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Sample records for blood platelet disorders

  1. PREGNANCY WITH PLATELET FUNCTION DISORDER

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    Sheila K

    2014-01-01

    Full Text Available latelets play a vital role in haemostasis . Antenatal patients with platelet function disorders should be managed in tertiary care centres that are well equipped to tackle any obstetric haemorrhage that can ensue during labour and delivery . Primi gravida was admitted for safe confinement . She had been evaluated earlier for complaints of multiple episodes of mucosal bleeding . On evaluation she had nor mal platelet counts and coagulation factor assay was normal . Platelet aggregometry revealed mild disorder of platelet aggregation . She was planned for induction of labour after arranging enough blood and blood products . She got into active labour and was p ut on syntocinon augmentation . She had emergency Caesarean section for foetal distress . Oxytocics were given proactively . Intraoperatively platelet transfusions and tranexamic acid infusion were given . Complete haemostasis was achieved . She had an uneventf ul postoperative period . Patients with functional platelet disorders can be successfully managed with local application of antifibrinolytic agents like tranexamic acid , in case of minor bleeds . Platelet transfusions are very effective in tackling major ble eds , especially during surgeries and for obstetric indications . If a patient has the history of clinically significant bleeding suggestive of platelet dysfunction , appropriate platelet function tests should be obtained so that the risk of bleeding can be adequately assessed and therapy chosen more rationally . . In obstetric practice the response of such patients to platelet transfusions has been excellent

  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.

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    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.

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    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. Laboratory testing for platelet function disorders.

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    Israels, S J

    2015-05-01

    Platelet function testing is both complex and labor intensive. A stepwise approach to the evaluation of patients with suspected platelet disorders will optimize the use of laboratory resources, beginning with an appropriate clinical evaluation to determine whether the bleeding is consistent with a defect of primary hemostasis. Bleeding assessment tools, evaluation of platelet counts, and review of peripheral blood cell morphology can aid the initial assessment. For patients requiring further laboratory testing, platelet aggregometry, secretion assays, and von Willebrand factor assays are the most useful next steps and will direct further specialized testing including flow cytometry, electron microscopy, and molecular diagnostics. Guidelines and recommendations for standardizing platelet function testing, with a particular focus on light transmission aggregometry, are available and can provide a template for clinical laboratories in establishing procedures that will optimize diagnosis and assure quality results. This review outlines an approach to platelet function testing and reviews testing methods available to clinical laboratories.

  6. Image analysis of blood platelets adhesion.

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    Krízová, P; Rysavá, J; Vanícková, M; Cieslar, P; Dyr, J E

    2003-01-01

    Adhesion of blood platelets is one of the major events in haemostatic and thrombotic processes. We studied adhesion of blood platelets on fibrinogen and fibrin dimer sorbed on solid support material (glass, polystyrene). Adhesion was carried on under static and dynamic conditions and measured as percentage of the surface covered with platelets. Within a range of platelet counts in normal and in thrombocytopenic blood we observed a very significant decrease in platelet adhesion on fibrin dimer with bounded active thrombin with decreasing platelet count. Our results show the imperative use of platelet poor blood preparations as control samples in experiments with thrombocytopenic blood. Experiments carried on adhesive surfaces sorbed on polystyrene showed lower relative inaccuracy than on glass. Markedly different behaviour of platelets adhered on the same adhesive surface, which differed only in support material (glass or polystyrene) suggest that adhesion and mainly spreading of platelets depends on physical quality of the surface. While on polystyrene there were no significant differences between fibrin dimer and fibrinogen, adhesion measured on glass support material markedly differed between fibrin dimer and fibrinogen. We compared two methods of thresholding in image analysis of adhered platelets. Results obtained by image analysis of spreaded platelets showed higher relative inaccuracy than results obtained by image analysis of platelets centres and aggregates.

  7. Extending The Shelf Life Of Blood Platelets

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    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.

  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 pacemaker can. METHODS: Platelet-rich plasma was prepared from two healthy subjects. Platelet reactivity to the agonist ADP was tested in paired samples in an aggregometer in a case/control setup. RESULTS: Eighteen of 46 tested pairs of platelet-rich plasma showed increased reactivity in the paced sample......; 26 were unchanged while two showed decreased reactivity in the paced sample. Using a two-sided sign test, the null hypothesis was rejected (P = 0.0004). CONCLUSIONS: The study demonstrates increased reactivity to ADP in platelets exposed in vitro to stimulation by pacemaker current. The clinical...

  9. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

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    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. Adjusting MtDNA Quantification in Whole Blood for Peripheral Blood Platelet and Leukocyte Counts

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    Gonzalez-Lazaro, Monica; Moreno-Loshuertos, Raquel; Fernandez-Silva, Patricio; Enriquez, Jose Antonio; Laclaustra, Martin

    2016-01-01

    Alterations of mitochondrial DNA copy number (mtDNAcn) in the blood (mitochondrial to nuclear DNA ratio) appear associated with several systemic diseases, including primary mitochondrial disorders, carcinogenesis, and hematologic diseases. Measuring mtDNAcn in DNA extracted from whole blood (WB) instead of from peripheral blood mononuclear cells or buffy coat may yield different results due to mitochondrial DNA present in platelets. The aim of this work is to quantify the contribution of platelets to mtDNAcn in whole blood [mtDNAcn(WB)] and to propose a correction formula to estimate leukocytes' mtDNAcn [mtDNAcn(L)] from mtDNAcn(WB). Blood samples from 10 healthy adults were combined with platelet-enriched plasma and saline solution to produce artificial blood preparations. Aliquots of each sample were combined with five different platelet concentrations. In 46 of these blood preparations, mtDNAcn was measured by qPCR. MtDNAcn(WB) increased 1.07 (95%CI 0.86, 1.29; p<0.001) per 1000 platelets present in the preparation. We proved that leukocyte count should also be taken into account as mtDNAcn(WB) was inversely associated with leukocyte count; it increased 1.10 (95%CI 0.95, 1.25, p<0.001) per unit increase of the ratio between platelet and leukocyte counts. If hematological measurements are available, subtracting 1.10 the platelets/leukocyte ratio from mtDNAcn(WB) may serve as an estimation for mtDNAcn(L). Both platelet and leukocyte counts in the sample are important sources of variation if comparing mtDNAcn among groups of patients when mtDNAcn is measured in DNA extracted from whole blood. Not taking the platelet/leukocyte ratio into account in whole blood measurements, may lead to overestimation and misclassification if interpreted as leukocytes' mtDNAcn. PMID:27736919

  11. 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

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

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    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

  13. Platelet concentrates, from whole blood or collected by apheresis?

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    van der Meer, Pieter F

    2013-04-01

    Platelet concentrates can be isolated from donated whole blood with the platelet-rich plasma-method or the buffy coat-method. Alternatively, platelets can be obtained by apheresis, harvesting the platelets but returning all other cells to the donor. The quality and characteristics of platelets during storage are affected by a number of factors, such as anticoagulant, centrifugation and processing after collection, and pre- or post storage pooling, but when comparing literature on the various methods, most differences balance out. To have sufficient platelets to treat an adult patient, whole-blood-derived platelet concentrates need pooling of multiple donations, thereby increasing the risk of infectious agent transmission at least two-fold as compared with apheresis units. Allo immunization rates, acute reaction rates, and transfusion related acute lung injury rates are not different. Apheresis donation procedures have fewer adverse events. All these factors need to be considered and weighed when selecting a method of platelet collection for a blood center.

  14. Decreased mean platelet volume in panic disorder

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    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 

  15. The effects of selective serotonin reuptake inhibitors on platelet function in whole blood and platelet concentrates.

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    Reikvam, Anne-Grete; Hustad, Steinar; Reikvam, Håkon; Apelseth, Torunn Oveland; Nepstad, Ina; Hervig, Tor Audun

    2012-01-01

    Several studies report that patients who are treated with selective serotonin reuptake inhibitors (SSRIs) for depression may have increased risk of bleeding, particularly from the gastrointestinal tract. This may be related to low intraplatelet serotonin concentrations. Several blood banks do not store platelets from donors using SSRIs for transfusion, although the possible effects of SSRIs on platelet storage are not documented. We conducted a case-control pilot study of apheresis platelet concentrates prepared from donors using SSRIs (n=8) and from donors without medication (n=10). The platelet concentrates were stored for 5 days. Light transmission aggregometry (LTA), thrombelastography (TEG), and flow cytometric analyses were preformed for in vitro measurements of platelet function. Platelet function and platelet serotonin content were investigated in whole blood and in platelet concentrates stored for up to 5 days. LTA, TEG, and flow cytometric analysis of glycoprotein expression did not reveal any significant differences between the two groups. All 18 platelet concentrates performed well according to the standards set for platelet quality in relation to transfusion. Blood donors using SSRIs had significantly lower platelet serotonin compared to blood donors without medication. The results from our pilot study indicate that platelets from donors using SSRIs may be suitable for transfusion after storage for 5 days, but further laboratory and clinical studies are necessary to confirm this.

  16. Blood platelet counts, morphology and morphometry in lions, Panthera leo

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    L. Du Plessis

    2009-09-01

    Full Text Available Due to logistical problems in obtaining sufficient blood samples from apparently healthy animals in the wild in order to establish normal haematological reference values, only limited information regarding the blood platelet count and morphology of free-living lions (Panthera leo is available. This study provides information on platelet counts and describes their morphology with particular reference to size in two normal, healthy and free-ranging lion populations. Blood samples were collected from a total of 16 lions. Platelet counts, determined manually, ranged between 218 and 358 x 109/ℓ. Light microscopy showed mostly activated platelets of various sizes with prominent granules. At the ultrastructural level the platelets revealed typical mammalian platelet morphology. However, morphometricanalysis revealed a significant difference (P < 0.001 in platelet size between the two groups of animals. Basic haematological information obtained in this study may be helpful in future comparative studies between animals of the same species as well as in other felids.

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

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    Maria José Dantas Coêlho

    2011-01-01

    Full Text Available 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 and 5 of storage. Additionally a leukocyte count was done only on day 1 and microbiological tests on day 5 of storage. Collagen and adenosine diphosphate were used as inducing agonists for platelet aggregation testing. RESULTS: Donor whole blood had normal aggregation (aggregation with adenosine diphosphate = 67% and with collagen = 78%. The median aggregation in platelet concentrates with adenosine diphosphate was low throughout storage (18% on day 1, 7% on day 3 and 6% on day 5 and the median aggregation with collagen was normal only on day 1 and low thereafter (54.4% on day 1, 20.5% on day 3 and 9% on day 5. CONCLUSION: Although the results were within the norms required by law, platelet concentrates had low aggregation rates. We suggest the inclusion of a functional assessment test for the quality control of platelet concentrates for a more effective response to platelet replacement therapy.

  18. 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...

  19. Current and emerging approaches for evaluating platelet disorders.

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    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

  20. Inhibition of uptake of adenosine into human blood platelets

    NARCIS (Netherlands)

    Lips, J.P.M.; Sixma, J.J.; Trieschnigg, A.C.

    1980-01-01

    Adenosine transport into human blood platelets is mediated by two independent systems with different affinities. Both systems transport only purine nucleosides and no pyrimidine nucleosides. In experiments with differently substituted purine nucleosides, purines and analogues, differences in carrier

  1. Role of blood platelets in infection and inflammation.

    Science.gov (United States)

    Klinger, Matthias H F; Jelkmann, Wolfgang

    2002-09-01

    Blood platelets are here presented as active players in antimicrobial host defense and the induction of inflammation and tissue repair in addition to their participation in hemostasis. Megakaryopoiesis is inhibited after acute infection with viruses or bacteria. In contrast, chronic inflammation is often associated with reactive thrombocytosis. Platelets can bind and internalize pathogens and release microbicidal proteins that kill certain bacteria and fungi. By making cell-cell contacts with leukocytes and endothelial cells, platelets assist white blood cells in rolling, arrest and transmigration. On stimulation by bacteria or thrombin, platelets release the content of their alpha-granules, which include an arsenal of bioactive peptides, such as CC-chemokines and CXC-chemokines and growth factors for endothelial cells, smooth muscle cells and fibroblasts. Thus, integral to innate immunity, the tiny little platelets may become bombshells when irritated by pathogens.

  2. 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

    and compared three blood sampling tubes of different size: 1.8, 2.7, and 3.6 mL. All tubes were made of plastic and contained 3.2% sodium-citrate as anticoagulant. Platelet aggregation was investigated in 12 healthy individuals employing the Multiplate® Analyser comparing tubes of 3.6 mL and 1.8 mL. Platelet...... be preferred for RoTEM® analyses in order to minimise the volume of blood drawn. With regard to platelet aggregation analysed by impedance aggregometry tubes of different size cannot be used interchangeably. If platelet count is determined later than 10 min after blood sampling using tubes containing citrate...

  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. [The role of blood platelets in infections].

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    Micota, Bartłomiej; Sadowska, Beata; Różalska, Barbara

    2015-05-17

    Platelets are primarily associated with their main function, hemostasis, although it is known that these cells also exhibit biological activity in cancer progression, inflammation and infectious processes. During infection platelets, due to the expression of specific receptors - Toll-like receptors (TLRs) - which recognize molecular patterns associated with pathogens - pathogen-associated molecular patterns (PAMPs) - are activated by the presence of microorganism components and/or substances released from damaged cells/tissue. Further antimicrobial activity of platelets is based on their capacity for phagocytosis, generation of reactive oxygen species (ROS), and the synthesis, storage and release of proteins/peptides with antimicrobial activity. Another mechanism of platelet action is their immunomodulatory activity. It is based mainly on the ability to secrete chemotactic factors allowing the accumulation of professional immunocompetent cells at the site of infection, thus enhancing the effective eradication of an infectious agent. In chronic infections, platelets, due to release of numerous growth factors and various cytokines, support mechanisms of acquired immunity. They accelerate the maturation of dendritic cells, stimulate B cells to be immunoglobulin-producing plasma cells and potentiate the activity of T cells. Unfortunately, in certain situations (the existence of specific risk factors) the interaction of microorganisms with activated platelets may also be the cause of pathology within the cardiovascular system.

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

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    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

  6. 血液病患者单采血小板输注无效的原因及对策%Reasons for apheresis platelet transfusion refractory on patients with blood disorder and its countermeasures

    Institute of Scientific and Technical Information of China (English)

    沈胜建; 赵明峰; 张宇辰

    2014-01-01

    目的:探讨血液病患者单采血小板输注无效( PTR)发生率及其影响因素,为临床正确应用血小板制剂提供指导。方法回顾性分析单采血小板输注的70例患者318例次输注资料,通过计算血小板计数增加指数和血小板恢复百分率结合患者出血状况有无改善,判断血小板输注有效性,并讨论其影响因素及处理措施。结果急性白血病、再生障碍性贫血、骨髓异常综合征和特发性血小板减少性紫癜患者PTR发生率分别为22.1%、25.5%、38.3%和51.2%,四种类型的血液病患者血小板PTR发生率差别有统计学意义(P均<0.05);同种疾病无并发症患者PTR发生率低于有并发症者(P<0.05);无并发症患者PTR发生率随着输注次数的增加而上升(P<0.05)。未过滤白细胞与过滤白细胞患者PTR发生率比较差异有统计学意义( P<0.05)。结论疾病类型、有无并发症等因素影响血液病患者血小板输注的治疗效果,减少并发症、过滤白细胞可提高血小板的输注效果。%Objective To explore incidence rate and influence factor of apheresis platelet transfusion refractory ( PTR) on patients with blood disorder .Methods The data of 318 infusions for 70 patients subject to apheresis platelet infusion were retrospectively analyzed , by calculating corrected Count increment ( CCI ) and percent platelet recovery ( PPR) and combining hemorrhage improvement condition in patients , the effect of platelet transfusion were determined and influence factors and treatment measures were discussed .Results ①The PTR occurrence rate of acute leukemia (AL), aplastic anemia (AA), bone marrow abnormalities syndrome (MDS) and idiopathic thrombocytopenic purpura (ITP) in patients hit 22.1%, 25.5%, 38.3%and 22.1%respectively, the difference in platelet PTR rate in four types of blood diseases was statistically significant (P<0.05).②The difference

  7. Influence of caffeine on blood pressure and platelet aggregation

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    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.

  8. Blood Platelet Production: Optimization by Dynamic Programming and Simulation

    NARCIS (Netherlands)

    Haijema, R.; Wal, van der J.; Dijk, van N.M.

    2007-01-01

    Blood platelets are precious, as voluntarily supplied by donors, and highly perishable, with limited lifetimes of 5¿7 days. Demand is highly variable and uncertain. A practical production and inventory rule is strived for that minimizes shortages and spill. The demand and production are periodic, as

  9. 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

  10. 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.

  11. 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;

    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 resul...

  12. Platelet proteomics.

    Science.gov (United States)

    Zufferey, Anne; Fontana, Pierre; Reny, Jean-Luc; Nolli, Severine; Sanchez, Jean-Charles

    2012-01-01

    Platelets are small cell fragments, produced by megakaryocytes, in the bone marrow. They play an important role in hemostasis and diverse thrombotic disorders. They are therefore primary targets of antithrombotic therapies. They are implicated in several pathophysiological pathways, such as inflammation or wound repair. In blood circulation, platelets are activated by several pathways including subendothelial matrix and thrombin, triggering the formation of the platelet plug. Studying their proteome is a powerful approach to understand their biology and function. However, particular attention must be paid to different experimental parameters, such as platelet quality and purity. Several technologies are involved during the platelet proteome processing, yielding information on protein identification, characterization, localization, and quantification. Recent technical improvements in proteomics combined with inter-disciplinary strategies, such as metabolomic, transcriptomics, and bioinformatics, will help to understand platelets biological mechanisms. Therefore, a comprehensive analysis of the platelet proteome under different environmental conditions may contribute to elucidate complex processes relevant to platelet function regarding bleeding disorders or platelet hyperreactivity and identify new targets for antiplatelet therapy.

  13. 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, ...

  14. 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.

  15. Platelet-Rich Blood Derivatives for Stem Cell-Based Tissue Engineering and Regeneration

    NARCIS (Netherlands)

    Masoudi, E.A.; Ribas, J.; Kaushik, G.; Leijten, J.C.H.; Khademhosseini, A.

    2016-01-01

    Platelet-rich blood derivatives have been widely used in different fields of medicine and stem cell-based tissue engineering. They represent natural cocktails of autologous growth factors, which could provide an alternative for recombinant protein-based approaches. Platelet-rich blood derivatives, s

  16. 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

  17. The extract from hop cones (Humulus lupulus) as a modulator of oxidative stress in blood platelets.

    Science.gov (United States)

    Olas, Beata; Kolodziejczyk, Joanna; Wachowicz, Barbara; Jędrejek, Dariusz; Stochmal, Anna; Oleszek, Wiesław

    2011-01-01

    The plant Humulus lupulus is known as the raw material of the brewing industry. Hop cones, rich in polyphenolic compounds and acyl phloroglucides, are widely used to preserve beer and to give it a characteristic aroma and flavor. Hop cones have long been used for medicinal purposes. In particular, hop preparations were mainly recommended for the treatment of sleeping disorders. The antioxidative action of hop cones, however, is poorly understood. The aim of our present study was to investigate in vitro changes in human blood platelets induced by peroxynitrite (ONOO(-), the compound of particular importance for vascular thrombosis and inflammatory process) in the presence of hop cone extract (Humulus lupulus). The antioxidative action of the extract was also compared with the properties of a well-characterized antioxidative commercial monomeric polyphenol, resveratrol (3,4',5-trihydroxystilbene) in a model system in vitro. Various biomarkers of oxidative/nitrative stress, such as carbonyl groups, 3-nitrotyrosine and thiobarbituric acid reactive substances (TBARS) were estimated. The 3-nitrotyrosine formation and carbonyl group generation was assessed by the use of a competition ELISA test and ELISA test, respectively. Tested plant extract (12.5-50 µg/ml), like resveratrol, significantly inhibited protein carbonylation and nitration in the blood platelets treated with ONOO(-) (0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of platelet lipid peroxidation induced by ONOO(-). The present results indicate that the hope cone extract has in vitro protective effects against ONOO(-), such as induced oxidative/nitrative damage to the human platelet proteins and lipids. However, in comparative studies the extract was not found to be a more effective antioxidant than the solution of pure resveratrol.

  18. 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

  19. [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

  20. [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

  1. Era of blood component therapy: time for mandatory pre-donation platelet count for maximizing donor safety and optimizing quality of platelets.

    Science.gov (United States)

    Das, Sudipta Sekhar; Zaman, R U; Biswas, Dipak

    2013-12-01

    Blood bank regulatory agencies including the Drug and Cosmetics Act (DCA) of India do not mandate a predonation platelet count in whole blood donation. Mandating such practice will definitely optimize the quality of random donor platelets (RDP) in terms of platelet yield and patient therapeutic benefit. We observed poor platelet yield in RDP concentrates prepared at our center with a significant number not meeting the DCA guideline of ≥ 4.5 × 10(10) per bag processed from 450 ml of whole blood. Therefore we planned this study to evaluate the pre-donation hematological values in our blood donor population and effect of these values on the quality of platelet concentrates. The prospective study included 221 blood donors eligible for donating 450 ml of whole blood (WB). Following the departmental standard operating procedure (SOP) RDPs were prepared using the 'Top & Bottom' quadruple bag system and automated component extractor. Quality of RDP was assessed as per departmental protocol. All results were recorded and subsequently transcribed to SPSS working sheet. A significant (pplatelets reduced by 0.72 g/dl and 22.1 × 10(6)/ml respectively. Quality of RDPs in terms of platelet yield was significantly better (pplatelet count was >200 × 10(6)/ml. Although platelet yield significantly correlated with the donor platelet count however quality of RDPs in terms of red cell contamination showed no correlation with the donor hematocrit. Platelet yield in random donor platelets is a concern in Eastern India. A platelet yield of 4.5 × 10(10) per bag as mandated by the DCA of India was only achieved when the donor platelet count was >200 × 10(6)/ml. Posttransfusion platelet recovery (PPR) was unsatisfactory in the transfused patient. Introduction of pre-donation platelet count in whole blood donation will maximize donor safety and optimize patient platelet transfusion management.

  2. Vasopressin elevation of Na+/H+ exchange is inhibited by genistein in human blood platelets.

    Science.gov (United States)

    Aharonovits, O; Zik, M; Livne, A A; Granot, Y

    1992-12-01

    The regulation of intracellular Na+ and pHi in human blood platelets is known to be controlled by the function of the Na+/H+ exchanger. The phosphorylation state of the Na+/H+ exchanger which determines the exchanger activity in human blood platelets is regulated by the activities of protein kinases and protein phosphatases. Observations in this study indicate that arginine vasopressin (AVP) that interacts with a V1 receptor, activates the Na+/H+ exchange in human blood platelets through a genistein-inhibited mechanism. The AVP-activated Na+/H+ exchange is probably not regulated by protein kinase C (PKC), since this activation is not inhibited by staurosporine. The multiple ways in which platelet Na+/H+ exchange can be modulated may indicate the critical role played by this exchanger in the homeostasis control of pHi in human blood platelets.

  3. 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.

  4. 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

  5. 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

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

    Science.gov (United States)

    Jones, Letitia D; Jackson, Joseph W; Maggirwar, Sanjay B

    2016-01-01

    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.

  7. 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.

  8. 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

  9. 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.

  10. Proteomics meets blood banking: identification of protein targets for the improvement of platelet quality.

    Science.gov (United States)

    Schubert, Peter; Devine, Dana V

    2010-01-01

    Proteomics has brought new perspectives to the fields of hematology and transfusion medicine in the last decade. The steady improvement of proteomic technology is propelling novel discoveries of molecular mechanisms by studying protein expression, post-translational modifications and protein interactions. This review article focuses on the application of proteomics to the identification of molecular mechanisms leading to the deterioration of blood platelets during storage - a critical aspect in the provision of platelet transfusion products. Several proteomic approaches have been employed to analyse changes in the platelet protein profile during storage and the obtained data now need to be translated into platelet biochemistry in order to connect the results to platelet function. Targeted biochemical applications then allow the identification of points for intervention in signal transduction pathways. Once validated and placed in a transfusion context, these data will provide further understanding of the underlying molecular mechanisms leading to platelet storage lesion. Future aspects of proteomics in blood banking will aim to make use of protein markers identified for platelet storage lesion development to monitor proteome changes when alterations such as the use of additive solutions or pathogen reduction strategies are put in place in order to improve platelet quality for patients.

  11. 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

  12. External quality assessment of platelet disorder investigations: results of international surveys on diagnostic tests for dense granule deficiency and platelet aggregometry interpretation.

    Science.gov (United States)

    Hayward, Catherine P M; Moffat, Karen A; Plumhoff, Elizabeth; Timleck, Marnie; Hoffman, Suzanne; Spitzer, Ernie; Van Cott, Elizabeth M; Meijer, Piet

    2012-09-01

    The quality of platelet aggregation and dense granule deficiency testing is important for diagnosing platelet function disorders. After a successful pilot exercise on diagnosing platelet dense granule deficiency by electron microscopy (EM), the North American Specialized Coagulation Laboratory Association (NASCOLA) has launched regular external quality assurance (EQA) for dense granule EM, as well as for the interpretation of platelet aggregation findings. EQA records were analyzed to assess performance. For EM EQA, between 2009 and 2011, there was excellent performance in distinguishing normal from dense granule-deficient samples and good (>70%) agreement on classifying most electron dense structures in platelets. For aggregation EQA, some normal variants were misclassified and overall case interpretations were more acceptable for rare disorders than for common findings. NASCOLA experiences with these EQAs indicate that there is a need to improve the quality of platelet disorder evaluations. For aggregometry interpretations, deficits in performance could be addressed by translating guideline recommendations into practice.

  13. Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

    Energy Technology Data Exchange (ETDEWEB)

    Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V. (Mt. Sinai Medical Center, New York, NY (USA))

    1989-09-01

    Blood-pool subtraction has been proposed to enhance {sup 111}In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging.

  14. Platelet proteomics and its advanced application for research of blood stasis syndrome and activated blood circulation herbs of Chinese medicine.

    Science.gov (United States)

    Liu, Yue; Yin, Huijun; Chen, Keji

    2013-11-01

    The development of novel and efficient antiplatelet agents that have few adverse effects and methods that improve antiplatelet resistance has long been the focus of international research on the prevention and treatment of cardiovascular and cerebrovascular diseases. Recent advances in platelet proteomics have provided a technology platform for high-quality research of platelet pathophysiology and the development of new antiplatelet drugs. The study of blood stasis syndrome (BSS) and activated blood circulation of traditional Chinese medicine (TCM) is one of the most active fields where the integration of TCM and western medicine in China has been successful. Activated blood circulation herbs (ABC herbs) of Chinese medicine are often used in the treatment of BSS. Most ABC herbs have antiplatelet and anti-atherosclerosis activity, but knowledge about their targets is lacking. Coronary heart disease (CHD), BSS, and platelet activation are closely related. By screening and identifying activated platelet proteins that are differentially expressed in BSS of CHD, platelet proteomics has helped researchers interpret the antiplatelet mechanism of action of ABC herbs and provided many potential biomarkers for BSS that could be used to evaluate the clinical curative effect of new antiplatelet drugs. In this article the progress of platelet proteomics and its advanced application for research of BSS and ABC herbs of Chinese medicine are reviewed.

  15. 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 raspberry and by 38-55% for dewberry, P 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.

  16. Clinical and blood bank factors in the management of platelet refractoriness and alloimmunization.

    Science.gov (United States)

    Friedberg, R C; Donnelly, S F; Boyd, J C; Gray, L S; Mintz, P D

    1993-06-15

    Numerous independent and interdependent factors are involved in the posttransfusion platelet response. Factors such as ABO match and platelet age are related to circumstances potentially under the control of the blood bank physician and therefore may permit circumvention by an active transfusion service. On the other hand, factors such as fever or sepsis may be unavoidable, being related more to the individual patient or clinical condition. To evaluate which factors could be circumvented, we prospectively followed the 1-hour corrected count increments (CCIs) for 962 single-donor apheresis platelet transfusions to 71 refractory hematologic oncology inpatients, with concomitant recording of implicated factors. Stepwise regression analysis allowed for determination of which concurrent and confounding clinical-, patient-, and blood bank-related factors significantly affected the CCIs. Although many implicated factors proved to be independently associated with an increased or decreased CCI, we found that no single variable consistently explained the CCI variation across the patient population. Each patient appeared sensitive to one or a few particular factors, but because of marked intraindividual variation, it was not possible to identify a priori which factors were important for a given patient. The single exception was a solid-phase red blood cell adherence assay used to cross-match platelets, but only for alloimmunized patients. We also evaluated the utility of requesting HLA-matched platelets from the local suppliers and maintained a clear distinction between platelets simply ordered as HLA matched and actually HLA-identical platelets. Accounting for the confounding clinical-, patient-, and blood bank-related factors, the cross-match assay was a better predictor of an adequate CCI than ordering platelets as HLA matched.

  17. 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...

  18. 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

  19. Platelet transfusions in platelet consumptive disorders are associated with arterial thrombosis and in-hospital mortality.

    Science.gov (United States)

    Goel, Ruchika; Ness, Paul M; Takemoto, Clifford M; Krishnamurti, Lakshmanan; King, Karen E; Tobian, Aaron A R

    2015-02-26

    While platelets are primary mediators of hemostasis, there is emerging evidence to show that they may also mediate pathologic thrombogenesis. Little data are available on risks and benefits associated with platelet transfusions in thrombotic thrombocytopenic purpura (TTP), heparin-induced thrombocytopenia (HIT) and immune thrombocytopenic purpura (ITP). This study utilized the Nationwide Inpatient Sample to evaluate the current in-hospital platelet transfusion practices and their association with arterial/venous thrombosis, acute myocardial infarction (AMI), stroke, and in-hospital mortality over 5 years (2007-2011). Age and gender-adjusted odds ratios (adjOR) associated with platelet transfusions were calculated. There were 10 624 hospitalizations with TTP; 6332 with HIT and 79 980 with ITP. Platelet transfusions were reported in 10.1% TTP, 7.1% HIT, and 25.8% ITP admissions. Platelet transfusions in TTP were associated with higher odds of arterial thrombosis (adjOR = 5.8, 95%CI = 1.3-26.6), AMI (adjOR = 2.0, 95%CI = 1.2-3.3) and mortality (adjOR = 2.0,95%CI = 1.3-3.0), but not venous thrombosis. Platelet transfusions in HIT were associated with higher odds of arterial thrombosis (adjOR = 3.4, 95%CI = 1.2-9.5) and mortality (adjOR = 5.2, 95%CI = 2.6-10.5) but not venous thrombosis. Except for AMI, all relationships remained significant after adjusting for clinical severity and acuity. No associations were significant for ITP. Platelet transfusions are associated with higher odds of arterial thrombosis and mortality among TTP and HIT patients.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. PLATELET-LEUKOCYTE INTERACTIONS : MULTIPLE LINKS BETWEEN INFLAMMATION , BLOOD COAGULATION AND VASCULAR RISK

    Directory of Open Access Journals (Sweden)

    Chiara Cerletti

    2010-08-01

    Full Text Available The aim of this review is to summarize the contribution of platelets and leukocytes and their interactions in inflammation and blood coagulation and its possible relevance in the pathogenesis of  thrombosis. There is some evidence of an association between infection/inflammation and thrombosis. This is likely a bidirectional relationship. The presence of a thrombus may serve as a nidus of infection. Vascular injury indeed promotes platelet and leukocyte activation and thrombus formation and the thrombus and its components facilitate adherence of bacteria to the vessel wall. Alternatively, an infection and the associated inflammation can trigger platelet and leukocyte activation and thrombus formation. In either case platelets and leukocytes co-localize and interact in the area of vascular injury, at sites of inflammation and/or at sites of thrombosis. Following vascular injury, the subendothelial tissue, a thrombogenic surface, becomes available for interaction with these blood cells. Tissue factor, found not only in media and adventitia of the vascular wall, but also on activated platelets and leukocytes, triggers blood coagulation. Vascular-blood cell interactions, mediated by the release of preformed components of the endothelium, is modulated by both cell adhesion and production of soluble stimulatory or inhibitory molecules that alter cell function: adhesion molecules regulate cell-cell contact and facilitate the modulation of biochemical pathways relevant to inflammatory and/or thrombotic processes.

  6. Platelet concentrates for topical use: bedside device and blood transfusion technology. Quality and versatility.

    Science.gov (United States)

    Borzini, Piero; Balbo, Valeria; Mazzucco, Laura

    2012-06-01

    More or less after a decade of experimental and pioneering manual procedures to prepare platelet-rich plasma (PRP) for topical use, several portable and bedside devices were made available to prepare the PRP at the point-of-care. This technical opportunity increased the number of patients who got access to the treatment with autologous PRP and PRP-gel. Since topical treatment of tissue with PRP and PRP-gel was restricted to autologous preparation, blood transfusion centers that professionally prepare donor-derived platelet concentrates were not able to cover the overwhelming request for autologous PRP supply. Principally for logistic and organization reasons blood transfusion centers usually fail the challenge of prompt delivery of PRP to the physician over large territory. Nevertheless the blood bank production of platelet concentrates is associated with high standardization and quality controls not achievable from bedside and portable devices. Furthermore it easy to demonstrate that high-volume blood bank-produced platelet concentrates are less expensive than low-volume PRP produced by portable and bedside devices. Taking also in consideration the ever-increasing safety of the blood components, the relationship between bedside device-produced and blood-bank-produced PRP might be reconsidered. Here we discuss this topic concluding that the variety of sources of PRP production is an opportunity for versatility and that, ultimately, versatility is an opportunity for the patient's care.

  7. 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.

  8. 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.

  9. 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...

  10. Blood platelet production with breaks : optimization by SDP and simulation

    NARCIS (Netherlands)

    Haijema, Rene; van Dijk, Nico; van der Wal, Jan; Sibinga, Cees Smit

    2009-01-01

    The production and inventory management of blood products at blood banks and hospitals is it problem of general human interest. As a shortage may put lives at risk, shortages are to be kept to a minimum. As the supply is voluntary and costly, any spill of unused blood (products) is also to be minimi

  11. 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;

    2011-01-01

    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 com...

  12. 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

  13. 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 ...

  14. Physiopathology of blood platelets and development of platelets substitutes. Progress report, August 1, 1976--October 31, 1977. [/sup 51/Cr

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, M G

    1977-07-31

    Progress is reported on the following research projects: the effect of estrogen on platelet aggregability and thrombus formation; the antithrombotic effect of platelet inhibiting agents in a bench model of artificial kidney; the arrest of hemorrhage in severely alloimmunized thrombocytopenic patients; and in vivo elution of /sup 51/Cr from labeled platelets induced by antibody. (HLW)

  15. Platelets and infection — an emerging role of platelets in viral infection

    Directory of Open Access Journals (Sweden)

    Alice eAssinger

    2014-12-01

    Full Text Available Platelets are anucleate blood cells that play a crucial role in the maintenance of hemostasis. While platelet activation and elevated platelet counts (thrombocytosis are associated with increased risk of thrombotic complications, low platelet counts (thrombocytopenia and several platelet function disorders increase the risk of bleeding. Over the last years more and more evidence has emerged that platelets and their activation state can also modulate innate and adaptive immune responses and low platelet counts have been identified as a surrogate marker for poor prognosis in septic patients.Viral infections often coincide with platelet activation. Host inflammatory responses result in the release of platelet activating mediators and a pro-oxidative and pro-coagulant environment, which favours platelet activation. However, viruses can also directly interact with platelets and megakaryocytes and modulate their function. Furthermore, platelets can be activated by viral antigen-antibody complexes and in response to some viruses B-lymphocytes also generate anti-platelet antibodies.All these processes contributing to platelet activation result in increased platelet consumption and removal and often lead to thrombocytopenia, which is frequently observed during viral infection. However, virus-induced platelet activation does not only modulate platelet count, but also shapes immune responses. Platelets and their released products have been reported to directly and indirectly suppress infection and to support virus persistence in response to certain viruses, making platelets a double-edged sword during viral infections. This review aims to summarize the current knowledge on platelet interaction with different types of viruses, the viral impact on platelet activation and platelet-mediated modulations of innate and adaptive immune responses.

  16. Platelets and infection - an emerging role of platelets in viral infection.

    Science.gov (United States)

    Assinger, Alice

    2014-01-01

    Platelets are anucleate blood cells that play a crucial role in the maintenance of hemostasis. While platelet activation and elevated platelet counts (thrombocytosis) are associated with increased risk of thrombotic complications, low platelet counts (thrombocytopenia) and several platelet function disorders increase the risk of bleeding. Over the last years, more and more evidence has emerged that platelets and their activation state can also modulate innate and adaptive immune responses and low platelet counts have been identified as a surrogate marker for poor prognosis in septic patients. Viral infections often coincide with platelet activation. Host inflammatory responses result in the release of platelet activating mediators and a pro-oxidative and pro-coagulant environment, which favors platelet activation. However, viruses can also directly interact with platelets and megakaryocytes and modulate their function. Furthermore, platelets can be activated by viral antigen-antibody complexes and in response to some viruses B-lymphocytes also generate anti-platelet antibodies. All these processes contributing to platelet activation result in increased platelet consumption and removal and often lead to thrombocytopenia, which is frequently observed during viral infection. However, virus-induced platelet activation does not only modulate platelet count but also shape immune responses. Platelets and their released products have been reported to directly and indirectly suppress infection and to support virus persistence in response to certain viruses, making platelets a double-edged sword during viral infections. This review aims to summarize the current knowledge on platelet interaction with different types of viruses, the viral impact on platelet activation, and platelet-mediated modulations of innate and adaptive immune responses.

  17. Manipulation of oxygenation and flow-induced shear stress can increase the in vitro yield of platelets from cord blood.

    Science.gov (United States)

    Lasky, Larry C; Sullenbarger, Brent

    2011-11-01

    A method to produce clinically useful platelets in vitro would help overcome the frequent shortages, donor deferrals, disease transmission, and alloimmunization with volunteer donor-derived platelets. Using CD34 positively selected cord blood cells, we investigated ways to increase platelet quality and yield in a three-dimensional modular perfusion bioreactor system. We found a two- to threefold increase in platelet numbers produced only when the early phases of the culture process were carried out at 5% oxygen, versus when 20% oxygen was used throughout the culture period (pplatelets increased two- to threefold (pplatelet production from proplatelets. The use of altered oxygen levels and cross flow enhanced platelet numbers and quality, and will contribute to eventual in vitro platelet production for clinical use.

  18. Platelets promote bacterial dissemination in a mouse model of streptococcal sepsis.

    Science.gov (United States)

    Kahn, Fredrik; Hurley, Sinead; Shannon, Oonagh

    2013-01-01

    Platelets have been reported to contribute to inflammation and inflammatory disorders. In the present study, we demonstrate that platelets contribute to the acute response to bacterial infection in a mouse model of invasive Streptococcus pyogenes infection. Thrombocytopenia occurred rapidly in infected animals and this was associated with platelet activation, formation of platelet-neutrophil complexes and neutrophil activation. In order to assess the role of platelets during infection, platelets were depleted prior to infection. Platelet-depleted animals had significantly decreased platelet-neutrophil complex formation and neutrophil activation in response to infection. Importantly, significantly fewer bacteria disseminated to the blood, lungs, and spleen of platelet-depleted animals. Platelet-depleted animals did not decrease as significantly in weight as the infected control animals. The results demonstrate a previously unappreciated role for platelets during the pathophysiological response to infection, whereby S. pyogenes bacteria bind to platelets and platelets facilitate bacterial dissemination.

  19. Nucleation of platelets with blood-borne pathogens on Kupffer cells precedes other innate immunity and contributes to bacterial clearance.

    Science.gov (United States)

    Wong, Connie H Y; Jenne, Craig N; Petri, Björn; Chrobok, Navina L; Kubes, Paul

    2013-08-01

    Through the use of intravital imaging of the liver, we demonstrate a collaborative role for platelets with Kupffer cells (KCs) in eradicating blood-borne bacterial infection. Under basal conditions, platelets, via the platelet-adhesion receptor GPIb, formed transient 'touch-and-go' interactions with von Willebrand factor (vWF) constitutively expressed on KCs. Bacteria such as Bacillus cereus and methicillin-resistant Staphylococcus aureus (MRSA) were rapidly caught by KCs and triggered platelets to switch from 'touch-and-go' adhesion to sustained GPIIb-mediated adhesion on the KC surface to encase the bacterium. Infected GPIbα-deficient mice had more endothelial and KC damage than did their wild-type counterparts, which led to more fluid leakage, substantial polycythemia and rapid mortality. Our study identifies a previously unknown surveillance mechanism by which platelets survey macrophages that rapidly converts to a critical host response to blood-borne bacteria.

  20. 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.

  1. 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

  2. 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

  3. Psychobiology of borderline personality traits related to subtypes of eating disorders: a study of platelet MAO activity.

    Science.gov (United States)

    Díaz-Marsá, Marina; Carrasco, Jose L; de Anta, Laura; Molina, Rosa; Sáiz, Jerónimo; Cesar, Jesus; López-Ibor, Juan J

    2011-12-30

    Increased and decreased levers of platelet monoamine oxidase (MAO) activity have been reported in patients with eating disorders, indicating abnormalities of the serotonin turnover. However, whether these findings are related to eating disorders or are rather reflecting the pathophysiology of borderline personality traits in these patients is still unknown. Platelet MAO activity and comorbid personality disorders were investigated in 72 patients with different subtypes of eating disorders (ED) and in a group of 28 healthy controls. ED patients comprised the following subtypes: 25 anorexia nervosa (AN) restrictive, 14 AN binge eating-purging (AN b-p), 3 anorexia nervosa not otherwise specified (AN NOS) and 30 bulimia nervosa (BN). Personality disorders and traits were assessed with the Structured Interview for Personality Disorders (SCID-II), the Zanarini Rating Scale for Borderline Personality Disorder, and the Barrat Impulsiveness Scale. Platelet MAO activity was significantly lower in ED patients with comorbid borderline personality disorder (BPD) than in ED without Borderline personality disorder (BDP). Platelet MAO activity was significantly and inversely correlated with the number and severity of BPD clinical features. In the subsample of patients with binge eating-purging symptoms (AN b-p, AN NOS and BN), platelet MAO activity was significantly lower in binge-purge patients with comorbid BPD than in binge-purge patients without BPD. The whole group of eating disorders had a significantly reduced lever of platelet MAO activity compared with the control group. The results suggest that low platelet MAO activity might characterize eating disorders with comorbid borderline personality traits, reflecting greater serotonin dysfunction in these patients. The role of decreased platelet MAO as an endophenotype with specific clinical manifestations should be explored in future studies.

  4. 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

  5. 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.

  6. 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…

  7. 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.

  8. 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

  9. Effect of simvastatin combined amlodipine besylate on blood rheology and platelet activation in elderly patients with hypertension complicated with hyperlipemia

    Institute of Scientific and Technical Information of China (English)

    Ming-Zheng Jiang; Li Qiong; Hui Liu

    2016-01-01

    Objective:To investigate the effect of simvastatin combined amlodipine besylate on blood rheology and platelet activation in elderly patients with hypertension complicated with hyperlipemia.Methods: A total of 200 elderly patients with hypertension complicated with hyperlipemia were divided into hypertension group (n=64), hyperlipemia group (n=71) and combined (hypertension complicated with hyperlipemia) group (n=65). And alternate period health check-up 100 cases were selected as control group. The hypertension group was treated with amlodipine besylate monotherapy, hyperlipidemia group with simvastatin monotherapy, combined group received simvastatin combined with amlodipine besylate treatment, patients of three groups were treated for 12 weeks. Blood rheology and platelet activation before and after treatment were compared.Results: After treatment, blood pressure was significantly lower than that before treatment in hypertension and combined group (P<0.05), and the combined group reduced more significantly (P<0.05), blood fat was significantly lower than that before treatment in hyperlipemia and combined group (P<0.05), and combined group reduced more significantly (P<0.05); Before treatment, indexes of blood rheology (high shear whole blood viscosity, low shear whole blood viscosity, plasma viscosity, fibrinogen and platelet activation index (CD62p and CD63) of three groups were significantly higher than those in control group (P<0.05), and the combined group was increased more significantly than hypertension and hyperlipidemia group (P<0.05); After treatment, blood rheology (high shear whole blood viscosity, low shear whole blood viscosity, plasma viscosity, fibrinogen) and platelet activation index (CD62p and CD63) of hyperlipidemia group and combined group were significantly lower than before treatment (P<0.05), and the reduction combined group were more significant in amplitude (P<0.05).Conclusions: Simvastatin combined amlodipine besylate therapy can

  10. Proteomic methodological recommendations for studies involving human plasma, platelets, and peripheral blood mononuclear cells.

    Science.gov (United States)

    de Roos, Baukje; Duthie, Susan J; Polley, Abigael C J; Mulholland, Francis; Bouwman, Freek G; Heim, Carolin; Rucklidge, Garry J; Johnson, Ian T; Mariman, Edwin C; Daniel, Hannelore; Elliott, Ruan M

    2008-06-01

    This study was designed to develop, optimize and validate protocols for blood processing prior to proteomic analysis of plasma, platelets and peripheral blood mononuclear cells (PBMC) and to determine analytical variation of a single sample of depleted plasma, platelet and PBMC proteins within and between four laboratories each using their own standard operating protocols for 2D gel electrophoresis. Plasma depleted either using the Beckman Coulter IgY-12 proteome partitioning kit or the Amersham albumin and IgG depletion columns gave good quality gels, but reproducibility appeared better with the single-use immuno-affinity column. The use of the Millipore Filter Device for protein concentration gave a 16% ( p appears as a single abundant spot. The average within-laboratory coefficient of variation (CV) for each of the matched spots after automatic matching using either PDQuest or ProteomWeaver software ranged between 18 and 69% for depleted plasma proteins, between 21 and 55% for platelet proteins, and between 22 and 38% for PBMC proteins. Subsequent manual matching improved the CV with on average between 1 and 16%. The average between laboratory CV for each of the matched spots after automatic matching ranged between 4 and 54% for depleted plasma proteins, between 5 and 60% for platelet proteins, and between 18 and 70% for PBMC proteins. This variation must be considered when designing sufficiently powered studies that use proteomics tools for biomarker discovery. The use of tricine in the running buffer for the second dimension appears to enhance the resolution of proteins especially in the high molecular weight range.

  11. Compartmentalisation of cAMP-dependent signalling in blood platelets: The role of lipid rafts and actin polymerisation.

    Science.gov (United States)

    Raslan, Zaher; Naseem, Khalid M

    2015-01-01

    Prostacyclin (PGI2) inhibits blood platelets through the activation of membrane adenylyl cyclases (ACs) and cyclic adenosine 3',5'-monophosphate (cAMP)-mediated signalling. However, the molecular mechanism controlling cAMP signalling in blood platelet remains unclear, and in particular how individual isoforms of AC and protein kinase A (PKA) are coordinated to target distinct substrates in order to modulate platelet activation. In this study, we demonstrate that lipid rafts and the actin cytoskeleton may play a key role in regulating platelet responses to cAMP downstream of PGI2. Disruption of lipid rafts with methyl-beta-cyclodextrin (MβCD) increased platelet sensitivity to PGI2 and forskolin, a direct AC cyclase activator, resulting in greater inhibition of collagen-stimulated platelet aggregation. In contrast, platelet inhibition by the direct activator of PKA, 8-CPT-6-Phe-cAMP was unaffected by MβCD treatment. Consistent with the functional data, lipid raft disruption increased PGI2-stimulated cAMP formation and proximal PKA-mediated signalling events. Platelet inhibition, cAMP formation and phosphorylation of PKA substrates in response to PGI2 were also increased in the presence of cytochalasin D, indicating a role for actin cytoskeleton in signalling in response to PGI2. A potential role for lipid rafts in cAMP signalling is strengthened by our finding that a pool of ACV/VI and PKA was partitioned into lipid rafts. Our data demonstrate partial compartmentalisation of cAMP signalling machinery in platelets, where lipid rafts and the actin cytoskeleton regulate the inhibitory effects induced by PGI2. The increased platelet sensitivity to cAMP-elevating agents signalling upon raft and cytoskeleton disruption suggests that these compartments act to restrain basal cAMP signalling.

  12. 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

  13. 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

  14. The effect of protein corona composition on the interaction of carbon nanotubes with human blood platelets.

    Science.gov (United States)

    De Paoli, Silvia H; Diduch, Lukas L; Tegegn, Tseday Z; Orecna, Martina; Strader, Michael B; Karnaukhova, Elena; Bonevich, John E; Holada, Karel; Simak, Jan

    2014-08-01

    Carbon nanotubes (CNT) are one of the most promising nanomaterials for use in medicine. The blood biocompatibility of CNT is a critical safety issue. In the bloodstream, proteins bind to CNT through non-covalent interactions to form a protein corona, thereby largely defining the biological properties of the CNT. Here, we characterize the interactions of carboxylated-multiwalled carbon nanotubes (CNTCOOH) with common human proteins and investigate the effect of the different protein coronas on the interaction of CNTCOOH with human blood platelets (PLT). Molecular modeling and different photophysical techniques were employed to characterize the binding of albumin (HSA), fibrinogen (FBG), γ-globulins (IgG) and histone H1 (H1) on CNTCOOH. We found that the identity of protein forming the corona greatly affects the outcome of CNTCOOH's interaction with blood PLT. Bare CNTCOOH-induced PLT aggregation and the release of platelet membrane microparticles (PMP). HSA corona attenuated the PLT aggregating activity of CNTCOOH, while FBG caused the agglomeration of CNTCOOH nanomaterial, thereby diminishing the effect of CNTCOOH on PLT. In contrast, the IgG corona caused PLT fragmentation, and the H1 corona induced a strong PLT aggregation, thus potentiating the release of PMP.

  15. 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, ...

  16. Adhesion of blood platelets under flow to wettability gradient polyethylene surfaces made in a shielded gas plasma

    NARCIS (Netherlands)

    Spijker, HT; Busscher, HJ; Graaff, R; van Oeveren, W; Bos, R.R.M.

    2002-01-01

    Adhesion and activation of platelets are important steps in the thrombosis of blood after contact with a biomaterial surface and are governed, in part, by the wettability of the surface. Since most implanted devices are in contact with blood under flow conditions, it is important to study the effect

  17. 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, ...

  18. 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...... excess occurrence of neurodegenerative disease occurred among recipients of blood from a subset of donors was also investigated. As a positive control, transmission of chronic hepatitis before and after implementation of hepatitis C virus screening was assessed. Results: Among included patients, 2.......9% received a transfusion from a donor diagnosed with one of the studied neurodegenerative diseases. No evidence of transmission of any of these diseases was found, regardless of approach. The hazard ratio for dementia in recipients of blood from donors with dementia versus recipients of blood from healthy...

  19. Activation-dependent surface expression of gC1qR/p33 on human blood platelets.

    Science.gov (United States)

    Peerschke, Ellinor I B; Murphy, Tara K; Ghebrehiwet, Berhane

    2003-02-01

    GC1qR/p33 (gC1qR) is expressed by a variety of somatic and cultured cells, including blood platelets. It interacts with several cellular, viral, bacterial, and plasma proteins, suggesting a potential role in thrombosis, inflammation, and infection. Considerable controversy has surrounded the surface membrane localization of gC1qR, however, since its cDNA sequence does not predict a traditional membrane-anchoring domain, and bears a typical mitochondrial targeting sequence. The present study examined gC1qR expression on resting and activated human blood platelets using flow cytometry and confocal microscopy with two monoclonal antibodies, 74.5.2 and 60.11, directed against gC1qR C-terminal amino acids 204-218, and N-terminal amino acids 76-93, respectively. Unstimulated platelets reacted minimally with either antibody. In contrast, platelet activation with TRAP, epinephrine, or ADP produced markedly increased gC1qR expression as reflected by 74.5.2 binding but not 60.11 binding. Platelet activation was verified using PAC-1 and anti CD 62 antibodies. Whereas PAC-1 binding to activated platelets could be reversed following platelet incubation with PGE1, 74.5.2 binding remained unchanged, suggesting the sustained expression of gC1qR following platelet stimulation. The data further demonstrate that detection of cell surface gC1qR may be dependent on antibody specificity. The ability of gC1qR to bind proteins involved in complement, coagulation, and kinin systems, as well as viral and bacterial pathogens including S. aureus protein A, supports the hypothesis that gC1qR expressed on activated platelets may contribute directly to thrombosis, inflammation, and endovascular infections.

  20. 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.

  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. 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

  3. 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...

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

    Institute of Scientific and Technical Information of China (English)

    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:A total of 102 patients undergoing valvular heart surgery (from October 2010 to June 2011) were divided into DDAVP group (n =52) and control group (n =50).A dose of DDAVP (0.3 μtg/kg) was administered to the patients intravenously when they were being re-warmed.At the same time,an equal volume of saline was given to the patients in the control group.PLT aggregation rate was measured with the AggRAM four-way PLT aggregation measurement instrument.The blood loss and transfusion,hemoglobin levels,PLT counts,and urine outputs at different time were recorded and compared.Results:The postoperative blood loss in the first 6 h was significantly reduced in DDAVP group (202 ± 119 ml vs.258 ± 143 ml,P =0.023).The incidence of fresh frozen plasma (FFP) transfusion was decreased postoperatively in DDAVP group (3.8% vs.12%,P =0.015).There was no significant difference in the PLT aggregation,urine volumes,red blood cell transfusions and blood loss after 24 h between two groups.Conclusions:A single dose of DDAVP can reduce the first 6 h blood loss and FFP transfusion postoperatively in patients undergoing valvular heart surgery,but has no effect on PLT aggregation.

  5. 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.

  6. 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

  7. Epinephrine enhances platelet-neutrophil adhesion in whole blood in vitro.

    NARCIS (Netherlands)

    Horn, N.A.; Anastase, D.M.; Hecker, K.E.; Baumert, J.H.; Robitzsch, T.; Rossaint, R.

    2005-01-01

    Previous studies showed that alpha- or beta-adrenoceptor stimulation by catecholamines influenced neutrophil function, cytokine liberation, and platelet aggregability. We investigated whether adrenergic stimulation with epinephrine also alters platelet-neutrophil adhesion. This might be of specific

  8. 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

  9. Platelet-active substances in the venom of Bothrops moojeni snake-a novel evaluation method using whole blood aggregometry.

    Science.gov (United States)

    Demler, Christine; Bühler, Beatrice; Menin, Laure; Stöcklin, Reto; Wilmer, Marianne; Ernst, Beat; Perchuc, Anna Maria

    2010-01-01

    The objective of the present study was an investigation of the crude Bothrops moojeni venom, aiming at the identification of new compounds with platelet-activating or -inhibiting activity. The venom was separated by gel filtration chromatography into 18 fractions, which were tested by means of whole blood aggregometry for their activities affecting the aggregation of blood platelets. In order to eliminate interferences caused by prothrombin activators or thrombin like-enzymes, which are frequently present in snake venoms, a test method for screening protein mixtures was developed. To avoid clotting of the blood samples, the thrombin inhibitor hirudin and the synthetic inhibitor of fibrin polymerization Pefabloc FG were applied. In the present study, a platelet aggregation activator with an activity resembling thrombocytin from B. atrox was identified in one of the examined venom fractions. In addition, a platelet antagonist-most likely a disintegrin-with broad inhibitory activity against aggregation triggered by collagen, adenosine diphosphate and thrombin receptor activating peptide, was identified. PMID:19938887

  10. 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

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

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    Sartaj Bhat

    2015-07-01

    Full Text Available 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. Among 560 neonates, 80/560 (14.28% had Culture positive sepsis. Out of 80 blood culture positive neonates 73 were term neonates and 7 were near term. Gram positive sepsis occurred in 21/80 (26.25%, gram negative sepsis in 54/80 (67.5%, and fungal sepsis in 5/80 (6.25%. Incidence of thrombocytopenia in Gram negative sepsis was (35/54 64.81%, in gram positive sepsis (15/21 71.41% and in fungal sepsis was (3/5 60%. Mean platelet count at the onset of sepsis in all the patients was 123287.5±49428.68. The mean duration of thrombocytopenia in gram positive sepsis was 4.66 ±2.6 days, in gram negative sepsis 4.39 ± 2.22 days and in fungal sepsis 5.2±1.3 days. MPV at the time of onset of sepsis (MPV was high in gram positive sepsis than in gram negative sepsis (11.57±0.88 Vs 11.29 ± 0.76. The MPV of thrombocytopenic neonates was significantly higher than that of non-thrombocytopenic neonates (p < 0.01.

  12. Increased platelet oxidative metabolism, blood oxidative stress and neopterin levels after ultra-endurance exercise.

    Science.gov (United States)

    de Lucas, Ricardo Dantas; Caputo, Fabrizio; Mendes de Souza, Kristopher; Sigwalt, André Roberto; Ghisoni, Karina; Lock Silveira, Paulo Cesar; Remor, Aline Pertile; da Luz Scheffer, Débora; Guglielmo, Luiz Guilherme Antonacci; Latini, Alexandra

    2014-01-01

    The purpose of the present investigation was to identify muscle damage, inflammatory response and oxidative stress blood markers in athletes undertaking the ultra-endurance MultiSport Brazil race. Eleven well-trained male athletes (34.3 ± 3.1 years, 74.0 ± 7.6 kg; 172.2 ± 5.1 cm) participated in the study and performed the race, which consisted of about 90 km of alternating off-road running, mountain biking and kayaking. Twelve hours before and up to 15 minutes after the race a 10 mL blood sample was drawn in order to measure the following parameters: lactate dehydrogenase and creatine kinase activities, lipid peroxidation, catalase activity, protein carbonylation, respiratory chain complexes I, II and IV activities, oxygen consumption and neopterin concentrations. After the race, plasma lactate dehydrogenase and creatine kinase activities were significantly increased. Erythrocyte TBA-RS levels and plasma protein carbonylation were markedly augmented in post-race samples. Additionally, mitochondrial complex II activity and oxygen consumption in post-race platelet-rich plasma were also increased. These altered biochemical parameters were accompanied by increased plasma neopterin levels. The ultra-endurance event provoked systemic inflammation (increased neopterin) accompanied by marked oxidative stress, likely by increasing oxidative metabolism (increased oxidative mitochondrial function). This might be advantageous during prolonged exercise, mainly for efficient substrate oxidation at the mitochondrial level, even when tissue damage is induced.

  13. 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

  14. Genetically engineered blood pharming: generation of HLA-universal platelets derived from CD34+ progenitor cells.

    Science.gov (United States)

    Figueiredo, Constança; Blaszczyk, Rainer

    2014-01-01

    Blood pharming is a recently designed concept to enable in vitro production of blood cells that are safe, effective and readily available. This approach represents an alternative to blood donation and may contribute to overcome the shortage of blood products. However, the high variability of the human leukocyte antigen (HLA) loci remains a major hurdle to the application of off-the-shelf blood products. Refractoriness to platelet (PLT) transfusion caused by alloimmunization against HLA class I antigens constitutes a relevant clinical problem. Thus, it would be desirable to generate PLT units devoid of HLA antigens. To reduce the immunogenicity of cell-based therapeutics, we have permanently reduced HLA class I expression using an RNA interference strategy. Furthermore, we demonstrated that the generation of HLA class I-silenced (HLA-universal) PLTs from CD34+ progenitor cells using an shRNA targeting β2-microglobulin transcripts is feasible. CD34+ progenitor cells derived from G-CSF mobilised donors were transduced with a lentiviral vector encoding for the β2-microglobulin-specific shRNA and differentiated into PLTs using a liquid culture system. The functionality of HLA-silenced PLTs and their ability to escape HLA antibody-mediated cytotoxicity were evaluated in vitro and in vivo. Platelet activation in response to ADP and thrombin were assessed in vitro. The immune-evasion capability of HLA-universal megakaryocytes (MKs) and PLTs was tested in lymphocytotoxicity assays using anti-HLA antibodies. To assess the functionality of HLA-universal PLTs in vivo, HLA-silenced MKs were infused into NOD/SCID/IL-2Rγc(-/-) mice with or without anti-HLA antibodies. PLT generation was evaluated by flow cytometry using anti-CD42a and CD61 antibodies. HLA-universal PLTs demonstrated to be functionally similar to blood-derived PLTs. Lymphocytotoxicity assays showed that HLA-silencing efficiently protects MKs against HLA antibody-mediated complement-dependent cytotoxicity. 80

  15. Genetically engineered blood pharming: generation of HLA-universal platelets derived from CD34+ progenitor cells.

    Science.gov (United States)

    Figueiredo, Constança; Blaszczyk, Rainer

    2014-01-01

    Blood pharming is a recently designed concept to enable in vitro production of blood cells that are safe, effective and readily available. This approach represents an alternative to blood donation and may contribute to overcome the shortage of blood products. However, the high variability of the human leukocyte antigen (HLA) loci remains a major hurdle to the application of off-the-shelf blood products. Refractoriness to platelet (PLT) transfusion caused by alloimmunization against HLA class I antigens constitutes a relevant clinical problem. Thus, it would be desirable to generate PLT units devoid of HLA antigens. To reduce the immunogenicity of cell-based therapeutics, we have permanently reduced HLA class I expression using an RNA interference strategy. Furthermore, we demonstrated that the generation of HLA class I-silenced (HLA-universal) PLTs from CD34+ progenitor cells using an shRNA targeting β2-microglobulin transcripts is feasible. CD34+ progenitor cells derived from G-CSF mobilised donors were transduced with a lentiviral vector encoding for the β2-microglobulin-specific shRNA and differentiated into PLTs using a liquid culture system. The functionality of HLA-silenced PLTs and their ability to escape HLA antibody-mediated cytotoxicity were evaluated in vitro and in vivo. Platelet activation in response to ADP and thrombin were assessed in vitro. The immune-evasion capability of HLA-universal megakaryocytes (MKs) and PLTs was tested in lymphocytotoxicity assays using anti-HLA antibodies. To assess the functionality of HLA-universal PLTs in vivo, HLA-silenced MKs were infused into NOD/SCID/IL-2Rγc(-/-) mice with or without anti-HLA antibodies. PLT generation was evaluated by flow cytometry using anti-CD42a and CD61 antibodies. HLA-universal PLTs demonstrated to be functionally similar to blood-derived PLTs. Lymphocytotoxicity assays showed that HLA-silencing efficiently protects MKs against HLA antibody-mediated complement-dependent cytotoxicity. 80

  16. 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.

  17. 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.

  18. 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.

  19. Platelet lipidomic.

    Science.gov (United States)

    Dolegowska, B; Lubkowska, A; De Girolamo, L

    2012-01-01

    Lipids account for 16-19 percent dry platelet matter and includes 65 percent phospholipids, 25 percent neutral lipids and about 8 percent glycosphingolipids. The cell membrane that surrounds platelets is a bilayer that contains different types phospholipids symmetrically distributed in resting platelets, such as phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylcholine, and sphingomyelin. The collapse of lipid asymmetry is exposure of phosphatidylserine in the external leaflet of the plasma bilayer, where it is known to serve at least two major functions: providing a platform for development of the blood coagulation cascade and presenting the signal that induces phagocytosis of apoptotic cells. During activation, this asymmetrical distribution becomes disrupted, and PS and PE become exposed on the cell surface. The transbilayer movement of phosphatidylserine is responsible for the platelet procoagulant activity. Exposure of phosphatidylserine is a flag for macrophage recognition and clearance from the circulation. Platelets, stored at room temperature for transfusion for more than 5 days, undergo changes collectively known as platelet storage lesions. Thus, the platelet lipid composition and its possible modifications over time are crucial for efficacy of platelet rich plasma therapy. Moreover, a number of substances derived from lipids are contained into platelets. Eicosanoids are lipid signaling mediators generated by the action of lipoxygenase and include prostaglandins, thromboxane A2, 12-hydroxyeicosatetraenoic acid. Isoprostanes have a chemical structure similar to this of prostanoids, but are differently produced into the particle, and are ligands for prostaglandins receptors, exhibiting biological activity like thromboxane A2. Endocannabinoids are derivatives from arachidonic acid which could reduce local pain. Phospholipids growth factors (sphingolipids, lysophosphatidic acid, platelet-activating factor) are involved in tissue

  20. Dopamine concentration in blood platelets is elevated in patients with head and neck paragangliomas

    NARCIS (Netherlands)

    Osinga, Thamara E.; van der Horst-Schrivers, Anouk N A; van Faassen, Martijn; Kerstens, Michiel N; Dullaart, Robin P F; Peters, Marloes A M; van der Laan, Bernard F A M; de Bock, Geertruida H; Links, Thera P; Kema, Ido P

    2015-01-01

    BACKGROUND: Plasma 3-methoxytyramine (3-MT), a metabolite of dopamine, is elevated in up to 28% of patients with head and neck paragangliomas (HNPGLs). As free dopamine is incorporated in circulating platelets, we determined dopamine concentration in platelets in patients with a HNPGL. METHODS: A si

  1. 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...

  2. 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.

  3. 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

  4. Clinical investigation of oral findings in inherited disorders of platelet function

    Directory of Open Access Journals (Sweden)

    Müjgan Güngör Hatipoğlu

    2011-12-01

    Full Text Available Objective: Bleeding disorders are a very important health problem due to the associated high risk of hemorrhage during dental procedures. The present study aimed to investigate oral manifestations of inherited disorders of platelet function (IDPF. Materials and Methods: The study included 20 IDPF patients (mean age: 31.90±10.71 years and 40 healthy controls (mean age: 31.63±9.07 years. Tooth brushing habits, level of education, and clinical index scores (Simplified Oral Hygiene Index [OHI-S], Decayed Missing Filled Teeth Index [DMFT] index, probing depth [PD] index, Gingival Bleeding Index [GBI], and Community Periodontal Index [CPI] were recorded. Results: There weren’t any significant differences between the 2 groups with respect to tooth brushing habit, level of education level, OHI-S, DMFT index, or CPI (p>0.05, whereas significant differences in PD index and GBI were observed between the groups (p<0.05.Conclusion: The present study’s findings show that IDPF has a negative effect on periodontal tissues.

  5. 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.

  6. Metalloproteases Affecting Blood Coagulation, Fibrinolysis and Platelet Aggregation from Snake Venoms: Definition and Nomenclature of Interaction Sites

    Science.gov (United States)

    Kini, R. Manjunatha; Koh, Cho Yeow

    2016-01-01

    Snake venom metalloproteases, in addition to their contribution to the digestion of the prey, affect various physiological functions by cleaving specific proteins. They exhibit their activities through activation of zymogens of coagulation factors, and precursors of integrins or receptors. Based on their structure–function relationships and mechanism of action, we have defined classification and nomenclature of functional sites of proteases. These metalloproteases are useful as research tools and in diagnosis and treatment of various thrombotic and hemostatic conditions. They also contribute to our understanding of molecular details in the activation of specific factors involved in coagulation, platelet aggregation and matrix biology. This review provides a ready reference for metalloproteases that interfere in blood coagulation, fibrinolysis and platelet aggregation. PMID:27690102

  7. Preparation, quality criteria, and properties of human blood platelet lysate supplements for ex vivo stem cell expansion.

    Science.gov (United States)

    Shih, Daniel Tzu-Bi; Burnouf, Thierry

    2015-01-25

    Most clinical applications of human multipotent mesenchymal stromal cells (MSCs) for cell therapy, tissue engineering, regenerative medicine, and treatment of immune and inflammatory diseases require a phase of isolation and ex vivo expansion allowing a clinically meaningful cell number to be reached. Conditions used for cell isolation and expansion should meet strict quality and safety requirements. This is particularly true for the growth medium used for MSC isolation and expansion. Basal growth media used for MSC expansion are supplemented with multiple nutrients and growth factors. Fetal bovine serum (FBS) has long been the gold standard medium supplement for laboratory-scale MSC culture. However, FBS has a poorly characterized composition and poses risk factors, as it may be a source of xenogenic antigens and zoonotic infections. FBS has therefore become undesirable as a growth medium supplement for isolating and expanding MSCs for human therapy protocols. In recent years, human blood materials, and most particularly lysates and releasates of platelet concentrates have emerged as efficient medium supplements for isolating and expanding MSCs from various origins. This review analyzes the advantages and limits of using human platelet materials as medium supplements for MSC isolation and expansion. We present the modes of production of allogeneic and autologous platelet concentrates, measures taken to ensure optimal pathogen safety profiles, and methods of preparing PLs for MSC expansion. We also discuss the supply of such blood preparations. Produced under optimal conditions of standardization and safety, human platelet materials can become the future 'gold standard' supplement for ex vivo production of MSCs for translational medicine and cell therapy applications.

  8. 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

  9. Platelets, immune-mediated thrombocytopenias, and fetal hemorrhage.

    Science.gov (United States)

    Xu, Xiaohong Ruby; Gallant, Reid C; Ni, Heyu

    2016-05-01

    Platelets are small versatile blood cells generated from megakaryocytes in the bone marrow and cleared in the reticuloendothelial system. Platelet accumulation (adhesion and aggregation) at the site of injury has been considered the first wave of hemostasis. Interestingly, although fibrinogen and von Willebrand factor (VWF) are documented to be essential for hemostasis, fibrinogen/VWF-independent platelet aggregation and thrombosis still occur. Following platelet activation and phosphatidylserine expression, platelets also contribute to cell-based thrombin generation and blood coagulation - the second wave of hemostasis. Most recently, deposition of fibronectin and other plasma proteins onto the injured vessel wall was identified as a "protein wave" of hemostasis, in which platelets may release their granule proteins and thus also contribute to this very early hemostatic event. Due to the central roles of platelets in hemostasis, excessive platelet clearance may lead to bleeding disorders as observed in auto- and alloimmune-mediated thrombocytopenias. In this review, we will introduce several new pathways of thrombosis and hemostasis as well as antibody Fc-independent platelet clearance, which may play an important role in immune-mediated thrombocytopenias. We will also discuss the roles of platelets in fetal hemostasis that may deserve further investigation. PMID:27207432

  10. 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

  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; Freson, Kathleen; Ouwehand, Willem H.; Turro, Ernest

    2016-01-01

    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. 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

  13. 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.

  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. Platelet Activation in Human Immunodeficiency Virus Type-1 Patients Is Not Altered with Cocaine Abuse.

    Directory of Open Access Journals (Sweden)

    Michelle Kiebala

    Full Text Available Recent work has indicated that platelets, which are anucleate blood cells, significantly contribute to inflammatory disorders. Importantly, platelets also likely contribute to various inflammatory secondary disorders that are increasingly associated with Human Immunodeficiency Virus Type-1 (HIV infection including neurological impairments and cardiovascular complications. Indeed, HIV infection is often associated with increased levels of platelet activators. Additionally, cocaine, a drug commonly abused by HIV-infected individuals, leads to increased platelet activation in humans. Considering that orchestrated signaling mechanisms are essential for platelet activation, and that nuclear factor-kappa B (NF-κB inhibitors can alter platelet function, the role of NF-κB signaling in platelet activation during HIV infection warrants further investigation. Here we tested the hypothesis that inhibitory kappa B kinase complex (IKK activation would be central for platelet activation induced by HIV and cocaine. Whole blood from HIV-positive and HIV-negative individuals, with or without cocaine abuse was used to assess platelet activation via flow cytometry whereas IKK activation was analyzed by performing immunoblotting and in vitro kinase assays. We demonstrate that increased platelet activation in HIV patients, as measured by CD62P expression, is not altered with reported cocaine use. Furthermore, cocaine and HIV do not activate platelets in whole blood when treated ex vivo. Finally, HIV-induced platelet activation does not involve the NF-κB signaling intermediate, IKKβ. Platelet activation in HIV patients is not altered with cocaine abuse. These results support the notion that non-IKK targeting approaches will be better suited for the treatment of HIV-associated inflammatory disorders.

  17. 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…

  18. Inhibition of whole blood platelet-aggregation by compounds in garlic clove extracts and commercial garlic products.

    Science.gov (United States)

    Lawson, L D; Ransom, D K; Hughes, B G

    1992-01-15

    The inhibitory effects of adenosine and 16 quantitatively determined organosulfur compounds derived from garlic cloves or commercial garlic preparations on collagen stimulated in vitro platelet aggregation in whole blood were determined. An estimation of the anti-aggregatory activity of several brands of the major types of commercial garlic preparations was determined from the activities of the individual compounds present in each sample. In platelet rich plasma (PRP) most of the anti-aggregatory activity of garlic clove homogenates was due to adenosine; however, in whole blood neither adenosine nor the polar fraction had any effect and all of the anti-aggregatory activity was due to allicin and other thiosulfinates. Allicin was equally active in whole blood and PRP. Among brands there was a several-fold variation in content of the organosulfur compounds and activity for all types of garlic products tested. The best garlic powder tablets were equally as active as clove homogenates whereas steam-distilled oils were 35% as active and oil-macerates (due to low content) only 12% as active. A garlic product aged many months in aqueous alcohol had no activity. For steam-distilled oils, most of the activity was due to diallyl trisulfide. For the oil-macerates, most of the activity was due largely to the vinyl dithiins. Ajoene, an exclusive component of the oil-macerates, had highest specific activity of all the compounds tested but, because of its low concentration, had only 13% of the activity of diallyl trisulfide and 3% of the activity of allicin. Compounds which may be active in vivo are discussed. PMID:1579891

  19. 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...

  20. 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.

  1. Synergistic effects of high blood cholesterol and hypertension on leukocyte and platelet recruitment in the cerebral microcirculation.

    Science.gov (United States)

    Rodrigues, Stephen F; Almeida-Paula, Lidiana D; Granger, Daniel N

    2014-04-01

    Hypertension or hypercholesterolemia can induce a proinflammatory and prothrombogenic phenotype in the microcirculation of the brain; however, less is known about how the combination of these risk factors affects the vasculature. We recently reported that a moderate (60%) increase in plasma cholesterol blunts the recruitment of leukocytes and platelets in the cerebral microvessels elicited by hypertension. In this study, we examined whether larger increments in blood cholesterol (4-fold) exerts a similar modulating influence on the vasculature in the presence of hypertension. Apolipoprotein E-knockout mice with deoxycorticosterone acetate salt-induced hypertension were placed on a high-cholesterol diet and exhibited exaggerated leukocyte and platelet adhesion responses in cerebral microvessels. Intermittent feeding (every fourth day) with high-cholesterol diet yielded similar phenotypic changes in the vasculature. Once the mice were placed on high-cholesterol diet, 4 days on normal diet (ND) were needed to revert to a normal vascular phenotype. Angiotensin II type 1 receptors and reactive oxygen species seem to contribute to the vascular responses induced by hypercholesterolemia and hypertension. Our findings indicate that the combination of hypertension and large increases in plasma cholesterol concentration results in a severe, but reversible, inflammatory and thrombogenic phenotype in the cerebral microvasculature.

  2. Small for Gestational Age and Magnesium in Cord Blood Platelets: Intrauterine Magnesium Deficiency May Induce Metabolic Syndrome in Later Life

    Directory of Open Access Journals (Sweden)

    Junji Takaya

    2011-01-01

    Full Text Available Magnesium deficiency in pregnancy frequently occurs because of inadequate or low intake of magnesium. Magnesium deficiency during pregnancy can induce not only maternal and fetal nutritional problems, but also consequences that might last in offspring throughout life. Many epidemiological studies have disclosed that small for gestational age (SGA is associated with an increased risk of insulin resistance in adult life. We reported that intracellular magnesium of cord blood platelets is lower in SGA groups than that in appropriate for gestational age groups, suggesting that intrauterine magnesium deficiency may result in SGA. Taken together, intrauterine magnesium deficiency in the fetus may lead to or at least program insulin resistance after birth. In this review, we propose that intrauterine magnesium deficiency may induce metabolic syndrome in later life. We discuss the potential contribution of aberrant magnesium regulation to SGA and to the pathogenesis of metabolic syndrome.

  3. 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.

  4. 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...

  5. The treatment of neurodegenerative disorders using umbilical cord blood and menstrual blood-derived stem cells.

    Science.gov (United States)

    Sanberg, Paul R; Eve, David J; Willing, Alison E; Garbuzova-Davis, Svitlana; Tan, Jun; Sanberg, Cyndy D; Allickson, Julie G; Cruz, L Eduardo; Borlongan, Cesar V

    2011-01-01

    Stem cell transplantation is a potentially important means of treatment for a number of disorders. Two different stem cell populations of interest are mononuclear umbilical cord blood cells and menstrual blood-derived stem cells. These cells are relatively easy to obtain, appear to be pluripotent, and are immunologically immature. These cells, particularly umbilical cord blood cells, have been studied as either single or multiple injections in a number of animal models of neurodegenerative disorders with some degree of success, including stroke, Alzheimer's disease, amyotrophic lateral sclerosis, and Sanfilippo syndrome type B. Evidence of anti-inflammatory effects and secretion of specific cytokines and growth factors that promote cell survival, rather than cell replacement, have been detected in both transplanted cells.

  6. Sources of variability in platelet accumulation on type 1 fibrillar collagen in microfluidic flow assays.

    Directory of Open Access Journals (Sweden)

    Keith B Neeves

    Full Text Available Microfluidic flow assays (MFA that measure shear dependent platelet function have potential clinical applications in the diagnosis and treatment of bleeding and thrombotic disorders. As a step towards clinical application, the objective of this study was to measure how phenotypic and genetic factors, as well as experimental conditions, affect the variability of platelet accumulation on type 1 collagen within a MFA. Whole blood was perfused over type 1 fibrillar collagen at wall shear rates of 150, 300, 750 and 1500 s⁻¹ through four independent channels with a height of 50 µm and a width of 500 µm. The accumulation of platelets was characterized by the lag time to 1% platelet surface coverage (Lag(T, the rate of platelet accumulation (V(PLT, and platelet surface coverage (SC. A cohort of normal donors was tested and the results were correlated to plasma von Willebrand factor (VWF levels, platelet count, hematocrit, sex, and collagen receptors genotypes. VWF levels were the strongest determinant of platelet accumulation. VWF levels were positively correlated to V(PLT and SC at all wall shear rates. A longer Lag(T for platelet accumulation at arterial shear rates compared to venous shear rates was attributed to the time required for plasma proteins to adsorb to collagen. There was no association between platelet accumulation and hematocrit or platelet count. Individuals with the AG genotype of the GP6 gene had lower platelet accumulation than individuals with the AA genotype at 150 s⁻¹ and 300 s⁻¹. Recalcified blood collected into sodium citrate and corn trypsin inhibitor (CTI resulted in diminished platelet accumulation compared to CTI alone, suggesting that citrate irreversibly diminishes platelet function. This study the largest association study of MFA in healthy donors (n = 104 and will likely set up the basis for the determination of the normal range of platelet responses in this type of assay.

  7. 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

  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. Platelet alloimmunization after transfusion

    DEFF Research Database (Denmark)

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

    1997-01-01

    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...... who received a single series of blood transfusions. They received mostly saline-adenine-glucose+mannitol red blood cell components (poor in leukocytes and platelets) in connection with cardiac surgery. Platelet-specific antibodies were detected with the platelet ELISA and the monoclonal...... (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...

  10. 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

  11. 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

  12. Influence of acceleration voltage on scanning electron microscopy of human blood platelets.

    Science.gov (United States)

    Pretorius, E

    2010-03-01

    Scanning electron microscopy (SEM) is used to view a variety of surface structures, molecules, or nanoparticles of different materials, ranging from metals, dental and medical instruments, and chemistry (e.g. polymer analysis) to biological material. Traditionally, the operating conditions of the SEM are very important in the material sciences, particularly the acceleration voltage. However, in biological sciences, it is not typically seen as an important parameter. Acceleration voltage allows electrons to penetrate the sample; thus, the higher the acceleration voltage the more penetration into the sample will occur. As a result, ultrastructural information from deeper layers will interfere with the actual surface morphology that is seen. Therefore, ultimately, if acceleration voltage is lower, a better quality of the surface molecules and structures will be produced. However, in biological sciences, this is an area that is not well-documented. Typically, acceleration voltages of between 5 and 20 kV are used. This manuscript investigates the influence of acceleration voltages ranging from 5 kV to as low as 300 V, by studying surface ultrastructure of a human platelet aggregate. It is concluded that, especially at higher magnifications, much more surface detail is visible in biological samples when using an acceleration voltage between 2 kV and 300 V.

  13. Rheology Research of Red Blood Cell and Platelet in Elderly Patients During Perioperation%老年患者围术期红细胞、血小板流变性的研究

    Institute of Scientific and Technical Information of China (English)

    朱剑锋

    2002-01-01

    Objective To investigate the rheological changes of red blood cell and platelet and their clinical significant in elderlypatients. Methods Take preoperative and postoperative blood from the finger tip of 37 elderly patients and observe the clumping, fluidity,plastic of red blood cells and clumping of platelet with variable project microscope. Then calculate the intergral numbers and compare themwith that of adults. Results The numbers of the clumping, fluidity, plastic of red blood cells and clumping of platelet were increased afteroperation (P < 0.01 ). Compared to elderly patients, the clumping, fluidity, plastic of red blood cells and clumping of platelet in adultpatients were 1ow (P<0.05). There was no different rheology in two group before operation (P>0.05).Conclution There was distincttrouble of rhenlogy in patients during perioperation, especial in elderly patents.

  14. Activation of blood coagulation in autoimmune skin disorders.

    Science.gov (United States)

    Cugno, Massimo; Tedeschi, Alberto; Crosti, Carlo; Marzano, Angelo V

    2009-09-01

    The immune system and blood coagulation are simultaneously activated in several inflammatory systemic disorders, such as lupus erythematosus, rheumatoid arthritis and inflammatory bowel diseases. Proinflammatory cytokines, such as IL-6 and TNF-alpha, induce the expression of tissue factor, the main initiator of blood coagulation. Activated proteases of coagulation in turn act on protease-activated receptors, inducing the expression of various proinflammatory cytokines. This cross-talk between inflammation and coagulation amplifies and maintains the activation of both systems. This review focuses on three skin disorders: chronic urticaria (CU), which is considered autoimmune in approximately 50% of cases, bullous pemphigoid (BP), which is the prototype of autoimmune blistering disease, and psoriasis, which is an immune-mediated dermatitis. In CU, the activation of coagulation, which is due to the involvement of eosinophils and tissue factor pathways with the generation of thrombin, has local implications by increasing dermal vascular permeability. Preliminary data indicate that anticoagulant treatment with heparin and warfarin may be effective in reducing the symptoms of this disorder. In BP, the activation of coagulation seems to have both local and systemic implications. Locally, eosinophils and thrombin participate in bulla formation and tissue damage; systemically, the activation of coagulation may explain the increased thrombotic risk observed in these patients. In psoriasis, the activation of coagulation seems to be mainly systemic, potentially contributing to the increased cardiovascular risk associated with this disease. PMID:20477646

  15. Role of Platelet Parameters on Sudden Sensorineural Hearing Loss: A Case-Control Study in Iran.

    Directory of Open Access Journals (Sweden)

    Abbas Mirvakili

    Full Text Available Sudden sensorineural hearing loss (SSNHL is a common otological disorder characterized by a hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours. It has been established that platelet parameters, such as mean platelet volume, are associated with ischemic heart events, whose clinical manifestations are similar to those of SSNHL. Hence, we aimed to determine if the platelet count, mean platelet volume and platelet distribution width are related to the occurrence and severity of sudden sensorineural hearing loss. A case-control prospective study was conducted in a teaching hospital in Iran. One hundred-eight patients with SSNHL and an equal number of healthy, age- and sex-matched controls were enrolled in the study. Peripheral venous blood samples were collected from the subjects, and the platelet count, mean platelet volume and platelet distribution width were measured with an automated blood cell counter. Analysis of the audiometry and hematological test results using SPSS22 software showed no statistical correlation between the platelet parameters and the occurrence of SSNHL, but correlation coefficients showed a significant correlation between PDW and hearing loss severity in patients group. However, further investigation is required to unequivocally establish the absence of correlation between the platelet parameters and occurrence of SSNHL.

  16. Role of Platelet Parameters on Sudden Sensorineural Hearing Loss: A Case-Control Study in Iran.

    Science.gov (United States)

    Mirvakili, Abbas; Dadgarnia, Mohammad Hossein; Baradaranfar, Mohammad Hossein; Atighechi, Saeid; Zand, Vahid; Ansari, Abdollah

    2016-01-01

    Sudden sensorineural hearing loss (SSNHL) is a common otological disorder characterized by a hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours. It has been established that platelet parameters, such as mean platelet volume, are associated with ischemic heart events, whose clinical manifestations are similar to those of SSNHL. Hence, we aimed to determine if the platelet count, mean platelet volume and platelet distribution width are related to the occurrence and severity of sudden sensorineural hearing loss. A case-control prospective study was conducted in a teaching hospital in Iran. One hundred-eight patients with SSNHL and an equal number of healthy, age- and sex-matched controls were enrolled in the study. Peripheral venous blood samples were collected from the subjects, and the platelet count, mean platelet volume and platelet distribution width were measured with an automated blood cell counter. Analysis of the audiometry and hematological test results using SPSS22 software showed no statistical correlation between the platelet parameters and the occurrence of SSNHL, but correlation coefficients showed a significant correlation between PDW and hearing loss severity in patients group. However, further investigation is required to unequivocally establish the absence of correlation between the platelet parameters and occurrence of SSNHL.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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).

  4. Platelet activation and aggregation

    DEFF Research Database (Denmark)

    Jensen, Maria Sander; Larsen, O H; Christiansen, Kirsten;

    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...

  5. 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.

  6. Functional groups grafted nonwoven fabrics for blood filtration-The effects of functional groups and wettability on the adhesion of leukocyte and platelet

    Energy Technology Data Exchange (ETDEWEB)

    Yang Chao [State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Cao Ye [Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Chengdu 610081 (China); Sun Kang, E-mail: ksun@sjtu.edu.cn [State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Liu Jiaxin; Wang Hong [Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Chengdu 610081 (China)

    2011-01-15

    In this work, the effects of grafted functional groups and surface wettability on the adhesion of leukocyte and platelet were investigated by the method of blood filtration. The filter materials, poly(butylene terephthalate) nonwoven fabrics bearing different functional groups including hydroxyl (OH), carboxyl (COOH), sulfonic acid group (SO{sub 3}H) and zwitterionic sulfobetaine group ({sup +}N((CH{sub 3}){sub 2})(CH{sub 2}){sub 3}SO{sub 3}{sup Circled-Minus }) with controllable wettability were prepared by UV radiation grafting vinyl monomers with these functional groups. Our results emphasized that both surface functional groups and surface wettability had significant effects on the adhesion of leukocyte and platelet. In the case of filter materials with the same wettability, leukocytes adhering to filter materials decreased in the order: the surface bearing OH only > the surface bearing both OH and COOH > the surface bearing sulfobetaine group > the surface bearing SO{sub 3}H, while platelets adhering to filter materials decreased as the following order: the surface bearing SO{sub 3}H > the surface bearing both OH and COOH > the surface bearing OH only > the surface bearing sulfobetaine group. As the wettability of filter materials increased, both leukocyte and platelet adhesion to filter materials declined, except that leukocyte adhesion to the surface bearing OH only remained unchanged.

  7. Effect of erythrocytes and prostacyclin production in the effect of fructose and sorbitol on platelet activation in human whole blood in vitro.

    Science.gov (United States)

    De la Cruz, J P; Maximo, M A; Blanco, E; Moreno, A; Sánchez de la Cuesta, F

    1997-06-15

    We analyzed the in vitro effects of sorbitol and fructose on platelet function. Sorbitol and fructose increased platelet aggregation induced with adenosine diphosphate (ADP) or collagen in whole blood, but had no effect in platelet-rich plasma. The concentration that increased basal aggregation by 50% with ADP as the inducer was 12.89 +/- 1.55 mmol/L for fructose, and 18.99 +/- 2.01 mmol/L for sorbitol. When collagen was the inducer, these concentrations were 15.02 +/- 0.98 mmol/L for fructose, and 12.94 +/- 1.57 mmol/L for sorbitol. Both sugars increased, in a concentration-dependent way, the proaggregatory effect of erythrocytes, and erythrocyte uptake of adenosine. Time to uptake of 50% adenosine was 2.1 +/- 0.3 min in control samples, 0.14 +/- 0.01 min in the presence of fructose, and 0.23 +/- 0.03 min with sorbitol. Both sugars reduced vascular prostacyclin synthesis, with 50% inhibitory concentrations of 26.48 +/- 1.97 mmol/L for fructose, and 39.53 +/- 2.81 mmol/L for sorbitol. Both sugars also increased arterial lipid peroxidation by 30% (sorbitol) and 23% (fructose). We conclude that these two sugars enhance platelet function and disrupt the thromboxane/prostacyclin ratio.

  8. 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

  9. 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

  10. Imaging the interaction between dengue 2 virus and human blood platelets using atomic force and electron microscopy.

    Science.gov (United States)

    Ghosh, Kanjaksha; Gangodkar, Shobha; Jain, Preksha; Shetty, Shrimati; Ramjee, Sandhya; Poddar, Pankaj; Basu, Atanu

    2008-06-01

    Thrombocytopenia is frequently associated with dengue virus infection. Host factors such as anti-platelet immunopathogenic processes have been implicated in the origin of dengue-associated thrombocytopenia but the role of dengue virus in directly interacting with platelets and altering their hemostatic property remains incompletely understood. In the present study, we examined the effect of dengue 2 virus on the morphology and physiological activation profile of normal human platelets using atomic force microscopy, electron microscopy and flowcytometry. Platelets obtained from healthy donors were exposed to a cell culture-adapted 10(4) LD(50) dengue 2 virus isolate in vitro and the subsequent effect on morphology and activation biology studied. Our results show that dengue 2 virus exposure at doses comparable to natural viremic states in human infections can activate platelets with an increase in P-selectin expression and fibrinogen-binding property. Atomic force, scanning and transmission electron microscopy also showed typical activation-related morphological changes such as altered platelet membrane architecture, degranulation, presence of filopodia and dilatation of the open canalicular system in the dengue 2 virus-exposed platelets but not in the controls. Importantly, Japanese encephalitis virus exposure at the same dose did not activate platelets or show any morphological changes. Our findings suggest that dengue 2 virus may directly interact with and activate platelets - an event that might be important in the origin of dengue-associated thrombocytopenia. Detailed molecular characterization of this effect might provide key knowledge toward better prophylaxis of the hemostatic complications of dengue disease.

  11. Excess soluble CD40L contributes to blood brain barrier permeability in vivo: implications for HIV-associated neurocognitive disorders.

    Directory of Open Access Journals (Sweden)

    Donna C Davidson

    Full Text Available Despite the use of anti-retroviral therapies, a majority of HIV-infected individuals still develop HIV-Associated Neurocognitive Disorders (HAND, indicating that host inflammatory mediators, in addition to viral proteins, may be contributing to these disorders. Consistently, we have previously shown that levels of the inflammatory mediator soluble CD40L (sCD40L are elevated in the circulation of HIV-infected, cognitively impaired individuals as compared to their infected, non-impaired counterparts. Recent studies from our group suggest a role for the CD40/CD40L dyad in blood brain barrier (BBB permeability and interestingly, sCD40L is thought to regulate BBB permeability in other inflammatory disorders of the CNS. Using complementary multiphoton microscopy and quantitative analyses in wild-type and CD40L deficient mice, we now reveal that the HIV transactivator of transcription (Tat can induce BBB permeability in a CD40L-dependent manner. This permeability of the BBB was found to be the result of aberrant platelet activation induced by Tat, since depletion of platelets prior to treatment reversed Tat-induced BBB permeability. Furthermore, Tat treatment led to an increase in granulocyte antigen 1 (Gr1 positive monocytes, indicating an expansion of the inflammatory subset of cells in these mice, which were found to adhere more readily to the brain microvasculature in Tat treated animals. Exploring the mechanisms by which the BBB becomes compromised during HIV infection has the potential to reveal novel therapeutic targets, thereby aiding in the development of adjunct therapies for the management of HAND, which are currently lacking.

  12. Excess soluble CD40L contributes to blood brain barrier permeability in vivo: implications for HIV-associated neurocognitive disorders.

    Science.gov (United States)

    Davidson, Donna C; Hirschman, Michael P; Sun, Anita; Singh, Meera V; Kasischke, Karl; Maggirwar, Sanjay B

    2012-01-01

    Despite the use of anti-retroviral therapies, a majority of HIV-infected individuals still develop HIV-Associated Neurocognitive Disorders (HAND), indicating that host inflammatory mediators, in addition to viral proteins, may be contributing to these disorders. Consistently, we have previously shown that levels of the inflammatory mediator soluble CD40L (sCD40L) are elevated in the circulation of HIV-infected, cognitively impaired individuals as compared to their infected, non-impaired counterparts. Recent studies from our group suggest a role for the CD40/CD40L dyad in blood brain barrier (BBB) permeability and interestingly, sCD40L is thought to regulate BBB permeability in other inflammatory disorders of the CNS. Using complementary multiphoton microscopy and quantitative analyses in wild-type and CD40L deficient mice, we now reveal that the HIV transactivator of transcription (Tat) can induce BBB permeability in a CD40L-dependent manner. This permeability of the BBB was found to be the result of aberrant platelet activation induced by Tat, since depletion of platelets prior to treatment reversed Tat-induced BBB permeability. Furthermore, Tat treatment led to an increase in granulocyte antigen 1 (Gr1) positive monocytes, indicating an expansion of the inflammatory subset of cells in these mice, which were found to adhere more readily to the brain microvasculature in Tat treated animals. Exploring the mechanisms by which the BBB becomes compromised during HIV infection has the potential to reveal novel therapeutic targets, thereby aiding in the development of adjunct therapies for the management of HAND, which are currently lacking.

  13. [Pharmacological study on blood pressure in rats with bone disorders].

    Science.gov (United States)

    Shamoto, T

    1989-12-01

    To evaluate the relationship between the elevation of blood pressure and altered bone metabolism, the changes of systolic blood pressure in six experimental models for bone disorders were investigated. Rats used were either parathyroidectomized, ovariectomized, fed with a calcium-deficient diet, fed with a vitamin D-deficient diet, treated with HEBP (1-Hydroxyethylidene-1, 1-bisphosphonate) or treated with streptozotocin. Hypertension developed in 5-week-old male rats fed with a calcium-deficient diet for 2 weeks, which evoked hypocalcemia and nutritional hyperparathyroidism. The blood pressure returned to normal when fed with a normal calcium diet. In parathyroidectomized rats receiving a normal calcium diet, the blood pressure did not rise, though the plasma calcium level decreased to an extent similar to the rats fed with the calcium-deficient diet. These findings seem to indicate that hyperparathyroidism, but not hypocalcemia, was involved in the elevation of blood pressure in rats fed with a calcium-deficient diet. Hypertension was not observed in rats fed with a vitamin D-deficient diet or treated with streptozotocin. These rats showed not only an increase in parathyroid hormone (PTH) but also a decrease in 1,25 (OH)2 D3. These results may suggest that the presence of 1,25 (OH)2D3 as well as the enhanced parathyroid function is necessary for the development of hypertension. The elevated blood pressure was reduced by a calcium antagonist, nifedipine, or by calcium supplementation, but not by an inhibitor of angiotensin-converting enzyme, captopril, or by calcitonin. This may indicate that hypertension due to nutritional hyperparathyroidism responds to the calcium antagonist nifedipine and to calcium supplementation, but does not depend on renin or salt. Furthermore, an acute hypotensive effect by human PTH (1-34) was not observed in the hypertension of calcium-deficient rats, suggesting the difference between acute and chronic effects of PTH. The hypertension

  14. 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

  15. 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...... 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....

  16. 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...

  17. Influence factors of handmade concentratd blood platelets%手工制备浓缩血小板影响因素探讨

    Institute of Scientific and Technical Information of China (English)

    唐泽萍

    2012-01-01

    Objective To analyze the influence factors of handmade concentrated blood platelets and to improve the quality and the clinical injection effect of handmade concentrated platelets. Methods The blood donors not taken aspirin before donating blood in 72 hours were randomly enrolled in this study. The peripheral blood platelets counts were normal; blood were collected smoothly; then platelets concentrate were reserved by same centrifuging method (platelet-rich plasma method). The influence of centrifugal conditions and whole blood specifications on collecting platelets were analyzed. Results The 400ml whole blood under 2000rp, 2100rpm, 2200rpm, centrifugalize 5min platelets (unit: 109/L) 84. 0±14、90. 5±10. 5, 3. 89±0. 48, and 6min platelets (unit: 10°/L 86. 3±11. 5, 121. 5±17. 7, 85.0±16. 5. There-suits under 2100rpm and centrifugalized 6min have significant difference, compared with other groups; There is no obvious difference between other groups (P>0. 5). The difference between the platelets (1. 46±0. 28, 3. 53±0. 66, 4. 86± 0.71) prepared with 400, 300, 200ml whole blood respectively was not obvious, however the difference is significant compared 200ml with 400, 30 0ml (P<0. 01). Conclusion Under the same separation method, but different centrifuga-tion conditions, type of blood, the platelet concentrate prepared with 400 ml of whole blood under the condition that the rotating speed is 2100 rpm, the centrifuging time is 6 min, and the centrifuging temperature is 22 degrees centigrade has the highest content and the best collecting effect.%目的 探讨手工制备浓缩血小板的影响因素,提高手工浓缩血小板的质量和临床输注效果.方法 随机选择献血者且献血前72小时内未服用过阿斯匹林类药物,外周血小板计数正常,采血顺畅,采用相同的分离方法(富含血小板血浆法)手工制备浓缩血小板,观察不同规格的全血,或不同的离心条件,对收集血小板的影响.结果 400ml

  18. 手工制备浓缩血小板影响因素的探讨%Influence factors of handmade blood platelets concentrate

    Institute of Scientific and Technical Information of China (English)

    唐泽萍

    2012-01-01

    目的 探讨手工制备浓缩血小板的影响因素,提高手工浓缩血小板的质量和临床输注效果.方法 随机选择献血前72小时内未服用过阿斯匹林类药物的献血者,外周血小板计数正常,采血顺畅,采用相同的分离方法(富含血小板血浆法)制备手工浓缩血小板,观察不同规格的全血,或不同的离心条件对收集血小板的影响.结果 400ml全血分别在2000、2100和2200 rpm,离心5 min血小板为(84.0±14)、(90.5±10.5)、(3.89±0.48) 109/L,离心6min血小板为(86.3±11.5)、(121.5±17.7)、(85.0±16.5)109/L,经统计学处理2100 rpm离心6 min结果与其它组比较差异显著(P<0.01);其它各组相互比较差异不显著(P>0.5).全血量分别为400、300、200ml时分离出的血小板为(1.46±0.28)、(3.53±0.66)、(4.86±0.71)109/L,400、300ml间比较差异不显著(P>0.5),200ml与400、300ml间比较差异显著(P<0.01).结论 采用相同的分离法,不同的离心条件、血液规格收集血小扳均有影响,400ml的全血,转速为2 100rpm/min,6min,22℃离心制备的浓缩血小板含量最高,收集效果最好.%Objective To analyze the influence factors of handmade blood platelets concentrate and improve the quality and the clinical injection effect of handmade platelets concentrate. Methods The blood donors who hadn't taken aspirin medicine before donating blood in 72 hours were randomly enrolled in this study: peripheral blood platelets counts were normal; blood were collected smoothly; then platelets concentrate were reserved by same centrifuging method ( platelet-rich plasma method) to discuss the influence of centrifugal conditions or whole blood specifications on collecting platelets. Results The 400ml whole blood under 2000rpp, 2100rpm, 2200rpm, centrifugalize 5min platelets (unit:109/ L) 84.0±14,90.5±10.5,3.89±0.48, and 6min platelets (unit: 109/L) 86. 3± 11. 5、121. 5± 17. 7、85. 0± 16. 5. The results under 2100rpm and centrifugalized 6min

  19. Involvement of Ca2+ Activated Cl- Channel Ano6 in Platelet Activation and Apoptosis

    Directory of Open Access Journals (Sweden)

    Guoxing Liu

    2015-11-01

    Full Text Available Background/Aims: The ubiquitously expressed Ca2+ Activated Cl- Channel Ano6 participates in the stimulation of cell membrane scrambling. Defective Ano6 underlies the Scott syndrome, an inherited bleeding disorder with impaired scrambling of plasma membrane phospholipids. At least in theory, the bleeding disorder of Scott syndrome may result from impaired platelet function. Activators of platelets include thrombin and collagen related peptide (CRP, which trigger increase of cytosolic Ca2+-activity ([Ca2+]i, production of reactive oxygen species (ROS, degranulation, integrin activation, as well as cell shrinkage and phospholipid scrambling of the cell membrane. The present study thus explored whether Ano6 modifies activation-induced alterations of cytosolic Ca2+-activity ([Ca2+]i, degranulation (P-selectin exposure, integrin activation, phosphatidylserine exposure on the platelet surface and platelet volume. Methods: Platelets from mice lacking Ano6 (ano6-/- were compared to platelets from corresponding wild-type mice (ano6+/+. [Ca2+]i was estimated from Fluo-3 fluorescence, ROS from DCFDA fluorescence, degranulation from P-selectin abundance, integrin activation from αIIbβ3-integrin abundance, phosphatidylserine abundance from annexin-V-binding, and cell volume from forward scatter. Results: Platelet number in blood was slightly higher in ano6-/- mice than in ano6+/+ mice. Without activation [Ca2+]i and volume were similar in ano6-/- and ano6+/+ platelets as well as ROS abundance, P-selectin abundance, αIIbβ3 integrin activation, and phosphatidylserine exposure were negligible in both genotypes. Thrombin (0.01 U/ml and CRP (2 or 5 µg/ml increased [Ca2+]i, ROS abundance, platelet degranulation, αIIbβ3 integrin activation, and triggered annexin-V-binding as well as cell shrinkage, all effects less pronounced in ano6-/- than in ano6+/+ platelets. Conclusions: Genetic knockout of Ano6 blunts thrombin- and CRP-induced activation and apoptosis

  20. 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

  1. A novel thrombopoietin signaling defect in polycythemia vera platelets.

    Science.gov (United States)

    Moliterno, A R; Siebel, K E; Sun, A Y; Hankins, W D; Spivak, J L

    1998-01-01

    The pathogenesis of polycythemia vera (PV), a disease involving a multipotent hematopoietic progenitor cell, is unknown. Thrombopoietin (TPO) is a newly characterized hematopoietic growth factor which regulates the production of multipotent hematopoietic progenitor cells as well as platelets. To evaluate the possibility that an abnormality in TPO-mediated signal transduction might be involved in the pathogenesis of PV, we examined TPO-induced protein tyrosine phosphorylation using platelets as a surrogate model system. Platelets were isolated from the blood of patients with PV as well as from patients with other chronic myeloproliferative disorders and control subjects. Impaired TPO-mediated platelet protein tyrosine phosphorylation was a consistent observation in patients with PV as well as those with idiopathic myelofibrosis (IMF), in contrast to patients with essential thrombocytosis, chronic myelogenous leukemia, secondary erythrocytosis, iron deficiency anemia, hemochromatosis, or normal volunteers. Thrombin-mediated platelet protein tyrosine phosphorylation was intact in PV platelets as was expression of the appropriate tyrosine kinases and their cognate substrates. However, expression of the platelet TPO receptor, Mpl, as determined by immunoblotting, chemical crosslinking or flow cytometry was markedly reduced or absent in 34 of 34 PV patients and also in 13 of 14 IMF patients. Impaired TPO-induced protein tyrosine phosphorylation in PV and IMF platelets was uniformly associated with markedly reduced or absent expression of Mpl. We conclude that reduced expression of Mpl is a phenotypic characteristic of platelets from patients with PV and IMF. The abnormality appears to distinguish PV from other forms of erythrocytosis and may be involved in the platelet function defect associated with PV.

  2. 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.

  3. Gasotransmitters and platelets.

    Science.gov (United States)

    Truss, Nicola J; Warner, Timothy D

    2011-11-01

    Platelets are essential to prevent blood loss and promote wound healing. Their activation comprises of several complex steps which are regulated by a range of mediators. Over the last few decades there has been intense interest in a group of gaseous mediators known as gasotransmitters; currently comprising nitric oxide (NO), carbon monoxide (CO) and hydrogen sulphide (H(2)S). Here we consider the action of gasotransmitters on platelet activity. NO is a well established platelet inhibitor which mediates its effects predominantly through activation of soluble guanylyl cyclase leading to a decrease in intraplatelet calcium. More recently CO has been identified as a gasotransmitter with inhibitory actions on platelets; CO acts through the same mechanism as NO but is less potent. The in vivo and platelet functions of the most recently identified gasotransmitter, H(2)S, are still the subject of investigations, but they appear generally inhibitory. Whilst there is evidence for the individual action of these mediators, it is also likely that combinations of these mediators are more relevant regulators of platelets. Furthermore, current evidence suggests that these mediators in combination alter the production of each other, and so modify the circulating levels of gasotransmitters. The use of gasotransmitters as therapeutic agents is also being explored for a range of indications. In conclusion, the importance of NO in the regulation of vascular tone and platelet activity has long been understood. Other gasotransmitters are now establishing themselves as mediators of vascular tone, and recent evidence suggests that these other gasotransmitters may also modulate platelet function.

  4. 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

  5. Disruption and activation of blood platelets in contact with an antimicrobial composite coating consisting of a pyridinium polymer and AgBr nanoparticles.

    Science.gov (United States)

    Stevens, Kris N; Knetsch, Menno L; Sen, Ayusman; Sambhy, Varun; Koole, Leo H

    2009-09-01

    Composite materials made up from a pyridinium polymer matrix and silver bromide nanoparticles embedded therein feature excellent antimicrobial properties. Most probably, the antimicrobial activity is related to the membrane-disrupting effect of both the polymer matrix and Ag(+) ions; both may work synergistically. One of the most important applications of antimicrobial materials would be their use as surface coatings for percutaneous (skin-penetrating) catheters, such as central venous catheters (CVCs). These are commonly used in critical care, and serious complications due to bacterial infection occur frequently. This study aimed at examining the possible effects of a highly antimicrobial pyridinium polymer/AgBr composite on the blood coagulation system, i.e., (i) on the coagulation cascade, leading to the formation of thrombin and a fibrin cross-linked network, and (ii) on blood platelets. Evidently, pyridinium/AgBr composites could not qualify as coatings for CVCs if they trigger blood coagulation. Using a highly antimicrobial composite of poly(4-vinylpyridine)-co-poly(4-vinyl-N-hexylpyridinium bromide) (NPVP) and AgBr nanoparticles as a thin adherent surface coating on Tygon elastomer tubes, it was found that contacting blood platelets rapidly acquire a highly activated state, after which they become substantially disrupted. This implies that NPVP/AgBr is by no means blood-compatible. This disqualifies the material for use as a CVC coating. This information, combined with earlier findings on the hemolytic effects (i.e., disruption of contacting red blood cells) of similar materials, implies that this class of antimicrobial materials affects not only bacteria but also mammalian cells. This would render them more useful outside the biomedical field.

  6. Adhesion, activation, and aggregation of blood platelets and biofilm formation on the surfaces of titanium alloys Ti6Al4V and Ti6Al7Nb.

    Science.gov (United States)

    Walkowiak-Przybyło, M; Klimek, L; Okrój, W; Jakubowski, W; Chwiłka, M; Czajka, A; Walkowiak, B

    2012-03-01

    Titanium alloys are still on the top list of fundamental materials intended for dental, orthopedics, neurological, and cardiovascular implantations. Recently, a special attention has been paid to vanadium-free titanium alloy, Ti6Al7Nb, that seems to represent higher biocompatibility than traditional Ti6Al4V alloy. Surprisingly, these data are not thoroughly elaborated in the literature; particularly there is a lack of comparative experiments conducted simultaneously and at the same conditions. Our study fills these shortcomings in the field of blood contact and microbiological colonization. To observe platelets adhesion and biofilm formation on the surfaces of compared titanium alloys, fluorescence microscope Olympus GX71 and scanning electron microscope HITACHI S-3000N were used. Additionally, flow cytometry analysis of platelets aggregation and activation in the whole blood after contact with sample surface, as an essential tool for biomaterial thrombocompatibility assessment, was proposed. As a result of our study it was demonstrated that polished surfaces of Ti6Al7Nb and Ti6Al4V alloys after contact with whole citrated blood and E. coli bacterial cells exhibit a considerable difference. Overall, it was established that Ti6Al4V has distinct tendency to higher thrombogenicity, more excessive bacterial biofilm formation and notable cytotoxic properties in comparison to Ti6Al7Nb. However, we suggest these studies should be extended for other types of cells and biological objects.

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. 配型血小板输注在血液病患者中的应用%The Application of Cross-matched Platelet in Patients with Blood Diseases

    Institute of Scientific and Technical Information of China (English)

    叶静梅; 许志晟; 李翊泉; 李碧珊; 谭获

    2015-01-01

    目的:通过对比血小板配型前后血小板的输注效果,评估配型血小板在血液病患者中的疗效。方法以临床出血症状改善的情况、血小板计数增高指数(CCI)及血小板恢复百分率(PPR)为标准,对比配型前后血小板的输注效果。另外以临床输注血小板的次数分组,比较不同输注次数的患者出现血小板输注无效的差异。结果与配型前相比,配型血小板大大提高输注疗效(P <0.01),临床上输注5次血小板以上的患者比5次以下者出现血小板输注无效(PTR)的机率大大提高(P <0.01)。结论 PTR 的出现与血小板输注次数有关。在出现 PTR 的血液病患者中使用配型血小板输注,可提高输注效果。%Objective To evaluate the clinical significance of platelets cross-matched on platelet trans-fusion refractoriness of blood diseases by comparing the efficiency of transfusion before and after platelets cross-matched. Methods Regarding the improvement of haemorrhage symptom,corrected count increment (CCI),percent platelet recovery(PPR)as the standard,the efficiency of transfusion of before and after plate-lets cross-matched were compared. And comparing the difference of platelet transfusion refractoriness(PTR)by regarding on different times of platelet transfusion. Results Compare with before cross- matched,after cross-matched platelet transfusion was greatly improve curative effect( P < 0. 01). And the more times of platelet transfusion(≥5),the more probability of PTR was appearing(P < 0. 01). Conclusion PTR was related to the number of platelet transfusion. Cross- matched platelet transfusionis an effective method in those patients refractory to random platelet transfusions. It should advocate to use cross-matched platelet in blood diseases.

  12. 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

  13. Human platelets produced in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice upon transplantation of human cord blood CD34(+) cells are functionally active in an ex vivo flow model of thrombosis.

    Science.gov (United States)

    Salles, Isabelle I; Thijs, Tim; Brunaud, Christine; De Meyer, Simon F; Thys, Johan; Vanhoorelbeke, Karen; Deckmyn, Hans

    2009-12-01

    Xenotransplantation systems have been used with increasing success to better understand human hematopoiesis and thrombopoiesis. In this study, we demonstrate that production of human platelets in nonobese diabetic/severe combined immunodeficient mice after transplantation of unexpanded cord-blood CD34(+) cells was detected within 10 days after transplantation, with the number of circulating human platelets peaking at 2 weeks (up to 87 x 10(3)/microL). This rapid human platelet production was followed by a second wave of platelet formation 5 weeks after transplantation, with a population of 5% still detected after 8 weeks, attesting for long-term engraftment. Platelets issued from human hematopoietic stem cell progenitors are functional, as assessed by increased CD62P expression and PAC1 binding in response to collagen-related peptide and thrombin receptor-activating peptide activation and their ability to incorporate into thrombi formed on a collagen-coated surface in an ex vivo flow model of thrombosis. This interaction was abrogated by addition of inhibitory monoclonal antibodies against human glycoprotein Ibalpha (GPIbalpha) and GPIIb/IIIa. Thus, our mouse model with production of human platelets may be further explored to study the function of genetically modified platelets, but also to investigate the effect of stimulators or inhibitors of human thrombopoiesis in vivo.

  14. Physiopathology of blood platelets: a model system for studies of cell-to-cell interaction. Progress report, November 1, 1978-October 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, M G

    1979-01-01

    In this report, we will limit ourselves to the detailed description of four major sections of our research done during the past year: platelet interaction with tumor cells; studies of the interaction of platelets with macrophages; interaction of platelets with vessel walls; and further studies of cyclic nucleotides on stored platelets.

  15. 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...

  16. 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.

  17. Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part II: platelet-related biologic features.

    Science.gov (United States)

    Dohan, David M; Choukroun, Joseph; Diss, Antoine; Dohan, Steve L; Dohan, Anthony J J; Mouhyi, Jaafar; Gogly, Bruno

    2006-03-01

    Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. In this second article, we investigate the platelet-associated features of this biomaterial. During PRF processing by centrifugation, platelets are activated and their massive degranulation implies a very significant cytokine release. Concentrated platelet-rich plasma platelet cytokines have already been quantified in many technologic configurations. To carry out a comparative study, we therefore undertook to quantify PDGF-BB, TGFbeta-1, and IGF-I within PPP (platelet-poor plasma) supernatant and PRF clot exudate serum. These initial analyses revealed that slow fibrin polymerization during PRF processing leads to the intrinsic incorporation of platelet cytokines and glycanic chains in the fibrin meshes. This result would imply that PRF, unlike the other platelet concentrates, would be able to progressively release cytokines during fibrin matrix remodeling; such a mechanism might explain the clinically observed healing properties of PRF.

  18. Molecular Basis Linking Platelet to Inflammation

    Institute of Scientific and Technical Information of China (English)

    马丽萍

    2010-01-01

    @@ Introduction Blood platelets not only play an important role in hemostasis and thrombosis,but increasing evidence show that they participate in the induction of inflammation.Firstly,platelets contain and release cytokines and immune mediators.And platelets are able to modulate and regulate the function of surrounding cells by adhesion molecules or by the release of various factors.

  19. Dengue platelets meet Sir Arthur Conan Doyle.

    Science.gov (United States)

    Bray, Paul F

    2013-11-14

    In this issue of Blood, Hottz et al provide compelling evidence that dengue virus (DV) induces (1) platelet synthesis of interleukin-1b (IL-1b); (2) platelet-derived IL-1b–containing microvesicles (MVs) that increase vascular permeability; and (3) DV-triggered inflammasome activation in platelets.

  20. 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.

  1. The Implementation of 2U Platelets Collected at the Huaian Blood Center%2U单采血小板的采集在淮安市中心血站的实施

    Institute of Scientific and Technical Information of China (English)

    滕平; 谢峰

    2015-01-01

    目的 为了保证献血者在捐献双份血小板后,体内剩余血小板仍能达到正常人水平,保障献血者的健康;另外也要使终产品符合国标的质量要求,达到患者的安全治疗需要的剂量. 方法 依据献血者体重和采前血小板计数,确定采集双份血小板的标准,对双份献血者体重的最低要求是:男≥60 kg,女≥55 kg;采前计数血小板的最低值为≥200×109/L.结果 经血细胞分离机采集后,对献血者重新抽样检查和对终产品进行验证,采集双份血小板后,献血者体内剩余血小板≥1.0×1011/L的正常人水平;采集后的终产品血小板计数≥5.0×1011/袋,白细胞≤5×108/袋,红细胞≤8× 109/袋,都能达到国标要求.结论 符合条件的献血者1次采集双份血小板安全可行,这样既能解决单采血小板供者的不足,减少患者输注血小板后抗体产生的机会,同时也可大大节约单采血小板成本.%Objective To ensure blood donors after double platelet donation, remaining in vivo platelet can still reach nor-mal level, to keep the donors of health;in addition to the final products to meet the requirements of the national standard of quality, to reach the safe treatment of the patients required dose. Methods According to the blood donation weight and re-covery of platelet count, the criteria for determining double samples of platelet, double blood donation is the weight of the minimum requirements: male is more than or equal to 60 kg, female is more than or equal to 55 kg. The lowest values of platelet count is equal or more than 200×109/L. Results Blood cell separator after collection, the blood donors to sampling inspection and the final product verification, after double platelet collection and normal human level of blood donors in residual platelet is more than or equal to 1.0×1011/L; after collection of the final products platelet count is greater than or e-qual to 5.0 ×1011/bag, white blood cell is less than or

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

    Directory of Open Access Journals (Sweden)

    Seyed Ahmad Raeissadat

    2014-01-01

    Full Text Available 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.

  3. 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

  4. 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...

  5. 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...

  6. 双份机采血小板采集前后血常规结果分析%Study on the changes of the donor's blood cell counts before and after double apheresis platelets

    Institute of Scientific and Technical Information of China (English)

    伍娟; 孙革; 庄乃保; 熊恺轩; 王霞; 孙雄飞

    2015-01-01

    Objective To study the changes of the donor's blood routine indexes before and after double apheresis platelets, and then to explore the efficiency and the safety of double apheresis platelets. Methods The blood cell counts of 50 donors were examined by blood counting instrument before and after double apheresis plate-lets, and the data was analyzed on Paired Samples t-Test. Results After double apheresis platelets, PLT was signifi-cantly lower than that before double apheresis platelets (P0.05). And examination confirmed that the quality of the apheresis platelets products was up to specification, with the amount of platelets reaching 250 × 109/L and the qualification rate of 100%. Conclusion Double apheresis platelets can improve the efficiency and safety of platelets donation, and it would not affect the blood routine indexes of the donors.%目的:通过分析捐献双份机采血小板捐献者捐献前后血常规参数的变化,评价捐献双份机采血小板的效率和安全性。方法随机抽取本中心双份机采血小板捐献者50例,应用血细胞计数仪分别检测其献血前后血常规主要参数水平,并进行配对t检验。结果献血前与献血后PLT计数比较差异有统计学意义(P0.05),采集的血小板均能达到250×109/L,机采血小板合格率为100%,献血者无不适反应。结论双份机采血小板可以提高血小板采集效率,但不会明显影响捐献者血常规各主要参数的水平,机采双份血小板对捐献者不会有明显影响。

  7. Regional cerebral blood flow distribution in newly diagnosed schizophrenia and schizophreniform disorder

    DEFF Research Database (Denmark)

    Rubin, P; Holm, S; Madsen, P L;

    1994-01-01

    Regional cerebral blood flow distribution (rCBF) in 24 first admissions with schizophrenia or schizophreniform disorder and in 17 healthy volunteers was examined. Single photon emission computed tomography with a brain-retained tracer, technetium-99m-d,l-hexamethyl-propylene amine oxime, was used...... interrelationship in schizophrenia and schizophreniform disorder....

  8. Stability and reproducibility of ADVIA 120-measured red blood cell and platelet parameters in dogs, cats, and horses, and the use of reticulocyte haemoglobin content (CH(R)) in the diagnosis of iron deficiency

    NARCIS (Netherlands)

    Prins, M.; van Leeuwen, M.W.; Teske, E.

    2009-01-01

    Tijdschr Diergeneeskd. 2009 Apr 1;134(7):272-8. Stability and reproducibility of ADVIA 120-measured red blood cell and platelet parameters in dogs, cats, and horses, and the use of reticulocyte haemoglobin content (CH(R)) in the diagnosis of iron deficiency. Prins M, van Leeuwen MW, Teske E. Departm

  9. 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

  10. 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...

  11. TISSUE-TYPE PLASMINOGEN-ACTIVATOR AND FIBRIN MONOMERS SYNERGISTICALLY CAUSE PLATELET DYSFUNCTION DURING RETRANSFUSION OF SHED BLOOD AFTER CARDIOPULMONARY BYPASS

    NARCIS (Netherlands)

    DEHAAN, J; SCHONBERGER, J; HAAN, J; VANOEVEREN, W; EIJGELAAR, A

    1993-01-01

    Reduced hemostasis and bleeding tendency after cardiopulmonary bypass results from platelet dysfunction induced by the bypass procedure. The causes of this acquired platelet dysfunction are still subject to discussion, although, recently, greater emphasis has been placed on an overstimulated fibrino

  12. 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

  13. 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.

  14. Platelets, inflammation and tissue regeneration.

    Science.gov (United States)

    Nurden, Alan T

    2011-05-01

    Blood platelets have long been recognised to bring about primary haemostasis with deficiencies in platelet production and function manifesting in bleeding while upregulated function favourises arterial thrombosis. Yet increasing evidence indicates that platelets fulfil a much wider role in health and disease. First, they store and release a wide range of biologically active substances including the panoply of growth factors, chemokines and cytokines released from a-granules. Membrane budding gives rise to microparticles (MPs), another active participant within the blood stream. Platelets are essential for the innate immune response and combat infection (viruses, bacteria, micro-organisms). They help maintain and modulate inflammation and are a major source of pro-inflammatory molecules (e.g. P-selectin, tissue factor, CD40L, metalloproteinases). As well as promoting coagulation, they are active in fibrinolysis; wound healing, angiogenesis and bone formation as well as in maternal tissue and foetal vascular remodelling. Activated platelets and MPs intervene in the propagation of major diseases. They are major players in atherosclerosis and related diseases, pathologies of the central nervous system (Alzheimers disease, multiple sclerosis), cancer and tumour growth. They participate in other tissue-related acquired pathologies such as skin diseases and allergy, rheumatoid arthritis, liver disease; while, paradoxically, autologous platelet-rich plasma and platelet releasate are being used as an aid to promote tissue repair and cellular growth. The above mentioned roles of platelets are now discussed.

  15. 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

  16. 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. ...

  17. 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

  18. 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...

  19. Stability and reproducibility of ADVIA 120-measured red blood cell and platelet parameters in dogs, cats, and horses, and the use of reticulocyte haemoglobin content (CH(R)) in the diagnosis of iron deficiency.

    Science.gov (United States)

    Prins, M; van Leeuwen, M W; Teske, E

    2009-04-01

    Modern laser-based haematology analysers such as the ADVIA 120 have species-specific software and offer the possibility of assessing new haematological parameters. These parameters have yet to be evaluated, and as these analysers are often used in referral laboratories, it is important to know whether the values of haematological parameters change during sample transport. Therefore, samples of EDTA-anticoagulated blood from nine healthy dogs and EDTA- and citrate-anticoagulated blood from six healthy horses were collected and stored at room temperature for 72 and 48 hours, respectively. In canine samples, WBC and the red blood cell parameters Hb, Hb(cell), Ht, MCV, and MCHC changed significantly after only 24 hours of storage. Thus if canine blood samples need to be stored for 24 hours or longer, Hb, RBC, and MCH would appear to be more reliable parameters than Ht, Hb(cell), MCV, and MCHC. The cytoplasmic haemoglobin content (CH(R)) remained stable up to 48 hours. Both dog and horse platelet numbers were stable over time when blood was anticoagulated with EDTA. Of the platelet-derived parameters, MPC was already significantly lower 2 hours after collection of equine blood samples and was also significantly lower 24 hours after collection of canine blood samples. In contrast, MPV levels were significantly higher 48 hours after sample collection. Initial platelet numbers and platelet parameters were significantly different in citrate-anticoagulated blood and EDTA-anticoagulated blood, and platelet numbers and MPM decreased significantly in citrate-anticoagulated blood samples after only 4 hours of storage. After reference intervals for CH(R) had been established using samples from 53 non-anaemic dogs and 150 non-anaemic cats, the use of CH(R) to detect iron deficiency anaemia was tested in 63 dogs and 55 cats with different diseases. With the help of ROC curves, the optimal cut-off point was determined to be 1.22 fmol in dogs and 0.88 fmol in cats, resulting in a

  20. 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...

  1. Effects of Xuezhikang Capsule(血脂康胶囊) on Blood Lipids,Platelet Activation and Coagulation-Fibrinolysis Activity in Patients with Hyperlipidemia

    Institute of Scientific and Technical Information of China (English)

    刘志高; 余细勇

    2004-01-01

    Objective: To investigate the effects of Xuezhikang capsule (XZK, 血脂康胶囊) on blood lipids level, platelet activation and coagulation-fibrinolysis activity in patients with hyerlipidemia. Methods:Seventy-six patients of hyperlipidemia were randomly divided into two groups, the XZK group (n = 38) treated with XZK 600mg, taken two times per day and the Simvastatin (SIM) group (n = 38) treated with SIM 20mg per day, with the treatment lasting 8 weeks for both groups. Levels of fasting serum lipids, including total cholesterol (TC), triglyceride (TG), high and low density l ipoprotein cholesterol (HDL-C and LDL-C),plasma GMP-140, fibrinogen (FIB), tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAl-) and prothrombin time (PT) were all measured before and 8 weeks after treatment. Data were compared before and after treatment and also compared with those measured in 20 healthy subjects of control. Results: Before treantment the levels of TC, TG and LDL-C were obviously higher and HDL-C level was significantly lower in hyperlipidemia patients than those in healthy subjects ( P<0.05 or P<0.01). After 4-8 weeks of XZK treatment, the levels of TC, TG, LDL-C and FIB and activities of GMP-140 and PAl-1 were obviously lowered (P<0.05 or P<0.01). But in the SIM group there was no obvious change in FIB (P>0.05), instead it showed obvious increase of HDL-C and decrease of TC and LDL-C after treatment ( P<0.05 or P<0.01). Conclusion: XZK could inhibit platelet activity and improve coagulation-fibrinolysis function, besides its lipids lowering effect.

  2. 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...

  3. Platelets: crossroads of immunity and hemostasis.

    Science.gov (United States)

    Jenne, Craig N

    2014-07-31

    In this issue of Blood, Koupenova and colleagues report that platelets express functional TOLL-like receptor 7 (TLR7) and contribute to host survival during viral infection. Through a series of experiments utilizing mice deficient for TLR7 together with adoptive transfer of wild-type platelets, Koupenova et al demonstrate that platelets specifically respond to viral analogs and intact virus, leading to platelet activation and binding to various leukocyte subsets. Perhaps most importantly, this platelet activation appears absolutely essential for host survival during infection with some viral pathogens such as encephalomyocarditis virus (EMCV).

  4. 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

  5. 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 protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... experienced three or more recent stressful events (n=26) had decreased whole blood BDNF levels compared to high-risk women with two or less recent stressful events (n=35), 21.6+/-7.0 vs. 18.5+/-4.1 ng/ml, respectively, (p

  6. 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

  7. 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.

  8. Role of histaminergic system in blood-brain barrier dysfunction associated with neurological disorders.

    Science.gov (United States)

    Bañuelos-Cabrera, Ivette; Valle-Dorado, María Guadalupe; Aldana, Blanca Irene; Orozco-Suárez, Sandra Adela; Rocha, Luisa

    2014-11-01

    Blood-brain barrier (BBB) disruption has been associated with several acute and chronic brain disorders such as Alzheimer's disease, Parkinson's disease and epilepsy. This represents a critical situation because damaged integrity of the BBB is related to the influx of immune mediators, plasma proteins and other outside elements from blood to the central nervous system (CNS) that may trigger a cascade of events that leads to neuroinflammation. In this review, evidence that mast cells and the release of factors such as histamine play an important role in the neuroinflammatory process associated with brain disorders such as Alzheimer's disease, Parkinson's disease and epilepsy is presented.

  9. 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.

  10. 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。

  11. The accuracy of platelet counting in thrombocytopenic blood samples distributed by the UK National External Quality Assessment Scheme for General Haematology.

    Science.gov (United States)

    De la Salle, Barbara J; McTaggart, Paul N; Briggs, Carol; Harrison, Paul; Doré, Caroline J; Longair, Ian; Machin, Samuel J; Hyde, Keith

    2012-01-01

    A knowledge of the limitations of automated platelet counting is essential for the effective care of thrombocytopenic patients and management of platelet stocks for transfusion. For this study, 29 external quality assessment specimen pools with platelet counts between 5 and 64 × 10(9)/L were distributed to more than 1,100 users of 23 different hematology analyzer models. The same specimen pools were analyzed by the international reference method (IRM) for platelet counting at 3 reference centers. The IRM values were on average lower than the all-methods median values returned by the automated analyzers. The majority (~67%) of the automated analyzer results overestimated the platelet count compared with the IRM, with significant differences in 16.5% of cases. Performance differed between analyzer models. The observed differences may depend in part on the nature of the survey material and analyzer technology, but the findings have implications for the interpretation of platelet counts at levels of clinical decision making.

  12. 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

  13. Platelets in inflammation and infection.

    Science.gov (United States)

    Jenne, Craig N; Kubes, Paul

    2015-01-01

    Although platelets are traditionally recognized for their central role in hemostasis, many lines of research clearly demonstrate these rather ubiquitous blood components are potent immune modulators and effectors. Platelets have been shown to directly recognize, sequester and kill pathogens, to activated and recruit leukocytes to sites of infection and inflammation, and to modulate leukocyte behavior, enhancing their ability to phagocytose and kill pathogens and inducing unique effector functions, such as the production of Neutrophil Extracellular Traps (NETs). This multifaceted response to infection and inflammation is due, in part, to the huge array of soluble mediators and cell surface molecules expressed by platelets. From their earliest origins as primordial hemocytes in invertebrates to their current form as megakaryocyte-derived cytoplasts, platelets have evolved to be one of the key regulators of host intravascular immunity and inflammation. In this review, we present the diverse roles platelets play in immunity and inflammation associated with autoimmune diseases and infection. Additionally, we highlight recent advances in our understanding of platelet behavior made possible through the use of advanced imaging techniques that allow us to visualize platelets and their interactions, in real-time, within the intact blood vessels of a living host.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Hyoung; Chung, Yong An; Seo, Ye Young; Yoo, Ik Dong; Na, Sae Jung; Jung, Hyun Suk; Kim, Ki Jun [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2009-04-15

    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: 19approx52 years, average age: 29.3+-9.9 years) and 14 normal volunteers (male: 8, female: 6, age range: 19approx53 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

  15. Transfusion of platelets, but not of red blood cells, is independently associated with nosocomial infections in the critically ill

    NARCIS (Netherlands)

    Engele, Leo J.; Straat, Marleen; van Rooijen, Ingeborg H M; de Vooght, Karen M K; Cremer, Olaf L.; Schultz, Marcus J.; Bos, Lieuwe D J; Juffermans, Nicole P.

    2016-01-01

    Background: Red blood cell (RBC) transfusion has been associated with nosocomial infection in the critically ill patients. However, this association may be confounded by length of stay, as prolonged intensive care unit (ICU stay) increases both risk of infection and risk of transfusion. Also, it is

  16. 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

    -operating characteristic curve of 0.81 (P test. The present findings of altered POLG, OGG1 and NDUFV2 expression point to disturbances within mitochondrial function and DNA repair mechanisms...... as a diagnostic and state biomarker in bipolar disorder. First, messenger RNA levels of 19 candidate genes were assessed in peripheral blood mononuclear cells of 37 rapid cycling bipolar disorder patients in different affective states (depression, mania and euthymia) during a 6-12-month period and in 40 age...... in bipolar disorder. Further, a composite gene expression measure could hold promise as a potential diagnostic biomarker....

  17. 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,…

  18. Platelets kill intraerythrocytic malarial parasites and mediate survival to infection.

    Science.gov (United States)

    McMorran, Brendan J; Marshall, Vikki M; de Graaf, Carolyn; Drysdale, Karen E; Shabbar, Meriam; Smyth, Gordon K; Corbin, Jason E; Alexander, Warren S; Foote, Simon J

    2009-02-01

    Platelets play a critical role in the pathogenesis of malarial infections by encouraging the sequestration of infected red blood cells within the cerebral vasculature. But platelets also have well-established roles in innate protection against microbial infections. We found that purified human platelets killed Plasmodium falciparum parasites cultured in red blood cells. Inhibition of platelet function by aspirin and other platelet inhibitors abrogated the lethal effect human platelets exert on P. falciparum parasites. Likewise, platelet-deficient and aspirin-treated mice were more susceptible to death during erythrocytic infection with Plasmodium chabaudi. Both mouse and human platelets bind malarial-infected red cells and kill the parasite within. These results indicate a protective function for platelets in the early stages of erythrocytic infection distinct from their role in cerebral malaria.

  19. 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)

  20. 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

  1. Effect of Jin-3-Needling Therapy on Plasma Corticosteroid, Adrenocorticotrophic Hormone and Platelet 5-HT Levels in Patients with Generalized Anxiety Disorder

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective:To observe the therapeutic efficacy of Jin-3-needling therapy(J3N)on generalized anxiety disorder(GAD)through clinical global impression scale(CGI),and to explore the mechanism by measuring the plasma levels of corticosteroid(CS),adrenocorticotrophic hormone (ACTH),and platelet 5-hydroxytryptamine(5-HT)before and after treatment.Methods:Eightysix GAD patients with the diagnosis agreeing with the inclusion criteria were assigned,according to the sequence of visiting time,to three groups.The 29 patients in the Western medicine group were treated mainly with fluoxetine or paroxetine,Alprazolam might be given additionally in severe conditions if necessary;the 29 patients in the needling group received J3N therapy with Sishenzhen,Dingshenzhen,Neiguan(PC6),Shenmen(HT7)and Sanyinjiao(SP6)as the chief acupoints selected;and the 28 patients in the combined treatment group were treated with both drugs and needling in the same way as applied in the above two groups.The therapeutic course for all was 6weeks.Conditions of patients were evaluated before and after treatment with CGI,and levels of CS,ACTH as well as 5-HT were measured by high performance liquid chromatography-electrochemistry.Results:By CGI scoring,the scores of severity index and the general index were not different significantly in the three groups,but the efficacy index proved to be the highest in the needling group,the second in the combined trentment group,and the lowest in the drug group.Plasma level of ACTH and platelet content of 5-HT were lowered in all the three groups after treatment,showing statistical significance(P<0.05),but no significant change was found in CS level(P>0.05).Conclusion:The therapeutic efficacy of J3N in treating GAD is equivalent to,but with the efficacy index significantly higher than,that of conventional treatment.Moreover,when combined with drugs,needling might effectively prevent the side effect of the routinely used Western drugs.The regulatory action of needling

  2. 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...

  3. Raman Tweezers as a Diagnostic Tool of Hemoglobin-Related Blood Disorders

    Directory of Open Access Journals (Sweden)

    Giulia Rusciano

    2008-12-01

    Full Text Available This review presents the development of a Raman Tweezers system for detecting hemoglobin-related blood disorders at a single cell level. The study demonstrates that the molecular fingerprint insight provided by Raman analysis holds great promise for distinguishing between healthy and diseased cells in the field of biomedicine. Herein a Raman Tweezers system has been applied to investigate the effects of thalassemia, a blood disease quite diffuse in the Mediterranean Sea region. By resonant excitation of hemoglobin Raman bands, we examined the oxygenation capability of normal, alpha- and beta-thalassemic erythrocytes. A reduction of this fundamental red blood cell function, particularly severe for beta-thalassemia, has been found. Raman spectroscopy was also used to draw hemoglobin distribution inside single erythrocytes; the results confirmed the characteristic anomaly (target shape, occurring in thalassemia and some other blood disorders. The success of resonance Raman spectroscopy for thalassemia detection reported in this review provide an interesting starting point to explore the application of a Raman Tweezers system in the analysis of several blood disorders.

  4. 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 ...

  5. 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.

  6. Evaluation of Chromosomal Disorders in Tissue and Blood Samples in Patients with Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    A. Parvaneroo

    2004-12-01

    Full Text Available Statement of Problem: Many studies have indicated that genetic disturbances are common findings in patients with Oral Squamous Cell Carcinoma (OSCC. Identification of these changes can be helpful in diagnostic procedures of these tumors.Purpose: The aim of this study was to appraise the chromosomal disorders in blood and tissue patients with OSCC.Methods and Materials: In this descriptive study, the study group consisted of all OSCC patients who were referred to the Faculty of Dentistry, Tehran University of Medical Sciences, Maxillofacial Surgery Clinic of Shariati Hospital, and Amir Aalam Hospital fromSeptember 2000 to November 2002. In order to study chromosomal disorders in the peripheral blood lymphocytes, 5 mL of blood was obtained from each patient In patients with the large lesion, a piece of involved tissue were obtained and cultured for 24 hours.This led to 29 blood samples and 16 tissue specimens and any relation between OSCC and age, sex, smoking and alcohol use were evaluated.Results: In this study, OSCC was more common in males than in females (3 to 5. 31% of our patients were smokers, and one had a history of alcoholic consumption. There was an increase in incidence of OSCC with age. In this study, all patients had numerical(aneuploidy, polyploidy and structural chromosomal disorders (double minute, fragment,breakage and dicentric. There was significant difference between blood and tissue chromosomal disorders (aneuploidy, polyploidy,breakage in OSCC patients.Conclusion: It can be concluded that chromosomes in patients with OSCC might show some genetic aberration and evaluation of involved tissue might be better way for determining this disorders.

  7. Platelet MicroRNAs: An Overview.

    Science.gov (United States)

    Dahiya, Neetu; Sarachana, Tewarit; Vu, Long; Becker, Kevin G; Wood, William H; Zhang, Yongqing; Atreya, Chintamani D

    2015-10-01

    MicroRNAs (miRNAs) are short ~22-nucleotide noncoding RNA that have been found to influence the expression of many genes and cellular processes by either repressing translation or degrading messenger RNA transcripts. Platelet miRNA expression has been shown to be perturbed during ex vivo storage of platelets and in platelet-associated disorders. Although bioinformatics-based miRNA target predictions have been established, direct experimental validation of the role of miRNAs in platelet biology has been rather slow. Target prediction studies are, nonetheless, valuable in directing the design of appropriate experiments to test specific miRNA:messenger RNA interactions relevant to the underlying mechanisms of platelet function in general and in disease as well as in ex vivo storage-associated "storage lesions," a collective term used to include physiologic, biochemical, and morphologic changes that occur in stored platelets. This brief review will focus on emerging human platelet miRNA studies to emphasize their potential role relevant to transfusion medicine field in terms of regulating platelet signaling pathways, markers of platelet associated disorders, and remote impactors of gene expression (intercellular biomodulators) as well as potential platelet quality markers of storage and pathogen reduction treatments.

  8. [Disturbances of blood lipid content after acute disorders of brain blood flow].

    Science.gov (United States)

    Ivanova, N E; Lebedev, I A; Akinina, S A; Anishchenko, L I; Koltsov, V V; Beliavskiĭ, A R; Sokolova, A A; Iakovlev, S V

    2011-01-01

    The parameters of blood lipid spectrum have been analyzed in 421 patients who survived cerebral stroke and transitory ischemic attacks in 2004-2008. The study included people of Khanty-Mansiysk and Khanty-Mansi autonomous okrug and watchmen. The statistical analysis did not reveal differences between mean concentrations of total cholesterol, high and low density lipoproteins and triglycerides in the settled population and in watchmen. Mean values of all parameters, with the exception of high-density lipoprotein, were higher compared to normative values. The highest frequency of deviations was found for low-density lipoproteins (63.5% of cases). The highest concentrations of total cholesterol and low-density proteins were seen in patients after transitory ischemic attacks regardless of their sex. The comparison of blood lipid spectrum parameters in different age groups revealed significant differences only for total cholesterol.

  9. 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.

  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. Platelet mechanosensing of collagen matrices.

    Directory of Open Access Journals (Sweden)

    Matthew F Kee

    Full Text Available During vascular injury, platelets adhere to exposed subendothelial proteins, such as collagen, on the blood vessel walls to trigger clot formation. Although the biochemical signalings of platelet-collagen interactions have been well characterized, little is known about the role microenvironmental biomechanical properties, such as vascular wall stiffness, may have on clot formation. To that end, we investigated how substrates of varying stiffness conjugated with the same concentration of Type I collagen affect platelet adhesion, spreading, and activation. Using collagen-conjugated polyacrylamide (PA gels of different stiffnesses, we observed that platelets do in fact mechanotransduce the stiffness cues of collagen substrates, manifesting in increased platelet spreading on stiffer substrates. In addition, increasing substrate stiffness also increases phosphatidylserine exposure, a key aspect of platelet activation that initiates coagulation on the platelet surface. Mechanistically, these collagen substrate stiffness effects are mediated by extracellular calcium levels and actomyosin pathways driven by myosin light chain kinase but not Rho-associated protein kinase. Overall, our results improve our understanding of how the mechanics of different tissues and stroma affect clot formation, what role the increased vessel wall stiffness in atherosclerosis may directly have on thrombosis leading to heart attacks and strokes, and how age-related increased vessel wall stiffness affects hemostasis and thrombosis.

  12. 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

  13. 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),

  14. 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.

  15. 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

  16. Glycoprotein Ibα clustering in platelet storage and function

    NARCIS (Netherlands)

    Gitz, E.

    2013-01-01

    Platelets are anucleated, discoid-shaped cells that play an essential role in the formation of a hemostatic plug to prevent blood loss from injured vessels. Initial platelet arrest at the damaged arterial vessel wall is mediated through the interaction between the platelet receptor glycoprotein (GP)

  17. 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...

  18. Platelet-TLR7 mediates host survival and platelet count during viral infection in the absence of platelet-dependent thrombosis.

    Science.gov (United States)

    Koupenova, Milka; Vitseva, Olga; MacKay, Christopher R; Beaulieu, Lea M; Benjamin, Emelia J; Mick, Eric; Kurt-Jones, Evelyn A; Ravid, Katya; Freedman, Jane E

    2014-07-31

    Viral infections have been associated with reduced platelet counts, the biological significance of which has remained elusive. Here, we show that infection with encephalomyocarditis virus (EMCV) rapidly reduces platelet count, and this response is attributed to platelet Toll-like receptor 7 (TLR7). Platelet-TLR7 stimulation mediates formation of large platelet-neutrophil aggregates, both in mouse and human blood. Intriguingly, this process results in internalization of platelet CD41-fragments by neutrophils, as assessed biochemically and visualized by microscopy, with no influence on platelet prothrombotic properties. The mechanism includes TLR7-mediated platelet granule release, translocation of P-selectin to the cell surface, and a consequent increase in platelet-neutrophil adhesion. Viral infection of platelet-depleted mice also led to increased mortality. Transfusion of wild-type, TLR7-expressing platelets into TLR7-deficient mice caused a drop in platelet count and increased survival post EMCV infection. Thus, this study identifies a new link between platelets and their response to single-stranded RNA viruses that involves activation of TLR7. Finally, platelet-TLR7 stimulation is independent of thrombosis and has implications to the host immune response and survival.

  19. 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.

  20. 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...

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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...

  7. 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.

  8. 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...

  9. Stability of lyophilized human platelets loaded with small molecule carbohydrates.

    Science.gov (United States)

    Wang, J X; Yang, C; Wan, W; Liu, M X; Ren, S P; Quan, G B; Han, Y

    2011-01-01

    Long-term preservation of platelets is a great challenge for blood transfusion centers, due to the required narrow storage temperature arange (22 ± 2 degree C). Short shelf life and potential bacterial growth often lead to the shortage of high-quality platelets. Freeze-dried preservation is thus believed to be a potential solution for long-term platelet storage without losing the hemostasis function. Here we report a new platelet preservation method, which uses small molecule carbohydrates to extend storage time and to maintain platelet function. The activities of lyophilized platelets that were stabilized with small molecule carbohydrate (e.g., cell viability, mean platelet volume, activation characteristics, and aggregation kinetics) were maintained after storage of 30, 60, and 90 days at room temperature, 4 degree C, and -20 degree C. The recovery of freeze-dried platelets was 87 percent in comparison to fresh platelets. The mean platelet volume of rehydrated platelets increased (from 6.8 fl to 8.0 fl). About 40 percent of rehydrated platelets was in the early-activated stage (PCA-1 positive) and 30 percent was in the terminal-activated stage (CD62P positive). The cell viability was about 60 percent as measured with CMFDA vital probes. The aggregation rate of rehydrated platelets after 90-day storage was similar to fresh platelets stored at 22 degree C ± 2 degree C.

  10. Platelets and erythrocyte-bound platelets bind infectious HIV-1 in plasma of chronically infected patients.

    Science.gov (United States)

    Beck, Zoltan; Jagodzinski, Linda L; Eller, Michael A; Thelian, Doris; Matyas, Gary R; Kunz, Anjali N; Alving, Carl R

    2013-01-01

    Chronic HIV-1 infection is associated with persistent viremia in most patients, but it remains unclear how free virus may survive the potential hostile effects of plasma. We investigated whether sites might exist on the surfaces of circulating blood cells for protection of infectious HIV-1 particles. Red blood cells (RBC) either from blood of uninfected normal individuals, or from blood obtained without EDTA from chronically infected HIV-1 patients, invariably contained a small number of RBC having attached platelets as determined by flow cytometry, light microscopy, and immunofluorescence microscopy. After mixing normal RBC with platelet-rich plasma, discrete populations of RBC, platelets, and complexes of platelets attached to RBC were purified by fluorescence-activated cell sorting. Upon incubation of purified cells or platelets with HIV-1 followed by washing and co-incubation with CD4-positive peripheral blood mononuclear cells (PBMC), platelets, and platelet-RBC complexes, but not platelet-free RBC, caused infection of PBMC. Infection was prevented by pre-treating the platelet-RBC complexes with EDTA. Plasma and RBC (comprising a RBC/platelet-RBC mixture) from chronically infected patients with low viral loads were also co-incubated with PBMC ex vivo to determine the presence of infectious HIV-1. All freshly isolated plasmas from the HIV-1-infected donors, obtained in the absence of anticoagulant, were noninfectious. Interestingly, the RBC from most of the patients caused cell-cell infection of PBMC that was prevented by stripping the RBC with EDTA. A monoclonal antibody to DC-SIGN partially inhibited cell-cell HIV-1 infection of PBMC by normal RBC pre-incubated with platelets and HIV-1. We conclude: (a) platelet-free EDTA-free plasma from chronically infected HIV-1 patients, although containing viral RNA, is an environment that lacks detectable infectious HIV-1; (b) platelets and platelet-RBC complexes, but not purified RBC, bind infectious HIV-1; (c) DC

  11. Platelets and erythrocyte-bound platelets bind infectious HIV-1 in plasma of chronically infected patients.

    Directory of Open Access Journals (Sweden)

    Zoltan Beck

    Full Text Available Chronic HIV-1 infection is associated with persistent viremia in most patients, but it remains unclear how free virus may survive the potential hostile effects of plasma. We investigated whether sites might exist on the surfaces of circulating blood cells for protection of infectious HIV-1 particles. Red blood cells (RBC either from blood of uninfected normal individuals, or from blood obtained without EDTA from chronically infected HIV-1 patients, invariably contained a small number of RBC having attached platelets as determined by flow cytometry, light microscopy, and immunofluorescence microscopy. After mixing normal RBC with platelet-rich plasma, discrete populations of RBC, platelets, and complexes of platelets attached to RBC were purified by fluorescence-activated cell sorting. Upon incubation of purified cells or platelets with HIV-1 followed by washing and co-incubation with CD4-positive peripheral blood mononuclear cells (PBMC, platelets, and platelet-RBC complexes, but not platelet-free RBC, caused infection of PBMC. Infection was prevented by pre-treating the platelet-RBC complexes with EDTA. Plasma and RBC (comprising a RBC/platelet-RBC mixture from chronically infected patients with low viral loads were also co-incubated with PBMC ex vivo to determine the presence of infectious HIV-1. All freshly isolated plasmas from the HIV-1-infected donors, obtained in the absence of anticoagulant, were noninfectious. Interestingly, the RBC from most of the patients caused cell-cell infection of PBMC that was prevented by stripping the RBC with EDTA. A monoclonal antibody to DC-SIGN partially inhibited cell-cell HIV-1 infection of PBMC by normal RBC pre-incubated with platelets and HIV-1. We conclude: (a platelet-free EDTA-free plasma from chronically infected HIV-1 patients, although containing viral RNA, is an environment that lacks detectable infectious HIV-1; (b platelets and platelet-RBC complexes, but not purified RBC, bind infectious HIV

  12. 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...

  13. Analysis of Red Blood Cell Spill over in Platelet Apheresis Collection%机采血小板红细胞混入量超标原因分析

    Institute of Scientific and Technical Information of China (English)

    侯晓岩; 张轶

    2012-01-01

    Objective Proper process controls should be applied to decrease percentage of red blood cell spill over, to avoid loss of platelet products, and to maintain a high quality of platelet apheresis collection. Methods Using a statistical method to analyze 33 cases of red cell spill over tested out of the total 18019 platelet apheresis products in Taiyuan Blood Center from 2005 to 2009. Results Red cell spill over is related to the process of platelet apheresis collection and the maintenance condition of relevant machine. Conclusion Good pre-screening based on practical experience as a first pass, excellent technical operation to ensure whole collection process and careful maintenance of apheresis machine could help minimize the chance of red cell spill over and guarantee the effectiveness of platelets product.%目的 在机采血小板采集工作中采取相应措施,减少产品冲红几率,避免制品在二次分离出红细胞的同时丢失血小板,确保机采血小板的质量.方法 通过对2005 ~ 2009年太原血液中心机采血小板18019人次中33例红细胞混入量超标的原因经统计学处理进行分析.结果 献血者的筛选、操作人员技术的熟练程度、仪器设备是否处于良好的运行状态与血小板制品的冲红有关.结论 根据实际工作经验力争在献血者筛选上把好第一关,在仪器设备的维护保养上做到细致到位,在工作人员操作技术上做到精益求精,将血小板制品冲红几率降到最低,确保机采血小板的有效成分.

  14. Differences in non-MHC restricted cytotoxic activities of human peripheral blood lymphocytes after transfusion with allogeneic leukocytes or platelets possessing class I and/or class II MHC molecules.

    Science.gov (United States)

    Pócsik, E; Mihalik, R; Réti, M; Gyódi, E; Pálóczi, K; Mayer, K; Kassai, M; Herold, M; Huber, C; Petrányi, G G

    1990-12-01

    MHC-unrestricted cytotoxic activity of peripheral blood lymphocytes (PBL) from 4-6 healthy donors was investigated before and after transfusion with allogeneic leukocytes or platelets. Natural killer and lectin-dependent cellular cytotoxicity (LDCC) of PBL was tested against K562 and Raji target cells in a 4-h and 16-h 51Cr-release assay, respectively. After allotransfusion with leukocytes, we found increased cytotoxic activity of each donor's PBL against all the three targets on day 3 or 7. The highest non-specific cytotoxic activity was detected against the relatively NK resistant Raji target cells. The increase of cytotoxic activity was lowest against the LDCC target (PHA-treated Raji) cells. On the contrary, no changes in cytotoxic activity against any targets were observed after allotransfusion with platelets (possessing class I HLA antigens but no HLA class II molecules). Our results suggest that HLA class II molecules, presumably by inducing immune responses, are essential for activation/generation of non-specific killing of tumor targets after leukocyte transfusion. Thrombocytes, known to be less immunogenic than leukocytes, are not effective in in vivo enhancing of non-specific cytotoxicity. Cellular activation of PBL following leukocyte allotransfusion was confirmed by detection of elevated serum neopterin and beta-2-microglobulin levels on day 3. This was not the case after platelet allotransfusion. In addition, the expression of ICAM-1 antigen (as a molecule involved directly in MHC-unrestricted cytotoxicity) was also found to be increased in two donors' PBL on day 3 after leukocyte transfusion in contrast to transfusion with platelets.

  15. 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

  16. Treatment of immune thrombocytopenia after allogeneic cord blood stem cell transplantation with rituximab: a case report

    Institute of Scientific and Technical Information of China (English)

    Mengxing Li; Jishi Wang; Yan Zhang; Zhiqiang Sun; Yanju Li; Xiaoli Zhou

    2013-01-01

    Immune thrombocytopenia (ITP) is a chronic disease resulting from increased platelet destruction and impaired platelet production. Secondary ITP can be a manifestation of chronic graft-versus-host disease (GVHD) and represent a lymphoproliferative disorder. A boy with chronic graft-versus-host disease after cord blood stem cell transplantation who had severe refractory immune-mediated thrombocytopenia received infusion of rituximab weekly, 375 mg/m2, for 4 weeks. Platelets count of the patient was recovered, and rituximab was well tolerated with no severe toxicity observed during treatment.

  17. Pooled platelet concentrates: an alternative to single donor apheresis platelets?

    Science.gov (United States)

    Pietersz, R N I

    2009-10-01

    Three types of platelet concentrates (PC) are compared: PC either processed with the platelet-rich plasma (PRP) or the Buffy coat (BC) method from whole blood units and PC obtained by apheresis. Leuko-reduction (LR) pre-storage is advocated to improve quality of the PC during storage and reduce adverse reactions in recipients. Standardization of methods allow preparation of PC with comparable yields of approximately 400 x 10(9) platelets in pooled non-LR-PRP, approximately 370 x 10(9) in pooled LR-BC-PC and in LR apheresis PC the number of platelets can be targeted on 350 x 10(9) or more with devices of various manufacturers. While viral transmission can be prevented by outstanding laboratory tests, the risk of bacterial contamination should be reduced by improved arm disinfection, deviation of the first 20-30 ml of blood and culture or rapid detection assays of the PC pre-issue. In a large prospective multicenter trial no significant difference was observed between cultures of apheresis PC (n = 15,198): 0.09% confirmed positive units versus 0.06% in pooled BC-PC (n = 37,045), respectively. Though platelet activation as measured by CD62 expression may differ in vitro in PC obtained with various apheresis equipment, and also between PC processed with the two whole blood methods there is scarce literature about the clinical impact of these findings. In conclusion the final products of LR-PC derived from whole blood or obtained by apheresis can be comparable, provided the critical steps of the processing method are identified and covered and the process is in control.

  18. 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)

  19. 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

  20. The prowess of platelets in immunity and inflammation.

    Science.gov (United States)

    Koenen, Rory R

    2016-09-27

    Platelets not only serve as essential haemostatic cells, they also have important roles in immune defence and inflammation. Despite not having a nucleus, platelets contain physiologically relevant amounts of RNA, which can be spliced and translated into functional proteins. In addition, platelets have the ability to bind to numerous other cells, such as leukocytes and vascular cells. During those interactions, platelets can modulate cellular responses, resulting in e. g. inflammatory activation or apoptosis. Recent studies have demonstrated that platelets can influence the outcomes of bacterial and viral infection, as well as the extent of tissue injury after ischaemia. Platelets also carry considerable amounts of cytokines and growth factors in their secretory granules, preformed for rapid secretion. Those properties in combination with the sheer amount of platelets circulating in the blood stream make them an important force in the immune response during health and disease. In this overview, recent findings concerning those interesting properties of platelets beyond haemostasis are discussed.

  1. Insights into Platelet Storage and the Need for Multiple Approaches.

    Science.gov (United States)

    Handigund, Mallikarjun; Cho, Yong Gon

    2015-01-01

    Upon accidental injury and the treatment of many diseases, patients may need a transfusion of blood components in order to achieve hemostasis. Platelets are small enucleated cells derived from bone marrow megakaryocytes that undergo change upon activation at sites of vascular injury and play a vital role in vascular repair and antimicrobial host defense, collectively contributing to hemostasis. They are the common blood components transfused whenever there is need, but supplies do not equal the demand as platelets are required in many medical and surgical procedures. In addition, surplus supplies of platelet concentrate are often discarded as they have a short shelf life. Currently, platelet concentrates are stored at room temperature for a maximum of 5 days from the date of collection; the temporal aspect is an added hurdle in the growing demand for platelet concentrates. Many investigations have been carried out in attempt to improve the quality and lengthen the shelf life of platelets, but the few that have succeeded are not commercially viable. Moreover, currently there is a declining trend in platelet research, quelling the hope of platelet storage improvement. Successful strategies would be a boon for medicine in particular and humanity in general. This review deals with past and current efforts toward improving the quality of platelet concentrates by reducing platelet storage lesions and increasing the viable storage period for platelets. Also presented are new perspectives based on past and current efforts, which should be investigated for platelet research in this decade.

  2. Blood Transcriptomic Markers in Patients with Late-Onset Major Depressive Disorder.

    Science.gov (United States)

    Miyata, Shigeo; Kurachi, Masashi; Okano, Yoshiko; Sakurai, Noriko; Kobayashi, Ayumi; Harada, Kenichiro; Yamagata, Hirotaka; Matsuo, Koji; Takahashi, Keisuke; Narita, Kosuke; Fukuda, Masato; Ishizaki, Yasuki; Mikuni, Masahiko

    2016-01-01

    We investigated transcriptomic markers of late-onset major depressive disorder (LOD; onset age of first depressive episode ≥ 50 years) from the genes expressed in blood cells and identified state-dependent transcriptomic markers in these patients. We assessed the genes expressed in blood cells by microarray and found that the expression levels of 3,066 probes were state-dependently changed in the blood cells of patients with LOD. To select potential candidates from those probes, we assessed the genes expressed in the blood of an animal model of depression, ovariectomized female mice exposed to chronic ultra-mild stress, by microarray and cross-matched the differentially expressed genes between the patients and the model mice. We identified 14 differentially expressed genes that were similarly changed in both patients and the model mice. By assessing statistical significance using real-time quantitative PCR (RT-qPCR), the following 4 genes were selected as candidates: cell death-inducing DFFA-like effector c (CIDEC), ribonuclease 1 (RNASE1), solute carrier family 36 member-1 (SLC36A1), and serine/threonine/tyrosine interacting-like 1 (STYXL1). The discriminating ability of these 4 candidate genes was evaluated in an independent cohort that was validated. Among them, CIDEC showed the greatest discriminant validity (sensitivity 91.3% and specificity 87.5%). Thus, these 4 biomarkers should be helpful for properly diagnosing LOD.

  3. Blood Transcriptomic Markers in Patients with Late-Onset Major Depressive Disorder.

    Science.gov (United States)

    Miyata, Shigeo; Kurachi, Masashi; Okano, Yoshiko; Sakurai, Noriko; Kobayashi, Ayumi; Harada, Kenichiro; Yamagata, Hirotaka; Matsuo, Koji; Takahashi, Keisuke; Narita, Kosuke; Fukuda, Masato; Ishizaki, Yasuki; Mikuni, Masahiko

    2016-01-01

    We investigated transcriptomic markers of late-onset major depressive disorder (LOD; onset age of first depressive episode ≥ 50 years) from the genes expressed in blood cells and identified state-dependent transcriptomic markers in these patients. We assessed the genes expressed in blood cells by microarray and found that the expression levels of 3,066 probes were state-dependently changed in the blood cells of patients with LOD. To select potential candidates from those probes, we assessed the genes expressed in the blood of an animal model of depression, ovariectomized female mice exposed to chronic ultra-mild stress, by microarray and cross-matched the differentially expressed genes between the patients and the model mice. We identified 14 differentially expressed genes that were similarly changed in both patients and the model mice. By assessing statistical significance using real-time quantitative PCR (RT-qPCR), the following 4 genes were selected as candidates: cell death-inducing DFFA-like effector c (CIDEC), ribonuclease 1 (RNASE1), solute carrier family 36 member-1 (SLC36A1), and serine/threonine/tyrosine interacting-like 1 (STYXL1). The discriminating ability of these 4 candidate genes was evaluated in an independent cohort that was validated. Among them, CIDEC showed the greatest discriminant validity (sensitivity 91.3% and specificity 87.5%). Thus, these 4 biomarkers should be helpful for properly diagnosing LOD. PMID:26926397

  4. Blood transcriptomic biomarkers in adult primary care patients with major depressive disorder undergoing cognitive behavioral therapy.

    Science.gov (United States)

    Redei, E E; Andrus, B M; Kwasny, M J; Seok, J; Cai, X; Ho, J; Mohr, D C

    2014-09-16

    An objective, laboratory-based diagnostic tool could increase the diagnostic accuracy of major depressive disorders (MDDs), identify factors that characterize patients and promote individualized therapy. The goal of this study was to assess a blood-based biomarker panel, which showed promise in adolescents with MDD, in adult primary care patients with MDD and age-, gender- and race-matched nondepressed (ND) controls. Patients with MDD received cognitive behavioral therapy (CBT) and clinical assessment using self-reported depression with the Patient Health Questionnaire-9 (PHQ-9). The measures, including blood RNA collection, were obtained before and after 18 weeks of CBT. Blood transcript levels of nine markers of ADCY3, DGKA, FAM46A, IGSF4A/CADM1, KIAA1539, MARCKS, PSME1, RAPH1 and TLR7, differed significantly between participants with MDD (N=32) and ND controls (N=32) at baseline (qdepressed. Thus, blood levels of different transcript panels may identify the depressed from the nondepressed among primary care patients, during a depressive episode or in remission, or follow and predict response to CBT in depressed individuals.

  5. 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 ...

  6. A Multicenter study on preparation of Leukodepleted Platelet Concentrates from Pooled whole blood-derived platelets%全血制备浓缩血小板的汇集及滤除白细胞的多中心研究

    Institute of Scientific and Technical Information of China (English)

    王红; 吴瑕; 钟锐; 贺曾; 曹晔; 何语良; 陈洁; 刘嘉馨

    2012-01-01

    Objective To cooperate with a number of blood centers and evaluate the quality of pooled platelet and leukocyte depletion, which aims to supply basis for establishing operating procedures and quality standard of pooled platelet and leukocyte depletion. Methods PCs was prepared from 400 ml fresh whole blood by platelet-rich plasma (PRP) or buffy-coat (BC) method. 10 to 16 units of ABO-matched PCs were pooled, and then filtered with two types of domestic filters (namely group A and B) randomly. The conventional and functional indicators of platelet were evaluated before and after filtering, and the total samples were 202. Results The total of cases that number of platelet was more than 2. 4 × 1011 was 147, including 77 cases in group A and 70 cases in group B. In group A the number of platelet and leukocyte before and after filtering were (2. 90 ±0.45) xlO" 75(2.60±0.43) × 1011 ,(176.45 ±135.67) × 106 VS( 1.00 ±2.29) ×106 respectively ,and in group B the number of platelet and leukocyte before and after filtering were(2. 80 ±0. 36) × 1011 VS(2. 40 ± 0.37) × 1011, (175. 76 ±147. 84) × 106 VS(0. 30 ±0. 72) × 106 respectively. While the total of cases that number of platelet was less than 2. 4 × 1011 was 55, including 29 cases in group A and 26 cases in group B. In group A the number of platelet and leukocyte before and after filtering were (1. 71 ±0.39)×1011 VS( 1.43 ±0.42) × 1011 ,(65. 85 ±110. 97) ×106 VS (3. 7 ±3. 98) × 106 respectively,and in group B the number of platelet and leukocyte before and after filtering were(l. 79 ±0.48) ×1011 VS(1.42±0.46) × 1011 ,(70. 63 ±145. 55) × 106 VS(1. 45 ±2. 66) × 106 respectively. There were no significant difference(P>0. 05) of these indicators such as pH value,hypotonic shock response (HSR) ,CD62p expression ( % ) and platelet aggregation after filtering in group A and B. Conclusion Pooling and filtering platelet concentrates prepared by PRP and BC method can remove leukocyte effectively and

  7. Multiwavelength UV/visible spectroscopy for the quantitative investigation of platelet quality

    Science.gov (United States)

    Mattley, Yvette D.; Leparc, German F.; Potter, Robert L.; Garcia-Rubio, Luis H.

    1998-04-01

    The quality of platelets transfused is vital to the effectiveness of the transfusion. Freshly prepared, discoid platelets are the most effective treatment for preventing spontaneous hemorrhage or for stopping an abnormal bleeding event. Current methodology for the routine testing of platelet quality involves random pH testing of platelet rich plasma and visual inspection of platelet rich plasma for a swirling pattern indicative of the discoid shape of the cells. The drawback to these methods is that they do not provide a quantitative and objective assay for platelet functionality that can be used on each platelet unit prior to transfusion. As part of a larger project aimed at characterizing whole blood and blood components with multiwavelength UV/vis spectroscopy, isolated platelets and platelet in platelet rich plasma have been investigated. Models based on Mie theory have been developed which allow for the extraction of quantitative information on platelet size, number and quality from multi-wavelength UV/vis spectra. These models have been used to quantify changes in platelet rich plasma during storage. The overall goal of this work is to develop a simple, rapid quantitative assay for platelet quality that can be used prior to platelet transfusion to ensure the effectiveness of the treatment. As a result of this work, the optical properties for isolated platelets, platelet rich plasma and leukodepleted platelet rich plasma have been determined.

  8. 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.

  9. P-selectin-mediated platelet adhesion promotes tumor growth.

    Science.gov (United States)

    Qi, Cuiling; Wei, Bo; Zhou, Weijie; Yang, Yang; Li, Bin; Guo, Simei; Li, Jialin; Ye, Jie; Li, Jiangchao; Zhang, Qianqian; Lan, Tian; He, Xiaodong; Cao, Liu; Zhou, Jia; Geng, Jianguo; Wang, Lijing

    2015-03-30

    Blood platelets foster carcinogenesis. We found that platelets are accumulated in human tumors. P-selectin deficiency and soluble P-selectin abolish platelet deposition within tumors, decreasing secretion of vascular endothelial growth factor and angiogenesis, thereby suppressing tumor growth. Binding of the P-selectin cytoplasmic tail to talin1 triggers the talin1 N-terminal head to interact with the β3 cytoplasmic tail. This activates αIIbβ3 and recruits platelets into tumors. Platelet infiltration into solid tumors occurs through a P-selectin-dependent mechanism.

  10. 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.

  11. 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

  12. Evaluation of storage performance of special plastic blood bags for apheresis platelets%血小板保存专用塑料血袋的储存性能评价

    Institute of Scientific and Technical Information of China (English)

    王捷熙; 韩颖; 周倩; 刘敏霞; 王艳; 柴丽娜; 卓海龙; 易晓阳; 周建伟; 王建卫

    2015-01-01

    Objective To evaluate the storage performance of storage bags for apheresis platelets produced by Shandong Weigao Group Medical Polymer Co .,Ltd ( experimental bags ) with Trima set platelet storage bags produced by the U .S. Gambro BCT as the control .Method One unit of apheresis platelets was divided into two equal parts , added to control blood bags and experimental blood bags respectively .All samples were stored at ( 22 ±2 )℃ with consecutive oscillation . The platelets′count, mean volume, aggregate activity (ADP, THR), pH, glucose, lactate concentration, lactate dehydro-genase concentration , hypotonic shock reaction , expression of CD62P and phosphatidyl serine on surface of cell membrane were detected at 0,3,5 and 7 d respectively.Results There was no significant difference in platelet quality after five days of storage between the experimental group and the control group (t-test, P>0.05).Conclusion Two types of platelet stor-age blood bags have similar storage performance for apheresis platelets .%目的:以美国Gambro BCT公司生产的Trima set血小板保存袋为对照,评价山东威高集团医用高分子制品股份有限公司生产的血小板保存袋对单采血小板的储存性能。方法将1U单采血小板平分成两份,分别加入实验血袋和对照血袋中,于血小板恒温振荡保存箱中保存。分别于保存0、3、5、7d取样,比较分析两组的血小板含量和血小板平均体积、pH值、体外聚集活性、氧分压和二氧化碳分压、葡萄糖、乳酸和乳酸脱氢酶浓度、低渗休克反应、血小板活化和凋亡、血小板形态结构及细菌培养试验。结果两种保存袋保存的血小板在保存期内,相同保存时间实验组与对照组之间各项检测结果差异无统计学意义(P>0.05);无菌试验均为阴性。结论国产血小板专用塑料血袋与美国Trima set血小板保存袋对该实验使用的15份单采血小板具有相似的储存性能。

  13. 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

  14. 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...

  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. 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.

  18. 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.

  19. Low-affinity FcγR interactions can decide the fate of novel human IgG-sensitised red blood cells and platelets.

    Science.gov (United States)

    Armour, Kathryn L; Smith, Cheryl S; Turner, Craig P; Kirton, Christopher M; Wilkes, Anthony M; Hadley, Andrew G; Ghevaert, Cedric; Williamson, Lorna M; Clark, Michael R

    2014-03-01

    G1Δnab is a mutant human IgG1 constant region with a lower ability to interact with FcγR than the natural IgG constant regions. Radiolabelled RBCs and platelets sensitised with specific G1Δnab Abs were cleared more slowly from human circulation than IgG1-sensitised counterparts. However, non-destructive splenic retention of G1Δnab-coated RBCs required investigation and plasma radioactivities now suggest this also occurred for platelets sensitised with an IgG1/G1Δnab mixture. In vitro assays with human cells showed that G1Δnab-sensitised RBCs did not cause FcγRI-mediated monocyte activation, FcγRIIIa-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) or macrophage phagocytosis although they did adhere to macrophages. Thus, FcγRII was implicated in the adhesion despite the Δnab mutation reducing the already low-affinity binding to this receptor class. Additional contacts via P-selectin enhance the interaction of sensitised platelets with monocytes and this system provided evidence of FcγRII-dependent activation by G1Δnab. These results emphasise the physiological relevance of low-affinity interactions: It appears that FcγRII interactions of G1Δnab allowed splenic retention of G1Δnab-coated RBCs with inhibitory FcγRIIb binding preventing RBC destruction and that FcγRIIb engagement by G1Δnab on IgG1/G1Δnab-sensitised platelets overcame activation by IgG1. Considering therapeutic blocking Abs, G1Δnab offers lower FcγR binding and a greater bias towards inhibition than IgG2 and IgG4 constant regions.

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

    Energy Technology Data Exchange (ETDEWEB)

    Vallabhajosula, S.; Machac, J.; Badimon, L.; Lipszyc, H.; Goldsmith, S.J.; Fuster, V.

    1985-05-01

    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 37/sup 0/C 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.

  1. Detection of dengue virus in platelets isolated from dengue patients.

    Science.gov (United States)

    Noisakran, Sansanee; Gibbons, Robert V; Songprakhon, Pucharee; Jairungsri, Aroonroong; Ajariyakhajorn, Chuanpis; Nisalak, Ananda; Jarman, Richard G; Malasit, Prida; Chokephaibulkit, Kulkanya; Perng, Guey Chuen

    2009-03-01

    Though thrombocytopenia or dysfunction of platelets is common in dengue virus infection, the role of platelets has not been established. We enrolled 33 hospitalized children with serologically confirmed dengue virus infection. Blood specimens were collected during hospitalization. Platelets and plasma were isolated from the whole blood. Detection of dengue virus in plasma and platelets was carried out by RT-PCR with primers that can differentiate different dengue serotypes simultaneously, and by electron transmission microscopy (EM). Dengue viral RNA was detected in the platelets and plasma by conventional RT-PCR. A significantly higher percentage of dengue viral RNA was detected in platelets than in plasma (p = 0.03). Platelets isolated 5 days after onset of fever were most likely positive for viral RNA. Concurrent infection or co-circulation with multiple dengue serotypes was observed in 12% of patients. Infrequently, negative-stranded dengue viral RNA was detected in platelets and in plasma. Importantly, EM confirmed the presence of dengue viral-like particles inside platelets prepared from dengue patients. Our findings suggest the presence of dengue virus in platelets may be associated with the dysfunction of platelets observed in dengue patients.

  2. 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

  3. The expression levels of platelet adhesive receptors in PRP derived platelet concentrates during storage

    Directory of Open Access Journals (Sweden)

    Fatemeh Nassaji

    2016-04-01

    Full Text Available Background: Major platelet adhesive receptors that contribute significantly to thrombus formation include platelet receptor glycoprotein Ibα (GPIbα of the GPIb-IX-V complex and platelet glycoprotein VI (GPVI. GPIbα plays a crucial role in platelet tethering to sub-endothelial matrix, which initiates thrombus formation at arterial shear rates, whereas GPVI is critically involved in platelets firm adhesion to the site of injury regardless of shear condition. During storage, platelets experience some changes that deleteriously affect the expression levels of platelet receptors, which in turn can alter platelet functional behaviors. Considering the important roles of GPIbα and GPVI in platelet adhesion, it seems that any dramatic changes in the expression levels of these receptors can influence adhesive function of transfused platelets. Thereby examining GPIbα and GPVI expression during the storage of platelet concentrates may provide some useful information about the functional quality of these products after transfusion. Methods: In our experimental study, 5 PRP-platelet concentrates were randomly obtained from Iranian Blood Transfusion Organization (IBTO. All the platelet products met the standard quality assessment based on AABB (American Association of Blood Banks guidelines. Washed platelets were subjected to flowcytometry analysis for the evaluation of GPIbα and GPVI receptor expression in day 1, 3 and 5 after storage. Data were presented as mean fluorescence intensity (MFI and analyzed by Kruskal-Wallis test with Dunn’s multiple comparison test. Results: The GPIbα expression on first day (MFI=86±5.9 was reduced three days after storage (MFI= 69±6.9. The expression levels continued to reduce until day 5 in which GPIbα expression was markedly decreased to (MFI= 61±7.7 (P= 0.0094. GPVI expression on the days 1, 3 and 5 after storage were 20.6±3.3, 24±2.5 and 14±4.9, respectively. The results showed a significant decrease of

  4. C-type natriuretic peptide inhibits leukocyte recruitment and platelet-leukocyte interactions via suppression of P-selectin expression

    Science.gov (United States)

    Scotland, Ramona S.; Cohen, Marc; Foster, Paul; Lovell, Matthew; Mathur, Anthony; Ahluwalia, Amrita; Hobbs, Adrian J.

    2005-10-01

    The multifaceted process of immune cell recruitment to sites of tissue injury is key to the development of an inflammatory response and involved in the pathogenesis of numerous cardiovascular disorders. We recently identified C-type natriuretic peptide (CNP) as an important endothelium-derived mediator that regulates vascular tone and protects against myocardial ischemia/reperfusion injury. Herein, we investigated whether CNP inhibits leukocyte recruitment and platelet aggregation and thereby exerts a potential antiinflammatory influence on the blood vessel wall. We assessed the effects of CNP on leukocyte-endothelial cell interactions in mouse mesenteric postcapillary venules in vivo in animals with high basal leukocyte activation (endothelial nitric oxide synthase knockout mice, eNOS-/-) or under acute inflammatory conditions (induced by interleukin-1 or histamine). CNP suppressed basal leukocyte rolling in eNOS-/- mice in a rapid, reversible, and concentration-dependent manner. These effects of CNP were mimicked by the selective natriuretic peptide receptor-C agonist cANF4-23. CNP also suppressed leukocyte rolling induced by IL-1 or histamine, inhibited platelet-leukocyte interactions, and prevented thrombin-induced platelet aggregation of human blood. Furthermore, analysis of human umbilical vein endothelial cells, leukocytes, and platelets revealed that CNP selectively attenuates expression of P-selectin. Thus, CNP is a modulator of acute inflammation in the blood vessel wall characterized by leukocyte and platelet activation. These antiinflammatory effects appear to be mediated, at least in part, via suppression of P-selectin expression. These observations suggest that endothelial CNP might maintain an anti-atherogenic influence on the blood vessel wall and represent a target for therapeutic intervention in inflammatory cardiovascular disorders. endothelium | natriuretic peptide receptor type C | atherosclerosis | thrombosis

  5. Understanding platelet generation from megakaryocytes: implications for in vitro-derived platelets.

    Science.gov (United States)

    Sim, Xiuli; Poncz, Mortimer; Gadue, Paul; French, Deborah L

    2016-03-10

    Platelets are anucleate cytoplasmic discs derived from megakaryocytes that circulate in the blood and have major roles in hemostasis, thrombosis, inflammation, and vascular biology. Platelet transfusions are required to prevent the potentially life-threatening complications of severe thrombocytopenia seen in a variety of medical settings including cancer therapy, trauma, and sepsis. Platelets used in the clinic are currently donor-derived which is associated with concerns over sufficient availability, quality, and complications due to immunologic and/or infectious issues. To overcome our dependence on donor-derived platelets for transfusion, efforts have been made to generate in vitro-based platelets. Work in this area has advanced our understanding of the complex processes that megakaryocytes must undergo to generate platelets both in vivo and in vitro. This knowledge has also defined the challenges that must be overcome to bring in vitro-based platelet manufacturing to a clinical reality. This review will focus on our understanding of committed megakaryocytes and platelet release in vivo and in vitro, and how this knowledge can guide the development of in vitro-derived platelets for clinical application.

  6. Whole blood BDNF levels in healthy twins discordant for affective disorder: association to life events and neuroticism

    DEFF Research Database (Denmark)

    Trajkovska, V.; Vinberg, M.; Aznar, S.;

    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 protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... experienced three or more recent stressful events (n=26) had decreased whole blood BDNF levels compared to high-risk women with two or less recent stressful events (n=35), 21.6+/-7.0 vs. 18.5+/-4.1 ng/ml, respectively, (p

  7. 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 ...

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. Platelet activation risk index as a prognostic thrombosis indicator.

    Science.gov (United States)

    Zlobina, K E; Guria, G Th

    2016-01-01

    Platelet activation in blood flow under high, overcritical shear rates is initiated by Von Willebrand factor. Despite the large amount of experimental data that have been obtained, the value of the critical shear rate, above which von Willebrand factor starts to activate platelets, is still controversial. Here, we recommend a theoretical approach to elucidate how the critical blood shear rate is dependent on von Willebrand factor size. We derived a diagram of platelet activation according to the shear rate and von Willebrand factor multimer size. We succeeded in deriving an explicit formula for the dependence of the critical shear rate on von Willebrand factor molecule size. The platelet activation risk index was introduced. This index is dependent on the flow conditions, number of monomers in von Willebrand factor, and platelet sensitivity. Probable medical applications of the platelet activation risk index as a universal prognostic index are discussed. PMID:27461235

  13. A Putative Blood-Based Biomarker for Autism Spectrum Disorder-Associated Ileocolitis

    Science.gov (United States)

    Walker, Stephen J.; Beavers, Daniel P.; Fortunato, John; Krigsman, Arthur

    2016-01-01

    Gastrointestinal symptoms are common in children with autism spectrum disorder (ASD). A significant proportion of children with ASD and gastrointestinal symptoms have histologic evidence of ileocolitis (inflammation of the terminal ileum and/or colon). We previously reported the molecular characterization of gastrointestinal biopsy tissue from ASD children with ileocolitis (ASDIC+) compared to anatomically similar inflamed tissue from typically developing children with inflammatory bowel disease (IBD; i.e. Crohn’s disease or ulcerative colitis) and typically developing children with gastrointestinal symptoms but no evidence of gastrointestinal mucosal inflammation (TDIC−). ASDIC+ children had a gene expression profile that, while primarily overlapping with known IBD, had distinctive differences. The present study confirms these findings and replicates this molecular characterization in a second cohort of cases (ASDIC+) and controls (TDIC−). In these two separate case/control mucosal-based cohorts, we have demonstrated overlap of 59 differentially expressed transcripts (DETs) unique to inflamed ileocolonic tissue from symptomatic ASDIC+ children. We now report that 9 of these 59 transcripts are also differentially expressed in the peripheral blood of the second cohort of ASDIC+ children. This set of transcripts represents a putative blood-based biomarker for ASD-associated ileocolonic inflammation. PMID:27767057

  14. 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

  15. 原发性ITP患儿外周血血小板相关抗体和淋巴细胞亚群的变化及临床意义%The Changes and Clinical Significance of Platelet Antibodies and Lymphocyte Subsets in Peripheral Blood of Children with Primary ITP

    Institute of Scientific and Technical Information of China (English)

    常涛涛; 郝国平

    2013-01-01

      目的:观察原发性ITP患儿外周血血小板抗体及淋巴细胞亚群变化,探讨其与ITP的关系及临床意义.方法:采用流式细胞技术检测患儿与正常儿童外周血血小板相关抗体(PAIgA、G、M)水平及淋巴细胞亚群(CD3+、CD3+CD4+、CD3+CD8+、CD4+/CD8+、CD19+、CD3-CD(16+56)+)水平.结果:新诊断ITP组与持续性ITP组PAIg(G、M)水平明显高于正常儿童(P<0.001);新诊断性ITP组与持续性ITP组和对照组比较,CD3+T细胞、CD4+/CD8+T细胞比值、CD3-CD(16+56)+NK细胞降低,CD3+CD8+T细胞、CD19+B细胞升高,差异均有统计学意义(P<0.05).结论:原发性ITP患儿存在细胞免疫和体液免疫紊乱,血小板相关抗体和淋巴细胞亚群水平检测的联合使用对原发性ITP的诊断、疗效评估有较好的实用价值.%Objective:To observe the changes of platelet antibodies and lymphocyte subsets in peripheral blood of children with ITP. To investigate the relationship between the changes and ITP,as well as clinical significance. Method:The flow cytometry was used to detect the level of platelet antibody (PAIgA,G,M)and lymphocyte subsets(CD3+、CD3+CD4+,CD3+CD8+,CD4+/CD8+,CD19+,CD3-CD(16+56)+)in peripheral blood of children with primary ITP and healthy children. Result:Newly diagnosed and persistent ITP patients’ platelet antibodies(PAIgA,G,M)was significantly higher than that of normal children(P<0.001). Newly diagnosed and persistent ITP patients’ CD3+T cell,CD4+/CD8+T cell,CD3-CD(16+56)+NK cells was lower than that of normal children. CD3+CD8+T cell、CD19+B cell was higher and the difference was statistically significant(P<0.05). Conclusion:Children with primary ITP existed cell immunity and humoral immune disorders. Platelet antibodies combined with lymphocyte subsets has good practical value to the diagnosis and curative effect evaluation of primary ITP.

  16. 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.

  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. 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.

  20. Significance and changes of peripheral blood, placental tissue cytokines and NO in patients with hypertensive disorders of pregnancy

    Institute of Scientific and Technical Information of China (English)

    Jie-Ning Zou; Li Xiong; Jin-Tao Zhou

    2015-01-01

    Objective:To investigate significance and changes of placental tissue cytokines and NO levels in peripheral blood of patients with hypertensive disorders of pregnancy and their relationship. Methods: A total of 75 cases of hypertensive disorders of pregnancy were selected as researching objects, including 26 cases of pregnancy-induced hypertension subgroup, 29 cases of patients with mild preeclampsia and 20 cases of subgroups severe preeclampsia subgroups;another 45 cases of healthy pregnant women were also selected as the control group. The maternal blood and placental tissue factor (TNF-α, IL-6, hs-CRP) and NO levels of the four groups were compared.Results:Peripheral blood and placental tissue cytokine levels of patients with hypertensive disorders of pregnancy were significantly higher, NO levels were significantly lower than the control group (P<0.01). In subgroups peripheral blood and placenta cytokine levels were gradually increased, NO levels were increased with gestational hypertension disease degree (P<0.05); NO was significantly negatively correlated with TNF-α, IL-6, hs-CRP levels (P<0.01).Conclusions: During pregnancy, monitoring of TNF-α, IL-6, hs-CRP and NO in placental tissue is helpful in prediction and evaluation of early hypertensive disorders of pregnancy, and is also helpful in treatment.

  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 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.

  3. 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

  4. Assessment of quality of platelets preserved in plasma and platelet additive solution: A Malaysian experience

    Directory of Open Access Journals (Sweden)

    Munirah Binti Mokhtar

    2016-01-01

    Full Text Available Background: A use of platelet additives solution (PAS improves storage conditions so as to give increased shelf life to platelets and to maintain hemostatic function. Objective: The present study was aimed to compare in vitro quality of platelet rich plasma (PRP-derived platelet concentrate (PC during extended period of storage in plasma and in additive solution (Composol PS and Fresenius. Study Design: Randomized 19 PCs each were used in the study for plasma and PAS as the storage medium. The measurement parameters, including pH, total white blood cell (WBC count, total platelet count, and platelet activation rate, were studied on day 1, day 5, and day 8 of the storage period. The sterility test was carried out on the eighth day of storage. Results: pH of PC suspended in PAS was significantly lower as compared to that in plasma (P < 0.001 for all the three days of sampling. The WBC count, both in plasma and in PAS, showed an acceptable values of being <0.2 Χ 10 9 /unit during the storage period. Platelet count in PAS was higher as compared to that in plasma, though it was not statistically significant. While both the groups showed increased platelet activation rate during the storage, the PCs suspended in PAS showed significantly higher platelet activation rate (p0.001. Results from sterility test showed no bacterial growth in the PCs in both the groups. Conclusion: Most parameters studied on platelet storage in suspending medium of native plasma and PAS remained well within the acceptable limits. However, the pH values and platelet activation rate significantly differed in PAS as compared with plasma.

  5. 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

  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. Inhibition of amikacin on platelet aggregation and blood coagulation%丁胺卡那霉素对血小板聚集和凝血功能的抑制作用

    Institute of Scientific and Technical Information of China (English)

    费鲜明; 周永列; 邱莲女; 吴建国; 张可

    2010-01-01

    Objective To observe the inhibition of amikacin in vitro on platelet aggregation and blood coagulation tests, and to study its effects on hemostasis and the related mechanisms.Methods Plateletrich plasma and platelet-poor plasma from donors were mixed with different concentration of amikacin, which was divided into four groups:0 mg/L, 30 mg/L, 91 mg/L and 910 mg/L group.The maximial ratio of platelet aggregation induced by ADP were measured with Platelet Aggregation Analyzer.The expression levels of P-selectin, GP Ⅱ b/Ⅲ a and Fg-R were determined with Flow Cytometer.The PT, APTT, TT and Fg of platelet-poor plasma were detected with Blood Coagulation Analyzer. The four concentration of amikacin mentioned above and two anticoagulants (62.5 U/ml of sodium heparin and 109 mmol/L of sodium citrate)were interacted with fresh whole blood, in which the blood CT and plasma Ca2+ were detected. Blood samples were collected from 10 patients with acute lower respiratory tract infection before and 30 minutes after routine amikcin treatment respectively.The maximial ratio of platelet aggregation, the expression levels of P-selectin, GPⅡ b/Ⅲa and Fg-R induced by ADP were measured; while PT, APTT, CT and plasma Ca2+ were determined.Results At 30 mg/L of amikacin group, the maximal ratios of platelet aggregation (65.8±3.9)%, the expression levels of P-selectin (9.2 ± 1.0)% and Fg-R (12.6 ± 1.7)% were statistically lower than those [(88.0 ±4.6%, (16.1 ± 1.3)% and (31.0 ±2.5)%]at 0 mg/L of amikacin group ( t = 9.442,8.432,9.993,P < 0.01 ).At 30 mg/L of amikacin group, the APTT (80.5 ±6.8) s and CT ( 857 ± 66) s were significantly higher than those [(33.0 ± 3.6) s and (447 ± 35 ) s] at 0 mg/L of amikacin group ( t = 11.312, 13.211, P < 0.01 ). There was a negative correlation between amikacin concentration and maximial ratio of platelet aggregation ( r = - 0.832, P < 0.05 ), but a positive correlation between amikacin concentration and inhibitory rates of

  8. 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.

  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. 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.

  11. 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.

  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. BLOOD-BRAIN BARRIER DYSFUNCTION IN DISORDERS OF THE DEVELOPING BRAIN

    Directory of Open Access Journals (Sweden)

    Raffaella eMoretti

    2015-02-01

    Full Text Available ABSTRACTDisorders of the developing brain represent a major health problem. The neurological manifestations of brain lesions can range from severe clinical deficits to more subtle neurological signs or behavioral problems and learning disabilities, which often become evident many years after the initial damage. These long-term sequelae are due at least in part to central nervous system immaturity at the time of the insult.The blood brain barrier (BBB protects the brain and maintains homeostasis. BBB alterations are observed during both acute and chronic brain insults. After an insult, excitatory amino acid neurotransmitters are released, causing reactive oxygen species (ROS-dependent changes in BBB permeability that allow immune cells to enter and stimulate an inflammatory response.The cytokines, chemokines and other molecules released as well as peripheral and local immune cells can activate an inflammatory cascade in the brain, leading to secondary neurodegeneration that can continue for months or even years and finally contribute to post-insult neuronal deficits. The role of the BBB in perinatal disorders is poorly understood. The inflammatory response, which can be either acute (e.g. perinatal stroke, traumatic brain injury or chronic (e.g. perinatal infectious diseases actively modulates the pathophysiological processes underlying brain injury. We present an overview of current knowledge about BBB dysfunction in the developing brain during acute and chronic insults, along with clinical and experimental data.

  14. 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.)

  15. Blood diagnostic biomarkers for major depressive disorder using multiplex DNA methylation profiles: discovery and validation.

    Science.gov (United States)

    Numata, Shusuke; Ishii, Kazuo; Tajima, Atsushi; Iga, Jun-ichi; Kinoshita, Makoto; Watanabe, Shinya; Umehara, Hidehiro; Fuchikami, Manabu; Okada, Satoshi; Boku, Shuken; Hishimoto, Akitoyo; Shimodera, Shinji; Imoto, Issei; Morinobu, Shigeru; Ohmori, Tetsuro

    2015-01-01

    Aberrant DNA methylation in the blood of patients with major depressive disorder (MDD) has been reported in several previous studies. However, no comprehensive studies using medication-free subjects with MDD have been conducted. Furthermore, the majority of these previous studies has been limited to the analysis of the CpG sites in CpG islands (CGIs) in the gene promoter regions. The main aim of the present study is to identify DNA methylation markers that distinguish patients with MDD from non-psychiatric controls. Genome-wide DNA methylation profiling of peripheral leukocytes was conducted in two set of samples, a discovery set (20 medication-free patients with MDD and 19 controls) and a replication set (12 medication-free patients with MDD and 12 controls), using Infinium HumanMethylation450 BeadChips. Significant diagnostic differences in DNA methylation were observed at 363 CpG sites in the discovery set. All of these loci demonstrated lower DNA methylation in patients with MDD than in the controls, and most of them (85.7%) were located in the CGIs in the gene promoter regions. We were able to distinguish patients with MDD from the control subjects with high accuracy in the discriminant analysis using the top DNA methylation markers. We also validated these selected DNA methylation markers in the replication set. Our results indicate that multiplex DNA methylation markers may be useful for distinguishing patients with MDD from non-psychiatric controls.

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

    DEFF Research Database (Denmark)

    Söderström, Anna C; Nybo, Mads; Nielsen, Christian;

    2016-01-01

    BACKGROUND: The results of laboratory analyses are affected by pre-analytical variables, and in particular can platelets be activated by shear handling stress and secrete granular substances. We therefore evaluated the effect of centrifugation speed and time on pre-analytical platelet activation....... 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...... of platelets expressing P-selectin in citrate- and EDTA-plasma centrifuged at 2000 g for 10 min were 43% [interquartile range (IQR), 38%-53%] and 56% (IQR, 31%-78%), respectively (p=0.82). Platelet-rich plasma prepared at 100-250 g for 10 min had significantly lower platelet P-selectin expression (11%-15%), p...

  17. 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.

  18. 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.

  19. 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 ...

  20. 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.

  1. 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.)

  2. Low platelet monoamine oxidase activity in pathological gambling

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, J.L. [Department of Psychiatry, Centro de Salud Mental, Parla Madrid (Spain); Saiz-Ruiz, J. [Department of Psychiatry and Haematology, Hospital Ramon y Cajal, Madrid (Spain); Hollander, E. [Department of Psychiatry, Mount Sinai School of Medicine, Queens Hospital Center, New York (United States); Cesar, J. [Department of Haematology, Hospital Ramon y Cajal, Madrid (Spain); Lopez-Ibor, J.J. Jr. [Department of Psychiatry, Hospital San Carlos, Complutense University, Madrid (Spain)

    1994-12-01

    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.).

  3. Heat shock protein 70 regulates platelet integrin activation, granule secretion and aggregation.

    Science.gov (United States)

    Rigg, Rachel A; Healy, Laura D; Nowak, Marie S; Mallet, Jérémy; Thierheimer, Marisa L D; Pang, Jiaqing; McCarty, Owen J T; Aslan, Joseph E

    2016-04-01

    Molecular chaperones that support protein quality control, including heat shock protein 70 (Hsp70), participate in diverse aspects of cellular and physiological function. Recent studies have reported roles for specific chaperone activities in blood platelets in maintaining hemostasis; however, the functions of Hsp70 in platelet physiology remain uninvestigated. Here we characterize roles for Hsp70 activity in platelet activation and function. In vitro biochemical, microscopy, flow cytometry, and aggregometry assays of platelet function, as well as ex vivo analyses of platelet aggregate formation in whole blood under shear, were carried out under Hsp70-inhibited conditions. Inhibition of platelet Hsp70 blocked platelet aggregation and granule secretion in response to collagen-related peptide (CRP), which engages the immunoreceptor tyrosine-based activation motif-bearing collagen receptor glycoprotein VI (GPVI)-Fc receptor-γ chain complex. Hsp70 inhibition also reduced platelet integrin-αIIbβ3 activation downstream of GPVI, as Hsp70-inhibited platelets showed reduced PAC-1 and fibrinogen binding. Ex vivo, pharmacological inhibition of Hsp70 in human whole blood prevented the formation of platelet aggregates on collagen under shear. Biochemical studies supported a role for Hsp70 in maintaining the assembly of the linker for activation of T cells signalosome, which couples GPVI-initiated signaling to integrin activation, secretion, and platelet function. Together, our results suggest that Hsp70 regulates platelet activation and function by supporting linker for activation of T cells-associated signaling events downstream of platelet GPVI engagement, suggesting a role for Hsp70 in the intracellular organization of signaling systems that mediate platelet secretion, "inside-out" activation of platelet integrin-αIIbβ3, platelet-platelet aggregation, and, ultimately, hemostatic plug and thrombus formation.

  4. 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...

  5. 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...

  6. Cellular origin of platelet-derived microparticles in vivo

    NARCIS (Netherlands)

    A. Rank; R. Nieuwland; R. Delker; A. Köhler; B. Toth; V. Pihusch; R. Wilkowski; R. Pihusch

    2010-01-01

    Introduction: Microparticles (MP), presumably of platelet origin, are the most abundant microparticles in blood. To which extent such MP may also directly originate from megakaryocytes, however, is unknown. During hematopoietic stem cell transplantation, patients undergo total body irradiation which

  7. 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.

  8. The long-term effects of pitavastatin on blood lipids and platelet activation markers in stroke patients: impact of the homocysteine level.

    Directory of Open Access Journals (Sweden)

    Hideki Sugimoto

    Full Text Available To examine the impact of the plasma homocysteine level on the anti-atherosclerotic effects of pitavastatin treatment, we retrospectively examined 59 patients who had a history of stroke and had been prescribed pitavastatin for the treatment of dyslipidemia at the Neurology department of Toho University Ohashi Medical Center Hospital. The patients were classified into two groups according to their homocysteine levels. Carotid artery plaque progression was determined before and after pitavastatin treatment. Plasma levels of high-sensitivity C-reactive protein, platelet molecular markers, and von Willebrand factor were measured. Pitavastatin treatment had beneficial effects on the lipid profiles of these patients and slowed atherosclerosis progression. These effects were observed in both the high and low homocysteine groups. Proactive lipid intervention using pitavastatin may inhibit the progression of atherosclerosis and contribute to secondary prevention of stroke in high-risk patients. We conclude that this statin could inhibit progression at any stage of disease and should therefore be proactively administered to these patient groups, regardless of disease severity.

  9. The novel metalloproteinase atroxlysin-I from Peruvian Bothrops atrox (Jergón) snake venom acts both on blood vessel ECM and platelets.

    Science.gov (United States)

    Sanchez, Eladio F; Schneider, Francisco S; Yarleque, Armando; Borges, Marcia H; Richardson, Michael; Figueiredo, Suely G; Evangelista, Karla S; Eble, Johannes A

    2010-04-01

    We report the isolation and structure-function relationship of a 23kDa metalloproteinase named atroxlysin-I from the venom of the Peruvian Bothrops atrox (Jergón). Atroxlysin is a P-I metalloproteinase and contains 204 residues. Its proteolytic activity towards dimethylcasein is enhanced by Ca2+ but inhibited by EDTA, dithiothreitol, excessive Zn2+ and alpha2-macroglobulin. Unlike other structurally homologous P-I metalloproteinases, atroxlysin-I causes hemorrhages. To examine its hemorrhagic activity mechanistically, we studied its function in vitro and in vivo. It cleaved the Ala14-Leu15 and Tyr16-Leu17 bonds in oxidized insulin B-chain and specifically hydrolyzed the alpha-chains of fibrin(ogen) in a dose- and time-dependent manner. Atroxlysin-I cleaved plasma fibronectin and other extracellular matrix proteins (collagens I and IV) and the triple-helical fragment CB3 of collagen IV, but did not degrade laminin-111. Complementarily, the laminin and collagen binding integrins alpha7beta1 and alpha1beta1 were cleaved by atroxlysin. Even without catalytic activity atroxlysin-I inhibited collagen- and ADP-triggered platelet aggregation. PMID:20102699

  10. 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.

  11. Platelet-derived HMGB1 is a critical mediator of thrombosis.

    Science.gov (United States)

    Vogel, Sebastian; Bodenstein, Rebecca; Chen, Qiwei; Feil, Susanne; Feil, Robert; Rheinlaender, Johannes; Schäffer, Tilman E; Bohn, Erwin; Frick, Julia-Stefanie; Borst, Oliver; Münzer, Patrick; Walker, Britta; Markel, Justin; Csanyi, Gabor; Pagano, Patrick J; Loughran, Patricia; Jessup, Morgan E; Watkins, Simon C; Bullock, Grant C; Sperry, Jason L; Zuckerbraun, Brian S; Billiar, Timothy R; Lotze, Michael T; Gawaz, Meinrad; Neal, Matthew D

    2015-12-01

    Thrombosis and inflammation are intricately linked in several major clinical disorders, including disseminated intravascular coagulation and acute ischemic events. The damage-associated molecular pattern molecule high-mobility group box 1 (HMGB1) is upregulated by activated platelets in multiple inflammatory diseases; however, the contribution of platelet-derived HMGB1 in thrombosis remains unexplored. Here, we generated transgenic mice with platelet-specific ablation of HMGB1 and determined that platelet-derived HMGB1 is a critical mediator of thrombosis. Mice lacking HMGB1 in platelets exhibited increased bleeding times as well as reduced thrombus formation, platelet aggregation, inflammation, and organ damage during experimental trauma/hemorrhagic shock. Platelets were the major source of HMGB1 within thrombi. In trauma patients, HMGB1 expression on the surface of circulating platelets was markedly upregulated. Moreover, evaluation of isolated platelets revealed that HMGB1 is critical for regulating platelet activation, granule secretion, adhesion, and spreading. These effects were mediated via TLR4- and MyD88-dependent recruitment of platelet guanylyl cyclase (GC) toward the plasma membrane, followed by MyD88/GC complex formation and activation of the cGMP-dependent protein kinase I (cGKI). Thus, we establish platelet-derived HMGB1 as an important mediator of thrombosis and identify a HMGB1-driven link between MyD88 and GC/cGKI in platelets. Additionally, these findings suggest a potential therapeutic target for patients sustaining trauma and other inflammatory disorders associated with abnormal coagulation.

  12. EVALUATION OF PLATELET COUNTS AND PLATELET INDICES AND THEIR SIGNIFICANT ROLE IN PRE-ECLAMPSIA AND ECLAMPSIA

    Directory of Open Access Journals (Sweden)

    Vijaya

    2014-03-01

    Full Text Available BACKGROUND: Preeclampsia and eclampsia are the most leading cause of maternal mortality in developing countries like ours. The aim of our study is to find out the relation between platelet indices and platelet counts with preeclampsia and eclampsia and their significance as prognostic indicator. MATERIALS AND METHOD: 82 cases of preeclampsia and 63 cases of eclampsia diagnosed between September 2010 to December 2013 were evaluated prospectively. One hundred healthy pregnant women with similar demographic features and gestational age without diagnosis of preeclampsia were included in the study of control group. Blood samples were analyzed by automated hematology analyzer. The platelet count, mean platelet volume and platelet distribution width were compared. RESULTS: The platelet counts were lower while mean platelet volume, platelet distribution width were increased in preeclampsia and eclampsia as compared to control group. CONCLUSION: We found an association between platelet indices and severity of preeclampsia. The estimation of platelet indices can be considered as an early, simple and rapid procedure in the assessment of severity of preeclampsia and eclampsia which can be used as a prognostic marker.

  13. Application of the extended nursing care in blood donors after the first apheresis platelet col ection%延续护理在首次单采血小板后献血者中的应用

    Institute of Scientific and Technical Information of China (English)

    龙雪芳; 卢丽霞; 黎添华; 梁静仪; 赖许肖

    2016-01-01

    Objective:To explore the application of the extended nursing care in blood donors after the first apheresis platelet collection. Methods:120 blood donors were randomly divided into the observation group and the control group(60 donors in each group),the routine nursing care was given to the donors in the control group and the extra extended nursing care was provided in the observation group,the change of thrombopoietin and platelet activating factor,life quality and satisfaction of the donors were compared between the two groups. Results:There were statistically significant differences in the comparison of the change of thrombopoietin and platelet activating factor be-tween the two groups before and after the intervention(P ﹤ 0. 05);the scores of life quality of the donors were superior in the observation group to the control group(P ﹤ 0. 01). Conclusion:The extended nursing care can relieve the psychological concerns of blood donors and improve their safety.%目的:探讨延续护理在首次单采血小板后献血者中的应用。探讨延续护理对首次单采血小板后献血者血小板生成素与血小板活化因子的影响。方法:将120名首次单采血小板献血者随机分为观察组和对照组各60名。对照组采用常规护理方式,观察组在此基础上采用延续护理模式,比较两组血小板生成素、血小板活化因子变化情况、干预后生活质量及服务满意度。结果:观察组干预前后血小板生成素及血小板活化因子变化比较差异有统计学意义( P ﹤0.05),观察组生活质量评分优于对照组(P ﹤0.01);观察组满意度较高。结论:通过延续护理可提高献血者献血安全,不会引起献血者的身体伤害,解除献血者心理顾虑,对招募起积极作用。

  14. Clopidogrel resistance of patients with coronary artery disease and its correlation with platelet count and mean platelet volume

    Institute of Scientific and Technical Information of China (English)

    李蕾

    2013-01-01

    Objective To explore the association between clopidogrel resistance(CR)as assessed by whole blood electrical impedance aggregometry(EIA) and platelet parameters.Methods The prospective study comprised 152 patients

  15. Platelet receptor expression and shedding: glycoprotein Ib-IX-V and glycoprotein VI.

    Science.gov (United States)

    Gardiner, Elizabeth E; Andrews, Robert K

    2014-04-01

    Quantity, quality, and lifespan are 3 important factors in the physiology, pathology, and transfusion of human blood platelets. The aim of this review is to discuss the proteolytic regulation of key platelet-specific receptors, glycoprotein(GP)Ib and GPVI, involved in the function of platelets in hemostasis and thrombosis, and nonimmune or immune thrombocytopenia. The scope of the review encompasses the basic science of platelet receptor shedding, practical aspects related to laboratory analysis of platelet receptor expression/shedding, and clinical implications of using the proteolytic fragments as platelet-specific biomarkers in vivo in terms of platelet function and clearance. These topics can be relevant to platelet transfusion regarding both changes in platelet receptor expression occurring ex vivo during platelet storage and/or clinical use of platelets for transfusion. In this regard, quantitative analysis of platelet receptor profiles on blood samples from individuals could ultimately enable stratification of bleeding risk, discrimination between causes of thrombocytopenia due to impaired production vs enhanced clearance, and monitoring of response to treatment prior to change in platelet count.

  16. Dengue virus binding and replication by platelets.

    Science.gov (United States)

    Simon, Ayo Y; Sutherland, Michael R; Pryzdial, Edward L G

    2015-07-16

    Dengue virus (DENV) infection causes ∼200 million cases of severe flulike illness annually, escalating to life-threatening hemorrhagic fever or shock syndrome in ∼500,000. Although thrombocytopenia is typical of both mild and severe diseases, the mechanism triggering platelet reduction is incompletely understood. As a probable initiating event, direct purified DENV-platelet binding was followed in the current study by quantitative reverse transcription-polymerase chain reaction and confirmed antigenically. Approximately 800 viruses specifically bound per platelet at 37°C. Fewer sites were observed at 25°C, the blood bank storage temperature (∼350 sites), or 4°C, known to attenuate virus cell entry (∼200 sites). Dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) and heparan sulfate proteoglycan were implicated as coreceptors because only the combination of anti-DC-SIGN and low-molecular-weight heparin prevented binding. Interestingly, at 37°C and 25°C, platelets replicated the positive sense single-stranded RNA genome of DENV by up to ∼4-fold over 7 days. Further time course experiments demonstrated production of viral NS1 protein, which is known to be highly antigenic in patient serum. The infectivity of DENV intrinsically decayed in vitro, which was moderated by platelet-mediated generation of viable progeny. This was shown using a transcription inhibitor and confirmed by freeze-denatured platelets being incapable of replicating the DENV genome. For the first time, these data demonstrate that platelets directly bind DENV saturably and produce infectious virus. Thus, expression of antigen encoded by DENV is a novel consideration in the pathogen-induced thrombocytopenia mechanism. These results furthermore draw attention to the possibility that platelets may produce permissive RNA viruses in addition to DENV.

  17. Metallomics studies of human blood serum from treated bipolar disorder patients.

    Science.gov (United States)

    Sussulini, Alessandra; Kratzin, Hartmut; Jahn, Olaf; Banzato, Claudio E Muller; Arruda, Marco A Zezzi; Becker, Johanna Sabine

    2010-07-01

    In the present work, metallomics studies using biomolecular (matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry, MALDI-TOF MS/MS) and elemental mass spectrometry (laser ablation inductively coupled plasma mass spectrometry, LA-ICPMS) of human blood serum samples from bipolar disorder (BD) patients compared to controls were performed. The serum samples from three different groups: control (n = 25), BD patients treated with Li (n = 15), and BD patients not treated with Li (n = 10), were pooled according to their groups and separated by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Then, in order to determine the metals bound to the protein spots and search for differences among the studied groups, the 2-D gels were analyzed by LA-ICPMS in three distinct modes: bioimaging of metals in gel sections, line scan through the protein spots, and microlocal analysis of selected protein spots. MALDI-TOF MS/MS characterized 32 serum proteins, and they were associated with the metals previously detected. When comparing control and treated BD patient groups, a differentiation in terms of metals bound to proteins was possible to observe. The main metals bound to proteins found in all groups were Na, Mg, Zn, Ca, and Fe. Mn was only detected in the control group; Co was only observed in the control and BD patients treated with Li group. K and Ti were only found in the BD patient groups, and P was only observed in control and BD patients not treated with Li drugs. This exploratory work shows that the association of LA-ICPMS with MALDI-TOF MS/MS is a powerful strategy in metallomics studies applied to determine differences in metal-containing proteins, being able to play an important role on the discovery of potential markers for BD and its treatment with Li in serum samples.

  18. Selective inhibition of the platelet phosphoinositide 3-kinase p110beta as promising new strategy for platelet protection during extracorporeal circulation.

    Science.gov (United States)

    Straub, Andreas; Wendel, Hans Peter; Dietz, Klaus; Schiebold, Daniela; Peter, Karlheinz; Schoenwaelder, Simone M; Ziemer, Gerhard

    2008-03-01

    Extracorporeal circulation (ECC) is used in cardiac surgery for cardiopulmonary bypass as well as in ventricular assist devices and for extracorporeal membrane oxygenation. Blood contact with the artificial surface and shear stress of ECC activates platelets and leukocytes resulting in a coagulopathy and proinflammatory events. Blockers of the platelet glycoprotein (GP) IIb/IIIa (CD41/CD61) can protect platelet function during ECC, a phenomenon called "platelet anaesthesia", but may be involved in post-ECC bleeding. We hypothesized that the new selective phosphoinositide 3-kinase p110beta inhibitor TGX-221 that inhibits shear-induced platelet activation without prolonging the bleeding time in vivo may also protect platelet function during ECC. Heparinized blood of healthy volunteers (n = 6) was treated in vitro with either the GP IIb/IIIa blocker tirofiban, TGX-221 or as control and circulated in an ECC model. Before and after 30 minutes circulation CD41 expression on the ECC-tubing as measure for platelet-ECC binding and generation of the platelet activation marker beta-thromboglobulin were determined using ELISA. Platelet aggregation and platelet-granulocyte binding were analysed in flow cytometry. After log-transforming the data statistical evaluation was performed using multifactor ANOVA in combination with Tukey's HSD test (global alpha = 5%). Tirofiban and TGX-221 inhibited platelet-ECC interaction, platelet aggregation and platelet-granulocyte binding. Tirofiban also inhibited ECC-induced beta-thromboglobulin release. The observed inhibition of platelet-ECC interaction and platelet activation by tirofiban contributes to explain the mechanism of "platelet anaesthesia". TGX-221 represents a promising alternative to GP IIb/IIIa blockade and should be further investigated for use during ECC in vivo.

  19. Challenges and promises for the development of donor-independent platelet transfusions.

    Science.gov (United States)

    Lambert, Michele P; Sullivan, Spencer K; Fuentes, Rudy; French, Deborah L; Poncz, Mortimer

    2013-04-25

    Platelet transfusions are often a life-saving intervention, and the use of platelet transfusions has been increasing. Donor-derived platelet availability can be challenging. Compounding this concern are additional limitations of donor-derived platelets, including variability in product unit quality and quantity, limited shelf life and the risks of product bacterial contamination, other transfusion-transmitted infections, and immunologic reactions. Because of these issues, there has been an effort to develop strategies to generate platelets from exogenously generated precursor cells. If successful, such platelets have the potential to be a safer, more consistent platelet product, while reducing the necessity for human donations. Moreover, ex vivo-generated autologous platelets or precursors may be beneficial for patients who are refractory to allogeneic platelets. For patients with inherited platelet disorders, ex vivo-generated platelets offer the promise of a treatment via the generation of autologous gene-corrected platelets. Theoretically, ex vivo-generated platelets also offer targeted delivery of ectopic proteins to sites of vascular injury. This review summarizes the current, state-of-the-art methodologies in delivering a clinically relevant ex vivo-derived platelet product, and it discusses significant challenges that must be overcome for this approach to become a clinical reality.

  20. 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...

  1. Correction of disorders in tissue perfusion, blood coagulation and fibrinolysis with Orbita apparatus on terahertz waves of cell metabolites

    Directory of Open Access Journals (Sweden)

    Vyacheslav F. Kirichuk

    2013-02-01

    Full Text Available This article contains information on principle of operation, technical parameters and possible application of Orbita {transliteration from Russian} apparatus for hemodynamic, fibrinolytic and peripheral perfusion disorders treatment. A single exposure to terahertz waves emitted by Orbita apparatus, corresponding to frequencies of molecular absorption and emission spectra of atmospheric oxygen (129.0 GHz, completely cures coagulant and fibrinolytic disorders of animals with acute immobilization stress. A course of treatment with electromagnetic waves corresponding to frequencies of molecular absorption and emission spectra of nitrogen oxide (150.176 – 150.664 leads to normalization of disrupted peripheral tissue perfusion parameters of animal undergoing treatment and stimulates basal and induced output of nitrogen oxide. This leads to decrease in peripheral vascular resistance to microcirculation and increase in blood flow to microvasculature. Experimental data provided in this article serves as a proof of viability of Orbita apparatus for treatment of coagulant, fibrinolytic and tissue perfusion disorders.

  2. Diagnostic usefulness of thrombus imaging scintigraphy for blood coagulopathy in the patients with aortic aneurysm. The comparison of /sup 111/In-oxine labelled platelet and sup(99m)Tc-fibrinogen scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Sakakibara, Yuzuru; Takeda, Toru; Ijima, Hiroshi; Nose, Tadao; Ishikawa, Nobuyoshi; Hori, Motokazu

    1984-07-01

    Eighteen patients with aortic aneurysm were studied to identify intraluminal thrombi using /sup 111/In-oxine labelled platelet and /sup 99m/Tc-fibrinogen scintigraphy. Reliability in the detection of thrombi with /sup 111/In-oxine labelled platelet scintigraphy was higher than that with /sup 99m/Tc-fibrinogen scintigraphy (94.1% vs 76.9%, respectively). Measurement of mean platelet survival time with /sup 111/In-oxine labelled autologous platelets were carried out in eight patients. Seven of them showed focal accumulation of the labelled platelets at the site of aortic aneurysm and mean platelet survival time (6.64 + 1.46 days) was shorter than normal. In the case of abdominal aneurysm, thrombocytopenia was present, his mean platelet survival time was 4.01 days and RI was accumulated at the site of aneurysm. His hematological pathophysiology could be explained as consumption coagulopathy in the abdominal aneurysm. Using scanning electron-microscopy, we found entrapped platelets with fine fibrin network were found indicating platelet consumption at the site of intraluminal thrombi. It was concluded that these imaging techniques using radioisotopes were very useful not only for detecting intraluminal thrombi but for diagnosing consumption coagulopathy and disseminated intravascular coagulation even where there is no clinical manifestation.

  3. Comparison of cytotoxic and anti-platelet activities of polyphenolic extracts from Arnica montana flowers and Juglans regia husks.

    Science.gov (United States)

    Rywaniak, Joanna; Luzak, Boguslawa; Podsedek, Anna; Dudzinska, Dominika; Rozalski, Marcin; Watala, Cezary

    2015-01-01

    Polyphenolic compounds of plant origin are well known to be beneficial to human health: they exert protective effects on haemostasis and have a particular influence on blood platelets. However, the anti-platelet properties of polyphenolic compounds observed so far have not been weighed against their potential cytotoxic action against platelets. The aim of this study was to demonstrate that anti-platelet and cytotoxic effects on blood platelets may interfere and therefore, may often lead to confusion when evaluating the properties of plant extracts or other agents towards blood platelets. The anti-platelet and cytotoxic in vitro effects of plant extracts obtained from the husks of walnuts (J. regia) and flowers of arnica (A. montana) on platelet reactivity and viability were examined. Platelet function was assessed using standard methods (flow cytometry: P-selectin expression, activation of GPIIbIIIa complex, vasodilator-stimulated phosphoprotein, VASP index; turbidimetric and impedance aggregometry) and newly set assays (flow cytometric monitoring of platelet cytotoxicity). The results reveal that none of the studied plant extracts demonstrated cytotoxicity towards blood platelets. The phenolic acid-rich extract of A. montana (7.5 and 15 µg/ml) significantly reduced the ADP-induced aggregation in both whole blood and PRP, and decreased the platelet reactivity index (PRI; VASP phosphorylation) in whole blood, while showing excellent antioxidant capacity. The extract of J. regia husks significantly reduced ADP-induced platelet aggregation in whole blood when applied at 7.5 µg/ml, and only slightly decreased the PRI at 15 µg/ml. Both examined extracts suppressed platelet hyper-reactivity, and such influence did not interfere with cytotoxic effects of the extracts. Thus, its high polyphenol content, excellent antioxidant capacity and distinct anti-platelet properties, in combination with its lack of toxicity, make the extract of A. montana flowers a possible

  4. 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

  5. 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

  6. 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.

  7. 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

  8. Are Platelets Cells? And if Yes, are They Immune Cells?

    Science.gov (United States)

    Garraud, Olivier; Cognasse, Fabrice

    2015-01-01

    Small fragments circulating in the blood were formally identified by the end of the nineteenth century, and it was suggested that they assisted coagulation via interactions with vessel endothelia. Wright, at the beginning of the twentieth 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 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 immune

  9. 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 ...

  10. Effects of Suilysin on Streptococcus suis-Induced Platelet Aggregation

    Science.gov (United States)

    Zhang, Shengwei; Wang, Junping; Chen, Shaolong; Yin, Jiye; Pan, Zhiyuan; Liu, Keke; Li, Lin; Zheng, Yuling; Yuan, Yuan; Jiang, Yongqiang

    2016-01-01

    Blood platelets play important roles during pathological thrombocytopenia in streptococcal toxic shock syndrome (STSS). Streptococcus suis (S. suis) an emerging human pathogen, can cause STSS similarly to S. pyogenes. However, S. suis interactions with platelets are poorly understood. Here, we found that suilysin (SLY), different from other bacterial cholesterol-dependent cytolysins (CDCs), was the sole stimulus that induced platelet aggregation. Furthermore, the inside-out activation of GPIIb/IIIa of platelets mediated SLY-induced platelet aggregation. This process was triggered by Ca2+ influx that depend on the pore forming on platelets by SLY. Additionally, although SLY induced α-granule release occurred via the MLCK-dependent pathway, PLC-β-IP3/DAG-MLCK and Rho-ROCK-MLCK signaling were not involved in SLY-induced platelet aggregation. Interestingly, the pore dependent Ca2+ influx was also found to participate in the induction of platelet aggregation with pneumolysin (PLY) and streptolysin O (SLO), two other CDCs. It is possible that the CDC-mediated platelet aggregation we observed in S. suis is a similar response mechanism to that used by a wide range of bacteria. These findings might lead to the discovery of potential therapeutic targets for S. suis-associated STSS. PMID:27800304

  11. 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...

  12. 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...

  13. 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.

  14. 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

  15. 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...

  16. 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…

  17. 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

  18. 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

  19. 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 ...

  20. 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

  1. Mice lacking the SLAM family member CD84 display unaltered platelet function in hemostasis and thrombosis.

    Directory of Open Access Journals (Sweden)

    Sebastian Hofmann

    Full Text Available BACKGROUND: Platelets are anuclear cell fragments derived from bone marrow megakaryocytes that safeguard vascular integrity by forming thrombi at sites of vascular injury. Although the early events of thrombus formation--platelet adhesion and aggregation--have been intensively studied, less is known about the mechanisms and receptors that stabilize platelet-platelet interactions once a thrombus has formed. One receptor that has been implicated in this process is the signaling lymphocyte activation molecule (SLAM family member CD84, which can undergo homophilic interactions and becomes phosphorylated upon platelet aggregation. OBJECTIVE: The role of CD84 in platelet physiology and thrombus formation was investigated in CD84-deficient mice. METHODS AND RESULTS: We generated CD84-deficient mice and analyzed their platelets in vitro and in vivo. Cd84(-/- platelets exhibited normal activation and aggregation responses to classical platelet agonists. Furthermore, CD84 deficiency did not affect integrin-mediated clot retraction and spreading of activated platelets on fibrinogen. Notably, also the formation of stable three-dimensional thrombi on collagen-coated surfaces under flow ex vivo was unaltered in the blood of Cd84(-/- mice. In vivo, Cd84(-/- mice exhibited unaltered hemostatic function and arterial thrombus formation. CONCLUSION: These results show that CD84 is dispensable for thrombus formation and stabilization, indicating that its deficiency may be functionally compensated by other receptors or that it may be important for platelet functions different from platelet-platelet interactions.

  2. "A Fire in the Blood": metaphors of bipolar disorder in Jamison's An Unquiet Mind.

    Science.gov (United States)

    Schoeneman, Thomas J; Putnam, Janel; Rasmussen, Ian; Sparr, Nina; Beechem, Stephanie

    2012-09-01

    Content analysis of three chapters of Jamison's memoir, An Unquiet Mind, shows that depression, mania, and Bipolar Disorder have a common metaphoric core as a sequential process of suffering and adversity that is a form of malevolence and destruction. Depression was down and in, while mania was up, in and distant, circular and zigzag, a powerful force of quickness and motion, fieriness, strangeness, seduction, expansive extravagance, and acuity. Bipolar Disorder is down and away and a sequential and cyclical process that partakes of the metaphors of its component moods. We conclude that metaphors of mood disorders share a number of structural features and are consistent across different authors. PMID:22588681

  3. "A Fire in the Blood": metaphors of bipolar disorder in Jamison's An Unquiet Mind.

    Science.gov (United States)

    Schoeneman, Thomas J; Putnam, Janel; Rasmussen, Ian; Sparr, Nina; Beechem, Stephanie

    2012-09-01

    Content analysis of three chapters of Jamison's memoir, An Unquiet Mind, shows that depression, mania, and Bipolar Disorder have a common metaphoric core as a sequential process of suffering and adversity that is a form of malevolence and destruction. Depression was down and in, while mania was up, in and distant, circular and zigzag, a powerful force of quickness and motion, fieriness, strangeness, seduction, expansive extravagance, and acuity. Bipolar Disorder is down and away and a sequential and cyclical process that partakes of the metaphors of its component moods. We conclude that metaphors of mood disorders share a number of structural features and are consistent across different authors.

  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. 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

  6. Transfused stored platelets have the same haemostatic function as circulating native platelets

    NARCIS (Netherlands)

    Roeloffzen, W. W. H.; Kluin-Nelemans, H. C.; Veeger, N. J. G. M.; de Wolf, J. Th. M.

    2010-01-01

    Background and objectives As thrombelastography (R) (TEG) measures haemostasis in whole blood, we used this instrument to study whether transfused platelets (PLTs) have the same haemostatic function compared to native circulating PLTs. Further, we studied the effect of storage time on the haemostati

  7. Pressure-aided transfusion of platelets: does it affect the platelets?

    DEFF Research Database (Denmark)

    Fischer-Nielsen, Anne; Stissing, Trine; Maansson, Charlotte;

    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. [Dynamics of violations of intravascular platelet activity in rats during the formation of metabolic syndrome using fructose models].

    Science.gov (United States)

    Medvedev, I N

    2016-01-01

    Objective: To trace the development of disorders intravascular platelet activity in experimental form of the metabolic syndrome. The study included 61 rat male Wistar rats at the age of 2.5-3 months. Animals were divided into 2 groups: 32 rats were given free access to drink 10% solution of fructose for 8 weeks and 29 rats were the control group. The level of the total cholesterol, high density lipoprotein cholesterol (HDLD cholesterol) and triglycerides were determined using colorimetric enzymatic method. The blood plasma content of endothelin-1 was determined by radioimmunoassay, thromboxane B2 and 6-keto-prostaglandin F(1α)--by ELISA. The total content of nitrogen oxide metabolites was revealed in blood. Intravascular platelet activity was assessed using phase contrast microscopy. In terms of fructose load in rats simultaneously with the increase of body weight and the development of biochemical disorders that are characteristic for the metabolic syndrome, there comes a marked progressive increase in intravascular platelet activity [reduction of the number of discocytes from 81.0 ± 0.1 to 61.3 ± 0.2%, increase in the number of reactive platelets from 19.0 ± 0.1 to 38.7 ± 0.2%, an increase in the number of freely moving in the blood of small units from 2.4 ± 0.0 to 14.6 ± 0.1 per 100 free platelets, and of medium and large units (from 4 or more cells) from 0.1 ± 0.03 to 2.3 ± 0.06 per 100 free platelets], largely due to the increase (p < 0.01) of the synthesis of thromboxane B2 (from 145.9 ± 0.2 to 232.6 ± 0.7 pg/ml), endothelin-4 (from 6.9 ± 0.2 to 12.5 ± 0.4 pg/ml) and reduction (p < 0.01) of the generation of 6-keto-prostaglandin F1α (from 75.9 ± 0.2 to 62.3 ± 0.4 pg/ml), and the total amount of nitric oxide metabolites (from 27.9 ± 0.3 to 23.2 ± 0.1 mmol/l). PMID:27228700

  9. Point-of-care platelet function tests: detection of platelet inhibition induced by nonopioid analgesic drugs.

    Science.gov (United States)

    Scharbert, Gisela; Gebhardt, Kristina; Sow, Zacharia; Duris, Monika; Deusch, Engelbert; Kozek-Langenecker, Sibylle

    2007-12-01

    Detection of platelet inhibition is of clinical relevance in the preinterventional risk-benefit assessment in chronic low-back-pain patients scheduled for invasive pain therapy. We evaluated the sensitivity of various point-of-care platelet function tests for the detection of platelet inhibition induced by nonopioid analgesic drugs. After Institutional Review Board approval and informed consent, citrated whole blood from 40 patients with chronic unspecific low back pain was investigated before and 30 min after intravenous infusion of the study medication consisting of diclofenac 75 mg (plus orphenadrin 30 mg; Neodolpasse; Fresenius Kabi Austria GmbH, Austria), parecoxib 40 mg (Dynastat; Pharmacia Europe EEIG, UK), paracetamol 1 g (Perfalgan; Bieffe Medital S.P.A., Italy), or normal saline in a randomized, cross-over, double-blinded, placebo-controlled study. Platelet function was assessed using the PFA-100 platelet function analyzer and thromboelastometry, as well as impedance aggregometry (in the last 17 patients recruited after it became commercially available). Sensitivity for detecting diclofenac-induced platelet inhibition was 85% for the PFA-100 using epinephrine as agonist and 94% for arachidonic acid-induced impedance aggregometry. ADP-induced platelet function tests, as well as cytochalasin D-modified thromboelastometry were unreliable. All tests had a low incidence of false-positive test results after normal saline. Paracetamol and parecoxib had no significant platelet inhibiting effect. The PFA-100 using epinephrine as agonist and arachidonic acid-induced impedance aggregometry are recommended for the detection of cyclooxygenase-I-inhibiting effects of nonsteroidal anti-inflammatory drugs such as diclofenac. Our findings confirm that a single rescue dose of paracetamol and parecoxib has no antiplatelet effect. PMID:17982319

  10. Ameliorative effects of vanillin on potassium bromate induces bone and blood disorders in vivo.

    Science.gov (United States)

    Ben Saad, H; Ben Amara, I; Krayem, N; Boudawara, T; Kallel, C; Zeghal, K M; Hakim, A

    2015-11-08

    The objective of this study was to investigate the propensity of potassium bromate (KBrO3) to induce oxidative stress in blood and bone of adult mice and its possible attenuation by vanillin. Our results demonstrated, after KBrO3 treatment, a decrease of red blood cells and hemoglobin and a significant increase of white blood cell. A decrease in plasma levels of folic acid, vitamin B12 and iron was also noted. Interestingly, an increase of lipid peroxidation, hydroperoxides, hydrogen peroxide, advanced oxidation protein products and protein carbonyl levels in erythrocytes and bone was observed, while superoxide dismutase, catalase and glutathione peroxidase activities and glutathione, non-protein thiol and vitamin C levels were decreased. KBrO3 treatment resulted in blood and bone DNA fragmentation, a hallmark of genotoxicity-KBrO3-induced, with reduction of DNA levels. Calcium and phosphorus levels showed a decrease in the bone and an increase in the plasma after KBrO3 treatment. These biochemical alterations were accompanied by histological changes in the blood smear and bone tissue. Treatment with vanillin improved the histopathological, hematotoxic and genotoxic effects induced by KBrO3. The results showed, for the first time, that the vanillin possesses a potent protective effect against the oxidative stress and genotoxicity in bone and blood of KBrO3-treated mice.

  11. 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

  12. 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

  13. The repertoire and features of human platelet microRNAs.

    Directory of Open Access Journals (Sweden)

    Hélène Plé

    Full Text Available Playing a central role in the maintenance of hemostasis as well as in thrombotic disorders, platelets contain a relatively diverse messenger RNA (mRNA transcriptome as well as functional mRNA-regulatory microRNAs, suggesting that platelet mRNAs may be regulated by microRNAs. Here, we elucidated the complete repertoire and features of human platelet microRNAs by high-throughput sequencing. More than 492 different mature microRNAs were detected in human platelets, whereas the list of known human microRNAs was expanded further by the discovery of 40 novel microRNA sequences. As in nucleated cells, platelet microRNAs bear signs of post-transcriptional modifications, mainly terminal adenylation and uridylation. In vitro enzymatic assays demonstrated the ability of human platelets to uridylate microRNAs, which correlated with the presence of the uridyltransferase enzyme TUT4. We also detected numerous microRNA isoforms (isomiRs resulting from imprecise Drosha and/or Dicer processing, in some cases more frequently than the reference microRNA sequence, including 5' shifted isomiRs with redirected mRNA targeting abilities. This study unveils the existence of a relatively diverse and complex microRNA repertoire in human platelets, and represents a mandatory step towards elucidating the intraplatelet and extraplatelet role, function and importance of platelet microRNAs.

  14. Flow Cytometric Investigation of Classical and Alternative Platelet Activation Markers

    Science.gov (United States)

    Debreceni, Ildikó Beke; Kappelmayer, János

    2013-01-01

    Platelets show a substantial role in the maintenance of vascular integrity when these cells after a rapid activation adhere to the vessel wall lesion, aggregate with other platelets and leukocytes resulting in an arterial thrombosis. Analysis of in vivo platelet activation at an early time point is crucial in the detection of developing thrombotic events. In addition, the forecast of future complications as well as the evaluation of the efficacy of anti- platelet medication are also essential in a large group of patients. Changes in the levels of platelet receptors or alteration in other surface properties due to intra- and extracellular responses to a stimulus can be measurable primarily by flow cytometry with specific antibodies via the assessment of classical and alternative platelet activation markers. Some of these biomarkers have been already used in routine laboratory settings in many cases, while others still stand in the phase of research applications. Deficiency in platelet receptors is also accessible with this technique for the diagnosis of certain bleeding disorders. We here describe the most important types of platelet activation markers, and give an overview how the levels of these markers are altered in different diseases.

  15. Nanotechnology: Platelet mimicry

    Science.gov (United States)

    Farokhzad, Omid C.

    2015-10-01

    Cloaking drug-loaded nanoparticles with platelet membranes enhances the drugs' abilities to target desired cells and tissues. This technology might improve treatments for cardiovascular and infectious diseases. See Letter p.118

  16. 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

  17. 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.

  18. 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

  19. Platelet Aggregation Inhibitors from Aerial Parts of Ruta Chalepensis Grown in Jordan

    Directory of Open Access Journals (Sweden)

    Mayadah B. Shehadeh

    2007-01-01

    Full Text Available From the aerial parts of Ruta chalepensis L., grown in Jordan, two furanocoumarins (bergapten and chalepensin, one flavonoid glycoside (rutin as well as several minor compounds have been isolated. The structural elucidation of these compounds was established based on spectral data (UV, IR, MS,1H-NMR and 13C-NMR. In Jordan, R. chalepensis is recommended for the treatment of rheumatism, mental disorders and menstrual problems. Fresh and dried leaves are used as flavoring agent in food and beverages. Antiplatelet activities of the crude methanolic and ethylacetate extracts in addition to the three isolated major compounds were measured by the aggrometric method according to Beretz and Casenave. Optical aggregometer connected to dual channel recorder was used for measuring aggregation. Both, ethylacetate and methanol extracts inhibited ADP- induced platelet aggregation (ADP-IA of human blood. However, only ethylacetate extract was able to induce 50% inhibition of collagen-induced platelet aggregation (Co-IA platelet rich plasma. Bergapten was more active against ADP-IA compared to chalepensin while the latter was more active against Co-IA compared to bergapten.

  20. The effect of epoprostenol on platelet activation and consumption during experimental extracorporeal perfusion

    DEFF Research Database (Denmark)

    Skogby, M; Adrian, K; Friberg, L;

    1999-01-01

    on the ECLS induced platelet consumption and activation. In terms of the methods, identical in vitro ECLS circuits were primed with fresh heparinized human blood and circulated for 24 h. Epoprostenol (2.4 microg/L blood/h) was added to one of the circuits in each pair. In total, 6 paired experiments were...... performed. The platelet count, neutrophil count, plasma concentration of hemoglobin, and platelet membrane expression of glycoproteins (GP) Ib and IIb/IIIa were assayed before the start and at 0.5, 1, 3, 12 and 24 h of perfusion. Higher platelet counts were observed in the experimental circuits. However...

  1. Human platelet glycoprotein Ia. One component is only expressed on the surface of activated platelets and may be a granule constituent

    Energy Technology Data Exchange (ETDEWEB)

    Bienz, D.; Clemetson, K.J.

    1989-01-05

    Glycoprotein Ia (GP Ia) is a relatively minor component of human blood platelets thought to be a receptor involved in collagen-induced platelet activation. However, some difficulties exist with the definition of this glycoprotein. The expression of GP Ia on resting (prostacyclin analogue-treated) and thrombin-activated platelets was compared by surface labeling with /sup 125/I-lactoperoxidase. Intact platelets or platelets solubilized in sodium dodecyl sulfate were labeled with periodate/(/sup 3/H)NaBH/sub 4/. Analysis on two-dimensional isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels showed that GP Ia is very poorly labeled in resting platelets. After activation a new spot (GP Ia*) appears with the same relative molecular mass as GP Ia under reducing conditions. GP Ia and Ia* can be clearly separated by two-dimensional nonreduced/reduced gel electrophoresis. Therefore, two glycoproteins which have been termed GP Ia exist in platelets with similar molecular weight and pI under reducing conditions. One of these (GP Ia*) is only surface-labeled when platelets are activated, indicating that it is only exposed on the surface of activated platelets. Supernatant from activated platelets contains this glycoprotein as well as other granule components. This glycoprotein is missing in platelets from two patients with collagen-response defects.

  2. 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

  3. Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part III: leucocyte activation: a new feature for platelet concentrates?

    Science.gov (United States)

    Dohan, David M; Choukroun, Joseph; Diss, Antoine; Dohan, Steve L; Dohan, Anthony J J; Mouhyi, Jaafar; Gogly, Bruno

    2006-03-01

    Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. In this third article, we investigate the immune features of this biomaterial. During PRF processing, leucocytes could also secrete cytokines in reaction to the hemostatic and inflammatory phenomena artificially induced in the centrifuged tube. We therefore undertook to quantify 5 significant cell mediators within platelet poor plasma supernatant and PRF clot exudate serum: 3 proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha), an antiinflammatory cytokine (IL-4), and a key growth promoter of angiogenesis (VEGF). Our data are correlated with that obtained in plasma (nonactivated blood) and in sera (activated blood). These initial analyses revealed that PRF could be an immune regulation node with inflammation retrocontrol abilities. This concept could explain the reduction of postoperative infections when PRF is used as surgical additive.

  4. 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...

  5. 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.

  6. Platelet preservation: agitation and containers.

    Science.gov (United States)

    van der Meer, Pieter F; de Korte, Dirk

    2011-06-01

    For platelets to maintain their in vitro quality and in vivo effectiveness, they need to be stored at room temperature with gentle agitation in gas-permeable containers. The mode of agitation affects the quality of the platelets, and a gentle method of agitation, either a circular or a flat bed movement, provides the best results. Tumblers or elliptical agitators induce platelet activation and subsequent damage. As long as the platelets remain in suspension, the agitation speed is not important. Agitation of the platelet concentrates ensures that the platelets are continuously oxygenated, that sufficient oxygen can enter the storage container and that excess carbon dioxide can be expelled. During transportation of platelet concentrates, nowadays over long distances where they are held without controlled agitation, platelets may tolerate a certain period without agitation. However, evidence is accumulating that during the time without agitation, local hypoxia surrounding the platelets may induce irreversible harm to the platelets. Over the decades, more gas-permeable plastics have been used to manufacture platelet containers. The use of different plastics and their influence on the platelet quality both in vitro and in vivo is discussed. The improved gas-permeability has allowed the extension of platelet storage from 3 days in the early 1980s, to currently at least 7 days. In the light of new developments, particularly the introduction of pathogen reduction techniques, the use of platelet additive solutions and the availability of improved automated separators, further (renewed) research in this area is warranted.

  7. Platelets Roll on Stimulated Endothelium in vivo: An Interaction Mediated by Endothelial P-Selectin

    Science.gov (United States)

    Frenette, Paul S.; Johnson, Robert C.; Hynes, Richard O.; Wagner, Denisa D.

    1995-08-01

    P-selectin, found in storage granules of platelets and endothelial cells, can be rapidly expressed upon stimulation. Mice lacking this membrane receptor exhibit a severe impairment of leukocyte rolling. We observed that, in addition to leukocytes, platelets were rolling in mesenteric venules of wild-type mice. To investigate the role of P-selectin in this process, resting or activated platelets from wild-type or P-selectin-deficient mice were fluorescently labeled and transfused into recipients of either genotype. Platelet-endothelial interactions were monitored by intravital microscopy. We observed rolling of either wild-type or P-selectin-deficient resting platelets on wild-type endothelium. Endothelial stimulation with the calcium ionophore A23187 increased the number of platelets rolling 4-fold. Activated P-selectin-deficient platelets behaved similarly, whereas activated wild-type platelets bound to leukocytes and were seen rolling together. Platelets of either genotype, resting or activated, interacted minimally with mutant endothelium even after A23187 treatment. The velocity of platelet rolling was 6- to 9-fold greater than that of leukocytes. Our results demonstrate that (i) platelets roll on endothelium in vivo, (ii) this interaction requires endothelial but not platelet P-selectin, and (iii) platelet rolling appears to be independent of platelet activation, indicating constitutive expression of a P-selectin ligand(s) on platelets. We have therefore observed an interesting parallel between platelets and leukocytes in that both of these blood cell types roll on stimulated vessel wall and that this process is dependent on the expression of endothelial P-selectin.

  8. The association of annual air pollution exposure with blood pressure among patients with sleep-disordered breathing.

    Science.gov (United States)

    Liu, Wen-Te; Lee, Kang-Yun; Lee, Hsin-Chien; Chuang, Hsiao-Chi; Wu, Dean; Juang, Jer-Nan; Chuang, Kai-Jen

    2016-02-01

    While sleep-disordered breathing (SDB), high blood pressure (BP) and air pollution exposure have separately been associated with increased risk of cardiopulmonary mortality, the association linking air pollution exposure to BP among patients with sleep-disordered breathing is still unclear. We collected 3762 participants' data from the Taipei Medical University Hospital's Sleep Center and air pollution data from the Taiwan Environmental Protection Administration. Associations of 1-year mean criteria air pollutants [particulate matter with aerodynamic diameters ≤10 μm (PM10), particulate matter with aerodynamic diameters ≤2.5 μm (PM2.5), nitrogen dioxide (NO2) and ozone (O3)] with systolic BP (SBP) and diastolic BP (DBP) were investigated by generalized additive models. After controlling for age, sex, body mass index (BMI), temperature and relative humidity, we observed that increases in air pollution levels were associated with decreased SBP and increased DBP. We also found that patients with apnea-hypopnea index (AHI) ≥30 showed a stronger BP response to increased levels of air pollution exposure than those with AHIpollution exposure on BP were found in overweight participants than in participants with normal BMI. We concluded that annual exposure to air pollution was associated with change of BP among patients with sleep-disordered breathing. The association between annual air pollution exposure and BP could be modified by AHI and BMI.

  9. 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.

  10. Sticky platelet syndrome: history and future perspectives.

    Science.gov (United States)

    Kubisz, Peter; Ruiz-Argüelles, Guillermo J; Stasko, Jan; Holly, Pavol; Ruiz-Delgado, Guillermo J

    2014-07-01

    The sticky platelet syndrome (SPS) is a thrombophilic qualitative platelet disorder with familial occurrence and autosomal dominant trait, characterized by increased in vitro platelet aggregation after low concentrations of adenosine diphosphate and/or epinephrine. Its clinical manifestation includes arterial thrombosis, pregnancy complications (fetal growth retardation and fetal loss), and less often venous thromboembolism. SPS was considered to be a rare thrombophilic disorder, but it can be found relatively often as a cause of unexplained thrombosis, particularly among patients with arterial thrombosis such as stroke. The syndrome was recognized as a distinct disorder in 1983 by Holiday and further characterized in the 1980s and 1990s, with Mammen and Bick providing the key findings. Although recognized for more than 30 years, significant issues, namely the syndrome's etiology, inheritance, and epidemiology, remain unclear. The aim of the first part of this review is to summarize the previous 35 years of the research into, and to provide a brief historical account of, SPS. The history section is focused particularly on the work of two most prominent investigators: Eberhard F. Mammen and Rodger L. Bick. The second part summarizes the present understanding of the syndrome and outlines unresolved issues and the trends in which the future research is likely to continue. PMID:24911675

  11. Platelets and cardiac arrhythmia

    Directory of Open Access Journals (Sweden)

    Jonas S De 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. 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.

  13. 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

  14. Platelets are versatile cells: New discoveries in hemostasis, thrombosis, immune responses, tumor metastasis and beyond.

    Science.gov (United States)

    Xu, Xiaohong Ruby; Zhang, Dan; Oswald, Brigitta Elaine; Carrim, Naadiya; Wang, Xiaozhong; Hou, Yan; Zhang, Qing; Lavalle, Christopher; McKeown, Thomas; Marshall, Alexandra H; Ni, Heyu

    2016-12-01

    Platelets are small anucleate blood cells generated from megakaryocytes in the bone marrow and cleared in the reticuloendothelial system. At the site of vascular injury, platelet adhesion, activation and aggregation constitute the first wave of hemostasis. Blood coagulation, which is initiated by the intrinsic or extrinsic coagulation cascades, is the second wave of hemostasis. Activated platelets can also provide negatively-charged surfaces that harbor coagulation factors and markedly potentiate cell-based thrombin generation. Recently, deposition of plasma fibronectin, and likely other plasma proteins, onto the injured vessel wall has been identified as a new "protein wave of hemostasis" that may occur even earlier than the first wave of hemostasis, platelet accumulation. Although no experimental evidence currently exists, it is conceivable that platelets may also contribute to this protein wave of hemostasis by releasing their granule fibronectin and other proteins that may facilitate fibronectin self- and non-self-assembly on the vessel wall. Thus, platelets may contribute to all three waves of hemostasis and are central players in this critical physiological process to prevent bleeding. Low platelet counts in blood caused by enhanced platelet clearance and/or impaired platelet production are usually associated with hemorrhage. Auto- and allo-immune thrombocytopenias such as idiopathic thrombocytopenic purpura and fetal and neonatal alloimmune thrombocytopenia may cause life-threatening bleeding such as intracranial hemorrhage. When triggered under pathological conditions such as rupture of an atherosclerotic plaque, excessive platelet activation and aggregation may result in thrombosis and vessel occlusion. This may lead to myocardial infarction or ischemic stroke, the major causes of mortality and morbidity worldwide. Platelets are also involved in deep vein thrombosis and thromboembolism, another leading cause of mortality. Although fibrinogen has been

  15. Inhibiting platelets aggregation could aggravate the acute infection caused by Staphylococcus aureus.

    Science.gov (United States)

    Zhang, Xin; Liu, Yu; Gao, Yaping; Dong, Jie; Mu, Chunhua; Lu, Qiang; Shao, Ningsheng; Yang, Guang

    2011-01-01

    Several fibrinogen binding proteins (Fibs) play important roles in the pathogenesis of Staphylococcus aureus (S. aureus). Most Fibs can promote the aggregation of platelets during infection, but the extracellular fibrinogen-binding protein (Efb) is an exception. It is reported that Efb can specifically bind fibrinogen and inhibit the aggregation of platelet with its N terminal. However, the biological significance of platelet aggregation inhibition in the infection caused by S. aureus is unclear until now. Here, we demonstrated that the persistence and aggregation of platelets were important for killing S. aureus in whole blood. It was found that the N terminal of Efb (EfbN) and platelets inhibitors could increase the survival of S. aureus in whole blood. The study in vivo also showed that EfbN and platelets inhibitors could reduce the killing of S. aureus and increase the lethality rate of S. aureus in the acute infection mouse model.

  16. 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;

    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......, recovery of rat platelet function after ticagrelor differs mechanistically from that after clopidogrel. This difference is masked by conventional platelet aggregation methods, but is revealed by thrombus formation measurement under flow. Juvenile platelets formed at later time points after clopidogrel...... 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...

  17. 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.

  18. 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.

  19. Reduced platelet-mediated and enhanced leukocyte-mediated fibrinolysis in experimentally induced diabetes in rats

    Energy Technology Data Exchange (ETDEWEB)

    Winocour, P.D.; Colwell, J.A.

    1985-05-01

    Studies of fibrinolytic activity in diabetes mellitus have produced conflicting results. This may be a result of methodologic insensitivity or of variable contributions of the different blood components to whole blood fibrinolysis. To explore these two possibilities, the authors used a sensitive solid-phase radiometric assay to examine the fibrinolytic activity of whole blood, platelet-rich plasma, leukocytes, and platelet- and leukocyte-poor plasma prepared from control rats and rats with streptozocin-induced diabetes at various times after induction of diabetes. Fibrinolytic activity of whole blood from diabetic rats after 7 days was significantly reduced, and remained reduced after longer durations of diabetes up to 28 days. Platelet-rich plasma from diabetic rats had decreased fibrinolytic activity, which followed the same time course of changes as in whole blood. The platelet contribution to whole blood fibrinolysis was further reduced in vivo after 14 days of diabetes by a reduced whole blood platelet count. In contrast, fibrinolytic activity of leukocytes from diabetic rats became enhanced after 7 days of diabetes. After 49 days of diabetes, the whole blood leukocyte count was reduced, and in vivo would offset the enhanced activity. Plasma fibrinolytic activity was small compared with that of whole blood and was unaltered in diabetic rats. The authors conclude that altered platelet function contributes to decreased fibrinolytic activity of whole blood in diabetic rats, and that this may be partially offset by enhanced leukocyte-mediated fibrinolysis.

  20. HMGB1 binds to activated platelets via the receptor for advanced glycation end products and is present in platelet rich human coronary artery thrombi.

    Science.gov (United States)

    Ahrens, Ingo; Chen, Yung-Chih; Topcic, Danijal; Bode, Michael; Haenel, David; Hagemeyer, Christoph E; Seeba, Hannah; Duerschmied, Daniel; Bassler, Nicole; Jandeleit-Dahm, Karin A; Sweet, Matthew J; Agrotis, Alex; Bobik, Alex; Peter, Karlheinz

    2015-11-01

    High mobility group box 1 (HMGB1) acts as both a nuclear protein that regulates gene expression, as well as a pro-inflammatory alarmin that is released from necrotic or activated cells. Recently, HMGB1-expression in human atherosclerotic plaques was identified. Therapeutic blockade of HMGB1 reduced the development of diet-induced atherosclerosis in ApoE knockout mice. Thus, we hypothesised an interaction between HMGB1 and activated platelets. Binding of recombinant HMGB1 to platelets was assessed by flow cytometry. HMGB1 bound to thrombin-activated human platelets (MFI 2.49 vs 25.01, p=0.0079). Blood from wild-type, TLR4 and RAGE knockout mice was used to determine potential HMGB1 receptors on platelets. HMGB1 bound to platelets from wild type C57Bl6 (MFI 2.64 vs 20.3, p 0.05). RAGE expression on human platelets was detected by RT-PCR with mRNA extracted from highly purified platelets and confirmed by Western blot and immunofluorescence microscopy. Platelet activation increased RAGE surface expression (MFI 4.85 vs 6.74, p< 0.05). Expression of HMGB1 in human coronary artery thrombi was demonstrated by immunohistochemistry and revealed high expression levels. Platelets bind HMGB1 upon thrombin-induced activation. Platelet specific expression of RAGE could be detected at the mRNA and protein level and is involved in the binding of HMGB1. Furthermore, platelet activation up-regulates platelet surface expression of RAGE. HMGB1 is highly expressed in platelet-rich human coronary artery thrombi pointing towards a central role for HMGB1 in atherothrombosis, thereby suggesting the possibility of platelet targeted anti-inflammatory therapies for atherothrombosis.

  1. Role of platelet function and platelet membrane glycoproteins in children with primary immune thrombocytopenia.

    Science.gov (United States)

    Liu, Wen-Jun; Bai, Jing; Guo, Qu-Lian; Huang, Zhe; Yang, Hong; Bai, Yong-Qi

    2016-09-01

    The aim of the present study was to examine and understand changes in platelet functions prior to and after the treatment of primary immune thrombocytopenia (ITP) in children. An automatic hematology analyzer and whole blood flow cytometry were used to detect immature platelet fraction (IPF), IPC and membrane glycoproteins (CD62p, PAC-1 and CD42b) in ITP children (ITP group), children with complete response after ITP treatment (ITP-CR group) and children with elective surgery (normal control group). The results showed that, levels of platelet count (PLT) and plateletcrit in the ITP group were lower alhtough the levels of mean platelet volume, platelet distribution width and platelet-large cell ratio (P-LCR) were higher than those in the normal control and ITP-CR groups. PLT in the ITP-CR group was lower than that in the normal controls. Additionally, IPF% was higher in the normal control and ITP-CR groups, IPC was lower in the ITP group compared to the normal control and ITP-CR groups. Furthermore, prior to ADP activation, the expression levels of CD62p, PAC-1 and CD42b in the ITP group were lower in ITP group than those in the normal control and ITP-CR groups. The expression level of PAC-1 was lower in the ITP-CR and normal control groups. No differences were identified in CD62p and CD42b expression levels. Following ATP activation, CD62p, PAC-1 and CD42b expression in the ITP group was lower than that in the normal control and ITP-CR groups. PAC-1 expression was lower while CD62p expression was higher in the ITP-CR group compared to the normal control group. In conclusion, the activation of platelets in ITP children was low. Decreased platelet function, platelet parameters and platelet glycoproteins may be used as markers for monitoring the treatment efficacy in ITP children. PMID:27431926

  2. 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...

  3. 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.

  4. 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)

  5. 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

  6. 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

  7. 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

  8. 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 ...

  9. 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.

  10. 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...

  11. 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.

  12. Crocin prevents sesamol-induced oxidative stress and apoptosis in human platelets.

    Science.gov (United States)

    Thushara, Ram M; Hemshekhar, Mahadevappa; Paul, Manoj; Shanmuga Sundaram, Mahalingam; Shankar, Rohith L; Kemparaju, Kempaiah; Girish, Kesturu S

    2014-10-01

    Recent studies have reported the platelet proapoptotic propensity of plant-derived molecules such as, resveratrol, thymoquinone, andrographolide and gossypol. Meanwhile, there were also reports of phytochemicals such as cinnamtannin B1, which shows antiapoptotic effect towards platelets. Platelets are mainly involved in hemostasis, thrombosis and wound healing. However, altered platelet functions can have serious pathological outcomes that include cardiovascular diseases. Platelets are sensitive to external and internal stimuli including therapeutic and dietary components. The anuclear platelets do undergo apoptosis via mitochondrial pathway. However, exaggerated rate of platelet apoptosis could lead to thrombocytopenia and other bleeding disorders. The present study deals with ameliorative efficacy of crocin on sesamol-induced platelet apoptosis. The antiapoptotic property of crocin and the proapoptotic tendency of sesamol in platelets were previously demonstrated. Therefore, it was interesting to see how these two compounds would interact and wield their effects on human platelets. Crocin effectively inhibited sesamol-induced oxidative stress on platelets, which was evidenced by the measurement of endogenously generated reactive oxygen species, particularly hydrogen peroxide, and changes in thiol levels. Further, crocin abrogated sesamol-induced biochemical events of apoptosis in platelets, which include intracellular calcium mobilization, changes in mitochondrial membrane integrity, cytochrome c release, caspase activity and phosphatidylserine externalization. Even though sesamol has proapoptotic effects on platelets, its anti-platelet activity cannot be neglected. Thus, the study proposes that sesamol could be supplemented with crocin, an approach that could not only abolish the toxic effects of sesamol on platelets, but also enhance the quality of treatment due to their synergistic action.

  13. Epithelial sodium channel modulates platelet collagen activation.

    Science.gov (United States)

    Cerecedo, Doris; Martínez-Vieyra, Ivette; Alonso-Rangel, Lea; Benítez-Cardoza, Claudia; Ortega, Arturo

    2014-03-01

    Activated platelets adhere to the exposed subendothelial extracellular matrix and undergo a rapid cytoskeletal rearrangement resulting in shape change and release of their intracellular dense and alpha granule contents to avoid hemorrhage. A central step in this process is the elevation of the intracellular Ca(2+) concentration through its release from intracellular stores and on throughout its influx from the extracellular space. The Epithelial sodium channel (ENaC) is a highly selective Na(+) channel involved in mechanosensation, nociception, fluid volume homeostasis, and control of arterial blood pressure. The present study describes the expression, distribution, and participation of ENaC in platelet migration and granule secretion using pharmacological inhibition with amiloride. Our biochemical and confocal analysis in suspended and adhered platelets suggests that ENaC is associated with Intermediate filaments (IF) and with Dystrophin-associated proteins (DAP) via α-syntrophin and β-dystroglycan. Migration assays, quantification of soluble P-selectin, and serotonin release suggest that ENaC is dispensable for migration and alpha and dense granule secretion, whereas Na(+) influx through this channel is fundamental for platelet collagen activation.

  14. 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...

  15. 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

  16. L-carnitine effectively improves the metabolism and quality of platelet concentrates during storage.

    Science.gov (United States)

    Deyhim, Mohammad Reza; Mesbah-Namin, Seyed Alireza; Yari, Fatemeh; Taghikhani, Mohammad; Amirizadeh, Naser

    2015-04-01

    Human platelets undergo structural and biochemical alternations during storage which are collectively called platelet storage lesion (PSL). PSL is characterized as metabolic and functionally changes. It causes decrease in platelet recovery and survival. Here, we evaluated the effect of L-carnitine (LC) on the metabolism, function, and mitochondrial metabolic activity of platelet during storage. Platelet-rich plasma was used to prepare platelet concentrate (PC) in Iranian Blood Transfusion Organization. For this purpose, ten PC bags from healthy donors were stored at 22 °C with gentle agitation in the presence or absence of LC. The effects of LC (15 mM) on the platelet quality were assessed by analyzing the levels of glucose, lactate, ATP, and lactate dehydrogenase (LDH) activity. Platelet aggregations induced by arachidonate and ristocetin were analyzed by aggregometer. Platelet mitochondrial melablolic activity was measured by tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide (MTT) assay; platelet count and mean platelet volume were also determined by a hematology analyzer during 5 days of PC storage. The results indicated that LC could significantly decrease lactate concentration and glucose consumption accompanied with the increased oxygen consumption in stored PC. LDH activity also less significantly increased in LC-treated PC on days 2 and 5 of storage. Platelet aggregation in response to the ristocetin and arachidonate was significantly higher in LC-treated PC than that in untreated PC on day 5 of storage. Finally, platelet mitochondrial metabolic activity less significantly decreased in LC-treated PC compared to the control group on days 2 and 5 of storage. It seems that LC would be a good additive to reduce PSL and improve the platelet metabolism and quality of the stored PC for platelet transfusion therapy.

  17. Platelet serotonin in systemic sclerosis.

    OpenAIRE

    Klimiuk, P S; Grennan, A; Weinkove, C.; Jayson, M I

    1989-01-01

    Platelet serotonin concentrations were measured in 43 patients with systemic sclerosis, in 11 patients with primary Raynaud's phenomenon, and in 38 normal controls. Patients with the CREST variant (calcinosis, Raynaud's phenomenon, oesophageal dysmotility, sclerodactyly, telangiectasia) had significantly lower platelet serotonin concentrations than normal controls. Patients with diffuse systemic sclerosis had normal platelet serotonin concentrations. In patients with CREST treatment with keta...

  18. 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

  19. Altered glycosylation of platelet-derived von Willebrand factor confers resistance to ADAMTS13 proteolysis.

    Science.gov (United States)

    McGrath, Rachel T; van den Biggelaar, Maartje; Byrne, Barry; O'Sullivan, Jamie M; Rawley, Orla; O'Kennedy, Richard; Voorberg, Jan; Preston, Roger J S; O'Donnell, James S

    2013-12-12

    Platelet-von Willebrand factor (VWF) is stored within α-granules and accounts for ∼20% of total VWF in platelet-rich plasma. This platelet-VWF pool is distinct from plasma-VWF and is enriched in high molecular weight multimers (HMWM). Previous studies have described significant functional discrepancies between platelet-VWF and plasma-VWF; however, the molecular basis of these differences is not well understood. We have characterized terminal glycan expression on platelet-VWF. Our findings demonstrate that platelet-VWF exists as a distinct natural glycoform. In particular, N-linked sialylation is markedly reduced (>50%) compared with plasma-VWF. Moreover, unlike plasma-VWF, platelet-VWF does not express AB blood group determinants, although precursor H antigen expression is similar to that on plasma-VWF. Because of this differential glycosylation, platelet-VWF exhibits specific resistance to ADAMTS13 proteolysis. Thus platelet activation at sites of vascular injury results in the release of high local concentrations of HMWM platelet-VWF that is more resistant to ADAMTS13, thereby facilitating platelet-plug formation. PMID:24106205

  20. 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

  1. 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

  2. PLATELET RICH FIBRIN: A PROMISING INNOVATION IN REGENERATIVE THERAPY

    Directory of Open Access Journals (Sweden)

    Arun

    2015-04-01

    Full Text Available Platelets can play a crucial role in regenerative therapy as they are reservoirs of growth factors and cytokines which are the key factors for regeneration of the bone and maturation of the soft tissue. Platelet - rich fibr in (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. Platelet - rich fibrin (PRF is autologous plate let concentrates prepared from patient’s own blood. It is a natural fibrin - based biomaterial prepared from an anticoagulant - free blood harvest without any artificial biochemical modification that allows obtaining fibrin membranes enriched with platelets a nd growth factors. Evidence from the literature suggests the potential role of PRF in regeneration and tissue engineering. The slow polymerisation during centrifugation and fibrin - based structure makes PRF a better healing biomaterial than PRP and other fi brin adhesives. The purpose of this review article is to describe the novel second - generation platelet concentrate PRF, which is an improvement over the traditionally prepared PRP for use in regenerative dentistry.

  3. 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

  4. 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

  5. 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

  6. 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.)

  7. 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.)

  8. 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

  9. Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial.

    Science.gov (United States)

    Madurantakam, Parthasarathy; Yoganarasimha, Suyog; Hasan, Fadi K

    2015-09-29

    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.

  10. Inherited disorders of hemostasis in dogs and cats.

    Science.gov (United States)

    Barr, James W; McMichael, Maureen

    2012-05-01

    Inherited disorders of hemostasis encompass abnormalities in primary hemostasis, coagulation, and fibrinolysis resulting from genetic mutations. There is significant variation in the phenotype expressed ranging from life limiting to the absence of overt clinical signs. Von Willebrand disease is the most common primary hemostatic disorder in dogs, and hemophilia A is the most common coagulation factor disorder. The diagnosis of inherited bleeding disorders is made by functional and/or quantitative evaluation. Genetic testing has added to the knowledge base, allowing prevention through targeted breeding. Avoidance of trauma and injury is paramount in the prevention of bleeding in animals diagnosed with inherited hemostatic disorders. Current therapeutic options include platelet transfusions, broad replacement of coagulation factors (e.g., plasma), targeted factor replacement (e.g., cryoprecipitate), antifibrinolytic agents and specific factor replacement, and treatment of the symptoms (i.e., bleeding) with blood transfusions.

  11. 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

  12. 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.

  13. 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-G...

  14. Platelet microbicidal activity is an important defense factor against viridans streptococcal endocarditis

    NARCIS (Netherlands)

    Krijgsveld, J; Joldersma, W; Zaat, SAJ; van der Werff, J.

    2001-01-01

    To study the role of platelet microbicidal activity in host defense against infective endocarditis (IE) due to viridans streptococci (VS), the susceptibility to platelet releasate of blood and oral VS isolates from patients with and without IE was compared. The influence of neutralization of platele

  15. Managing pregnancy with HIV, HELLP syndrome and low platelets.

    Science.gov (United States)

    Onyangunga, O A; Moodley, J

    2012-02-01

    Management of pregnancies with human immunodeficiency virus, haemolytic anaemia, elevated liver enzymes, low platelets (HELLP) syndrome, and low platelets presents complexities in investigations and treatments, because these conditions and their treatment affect the mother and baby. Low platelets in severe pre-eclampsia, eclampsia and HELLP syndrome are relatively common, and should be detected early once the diagnosis of pre-eclampsia, HELLP syndrome, or both, are made. The mainstay of treatment is lowering of high blood pressure with rapid-acting antihypertensive agents, prevention of convulsions or further seizures with MgSO(4), use of steroids for fetal lung maturity if necessary, followed by delivery of the baby. The use of high-dose steroids for the rapid recovery of maternal platelet counts is controversial, and should not be used routinely in women with HELLP syndrome. The use of platelet transfusion in women with severe pre-eclampsia, eclampsia and HELLP syndrome is a temporising measure, and should only be justified if the clinical circumstances warrant their use (e.g. before caesarean section when the woman has a low platelet count with evidence of bruising or bleeding from venepuncture sites). Low platelets may be an isolated finding in asymptomatic pregnant women and warrant the offer of a human immunodeficiency virus test, as it may be the first sign of this infection. Isolated low platelets may also indicate gestational thrombocytopaenia or idiothrombocytopaenic purpura. Gestational thrombocytopaenia is a benign condition and a diagnosis of exclusion. All clinicians should be aware that low platelets warrant further investigations because of the above-mentioned issues.

  16. Systems Biology of Platelet-Vessel Wall Interactions.

    Directory of Open Access Journals (Sweden)

    Scott L. Diamond

    2013-08-01

    Full Text Available Blood Systems Biology seeks to quantify outside-in signaling as platelets respond to numerous external stimuli, typically under flow conditions. Platelets can activate via GPVI collagen receptor and numerous G-protein coupled receptors (GPCRs responsive to ADP, thromboxane, thrombin, and prostacyclin. A bottom-up ODE approach allowed prediction of platelet calcium and phosphoinositides following P2Y1 activation with ADP, either for a population average or single cell stochastic behavior. The homeostasis assumption (i.e. a resting platelet stays resting until activated was particularly useful in finding global steady states for these large metabolic networks. Alternatively, a top-down approach involving Pairwise Agonist Scanning allowed large data sets of measured calcium mobilization to predict an individual’s platelet responses. The data was used to train Neural Network (NN models of signaling to predict patient-specific responses to combinatorial stimulation. A kinetic description of platelet signaling then allows prediction of inside-out activation of platelets as they experience the complex biochemical milieu at the site of thrombosis. Multiscale lattice kinetic Monte Carlo (LKMC utilizes these detailed descriptions of platelet signaling under flow conditions where released soluble species are solved by finite element method and the flow field around the growing thrombus is updated using computational fluid dynamics or lattice Boltzmann method. Since hemodynamic effects are included in a multiscale approach, thrombosis can then be predicted under arterial and venous thrombotic conditions for various anatomical geometries. Such systems biology approaches accommodate the effect of anti-platelet pharmacological intervention where COX1 pathways or ADP signaling are modulated in a patient-specific manner.

  17. 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.

  18. 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.

  19. 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:

  20. 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.

  1. 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.

  2. Detection and identification of platelet antibodies and antigens in the clinical laboratory.

    Science.gov (United States)

    Curtis, B R; McFarland, J G

    2009-01-01

    As a result of the unique functional properties of platelets, more-robust methods were required for detection of antibodies raised against them. Immunofluorescence detection by flow cytometry, solid-phase red cell adherence, and antigen capture ELISAs are some of the current tests that have been developed to meet the challenges of platelet antibody detection and identification and antigen phenotyping. Recently developed protein liquid bead arrays are becoming the next-generation platelet antibody tests. Fueled by development of PCR and determination of the molecular basis of the PlA1 human platelet antigen (HPA), serologic platelet typing has now been replaced by genotyping of DNA. Allele-specific PCR, melting curve analysis, and 5'-nuclease assays are now evolving into more high-throughput molecular tests. Laboratory testing for the diagnosis of immune platelet disorders has advanced considerably from its humble beginnings.

  3. 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.

  4. Accuracy of Platelet Counting by Optical and Impedance Methods in Patients with Thrombocytopaenia and Microcytosis

    Directory of Open Access Journals (Sweden)

    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.

  5. Optimization of platelet concentrate quality: application of proteomic technologies to donor management.

    Science.gov (United States)

    Schubert, Peter; Culibrk, Brankica; Karwal, Simrath; Slichter, Sherrill J; Devine, Dana V

    2012-12-01

    Quality management of blood products is essential for blood banking. It is influenced by both processing and donor characteristics and assured by monitoring routine in vitro parameters to defined product specifications. However, these measures correlate poorly with the in vivo behavior of transfused platelets and cannot be used to select optimal donors. Since radiolabeled platelet recovery and survival studies are expensive and time consuming, there is an ongoing search for simpler measures that predict platelet transfusion outcomes. We performed a pilot study using semi-qualitative proteomics to assess changes in the platelet protein profile of donors with either acceptable or unacceptable in vivo radiolabeled autologous platelet recovery and survival measurements. Proteins changing during a 9-day storage period included cytoskeletal elements talin, vinculin and moesin as well as signal transduction proteins 14-3-3, RhoGDI and Rap1. Two of nine donations exhibited a decrease in these proteins and poor in vivo platelet recovery and survival whereas the remaining donors showed acceptable platelet recovery and survival and expected protein profiles. Analyses revealed a significant correlation between protein levels of Rap1 and RhoGDI during storage and platelet recovery and survival. This study provides for the first time preliminary data showing evidence of the utility of protein profiling to predict platelet transfusion quality. This article is part of a Special Issue entitled: Integrated omics.

  6. 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 q