<0.0001) correlated to VEGF concentrations in lysed whole blood, but not to VEGF concentrations in plasma or serum. The number of platelets...... clotting. CONCLUSION: Circulating neutrophils contain considerable amounts of VEGF that contribute to high VEGF levels in lysed whole blood. VEGF in circulating platelets contributes to high VEGF levels in serum and lysed whole blood. Allowing whole blood samples to clot for between 2 and 6 h before serum......AIM: The sources of increased vascular endothelial growth factor (VEGF) concentrations in peripheral blood from cancer patients are not known in detail. The aim of the present study was to evaluate correlations between the VEGF content in isolated leucocyte subpopulations and VEGF concentrations in...

  3. Effects of garcinol and guttiferone K isolated from Garcinia cambogia on oxidative/nitrative modifications in blood platelets and plasma.

    Science.gov (United States)

    Kolodziejczyk, Joanna; Masullo, Milena; Olas, Beata; Piacente, Sonia; Wachowicz, Barbara

    2009-11-01

    The effects of garcinol and guttiferone K, two polyisoprenylated benzophenones occurring a food plant called Garcinia cambogia, on oxidative/nitrative protein damage (determined by parameters such as levels of protein carbonyl groups and nitrotyrosine residues) in human blood platelets and plasma after treatment with peroxynitrite (ONOO(-)) were studied in vitro. We also investigated the effects of garcinol and guttiferone K on lipid peroxidation in blood platelets and plasma induced by ONOO(-) (100 microM). Exposure of blood platelets or plasma to peroxynitrite (100 microM) resulted in an increased level of carbonyl groups and nitrotyrosine residues in proteins, and an increase of lipid peroxidation measured by the level of thiobarbituric acid reactive species (TBARS). In the presence of garcinol and guttiferone K (0.1-25 microg/ml), a distinct reduction in the formation of carbonyl groups in plasma and platelet proteins together with the decrease of TBARS caused by 100 microM peroxynitrite, was observed. However, garcinol and guttiferone K did not inhibit plasma and platelet protein nitration induced by peroxynitrite. Polyisoprenylated benzophenones present in human diet such as garcinol or guttiferone K in vitro have protective effects against lipid and protein oxidation and may have some promising effects in vivo because they are good antioxidants in the tested models in vitro. Garcinol and guttiferone K can be also useful as protecting factors against diseases associated with oxidative stress. PMID:19852687

  4. Rearranged EML4-ALK fusion transcripts sequester in circulating blood platelets and enable blood-based crizotinib response monitoring in non-small-cell lung cancer

    Science.gov (United States)

    Nilsson, R. Jonas A.; Karachaliou, Niki; Berenguer, Jordi; Gimenez-Capitan, Ana; Schellen, Pepijn; Teixido, Cristina; Tannous, Jihane; Kuiper, Justine L.; Drees, Esther; Grabowska, Magda; van Keulen, Marte; Heideman, Danielle A.M.; Thunnissen, Erik; Dingemans, Anne-Marie C.; Viteri, Santiago; Tannous, Bakhos A.; Drozdowskyj, Ana; Rosell, Rafael; Smit, Egbert F.; Wurdinger, Thomas

    2016-01-01

    Purpose: Non-small-cell lung cancers harboring EML4-ALK rearrangements are sensitive to crizotinib. However, despite initial response, most patients will eventually relapse, and monitoring EML4-ALK rearrangements over the course of treatment may help identify these patients. However, challenges associated with serial tumor biopsies have highlighted the need for blood-based assays for the monitoring of biomarkers. Platelets can sequester RNA released by tumor cells and are thus an attractive source for the non-invasive assessment of biomarkers. Methods: EML4-ALK rearrangements were analyzed by RT-PCR in platelets and plasma isolated from blood obtained from 77 patients with non-small-cell lung cancer, 38 of whom had EML4-ALK-rearranged tumors. In a subset of 29 patients with EML4-ALK-rearranged tumors who were treated with crizotinib, EML4-ALK rearrangements in platelets were correlated with progression-free and overall survival. Results: RT-PCR demonstrated 65% sensitivity and 100% specificity for the detection of EML4-ALK rearrangements in platelets. In the subset of 29 patients treated with crizotinib, progression-free survival was 3.7 months for patients with EML4-ALK+ platelets and 16 months for those with EML4-ALK− platelets (hazard ratio, 3.5; P = 0.02). Monitoring of EML4-ALK rearrangements in the platelets of one patient over a period of 30 months revealed crizotinib resistance two months prior to radiographic disease progression. Conclusions: Platelets are a valuable source for the non-invasive detection of EML4-ALK rearrangements and may prove useful for predicting and monitoring outcome to crizotinib, thereby improving clinical decisions based on radiographic imaging alone. PMID:26544515

  5. Inhibition of human platelet aggregation by a novel S-nitrosothiol is abolished by haemoglobin and red blood cells in vitro: implications for anti-thrombotic therapy

    OpenAIRE

    Megson, Ian L; Sogo, Naoki; Mazzei, Francesca A; Butler, Anthony R.; Walton, John C; Webb, David J.

    2000-01-01

    S-Nitrosothiols are nitric oxide (NO) donor drugs that have been shown to inhibit platelet aggregation in platelet rich plasma (PRP) in vitro and to inhibit platelet activation in vivo. The aim of this study was to compare the platelet effects of a novel S-nitrosated glyco-amino acid, RIG200, with an established S-nitrosothiol, S-nitrosoglutathione (GSNO) in PRP, and to investigate the effects of cell-free haemoglobin and red blood cells on S-nitrosothiol-mediated inhibition of platelet aggre...

  6. A comparative evaluation of the blood clot, platelet-rich plasma, and platelet-rich fibrin in regeneration of necrotic immature permanent teeth: A clinical study

    Directory of Open Access Journals (Sweden)

    Isha Narang

    2015-01-01

    Full Text Available Introduction: This study was designed as a clinical trial to evaluate and compare the regenerative potential of platelet-rich fibrin (PRF, platelet-rich plasma (PRP, and blood clot in immature necrotic permanent teeth with or without associated apical periodontitis. Methods: Access preparation was done under rubber dam isolation. Copious irrigation was done with 2.5% NaOCl and triple antibiotic paste was placed as an intracanal medicament. After 4 weeks, the cases were divided into four groups with five patients in each group. The study design had three test arms and one control arm. Group I in which mineral trioxide aggregate apexification was carried out and it was kept as control group to evaluate the regenerative potential of blood clot and platelet concentrates, Group II in which blood clot was used as scaffold in the canal, Group III in PRF was used as scaffold, and Group IV in which PRP carried on collagen was used as a scaffold. Results: The clinical and radiographic evaluation after 6 and 18 months was done by two independent observers who were blinded from the groups. The scoring was done as: None score was denoted by, Fair by 1, Good by 2, and Excellent by 3. The data were then analyzed statistically by Fisher′s exact test using Statistics and Data 11.1(PRP Using harvest Smart PReP2 which showed statistically significant values in Group III as compared to other Groups. Conclusion: PRF has huge potential to accelerate the growth characteristics in immature necrotic permanent teeth as compared to PRP and blood clot.

  7. Partial Purification of the 5-Hydroxytryptamine-Reuptake System from Human Blood Platelets Using a Citalopram-Derived Affinity Resin

    NARCIS (Netherlands)

    Biessen, E.A.L.; Horn, A.S.; Robillard, G.T.

    1990-01-01

    This paper describes a procedure for the synthesis and application of a citalopram-derived affinity resin in purifying the 5HT-reuptake system from human blood platelets. A two-step scheme has been developed for partial purification, based on wheat germ agglutinin-lectin (WGA) affinity and citalopra

  8. What Should You Know about Blood Disorders in Women?

    Science.gov (United States)

    ... Although there are no cures for bleeding disorders, treatment is available to control symptoms and help women avoid complications and invasive procedures. Related Links Deep Vein Thrombosis Hemophilia Von Willebrand Disease Blood Disorders Home A- ...

  9. Platelet Count

    Science.gov (United States)

    ... or exertion Recovery from excess alcohol consumption and vitamin B12 and folate deficiency Rarely, thrombocytosis is caused by ... have bleeding problems, as the platelets may not function normally. This disorder is often associated with a ...

  10. Assessment of the influence of the inflammatory process on the activation of blood platelets and morphological parameters in patients with ulcerative colitis (colitis ulcerosa

    Directory of Open Access Journals (Sweden)

    Beata Polińska

    2011-04-01

    Full Text Available Ulcerative colitis (colitis ulcerosa is a non-specific inflammatory bowel disease of unknown etiology. Thesymptoms which are observed in the course of ulcerative colitis are: an increase in the number of leukocytes andblood platelets, an increase in the concentration of IL-6 and anemia. Blood platelets are the key element, linkingthe processes of hemostasis, inflammation and the repair of damaged tissues. Activation of blood platelets is connectedwith changes in their shape and the occurrence of the reaction of release. P-selectin appears on the surfacesof activated blood platelets and the concentration level of soluble P-selectin increases in the blood plasma. The aimof this study was to define whether the increased number of blood platelets in patients with ulcerative colitisaccompanies changes in their activation and morphology. A total of 16 subjects with ulcerative colitis and 32healthy subjects were studied. Mean platelet count, morphological parameters of platelets and MPC were measuredusing an ADVIA 120 hematology analyzer. Concentrations of sP-selectin and IL-6 in serum were marked byimmunoassay (ELISA. MPC, concentration of sP-selectin and IL-6 were significantly higher in subjects with ulcerativecolitis compared to those in the healthy group. There was a decrease of MPV in patients with ulcerativecolitis, which is statistically significant. Chronic inflammation in patients with ulcerative colitis causes an increase inthe number of blood platelets, a change in their morphology and activation. Decreased MPV value reflects activationand the role blood platelets play in the inflammatory process of the mucous membrane of the colon. A highconcentration of sP-selectin, which is a marker of blood platelet activation, demonstrates their part in the inflammatoryprocess. The increase in the concentration of sP-selectin correlated positively with the increase in concentrationof IL-6. This is why it may be a useful marker of the activity of

  11. New analogues of 13-hydroxyocatdecadienoic acid and 12-hydroxyeicosatetraenoic acid block human blood platelet aggregation and cyclooxygenase-1 activity

    Directory of Open Access Journals (Sweden)

    Hirz Taghreed

    2012-12-01

    Full Text Available Abstract Background Thromboxane A2 is derived from arachidonic acid through the action of cyclooxygenases and thromboxane synthase. It is mainly formed in blood platelets upon activation and plays an important role in aggregation. Aspirin is effective in reducing the incidence of complications following acute coronary syndrome and stroke. The anti-thrombotic effect of aspirin is obtained through the irreversible inhibition of cyclooxygenases. Analogues of 12-hydroxyeicosatetraenoic acid and 13-hydroxyocatdecadienoic acid were shown previously to modulate platelet activation and to block thromboxane receptors. Results and discussion We synthesized 10 compounds based on the structures of analogues of 12-hydroxyeicosatetraenoic acid and 13-hydroxyocatdecadienoic acid and evaluated their effect on platelet aggregation triggered by arachidonic acid. The structure activity relationship was evaluated. Five compounds showed a significant inhibition of platelet aggregation and highlighted the importance of the lipidic hydrophobic hydrocarbon chain and the phenol group. Their IC50 ranged from 7.5 ± 0.8 to 14.2 ± 5.7 μM (Mean ± S.E.M.. All five compounds decreased platelet aggregation and thromboxane synthesis in response to collagen whereas no modification of platelet aggregation in response to thromboxane receptor agonist, U46619, was observed. Using COS-7 cells overexpressing human cyclooxygenase-1, we showed that these compounds are specific inhibitors of cyclooxygenase-1 with IC50 ranging from 1.3 to 12 μM. Docking observation of human recombinant cyclooxygenase-1 supported a role of the phenol group in the fitting of cyclooxygenase-1, most likely related to hydrogen bonding with the Tyr 355 of cyclooxygenase-1. Conclusions In conclusion, the compounds we synthesized at first based on the structures of analogues of 12 lipoxygenase metabolites showed a role of the phenol group in the anti-platelet and anti-cyclooxygenase-1 activities

  12. B cells and platelets harbor prion infectivity in the blood of deer infected with chronic wasting disease.

    Science.gov (United States)

    Mathiason, Candace K; Hayes-Klug, Jeanette; Hays, Sheila A; Powers, Jenny; Osborn, David A; Dahmes, Sallie J; Miller, Karl V; Warren, Robert J; Mason, Gary L; Telling, Glenn C; Young, Alan J; Hoover, Edward A

    2010-05-01

    Substantial evidence for prion transmission via blood transfusion exists for many transmissible spongiform encephalopathy (TSE) diseases. Determining which cell phenotype(s) is responsible for trafficking infectivity has important implications for our understanding of the dissemination of prions, as well as their detection and elimination from blood products. We used bioassay studies of native white-tailed deer and transgenic cervidized mice to determine (i) if chronic wasting disease (CWD) blood infectivity is associated with the cellular versus the cell-free/plasma fraction of blood and (ii) in particular if B-cell (MAb 2-104(+)), platelet (CD41/61(+)), or CD14(+) monocyte blood cell phenotypes harbor infectious prions. All four deer transfused with the blood mononuclear cell fraction from CWD(+) donor deer became PrP(CWD) positive by 19 months postinoculation, whereas none of the four deer inoculated with cell-free plasma from the same source developed prion infection. All four of the deer injected with B cells and three of four deer receiving platelets from CWD(+) donor deer became PrP(CWD) positive in as little as 6 months postinoculation, whereas none of the four deer receiving blood CD14(+) monocytes developed evidence of CWD infection (immunohistochemistry and Western blot analysis) after 19 months of observation. Results of the Tg(CerPrP) mouse bioassays mirrored those of the native cervid host. These results indicate that CWD blood infectivity is cell associated and suggest a significant role for B cells and platelets in trafficking CWD infectivity in vivo and support earlier tissue-based studies associating putative follicular B cells with PrP(CWD). Localization of CWD infectivity with leukocyte subpopulations may aid in enhancing the sensitivity of blood-based diagnostic assays for CWD and other TSEs. PMID:20219916

  13. Critical study of the in vitro labelling of circulating blood platelets

    International Nuclear Information System (INIS)

    At present it is possible by chromium-51 labelling in vitro to measure the platelet lifetime in man under normal conditions and in most thrombopenic states. Unfortunately this technique cannot be used for autologous platelet labelling in subjects possessing less than 80.000 platelets per mm3, while isologous labelling cannot distinguish between corpuscular and extracorpuscular anomalies. Moreover in most cases the aspect of the platelet survival curve obtained with 51Cr labelling provides no decisive argument as to the role of senescence and that of 'consumption' in platelet destruction. It seems that the use of indium-111 for the study of platelet survival parameters can supply certain positive elements: - kinetic study of autologous platelets in very low content thrombopenias since the number of platelets put to incubate seems to have little effect on the labelling yield. - Simultaneous isologue-autologue study by 51Cr - 111In double labelling to distinguish between corpuscular and extracorpuscular mechanisms. - Possible static and/or dynamic scintigraphic visualization of thromboses and/or atheromatous lesions with indium-113m - labelled platelets in the hope of obtaining some additional information on platelet 'consumption', at least in pathological cases

  14. The effect of ticlopidine administration to humans on the binding of adenosine diphosphate to blood platelets

    OpenAIRE

    Lips, J.P.M.; Sixma, J.J.; Schiphorst, M.E.

    1980-01-01

    Administration of Ticlopidine to human volunteers resulted in a prolonged bleeding time and decreased or absent aggregation of platelets with collagen and epinephrine. Adenosine diphosphate (ADP) induced platelet aggregation was initiated by a normal shape change, but the rate of the first wave of aggregation had decreased. The second wave of aggregation was absent. ADP-binding to platelets of volunteers, consisted of two classes of binding sites:one with high affinity and one with low affini...

  15. Relationship between the Increased Haemostatic Properties of Blood Platelets and Oxidative Stress Level in Multiple Sclerosis Patients with the Secondary Progressive Stage

    Directory of Open Access Journals (Sweden)

    Agnieszka Morel

    2015-01-01

    Full Text Available Multiple sclerosis (MS is the autoimmune disease of the central nervous system with complex pathogenesis, different clinical courses and recurrent neurological relapses and/or progression. Despite various scientific papers that focused on early stage of MS, our study targets selective group of late stage secondary progressive MS patients. The presented work is concerned with the reactivity of blood platelets in primary hemostasis in SP MS patients. 50 SP MS patients and 50 healthy volunteers (never diagnosed with MS or other chronic diseases were examined to evaluate the biological activity of blood platelets (adhesion, aggregation, especially their response to the most important physiological agonists (thrombin, ADP, and collagen and the effect of oxidative stress on platelet activity. We found that the blood platelets from SP MS patients were significantly more sensitive to all used agonists in comparison with control group. Moreover, the platelet hemostatic function was advanced in patients suffering from SP MS and positively correlated with increased production of O2-∙ in these cells, as well as with Expanded Disability Status Scale. We postulate that the increased oxidative stress in blood platelets in SP MS may be primarily responsible for the altered haemostatic properties of blood platelets.

  16. Whole blood coagulation and platelet activation in the athlete: A comparison of marathon, triathlon and long distance cycling

    Directory of Open Access Journals (Sweden)

    Hanke AA

    2010-02-01

    Full Text Available Abstract Introduction Serious thrombembolic events occur in otherwise healthy marathon athletes during competition. We tested the hypothesis that during heavy endurance sports coagulation and platelets are activated depending on the type of endurance sport with respect to its running fraction. Materials and Methods 68 healthy athletes participating in marathon (MAR, running 42 km, n = 24, triathlon (TRI, swimming 2.5 km + cycling 90 km + running 21 km, n = 22, and long distance cycling (CYC, 151 km, n = 22 were included in the study. Blood samples were taken before and immediately after completion of competition to perform rotational thrombelastometry. We assessed coagulation time (CT, maximum clot firmness (MCF after intrinsically activation and fibrin polymerization (FIBTEM. Furthermore, platelet aggregation was tested after activation with ADP and thrombin activating peptide 6 (TRAP by using multiple platelet function analyzer. Results Complete data sets were obtained in 58 athletes (MAR: n = 20, TRI: n = 19, CYC: n = 19. CT significantly decreased in all groups (MAR -9.9%, TRI -8.3%, CYC -7.4% without differences between groups. In parallel, MCF (MAR +7.4%, TRI +6.1%, CYC +8.3% and fibrin polymerization (MAR +14.7%, TRI +6.1%, CYC +8.3% were significantly increased in all groups. However, platelets were only activated during MAR and TRI as indicated by increased AUC during TRAP-activation (MAR +15.8% and increased AUC during ADP-activation in MAR (+50.3% and TRI (+57.5%. Discussion While coagulation is activated during physical activity irrespective of type we observed significant platelet activation only during marathon and to a lesser extent during triathlon. We speculate that prolonged running may increase platelet activity, possibly, due to mechanical alteration. Thus, particularly prolonged running may increase the risk of thrombembolic incidents in running athletes.

  17. The miRNA Profile of Platelets Stored in a Blood Bank and Its Relation to Cellular Damage from Storage.

    Science.gov (United States)

    Pontes, Thaís Brilhante; Moreira-Nunes, Caroline de Fátima Aquino; Maués, Jersey Heitor da Silva; Lamarão, Letícia Martins; de Lemos, José Alexandre Rodrigues; Montenegro, Raquel Carvalho; Burbano, Rommel Mário Rodriguez

    2015-01-01

    Millions of blood products are transfused each year, and many lives are directly affected by transfusion. Platelet concentrate (PC) is one of the main products derived from blood. Even under good storage conditions, PC is likely to suffer cell damage. The shape of platelets changes after 5 to 7 days of storage at 22°C. Taking into consideration that some platelet proteins undergo changes in their shape and functionality during PC storage. Sixteen PC bags were collected and each PC bag tube was cut into six equal pieces to perform experiments with platelets from six different days of storage. Thus, on the first day of storage, 1/6 of the tube was used for miRNA extraction, and the remaining 5/6 was stored under the same conditions until extraction of miRNAs on each the following five days. Samples were sequenced on an Illumina Platform to demonstrate the most highly expressed miRNAs. Three miRNAs, mir127, mir191 and mir320a were validated by real-time quantitative PCR (RQ-PCR) in 100 PC bags tubes. Our method suggests, the use of the miRNAs mir127 and mir320a as biomarkers to assess the "validity period" of PC bags stored in blood banks for long periods. Thus, bags can be tested on the 5th day of storage for the relative expression levels of mir127 and mir320a. Thus, we highlight candidate miRNAs as biomarkers of storage damage that can be used as tools to evaluate the quality of stored PC. The use of miRNAs as biomarkers of damage is unprecedented and will contribute to improved quality of blood products for transfusions. PMID:26121269

  18. Acquired platelet function defect

    Science.gov (United States)

    ... dark black, or tarry bowel movements ; or vomiting blood or material that looks like coffee grounds Nosebleeds ... Tests that may done include: Bleeding time Platelet aggregation test Platelet count PT and PTT

  19. CEREBRAL BLOOD FLOW AND METABOLISM IN ANXIETY AND ANXIETY DISORDERS

    OpenAIRE

    Mathew, Roy J.

    1994-01-01

    Anxiety disorders are some of the commonest psychiatric disorders and anxiety commonly co-exists with other psychiatric conditions. Anxiety can also be a normal emotion. Thus, study of the neurobiological effects of anxiety is of considerable significance. In the normal brain, cerebral blood flow (CBF) and metabolism (CMR) serve as indices of brain function. CBF/CMR research is expected to provide new insight into alterations in brain function in anxiety disorders and other psychiatric disord...

  20. Genetic engineering of platelets to neutralize circulating tumor cells.

    Science.gov (United States)

    Li, Jiahe; Sharkey, Charles C; Wun, Brittany; Liesveld, Jane L; King, Michael R

    2016-04-28

    Mounting experimental evidence demonstrates that platelets support cancer metastasis. Within the circulatory system, platelets guard circulating tumor cells (CTCs) from immune elimination and promote their arrest at the endothelium, supporting CTC extravasation into secondary sites. Neutralization of CTCs in blood circulation can potentially attenuate metastases to distant organs. Therefore, extensive studies have explored the blockade of platelet-CTC interactions as an anti-metastatic strategy. Such an intervention approach, however, may cause bleeding disorders since the platelet-CTC interactions inherently rely on the blood coagulation cascade including platelet activation. On the other hand, platelets have been genetically engineered to correct inherited bleeding disorders in both animal models and human clinical trials. In this study, inspired by the physical association between platelets and CTCs, platelets were genetically modified to express surface-bound tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a cytokine known to induce apoptosis specifically in tumor cells. The TRAIL-expressing platelets were demonstrated to kill cancer cells in vitro and significantly reduce metastases in a mouse model of prostate cancer metastasis. Our results suggest that using platelets to produce and deliver cancer-specific therapeutics can provide a Trojan-horse strategy of neutralizing CTCs to attenuate metastasis. PMID:26921521

  1. The saliva proteome of the blood-feeding insect Triatoma infestans is rich in platelet-aggregation inhibitors

    Science.gov (United States)

    Charneau, Sébastien; Junqueira, Magno; Costa, Camila M.; Pires, Daniele L.; Fernandes, Ellen S.; Bussacos, Ana C.; Sousa, Marcelo V.; Ricart, Carlos André O.; Shevchenko, Andrej; Teixeira, Antonio R. L.

    2007-12-01

    The saliva of the bloodsucking bug Triatoma infestans vector of Chagas disease contains an anti-hemostatic molecular cocktail that prevents coagulation, vasoconstriction and platelet aggregation in a vertebrate prey. In order to characterize T. infestans saliva proteome, we separated the secreted saliva by two-dimensional gel electrophoresis (2-DE). More than 200 salivary proteins were detected on the 2-DE map, mainly in the alkaline region. By nanoLC-MS/MS analysis using a LTQ-Orbitrap equipment followed by a combination of conventional and sequence-similarity searches, we identified 58 main protein spots. Most of such proteins possess potential blood-feeding associated functions, particularly anti-platelet aggregation proteins belonging to lipocalin and apyrase families. The saliva protein composition indicates a highly specific molecular mechanism of early response to platelet aggregation. This first proteome analysis of the T. infestans secreted saliva provides a basis for a better understanding of this fluid protein composition highly directed to counterpart hemostasis of the prey, thus promoting the bug's blood-feeding.

  2. Isolation of a 5-kilodalton actin-sequestering peptide from human blood platelets.

    OpenAIRE

    Safer, D; Golla, R; Nachmias, V T

    1990-01-01

    Resting human platelets contain approximately 0.3 mM unpolymerized actin. When freshly drawn and washed platelets are treated with saponin, 85-90% of the unpolymerized actin diffuses out. Analysis by polyacrylamide gel electrophoresis under nondenaturing conditions shows that the bulk of this unpolymerized actin migrates with a higher mobility than does pure G-actin, profilactin, or actin-gelsolin complex. When muscle G-actin is added to fresh or boiled saponin extract, the added muscle actin...

  3. Assessment of the influence of the inflammatory process on the activation of blood platelets and morphological parameters in patients with ulcerative colitis (colitis ulcerosa

    Directory of Open Access Journals (Sweden)

    Halina Kemona

    2011-04-01

    Full Text Available Ulcerative colitis (colitis ulcerosa is a non-specific inflammatory bowel disease of unknown etiology. The symptoms which are observed in the course of ulcerative colitis are: an increase in the number of leukocytes and blood platelets, an increase in the concentration of IL-6 and anemia. Blood platelets are the key element, linking the processes of hemostasis, inflammation and the repair of damaged tissues. Activation of blood platelets is connected with changes in their shape and the occurrence of the reaction of release. P-selectin appears on the surfaces of activated blood platelets and the concentration level of soluble P-selectin increases in the blood plasma. The aim of this study was to define whether the increased number of blood platelets in patients with ulcerative colitis accompanies changes in their activation and morphology. A total of 16 subjects with ulcerative colitis and 32 healthy subjects were studied. Mean platelet count, morphological parameters of platelets and MPC were measured using an ADVIA 120 hematology analyzer. Concentrations of sP-selectin and IL-6 in serum were marked by immunoassay (ELISA. MPC, concentration of sP-selectin and IL-6 were significantly higher in subjects with ulcerative colitis compared to those in the healthy group. There was a decrease of MPV in patients with ulcerative colitis, which is statistically significant. Chronic inflammation in patients with ulcerative colitis causes an increase in the number of blood platelets, a change in their morphology and activation. Decreased MPV value reflects activation and the role blood platelets play in the inflammatory process of the mucous membrane of the colon. A high concentration of sP-selectin, which is a marker of blood platelet activation, demonstrates their part in the inflammatory process. The increase in the concentration of sP-selectin correlated positively with the increase in concentration of IL-6. This is why it may be a useful marker

  4. A novel blood incubation system for the in-vitro assessment of interactions between platelets and biomaterial surfaces under dynamic flow conditions: The Hemocoater.

    Science.gov (United States)

    Boudot, Cécile; Boccoz, Ana; Düregger, Katharina; Kuhnla, Ariane

    2016-10-01

    Hemocompatibility evaluation of biomaterials necessitates the use of blood incubation systems which simulate physiological flow conditions. However, most of the current systems have various limitations, especially restricted material variability, poor access to the test surface or damage of blood cells due to the use of a pump. In this paper, we combined the advantages of existent setups and developed a new planar shaped incubation test bench to lift those restrictions and mimic the pulsatile in-vivo situation. The adjustable flow conditions at the tested material surface were defined and corresponded to those in blood vessels. Platelet/material-interaction, as major aspect of hemocompatibility, was investigated for four common polymeric materials (polyoxymethylene, polypropylene, polyethylene and silicone elastomer) with platelet deprivation and platelet adhesion tests. Highly significant differences in the adhesion of platelets onto the tested material surfaces were measured. The number of adhered platelets on the most hydrophobic sample (silicone elastomer) was four-times higher than on the most hydrophilic sample (polyoxymethylene). These findings were confirmed with a scanning microscopic analysis and demonstrated the suitability of the testing device for the evaluation of platelet/material interactions. Moreover, hemolysis measurements demonstrated that the system did not provoke blood damage. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2430-2440, 2016. PMID:27213915

  5. Flow cytometric comparison of platelets from a whole blood and finger-prick sample: impact of 24 hours storage.

    Science.gov (United States)

    Swanepoel, Albe C; Stander, Andre; Pretorius, Etheresia

    2013-03-01

    In this study, we investigate the validity and laboratory utility of flow cytometry when analyzing platelet activation by studying CD41, CD42b, CD62P and CD63. We compare flow cytometry results from citrated whole-blood and finger-prick samples directly after collection and also after storing both a finger-prick and whole-blood sample for 24 hours. Citrated whole-blood and finger-prick samples were taken from three healthy individuals on two occasions, and a total of 60,000 cells were analyzed for each of the four phycoerythrin-labeled monoclonal antibodies. Half of each sample was analyzed immediately after sampling while the other half was kept in the fridge at 6 °C for 24 hours before analysis. No significant difference was found between the sampling methods or the period of time before analysis. Results therefore suggest that an appropriately prepared finger-prick sample can be used for platelet function analysis, and samples can be stored for 24 hours in the fridge at 6 °C before analysis. PMID:23320994

  6. Increases in platelet and red cell counts, blood viscosity, and arterial pressure during mild surface cooling: factors in mortality from coronary and cerebral thrombosis in winter.

    OpenAIRE

    Keatinge, W R; Coleshaw, S R; Cotter, F.; Mattock, M; Murphy, M; Chelliah, R

    1984-01-01

    Six hours of mild surface cooling in moving air at 24 degrees C with little fall in core temperature (0.4 degree C) increased the packed cell volume by 7% and increased the platelet count and usually the mean platelet volume to produce a 15% increase in the fraction of plasma volume occupied by platelets. Little of these increases occurred in the first hour. Whole blood viscosity increased by 21%; plasma viscosity usually increased, and arterial pressure rose on average from 126/69 to 138/87 ...

  7. Generation of mesenchymal stromal cells in the presence of platelet lysate: a phenotypic and functional comparison of umbilical cord blood- and bone marrow-derived progenitors

    OpenAIRE

    Avanzini, Maria Antonietta; Bernardo, Maria Ester; Cometa, Angela Maria; Perotti, Cesare; Zaffaroni, Nadia; Novara, Francesca; Visai, Livia; Moretta, Antonia; Del Fante, Claudia; Villa, Raffaella; Ball, Lynne M.; Fibbe, Willem E; Maccario, Rita; Locatelli, Franco

    2009-01-01

    Umbilical cord blood is an attractive source of stem cells for several cell-based therapies. In this paper, it is shown that umbilical cord blood-derived mesenchymal stroma cells, cultured in the presence of platelet lysate, have an increased proliferative potential but comparable immunomodulatory functions relative to their bone marrow-derived counterparts.

  8. Transmission of Neurodegenerative Disorders Through Blood Transfusion

    DEFF Research Database (Denmark)

    Edgren, Gustaf; Hjalgrim, Henrik; Rostgaard, Klaus;

    2016-01-01

    Background: The aggregation of misfolded proteins in the brain occurs in several neurodegenerative disorders. Aberrant protein aggregation is inducible in rodents and primates by intracerebral inoculation. Possible transfusion transmission of neurodegenerative diseases has important public health...... implications. Objective: To investigate possible transfusion transmission of neurodegenerative disorders. Design: Retrospective cohort study. Setting: Nationwide registers of transfusions in Sweden and Denmark. Participants: 1 465 845 patients who received transfusions between 1968 and 2012. Measurements......: Observational study design, underascertainment of the outcome, and possible insufficient statistical power. Conclusion: The data provide no evidence for the transmission of neurodegenerative diseases and suggest that if transmission does occur, it is rare. Primary Funding Source: Swedish Research Council...

  9. Effect of a New Antioxidant Enoxifol on Platelet Aggregation and Blood Rheological Properties in Rats with Experimental Diabetes Mellitus.

    Science.gov (United States)

    Kucheryavenko, A F; Spasov, A A; Anisimova, V A

    2016-04-01

    Effect of a new antioxidant enoxifol exhibiting antiplatelet activity in vitro and in vivo on hemostasis parameters was assessed in laboratory rats with experimental diabetes mellitus. Gliclazide, a hypoglycemic agent with antiplatelet properties, and pentoxifylline, a preparation improving blood rheology, were used as the reference drugs. Enoxifol produced a pronounced inhibitory effect on platelet aggregation in rats with experimental diabetes comparable to the effect of gliclazide and decreased blood viscosity thus demonstrating a significant effect comparable to that of pentoxifylline. In view of the fact that oxidative stress is a pathogenetic components of vascular complications in diabetes, it can be assumed that improvement of hemostasis parameters under the effect of enoxifol is determined by its antiplatelet and antioxidant activities. PMID:27165061

  10. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Ioana Mozos

    2015-01-01

    Full Text Available The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular diseases, and targets for hemoglobin level should be established. Risk scores in several cardiovascular diseases should include red blood cell count and RDW. Complete blood count and hemorheological parameters represent useful, inexpensive, widely available tools for the management and prognosis of patients with coronary heart disease, heart failure, hypertension, arrhythmias, and stroke. Hypoxia and iron accumulation cause the most important cardiovascular effects of sickle cell disease and thalassemia. Patients with congenital chronic hemolytic anemia undergoing splenectomy should be monitored, considering thromboembolic and cardiovascular risk.

  11. A high-throughput sequencing test for diagnosing inherited bleeding, thrombotic, and platelet disorders.

    Science.gov (United States)

    Simeoni, Ilenia; Stephens, Jonathan C; Hu, Fengyuan; Deevi, Sri V V; Megy, Karyn; Bariana, Tadbir K; Lentaigne, Claire; Schulman, Sol; Sivapalaratnam, Suthesh; Vries, Minka J A; Westbury, Sarah K; Greene, Daniel; Papadia, Sofia; Alessi, Marie-Christine; Attwood, Antony P; Ballmaier, Matthias; Baynam, Gareth; Bermejo, Emilse; Bertoli, Marta; Bray, Paul F; Bury, Loredana; Cattaneo, Marco; Collins, Peter; Daugherty, Louise C; Favier, Rémi; French, Deborah L; Furie, Bruce; Gattens, Michael; Germeshausen, Manuela; Ghevaert, Cedric; Goodeve, Anne C; Guerrero, Jose A; Hampshire, Daniel J; Hart, Daniel P; Heemskerk, Johan W M; Henskens, Yvonne M C; Hill, Marian; Hogg, Nancy; Jolley, Jennifer D; Kahr, Walter H; Kelly, Anne M; Kerr, Ron; Kostadima, Myrto; Kunishima, Shinji; Lambert, Michele P; Liesner, Ri; López, José A; Mapeta, Rutendo P; Mathias, Mary; Millar, Carolyn M; Nathwani, Amit; Neerman-Arbez, Marguerite; Nurden, Alan T; Nurden, Paquita; Othman, Maha; Peerlinck, Kathelijne; Perry, David J; Poudel, Pawan; Reitsma, Pieter; Rondina, Matthew T; Smethurst, Peter A; Stevenson, William; Szkotak, Artur; Tuna, Salih; van Geet, Christel; Whitehorn, Deborah; Wilcox, David A; Zhang, Bin; Revel-Vilk, Shoshana; Gresele, Paolo; Bellissimo, Daniel B; Penkett, Christopher J; Laffan, Michael A; Mumford, Andrew D; Rendon, Augusto; Gomez, Keith; Freson, Kathleen; Ouwehand, Willem H; Turro, Ernest

    2016-06-01

    Inherited bleeding, thrombotic, and platelet disorders (BPDs) are diseases that affect ∼300 individuals per million births. With the exception of hemophilia and von Willebrand disease patients, a molecular analysis for patients with a BPD is often unavailable. Many specialized tests are usually required to reach a putative diagnosis and they are typically performed in a step-wise manner to control costs. This approach causes delays and a conclusive molecular diagnosis is often never reached, which can compromise treatment and impede rapid identification of affected relatives. To address this unmet diagnostic need, we designed a high-throughput sequencing platform targeting 63 genes relevant for BPDs. The platform can call single nucleotide variants, short insertions/deletions, and large copy number variants (though not inversions) which are subjected to automated filtering for diagnostic prioritization, resulting in an average of 5.34 candidate variants per individual. We sequenced 159 and 137 samples, respectively, from cases with and without previously known causal variants. Among the latter group, 61 cases had clinical and laboratory phenotypes indicative of a particular molecular etiology, whereas the remainder had an a priori highly uncertain etiology. All previously detected variants were recapitulated and, when the etiology was suspected but unknown or uncertain, a molecular diagnosis was reached in 56 of 61 and only 8 of 76 cases, respectively. The latter category highlights the need for further research into novel causes of BPDs. The ThromboGenomics platform thus provides an affordable DNA-based test to diagnose patients suspected of having a known inherited BPD. PMID:27084890

  12. Healthy pregnancy and prenatal disorders followed by blood plasma metabolomics

    OpenAIRE

    Pinto, Joana Isabel Monteiro

    2015-01-01

    The work presented in this thesis aimed to investigate the impact of healthy pregnancy and selected prenatal disorders on the metabolome and lipidome of maternal blood plasma, in order to define new potential biomarkers for non-invasive prediction and diagnosis. Chapter 1 describes the present status and challenges of the clinically relevant prenatal disorders, along with a presentation of the metabolomics strategy applied and the state of the art of metabolomics in prenatal research. All ...

  13. The effect of two beta-adrenoceptor blockers (mepindolol and atenolol) on blood lipids and platelet aggregation in normal volunteers and essential hypertensive patients.

    OpenAIRE

    Luque Otero, M; Fernandez Pinilla, C; Escriba Polo, A; Rodriguez Vazquez, M; Martell Claros, N; A Fernandez-Cruz

    1984-01-01

    beta-adrenoceptor blocking agents are widely used as treatment of essential hypertension. We studied the action of a new non cardioselective beta-adrenoceptor blocker, mepindolol, comparing its effects on blood pressure, blood lipids and platelet aggregation with those of a cardioselective beta-adrenoceptor blocker, atenolol. Blood pressure fell significantly in the patients treated with both drugs. Triglycerides rose non-significantly only in volunteers treated with mepindolol. We did not fi...

  14. Incidence of thrombocytopenia and changes in various platelet parameters, in blood culture positive neonatal sepsis

    OpenAIRE

    Sartaj Bhat; Suhail Naik; Wasim Rafiq; Syed Tariq A

    2015-01-01

    Abstract Objective: To assess the incidence of thrombocytopenia and changes in various platelet parameters, in culture positive neonatal sepsis. Methods: This was prospective study conducted over a period of one year from December 2009 to November 2010 in neonatal intensive care unit of DDUH Hospital, a tertiary care hospital in Delhi, North India. All babies who were admitted during this period were evaluated prospectively for evidence of sepsis. Results: sepsis was diagnosed in 560 neonates...

  15. Storage of biogenic amines in intact blood platelets of man. Dependence on a proton gradient

    International Nuclear Information System (INIS)

    The actions of ionophores with different ion specificities and of thrombin on the release of 14C-labeled 5-hydroxytryptamine, [3H]noradrenaline, and endogenous ATP were measured in human platelets suspended in media with various K+ and Na+ concentrations. Besides thrombin, those ionophores [monensin, nigericin, and the combination of carbonylcyanide-p-trifluoromethoxyphenyl hydrazone (FCCP) with nonactin and/or valinomycin] which cause a rapid collapse of H+ gradients induced a fast and virtually total release of 14C-labeled 5-hydroxytryptamine and [3H]noradrenaline into the various media. FCCP alone, which causes an inversion of the membrane potential to inside negative values, induced a considerably slower amine release. Changes in the K+ and Na+ gradients did not lead to amine release, nor did interference with energy transduction by antimycin A with or without glycolysis inhibitors. Monensin and FCCP did not release ATP, whereas thrombin, added before or after incubation of platelets with FCCP and monensin, caused a marked liberation of the nucleotide. It is concluded that in intact human platelets (a) the intragranular storage of 5-hydroxytryptamine and noradrenaline mainly depends on the proton gradient across the granular membrane, and (b) ionophores causing a collapse of H+ gradients induce non-exocytotic release of 5-hydroxytryptamine and noradrenaline from intracellular storage granules

  16. Blood and Brain Glutamate Levels in Children with Autistic Disorder

    Science.gov (United States)

    Hassan, Tamer H.; Abdelrahman, Hadeel M.; Fattah, Nelly R. Abdel; El-Masry, Nagda M.; Hashim, Haitham M.; El-Gerby, Khaled M.; Fattah, Nermin R. Abdel

    2013-01-01

    Despite of the great efforts that move forward to clarify the pathophysiologic mechanisms in autism, the cause of this disorder, however, remains largely unknown. There is an increasing body of literature concerning neurochemical contributions to the pathophysiology of autism. We aimed to determine blood and brain levels of glutamate in children…

  17. Peripheral blood brain-derived neurotrophic factor in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, K; Vinberg, M; Kessing, L V

    2016-01-01

    Peripheral blood brain-derived neurotrophic factor (BDNF) has been proposed as a potential biomarker related to disease activity and neuroprogression in bipolar disorder, speculated to mirror alterations in brain expression of BDNF. The research area is rapidly evolving; however, recent...... investigations have yielded conflicting results with substantial variation in outcomes, highlighting the need to critically assess the state of current evidence. The aims of the study were to investigate differences in peripheral blood BDNF concentrations between bipolar disorder patients and healthy control...... subjects and between affective states in bipolar disorder patients, including assessment of the effect of treatment of acute episodes on BDNF levels. A systematic review of English language studies without considering publication status was conducted in PubMed (January 1950-November 2014), Embase (1974...

  18. Evaluation of the correlation between pH and MPV platelet concentrates prepared in Tirana Blood Transfusion Center.

    Directory of Open Access Journals (Sweden)

    MERITA XHETANI

    2014-06-01

    Full Text Available The quality of platelet concentrates is an important option in transfusion therapy. pH and platelet indices have been found to be valuable parameters for monitoring the in vitro quality of platelet concentrates. Platelet activation which leads to loss of its functionality has been demonstrated by changes in those two parameters. The aim of the study was to evaluate the correlation between pH and mean platelet volume (MPV in platelet concentrates in order to examine the quality of platelet concentrate. 150 units of platelet concentrates were produced by platelet reach plasma (PRP, and stored for 5 days. Then MPV and pH were analyzed by automated hematological cell counter and Ph meter respectively. Regression analysis showed that there was a significant influence of pH changes on the changes in MPV. On the other hand, increase in pH lead to decrease in MPV. Storing platelet concentrates up to 5 days may stimulate platelet activity, enhancing its size and resulted in its destruction, so the remaining platelet are those with significantly lower MPV. Also platelet activation was those with an increase in pH. As a result measurements of MPV and pH have a great potential as quality markers of platelet concentrates.

  19. Effects of dermatan sulfate derivatives on platelet surface P-selectin expression and protein C activity in blood of inflammatory bowel disease patients

    OpenAIRE

    Ji, Sheng-Li; Du, Hai-Yan; Chi, Yan-Qing; Cui, Hui-Fei; Cao, Ji-Chao; Geng, Mei-yu; Guan, Hua-Shi

    2004-01-01

    AIM: To investigate the effect of dermatan sulfate (DS) derivatives on platelet surface P-selectin expression and blood activated protein C (APC) activity in patients with inflammatory bowel disease (IBD), and to clarity the anti-inflammatory mechanism of DS derivatives.

  20. Platelet receptor interplay regulates collagen-induced thrombus formation in flowing human blood.

    Science.gov (United States)

    Siljander, Pia R-M; Munnix, Imke C A; Smethurst, Peter A; Deckmyn, Hans; Lindhout, Theo; Ouwehand, Willem H; Farndale, Richard W; Heemskerk, Johan W M

    2004-02-15

    The platelet glycoproteins (GPs) Ib, integrin alpha(2)beta(1), and GPVI are considered central to thrombus formation. Recently, their relative importance has been re-evaluated based on data from murine knockout models. To examine their relationship during human thrombus formation on collagen type I fibers at high shear (1000 s(-1)), we tested a novel antibody against GPVI, an immunoglobulin single-chain variable fragment, 10B12, together with specific antagonists for GPIb alpha (12G1 Fab(2)) and alpha(2)beta(1) (6F1 mAb or GFOGER-GPP peptide). GPVI was found to be crucial for aggregate formation, Ca(2+) signaling, and phosphatidylserine (PS) exposure, but not for primary adhesion, even with more than 97% receptor blockade. Inhibiting alpha(2)beta(1) revealed its involvement in regulating Ca(2+) signaling, PS exposure, and aggregate size. Both GPIb alpha and alpha(2)beta(1) contributed to primary adhesion, showing overlapping function. The coinhibition of receptors revealed synergism in thrombus formation: the coinhibition of adenosine diphosphate (ADP) receptors with collagen receptors further decreased adhesion and aggregation, and, crucially, the complete eradication of thrombus formation required the coinhibition of GPVI with either GPIb alpha or alpha(2)beta(1). In summary, human platelet deposition on collagen depends on the concerted interplay of several receptors: GPIb in synergy with alpha(2)beta(1) mediating primary adhesion, reinforced by activation through GPVI, which further regulates the thrombus formation. PMID:14563646

  1. Effect of some saturated and unsaturated fatty acids on prostaglandin biosynthesis in washed human blood platelets from (1-/sup 14/ C)arachidonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, K.C.; Awasthi, K.K.; Lindegard, P.; Tiwari, K.P.

    1982-03-01

    The effects of some saturated (lauric, palmitic and stearic) an unsaturated (linoleic, gamma-linolenic, alpha-linolenic and oleic) fatty acids at 0.1. 0.25 and 0.5 mM concentrations on the in vitro metabolization of (1-14 C) arachidonic acid by washed human blood platelets have been studied. Effects of these fatty acids were studied with intact as well as lysed platelet preparations. With intact platelet preparations it was found that (i) all unsaturated fatty acids enhanced the biosynthesis of TxB2, PGE2, PGD2 and PGF2 alpha, (ii) unsaturated fatty acids reduced the formation of HHT and HETE with the exception of oleic acid which showed very little effect, (iii) unsaturated fatty acids reduced the formation of MDA, whereas palmitic and stearic acids increased its formation and (iv) all unsaturated fatty acids reduced the synthesis of prostaglandin endoperoxides. These results support our previous observations where effects of fatty acids were examined at higher concentrations (10). At 0.1 mM FA concentration, inconsistent results were obtained. With lysed platelet preparations all cyclooxygenase products were reduced in presence of unsaturated fatty acids, whereas HETE formation was reduced only in presence of linoleic and gamma-linolenic acids. Electron micrographs of washed platelet suspensions were obtained with untreated platelet preparations and platelet preparations treated with 0.25 and 0.5 mM linoleic acid concentrations. The results are discussed in the light of a possible soap-like effect of FA salt on platelets.

  2. Platelet size and age determine platelet function independently

    International Nuclear Information System (INIS)

    A study was undertaken to examine the interaction of platelet size and age in determining in vitro platelet function. Baboon megakaryocytes were labeled in vivo by the injection of 75Se-methionine. Blood was collected when the label was predominantly associated with younger platelets (day 2) and with older platelets (day 9). Size-dependent platelet subpopulations were prepared on both days by counterflow centrifugation. The reactivity of each platelet subpopulation was determined on both days by measuring thrombin-induced aggregation. Platelets were fixed after partial aggregation had occurred by the addition of EDTA/formalin. After removal of the aggregated platelets by differential centrifugation, the supernatant medium was assayed for remaining platelets and 75Se radioactivity. Comparing day 2 and day 9, no significant difference was seen in the rate of aggregation of a given subpopulation. However, aggregation was more rapid in the larger platelet fractions than in the smaller ones on both days. A greater percentage of the 75Se radioactivity appeared in the platelet aggregates on day 2 than on day 9. This effect was independent of platelet size, as it occurred to a similar extent in the unfractionated platelets and in each of the size-dependent platelet subpopulations. The data indicate that young platelets are more active than older platelets. This study demonstrates that size and age are both determinants of platelet function, but by independent mechanisms

  3. White Blood Cell Count to Mean Platelet Volume Ratio Is a Prognostic Factor in Patients with Non-ST Elevation Acute Coronary Syndrome with or without Metabolic Syndrome

    OpenAIRE

    Dehghani, Mohammad Reza; Rezaei, Yousef; Fakour, Sanam; Arjmand, Nasim

    2016-01-01

    Background and Objectives Leukocyte and platelet have been found to be associated with metabolic syndrome (MetS). We aimed to determine the usefulness of a novel marker named white blood cell count to mean platelet volume ratio (WMR) for predicting outcomes of non-ST elevation acute coronary syndrome (NSTE-ACS) with or without MetS. Subjects and Methods A total of 331 NSTE-ACS individuals (60±12.5 years, 57.4% male) were enrolled and followed for a median of 24 months. MetS was identified usi...

  4. Properdin-Mediated C5a Production Enhances Stable Binding of Platelets to Granulocytes in Human Whole Blood.

    Science.gov (United States)

    Blatt, Adam Z; Saggu, Gurpanna; Kulkarni, Koustubh V; Cortes, Claudio; Thurman, Joshua M; Ricklin, Daniel; Lambris, John D; Valenzuela, Jesus G; Ferreira, Viviana P

    2016-06-01

    Enhanced levels of platelet/granulocyte aggregates (PGAs) are found in patients suffering from many different inflammatory vascular diseases, and their formation in animal models of vascular disease is associated with increased thromboinflammation and worsened outcomes. The complement system, a part of the innate immune system, influences PGA formation, but the mechanisms for its effects are unknown. In this study, we have defined complement-mediated mechanisms that enhance PGA formation in human whole blood stimulated with thrombin receptor-activating peptide (TRAP) using ex vivo flow cytometry assays. We demonstrate that physiological properdin, a positive regulator of complement alternative pathway activity, increases PGA formation when added to TRAP-stimulated blood. All physiological properdin forms increase PGA formation, but properdin tetramers are the most efficient at increasing complement activity and PGA formation. Inhibition of endogenous properdin, either circulating in the blood or produced locally by leukocytes, impairs TRAP-mediated PGA formation to the same level as specific inhibition of either the alternative or classical pathway. Additionally, blocking the interaction of C5a with its cellular receptor prevents properdin-mediated increases in PGA formation. Adding either properdin tetramers or C5a to whole blood increases CD11b expression on granulocytes, and this increase is prevented by blockade of the C5a-C5a receptor axis. Finally, we demonstrate that the effects of properdin on PGA formation are tightly regulated by Factor H. Cumulatively, our data indicate that properdin enhances PGA formation via increased production of C5a, and that inhibition of properdin function has therapeutic potential to limit thromboinflammation in diseases characterized by increased PGA formation. PMID:27183616

  5. Extracorporeal irradiation of calves blood. Effects on: the lymphocytes, the blood-platelet function, seric proteins, and fibrinogen

    International Nuclear Information System (INIS)

    The present paper reports the results obtained after extracorporeal irradiation of circulating blood of calves. Animals are divided in 3 groups as follows: - control animals: blood circulation without irradiation; - calves which received 40000 rads during 24 hours of continuous irradiation; - calves which received the same dose, during a period of 5 days (5 hours every day). The more interesting results are: - the early lymphopenia which persists for 7 or 8 weeks and may be in relationship with the change of immunoglobulins; - a constant hyperfibrinemia (12 g/l) never reported, as far as we know, by authors using I.E.C. Several hypothesis are advanced to explain this phenomenon. (authors)

  6. Effects of three novel metalloproteinases from the venom of the West African saw-scaled viper, Echis ocellatus on blood coagulation and platelets.

    Science.gov (United States)

    Howes, J-M; Kamiguti, A S; Theakston, R D G; Wilkinson, M C; Laing, G D

    2005-06-20

    Two metalloproteinases, a 24-kDa P-I EoVMP1 and a 56-kDa P-III EoVMP2, have recently been isolated from the venom of the West African saw-scaled viper Echis ocellatus. We now reveal a new 65-kDa haemorrhagic group P-III metalloproteinase which we have designated EoVMP3. The aim of this study was to determine whether these three snake venom metalloproteinases (SVMPs) affect platelets and blood coagulation. EoVMP1 had no effect on the aggregation of washed human platelets, whereas EoVMP2 inhibited collagen-induced platelet aggregation. In contrast, EoVMP3 did not inhibit the aggregation of platelets by collagen but instead activated platelets in the absence of any additional co-factors. All three SVMPs were capable of activating prothrombin to varying degrees and can therefore be described as procoagulants. EoVMP1, EoVMP2 and EoVMP3 share sequence identity with other members of the reprolysin family, but differ greatly in their effects on some of the components that control haemostasis. PMID:15863354

  7. Acetyl eugenol, a component of oil of cloves (Syzygium aromaticum L.) inhibits aggregation and alters arachidonic acid metabolism in human blood platelets.

    Science.gov (United States)

    Srivastava, K C; Malhotra, N

    1991-01-01

    In continuation of our studies with the oil of cloves--a common kitchen spice and a crude drug for home medicine--we have isolated yet another active component identified as acetyl eugenol (AE); the earlier reported active component being eugenol. The isolated material (IM) was found to be a potent platelet inhibitor; IM abolished arachidonate (AA)-induced aggregation at ca. 12 microM, a concentration needed to abolish the second phase of adrenaline-induced aggregation. Chemically synthesized acetyl eugenol showed similar effects on AA- and adrenaline-induced aggregation. A dose-dependent inhibition of collagen-induced aggregation was also observed. AE did not inhibit either calcium ionophore A23187- or thrombin-induced aggregation. Studies on aggregation and ATP release were done using whole blood (WB). AA-induced aggregation in WB was abolished at 3 micrograms/ml (14.6 microM) which persisted even after doubling the concentration of AA. ATP release was inhibited. Inhibition of aggregation appeared to be mediated by a combination of two effects: reduced formation of thromboxane and increased generation of 12-lipoxygenase product (12-HPETE). These effects were observed by exposing washed platelets to (14C)AA or by stimulating AA-labelled platelets with ionophore A23187. Acetyl eugenol inhibited (14C)TxB2 formation in AA-labelled platelets on stimulation with thrombin. AE showed no effect on the incorporation of AA into platelet phospholipids. PMID:2011614

  8. Brief Report: Normal Intestinal Permeability at Elevated Platelet Serotonin Levels in a Subgroup of Children with Pervasive Developmental Disorders in Curacao (The Netherlands Antilles)

    Science.gov (United States)

    Kemperman, Ramses F. J.; Muskiet, Fred D.; Boutier, A. Inge; Kema, Ido P.; Muskiet, Frits A. J.

    2008-01-01

    This study investigated the relationship between platelet (PLT) serotonin (5-HT) and intestinal permeability in children with pervasive developmental disorders (PDD). Differential sugar absorption and PLT 5-HT were determined in 23 children with PDD. PLT 5-HT (2.0-7.1 nmol/10[to the ninth power] PLT) was elevated in 4/23 patients. None exhibited…

  9. A revised model of platelet aggregation

    OpenAIRE

    Kulkarni, Suhasini; Dopheide, Sacha M.; Yap, Cindy L.; Ravanat, Catherine; Freund, Monique; Mangin, Pierre; Heel, Kathryn A.; Street, Alison; Harper, Ian S.; Lanza, Francois; Jackson, Shaun P.

    2000-01-01

    In this study we have examined the mechanism of platelet aggregation under physiological flow conditions using an in vitro flow-based platelet aggregation assay and an in vivo rat thrombosis model. Our studies demonstrate an unexpected complexity to the platelet aggregation process in which platelets in flowing blood continuously tether, translocate, and/or detach from the luminal surface of a growing platelet thrombus at both arterial and venous shear rates. Studies of platelets congenitally...

  10. Study of blood compatibility with poly(2-methoxyethyl acrylate). Relationship between water structure and platelet compatibility in poly(2-methoxyethylacrylate-co-2-hydroxyethylmethacrylate).

    Science.gov (United States)

    Tanaka, Masaru; Mochizuki, Akira; Ishii, Naoki; Motomura, Tadahiro; Hatakeyama, Tatsuko

    2002-01-01

    Previously, we reported that poly(2-methoxyethylacrylate) (PMEA) showed excellent blood compatibility and implied that the water structure in PMEA contributed to the blood compatibility. In this study, the relationship between the water structure and the blood compatibility is clarified by studying the influence of the monomer composition of poly(MEA-co-HEMA) on the water structure and the blood compatibility of the copolymers. The water in the polymer was classified into three types: free water, freezing bound water, and nonfreezing water. The polymers with 0-30 mol % of HEMA content had a significant amount of freezing bound water, and the amount decreases greatly when the composition of HEMA exceeded 30 mol %. On the other hand, the amount of other water increased simply with an increase of HEMA content. The evaluation of the platelet compatibility of poly(MEA-co-HEMA) revealed that the adhesion number and the morphological change of platelet on the copolymer surface were least when the HEMA content was 0-20 mol %. These two results strongly suggest that the freezing bound water relates to the platelet compatibility of the polymers. PMID:11866553

  11. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

    Full Text Available Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. The present study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, CSM Medical University, Lucknow. Random donor platelets were prepared by platelet rich plasma method. Whole blood (350 ml was collected in anticoagulant Citrate Phosphate Dextrose Adenine triple blood bags. Random donor platelets were stored for 7 days at 22°C in platelet incubators and agitators, with and without additive solution. Results: Platelet swirling was present in all the units at 22°C on day 7, with no evidence of bacterial contamination. Comparison of the mean values of platelet count, platelet factor 3, lactate dehydrogenase, pH, glucose and platelet aggregation showed no significant difference in additive solution, whereas platelet factor 3, glucose and platelet aggregation showed significant difference (P < 0.001 on day 7 without additive solution at 22°C. Conclusion: Our study infers that platelet viability and aggregation were best maintained within normal levels on day 7 of storage in platelet additive solution at 22°C. Thus, we may conclude that in vitro storage of random donor platelets with an extended shelf life of 7 days using platelet additive solution may be advocated to improve the inventory of platelets.

  12. Different Types of the Coagulation Disorders in Hamadan and A Comparison of the ABO & Rh Blood Group Distribution in the Patients and the Control Group

    Directory of Open Access Journals (Sweden)

    H. Pour-Jafari

    2003-10-01

    Full Text Available Patients with hemophilia and thalassemia are two groups of hereditary disorders that, periodically, use blood and blood substances. The aims of the present study are determination of the frequencies of different types of coagulation disorders, and a comparison of the frequencies of ABO & Rh phenotypes among affected individuals with the control group (blood donors. The subject group were all affected persons were referred to hemophilia and thalassemia centers in Hamadan. Primary information was collected from their files, then were classified and analyzed. The control group were blood donors that were registered in Hamadan blood bank. Results showed that the different types of coagulation disorders in affected individuals referred to the Hemophilia and thalassemia centers during 1998 were Hemophilia A (61.96%, Hemophilia B (20.86%, Von Willbrand (5.52%, Platelet deficiency (4.91%, Factor XIII deficiency (3.68% and Factor VII deficiency (3.07%. In general, results showed that in population with Hemophilia A, frequencies of A and O blood types were statistically different with the blood donors. The lowest rate of negative Rh, was in the population with thalassemia. The sex ratio of the affected persons was also different with control group.

  13. 多次捐献机采血小板后献血者外周血象的变化%The changes of peripheral blood indexes in donors donating blood several times for apheresis platelet concentrates*

    Institute of Scientific and Technical Information of China (English)

    葛健民; 赵宏祥; 任素玲; 袁秀珍

    2011-01-01

    Objective To study the changes of peripheral blood several times indexes in donors donating blood for apheresis platelet concentrates. Methods 20 donors who donated blood for apheresis platelet concentrates 10 38 times (interval: 1- 2 months), were enrolled and detected for peripheral blood indexes respectively before the first and the last time for donating platelet,and the results were analyzed. Results Of all enrolled donors, the platelet number, red blood cell number, white blood cell number and haemoglobin concentrates and the average value before the last donating blood were not statistical different with those before the first donating(P>0.05) ,but mean platelet volume and platelet large cell rate were decreased(P<0.01). Conclusion Blood do nation could promote hematopoiesis of the bone marrow,and might not be harmful to the body health.%目的 研究多次捐献机采血小板后献血者外周血象的变化情况.方法 选择20名自愿捐献机采血小板达10~38次的献血者(每次间隔期为1~2个月),在首次和末次采集血小板前分别进行外周血象的检测,进行统计分析.结果 多次捐献机采血小板的献血者,末次采集前外周血小板数(PLT)与首次采集前PLT、正常值均数相比,差异均无统计学意义(P>0.05),外周血中的红细胞数(RBC)、白细胞数(WBC)、血红蛋白浓度(Hb)并未发生明显的变化,但血小板分布宽度(PDW)增加,血小板平均体积(MPV)、大形血小板比例(P-LCR)下降,且差异有统计学意义(P<0.01).结论 献血可以促进骨髓的造血功能,对机体并无明显不利的影响.

  14. Storage of human red blood cells and platelets. Some aspects concerning the factors leading to storage lesion characterized as morphological changes and vesiculation. Minireview based on a doctoral thesis.

    Science.gov (United States)

    Solberg, C

    1988-01-01

    1. Storage renders erythrocytes more responsive to thermally induced morphological changes, especially the shedding of microvesicles. 4-8 week old cells can be morphologically "rejuvenated" by heating. 2. If pH increases during storage of platelets an extensive loss of small particles occurs. The platelet disintegration is associated with a loss in the metabolic activity, discharge of LDH, increased susceptibility to phospholipid hydrolysis by phospholipase C and is found to be initiated during the actual preparation of platelet concentrates. 3. Activation of platelets during preparation can be decreased by shortening the first centrifugation time or by using adenine in the anticoagulant. 4. A 4 hour prestorage of the whole blood unit prior to centrifugation strongly decreases the activation of platelets upon stimuli and results in platelet concentrates much more stable to storage. PMID:3070889

  15. Partial purification of the 5-hydroxytryptophan-reuptake system from human blood platelets using a citalopram-derived affinity resin

    Energy Technology Data Exchange (ETDEWEB)

    Biessen, E.A.L; Horn, A.S.; Robillard, G.T. (Univ. of Groningen (Netherlands))

    1990-04-03

    This paper describes a procedure for the synthesis and application of a citalopram-derived affinity resin in purifying the 5HT-reuptake system from human blood platelets. A two-step scheme has been developed for partial purification, based on wheat germ agglutinin-lectin (WGA) affinity and citalopram affinity chromatographies. Upon solubilization of the carrier with 1% digitonin, a 50-70-fold increase in specific ({sup 3}H) imipramine binding activity with a 70% recovery could be accomplished through WGA-lectin chromatography. The WGA pool was then subjected to affinity chromatography on citalopram-agarose. At least 90% of the binding capacity adsorbed to the column. Specific elution using 10 {mu}M citalopram resulted in a 22% recovery of binding activity. A 10,000-fold overall purification was obtained by using this two-step procedure. Analysis of the fractions on SDS-PAGE after {sup 125}I labeling revealed specific elution of 78- and 55-kDa proteins concomitant with the appearance of ({sup 3}H) imipramine binding activity. The pharmacological profile of the partially purified reuptake system correlated well with that derived from the crude membrane-bound reuptake system, suggesting a copurification of the 5HT binding activity and ({sup 3}H)imipramine binding activity.

  16. Comparative morphology analysis of live blood platelets using scanning ion conductance and robotic dark-field microscopy.

    Science.gov (United States)

    Kraus, Max-Joseph; Seifert, Jan; Strasser, Erwin F; Gawaz, Meinrad; Schäffer, Tilman E; Rheinlaender, Johannes

    2016-09-01

    Many conventional microscopy techniques for investigating platelet morphology such as electron or fluorescence microscopy require highly invasive treatment of the platelets such as fixation, drying and metal coating or staining. Here, we present two unique but entirely different microscopy techniques for direct morphology analysis of live, unstained platelets: scanning ion conductance microscopy (SICM) and robotic dark-field microscopy (RDM). We demonstrate that both techniques allow for a quantitative evaluation of the morphological features of live adherent platelets. We show that their morphology can be quantified by both techniques using the same geometric parameters and therefore can be directly compared. By imaging the same identical platelets subsequently with SICM and RDM, we found that area, perimeter and circularity of the platelets are directly correlated between SICM and dark-field microscopy (DM), while the fractal dimension (FD) differed between the two microscopy techniques. We show that SICM and RDM are both valuable tools for the ex vivo investigation of the morphology of live platelets, which might contribute to new insights into the physiological and pathophysiological role of platelet spreading. PMID:27063564

  17. Post-irradiation changes in acetylcholinesterase and butyrylcholinesterase activity in blood platelets of whole-body irradiated rats

    International Nuclear Information System (INIS)

    After 24, 96 and 144 hours following whole-body irradiation of rats with 8 Gy an increased acetylcholinesterase activity was found in platelets. The activity of butyrylcholinesterase in platelets increased in all investigated intervals after whole-body irradiation of rats with 8 Gy. The highest values were recorded after 144, 192 and 264 hours. (author)

  18. Changes in platelet function, blood coagulation and fibrinolysis during insulin-induced hypoglycaemia in juvenile diabetics and normal subjects

    DEFF Research Database (Denmark)

    Dalsgaard-Nielsen, J; Madsbad, S; Hilsted, J

    1982-01-01

    patients were normoglycaemic for at least 10 hr before the study. Platelet aggregation in vitro was induced by lower adenosine diphosphate (ADP) concentrations in the diabetics than in the controls before hypoglycaemia and 0 and 60 min after insulin infusion. Platelet counts decreased significantly in the...

  19. A Study on the radiation effects for the function and structure of rabbit blood platelets in various dose rates

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Kohichi (Nippon Dental Univ., Tokyo (Japan))

    1991-12-01

    Mature peripheral platelets in rabbits were irradiated with a total 10 Gy of {sup 60}Co-{gamma} rays at the average dose rates of 0.2, 0.5, 1.0, 1.5 and 1.7 Gy/min. The effects was evaluated from the functional aspect by determining the ability of platelets to aggregate and replease, and the metabolic aspect by examining the kinetics of prostaglandin in platelets. In addition, platelet structure was compared using an electron microscope. The ability of platelets to aggregate and release was accelerated in all irradiated groups, compared with a non-irradiated group, especially in groups with average dose rates of 0.5 Gy/min and 1.0 Gy/min. The amount of MDA, a final product of prostaglandin in platelets, increased in all irradiated groups in comparison with the non-irradiated group, especially in the 0.5 Gy/min, 1.0 Gy/min and 1.5 Gy/min groups. Observation with a scanning electron microscope revealed a clear rock-like appearance of the surface of aggregates of platelets and a larger number of pseudopodia with longer projections in the 1.0 Gy/min group than in the non-irradiated group. Moreover, the surfaces of the aggregates in the 1.7 Gy/min group, but the adhension between psudopodia of the platelet aggregates was weaker than that of 1.0 Gy/min group. In observation with a transmission electron microscope, dense bodies that released their contents were noticed in platelet aggregates, and a stenopeic appearance between psudopodia and between platelets, and density aggregated platelets were observed in the 1.0 Gy/min irradiated group. Vacuolation of granules in platelets was more marked in aggregates of 1.7 Gy/min group than in that of the non-irradiated group, and large numbers of platelets with uneven surfaces were observed. Therefore, the effects of dose rates were found to be closely related to changes in structures, as well as to the inner function of platelets. (author).

  20. A Study on the radiation effects for the function and structure of rabbit blood platelets in various dose rates

    International Nuclear Information System (INIS)

    Mature peripheral platelets in rabbits were irradiated with a total 10 Gy of 60Co-γ rays at the average dose rates of 0.2, 0.5, 1.0, 1.5 and 1.7 Gy/min. The effects was evaluated from the functional aspect by determining the ability of platelets to aggregate and replease, and the metabolic aspect by examining the kinetics of prostaglandin in platelets. In addition, platelet structure was compared using an electron microscope. The ability of platelets to aggregate and release was accelerated in all irradiated groups, compared with a non-irradiated group, especially in groups with average dose rates of 0.5 Gy/min and 1.0 Gy/min. The amount of MDA, a final product of prostaglandin in platelets, increased in all irradiated groups in comparison with the non-irradiated group, especially in the 0.5 Gy/min, 1.0 Gy/min and 1.5 Gy/min groups. Observation with a scanning electron microscope revealed a clear rock-like appearance of the surface of aggregates of platelets and a larger number of pseudopodia with longer projections in the 1.0 Gy/min group than in the non-irradiated group. Moreover, the surfaces of the aggregates in the 1.7 Gy/min group, but the adhension between psudopodia of the platelet aggregates was weaker than that of 1.0 Gy/min group. In observation with a transmission electron microscope, dense bodies that released their contents were noticed in platelet aggregates, and a stenopeic appearance between psudopodia and between platelets, and density aggregated platelets were observed in the 1.0 Gy/min irradiated group. Vacuolation of granules in platelets was more marked in aggregates of 1.7 Gy/min group than in that of the non-irradiated group, and large numbers of platelets with uneven surfaces were observed. Therefore, the effects of dose rates were found to be closely related to changes in structures, as well as to the inner function of platelets. (author)

  1. Function, expression and localization of annexin A7 in platelets and red blood cells: Insights derived from an annexin A7 mutant mouse

    Directory of Open Access Journals (Sweden)

    Zamparelli Carlotta

    2003-08-01

    Full Text Available Abstract Background Annexin A7 is a Ca2+- and phospholipid-binding protein expressed as a 47 and 51 kDa isoform, which is thought to be involved in membrane fusion processes. Recently the 47 kDa isoform has been identified in erythrocytes where it was proposed to be a key component in the process of the Ca2+-dependent vesicle release, a process with which red blood cells might protect themselves against an attack by for example complement components. Results The role of annexin A7 in red blood cells was addressed in erythrocytes from anxA7-/- mice. Interestingly, the Ca2+-mediated vesiculation process was not impaired. Also, the membrane organization appeared not to be disturbed as assessed using gradient fractionation studies. Instead, lack of annexin A7 led to an altered cell shape and increased osmotic resistance of red blood cells. Annexin A7 was also identified in platelets. In these cells its loss led to a slightly slower aggregation velocity which seems to be compensated by an increased number of platelets. The results appear to rule out an important role of annexin A7 in membrane fusion processes occurring in red blood cells. Instead the protein might be involved in the organization of the membrane cytoskeleton. Red blood cells may represent an appropriate model to study the role of annexin A7 in cellular processes. Conclusion We have demonstrated the presence of both annexin A7 isoforms in red blood cells and the presence of the small isoform in platelets. In both cell types the loss of annexin A7 impairs cellular functions. The defects observed are however not compatible with a crucial role for annexin A7 in membrane fusion processes in these cell types.

  2. Subpopulations in purified platelets adhering on glass.

    Science.gov (United States)

    Donati, Alessia; Gupta, Swati; Reviakine, Ilya

    2016-01-01

    Understanding how platelet activation is regulated is important in the context of cardiovascular disorders and their management with antiplatelet therapy. Recent evidence points to different platelet subpopulations performing different functions. In particular, procoagulant and aggregating subpopulations have been reported in the literature in platelets treated with the GPVI agonists. How the formation of platelet subpopulations upon activation is regulated remains unclear. Here, it is shown that procoagulant and aggregating platelet subpopulations arise spontaneously upon adhesion of purified platelets on clean glass surfaces. Calcium ionophore treatment of the adhering platelets resulted in one platelet population expressing both the procoagulant and the adherent population markers phosphatidylserine and the activated form of GPIIb/IIIa, while all of the platelets expressed CD62P independently of the ionophore treatment. Therefore, all platelets have the capacity to express all three activation markers. It is concluded that platelet subpopulations observed in various studies reflect the dynamics of the platelet activation process. PMID:27338300

  3. Oral streptococci utilize a Siglec-like domain of serine-rich repeat adhesins to preferentially target platelet sialoglycans in human blood.

    Directory of Open Access Journals (Sweden)

    Lingquan Deng

    2014-12-01

    Full Text Available Damaged cardiac valves attract blood-borne bacteria, and infective endocarditis is often caused by viridans group streptococci. While such bacteria use multiple adhesins to maintain their normal oral commensal state, recognition of platelet sialoglycans provides an intermediary for binding to damaged valvular endocardium. We use a customized sialoglycan microarray to explore the varied binding properties of phylogenetically related serine-rich repeat adhesins, the GspB, Hsa, and SrpA homologs from Streptococcus gordonii and Streptococcus sanguinis species, which belong to a highly conserved family of glycoproteins that contribute to virulence for a broad range of Gram-positive pathogens. Binding profiles of recombinant soluble homologs containing novel sialic acid-recognizing Siglec-like domains correlate well with binding of corresponding whole bacteria to arrays. These bacteria show multiple modes of glycan, protein, or divalent cation-dependent binding to synthetic glycoconjugates and isolated glycoproteins in vitro. However, endogenous asialoglycan-recognizing clearance receptors are known to ensure that only fully sialylated glycans dominate in the endovascular system, wherein we find these particular streptococci become primarily dependent on their Siglec-like adhesins for glycan-mediated recognition events. Remarkably, despite an excess of alternate sialoglycan ligands in cellular and soluble blood components, these adhesins selectively target intact bacteria to sialylated ligands on platelets, within human whole blood. These preferred interactions are inhibited by corresponding recombinant soluble adhesins, which also preferentially recognize platelets. Our data indicate that circulating platelets may act as inadvertent Trojan horse carriers of oral streptococci to the site of damaged endocardium, and provide an explanation why it is that among innumerable microbes that gain occasional access to the bloodstream, certain viridans group

  4. Evaluation of Platelet and Red Blood Cell Parameters with Proposal of Modified Score as Discriminating Guide for Iron Deficiency Anemia and β-Thalassemia Minor

    Science.gov (United States)

    Shrivastava, Vikas; Chandra, Smita; Rawat, Anil; Nautiyal, Ruchira

    2016-01-01

    Introduction Iron Deficiency Anaemia (IDA) and β-Thalassaemia Minor (BTM) are considered to be important cause of microcytic hypochromic anaemia. Studies have evaluated various red cell parameters which are easily available on electronic cell counters for discrimination of IDA and BTM in different ethnic populations. The analysis of previously established red cell discriminative indices with new cut-off have also been done by studies which may be relevant in their set of population for differentiation. Aim The study was conducted to propose a modified score considering the established red blood cell indices with a new cut off and to formulate index taking into consideration Red Blood Cell (RBC) and platelet parameters for early differentiation of IDA and BTM. Materials and Methods The prospective study included cases with MCV< 80 fl and new modified score of 11 was proposed by statistically analysing the previous discriminative indices with new cut-off by giving score 0 for IDA and score 1 for BTM. The summation of all scores gave modified 11 T score. A new cut off for differentiation of IDA and BTM was proposed in the study by using ROC curve and analysing AUC which statistically corresponded to highest accuracy. An attempt to formulate a new index using the RBC and platelet parameters was also made for initial discrimination. Results The study included 153 cases and in addition to red blood cell parameters, mean platelet volume and platelet distribution width also showed statistical significant difference between IDA and BTM (p<0.05). Modified new 11 T score was 87.6% specific for BTM while proposed index showed 80.4% negative predictive value for BTM and correctly identified 75% of cases. Conclusion The proposed new index and modified 11T score may be used for initial discrimination of BTM and IDA especially in resource limited regions. Apart from RBC parameters, mean platelet volume and platelet distribution width may also be useful in early differentiation

  5. Activated tumor cell integrin αvβ3 cooperates with platelets to promote extravasation and metastasis from the blood stream.

    Science.gov (United States)

    Weber, Martin R; Zuka, Masahiko; Lorger, Mihaela; Tschan, Mario; Torbett, Bruce E; Zijlstra, Andries; Quigley, James P; Staflin, Karin; Eliceiri, Brian P; Krueger, Joseph S; Marchese, Patrizia; Ruggeri, Zaverio M; Felding, Brunhilde H

    2016-04-01

    Metastasis is the main cause of death in cancer patients, and understanding mechanisms that control tumor cell dissemination may lead to improved therapy. Tumor cell adhesion receptors contribute to cancer spreading. We noted earlier that tumor cells can expressing the adhesion receptor integrin αvβ3 in distinct states of activation, and found that cells which metastasize from the blood stream express it in a constitutively high affinity form. Here, we analyzed steps of the metastatic cascade in vivo and asked, when and how the affinity state of integrin αvβ3 confers a critical advantage to cancer spreading. Following tumor cells by real time PCR, non-invasive bioluminescence imaging, intravital microscopy and histology allowed us to identify tumor cell extravasation from the blood stream as a rate-limiting step supported by high affinity αvβ3. Successful transendothelial migration depended on cooperation between tumor cells and platelets involving the high affinity tumor cell integrin and release of platelet granules. Thus, this study identifies the high affinity conformer of integrin αvβ3 and its interaction with platelets as critical for early steps during hematogenous metastasis and target for prevention of metastatic disease. PMID:27067975

  6. Activated platelet supernatant can augment the angiogenic potential of human peripheral blood stem cells mobilized from bone marrow by G-CSF.

    Science.gov (United States)

    Kang, Jeehoon; Hur, Jin; Kang, Jin-A; Yun, Ji-Yeon; Choi, Jae-Il; Ko, Seung Bum; Lee, Choon-Soo; Lee, Jaewon; Han, Jung-Kyu; Kim, Hyun Kyung; Kim, Hyo-Soo

    2014-10-01

    Platelets not only play a role in hemostasis, but they also promote angiogenesis and tissue recovery by releasing various cytokines and making an angiogenic milieu. Here, we examined autologous 'activated platelet supernatant (APS)' as a priming agent for stem cells; thereby enhance their pro-angiogenic potential and efficacy of stem cell-based therapy for ischemic diseases. The mobilized peripheral blood stem cells ((mob)PBSCs) were isolated from healthy volunteers after subcutaneous injection of granulocyte-colony stimulating factor. APS was collected separately from the platelet rich plasma after activation by thrombin. (mob)PBSCs were primed for 6h before analysis. Compared to naive platelet supernatants, APS had a higher level of various cytokines, such as IL8, IL17, PDGF and VEGF. APS-priming for 6h induced (mob)PBSCs to express key angiogenic factors, surface markers (i.e. CD34, CD31, and CXCR4) and integrins (integrins α5, β1 and β2). Also (mob)PBSCs were polarized toward CD14(++)/CD16(+) pro-angiogenic monocytes. The priming effect was reproduced by an in vitro reconstruction of APS. Through this phenotype, APS-priming increased cell-cell adhesion and cell-extracellular matrix adhesion. The culture supernatant of APS-primed (mob)PBSCs contained high levels of IL8, IL10, IL17 and TNFα, and augmented proliferation and capillary network formation of human umbilical vein endothelial cells. In vivo transplantation of APS-primed (mob)PBSCs into athymic mice ischemic hindlimbs and Matrigel plugs elicited vessel differentiation and tissue repair. In safety analysis, platelet activity increased after mixing with (mob)PBSCs regardless of priming, which was normalized by aspirin treatment. Collectively, our data identify that APS-priming can enhance the angiogenic potential of (mob)PBSCs, which can be used as an adjunctive strategy to improve the efficacy of cell therapy for ischemic diseases. PMID:25016235

  7. Fluoxetine in panic disorder: pharmacologic and tritiated platelet imipramine and paroxetine binding study.

    OpenAIRE

    Pecknold, J C; Luthe, L; Iny, L; Ramdoyal, D

    1995-01-01

    Serotonergic implication in panic disorder has been demonstrated by the efficacy of serotonin reuptake blockers in treatment. Fluoxetine, a potent 5-HT reuptake blocker, has been suggested to have anti-panic efficacy. This open study examines 30 patients (eight males and 22 females) with an average age of 36.9 years, ranging from 18 to 62, who were treated for eight weeks with fluoxetine (mean dose 20 mg per day). All patients fulfilled DSM-III-R criteria of panic disorder with agoraphobia as...

  8. Platelet function in dogs

    DEFF Research Database (Denmark)

    Nielsen, Line A.; Zois, Nora Elisabeth; Pedersen, Henrik D.;

    2007-01-01

    Background: Clinical studies investigating platelet function in dogs have had conflicting results that may be caused by normal physiologic variation in platelet response to agonists. Objectives: The objective of this study was to investigate platelet function in clinically healthy dogs of 4...... different breeds by whole-blood aggregometry and with a point-of-care platelet function analyzer (PFA-100), and to evaluate the effect of acetylsalicylic acid (ASA) administration on the results from both methods. Methods: Forty-five clinically healthy dogs (12 Cavalier King Charles Spaniels [CKCS], 12...... the methodology applied. However, the importance of these breed differences remains to be investigated. The PFA-100 method with Col + Epi as agonists, and ADP-induced platelet aggregation appear to be sensitive to ASA in dogs....

  9. A Case of Late Stent Thrombosis Following Platelet Transfusion in a Patient With Aplastic Anemia

    OpenAIRE

    Shin, Hyun-Sung; Kang, Tae Soo

    2012-01-01

    Aplastic anemia is a condition in which the bone marrow fails to produce adequate numbers of peripheral blood elements. The incidences of atherosclerosis and myocardial infarction in patients with congenital coagulation disorders and chronic thrombocytopenia are very low. In this paper, a case of late stent thrombosis within a drug-eluting stent occurring after platelet transfusion in a patient with aplastic anemia is presented. The authors' observations emphasize the risks of platelet transf...

  10. Generation of superoxide anion radicals and platelet glutathione peroxidase activity in patients with schizophrenia

    OpenAIRE

    Dietrich-Muszalska A; Kwiatkowska A.

    2014-01-01

    Anna Dietrich-Muszalska, Anna KwiatkowskaDepartment of Biological Psychiatry of the Chair of Experimental and Clinical Physiology, Medical University of Lodz, Lodz, PolandAbstract: Blood platelets are considered to be a peripheral marker in schizophrenia and other psychiatric disorders. Oxidative stress in schizophrenia may be responsible for changes in platelet metabolism and function; therefore, the aim of this study was to examine and compare the generation of superoxide anions and activit...

  11. Ethyl Acetate Extract from Tissue-Cultured Mountain Ginseng Adventitious Roots Inhibits In Vitro Platelet Aggregation in Whole Human Blood and Augments Peripheral Blood Flow in Mice

    OpenAIRE

    Lee, In Sun; Kim, Seul-Ki; Jeon, Min Hwa; Jeon, Won Kyung

    2011-01-01

    We previously reported that in vitro anti-platelet activity of tissue-cultured mountain ginseng (TCMG) ethanol extracts show improved efficacy when compared with commercial ginseng products such as Korean red ginseng and Panax ginseng. However, information on the anti-platelet activity of the ethyl acetate fraction from TCMG adventitious roots is limited. Therefore, in this study, we further investigated the effects of an ethyl acetate extract of TCMG (EA-TCMG) adventitious roots on in vitro ...

  12. A randomized trial of washed red blood cell and platelet transfusions in adult acute leukemia [ISRCTN76536440

    Directory of Open Access Journals (Sweden)

    Rowe Jacob M

    2004-12-01

    Full Text Available Abstract Background Platelet transfusion is universally employed in acute leukemia. Platelet concentrate supernatants contain high concentrations of biologic mediators that might impair immunity. We investigated whether washed platelet and red cell transfusions could improve clinical outcomes in adult patients with acute leukemia. Methods A pilot randomized trial of washed, leukoreduced ABO identical transfusions versus leukoreduced ABO identical transfusions was conducted in 43 adult patients with acute myeloid or lymphoid leukemia during 1991–94. Primary endpoints to be evaluated were platelet transfusion refractoriness, infectious and bleeding complications and overall survival. Results There were no significant differences in infectious or major bleeding complications and only one patient required HLA matched platelet transfusions. Minor bleeding was more frequent in the washed, leukoreduced arm of the study. Confirmed transfusion reactions were more frequent in the leukoreduced arm of the study. Overall survival was superior in the washed arm of the study (40% versus 22% at 5 years, but this difference was not statistically significant (p = 0.36. A planned subset analysis of those ≤50 years of age found that those in the washed, leukoreduced arm (n = 12 had a 75% survival at five years compared with 30% in the leukoreduced arm (n = 10 (p = 0.037 Conclusion This study provides the first evidence concerning the safety and efficacy of washed platelets, and also raises the possibility of improved survival. We speculate that transfusion of stored red cell and platelet supernatant may compromise treatment, particularly in younger patients with curable disease. Larger trials will be needed to assess this hypothesis.

  13. Platelet activation and platelet-leukocyte interaction in dogs naturally infected with Babesia rossi.

    Science.gov (United States)

    Goddard, Amelia; Leisewitz, Andrew L; Kristensen, Annemarie T; Schoeman, Johan P

    2015-09-01

    Using flow cytometry, platelet-leukocyte aggregate (PLA) formation has previously been documented in dogs with a variety of systemic inflammatory disorders and immune-mediated haemolytic anaemia. Platelet activation and subsequent interaction between platelets and leukocytes are important for regulating innate immunity and systemic inflammation. The objective of this study was to investigate PLA formation in canine babesiosis and to determine whether it was associated with outcome. Blood was collected from 36 client-owned dogs diagnosed with Babesia rossi infection and 15 healthy controls using EDTA as anticoagulant. Activated platelets and PLA formation were detected by measuring surface expression of P-selectin (CD62P) on platelets, monocytes and neutrophils. Of the Babesia-infected dogs, 29 survived and seven died. The percentage of CD62P-positive monocytes was significantly higher (P = 0.036) in the Babesia-infected dogs (54%) than in healthy control dogs (35.3%). However, there were no significant differences between the Babesia-infected and control groups for CD62P-positive platelets (4.9% and 1.2%, respectively) and CD62P-positive neutrophils (28.3% and 17.9%, respectively). The percentage of CD62P-positive monocytes was significantly higher (P = 0.019) in the survivors (58.9%) than in healthy control dogs; however, there were no significant differences between the non-survivors (39.2%) and the controls or between survivors and non-survivors. There were no significant differences between groups for the percentage of CD62P-positive platelets (survivors 4.8%; non-survivors 5.3%; controls 1.2%) or CD62P-positive neutrophils (survivors 31.6%; non-survivors 5.6%; controls 17.9%). In conclusion, Babesia-infected dogs, specifically dogs that survived, had a significantly increased percentage of platelet-monocyte aggregates compared to healthy control dogs. PMID:26088270

  14. Effect of Continuous Positive Airway Pressure Ventilation on Platelet-activating Factor and Blood Coagulation Function in Patients with Obstructive Sleep Apnea-hypopnea Syndrome

    International Nuclear Information System (INIS)

    To investigate the effect of continuous positive airway pressure ventilation (CPAP) on platelet-activating factor (PAF) expression and blood coagulation function in patients with obstructive sleep apnea-hypopnea syndrome (OSAS), the blood sample of 40 patients with OSAS were taken before treatment and on the day 30 after treatment respectively. PAF, thromboxane B2 (TXB2), prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrin(FIB) in patients and 37 health controls were detected. The results showed that PAF, TXB2, FIB in OSAS patients before treatment were significantly higher than those of after treatment and control group (P0.05). There were abnormal expression of PAF and hypercoagulability in OSAS patients. CPAP could effectively decrease the expression of PAF, TXB2 and could also correct dysfunction of blood coagulation. It had certain effect in lightening the clinical symptoms in OSAS patients. (authors)

  15. Platelet bioreactor-on-a-chip

    OpenAIRE

    Thon, Jonathan N.; Mazutis, Linas; Wu, Stephen; Sylman, Joanna L.; Ehrlicher, Allen; Machlus, Kellie R.; Feng, Qiang; Lu, Shijiang; Lanza, Robert; Neeves, Keith B.; Weitz, David A; Italiano, Joseph E.

    2014-01-01

    We have developed a biomimetic microfluidic platelet bioreactor that recapitulates bone marrow and blood vessel microenvironments.Application of shear stress in this bioreactor triggers physiological proplatelet production, and platelet release.

  16. Platelet activation and aggregation

    DEFF Research Database (Denmark)

    Jensen, Maria Sander; Larsen, O H; Christiansen, Kirsten; Fenger-Eriksen, C; Ingerslev, J; Sørensen, Benny

    2013-01-01

    This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated...... by tissue factor evaluated by means of impedance aggregometry. Citrated whole blood from healthy volunteers and haemophilia A patients with the addition of inhibitors of the contact pathway and fibrin polymerization was evaluated. In healthy persons, a second wave of platelet aggregation was found to...... coincide with the thrombin burst and to be abolished by thrombin inhibitors. In this system, platelet aggregation in severe haemophilia A (n = 10) was found to be significantly decreased as compared with healthy individuals (912 ± 294 vs. 1917 ± 793 AU × min, P = 0.003), most probably due to the weak level...

  17. Glycine reduces platelet aggregation

    OpenAIRE

    Schemmer, Peter; Zhong, Zhi; Galli, Uwe; Wheeler, Michael D.; Xiangli, Li; Bradford, Blair U.; Conzelmann, Lars O.; Forman, Dow; Boyer, José; Thurman, Ronald G

    2012-01-01

    It has been demonstrated that a wide variety of white blood cells and macrophages (i.e. Kupffer cells, alveolar and peritoneal macrophages and neutrophils) contain glycine-gated chloride channels. Binding of glycine on the receptor stimulates Cl− influx causing membrane hyperpolarization that prevents agonist-induced influx of calcium. Since platelet-aggregation is calcium-dependent, this study was designed to test the hypothesis that glycine would inhibit platelet aggregation. Rats were fed ...

  18. Extracting Biological Meaning From Global Proteomic Data on Circulating-Blood Platelets: Effects of Diabetes and Storage Time

    Energy Technology Data Exchange (ETDEWEB)

    Miller, John H.; Suleiman, Atef; Daly, Don S.; Springer, David L.; Spinelli, Sherry L.; Blumberg, Neil; Phipps, Richard P.

    2008-11-25

    Transfusion of platelets into patients suffering from trauma and a variety of disease is a common medical practice that involves millions of units per year. Partial activation of platelets can result in the release of bioactive proteins and lipid mediators that increase the risk of adverse post-transfusion effects. Type-2 diabetes and storage are two factors known to cause partial activation of platelets. A global proteomic study was undertaken to investigate these effects. In this paper we discuss the methods used to interpret these data in terms of biological processes affected by diabetes and storage. The main emphasis is on the processing of proteomic data for gene ontology enrichment analysis by techniques originally designed for microarray data.

  19. Approaches to synthetic platelet analogs.

    Science.gov (United States)

    Modery-Pawlowski, Christa L; Tian, Lewis L; Pan, Victor; McCrae, Keith R; Mitragotri, Samir; Sen Gupta, Anirban

    2013-01-01

    Platelet transfusion is routinely used for treating bleeding complications in patients with hematologic or oncologic clotting disorders, chemo/radiotherapy-induced myelosuppression, trauma and surgery. Currently, these transfusions mostly use allogeneic platelet concentrates, while products like lyophilized platelets, cold-stored platelets and infusible platelet membranes are under investigation. These natural platelet-based products pose considerable risks of contamination, resulting in short shelf-life (3-5 days). Recent advances in pathogen reduction technologies have increased shelf-life to ~7 days. Furthermore, natural platelets are short in supply and also cause several biological side effects. Hence, there is significant clinical interest in platelet-mimetic synthetic analogs that can allow long storage-life and minimum side effects. Accordingly, several designs have been studied which decorate synthetic particles with motifs that promote platelet-mimetic adhesion or aggregation. Recent refinement in this design involves combining the adhesion and aggregation functionalities on a single particle platform. Further refinement is being focused on constructing particles that also mimic natural platelet's shape, size and elasticity, to influence margination and wall-interaction. The optimum design of a synthetic platelet analog would require efficient integration of platelet's physico-mechanical properties and biological functionalities. We present a comprehensive review of these approaches and provide our opinion regarding the future directions of this research. PMID:23092864

  20. Changes in blood platelet aggregation in two leukaemic patients after receiving large dose of γ-irradiation

    International Nuclear Information System (INIS)

    This paper presents the results of platelet aggregation determination in two patients with leukaemia after irradiation with large doses of γ-rays. It is shown that in the early days after irradiation an increase of aggregation response appeared. Perhaps it is one of the causes of post-irradiation microcirculatory disturbances. We are inclined to say that the inhibition of platelet aggregation during early days after irradiation would be helpful to alleviate microcirculatory disturbances, thereby the repair of radiation damage might be brought about

  1. Effects of bemiparin and heparin on blood pressure, renal and liver function tests and platelet indices of salt-loaded uninephrectomized rats

    Directory of Open Access Journals (Sweden)

    K. Dizaye

    2011-01-01

    Full Text Available Low-molecular-weight Heparins (LMWHs are being preferred to unfractionated Heparin (UFH because of their superior convenience and comparable or slightly better toxicity profile. This study was designed to investigate and compare the effects of LMWH (Bemiparin and Heparin on hemodynamic parameters, liver and renal function tests and platelet indices of salt-loaded uninephrectomized hypertensive rats. The experimental rats divided into two groups. The first group included 18 hypertensive rats. Hypertension induced by unilateral nephrectomy and high NaCl loading with 4% NaCl in diet for 4 weeks. The rat models were subdivided into three groups, each subgroup consists of six rats. The first subgroup served as a positive control. The second subgroup received a daily intraperitoneal (I.P injection (250 unit/kg of Bemiparin for thirty days. The third sub group received daily I.P injection (250 unit/kg of Heparin for thirty days. The second group included six rats underwent sham operated surgery and served as a control group. Blood pressure was recorded in conscious rats by the tail-cuff plethmography method. At the end of the experiments, blood samples were collected from the rats for determination of serum creatinine, blood urea nitrogen, serum total bilirubin, serum sodium, potassium, calcium, aspartate aminotransferase (AST, alanine aminotransferase (ALT, alkaline phosphatase (ALP concentrations and platelet indices. Compared to sham control rats, Systolic blood pressure in uninephrectomized loaded with a high salt was significantly reduced by administration of both Bemiparin and Heparin. Serum K+ and Na+ levels of hypertensive rats were significantly increased. Bemiparin significantly lowered serum K+ and Na+ levels of uninephrectomized rats, while Heparin did not change serum K+ and Na+ levels. The rise in both blood urea and serum creatinine of salt-loaded uninephrectomized hypertensive rats were significantly (P<0.05 reduced by Bemiparin and

  2. Kinetic behaviour of 111-indium-oxine-labeled platelets in vivo. Study in volunteers with normal hematological findings and patients showing disturbed platelet turnover

    International Nuclear Information System (INIS)

    A method designed to label platelets with 111-In-oxine was investigated in volunteers with normal hematological findings and patients showing disturbed platelet turnover with particular account being taken of the following aspects: Suitability of the method to label blood taken up in special rubber bags in order to improve platelet recovery in the presence of thrombopenia and to ensure greater sterility; simplicity of blood sample processing to determine survival time; behaviour of the platelets in the organism of individuals with normal cell counts and value of determinations of platelet survival time and site of degradation in patients showing disturbed platelet turnover both from the diagnostic point of view and with regard to the possible therapeutic consequences to be drawn (splenectomy). The investigations revealed an average labeling rate of 24.9% for blood samples from healthy volunteers drawn up in rubber bags; the recovery rate was determined to be in the order of 43.2%. Our findings confirmed that an accurate diagnosis of thrombopenic disorders can be established on the basis of survival time curves plotted from the whole blood samples and also pointed to considerably longer survival times as compared to those determined for processed platelet concentrates. The time course of activity in liver and spleen was assessed by means of an Anger camera. The method of labeling blood collected in rubber bags was found to be particularly suitable for patients showing disturbed platelet turnover. Pathological degradation processes can be detected by functional measurements using special detectors. In cases where the organ activity curves obtained are difficult to interpret it may help to subtract the proportion of activity that is attributable to the circulating blood. (TRV)

  3. Kinetics of 3H-serotonin uptake by platelets in infantile autism and developmental language disorder (including five pairs of twins)

    Energy Technology Data Exchange (ETDEWEB)

    Katsui, T.; Okuda, M.; Usuda, S.; Koizumi, T.

    1986-03-01

    The kinetics of 5-HT uptake by platelets was studied in cases of infantile autism and developmental language disorder (DLD) and normal subjects. Two patients of the autism group were twins, and the seven patients of the DLD group were members of four pairs of twins. The Vmax values (means +/- SD) for autism and DLD were 6.46 +/- .90 pmol 5-HT/10(7) cells/min and 4.85 +/- 1.50 pmol 5-HT/10(7) cells/min, respectively. These values were both significantly higher than that of 2.25 +/- .97 pmole 5-HT/10(7) cells/min for normal children. The Km values of the three groups were not significantly different. Data on the five pairs of twins examined suggested that the elevated Vmax of 5-HT uptake by platelets was determined genetically.

  4. Kinetics of 3H-serotonin uptake by platelets in infantile autism and developmental language disorder (including five pairs of twins)

    International Nuclear Information System (INIS)

    The kinetics of 5-HT uptake by platelets was studied in cases of infantile autism and developmental language disorder (DLD) and normal subjects. Two patients of the autism group were twins, and the seven patients of the DLD group were members of four pairs of twins. The Vmax values (means +/- SD) for autism and DLD were 6.46 +/- .90 pmol 5-HT/10(7) cells/min and 4.85 +/- 1.50 pmol 5-HT/10(7) cells/min, respectively. These values were both significantly higher than that of 2.25 +/- .97 pmole 5-HT/10(7) cells/min for normal children. The Km values of the three groups were not significantly different. Data on the five pairs of twins examined suggested that the elevated Vmax of 5-HT uptake by platelets was determined genetically

  5. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    OpenAIRE

    Gupta, Ashish; Chandra, Tulika; Kumar, Ashutosh

    2011-01-01

    Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. The present study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, CSM Medical University, Lucknow. Random donor platelets were prepared by platelet rich plasma method. Whole blood (350 ml) was collected in antic...

  6. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    OpenAIRE

    Gupta, Ashish; Chandra, Tulika; Kumar, Ashutosh

    2011-01-01

    Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. This study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, C S M Medical University, Lucknow. Random donor platelets were prepared by the platelet-rich plasma method. Whole blood (350 ml) was collected in antico...

  7. Sports medicine and platelet-rich plasma: nonsurgical therapy.

    Science.gov (United States)

    Grambart, Sean T

    2015-01-01

    A Cochrane Review was performed to assess the effects of platelet-rich therapies for treating musculoskeletal soft tissue injuries. Selection criteria were randomized and quasirandomized controlled trials (RCTs) that compared platelet-rich therapy with either placebo, autologous whole blood, dry needling, or no platelet-rich therapy for people with acute or chronic musculoskeletal soft tissue injuries. Primary outcomes were functional status, pain, and adverse effects. The investigators found 19 studies that compared platelet-rich therapy with placebo, autologous whole blood, dry needling, or no platelet-rich therapy. Disorders included rotator cuff tears (arthroscopic repair; 6 trials); shoulder impingement syndrome surgery (1 trial); elbow epicondylitis (3 trials); anterior cruciate ligament (ACL) reconstruction (4 trials), ACL reconstruction (donor graft site application; 2 trials), patellar tendinopathy (1 trial), Achilles tendinopathy (1 trial), and acute Achilles rupture surgical repair (1 trial). They further subdivided the studies based on type of treatment, including tendinopathies in which platelet-rich therapy injections were the main treatment (5 trials), and surgical augmentation procedures in which platelet-rich therapy was applied during surgery (14 trials). The conclusion was that there is currently insufficient evidence to support the use of platelet-rich therapy for treating musculoskeletal soft tissue injuries. Researchers contemplating RCTs should consider the coverage of currently ongoing trials when assessing the need for future RCTs on specific conditions. There is a need for standardization of PRP preparation methods. At this time, the use of PRP in foot and ankle surgery as an orthobiologic does not have an absolute indication. Many of the studies are lower evidence-based from surgical techniques. Several in vitro studies have shown that growth factors promote the regeneration of bone, cartilage, and tendons. More clinical studies are

  8. Platelet alloimmunization after transfusion

    DEFF Research Database (Denmark)

    Taaning, E; Simonsen, A C; Hjelms, E;

    1997-01-01

    (17.9%), of whom 18 (15.4%) had had no detectable antibodies before transfusion. There was a positive correlation between the transfused load of immunogenic materials and the frequency of alloimmunization against HLA antigens. In one third of the immunized patients, there was no history of previous......BACKGROUND AND OBJECTIVES: The frequency of platelet-specific antibodies after one series of blood transfusions has not been reported, and in multiply transfused patients is controversial. MATERIALS AND METHODS: We studied the frequency of alloimmunization against platelet antigens in 117 patients......-antibody-specific immobilization of platelet antigen assay. HLA antibodies were detected by the standard lymphocyte cytotoxicity techniques. RESULTS: We found platelet-specific anti-HPA-5b (anti-Bra) in 2 cases (1.7%). One antibody was the result of de novo immunization. We detected lymphocytotoxic HLA antibodies in 21 patients...

  9. Treatment of Anxiety Disorders and Comorbid Alcohol Abuse with Buspirone in a Patient with Antidepressant-Induced Platelet Dysfunction: A Case Report

    Directory of Open Access Journals (Sweden)

    Mir Mazhar

    2013-01-01

    Full Text Available The risk of abnormal bleeding with serotonin reuptake inhibitors has been known, but there is insufficient evidence base to guide pharmacological treatment of anxiety in patients with underlying haematological conditions. The following case report is about a 50-year-old female with generalized anxiety disorder, social phobia, obsessive compulsive disorder, and alcohol abuse where pharmacological treatment of anxiety symptoms has been difficult as it would lead to bruising due to the patient’s underlying qualitative platelet dysfunction. Treatment with venlafaxine, citalopram, escitalopram, and clomipramine resulted in improvement and anxiety symptoms, as well as reduction in alcohol use, but pharmacological treatment has to be discontinued because of bruising and hematomas. In view of an active substance use disorder, benzodiazepines were avoided as a treatment option. The patient’s anxiety symptoms and comorbid alcohol abuse responded well to pharmacological treatment with buspirone which gradually titrated up to a dose of 30 mg BID. Patient was followed for around a six-month period while she was on buspirone before being discharged to family doctor’s care. Buspirone is unlikely to have a significant effect on platelet serotonin transponder and could be an effective alternative for pharmacological treatment of anxiety in patients with a bleeding diathesis.

  10. Treatment of anxiety disorders and comorbid alcohol abuse with buspirone in a patient with antidepressant-induced platelet dysfunction: a case report.

    Science.gov (United States)

    Mazhar, Mir; Hassan, Tariq; Munshi, Tariq

    2013-01-01

    The risk of abnormal bleeding with serotonin reuptake inhibitors has been known, but there is insufficient evidence base to guide pharmacological treatment of anxiety in patients with underlying haematological conditions. The following case report is about a 50-year-old female with generalized anxiety disorder, social phobia, obsessive compulsive disorder, and alcohol abuse where pharmacological treatment of anxiety symptoms has been difficult as it would lead to bruising due to the patient's underlying qualitative platelet dysfunction. Treatment with venlafaxine, citalopram, escitalopram, and clomipramine resulted in improvement and anxiety symptoms, as well as reduction in alcohol use, but pharmacological treatment has to be discontinued because of bruising and hematomas. In view of an active substance use disorder, benzodiazepines were avoided as a treatment option. The patient's anxiety symptoms and comorbid alcohol abuse responded well to pharmacological treatment with buspirone which gradually titrated up to a dose of 30 mg BID. Patient was followed for around a six-month period while she was on buspirone before being discharged to family doctor's care. Buspirone is unlikely to have a significant effect on platelet serotonin transponder and could be an effective alternative for pharmacological treatment of anxiety in patients with a bleeding diathesis. PMID:24416612

  11. In vitro function of random donor platelets stored for 7 days in composol platelet additive solution

    Directory of Open Access Journals (Sweden)

    Gupta Ashish

    2011-01-01

    Full Text Available Background and Aim: Platelets are routinely isolated from whole blood and stored in plasma for 5 days. This study was done to assess the in vitro function of random donor platelets stored for 7 days in composol platelet additive solution at 22°C. Materials and Methods: The study sample included 30 blood donors of both sex in State Blood Bank, C S M Medical University, Lucknow. Random donor platelets were prepared by the platelet-rich plasma method. Whole blood (350 ml was collected in anticoagulant Citrate Phosphate Dextrose Adenine triple blood bags. Random donor platelets were stored for 7 days at 22°C in platelet incubators and agitators with and without additive solution. Results: Platelet swirling was present in all the units at 22°C on day 7 with no evidence of bacterial contamination. Comparison of the mean values of platelet count, platelet factor 3, lactate dehydrogenase, pH, glucose and platelet aggregation showed no significant difference in additive solution while platelet factor 3, glucose and platelet aggregation showed significant difference (P < 0.001 on day 7 without additive solution at 22°C. Conclusion: Our study infers that the platelet viability and aggregation were the best maintained within normal levels on day 7 of storage in platelet additive solution at 22°C. Thus, we may conclude that in vitro storage of random donor platelets with an extended shelf life of 7 days using platelet additive solution may be advocated to improve the inventory of platelets.

  12. Evaluation of red blood cell and platelet antigen genotyping platforms (ID CORE XT/ID HPA XT) in routine clinical practice

    Science.gov (United States)

    Finning, Kirstin; Bhandari, Radhika; Sellers, Fiona; Revelli, Nicoletta; Villa, Maria Antonietta; Muñiz-Díaz, Eduardo; Nogués, Núria

    2016-01-01

    Background High-throughput genotyping platforms enable simultaneous analysis of multiple polymorphisms for blood group typing. BLOODchip® ID is a genotyping platform based on Luminex® xMAP technology for simultaneous determination of 37 red blood cell (RBC) antigens (ID CORE XT) and 18 human platelet antigens (HPA) (ID HPA XT) using the BIDS XT software. Materials and methods In this international multicentre study, the performance of ID CORE XT and ID HPA XT, using the centres’ current genotyping methods as the reference for comparison, and the usability and practicality of these systems, were evaluated under working laboratory conditions. DNA was extracted from whole blood in EDTA with Qiagen methodologies. Ninety-six previously phenotyped/genotyped samples were processed per assay: 87 testing samples plus five positive controls and four negative controls. Results Results were available for 519 samples: 258 with ID CORE XT and 261 with ID HPA XT. There were three “no calls” that were either caused by human error or resolved after repeating the test. Agreement between the tests and reference methods was 99.94% for ID CORE XT (9,540/9,546 antigens determined) and 100% for ID HPA XT (all 4,698 alleles determined). There were six discrepancies in antigen results in five RBC samples, four of which (in VS, N, S and Doa) could not be investigated due to lack of sufficient sample to perform additional tests and two of which (in S and C) were resolved in favour of ID CORE XT (100% accuracy). The total hands-on time was 28–41 minutes for a batch of 16 samples. Compared with the reference platforms, ID CORE XT and ID HPA XT were considered simpler to use and had shorter processing times. Discussion ID CORE XT and ID HPA XT genotyping platforms for RBC and platelet systems were accurate and user-friendly in working laboratory settings. PMID:26674823

  13. Effect of Platelet-Rich Plasma (PRP) versus Autologous Whole Blood on Pain and Function Improvement in Tennis Elbow: A Randomized Clinical Trial

    Science.gov (United States)

    Raeissadat, Seyed Ahmad; Sedighipour, Leyla; Rayegani, Seyed Mansoor; Bahrami, Mohammad Hasan; Bayat, Masume; Rahimi, Rosa

    2014-01-01

    Background. Autologous whole blood and platelet-rich plasma (PRP) have been both suggested to treat chronic tennis elbow. The aim of the present study was to compare the effects of PRP versus autologous whole blood local injection in chronic tennis elbow. Methods. Forty patients with tennis elbow were randomly divided into 2 groups. Group 1 was treated with a single injection of 2 mL of autologous PRP and group 2 with 2 mL of autologous blood. Tennis elbow strap, stretching, and strengthening exercises were administered for both groups during a 2-month followup. Pain and functional improvements were assessed using visual analog scale (VAS), modified Mayo Clinic performance index for the elbow, and pressure pain threshold (PPT) at 0, 4, and 8 weeks. Results. All pain and functional variables including VAS, PPT, and Mayo scores improved significantly in both groups 4 weeks after injection. No statistically significant difference was noted between groups regarding pain scores in 4-week follow-up examination (P > 0.05). At 8-week reevaluations, VAS and Mayo scores improved only in PRP group (P < 0.05). Conclusion. PRP and autologous whole blood injections are both effective to treat chronic lateral epicondylitis. PRP might be slightly superior in 8-week followup. However, further studies are suggested to get definite conclusion. PMID:24579044

  14. Core modular blood and brain biomarkers in social defeat mouse model for post traumatic stress disorder

    OpenAIRE

    Yang, Ruoting; Daigle Jr, Bernie J; Muhie, Seid Y; Hammamieh, Rasha; Jett, Marti; Petzold, Linda; Francis J Doyle

    2013-01-01

    Abstract Background Post-traumatic stress disorder (PTSD) is a severe anxiety disorder that affects a substantial portion of combat veterans and poses serious consequences to long-term health. Consequently, the identification of diagnostic and prognostic blood biomarkers for PTSD is of great interest. Previously, we assessed genome-wide gene expression of seven brain regions and whole blood in a social defeat mouse model subjected to various stress co...

  15. The interplay between platelets and coagulation

    OpenAIRE

    Weeterings, C.

    2009-01-01

    Platelet activation and blood coagulation are two processes often studied separately, but which cannot be seen independently from each other. Platelets play a pivotal role in coagulation, not only by providing negatively charged phospholipids, but also in localizing the coagulation process from a diffuse plasma environment to an anionic surface, most likely via specific receptors on the platelets. On the other hand, the main product of coagulation, thrombin, is a potent platelet activator, th...

  16. Mean platelet volume in gestational diabetes mellitus

    OpenAIRE

    Güdücü, Nilgün; Görmüş, Uzay; İşçi, Herman; Başgül Yiğiter, Alin; Dünder, İlkkan

    2015-01-01

    Objectives: This study aims to compare mean platelet volume of pregnants with gestational diabetes mellitus to a healthy control group and to detect the relationship between mean platelet volume and fasting blood glucose.Materials and methods: Patients with gestational diabetes mellitus (n=43) were compared to a healthy control group (n=43) retrospectively by searching medical records.Results: Platelet count and mean platelet volume of patients with gestational diabetes mellitus and the contr...

  17. Platelets: Covert Regulators of Lymphatic Development

    OpenAIRE

    Bertozzi, Cara C.; Hess, Paul R.; Kahn, Mark L.

    2010-01-01

    The field of platelet biology has rapidly expanded beyond the classical role of platelets in preventing blood loss and orchestrating clot formation. Despite the lack of transcriptional ability of these anuclear cell fragments, platelet function is now thought to encompass such diverse contexts as tissue repair, immune activation, primary tumor formation, and metastasis. Recent studies from multiple groups have turned the spotlight on an exciting new role for platelets in the formation of lymp...

  18. Effect of desipramine treatment on 3H-imipramine binding in the blood platelets of depressed patients

    International Nuclear Information System (INIS)

    Platelet imipramine binding (IB) was studied in depressed patients before and after treatment with desipramine for 17-28 days. Administration of desipramine was associated with a significant increase in Bmax. There was a trend for an increase in Kd, but it did not reach statistical significance. The net result of the changes in Bmax and Kd was an increase in IB. There were significant correlations between the change in depression ratings and pretreatment Kd, as well as the change in Kd during treatment. These results suggest that decreased IB is not a trait-dependent marker, but a state-dependent marker for depression. 46 references

  19. Study on the relationship between the serum thrombopoietin (TPO) levels and blood platelet counts in patients with various kinds of liver diseases

    International Nuclear Information System (INIS)

    Objective: To study the relationship between serum thrombopoietin (TPO) levels and thrombocytopenia in patients with various kinds of liver diseases. Methods: Serum TPO levels were determined with ELISA in 102 patients with various kinds of liver diseases (acute hepatitis n=9, chronic hepatitis n=80, hepatic cirrhosis n=13, etiology, HBV infection n=73, HBV + HEV n=13, HEV n=8, HCV n=6, autoimmune hepatitis n=2) and 30 controls. Results: The serum TPO levels in patients with various kinds of liver diseases were not significantly different from those in the controls (P>0.05). However, the blood platelet counts were significantly lower in all the patients (with the exception of the nine patients with acute hepatitis) than those in the controls (P 0.05). Conclusion: The lower TPO levels in patients with liver diseases could be only one of the many factors leading to thrombocytopenia. (authors)

  20. Seafood Consumption and Blood Mercury Concentrations in Jamaican Children With and Without Autism Spectrum Disorders

    OpenAIRE

    Rahbar, Mohammad H.; Samms-Vaughan, Maureen; Loveland, Katherine A.; Ardjomand-Hessabi, Manouchehr; Chen, Zhongxue; Bressler, Jan; Shakespeare-Pellington, Sydonnie; Grove, Megan L.; Bloom, Kari; Pearson, Deborah A.; Lalor, Gerald C.; Boerwinkle, Eric

    2012-01-01

    Mercury is a toxic metal shown to have harmful effects on human health. Several studies have reported high blood mercury concentrations as a risk factor for autism spectrum disorders (ASDs), while other studies have reported no such association. The goal of this study was to investigate the association between blood mercury concentrations in children and ASDs. Moreover, we investigated the role of seafood consumption in relation to blood mercury concentrations in Jamaican children. Based on d...

  1. Thiazine Red(+) platelet inclusions in Cerebral Blood Vessels are first signs in an Alzheimer's Disease mouse model.

    Science.gov (United States)

    Kniewallner, Kathrin M; Wenzel, Daniela; Humpel, Christian

    2016-01-01

    Strong evidence shows an association between cerebral vascular diseases and Alzheimer´s disease (AD). In order to study the interaction of beta-amyloid (Aβ) plaques with brain vessels, we crossbred an AD mouse model (overexpressing amyloid precursor protein with the Swedish-Dutch-Iowa mutations, APP_SweDI) with mice expressing green fluorescent protein (GFP) under the flt-1/VEGFR1 promoter in vessels (GFP_FLT1). Our data show, that only very few Aβ plaques were seen in 4-months old mice, focused in the mammillary body and in the lateral septal nucleus. The number of plaques markedly increased with age being most prominent in 12-months old mice. Thiazine Red was used to verify the plaques. Several Thiazine Red(+) inclusions were found in GFP(+) vessels, but only in non-perfused 4-months old mice. These inclusions were verified by Resorufin stainings possibly representing cerebral amyloid angiopathy. The inclusions were also seen in non-crossbred APP_SweDI but not in wildtype and GFP_FLT1 mice. In order to characterize these inclusions Flow Cytometry (FACS) analysis demonstrated that platelets were specifically stained by Thiazine Red(+), more pronounced when aggregated. In conclusion, our data show that Thiazine Red(+) inclusions representing aggregated platelets are a first pathological sign in AD before plaque development and may become important therapeutic targets in early AD. PMID:27345467

  2. Non-enzymatic modifications of prostaglandin H synthase 1 affect bifunctional enzyme activity - Implications for the sensitivity of blood platelets to acetylsalicylic acid.

    Science.gov (United States)

    Kassassir, Hassan; Siewiera, Karolina; Talar, Marcin; Stec-Martyna, Emilia; Pawlowska, Zofia; Watala, Cezary

    2016-06-25

    Due to its ability to inhibit the blood platelet PGHS-1, acetylsalicylic acid (ASA, Aspirin(®)) is widely used as a preventive agent in atherothrombotic diseases. However, its beneficial effects seem to be lower in diabetic patients, suggesting that protein glycation may impair effective ASA-mediated acetylation process. On the other hand, it is proposed that ASA can prevent some of the late complications of diabetes by lowering the extent of glycation at protein free amino groups. The aim of this work was to evaluate the extents of non-enzymatic N-glycosylation (glycation) and acetylation of blood platelet PGHS-1 (COX-1) and the competition between glycation and acetylation was investigated in order to demonstrate how these two reactions may compete against platelet PGHS-1. When PGHS-1 was incubated with glycating/acetylating agents (glucose, Glu; 1,6-bisphosphofructose, 1,6-BPF; methylglyoxal, MGO, acetylsalicylic acid, ASA), the enzyme was modified in 13.4 ± 1.6, 5.3 ± 0.5, 10.7 ± 1.2 and 6.4 ± 1.1 mol/mol protein, respectively, and its activity was significantly reduced. The prior glycation/carbonylation of PGHS-1 with Glu, 1,6-BPF or MGO decreased the extent of acetylation from 6.4 ± 1.1 down to 2.5 ± 0.2, 3.6 ± 0.3 and 5.2 ± 0.2 mol/mol protein, respectively, but the enzyme still remained susceptible to the subsequent inhibition of its activity with ASA. When PGHS-1 was first acetylated with ASA and then incubated with glycating/carbonylating agents, we observed the following reductions in the enzyme modifications: from 13.4 ± 1.6 to 8.7 ± 0.6 mol/mol protein for Glu, from 5.3 ± 0.5 to 3.9 ± 0.3 mol/mol protein for 1,6-BPF and from 10.7 ± 1.2 to 7.5 ± 0.5 mol/mol protein for MGO, however subsequent glycation/carbonylation did not significantly affect PGHS-1 function. Overall, our outcomes allow to better understand the structural aspects of the chemical competition between glycation and acetylation of PGHS-1

  3. Cord blood lymphocyte responses to food antigens for the prediction of allergic disorders.

    OpenAIRE

    Kondo, N.; Kobayashi, Y.; Shinoda, S; Kasahara, K.; Kameyama, T; Iwasa, S; Orii, T.

    1992-01-01

    Proliferative responses of cord blood lymphocytes (CBLs) to food antigens and cord blood IgE concentrations were measured in 37 full term newborn infants for the prediction of allergic disorders. In these 37 infants who were followed up for two years, allergic history of the family was found in four (sensitivity 57.1%) and cord blood IgE concentrations were greater than 0.5 IU/ml in three (sensitivity 42.9%) of seven infants who developed allergic disorders. When CBLs were stimulated twice by...

  4. The effect of time of day and exercise on platelet functions and platelet-neutrophil aggregates in healthy male subjects.

    Science.gov (United States)

    Aldemir, Hatice; Kiliç, Nedret

    2005-12-01

    Platelet activation state changes by exercise. The effect of exercise time on platelet activation state and formation of platelet-neutrophil aggregates are not known yet. In this study the effect of exercise and time of day were examined on platelet activity with platelet-neutrophil aggregates. Ten moderately active males aged 27+/- 1.63 (mean+/-S.D.) years completed sub-maximal (70% VO(2max)) exercise trials for 30 min. Blood pressure (BP) was recorded. Venous blood samples were obtained at rest, immediately post-exercise and after 30 min of recovery. Whole blood was analysed for haematocrit (Hct), haemoglobin (Hb), platelet count (PC), mean platelet count (MPV) and platelet aggregation (PA). Platelet-neutrophil aggregates and beta-thromboglobulin (beta-TG) levels were assayed. Platelet count showed significant increase after morning exercise ((236+/- 32)x10(9) l(-1) versus (202+/- 34)x10(9) l(-1) baseline, p 11912

  5. Blood coagulation and its alterations in hemorrhagic and thrombotic disorders.

    OpenAIRE

    Rapaport, S I

    1993-01-01

    Clinical observations have added to the understanding of basic mechanisms of blood coagulation and its alterations in certain hemorrhagic and thrombotic states. Much clinical evidence exists for concluding that the exposure of blood to tissue factor (thromboplastin) on tissue cells represents the key event initiating fibrin clot formation after tissue injury. This then results in the formation of activated factor VII (VIIa)-tissue factor complexes, which must activate both factor X and factor...

  6. Physiopathology of blood platelets: a model system for studies of cell-to-cell interaction. Progress report, November 1, 1979-October 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    This report covers the studies on basic mechanisms of cellular interactions, utilizing platelets as a model system and, when possible, concentrating on the influence that environmental factors (nutritional, metabolic, cellular, immunologic and others) have on them. The four major sections include: platelet interaction with tumor cells; a model for the study of cell-to-cell interaction; interaction of platelets with vessel walls; and platelet interactions with immune proteins.

  7. Blood Count Tests

    Science.gov (United States)

    Your blood contains red blood cells (RBC), white blood cells (WBC), and platelets. Blood count tests measure the number and types of cells in your blood. This helps doctors check on your overall health. ...

  8. Role of fluid shear stress in regulating VWF structure, function and related blood disorders.

    Science.gov (United States)

    Gogia, Shobhit; Neelamegham, Sriram

    2015-01-01

    Von Willebrand factor (VWF) is the largest glycoprotein in blood. It plays a crucial role in primary hemostasis via its binding interaction with platelet and endothelial cell surface receptors, other blood proteins and extra-cellular matrix components. This protein is found as a series of repeat units that are disulfide bonded to form multimeric structures. Once in blood, the protein multimer distribution is dynamically regulated by fluid shear stress which has two opposing effects: it promotes the aggregation or self-association of multiple VWF units, and it simultaneously reduces multimer size by facilitating the force-dependent cleavage of the protein by various proteases, most notably ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type repeats, motif 1 type 13). In addition to these effects, fluid shear also controls the solution and substrate-immobilized structure of VWF, the nature of contact between blood platelets and substrates, and the biomechanics of the GpIbα-VWF bond. These features together regulate different physiological and pathological processes including normal hemostasis, arterial and venous thrombosis, von Willebrand disease, thrombotic thrombocytopenic purpura and acquired von Willebrand syndrome. This article discusses current knowledge of VWF structure-function relationships with emphasis on the effects of hydrodynamic shear, including rapid methods to estimate the nature and magnitude of these forces in selected conditions. It shows that observations made by many investigators using solution and substrate-based shearing devices can be reconciled upon considering the physical size of VWF and the applied mechanical force in these different geometries. PMID:26600266

  9. Altered Regional Cerebral Blood Flow in Chronic Whiplash Associated Disorders

    NARCIS (Netherlands)

    Vállez García, David; Doorduin, Janine; Willemsen, Antoon T.M.; Dierckx, Rudi A.j.o.; Otte, Andreas

    2016-01-01

    There is increasing evidence of central hyperexcitability in chronic whiplash-associated disorders (cWAD). However, little is known about how an apparently simple cervical spine injury can induce changes in cerebral processes. The present study was designed (1) to validate previous results showing a

  10. Platelet aggregation following trauma

    DEFF Research Database (Denmark)

    Windeløv, Nis A; Sørensen, Anne M; Perner, Anders;

    2014-01-01

    We aimed to elucidate platelet function in trauma patients, as it is pivotal for hemostasis yet remains scarcely investigated in this population. We conducted a prospective observational study of platelet aggregation capacity in 213 adult trauma patients on admission to an emergency department (ED......). Inclusion criteria were trauma team activation and arterial cannula insertion on arrival. Blood samples were analyzed by multiple electrode aggregometry initiated by thrombin receptor agonist peptide 6 (TRAP) or collagen using a Multiplate device. Blood was sampled median 65 min after injury; median injury...... severity score (ISS) was 17; 14 (7%) patients received 10 or more units of red blood cells in the ED (massive transfusion); 24 (11%) patients died within 28 days of trauma: 17 due to cerebral injuries, four due to exsanguination, and three from other causes. No significant association was found between...

  11. B Cells and Platelets Harbor Prion Infectivity in the Blood of Deer Infected with Chronic Wasting Disease▿ †

    OpenAIRE

    Candace K Mathiason; Hayes-Klug, Jeanette; Hays, Sheila A.; Powers, Jenny; Osborn, David A.; Dahmes, Sallie J.; Miller, Karl V.; Warren, Robert J., II; Mason, Gary L.; Telling, Glenn C.; Young, Alan J; Hoover, Edward A.

    2010-01-01

    Substantial evidence for prion transmission via blood transfusion exists for many transmissible spongiform encephalopathy (TSE) diseases. Determining which cell phenotype(s) is responsible for trafficking infectivity has important implications for our understanding of the dissemination of prions, as well as their detection and elimination from blood products. We used bioassay studies of native white-tailed deer and transgenic cervidized mice to determine (i) if chronic wasting disease (CWD) b...

  12. Autologous Platelet Gel: An In Vitro Analysis of Platelet-Rich Plasma Using Multiple Cycles

    OpenAIRE

    Christensen, Kevin; Vang, See; Brady, Chad; Isler, Jack; Allen, Keith; Anderson, John; Holt, David

    2006-01-01

    Autologous platelet gel (APG) has become an expanding field for perfusionists. By mixing platelet-rich plasma (PRP) with thrombin and calcium, platelet gel is prepared and used in many surgical settings. There are many devices used to produce PRP. This study evaluates the Medtronic Magellan Autologous Platelet Separator. The purpose of this study was to show that processing two cycles of the same syringe could reduce the amount of blood required to produce a specific volume of PRP. Three 60-m...

  13. Role of platelets in inflammation

    Directory of Open Access Journals (Sweden)

    Kadir Serkan Yalçın

    2012-09-01

    Full Text Available Inflammation, which is extremely useful process for humanbody is the response of living vascular tissues topathological phenomena that removes the pathogens andinitiates the healing procedure. Microorganisms, physicaltrauma, chemical, mechanical, irradiation, or thermal injury,ischemia and immune reactions are most commoncauses of this exceptionally important event for humanbody. Platelets are non-nucleated cells in blood that producedin bone marrow as derived from megakaryocytes.Apart from stop bleeding and achieving hemostasis thereare incredibly important roles of platelets in inflammation.Platelets contain important mediators for inflammationlike neutrophils or macrophages and can alter the courseof mechanism. In this article changing platelet function ininflammation and the effect of these functions to the processof inflammation will be discussed.Key words: Platelet, inflammation, cytokines

  14. Subclinical Posttraumatic Stress Disorder Symptoms: Relationships with Blood Pressure, Hostility, and Sleep

    Science.gov (United States)

    Zinzow, Heidi M.; Hibdon, Melissa A.; Nathan, Aaron W.; Morrison, Anastasia V.; Hayden, Gregg W.; Lindberg, Caitlyn; Switzer, Fred S.

    2016-01-01

    The purpose of this study was to examine the relationships among subclinical PTSD symptoms, blood pressure, and several variables linked to both frank PTSD and the basic psychobiological adaptation to stress. The authors recruited a sample of 91 healthy, young men and women between 18 and 35 years. We examined links among subclinical posttraumatic stress disorder symptoms, blood pressure, sleep quality, and hostility. Posttraumatic stress disorder symptoms were associated with poorer sleep quality and higher hostility scores in both women and men. In men, PTSD symptoms were also associated with elevated resting diastolic blood pressure, and sex was an important moderator of that relationship. Moreover, sleep quality and hostility are substantive mediators of the relationship between diastolic blood pressure and PTSD. Behavioral interventions designed to increase sleep quality and restructure hostile attitudes could potentially serve as preventive interventions for PTSD and the underlying cardiovascular comorbidities in young adults. PMID:27403340

  15. Platelets: covert regulators of lymphatic development.

    Science.gov (United States)

    Bertozzi, Cara C; Hess, Paul R; Kahn, Mark L

    2010-12-01

    The field of platelet biology has rapidly expanded beyond the classical role of platelets in preventing blood loss and orchestrating clot formation. Despite the lack of transcriptional ability of these anuclear cell fragments, platelet function is now thought to encompass such diverse contexts as tissue repair, immune activation, primary tumor formation, and metastasis. Recent studies from multiple groups have turned the spotlight on an exciting new role for platelets in the formation of lymphatic vessels during embryonic development. Genetic experiments demonstrate that podoplanin, a transmembrane protein expressed on lymphatic endothelial cells, engages the platelet C-type lectin-like receptor 2 (CLEC-2) when exposed to blood, leading to SYK-SLP-76-dependent platelet activation. When components of this pathway are disrupted, aberrant vascular connections form, resulting in blood-lymphatic mixing. Furthermore, platelet-null embryos manifest identical blood-lymphatic mixing. The identification of platelets as the critical cell type mediating blood-lymphatic vascular separation raises new questions in our understanding of lymphatic development and platelet biology. PMID:21071706

  16. The relationship between the level of activation markers of platelets in peripheral blood around operation and lung cancer%肺癌患者外周血血小板活化标志物水平及其临床意义

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective: To investigate the relationship between the activation markers of platelets and the lung cancer.Methods: Based on international stages of lung cancer in 1997, lung cancer patients of 120 cases diagnosed by pathology as well as with operation indication were selected as the experimental group.During the process of experiment, 60 cases concluded as healthy in the physical examination were chosen as control group.The activation markers of platelets were detected by FCM method.The experimental result would be processed by SPSS 11.5.Results: The level of activation markers of platelets in peripheral blood of lung cancer patients was significantly higher than those healthy people(P<0.01).The level of activation markers of platelets in peripheral blood of lung cancer patients on the seventh postoperative day was significantly lower than that before operation and on the first postoperative day(P<0.01).The level of activation markers of platelets in peripheral blood of lung cancer patients was closely related to the size of the primary tumor, lymph node status and stages, but not to the grade of cell differentiation, type of tumor, age, sex of the patients(P>0.05).Conclusion: Elevation of the level of activation markers of platelets in peripheral blood exists in lung cancer patients and the levels of activation marker of platelets plays an important role in tumor growth and lymphatic metastasis.The levels of activation markers of platelets maybe a predictor for prognosis.

  17. Is Platelet-rich plasma superior to whole blood in the management of chronic tennis elbow: one year randomized clinical trial

    Science.gov (United States)

    2014-01-01

    Background Lateral humeral epicondylitis, or ‘tennis elbow’, is a common condition with a variety of treatment options. Platelet-rich plasma (PRP) and Autologous Whole Blood (AWB) represent new therapeutic options for chronic tendinopathies including tennis elbow. The aim of the present study was to compare the long term effects of PRP versus autologous whole blood local injection in patients with chronic tennis elbow. Methods Seventy six patients with chronic lateral humeral epicondylitis with duration of symptoms more than 3 months were included in this study and randomized into 2 groups. Group 1 was treated with a single injection of 2 mL of autologous leukocyte rich PRP (4.8 times of plasma) and group 2 with 2 mL of AWB. Tennis elbow strap, stretching and strengthening exercises were administered for both groups. Pain and functional improvements were assessed using visual analogue scale (VAS), Mayo score (modified Mayo Clinic performance index for the elbow) and pressure pain threshold (PPT) at 0, 4, 8 weeks and 6 and 12 months. Results All pain variables including VAS, PPT and Mayo scores improved significantly in both groups at each follow up intervals compared to baseline. No statistically significant difference was noted between groups regarding pain, functional scores and treatment success rates in all follow up examinations (P >0/05). Conclusion PRP and autologous whole blood injections are both effective methods to treat chronic lateral epicondylitis and their efficacy persisted during long term follow up. PRP was not superior to AWB in long term follow up. PMID:24635909

  18. 围产期妇女外周血大血小板与纤维蛋白原相关性分析%Analysis of the relationship between peripheral blood platelet and fibrinogen of perinatal women

    Institute of Scientific and Technical Information of China (English)

    张燕; 李飞

    2014-01-01

    Objective To investigate the relationship between peripheral blood platelet and fibrinogen of peri-natal women.Methods 309 cases of perinatal women were collected,peripheral blood platelet and fibrinogen tested by manual method and VASTECCA7000 coagulation analyzer.Results The large platelets positive rate was 53.39%in 309 cases ,122 cases of normal women′s big platelet positive rate was 13.11%.It′s a significant difference be-tween two group(P<0.05).90 cases of patients with large platelet and fibrinogen increased.75 cases of patients with large platelet and fibrinogen was not increased .52 cases of patients with negative large platelet and fibrinogen in-creased.92 cases of patients with negative large platelet and fibrinogen was not increased .There were significantly different between large platelet and fibrinogen (P<0.05).Conclusion the perinatal maternal peripheral blood plate-let than normal women,perinatalmaternal peripheral blood platelet increased along with the increased fiberprotein.%目的:对围产期妇女外周血大血小板和纤维蛋白原的分析探讨。方法运用手工法和 VASTEC CA7000凝血分析仪分别对309例围产期妇女外周血进行直接涂片镜检和纤维蛋白原的检测。结果309例围产期妇女大血小板阳性率为53.39%,122例正常妇女大血小板阳性率为13.11%。围产组与正常组差异有统计学意义(P <0.05);大血小板阳性,纤维蛋白原增高的为90例,大血小板阳性,纤维蛋白原不增高的为75例,大血小板阴性,纤维蛋白原增高的为52例,大血小板阴性,纤维蛋白原不增高的为92例。大血小板与纤维蛋白原的相关分析差异有统计学意义(P <0.05)。结论围产期孕妇外周血中大血小板较正常妇女多,围产期孕妇外周血大血小板增多伴随着纤维蛋白增高。

  19. Platelet aggregation in platelet suspensions from Mongolian gerbils (Meriones unguiculatus).

    OpenAIRE

    Agwu, D E; Holub, B J; Johnstone, I. B.; Crane, S.

    1983-01-01

    Blood obtained from Mongolian gerbils (Meriones unguiculatus) by cardiac puncture was used to develop a method for preparing platelet suspensions suitable for biochemical and aggregometric studies. The aggregation responses of gerbil platelet suspensions to 10 microM adenosine diphosphate and to 0.2 U/mL thrombin were immediate and irreversible. In addition, thrombin produced a short lag period. Bovine acid-soluble collagen (1:800) produced a long lag period coupled with an irreversible aggre...

  20. Determination of vascular endothelial growth factor (VEGF) in circulating blood: significance of VEGF in various leucocytes and platelets

    DEFF Research Database (Denmark)

    Werther, K; Christensen, Ib Jarle; Nielsen, Hans Jørgen

    2002-01-01

    AIM: The sources of increased vascular endothelial growth factor (VEGF) concentrations in peripheral blood from cancer patients are not known in detail. The aim of the present study was to evaluate correlations between the VEGF content in isolated leucocyte subpopulations and VEGF concentrations ...

  1. Alterations of Regional Cerebral Blood Flow in Major Depressive Disorder

    International Nuclear Information System (INIS)

    The authors analyzed how the regional cerebral blood flow (rCBF) findings of patients with major depression differ from the normal control, and our results were compared to previous reports. Twelve patients fulfilling DSM-IV criteria for major depression who were off all psychotropic medications for > 4 weeks (male: 7, female: 5, age range: 19∼52 years, average age: 29.3±9.9 years) and 14 normal volunteers (male: 8, female: 6, age range: 19∼53 years, average age: 31.4±9.2 years) were recruited. Images of brain perfusion SPECT were obtained using Tc-99m ECD and patterns of the rCBF were compared between patients with major depression and the healthy control subjects. The patients with major depression showed increase of the r-CBF in right lingual gyrus, right fusiform gyrus, left lingual gyrus, left precuneus, and left superior temporal gyrus, and showed decrease of r-CBF in right pons, left medial frontal gyrus, cingulate gyrus of left limbic lobe, cingulate gyrus of right frontal lobe, and cingulate gyrus of right limbic lobe compared to the normal control. The Tc-99m ECD brain perfusion SPECT findings in our study did not differ from the previously reported regional cerebral blood flow pattern of patients with major depression. Especially, decreased rCBF pattern typical to major depression patients in the right pons, left medial frontal gyrus, and cingulate regions was clearly demonstrated

  2. The effect of centrifugation speed and time on pre-analytical platelet activation

    DEFF Research Database (Denmark)

    Söderström, Anna C; Nybo, Mads; Nielsen, Christian; Vinholt, Pernille J

    2016-01-01

    . METHODS: Citrate- and EDTA-anticoagulated blood from healthy volunteers were centrifuged at 80-10,000 g for 5-15 min to prepare plasma and platelet-rich plasma. Pre-analytical platelet activation was assessed by flow cytometric measurement of platelet P-selectin (CD62p) expression. Blood cell counts, mean...... platelet volume (MPV), immature platelet fraction (IPF), and platelet distribution width (PDW) were measured. Platelet aggregation in platelet-rich plasma induced by arachidonic acid (AA), ADP or thrombin receptor activator peptide-6 (TRAP) was tested by 96-well aggregometry. RESULTS: The median percentage......%-15%), p<0.001. Platelet count in plasma samples decreased with increasing speed but platelets were only completely removed if plasma was re-centrifuged. In platelet-rich plasma, increasing centrifugation speed significantly increased platelet yield but decreased contamination from other blood cells...

  3. Types of Blood Donations

    Science.gov (United States)

    ... Double Red Cell Plasma Platelets Red Cells What blood donation type is best for me? **If you do not ... blood type, a whole blood donation is recommended** Blood Donation Types: Volunteer Donations The standard or most common type ...

  4. Brief Report: Whole Blood Serotonin Levels and Gastrointestinal Symptoms in Autism Spectrum Disorder

    Science.gov (United States)

    Marler, Sarah; Ferguson, Bradley J.; Lee, Evon Batey; Peters, Brittany; Williams, Kent C.; McDonnell, Erin; Macklin, Eric A.; Levitt, Pat; Gillespie, Catherine Hagan; Anderson, George M.; Margolis, Kara Gross; Beversdorf, David Q.; Veenstra-VanderWeele, Jeremy

    2016-01-01

    Elevated whole blood serotonin levels are observed in more than 25% of children with autism spectrum disorder (ASD). Co-occurring gastrointestinal (GI) symptoms are also common in ASD but have not previously been examined in relationship with hyperserotonemia, despite the synthesis of serotonin in the gut. In 82 children and adolescents with ASD,…

  5. Attention-deficit/hyperactivity disorder and disruptive behavior disorders in adolescence related to levels of platelet MAO-B and polymorphisms in two candidate genes

    OpenAIRE

    Malmberg, Kerstin

    2011-01-01

    Background: Attention-Deficit/Hyperactivity Disorder (ADHD) and Disruptive Behavior Disorders (DBD) (including Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD)), are common developmental and behaviour diagnoses among adolescents. Several of their symptoms, have been linked to genotypes (e.g. monoamine oxidase A Variable Number of Tandem Repeats (MAO-A VNTR) and the 5–HydroxyTryptamine Transporter gene-Linked Polymorphic Region (5-HTT LPR)) as well as to platel...

  6. Cerebral blood flow and metabolism analysis in parkinsonian disorders

    International Nuclear Information System (INIS)

    Main metabolic and hemodynamic abnormalities detected by single photon emission computerized tomography and positron emission tomography in extra-pyramidal disorders are reported. In the first stage of Parkinson's disease, cortical metabolism and perfusion can be in normal range or moderately and uniformly reduced. A significant decrease may appear with the disease evolution. Marked abnormalities are observed in parkinsonian patients with dementia (subcortical dementia), involving especially the frontal cortex. A marked diffuse cortical hypo-metabolism (temporal, parietal, occipital and frontal cortex) may suggest the diagnosis of dementia with Lewy bodies, especially in case of fluctuating cognitive decline with recurrent visual hallucinations. In progressive supra-nuclear palsy, a frontal cortex hypo-metabolism is reported precociously, preceding sometimes the cognitive impairment. Metabolic pattern find in multiple system atrophy reflects dysfunction of both nigrostriatal pathways and striatum, with a decrease glucose uptake in putamen and caudate nucleus which also involves cerebellum for the patients with cerebellar syndrome. In cortico-basal degeneration, asymmetric fronto-parietal and striatal hypo-metabolism observed in the controlateral hemisphere to the clinically most affected side, constitute the main characteristic well correlated with apraxia. (author)

  7. Diagnosis and epidemiology of red blood cell enzyme disorders

    Directory of Open Access Journals (Sweden)

    Richard Van Wijk

    2013-03-01

    Full Text Available The red blood cell possess an active metabolic machinery that provides the cell with energy to pump ions against electrochemical gradients, to maintain its shape, to keep hemoglobin iron in the reduced (ferrous form, and to maintain enzyme and hemoglobin sulfhydryl groups. The main source of metabolic energy comes from glucose. Glucose is metabolized through the glycolytic pathway and through the hexose monophosphate shunt. Glycolysis catabolizes glucose to pyruvate and lactate, which represent the end products of glucose metabolism in the erythrocyte. Adenosine diphosphate (ADP is phosphorylated to adenosine triphosphate (ATP, and nicotinamide adenine dinucleotide (NAD+ is reduced to NADH in glycolysis. 2,3- Bisphosphoglycerate, an important regulator of the oxygen affinity of hemoglobin, is generated during glycolysis by the Rapoport-Luebering shunt. The hexose monophosphate shunt oxidizes glucose-6-phosphate, reducing NADP+ to reduced nicotinamide adenine dinucleotide phosphate (NADPH. The red cell lacks the capacity for de novo purine synthesis but has a salvage pathway that permits synthesis of purine nucleotides from purine bases...

  8. Hormonal contraception and platelet function.

    Science.gov (United States)

    Saleh, A A; Ginsburg, K A; Duchon, T A; Dorey, L G; Hirata, J; Alshameeri, R S; Dombrowski, M P; Mammen, E F

    1995-05-15

    73 healthy women (29 controls, 25 using OCs, and 19 using Norplant) were selected from the clinic population at North Oakland Medical Center for inclusion in this study after obtaining informed consent. Age, race, height, weight, blood pressure, and cigarette smoking were recorded for each subject. 12 patients were on monophasic OCs while 13 were on triphasic preparations. Both hormonal contraceptive groups had used their particular contraceptive for at least 3 months prior to blood drawing. Platelet tests were performed within 2 hours of sample collection: platelet counts (PLC) and mean platelet volume (MPV) were determined on an Automated Platelet Counter (Baker 810 Platelet Analyzer). Whole blood aggregation was performed on a platelet aggregometer (Chrono-Log, Model 550) using both ADP (ADP, 5 mM) and collagen (COLL, 2 mcg/ml) as inducing agents. Demographic differences were not significant (p 0.05) among the 3 treatment groups, whose average age was 25.3-25.8 years old. Furthermore, no significant differences (p 0.05) in platelet function were detected among controls or subjects receiving either oral contraceptives or Norplant, compared to control patients. The mean platelet counts (X 10/9/L) were 223 for OC users, 231 for Norplant users, and 232 for controls. The respective platelet aggregation (ADP, ohms) values were 12.5, 18.0, and 19.2 as well as (COLL, ohms) 35.6, 40.7, and 39.0. These results demonstrated that there is no evidence for altered platelet function, with the testing methods employed, in women using either Norplant or combination low dose oral contraceptives. To date, several studies have examined this issue, with contradictory reports about the effects of hormonal contraceptives in platelet function. After controlling for differences between various steroid preparations and other such confounding variables, some of these conflicting conclusions could be the result of a lack of uniformity among the methods used to evaluate platelet aggregation

  9. Platelet inhibition by nitrite is dependent on erythrocytes and deoxygenation.

    Directory of Open Access Journals (Sweden)

    Sirada Srihirun

    Full Text Available BACKGROUND: Nitrite is a nitric oxide (NO metabolite in tissues and blood, which can be converted to NO under hypoxia to facilitate tissue perfusion. Although nitrite is known to cause vasodilation following its reduction to NO, the effect of nitrite on platelet activity remains unclear. In this study, the effect of nitrite and nitrite+erythrocytes, with and without deoxygenation, on platelet activity was investigated. METHODOLOGY/FINDING: Platelet aggregation was studied in platelet-rich plasma (PRP and PRP+erythrocytes by turbidimetric and impedance aggregometry, respectively. In PRP, DEANONOate inhibited platelet aggregation induced by ADP while nitrite had no effect on platelets. In PRP+erythrocytes, the inhibitory effect of DEANONOate on platelets decreased whereas nitrite at physiologic concentration (0.1 µM inhibited platelet aggregation and ATP release. The effect of nitrite+erythrocytes on platelets was abrogated by C-PTIO (a membrane-impermeable NO scavenger, suggesting an NO-mediated action. Furthermore, deoxygenation enhanced the effect of nitrite as observed from a decrease of P-selectin expression and increase of the cGMP levels in platelets. The ADP-induced platelet aggregation in whole blood showed inverse correlations with the nitrite levels in whole blood and erythrocytes. CONCLUSION: Nitrite alone at physiological levels has no effect on platelets in plasma. Nitrite in the presence of erythrocytes inhibits platelets through its reduction to NO, which is promoted by deoxygenation. Nitrite may have role in modulating platelet activity in the circulation, especially during hypoxia.

  10. EDTA抗凝末梢血放置时间对血小板测定影响的分析%Influence of storage time on the determination of EDTA anticoagulated peripheral blood platelet

    Institute of Scientific and Technical Information of China (English)

    王纪华; 王峰

    2011-01-01

    Objective:To explore the influence of differen placing time of peripheral blood platelet at room temperature in measuring results. Methods: 186 cases of clinic patients peripheral blood by ethylenediamine tetraacetate two potassium anticoagulation, determination respectively on instantly, 5 min, 10 min, 20 min, 30 min, 60 min with Sysmex xs -800i blood analyzer -platelet in room temperature ( 18℃ to 25℃ ), and simultaneously manual counting spectrometry , the results are compared. Results: The results comparative differences are statistically significant with Sysmex xs -800i blood platelet in peripheral blood analyzer between in 10 ~ 60 min determination and in instantly, 5 min( P < 0.05 ). Conclusion: Determination of PLT with the peripheral blood in 10~60 min results are more stable.%目的:探讨末梢血样本在室温下放置时间对血小板测定的影响.方法:186例门诊患者末梢血经乙二胺四乙酸二钾抗凝,置室温(18℃~25℃)分别于即刻、5 min、10 min、20 min、30 min、60 min采用Sysmex xs-800i血细胞分析仪进行血小板测定同时进行手工计数法测定并对结果进行比较分析.结果:Sysmex xs-800i血细胞分析仪的末梢血血小板在10 min~60 min测定与即刻、5 min结果比较差异有统计学意义(P<0.05).结论:末梢血常规测定中PLT在10min~60 min结果比较稳定.

  11. Thrombokinetics with In-111-oxine labelled platelets

    International Nuclear Information System (INIS)

    Indium-111-oxine has been employed as a redioactive platelet label for thrombosis imaging and thrombokinetic studies in man. To evaluate it's suitability for platelet survival and turnover, thrombokinetic studies were carried out in hematological normal subjects, in patients with idiopathic thrombocytopenic purpura (ITP) and chronic congestive splenomegaly. For In-111-oxine labelled platelets, platelets were collected by differential centrifugation from 44 ml of whole blood drawn into 6 ml of acid citrate dextrose solution. Platelet suspension was incubated with In-111-oxine, which was extracted before use by the method of Thakur and co-workers. The survival, recovery and turnover of In-111-labeled platelets were 8.6 +- 0.5 days, 63.0 +- 5.4% and 3.9 +- 0.3 x 104/ μl/day, respectively, which were similar with those of Cr-51 method. Platelet disappearance curves labelled with In-111 and Cr-51 simultaneously were similar in one case. In patients with ITP, platelet survival shortened in the same degree with Cr-51 method. The two simultaneous labeling studies between In-111 and Cr-51 showed no differences. In the patients with congestive splenomegaly, the same results were obtained. Thrombokinetic studies with In-111-oxine labelled platelets offer the advantages of reduced blood requirements, and the ability to perform external imaging of platelet distribution. (author)

  12. Platelet-rich fibrin: Evolution of a second-generation platelet concentrate

    Directory of Open Access Journals (Sweden)

    Sunitha Raja V

    2008-01-01

    Full Text Available Platelet-rich plasma (PRP is a platelet concentrate that has been used widely to accelerate soft-tissue and hard-tissue healing. The preparation of PRP has been described by several authors. Platelet-rich fibrin (PRF was first described by Choukroun et al. in France. It has been referred to as a second-generation platelet concentrate, which has been shown to have several advantages over traditionally prepared PRP. Its chief advantages include ease of preparation and lack of biochemical handling of blood, which makes this preparation strictly autologous. This article describes the evolution of this novel platelet concentrate, referred to as PRF.

  13. Blood platelets contain and secrete laminin-8 (alpha4beta1gamma1) and adhere to laminin-8 via alpha6beta1 integrin.

    Science.gov (United States)

    Geberhiwot, T; Ingerpuu, S; Pedraza, C; Neira, M; Lehto, U; Virtanen, I; Kortesmaa, J; Tryggvason, K; Engvall, E; Patarroyo, M

    1999-12-15

    Laminins, a family of heterotrimeric proteins with cell adhesive/signaling properties, are characteristic components of basement membranes of vasculature and tissues. In the present study, permeabilized platelets were found to react with a monoclonal antibody to laminin gamma1 chain by immunofluorescence. In Western blot analysis of platelet lysates, several monoclonal antibodies to gamma1 and beta1 laminin chains recognized 220- to 230-kDa polypeptides, under reducing conditions, and a structure with much slower electrophoretic mobility under nonreducing conditions. Immunoaffinity purification on a laminin beta1 antibody-Sepharose column yielded polypeptides of 230, 220, 200, and 180 kDa from platelet lysates. In the purified material, mAbs to beta1 and gamma1 reacted with the two larger polypeptides, while affinity-purified rabbit antibodies to laminin alpha4 chain recognized the smallest polypeptide. Identity of the polypeptides was confirmed by microsequencing. One million platelets contained on average 1 ng of laminin (approximately 700 molecules per cell), of which 20-35% was secreted within minutes after stimulation with either thrombin or phorbol ester. Platelets adhered to plastic surfaces coated with the purified platelet laminin, and this process was largely inhibited by antibodies to beta1 and alpha6 integrin chains. We conclude that platelets contain and, following activation, secrete laminin-8 (alpha4beta1gamma1) and that the cells adhere to the protein by using alpha6beta1 integrin. PMID:10585296

  14. Bone Augmentation in Rabbit Tibia Using Microfixed Cobalt-Chromium Membranes with Whole Blood and Platelet-Rich Plasma

    Directory of Open Access Journals (Sweden)

    Oscar A. Decco

    2015-07-01

    Full Text Available Background: Bone augmentation is a subject of intensive investigation in regenerative bone medicine and constitutes a clinical situation in which autogenous bone grafts or synthetic materials are used to aid new bone formation. Method: Based on a non-critical defect, Co-Cr barrier membranes were placed on six adult Fauve de Bourgogne rabbits, divided into two groups: whole blood and PRP. Three densitometric controls were performed during the experiment. The animals were euthanized at 30, 45, 60, and 110 days. The presence of newly formed bone was observed. Samples for histological studies were taken from the augmentation center. Results: External and internal bone tissue augmentation was observed in almost all cases. Significant differences between PRP- and whole blood–stimulated bone augmentation were not observed. At 60 days, bones with PRP presented higher angiogenesis, which may indicate more proliferation and cellular activity. Conclusion: PRP activates the bone regeneration process under optimized conditions by stimulation of osteoblast proliferation after six weeks, when a significant difference in cellular activity was observed. Membranes could stimulate bone augmentation at the site of placement and in the surrounding areas.

  15. Impact of JAK2 V617F mutation on hemogram variation in patients with non-reactive elevated platelet counts.

    Directory of Open Access Journals (Sweden)

    Juan Zhou

    Full Text Available BACKGROUND: Non-reactive platelet counts elevation occurs mainly in myeloproliferative disorders (MPDs, which have been reported to be closely associated with JAK2 V617F mutation. Complete blood cell count (CBC is essential in diagnosis of MPDs, however, the impact of JAK2 V617F mutation on the patients' hemogram variation remains not clear. METHODS: JAK2 V617F mutation was detected by allele specific real-time quantitative fluorescence PCR (AS-qPCR. RESULTS: Of the 402 non-reactive platelet elevating patients, JAK2 V617F mutation was detected in 222 (55.2% patients. RBC counts, WBC counts, platelet-large contrast ratio (P-LCR, platelet distribution width (PDW and mean platelet volume (MPV were much higher in JAK2 V617F mutated patients, except platelet counts. In addition, when the patients were classified into subgroups by blood cell counts, it was found that JAK2 V617F mutation rate increased progressively with the increase of RBC counts and WBC counts, other than platelet counts. Furthermore, trilineage hyperplasia group showed highest JAK2 V617F mutation rate (93.26%, followed by the bilineage hyperplasia groups. Lastly, JAK2 V617F mutant allele burden was found much higher in polycythemia vera (PV patients [median(P25-P75: 45.02%(35.12%-54.22%] than in essential thrombocythemia (ET patients [median(P25-P75: 28.23%(17.77%-41.66%], and that it increased with WBC counts (r = 0.393, p = 0.000 and RBC counts(r = 0.215, p = 0.001, other than platelet counts (r = -0.051, p = 0.452. Further analysis revealed that in ET patients, JAK2 V617F mutant allele burden correlated with WBC counts and platelet counts positively, other than RBC counts, while in PV patients, it correlated with WBC counts and RBC counts positively, but not platelet counts. CONCLUSIONS: JAK2 V617F mutation occurs frequently in patients with non-reactive elevated platelet counts. The presence of JAK2 V617F mutation has great impact on hemogram variation

  16. RELATIONS BETWEEN SELECTED INDICATORS OF BLOOD AND MILK OF DAIRY COWS WITH METABOLIC DISORDERS

    Directory of Open Access Journals (Sweden)

    Jaroslav Kováčik

    2013-02-01

    Full Text Available The aim of this work was to monitor the relations between selected indicators of technological properties of milk and blood biochemical parameters of dairy cows with metabolic disorders. Thirty-two cows were chosen, which were divided into 3 groups: first group - cows with metabolic problems of acidosis, second group - cows with metabolic problems of alkalosis, third group - healthy cows. Blood, urine and milk samples were collected. Urea, total lipids, total proteins, glucose and calcium was determined in the blood serum. Pure acidobasic forms, pH and density of urine were determined. Proteins, lactose, non-fat-solids, somatic cells count, calcium, urea, titratable acidity, fermentability, rennetability and thermostability were determined in samples of milk. Significant negative dependences were observed in the group of cows with metabolic problems of acidosis between urea in blood and in milk (r = -0.694, P <0.05, between calcium in blood and in milk (r = -0.653, P <0, 05, and between calcium in milk and glucose in blood (r = -0.648, P <0.05. In the group of cows with alkalosis, statistically significant correlation between total lipids in blood and fat in milk was found (r = -0.879, P <0.05.

  17. Performance evaluation of PL-11 platelet analyzer

    Institute of Scientific and Technical Information of China (English)

    张有涛

    2013-01-01

    Objective To evaluate and report the performance of PL-11 platelet analyzer. Methods Intravenous blood sam-ples anticoagulated with EDTA-K2 and sodium citrate were tested by the PL-11 platelet analyzer to evaluate the intra-assay and interassay coefficient of variation(CV),

  18. Effects of dermatan sulfate derivatives on platelet surface P-selectin expression and protein C activity in blood of inflammatory bowel disease patients

    Institute of Scientific and Technical Information of China (English)

    Sheng-Li Ji; Hai-Yan Du; Yan-Qing Chi; Hui-Fei Cui; Ji-Chao Cao; Mei-Yu Geng; Hua-Shi Guan

    2004-01-01

    AIM: To investigate the effect of dermatan sulfate (DS)derivatives on platelet surface P-selectin expression and blood activated protein C (APC) activity in patients with inflammatory bowel disease (IBD), and to clarity the antiinflammatory mechanism of DS derivatives.METHODS: Dermatan sulfate (DS) was sulfated with chlorosulfonic acid to prepare polysulfated dermatan sulfate (PSDS). The major disaccharides of DS and PSDS were determined by 1H nuclear magnetic resonance spectroscopy (1H-NMR) and 13C-NMR. Both DS and PSDS were depolymerized with hydrogen peroxide. The fragments were separated by gel filtration chromatography. The effects of DS derivatives on P-selectin expression were assayed by ELISA method,and blood APC activity was assayed by the synthetic chromogenic substrate method.RESULTS: The major disaccharides of DS and PSDS were IdoA-1→3-GalNAc-4-SO3 and IdoA-2SO3-1→3-GalNAc4, 6-diSO3, respectively. Compared with the adenosine diphosphate stimulated group and IBD control group, DS and its derivatives all had significant inhibitory effects on P-selectin expression (P<0.01), but there was no difference between DS-derived oligosaccharides (DSOSs) and PSDS-derived oligosaccharides (PSDSOSs). The experiments on APC activity showed that DS and its derivatives all enhanced APC activity. The most active DSOS was the one with a relative molecular weight (Mr) of 4 825, which enhanced the APC activity from 106.5±11.5% to 181.8±22.3% (P<0.01). With the decrease of Mr, the activity of DSOSs decreased gradually. The effect of PSDS on APC activity enhancement was more significant than that of DS, and the APC activity was raised to 205.2±22.1% (P<0.01). All the PSDSOSs were more active than DSOSs on the basis of comparable Mr. With the decrease of Mr, the activity of PSDSOSs increased gradually, and the most active PSDSOS was PSDSOS3 with Mr of 2 749, which enhanced the APC activity to 331.2±27.8% (P<0.01), then the activity of PSDSOSs decreased gradually

  19. Effects of hydrocortisone and aminophylline on the aggregation of equine platelets in vitro

    OpenAIRE

    Casella, Stefania; Giudice, Elisabetta; Giannetto, Claudia; Marafioti, Simona; Piccione, Giuseppe

    2011-01-01

    The purpose of this study was to evaluate in vitro the effects of hydrocortisone and aminophylline on adenosine diphosphate (ADP)-induced platelet aggregation in horses. Blood samples from 30 healthy Thoroughbred horses were collected by via jugular venipuncture to assess platelet aggregation. Platelet-rich and platelet-poor plasma were prepared from all samples by centrifugation and divided into three different aliquots. In the first aliquot, platelet aggregation was measured after platelet ...

  20. Naringin administration inhibits platelet aggregation and release by reducing blood cholesterol levels and the cytosolic free calcium concentration in hyperlipidemic rabbits

    OpenAIRE

    Xiao, Yang; LI, LAI-LAI; Guo, Jing-Jing; XU, WEN-PING; Wang, Yan-Yan; Wang, Yi

    2014-01-01

    This study investigated the effects of naringin on platelet aggregation and release in hyperlipidemic rabbits, and the underlying mechanisms. The safety of naringin was also investigated. The rabbits were orally administered 60, 30 or 15 mg/kg of naringin once a day for 14 days after being fed a high fat/cholesterol diet for four weeks. Following the two weeks of drug administration, the degree of platelet aggregation induced by arachidonic acid, adenosine diphosphate and collagen was signifi...

  1. Rac1-mediated signaling plays a central role in secretion-dependent platelet aggregation in human blood stimulated by atherosclerotic plaque

    OpenAIRE

    Khandoga Anna L; Pandey Dharmendra; Dwivedi Suman; Brandl Richard; Siess Wolfgang

    2010-01-01

    Abstract Background Platelet activation requires rapid remodeling of the actin cytoskeleton which is regulated by small GTP-binding proteins. By using the Rac1-specific inhibitor NSC23766, we have recently found that Rac1 is a central component of a signaling pathway that regulates dephosphorylation and activation of the actin-dynamising protein cofilin, dense and α-granule secretion, and subsequent aggregation of thrombin-stimulated washed platelets. Objectives To study whether NSC23766 inhi...

  2. Bleeding Disorders

    Science.gov (United States)

    ... as clotting factors. If you have a bleeding disorder, you either do not have enough platelets or ... don't work the way they should. Bleeding disorders can be the result of other diseases, such ...

  3. BMC Blood Disorders becomes BMC Hematology: evolving along with the hematology field

    OpenAIRE

    Chap, Christna

    2013-01-01

    This Editorial marks the launch of BMC Hematology, formerly known as BMC Blood Disorders, within the BMC series of journals published by BioMed Central. The scope of BMC Hematology encompasses basic, experimental and clinical research related to hematology. In this Editorial we will discuss the rationale behind this relaunch and how, as an open access journal providing unrestricted and free access to scientific and scholarly work, BMC Hematology will help disseminate research in the hematolog...

  4. Structural disproportions in regional medical standards in treatment of blood circulatory disorders

    OpenAIRE

    Sazanova G.Yu.

    2012-01-01

    The research goal is to consider the opinion of physicians about the financial medical assistance standards to patients with blood circulatory disorders. Materials and methods: 530 doctors of different specialties were interviewed. Some sociological and statistical methods were used in the study. Results: The majority of respondents (83%) considered that it was necessary to coordinate financial support of diagnostic and treatment expenditures with the standards of the regional program of rend...

  5. Platelet activation and platelet-leukocyte interaction in dogs naturally infected with Babesia rossi

    DEFF Research Database (Denmark)

    Goddard, Amelia; Leisewitz, Andrew L; Kristensen, Annemarie Thuri;

    2015-01-01

    Using flow cytometry, platelet-leukocyte aggregate (PLA) formation has previously been documented in dogs with a variety of systemic inflammatory disorders and immune-mediated haemolytic anaemia. Platelet activation and subsequent interaction between platelets and leukocytes are important for reg...

  6. Diagnostic tool for red blood cell membrane disorders: Assessment of a new generation ektacytometer.

    Science.gov (United States)

    Da Costa, Lydie; Suner, Ludovic; Galimand, Julie; Bonnel, Amandine; Pascreau, Tiffany; Couque, Nathalie; Fenneteau, Odile; Mohandas, Narla

    2016-01-01

    Inherited red blood cell (RBC) membrane disorders, such as hereditary spherocytosis, elliptocytosis and hereditary ovalocytosis, result from mutations in genes encoding various RBC membrane and skeletal proteins. The RBC membrane, a composite structure composed of a lipid bilayer linked to a spectrin/actin-based membrane skeleton, confers upon the RBC unique features of deformability and mechanical stability. The disease severity is primarily dependent on the extent of membrane surface area loss. RBC membrane disorders can be readily diagnosed by various laboratory approaches that include RBC cytology, flow cytometry, ektacytometry, electrophoresis of RBC membrane proteins and genetics. The reference technique for diagnosis of RBC membrane disorders is the osmotic gradient ektacytometry. However, in spite of its recognition as the reference technique, this technique is rarely used as a routine diagnosis tool for RBC membrane disorders due to its limited availability. This may soon change as a new generation of ektacytometer has been recently engineered. In this review, we describe the workflow of the samples shipped to our Hematology laboratory for RBC membrane disorder analysis and the data obtained for a large cohort of French patients presenting with RBC membrane disorders using a newly available version of the ektacytomer. PMID:26603718

  7. Donor demographic and laboratory predictors of single donor platelet yield

    Directory of Open Access Journals (Sweden)

    R. Arun

    2013-10-01

    Full Text Available Background: Platelet transfusions are essential to prevent morbidity and mortality in patients who are severely thrombocytopenic and are at risk of spontaneous bleeding. Platelets are currently obtained either by fractionation of whole blood or by platelet apheresis. The quality of single donor platelets (SDP in terms of yield influences platelet recovery in the recipient and allows prolonging intervals between transfusions. Material and Methods: Donor demographic and laboratory data were analyzed prior to performing plateletpheresis to identify donor factors that influence platelet yield. The study was conducted on 130 healthy, first-time plateletpheresis donors over a period of 4 years. The plateletpheresis procedures were performed using Fresenius Kabi COM.TEC and Hemonetics MCS plus separator. A relationship between pre-donation donor variables and yield of platelets was studied using the Pearson correlation. Results: The mean platelet yield was 3.160.62x1011 per unit. A positive correlation was observed between platelet yield and pre-donation platelet count, body mass index (BMI; Kg/m2 of the donor, while a negative correlation was observed between age and the platelet yield. Conclusion: Donor pre-donation platelet count, BMI and donor age influence platelet yield. Young healthy donors with a high platelet count and better BMI can give a better platelet yield in the SDP.

  8. Analysis on causes and countermeasures on pseudo - reduction of platelet count by blood cell analyzer%血细胞分析仪计数血小板假性减少原因分析及对策探讨

    Institute of Scientific and Technical Information of China (English)

    李惠卿; 赖馨; 蔡洁丹; 高洪丽; 唐万兵

    2014-01-01

    Objective To explore the causes and treatment strategies for pseudo - reduction of platelet count by blood cell analyzer. Methods A total of 351 blood samples for platelet count less than 100 × 109 / L measured by Beckman LH780 automatic blood cell analyzer were re - examined by handmade dilute count and smear staining for microscopy. They were divided into 5 groups according to platelet histogram,297 specimens with normal platelet histogram were allocated in group A;13 specimens with small platelet histogram in group B:11 specimens with large platelet histogram in group C:19 specimens with platelet aggregation histogram in group D,and 11 specimens with red cell fragments histo-gram in group E. The platelet count by blood cell analyzer and handmade dilute count were compared with smear staining examination under mi-croscopy for degree of coincidence. Results ① In comparison with handmade dilute count,the difference between group A and group B was not statistically significant( P ﹥ 0. 05),the difference between group C and group D was statistically significant( P < 0. 01),and the platelet count with blood cell analyzer was higher in group E,and the difference between group E and other groups was statistically significant( P < 0. 01). ②There was high degree of coincidence in results between handmade dilution count and smear staining examination under microscopy . Conclusion Platelet count by blood cell analyzer may be pseudo - reduced. In order to raise the accuracy of platelet count,the samples with abnormal platelet histogram need to be checked by handmade dilute count and smear staining examination under microscopy.%目的:探讨血细胞分析仪计数血小板(PLT)假性减少的原因及处理对策。方法对 Beckman LH780自动血细胞分析仪计数 PLT <100×109/ L 的351例样本进行手工稀释计数及涂片染色镜检,按血小板直方图类型分组,A组(正常血小板直方图):297例;B 组

  9. Protective Mechanisms of Guanosine from Solanum lycopersicum on Agonist-Induced Platelet Activation: Role of sCD40L

    Directory of Open Access Journals (Sweden)

    Iván Palomo

    2013-07-01

    Full Text Available In the past 30 years, only three natural products have been sources of new drugs with antiplatelet activity. In this study, we have demonstrated for the first time that guanosine from Solanum lycopersicum possesses antiplatelet (secretion, spreading, adhesion and aggregation activity in vitro and inhibition of platelet inflammatory mediator of atherosclerosis (sCD40L. According to ADP-induced platelet aggregation inhibiting, the total extract residue was fractionated by liquid chromatography/phase separation, affording an aqueous fraction. This fraction was subjected to repeated permeation over Sephadex LH-20 and semi-preparative TLC. The isolated compound finally obtained was identified as guanosine on the basis of its UV-spectra, HPLC and 1H-NMR data. Guanosine concentration dose-dependently (1 to 4 mmol/L inhibited platelet secretion and aggregation induced by ADP and collagen. Spread of human platelets on collagen in the presence of guanosine was fully inhibited. After incubation of whole blood with guanosine, the platelet adhesion and aggregation under flow conditions was inhibited concentration dependently (0.2 to 2 mmol/L. At the same concentrations that guanosine inhibits platelet aggregation, levels of sCD40L were significantly decreased. Guanosine is thus likely to exert significant protective effects in thromboembolic-related disorders by inhibiting platelet aggregation.

  10. Evaluation of whole blood zinc and copper levels in children with autism spectrum disorder.

    Science.gov (United States)

    Crăciun, Elena Cristina; Bjørklund, Geir; Tinkov, Alexey A; Urbina, Mauricio A; Skalny, Anatoly V; Rad, Florina; Dronca, Eleonora

    2016-08-01

    Zinc (Zn) and copper (Cu) are important trace elements for cognitive development and normal neurological functioning. Autism spectrum disorder (ASD) is a common neurological disorder, which has previously been associated with the levels of some trace elements in the blood. However, clinical data regarding the potential implication of Zn and Cu in patients with ASD are still insufficient. Therefore, the aim of the present study was to investigate the whole blood levels of Zn and Cu in a cohort of 28 children with ASD and 28 age- and gender-matched healthy controls. Whole blood Zn and Cu levels were assessed using inductively-coupled plasma-sector field mass spectrometry. Both in the control and in the ASD group, the values of whole blood Cu and Zn were characterized by a Gaussian distribution. The results indicate that the ASD children were characterized by ~10 % (p = 0.005) and ~12 % (p = 0.015) lower levels of whole blood Zn and Zn/Cu ratio, respectively, in comparison to controls. No significant difference in whole blood Cu was observed. However, Cu/Zn ratio was ~15 % (p = 0.008) higher in ASD children than that in the control ones. The results of the present study may be indicative of Zn deficiency in ASD children. Taking into account Zn-mediated up-regulation of metallothionein (MT) gene expression, these findings suggest a possible alteration in the functioning of the neuroprotective MT system. However, further investigations are required to test this hypothesis. PMID:27059237

  11. Lactadherin and clearance of platelet-derived microvesicles

    OpenAIRE

    Dasgupta, Swapan K.; Abdel-Monem, Hanan; Niravath, Polly; Le, Anhquyen; Bellera, Ricardo V.; Langlois, Kimberly; Nagata, Shigekazu; Rumbaut, Rolando E.; Thiagarajan, Perumal

    2009-01-01

    The transbilayer movement of phosphatidylserine from the inner to the outer leaflet of the membrane bilayer during platelet activation is associated with the release of procoagulant phosphatidylserine-rich small membrane vesicles called platelet-derived microvesicles. We tested the effect of lactadherin, which promotes the phagocytosis of phosphatidylserine-expressing lymphocytes and red blood cells, in the clearance of platelet microvesicles. Platelet-derived microvesicles were labeled with ...

  12. Clinical isolates of Enterococcus faecalis aggregate human platelets.

    OpenAIRE

    Rasmussen, Magnus; Johansson, Daniel; Karlsson Söbirk, Sara; Mörgelin, Matthias; Shannon, Oonagh

    2010-01-01

    Many endocarditis pathogens activate human platelets and this has been proposed to contribute to virulence. Here we report for the first time that many clinical isolates of Enterococcus faecalis, a common pathogen in infective endocarditis, aggregate human platelets. 84 isolates from human blood and urine were screened for their ability to aggregate platelets from four different donors. Platelet aggregation occurred for between 11 and 65 % of isolates depending on the donor. In one donor, a s...

  13. 定期无偿献血者NK细胞免疫功能的研究%The effect on NK cells immunity in regular whole blood and platelet donors

    Institute of Scientific and Technical Information of China (English)

    李桢; 熊文; 程良红; 唐斯; 王飞; 张艳艳

    2009-01-01

    目的 分析定期无偿全血捐献者、血小板捐献者的NK细胞数量以及细胞毒活性,评价定期捐血对机体NK细胞免疫功能的影响.方法 采用流式细胞术对三组人群(定期无偿全血、血小板和首次捐血者,后者为对照组)外周血中NK细胞群的数量进行分析.采用效/靶细胞混合培养的方法,计算出NK细胞对靶细胞的杀伤率.结果 全血捐献者NK细胞数量及其对靶细胞的杀伤率与对照组的差异无统计学意义(P>0.05);血小板捐献者NK细胞数量较对照组明显增高(P3个月),机体有足够的时间来恢复NK细胞数量及其细胞毒性,而血小板捐献者献血间隔期短,机体通过NK细胞数量的增加来调节由于其功能降低对机体造成的影响.%Objective To analysis NK cell count and cytotoxic activity in regular whole blood and platelet donors and to evaluate their immunity. Methods The NK cell count was analyzed by flow cytometer in peripheral blood in three crowds, viz free regular whole blood, platelet, and the first time whole blood donors. The last crow was the control group. The NK cell cytotoxic activity was analyzed by mixed culture of effecter cell/ target cell. Results The NK cell numbers and its anti-ratio to target cells in free regular whole blood donors had no significant differences with the control group(P>0.05). The platelet donors' NK cell numbers was significantly increased compared to control group(P 3 months), and have enough time to recovery their NK cell numbers and cytotoxicity. In contrast, platelet donation interval is shorter than other groups, so they must increase their NK cell numbers to regulate the effect caused by low function.

  14. Establishing biological reference intervals for novel platelet parameters (immature platelet fraction, high immature platelet fraction, platelet distribution width, platelet large cell ratio, platelet-X, plateletcrit, and platelet distribution width and their correlations among each other

    Directory of Open Access Journals (Sweden)

    Ritesh Sachdev

    2014-01-01

    Full Text Available Aims: This study aims to establish biological reference interval for novel platelet parameters. Settings and Design: A total of 945 healthy individuals, age ranges from 18 to 64 years (881 males and 64 females coming for voluntary blood donation from June to August 2012 (3 months were enrolled after exclusion of rejection criteria. Materials and Methods: The samples were assayed by running in complete blood count + reticulocyte mode on the Sysmex XE-2100 hematology analyzer and the reference interval for the population was calculated using Clinical and Laboratory Standards Institute guidelines. Statistical analysis used: Tests were performed using SPSS (Statistical Product and Service Solutions , developed by IBM corporation, version 13. Student t test and pearsons correlation analysis were also used. Results: The normal range for various parameters was platelet count: 150-520 × 10 3 /cu mm, immature platelet fraction (IPF: 0.3-8.7%, platelet distribution width (PDW: 8.3-25.0 fL, mean platelet volume (MPV: 8.6-15.5 fL, plateletcrit (PCT: 0.15-0.62%, high immature platelet fraction (H-IPF: 0.1-2.7%, platelet large cell ratio (P-LCR: 11.9-66.9% and platelet-X (PLT-X (ch: 11.0-22.0. Negative correlation was observed between platelet count (r = −0.468 to r = −0.531; P < 0.001 and PCT (r = −0.080 to r = −0.235; P < 0.05 to P < 0.001 with IPF, PDW, MPV, H-IPF, P-LCR, and platelet-X. IPF/H-IPF showed a positive correlation among them and also with PDW, MPV, P-LCR, platelet-X (r = +0.662 to r = +0.925; P < 0.001. Conclusions: These novel platelet parameters offer newer avenues in research and clinical use. Establishing biological reference interval for different platelet parameters would help determine true high and low values and help guide treatment decisions.

  15. The Effect of Hematocrit on Platelet Adhesion: Experiments and Simulations.

    Science.gov (United States)

    Spann, Andrew P; Campbell, James E; Fitzgibbon, Sean R; Rodriguez, Armando; Cap, Andrew P; Blackbourne, Lorne H; Shaqfeh, Eric S G

    2016-08-01

    The volume fraction of red blood cells (RBCs) in a capillary affects the degree to which platelets are promoted to marginate to near a vessel wall and form blood clots. In this work we investigate the relationship between RBC hematocrit and platelet adhesion activity. We perform experiments flowing blood samples through a microfluidic channel coated with type 1 collagen and observe the rate at which platelets adhere to the wall. We compare these results with three-dimensional boundary integral simulations of a suspension of RBCs and platelets in a periodic channel where platelets can adhere to the wall. In both cases, we find that the rate of platelet adhesion varies greatly with the RBC hematocrit. We observe that the relative decrease in platelet activity as hematocrit falls shows a similar profile for simulation and experiment. PMID:27508441

  16. Concentration of platelets and growth factors in platelet-rich plasma from Goettingen minipigs

    OpenAIRE

    Jungbluth, P; Grassmann, JP; Thelen, S; Wild, M.; Sager, M; Windolf, J.; M Hakimi

    2014-01-01

    In minipigs little is known about the concentration of growth factors in plasma, despite their major role in several patho-physiological processes such as healing of fractures. This prompted us to study the concentration of platelets and selected growth factors in plasma and platelet-rich plasma (PRP) preparation of sixteen Goettingen minipigs. Platelet concentrations increased significantly in PRP in comparison to native blood plasma. Generally, significant increase in the concentration of a...

  17. Dual roles for hepatic lectin receptors in the clearance of chilled platelets

    DEFF Research Database (Denmark)

    Rumjantseva, Viktoria; Grewal, Prabhjit K; Wandall, Hans H;

    2009-01-01

    Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta......-Morell receptor binding, become increasingly involved in platelet removal. Macrophages rapidly removed a large fraction of transfused platelets independent of their storage conditions. With prolonged platelet chilling, hepatocyte-dependent clearance further diminishes platelet recovery and survival after...... transfusion. Inhibition of chilled platelet clearance by both beta(2) integrin and Ashwell-Morell receptors may afford a potentially simple method for storing platelets in the cold....

  18. Release of angiogenesis regulatory proteins from platelet alpha granules: modulation of physiologic and pathologic angiogenesis

    OpenAIRE

    Battinelli, Elisabeth M.; Markens, Beth A.; Italiano, Joseph E.

    2011-01-01

    An association between platelets, angiogenesis, and cancer has long been recognized, but the mechanisms linking them remains unclear. Platelets regulate new blood vessel growth through numerous stimulators and inhibitors of angiogenesis by several pathways, including differential exocytosis of angiogenesis regulators. Herein, we investigated the differential release of angiogenesis stimulators and inhibitors from platelets. Activation of human platelets with adenosine diphosphate (ADP) stimul...

  19. Evaluation of the response of cortisol, corticotropin and blood platelets kinetics after laparoscopic and open cholecystectomy Avaliação da resposta do cortisol, da corticotropina e da cinética das plaquetas após colecistectomias laparoscópica e aberta

    OpenAIRE

    Eduardo Crema; Elisangela Neto Ribeiro; Ana Marcela Hial; Juverson Terra Alves Júnior; Ricardo Pastore; Alex Augusto Silva

    2005-01-01

    PURPOSE: To compare the behavior of serum cortisol and ACTH levels and platelet kinetics after laparoscopic and open cholecystectomy. METHODS: In this prospective study, 31 patients with symptomatic cholelithiasis submitted to elective cholecystectomy, 17 by the laparoscopic route and 14 by the open route, were compared. Peripheral blood samples were collected on admission of the patient, during anesthetic induction, and 2, 6, 12, 24 and 48 hours after the surgical incision. Platelets were co...

  20. The caspase-3 inhibitor (peptide Z-DEVD-FMK) affects the survival and function of platelets in platelet concentrate during storage

    OpenAIRE

    Shiri, Reza; Yari, Fatemeh; Ahmadinejad, Minoo; Vaeli, Shahram; Tabatabaei, Mohammad Reza

    2014-01-01

    Background Although apoptosis occurs in nucleated cells, studies show that this event also occurs in some anucleated cells such as platelets. During storage of platelets, the viability of platelets decreased, storage lesions were observed, and cells underwent apoptosis. We investigated the effects of caspase-3 inhibitor on the survival and function of platelets after different periods of storage. Methods Platelet concentrates were obtained from the Iranian Blood Transfusion Organization in pl...

  1. Evaluation of Peripheral Blood Circulation Disorder in Scleroderma Patients Using an Optical Sensor with a Pressurization Mechanism

    Science.gov (United States)

    Yamakoshi, Yoshiki

    2016-01-01

    Blood circulation function of peripheral blood vessels in skin dermis was evaluated employing an optical sensor with a pressurization mechanism using the blood outflow and reflow characteristics. The device contains a light source and an optical sensor. When applied to the skin surface, it first exerts the primary pressure (higher than the systolic blood pressure), causing an outflow of blood from the dermal peripheral blood vessels. After two heartbeats, the pressure is lowered (secondary pressure) and blood reflows into the peripheral blood vessels. Hemoglobin concentration, which changes during blood outflow and reflow, is derived from the received light intensity using the Beer–Lambert law. This method was evaluated in 26 healthy female volunteers and 26 female scleroderma patients. In order to evaluate the blood circulation function of the peripheral blood vessels of scleroderma patients, pressurization sequence which consists of primary pressure followed by secondary pressure was adopted. Blood reflow during the first heartbeat period after applying the secondary pressure of 40mmHg was (mean±SD) 0.059±0.05%mm for scleroderma patients and 0.173±0.104%mm for healthy volunteers. Blood reflow was significantly lower in scleroderma patients than in healthy volunteers (p<0.05). This result indicates that the information necessary for assessing blood circulation disorder of peripheral blood vessels in scleroderma patients is objectively obtained by the proposed method. PMID:27479094

  2. Blood Clotting and Pregnancy

    Medline Plus

    Full Text Available ... Blood Basics Blood Disorders Anemia Bleeding Disorders Blood Cancers Blood Clots Blood Clotting and Pregnancy Clots and ... Increased maternal age Other medical illness (e.g., cancer, infection) back to top How are Blood Clots ...

  3. Platelet satellitism: an Infrequent cause of spurious thrombocytopenia

    International Nuclear Information System (INIS)

    Platelet adherence to Neutrophilic leucocytes or so called 'Platelet satellitism' is an infrequent phenomenon. This finding was observed in a healthy person undergoing routine checkup. Multiple blood smears prepared from peripheral blood collected in Ethylene Diamine Tetra acetic Acid (EDTA) showed evidence of platelet satellitism with the Neutrophils only. Adherence was not observed with any other cell type. Platlet satellitism totally disappeared when samples were collected in heparin or tri-sodium citrate. (author)

  4. Brief Report: Whole Blood Serotonin Levels and Gastrointestinal Symptoms in Autism Spectrum Disorder

    Science.gov (United States)

    Marler, Sarah; Ferguson, Bradley J.; Lee, Evon Batey; Peters, Brittany; Williams, Kent C.; McDonnell, Erin; Macklin, Eric A.; Levitt, Pat; Gillespie, Catherine Hagan; Anderson, George M.; Margolis, Kara Gross; Beversdorf, David Q.; Veenstra-VanderWeele, Jeremy

    2016-01-01

    Elevated whole blood serotonin levels are observed in more than 25 % of children with autism spectrum disorder (ASD). Co-occurring gastrointestinal (GI) symptoms are also common in ASD but have not previously been examined in relationship with hyperserotonemia, despite the synthesis of serotonin in the gut. In 82 children and adolescents with ASD, we observed a correlation between a quantitative measure of lower GI symptoms and whole blood serotonin levels. No significant association was seen between functional constipation diagnosis and serotonin levels in the hyperserotonemia range, suggesting that this correlation is not driven by a single subgroup. More specific assessment of gut function, including the microbiome, will be necessary to evaluate the contribution of gut physiology to serotonin levels in ASD. PMID:26527110

  5. A study on regional cerebral blood flow at rest and stress state in anxiety disorder patients

    International Nuclear Information System (INIS)

    Objective: To investigate he characteristics of rest and stress regional cerebral blood flow (rCBF) in naive anxiety disorder patients. Methods: Twenty naive anxiety disorder patients were enrolled in the study with twenty healthy volunteers as controls. The rest and stress 99Tcm-ethylene cystein dimer (ECD) SPECT were performed separately at 2 consecutive days, Raven reasoning test was used as a stressor. Results: 1) Compared to the healthy controls, the patients' rest rCBF of the frontal lobe, temporal lobe, thalamus and basal ganglia were significantly lower (P<0.05 and 0.01). 2)The patients' stress rCBF of the frontal lobe, temporal lobe, part occipital lobe, part parietal lobe, thalamus and basal ganglia were significantly lower compared to the healthy controls' (P<0.05 and 0.01). 3) Opposite to the healthy controls, the rCBF of patients increased significantly after stressor simulating. Conclusions: The hypofunction of frontal lobe, temporal lobe, thalamus and basal ganglia may exist in naive anxiety disorder patients. The abnormal rCBF of patients after simulating may be one of the characteristics of anxiety disorder

  6. Peripheral whole blood microRNA alterations in major depression and bipolar disorder.

    Science.gov (United States)

    Maffioletti, Elisabetta; Cattaneo, Annamaria; Rosso, Gianluca; Maina, Giuseppe; Maj, Carlo; Gennarelli, Massimo; Tardito, Daniela; Bocchio-Chiavetto, Luisella

    2016-08-01

    Major depression (MD) and bipolar disorder (BD) are severe and potentially life-threating mood disorders whose etiology is to date not completely understood. MicroRNAs (miRNAs) are small non-coding RNAs that regulate protein synthesis post-transcriptionally by base-pairing to target gene mRNAs. Growing evidence indicated that miRNAs might play a key role in the pathogenesis of neuropsychiatric disorders and in the action of psychotropic drugs. On these bases, in this study we evaluated the expression levels of 1733 mature miRNAs annotated in miRBase v.17, through a microarray technique, in the blood of 20 MD and 20 BD patients and 20 healthy controls, in order to identify putative miRNA signatures associated with mood disorders. We found that 5 miRNAs (hsa-let-7a-5p, hsa-let-7d-5p, hsa-let-7f-5p, hsa-miR-24-3p and hsa-miR-425-3p) were specifically altered in MD patients and 5 (hsa-miR-140-3p, hsa-miR-30d-5p, hsa-miR-330-5p, hsa-miR-378a-5p and hsa-miR-21-3p) in BD patients, whereas 2 miRNAs (hsa-miR-330-3p and hsa-miR-345-5p) were dysregulated in both the diseases. The bioinformatic prediction of the genes targeted by the altered miRNAs revealed the possible involvement of neural pathways relevant for psychiatric disorders. In conclusion, the observed results indicate a dysregulation of miRNA blood expression in mood disorders and could indicate new avenues for a better understanding of their pathogenetic mechanisms. The identified alterations may represent potential peripheral biomarkers to be complemented with other clinical and biological features for the improvement of diagnostic accuracy. PMID:27152760

  7. Spurious automated platelet count. Enumeration of yeast forms as platelets by the cell-DYN 4000.

    Science.gov (United States)

    Latif, Shahnila; Veillon, Diana M; Brown, Donald; Kaltenbach, Jenny; Curry, Sherry; Linscott, Andrea J; Oberle, Arnold; Cotelingam, James D

    2003-12-01

    We recently encountered a patient with thrombocytopenia secondary to multiple drug therapy, disseminated prostatic adenocarcinoma, and sepsis who had a sudden decrease in his platelet count as enumerated by the Cell-DYN 4000 hematology analyzer (Abbott Diagnostics, Santa Clara, CA). A manual platelet count performed thereafter was even lower. The etiology of the spurious platelet count was clarified when numerous yeast forms were observed on routine microscopy of the peripheral blood smear. Subsequently, these organisms were identified as Candida glabrata from a positive blood culture (BACTEC 9240, Becton Dickinson, Cockeysville, MD). To our knowledge, this is the first report of spurious enumeration of yeast forms as platelets in an automated hematology system. The principle underlying platelet enumeration by the Cell-DYN 4000 system and other hematology analyzers and the value of microscopy on peripheral smears with unexpected CBC count results are discussed. PMID:14671977

  8. Determination of serum aluminum, platelet aggregation and lipid peroxidation in hemodialyzed patients

    Directory of Open Access Journals (Sweden)

    T.J.C. Neiva

    2002-03-01

    Full Text Available Aluminum (Al3+ overload is frequently associated with lipid peroxidation and neurological disorders. Aluminum accumulation is also reported to be related to renal impairment, anemia and other clinical complications in hemodialysis patients. The aim of the present study was to determine the degree of lipid peroxidation, platelet aggregation and serum aluminum in patients receiving regular hemodialytic treatment. The level of plasma lipid peroxidation was evaluated on the basis of thiobarbituric acid reactive substances (TBARS. Mean platelet peroxidation in patients undergoing hemodialysis was significantly higher than in normal controls (2.7 ± 0.03 vs 1.8 ± 0.06 nmol/l, P<0.05. Platelet aggregation and serum aluminum levels were determined by a turbidimetric method and atomic absorption spectrophotometry, respectively. Serum aluminum was significantly higher in patients than in normal controls (44.5 ± 29 vs 10.8 ± 2.5 µg/l, P<0.05. Human blood platelets were stimulated with collagen (2.2 µg/ml, adenosine diphosphate (6 µM and epinephrine (6 µM and showed reduced function with the three agonists utilized. No correlation between aluminum levels and platelet aggregation or between aluminum and peroxidation was observed in hemodialyzed patients.

  9. Platelets as immune mediators: Their role in host defense responses and sepsis

    OpenAIRE

    Li, Zhenyu; Yang, Fanmuyi; Dunn, Steve; Gross, A. Kendall; Smyth, Susan S.

    2010-01-01

    Platelets occupy a central role at the interface between thrombosis and inflammation. At sites of vascular damage, adherent platelets physically and functionally interact with circulating leukocytes. Activated platelets release soluble factors into circulation that may have local and systemic effects on blood and vascular cells. Platelets can also interact with a wide variety of microbial pathogens. Emerging evidence from animal models suggests that platelets may participate in a wide variety...

  10. Disabled-2 regulates platelet heterotypic and homotypic aggregation through sulfatide binding

    OpenAIRE

    Welsh, John Douglas

    2010-01-01

    At the site of vascular injury platelet aggregation serves to stem blood flow, initiate the inflammatory response, and stimulate wound healing. Platelets become stimulated, release their granule contents, and become adherent to one another. Platelet granules contain important clotting factors and regulators of aggregation. Disabled-2 (Dab2) is a negative regulator of platelet aggregation released from platelet α-granules. Dab2 binds to the αIIbβ3 integrin, through the PTB domain, and b...

  11. The Study of Platelet Volume Indices in Platelet Aphaeresis Procedure: An Experience Of 271 Platelet Aphaeresis Procedures

    Directory of Open Access Journals (Sweden)

    Arpit C Patel

    2015-09-01

    Full Text Available Background: Platelet activity can be assessed by platelet volume indices like MPV, PDW and P-LCR. Aim: To develop an approach in blood bank professional, a habit of looking at platelet indices in hematology analyzer report of aphaeresis donors and QC samples of platelet aphaeresis products. Methods and materials: A retrospective data analysis was done for 271 platelet aphaeresis procedures conducted on CS3000 plus with AMS cell separator, Fenwal, USA and COM.TEC, Fresenius Kabi, Germany. Samples of the donors were collected before aphaeresis and 1 to 2 ml sample from each bag was collected in the satellite pouch attached to bag and analysis was done on day 0 and day 7. Platelet parameters were measured on automated hematology analyzers SYSMEX KX-21 and Horiba Micros 60.Statistical analysis: Statistical analysis was done by calculating and lsquo;r value' and a paired t test at 95 % confidence interval. A P value of <0.05 was taken as significant. Results: The mean platelet yield was 3.39+/-0.88 x 1011/unit. The platelet yield correlated negatively with MPV, PDW and PLCR (r value -0.224, -0.045 and -0.159 respectively for correlation between MPV, PDW and PLCR with the yield, P <0.0001.The mean values of PVI of SDP were significantly smaller than that of donor pre-donation samples (paired t test P value < 0.05.The size of stored single donor platelet on day 7 were significantly larger than that of day 0 (P value < 0.05. Conclusion: The platelet indices are useful to study - selectively smaller platelet separation by automated cell separators, storage lesions and yield prediction. [Natl J Med Res 2015; 5(3.000: 207-210

  12. Changes in Regional Cerebral Blood Flow with Cognitive Behavioral Therapy in the Treatment of Panic Disorder

    Energy Technology Data Exchange (ETDEWEB)

    Won, K. S.; Jun, S. K.; Kim, J. B.; Jang, E. J. [College of Medicine, Univ. of Kyemyoung, Taegu (Korea, Republic of)

    2003-07-01

    This study attempted to prospectively investigate changes in regional cerebral blood flow (rCBF) on SPECT and clinical response to cognitive behavioral therapy (CBT) in patients with panic disorder with (PDA) and without (PD) agoraphobia. Using 99mTc-ECD brain SPECT, we assessed brain perfusion in 5 out patients at rest before and after CBT. The subjects received 12 weekly sessions of CBT. Subjects were assessed by Agoraphobic Cognitions Questionnaire, Body Sensations Questionnaire, Beck Anxiety Inventory, Anxiety Sensitivity Index, Beck Depression Inventory-II, Panic Disorder Severity Scale (PDSS) and clinical global improvement (CGI) scale measurement were used as outcome measures. Patients were considered responders to CBT if they are much or very much improved on CGI scale and have a PDSS score at least 30% below their baseline. The scans were statistically analyzed by using statistical parametric mapping (SPM99). The baseline scans were compared to the post-CBT scans by using the statistics option multi subject, different conditions. Of 5 subjects 4 were male, 3 diagnosed PDA, and 4 on anti-anxiety medication. All of the subjects were classified as CBT responders. Their mean pretreatment and posttreatment PDSS were 17.4 (SD=8.2) and 4.2 (SD=3.1), respectively. The results of SPM analysis showed a significant decrease in blood flow after CBT in the thalamus bilaterally and right middle frontal gyrus (Brodmann's area 6). All results were thresholded at an uncorrected p<0.001 (for voxel height) and a corrected p<0.04 (for spatial extent). These preliminary data suggest that SPM analysis of 99mTc-ECD brain SPECT can reveal the change of rCBF in patient with panic disorder before and after CBT and the CBT effect may be associated with limbic and thalamic networks. However this study was a short trial with small number of subjects. Further studies with larger patient cohorts are needed.

  13. Changes in Regional Cerebral Blood Flow with Cognitive Behavioral Therapy in the Treatment of Panic Disorder

    International Nuclear Information System (INIS)

    This study attempted to prospectively investigate changes in regional cerebral blood flow (rCBF) on SPECT and clinical response to cognitive behavioral therapy (CBT) in patients with panic disorder with (PDA) and without (PD) agoraphobia. Using 99mTc-ECD brain SPECT, we assessed brain perfusion in 5 out patients at rest before and after CBT. The subjects received 12 weekly sessions of CBT. Subjects were assessed by Agoraphobic Cognitions Questionnaire, Body Sensations Questionnaire, Beck Anxiety Inventory, Anxiety Sensitivity Index, Beck Depression Inventory-II, Panic Disorder Severity Scale (PDSS) and clinical global improvement (CGI) scale measurement were used as outcome measures. Patients were considered responders to CBT if they are much or very much improved on CGI scale and have a PDSS score at least 30% below their baseline. The scans were statistically analyzed by using statistical parametric mapping (SPM99). The baseline scans were compared to the post-CBT scans by using the statistics option multi subject, different conditions. Of 5 subjects 4 were male, 3 diagnosed PDA, and 4 on anti-anxiety medication. All of the subjects were classified as CBT responders. Their mean pretreatment and posttreatment PDSS were 17.4 (SD=8.2) and 4.2 (SD=3.1), respectively. The results of SPM analysis showed a significant decrease in blood flow after CBT in the thalamus bilaterally and right middle frontal gyrus (Brodmann's area 6). All results were thresholded at an uncorrected p<0.001 (for voxel height) and a corrected p<0.04 (for spatial extent). These preliminary data suggest that SPM analysis of 99mTc-ECD brain SPECT can reveal the change of rCBF in patient with panic disorder before and after CBT and the CBT effect may be associated with limbic and thalamic networks. However this study was a short trial with small number of subjects. Further studies with larger patient cohorts are needed

  14. Platelet function in brown bear (Ursus arctos compared to man

    Directory of Open Access Journals (Sweden)

    Särndahl Eva

    2010-06-01

    Full Text Available Abstract Background Information on hemostasis and platelet function in brown bear (Ursus arctos is of importance for understanding the physiological, protective changes during hibernation. Objective The study objective was to document platelet activity values in brown bears shortly after leaving the den and compare them to platelet function in healthy humans. Methods Blood was drawn from immobilized wild brown bears 7-10 days after leaving the den in mid April. Blood samples from healthy human adults before and after clopidogrel and acetylsalicylic acid administration served as control. We analyzed blood samples by standard blood testing and platelet aggregation was quantified after stimulation with various agonists using multiple electrode aggregometry within 3 hours of sampling. Results Blood samples were collected from 6 bears (3 females between 1 and 16 years old and from 10 healthy humans. Results of adenosine diphosphate, aspirin, and thrombin receptor activating peptide tests in bears were all half or less of those in humans. Platelet and white blood cell counts did not differ between species but brown bears had more and smaller red blood cells compared with humans. Conclusion Using three different tests, we conclude that platelet function is lower in brown bears compared to humans. Our findings represent the first descriptive study on platelet function in brown bears and may contribute to explain how bears can endure denning without obvious thrombus building. However, the possibility that our findings reflect test-dependent and not true biological variations in platelet reactivity needs further studies.

  15. Platelets and galectins

    OpenAIRE

    Schattner, Mirta

    2014-01-01

    A major function of platelets is keeping the vascular system intact. Platelet activation at sites of vascular injury leads to the formation of a hemostatic plug. Activation of platelets is therefore crucial for normal hemostasis; however, uncontrolled platelet activation may also lead to the formation of occlusive thrombi that can cause ischemic events. Although they are essential for proper hemostasis, platelet function extends to physiologic processes such as tissue repair, wound remodeling...

  16. Breaking the mold: transcription factors in the anucleate platelet and platelet-derived microparticles

    Directory of Open Access Journals (Sweden)

    Katie L Lannan

    2015-02-01

    Full Text Available Platelets are small anucleate blood cells derived from megakaryocytes. In addition to their pivotal roles in hemostasis, platelets are the smallest, yet most abundant, immune cell and regulate inflammation, immunity, and disease progression. Although platelets lack DNA, and thus no functional transcriptional activities, they are nonetheless rich sources of RNAs, possess an intact spliceosome, and are thus capable of synthesizing proteins. Previously, it was thought that platelet RNAs and translational machinery were remnants from the megakaryocyte. We now know that the initial description of platelets as cellular fragments is an antiquated notion, as mounting evidence suggests otherwise. Therefore, it is reasonable to hypothesize that platelet transcription factors are not vestigial remnants from megakaryoctes, but have important, if only partly understood functions. Proteins play multiple cellular roles to minimize energy expenditure for maximum cellular function; thus, the same can be expected for transcription factors. In fact, numerous transcription factors have non-genomic roles, both in platelets and in nucleated cells. Our lab and others have discovered the presence and nongenomic roles of transcription factors in platelets, such as the nuclear factor kappa β (NFκB family of proteins and peroxisome proliferator activated receptor gamma (PPARγ. In addition to numerous roles in regulating platelet activation, functional transcription factors can be transferred to vascular and immune cells through platelet microparticles. This method of transcellular delivery of key immune molecules may be a vital mechanism by which platelet transcription factors regulate inflammation and immunity. At the very least, platelets are an ideal model cell to dissect out the nongenomic roles of transcription factors in nucleated cells. There is abundant evidence to suggest that transcription factors in platelets play key roles in regulating inflammatory and

  17. A Novel Platelet Concentrate: Titanium-Prepared Platelet-Rich Fibrin

    OpenAIRE

    Mustafa Tunalı; Hakan Özdemir; Zafer Küçükodacı; Serhan Akman; Emre Yaprak; Hülya Toker; Erhan Fıratlı

    2014-01-01

    We developed a new product called titanium-prepared platelet-rich fibrin (T-PRF). The T-PRF method is based on the hypothesis that titanium may be more effective in activating platelets than the silica activators used with glass tubes in Chouckroun’s leukocyte- and platelet-rich fibrin (L-PRF) method. In this study, we aimed to define the structural characteristics of T-PRF and compare it with L-PRF. Blood samples were collected from 10 healthy male volunteers. The blood samples were drawn us...

  18. Evaluation of platelet thromboxane radioimmunoassay method to measure platelet life-span: Comparison with /sup 111/indium-platelet method

    International Nuclear Information System (INIS)

    The platelet activation during radiolabeling in vitro with Cr-51 and In-111 may affect the platelet life-span (PLS) in vivo. A new RIA method to measure PLS is being evaluated. Aspirin inhibits platelet thromboxane (TxA/sub 2/) by acetylating cyclooxygenase. The time required for the TxA/sub 2/ levels to return towards control values depends on the rate of new platelets entering circulation and is a measure of PLS. A single dose of aspirin (150mg) was given to 5 normal human subjects. Blood samples were collected for 2 days before aspirin and daily for 10 days. TxA/sub 2/ production in response to endogenous thrombin was studied by allowing 1 ml blood sample to clot at 370C for 90 min. Serum TxB/sub 2/ (stable breakdown product of Tx-A/sub 2/) levels determined by RIA technique. The plot of TxB/sub 2/ levels (% control) against time showed a gradual increase. The PLS calculated by linear regression analysis assuming a 2-day lag period before cyclooxygenase recovery is 9.7 +- 2.37. In the same 5 subjects, platelets from a 50ml blood sample were labeled with /sup 111/In-tropolone in 2 ml autologous plasma. Starting at 1 hr after injection of labeled platelets, 10 blood samples were obtained over a 8 day period. The PLS calculated based on a linear regression analysis is 10.2 +. 1.4. The PLS measured from the rate of platelet disappearance from circulation and the rate of platelet regeneration into circulation are quite comparable in normal subjects. TxA/sub 2/ regeneration RIA may provide a method to measure PLS without administering radioactivity to patient

  19. Improving platelet transfusion safety: biomedical and technical considerations.

    Science.gov (United States)

    Garraud, Olivier; Cognasse, Fabrice; Tissot, Jean-Daniel; Chavarin, Patricia; Laperche, Syria; Morel, Pascal; Lefrère, Jean-Jacques; Pozzetto, Bruno; Lozano, Miguel; Blumberg, Neil; Osselaer, Jean-Claude

    2016-03-01

    Platelet concentrates account for near 10% of all labile blood components but are responsible for more than 25% of the reported adverse events. Besides factors related to patients themselves, who may be particularly at risk of side effects because of their underlying illness, there are aspects of platelet collection and storage that predispose to adverse events. Platelets for transfusion are strongly activated by collection through disposal equipment, which can stress the cells, and by preservation at 22 °C with rotation or rocking, which likewise leads to platelet activation, perhaps more so than storage at 4 °C. Lastly, platelets constitutively possess a very large number of bioactive components that may elicit pro-inflammatory reactions when infused into a patient. This review aims to describe approaches that may be crucial to minimising side effects while optimising safety and quality. We suggest that platelet transfusion is complex, in part because of the complexity of the "material" itself: platelets are highly versatile cells and the transfusion process adds a myriad of variables that present many challenges for preserving basal platelet function and preventing dysfunctional activation of the platelets. The review also presents information showing--after years of exhaustive haemovigilance--that whole blood buffy coat pooled platelet components are extremely safe compared to the gold standard (i.e. apheresis platelet components), both in terms of acquired infections and of immunological/inflammatory hazards. PMID:26674828

  20. Blood Clotting and Pregnancy

    Medline Plus

    Full Text Available ... About Awards Membership ASH Foundation Global Programs Newsroom facebook twitter youtube linkedin Research In This Section Agenda ... View all publications For Patients Blood Basics Blood Disorders Anemia Bleeding Disorders Blood Cancers Blood Clots Blood ...

  1. Triggering by Paf-acether and adrenaline of cyclo-oxygenase-independent platelet aggregation.

    OpenAIRE

    Fouque, F.; Vargaftig, B B

    1984-01-01

    Platelet-activating factor (Paf-acether, 1-alkyl-2-acetyl-sn-glycero-3-phosphorylcholine) induced full aggregation and a limited release reaction of human platelets in plasma or in blood. Cyclo-oxygenase inhibition with aspirin only reduced aggregation when induced by threshold amounts of Paf-acether, whereas higher concentrations surmounted inhibition whether tested in citrated or in heparinized platelet-rich plasma or blood. Aspirin-induced inhibition of platelet secretion by Paf-acether wa...

  2. New 'ex vivo' radioisotopic method of quantitation of platelet deposition

    International Nuclear Information System (INIS)

    We have developed a sensitive and quantitative method of 'ex vivo' evaluation of platelet deposition on collagen strips, from rabbit Achilles tendon, superfused by flowing blood and applied it to four animal species, cat, rabbit, dog and pig. Autologous platelets were labeled with indium-111-tropolone, injected to the animal 24 hr before the superfusion and the number of deposited platelets was quantitated from the tendon gamma-radiation and the blood platelet count. We detected some platelet consumption with superfusion time when blood was reinfused entering the contralateral jugular vein after collagen contact but not if blood was discarded after the contact. Therefore, in order to have a more physiological animal model we decided to discard blood after superfusion of the tendon. In all species except for the cat there was a linear relationship between increase of platelet on the tendon and time of exposure to blood superfusion. The highest number of platelets deposited on the collagen was found in cats, the lowest in dogs. Ultrastructural analysis showed the platelets were deposited as aggregates after only 5 min of superfusion. (orig.)

  3. Reference intervals for platelet aggregation assessed by multiple electrode platelet aggregometry

    DEFF Research Database (Denmark)

    Rubak, Peter; Villadsen, Kirsten; Hvas, Anne-Mette

    2012-01-01

    Abstract Introduction Analyses of platelet aggregation in hirudin whole blood using Multiplate® was validated. Reference intervals for the most commonly used agonists were established, and the association between platelet aggregation, age, gender and haematological values was analysed. Material and...... methods We included 121 healthy individuals to establish reference intervals and six healthy individuals for evaluation of the day-to-day variation. Platelet aggregation was evaluated on hirudin whole blood employing Multiplate® induced by arachidonic acid, ADP, collagen and ristocetin (RISTOlow and...... < 0.0003), except RISTOlow (p = 0.05). A reference interval is presented as 95% confidence interval suitable for any age and both sex. Day-to-day variation was < 11% for all agonists except for RISTOlow. No association was found between platelet aggregation and haematocrit or red blood cell count...

  4. Regional cerebral blood flow and cognitive function in patients with obsessive-compulsive disorder

    Directory of Open Access Journals (Sweden)

    Huirong Guo

    2014-01-01

    Full Text Available Objective: To explore the relationship between regional cerebral blood flow (CBF and cognitive function in obsessive-compulsive disorder (OCD. Method: Single-photon emission computed tomography (SPECT was performed for 139 OCD patients and 139 controls, and the radioactivity rate (RAR was calculated. Cognitive function was assessed by the Wisconsin Card Sorting Test (WCST. Results: The RARs of the prefrontal, anterior temporal, and right occipital lobes were higher in patients than controls. For the WCST, correct and classification numbers were significantly lower, and errors and persistent errors were significantly higher in OCD patients. Right prefrontal lobe RAR was negatively correlated with correct numbers, right anterior temporal lobe RAR was positively correlated with errors, and the RARs of the right prefrontal lobe and left thalamus were positively correlated with persistent errors. Conclusion: OCD patients showed higher CBF in the prefrontal and anterior temporal lobes, suggesting that these areas may be related with cognitive impairment.

  5. Stiffening of Red Blood Cells Induced by Disordered Cytoskeleton Structures: A Joint Theory-experiment Study

    CERN Document Server

    Lai, Lipeng; Lim, Chwee Teck; Cao, Jianshu

    2015-01-01

    The functions and elasticities of the cell are largely related to the structures of the cytoskeletons underlying the lipid bi-layer. Among various cell types, the Red Blood Cell (RBC) possesses a relatively simple cytoskeletal structure. Underneath the membrane, the RBC cytoskeleton takes the form of a two dimensional triangular network, consisting of nodes of actins (and other proteins) and edges of spectrins. Recent experiments focusing on the malaria infected RBCs (iRBCs) showed that there is a correlation between the elongation of spectrins in the cytoskeletal network and the stiffening of the iRBCs. Here we rationalize the correlation between these two observations by combining the worm-like chain (WLC) model for single spectrins and the Effective Medium Theory (EMT) for the network elasticity. We specifically focus on how the disorders in the cytoskeletal network affect its macroscopic elasticity. Analytical and numerical solutions from our model reveal that the stiffness of the membrane increases with ...

  6. Post-transfusion purpura in an African-American man due to human platelet antigen-5b alloantibody: a case report

    Directory of Open Access Journals (Sweden)

    Lynce Filipa

    2012-12-01

    Full Text Available Abstract Introduction Post-transfusion purpura is a rare immunohematological disorder characterized by severe thrombocytopenia following transfusion of blood components and induced by an alloantibody against a donor platelet antigen. It occurs primarily in women sensitized by pregnancy and is most commonly caused by anti-human platelet antigen-1a antibodies. Here, we describe what we believe to be the first documented case of an African-American man who developed post-transfusion purpura due to an anti-human platelet antigen-5b alloantibody after receiving multiple blood products. Case presentation A 68-year-old African-American man initially admitted with atrial flutter was started on anticoagulation treatment, which was complicated by severe hematemesis. On days 4 and 5 of hospitalization, he received six units of packed red blood cells, and on days 4, 13 and 14 he received plasma. His platelet count began to drop on day 25 and on day 32 reached a nadir of 7 × 109/L. His platelet count increased after receiving intravenous immune globulin. An antibody with reactivity to human platelet antigen-5b was detected by a solid-phase enzyme-linked immunoassay. Our patient was homozygous for human platelet antigen-5a. Conclusion This case emphasizes the importance of including post-transfusion purpura in the differential diagnosis for both men and women with acute onset of thrombocytopenia following transfusion of blood products. The prompt recognition of this entity is crucial for initiation of the appropriate management.

  7. Radionuclide distribution following injection of 111indium-labelled platelets

    International Nuclear Information System (INIS)

    Platelets labelled with 111In displayed similar survival curves after incubation with 111In-oxine in plasma, plasma-saline and dextrose saline media. The use of autologous red cells to cushion platelets during high-speed centrifugation facilitated platelet resuspension without greatly affecting the duration of the labelling procedure. Quantitative scanning after reinjection of labelled platelets in haematologically normal subjects showed that, initially, splenic indium amounted to about 35% of the injected dose and hepatic indium about 12%; these levels rose only slightly over the subsequent duration of the platelet life span. Subtraction of the signal from indium in platelets thought to be normally pooled within the spleen from the total indium signal gave splenic indium uptake curves which reflected splenic platelet destruction. Initially, the sum of indium levels in spleen, liver and blood equalled 100% of the dose. Thereafter, the sum fell progressively at a rate thought to be approximately equal to the rate of bone marrow uptake. (author)

  8. Gut Microbial Metabolite TMAO Enhances Platelet Hyperreactivity and Thrombosis Risk.

    Science.gov (United States)

    Zhu, Weifei; Gregory, Jill C; Org, Elin; Buffa, Jennifer A; Gupta, Nilaksh; Wang, Zeneng; Li, Lin; Fu, Xiaoming; Wu, Yuping; Mehrabian, Margarete; Sartor, R Balfour; McIntyre, Thomas M; Silverstein, Roy L; Tang, W H Wilson; DiDonato, Joseph A; Brown, J Mark; Lusis, Aldons J; Hazen, Stanley L

    2016-03-24

    Normal platelet function is critical to blood hemostasis and maintenance of a closed circulatory system. Heightened platelet reactivity, however, is associated with cardiometabolic diseases and enhanced potential for thrombotic events. We now show gut microbes, through generation of trimethylamine N-oxide (TMAO), directly contribute to platelet hyperreactivity and enhanced thrombosis potential. Plasma TMAO levels in subjects (n > 4,000) independently predicted incident (3 years) thrombosis (heart attack, stroke) risk. Direct exposure of platelets to TMAO enhanced sub-maximal stimulus-dependent platelet activation from multiple agonists through augmented Ca(2+) release from intracellular stores. Animal model studies employing dietary choline or TMAO, germ-free mice, and microbial transplantation collectively confirm a role for gut microbiota and TMAO in modulating platelet hyperresponsiveness and thrombosis potential and identify microbial taxa associated with plasma TMAO and thrombosis potential. Collectively, the present results reveal a previously unrecognized mechanistic link between specific dietary nutrients, gut microbes, platelet function, and thrombosis risk. PMID:26972052

  9. Evaluation of platelet aggregation in platelet concentrates: storage implications

    Directory of Open Access Journals (Sweden)

    Neiva Teresinha J.C.

    2003-01-01

    Full Text Available The use of hemo-derivatives is nowadays a fundamentally important therapeutic modality in the exercise of medicine. Among the various hemo-components employed, we have the platelet concentrate (PC, indicated in cases of hemorrhagic disturbances. We previously showed that platelet function in blood donors is reduced in their screening phase and after the separation process of PCs. Currently, we are providing evidence for the existence of biochemical and functional changes in PC preparations stored for three days at temperatures of 20 ± 2 ºC. Platelet concentrates from 40 healthy donors, collected in CPD anticoagulant and PL-146 polyvinylchloride containers, were examined in order to determine the pH value, pCO2 ,pO2 and lactate concentrations. In addition, the aggregation of platelets with thrombin and collagen were examined to evaluate platelet function. A pH increase from 7.07 ± 0.04 to 7.36 ± 0.07 (p < 0.01 was observed. The pCO2 concentration decreased progressively from 69.2 ± 7.7 mmHg to 28.8 ± 6.2 mmHg (p < 0.001 during the storage period. In contrast, pO2 value increase from 103.4 ± 30.6 to 152.3 ± 24.6 mmHg (p < 0.001 was evidenced during the 48 hours of storage. The lactate concentration increased from 17.97 ± 5.2 to 57.21 ± 5.7 mg/dl (p < 0.001. Platelet aggregation using 0.25 U/ml-thrombin and 2.0 µg/ml-collagen showed significant hypofunction from 61.8 ± 2.7% to 24.8 ± 9.8% and 62.7±5.0 to 33.4± 6.2 (p < 0.001, respectively. We concluded that the evaluated biochemical parameters and the platelet function changed significantly when the platelets were kept under routine storage conditions.

  10. Dose response of surfactants to attenuate gas embolism related platelet aggregation

    Science.gov (United States)

    Eckmann, David M.; Eckmann, Yonaton Y.; Tomczyk, Nancy

    2014-03-01

    Intravascular gas embolism promotes blood clot formation, cellular activation, and adhesion events, particularly with platelets. Populating the interface with surfactants is a chemical-based intervention to reduce injury from gas embolism. We studied platelet activation and platelet aggregation, prominent adverse responses to blood contact with bubbles. We examined dose-response relationships for two chemically distinct surfactants to attenuate the rise in platelet function stimulated by exposure to microbubbles. Significant reduction in platelet aggregation and platelet activation occurred with increasing concentration of the surfactants, indicating presence of a saturable system. A population balance model for platelet aggregation in the presence of embolism bubbles and surfactants was developed. Monte Carlo simulations for platelet aggregation were performed. Results agree qualitatively with experimental findings. Surfactant dose-dependent reductions in platelet activation and aggregation indicate inhibition of the gas/liquid interface's ability to stimulate cellular activation mechanically.

  11. Entrapment of platelets in the penis during and after erection

    International Nuclear Information System (INIS)

    Because of the development of hypercoagulability and the deposition of fibrin in the penis during erection a study of the possible role of platelets in this process was undertaken. Platelets response was studied in 9 adult chacma baboons (Papio ursinus) using autologous in vitro indium-111-labelled platelets and sequential scintigraphy of the penis during erection. The blood pooling pattern was obtained using in vivo technetium-99m-labelled red cells in a similar investigation. A statistically significant retention of platelets occured during and after erection, wich could not be attributed to blood pooling (P < 0,05). Entrapment of platelets could lead to enhanced activation, and might play a significant role in hypercoagulability and fibrin deposition during erection. Therefore platelets could be an important factor in the pathogenesis of ageing impotence

  12. Synthesis, characterizations and applications of some nanomaterials (TiO2 and SiC nanostructured films, organized CNT structures, ZnO structures and CNT{blood platelet clusters)

    Indian Academy of Sciences (India)

    O N Srivastava; A Srivastava; D Dash; D P Singh; R M Yadava; P R Mishra; J Singh

    2005-10-01

    TiO2 nanostructured films have been synthesized by the hydrolysis of Ti[OCH(CH3)2]4 as the precursor. These films have been utilized for the dissociation of phenol contaminant in water. Free-standing nanostructured film of silicon carbide (SiC) has been synthesized, employing a simple and new route of spray pyrolysis technique utilizing a slurry of Si in hexane. Another study is done on organized carbon nanotube (CNT) structures. These are made in the form of hollow cylinders (50 mm length, 4 mm diameter and 1.5 mm wall thickness). These CNT-based cylinders are made of conventional CNT and bamboo-shaped CNT. The filtrations of heavy hydrocarbons and . coli bacteria from water have been carried out. In addition to this, ZnO nanostructures have also been studied. Another study concerns CNT-blood platelet clusters.

  13. Cardiac and vascular imaging with labeled platelets and leukocytes

    International Nuclear Information System (INIS)

    The contribution of platelets in atherosclerosis and thrombosis in animal models and in clinical studies has been quantified with 111In-platelet scintigraphy. New in vitro quantitative techniques have been developed using 111In-labeled platelets to determine the number of adherent platelets on deendothelialized surfaces of damaged vessel walls and synthetic vascular grafts. In vivo imaging techniques are semi-quantitative in nature; in these studies 111In radioactivity on thrombotic vessels or graft surfaces of iliac, femoral, or popliteal arteries is compared with contralateral vessels. Background 111In radioactivity in the circulating blood pool of venous and capillary networks and radioactivity in marrow decreases the sensitivity of these techniques. Subtraction of blood pool radioactivity with 99mTc-labeled autologous red cells and calculation of 111In radioactivity associated with platelet thrombus on vessel walls also have been performed for coronary, carotid, and femoral arteries. Although platelet concentrates are used frequently after open heart surgery (one to six per patient), consumption of platelets in the artificial lung or oxygenator, lysis of platelets during pumping, and suction of blood only recently have been quantified with the use of 111In-labeled platelets. These studies also demonstrated far less trauma to platelets with the use of a membrane rather than a bubble oxygenator. Further reduction in platelet consumption and trauma was observed with the use of prostacyclin, a short-acting drug with significant beneficial effect on platelet thrombus reduction and disaggregation of aggregated platelets. The role of polymorphonuclear leukocytes in inflammation, infection and myocardial infarction, and in vivo evaluation with 111In-leukocyte scintigraphy in animals and humans has been described

  14. Pegylated G-CSF Inhibits Blood Cell Depletion, Increases Platelets, Blocks Splenomegaly, and Improves Survival after Whole-Body Ionizing Irradiation but Not after Irradiation Combined with Burn

    Directory of Open Access Journals (Sweden)

    Juliann G. Kiang

    2014-01-01

    Full Text Available Exposure to ionizing radiation alone (radiation injury, RI or combined with traumatic tissue injury (radiation combined injury, CI is a crucial life-threatening factor in nuclear and radiological accidents. As demonstrated in animal models, CI results in greater mortality than RI. In our laboratory, we found that B6D2F1/J female mice exposed to 60Co-γ-photon radiation followed by 15% total-body-surface-area skin burns experienced an increment of 18% higher mortality over a 30-day observation period compared to irradiation alone; that was accompanied by severe cytopenia, thrombopenia, erythropenia, and anemia. At the 30th day after injury, neutrophils, lymphocytes, and platelets still remained very low in surviving RI and CI mice. In contrast, their RBC, hemoglobin, and hematocrit were similar to basal levels. Comparing CI and RI mice, only RI induced splenomegaly. Both RI and CI resulted in bone marrow cell depletion. It was observed that only the RI mice treated with pegylated G-CSF after RI resulted in 100% survival over the 30-day period, and pegylated G-CSF mitigated RI-induced body-weight loss and depletion of WBC and platelets. Peg-G-CSF treatment sustained RBC balance, hemoglobin levels, and hematocrits and inhibited splenomegaly after RI. The results suggest that pegylated G-CSF effectively sustained animal survival by mitigating radiation-induced cytopenia, thrombopenia, erythropenia, and anemia.

  15. N-Acetylcysteine potentiates inhibition of platelet aggregation by nitroglycerin.

    OpenAIRE

    Loscalzo, J

    1985-01-01

    Platelet aggregation is currently felt to play an important role in the pathogenesis of ischemic vascular disorders. The smooth muscle relaxant, nitroglycerin, has been shown to inhibit platelet aggregation in vitro, but at concentrations that were felt to be unattainable in vivo. Because the in vivo action of nitroglycerin on smooth muscle cells has been shown to depend on the presence of reduced cytosolic sulfhydryl groups, the inhibitory effect of nitroglycerin on platelet aggregation was ...

  16. Inhibition of platelet aggregation by transdermal glyceryl trinitrate.

    OpenAIRE

    R. Andrews; May, J. A.; Vickers, J.; Heptinstall, S

    1994-01-01

    OBJECTIVE--To determine the optimum conditions for the demonstration of an antiplatelet effect of nitric oxide and to use these conditions to elucidate the effects of a transdermal glyceryl trinitrate patch on platelet aggregation in normal volunteers. METHODS--An open prospective crossover study. The effects of nitric oxide on platelet aggregation in whole blood and platelet rich plasma as stimulated by adenosine diphosphate and U46619 was assessed in the presence and absence of iloprost and...

  17. Clinical Applications of Platelet-Rich Plasma in Patellar Tendinopathy

    OpenAIRE

    D. U. Jeong; C.-R. Lee; Lee, J.H.; Pak, J.; L.-W. Kang; B. C. Jeong; Lee, S. H.

    2014-01-01

    Platelet-rich plasma (PRP), a blood derivative with high concentrations of platelets, has been found to have high levels of autologous growth factors (GFs), such as transforming growth factor-β (TGF-β), platelet-derived growth factor (PDGF), fibroblastic growth factor (FGF), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). These GFs and other biological active proteins of PRP can promote tissue healing through the regulation of fibrosis and angiogenesis. Moreover,...

  18. Platelet Activation and Inhibition in Connection with Vascular Stents

    OpenAIRE

    Christensen, Kjeld

    2007-01-01

    This thesis describes the Chandler loop, which makes it possible to conduct studies in vitro of molecular and cellular interactions between whole blood and stents. It was possible to monitor activation and inhibition of the cascades systems, leukocytes and platelets by combining different platelet inhibitors and heparin coating of stents. The clinical study was performed on patients with ACS undergoing PCI and stent implantation. In this study platelet activation markers P-selectin, and αIIb/...

  19. Activated platelet chemiluminescence and presence of CD45+ platelets in patients with acute myocardial infarction.

    Science.gov (United States)

    Gabbasov, Zufar; Ivanova, Oxana; Kogan-Yasny, Victor; Ryzhkova, Evgeniya; Saburova, Olga; Vorobyeva, Inna; Vasilieva, Elena

    2014-01-01

    It has been found that in 15% of acute myocardial infarction patients' platelets generate reactive oxygen species that can be detected with luminol-enhanced chemiluminescence of platelet-rich plasma within 8-10 days after acute myocardial infarction. This increase in generate reactive oxygen species production coincides with the emergence of CD45(+) platelets. The ability of platelets to carry surface leukocyte antigen implies their participation in exchange of specific proteins in the course of acute myocardial infarction. Future studies of CD45(+) platelets in peripheral blood of acute myocardial infarction patients in association with generate reactive oxygen species production may provide a new insight into the complex mechanisms of cell-cell interactions associated with acute myocardial infarction. PMID:24102264

  20. Mild hypothermia does not attenuate platelet aggregation and may even increase ADP-stimulated platelet aggregation after clopidogrel treatment

    OpenAIRE

    Erlinge David; Högberg Carl; Braun Oscar Ö

    2009-01-01

    Abstract Background Mild hypothermia is currently standard of care for cardiac arrest patients in many hospitals and a common belief is that hypothermia attenuates platelet aggregation. We wanted to examine the effects of clopidogrel on platelet aggregation during hypothermia. Methods Platelet reactivity at 37°C and 33°C was evaluated by light transmission aggregometry and vasodilator-stimulated phosphoprotein (VASP) in blood from healthy volunteers before, and 24 hours after, a 600 mg loadin...

  1. Platelet adhesion studies on dipyridamole coated polyurethane surfaces

    Directory of Open Access Journals (Sweden)

    Aldenhoff Y. B.J.

    2003-06-01

    Full Text Available Surface modification of polyurethanes (PUs by covalent attachment of dipyridamole (Persantinregistered is known to reduce adherence of blood platelets upon exposure to human platelet rich plasma (PRP. This effect was investigated in further detail. First platelet adhesion under static conditions was studied with four different biomaterial surfaces: untreated PU, PU immobilised with conjugate molecule 1, PU immobilised with conjugate molecule 2, and PU immobilised with conjugate molecule 3. In PU immobilised with 1 dipyridamole is directly linked to the surface, in PU immobilised with 2 there is a short hydrophilic spacer chain in between the surface and the dipyridamole, while conjugate molecule 3 is merely the spacer chain. Scanning electron microscopy (SEM was used to characterise platelet adhesion from human PRP under static conditions, and fluorescence imaging microscopy was used to study platelet adhesion from whole blood under flow. SEM experiments encompassed both density measurements and analysis of the morphology of adherent platelets. In the static experiments the surface immobilised with 2 showed the lowest platelet adherence. No difference between the three modified surfaces emerged from the flow experiments. The surfaces were also incubated with washed blood platelets and labeled with Oregon-Green Annexin V. No capture of Oregon-Green Annexin V was seen, implying that the adhered platelets did not expose any phosphatidyl serine at their exteriour surface.

  2. Platelets aggregation in pathological conditions: role of local shear rates and platelet activation delay time.

    Science.gov (United States)

    Li, He; Zarif Khalili Yazdani, Alireza; Karniadakis, George

    2015-11-01

    Platelets play an essential role in the initiation and formation of a thrombus, however their detailed motion in blood vessels with complex geometries, such as in the aneurysmal vessel or stenotic vessel in atherosclerosis, has not been studied systematically. Here, we perform spectral element simulations (NEKTAR code) to obtain the 3D flow field in blood vessel with cavities, and we apply the force coupling method (FCM) to simulate the motion of platelets in blood flow. Specifically, simulations of platelets are performed in a 0.25 mm diameter circular blood vessel with 1 mm length. Corresponding coarse-grained molecular dynamics simulations are employed to provide input to the NEKTAR-FCM code. Simulations are conducted at several different Reynolds numbers (Re). An ellipsoid-shaped cavity is selected to intersect with the middle part of the circular vessel to represent the aneurysmal part of the blood vessel. Based on the simulation results, we quantify how the platelets motion and aggregation in the blood vessel cavities depend on Re, platelet activation delay time, and the geometry of the cavities.

  3. Platelets of patients with chronic kidney disease demonstrate deficient platelet reactivity in vitro

    Directory of Open Access Journals (Sweden)

    van Bladel Esther R

    2012-09-01

    Full Text Available Abstract Background In patients with chronic kidney disease studies focusing on platelet function and properties often are non-conclusive whereas only few studies use functional platelet tests. In this study we evaluated a recently developed functional flow cytometry based assay for the analysis of platelet function in chronic kidney disease. Methods Platelet reactivity was measured using flow cytometric analysis. Platelets in whole blood were triggered with different concentrations of agonists (TRAP, ADP, CRP. Platelet activation was quantified with staining for P-selectin, measuring the mean fluorescence intensity. Area under the curve and the concentration of half-maximal response were determined. Results We studied 23 patients with chronic kidney disease (9 patients with cardiorenal failure and 14 patients with end stage renal disease and 19 healthy controls. Expression of P-selectin on the platelet surface measured as mean fluorescence intensity was significantly less in chronic kidney disease patients compared to controls after maximal stimulation with TRAP (9.7 (7.9-10.8 vs. 11.4 (9.2-12.2, P = 0.032, ADP (1.6 (1.2-2.1 vs. 2.6 (1.9-3.5, P = 0.002 and CRP (9.2 (8.5-10.8 vs. 11.5 (9.5-12.9, P = 0.004. Also the area under the curve was significantly different. There was no significant difference in half-maximal response between both groups. Conclusion In this study we found that patients with chronic kidney disease show reduced platelet reactivity in response of ADP, TRAP and CRP compared to controls. These results contribute to our understanding of the aberrant platelet function observed in patients with chronic kidney disease and emphasize the significance of using functional whole blood platelet activation assays.

  4. Glycoprotein biosynthesis by human normal platelets

    International Nuclear Information System (INIS)

    Incorporation of radioactive Man, Gal, Fuc, Glc-N, and NANA into washed human normal platelets and endogenous glycoproteins has been found. Both parameters were time dependent. Analysis of hydrolyzed labeled glycoproteins by paper chromatography revealed that the radioactive monosaccharide incubated with the platelets had not been converted into other sugars. Acid hydrolysis demonstrates the presence of a glycosidic linkage. All the effort directed to the demonstration of the existence of a lipid-sugar intermediate in intact human platelets yielded negative results for Man and Glc-N used as precursors. The incorporation of these sugars into glycoproteins is insensitive to bacitracin, suggesting no involvement of lipid-linked saccharides in the synthesis of glycoproteins in human blood platelets. The absence of inhibition of the glycosylation process in the presence of cycloheximide suggests that the sugars are added to proteins present in the intact platelets. These results support the contention that glycoprotein biosynthesis in human blood platelets observed under our experimental conditions is effected through direct sugar nucleotide glycosylation

  5. Hepatic transformation of prostaglandin D2 to a new prostanoid, 9 alpha,11 beta-prostaglandin F2, that inhibits platelet aggregation and constricts blood vessels

    International Nuclear Information System (INIS)

    The metabolic transformation of tritium-labeled prostaglandin D2 ([3H]PGD2) was investigated in the isolated Tyrode's-perfused rabbit liver. One major product was isolated and identified in the perfusate as a new prostanoid. The structure of this metabolite was further confirmed by gas chromatography-mass spectrometry and chemical methods to be 9 alpha,11 beta,15-L-trihydroxyprosta-5-cis, 13-trans-dienoic acid, namely (9 alpha,11 beta-PGF2). This new prostanoid was found to be an inhibitor of platelet aggregation and to cause constriction of canine coronary artery strips. These results suggested that on passage through the hepatic circulation exogenous PGD2 is converted to 9 alpha,11 beta-PGF2, the latter having a biological profile which differs from that of PGD2 and PGF2 alpha

  6. Rapid in vitro biocompatibility assay of endovascular stents by flow cytometry using platelet activation and platelet-leukocyte aggregation.

    Science.gov (United States)

    Tárnok, A; Mahnke, A; Müller, M; Zotz, R J

    1999-02-15

    Clinical studies suggest that stent design and surface texture are responsible for differences in biocompatibility of metallic endovascular stents. A simple in vitro experimental setup was established to test stent-induced degree of platelet and leukocyte activation and platelet-leukocyte aggregation by flow cytometry. Heparin-coated tantalum stents and gold-coated and uncoated stainless steel stents were tested. Stents were implanted into silicone tubes and exposed to blood from healthy volunteers. Platelet and leukocyte activation and percentage of leukocyte-platelet aggregates were determined in a whole-blood assay by subsequent staining for activation-associated antigens (CD41a, CD42b, CD62p, and fibrinogen binding) and leukocyte antigens (CD14 and CD45) and flow cytometric analysis. Blood taken directly after venous puncture or exposed to the silicone tube alone was used as negative controls. Positive control was in vitro stimulation with thrombin receptor activating peptide (TRAP-6). Low degree of platelet activation and significant increase in monocyte- and neutrophil-platelet aggregation were observed in blood exposed to stents (P coated stents continuously induced less platelet activation and leukocyte-platelet aggregation than uncoated stainless steel stents of the same length and shorter stents of the same structure. Stent surface coating and texture plays a role in platelet and leukocyte activation and leukocyte-platelet aggregation. Using this simple in vitro assay and whole blood and flow cytometry, it seems possible to differentiate stents by their potency to activate platelets and/or leukocytes. This assay could be applied for improving the biocompatibility of coronary stents. PMID:10088974

  7. Platelet and growth factor concentrations in activated platelet-rich plasma: a comparison of seven commercial separation systems.

    Science.gov (United States)

    Kushida, Satoshi; Kakudo, Natsuko; Morimoto, Naoki; Hara, Tomoya; Ogawa, Takeshi; Mitsui, Toshihito; Kusumoto, Kenji

    2014-06-01

    Platelet-rich plasma (PRP) is blood plasma that has been enriched with platelets. It holds promise for clinical use in areas such as wound healing and regenerative medicine, including bone regeneration. This study characterized the composition of PRP produced by seven commercially available separation systems (JP200, GLO PRP, Magellan Autologous Platelet Separator System, KYOCERA Medical PRP Kit, SELPHYL, MyCells, and Dr. Shin's System THROMBO KIT) to evaluate the platelet, white blood cell, red blood cell, and growth factor concentrations, as well as platelet-derived growth factor-AB (PDGF-AB), transforming growth factor beta-1 (TGF-β1), and vascular endothelial growth factor (VEGF) concentrations. PRP prepared using the Magellan Autologous Platelet Separator System and the KYOCERA Medical PRP Kit contained the highest platelet concentrations. The mean PDGF-AB concentration of activated PRP was the highest from JP200, followed by the KYOCERA Medical PRP Kit, Magellan Autologous Platelet Separator System, MyCells, and GLO PRP. TGF-β1 and VEGF concentrations varied greatly among individual samples, and there was almost no significant difference among the different systems, unlike for PDGF. The SELPHYL system produced PRP with low concentrations of both platelets and growth factors. Commercial PRP separation systems vary widely, and familiarity with their individual advantages is important to extend their clinical application to a wide variety of conditions. PMID:24748436

  8. Biology of Blood

    Science.gov (United States)

    ... Mail Facebook TwitterTitle Google+ LinkedIn Home Blood Disorders Biology of Blood Overview of Blood Medical Dictionary Also ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  9. Circulating Endothelial Progenitor Cell and Platelet Microparticle Impact on Platelet Activation in Hypertension Associated with Hypercholesterolemia

    OpenAIRE

    Nicoleta Alexandru; Doina Popov; Emanuel Dragan; Eugen Andrei; Adriana Georgescu

    2013-01-01

    AIM: The purpose of this project was to evaluate the influence of circulating endothelial progenitor cells (EPCs) and platelet microparticles (PMPs) on blood platelet function in experimental hypertension associated with hypercholesterolemia. METHODS: Golden Syrian hamsters were divided in six groups: (i) control, C; (ii) hypertensive-hypercholesterolemic, HH; (iii) 'prevention', HHin-EPCs, HH animals fed a HH diet and treated with EPCs; (iv) 'regression', HHfin-EPCs, HH treated with EPCs aft...

  10. Analysis of aggregation of platelets in thrombosis

    Science.gov (United States)

    Ahuja, Suresh

    Platelets are key players in thrombus formation by first rolling over collagen bound von Willebrand factor followed by formation of a stable interaction with collagen. The first adhered platelets bind additional platelets until the whole injury is sealed off by a platelet aggregate. The coagulation system stabilizes the formed platelet plug by creating a tight fibrin network, and then wound contraction takes place because of morphological changes in platelets. Coagulation takes place by platelet activation and aggregation mainly through fibrinogen polymerization into fibrin fibers. The process includes multiple factors, such as thrombin, plasmin, and local shear-rate which regulate and control the process. Coagulation can be divided into two pathways: the intrinsic pathway and the extrinsic pathway. The intrinsic pathway is initiated by the exposure of a negatively charged. It is able to activate factor XII, using a complex reaction that includes prekallikrein and high-molecular-weight kininogen as cofactors.. Thrombin is the final enzyme that is needed to convert fibrinogen into fibrin. The extrinsic pathway starts with the exposure of tissue factor to the circulating blood, which is the major initiator of coagulation. There are several feedback loops that reinforce the coagulation cascade, resulting in large amounts of thrombin. It is dependent on the presence of pro-coagulant surfaces of cells expressing negatively charged phospholipids--which include phosphatidylserine (PS)--on their outer membrane. PS-bearing surfaces are able to increase the efficiency of the reactions by concentrating and co-localizing coagulation factors.. Aggregation of platelets are analyzed and compared to adhesion of platelet to erythrocyte and to endothelial cells. This abstract is replacing MAR16-2015-020003.

  11. ARTEMISIA DRACUNCULUS, PUNICA GRANATUM AND BERBERIS VULGARIS INHIBITORY EFFECTS ON PLATELET ADHESION AND COAGULATION FACTORS IN RATS

    Directory of Open Access Journals (Sweden)

    Dr. Razieh Yazdanparast et al

    2012-10-01

    Full Text Available Excessive platelet activity is one of the most important factors responsible for the incidence of cardiovascular diseases and, also, play important role in coagulation cascade. In this study, the comparative effects of methanol extracts of three herbs on adhesion of the activated platelets to fibrinogen coated plates and clotting factors were investigated. Artemisia dracunculus, Punica granatum and Brberis vulgaris are used as blood anti-coagulatory plants in Iranian folk medicine. Platelets were prepared and incubated with different concentration of the test samples (50-200 μg/ml for 60 min. The treated and un-treated platelets were then activated with thrombin (0.25U/ml and their adhesions to fibrinogen coated plates were investigated. Based on obtained data, the methanol extract of Artemisia dracunculus, Brberis vulgaris and Punica granatum at a concentration of 200 μg /ml reduced platelet adhesion to coated wells by 35%, 25% and 20%, respectively. In addition, the effects of the crude extracts of each plant on atherogenic lipoproteins were also examined. The results indicated that the LDL and cholesterol concentration were dramatically reduced by 56% and 36%, respectively, by B. vulgaris. This result provided the scientific basis for the traditional use of A.dracunculus and B. vulgaris in treatment of cardiovascular related disorders.

  12. Stiffening of Red Blood Cells Induced by Cytoskeleton Disorders: A Joint Theory-Experiment Study.

    Science.gov (United States)

    Lai, Lipeng; Xu, Xiaofeng; Lim, Chwee Teck; Cao, Jianshu

    2015-12-01

    The functions and elasticities of the cell are largely related to the structures of the cytoskeletons underlying the lipid bilayer. Among various cell types, the red blood cell (RBC) possesses a relatively simple cytoskeletal structure. Underneath the membrane, the RBC cytoskeleton takes the form of a two-dimensional triangular network, consisting of nodes of actins (and other proteins) and edges of spectrins. Recent experiments focusing on the malaria-infected RBCs (iRBCs) show that there is a correlation between the elongation of spectrins in the cytoskeletal network and the stiffening of the iRBCs. Here we rationalize the correlation between these two observations by combining the wormlike chain model for single spectrins and the effective medium theory for the network elasticity. We specifically focus on how the disorders in the cytoskeletal network affect its macroscopic elasticity. Analytical and numerical solutions from our model reveal that the stiffness of the membrane increases with increasing end-to-end distances of spectrins, but has a nonmonotonic dependence on the variance of the end-to-end distance distributions. These predictions are verified quantitatively by our atomic force microscopy and micropipette aspiration measurements of iRBCs. The model may, from a molecular level, provide guidelines for future identification of new treatment methods for RBC-related diseases, such as malaria infection. PMID:26636940

  13. Cognitive profiles and regional cerebral blood flow changes in individuals with Asperger's disorder and Schizophrenia

    International Nuclear Information System (INIS)

    Described are differences of the profiles and blood flow (CBF) changes in the title between individuals with Asperger's disorder (AD) and Schizophrenia (SZ). Children with AD syndrome have been suggested to have reasoning and fluid intelligence superior to normally developed ones, and to be of cognitive disability for the spatial composition which is thought to reflect the impairment in the right hemisphere. These characteristics are not suggested in SZ. Presented are examinations by authors of 99m ethyl cysteinate dimer (ECD)-single photon emission computed tomography (SPECT) images with Patlak method of 7 AD males (average age 24.4 y), 4 AD females (25.5 y), and 4 males and 2 females with SZ (25.8 y). Image analysis is done by SPM99 (Statistical Parametric Mapping) with standardized brain. Control with the matched age and sex is obtained from database of the normal healthy ones. In AD, clearly lowered CBF is observed in the right lateral and medial parietal lobe and right superior temporal convolution (particularly, in females), and in SZ, in the dorsolateral and dorsomedial regions of frontal lobe of both sides. The finding in the right superior temporal convolution in AD is considered to be important from the aspect of impairment of eye gaze processing. (R.T.)

  14. A General Aspect of Platelet Rich Plasma

    Directory of Open Access Journals (Sweden)

    Onur ORAL

    2015-08-01

    Full Text Available The aim of this scientific paper is to introduce Platelet Rich Plasma (PRP cure method by people who never heard about it. People can hurt their selves, thus they can have damaged tissue; for instance broken bone, a scar or a wounded area. Furthe rmore damaged tissue can be a cartilage tissue, which takes very long time to heal. Platelets, those exist in the veins as thrombus, come up to repair those damaged tissues. However, platelets would be insufficient to cure damaged area in a short time. At this point PRP cure method give a hand to the healing process. By centrifuging people’s own blood via special kits, platelets can be separated from blood cells as plasma. That plasma’s platelet density is 3 - 5 times greater than that blood’s platelet densit y. Afterwards PRP method is implemented by injection of plasma to the damaged area or tissue. After implementation of 2 - 4 sessions per week, damaged tissue can be regenerated. It is fast healing method because densified platelet plasma is used; and it is s afe because that plasma is obtained from people’s own blood. PRP can be implemented on many areas; for instance on dentistry, sports medicine, different kind of surgeries such as plastic, vascular or orthopedic and so on. When soccer players brake their le gs, their sports life come to the end, but what if their broken legs was healed better and faster than general healing process? To sum up, PRP is very safe and the future of healing process.

  15. Platelet function testing: methods of assessment and clinical utility.

    LENUS (Irish Health Repository)

    Mylotte, Darren

    2012-02-01

    Platelets play a central role in the regulation of both thrombosis and haemostasis yet tests of platelet function have, until recently, been exclusively used in the diagnosis and management of bleeding disorders. Recent advances have demonstrated the clinical utility of platelet function testing in patients with cardiovascular disease. The ex vivo measurement of response to antiplatelet therapies (aspirin and clopidogrel), by an ever-increasing array of platelet function tests, is with some assays, predictive of adverse clinical events and thus, represents an emerging area of interest for both the clinician and basic scientist. This review article will describe the advantages and disadvantages of the currently available methods of measuring platelet function and discuss both the limitations and emerging data supporting the role of platelet function studies in clinical practice.

  16. Platelet function testing: methods of assessment and clinical utility.

    LENUS (Irish Health Repository)

    Mylotte, Darren

    2011-01-01

    Platelets play a central role in the regulation of both thrombosis and haemostasis yet tests of platelet function have, until recently, been exclusively used in the diagnosis and management of bleeding disorders. Recent advances have demonstrated the clinical utility of platelet function testing in patients with cardiovascular disease. The ex vivo measurement of response to antiplatelet therapies (aspirin and clopidogrel), by an ever-increasing array of platelet function tests, is with some assays, predictive of adverse clinical events and thus, represents an emerging area of interest for both the clinician and basic scientist. This review article will describe the advantages and disadvantages of the currently available methods of measuring platelet function and discuss both the limitations and emerging data supporting the role of platelet function studies in clinical practice.

  17. ROLE OF PLATELET TRANSFUSIONS IN DENGUE HEMORRHAGIC FEVER- 6 MONTHS REPORT

    Directory of Open Access Journals (Sweden)

    Geeta

    2012-08-01

    Full Text Available ABSTRACT: BACKGROUND: Allogenic platelet transfusion plays a major role in the management of thrombocytopenia. The study includes details of pla telet transfusion over a period of 6 months from January-2011 to June-2011 at blood bank of Gan dhi Hospital. Total number of patients who received were 487 and proportionate use of total un its of RDP (Random Donor Platelets issued from blood bank were as follows; dengue hemorrhagic fever (38% and remaining for acute leukemia (12%, Aplastic anemia (10%, sepsis (10% , DIC (Disseminated Intravascular Coagulation (10%, cardiac surgery (10%. In dengu e hemorrhagic fever, correlation of platelet count with platelet transfusion and platelet increm ent have been evaluated.

  18. Modifications of platelet aggregation during treadmill section and obstacle course in athletic horse

    OpenAIRE

    Piccione G.; Assenza Anna; Casella Stefania; Giannetto Claudia; Tosto F.; Caola G.

    2010-01-01

    Eight clinically healthy Sella Italiana horses were used in order to assess the variations of platelet aggregation in response to different workload. Blood samples were collected from each horse at rest, immediately after exercise and 30 min after the end of the exercise. By means of an aggregometer platelet aggregation was quantitated as maximum degree of platelet aggregation and initial velocity platelet aggregation. Two-way repeated measures analysis of variance (ANOVA) was applied to dete...

  19. Antipsychotic Drugs Inhibit Platelet Aggregation via P2Y 1 and P2Y 12 Receptors

    OpenAIRE

    Chang-Chieh Wu; Fu-Ming Tsai; Mao-Liang Chen; Semon Wu; Ming-Cheng Lee; Tzung-Chieh Tsai; Lu-Kai Wang; Chun-Hua Wang

    2016-01-01

    Antipsychotic drugs (APDs) used to treat clinical psychotic syndromes cause a variety of blood dyscrasias. APDs suppress the aggregation of platelets; however, the underlying mechanism remains unknown. We first analyzed platelet aggregation and clot formation in platelets treated with APDs, risperidone, clozapine, or haloperidol, using an aggregometer and rotational thromboelastometry (ROTEM). Our data indicated that platelet aggregation was inhibited, that clot formation time was increased, ...

  20. Presence of intratumoral platelets is associated with tumor vessel structure and metastasis

    OpenAIRE

    Li, Rong; Ren, Meiping; Chen, Ni; Luo, Mao; Deng, Xin; Xia, Jiyi; Yu, Guang; Liu, Jinbo; HE Bing; Zhang, Xu; Zhang, Zhuo; Zhang, Xiao; Ran, Bing; Wu, Jianbo

    2014-01-01

    Background Platelets play a fundamental role in maintaining hemostasis and have been shown to participate in hematogenous dissemination of tumor cells. Abundant platelets were detected in the tumor microenvironment outside of the blood vessel, thus, platelet -tumor cell interaction outside of the bloodstream may play a role in regulating primary tumor growth and metastasis initiation. However, it is unclear that platelet depletion affects tumor vessel structure and dynamics. Methods Using thr...

  1. Platelet Activation Determines Angiopoietin-1 and VEGF Levels in Malaria: Implications for Their Use as Biomarkers

    OpenAIRE

    Judith Brouwers; Rintis Noviyanti; Rob Fijnheer; de Groot, Philip G.; Leily Trianty; Siti Mudaliana; Mark Roest; Din Syafruddin; Andre van der Ven; Quirijn de Mast

    2013-01-01

    INTRODUCTION: The angiogenic proteins angiopoietin (Ang)-1, Ang-2 and vascular endothelial growth factor (VEGF) are regulators of endothelial inflammation and integrity. Since platelets store large amounts of Ang-1 and VEGF, measurement of circulation levels of these proteins is sensitive to platelet number, in vivo platelet activation and inadvertent platelet activation during blood processing. We studied plasma Ang-1, Ang-2 and VEGF levels in malaria patients, taking the necessary precautio...

  2. Platelet serotonin transporter function predicts default-mode network activity.

    Directory of Open Access Journals (Sweden)

    Christian Scharinger

    Full Text Available The serotonin transporter (5-HTT is abundantly expressed in humans by the serotonin transporter gene SLC6A4 and removes serotonin (5-HT from extracellular space. A blood-brain relationship between platelet and synaptosomal 5-HT reuptake has been suggested, but it is unknown today, if platelet 5-HT uptake can predict neural activation of human brain networks that are known to be under serotonergic influence.A functional magnetic resonance study was performed in 48 healthy subjects and maximal 5-HT uptake velocity (Vmax was assessed in blood platelets. We used a mixed-effects multilevel analysis technique (MEMA to test for linear relationships between whole-brain, blood-oxygen-level dependent (BOLD activity and platelet Vmax.The present study demonstrates that increases in platelet Vmax significantly predict default-mode network (DMN suppression in healthy subjects independent of genetic variation within SLC6A4. Furthermore, functional connectivity analyses indicate that platelet Vmax is related to global DMN activation and not intrinsic DMN connectivity.This study provides evidence that platelet Vmax predicts global DMN activation changes in healthy subjects. Given previous reports on platelet-synaptosomal Vmax coupling, results further suggest an important role of neuronal 5-HT reuptake in DMN regulation.

  3. Low platelet monoamine oxidase activity in pathological gambling

    International Nuclear Information System (INIS)

    Decreased platelet monoamine oxidase (MAO) activity has been reported in association with sensation-seeking personality type and in some mental disorders associated with a lack of impulse control. Pathological gambling itself has been related with both sensation-seeking and reduced impulse control. Platelet MAO activity was investigated in 15 DSM-III-R pathological gamblers from our outpatient clinic. Gamblers had a significantly lower platelet MAO activity than a group of 25 healthy controls. The range of MAO levels in gamblers was also significantly shorter than in controls. In controls, platelet MAO levels showed the previously described negative correlations with sensation-seeking scores but not in gamblers. The findings are consistent with previous studies showing an association of low platelet MAO activity with impulse control disorders and raise some interesting therapeutic alternatives for pathological gambling. (au) (40 refs.)

  4. Adenosine-mediated inhibition of platelet aggregation by acadesine. A novel antithrombotic mechanism in vitro and in vivo.

    OpenAIRE

    Bullough, D A; Zhang, C.; Montag, A; Mullane, K. M.; Young, M A

    1994-01-01

    Inhibition of platelet aggregation by acadesine was evaluated both in vitro and ex vivo in human whole blood using impedance aggregometry, as well as in vivo in a canine model of platelet-dependent cyclic coronary flow reductions. In vitro, incubation of acadesine in whole blood inhibited ADP-induced platelet aggregation by 50% at 240 +/- 60 microM. Inhibition of platelet aggregation was time dependent and was prevented by the adenosine kinase inhibitor, 5'-deoxy 5-iodotubercidin, which block...

  5. Treatment of osteochondral injuries with platelet gel

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Danieli

    2014-12-01

    Full Text Available OBJECTIVES: Treatments for injured articular cartilage have not advanced to the point that efficient regeneration is possible. However, there has been an increase in the use of platelet-rich plasma for the treatment of several orthopedic disorders, including chondral injuries. Our hypothesis is that the treatment of chondral injuries with platelet gel results in higher-quality repair tissue after 180 days compared with chondral injuries not treated with gel. METHODS: A controlled experimental laboratory study was performed on 30 male rabbits to evaluate osteochondral injury repair after treatment with or without platelet gel. Osteochondral injuries were surgically induced in both knees of each rabbit at the medial femoral condyle. The left knee injury was filled with the platelet gel, and the right knee was not treated. Microscopic analysis of both knee samples was performed after 180 days using a histological grading scale. RESULTS: The only histological evaluation criterion that was not significantly different between treatments was metachromasia. The group that was treated with platelet gel exhibited superior results in all other criteria (cell morphology, surface regularity, chondral thickness and repair tissue integration and in the total score. CONCLUSION: The repair tissue was histologically superior after 180 days in the study group treated with platelet gel compared with the group of untreated injuries.

  6. Effects of clomipramine treatment on cerebrospinal fluid monoamine metabolites and platelet 3H-imipramine binding and serotonin uptake and concentration in major depressive disorder

    International Nuclear Information System (INIS)

    In an open study of 12 inpatients who met the DSM-III criteria for a major depressive episode, the effects of clomipramine (CI) on the monoamine metabolites 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), 4-hydroxy-3-methoxyphenyl glycol (HMPG) in cerebrospinal fluid (CSF) were measured simultaneously with the effects on 3H-imipramine binding, serotonin (5-HT) uptake and 5-HT concentration in platelets after 3 and 6 weeks of treatment. Drug (CI and desmethylclomipramine) plasma concentrations were determined. The concentrations of 5-HIAA and HMPG decreased substantially, and the concentration of HVA remained unchanged. There was also a large and significant reduction of the number of imipramine binding sites (Bmax) and of the platelet 5-HT concentration. The 5-HT uptake was not measurable aftet 3 weeks of treatment. None of the parameters changed significantly between weeks 3 and 6. There were no significant correlations between antidepressant effect (measured by the Montgomery-Aasberg Depression Rating Scale) and plasma drug concentrations, although a tendency to a significant correlation between antidepressant effect and CI was observed at 3 weeks. There were no significant intercorrelations between the different 5-HT parameters and no other significant correlations between the biochemical measures and clinical outcome. (author)

  7. Metabolomics as a Tool for Discovery of Biomarkers of Autism Spectrum Disorder in the Blood Plasma of Children

    OpenAIRE

    West, Paul R.; Amaral, David G.; Bais, Preeti; Smith, Alan M.; Egnash, Laura A.; Ross, Mark E.; Palmer, Jessica A.; Fontaine, Burr R.; Conard, Kevin R.; Corbett, Blythe A.; Cezar, Gabriela G.; Donley, Elizabeth L. R.; Burrier, Robert E.

    2014-01-01

    Background The diagnosis of autism spectrum disorder (ASD) at the earliest age possible is important for initiating optimally effective intervention. In the United States the average age of diagnosis is 4 years. Identifying metabolic biomarker signatures of ASD from blood samples offers an opportunity for development of diagnostic tests for detection of ASD at an early age. Objectives To discover metabolic features present in plasma samples that can discriminate children with ASD from typical...

  8. Path to facilitate the prediction of functional amino acid substitutions in red blood cell disorders--a computational approach.

    Directory of Open Access Journals (Sweden)

    Rajith B

    Full Text Available BACKGROUND: A major area of effort in current genomics is to distinguish mutations that are functionally neutral from those that contribute to disease. Single Nucleotide Polymorphisms (SNPs are amino acid substitutions that currently account for approximately half of the known gene lesions responsible for human inherited diseases. As a result, the prediction of non-synonymous SNPs (nsSNPs that affect protein functions and relate to disease is an important task. PRINCIPAL FINDINGS: In this study, we performed a comprehensive analysis of deleterious SNPs at both functional and structural level in the respective genes associated with red blood cell metabolism disorders using bioinformatics tools. We analyzed the variants in Glucose-6-phosphate dehydrogenase (G6PD and isoforms of Pyruvate Kinase (PKLR & PKM2 genes responsible for major red blood cell disorders. Deleterious nsSNPs were categorized based on empirical rule and support vector machine based methods to predict the impact on protein functions. Furthermore, we modeled mutant proteins and compared them with the native protein for evaluation of protein structure stability. SIGNIFICANCE: We argue here that bioinformatics tools can play an important role in addressing the complexity of the underlying genetic basis of Red Blood Cell disorders. Based on our investigation, we report here the potential candidate SNPs, for future studies in human Red Blood Cell disorders. Current study also demonstrates the presence of other deleterious mutations and also endorses with in vivo experimental studies. Our approach will present the application of computational tools in understanding functional variation from the perspective of structure, expression, evolution and phenotype.

  9. Team-based learning on a third-year pediatric clerkship improves NBME subject exam blood disorder scores

    OpenAIRE

    Saudek, Kris; Treat, Robert

    2015-01-01

    Purpose: At our institution, speculation amongst medical students and faculty exists as to whether team-based learning (TBL) can improve scores on high-stakes examinations over traditional didactic lectures. Faculty with experience using TBL developed and piloted a required TBL blood disorders (BD) module for third-year medical students on their pediatric clerkship. The purpose of this study is to analyze the BD scores from the NBME subject exams before and after the introduction of the modul...

  10. Disorders of sex development expose transcriptional autonomy of genetic sex and androgen-programmed hormonal sex in human blood leukocytes

    OpenAIRE

    Appari Mahesh; Cario Gunnar; Richter-Unruh Annette; Demeter Janos; Werner Ralf; Bebermeier Jan-Hendrik; Holterhus Paul-Martin; Siebert Reiner; Riepe Felix; Brooks James D; Hiort Olaf

    2009-01-01

    Abstract Background Gender appears to be determined by independent programs controlled by the sex-chromosomes and by androgen-dependent programming during embryonic development. To enable experimental dissection of these components in the human, we performed genome-wide profiling of the transcriptomes of peripheral blood mononuclear cells (PBMC) in patients with rare defined "disorders of sex development" (DSD, e.g., 46, XY-females due to defective androgen biosynthesis) compared to normal 46...

  11. Suspension properties of whole blood and its components under glucose influence studied in patients with acute coronary syndrome

    Science.gov (United States)

    Malinova, Lidia I.; Simonenko, Georgy V.; Denisova, Tatyana P.; Dovgalevsky, Pavel Y.; Tuchin, Valery V.

    2004-05-01

    The protocol of our study includes men with acute myocardial infarction, stable angina pectoris of II and III functional classes and unstable angina pectoris. Patients with arterial hypertension, disorders in carbohydrate metabolism were excluded from the study. Blood samples taken under standardized conditions, were stabilized with citrate sodium 3,8% (1:9). Erythrocytes and platelets aggregation activity under glucose influence (in vitro) was studied by means of computer aided microphotometer -- a visual analyzer. Erythrocyte and platelets were united in special subsystem of whole blood. Temporal and functional characteristics of their aggregation were analyzed by creation of phase patterns fragments. The received data testify to interrelation of erythrocytes and platelets processes of aggregation under conditions of increasing of glucose concentration of the incubatory environment, which temporal and functional characteristics may be used for diagnostics and the prognosis of destabilization coronary blood flow at an acute coronary syndrome.

  12. Old diseases and contemporary crisis. Inherited blood disorders in the Sultanate of Oman.

    Science.gov (United States)

    Beaudevin, Claire

    2013-01-01

    This contribution draws on ethnographic research conducted in Oman on inherited blood disorders (IBD). By interpreting results from population genomics studies that trace mutation processes over centuries of human activities, lay-representations of IBD often consider them historical evidence. The perceived spread of IBD in Oman may thus provide unusual historical depth in a country where past conflicts have been erased from historiography and representations of time are politically prescribed. Through the notions of crisis and diversification, this contribution shows how IBD's chronicity challenges the healthcare system and became a national issue, politically labelled as urgent. The paper casts light on several aspects of contemporary Omani society: it first addresses the dynamics of disease taxonomies - although biomedically described in the early twentieth century, IBD were not individualized within local nosologies until the 1970s. Secondly, it shows how biomedical knowledge about IBD led to diversification within the healthcare system, through the introduction of clinical genetics, genomics, and community genetics. Thirdly, it attempts to broach modalities of the biopower exerted by the Omani regime over its citizens: IBD are targeted by various public health measures that jeopardize patients' autonomy by aiming to control their bodies through their matrimonial behaviour. In addition, two aspects of the intersections between Omani social hierarchy and IBD are noteworthy: the creation of a patients' association that constitutes a potential disturbance of the social order; and the way IBD mutations traced by genomics are considered direct historical documents that challenge representations of the recently crafted 'Omanity' in a context of regional concern regarding national identities' durability. PMID:23898837

  13. Whole blood BDNF levels in healthy twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Trajkovska, Viktorija; Vinberg, Maj; Aznar, Susana;

    2008-01-01

    BACKGROUND: Depression has been associated with decreased blood BDNF concentrations; but it is unclear if low blood BDNF levels are a state or a trait marker of depression. METHODS: We investigated blood BDNF concentrations in a twin population including both subjects highly predisposed and prote...

  14. Regional cerebral blood flow in mood disorders. I. Comparison of major depressives and normal controls at rest

    International Nuclear Information System (INIS)

    We measured regional cerebral blood flow with the xenon 133 inhalation technique in 41 patients with major depressive disorder and 40 matched, normal controls during an eyes-closed, resting condition. The depressed group had a marked reduction in global cortical blood flow. To examine topographic abnormalities, traditional multivariate analyses were applied, as well as a new scaled subprofile model developed to identify abnormal functional neural networks in clinical samples. Both approaches indicated that the depressed sample had an abnormality in topographic distribution of blood flow, in addition to the global deficit. The scaled subprofile model identified the topographic abnormality as being due to flow reduction in the depressed patients in selective frontal, central, superior temporal, and anterior parietal regions. This pattern may reflect dysfunction in the parallel distributed cortical network involving frontal and temporoparietal polymodal association areas. The extent of this topographic abnormality, as revealed by the scaled subprofile model, was associated with both patient age and severity of depressive symptoms

  15. Platelets enhance neutrophil transendothelial migration

    Science.gov (United States)

    Platelets are increasingly recognized as important mediators of inflammation in addition to thrombosis. While platelets have been shown to promote neutrophil (PMN) adhesion to endothelium in various inflammatory models, it is unclear whether platelets enhance neutrophil transmigration across inflame...

  16. Cytofluorometric identification of plasmin-sensitive factor XIIIa binding to platelets.

    Science.gov (United States)

    Kreager, J A; Devine, D V; Greenberg, C S

    1988-08-30

    We have investigated the binding of blood coagulation factor XIIIa to thrombin-stimulated platelets using cytofluorometric analysis. Washed thrombin-stimulated platelets bound exogenously added factor XIIIa in a calcium-dependent reaction. The expression of endogenous platelet factor XIII was also detected on the surface of thrombin-stimulated platelets. When fluorescence analysis was performed based on particle size, factor XIIIa bound to the surface of greater than 95% of particles which contained more than one platelet, but only 50% of single platelets. The binding of factor XIIIa to thrombin-stimulated platelets was inhibited by plasmin. Plasmin also inhibited thrombin-dependent expression of the factor XIIIa binding site on platelets. Experiments in which thrombin-stimulated platelets were incubated with factor XIIIa in the presence of 125I-dimethylcasein or 3H-putrescine demonstrated that platelets bear both glutamyl and lysyl substrates for factor XIIIa. Thrombin increased the expression of factor XIIIa substrates by platelets. Plasmin inhibited both the expression of factor XIIIa substrates and degraded them. The binding of factor XIIIa to thrombin-stimulated platelets and the availability of factor XIIIa substrates on the platelet surface could provide a mechanism by which factor XIIIa stabilizes the hemostatic plug by promoting crosslinking reactions between platelet membrane proteins and adhesive glycoproteins. In contrast, plasmin inhibition of factor XIIIa binding and crosslinking could disrupt hemostasis. PMID:2903577

  17. In vitro platelet activation, aggregation and platelet-granulocyte complex formation induced by surface modified single-walled carbon nanotubes.

    Science.gov (United States)

    Fent, János; Bihari, Péter; Vippola, Minnamari; Sarlin, Essi; Lakatos, Susan

    2015-08-01

    Surface modification of single-walled carbon nanotubes (SWCNTs) such as carboxylation, amidation, hydroxylation and pegylation is used to reduce the nanotube toxicity and render them more suitable for biomedical applications than their pristine counterparts. Toxicity can be manifested in platelet activation as it has been shown for SWCNTs. However, the effect of various surface modifications on the platelet activating potential of SWCNTs has not been tested yet. In vitro platelet activation (CD62P) as well as the platelet-granulocyte complex formation (CD15/CD41 double positivity) in human whole blood were measured by flow cytometry in the presence of 0.1mg/ml of pristine or various surface modified SWCNTs. The effect of various SWCNTs was tested by whole blood impedance aggregometry, too. All tested SWCNTs but the hydroxylated ones activate platelets and promote platelet-granulocyte complex formation in vitro. Carboxylated, pegylated and pristine SWCNTs induce whole blood aggregation as well. Although pegylation is preferred from biomedical point of view, among the samples tested by us pegylated SWCNTs induced far the most prominent activation and a well detectable aggregation of platelets in whole blood. PMID:25956790

  18. Inhalation of nitric oxide inhibits ADP-induced platelet aggregation and alpha-granule release.

    Science.gov (United States)

    Hagberg, I A; Sølvik, U Ø; Opdahl, H; Roald, H E; Lyberg, T

    1999-01-01

    To gather further information about the effects on blood platelet activation of in vivo exposure to nitric oxide (NO), platelet reactivity was studied in blood from healthy, non-smoking male volunteers before and after 30 min inhalation of 40 ppm NO. Whole blood was stimulated in vitro with adenosine diphosphate or thrombin receptor activation peptide (TRAP-6). In an ex vivo perfusion model, non-anticoagulated blood was exposed to immobilised collagen at arterial blood flow conditions (2600 s(-1)). Blood samples from both the in vitro and ex vivo experiments were stained with fluorochrome-labelled Annexin-V and antibodies against CD42a, CD45, CD49b, CD61, CD62P and fibrinogen, and analysed with a three-colour flow cytometry technique. NO inhalation reduced the platelet activation response to adenosine diphosphate (ADP) stimulation by decreasing platelet-platelet aggregation, alpha-granule release and platelet-leukocyte conjugate formation. TRAP-stimulated platelet activation, collagen-induced platelet activation and thrombus growth was unaffected by NO inhalation. We therefore suggest an ADP receptor inhibitor mode of action of inhaled NO, selective on the newly suggested G protein- and phospholipase C-coupled P2Y1 receptor. Our results demonstrate that blood platelet activation in healthy subjects is modulated by inhalation of NO in therapeutically relevant doses, although the clinical impact of our findings remains unclear. PMID:16801117

  19. Continuation of medically necessary platelet aggregation inhibitors - acetylsalicylic acid and clopidogrel - during surgery for spinal degenerative disorders: Results in 100 patients

    Directory of Open Access Journals (Sweden)

    Reza Akhavan-Sigari

    2014-01-01

    Full Text Available Background: Patients undergoing spinal surgery while under anticoagulation therapy are at risk of developing bleeding complications, even though lower incidences have been reported for joint arthroplasty surgery. There is a gap in the medical literature examining the incidence of postoperative spinal bleeding in patients who were under anticoagulation medication at the time of surgery. Methods: We prospectively followed a consecutive cohort of 100 patients (58 male, 42 female undergoing spinal surgery. The average patient age was 48.7 years and the minimum follow up time was 12 months. Diagnosis was lumbar spinal stenosis in 20, herniated lumbar discs in 63, degenerative cervical disc disease in 3, and cervical disc herniation in 14 cases. In our study, platelet aggregation inhibitors (clopidogrel and/or acetylsalicylic acid were given for the treatment of cardiovascular and cerebrovascular thrombotic events, to reduce risk of stroke in patients who have had transient ischemia of the brain or acute coronary syndrome, and as secondary prevention of atherosclerotic events (fatal or nonfatal myocardial infarction (MI. A cessation of anticoagulants (acetylsalicylic acid or clopidogrel in our patients in the peri- and postoperative period was contraindicated. Results: Sixty-three patients were on both clopidogrel and acetylsalicylic acid and 37 on acetylsalicylic acid only. None of the patients suffered any postoperative bleeding complication. Three patients suffered postoperative wound dehiscence and one patient had an infection that required reoperation. Conclusion: The question of whether preoperative platelet aggregation inhibitors must be stopped before elective spinal surgery has never been answered in the literature. In our prospective series, we have found no increase in the risk of postoperative spinal bleeding with the use of clopidogrel or acetylsalicylic acid. This finding suggests that spine surgery can be done without stopping

  20. Study of Platelet Serotonin in Adolescents with Internet Addiction Disorder%青少年网络成瘾患者血小板5-羟色胺水平分析

    Institute of Scientific and Technical Information of China (English)

    罗江洪; 吴汉荣; 蒙衡; 杜亚松; 林治光

    2011-01-01

    Objective To explore the role of serotonin ( 5 - HT) in internet addiction disorder ( IAD), and to provide evidence for the behavioral intervention and medical treatment. Methods Thirty-three adolescents with lAD and 44 normal ones as control were included in the study.Platelet serotonin level was determined with high performance liquid chromatography. Emotional status was investigated with Self-rating Depression Scale ( SDS) and Self-rating Anxiety Scale (SAS). A t-test and correlation analysis were used by SPSS 14. 0. Results Platelet serotonin level of lAD was significantly lower than that of controls ( t = - 2. 135 ,P < 0.05 ). SDS and SAS scores of lAD group were significantly higher than that of control group ( P < 0. 05 ). Correlation analysis showed platelet serotonin level was related with the degree of lAD, SDS and SAS ( P < 0.05 ). Conclusion IAD is perhaps related to neurons' maladjustment.%目的 探索5-羟色胺(5-HT)在青少年网络成瘾发生中的作用,为心理疏导、行为干预和药物治疗提供依据.方法 应用高效液相色谱法,测定33例网络成瘾患者青少年和44例正常对照的血小板5-HT含量;采用抑郁自评量表(SDS)、焦虑自评量表(SAS),测评情绪状态.应用SPSS 14.0进行t检验和相关分析.结果 网络成瘾组血小板5-HT水平低于正常对照组,差异有统计学意义(t=-2.135,P<0.05);网络成瘾组抑郁评分高于对照组,差异有统计学意义(t=3.310,P<0.01);网络成瘾组焦虑评分高于对照组,差异有统计学意义(t=3.110,P<0.01).相关分析显示,血小板5-HT水平与网络成瘾、抑郁、焦虑程度均呈负相关(P值均<0.05).结论 网络成瘾发病可能与神经元功能失调有关.

  1. Blood Clotting and Pregnancy

    Medline Plus

    Full Text Available ... For Patients Blood Disorders Blood Clots Blood Clotting & Pregnancy If you are pregnant, or you have just ... The risk of developing a blood clot during pregnancy is increased by the following: Previous blood clots ...

  2. The effects of ropivacaine hydrochloride on platelet function: an assessment using the platelet function analyser (PFA-100).

    LENUS (Irish Health Repository)

    Porter, J

    2012-02-03

    Amide local anaesthetics impair blood clotting in a concentration-dependent manner by inhibition of platelet function and enhanced fibrinolysis. We hypothesised that the presence of ropivacaine in the epidural space could decrease the efficacy of an epidural blood patch, as this technique requires that the injected blood can clot in order to be effective. Ropivacaine is an aminoamide local anaesthetic used increasingly for epidural analgesia during labour. The concentration of local anaesthetic in blood achieved in the epidural space during the performance of an epidural blood patch is likely to be the greatest which occurs (intentionally) in any clinical setting. This study was undertaken to investigate whether concentrations of ropivacaine in blood, which could occur: (i) clinically in the epidural space and (ii) in plasma during an epidural infusion of ropivacaine, alter platelet function. A platelet function analyser (Dade PFA-100, Miami) was employed to assess the effects of ropivacaine-treated blood on platelet function. The greater concentrations of ropivacaine studied (3.75 and 1.88 mg x ml(-1)), which correspond to those which could occur in the epidural space, produced significant inhibition of platelet aggregation. We conclude that the presence of ropivacaine in the epidural space may decrease the efficacy of an early or prophylactic epidural blood patch.

  3. Are Platelets Cells? And if Yes, Are They Immune Cells?

    Directory of Open Access Journals (Sweden)

    Fabrice eCOGNASSE

    2015-02-01

    Full Text Available Small fragments circulating in the blood were formally identified by the end of the 19th century, and it was suggested that they assisted coagulation via interactions with vessel endothelia. Wright, at the beginning of the 20th century, identified their bone-marrow origin. For long, platelets have been considered sticky assistants of hemostasis and pollutants of blood or tissue samples; they were just cell fragments. As such however, they were acknowledged as immunizing (to specific HPA and HLA markers: the platelet’s dark face. The enlightened face showed that besides hemostasis, platelets contained factors involved in healing. As early as the 1930s, platelets entered the arsenal of medicines; were transfused, and were soon manipulated to become a kind of glue to repair damaged tissues. Some gladly categorized platelets as cells but they were certainly not fully licensed as such for cell physiologists. Actually, platelets possess almost every characteristic of cells, apart from being capable of organizing their genes: they have neither a nucleus nor genes. This view prevailed until it became evident that platelets play a role in homeostasis and interact with cells other than with vascular endothelial cells; then began the era of physiological and also pathological inflammation. Platelets have now entered the field of immunity as inflammatory cells. Does assistance to immune cells itself suffice to license a cell as an immune cell? Platelets prove capable of sensing different types of signals and organizing an appropriate response. Many cells can do that. However, platelets can use a complete signalosome (apart from the last transcription step, though it is likely that this step can be circumvented by retrotranscribing RNA messages. The question has also arisen as to whether platelets can present antigen via their abundantly expressed MHC class I molecules. In combination, these properties argue in favor of allowing platelets the title of

  4. Use of Platelet Gel and Its Effects on Infection in Cardiac Surgery

    OpenAIRE

    Trowbridge, Cody C.; Stammers, Alfred H.; Woods, Edward; Yen, Bianca R.; Klayman, Myra; Gilbert, Christian

    2005-01-01

    The use of plasmapheresis in cardiac surgery has failed to show an unequivocal benefit. However, the further processing of plasmapheresed blood to obtain a platelet-rich concentrate, termed platelet gel, may reduce patient susceptibility to infection through poorly understood mechanisms related to a combination of platelets, white blood cell content, and expedited wound healing. The purpose of the study was to retrospectively evaluate the incidence wound infections in patients undergoing card...

  5. Inhibitory Effects of Yuzu and Its Components on Human Platelet Aggregation

    OpenAIRE

    Kim, Tae-Ho; Kim, Hye-Min; Park, Se Won; Jung, Yi-Sook

    2015-01-01

    Our previous study demonstrated that yuzu has an anti-platelet effect in rat blood. In the present study, we examined whether the anti-platelet effect of yuzu can be extended to human blood by investigating its ability to inhibit aggregations induced by various agonists in human platelet rich plasma (PRP). This study also investigated the underlying mechanism of yuzu focusing on ADP granule secretion, TXB2 formations, and PLCγ/Akt signaling. The results from this study showed that ethanolic y...

  6. A novel platelet concentrate: titanium-prepared platelet-rich fibrin.

    Science.gov (United States)

    Tunalı, Mustafa; Özdemir, Hakan; Küçükodacı, Zafer; Akman, Serhan; Yaprak, Emre; Toker, Hülya; Fıratlı, Erhan

    2014-01-01

    We developed a new product called titanium-prepared platelet-rich fibrin (T-PRF). The T-PRF method is based on the hypothesis that titanium may be more effective in activating platelets than the silica activators used with glass tubes in Chouckroun's leukocyte- and platelet-rich fibrin (L-PRF) method. In this study, we aimed to define the structural characteristics of T-PRF and compare it with L-PRF. Blood samples were collected from 10 healthy male volunteers. The blood samples were drawn using a syringe. Nine milliliters was transferred to a dry glass tube, and 9 mL was transferred to a titanium tube. Half of each clot (i.e., the blood that was clotted using T-PRF or L-PRF) was processed with a scanning electron microscope (SEM). The other half of each clot was processed for fluorescence microscopy analysis and light microscopy analysis. The T-PRF samples seemed to have a highly organized network with continuous integrity compared to the other L-PRF samples. Histomorphometric analysis showed that T-PRF fibrin network covers larger area than L-PRF fibrin network; also fibrin seemed thicker in the T-PRF samples. This is the first human study to define T-PRF as an autogenous leukocyte- and platelet-rich fibrin product. The platelet activation by titanium seems to offer some high characteristics to T-PRF. PMID:24563860

  7. Platelet Function Tests

    Science.gov (United States)

    ... of the clotting process in the body ( in vivo ). A person with normal platelet function test results may still experience excessive bleeding or inappropriate clotting during and after a surgery. Most samples for platelet function testing are only stable for a very short period ...

  8. Mean platelet volume measurement, EDTA or citrate?

    Science.gov (United States)

    Dastjerdi, Mansour Siavash; Emami, Tajolmolouk; Najafian, Alireza; Amini, Masoud

    2006-10-01

    Most laboratories use EDTA for anticoagulation of whole blood prior to automated cell counting but due to platelet swelling, mean platelet volume (MPV) values may increase with its use. MPV changes may be less with acid citrate based anticoagulation. As MPV is a marker of platelet function and its precise measurement is important in a number of clinical situations, this study was performed to assess if EDTA and citrate based anticoagulated blood samples can be used interchangeably for MPV measurement. In this cross sectional descriptive study, EDTA and citrate based anticoagulated blood samples of the same patients were assessed by auto-analyzer within 1 h of sampling. In the 61 evaluated patients, there was a close correlation between MPV as measured by EDTA and citrate, but mean MPV measured from EDTA samples was 0.66 fL (9%) more than citrate. There was also a significant negative correlation between platelets count and MPV by both methods. The results of our study reveal that MPV can be measured accurately by both methods of anticoagulation; EDTA and citrate if analysis be performed within 1 h of sampling. PMID:17607580

  9. In vitro model of platelet aggregation in stenotic arteries

    International Nuclear Information System (INIS)

    Clinical and experimental evidence suggest a strong relationship between arterial stenosis, platelet aggregation, and subsequent thrombus formation. To facilitate the study of platelet accumulation in stenotic arteries, we developed an in vitro preparation. Arterial segments were perfused with whole citrated blood. A stenosis was created by applying an external plastic constrictor to the artery. Platelet accumulation within the stenosis was assessed by scanning electron microscopy and by radioactive counts from Indium-111 labeled platelets. Utilizing this preparation, 30 carotid arterial segments from 10 mongrel dogs were perfused at 100 mmHg for 15 min. In 10 arteries without a stenosis, scanning electron microscopy and radioactive counts demonstrated little platelet accumulation. In contrast, extensive platelet aggregation was observed in 10 arteries with stenoses. Moreover, in 10 stenotic arteries exposed to the thromboxane mimetic, U46619 (Upjohn Diagnostic Group), scanning electron microscopy and radioactive counts demonstrated a significant increase in platelet deposition. Conversely, we demonstrated a dimunition of platelet accumulation in stenosed arterial segments exposed to the prostacyclin analogue platelet inhibitor, Iloprost. The in vitro preparation allows precise control of hemodynamic variables and makes it possible to perform multiple tests on segments of the same vessel from the same animal

  10. Platelet Donation (Apheresis)

    Science.gov (United States)

    ... Donation Student Donors Donation Process Eligibility Blood FAQs Blood Donor Community Learn About Blood Blood Facts and Statistics Blood Types Blood Components What Happens to Donated Blood Blood and Diversity History of Blood Transfusion Hosting a Blood Drive What to Expect Hosting ...

  11. Treatment of Anxiety Disorders and Comorbid Alcohol Abuse with Buspirone in a Patient with Antidepressant-Induced Platelet Dysfunction: A Case Report

    OpenAIRE

    Mir Mazhar; Tariq Hassan; Tariq Munshi

    2013-01-01

    The risk of abnormal bleeding with serotonin reuptake inhibitors has been known, but there is insufficient evidence base to guide pharmacological treatment of anxiety in patients with underlying haematological conditions. The following case report is about a 50-year-old female with generalized anxiety disorder, social phobia, obsessive compulsive disorder, and alcohol abuse where pharmacological treatment of anxiety symptoms has been difficult as it would lead to bruising due to the patient’s...

  12. The Expression of Caspases Is Enhanced in Peripheral Blood Mononuclear Cells of Autism Spectrum Disorder Patients

    Science.gov (United States)

    Siniscalco, Dario; Sapone, Anna; Giordano, Catia; Cirillo, Alessandra; de Novellis, Vito; de Magistris, Laura; Rossi, Francesco; Fasano, Alessio; Maione, Sabatino; Antonucci, Nicola

    2012-01-01

    Autism and autism spectrum disorders (ASDs) are heterogeneous complex neuro-developmental disorders characterized by dysfunctions in social interaction and communication skills. Their pathogenesis has been linked to interactions between genes and environmental factors. Consistent with the evidence of certain similarities between immune cells and…

  13. Transport characteristics of guanidino compounds at the blood-brain barrier and blood-cerebrospinal fluid barrier: relevance to neural disorders

    Directory of Open Access Journals (Sweden)

    Tachikawa Masanori

    2011-02-01

    Full Text Available Abstract Guanidino compounds (GCs, such as creatine, phosphocreatine, guanidinoacetic acid, creatinine, methylguanidine, guanidinosuccinic acid, γ-guanidinobutyric acid, β-guanidinopropionic acid, guanidinoethane sulfonic acid and α-guanidinoglutaric acid, are present in the mammalian brain. Although creatine and phosphocreatine play important roles in energy homeostasis in the brain, accumulation of GCs may induce epileptic discharges and convulsions. This review focuses on how physiologically important and/or neurotoxic GCs are distributed in the brain under physiological and pathological conditions. Transporters for GCs at the blood-brain barrier (BBB and the blood-cerebrospinal fluid (CSF barrier (BCSFB have emerged as substantial contributors to GCs distribution in the brain. Creatine transporter (CRT/solute carrier (SLC 6A8 expressed at the BBB regulates creatine concentration in the brain, and represents a major pathway for supply of creatine from the circulating blood to the brain. CRT may be a key factor facilitating blood-to-brain guanidinoacetate transport in patients deficient in S-adenosylmethionine:guanidinoacetate N-methyltransferase, the creatine biosynthetic enzyme, resulting in cerebral accumulation of guanidinoacetate. CRT, taurine transporter (TauT/SLC6A6 and organic cation transporter (OCT3/SLC22A3 expressed at the BCSFB are involved in guanidinoacetic acid or creatinine efflux transport from CSF. Interestingly, BBB efflux transport of GCs, including guanidinoacetate and creatinine, is negligible, though the BBB has a variety of efflux transport systems for synthetic precursors of GCs, such as amino acids and neurotransmitters. Instead, the BCSFB functions as a major cerebral clearance system for GCs. In conclusion, transport of GCs at the BBB and BCSFB appears to be the key determinant of the cerebral levels of GCs, and changes in the transport characteristics may cause the abnormal distribution of GCs in the brain seen

  14. Point-of-Care Technologies for the Advancement of Precision Medicine in Heart, Lung, Blood, and Sleep Disorders.

    Science.gov (United States)

    Bigelow, Mary Emma Gorham; Jamieson, Brian G; Chui, Chi On; Mao, Yufei; Shin, Kyeong-Sik; Huang, Tony Jun; Huang, Po-Hsun; Ren, Liqiang; Adhikari, Bishow; Chen, Jue; Iturriaga, Erin

    2016-01-01

    The commercialization of new point of care technologies holds great potential in facilitating and advancing precision medicine in heart, lung, blood, and sleep (HLBS) disorders. The delivery of individually tailored health care to a patient depends on how well that patient's health condition can be interrogated and monitored. Point of care technologies may enable access to rapid and cost-effective interrogation of a patient's health condition in near real time. Currently, physiological data are largely limited to single-time-point collection at the hospital or clinic, whereas critical information on some conditions must be collected in the home, when symptoms occur, or at regular intervals over time. A variety of HLBS disorders are highly dependent on transient variables, such as patient activity level, environment, time of day, and so on. Consequently, the National Heart Lung and Blood Institute sponsored a request for applications to support the development and commercialization of novel point-of-care technologies through small businesses (RFA-HL-14-011 and RFA-HL-14-017). Three of the supported research projects are described to highlight particular point-of-care needs for HLBS disorders and the breadth of emerging technologies. While significant obstacles remain to the commercialization of such technologies, these advancements will be required to achieve precision medicine. PMID:27602308

  15. Evaluation of electrical aggregometry: comparison with optical aggregometry, secretion of ATP, and accumulation of radiolabeled platelets

    International Nuclear Information System (INIS)

    Platelet aggregation has been most commonly studied in vitro by measuring increases in light transmission as platelets aggregate in PRP. Recently, an electrical impedance method for measuring platelet aggregation has been introduced. This method can be used with either PRP or whole blood and measures an increase in impedance across electrodes placed in the blood samples as platelets accumulate on them. We have compared the results obtained by the two methods, using ADP and collagen as aggregating agents, and also have measured the secretion of platelet ATP simultaneously. Although the aggregometry results were similar, recordings obtained by the electrical method did not distinguish two waves of platelet aggregation or correlate with secretion as well as recordings obtained by the optical method. When PGI2 or PGE1 was added to the PRP, both the rate and extent of the increase in light transmittance were inhibited, but the main effect on the increase in impedance was a decrease in its rate and not in its extent. Increases in impedance and secretion of ATP were also measured in whole blood after the platelets had been labeled with a 125I-containing antibody specific for platelet surface glycoproteins. It appeared that the increases in impedance lagged several minutes behind the formation of platelet aggregates and the secretion of platelet ATP. It is suggested that there are advantages and disadvantages to both methods of measurement of platelet aggregation and that the parameters being measured must be clearly understood to properly interpret the results

  16. A more practical therapy for low platelets.

    Science.gov (United States)

    Torres, G

    1996-01-01

    The Food and Drug Administration (FDA) approved WinRho as a new treatment for ITP or thrombocytopenic purpura (low blood platelet count) in people with HIV. Current treatment options for ITP include AZT, corticosteroids, immunoglobulin therapy, and splenectomy. Clinical evaluation rates AZT as the best of the options. WinRho treatment will not work on Rh-negative patients or patients with no spleen. The largest WinRho study to date, involving 267 patients, shows a mean platelet increase of 76,000 cells with no adverse effect on CD4 counts or evidence of an acceleration of HIV disease progression. HIV-positive patients had a poorer platelet increase response than HIV-negative patients. PMID:11363379

  17. Risks of fresh frozen plasma and platelets.

    Science.gov (United States)

    MacLennan, Sheila; Williamson, Lorna M

    2006-06-01

    Both fresh frozen plasma (FFP) and platelets are heavily used in massive transfusion. Although FFP can partially correct abnormal coagulation, a recent systematic review revealed no randomized trials showing clinical benefit. Although the overall risks of FFP and platelets are low, they are the least safe blood components, due to immunologic reactions such as allergy/anaphylaxis, transfusion-related acute lung injury (TRALI) and hemolysis due to anti-A or anti-B if transfused across ABO groups. TRALI, an acute syndrome of dyspnoea, hypoxia and pulmonary 'white-out' is now a major cause of transfusion-related death. Since it is usually triggered by donor HLA antibodies, selecting non- immune donors for FFP production may be beneficial. For platelet components, risks may be reduced by platelet additive solution, allowing removal of 70% of plasma. Platelets have the additional hazard of bacterial contamination, with donor skin the predominant source. Improved arm cleansing, divert pouches for the first 30-50 mL blood and bacterial screening have been adopted internationally. Virus risks are now vanishingly low, although new agents e.g. West Nile virus can still appear. Pathogen reduction for FFP is now well established in Europe, with solvent detergent and methylene blue methods licensed, and the psoralen amotosalen in trial. Loss of clotting factors and natural anti-coagulants are recognized side effects. Amotosalen is also licensed for platelet concentrates, with the added benefit of bacterial killing. In the UK, concern regarding vCJD has led to importation of US FFP for children. PMID:16763481

  18. Platelet-collagen adhesion enhances platelet aggregation induced by binding of VWF to platelets

    International Nuclear Information System (INIS)

    Ristocetin-induced platelet aggregation (RIPA) was evaluated in the presence of platelet-collagen adhesion. RIPA of normal donor platelet-rich plasma (PRP) demonstrated a primary wave of aggregation mediated by the binding of von Willebrand factor (VWF) to platelets and a secondary aggregation wave, due to a platelet-release reaction, initiated by VWF-platelet binding and inhibitable by acetylsalicylic acid (ASA). An enhanced RIPA was observed in PRP samples to which collagen had been previously added. These subthreshold concentrations of collagen, which by themselves were insufficient to induce aggregation, caused measurable platelet-collagen adhesion. Subthreshold collagen did not cause microplatelet aggregation, platelet release of [3H]serotonin, or alter the dose-responsive binding of 125I-labeled VWF to platelets, which occurred with increasing ristocetin concentrations. However, ASA inhibition of the platelet release reaction prevented collagen-enhanced RIPA. These results demonstrate that platelet-collagen adhesion altered the platelet-release reaction induced by the binding of VWF to platelets causing a platelet-release reaction at a level of VWF-platelet binding not normally initiating a secondary aggregation. These findings suggest that platelet-collagen adhesion enhances platelet function mediated by VWF

  19. Postpartum Blood Clots

    Science.gov (United States)

    ... Infection Postpartum Blood Clots Postpartum Thyroid Disorders Postpartum Depression The risk of developing blood clots (thrombophlebitis) is increased for about 6 to 8 weeks after delivery (see Thromboembolic Disorders During Pregnancy ). Typically, blood clots occur in the deep veins ...

  20. Taurine and platelet aggregation

    International Nuclear Information System (INIS)

    Taurine is a putative neurotransmitter or neuromodulator. The endogenous taurine concentration in human platelets, determined by amino acid analysis, is 15 μM/g. In spite of this high level, taurine is actively accumulated. Uptake is saturable, Na+ and temperature dependent, and suppressed by metabolic inhibitors, structural analogues, and several classes of centrally active substances. High, medium and low affinity transport processes have been characterized, and the platelet may represent a model system for taurine transport in the CNS. When platelets were incubated with 14C-taurine for 30 minutes, then resuspended in fresh medium and reincubated for one hour, essentially all of the taurine was retained within the cells. Taurine, at concentrations ranging from 10-1000 μM, had no effect on platelet aggregation induced by ADP or epinephrine. However, taurine may have a role in platelet aggregation since 35-39% of the taurine taken up by human platelets appears to be secreted during the release reaction induced by low concentrations of either epinephrine or ADP, respectively. This release phenomenon would imply that part of the taurine taken up is stored directly in the dense bodies of the platelet

  1. Mitochondrial activity and oxidative stress markers in peripheral blood mononuclear cells of patients with bipolar disorder, schizophrenia, and healthy subjects.

    Science.gov (United States)

    Gubert, Carolina; Stertz, Laura; Pfaffenseller, Bianca; Panizzutti, Bruna Schilling; Rezin, Gislaine Tezza; Massuda, Raffael; Streck, Emilio Luiz; Gama, Clarissa Severino; Kapczinski, Flávio; Kunz, Maurício

    2013-10-01

    Evidence suggests that mitochondrial dysfunction is involved in the pathophysiology of psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BD). However, the exact mechanisms underlying this dysfunction are not well understood. Impaired activity of electron transport chain (ETC) complexes has been described in these disorders and may reflect changes in mitochondrial metabolism and oxidative stress markers. The objective of this study was to compare ETC complex activity and protein and lipid oxidation markers in 12 euthymic patients with BD type I, in 18 patients with stable chronic SZ, and in 30 matched healthy volunteers. Activity of complexes I, II, and III was determined by enzyme kinetics of mitochondria isolated from peripheral blood mononuclear cells (PBMCs). Protein oxidation was evaluated using the protein carbonyl content (PCC) method, and lipid peroxidation, the thiobarbituric acid reactive substances (TBARS) assay kit. A significant decrease in complex I activity was observed (p = 0.02), as well as an increase in plasma levels of TBARS (p = 0.00617) in patients with SZ when compared to matched controls. Conversely, no significant differences were found in complex I activity (p = 0.17) or in plasma TBARS levels (p = 0.26) in patients with BD vs. matched controls. Our results suggest that mitochondrial complex I dysfunction and oxidative stress play important roles in the pathophysiology of SZ and may be used in potential novel adjunctive therapy for SZ, focusing primarily on cognitive impairment and disorder progression. PMID:23870796

  2. Disorders of the colloid-osmotic blood condition and methods of their correction during angiography in children

    International Nuclear Information System (INIS)

    Results of angiography complication frequency reduction via patient preparation for osmotic stress (that is, introduction of radiopaque media bolus) are presented in the paper. Examination of children aged 5 monthes up to 14 years subjected to angiography under general anestesia has shown that during children preparation for angiography the specific infusion therapy corrects initial colloid-osmotic disorder in blood plasma and prevents action of hyperosmolalic radiopaque media. Occurance of critical values of hyperosmolality and hypooncia is not observed in contrast to control experiments, and it prevents development of some complications

  3. Relationship between changes in the cochlear blood flow and disorder of hearing function induced by blast injury in guinea pigs

    OpenAIRE

    Chen, Wei; Wang, Jianmin; Chen, Jing; Chen, Jichuan; Chen, Zhiqiang

    2013-01-01

    The auditory system is the most susceptible to damages from blast waves. Blast injuries always lead to varying degrees of hearing impairment. Although a disorder of the cochlear blood flow (CoBF) has been considered to be related to many pathological processes of the auditory system and to contribute to various types of hearing loss, changes in the CoBF induced by blast waves and the relationship between such changes and hearing impairment are undefined. To observe the changes in the cochlear...

  4. Effect of Composite Salvia Injection on Platelet Parameters in Children with Anaphylactoid Purpura

    Institute of Scientific and Technical Information of China (English)

    谢雪兰; 寇素茹; 许月红; 李朝英

    2009-01-01

    Objective:To explore the effect of composite salvia injection(CSI) on platelet parameters in children with anaphylactoid purpura(AP) and its clinical significance.Methods:One hundred and fifty children with AP were assigned to two groups,80 in Group A and 70 in Group B.They were treated,respectively,with conventional therapy only or conventional therapy combined with CSI.Their platelet parameters,including blood platelet count(BPC),mean platelet volume(MPV),platelet distribution width(PDW) and plateletcr...

  5. PARot – assessing platelet-rich plasma plus arthroscopic subacromial decompression in the treatment of rotator cuff tendinopathy: study protocol for a randomized controlled trial

    OpenAIRE

    Carr, Andrew; Cooper, Cushla; Murphy, Richard; Watkins, Bridget; Wheway, Kim; Rombach, Ines; Beard, David

    2013-01-01

    Background Platelet-rich plasma (PRP) is an autologous platelet concentrate. It is prepared by separating the platelet fraction of whole blood from patients and mixing it with an agent to activate the platelets. In a clinical setting, PRP may be reapplied to the patient to improve and hasten the healing of tissue. The therapeutic effect is based on the presence of growth factors stored in the platelets. Current evidence in orthopedics shows that PRP applications can be used to accelerate bone...

  6. Pressure-aided transfusion of platelets: does it affect the platelets?

    DEFF Research Database (Denmark)

    Fischer-Nielsen, Anne; Stissing, Trine; Maansson, Charlotte; Joergensen, Bent Gymoese

    2010-01-01

    In massively bleeding patients, pressure infusers are used for transfusion of red blood cells and plasma but not for platelets (PLTs) due to an assumed negative effect on the PLTs. This study examined whether pressure-aided in vitro transfusion affected the number, activation state, and/or functi...

  7. Pressure-aided transfusion of platelets: does it affect the platelets?

    DEFF Research Database (Denmark)

    Fischer-Nielsen, Anne; Stissing, Trine; Maansson, Charlotte; Joergensen, Bent Gymoese

    2010-01-01

    In massively bleeding patients, pressure infusers are used for transfusion of red blood cells and plasma but not for platelets (PLTs) due to an assumed negative effect on the PLTs. This study examined whether pressure-aided in vitro transfusion affected the number, activation state, and/or function...

  8. Migration distance-based platelet function analysis in a microfluidic system.

    Science.gov (United States)

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-01-01

    Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-activated platelets adhered to a collagen-coated surface, causing blood flow to significantly slow and eventually stop. To measure platelet adhesion and aggregation, the migration distance (MD) of blood through the microchannel was monitored. As the microstirrer speed increased, MD initially decreased exponentially but then increased beyond a critical rpm. For platelet-excluded blood samples, there were no changes in MD with increasing stirrer speed. These findings imply that the stirrer provided sufficiently high shear to activate platelets and that blood MD is a potentially valuable index for measuring the shear-dependence of platelet activation. Our microfluidic system is quick and simple, while providing a precise assay to measure the effects of shear on platelet aggregation and adhesion. PMID:24396535

  9. Effect of adhesion proteins and surface chemistry on the procoagulant state of adherent platelets

    Science.gov (United States)

    Grunkemeier, John Mark

    Poor hemocompatibility of a blood contacting device can lead to blood clotting, reduced blood flow, and depletion of platelets from the blood. Improved understanding of the processes by which blood-material contact leads to these responses could result in more hemocompatible materials. Platelets accelerate blood clotting by adhesion, aggregation, secretion of proteins and agonists and acceleration of thrombin generation. Platelets are said to be "procoagulant" after phosphatidylserine residues flip from the cytosolic to the extracellular face of the lipid bilayer. This then allows for the assembly of the prothrombinase complex (Xa, Va and calcium) on the platelet membrane, which can rapidly convert prothrombin to thrombin. In this study, three different methods confirmed that adhesion causes platelets to become procoagulant: shortening of clotting times of recalcified plasma, binding of FITC-annexin V, and generation of thrombin in the presence of Va, Xa and prothrombin by adherent platelets. Adherent platelets were 10--23 times more activated than bulk phase unactivated platelets and 10--24 times less activated than bulk phase platelets activated by calcium ionophore. The role of adsorbed fibrinogen, vWF, mixtures of fibrinogen and vWF, fibronectin, whole and dilute plasma, and plasma deficient in adhesion proteins in stimulating platelet procoagulant activity was investigated. The results of these experiments suggested that adhesion proteins affect procoagulant activation to varying degrees and that surfaces preadsorbed with mixtures of adhesion proteins are more activating that surfaces preadsorbed with single adhesion proteins. The hypothesis that materials that affect tightness of binding of adsorbed adhesion proteins affect platelet procoagulant activity was investigated. These studies showed that increasing fluorine content of RFGD polymerized films caused reduced platelet adhesion, but increased procoagulant activity, possibly due to their ability to adsorb

  10. Characterization of multiple platelet activation pathways in patients with bleeding as a high-throughput screening option: use of 96-well Optimul assay

    OpenAIRE

    Lordkipanidzé, Marie; Lowe, Gillian C.; Kirkby, Nicholas S.; Chan, Melissa V.; Lundberg, Martina H.; Morgan, Neil V.; Bem, Danai; Nisar, Shaista P.; Leo, Vincenzo C.; Jones, Matthew L.; Warner, Timothy D.; Watson, Steve P.; Mumford, Andrew D.; Mundell, Stuart J.; Gissen, Paul

    2014-01-01

    The Optimul 96-well platelet aggregation assay has high levels of sensitivity and specificity for detecting platelet defects.The requirement for a small volume of blood, straightforward nature, and speed make Optimul a promising screening test in bleeding patients.

  11. Patients with previous definite stent thrombosis have a larger fraction of immature platelets and a reduced antiplatelet effect of aspirin

    DEFF Research Database (Denmark)

    Würtz, Morten; Grove, Erik; Wulff, Lise Nielsen; Kaltoft, Anne; Hansen, Hans-Henrik Tilsted; Jensen, Lisette Okkels; Hvas, Anne-Mette; Kristensen, Steen Dalby

    when assessed by multiple electrode aggregometry induced by collagen (pcitrated blood = 0.003; phirudinized blood < 0.0001) and by arachidonic acid (pcitrated blood = 0.16; phirudinized blood = 0.04), respectively. Similarly, platelet aggregation assessed by VerifyNow was higher in ST cases (p = 0...... were treated with aspirin 75 mg once daily. Platelet function was assessed by multiple electrode aggregometry in citrated and hirudinized blood and by VerifyNow Aspirin Assay (Accumetrics, San Diego, California). Flow cytometric determination of the immature platelet fraction was performed to evaluate...... platelet turnover. Platelet activation was evaluated by soluble serum P-selectin. Compliance was confirmed by serum thromboxane B2. Results All patients were fully compliant, which was confirmed by suppressed levels of serum thromboxane B2. Platelet aggregation was increased in patients with previous ST...

  12. Platelet Transfusion and Thrombosis: More Questions than Answers.

    Science.gov (United States)

    Schmidt, Amy E; Refaai, Majed A; Blumberg, Neil

    2016-03-01

    Platelets perform a vital role in hemostasis and their role in inflammation is becoming increasingly evident. Blood transfusion is the most common procedure performed in hospitals and platelet transfusions comprise a significant proportion. Over the past few decades, retrospective studies and randomized clinical trials have demonstrated that blood transfusion is more harmful than previously thought and is associated with numerous complications, such as transfusion-associated lung injury, transfusion-associated cardiac overload, transfusion-associated immune modulation, and infectious diseases such as human immunodeficiency virus, hepatitis C virus, and hepatitis B virus. Recent data suggest an association between platelet transfusion and thrombosis. This review will highlight the mechanistic issues that may be relevant to the epidemiologic associations of platelet transfusion with thrombosis and mortality in critically ill patients. PMID:26716501

  13. The effects of hypercholestrolemia on rabbit platelets: Functional and biochemical alterations

    International Nuclear Information System (INIS)

    Experimental evidence points to hypercholesterolemia as an important risk factor for atherosclerosis and related occlusive vascular disorders. In spite of considerable support implicating cholesterol, the mechanism of its effect on this group of disorders is not entirely clear. Accumulation of fat and cholesterol in the platelets could influence the development of the initial fatty atheromatous lesions in human beings and animals. Since platelets may have a critical role in atherogenesis, we have examined the mechanisms underlying the relationship among platelets, cholesterol, phospholipid metabolism, and platelet function in rabbits fed diets supplemented with cholesterol (1% and 0.5%) and peanut oil (4% and 2%) 1 tab

  14. Increased platelet expression of FcGammaRIIa and its potential impact on platelet reactivity in patients with end stage renal disease

    Directory of Open Access Journals (Sweden)

    Sobel Burton E

    2007-06-01

    Full Text Available Abstract Background Increased platelet reactivity has been implicated in cardiovascular disease – the major cause of death in patients with end stage renal disease (ESRD. FcGammaRIIA is a component of glycoprotein VI and Ib-IX-V that mediate activation of platelets by collagen and von Willebrand factor. To determine whether expression of FcGammaRIIA impacts platelet reactivity we quantified its expression and platelet reactivity in 33 patients with ESRD who were undergoing hemodialysis. Methods Blood samples were obtained from patients immediately before hemodialysis and before administration of heparin. Platelet expression of FcGammaRIIA and the activation of platelets in response to low concentrations of convulxin (1 ng/ml, selected to mimic effects of collagen, thrombin (1 nM, adenosine diphosphate (ADP, 0.2 uM, or platelet activating factor (PAF, 1 nM were determined with the use of flow cytometry in samples of whole blood anticoagulated with corn trypsin inhibitor (a specific inhibitor of Factor XIIa. Results Patients were stratified with respect to the median expression of FcGammaRIIA. Patients with high platelet expression of FcGammaRIIA exhibited 3-fold greater platelet reactivity compared with that in those with low expression in response to convulxin (p Conclusion Increased platelet reactivity in response to low concentrations of diverse agonists is associated with high expression of FcGammaRIIA and may contribute to an increased risk of thrombosis in patients with ESRD.

  15. Platelets in Pulmonary Immune Responses and Inflammatory Lung Diseases.

    Science.gov (United States)

    Middleton, Elizabeth A; Weyrich, Andrew S; Zimmerman, Guy A

    2016-10-01

    Platelets are essential for physiological hemostasis and are central in pathological thrombosis. These are their traditional and best known activities in health and disease. In addition, however, platelets have specializations that broaden their functional repertoire considerably. These functional capabilities, some of which are recently discovered, include the ability to sense and respond to infectious and immune signals and to act as inflammatory effector cells. Human platelets and platelets from mice and other experimental animals can link the innate and adaptive limbs of the immune system and act across the immune continuum, often also linking immune and hemostatic functions. Traditional and newly recognized facets of the biology of platelets are relevant to defensive, physiological immune responses of the lungs and to inflammatory lung diseases. The emerging view of platelets as blood cells that are much more diverse and versatile than previously thought further predicts that additional features of the biology of platelets and of megakaryocytes, the precursors of platelets, will be discovered and that some of these will also influence pulmonary immune defenses and inflammatory injury. PMID:27489307

  16. Radioimmunoassay of platelet proteins

    International Nuclear Information System (INIS)

    The radioimmunoassay of platelet-specific proteins has proven to be an excellent way of monitoring platelet activation in vivo. In contrast to earlier methods such as aggregometry, which has been the major tool used in the evaluation of antiplatelet drugs, the RIAs are capable of working with samples which have been subjected to physiological conditions such as haematocrit, oxygen tension, shear rate and ionized calcium concentration. Also, in contrast to aggregometry, no choice of agonist is necessary. Thus, for the first time it has been possible to monitor the effects of therapeutic intervention with drugs upon the platelet release reaction in vivo. It seems reasonable to equate the release reaction in vivo with activation in vivo, though the stimuli necessarily remain unknown. Nevertheless, the fact that a significant number of the compounds mentioned in Table 3 are indeed capable of reducing platelet activation in vivo and that this effect can be measured objectively is a major step forward in our understanding of platelet pharmacology. Two important goals remain to be achieved, however, the establishment of nonhuman animal models for the evaluation of newer compounds in vivo and longer-term goal of proving in the clinical setting the relevance or otherwise of platelet activation per se to the clinical outcome of a particular disease. In this respect, the availability of accurate, reliable and specific radioimmunoassays has a central role

  17. A composite peripheral blood gene expression measure as a potential diagnostic biomarker in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Peijs, L; Vinberg, M;

    2015-01-01

    40 age- and gender-matched healthy control subjects. Second, a composite gene expression measure was constructed in the first half study sample and independently validated in the second half of the sample. We found downregulation of POLG and OGG1 expression in bipolar disorder patients compared with...... healthy control subjects. In patients with bipolar disorder, upregulation of NDUFV2 was observed in a depressed state compared with a euthymic state. The composite gene expression measure for discrimination between patients and healthy control subjects on the basis of 19 genes generated an area under the...

  18. Evaluation of a BED-SIDE platelet function assay: performance and clinical utility.

    Science.gov (United States)

    Lau, Wei C; Walker, C Ty; Obilby, David; Wash, Mark M; Carville, David G M; Guyer, Kirk E; Bates, Eric R

    2002-01-01

    Platelets have a pivotal role in the initial defense against insult to the vasculature and are also recognized of critical importance in the acute care settings of percutaneous coronary intervention and cardiopulmonary bypass. In these environments both platelet count and function may be markedly compromised. Unfortunately, current assays to evaluate the parameters of platelet count and function are of limited utility for bed-side testing. Moreover, it is suggested that there may be significant inter patient variation in response to antiplatelet therapy that may be exacerbated by other agents (e.g. heparin) that are routinely administered during cardiac intervention. Here we describe a practical, rapid and user-friendly whole blood platelet function assay that has been developed for use in bed-side settings. Platelet agonists were formulated with an anticoagulant and lyophilized in blood collection tubes standardised to receive a l mL fresh whole blood sample. In the presence of an agonist, platelets are activated and interact (aggregate). Using traditional cell counting principles, non-aggregated platelets are counted whereas aggregated platelets are not. The percentage (%) of functional platelets in reference to a baseline tube may then be determined. Results are available within four minutes. Platelet aggregation in whole blood demonstrated good correlation with turbidometric aggregometry for both ADP (r=0.91) and collagen (r=0.88). Moreover, in clinical settings where antiplatelet agents were administered, this rapid, bed-side, platelet function assay demonstrated utility in monitoring patient response to these therapies. This novel bed-side assay of platelet function is extremely suitable for the clinical environment with a rapid turn-around time. In addition, it provides a full haematology profile, including platelet count, and should permit enhancement of transfusion and interventional decisions. PMID:17890800

  19. Platelet-Mediated Metabolism of the Common Dietary Flavonoid, Quercetin

    OpenAIRE

    Wright, Bernice; Gibson, Trevor; Spencer, Jeremy; Lovegrove, Julie A; Gibbins, Jonathan M.

    2010-01-01

    BACKGROUND: Flavonoid metabolites remain in blood for periods of time potentially long enough to allow interactions with cellular components of this tissue. It is well-established that flavonoids are metabolised within the intestine and liver into methylated, sulphated and glucuronidated counterparts, which inhibit platelet function. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate evidence suggesting platelets which contain metabolic enzymes, as an alternative location for flavonoid metabolism...

  20. Platelet Serotonin Transporter Function Predicts Default-Mode Network Activity

    OpenAIRE

    Christian Scharinger; Ulrich Rabl; Christian H. Kasess; Meyer, Bernhard M.; Tina Hofmaier; Kersten Diers; Lucie Bartova; Gerald Pail; Wolfgang Huf; Zeljko Uzelac; Beate Hartinger; Klaudius Kalcher; Thomas Perkmann; Helmuth Haslacher; Andreas Meyer-Lindenberg

    2014-01-01

    Background The serotonin transporter (5-HTT) is abundantly expressed in humans by the serotonin transporter gene SLC6A4 and removes serotonin (5-HT) from extracellular space. A blood-brain relationship between platelet and synaptosomal 5-HT reuptake has been suggested, but it is unknown today, if platelet 5-HT uptake can predict neural activation of human brain networks that are known to be under serotonergic influence. Methods A functional magnetic resonance study was performed in 48 healthy...

  1. Platelet inhibition with Ticlopidine in atherosclerotic intermittent claudication.

    OpenAIRE

    Aukland, A; Hurlow, R. A.; George, A J; Stuart, J

    1982-01-01

    Fifty-one men with atherosclerotic intermittent claudication and haemorheological abnormalities completed a double-blind, one-year randomised trial of Ticlopidine (500 mg/day), a new antiplatelet agent. Ticlopidine caused significant inhibition of platelet aggregation but did not fully correct abnormalities of coagulation, viscosity, and fibrinolysis. There was no significant improvement in walking ability, Doppler ankle-pressure indices, or calf blood flow. Sustained platelet inhibition for ...

  2. Influence of taxol on the response of platelets to chilling.

    OpenAIRE

    White, J. G.

    1982-01-01

    Platelets have a characteristic lenslike appearance in circulating blood. In vitro studies have shown that the discoid shape is supported by a circumferential band of microtubules. Early studies demonstrated that chilling caused platelets to lose their disklike form and become irregularly convoluted with multiple pseudopods. The cold-induced shape change was associated with disappearance of the annular band of microtubules. Rewarming caused reassembly of the circumferential bundle and recover...

  3. Child who presented with hematohidrosis (sweating blood) with oppositional defiant disorder

    OpenAIRE

    Deshpande, Manjiri; Indla, Vishal; Kumar, Varinder; Reddy, Indla Ramasubba

    2014-01-01

    Hematohidrosis is a very rare condition of sweating blood. A child's case who presented to us with hematohidrosis is reported. There are only few reports in the literature. A 10-year-old boy presented to our hospital with a history of repeated episodes of oozing of blood from navel, eyes, ear lobules, and nose. During the examination, it disappeared as soon as it was mopped leaving behind no sign of trauma only to reappear within a few seconds. Bleeding time, clotting time, and prothrombin ti...

  4. Use of autologous /sup 111/In-labelled platelets and scintigraphy to illustrate enhanced platelet activity during erection in the chacma baboon

    Energy Technology Data Exchange (ETDEWEB)

    Dormehl, I.C.; Du Plessis, M.; Maree, M.; Bornman, M.S.; Du Plessis, D.J.

    1984-12-01

    The demonstration of thrombelastographic hypercoagulability in the penile blood during erection, and the accompanying deposition of fibrin onto the endothelial layer of the deep penile artery and trabecular surface inspired this investigation of the possible role that platelets might play in the process. The bloodpooling pattern in the penis during and after erection from electro-stimulation was studied in 9 male adult baboons (Papio ursinus) using in vivo sup(99m)Tc-labelled red blood cells and scintigraphy. Platelet activity was similarly investigated after administering autologous /sup 111/In-labelled platelets to the baboons. The results indicate an enhanced platelet concentration with respect to blood-pooling during erection, and an entrapment of platelets after erection.

  5. The use of autologous 111In-labelled platelets and scintigraphy to illustrate enhanced platelet activity during erection in the chacma baboon

    International Nuclear Information System (INIS)

    The demonstration of thrombelastographic hypercoagulability in the penile blood during erection, and the accompanying deposition of fibrin onto the endothelial layer of the deep penile artery and trabecular surface inspired this investigation of the possible role that platelets might play in the process. The bloodpooling pattern in the penis during and after erection from electro-stimulation was studied in 9 male adult baboons (Papio ursinus) using in vivo sup(99m)Tc-labelled red blood cells and scintigraphy. Platelet activity was similarly investigated after administering autologous 111In-labelled platelets to the baboons. The results indicate an enhanced platelet concentration with respect to blood-pooling during erection, and an entrapment of platelets after erection. (orig.)

  6. Endothelial and platelet markers in diabetes mellitus type 2

    Institute of Scientific and Technical Information of China (English)

    Peter Kubisz; Lucia Stanciaková; Ján Stasko; Peter Galajda; Marián Mokáň

    2015-01-01

    Diabetes mellitus (DM) is an extremely common disorder which carries a risk of vascular impairment. DM type2 (DM2) can be characterized by the dysfunction ofhaemostasis manifesting by stimulated coagulation process,disorder of platelet function and decreased fibrinolyticactivity. These all are the reasons why DM2 is the mostcommon acquired thrombophilia. Endothelial dysfunctionalong with platelet hyperactivity are unquestionablyinvolved in the hyperactivation of platelets and clottingfactors in DM. As a natural consequence of continuousinvestigation, many markers of endothelial dysfunctionand diabetic thrombocytopathy have been identifiedand considered for implementation in clinical practice.Endothelial function can be assessed by the evaluationof endothelial markers, circulating molecules synthesisedin various amounts by the endothelium. These markersprecede the signs of evident microangiopathy. Plateletshave an ethiopathogenic relation to the microangiopathy inDM. Their increased activity was confirmed in both typesof DM. Predictors of endothelial and platelet disorder couldimprove the screening of individuals at increased risk, thusleading to the early diagnosis, appropriate treatment, aswell as to the effective prevention of the complications ofDM2. In the article we deal with the mechanisms involvedin the pathogenesis of endothelial and platelet functionalabnormalities, endothelial and platelet markers of DM2considered for implementation in clinical practice andpossibilities of their detection.

  7. Disruption in the Blood-Brain Barrier: The Missing Link between Brain and Body Inflammation in Bipolar Disorder?

    Directory of Open Access Journals (Sweden)

    Jay P. Patel

    2015-01-01

    Full Text Available The blood-brain barrier (BBB regulates the transport of micro- and macromolecules between the peripheral blood and the central nervous system (CNS in order to maintain optimal levels of essential nutrients and neurotransmitters in the brain. In addition, the BBB plays a critical role protecting the CNS against neurotoxins. There has been growing evidence that BBB disruption is associated with brain inflammatory conditions such as Alzheimer’s disease and multiple sclerosis. Considering the increasing role of inflammation and oxidative stress in the pathophysiology of bipolar disorder (BD, here we propose a novel model wherein transient or persistent disruption of BBB integrity is associated with decreased CNS protection and increased permeability of proinflammatory (e.g., cytokines, reactive oxygen species substances from the peripheral blood into the brain. These events would trigger the activation of microglial cells and promote localized damage to oligodendrocytes and the myelin sheath, ultimately compromising myelination and the integrity of neural circuits. The potential implications for research in this area and directions for future studies are discussed.

  8. Blood glucose regulation mechanism in depressive disorder animal model during hyperglycemic states.

    Science.gov (United States)

    Lim, Su-Min; Park, Soo-Hyun; Sharma, Naveen; Kim, Sung-Su; Lee, Jae-Ryeong; Jung, Jun-Sub; Suh, Hong-Won

    2016-06-01

    Depression is more common among diabetes people than in the general population. In the present study, blood glucose change in depression animal model was characterized by various types of hyperglycemia models such as d-glucose-fed-, immobilization stress-, and drug-induced hyperglycemia models. First, the ICR mice were enforced into chronic restraint stress for 2h daily for 2 weeks to produce depression animal model. The animals were fed with d-glucose (2g/kg), forced into restraint stress for 30min, or administered with clonidine (5μg/5μl) supraspinally or spinally to produce hyperglycemia. The blood glucose level in depression group was down-regulated compared to that observed in the normal group in d-glucose-fed-, restraint stress-, and clonidine-induced hyperglycemia models. The up-regulated corticosterone level induced by d-glucose feeding or restraint stress was reduced in the depression group while the up-regulation of plasma corticosterone level is further elevated after i.t. or i.c.v. clonidine administration in the depression group. The up-regulated insulin level induced by d-glucose feeding or restraint stress was reduced in the depression group. On the other hand, blood corticosterone level in depression group was up-regulated compared to the normal group after i.t. or i.c.v. clonidine administration. Whereas the insulin level in depression group was not altered when mice were administered clonidine i.t. or i.c.v. Our results suggest that the blood glucose level in depression group is down-regulated compared to the normal group during d-glucose-fed-, immobilization stress-, and clonidine-induced hyperglycemia in mice. The down-regulation of the blood glucose level might be one of the important pathophysiologic changes in depression. PMID:27034116

  9. Ultraviolet irradiation effect on human platelet function

    International Nuclear Information System (INIS)

    Treatment of human blood platelets with ultraviolet light (uv) results in changes of several physiological functions. When uv-treated platelets are stirred in the presence of fibrinogen and calcium ions aggregation occurs. The amount of aggregation is dependent upon the uv dosage and wavelength, the fibrinogen concentration and the calcium concentration. Maximum aggregation occurs with a 250 joule/m2 dosage at 245 nm wavelength in the presence of 0.5 mg/ml fibrinogen and 2 mM calcium ion. Aggregation induced by uv is partially inhibited by apyrase or by metabolic inhibitors. Hirudin, a potent inhibitor of thrombin action, did not inhibit uv-induced aggregation. Pretreatment with uv decreases the ability of platelets to support clot retraction. An action spectrum for the effect has maxima at 210 nm and at 280 nm indicating the chromophore is a protein containing aromatic amino acids. Dosages greater than 120 seconds of exposure to a Hanovia High-Pressure Quartz Mercury-Vapor Lamp render the platelets incapable of supporting retraction of fibrin clots induced by thrombin. Irradiation with 250 nm uv has the ability to stimulate retraction of fibrin clots induced by reptilase. Thrombin-mediated platelet functions, including binding, release and aggregation are also inhibited by uv irradiation. The number of binding sites per platelet is reduced by 43 percent with a 90 second dose of uv. For the same dose, the total amount of serotonin released is decreased from 81 percent to 41 percent while the thrombin-induced aggregation is completely inhibited. An action spectra contains two maxima, at 245 nm and 280 nm. The effect of uv is compared with the effect of dithiothreitol (DTT) as a test of the hypothesis that uv-induced aggregation is mediated by disulfide bond disruption

  10. Blood Clotting and Pregnancy

    Medline Plus

    Full Text Available ... Housing Travel Information Government Concierge View all meetings Publications Blood Current Issue First Edition Abstracts Blood Advances ... reflect the most recent scientific research View all publications For Patients Blood Basics Blood Disorders Anemia Bleeding ...

  11. Platelets and cardiac arrhythmia

    Directory of Open Access Journals (Sweden)

    JonasSDe Jong

    2010-12-01

    Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.

  12. Extracorporeal irradiation of calves blood. Effects on: the lymphocytes, the blood-platelet function, seric proteins, and fibrinogen; Irradiation extracorporelle du sang de veau effets sur: les lymphocytes, la fonction plaquettaire, les proteines seriques et le fibrinogene

    Energy Technology Data Exchange (ETDEWEB)

    Hollard, D.; Suscillon, M.; Benabid, Y.; Concord, E.; Ivanoff, M.; Laurent, M.; Rambaud, F. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    The present paper reports the results obtained after extracorporeal irradiation of circulating blood of calves. Animals are divided in 3 groups as follows: - control animals: blood circulation without irradiation; - calves which received 40000 rads during 24 hours of continuous irradiation; - calves which received the same dose, during a period of 5 days (5 hours every day). The more interesting results are: - the early lymphopenia which persists for 7 or 8 weeks and may be in relationship with the change of immunoglobulins; - a constant hyperfibrinemia (12 g/l) never reported, as far as we know, by authors using I.E.C. Several hypothesis are advanced to explain this phenomenon. (authors) [French] Ce travail presente l'ensemble des resultats hematologiques obtenus apres irradiation extracorporelle du sang de veaux repartis en 3 series: - veaux temoins: circulation du sang sans irradiation - veaux soumis a une irradiation continue dose globale integree de 40000 rads en 24 heures; - veaux ayant recu la meme dose globale en irradiation fractionnee repartie sur 5 jours (5 heures par jour). Les resultats les plus marquants sont d'une part une lymphopenie precoce se prolongeant durant 7 a 8 semaines et qui pourrait etre reliee aux modifications observees sur les immunoglobulines. D'autre part une hyperfibrinemie (12 g/l) constante, apparemment jamais signalee par d'autres auteurs utilisant l'I.E.C. Plusieurs hypotheses explicatives de ce phenomene sont exposees et sont a l'etude. (auteurs)

  13. Metabolomics as a tool for discovery of biomarkers of autism spectrum disorder in the blood plasma of children.

    Directory of Open Access Journals (Sweden)

    Paul R West

    Full Text Available The diagnosis of autism spectrum disorder (ASD at the earliest age possible is important for initiating optimally effective intervention. In the United States the average age of diagnosis is 4 years. Identifying metabolic biomarker signatures of ASD from blood samples offers an opportunity for development of diagnostic tests for detection of ASD at an early age.To discover metabolic features present in plasma samples that can discriminate children with ASD from typically developing (TD children. The ultimate goal is to identify and develop blood-based ASD biomarkers that can be validated in larger clinical trials and deployed to guide individualized therapy and treatment.Blood plasma was obtained from children aged 4 to 6, 52 with ASD and 30 age-matched TD children. Samples were analyzed using 5 mass spectrometry-based methods designed to orthogonally measure a broad range of metabolites. Univariate, multivariate and machine learning methods were used to develop models to rank the importance of features that could distinguish ASD from TD.A set of 179 statistically significant features resulting from univariate analysis were used for multivariate modeling. Subsets of these features properly classified the ASD and TD samples in the 61-sample training set with average accuracies of 84% and 86%, and with a maximum accuracy of 81% in an independent 21-sample validation set.This analysis of blood plasma metabolites resulted in the discovery of biomarkers that may be valuable in the diagnosis of young children with ASD. The results will form the basis for additional discovery and validation research for 1 determining biomarkers to develop diagnostic tests to detect ASD earlier and improve patient outcomes, 2 gaining new insight into the biochemical mechanisms of various subtypes of ASD 3 identifying biomolecular targets for new modes of therapy, and 4 providing the basis for individualized treatment recommendations.

  14. Food intake and blood cholesterol levels of community-based adults with mood disorders

    Directory of Open Access Journals (Sweden)

    Davison Karen M

    2012-02-01

    Full Text Available Abstract Background A growing body of literature links nutrition to mood, especially in epidemiological surveys, but there is little information characterizing food intake in people with diagnosed mood disorders. Methods Food intake obtained from 3-day food records was evaluated in 97 adults with mood disorders, whose diagnoses were confirmed in structured interviews. Information from a population nutrition survey, national guidelines for nutritional intakes (Eating Well with Canada's Food Guide and North American dietary guidelines (Dietary Reference Intakes was utilized to evaluate the quality of their food intake. Results Compared to the regional nutrition survey data and national guidelines, a greater proportion of study participants consumed fewer of the recommended servings of grains (p p p p p p 5.2 and ≤ 6.2 mmol/L and 21% had hypercholesterolemia (> 6.2 mmol/L. Conclusions Much research has proposed multiple ways in which healthier diets may exert protective effects on mental health. The results of this study suggest that adults with mood disorders could benefit from nutritional interventions to improve diet quality.

  15. CONGESTIVE HEART FAILURE IN DOGS IS ASSOCIATED WITH INCREASED PLATELET LEUKOCYTE AGGREGATION MEASURED BY FLOW CYTOMETRY

    DEFF Research Database (Denmark)

    Tarnow, Inge; Andreasen, Susanne SH; Olsen, Lisbeth Høier; Moesgaard, Sophia Gry; Rasmussen, Caroline Elisabeth; Kristensen, Annemarie Thuri; Falk, Bo Torkel

    2010-01-01

    binding),monocyte-platelet (MPAs) and neutrophil-platelet aggregates (NPAs) defined as leukocytes positive for CD61 were measured by whole blood flow cytometry asmarkers of platelet activation. For every dog platelet activation was assessed in unstimulated samples, and in response to exogenously added......CONGESTIVE HEART FAILURE IN DOGS IS ASSOCIATED WITH ENHANCED PLATELET-LEUKOCYTE AGGREGATES - A MARKER FOR PLATELET ACTIVATION. I Tarnow1, LH Olsen2, SHS Andreasen2, SG Moesgaard2, CE Rasmussen2, AT Kristensen1, T Falk2. 1Departments of Small Animal Clinical Sciences and 2Animal and Veterinary Basic...... adenosine diphosphate (ADP), thrombin and a synthetic thromboxane A2 analogue 1 epinephrine. Complete blood count and biochemical screening were performed in all dogs. Dogs with CHF had higher MPAs (p 5 0.014) and NPAs ( p 5 0.021) compared to controls (2-way analysis of variance for repeated measurements)....

  16. Platelets stimulate fibroblast-mediated contraction of collagen gels

    Directory of Open Access Journals (Sweden)

    Lundahl Joachim

    2003-10-01

    Full Text Available Abstract Background Platelets are thought to play a role in a variety of inflammatory conditions in the lung, some of which may lead to fibrosis. In the current study we tested the hypothesis that whole platelets and platelet lysate can mediate remodelling of extracellular matrix in vitro by affecting fibroblast-mediated contraction of a collagen gel. We also sought to determine to what extent platelet-derived growth factor (PDGF and transforming growth factor-β (TGF-β contribute to this effect. Methods Washed platelets, isolated from healthy blood donors, and platelet lysate (freezing and thawing, were cast together with human lung fibroblasts in three-dimensional collagen gels. The gels were then released and cultured for four days. PDGF and TGF-β1 concentrations were measured in culture supernatants by ELISA. Results Both platelets and platelet lysate augmented fibroblast-mediated gel contraction in a time and concentration dependent manner (19.9% ± 0.1 (mean ± SEM of initial area vs. 48.0% ± 0.4 at 48 hours; P 1 and PDGF-AA/AB were released in co-culture. PDGF-AA/AB had a maximum release at 24 hours whereas TGF-β1 release increased with longer culture periods. Neutralising antibodies to these mediators partially inhibited platelet-induced gel contraction. Conclusion We conclude that platelets may promote remodelling of extracellular matrix in vitro and that PDGF and TGF-β partially mediate this effect, also indicating a role for other mediators. The findings may be an important mechanism in regulating repair processes after injury.

  17. Effects of the breed, sex and age on cellular content and growth factor release from equine pure-platelet rich plasma and pure-platelet rich gel

    OpenAIRE

    Giraldo Carlos E; López Catalina; Álvarez María E; Samudio Ismael J; Prades Marta; Carmona Jorge U

    2013-01-01

    Abstract Background There is no information on the effects of the breed, gender and age on the cellular content and growth factor (GF) release from equine pure-platelet rich plasma (P-PRP) and pure-platelet rich gel (P-PRG). The objectives of this study were: 1) to compare the cellular composition of P-PRP with whole blood and platelet poor plasma (PPP); 2) to compare the concentration of transforming GF beta 1 (TGF-β1) and platelet derived GF isoform BB (PDGF-BB) between P-PRP treated with n...

  18. Circulating endothelial progenitor cell and platelet microparticle impact on platelet activation in hypertension associated with hypercholesterolemia.

    Directory of Open Access Journals (Sweden)

    Nicoleta Alexandru

    Full Text Available AIM: The purpose of this project was to evaluate the influence of circulating endothelial progenitor cells (EPCs and platelet microparticles (PMPs on blood platelet function in experimental hypertension associated with hypercholesterolemia. METHODS: Golden Syrian hamsters were divided in six groups: (i control, C; (ii hypertensive-hypercholesterolemic, HH; (iii 'prevention', HHin-EPCs, HH animals fed a HH diet and treated with EPCs; (iv 'regression', HHfin-EPCs, HH treated with EPCs after HH feeding; (v HH treated with PMPs, HH-PMPs, and (vi HH treated with EPCs and PMPs, HH-EPCs-PMPs. RESULTS: Compared to HH group, the platelets from HHin-EPCs and HHfin-EPCs groups showed a reduction of: (i activation, reflected by decreased integrin 3β, FAK, PI3K, src protein expression; (ii secreted molecules as: SDF-1, MCP-1, RANTES, VEGF, PF4, PDGF and (iii expression of pro-inflammatory molecules as: SDF-1, MCP-1, RANTES, IL-6, IL-1β; TFPI secretion was increased. Compared to HH group, platelets of HH-PMPs group showed increased activation, molecules release and proteins expression. Compared to HH-PMPs group the combination EPCs with PMPs treatment induced a decrease of all investigated platelet molecules, however not comparable with that recorded when EPC individual treatment was applied. CONCLUSION: EPCs have the ability to reduce platelet activation and to modulate their pro-inflammatory and anti-thrombogenic properties in hypertension associated with hypercholesterolemia. Although, PMPs have several beneficial effects in combination with EPCs, these did not improve the EPC effects. These findings reveal a new biological role of circulating EPCs in platelet function regulation, and may contribute to understand their cross talk, and the mechanisms of atherosclerosis.

  19. Pseudo (Platelet-type) von Willebrand disease in pregnancy: a case report

    OpenAIRE

    Grover Neetu; Boama Vincent; Chou Munazzah Rifat

    2013-01-01

    Abstract Background Pseudo (platelet-type)-von Willebrand disease is a rare autosomal dominant bleeding disorder caused by an abnormal function of the glycoprotein lb protein; the receptor for von Willebrand factor. This leads to an increased removal of VWF multimers from the circulation as well as platelets and this results in a bleeding diathesis. Worldwide, less than 50 patients are reported with platelet type von Willebrand disease (PT-VWD). Case presentation We describe the management of...

  20. A meta-analysis and genome-wide association study of platelet count and mean platelet volume in african americans.

    Directory of Open Access Journals (Sweden)

    Rehan Qayyum

    Full Text Available Several genetic variants associated with platelet count and mean platelet volume (MPV were recently reported in people of European ancestry. In this meta-analysis of 7 genome-wide association studies (GWAS enrolling African Americans, our aim was to identify novel genetic variants associated with platelet count and MPV. For all cohorts, GWAS analysis was performed using additive models after adjusting for age, sex, and population stratification. For both platelet phenotypes, meta-analyses were conducted using inverse-variance weighted fixed-effect models. Platelet aggregation assays in whole blood were performed in the participants of the GeneSTAR cohort. Genetic variants in ten independent regions were associated with platelet count (N = 16,388 with p<5×10(-8 of which 5 have not been associated with platelet count in previous GWAS. The novel genetic variants associated with platelet count were in the following regions (the most significant SNP, closest gene, and p-value: 6p22 (rs12526480, LRRC16A, p = 9.1×10(-9, 7q11 (rs13236689, CD36, p = 2.8×10(-9, 10q21 (rs7896518, JMJD1C, p = 2.3×10(-12, 11q13 (rs477895, BAD, p = 4.9×10(-8, and 20q13 (rs151361, SLMO2, p = 9.4×10(-9. Three of these loci (10q21, 11q13, and 20q13 were replicated in European Americans (N = 14,909 and one (11q13 in Hispanic Americans (N = 3,462. For MPV (N = 4,531, genetic variants in 3 regions were significant at p<5×10(-8, two of which were also associated with platelet count. Previously reported regions that were also significant in this study were 6p21, 6q23, 7q22, 12q24, and 19p13 for platelet count and 7q22, 17q11, and 19p13 for MPV. The most significant SNP in 1 region was also associated with ADP-induced maximal platelet aggregation in whole blood (12q24. Thus through a meta-analysis of GWAS enrolling African Americans, we have identified 5 novel regions associated with platelet count of which 3 were replicated in other ethnic

  1. Platelet-Stored Angiogenesis Factors: Clinical Monitoring Is Prone to Artifacts

    OpenAIRE

    Patrick Starlinger; Lejla Alidzanovic; Dominic Schauer; Philipp Brugger; Silvia Sommerfeldt; Irene Kuehrer; Schoppmann, Sebastian F; Michael Gnant; Christine Brostjan

    2011-01-01

    Background: The analysis of angiogenesis factors in the blood of tumor patients has given diverse results on their prognostic or predictive value. Since mediators of angiogenesis are stored in platelets, their measurement in plasma is sensitive to inadvertent platelet activation during blood processing. Methods: Variants of blood withdrawal and plasma preparation were evaluated by ELISA for the detection of TSP-1, PF-4, VEGF and PD-ECGF. A total of 22 pancreatic cancer patients and 29 healthy...

  2. Diagnostic value of platelet derived growth factor-BB, transforming growth factor-β1,matrix metalloproteinase-1, and tissue inhibitor of matrix metalloproteinase-1 in serum and peripheral blood mononuclear cells for hepatic fibrosis

    Institute of Scientific and Technical Information of China (English)

    Bin-Bin Zhang; Wei-Min Cai; Hong-Lei Weng; Zhong-Rong Hu; Jun Lu; Min Zheng; Rong-Hua Liu

    2003-01-01

    AIM: Noninvasive diagnosis of hepatic fibrosis has become the focus because of the limited biopsy, especially in the surveillance of treatment and in screening hepatic fibrosis.Recently, regulatory elements involved in liver fibrosis, such as platelet derived growth factor-BB (PDGF-BB), transforming growth factor-β1 (TGF-β1), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), have been studied extensively. To determine whether these factors or enzymes could be used as the indices for the diagnosis of hepatic fibrosis, we investigated them by means of receiver operating characteristic (ROC) curve.METHODS: Serum samples from sixty patients with chronic viral hepatitis B and twenty healthy blood donors were assayed to determine the level of PDGF-BB, TGF-β1, MMP-1, and TIMP-1 with ELISA, and HA, PCIII, C-IV, and LN level with RIA. The message RNA (mRNA) expression of TIMP-1 and MMP-1 in peripheral blood mononuclear cells (PBMCs) was detected by RT-PCR and Northern blot hybridization. Liver biopsy was performed in all patients.The biopsy samples were histopathologically examined. The trial was double-blind controlled.RESULTS: The serum level of PDGF-BB, TIMP-1, the ratio of TIMP-1 and MMP-1 (TIMP-1/MMP-1), mRNA expression of TIMP-1 (TIMP-1mRNA), and the ratio of TIMP-1mRNA and MMP-1mRNA (TIMP-1mRNA/MMP-1mRNA) in patients was significantly higher than those in the healthy blood donors (t=2.514-11.435, P=0.000-0.016). The serum level of PDGF-BB, TIMP-1, TIMP-1/MMP-1, and TIMP-1mRNA was positively correlated with fibrosis stage and inflammation grade (r=0.239-0.565, P=0.000-0.033), while the serum level of MMP-1 was negatively correlated with fibrosis stage and inflammation grade, and TIMP-1mRNA/MMP-1mRNA was positively correlated with inflammation grade. Through the analysis by ROC curve, serum PDGF-BB was the most valuable marker, and its sensitivity was the highest among the nine indices. The markers with the highest

  3. Selective Cumulative Inhibition of Platelet Thromboxane Production by Low-dose Aspirin in Healthy Subjects

    OpenAIRE

    Patrignani, Paola; Filabozzi, Paola; Patrono, Carlo

    1982-01-01

    Acetylation of platelet cyclooxygenase by oral aspirin is dose dependent and cumulative with repeated administration. However, no single dose of aspirin has been found to be completely selective of platelet thromboxane (TX) synthesis inhibition in man. We determined the dose dependence, cumulative nature and selectivity of aspirin effects on platelet TXB2 and renal prostaglandin (PG) and prostacyclin (PGI2) production. We measured, by radioimmunoassay, serum TXB2 levels after whole blood clot...

  4. Evaluation of reticulated platelets in dogs with breed-related thrombocytopenia.

    Science.gov (United States)

    Zmigrodzka, M; Guzera, M; Winnicka, A

    2014-01-01

    The aim of this study was to evaluate the percentage of reticulated platelets in healthy dogs with breed-related thrombocytopenia. Seventy two dogs, clinically healthy, were enrolled in the study. Blood was collected from the patients and anticoagulated with tripotassium ethylenediaminetetraacetic acid (K3-EDTA) and sodium citrate. Platelet count was obtained by an impedance haematology analyser and platelet morphology was evaluated by examination of blood smears. Patients were allocated into two groups. Group 1 consisted of 30 dogs with normal platelet count, whereas group 2 was composed of 42 dogs with thrombocytopenia. Thrombocytopenia was present in both K3-EDTA and citrate blood samples. Patients with thrombocytopenia were divided into two subgroups: the first subgroup included dogs with platelet count in K3-EDTA anticoagulated blood from 100 to 200 x10(9)/L, patients in the second subgroup had a platelet count of less than 100 x10(9)/L. The percentage of young reticulated platelets (RPs) labelled with thiazole orange, and the percentage of platelets coated with platelet surface-associated IgG, were determined in platelet-rich plasma (PRP) by a flow cytometer. The mean percentage of RPs in K3-EDTA and citrate PRP was significantly higher in dogs with thrombocytopenia than in dogs with normal platelet count. The mean percentage of RPs was significantly higher in citrate PRP than in K3-EDTA PRP in all groups. The results suggest that idiopathic, asymptomatic thrombocytopenia is not caused by platelet surface-associated IgG. Dogs with breed-related thrombocytopenia have a competent bone marrow. PMID:24724481

  5. Platelet Vascular Endothelial Growth Factor is a Potential Mediator of Transfusion-Related Acute Lung Injury

    OpenAIRE

    Maloney, James P.; Ambruso, Daniel R.; Norbert F. Voelkel; Silliman, Christopher C

    2014-01-01

    Objective The occurrence of non-hemolytic transfusion reactions is highest with platelet and plasma administration. Some of these reactions are characterized by endothelial leak, especially transfusion related acute lung injury (TRALI). Elevated concentrations of inflammatory mediators secreted by contaminating leukocytes during blood product storage may contribute to such reactions, but platelet-secreted mediators may also contribute. We hypothesized that platelet storage leads to accumulati...

  6. Migration distance-based platelet function analysis in a microfluidic system

    OpenAIRE

    Song, Suk-Heung; Lim, Chae-Seung; Shin, Sehyun

    2013-01-01

    Aggregation and adhesion of platelets to the vascular wall are shear-dependent processes that play critical roles in hemostasis and thrombosis at vascular injury sites. In this study, we designed a simple and rapid assay of platelet aggregation and adhesion in a microfluidic system. A shearing mechanism using a rotating stirrer provided adjustable shear rate and shearing time and induced platelet activation. When sheared blood was driven through the microchannel under vacuum pressure, shear-a...

  7. Relationships between optical aggregometry (type Born) and flow cytometry in evaluating ADP-induced platelet activation

    OpenAIRE

    Sbrana, Silverio; Della Pina, Francesca; Rizza, Antonio; Buffa, Manuela; De Filippis, Rossella; Gianetti, Jacopo; Clerico, Aldo

    2008-01-01

    Background: Platelet response to activating agents is used to monitor the efficacy of anti-aggregation therapies. The aim of our study has been to demonstrate the existence of relationships between early events of ADP-induced platelet activation, measured by flow cytometry and platelet-rich plasma aggregation,quantified by optical aggregometry. Methods: We evaluated peripheral blood of 12 donors. The following parameters were quantified by cytometry after stimulation with adenosine diphosphat...

  8. The effects of vincristine on platelet aggregation studied by a filter loop technique in the rat.

    OpenAIRE

    Bee, D; Leach, E.; Martin, J. F.; Suggett, A. J.

    1980-01-01

    1 A method for measuring aggregation of platelets of adenosine diphosphate (ADP) is described using a filter inserted into the flowing aortic blood in the rat. 2 Repeated infusions of ADP resulted in a fall in the calculated aggregation index without significant changes in the platelet count. 3 Vincristine (0.05 mg/kg) intravenously caused significant inhibition of ADP-induced platelet aggregation. 4 Infusion of ADP caused some peripheral vasodilatation though it is unlikely that this contrib...

  9. The role of von Willebrand factor and fibrinogen in platelet aggregation under varying shear stress.

    OpenAIRE

    Y. Ikeda; Handa, M; Kawano, K; Kamata, T; Murata, M.; Araki, Y; Anbo, H; Kawai, Y; Watanabe, K.; Itagaki, I

    1991-01-01

    Exposure of platelets to shear stress leads to aggregation in the absence of exogenous agonists. We have now found that different adhesive proteins and platelet membrane glycoproteins are involved in aggregation depending on the shear stress conditions and the concentration of divalent cations in the medium. When blood is collected with trisodium citrate as anticoagulant, which causes a decrease in the levels of external ionized calcium ([Ca2+]o), platelet aggregation can be induced under low...

  10. Intravascular filarial parasites inhibit platelet aggregation. Role of parasite-derived prostanoids.

    OpenAIRE

    L. X. Liu; Weller, P F

    1992-01-01

    The nematode parasites that cause human lymphatic filariasis survive for long periods in their vascular habitats despite continual exposure to host cells. Platelets do not adhere to blood-borne microfilariae, and thrombo-occlusive phenomena are not observed in patients with circulating microfilariae. We studied the ability of microfilariae to inhibit human platelet aggregation in vitro. Brugia malayi microfilariae incubated with human platelets caused dose-dependent inhibition of agonist-indu...

  11. Lessons in platelet production from inherited thrombocytopenias.

    Science.gov (United States)

    Pecci, Alessandro; Balduini, Carlo L

    2014-04-01

    Our knowledge of the cellular and molecular mechanisms of platelet production has greatly expanded in recent years due to the opportunity to culture in vitro megakaryocytes and to create transgenic animals with specific genetic defects that interfere with platelet biogenesis. However, in vitro models do not reproduce the complexity of the bone marrow microenvironment where megakaryopoiesis takes place, and experience shows that what is seen in animals does not always happen in humans. So, these experimental models tell us what might happen in humans, but does not assure us that these events really occur. In contrast, inherited thrombocytopenias offer the unique opportunity to verify in humans the actual effects of abnormalities in specific molecules on platelet production. There are currently 20 genes whose defects are known to result in thrombocytopenia and, on this basis, this review tries to outline a model of megakaryopoiesis based on firm evidence. Inherited thrombocytopenias have not yet yielded all the information they can provide, because nearly half of patients have forms that do not fit with any known disorder. So, further investigation of inherited thrombocytopenias will advance not only the knowledge of human illnesses, but also our understanding of human platelet production. PMID:24480030

  12. A computerized multichannel platelet aggregometer system.

    Science.gov (United States)

    Kuzara, D; Zoltan, B J; Greathouse, S L; Jordan, C W; Kohler, C A

    1986-08-01

    Commercially available instrumentation for conducting platelet aggregation studies in clinical and research laboratories consists of one-, two-, or four-channel aggregometers used in conjunction with strip chart recorders. These instruments have limited utility in large-scale drug screening and evaluation of the mode of action of drugs or in the clinical diagnosis of platelet disorders. A new instrument, a computerized multichannel aggregometer system (CMPAS) has been developed to collect, display, and analyze platelet aggregation data. The system is comprised of a 24-channel Born-type aggregometer, interfaced to a Rockwell AIM-65 microcomputer through an analogue-to-digital converter and an Epson dot-matrix printer. Each channel is individually calibrated, and aggregation data can be collected on up to 24 different platelet-rich plasma samples simultaneously. Conversational programs written in BASIC prompt the user for the addition of agonists and inhibitors. The tracings for each channel are displayed simultaneously, and a program automatically analyzes the data to generate the following parameters: baseline optical density, maximum aggregation response, positive and negative slopes, time to peak aggregation, and percentage response. Computerized multichannel aggregometer system data outputs are comparable to data generated by a standard Chronolog aggregometer unit. The advantages of the system include multichannel capability, simultaneous display of all channels allowing relative comparisons between control and experimental groups, and time savings and improved efficiency in conducting and analyzing aggregation experiments. PMID:3755779

  13. Incidence of platelet dysfunction by thromboelastography-platelet mapping in children supported with ECMO: A Pilot Retrospective Study.

    Directory of Open Access Journals (Sweden)

    Arun eSaini

    2016-01-01

    Full Text Available Background: Bleeding complications are common and decrease the odds of survival in children supported with extracorporeal membrane oxygenation (ECMO. The role of platelet dysfunction on ECMO-induced coagulopathy and resultant bleeding complications is not well understood. The primary objective of this pilot study was to determine the incidence and magnitude of platelet dysfunction according to thromboelastography (TEG®-platelet mapping (PM testing. Methods: Retrospective chart review of children <18 years old who required ECMO at a tertiary level hospital. We collected TEG®-PM and conventional coagulation tests data. We also collected demographic, medications, blood products administered, and clinical outcome data. We defined severe platelet dysfunction as less than 50 % aggregation in response to an agonist. Results: We identified 24 out of 46 children on ECMO, who had TEG®-PM performed during the study period. We found the incidence of severe bleeding was 42%, and mortality was 54% in our study cohort. In all samples measured, severe qualitative platelet dysfunction was more common for adenosine diphosphate (ADP-mediated aggregation (92% compared to arachidonic acid (AA-mediated aggregation (75%, (p=0.001. Also, ADP-mediated percent of platelet aggregation was significant lower than AA-mediated platelet aggregation (15% [IQR 2.8-48] vs 49% [IQR 22-82.5], p<0.001. There was no difference in kaolin-activated heparinase TEG® parameters between the bleeding group and the non-bleeding group. Only absolute platelet count and TEG®-PM had increased predictive value on receiver operating characteristics analyses for severe bleeding and mortality compared to ACT. Conclusions: We found frequent and severe qualitative platelet dysfunction on TEG®-PM testing in children on ECMO. Larger studies are needed to determine if the assessment of qualitative platelet function by TEG®-PM can improve prediction of bleeding complications for children on ECMO.

  14. Managing haematological disorders during pregnancy.

    Science.gov (United States)

    Koh, Mickey B C; Lao, Zhen Tang; Rhodes, Elizabeth

    2013-12-01

    The management of patients with pre-existing haematological diseases during pregnancy can be particularly challenging. The potential maternal and foetal toxicities from treatment regimens including chemotherapy for malignant haematological disorders mean that joint management between obstetricians and haematologists is essential for achieving good outcomes for both mother and baby. Patients with inherited or acquired disorders of haemostasis including platelets (essential thrombocythaemia) and coagulation (antiphospholipid syndrome) resulting in a pro-thrombotic state also require special consideration as pregnancy is generally considered to be a pro-thrombotic condition which could exacerbate the pre-existing disorder. The choice, timing and duration of anticoagulation or anti-platelet therapy require careful coordination during the antenatal, perinatal as well as postnatal periods to ensure that both maternal and foetal risks are taken into consideration. Pregnancy in women with sickle cell disease has long been identified as high risk with medical and pregnancy related risks being more common compared to women without it. A range of foetal risks have also been reported but improvement in outcomes has been seen with better obstetric and haematological care and the emphasis on multidisciplinary teamwork. The meticulous management of iron overload and risks associated with repeated blood transfusions extends into the care of pregnant women with other haemoglobinopathies like thalassemias. PMID:24060203

  15. Prophylactic platelets in dengue

    DEFF Research Database (Denmark)

    Whitehorn, James; Rodriguez Roche, Rosmari; Guzman, Maria G;

    2012-01-01

    Dengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage. As a...... result of this prophylactic platelet transfusions are sometimes advocated for the prevention of haemorrhage. There is currently no evidence to support this practice, and platelet transfusions are costly and sometimes harmful. We conducted a global survey to assess the different approaches to the use of...... platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity of...

  16. Use of 8-methoxypsoralen and long-wavelength ultraviolet radiation for decontamination of platelet concentrates

    International Nuclear Information System (INIS)

    Transmission of viral diseases through blood products remains an unsolved problem in transfusion medicine. We have developed a psoralen photochemical system for decontamination of platelet concentrates in which platelets are treated with long wavelength ultraviolet radiation (UVA, 320-400 nm) in the presence of 8-methoxypsoralen (8-MOP). Bacteria, RNA viruses, and DNA viruses ranging in genome size from 1.2 x 10(6) daltons, encompassing the size range of human pathogens, were inoculated into platelet concentrates and subjected to treatment. This system inactivated 25 to 30 logs/h of bacteria Escherichia coli or Staphylococcus aureus, 6 logs/h of bacteriophage fd, 0.9 log/h of bacteriophage R17 and 1.1 logs/h of feline leukemia virus (FeLV) in platelet concentrates maintained in standard storage bags. Platelet integrity and in vitro function before, immediately following photochemical treatment, and during prolonged storage after treatment, were evaluated by measuring: (1) extracellular pH; (2) platelet yields; (3) extracellular lactate dehydrogenase (LDH) levels; (4) platelet morphology; (5) platelet aggregation responsiveness; (6) thromboxane beta-2 (TXB-2) production; (7) dense body secretion; and (8) alpha granule secretion. These assays demonstrated that this photochemical inactivation system inactivated bacteria and viruses in platelet concentrates with minimal adverse effects on the in vitro function of platelets in comparison to untreated control concentrates maintained under current, standard blood bank conditions

  17. Role of platelet plasma membrane Ca2+-ATPase in health and disease

    Institute of Scientific and Technical Information of China (English)

    William; L; Dean

    2010-01-01

    Platelets have essential roles in both health and disease. Normal platelet function is required for hemostasis.Inhibition of platelet function in disease or by pharmacological treatment results in bleeding disorders.On the other hand,hyperactive platelets lead to heart attack and stroke.Calcium is a major second messenger in platelet activation,and elevated intracellular calcium leads to hyperactive platelets.Elevated platelet calcium has been documented in hypertension and diabetes;both conditions increase the likelihood of heart attack and stroke. Thus,proper regulation of calcium metabolism in the platelet is extremely important.Plasma membrane Ca2+-ATPase(PMCA)is a major player in platelet calcium metabolism since it provides the only significant route for calcium efflux.In keeping with the important role of calcium in platelet function,PMCA is a highly regulated transporter.In human platelets,PMCA is activated by Ca2+/calmodulin,by cAMP-dependent phosphorylation and by calpain-dependent removal of the inhibitory peptide.It is inhibited by tyrosine phosphorylation and calpain-dependent proteolysis.In addition,the cellular location of PMCA is regulated by a PDZ-domain-dependent interaction with the cytoskeleton during platelet activation.Rapid regulation by phosphorylation results in changes in the rate of platelet activation,whereas calpain-dependent proteolysis and interaction with the cytoskeleton appears to regulate later events such as clot retraction.In hypertension and diabetes,PMCA expression is upregulated while activity is decreased, presumably due to tyrosine phosphorylation.Clearly,a more complete understanding of PMCA function in human platelets could result in the identification of new ways to control platelet function in disease states.

  18. Role of Microfluidics in Blood-Brain Barrier Permeability Cell Culture Modeling: Relevance to CNS Disorders.

    Science.gov (United States)

    Rusanov, Alexander L; Luzgina, Natalia G; Barreto, George E; Aliev, Gjumrakch

    2016-01-01

    In vitro modeling of the human blood-brain barrier (BBB) is critical for pre-clinical evaluation and predicting the permeability of newly developed potentially neurotoxic and neurotrophic drugs. Here we summarize the specific structural and functional features of endothelial cells as a key component of the BBB and compare analysis of different cell culture models in reflecting these features. Particular attention is paid to cellular models of the BBB in microfluidic devices capable of circulating nutrient media to simulate the blood flow of the brain. In these conditions, it is possible to reproduce a number of factors affecting endothelial cells under physiological conditions, including shear stress. In comparison with static cell models, concentration gradients, which determine the velocity of transport of substances, reproduce more accurately conditions of nutrient medium flow, since they eliminate the accumulation of substances near the basal membrane of cells, not typical for the situation in vivo. Co-cultivation of different types of cells forming the BBB, in separate cell chambers connected by microchannels, allows to evaluate the mutual influences of cells under normal conditions and when exposed to the test substance. New experimental possibilities that can be achieved through modeling of BBB in microfluidic devices determine the feasibility of their use in the practice for pre-clinical studies of novel drugs against neurodegenerative diseases. PMID:26831260

  19. Lonomia obliqua venomous secretion induces human platelet adhesion and aggregation.

    Science.gov (United States)

    Berger, Markus; Reck, José; Terra, Renata M S; Beys da Silva, Walter O; Santi, Lucélia; Pinto, Antônio F M; Vainstein, Marilene H; Termignoni, Carlos; Guimarães, Jorge A

    2010-10-01

    The caterpillar Lonomia obliqua is a venomous animal that causes numerous accidents, especially in southern Brazil, where it is considered a public health problem. The clinical manifestations include several haemostatic disturbances that lead to a hemorrhagic syndrome. Considering that platelets play a central role in hemostasis, in this work we investigate the effects of L. obliqua venomous secretion upon blood platelets responses in vitro. Results obtained shows that L. obliqua venom directly induces aggregation and ATP secretion in human washed platelets in a dose-dependent manner. Electron microscopy studies clearly showed that the venomous bristle extract was also able to produce direct platelets shape change and adhesion as well as activation and formation of platelet aggregates. Differently from other enzyme inhibitors, the venom-induced platelet aggregation was significatively inhibited by p-bromophenacyl bromide, a specific inhibitor of phospholipases A2. Additional experiments with different pharmacological antagonists indicate that the aggregation response triggered by the venom active components occurs through a calcium-dependent mechanism involving arachidonic acid metabolite(s) of the cyclooxygenase pathway and activation of phosphodiesterase 3A, an enzyme that leads to the consumption of intracellular cAMP content. It was additionally found that L. obliqua-induced platelet aggregation was independent of ADP release. Altogether, these findings are in line with the need for a better understanding of the complex hemorrhagic syndrome resulting from the envenomation caused by L. obliqua caterpillars, and can also give new insights into the management of its clinical profile. PMID:20157842

  20. Regulating VEGF signaling in platelet concentrates via specific VEGF sequestering.

    Science.gov (United States)

    Belair, David G; Le, Ngoc Nhi; Murphy, William L

    2016-05-26

    Platelets contain an abundance of growth factors that mimic the composition of the wound healing milieu, and platelet-derived VEGF in particular can negatively influence wound healing if unregulated. Here, we sought to capture and regulate the activity of VEGF factor from human platelets using poly(ethylene glycol) microspheres. In this communication, we demonstrate that platelet freeze/thaw produced significantly higher levels of Vascular Endothelial Growth Factor (VEGF) than either calcium chloride treatment, protease activated receptor 1 activating peptide (PAR1AP) treatment, or thrombin treatment. PEG microspheres containing a VEGF-binding peptide (VBP), derived from VEGFR2, sequestered VEGF from platelet concentrate, prepared via freeze/thaw, and reduced the bioactivity of platelet concentrate in HUVEC culture, which suggests that VBP microspheres sequestered and reduced the activity of VEGF from patient-derived platelets. Here, we demonstrate the ability of VEGF sequestering microspheres to regulate the activity of VEGF derived from a growth factor-rich autologous human blood product. PMID:27010034

  1. Platelet proteomics in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Paula Vélez

    2015-06-01

    Full Text Available In recent years, platelet proteomics has been applied successfully to the study of cardiovascular diseases (CVDs. It is very well known that platelets play a pivotal role in the pathophysiological mechanisms underlying many CVDs, especially acute coronary syndromes (ACSs, since they are implied in thrombus formation after atheroma plaque rupture. This is the reason why molecules involved in platelet activation and aggregation are primary targets for treatment of ACSs. Many efforts are aimed at finding drugs that inhibit platelet activation; however it is difficult to separate the therapeutic benefits from harmful effects because pathological and physiological functions of platelets are due to the same mechanisms. Given that platelets lack a nucleus, proteomics is regarded as an ideal method to approach their biochemistry. Current platelet proteomic studies are focusing on the identification of platelet molecular and functional changes in normal and pathological states, enriching the comprehension of platelet biological function, and screening for new biomarkers and antiplatelet agents. In the present article, we introduce the reader to platelet biology and function, and revise recent advances in platelet proteomics applied to the study of CVDs, including a special emphasis on sample preparation requirements for proteome analysis of platelet clinical samples.

  2. The acute effect of methylphenidate on cerebral blood flow in boys with attention-deficit/hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Szobot, Claudia M.; Ketzer, Carla; Kapczinski, Flavio [Department of Psychiatry, Federal University of Rio Grande do Sul (Brazil); Cunha, Renato D. [Service of Nuclear Medicine, Hospital de Clinicas de Porto Alegre (Brazil); Parente, Maria A. [Department of Psychology, Federal University of Rio Grande do Sul (Brazil); Langleben, Daniel D. [Department of Psychiatry, University of Pennsylvania (United States); Acton, Paul D. [Department of Radiology, University of Pennsylvania (United States); Rohde, Luis A.P. [Department of Psychiatry, Federal University of Rio Grande do Sul (Brazil); Servico de Psiquiatria da Infancia e Adolescencia, Hospital de Clinicas de Porto Alegre (HCPA), Rua Ramiro Barcelos 2350, CEP 90035-003, RS Porto Alegre (Brazil)

    2003-03-01

    Methylphenidate (MPH) is the most commonly prescribed treatment for attention-deficit/hyperactivity disorder (ADHD). The therapeutic mechanisms of MPH are not, however, fully understood. We studied the effects of MPH on brain activity in male children and adolescents with ADHD, using the blood flow radiotracer technetium-99m ethyl cysteinate dimer ({sup 99m}Tc-ECD) and single-photon emission tomography (SPET). The study was randomized, double blind, and placebo controlled (MPH group, n=19; placebo group, n=17), Radiotracer was administered during the performance of the Continuous Performance Test and before and after 4 days of MPH treatment. Statistical parametric mapping (SPM99) analysis showed a significant reduction in regional cerebral blood flow in the left parietal region in the MPH group compared with the placebo group (P<0.05, corrected for multiple comparisons). Our findings suggest that the posterior attentional system, which includes the parietal cortex, may have a role in the mediation of the therapeutic effects of MPH in ADHD. (orig.)

  3. The acute effect of methylphenidate on cerebral blood flow in boys with attention-deficit/hyperactivity disorder

    International Nuclear Information System (INIS)

    Methylphenidate (MPH) is the most commonly prescribed treatment for attention-deficit/hyperactivity disorder (ADHD). The therapeutic mechanisms of MPH are not, however, fully understood. We studied the effects of MPH on brain activity in male children and adolescents with ADHD, using the blood flow radiotracer technetium-99m ethyl cysteinate dimer (99mTc-ECD) and single-photon emission tomography (SPET). The study was randomized, double blind, and placebo controlled (MPH group, n=19; placebo group, n=17), Radiotracer was administered during the performance of the Continuous Performance Test and before and after 4 days of MPH treatment. Statistical parametric mapping (SPM99) analysis showed a significant reduction in regional cerebral blood flow in the left parietal region in the MPH group compared with the placebo group (P<0.05, corrected for multiple comparisons). Our findings suggest that the posterior attentional system, which includes the parietal cortex, may have a role in the mediation of the therapeutic effects of MPH in ADHD. (orig.)

  4. Cardioplegia does not prevent reperfusion injury induced by intracoronary platelet deposition

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbaum, D.; Levitsky, S.; Silverman, N.; Kohler, J.; Lipowski, J.; LeBreton, G.; Feinberg, H.

    1983-09-01

    We have shown that after global myocardial ischemia, reperfusion injury may be related to platelet deposition in the coronary microcirculation. The purpose of this study was to determine whether multidose hypothermic potassium cardioplegia suppresses platelet deposition during postischemic reperfusion. Platelets labeled with /sup 111/In and erythrocytes labeled with /sup 51/Cr were injected into dogs subjected to either 120 min of continuous cardiopulmonary bypass (control, n . 4), 60 min of global normothermic myocardial ischemia followed by 50 min of reperfusion (n . 6), or global ischemia with cardioplegia (n . 5). Intracoronary platelet deposition was determined by comparing the double-labeled isotope activity of myocardial biopsy specimens to peripheral blood. Reperfusion after global myocardial ischemia resulted in substantial deposition of platelets within the coronary vasculature in both the cardioplegia-treated (215 +/- 40 platelets/mg) and untreated (269 +/- 95 platelets/mg) groups. These increases were significantly greater than those measured during continuous bypass (48 +/- 2 platelets/mg; p less than .01). Cardioplegia, despite apparent washout of the microcirculation, does not alter platelet deposition. Thus other platelet-stabilizing measures must be used to prevent platelet deposition-induced reperfusion injury after surgical global ischemia.

  5. Platelet parameters from an automated hematology analyzer in dogs with inflammatory clinical diseases.

    Science.gov (United States)

    Smith, Jo R; Smith, Katherine F; Brainard, Benjamin M

    2014-09-01

    The mean platelet component (MPC) is a proprietary algorithm of an automated laser-based hematology analyzer system which measures the refractive index of platelets. The MPC is related linearly to platelet density and is an indirect index of platelet activation status. Previous investigations of canine inflammatory conditions and models of endotoxemia demonstrated a significant decrease in the MPC, consistent with platelet activation. The purpose of this study was to evaluate the MPC and other platelet parameters in dogs with different diseases to determine if they could show differential platelet activation with different pathologies. The hypothesis was that the MPC would decrease in clinical conditions associated with systemic inflammation or platelet activation. Complete blood counts run on the analyzer from dogs with different inflammatory conditions (primary immune-mediated hemolytic anemia (IMHA) or thrombocytopenia (ITP), pituitary-dependent hyperadrenocorticism, intra-abdominal sepsis, pancreatitis, intravascular thrombus or thromboembolus and hemangiosarcoma) were reviewed retrospectively and compared with those of control dogs presenting for orthopedic evaluation. Dogs with ITP had a decreased plateletcrit and MPC, with an increased platelet volume and number of large platelets (P Dogs with IMHA had an increased plateletcrit and mass, and more numerous large platelets (P < 0.001).With the exception of the ITP group, there was no difference in MPC in the diseased groups when compared with the controls. The results of this study suggest the MPC does not change in certain canine diseases associated with systemic inflammation. PMID:25082397

  6. Antipsychotic Drugs Inhibit Platelet Aggregation via P2Y1 and P2Y12 Receptors

    Science.gov (United States)

    Wu, Chang-Chieh; Tsai, Fu-Ming; Chen, Mao-Liang; Wu, Semon; Lee, Ming-Cheng; Tsai, Tzung-Chieh; Wang, Lu-Kai; Wang, Chun-Hua

    2016-01-01

    Antipsychotic drugs (APDs) used to treat clinical psychotic syndromes cause a variety of blood dyscrasias. APDs suppress the aggregation of platelets; however, the underlying mechanism remains unknown. We first analyzed platelet aggregation and clot formation in platelets treated with APDs, risperidone, clozapine, or haloperidol, using an aggregometer and rotational thromboelastometry (ROTEM). Our data indicated that platelet aggregation was inhibited, that clot formation time was increased, and that clot firmness was decreased in platelets pretreated with APDs. We also examined the role two major adenosine diphosphate (ADP) receptors, P2Y1 and P2Y12, play in ADP-mediated platelet activation and APD-mediated suppression of platelet aggregation. Our results show that P2Y1 receptor stimulation with ADP-induced calcium influx was inhibited by APDs in human and rats' platelets, as assessed by in vitro or ex vivo approach, respectively. In contrast, APDs, risperidone and clozapine, alleviated P2Y12-mediated cAMP suppression, and the release of thromboxane A2 and arachidonic acid by activated platelets decreased after APD treatment in human and rats' platelets. Our data demonstrate that each APD tested significantly suppressed platelet aggregation via different mechanisms. PMID:27069920

  7. Reduced serum inhibition of platelet-activating factor activity in preeclampsia.

    Science.gov (United States)

    Benedetto, C; Massobrio, M; Bertini, E; Abbondanza, M; Enrieu, N; Tetta, C

    1989-01-01

    We determined in normal nonpregnant (group 1) women, normal pregnant (group 2) women, and patients with preeclampsia (group 3) the serum inhibition of platelet-activating factor activity, the presence of detectable amounts of platelet-activating factor in the blood, and platelet responsiveness in vitro to platelet-activating factor, and to other agonists (adenosine diphosphate, collagen, and ristocetin), and prostacyclin (prostaglandin I2). In patients with preeclampsia (group 3) the serum inhibition of platelet-activating factor activity was significantly lower than that in groups 1 and 2. However, no detectable amounts of platelet-activating factor were observed. The mean values of platelet aggregation induced by platelet-activating factor, adenosine diphosphate, collagen and ristocetin, and the prostaglandin I2-inhibitory concentration of 50% which is inversely correlated with platelet sensitivity to prostaglandin I2, were not significantly different between groups 2 and 3. It is suggested that in preeclampsia the defect in serum inhibitory potential of platelet-activating factor--induced platelet aggregation may contribute to the disturbance in the homeostatic balance between proaggregant and antiaggregant substances. PMID:2912073

  8. Role of newly formed platelets in thrombus formation in rat after clopidogrel treatment

    DEFF Research Database (Denmark)

    Kuijpers, Marijke J E; Megens, Remco T A; Nikookhesal, Elham; Feijge, Marion A H; De Mey, J G R; oude Egbrink, Mirjam G A; van Giezen, J J J; Heemskerk, Johan W M

    2011-01-01

    . At later time points, large thrombi formed in the clopidogrel but not in the ticagrelor group, and unprotected, juvenile platelets preferentially incorporated into the formed thrombi. However, platelets from both groups were still similarly reduced in assays of whole blood aggregation. Conclusively...... after drug cessation have not been investigated. We treated WKY rats with a single, high dose of 200 mg/kg clopidogrel or 40 mg/kg ticagrelor. Blood was collected at different time points after treatment. Flow cytometry confirmed full platelet protection against ADP-induced αIIbβ₃ activation shortly...... after clopidogrel or ticagrelor treatment. At later time points after clopidogrel treatment, a subpopulation of juvenile platelets appeared that was fully responsive to ADP. Addition of ticagrelor to clopidogrel-treated blood reduced αIIbβ₃ activation of the unprotected platelets. In contrast, at later...

  9. Reticulated platelets as a marker of platelet recovery after allogeneic stem cell transplantation.

    Science.gov (United States)

    Michur, H; Maślanka, K; Szczepiński, A; Mariańska, B

    2008-12-01

    Reticulated platelets (RP) are the youngest forms of platelets in blood and reflect the rate of bone marrow platelet production. In the present study, we used flow cytometric analysis to determine the percentage of RPs in patients undergoing allogeneic stem cell transplantation. We investigated 10 patients after transplantation from HLA identical siblings: five with acute myeloid leukemia (AML), four with chronic myeloid leukemia (CML), and one patient with myelodysplastic syndrome (MDS). Of the patients examined, four patients underwent allogeneic bone marrow transplantation and six patients underwent peripheral blood stem cell transplantation. It was observed that the initially reduced percentage of RPs (2.9 +/- 1.7%; mean +/- SD) was significantly higher (P = 0.0109) in all patients (13.6 +/- 6.4%) in the following 10-26 days. The RP percentage peak preceded the recovery of peripheral platelet count up to 45.6 x 10(9)/l on average by 3 days. We found no difference in RP% between the AML and CML patients but we did observe that in CML patients the RP percentage increased on average 7 days earlier than in AML patients. The elevated RP percentage reflects increased bone marrow regeneration and can be considered an additional marker of thrombopoietic recovery in the patients undergoing allogeneic stem cell transplantation. PMID:18983304

  10. The influence of environmental variables on platelet concentration in horse platelet-rich plasma.

    Science.gov (United States)

    Rinnovati, Riccardo; Romagnoli, Noemi; Gentilini, Fabio; Lambertini, Carlotta; Spadari, Alessandro

    2016-01-01

    Platelet-rich plasma (PRP) commonly refers to blood products which contain a higher platelet (PLT) concentration as compared to normal plasma. Autologous PRP has been shown to be safe and effective in promoting the natural processes of soft tissue healing or reconstruction in humans and horses. Variability in PLT concentration has been observed in practice between PRP preparations from different patients or from the same individual under different conditions. A change in PLT concentration could modify PRP efficacy in routine applications. The aim of this study was to test the influence of environmental, individual and agonistic variables on the PLT concentration of PRP in horses. Six healthy Standardbred mares were exposed to six different variables with a one-week washout period between variables, and PRP was subsequently obtained from each horse. The variables were time of withdrawal during the day (morning/evening), hydration status (overhydration/dehydration) treatment with anti-inflammatory drugs and training periods on a treadmill. The platelet concentration was significantly higher in horses treated with a non-steroidal anti-inflammatory drug (P = 0.03). The leukocyte concentration increased 2-9 fold with respect to whole blood in the PRP which was obtained after exposure to all the variable considered. Environmental variation in platelet concentration should be taken into consideration during PRP preparation. PMID:27377748

  11. Correlations between regional cerebral blood flow and depression scale in the mood disorder. A study using 123I-IMP SPECT

    International Nuclear Information System (INIS)

    Regional cerebral blood flow (rCBF) was assessed on 26 mood disorder patients using 123I-iodoamphetamine and single photon emission computed tomography (SPECT), and their correlations to depression scores of Hamilton's Rating Scale for Depression were studied. Region of interest (ROI) was established on coronary images and used as an indicator. As a result, left hemisphere was suspected of a primary lesion in mood disorder, however, the relationship between clinical symptoms and various lesion areas were not clarified. Further studies with neuropsychological loading or pharmaceutical loading such as antidepressant are thus expected to clarify the etiology of mood disorders. (S.Y.)

  12. Effects of platelet inhibitors on propyl gallate-induced platelet aggregation, protein tyrosine phosphorylation, and platelet factor 3 activation.

    Science.gov (United States)

    Xiao, Hongyan; Kovics, Richard; Jackson, Van; Remick, Daniel G

    2004-04-01

    Propyl gallate (PG) is a platelet agonist characterized by inducing platelet aggregation, protein tyrosine phosphorylation, and platelet factor 3 activity. The mechanisms of platelet activation following PG stimulation were examined by pre-incubating platelets with well-defined platelet inhibitors using platelet aggregation, protein tyrosine phosphorylation, activated plasma clotting time, and annexin V binding by flow cytometry. PG-induced platelet aggregation and tyrosine phosphorylation of multiple proteins were substantially abolished by aspirin, apyrase, and abciximab (c7E3), suggesting that PG is associated with activation of platelet cyclooxygenase 1, adenosine phosphate receptors, and glycoprotein IIb/IIIa, respectively. The phosphorylation of the cytoskeletal enzyme pp60(c-src) increased following PG stimulation, but was blunted by pre-incubation of platelets with aspirin, apyrase, and c7E3, suggesting that tyrosine kinase is important for the signal transduction of platelet aggregation. Propyl gallate also activates platelet factor 3 by decreasing the platelet coagulation time and increasing platelet annexin V binding. Platelet incubation with aspirin, apyrase, and c7E3 did not alter PG-induced platelet coagulation and annexin V binding. The results suggest that platelet factor 3 activation and membrane phosphotidylserine expression were not involved with activation of platelet cyclooxygenase, adenosine phosphate receptors, and glycoprotein IIb/IIIa. PG is unique in its ability to stimulate platelet aggregation and coagulation simultaneously, and platelet inhibitors in this study affect only platelet aggregation but not platelet coagulation. PMID:15060414

  13. Mechanisms of andrographolide-induced platelet apoptosis in human platelets: regulatory roles of the extrinsic apoptotic pathway.

    Science.gov (United States)

    Lien, Li-Ming; Su, Cheng-Chen; Hsu, Wen-Hsien; Lu, Wan-Jung; Chung, Chi-Li; Yen, Ting-Lin; Chiu, Hou-Chang; Sheu, Joen-Rong; Lin, Kuan-Hung

    2013-11-01

    Andrographolide, a novel nuclear factor-κB (NF-κB) inhibitor, is isolated from the leaves of Andrographis paniculata. Platelet activation is relevant to a variety of coronary heart diseases. Our recent studies revealed that andrographolide possesses potent antiplatelet activity by inhibition of the p38 MAPK/(●) HO-NF-κB-ERK2 cascade. Although platelets are anucleated cells, apoptotic machinery apparatus recently has been found to regulate platelet activation and limit platelet lifespan. Therefore, we further investigated the regulatory effects of andrographolide on platelet apoptotic events. In this study, apoptotic signaling events for caspase-3, -8, and Bid were time (10-60 min)- and dose (25-100 μΜ)-dependently activated by andrographolide in human platelets. Andrographolide could also disrupt mitrochondrial membrane potential. In addition, caspase-8 inhibitor (z-IETD-fmk, 50 μΜ) was found to reverse andrographolide-induced caspase-8 activation, whereas the antagonistic anti-Fas receptor (ZB4, 500 ng/mL) and anti-tumor necrosis factor-R1 (H398, 10 µg/mL) monoclonal antibodies did not. In conclusion, this study for the first time demonstrated that andrographolide might limit platelet lifespan by initiating the caspase-8-dependent extrinsic apoptotic pathway, in spite of no direct evidence that death receptors are involved in this process proved. Overall, the various medicinal properties of andrographolide suggest its potential value in treating patients with thromboembolic disorders. PMID:23292890

  14. Differences between the effects of EDTA and citrate anticoagulants on platelet count and mean platelet volume.

    Science.gov (United States)

    McShine, R L; Sibinga, S; Brozovic, B

    1990-01-01

    Platelet counts on whole blood samples collected into tripotassium salt of EDTA, trisodium citrate (Na3 citr), citrate phosphate dextrose adenine formula 1 (CPDA-1) and acid citrate dextrose formula A (ACD-A), all showed a statistically significant drop (P less than 0.01) after 1 h standing at room temperature (RT) as compared with the immediate (within 30 min) counts. After 1 h the enumeration became stable in the EDTA samples but the drop continued up to 4-6 h in those samples taken into citrate. The decreases in citrate were significant (18-30%, P less than 0.001). The addition of EDTA (1.5 mg/ml) to the citrated samples after the sixth hour count created a significant rise (6-22%, P less than 0.01) in the counts between the sixth and the seventh hour. Our observations show that platelet counts in citrated blood samples are lower than those in EDTA and highlight the necessity to present citrated samples mixed wtih dried EDTA when characterization or quality control of blood and blood components is required. Analysis of the mean platelet volume (MPV) showed significantly lower values (6-13%, P less than 0.05) in the citrated samples as compared to the same samples in EDTA, and a significant increase (4-6%, P less than 0.01) on the addition of EDTA to the citrated samples after the sixth hour analysis. PMID:2125542

  15. ADHD and Disruptive behavior scores – associations with MAO-A and 5-HTT genes and with platelet MAO-B activity in adolescents

    Directory of Open Access Journals (Sweden)

    Larsson Jan-Olov

    2008-04-01

    Full Text Available Abstract Background Pharmacological and genetic studies suggest the importance of the dopaminergic, serotonergic, and noradrenergic systems in the pathogenesis of Attention Deficit Hyperactivity Disorder (ADHD and Disruptive Behavior Disorder (DBD. We have, in a population-based sample, studied associations between dimensions of the ADHD/DBD phenotype and Monoamine Oxidase B (MAO-B activity in platelets and polymorphisms in two serotonergic genes: the Monoamine Oxidase A Variable Number of Tandem Repeats (MAO-A VNTR and the 5-Hydroxytryptamine Transporter gene-Linked Polymorphic Region (5-HTT LPR. Methods A population-based sample of twins, with an average age of 16 years, was assessed for ADHD/DBD with a clinical interview; Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL. Blood was drawn from 247 subjects and analyzed for platelet MAO-B activity and polymorphisms in the MAO-A and 5-HTT genes. Results We found an association in girls between low platelet MAO-B activity and symptoms of Oppositional Defiant Disorder (ODD. In girls, there was also an association between the heterozygote long/short 5-HTT LPR genotype and symptoms of conduct disorder. Furthermore the heterozygote 5-HTT LPR genotype in boys was found to be associated with symptoms of Conduct Disorder (CD. In boys, hemizygosity for the short MAO-A VNTR allele was associated with disruptive behavior. Conclusion Our study suggests that the serotonin system, in addition to the dopamine system, should be further investigated when studying genetic influences on the development of Disruptive Behavior Disorders.

  16. Acute effects of electroconvulsive therapy on regional cerebral blood flow (rCBF) in psychiatric disorders

    International Nuclear Information System (INIS)

    Electroconvulsive therapy (ECT) is frequently used in the treatment of major depression and other psychiatric disorders; its mechanism of action is not established, but previous evidence suggests that it is associated with postictal metabolic suppression. The authors have used measurements of rCBF as an index of cortical metabolic activity to study the acute effects of ECT. Measurements of rCBF were made in 32 cortical regions in 10 patients (pts) following one minute breathing of Xe-133 (5mCi/L); the measurements were performed 30min before and 50min after ECT. Bilateral ECT was administered to six pts (five diagnosed as major depressives and one schizophrenic) and unilateral ECT to four (all diagnosed as unipolar or bipolar affective disorder). The total rCBF material consists of 52 measurements in these pts, made before and after 16 bilateral and 10 unilateral treatments. ECT was found to cause significant reduction of rCBF. Mean hemispheric flows (using the Initial Slope Index to measure grey-matter flow) were reduced by about 5% in both hemispheres following bilateral treatment. Unilateral treatment caused a 9% reduction of flow in the treated hemisphere, but only 2% contralaterally. Regional patterns of flow decreases also differed between the two treatment modes: bilateral frontal reductions were found after bilateral treatment, whereas unilateral ECT caused a widespread flow reduction in the treated hemisphere, and almost no effect contralaterally. These results suggest that rCBF studies are useful for assessing ECT, and indicate that the acute cerebral effects of ECT vary with the mode of treatment

  17. Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial.

    Science.gov (United States)

    Madurantakam, Parthasarathy; Yoganarasimha, Suyog; Hasan, Fadi K

    2015-01-01

    Autologous platelet concentrates represent promising innovative tools in the field of regenerative medicine and have been extensively used in oral surgery. Unlike platelet rich plasma (PRP) that is a gel or a suspension, Leukocyte-Platelet Rich Fibrin (L-PRF) is a solid 3D fibrin membrane generated chair-side from whole blood containing no anti-coagulant. The membrane has a dense three dimensional fibrin matrix with enriched platelets and abundant growth factors. L-PRF is a popular adjunct in surgeries because of its superior handling characteristics as well as its suturability to the wound bed. The goal of the study is to demonstrate generation as well as provide detailed characterization of relevant properties of L-PRF that underlie its clinical success. PMID:26485642

  18. Increased platelet activation in early symptomatic versus asymptomatic carotid stenosis and relationship with microembolic status: Results from the Platelets And Carotid Stenosis (PACS) Study.

    LENUS (Irish Health Repository)

    Kinsella, Ja

    2013-04-26

    BACKGROUND: Cerebral microembolic signals (MES) may predict increased stroke risk in carotid stenosis. However, the relationship between platelet counts or platelet activation status and MES in symptomatic versus asymptomatic carotid stenosis has not been comprehensively assessed. SETTING: University teaching hospitals. METHODS: This prospective, pilot observational study assessed platelet counts and platelet activation status, and the relationship between platelet activation and MES in asymptomatic versus early (≤4 weeks after TIA\\/stroke) and late phase (≥3 months) symptomatic moderate or severe (≥50%) carotid stenosis patients. Full blood count measurements were performed, and whole blood flow cytometry was used to quantify platelet surface activation marker expression (CD62P and CD63) and circulating leucocyte-platelet complexes. Bilateral simultaneous transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed for 1 hour to classify patients as MES-positive or MES-negative. RESULTS: Data from 31 asymptomatic patients were compared with 46 symptomatic patients in the early phase, and 35 of these patients followed up to the late phase after symptom onset. The median platelet count (211 vs. 200 x 10(9) \\/L; p=0.03) and the median% lymphocyte-platelet complexes were higher in early symptomatic than asymptomatic patients (2.8 vs. 2.4%, p=0.001). The% lymphocyte-platelet complexes was higher in early symptomatic than asymptomatic patients with ≥70% carotid stenosis (p=0.0005), and in symptomatic patients recruited within 7 days of symptom onset (p=0.028). Complete TCD data were available in 25 asymptomatic and 31 early phase symptomatic, and 27 late phase symptomatic patients. 12% of asymptomatic versus 32% of early phase symptomatic (p=0.02) and 19% of late phase symptomatic patients (p=0.2) were MES-positive. Early symptomatic MES-negative patients had a higher% lymphocyte-platelet complexes than asymptomatic MES

  19. Development of a New Method for Platelet Function Test and Its Shearing Condition in Microfludic System

    Science.gov (United States)

    Lee, Hoyoon; Kim, Gyehyu; Choi, Seawhan; Shin, Sehyun; Korea University Department of Mechanical Engineering Team

    2015-11-01

    Platelet is a crucial blood cell on hemostasis. As platelet exposed to high shear stress, it can be activated showing morphological and functional changes to stop bleeding. When platelet is abnormal, there is high risk of cardiovascular diseases. Thus, quick and precise assay for platelet function is important in clinical treatment. In this study, we design a microfluidic system, which can test platelet function exposed with the stimulation of shear and agonists. The microfluidic system consists of three parts: 1) a shear mechanism with rotating stirrer; 2) multiple microchannels to flow samples and to stop; 3) camera-interfaced migration distance(MD) analyzing system. When sheared blood is driven by pressure through the microchannel, shear-activated platelets adhere to a collagen-coated surface, causing blood flow to significantly slow and eventually stop. As the micro-stirrer speed increases, MD decreases exponentially at first, but it increases beyond a critical rpm after all. These results are coincident with data measured by FACS flowcytometry. These results imply that the present system could quantitatively measure the degree of activation, aggregation and adhesion of platelets and that blood MD is potent index for measuring the shear-dependence of platelet function.

  20. Roles of thrombin and platelet membrane glycoprotein IIb/IIIa in platelet-subendothelial deposition after angioplasty in an ex vivo whole artery model

    International Nuclear Information System (INIS)

    Platelet deposition at the site of injury caused by balloon angioplasty is associated with acute closure and restenosis. In a new ex vivo whole artery angioplasty model, the authors examined the roles of thrombin inhibition with D-Phe-Pro-ArgCH2Cl (PPACK) and inhibition of the platelet membrane fibrinogen receptor glycoprotein IIb/IIIa (GPIIb/IIIa) with monoclonal antibody 7E3 on platelet deposition at the site of balloon injury. Fresh rabbit aortas were mounted in a perfusion chamber. One half of the mounted arterial segment was dilated with a standard angioplasty balloon catheter and the uninjured half served as the control segment. The vessels were perfused with human blood at physiological pressure and shear rates of 180-250 second-1 for 30 minutes. Platelet deposition was measured using 111In-labeled platelets and scanning electron microscopy. With heparin (2 units/ml) anticoagulation, 8.2 ± 2.2 x 10(6) platelets/cm2 were deposited at the site of balloon injury compared with 0.7 ± 0.2 x 10(6) platelets/cm2 on uninjured segments (p less than 0.02, n = 7). PPACK was tested at a concentration (10 microM) that totally inhibited platelet aggregation in response to thrombin. 7E3 was tested at a concentration (10 micrograms/ml) that totally inhibited platelet aggregation. Platelet deposition at the site of balloon injury was reduced 47% by PPACK and 70% by 7E3 compared with heparin. At shear rates seen in nonstenotic coronary arteries, PPACK and 7E3 are more effective than heparin in reducing platelet deposition at the site of balloon injury. The significant inhibition of platelet deposition by PPACK demonstrates the importance of heparin-resistant thrombin in platelet thrombus formation

  1. Platelet gel for healing cutaneous chronic wounds.

    Science.gov (United States)

    Crovetti, Giovanni; Martinelli, Giovanna; Issi, Marwan; Barone, Marilde; Guizzardi, Marco; Campanati, Barbara; Moroni, Marco; Carabelli, Angelo

    2004-04-01

    Wound healing is a specific host immune response for restoration of tissue integrity. Experimental studies demonstrated an alteration of growth factors activity due to their reduced synthesis, increased degradation and inactivation. In wound healing platelets play an essential role since they are rich of alpha-granules growth factors (platelet derived growth factor--PDGF; transforming growth factor-beta--TGF-beta; vascular endothelial growth factor--VEGF). Topical use of platelet gel (PG), hemocomponent obtained from mix of activated platelets and cryoprecipitate, gives the exogenous and in situ adding of growth factors (GF). The hemocomponents are of autologous or homologous origin. We performed a technique based on: multicomponent apheretic procedure to obtain plasma rich platelet and cryoprecipitate; manual processing in an open system, in sterile environment, for gel activation. Every step of the gel synthesis was checked by a quality control programme. The therapeutic protocol consists of the once-weekly application of PG. Progressive reduction of the wound size, granulation tissue forming, wound bed detersion, regression and absence of infective processes were considered for evaluating clinical response to hemotherapy. 24 patients were enrolled. They had single or multiple cutaneous ulcers with different ethiopathogenesis. Only 3 patients could perform autologous withdrawal; in the others homologous hemocomponent were used, always considering suitability and traceability criteria for transfusional use of blood. Complete response was observed in 9 patients, 2 were subjected to cutaneous graft, 4 stopped treatment, 9 had partial response and are still receiving the treatment. In each case granulation tissue forming increased following to the first PG applications, while complete re-epithelization was obtained later. Pain was reduced in every treated patient. Topical haemotherapy with PG may be considered as an adjuvant treatment of a multidisciplinary process

  2. Exposure to acrolein by inhalation causes platelet activation

    International Nuclear Information System (INIS)

    Acrolein is a common air pollutant that is present in high concentrations in wood, cotton, and tobacco smoke, automobile exhaust and industrial waste and emissions. Exposure to acrolein containing environmental pollutants such as tobacco smoke and automobile exhaust has been linked to the activation of the coagulation and hemostasis pathways and thereby to the predisposition of thrombotic events in human. To examine the effects of acrolein on platelets, adult male C57Bl/6 mice were subjected acute (5 ppm for 6 h) or sub-chronic (1 ppm, 6 h/day for 4 days) acrolein inhalation exposures. The acute exposure to acrolein did not cause pulmonary inflammation and oxidative stress, dyslipidemia or induce liver damage or muscle injury. Platelet GSH levels in acrolein-exposed mice were comparable to controls, but acrolein-exposure increased the abundance of protein-acrolein adducts in platelets. Platelets isolated from mice, exposed to both acute and sub-chronic acrolein levels, showed increased ADP-induced platelet aggregation. Exposure to acrolein also led to an increase in the indices of platelet activation such as the formation of platelet-leukocyte aggregates in the blood, plasma PF4 levels, and increased platelet-fibrinogen binding. The bleeding time was decreased in acrolein exposed mice. Plasma levels of PF4 were also increased in mice exposed to environmental tobacco smoke. Similar to inhalation exposure, acrolein feeding to mice also increased platelet activation and established a pro-thrombotic state in mice. Together, our data suggest that acrolein is an important contributing factor to the pro-thrombotic risk in human exposure to pollutants such as tobacco smoke or automobile exhaust, or through dietary consumption.

  3. Adhesion of human platelets to serum amyloid A.

    Science.gov (United States)

    Urieli-Shoval, Simcha; Shubinsky, George; Linke, Reinhold P; Fridkin, Mati; Tabi, Israel; Matzner, Yaacov

    2002-02-15

    Serum amyloid A (SAA) is an acute phase reactant, and its level in the blood is elevated to 1000-fold in response of the body to trauma, infection, inflammation, and neoplasia. SAA was reported to inhibit platelet aggregation and to induce adhesion of leukocytes. This study looked at adhesion of human platelets to SAA. Immobilized SAA supported the adhesion of human washed platelets; level of adhesion to SAA was comparable to fibronectin and lower than to fibrinogen. Adhesion to SAA was further enhanced by Mn(2+) and the physiological agonist, thrombin. Platelet adhesion to SAA was completely abolished by anti-SAA antibody. SAA-induced adhesion was inhibited by antibodies against the integrin receptor alphaIIbbeta3, by the peptide GRGDSP and by SAA-derived peptide containing YIGSR-like and RGD-like adhesion motifs (amino acids 29 to 42). Adhesion was not inhibited by control immunoglobulin G, by antibody against the integrin receptor alphaVbeta3, by the peptide GRGESP, and by SAA-derived peptide that includes incomplete RGD motif. SAA-derived peptide 29 to 42 also inhibited platelet adhesion to fibronectin. Transfected human melanoma cells expressing alphaIIbbeta3 adhered to SAA, whereas transfected cells expressing alphaVbeta3 did not. By using flow cytometry, the alphaIIbbeta3 cells displayed significantly higher levels of binding of soluble SAA than the alphaVbeta3 cells. These data indicate that human platelets specifically adhere to SAA in an RGD- and alphaIIbbeta3-dependent manner. Thus, SAA may play a role in modulating platelet adhesion at vascular injury sites by sharing platelet receptors with other platelet-adhesive proteins. PMID:11830469

  4. Single-photon tomographic determination of regional cerebral blood flow in psychiatric disorders

    International Nuclear Information System (INIS)

    Regional cerebral blood flow (rCBF) was measured by single-photon emission computed tomography (SPECT) of 133-Xe washout in 29 normal volunteers, 22 unipolar endogenous depressives (UPE), 9 unipolar nonendogenous depressives (UPNE), 13 bipolar depressed patients (BPD), and 14 schizophrenic patients (SCHZ). RCBF was measured 2 and 6 cm above and parallel to the cantho-meatal line and quantitated in 14 gray matter regions. Most subjects were drug-free for 4-14 days. Diagnoses were made by experienced clinicians employing the Research Diagnostic Criteria, the Hamilton Rating Scale, and the dexamethasone suppression test. SCHZ were rated with the Brief Psychiatric Rating Scale. UPE had reduced flow compared to normals in the right parietal and temporal lobes and a nonsignificant trend toward left temporal flow reductions. UPNE were not different from normal or other patient groups. BPD had significant flow elevations in the left hemisphere relative to normal, and in both hemispheres relative to UPE. SCHZ were not significantly different from normal or other patient groups. Anterior-posterior flow shifts were evaluated by subtracting parietal or temporal flows from frontal flows. SCHZ demonstrated a greater posterior shift (lower relative frontal lobe flow) in comparison to both UPE and UPNE. The most significant regional flow abnormalities were observed as frontal flow reductions in individual SCHZ, although these were not significant in the whole group in comparison to normal

  5. 血小板microRNAs在先天性心脏病患儿中输血导致的血小板激活作用研究%Impact of packed red blood cell transfusion on platelet activation and aggrega-tion in pediatric patients with cardiac disease

    Institute of Scientific and Technical Information of China (English)

    苗晓蕾; 王旭; 刘晋萍; 崔勇丽; 赵明霞; 冯正义; 赵举; 龙村; 李守军; 晏馥霞

    2015-01-01

    Objective The aim of this study is to observe the impact of packed RBC transfusion on platelet activation and ag⁃gregation in vitro in pediatric patients with cardiac disease and to clarity whether circulating platelet microRNAs could be serve as a new indicator of platelet activation. Methods One hundred infant patients were randomly divided into 2 groups, transfusion group and non-transfusion group. Each group has 50 patients. In vitro transfusions were performed by the addition of RBC obtained from transfusion packs into fresh whole blood with a ratio about 1:4 (0.5 ml of RBC mixed with 1.8 ml of whole blood). After 30 min, the expression of P-selectin and the content of platelet microparticle (PMP) were tested by flow cytometry. Light transmission aggregometry was per⁃formed to determine the platelet aggregation. The expression levels of four kinds of circulation platelet microRNAs were detected by Taq⁃man quantitative real-time PCR. Results There were no significant difference in the baseline hemoglobin level between the two groups ( P>0. 05 ) . After RBC transfusion, the Hb level was elevated by 23 ± 6 g/L. Compared with non-transfusion group, platelet aggregation in transfusion group was significantly increased( P<0.05).Platelet activation was also increased by transfusion as confirmed by the elevation of P-selectin and PMP expressions induced by 20μM ADP. Similar results were found with the four kinds of circulat⁃ing platelet microRNAs ( P<0.05) . In the non-transfusion group, the levels of four kinds of microRNAs in the cyanotic subgroup were significantly elevated than the acyanotic subgroup( P<0.05) . Conclusion RBC transfusion increases in vitro platelet activation in pe⁃diatric patients with cardiac disease, providing a possible explanation for the increase in recurrent ischemic event and mortality reported after RBC transfusion in clinical practice. Circulation platelet microRNAs may serve as a new marker of platelet activation.%目的:

  6. Can mean platelet component be used as an index of platelet activity in stable coronary artery disease?

    LENUS (Irish Health Repository)

    Cooke, John

    2012-01-31

    Acute coronary syndrome is associated with intracoronary thrombosis secondary to platelet activation. Previous groups have investigated platelet activation in both stable and unstable vascular disease. Most measures of platelet activation are not routinely available or easily adaptable to large scale clinical use. Recently, measurement of the mean platelet component (MPC) has become part of the routine data provided by an automated full blood count analyser, the Advia 120. MPC measures platelet density which changes on platelet activation. Our objectives were to determine if platelet activation, as measured by MPC, is increased in patients with stable coronary artery disease (CAD) and to determine if MPC could be useful in differentiating people with stable CAD from controls on an everyday clinical basis. Three hundred and forty-five consecutive patients attending for elective coronary angiography had full blood count analysis and MPC measurement performed using an ADVIA-120 analyser. Three hundred and twenty-four were analysed in our final dataset. Two hundred and fifty-three (78%) had CAD. Patients with CAD were significantly (p<0.001) older than those without (63.8 versus 56.0 years). Results failed to demonstrate a difference (p=0.467) in MPC between patients with CAD and those with normal coronary arteries (25.8 versus 26.0). Likewise, there was no correlation between MPC and the severity of CAD (Kendall\\'s tau b=-0.086, p=0.04). MPC is not a useful index of platelet activity in stable CAD when used in everyday clinical practice.

  7. Can mean platelet component be used as an index of platelet activity in stable coronary artery disease?

    LENUS (Irish Health Repository)

    Cooke, John

    2009-04-01

    Acute coronary syndrome is associated with intracoronary thrombosis secondary to platelet activation. Previous groups have investigated platelet activation in both stable and unstable vascular disease. Most measures of platelet activation are not routinely available or easily adaptable to large scale clinical use. Recently, measurement of the mean platelet component (MPC) has become part of the routine data provided by an automated full blood count analyser, the Advia 120. MPC measures platelet density which changes on platelet activation. Our objectives were to determine if platelet activation, as measured by MPC, is increased in patients with stable coronary artery disease (CAD) and to determine if MPC could be useful in differentiating people with stable CAD from controls on an everyday clinical basis. Three hundred and forty-five consecutive patients attending for elective coronary angiography had full blood count analysis and MPC measurement performed using an ADVIA-120 analyser. Three hundred and twenty-four were analysed in our final dataset. Two hundred and fifty-three (78%) had CAD. Patients with CAD were significantly (p<0.001) older than those without (63.8 versus 56.0 years). Results failed to demonstrate a difference (p=0.467) in MPC between patients with CAD and those with normal coronary arteries (25.8 versus 26.0). Likewise, there was no correlation between MPC and the severity of CAD (Kendall\\'s tau b=-0.086, p=0.04). MPC is not a useful index of platelet activity in stable CAD when used in everyday clinical practice.

  8. Concentration of platelets and growth factors in platelet-rich plasma from Goettingen minipigs

    Directory of Open Access Journals (Sweden)

    Jungbluth, Pascal

    2014-11-01

    Full Text Available In minipigs little is known about the concentration of growth factors in plasma, despite their major role in several patho-physiological processes such as healing of fractures. This prompted us to study the concentration of platelets and selected growth factors in plasma and platelet-rich plasma (PRP preparation of sixteen Goettingen minipigs. Platelet concentrations increased significantly in PRP in comparison to native blood plasma. Generally, significant increase in the concentration of all growth factors tested was observed in the PRP in comparison to the corresponding plasma or serum. Five of the plasma samples examined contained detectable levels of bone morphogenic protein 2 (BMP-2 whereas eleven of the plasma or serum samples contained minimal amounts of vascular endothelial growth factor (VEGF and platelet-derived growth factor (PDGF-bb respectively. On the other hand variable concentrations of bone morphogenic protein 7 (BMP-7 and transforming growth factor β1 (TGF-β1 were measured in all plasma samples. In contrast, all PRP samples contained significantly increased amounts of growth factors. The level of BMP-2, BMP-7, TGF-β1, VEGF and PDGF-bb increased by 17.6, 1.5, 7.1, 7.2 and 103.3 fold, in comparison to the corresponding non-enriched preparations. Moreover significant positive correlations were found between platelet count and the concentrations of BMP-2 (r=0.62, p<0.001, TGF-β1 (r=0.85, p<0.001, VEGF (r=0.46, p<0.01 and PDGF-bb (r=0.9, p<0.001. Our results demonstrate that selected growth factors are present in the platelet-rich plasma of minipigs which might thus serve as a source of autologous growth factors.

  9. Disorder of blood-aqueous barrier following Ahmed Glaucoma Valve implantation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Min-wen; WANG Wei; CHEN Shi-da; HUANG Wen-bin; ZHANG Xiu-lan

    2013-01-01

    Background Ahmed Glaucoma Valve implantation (AGVI) is used to treat refractory glaucoma.Breakdown of the blood-aqueous barrier (BAB) has been noted after some surgical techniques.The current study was designed to assess BAB disruption after AGVI.Methods Anterior chamber protein content was measured by the laser flare cell photometry in 22 eyes of 22 patients with refractory glaucoma before AGVI and at each postoperative visit up to 1 month.Results Before AGVI the mean aqueous flare values in all eyes were (15.17±9.84) photon counts/ms.After AGVI,the values significantly increased at day 1,day 3,and week 1 compared to those before AGVI (all P <0.05) with a peak at day 3.They returned to pre-operative levels at week 2,and were lower than preoperative level at month 1.Eyes with previous intraocular surgery history had greater aqueous flare values than those without previous intraocular surgery history,but there were no significant differences at all time points postoperatively (all P >0.05).Furthermore,eyes with shallow anterior chambers had greater aqueous flare values at day 3 and week 1 (all P <0.05).When comparing eyes with other refractory glaucoma conditions,neovascular glaucoma combined with intravitreal bevacizumab injection resulted in lower aqueous flare values after AGVI,but no significant differences were observed at all time points,postoperatively (all P>0.05).Conclusions The BAB was impaired and inflammation was present in the anterior chamber in refractory glaucomatous eyes following AGVI.However,such conditions were resolved within 1 month postoperatively.Intravitreal bevacizumab treatment in neovascular glaucoma eyes before AGVI may prevent BAB breakdown.

  10. Calpain Activity and Toll-Like Receptor 4 Expression in Platelet Regulate Haemostatic Situation in Patients Undergoing Cardiac Surgery and Coagulation in Mice

    Directory of Open Access Journals (Sweden)

    Jui-Chi Tsai

    2014-01-01

    Full Text Available Human platelets express Toll-like receptors (TLR 4. However, the mechanism by which TLR4 directly affects platelet aggregation and blood coagulation remains to be explored. Therefore, in this study, we evaluated the platelet TLR4 expression in patients who underwent CABG surgery; we explored the correlation between platelet TLR4 expression and the early outcomes in hospital of patients. Additionally, C57BL/6 and C57BL/6-TlrLPS−/− mice were used to explore the roles of platelet TLR4 in coagulation by platelet aggregometry and rotation thromboelastometry. In conclusion, our results highlight the important roles of TLR4 in blood coagulation and platelet function. Of clinical relevance, we also explored novel roles for platelet TLR4 that are associated with early outcomes in cardiac surgery.

  11. Accuracy of Platelet Counting by Optical and Impedance Methods in Patients with Thrombocytopaenia and Microcytosis

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    Mohamed-Rachid Boulassel

    2015-11-01

    Full Text Available Objectives: Obtaining accurate platelet counts in microcytic blood samples is challenging, even with the most reliable automated haematology analysers. The CELL-DYN™ Sapphire (Abbott Laboratories, Chicago, Illinois, USA analyser uses both optical density and electronic impedance methods for platelet counting. This study aimed to evaluate the accuracy of optical density and electrical impedance methods in determining true platelet counts in thrombocytopaenic samples with microcytosis as defined by low mean corpuscular volume (MCV of red blood cells. Additionally, the impact of microcytosis on platelet count accuracy was evaluated. Methods: This study was carried out between February and December 2014 at the Haematology Laboratory of the Sultan Qaboos University Hospital in Muscat, Oman. Blood samples were collected and analysed from 189 patients with thrombocytopaenia and MCV values of <76 femtolitres. Platelet counts were tested using both optical and impedance methods. Stained peripheral blood films for each sample were then reviewed as a reference method to confirm platelet counts. Results: The platelet counts estimated by the impedance method were on average 30% higher than those estimated by the optical method (P <0.001. The estimated intraclass correlation coefficient was 0.52 (95% confidence interval: 0.41–0.62, indicating moderate reliability between the methods. The degree of agreement between methods ranged from -85.5 to 24.3 with an estimated bias of -30, suggesting that these methods generate different platelet results. Conclusion: The impedance method significantly overestimated platelet counts in microcytic and thrombocytopaenic blood samples. Further attention is therefore needed to improve the accuracy of platelet counts, particularly for patients with conditions associated with microcytosis.

  12. The nature of interactions between tissue-type plasminogen activator and platelets

    International Nuclear Information System (INIS)

    To elucidate interactions responsible for inhibition of aggregation of platelets in platelet-rich plasma (PRP) harvested from whole blood preincubated with t-PA, experiments were performed with PRP and washed platelets under diverse conditions of preincubation. Both ADP and collagen induced aggregation were inhibited in PRP unless aprotinin had been added to the preincubated whole blood concomitantly with t-PA. However, in washed platelets prepared after the same exposure aggregation was intact. When washed platelets were supplemented with fibrinogen degradation products (FDPs) in concentrations simulating those in whole blood preincubated with t-PA, aggregation induced with either ADP or collagen was inhibited. Thus, the inhibition in PRP depended on generation of FDPs by activated plasminogen. The functional integrity of surface glycoprotein (GP) IIb/IIIa receptors in washed platelets was documented by autoradiography after SDS-PAGE of surface labeled GPs and by fibrinogen binding despite preincubation of the whole blood or washed platelets themselves with t-PA and plasminogen as long as exogenous calcium (greater than or equal to 0.1 microM) was present. In contrast, when calcium was absent, the platelet GP IIb/IIIa receptor was rendered susceptible to degradation by plasmin, and aggregation was inhibited by preincubation at 37 degrees C even if aprotinin was present when aggregation was being assayed. These observations reconcile disparate results in the literature from studies in vivo and in vitro by demonstrating that inhibition of aggregation of platelets in PRP and in whole blood reflects indirect effects of plasminogen activation rather than direct effects of t-PA or plasmin on the platelets themselves

  13. Prevalence of Sexually Transmitted Diseases and Blood-Borne Transmitted Infections among Male Patients with Antisocial Personality Disorder

    Directory of Open Access Journals (Sweden)

    Hamza Yıldız

    2015-03-01

    Full Text Available Objective: The aim of this study was to compare the patients who have antisocial personality disorder (ASPD and the healthy individuals in terms of sexually transmitted diseases (STDs and Blood-Borne Transmitted Infections (BTIs prevalences. Methods: This study is a prospective, single-center, open-label, non-randomized controlled clinical study. There were two groups in the study. The patient group consistsed of 100 males who were diagnosed as ASPD with a clinical interview form. The control group consisted of 98 healthy males who did not have any psychiatric disorder. Dermatologic examination was performed, and clinical findings were recorded. Results: The mean age of the patient group was 21.96±2.40 (range 20-37 years. The mean age of the control group was 24.20±2.88 (21-36 years. The most common disease was gonorrhea (25% followed by genital wart (11%, molluskum contagiosum (5%, HBsAg (4%, and HSV-2 seropositivity (4% in the patients group. In the control group, HSV-2 seropositivity (4.08%, genital wart (3.06%, molluskum contagiosum (3.06%, and gonorrhe (1.02% were commonly seen in the control group. STDs and/or BVTIs were found more common in the patients group (82% than that in the control group (45.91% (X2=30.62, p=0.000. Conclusions: The patients with ASPD are at greater risk than normal population to catch a STDs or BTIs because of their lower educational levels and riskier behaviors. This condition entertains a risk in the general population and the patients themselves.

  14. Changes in cerebral blood flow after cognitive behavior therapy in patients with panic disorder: a SPECT study

    Directory of Open Access Journals (Sweden)

    Seo HJ

    2014-04-01

    Full Text Available Ho-Jun Seo,1 Young Hee Choi,2 Yong-An Chung,3 Wangku Rho,1 Jeong-Ho Chae11Department of Psychiatry, College of Medicine, The Catholic University of Korea, Seoul, South Korea; 2Metta Institute of Cognitive Behavior Therapy, Seoul, South Korea; 3Department of Radiology, Nuclear Medicine, College of Medicine, The Catholic University of Korea, Seoul, South KoreaAim: Inconsistent results continue to be reported in studies that examine the neural correlates of cognitive behavioral therapy (CBT in patients with panic disorder. We examined the changes in regional cerebral blood flow (rCBF associated with the alleviation of anxiety by CBT in panic patients.Methods: The change in rCBF and clinical symptoms before and after CBT were assessed using single photon emission computed tomography and various clinical measures were analyzed.Results: Fourteen subjects who completed CBT showed significant improvements in symptoms on clinical measures, including the Panic and Agoraphobic Scale and the Anxiety Sensitivity Index-Revised. After CBT, increased rCBF was detected in the left postcentral gyrus (BA 43, left precentral gyrus (BA 4, and left inferior frontal gyrus (BA 9 and BA 47, whereas decreased rCBF was detected in the left pons. Correlation analysis of the association between the changes in rCBF and changes in each clinical measure did not show significant results.Conclusion: We found changes in the rCBF associated with the successful completion of CBT. The present findings may help clarify the effects of CBT on changes in brain activity in panic disorder.Keyword: single photon emission computed tomography (SPECT, anxiety, neural correlate, brain activity

  15. Attention deficit/hyperactivity disorder: is there a correlation between dopamine transporter density and cerebral blood flow?

    Science.gov (United States)

    da Silva, Neivo; Szobot, Claudia M; Anselmi, Carlos E; Jackowski, Andrea P; Chi, Shih M; Hoexter, Marcelo Q; Anselmi, Osvaldo E; Pechansky, Flavio; Bressan, Rodrigo A; Rohde, Luis A

    2011-08-01

    Attention deficit/hyperactivity disorder (ADHD) is one of the most frequent behavioral problems in school-age children. Although the etiology remains unclear, the involvement of the dopaminergic system has been suggested by genetic studies that report an overexpression of the dopamine transporter (DAT) gene. In spite of these abnormalities being directly related to the decrease of dopamine (DA) in the striatum (STR), abnormalities in brain perfusion have also been observed in cortical-subcortical structures. Functional neuroimaging studies have suggested that the DA concentration may cause changes in the cerebral blood flow (CBF). The objective of our study was to evaluate the relationship between DAT density in STR and cortical-subcortical impairment in CBF. Based on the hypothesis that there is a correlation between DA availability and brain perfusion, we postulated that individuals with ADHD, with a higher DAT density in the basal ganglia, will have lower perfusion in the fronto-striatal-cerebellar networks. We used Tc-99m TRODAT-1 SPECT to measure DAT density and Tc-99m ECD SPECT to assess brain perfusion. Ten adolescents diagnosed with ADHD by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria were investigated. Analysis with Statistical Parametric Mapping 5 corrected for multiple comparisons, using small volume correction, showed a significant negative correlation between the DAT density in the STR and CBF in the cingulate gyrus, frontal lobe, temporal lobe, and cerebellum (pFDR <0.01). Our findings suggest that higher DAT density in the STR was associated with a decrease in the regional CBF in the cortical and subcortical attention network. PMID:21716015

  16. A physical description of the adhesion and aggregation of platelets

    CERN Document Server

    Chopard, Bastien; Latt, Jonas; Dubois, Frank; Yourassowsky, Catherine; Van Antwerpen, Pierre; Eker, Omer; Vanhamme, Luc; Perez-Morga, David; Courbebaisse, Guy; Boudjeltia, Karim Zouaoui

    2015-01-01

    The early stages of clot formation in blood vessels involve platelets adhesion-aggregation. Although these mechanisms have been extensively studied, gaps in their understanding still persist. We have performed detailed in-vitro experiments and developed a numerical model to better describe and understand this phenomenon. Unlike previous studies, we took into account both activated and non-activated platelets, as well as the 3D nature of the aggregation process. Our investigation reveals that blood albumin is a major parameter limiting platelet adhesion and aggregation. Our results also show that the well accepted Zydney-Colton shear-induced diffusivity is much too low to explain the observed deposition rate. Simulations are in very good agreement with observations and provide quantitative estimates of the adhesion and aggregation rates that are hard to measure experimentally.

  17. Motor-driven marginal band coiling promotes cell shape change during platelet activation.

    Science.gov (United States)

    Diagouraga, Boubou; Grichine, Alexei; Fertin, Arnold; Wang, Jin; Khochbin, Saadi; Sadoul, Karin

    2014-01-20

    Platelets float in the blood as discoid particles. Their shape is maintained by microtubules organized in a ring structure, the so-called marginal band (MB), in the periphery of resting platelets. Platelets are activated after vessel injury and undergo a major shape change known as disc to sphere transition. It has been suggested that actomyosin tension induces the contraction of the MB to a smaller ring. In this paper, we show that antagonistic microtubule motors keep the MB in its resting state. During platelet activation, dynein slides microtubules apart, leading to MB extension rather than contraction. The MB then starts to coil, thereby inducing the spherical shape of activating platelets. Newly polymerizing microtubules within the coiled MB will then take a new path to form the smaller microtubule ring, in concerted action with actomyosin tension. These results present a new view of the platelet activation mechanism and reveal principal mechanistic features underlying cellular shape changes. PMID:24421335

  18. Platelet activation, function, and reactivity in atherosclerotic carotid artery stenosis: a systematic review of the literature.

    LENUS (Irish Health Repository)

    Kinsella, J A

    2012-09-27

    An important proportion of transient ischemic attack or ischemic stroke is attributable to moderate or severe (50-99%) atherosclerotic carotid stenosis or occlusion. Platelet biomarkers have the potential to improve our understanding of the pathogenesis of vascular events in this patient population. A detailed systematic review was performed to collate all available data on ex vivo platelet activation and platelet function\\/reactivity in patients with carotid stenosis. Two hundred thirteen potentially relevant articles were initially identified; 26 manuscripts met criteria for inclusion in this systematic review. There was no consistent evidence of clinically informative data from urinary or soluble blood markers of platelet activation in patients with symptomatic moderate or severe carotid stenosis who might be considered suitable for carotid intervention. Data from flow cytometry studies revealed evidence of excessive platelet activation in patients in the early, sub-acute, or late phases after transient ischemic attack or stroke in association with moderate or severe carotid stenosis and in asymptomatic moderate or severe carotid stenosis compared with controls. Furthermore, pilot data suggest that platelet activation may be increased in recently symptomatic than in asymptomatic severe carotid stenosis. Excessive platelet activation and platelet hyperreactivity may play a role in the pathogenesis of first or subsequent transient ischemic attack or stroke in patients with moderate or severe carotid stenosis. Larger longitudinal studies assessing platelet activation status with flow cytometry and platelet function\\/reactivity in symptomatic vs. asymptomatic carotid stenosis are warranted to improve our understanding of the mechanisms responsible for transient ischemic attack or stroke.

  19. Anti-Platelet Activities of Polyozellin In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Eun-Ju Yang

    2015-09-01

    Full Text Available Purpose: Thrombosis and thromboembolic occlusions of blood vessels are a major complication in various peripheral vascular diseases. The agents for the inhibition of platelet function are recognized as key tools in the treatment of atherothrombosis. Therefore, it became a mainstay medication for a wide range of vascular diseases. Polyozellin (POZ, a major constituent of an edible mushroom Polyozellus multiplex, was reported to have anti-oxidant, anti-angiogenesis, anti-cancer, and anti-inflammatory effects. However, anti-platelet effect of POZ has not been investigated yet. Methods: In our study, the anti-platelet activities of POZ were measured by thrombin- or collagen-induced platelet aggregation in vitro, adenosine diphosphate (ADP-induced platelet aggregation in vivo, and the thrombus formation in vivo. Results: POZ effectively inhibited the platelet aggregation not only in vitro using freshly isolated human platelets, but also in vivo thrombin or collagen-induced platelet aggregation. In accordance with the anti-platelet activities in vitro, POZ enhanced anti-thrombotic effect in vivo pulmonary embolism model and arterial thrombosis model. Conclusion: These results indicate that POZ possesses anti-platelet activities and might be useful for developing the drug candidates or functional foods for treatment of cardiovascular diseases without side effects.

  20. Loss of fibrinogen receptors from the platelet surface during simulated extracorporeal circulation

    International Nuclear Information System (INIS)

    In vitro recirculation of fresh human heparinized blood in an extracorporeal circuit with a membrane oxygenator decreased fibrinogen- induced platelet aggregation and diminished the number of fibrinogen receptors and glycoprotein IIb/IIIa (GPIIb/GPIIIa) antigenic sites on the platelet surface. In seven experiments, the mean +/- SD Km value for fibrinogen (i.e., molar concentration of fibrinogen required to cause 50% of the maximal rate of aggregation) was 1.58 x 10(-7) mol/L +/- 0.68 x 10(-7) mol/L. After recirculation, this value increased to 3.8 x 10(-7) mol/L +/- 1.94 x 10(-7) mol/L. The maximal aggregation rate of chymotrypsin-treated platelets decreased by 40% after 2 hours of recirculation. The number of fibrinogen receptors on platelets, which were treated with chymotrypsin after a recirculation, decreased from 41,370 +/- 24,000 to 13,230 +/- 10,230/platelet under the same conditions. The number of antigenic sites for monoclonal antibody reacting with GPIIb/GPIIIa complex of adenosine diphosphate-stimulated platelets decreased from 34,200 +/- 5,940 to 19,500 +/- 9,680/platelet after recirculation. Prostaglandin E1 (0. 3 mumol/L) in the perfusion circuit preserved the ability of platelets to react with fibrinogen. In conclusion, the loss of fibrinogen receptors from the surface of platelet membranes results from the interaction of platelets with the surfaces of perfusion circuits

  1. Characteristics of an autologous leukocyte and platelet-rich fibrin patch intended for the treatment of recalcitrant wounds

    DEFF Research Database (Denmark)

    Lundquist, Rasmus; Holmstrøm, Kim; Clausen, Christian;

    2012-01-01

    , antibody arrays, and cell culture assays, we show that the patch is a three-layered membrane comprising a fibrin sheet, a layer of platelets, and a layer of leukocytes. Mean recovery of platelets from the donated blood was 98% (±95%CI 0.8%). Mean levels of platelet-derived growth factor AB, human......We have investigated the physical, biochemical, and cellular properties of an autologous leukocyte and platelet-rich fibrin patch. This was generated in an automated device from a sample of a patient's blood at the point of care. Using microscopy, cell counting, enzyme-linked immunosorbent assay...

  2. Estudo farmacognóstico e atividade in vitro sobre a coagulação sanguínea e agregação plaquetária das folhas de Passiflora nitida Kunth (Passifloraceae Pharmacognostic study and in vitro activity on blood coagulation and platelet aggregation of leaves of Passiflora nitida Kunth (Passifloraceae

    Directory of Open Access Journals (Sweden)

    Maria José de Carvalho

    2010-03-01

    fruits of this species by the local population for gastrointestinal disorders. Considering the pharmacological potential of the genus, this work aimed to carry out study of phytochemical characterization of this species and study the effects of the aqueous (AE, ethanol (EE and hexane (HE extracts from its leaves on blood coagulation and platelet aggregation. Thin-layer chromatography and nuclear magnetic resonance were carried out for the phytochemical characterization. The effect of the extracts on the coagulation was evaluated by prothrombin time (PT and activated partial thromboplastin time (aPTT tests. The effect on the platelet aggregation was evaluated in platelet-rich plasma by spectrophotometric method, using adenosine diphosphate (ADP and adrenaline (ADR as inducers of aggregation. The AE, EE and HE extracts showed coagulant activity by the PT test, and the EE showed anticoagulant activity by the aPTT. When induced by ADP, the AE, EE and HE extracts showed 50% inhibitory concentration values (IC50, µg/mL of 450.5 ± 50.7, 511.2 ± 35.5 and 394.4 ± 8.9, respectively, and when induced by ADR showed values of 438.7 ± 5.2, 21.0 ± 1.9 and 546.9 ± 49.9, respectively. The EE showed inhibitory effect on the aggregation. The phytochemical characterization was suggestive of the presence of flavonoids and coumarins, which can be attributed in part to the biological effects studied.

  3. Reduced mRNA expression of PTGDS in peripheral blood mononuclear cells of rapid-cycling bipolar disorder patients compared with healthy control subjects

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Peijs, Lone; Kessing, Lars Vedel;

    2015-01-01

    BACKGROUND: Disturbances related to the arachidonic acid cascade and prostaglandin metabolism may be involved in the pathophysiology of bipolar disorder, as supported by a recent genome-wide association study meta-analysis; however, evidence from clinical studies on a transcriptional level...... disorder. The sample size was limited; replication of the findings in larger, independent samples is warranted to further explore the role of the arachidonic acid cascade and prostaglandin metabolism as a potential therapeutic target in bipolar disorder....... that mRNA expression of PTGDS and AKR1C3 is deregulated in rapid-cycling disorder patients in a euthymic or current affective state compared with healthy control subjects, and that expression alters with affective states. METHODS: PTGDS and AKR1C3 mRNA expression in peripheral blood mononuclear cells...

  4. Blood smear

    Science.gov (United States)

    ... of RBCs due to body destroying them ( immune hemolytic anemia ) Low number of RBCs due to some red ... of Heinz bodies may indicate: Alpha thalassemia Congenital hemolytic anemia Disorder in which red blood cells break down ...

  5. Automated platelet counters: a comparative evaluation of latest instrumentation.

    Science.gov (United States)

    Mayer, K; Chin, B; Magnes, J; Thaler, H T; Lotspeich, C; Baisley, A

    1980-08-01

    An extensive evaluation of performance characteristics and accuracy of clinical results for two automated multiparameter whole-blood cell counters (the Coulter Counter Model S-Plus and the Ortho ELT-8) and two single-parameter semiautomated platelet counters (the J. T. Baker MK-4/HC and the Clay-Adams Ultra-Flo 100) is described. Results of comparative assays performed on more than 1,200 clinical specimens are analyzed. These results are compared with manual determinations where appropriate. Particular attention is accorded to the accuracy of platelet counts, especially at abnormal levels below 70 X 10(3)/cu mm, where falsely elevated platelet counts may lead to serious clinical consequences. Both multiparameter instruments yielded accurate results, with the exception of low values reported by the ELT-8 for mean corpuscular volumes above 100 cu micrometer. Results for platelet counts were accurate for most specimens on all four instruments; the ELT-8 was the most reliable (P < 0.01), especially for the critically low counts. Although no instrument is infallible in determining platelet counts at all levels, the authors conclude that addition of platelet-counting capability represents a significant advancement over existing instrumentation. PMID:7405891

  6. Platelet functional and transcriptional changes induced by intralipid infusion.

    Science.gov (United States)

    Beaulieu, Lea M; Vitseva, Olga; Tanriverdi, Kahraman; Kucukural, Alper; Mick, Eric; Hamburg, Naomi; Vita, Joseph; Freedman, Jane E

    2016-06-01

    Multiple studies have shown the effects of long-term exposure to high-fat or western diets on the vascular system. There is limited knowledge on the acute effects of high circulating fat levels, specifically on platelets, which have a role in many processes, including thrombosis and inflammation. This study investigated the effects of acute, high-fat exposure on platelet function and transcript profile. Twenty healthy participants were given an intravenous infusion of 20% Intralipid emulsion and heparin over 6 hours. Blood samples were taken prior to and the day after infusion to measure platelet function and transcript expression levels. Platelet aggregation was not significantly affected by Intralipid infusion, but, when mitochondria function was inhibited by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) or oligomycin, platelet aggregation was higher in the post-infusion state compared to baseline. Through RNA sequencing, and verified by RT-qPCR, 902 miRNAs and 617 mRNAs were affected by Intralipid infusion. MicroRNAs increased include miR-4259 and miR-346, while miR-517b and miR-517c are both decreased. Pathway analysis identified two clusters significantly enriched, including cell motility. In conclusion, acute exposure to high fat affects mitochondrial-dependent platelet function, as well as the transcript profile. PMID:26940969

  7. Crosstalk between platelets and PBMC: New evidence in wound healing.

    Science.gov (United States)

    Nami, Niccolò; Feci, Luca; Napoliello, Luca; Giordano, Antonio; Lorenzini, Sauro; Galeazzi, Mauro; Rubegni, Pietro; Fimiani, Michele

    2016-01-01

    Platelet-derived products have proven useful in accelerating healing processes and tissue regeneration. However, despite their widespread use in clinical practice, the cellular and molecular mechanisms involved have not yet been completely clarified. Recent studies show that interaction between platelet gel (PG) and peripheral blood mononuclear cells (PBMC) can result in activation of PBMC and production of several cytokines involved in wound healing and tissue repair. The aim of our study was to analyze whether crosstalk between platelets and PBMC can influence wound healing by modulating release of VEGF, bFGF and IL-10 by PBMC. Cultures of PBMC alone and co-cultures with autologous PG of 24 healthy volunteers were incubated under normoxia for 24 h. VEGF, bFGF and IL-10 concentration and expression were then analyzed in supernatants by ELISA and by real-time RT-PCR. We observed a down-regulation of VEGF and bFGF release and an up-regulation of IL-10 release in co-cultures of PBMC and PG. Platelets are not only important in the early stages of the healing process (clot formation, direct release of growth factors), but also can influence the whole process of tissue regeneration by modulating synthesis and release of VEGF, bFGF and IL-10 by PBMC. These effects could give platelets a new key role in the control of healing processes and provide insights into the clinical success of platelet-derived products in many medical fields. PMID:26030799

  8. The role of plasma lipid photo-oxidation in the decrease of the aggregation of platelets under UV irradiation

    International Nuclear Information System (INIS)

    Change of platelet aggregation dependent on blood plasma under irradiation of plasma enriched with platelets and serium (1) as well as the role of peroxide photooxidation on non-saturated fatty acids (2) have been studied. Based on the obtained data it is concluded that peroxide photooxidation and stimulation of dark oxidation of their lipids under UV-radiation effect on blood plasma or serium. Products of these reactions weaken aggregation of platelets suspended in serum (plasma). Platelets destroy products of peroxide oxidation of plasma lipids, and as a result aggregation of cells is gradually reduced under incubation of platelet and plasma mixture irradiatted in darkness. It is supposed that photooxidation of blood lipids produces curative properties to blood under UV-radiation

  9. New gene functions in megakaryopoiesis and platelet formation

    NARCIS (Netherlands)

    Gieger, Christian; Radhakrishnan, Aparna; Cvejic, Ana; Tang, Weihong; Porcu, Eleonora; Pistis, Giorgio; Serbanovic-Canic, Jovana; Elling, Ulrich; Goodall, Alison H.; Labrune, Yann; Lopez, Lorna M.; Maegi, Reedik; Meacham, Stuart; Okada, Yukinori; Pirastu, Nicola; Sorice, Rossella; Teumer, Alexander; Voss, Katrin; Zhang, Weihua; Ramirez-Solis, Ramiro; Bis, Joshua C.; Ellinghaus, David; Goegele, Martin; Hottenga, Jouke-Jan; Langenberg, Claudia; Kovacs, Peter; O'Reilly, Paul F.; Shin, So-Youn; Esko, Toenu; Hartiala, Jaana; Kanoni, Stavroula; Murgia, Federico; Parsa, Afshin; Stephens, Jonathan; van der Harst, Pim; van der Schoot, C. Ellen; Allayee, Hooman; Attwood, Antony; Balkau, Beverley; Bastardot, Francois; Basu, Saonli; Baumeister, Sebastian E.; Biino, Ginevra; Bomba, Lorenzo; Bonnefond, Amelie; Cambien, Francois; Chambers, John C.; Cucca, Francesco; D'Adamo, Pio; Davies, Gail; de Boer, Rudolf A.; de Geus, Eco J. C.; Doering, Angela; Elliott, Paul; Erdmann, Jeanette; Evans, David M.; Falchi, Mario; Feng, Wei; Folsom, Aaron R.; Frazer, Ian H.; Gibson, Quince D.; Glazer, Nicole L.; Hammond, Chris; Hartikainen, Anna-Liisa; Heckbert, Susan R.; Hengstenberg, Christian; Hersch, Micha; Illig, Thomas; Loos, Ruth J. F.; Jolley, Jennifer; Khaw, Kay Tee; Kuehnel, Brigitte; Kyrtsonis, Marie-Christine; Lagou, Vasiliki; Lloyd-Jones, Heather; Lumley, Thomas; Mangino, Massimo; Maschio, Andrea; Mateo Leach, Irene; McKnight, Barbara; Memari, Yasin; Mitchell, Braxton D.; Montgomery, Grant W.; Nakamura, Yusuke; Nauck, Matthias; Navis, Gerjan; Noethlings, Ute; Nolte, Ilja M.; Porteous, David J.; Pouta, Anneli; Pramstaller, Peter P.; Pullat, Janne; Ring, Susan M.; Rotter, Jerome I.; Ruggiero, Daniela; Ruokonen, Aimo; Sala, Cinzia; Samani, Nilesh J.; Sambrook, Jennifer; Schlessinger, David; Schreiber, Stefan; Schunkert, Heribert; Scott, James; Smith, Nicholas L.; Snieder, Harold; Starr, John M.; Stumvoll, Michael; Takahashi, Atsushi; Tang, W. H. Wilson; Taylor, Kent; Tenesa, Albert; Thein, Swee Lay; Toenjes, Anke; Uda, Manuela; Ulivi, Sheila; van Veldhuisen, Dirk J.; Visscher, Peter M.; Voelker, Uwe; Wichmann, H-Erich; Wiggins, Kerri L.; Willemsen, Gonneke; Yang, Tsun-Po; Zhao, Jing Hua; Zitting, Paavo; Bradley, John R.; Dedoussis, George V.; Gasparini, Paolo; Hazen, Stanley L.; Metspalu, Andres; Pirastu, Mario; Shuldiner, Alan R.; van Pelt, L. Joost; Zwaginga, Jaap-Jan; Boomsma, Dorret I.; Deary, Ian J.; Franke, Andre; Froguel, Philippe; Ganesh, Santhi K.; Jarvelin, Marjo-Riitta; Martin, Nicholas G.; Meisinger, Christa; Psaty, Bruce M.; Spector, Timothy D.; Wareham, Nicholas J.; Akkerman, Jan-Willem N.; Ciullo, Marina; Deloukas, Panos; Greinacher, Andreas; Jupe, Steve; Kamatani, Naoyuki; Khadake, Jyoti; Kooner, Jaspal S.; Penninger, Josef; Prokopenko, Inga; Stemple, Derek; Toniolo, Daniela; Wernisch, Lorenz; Sanna, Serena; Hicks, Andrew A.; Rendon, Augusto; Ferreira, Manuel A.; Ouwehand, Willem H.; Soranzo, Nicole

    2011-01-01

    Platelets are the second most abundant cell type in blood and are essential for maintaining haemostasis. Their count and volume are tightly controlled within narrow physiological ranges, but there is only limited understanding of the molecular processes controlling both traits. Here we carried out a

  10. Spurious rise in the automated platelet count because of bacteria

    OpenAIRE

    Kakkar, N

    2004-01-01

    The era of automation in haematology, although improving the accuracy and precision of results, has also introduced the laboratory haematologist to a vast array of spurious parameters. The identification of these results is important so that inappropriate management decisions are avoided. The case presented here illustrates a spuriously raised automated platelet count resulting from bacterial overgrowth in the blood sample.

  11. Analysis on blood glucose metabolic disorders in critically ill neonates%危重新生儿血糖代谢紊乱相关因素分析

    Institute of Scientific and Technical Information of China (English)

    李艳秋; 赵军

    2012-01-01

    目的:对危重新生儿血糖代谢紊乱的相关因素进行调查分析,为临床治疗提供参考依据.方法:分析2007年6月~2011年6月168例危重新生儿血糖代谢紊乱的形成原因.结果:168例血糖代谢紊乱患者中,低血糖症者97例,高血糖症者42例,二者兼有者29例.血糖代谢紊乱与胎龄和出生体重呈负相关,而且在轻度窒息的情形下低血糖症状较多,重度窒息的情况下高血糖症状较多.结论:对危重新生儿血糖代谢紊乱相关因素的分析,可以及时发现和治疗病症,减少患儿日后的痛苦.%Objective; To investigate and analyze the related factors of blood glucose metabolic disorders in critically ill neonates, provide reference for clinical treatment. Methods; The causes of blood glucose metabolic disorders in 168 critically ill neonates who were treated in the hospital from June 2007 to June 2011 were analyzed. Results; Among 168 neonates with blood glucose metabolic disorders, 97 neonates were found with hypoglycemia, 42 neonates were found with hyperglycemia, and 29 neonates were found with both of the above -mentioned diseases. There was a negative correlation between blood glucose metabolic disorders and birth weight, hypoglycemia was commonly found under the circumstance of mild asphyxia, and hyperglycemia was commonly found under the circumstance of severe asphyxia. Conclusion; Blood glucose metabolic disorders can be diagnosed and cured timely through analyzing the related factors of blood glucose metabolic disorders in critically ill neonates to reduce future pains of the neonates.

  12. Platelet proteomics in cardiovascular diseases

    OpenAIRE

    Paula Vélez; Ángel García

    2015-01-01

    In recent years, platelet proteomics has been applied successfully to the study of cardiovascular diseases (CVDs). It is very well known that platelets play a pivotal role in the pathophysiological mechanisms underlying many CVDs, especially acute coronary syndromes (ACSs), since they are implied in thrombus formation after atheroma plaque rupture. This is the reason why molecules involved in platelet activation and aggregation are primary targets for treatment of ACSs. Many efforts are aimed...

  13. Platelets actively sequester angiogenesis regulators

    OpenAIRE

    Lakka Klement, Giannoula; Yip, Tai-Tung; Cassiola, Flavia; Kikuchi, Lena; Cervi, David; Podust, Vladimir; Italiano, Joseph E.; Wheatley, Erin; Abou-Slaybi, Abdo; Bender, Elise; Almog, Nava; Kieran, Mark W.; Folkman, Judah

    2009-01-01

    Clinical trials with antiangiogenic agents have not been able to validate plasma or serum levels of angiogenesis regulators as reliable markers of cancer presence or therapeutic response. We recently reported that platelets contain numerous proteins that regulate angiogenesis. We now show that accumulation of angiogenesis regulators in platelets of animals bearing malignant tumors exceeds significantly their concentration in plasma or serum, as well as their levels in platelets from non–tumor...

  14. Platelet surface-associated activation and secretion-mediated inhibition of coagulation factor XII.

    Science.gov (United States)

    Zakharova, Natalia V; Artemenko, Elena O; Podoplelova, Nadezhda A; Sveshnikova, Anastasia N; Demina, Irina A; Ataullakhanov, Fazly I; Panteleev, Mikhail A

    2015-01-01

    Coagulation factor XII (fXII) is important for arterial thrombosis, but its physiological activation mechanisms are unclear. In this study, we elucidated the role of platelets and platelet-derived material in fXII activation. FXII activation was only observed upon potent platelet stimulation (with thrombin, collagen-related peptide, or calcium ionophore, but not ADP) accompanied by phosphatidylserine exposure and was localised to the platelet surface. Platelets from three patients with grey platelet syndrome did not activate fXII, which suggests that platelet-associated fXII-activating material might be released from α-granules. FXII was preferentially bound by phosphotidylserine-positive platelets and annexin V abrogated platelet-dependent fXII activation; however, artificial phosphotidylserine/phosphatidylcholine microvesicles did not support fXII activation under the conditions herein. Confocal microscopy using DAPI as a poly-phosphate marker did not reveal poly-phosphates associated with an activated platelet surface. Experimental data for fXII activation indicates an auto-inhibition mechanism (ki/ka = 180 molecules/platelet). Unlike surface-associated fXII activation, platelet secretion inhibited activated fXII (fXIIa), particularly due to a released C1-inhibitor. Platelet surface-associated fXIIa formation triggered contact pathway-dependent clotting in recalcified plasma. Computer modelling suggests that fXIIa inactivation was greatly decreased in thrombi under high blood flow due to inhibitor washout. Combined, the surface-associated fXII activation and its inhibition in solution herein may be regarded as a flow-sensitive regulator that can shift the balance between surface-associated clotting and plasma-dependent inhibition, which may explain the role of fXII at high shear and why fXII is important for thrombosis but negligible in haemostasis. PMID:25688860

  15. Platelet surface-associated activation and secretion-mediated inhibition of coagulation factor XII.

    Directory of Open Access Journals (Sweden)

    Natalia V Zakharova

    Full Text Available Coagulation factor XII (fXII is important for arterial thrombosis, but its physiological activation mechanisms are unclear. In this study, we elucidated the role of platelets and platelet-derived material in fXII activation. FXII activation was only observed upon potent platelet stimulation (with thrombin, collagen-related peptide, or calcium ionophore, but not ADP accompanied by phosphatidylserine exposure and was localised to the platelet surface. Platelets from three patients with grey platelet syndrome did not activate fXII, which suggests that platelet-associated fXII-activating material might be released from α-granules. FXII was preferentially bound by phosphotidylserine-positive platelets and annexin V abrogated platelet-dependent fXII activation; however, artificial phosphotidylserine/phosphatidylcholine microvesicles did not support fXII activation under the conditions herein. Confocal microscopy using DAPI as a poly-phosphate marker did not reveal poly-phosphates associated with an activated platelet surface. Experimental data for fXII activation indicates an auto-inhibition mechanism (ki/ka = 180 molecules/platelet. Unlike surface-associated fXII activation, platelet secretion inhibited activated fXII (fXIIa, particularly due to a released C1-inhibitor. Platelet surface-associated fXIIa formation triggered contact pathway-dependent clotting in recalcified plasma. Computer modelling suggests that fXIIa inactivation was greatly decreased in thrombi under high blood flow due to inhibitor washout. Combined, the surface-associated fXII activation and its inhibition in solution herein may be regarded as a flow-sensitive regulator that can shift the balance between surface-associated clotting and plasma-dependent inhibition, which may explain the role of fXII at high shear and why fXII is important for thrombosis but negligible in haemostasis.

  16. Increased mean platelet volume in type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Ezgi Coşkun Yenigün

    2014-03-01

    Full Text Available Objective: Platelet functions have important roles in the development of vascular complications in diabetic patients. Platelets with increased volume have increased activity compared to smaller ones; therefore, mean platelet volume (MPV is used as a marker for platelet activity. In the present study, we evaluated MPV in patients with type II diabetes mellitus (DM and its associations with diabetic microvascular and macrovascular complications. Methods: Consecutive type II diabetic patients were screened from outpatient clinic of Internal Medicine Department of Diskapı Yıldırım Beyazıt Education and Researsch Hospital, Ankara, Turkey. A total of 48 patients with type II DM and 30 age and gender matched healthy subjects constituted the study population. For all subjects a complete blood count including MPV, fasting blood glucose level and lipid parameters were studied. In diabetic patients, duration of diabetes and HbA1C level, presence of microvascular and macrovascular complications were noted additively. Mean platelet volume was compared between diabetic patients and healthy counterparents. Then, among diabetic patients, MPV was compared between the ones with and without microvascular and macrovascular complications. Results: Mean platelet volume was found significantly higher in diabetic patients compared to non-diabetic healthy subjects. Diabetic patients with at least one of the microvascular complications had significantly higher MPV than those without microvascular damage.Higher MPV levels have also been shown in diabetics with macrovascular complications compared to the ones without macrovascular disease. Conclusion: Mean platelet volume was found to be higher in type II diabetics and those having any of microvascular or macrovascular diabetic complications.

  17. Hemodynamic aspects of reduced platelet adhesion on bioinspired microstructured surfaces.

    Science.gov (United States)

    Pham, Tam Thanh; Wiedemeier, Stefan; Maenz, Stefan; Gastrock, Gunter; Settmacher, Utz; Jandt, Klaus D; Zanow, Jürgen; Lüdecke, Claudia; Bossert, Jörg

    2016-09-01

    Occlusion by thrombosis due to the absence of the endothelial cell layer is one of the most frequent causes of failure of artificial vascular grafts. Bioinspired surface structures may have a potential to reduce the adhesion of platelets contributing to hemostasis. The aim of this study was to investigate the hemodynamic aspects of platelet adhesion, the main cause of thrombosis, on bioinspired microstructured surfaces mimicking the endothelial cell morphology. We tested the hypothesis that platelet adhesion is statistically significantly reduced on bioinspired microstructured surfaces compared to unstructured surfaces. Platelet adhesion as a function of the microstructure dimensions was investigated under flow conditions on polydimethylsiloxane (PDMS) surfaces by a combined experimental and theoretical approach. Platelet adhesion was statistically significantly reduced (by up to 78%; p≤0.05) on the microstructured PDMS surfaces compared to that on the unstructured control surface. Finite element method (FEM) simulations of blood flow dynamic revealed a micro shear gradient on the microstructure surfaces which plays a pivotal role in reducing platelet adhesion. On the surfaces with the highest differences of the shear stress between the top of the microstructures and the ground areas, platelet adhesion was reduced most. In addition, the microstructures help to reduce the interaction strength between fluid and surfaces, resulting in a larger water contact angle but no higher resistance to flow compared to the unstructured surface. These findings provide new insight into the fundamental mechanisms of reducing platelet adhesion on microstructured bioinspired surfaces and may lay the basis for the development of innovative next generation artificial vascular grafts with reduced risk of thrombosis. PMID:27239904

  18. Effect of taurine on platelets and the plasma coagulation system.

    Science.gov (United States)

    Miglis, Mitchell; Wilder, Donna; Reid, Thomas; Bakaltcheva, Irina

    2002-02-01

    It is not yet clear what exact mechanisms are at work in hibernating animals that prevent clot formation and maintain tissue perfusion under conditions of very slow blood flow and increased blood viscosity brought about by the low temperatures. It has been shown that the total amino acid pool increases more then two fold in hibernating animals with taurine accounting for about 50% of this increase [Storey et al., Proc Natl Acad Sci USA 1988; 85(21): 8350-4]. This work investigates the effect of taurine on platelets and the plasma coagulation system. Taurine was added at different concentrations in the range between 5 and 25 mM to donor plasma. Using STA/STA Compact coagulation analyzer the following tests were performed: prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT). At the highest concentration tested (25 mM) taurine prolonged TT by 9%. The prolongation was statistically significant but not clinically significant retaining TT within normal limits (16.7-20.7 s). PT and APTT remained unchanged by taurine. The effect of taurine on platelets was assessed by platelet aggregation by thrombin, extent of platelet shape change (ESC) induced by ADP, and thrombelastography. Taurine at 5 mM final concentration inhibited platelet aggregation by 10%. Increasing taurine concentration to 25 mM did not result in a further augmentation of the inhibitory effect. ESC was unaffected by taurine. Clot strength determined by thrombelastography also remained unchanged by taurine. PMID:11918831

  19. Novel aspects of platelet aggregation

    Directory of Open Access Journals (Sweden)

    Roka-Moya Y. M.

    2014-01-01

    Full Text Available The platelet aggregation is an important process, which is critical for the hemostatic plug formation and thrombosis. Recent studies have shown that the platelet aggregation is more complex and dynamic than it was previously thought. There are several mechanisms that can initiate the platelet aggregation and each of them operates under specific conditions in vivo. At the same time, the influence of certain plasma proteins on this process should be considered. This review intends to summarize the recent data concerning the adhesive molecules and their receptors, which provide the platelet aggregation under different conditions.

  20. Low sodium diet in essential hypertension- Effect on blood cell ions and hemodynamic parameters

    OpenAIRE

    Krzesinski, Jean-Marie; Du, Fenghe; Pequeux, Marie-Louise; Rorive, Georges

    1992-01-01

    The influence of salt restriction for 3 months on blood pressure, peripheral vascular resistance (observed by occlusive plethysmography), erythrocyte sodium, platelet calcium, and pH, was studied in eight untreated essential hypertensive patients. A low salt diet decreases blood pressure, vascular resistances, erythrocyte sodium, and platelet calcium, but not platelet pH. A strong positive correlation was noted between baseline platelet calcium and vascular resistances (r=0.95, P < .01). Bu...