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Sample records for automated platelet counting

  1. Is automated platelet counting still a problem in thrombocytopenic blood?

    PubMed

    Oliveira, Raimundo Antônio Gomes; Takadachi, Maria Mariko; Nonoyama, Kimiyo; Barretto, Orlando César de Oliveira

    2003-01-02

    Reliable platelet counting is crucial for indicating prophylactic platelet transfusion in thrombocytopenic patients. To evaluate the precision and accuracy of platelet counting for thrombocytopenic patients, using four different automated counters in comparison with the Brecher & Cronkite reference method recommended by the International Committee for Standardization in Hematology (ICSH). Automated platelet counting assessment in thrombocytopenic patients. Hematology Laboratory, Hospital do Servidor Público Estadual de São Paulo, and the Hematology Division of Instituto Adolfo Lutz, São Paulo, SP, Brazil. Brecher & Cronkite reference method and four different automated platelet counters. 43 thrombocytopenic patients with platelet counts of less than 30,000/microliter. The ADVIA-120 (Bayer), Coulter STKS, H1 System (Technicom-Bayer) and Coulter T-890 automatic instruments presented great precision and accuracy in relation to laboratory thrombocytopenic samples obtained by diluting blood from normal donors. However, when thrombocytopenic patients were investigated, all the counters except ADVIA (which is based on volume and refraction index) showed low accuracy when compared to the Brecher & Cronkite reference method (ICSH). The ADVIA counter showed high correlation (r = 0.974). However, all counters showed flags in thrombocytopenic samples. The Brecher & Cronkite reference method should always be indicated in thrombocytopenic patients for platelet counts below 30,000 plt/microliter obtained in one dimensional counters.

  2. Evaluation of a semi-automated platelet-counting system.

    PubMed Central

    Rowan, R M; Fraser, C; Gray, J H; McDonald, G A

    1977-01-01

    Coulter Electronics Ltd have produced a semi-automated platelet-counting system. Platelet-rich plasma may be obtained either by tube sedimentation or by means of the Thrombo-fuge, the latter being an instrument designed to produce accelerated sedimentation. The instrument is linear over the entire range of platelet counts, and machine reproducibility is good. Comparison of machine-rated with visual counts satisfied statistical evaluation. The technique can be handled by one operator and platelet counts can be achieved at the rate of 30 per hour by both methods although individual counts on the Thrombo-fuge may be obtained in approximately one-quarter of the time required for tube sedimentation. The throughput using the Thrombo-fuge could certainly be doubled were two sample plates supplied. Few problems were encountered during the evaluation and most could be avoided by meticulous technique. Visual counts must be performed when the sample haematocrit is greater than 50%-Discrepant counts have been obtained in patients with white cell counts exceeding 50 X 10(9)/1 and in patients with giant platelets. ESR elevation for any reason does not lead to serious discrepancy in results. The incidence of platelet clumping due to the presence of platelet agglutinins and of microclot formation due to inadequate mixing is probably much higher than is commonly thought, and certainly peripheral blood film scrutiny should never be omitted in patients with low counts. Careful examination of peripheral blood films must be combined with instrument counting for some time lest further causes of discrepant counting emerge. PMID:856881

  3. Platelet counting in platelet concentrates with various automated hematology analyzers.

    PubMed

    Dijkstra-Tiekstra, Margriet J; Kuipers, Willeke; Setroikromo, Airies C; de Wildt-Eggen, Janny

    2007-09-01

    Hematology analyzers use impedance, optical, and/or immunologic techniques for counting platelets (PLTs). PLT counting in whole blood has been validated thoroughly; however, this is not the case for PLT counting in PLT concentrates (PCs), in which red cells (RBCs) are absent. Therefore, this study is focused on PLT counting in PCs to study use of ethylenediaminetetraacetate (EDTA), carryover, and accuracy of the analyzers. In total six hematology analyzers (AcT 8, Beckman Coulter; ADVIA 2,120, Bayer; Cell-Dyn 4,000, Abbott; Onyx, Beckman Coulter; K4,500, Sysmex; and XT 2,000i, Sysmex) were tested for PLT counting. PC samples with various PLT concentrations were made (0-1,700 x 10(9)/L) and measured 10 times. Carryover was determined five times. PC samples (1,000 x 10(9) PLTs/L) in EDTA tubes showed significantly higher PLT counts than samples in "dry" tubes for all analyzers except for the Cell-Dyn 4,000 with the impedance technique. Carryover was not more than 0.3 percent for all analyzers. The K4,500 showed the most accurate results, whereas the Cell-Dyn 4,000 with the impedance technique had low accuracy due to an overestimation of more than 20 percent. Most tested analyzers seemed to be suitable for counting PLTs in PCs. All hematology analyzers should be validated for counting PLTs in absence of RBCs as is the case in PCs, in addition to validation of PLT counting in whole blood.

  4. [Automated measurement of reticulocyte count by flow cytometry. II: Analysis of the blood containing abnormal erythrocytes or giant platelets].

    PubMed

    Oyamatsu, T; Shimizu, N; Takeuchi, K; Yamamoto, M; Kawai, Y; Watanabe, K; Iri, H

    1989-07-01

    We have examined the influence of erythrocytes containing inclusion bodies, nucleated red cells or giant platelets on the measurement of reticulocyte count by automated machine, R-1000. Correlation of the reticulocyte count between automated and conventional method was extremely good in the blood containing red cells with Jolly bodies, Pappenheimer bodies or basophilic stippling . However, correlation was poor when the sample contained the nucleated red cells. Reticulocyte count was decreased in the blood with significant amounts of nucleated red cells. Since nucleated red cells themselves are not counted as reticulocytes in the machine, this was considered to be due to increased young reticulocytes which frequently appeared with nucleated red cells. Both cold agglutinated red cells and giant platelets apparently influenced the reticulocyte count by the R-1000. These results suggest that red cells with Jolly bodies, Pappenheimer bodies or basophilic stippling do not influence the automatic counting of reticulocytes. Although nucleated red cells, cold agglutinated red cells and giant platelets affected the reticulocyte count, the machine shows abnormal flags in most of above cases (except highly agglutinated red cells), so that one can recount reticulocytes by conventional method. We conclude the machine can safely count the reticulocytes even in the blood containing abnormal red cells or platelets.

  5. Performance evaluation of platelet counting by novel fluorescent dye staining in the XN-series automated hematology analyzers.

    PubMed

    Tanaka, Yuzo; Tanaka, Yumiko; Gondo, Kazumi; Maruki, Yoshiko; Kondo, Tamiaki; Asai, Satomi; Matsushita, Hiromichi; Miyachi, Hayato

    2014-09-01

    Conventional automated hematology analyzers have limitations in platelet measurements such as poor accuracy and precision in the low count range and interference by nonplatelet particles. In order to improve it, the newly developed XN-Series automated hematology analyzers (Sysmex Corporation, Kobe, Japan) have been installed with a new dedicated channel for platelet analysis (PLT-F), which is based on a fluorescence flow cytometry method with uses of a novel fluorescent dye specifically staining platelets. We evaluated the basic performance of this new PLT-F channel. Basic performance of the PLT-F channel in within-run reproducibility and assay linearity was studied using standard methods. Correlation was studied between PLT-F and a conventional automated hematology analyzer (XE-2100) and immunoplatelet analysis using anti-CD61 monoclonal antibody (Cell-Dyn Sapphire; Abbott Laboratories). The assay interference by nonplatelet particles such as fragmented red and white blood cells was evaluated by using clinical samples, respectively, from burn injury and acute leukemia. Basic performance of the PLT-F platelet counting was satisfactory in within-run reproducibility, linearity and correlation with the conventional analyzer. The correlation was satisfactory also with the immunoplatelet analysis, even for samples from a patient with burn injury, and those with white blood cell fragments displayed, platelet abnormal flag and low platelet counts (<50 × 10(9)/l). The platelet counting performance of the PLT-F channel of the XN Series had improved accuracy and precision in the low range and in abnormal samples, avoiding the interference by nonplatelet particles. © 2014 Wiley Periodicals, Inc.

  6. Comparison of platelet counting technologies in equine platelet concentrates.

    PubMed

    O'Shea, Caitlin M; Werre, Stephen R; Dahlgren, Linda A

    2015-04-01

    (1) To compare the performance of 4 platelet counting technologies in equine platelet concentrates and (2) to evaluate the ability of the Magellan platelet rich plasma (PRP) system to concentrate equine platelets. Experimental study to assess method agreement. Adult mixed breed horses (n = 32). Acid citrate dextrose-A anti-coagulated whole blood was collected and PRP produced using the Magellan system according to the manufacturer's instructions. Platelets were quantified using 4 counting methods: optical scatter (Advia 2120), impedance (CellDyn 3700), hand counting, and fluorescent antibody flow cytometry. Platelet concentrations were compared using Passing and Bablok regression analyses and mixed model ANOVA. Significance was set at P < .05. Platelet concentrations measured in identical PRP samples were consistently higher for the Advia 2120 than the CellDyn 3700. Systematic and proportional biases were observed between these 2 automated methods when analyzed by regression analysis of the larger sample size. No bias (systematic or proportional) was observed among any of the other counting methods. Despite the bias detected between the 2 automated systems, there were no significant differences on average among the 4 counting methods evaluated, based on the ANOVA. The Magellan system consistently generated high platelet concentrations as well as higher than expected WBC concentrations. The Magellan system delivered desirably high platelet concentrations; however, WBC concentrations may be unacceptably high for some orthopedic applications. All 4 platelet counting methods tested were equivalent on average and therefore suitable for quantifying platelets in equine PRP used for clinical applications. © Copyright 2014 by The American College of Veterinary Surgeons.

  7. [Platelet count in the cat].

    PubMed

    Moritz, A; Hoffmann, C

    1997-11-01

    The technique of collecting blood samples is primarily responsible for the appearance of platelet-agglomeration in cats. Blood obtained by the conventional way ("one syringe technology", drips of blood) caused in 52% of the cases an activation of the large and therefore active thrombocytes however. Rejection of the first 2-5 ml blood for the platelet count ("two syringe technology") reduced the rate of platelet-agglomeration significantly. No big differences in platelet-agglomeration were found with regard to the place used for collecting blood (V. cephalica antebrachii/V. jugularis). Platelet-agglutination was observed with Li-Heparin, K-EDTA, Na-Citrat or ACD anticoagulated blood samples. Citrat (Na-Citrat, ACD) seemed to have a stabilizing effect on feline thrombocytes as has been described for human thrombocytes. The platelet count in cats should be performed within 30 minutes.

  8. Producing accurate platelet counts for platelet rich plasma: validation of a hematology analyzer and preparation techniques for counting.

    PubMed

    Woodell-May, Jennifer E; Ridderman, Dayna N; Swift, Matthew J; Higgins, Joel

    2005-09-01

    Platelet rich plasma (PRP) has been shown to clinically accelerate healing of both soft and hard tissues. As a result, it has gained increasing popularity. However, the clinical effectiveness of each type of PRP preparation method can vary in technique and efficiency, and current methods to evaluate the platelet concentration efficiency of PRP systems have several limitations. Therefore, the purpose of this study was to validate an automated hematology analyzer, the Cell-Dyn 3700, to accurately count platelets in concentration ranges of approximately 2,000,000-4,800,000 platelets/microL. PRP platelets were counted by way of a manual counting method and on the Cell-Dyn 3700, and the statistical evaluation indicated no difference between the groups (P > 0.05). Dilution of the PRP was not required, and accurate platelet counts could be achieved up to platelet concentrations of 4,800,000 platelets/microL. PRPs must be resuspended on a rocker for at least 5 minutes before platelet counts, and the entire PRP sample must be resuspended to allow for equal distribution of platelets before counting. With use of the validated Cell-Dyn 3700, a platelet concentrate system was used to prepare 153 PRPs. The baseline whole blood platelet concentration (328,000 platelets/microL +/- 69,000 platelets/microL) and the average PRP samples (2,645,000 platelets/microL +/- 680,000 platelets/microL) were compared, resulting in an eightfold increase in concentration and an average platelet percent recovery of approximately 76%. Automated hematology analyzers can be used to accurately count platelets in PRP given the system has been validated appropriately and the PRP samples are prepared properly to provide adequate platelet suspension.

  9. Variations of the Platelet Count in Disease

    PubMed Central

    Marchasin, Sidney; Wallerstein, Ralph O.; Aggeler, Paul M.

    1964-01-01

    Platelet counts were obtained in 675 patients with different hematological and other medical disorders. An indirect venous blood dry slide method which gave a normal range of 200 to 400 × 103 per cu mm was used. Platelet counts varied considerably in disease: In 20 patients, exclusive of myeloproliferative disorders, platelet counts in excess of 1,000 × 103 per cu mm were observed; in 20 patients, exclusive of leukemia and megaloblastic anemia, platelet counts were below 100 × 103 per cu mm. In general, platelet counts varied with the leukocyte count, but not with the degree of anemia. PMID:14180504

  10. Recovery of Platelet Count among Apheresis Platelet Donors

    PubMed Central

    Radhakrishnan, Krishnamoorthy; Anandan, Ashwin; Panicker, Vinod Kumar

    2016-01-01

    Introduction Increase in awareness regarding use of single donor platelets and the availability of technology has resulted in increased platelet pheresis procedures. The interval between two succesive plateletpheresis donations is much less compared to whole blood donations. Plateletpheresis procedures are associated with short term and long term adverse events. The effect of plateletpheresis on haematopoietic system remains significant. Aim To study the recovery of platelet count to baseline in plateletpheresis donors. Materials and Methods Fifty, first time apheresis donors were followed for platelet count recovery. Platelet count was measured before donation and at 30 minutes, 48 hours, 7th day and 14th day post-donation. Donor platelet count recovery to baseline was observed during the two week period. Results were analysed statistically, p<0.05 was considered statistically significant. Results Platelet count recovered to baseline by 7th day post-donation in 50% of donors in groups I (Pre-donation platelet count 1.5 lacs/μl to 2.2 lacs/μl) and II (Donors with platelet count >2.2 lacs/μl to 2.75 lacs/μl), 30% of donors in group III (Donors with platelet count >2.75 lacs/μl to 3.5 lacs/μl) of the donors. Donor’s platelet count recovered to baseline in 85% of donors by day 14 in across the three groups. Recruitment of platelets from spleen was observed in donors with pre-donation platelet count on the lower limit of normal. Conclusion By day 7, donor’s platelet count recovered to baseline in majority of the donors. Allowing enough recovery periods for donor platelet count, the minimum interval between two apheresis donations can be 7 days till more prospective studies conclude on the frequency and minimum interval between plateletpheresis donations. PMID:28208861

  11. Development and evaluation of a novel in-clinic automated hematology analyzer, ProCyte Dx, for canine erythrocyte indices, leukogram, platelet counts and reticulocyte counts.

    PubMed

    Fujino, Yasuhito; Nakamura, Yoichi; Matsumoto, Hideaki; Fukushima, Kenjiro; Takahashi, Masashi; Ohno, Koichi; Tsujimoto, Hajime

    2013-11-01

    A novel hematology analyzer for small animal medicine, ProCyte Dx, was developed from combination of the fluorescence laser flow cytometry and laminar flow impedance technologies, and its accuracy was evaluated by comparing with the conventional impedance-based hematology analyzer, pocH-100iV Diff, or microscopic manual cell counting methods with staining blood smears in the canine blood. Blood samples of 59 dogs were hematologically analyzed and compared by Pearson's correlation coefficients. Analyses between the two analyzers showed excellent correlation in RBC (r=0.998), HGB (r=0.999), HCT (r=0.998), MCV (r=0.994), MCH (r=0.974), MCHC (r=0.906), WBC (r=0.998) and PLT (r=0.993). Analyses between ProCyte Dx and microscopic manual counting results showed excellent correlation in neutrophils (r=0.920), lymphocytes (r=0.913) and reticulocyte percentages (r=0.924), good correlation in eosinophils (r=0.815) and reticulocyte numbers (r=0.850) and fair correlation in monocytes (r=0.770). The present study indicates that ProCyte Dx is acceptably accurate and can be a powerful tool for canine clinical medicine.

  12. Development and Evaluation of a Novel In-Clinic Automated Hematology Analyzer, ProCyte Dx, for Canine Erythrocyte Indices, Leukogram, Platelet Counts and Reticulocyte Counts

    PubMed Central

    FUJINO, Yasuhito; NAKAMURA, Yoichi; MATSUMOTO, Hideaki; FUKUSHIMA, Kenjiro; TAKAHASHI, Masashi; OHNO, Koichi; TSUJIMOTO, Hajime

    2013-01-01

    ABSTRACT A novel hematology analyzer for small animal medicine, ProCyte Dx, was developed from combination of the fluorescence laser flow cytometry and laminar flow impedance technologies, and its accuracy was evaluated by comparing with the conventional impedance-based hematology analyzer, pocH-100iV Diff, or microscopic manual cell counting methods with staining blood smears in the canine blood. Blood samples of 59 dogs were hematologically analyzed and compared by Pearson’s correlation coefficients. Analyses between the two analyzers showed excellent correlation in RBC (r=0.998), HGB (r=0.999), HCT (r=0.998), MCV (r=0.994), MCH (r=0.974), MCHC (r=0.906), WBC (r=0.998) and PLT (r=0.993). Analyses between ProCyte Dx and microscopic manual counting results showed excellent correlation in neutrophils (r=0.920), lymphocytes (r=0.913) and reticulocyte percentages (r=0.924), good correlation in eosinophils (r=0.815) and reticulocyte numbers (r=0.850) and fair correlation in monocytes (r=0.770). The present study indicates that ProCyte Dx is acceptably accurate and can be a powerful tool for canine clinical medicine. PMID:23811854

  13. Relationships between platelet counts, platelet volumes and reticulated platelets in patients with ITP: evidence for significant platelet count inaccuracies with conventional instrument methods.

    PubMed

    Diquattro, M; Gagliano, F; Calabrò, G M; Tommasi, M; Scott, C S; Mancuso, G; Palma, B; Menozzi, I

    2009-04-01

    The platelet count has a primary role in the diagnosis and treatment of idiopathic thrombocytopenic purpura (ITP). This study analysed the accuracy of ITP patient platelet counts determined by Abbott CD-Sapphire (impedance/optical) and Bayer Advia 120 (optical) analyses, compared with a reference immunoplatelet method. Instrument platelet estimates showed broad equivalence in the higher range of observed values, but significant discrepancies against the immunoplatelet count were seen when platelet counts were <10 x 10(9)/l. CD-Sapphire mean platelet volume (MPV) results revealed increased (>12 fl) platelet volumes in eight of eight ITP patients with counts of <20 x 10(9)/l compared with 6/6 and 5/13 patients with platelet counts of 20-50 and >50 x 10(9)/l. In contrast, Bayer Advia MPV values showed no relationship with the platelet count. Increased reticulated platelets were associated with an increasing CD-Sapphire MPV (R(2) = 0.61) and a decreasing platelet count. High (>40%) reticulated platelet values were seen in 9/9 patients with immunoplatelet counts of <20 x 10(9)/l compared with 0/19 patients with platelet counts above 20 x 10(9)/l. There may be a need for caution in the interpretation of platelet counts in ITP patients obtained with conventional instrument methods, and therapeutic decisions should ideally be validated by reference immunoplatelet procedures.

  14. Automated platelet counters: a comparative evaluation of latest instrumentation.

    PubMed

    Mayer, K; Chin, B; Magnes, J; Thaler, H T; Lotspeich, C; Baisley, A

    1980-08-01

    An extensive evaluation of performance characteristics and accuracy of clinical results for two automated multiparameter whole-blood cell counters (the Coulter Counter Model S-Plus and the Ortho ELT-8) and two single-parameter semiautomated platelet counters (the J. T. Baker MK-4/HC and the Clay-Adams Ultra-Flo 100) is described. Results of comparative assays performed on more than 1,200 clinical specimens are analyzed. These results are compared with manual determinations where appropriate. Particular attention is accorded to the accuracy of platelet counts, especially at abnormal levels below 70 X 10(3)/cu mm, where falsely elevated platelet counts may lead to serious clinical consequences. Both multiparameter instruments yielded accurate results, with the exception of low values reported by the ELT-8 for mean corpuscular volumes above 100 cu micrometer. Results for platelet counts were accurate for most specimens on all four instruments; the ELT-8 was the most reliable (P < 0.01), especially for the critically low counts. Although no instrument is infallible in determining platelet counts at all levels, the authors conclude that addition of platelet-counting capability represents a significant advancement over existing instrumentation.

  15. Manual and automated reticulocyte counts.

    PubMed

    Simionatto, Mackelly; de Paula, Josiane Padilha; Chaves, Michele Ana Flores; Bortoloso, Márcia; Cicchetti, Domenic; Leonart, Maria Suely Soares; do Nascimento, Aguinaldo José

    2010-12-01

    Manual reticulocyte counts were examined under light microscopy, using the property whereby supravital stain precipitates residual ribosomal RNA versus the automated flow methods, with the suggestion that in the latter there is greater precision and an ability to determine both mature and immature reticulocyte fractions. Three hundred and forty-one venous blood samples of patients were analyzed of whom 224 newborn and the rest adults; 51 males and 66 females, with ages between 0 and 89 years, as part of the laboratory routine for hematological examinations at the Clinical Laboratory of the Hospital Universitário do Oeste do Paraná. This work aimed to compare manual and automated methodologies for reticulocyte countings and evaluate random and systematic errors. The results obtained showed that the difference between the two methods was very small, with an estimated 0·4% systematic error and 3·9% random error. Thus, it has been confirmed that both methods, when well conducted, can reflect precisely the reticulocyte counts for adequate clinical use.

  16. Changes in Platelet Count and Size Indices in Adolescent Patients With Anorexia Nervosa.

    PubMed

    Oświęcimska, Joanna; Malczyk, Żaneta; Szymlak, Agnieszka; Mikołajczak, Agata; Ziora, Katarzyna; Zamlynski, Jacek; Machura, Edyta; Zajac, Piotr; Koczy, Bogdan; Kasperska-Zajac, Alicja

    2017-09-01

    The significance of platelet size indices has not been widely analyzed in anorexia nervosa (AN). It seems important to get more knowledge on the easily available indices of platelet function obtained by routine complete blood count analysis in patients with AN. We analyzed platelet count (PLT), platelet distribution width (PDW), and mean platelet volume using an automated blood cell counter in 25 females with AN and healthy age- and gender-matched nonatopic controls. Mean PLT was significantly lower in patients with AN than in the control group. Platelet distribution width values in patients with AN were significantly higher than those in the controls. Platelet distribution width values significantly correlated with the disease duration and rate of body weight loss in the anorectic patients. Anorexia nervosa in adolescents is associated with a decrease in PLT along with an increased PDW, which may be an indicator of dysregulated thrombopoiesis.

  17. Platelet count and platelet indices in women with preeclampsia.

    PubMed

    AlSheeha, Muneera A; Alaboudi, Rafi S; Alghasham, Mohammad A; Iqbal, Javed; Adam, Ishag

    2016-01-01

    Although the exact pathophysiology of preeclampsia is not completely understood, the utility of different platelets indices can be utilized to predict preeclampsia. To compare platelet indices, namely platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and PC to MPV ratio in women with preeclampsia compared with healthy controls. Qassim Hospital, Kingdom of Saudi Arabia. A case-control study. Sixty preeclamptic women were the cases and an equal number of healthy pregnant women were the controls. There was no significant difference in age, parity, and body mass index between the study groups. Sixteen and 44 of the cases were severe and mild preeclampsia, respectively. There was no significant difference in PDW and MPV between the preeclamptic and control women. Both PC and PC to MPV ratios were significantly lower in the women with preeclampsia compared with the controls. There was no significant difference in the PC, PDW, MPV, and PC to MPV ratio when women with mild and severe preeclampsia were compared. Using receiver operating characteristic (ROC) curves, the PC cutoff was 248.0×10(3)/µL for diagnosis of pre-eclampsia (P=0.019; the area under the ROC curve was 62.4%). Binary regression suggests that women with PC <248.010×10(3)/µL were at higher risk of preeclampsia (odds ratio =2.2, 95% confidence interval =1.08-4.6, P=0.03). The PC/MPV cutoff was 31.2 for diagnosis of preeclampsia (P=0.035, the area under the ROC curve was 62.2%). PC <248.010×10(3)/µL and PC to MPV ratio 31.2 are valid predictors of preeclampsia.

  18. Platelet count and platelet indices in women with preeclampsia

    PubMed Central

    AlSheeha, Muneera A; Alaboudi, Rafi S; Alghasham, Mohammad A; Iqbal, Javed; Adam, Ishag

    2016-01-01

    Background Although the exact pathophysiology of preeclampsia is not completely understood, the utility of different platelets indices can be utilized to predict preeclampsia. Objective To compare platelet indices, namely platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and PC to MPV ratio in women with preeclampsia compared with healthy controls. Setting Qassim Hospital, Kingdom of Saudi Arabia. Design A case–control study. Sixty preeclamptic women were the cases and an equal number of healthy pregnant women were the controls. Results There was no significant difference in age, parity, and body mass index between the study groups. Sixteen and 44 of the cases were severe and mild preeclampsia, respectively. There was no significant difference in PDW and MPV between the preeclamptic and control women. Both PC and PC to MPV ratios were significantly lower in the women with preeclampsia compared with the controls. There was no significant difference in the PC, PDW, MPV, and PC to MPV ratio when women with mild and severe preeclampsia were compared. Using receiver operating characteristic (ROC) curves, the PC cutoff was 248.0×103/µL for diagnosis of pre-eclampsia (P=0.019; the area under the ROC curve was 62.4%). Binary regression suggests that women with PC <248.010×103/µL were at higher risk of preeclampsia (odds ratio =2.2, 95% confidence interval =1.08–4.6, P=0.03). The PC/MPV cutoff was 31.2 for diagnosis of preeclampsia (P=0.035, the area under the ROC curve was 62.2%). Conclusion PC <248.010×103/µL and PC to MPV ratio 31.2 are valid predictors of preeclampsia. PMID:27920548

  19. A flow cytometric method for platelet counting in platelet concentrates.

    PubMed

    van der Meer, Pieter F; Karssing-van Leeuwen, Willy; Kurtz, Jim; Spengler, Hans-Peter; Blair, AbbeJane; Devine, Dana; Harrison, Paul; Lambrecht, Bernd; VandenBroeke, Tania; de Wildt, Janny; de Korte, Dirk

    2012-01-01

    The platelets (PLTs) in PLT concentrates are counted with hematology analyzers, but varying results among different hematology analyzers are observed, making comparisons very difficult. Due to the absence of red blood cells in PLT concentrates, the International Council for Standardization in Hematology (ICSH) reference method was modified to be used for PLT concentrates and validated in an international comparative study. Five PLT samples were shipped to eight participating centers of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative and counted on the same day. PLTs were stained with fluorescein isothiocyanate-labeled anti-CD41a in tubes (TruCount, BD Biosciences), measured on a flow cytometer, and analyzed with a uniform template. These samples were also counted on 15 hematology analyzers. The ICSH method and newly developed BEST method yielded PLT counting results with less than 1% difference (not significant). The intercenter coefficient of variation (CV) of the BEST method was on average 6.3% versus 7.6% on average for hematology analyzers. The CV of individual hematology analyzers was on average 0.9%, which was considerably lower than for the flow cytometers with a mean of 3.7%. The BEST flow cytometric method has a smaller intercenter CV and a smaller center-to-center deviation from the group mean compared to hematology analyzers. Conversely, individual hematology analyzers are more precise than the flow cytometric method. Thus, the flow cytometric method provides a calibration tool to allow comparisons between centers, but there is no need to replace routine counting with hematology analyzers. © 2011 American Association of Blood Banks.

  20. The influence of various hematology analyzers on component platelet counts.

    PubMed

    Moroff, Gary; Sowemimo-Coker, Samuel O; Finch, Stephen; Murphy, Scott; Brandwein, Harvey; Whitbread, John; Wenz, Barry

    2005-04-01

    Hematology analyzers designed to count platelets in samples of whole blood are used to enumerate the total number of platelets in components prepared for transfusion. This report addresses the issue of variability in platelet counts obtained with different models of hematology analyzers. The influence of a common calibration procedure, involving one level of porcine platelets, on the extent of variability was also evaluated. Identical sets of samples of simulated and apheresis-derived human platelets were counted by multiple laboratories in 3 separate studies. In the first 2 exercises, 7 samples of both porcine platelets and modified goat erythrocytes with targeted platelets counts from 0.2 to 4.0 x 10(12)/L were counted without prior dilution. In both exercises, the samples were counted multiple times after routine calibration using instructions provided by the manufacturers of the various hematology analyzers used. In the second exercise, the samples were recounted after the hematology analyzers were recalibrated with a common calibrant consisting of porcine platelets at a targeted concentration of 0.5 x 10(12)/L. In the first and second exercises, 20 and 18 hematology analyzers were used, respectively. In the third exercise, 6 samples prepared from a single unit of apheresis platelets with targeted counts from 0.2 to 1.64 x 10(12)/L were shipped by an overnight courier and counted in triplicate on the day of arrival. Eleven hematology analyzers were used. The influence of recalibration was evaluated statistically by using the 95% prediction interval for the mean of a future set of observations. The platelet counts measured with a specific type of hematology analyzer provided the data to calculate the 95% prediction interval. With routine calibration, a wide variability in platelet counts was observed with all levels of both simulated and apheresis-derived human platelets. For example, with porcine platelets at a targeted level of 0.4 x 10 (12)/L, the platelet

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

    PubMed

    Du Plessis, L

    2009-09-01

    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 10(9)/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, morphometric analysis 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.

  2. Accuracy of a New Platelet Count System (PLT-F) Depends on the Staining Property of Its Reagents

    PubMed Central

    Wada, Atsushi; Takagi, Yuri; Kono, Mari; Morikawa, Takashi

    2015-01-01

    Background Platelet count is essential for the diagnosis and management of hemostasis abnormalities. Although existing platelet count methods installed in common hematology analyzers can correctly count platelets in normal blood samples, they tend to miscount platelets in some abnormal samples. The newly developed PLT-F channel in the XN-Series hematology analyzer (Sysmex) has been reported to be a reliable platelet count system, even in abnormal samples. However, how the PLT-F platelet counting system achieves such accuracy has not been described in scientific articles. Methods Isolated platelets, erythrocytes, and fragmented erythrocytes were examined using an automated hematology analyzer. The samples were labeled by combining PLT-F reagents and anti-CD62p, CD63, Grp75, Calreticulin, CD41, or CD61 antibody, and analyzed using confocal laser scanning microscopy or flow cytometry. Results The PLT-F system correctly discriminated platelets in erythrocytes. Its reagents strongly stained some intraplatelet organelles labeled with anti-Grp75, but only faintly stained the plasma membrane of both platelets and erythrocytes. Microscopic observation and flow cytometric examination revealed that all of these strongly stained cells were also labeled with platelet-specific anti-CD41 and anti-CD61 antibodies. Conclusions This study revealed that the staining property of the PLT-F reagents, by which platelets and fragmented erythrocytes are clearly distinguished, contributes to the platelet-counting accuracy of the PLT-F system. PMID:26496387

  3. Automatic platelet counting with the Coulter particle counter

    PubMed Central

    Davis, R. E.; Green, R. E.

    1967-01-01

    A method for accurately counting platelets is described using the Coulter counter model B fitted with a standard 100μ aperture tube. This enables the counter to be used for red and white cell as well as platelet counts using the same aperture tube. The method uses standard equipment except for a small inexpensive electronic speed controller. PMID:5602990

  4. The significance of platelet counts in coagulation studies.

    PubMed

    Carroll, W E; Wollitzer, A O; Harris, L; Ling, M C; Whitaker, W L; Jackson, R D

    2001-01-01

    Traditionally, the platelet count recommended for coagulation studies has been less than 10 x 10(9)/L, but the documentation for this is obscure. In the present study, platelet rich plasma (PRPs) and platelet poor plasmas (PPPs) were prepared from the same blood specimen to determine prothrombin times (PTs), International Normalized Ratios (INRs), partial thromboplastin times (PTTs), and their results compared. The measurements of all three of these parameters are not statistically or clinically significant in 100 paired comparisons. Incremented platelet count studies, selected by the number of platelets in the PRPs, showed that platelet counts of at least 199 x 10(9)/L, or perhaps even higher, did not compromise the results of PTs, INRs or PTTs. Such increased platelet counts, however, cannot be tolerated in the various studies for antiphospholipid antibodies, the Lupus Anticoagulant (LAC), or when monitoring heparin therapy with PTTs. Here, the < 10 x 10(9)/L platelet levels must be respected; otherwise the tests would be compromised by platelet-liberated phospholipid (Triplett, Brand et al., 1983) or by Platelet Factor 4, respectively.

  5. Platelets in the paediatric population: the influence of age and the limitations of automation.

    PubMed

    Felle, P; McMahon, C; Rooney, S; Donnelly, P; Ni Chonchubhair, F

    2005-08-01

    Accurate and precise platelet counting is important for the clinical management of children with platelet disorders. Current automated technologies are often unable to discriminate platelets from non-platelet particles particularly in circumstances where platelet anisocytosis is common. This study compares manual methodology and the automated technologies; impedance, optical density and CD61 immunoplatelet method (available on the Cell Dyn 4000) with the reference method of flow cytometric analysis in a paediatric population. A total of 141 samples were analysed and divided into specific age related groups and groups with thrombocytopenia and thrombocytosis. Data analysis showed that the CD61 method compared best with the reference method and this was evident in all the specified groups. The mean platelet count obtained by optical and manual methods were lower, suggesting that these methods are less reliable. The impedance count method was accurate despite its limitations. Strong correlations were observed in the 2-14 year age group but there was greater variation in the <1 month group supporting the theory that there is a greater variation in platelet characteristics in neonates. The CD61 method is the automated method of choice and would be particularly useful in the problem groups (platelet counts <50 x 10(9)/l and neonates <1 month old).

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

    PubMed

    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.

  7. Measurement of platelet aggregation, independently of patient platelet count: a flow-cytometric approach.

    PubMed

    Vinholt, P J; Frederiksen, H; Hvas, A-M; Sprogøe, U; Nielsen, C

    2017-06-01

    Essentials Platelet function may influence bleeding risk in thrombocytopenia, but useful tests are needed. A flow cytometric platelet aggregation test independent of the patient platelet count was made. Platelet aggregation was reduced in thrombocytopenic patients with hematological cancer. High platelet aggregation ruled out bleeding tendency in thrombocytopenic patients. Background Methods for testing platelet aggregation in thrombocytopenia are lacking. Objective To establish a flow-cytometric test of in vitro platelet aggregation independently of the patient's platelet count, and examine the association of aggregation with a bleeding history in thrombocytopenic patients. Patients/methods We established a flow-cytometric assay of platelet aggregation, and measured samples from healthy individuals preincubated with antiplatelet drugs, and samples from two patients with inherited platelet disorders. Then, we included 19 healthy individuals and 20 patients with platelet counts of ≤ 50 × 10(9) L(-1) , diagnosed with acute myeloid leukemia or myelodysplastic syndrome. We measured platelet aggregation and platelet activation by platelet surface expression of activated glycoprotein IIb-IIIa, P-selectin and CD63 after addition of agonists: collagen-related peptide, thrombin receptor-activating peptide (TRAP), and ADP. Results The platelet aggregation assay showed a low intraserial coefficient of variation of ≤ 3%. Similar results were obtained for platelet-rich plasma and isolated platelets at platelet counts of > 10 × 10(9) L(-1) ; otherwise, platelet isolation was required. The platelet aggregation percentage decreased with increasing antiplatelet drug concentration. Platelet aggregation in patients was reduced as compared with healthy individuals: 42% (interquartile range [IQR] 27-58) versus 66% (IQR 60-67) for TRAP; 41% (IQR 25-48) versus 70% (IQR 69-72) for collagen-related peptide; and 44% (IQR 30-53) versus 65% (IQR 46-72) for ADP. Platelet activation after

  8. Correlation between platelet count and both liver fibrosis and spleen diameter in patients with schistosomiasis mansoni.

    PubMed

    Medeiros, Tibério B; Domingues, Ana Lucia C; Luna, Carlos F; Lopes, Edmundo P

    2014-01-01

    Studies have described the correlation between platelet count and the stages of fibrosis in chronic viral hepatitis, but few publications have studied this correlation in Schistosomiasis mansoni. Therefore, this study aimed to correlate platelet count with both the periportal fibrosis pattern and spleen diameter evaluated by ultrasound exam in patients with Schistosomiasis mansoni. Patients with Schistosomiasis mansoni were evaluated by abdominal ultrasound by a single examiner for the determination of periportal fibrosis pattern (Niamey classification) and spleen diameter. Platelet counts were performed in an automated cell counter. One hundred eighty-seven patients with Schistosomiasis mansoni (mean age: 50.2 years) were included in the study, 114 of whom (61%) were women. Based on the Niamey classification, the ultrasound analysis revealed that 37, 64, 64 and 22 patients exhibited patterns C, D, E and F, respectively. In these four groups, the mean number of platelets was 264, 196, 127 and 103 x 109/L and mean spleen diameter was 9.2, 11.9, 14.9 and 16.2 centimeters, respectively. A reduction in platelet count was significantly associated with both the progression of the periportal fibrosis and the increase in spleen size. Platelet count in patients with Schistosomiasis mansoni was inversely correlated with the severity of periportal fibrosis and spleen diameter.

  9. Platelet function tests, independent of platelet count, are associated with bleeding severity in ITP.

    PubMed

    Frelinger, Andrew L; Grace, Rachael F; Gerrits, Anja J; Berny-Lang, Michelle A; Brown, Travis; Carmichael, Sabrina L; Neufeld, Ellis J; Michelson, Alan D

    2015-08-13

    Immune thrombocytopenia (ITP) patients with similarly low platelet counts differ in their tendency to bleed. To determine if differences in platelet function in ITP patients account for this variation in bleeding tendency, we conducted a single-center, cross-sectional study of pediatric patients with ITP. Bleeding severity (assessed by standardized bleeding score) and platelet function (assessed by whole blood flow cytometry) with and without agonist stimulation was evaluated in 57 ITP patients (median age, 9.9 years). After adjustment for platelet count, higher levels of thrombin receptor activating peptide (TRAP)-stimulated percent P-selectin- and activated glycoprotein (GP)IIb-IIIa-positive platelets were significantly associated with a lower bleeding score, whereas higher levels of immature platelet fraction (IPF), TRAP-stimulated platelet surface CD42b, unstimulated platelet surface P-selectin, and platelet forward light scatter (FSC) were associated with a higher bleeding score. Thus, platelet function tests related to platelet age (IPF, FSC) and activation through the protease activated receptor 1 (PAR1) thrombin receptor (TRAP-stimulated P-selectin, activated GPIIb-IIIa, and CD42b), independent of platelet count, are associated with concurrent bleeding severity in ITP. These tests may be useful markers of future bleeding risk in ITP.

  10. Flow cytometric assessment of activation of peripheral blood platelets in dogs with normal platelet count and asymptomatic thrombocytopenia.

    PubMed

    Żmigrodzka, M; Guzera, M; Winnicka, A

    2016-01-01

    Platelets play a crucial role in hemostasis. Their activation has not yet been evaluated in healthy dogs with a normal and low platelet count. The aim of this study was to determine the influence of activators on platelet activation in dogs with a normal platelet count and asymptomatic thrombocytopenia. 72 clinically healthy dogs were enrolled. Patients were allocated into three groups. Group 1 consisted of 30 dogs with a normal platelet count, group 2 included 22 dogs with a platelet count between 100 and 200×109/l and group 3 consisted of 20 dogs with a platelet count lower than 100×109/l. Platelet rich-plasma (PRP) was obtained from peripheral blood samples using tripotassium ethylenediaminetetraacetic acid (K3-EDTA) as anticoagulant. Next, platelets were stimulated using phorbol-12-myristate-13-acetate or thrombin, stabilized using procaine or left unstimulated. The expression of CD51 and CD41/CD61 was evaluated. Co-expression of CD41/CD61 and Annexin V served as a marker of platelet activation. The expression of CD41/CD61 and CD51 did not differ between the 3 groups. Thrombin-stimulated platelets had a significantly higher activity in dogs with a normal platelet count than in dogs with asymptomatic thrombocytopenia. Procaine inhibited platelet activity in all groups. In conclusion, activation of platelets of healthy dogs in vitro varied depending on the platelet count and platelet activator.

  11. [Electronic platelet counting with particular reference to thrombocytopenias (author's transl)].

    PubMed

    Kuse, R; Burmeister, H; Hausmann, K

    1977-09-29

    Platelet counts in platelet-rich plasma without hematocrit dependent correction were performed by following rapid and simple steps: 1. pre-dilution of 20 microliter of whole blood by an isotonic solution 1:25; 2. stabilized low-speed centrifugation with 55 g for 5 minutes; 3. final dilution 1 : 5000; 4. enumeration by use of a TOA platelet counter PL-100 which has been technically improved in comparison to similar machines. Erroneously high results were obtained after a too short or too low centrifugation. As reason for this artifical small pulses due to disturbances of the flow patterns around the aperture (so-called vortex-effect) can be assumed having been caused by large-volumed erythrocytes and leukocytes in the suspension. The routinely used procedure was reliable for all platelet ranges, especially in thrombocytopenias between 100 X 10(9)/l and 25 X 10(9)l. In lower ranges comparisons with visual counts are essential.

  12. The automation of routine light transmission platelet aggregation

    PubMed Central

    Lawrie, A S; Kobayashi, K; Lane, P J; Mackie, I J; Machin, S J

    2014-01-01

    Introduction The investigation of platelet function by aggregometry requires specialist equipment and is labour intensive. We have developed an automated platelet aggregation method on a routine coagulation analyser. Methods We used a CS-2000i (Sysmex) with prototype software to perform aggregation in platelet-rich plasma (PRP), using the following agonists: ADP (0.5–10 μm), epinephrine (0.5–10 μm), collagen (0.5–10 mg/μL), ristocetin (0.75–1.25 mg/mL) and arachidonic acid (0.12–1.0 mm). Platelet agonists were from Hyphen Biomed, and an AggRAM aggregometer (Helena Biosciences) was used as the reference instrument. Results CS-2000i reaction cuvette stirrer speed was found to influence reaction sensitivity and was optimized to 800 rpm. There were no clinically significant changes in aggregation response when the PRP platelet count was 150–480 x 109/L, but below this there were changes in the maximum amplitude (MA) and slope (rate). Dose response with each of the agonists was comparable between CS-2000i and an AggRAM aggregometer and normal subjects receiving antiplatelet drugs. Aggregation imprecision was similar on both the CS-2000i and AggRAM systems, with a cv for 2–5 μm ADP MA and slope varying between 3–12%. Conclusion Our preliminary studies indicated that optimal sensitivity using the CS-2000i was obtained with a reaction cuvette stirrer speed of 800 rpm and a PRP platelet count of 200–300 x 109/L; aggregation with a PRP count <100 x 109/L showed poor sensitivity. Imprecision and detection of antiplatelet drug effects was similar between the CS-2000i and AggRAM. These data demonstrate that CS-2000i is comparable to a stand-alone aggregometer, although CS-2000i has the advantages of walk-away technology and also required a smaller sample volume than the AggRAM (44% less). PMID:24237750

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

    PubMed

    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 (p<0.001) decrement of donor blood counts has been observed after WB donation. Mean donor Hb and platelets reduced by 0.72 g/dl and 22.1 × 10(6)/ml respectively. Quality of RDPs in terms of platelet yield was significantly better (p<0.001) when donor platelet 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

  14. Platelet counts, MPV and PDW in culture proven and probable neonatal sepsis and association of platelet counts with mortality rate.

    PubMed

    Ahmad, Mirza Sultan; Waheed, Abdul

    2014-05-01

    To determine frequency of thrombocytopenia and thrombocytosis, the MPV (mean platelet volume) and PDW (platelet distribution width) in patients with probable and culture proven neonatal sepsis and determine any association between platelet counts and mortality rate. Descriptive analytical study. NICU, Fazle Omar Hospital, from January 2011 to December 2012. Cases of culture proven and probable neonatal sepsis, admitted in Fazle Omar Hospital, Rabwah, were included in the study. Platelet counts, MPV and PDW of the cases were recorded. Mortality was documented. Frequencies of thrombocytopenia (< 150000/mm3) and thrombocytosis (> 450000/mm3) were ascertained. Mortality rates in different groups according to platelet counts were calculated and compared by chi-square test to check association. Four hundred and sixty nine patients were included; 68 (14.5%) of them died. One hundred and thirty six (29%) had culture proven sepsis, and 333 (71%) were categorized as probable sepsis. Thrombocytopenia was present in 116 (24.7%), and thrombocytosis was present in 36 (7.7%) cases. Median platelet count was 213.0/mm3. Twenty eight (27.7%) patients with thrombocytopenia, and 40 (12.1%) cases with normal or raised platelet counts died (p < 0.001). Median MPV was 9.30, and median PDW was 12.30. MPV and PDW of the patients who died and who were discharged were not significantly different from each other. Thrombocytopenia is a common complication of neonatal sepsis. Those with thrombocytopenia have higher mortality rate. No significant difference was present between PDW and MPV of the cases who survived and died.

  15. Automated platelet aggregation analysis using a digitizer.

    PubMed

    Kohler, C A; Zoltan, B J

    1984-09-01

    A method of rapidly entering, reducing, and interpreting data collected in platelet aggregation studies has been developed. The standard aggregometer output is a chart recording of light transmittance (or optical density) as a function of time following the addition of an aggregating agent to a cuvette containing platelet-rich plasma or washed, suspended platelets. Two problems associated with aggregation studies are the proper calibration of the aggregometer and recorder to insure that comparisons of data can be made from experiment to experiment and the need to find a convenient way to analyze and summarize the data generated. In this method, the chart recorder is calibrated using reference cuvettes containing water or a suspension of latex beads of a known optical density. Since the analysis and interpretation of aggregation curves can be a time-consuming task, a standard digitizer has been interfaced to a computer, allowing the X,Y coordinates of the data, and, thus, the time-aggregation history of the sample, to be entered into the computer. The cursor of the digitizer is traced over the aggregation curve and the X,Y coordinates are transferred either at operator-selectable points or at fixed time intervals. A computer program (AGGPAD) calculates and stores several variables (e.g., sample baseline density, the magnitude of the aggregation, time to peak aggregation, maximum aggregation rate, and maximum deaggregation rate) that can be easily retrieved. The system reduces analysis time by a factor of five and allows for automated data storage and retrieval. The method is applicable to any computer and hardware costs are below $1000.00.

  16. 21 CFR 864.5700 - Automated platelet aggregation system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated platelet aggregation system. 864.5700 Section 864.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology...

  17. 21 CFR 864.5700 - Automated platelet aggregation system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated platelet aggregation system. 864.5700 Section 864.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  18. 21 CFR 864.5700 - Automated platelet aggregation system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated platelet aggregation system. 864.5700 Section 864.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  19. 21 CFR 864.5700 - Automated platelet aggregation system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated platelet aggregation system. 864.5700 Section 864.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  20. 21 CFR 864.5700 - Automated platelet aggregation system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated platelet aggregation system. 864.5700 Section 864.5700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  1. 21 CFR 864.8175 - Calibrator for platelet counting.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calibrator for platelet counting. 864.8175 Section 864.8175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8175 Calibrator...

  2. 21 CFR 864.8175 - Calibrator for platelet counting.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calibrator for platelet counting. 864.8175 Section 864.8175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8175 Calibrator for...

  3. 21 CFR 864.8175 - Calibrator for platelet counting.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calibrator for platelet counting. 864.8175 Section 864.8175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8175 Calibrator for...

  4. 21 CFR 864.8175 - Calibrator for platelet counting.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calibrator for platelet counting. 864.8175 Section 864.8175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8175 Calibrator for...

  5. 21 CFR 864.8175 - Calibrator for platelet counting.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calibrator for platelet counting. 864.8175 Section 864.8175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8175 Calibrator for...

  6. Prognostic significance of platelet count in SLE patients.

    PubMed

    Abdel Galil, Sahar Mahfouz; Edrees, Azzahra Mohammed; Ajeeb, Afnan Khaled; Aldoobi, Ghadeer Sameer; El-Boshy, Mohamed; Hussain, Waleed

    2017-03-01

    Hematological abnormalities, especially thrombocytopenia (TCP), are highly prevalent among patients with systemic lupus erythematosus (SLE) and at the same time it has been reported as a significant prognostic factor of SLE course. We further investigate the correlation between platelet count and the clinical manifestations and disease activity of SLE, in a cohort of Saudi Arabian female patients. A retrospective analysis was done for the medical records of 100 SLE female patients, selected from all patients diagnosed and treated for SLE at the Rheumatology outpatient clinics in Hera'a General Hospital, Holly Makkah, Saudi Arabia. The data collected from every patient's file included laboratory investigations (complete blood count, platelet parameters, ESR, anti-double-stranded DNA antibody, ANA), clinical manifestations, as well as SLE disease activity index (SLEDAI-2k) scores throughout a period of six sequential follow-up visits. Patients were divided into three groups according to the SLEDAI-2k: mild, moderate, and high-activity group. We found that, out of 100 patients, TCP was the most prevalent hematological abnormality evident in 15%, more than leucopenia (14%) and anemia (2%). TCP was acute in onset and associated with arthritis, neurologic manifestations, and nephritis. Platelet count showed a significant negative correlation with disease activity, in all of the three groups of patients. We concluded that platelet count has a negative correlation with disease activity in SLE patients, whatever the associated manifestations, and it should be considered as a prognostic factor, identifying patients with aggressive disease course.

  7. Platelet count kinetics following interruption of antiretroviral treatment.

    PubMed

    Zetterberg, Eva; Neuhaus, Jacqueline; Baker, Jason V; Somboonwit, Charurut; Llibre, Josep M; Palfreeman, Adrian; Chini, Maria; Lundgren, Jens D

    2013-01-02

    To investigate the mechanisms of platelet kinetics in the Strategies for Management of Antiretroviral Therapy (SMART) study that demonstrated excess mortality with CD4 guided episodic antiretroviral therapy (ART) drug conservation compared with continuous treatment viral suppression. Follow-up analyses of stored plasma samples demonstrated increased activation of both inflammatory and coagulation pathways after stopping ART. SMART patients from sites that determined platelets routinely. Platelet counts were retrospectively collected from 2206 patients from visits at study entry, and during follow-up. D-dimer levels were measured at study entry, month 1, and 2. Platelet levels decreased in the drug conservation group following randomization, but remained stable in the viral suppression group [median (IQR) decline from study entry to month 4: -24 000/μl (-54 000 to 4000) vs. 3000 (-22 000 to 24 000), respectively, P < 0.0001)] and the rate of developing thrombocytopenia (<100 000/μl) was significantly higher in the drug conservation vs. the viral suppression arm (unadjusted drug conservation/viral suppression [HR (95%CI) = 1.8 (1.2-2.7)]. The decline in platelet count among drug conservation participants on fully suppressive ART correlated with the rise in D-dimer from study entry to either month 1 or 2 (r = -0.41; P = 0.02). Among drug conservation participants who resumed ART 74% recovered to their study entry platelet levels. Interrupting ART increases the risk of thrombocytopenia, but reinitiation of ART typically reverses it. Factors contributing to declines in platelets after interrupting ART may include activation of coagulation pathways or HIV-1 replication itself. The contribution of platelets in HIV-related procoagulant activity requires further study.

  8. Platelet count kinetics following interruption of antiretroviral treatment

    PubMed Central

    Zetterberg, Eva; Neuhaus, Jacqueline; Baker, Jason V.; Somboonwit, Charurut; Llibre, Josep M.; Palfreeman, Adrian; Chini, Maria; Lundgren, Jens D.

    2014-01-01

    Objectives To investigate the mechanisms of platelet kinetics in the Strategies for Management of Antiretroviral Therapy (SMART) study that demonstrated excess mortality with CD4 guided episodic antiretroviral therapy (ART) drug conservation compared with continuous treatment viral suppression. Follow-up analyses of stored plasma samples demonstrated increased activation of both inflammatory and coagulation pathways after stopping ART. Design SMART patients from sites that determined platelets routinely. Methods Platelet counts were retrospectively collected from 2206 patients from visits at study entry, and during follow-up. D-dimer levels were measured at study entry, month 1, and 2. Results Platelet levels decreased in the drug conservation group following randomization, but remained stable in the viral suppression group [median (IQR) decline from study entry to month 4: −24 000/µl (−54 000 to 4000) vs. 3000 (−22 000 to 24 000), respectively, P < 0.0001)] and the rate of developing thrombocytopenia (<100 000/µl) was significantly higher in the drug conservation vs. the viral suppression arm (unadjusted drug conservation/viral suppression [HR (95%CI) = 1.8 (1.2–2.7)]. The decline in platelet count among drug conservation participants on fully suppressive ART correlated with the rise in D-dimer from study entry to either month 1 or 2 (r = −0.41; P = 0.02). Among drug conservation participants who resumed ART 74% recovered to their study entry platelet levels. Conclusion Interrupting ART increases the risk of thrombocytopenia, but reinitiation of ART typically reverses it. Factors contributing to declines in platelets after interrupting ART may include activation of coagulation pathways or HIV-1 replication itself. The contribution of platelets in HIV-related procoagulant activity requires further study. PMID:23018440

  9. Platelet count on slow induction to high altitude

    NASA Astrophysics Data System (ADS)

    Sharma, Subhash C.

    1986-03-01

    Platelet counts were estimated at sea level in 50 lowlanders. They were divided at random in two groups (A and B) of 25 each. Group A went up by train/road transport to 3658 m, while group B reached the same height after 8 days of acclimatisation enroute. Platelet counts were estimated serially in both groups at high altitude. Symptoms of high altitude exposure were also recorded. No significant change in the counts was noted in either group and none became “Symptomatic”. All were brought back to sea level by air and deinduction studies carried out on days 1 and 4 of return. The importance of these findings in the light of our existing knowledge is discussed.

  10. The influence of bromelain on platelet count and platelet activity in vitro.

    PubMed

    Gläser, Doreen; Hilberg, Thomas

    2006-02-01

    Bromelain is a general name for a family of sulfhydryl-containing, proteolytic enzymes from the pineapple plant. The aim of the present study was to investigate the influence of bromelain on platelet count, platelet aggregation and platelet activity in vitro. Blood samples were taken from the antecubital vein of 10 healthy male non-smokers. Platelet count decreased after incubation with 2.5 and 5 mg bromelain/ml from 277 +/- 17 platelets/nl before to 256 +/- 21 and 247 +/- 19 platelets/nl after the treatment. The ADP and TRAP-6 induced platelet aggregation led to a significant decrease after the incubation with 2.5 mg (ADP: 48.6 +/- 25.7%; TRAP-6: 49.6 +/- 28.9%) or 5 mg (ADP: 5.0 +/- 4.6%; TRAP-6: 9.0 +/- 4.9%) bromelain/ml in comparison to control (ADP: 81.4 +/- 5.0%; TRAP-6: 77.4 +/- 10.4%). The percentage of unstimulated CD62P positive platelets which were investigated by flow cytometry was minimally higher after incubation with 5 mg bromelain/ml (0.57 +/- 0.48% PC) in comparison to control (0.22 +/- 0.11% PC), but after TRAP-6 stimulation the incubation with 5 mg bromelain/ml led to a remarkable decrease in comparison to the untreated control (50.4 +/- 20.2 to 0.9 +/- 0.8% PC). The changes of CD62P (TRAP-stimulated) and the results of platelet aggregation after incubation with bromelain in vitro may demonstrate the potential of bromelain as a substance for platelet inhibition.

  11. The role of platelet count, mean platelet volume, and the mean platelet volume/platelet count ratio in predicting postoperative vomiting in children after deep sedation

    PubMed Central

    Canpolat, Dilek G.; Dogruel, Fatma; Gönen, Zeynep B.; Yılmaz, Canay; Zararsız, Gökmen; Alkan, Alper

    2016-01-01

    Objectives: To determine the role of hemogram parameters such as platelet count (PLT), mean platelet volume (MPV), and the MPV/PLT ratio in predicting the risk of postoperative vomiting (POV) in children after tooth extraction under deep sedation. Methods: A total of 100 American Society of Anesthesiology Classification I and II pediatric patients who underwent tooth extraction procedures under a standard anesthetic method were included in the study between 2012 and 2014. The study took place at the Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Erciyes University, Erciyes, Turkey Fifty patients without POV (group 1) and 50 patients with POV (group 2) were retrospectively selected randomly from the records of 885 consecutive patients. Age, gender, duration of the operation, and preoperative hemogram findings were recorded. Results: There was a statistically significant difference between the 2 groups in terms of MPV (p<0.001), PLT (p=0.006), and MPV/PLT (p<0.001) ratio. Mean platelet volume and MPV/PLT ratio were higher in group 2, whereas PLT was higher in group 1. Conclusion: The PLT count, MPV, and MPV/PLT ratio may be used to predict POV in children. PMID:27652358

  12. Reticulated platelet levels in whole blood and platelet-rich plasma of dogs with various platelet counts measured by flow cytometry.

    PubMed

    Maruyama, Haruhiko; Yamagami, Hirozumi; Watari, Toshihiro; Kano, Rui; Fujino, Yasuhito; Tsujimoto, Hajime; Hasegawa, Atsuhiko; Kamata, Hiroshi

    2009-02-01

    Reticulated platelets (RP) are young platelets that contain residual RNA, and measurement of RP has been to assess thrombopoiesis. In the present study, flow cytometric counts of RP were compared using paired specimens elicited from dogs with various platelet counts by different RP collection procedures, the whole blood method (WBM) and platelet rich plasma method (PRPM). The flow cytometric counts of RP for the specimens collected by WBM showed good and stable agreement with those taken by PRPM from the same canine subjects. The result revealed that WBM, as well as PRPM, can be used clinically to determine RP levels in dogs with abnormal platelet counts.

  13. Platelet count and outcome in patients with acute venous thromboembolism.

    PubMed

    Di Micco, Pierpaolo; Ruiz-Giménez, Nuria; Nieto, José Antonio; Aujesky, Drahomir; del Molino, Fátima; Valle, Reina; Barrón, Manuel; Maestre, Ana; Monreal, Manuel

    2013-11-01

    The relationship between platelet count and outcome in patients with acute venous thromboembolism (VTE) has not been consistently explored. RIETE is an ongoing registry of consecutive patients with acute VTE. We categorised patients as having very low- (<80,000/µl), low- (80,000/µl to 150,000/µl), normal- (150,000/µl to 300,000/µl), high- (300,000/µl to 450,000/µl), or very high (>450,000/µl) platelet count at baseline, and compared their three-month outcome. As of October 2012, 43,078 patients had been enrolled in RIETE: 21,319 presenting with pulmonary embolism and 21,759 with deep-vein thrombosis. In all, 502 patients (1.2%) had very low-; 5,472 (13%) low-; 28,386 (66%) normal-; 7,157 (17%) high-; and 1,561 (3.6%) very high platelet count. During the three-month study period, the recurrence rate was: 2.8%, 2.2%, 1.8%, 2.1% and 2.2%, respectively; the rate of major bleeding: 5.8%, 2.6%, 1.7%, 2.3% and 4.6%, respectively; the rate of fatal bleeding: 2.0%, 0.9%, 0.3%, 0.5% and 1.2%, respectively; and the mortality rate: 29%, 11%, 6.5%, 8.8% and 14%, respectively. On multivariate analysis, patients with very low-, low-, high- or very high platelet count had an increased risk for major bleeding (odds ratio [OR]: 2.70, 95% confidence interval [CI]: 1.85-3.95; 1.43 [1.18-1.72]; 1.23 [1.03-1.47]; and 2.13 [1.65-2.75]) and fatal bleeding (OR: 3.70 [1.92-7.16], 2.10 [1.48-2.97], 1.29 [0.88-1.90] and 2.49 [1.49-4.15]) compared with those with normal count. In conclusion, we found a U-shaped relationship between platelet count and the three-month rate of major bleeding and fatal bleeding in patients with VTE.

  14. The Impact of Apheresis Platelet Manipulation on Corrected Count Increment

    PubMed Central

    Karafin, Matthew; Fuller, Alice K.; Savage, William J.; King, Karen E.; Ness, Paul M; Tobian, Aaron A. R.

    2012-01-01

    Background Concentrating and washing apheresis platelets (APs) substantially reduce the number of allergic transfusion reactions likely due to removal of plasma. However, these processes may damage platelets. This study evaluated whether concentrating or washing APs decrease the Corrected Count Increment (CCI). Study Design and Methods This retrospective study evaluated individuals who initially received unmanipulated APs and subsequently received concentrated and/or washed APs at a large university hospital between 1998 and 2009. Concentrated units were prepared by reducing the plasma volume of APs by a goal of >67%. Washed units were prepared by washing the APs with 1L normal saline. The CCI (plt × m2/uL) for all transfusions was calculated. Hypothesis testing was performed with Student’s t-tests for continuous variables and chi-square tests for dichotomous variables. Results We evaluated 121 individuals; 46 patients who received unmanipulated, concentrated and then washed APs, 59 patients who received unmanipulated and then concentrated APs; and 16 patients who received unmanipulated and then washed APs. Patient demographics were similar among the three groups. The mean CCI for unmanipulated AP transfusions at 0–2 hours post transfusion were significantly higher than concentrated and washed platelet transfusions (p<0.001). However, when accounting for platelet loss due to manipulation, concentrating APs did not impact the CCI, but the CCI remained significantly lower for washed products at all time points post transfusion (40.7% mean reduction at 20–24 hours, p<0.001). Conclusions Washing APs significantly reduces platelet count recovery and survival, as demonstrated by a significantly reduced CCI. PMID:22233358

  15. Functional platelet defects in children with severe chronic ITP as tested with 2 novel assays applicable for low platelet counts.

    PubMed

    van Bladel, Esther R; Laarhoven, Annemieke G; van der Heijden, Laila B; Heitink-Pollé, Katja M; Porcelijn, Leendert; van der Schoot, C Ellen; de Haas, Masja; Roest, Mark; Vidarsson, Gestur; de Groot, Philip G; Bruin, Marrie C A

    2014-03-06

    Immune thrombocytopenia (ITP) is an autoimmune disease with a complex heterogeneous pathogenesis and a bleeding phenotype that is not necessarily correlated to platelet count. In this study, the platelet function was assessed in a well-defined cohort of 33 pediatric chronic ITP patients. Because regular platelet function test cannot be performed in patients with low platelet counts, 2 new assays were developed to determine platelet function: first, the microaggregation test, measuring in platelets isolated from 10 mL of whole blood the platelet potential to form microaggregates in response to an agonist; second, the platelet reactivity assay, measuring platelet reactivity to adenosine diphosphate (ADP), convulxin (CVX), and thrombin receptor activator peptide in only 150 μL of unprocessed whole blood. Patients with a severe bleeding phenotype demonstrated a decreased aggregation potential upon phorbol myristate acetate stimulation, decreased platelet degranulation following ADP stimulation, and a higher concentration of ADP and CVX needed to activate the glycoprotein IIbIIIa complex compared with patients with a mild bleeding phenotype. In conclusion, here we have established 2 functional tests that allow for evaluation of platelet function in patients with extremely low platelet counts (<10(9)). These tests show that platelet function is related to bleeding phenotype in chronic ITP.

  16. Two cases of false platelet clumps flagged by the automated hematology analyzer Sysmex XE-2100.

    PubMed

    Dai, Qingkai; Zhang, Ge; Lai, Chunqi; Du, Zeli; Chen, Lan; Chen, Qi; Peng, Leiwen; Wang, Yuefang; Yang, Hui; Ye, Lei; Yang, Xianjun; Jiang, Yongmei

    2014-02-15

    Automated hematology analyzer is widely used by clinical laboratories to examine blood cell counts and differential leukocyte counts. However, a microscopic examination of a well-prepared blood film is still necessary and useful in most cases. Two patients with severe disease were required complete blood counts (CBC) after admission at West China Second University Hospital in Southwest China. A false "platelet clumps?" flag was generated by the automated hematology analyzer Sysmex XE-2100. However, when the well-prepared blood film was reviewed, there was echinocytosis rather than clumps of platelets. In addition, both patients had severe metabolic acidosis with arterial blood pH <7.00 and HCO3- <4 mmol/l. On day 2 of admission, the false platelet clumps flags were not presented in both cases. Our further results suggested that the false platelet clumps had been flagged probably due to the influence of the extremely low blood pH. These two cases emphasized that a microscopic examination of a blood film was central to the morphology of blood cells. When the result of microscopic examination was abnormal, it was suggested that the physician should consider further testing to find underlying condition. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    PubMed Central

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

    2014-01-01

    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. PMID:24755410

  18. Platelet Activation and Platelet-Monocyte Aggregate Formation Contribute to Decreased Platelet Count During Acute Simian Immunodeficiency Virus Infection in Pig-tailed Macaques

    PubMed Central

    Metcalf Pate, Kelly A.; Lyons, Claire E.; Dorsey, Jamie L.; Shirk, Erin N.; Queen, Suzanne E.; Adams, Robert J.; Gama, Lucio; Morrell, Craig N.; Mankowski, Joseph L.

    2013-01-01

    Platelets are key participants in innate immune responses to pathogens. As a decrease in circulating platelet count is one of the initial hematologic indicators of human immunodeficiency virus (HIV) infection, we sought to determine whether decline in platelet number during acute infection results from decreased production, increased antibody-mediated destruction, or increased platelet activation in a simian immunodeficiency virus (SIV)/macaque model. During acute SIV infection, circulating platelets were activated with increased surface expression of P-selectin, CD40L and major histocompatibility complex class I. Platelet production was maintained and platelet autoantibodies were not detected during acute infection. Concurrent with a decrease in platelet numbers and an increase in circulating monocytes, platelets were found sequestered in platelet-monocyte aggregates, thereby contributing to the decline in platelet counts. Because the majority of circulating CD16+ monocytes formed complexes with platelets during acute SIV infection, a decreased platelet count may represent platelet participation in the innate immune response to HIV. PMID:23852120

  19. Effects of biological variations on platelet count in healthy subjects in China.

    PubMed

    Peng, Liming; Yang, Jing; Lu, Xiaojun; Okada, Tokuhiro; Kondo, Tamiaki; Ruan, Changgeng; Wu, Yun; Xin, Xiaomin

    2004-02-01

    The effects of biological variations on platelet counts were investigated in 694 healthy subjects aged 18 to 60 years living in three cities including Chengdu (Sichuan Province), Suzhou (Jiangsu Province) and Harbin (Heilongjang Province) in China. Platelet counts in healthy subjects were significantly lower in Chengdu (52-202 x 10(9)/L) and Suzhou (60-259 x 10(9)/L) than in Harbin (154-348 x 10(9)/L) (p <0.0001), but the mean platelet volume (MPV) determined concurrently was negatively correlated with platelet count, the MPV values were significantly higher in Chengdu (11.8-15.6 fl) and Suzhou (10.9-15.8 fl) than in Harbin (9.5 approximately 12.9 fl) (p < 0.0001). Platelet counts were significantly higher in summer (73-289 x 10(9)/L) than in winter (52-202 x 10(9)/L) (p <0.0001), but the MPV values were lower in summer (11.2-14.7 fl) than in winter (11.8-15.6 fl) (p <0.05) in Chengdu. Platelet associated immunoglobulin (PA-IgG) in Chengdu was revealed to be significantly higher in the low platelet count group (<150 x 10(9)/L, 13.5 +/- 7.1 ng/10(7) PLT) than in the normal platelet count group (> or =150 x 10(9)/L, 8.3 +/- 2.7 ng/10(7) PLT) (p <0.0001). Similar results were observed in Suzhou for the reticulated platelet ratio, which was significantly higher in the low platelet count group (19.5 +/- 7.1%) than in the normal platelet count group (11.6 +/- 2.7%) (p <0.01). The bleeding time in Chengdu showed a significantly longer time in the low platelet count group (8.6 +/- 2.3 min) than in the normal platelet count group (6.0 +/- 1.2 min)(p <0.01). With regard to the effects of lipids on platelet counts, the HDL values were significantly higher in the normal platelet count group (1.60 +/- 0.76 mmol/L) than the low platelet count group (1.23 +/- 0.31 mmol/L) (p <0.01); but no significant differences in cholesterol and triglycerides values between the normal and low platelet count groups (p >0.05) were recorded. These findings suggest that the platelet counts could

  20. A new one-platform flow cytometric method for residual cell counting in platelet concentrates.

    PubMed

    Schmidt, Michael; Spengler, Hans-Peter; Lambrecht, Bernd; Hourfar, Michael K; Seifried, Erhard; Tonn, Torsten

    2009-12-01

    According to German regulations and guidelines, residual red blood cells (rRBCs) and residual white blood cells (rWBCs) must number fewer than 3 x 10(9) cells/unit and 1 x 10(6) cells/unit in platelet concentrates (PCs), respectively. Due to low levels of residual cells in final products, there is still a need for fast, reliable, and sensitive methods of automated detection of these cell types. In Part A, 21 PCs were spiked with predetermined numbers of red blood cells (RBCs) and white blood cells (WBCs). The linearity, precision, and accuracy of the BD Thrombo Count assay (BD Biosciences Europe) were tested and validated according to international guidelines. Finally in Part B, 100 PCs prepared from pooled buffy coats were tested by the BD Thrombo Count assay and compared with other methods, including Nageotte (rWBCs) and Neubauer (rRBCs) counting chambers and the flow cytometric BD LeucoCOUNT (Becton Dickinson) assay (rWBCs). The unspecific background of blank PC samples was fewer than 0.02 cells/microL for WBCs and fewer than 34 cells/microL for RBCs (mean, 21). Linear regression and precision analyses of spiked PC samples were determined for both WBCs (r(2) = 0.992; range, 0.6-6.0 WBCs/microL) and RBCs (r(2) = 0.999; 800-8000 RBCs/microL). No carryover of cells or drift in results was detected in the automated sample acquisition mode. Analysis according to statistical methods of Bland and Altman demonstrated a high correlation between BD Thrombo Count and the Neubauer manual counting chamber. This novel flow cytometric test is a quick and reliable single-tube assay that has been demonstrated as a potential alternative for the existing manual microscopic counting procedures that are both time-consuming and laborious.

  1. A side-by-side evaluation of four platelet-counting instruments.

    PubMed

    Dalton, W T; Bollinger, P; Drewinko, B

    1980-08-01

    The performances of four instruments for counting platelets were evaluated in a side-by-side study: the Haema-Count MK-4/HC, an electronic impedance instrument that counts platelets in platelet-rich plasma; the Ultra-Flo 100, and the Coulter Counter Model S-Plus, electronic impedance instruments that count platelets in the presence of intact erythrocytes; and the AutoCounter, an optical instrument that counts platelets in the presence of lysed erythrocytes. The Ultra-Flo 100 and the S-Plus showed the best within-run precision, and all four instruments were considerably more precise than manual platelet counting, especially at low levels of platelet count. The four instruments were all linear in the ranges tested (5 to 650 x 10(9)/or greater), and sample carry-over was less than 0.7% for each. A noteworthy finding was that the erythrocyte concentration of the blood samples affected the displayed platelet count of the S-Plus and, to a lesser extent, that of the AutoCounter, in a predictable way, whereas it did not greatly affect the displayed count of the Ultra-Flo 100. In addition to differences in quality of performances, the four instruments differed considerably in speed and ease of operation and in cost.

  2. An Increase in Mean Platelet Volume/Platelet Count Ratio Is Associated with Vascular Access Failure in Hemodialysis Patients

    PubMed Central

    Shin, Dong Ho; Rhee, So Yon; Jeon, Hee Jung; Park, Ji-Young; Kang, Shin-Wook; Oh, Jieun

    2017-01-01

    After stenosis of arteriovenous vascular access in hemodialysis patients, platelets play a crucial role in subsequent thrombus formation, leading to access failure. In a previous study, the mean platelet volume (MPV)/platelet count ratio, but not MPV alone, was shown to be an independent predictor of 4-year mortality after myocardial infarction. However, little is known about the potential influence of MPV/platelet count ratio on vascular access patency in hemodialysis patients. A total of 143 patients undergoing routine hemodialysis were recruited between January 2013 and February 2016. Vascular access failure (VAF) was defined as thrombosis or a decrease of greater than 50% of normal vessel diameter, requiring either surgical revision or percutaneous transluminal angioplasty. Cox proportional hazards model analysis ascertained that the change of MPV/platelet count ratio between baseline and 3 months [Δ(MPV/platelet count ratio)3mo-baseline] had prognostic value for VAF. Additionally, the changes of MPV/platelet count ratio over time were compared in patients with and without VAF by using linear mixed model analysis. Of the 143 patients, 38 (26.6%) were diagnosed with VAF. During a median follow-up of 26.9 months (interquartile range 13.0–36.0 months), Δ(MPV/platelet count ratio)3mo-baseline significantly increased in patients with VAF compared to that in patients without VAF [11.6 (6.3–19.0) vs. 0.8 (-1.8–4.0), P< 0.001]. In multivariate analysis, Δ(MPV/platelet ratio count)3mo-baseline was an independent predictor of VAF, after adjusting for age, sex, diabetes, hypertension, coronary artery disease, cerebrovascular disease, vascular access type, the presence of previous VAF, and antiplatelet drug use (hazard ratio, 1.15; 95% confidence interval, 1.10–1.21; P< 0.001). Moreover, a liner mixed model revealed that there was a significant increase of MPV/platelet count ratio over time in patients with VAF compared to those without VAF (P< 0.001). An

  3. A Meta-Analysis and Genome-Wide Association Study of Platelet Count and Mean Platelet Volume in African Americans

    PubMed Central

    Qayyum, Rehan; Snively, Beverly M.; Ziv, Elad; Nalls, Michael A.; Liu, Yongmei; Tang, Weihong; Yanek, Lisa R.; Lange, Leslie; Evans, Michele K.; Ganesh, Santhi; Austin, Melissa A.; Lettre, Guillaume; Becker, Diane M.; Zonderman, Alan B.; Singleton, Andrew B.; Harris, Tamara B.; Mohler, Emile R.; Logsdon, Benjamin A.; Kooperberg, Charles; Folsom, Aaron R.; Wilson, James G.

    2012-01-01

    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

  4. Counting platelets in platelet concentrates on hematology analyzers: a multicenter comparative study.

    PubMed

    van der Meer, Pieter F; Dijkstra-Tiekstra, Margriet J; Mahon, Anne; de Wildt-Eggen, Janny

    2009-01-01

    Hematology analyzers are designed to count whole blood samples, but are also used by blood centers to perform quality control on blood components. In platelet (PLT) concentrates, the number of PLTs is approximately fivefold higher and red blood cells are absent, causing variable PLT counting results. It was our aim to compare currently used hematology analyzers for counting PLTs in PLT concentrates using fixed human PLTs. PLT samples were fixed, diluted into seven concentration levels (plus one blank), aliquoted, and shipped to 68 centers. Evaluable data were obtained for 89 hematology analyzers. All samples were counted six times, and results were reported to the coordinating center. The overall group mean was calculated, and the percentage deviation from this mean was calculated for each analyzer. At PLT levels relevant for blood centers, 750 x 10(9) to 2000 x 10(9) per L, analyzers gave results that were between 35 percent lower and 16 percent higher than the overall group mean. Within a group of analyzers, results were comparable with coefficient of variations usually below 10 percent, indicating that the observed differences were caused by instrument characteristics. A smaller study with fresh, unfixed PLT samples showed that analyzers behaved similarly for fixed and fresh PLTs. With a wide array of currently used hematology analyzers, a marked difference was determined for the PLT counts of fixed human-based identical samples provided to 68 laboratories by a centralized facility. A gold standard method is needed to allow for more valid interlaboratory comparisons between hematology analyzers.

  5. Correlation study between platelet count, leukocyte count, nonhemorrhagic complications, and duration of hospital stay in dengue fever with thrombocytopenia

    PubMed Central

    Jayanthi, Hari Kishan; Tulasi, Sai Krishna

    2016-01-01

    Introduction: Dengue is one of the common diseases presenting as fever with thrombocytopenia, also causing significant morbidity and complications. Objectives: Though the correlation between platelet count, bleeding manifestations and hemorrhagic complications has been extensively studied, less is known about the correlation between platelet count and non hemorrhagic complications. This study was done to see the correlation between platelet count and non hemorrhagic complications, duration of hospital stay and additive effect of leucopenia with thrombocytopenia on complications. Methods: Our study is prospective observational study done on 99 patients who had dengue fever with thrombocytopenia. Correlations were obtained using scatter plot and SPSS software trail version. Results: Transaminitis (12.12%) was the most common complication followed by acute renal injury (2%). In our study we found that, as the platelet count decreased the complication rate increased (P = 0.0006). In our study duration of hospital increased (P is 0.00597) with decreasing platelet count when compared to other study where there was no correlation between the two. There was no correlation between thrombocytopenia with leucopenia and complications (P is 0.292), similar to other study. Conclusion: Platelet count can be used to predict the complication and duration of hospital stay and hence better use of resources. PMID:27453855

  6. Cardiovascular correlates of platelet count and volume in the Framingham Heart Study

    PubMed Central

    Sloan, Arielle; Gona, Philimon; Johnson, Andrew

    2015-01-01

    Purpose Platelet count and volume are inexpensive, routinely-assayed biomarkers associated with cardiovascular health, but specific relationships among platelet indices, cardiovascular risk factors, and disease warrant further investigation. The purpose of this study was to understand associations among platelet count, volume, and 20 cardiovascular health-related variables in the Framingham Heart Study. Methods Cross-sectional analyses were performed on platelet count and volume associations with cardiovascular health indicators in three Framingham Heart Study cohorts (Original n=964, Offspring n=2,699, and Third Generation n=2,419) using multivariable linear regression analysis. Time-to-event analysis was employed for cardiovascular disease-related event incidences using Kaplan-Meier plots and Cox proportional hazards regression adjusted for age and gender. Results Results were concordant with the hypothesis that higher platelet counts are associated with less favorable cardiovascular risk profiles, although mean platelet volume associations were weaker. In our analysis, increased platelet count across FHS cohorts was consistently associated with smoking, triglycerides, LDL and total cholesterol levels. Some associations with platelet count appeared gender-dependent. Conclusions Significant associations of common blood platelet measurements are observed with gender and cardiovascular risk factors, namely smoking and lipids. Research is warranted to confirm these relationships in other cohorts, evaluate differences by ethnicity and examine longitudinal effects on disease risk. PMID:25771288

  7. The prognostic value of pretreatment platelet count in patients with head and neck squamous cell carcinoma.

    PubMed

    Pardo, Laura; Valero, Cristina; López, Montserrat; García, Jacinto; Camacho, Mercedes; Quer, Miquel; León, Xavier

    2017-06-01

    Thrombocytosis is commonly observed in patients with solid tumors. This study aimed to evaluate the prognostic role of circulating pretreatment platelet count in a large series of patients with head and neck squamous cell carcinoma (HNSCC). We retrospectively studied 824 patients with HNSCC treated at a single institution from 2000 to 2012. Disease-specific survival and local, regional, and distant recurrence-free survival were analyzed according to the distribution of the platelet count. By defining the platelet count 250.05×10(9)/L as a cut-off point with the best predictive capacity, we classified the patients into two groups: those with a high platelet count (n=378, 45.9%), and those with a low platelet count (n=446, 54.1%). On univariate analysis, there were significant differences in disease-specific survival depending on pretreatment platelet count (P=0.001). The 5-year specific survival rates were 74.1% (CI 95%: 69.8-78.4%) and 61.6% (CI 95%: 56.4-66.8%) for patients with a low and high platelet count, respectively. According to the results of a multivariate analysis, patients with a high count of platelets had a tendency to a lower disease-specific survival, but the hazard ratio did not reach statistically significant differences (HR 1.24, CI 95%: 0.97-1.61, P=0.085). Platelet count was significantly associated with survival in univariate analysis. However, in a multivariate analysis it lost its prognostic capacity, limiting its utility as a prognostic marker in patients with HNSCC. Considering separately each primary tumor location, patients with hypopharyngeal cancer and a high platelet count had a significant decrease of disease-specific survival. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Determinants of platelet count in pediatric patients with congenital cyanotic heart disease: Role of immature platelet fraction.

    PubMed

    Matter, Randa M; Ragab, Iman A; Roushdy, Alaa M; Ahmed, Ahmed G; Aly, Hanan H; Ismail, Eman A

    2017-09-07

    Congenital heart defects are common noninfectious causes of mortality in children. Bleeding and thrombosis are both limiting factors in the management of such patients. We assessed the frequency of thrombocytopenia in pediatric patients with congenital cyanotic heart disease (CCHD) and evaluated determinants of platelet count including immature platelet fraction (IPF) and their role in the pathogenesis of thrombocytopenia. Forty-six children and adolescents with CCHD during pre-catheter visits were studied; median age was 20.5 months. Complete blood count including IPF as a marker of platelet production and reticulated hemoglobin content (RET-He) as a marker of red cell production and iron status were done on Sysmex XE 2100 (Sysmex, Japan). C-reactive protein, prothrombin time (PT), Activated partial thromboplastin time (APTT) were also assessed. Thrombocytopenia was found in 6 patients (13%). PT was prolonged (P = .016) and IPF was significantly higher in patients with thrombocytopenia compared with patients with normal platelet count (14.15 ± 5.2% vs 6.68 ± 3.39%; P = .003). Platelet count was negatively correlated with IPF while significant positive correlations were found between IPF and hemoglobin, red blood cells (RBCs) count, hematocrit (Hct), PT, reticulocytes count, and immature reticulocyte fraction. We suggest that elevated IPF in CCHD patients with thrombocytopenia may denote peripheral platelets destruction as an underlying mechanism. Hemoglobin level, RBCs count, Hct, and RET-He were not significant determinants for platelet count in CCHD. © 2017 Wiley Periodicals, Inc.

  9. Red Blood Cell Count Automation Using Microscopic Hyperspectral Imaging Technology.

    PubMed

    Li, Qingli; Zhou, Mei; Liu, Hongying; Wang, Yiting; Guo, Fangmin

    2015-12-01

    Red blood cell counts have been proven to be one of the most frequently performed blood tests and are valuable for early diagnosis of some diseases. This paper describes an automated red blood cell counting method based on microscopic hyperspectral imaging technology. Unlike the light microscopy-based red blood count methods, a combined spatial and spectral algorithm is proposed to identify red blood cells by integrating active contour models and automated two-dimensional k-means with spectral angle mapper algorithm. Experimental results show that the proposed algorithm has better performance than spatial based algorithm because the new algorithm can jointly use the spatial and spectral information of blood cells.

  10. High platelet counts increase metastatic risk in huge hepatocellular carcinoma undergoing transarterial chemoembolization.

    PubMed

    Xue, Tong-Chun; Ge, Ning-Ling; Xu, Xin; Le, Fan; Zhang, Bo-Heng; Wang, Yan-Hong

    2016-09-01

    Accumulating evidence suggests platelets play critical roles in tumor metastasis. Moreover, the role of platelets in metastasis is partially correlated with inflammation. However, evidence regarding the contribution of platelets to hepatocellular carcinoma (HCC) metastasis is lacking. This study investigated the association between platelets and metastatic risk in HCC. We used huge HCC (diameter over 10 cm), a tumor subgroup with a strong inflammatory background, as a model to evaluate the potential predictive role of platelets and platelet-related biomarkers for metastasis in HCC patients undergoing transarterial chemoembolization. A logistic regression model was used to analyze risk factors for metastasis. Patients with huge HCC (n = 178) were enrolled, and 24.7% (44/178) of patients had remote metastases after treatment. Univariate analyses showed high platelet counts (P = 0.012), pretreatment platelet-to-lymphocyte ratios (pre-PLR) of 100 or more (P = 0.018) and post-PLR of 100 or more (P = 0.013) were potential risk factors for metastasis. Furthermore, multivariate analyses showed high platelet counts (odds ratio, 2.18; 95% confidence interval, 1.074-4.443; P = 0.031) and platelet-related biomarkers were independent risk factors for HCC metastasis. Particularly, the risk of metastasis in patients with high post-PLR values was significantly greater than patients with low post-PLR values. For tumor response and survival, patients with high platelet counts had faster disease progression (P = 0.002) and worse survival (P < 0.0001). High platelet counts increase the extrahepatic metastasis risk of huge HCC undergoing chemoembolization, which supply clinical verification of the association between high platelet counts and HCC metastasis. © 2016 The Japan Society of Hepatology.

  11. Trajectory of platelets in pregnancy - do low-risk women need an intrapartum full blood count prior to epidural?

    PubMed

    Duong, Christine; Kidson-Gerber, Giselle; Peters, Nancy; Listijono, Dave R; Henry, Amanda

    2015-10-01

    This study aimed to investigate whether pregnant women with a normal 28-week gestation platelet count and no high-risk conditions for thrombocytopenia require a pre-epidural platelet count. All 1844 included women (platelet count > 150 × 10(9) /L at 28 weeks' gestation, term singleton birth, no thrombocytopenia risk conditions) had a platelet count > 100 × 10(9) /L prebirth, suggesting low-risk pregnant women do not require pre-epidural full blood count solely to check platelet count.

  12. An automated approach for annual layer counting in ice cores

    NASA Astrophysics Data System (ADS)

    Winstrup, M.; Svensson, A. M.; Rasmussen, S. O.; Winther, O.; Steig, E. J.; Axelrod, A. E.

    2012-07-01

    A novel method for automated annual layer counting in seasonally-resolved paleoclimate records has been developed. It relies on algorithms from the statistical framework of Hidden Markov Models (HMMs), which originally was developed for use in machine speech-recognition. The strength of the layer detection algorithm lies in the way it is able to imitate the manual procedures for annual layer counting, while being based on statistical criteria for annual layer identification. The most likely positions of multiple layer boundaries in a section of ice core data are determined simultaneously, and a probabilistic uncertainty estimate of the resulting layer count is provided, ensuring an objective treatment of ambiguous layers in the data. Furthermore, multiple data series can be incorporated and used simultaneously. In this study, the automated layer counting algorithm has been applied to an ice core record from Greenland. The algorithm shows high skill in reproducing the results from manual layer counts.

  13. Automated Counting of Particles To Quantify Cleanliness

    NASA Technical Reports Server (NTRS)

    Rhode, James

    2005-01-01

    A machine vision system, similar to systems used in microbiological laboratories to count cultured microbes, has been proposed for quantifying the cleanliness of nominally precisely cleaned hardware by counting residual contaminant particles. The system would include a microscope equipped with an electronic camera and circuitry to digitize the camera output, a personal computer programmed with machine-vision and interface software, and digital storage media. A filter pad, through which had been aspirated solvent from rinsing the hardware in question, would be placed on the microscope stage. A high-resolution image of the filter pad would be recorded. The computer would analyze the image and present a histogram of sizes of particles on the filter. On the basis of the histogram and a measure of the desired level of cleanliness, the hardware would be accepted or rejected. If the hardware were accepted, the image would be saved, along with other information, as a quality record. If the hardware were rejected, the histogram and ancillary information would be recorded for analysis of trends. The software would perceive particles that are too large or too numerous to meet a specified particle-distribution profile. Anomalous particles or fibrous material would be flagged for inspection.

  14. Validation of three viable-cell counting methods: Manual, semi-automated, and automated.

    PubMed

    Cadena-Herrera, Daniela; Esparza-De Lara, Joshua E; Ramírez-Ibañez, Nancy D; López-Morales, Carlos A; Pérez, Néstor O; Flores-Ortiz, Luis F; Medina-Rivero, Emilio

    2015-09-01

    A viable cell count is essential to evaluate the kinetics of cell growth. Since the hemocytometer was first used for counting blood cells, several variants of the methodology have been developed towards reducing the time of analysis and improving accuracy through automation of both sample preparation and counting. The successful implementation of automated techniques relies in the adjustment of cell staining, image display parameters and cell morphology to obtain equivalent precision, accuracy and linearity with respect to the hemocytometer. In this study we conducted the validation of three trypan blue exclusion-based methods: manual, semi-automated, and fully automated; which were used for the estimation of density and viability of cells employed for the biosynthesis and bioassays of recombinant proteins. Our results showed that the evaluated attributes remained within the same range for the automated methods with respect to the manual, providing an efficient alternative for analyzing a huge number of samples.

  15. Low platelet counts alone do not cause bleeding in an experimental immune thrombocytopenic purpura in mice.

    PubMed

    Domínguez, Victoria; Govezensky, Tzipe; Gevorkian, Goar; Larralde, Carlos

    2003-06-01

    The physiopathogenesis of hemorrhagic phenomena in patients with autoimmune thrombocytopenic purpura is associated with low platelet levels. In the present work the relation between thrombocytopenia and bleeding was examined. The possible participation of endothelial cells in bleeding was also investigated. Immune thrombocytopenia and bleeding were studied in mice injected with anti-mouse and anti-human platelet polyclonal rabbit IgG. Platelet levels were measured at different times and bleeding signs were systematically recorded. ANOVA tests were used to compare platelet levels. Binding of anti-platelet antibodies to vascular endothelial cells was analyzed by immunohistochemistry. Three different doses of anti-platelet IgG caused the same low platelet levels, but bleeding occurred only with high doses of anti-platelet IgG irrespective of the platelet levels. No inflammation around blood vessels was observed in paraffin-embedded tissue sections of organs. Immunohistochemistry demonstrated anti-platelet antibodies bound to vascular endothelium. We showed lack of correlation between platelet counts and bleeding in a murine model. The binding of anti-platelet IgG to endothelial cells of small vessels is an indication that antibody-mediated endothelial activation, in addition to thrombocytopenia, could be participating in bleeding.

  16. Platelet count and transfusion requirements during moderate or severe postpartum haemorrhage.

    PubMed

    Jones, R M; de Lloyd, L; Kealaher, E J; Lilley, G J; Precious, E; Burckett St Laurent, D; Hamlyn, V; Collis, R E; Collins, P W

    2016-06-01

    Limited data exist on platelet transfusion during postpartum haemorrhage. We retrospectively analysed a consecutive cohort from a single centre of 347 women with moderate or severe postpartum haemorrhage, transfused according to national guidelines. Twelve (3%) women required a platelet transfusion. There were no differences between women who did and did not receive platelets with respect to age, mode of initiation of labour or mode of delivery. Women receiving a platelet transfusion had a lower median (IQR [range]) platelet count at study entry than women who did not receive platelets before haemorrhage (135 (97-175 [26-259])×10(9) .l(-1) vs 224 (186-274 [91-1006])×10(9) .l(-1) ), respectively), and at diagnosis of postpartum haemorrhage (median 114 (78-153 [58-238])×10(9) .l(-1) vs 193 (155-243 [78-762])×10(9) .l(-1) respectively). Six women were thrombocytopenic pre-delivery. The cause of haemorrhage that was associated with the highest rate of platelet transfusion was placental abruption, with three of 14 women being transfused. If antenatal thrombocytopenia or consumptive coagulopathy were not present, platelets were only required for haemorrhage > 5000 ml. Early formulaic platelet transfusion would have resulted in many women receiving platelets unnecessarily. Using current guidelines, the need for platelet transfusion is uncommon without antenatal thrombocytopenia, consumptive coagulopathy or haemorrhage > 5000 ml. We found no evidence to support early fixed-ratio platelet transfusion.

  17. Platelet Counts and Patent Ductus Arteriosus in Preterm Infants: A Systematic Review and Meta-Analysis.

    PubMed

    Simon, Sorina R; van Zogchel, Lieke; Bas-Suárez, Maria Pilar; Cavallaro, Giacomo; Clyman, Ronald I; Villamor, Eduardo

    2015-01-01

    Several cohort studies have shown an association between low platelet counts in the first day(s) of life and patent ductus arteriosus (PDA) in preterm infants. However, these results have not been confirmed by other studies. To perform a meta-analysis of all the studies addressing the relationship between platelet counts in the first day(s) of life and PDA in preterm infants. PubMed/MEDLINE and EMBASE were searched from their inception until December 2014. Results from 11 cohort studies involving 3,479 preterm infants (gestational age <32 weeks) were pooled using random-effects modeling. Meta-analysis showed a significant positive association between PDA and platelet counts <150 × 10(9)/l [6 studies, risk ratio (RR) = 1.215, 95% CI: 1.027-1.436], between PDA and platelet counts <100 × 10(9)/l (5 studies, RR = 1.255, 95% CI: 1.034-1.525), and between significant PDA (SPDA) and platelet counts <100 × 10(9)/l (5 studies, RR = 1.254, 95% CI: 1.021-1.540). The association between SPDA and platelet counts <150 × 10(9)/l was not statistically significant (6 studies, RR = 1.289, 95% CI: 0.925-1.795). Pooled standard differences in mean platelet counts between infants with and without PDA/SPDA were not statistically different. This meta-analysis reveals a marginal but significant association between low platelet counts in the first day(s) of life and PDA/SPDA in very preterm infants. This association needs to be confirmed in prospective studies. © 2015 S. Karger AG, Basel.

  18. Increased Platelet-to-Lymphocyte Ratios and Low Relative Lymphocyte Counts Predict Appropriate Shocks in Heart Failure Patients with ICDs

    PubMed Central

    Balci, Kevser Gülcihan; Balci, Mustafa Mücahit; Arslan, Ugur; Açar, Burak; Maden, Orhan; Selcuk, Hatice; Selcuk, Timur

    2016-01-01

    Background Platelet-to-lymphocyte ratio (PLR) and relative lymphocyte count (L%) are commonly available tests that can be obtained from complete blood count. The aim of this study was to investigate the association between appropriate defibrillator therapy and PLR, and whether decreased lymphocyte count may predict appropriate implantable cardioverter defibrillator (ICD) shocks in heart failure (HF) patients. Methods A total of 147 patients with ischemic or non-ischemic HF who underwent ICD implantation for primary prevention were enrolled in this study. Peripheral venous blood samples were drawn on the same day as ICD implantation. White blood cell counts with differentials, red blood cell indices, and platelet counts were calculated with an automated blood cell counter. All patients were evaluated according to the presence of appropriate ICD therapy. Results Baseline ejection fraction was significantly lower in the appropriate shock received group (p = 0.040). Median PLR was significantly higher and L% was significantly lower in the appropriate shock received group (p < 0.001). In both ischemic and non-ischemic HF groups, median L% was significantly lower in the appropriate shock received group (p < 0.001; p = 0.006, respectively). In multivariable logistic regression analysis, only L% showed a strong association with appropriate shock therapy (p < 0.001). Conclusions Higher PLRs are related to appropriate shocks in patients that received ICD with lower EF. Furthermore, decreased L% is independently associated with appropriate shocks in HF. PMID:27713602

  19. [Association of preoperative platelet count with the prognosis of patients with colorectal cancer].

    PubMed

    Chen, Li-Ling; Zhang, Li; Li, Yue-Ling; Li, Xiao-Ling; Liu, Wen-Hui; Yan, Jin; Yang, Yan-Fang

    2016-04-01

    To explore the association between preoperative platelet count and the outcomes of patients with colorectal cancer (CRC). This study was conducted among a cohort of 486 CRC patients, who underwent surgery in Sichuan Provincial Cancer Hospital between January, 2010 and July, 2013 and were prospectively followed up for their outcomes. The association between preoperative platelet counts and clinicopathologic factors of the patients were analyzed. Survival analysis of the patients was performed using log-rank test, and the factors affecting the patients' outcomes were analyzed by univariate and multivariate analyses using the Cox proportional hazard model. In this cohort, preoperative platelet count was significantly associated with the tumor site, depth of tumor invasion (T), and distant metastasis (M) (all P<0.05). Log-rank tests showed that in patients with CRC and rectal cancer, the overall postoperative survival differed significantly between high and low preoperative platelet count groups (Χ(2)=8.813, P=0.003 and Χ(2)=5.110, P=0.024, respectively), but this difference was not observed in patients with colon cancer (P<0.05). Multivariate analysis indicated that CRC patients with a high preoperative platelet count had a higher risk of death compared to those with a low platelet level after adjustment for tumor site, tumor grade, TNM stage, vascular invasion, perineural invasion, and preoperative CEA level (RR=1.814, 95%CI: 1.056-3.115). In subgroup analysis, preoperative platelet count was identified as an independent prognostic factor in patients with rectal cancer (RR=2.718, 95% CI: 1.132-6.526), but not in patients with colon cancer (RR=1.396, 95%CI: 0.705-2.765). As an independent prognostic factor in CRC patients, preoperative platelet count may serve as an important indicator for predicting the outcomes of rectal cancer, but its prognostic value for colon cancer needs further clarification.

  20. Platelet Count Response to Helicobacter pylori Eradication in Iranian Patients with Idiopathic Thrombocytopenic Purpura

    PubMed Central

    Payandeh, Mehrdad; Sohrabi, Nasrollah; Zare, Mohammad Erfan; Kansestani, Atefeh Nasir; Hashemian, Amir Hossein

    2012-01-01

    Idiopathic thrombocytopenic purpura (ITP) is an autoimmune hematological disorder characterized by auto antibody-mediated platelet destruction. Although the main cause of ITP remains unclear, but its relationship with some infection was demonstrated. In recent years, many studies have demonstrated improvement of platelet counts in ITP patients after treating Helicobacter pylori infection. The aim of this study was to investigate the effects of H. pylori eradication on platelet count response in Iranian ITP patients. A total of 26 patients diagnosed with both ITP and H. pylori infection. ITP were diagnosed whose platelet counts were less than 100×103/μL. These patients were tested for H. pylori infection by Urea Breath Test and serum H. pylori antibody. All patients received triple therapy for 7 or 14 days to eradicate H. pylori infection. These patients followed for six months. Prevalence of H. pylori was 67.3%. H. pylori eradication achieved in 89.5% (26/29). Of the 26 patients, 15 (57.7%) exhibited a complete response (CR) and 11 (42.3%) were unresponsive. We did not find partial responders. There was a significant difference in the baseline platelet count of responders and non-responders patients (p<0.001). All responders had platelet count ≥50×103/μL and all non-responders had platelet count <50×103/μL. Results of this study revealed that eradication therapy of H. pylori infection can improve platelet counts in ITP patients especially with mild thrombocytopenia and support routine detection and treatment of H. pylori infection in ITP patients in populations with a high prevalence of this infection. PMID:22973500

  1. The Effect of Transjugular Intrahepatic Portosystemic Shunt on Platelet Counts in Patients With Liver Cirrhosis

    PubMed Central

    Zein, Nizar N.

    2017-01-01

    Thrombocytopenia is a well-known complication of liver cirrhosis. Although the pathogenesis of thrombocytopenia is not well understood, splenic congestion resulting from portal hypertension is considered the most significant underlying mechanism. Therapeutic measures that lower portal hypertension, such as transjugular intrahepatic portosystemic shunt (TIPS), are expected to improve thrombocytopenia associated with liver cirrhosis. At present, there are few studies on the effect of TIPS on platelet counts, and the results are conflicting. This article assesses the effect of TIPS on thrombocytopenia associated with liver cirrhosis. Methods: Seventy-four patients with liver cirrhosis who were referred for TIPS were included in this study. Platelet counts were measured on 3 different occasions over a 3-month period prior to and following placement of TIPS. Thrombocytopenia was defined as a platelet count of 150,000/mm3 or less. Moderate thrombocytopenia was defined as a platelet count of 100,000/mm3 or less. Severe thrombocytopenia was defined as a platelet count of 50,000/mm3 or less. A significant increase in platelet count was defined as a 20% or higher increase from pre-TIPS values. The portosystemic pressure gradient (PSPG) was measured before and after placement of TIPS. The patency of the shunt was checked using Doppler ultrasound 24 hours and 3 months after the procedure. Results: Thirty-four of the 74 patients (46%) who underwent TIPS showed a significant increase in platelet count, with an average increase of 22% (P<.0005). Twenty-five of 40 patients (62%) with moderate thrombocytopenia showed a significant increase in platelet count, with an average increase of 36% (P<.0005). Patients with severe thrombocytopenia showed the greatest response to TIPS; 8 of 11 patients (73%) had a significant increase in platelet count (average increase, 55%; P<.0005). No correlation was found between the response to TIPS and age, sex, etiology of liver disease, pre-TIPS PSPG

  2. Platelet count can predict metabolic syndrome in older women.

    PubMed

    Chen, Yen-Lin; Hung, Yi-Jen; He, Chih-Tsueng; Lee, Chien-Hsing; Hsiao, Fone-Ching; Pei, Dee; Hsieh, Chang-Hsun

    2015-01-01

    Platelet count (PC) has been found to be related to the metabolic syndrome (MetS). However, the role of PC on MetS remained unclear. In order to evaluate the relationship between PC and MetS components cross-sectionally and determine the optimal cutoff PCs for predicting the subsequent risk of MetS development with sex specificity, two stages included cross-sectional (stage 1) and prospective (stage 2) cohort study were conducted. Stage 1 involved 10 579 subjects aged ≥60 years, of which 7718 subjects advanced to stage 2 with a mean 3.8 year follow-up were enrolled. The MetS components and PC were determined. The PC cutoffs for higher chances of developing MetS in stage 1 were calculated using receiver operating characteristic (ROC) curve analyses. In stage 2, non-MetS subjects were classified into high-PC (HPC) and low-PC (LPC) groups according to the cutoff values from stage 1. We examined the difference of future MetS incidence and calculated the odds ratio (OR) between these two groups. In stage 1, multiple regression showed that age and triglyceride (both sexes) and waist circumstance and high-density lipoprotein cholesterol (only women) were independently correlated with PC. There was significant difference in the area under the ROC curve (AUC) only of HPC women, which exceeded the standard curve (AUC = 0.542, p < 0.001), with a cutoff PC of 223 × 10(3)/μl. HPC women had an OR of 1.287 (95% confidence interval: 1.135-1.461) of developing MetS after 3.8 years. The Kaplan-Meier curve demonstrated a higher incidence of MetS development in HPC women. In conclusion, our results suggest that PC was associated with MetS with sex effects. Most of the MetS components were independent factors for increasing PC, and the risk for subsequent development of MetS was noted when PC >223 × 10(3)/μl in elderly women.

  3. Does platelet count in platelet-rich plasma influence slope, maximal amplitude and lag phase in healthy individuals? Results of light transmission aggregometry.

    PubMed

    Chandrashekar, Vani

    2015-01-01

    Light transmission aggregometry lacks in standardisation and normal reference values are not widely available. The aims of our study were to establish reference ranges for aggregation, slope and lag phase in healthy controls with platelet counts between 150 and 450 × 10(9)/l in platelet-rich plasma (PRP) as well as evaluate the influence of platelet count. Ninety-nine subjects were evaluated with four agonists and divided into two groups based on platelet count and the groups were compared by Student's t-test. There was no difference between the means of the two groups for amplitude and slope barring the lag phase for collagen. Platelet counts between 150 and 450 × 10(9)/l have no effects on light transmission aggregometry and hence adjustment of platelet count is not necessary.

  4. Low platelet counts after liver transplantation predict early posttransplant survival: the 60-5 criterion.

    PubMed

    Lesurtel, Mickaël; Raptis, Dimitri A; Melloul, Emmanuel; Schlegel, Andrea; Oberkofler, Christian; El-Badry, Ashraf Mohammad; Weber, Annina; Mueller, Nicolas; Dutkowski, Philipp; Clavien, Pierre-Alain

    2014-02-01

    Platelets play a critical role in liver injury and regeneration. Thrombocytopenia is associated with increases in postoperative complications after partial hepatectomy, but it is unknown whether platelet counts could also predict outcomes after transplantation, a procedure that is often performed in thrombocytopenic patients. Therefore, the aim of this study was to evaluate whether platelet counts could be indicators of short- and long-term outcomes after liver transplantation (LT). Two hundred fifty-seven consecutive LT recipients (January 2003-December 2011) from our prospective database were analyzed. Preoperative and daily postoperative platelet counts were recorded until postoperative day 7 (POD7). Univariate and multivariate analyses were performed to assess whether low perioperative platelet counts were a risk factor for postoperative complications and graft and patient survival. The median pretransplant platelet count was 88 × 10(9) /L [interquartile range (IQR) = 58-127 × 10(9) /L]. The lowest platelet counts occurred on POD3: the median was 56 × 10(9) /L (IQR = 41-86 × 10(9) /L). Patients with low platelet counts on POD5 had higher rates of severe (grade IIIb/IV) complications [39% versus 29%, odds ratio (OR) = 1.09 (95% CI = 1.1-3.3), P = 0.02] and 90-day mortality [16% versus 8%, OR = 2.25 (95% CI = 1.0-5.0), P = 0.05]. In the multivariate analysis, POD5 platelet counts < 60 × 10(9) /L were identified as an independent risk factor for grade IIIb/IV complications [OR = 1.96 (95% CI = 1.07-3.56), P = 0.03)], graft survival [hazard ratio (HR) = 2.0 (95% CI = 1.1-3.6), P = 0.03)], and patient survival [HR = 2.2 (95% CI = 1.1-4.6), P = 0.03)]. The predictive value of platelet counts for graft and patient survival was lost in patients who survived 90 days. In conclusion, after LT, platelet counts < 60 × 10(9) /L on POD5 (the 60-5 criterion) are an independent factor associated

  5. Platelets for neonatal transfusion - study 2: a randomised controlled trial to compare two different platelet count thresholds for prophylactic platelet transfusion to preterm neonates.

    PubMed

    Curley, Anna; Venkatesh, Vidheya; Stanworth, Simon; Clarke, Paul; Watts, Timothy; New, Helen; Willoughby, Karen; Khan, Rizwan; Muthukumar, Priya; Deary, Alison

    2014-01-01

    Neonatal thrombocytopenia is a common and important clinical problem in preterm neonates. A trial assessing clinically relevant outcomes in relation to the different platelet count thresholds used to trigger transfusion has never been undertaken in preterm neonates with severe thrombocytopenia. Platelets for Neonatal Transfusion - Study 2 (PlaNeT-2) aims to assess whether a higher prophylactic platelet transfusion threshold is superior to the lower thresholds in current standard practice in reducing the proportion of patients who have a major bleed or die up to study day 28. PlaNeT-2 is a two-stage, randomised, parallel-group, superiority trial. PlaNet-2 compares clinical outcomes in preterm neonates (<34 weeks' gestation at birth) randomised to receive prophylactic platelet transfusions to maintain platelet counts at or above either 25 × 10(9)/l or 50 × 10(9)/l. The primary outcome measure is the proportion of patients who either die or experience a major bleed up to and including study day 28. A total of 660 infants will be randomised. This trial will help define optimal platelet transfusion support for severely thrombocytopenic preterm neonates by evaluating the risks and benefits of two different prophylactic neonatal platelet transfusion thresholds. © 2014 S. Karger AG, Basel.

  6. Automated counting of bacterial colony forming units on agar plates.

    PubMed

    Brugger, Silvio D; Baumberger, Christian; Jost, Marcel; Jenni, Werner; Brugger, Urs; Mühlemann, Kathrin

    2012-01-01

    Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates.A colony counter hardware was designed and a novel segmentation algorithm was written in MATLAB. In brief, pre-processing with Top-Hat-filtering to obtain a uniform background was followed by the segmentation step, during which the colony images were extracted from the blood agar and individual colonies were separated. A Bayes classifier was then applied to count the final number of bacterial colonies as some of the colonies could still be concatenated to form larger groups. To assess accuracy and performance of the colony counter, we tested automated colony counting of different agar plates with known CFU numbers of S. pneumoniae, P. aeruginosa and M. catarrhalis and showed excellent performance.

  7. Automated Counting of Bacterial Colony Forming Units on Agar Plates

    PubMed Central

    Brugger, Silvio D.; Baumberger, Christian; Jost, Marcel; Jenni, Werner; Brugger, Urs; Mühlemann, Kathrin

    2012-01-01

    Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates. A colony counter hardware was designed and a novel segmentation algorithm was written in MATLAB. In brief, pre-processing with Top-Hat-filtering to obtain a uniform background was followed by the segmentation step, during which the colony images were extracted from the blood agar and individual colonies were separated. A Bayes classifier was then applied to count the final number of bacterial colonies as some of the colonies could still be concatenated to form larger groups. To assess accuracy and performance of the colony counter, we tested automated colony counting of different agar plates with known CFU numbers of S. pneumoniae, P. aeruginosa and M. catarrhalis and showed excellent performance. PMID:22448267

  8. An automated approach for annual layer counting in ice cores

    NASA Astrophysics Data System (ADS)

    Winstrup, M.; Svensson, A. M.; Rasmussen, S. O.; Winther, O.; Steig, E. J.; Axelrod, A. E.

    2012-11-01

    A novel method for automated annual layer counting in seasonally-resolved paleoclimate records has been developed. It relies on algorithms from the statistical framework of hidden Markov models (HMMs), which originally was developed for use in machine speech recognition. The strength of the layer detection algorithm lies in the way it is able to imitate the manual procedures for annual layer counting, while being based on statistical criteria for annual layer identification. The most likely positions of multiple layer boundaries in a section of ice core data are determined simultaneously, and a probabilistic uncertainty estimate of the resulting layer count is provided, ensuring an objective treatment of ambiguous layers in the data. Furthermore, multiple data series can be incorporated and used simultaneously. In this study, the automated layer counting algorithm has been applied to two ice core records from Greenland: one displaying a distinct annual signal and one which is more challenging. The algorithm shows high skill in reproducing the results from manual layer counts, and the resulting timescale compares well to absolute-dated volcanic marker horizons where these exist.

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

    PubMed

    Hurtado-Roca, Yamilee; Ledesma, Marta; 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.

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

    PubMed Central

    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. Evaluation of blood platelet count and function in patients with erectile dysfunction.

    PubMed

    Aldemir, M; Akdemir, F; Okulu, E; Ener, K; Ozayar, A; Gudeloglu, A

    2016-03-01

    We evaluated and compared blood total platelet count, mean platelet volume (MPV) and platelet distribution width (PDW) values of patients with erectile dysfunction (ED) and control subjects. A total 57 male patients (mean age 49.7 ± 12 years) with ED and 59 control men (mean age 49.7 ± 10.7 years) were included in the study. All patients were evaluated using medical history with International Index of Erectile Function (IIEF) scores, physical examination and routine blood analysis. Total blood count, including white blood cell (WBC), total platelet counts, MPV and PDW parameters, were recorded in both groups. MPV values were detected to be significantly higher in patients with ED than control group: 10.7 ± 1 and 9.72 ± 1.5, respectively (P = 0.001). Similarly, PDW values were significantly higher in patients with ED than control group: 14.6 ± 2.8 and 12.9 ± 1.9, respectively (P = 0.001). However, mean platelet and mean WBC counts were similar in both groups (P = 0.45). We demonstrated that MPV and PDW values significantly increased in patients with ED compared with the control group. According to these findings, platelet function might play an important role in patients with ED that warrants further research.

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

    PubMed

    Li, Lei; Han, Jiang-li; Li, Hai-yan; Qiao, Rui; Yu, Hai-yi; Zhang, Jie; Gao, Wei

    2013-03-26

    To explore the association between clopidogrel resistance (CR) as assessed by whole blood electrical impedance aggregometry (EIA) and platelet parameters. The prospective study comprised 152 patients with coronary artery disease (CAD) on the therapy of clopidogrel. EIA employed adenosine diphosphate (ADP) as an inductor to measure platelet aggregation. CR was defined by spontaneous aggregation (electrical impedance ≥ 10 Ω). The subjects were divided into 2 groups of CR and clopidogrel sensitive (CS). Platelet parameters were measured by routine blood test. And their clinical data and outcomes were analyzed. The prevalence of CR was 10.5% (n = 16). The ratio of patients with diabetes in CR group was higher than that in CS group (7/16 vs 29/136, P = 0.046). Platelet counts and mean platelet volume (MPV) were also higher in CR group than those in CS group ((241 ± 58) ×10(9)/L vs (185 ± 56)×10(9)/L, (8.0 ± 0.8) fl vs (7.4 ± 0.9) fl, both P < 0.05). Logistic regression indicated each 10×10(9)/L increase in platelet and each 1 fl increase in MVP were associated with 0.376 and 1.015 folds increase in CR onset respectively (OR = 1.376, 95%CI 1.097 - 1.725, P = 0.006;OR = 2.015, 95%CI 1.148 - 3.537, P = 0.015). The patients with CR had more cardiovascular events during an average follow-up of 53 months (6/16 vs 23/136, P = 0.047). CAD patients with CR had higher incidence of cardiovascular events. Increased platelet counts and MPV levels are independent predictors for CR in CAD patients.

  13. Correlation of platelets count with endoscopic findings in a cohort of Egyptian patients with liver cirrhosis.

    PubMed

    Abd-Elsalam, Sherief; Habba, Eslam; Elkhalawany, Walaa; Tawfeek, Salwa; Elbatea, Hassan; El-Kalla, Ferial; Soliman, Hanan; Soliman, Samah; Yousef, Mohamed; Kobtan, Abdelrahman; El Nawasany, Sally; Awny, Sheren; Amer, Ibrahim; Mansour, Loai; Rizk, Fatma

    2016-06-01

    Screening endoscopy is recommended for early detection of esophageal varices (EVs) in cirrhotic patients with portal hypertension. However, this approach is limited by its invasiveness and cost. The aim of the study was to determine if platelet count can predict the presence of EVs, especially large (grade III, IV) EVs in need of prophylactic therapy, in a cohort of Egyptian patients with liver cirrhosis. In all, 110 patients with cirrhosis were prospectively analyzed. The presence of medium or large EVs was correlated with patients' platelet count and FIB-4. Esophageal varices were present in 87 (79.09%) patients. Among those with thrombocytopenia (platelet level below 150,000), 25.97% (20 patients) and 27.27% (21 patients) had EV grade II and EV grade III or IV, respectively. Whereas in patients in whom the platelet count was above 150,000, only 21.21% (7 patients) and 9.09% (3 patients) of patients had grade II EV and EV grade III or IV, respectively. A platelet count cut-off value of 149,000 was found to have specificity of 82% and sensitivity 39% for detection of presence of varices. A FIB-4 cut-off value of 3.175 was found to have an 83.3% sensitivity and 39.5% specificity in detecting large (grade III, IV) EVs. Platelet count is a noninvasive parameter with high accuracy for prediction of EVs. Cirrhotic patients with normal platelet counts (above 150,000), especially in financially deprived developing countries, can avoid screening endoscopy as they are at a low risk for variceal bleeding, and presence of large EVs in these patients is much less common than in those with thrombocytopenia. A 3.175 cut-off value of FIB-4 could be useful as a noninvasive predictor of large varices requiring prophylactic banding in cirrhotic patients.

  14. From Crater to Graph: Manual and Automated Crater Counting Techniques

    NASA Astrophysics Data System (ADS)

    Plesko, C. S.; Werner, S. C.; Brumby, S. P.; Foing, B. H.; Asphaug, E.; Neukum, G.; Team, H.; Team, I.

    2005-12-01

    Impact craters are some of the most abundant, and most interesting features on Mars. They hold a wealth of information about Martian geology, providing clues to the relative age, local composition and erosional history of the surface. A great deal of effort has been expended to count and understand the nature of planetary crater populations (Hartman and Neukum, 2001). Highly trained experts have developed personal methods for conducting manual crater surveys. In addition, several efforts are underway to automate this process in order to keep up with the rapid increase in planetary surface image data. These efforts make use of a variety of methods, including the direct application of traditional image processing algorithms such as the Hough transform, and recent developments in genetic programming, an artificial intelligence-based technique, in which manual crater surveys are used as examples to `grow' or `evolve' crater counting algorithms. (Plesko, C. S. et al., LPSC 2005, Kim, J. R. et al., LPSC 2001, Michael, G. G. P&SS 2003, Earl, J. et al, LPSC 2005) In this study we examine automated crater counting techniques, and compare them with traditional manual techniques on MOC imagery, and demonstrate capabilities for the analysis of multi-spectral and HRSC Digital Terrain Model data as well. Techniques are compared and discussed to define and develop a robust automated crater detection strategy.

  15. Preoperative Platelet Count Associates with Survival and Distant Metastasis in Surgically Resected Colorectal Cancer Patients

    PubMed Central

    Wan, Shaogui; Lai, Yinzhi; Myers, Ronald E.; Li, Bingshan; Hyslop, Terry; London, Jack; Chatterjee, Devjani; Palazzo, Juan P.; Burkart, Ashlie L.; Zhang, Kejin; Xing, Jinliang

    2013-01-01

    Objective Platelets have been implicated in cancer metastasis and prognosis. No population-based study has been reported as to whether preoperative platelet count directly predicts metastatic recurrence of colorectal cancer (CRC) patients. Design Using a well-characterized cohort of 1,513 surgically resected CRC patients, we assessed the predictive roles of preoperative platelet count in overall survival, overall recurrence, as well as locoregional and distant metastatic recurrences. Results Patients with clinically high platelet count (≥400× 109/L) measured within 1 month before surgery had a significantly unfavorable survival (hazard ratio [HR]=1.66, 95 % confidence interval [CI] 1.34–2.05, P=2.6×10−6, Plog rank= 1.1×10−11) and recurrence (HR=1.90, 1.24–2.93, P=0.003, Plog rank=0.003). The association of platelet count with recurrence was evident only in patients with metastatic (HR=2.81, 1.67–4.74, P=1.1×10−4, Plog rank =2.6×10−6) but not locoregional recurrence (HR=0.59, 95 % CI 0.21–1.68, P= 0.325, Plog rank=0.152). The findings were internally validated through bootstrap resampling (P<0.01 at 98.6 % of resampling). Consistently, platelet count was significantly higher in deceased than living patients (P<0.0001) and in patients with metastatic recurrence than locoregional (P= 0.004) or nonrecurrent patients (P<0.0001). Time-dependent modeling indicated that the increased risks for death and metastasis associated with elevated preoperative platelet counts persisted up to 5 years after surgery. Conclusion Our data demonstrated that clinically high level of preoperative platelets was an independent predictor of CRC survival and metastasis. As an important component of the routinely tested complete blood count panel, platelet count may be a cost-effective and noninvasive marker for CRC prognosis and a potential intervention target to prevent metastatic recurrence. PMID:23549858

  16. Improving guideline compliance: assessment of unit-based reminder for monitoring platelet counts post-PCI.

    PubMed

    Belletti, Daniel; Bolash, Robert B; Arcona, Stephen; Reed, James F

    2002-01-01

    In assessing our institution's vascular access site bleeding complication rate, we found (anecdotally) that for many patients platelet count was not measured according to recommendations of the manufacturer of the predominantly used glycoprotein (GP) IIb/IIIa agents, in either the catheterization recovery unit (CRU) or the coronary care unit (CCU). We hypothesized that a unit-focused effort to remind cardiologists to order platelet counts after percutaneous coronary interventions GP IIb/IIIa would improve compliance. Findings indicated that a greater number of patients had platelet counts drawn after a reminder effort had been implemented. For both the first and second draws, the CCU had a higher pre-reminder rate than the CRU. Post-reminder, the CCU had no significant changes, whereas the CRU showed significant increases in both the first and second draws. For post GP IIb/IIIa platelet measurement, aggregate analysis (CRU and CCU) showed that, of those patients who had platelet counts drawn pre-reminder, only 18.2% met the first guideline and only 17.1% met the second. Post-reminder results showed no significant changes for the first or second draws. We concluded that the practical application of a standard operating procedure can have a secondary beneficial effect despite not meeting the stringent parameters set in prescribing guidelines.

  17. Elevated pretreatment plasma D-dimer levels and platelet counts predict poor prognosis in pancreatic adenocarcinoma.

    PubMed

    Liu, Peng; Zhu, Yuan; Liu, Luying

    2015-01-01

    This retrospective study was conducted to evaluate the prognostic significance of the preoperative plasma D-dimer levels and platelet counts in patients with pancreatic adenocarcinoma. A total of 168 consecutive locally advanced pancreatic adenocarcinoma patients who underwent intensity modulated radiation therapy with or without chemotherapy were enrolled in this study. Plasma D-dimer levels were measured by a latex-enhanced immunoturbidimetric assay. Of the 168 patients enrolled, 106 patients were males and 62 patients were females. There was significant difference between plasma D-dimer levels and clinical responses (P=0.001). The 1-year, 2-year, and 3-year cumulative overall survival rates were 50.6%, 15.0%, and 4.9%, respectively. Plasma D-dimer levels (P<0.001) and platelet counts (P=0.010) were significantly related with overall survival in univariate analysis. The Cox proportional hazards regression indicated that plasma D-dimer levels (P=0.028), platelet counts (P=0.004), and treatment response (P<0.001) were independent prognostic factors for overall survival. Elevated pretreatment plasma D-dimer levels and platelet counts predict poor prognosis in pancreatic adenocarcinoma.

  18. Platelet count increase following phlebotomy in iron overloaded patients with liver cirrhosis.

    PubMed

    Franchini, Massimo

    2003-08-01

    Thrombocytopenia is a frequent hematological complication in patients with liver cirrhosis, but its pathogenesis is not clearly understood. We evaluated the effect of iron depletion by phlebotomy on platelet count in 62 consecutive iron overloaded patients with liver cirrhosis and thrombocytopenia. After a median follow-up of 30.2 months we observed a significant increase of platelet count in all patients (from mean baseline levels of 110.1 up to 168.22109/l at the end of follow-up, P<0.001) with platelet count normalization in 42 of them (67.7%). In addition, we observed a significant improvement of serum ALT levels (from pretreatment mean values of 126.7 up to 59.7 U/l at the end of follow-up, P<0.001) along with the reduction of serum ferritin levels and transferrin saturation during phlebotomy. Different pathogenetic mechanisms involving both humoral (erythropoietin and thrombopoietin, TPO) and physical (portal hypertension and hypersplenism) factors are here discussed to explain the platelet count increase following phlebotomy. Our results show that phlebotomy is effective not only in lowering iron overload, but also in improving liver function and thrombocytopenia in patients with liver cirrhosis.

  19. Hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome with pituitary apoplexy.

    PubMed

    Murao, Koji; Imachi, Hitomi; Muraoka, Tomie; Ishida, Toshihiko

    2011-07-01

    After hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome was diagnosed in a 35-year-old woman at 39 weeks' gestation, magnetic resonance imaging and hormone examination revealed pituitary apoplexy with panhypopituitarism and diabetes insipidus. Evaluation of pituitary function should be considered in patients with HELLP syndrome.

  20. Effect of quinine and artesunate combination therapy on platelet count of children with severe malaria.

    PubMed

    Gupta, Parul; Narang, Manish; Gomber, Sunil; Saha, Rumpa

    2017-05-01

    There are several case reports of quinine-induced thrombocytopenia but no clinical trials to ascertain its incidence and significance in severe malaria. The primary objective was to assess the effect of quinine on the platelet count in children with severe malaria and to compare it with artesunate combination therapy (ACT), and the secondary objective was to assess outcome of treatment with quinine and ACT. An open-labelled, randomised, controlled trial was undertaken in 100 children aged 6 months to 12 years who were diagnosed with malaria by microscopy and/or rapid diagnostic test kits with at least one WHO clinical or laboratory criterion for severe malaria. All subjects were commenced on either quinine or ACT. Clindamycin was added to artesunate as a combination drug (ACT). It was also given to patients on quinine to avoid its confounding effect on the results. Platelet counts were undertaken every 24 hours for 7 consecutive days, temperature and coma score (Blantyre coma score ≥3 in children <4 years or Glasgow coma score ≥13 in children >4 years) was recorded 6-hourly and peripheral smears were taken 12-hourly until two consecutively negative smears were obtained. The primary outcome was a fall in the platelet count by ≥20% from the time of drug initiation until day 7. The secondary outcome was comparison of the efficacy, parasite clearance time, fever clearance time, coma recovery time and adverse effects of quinine vs ACT. 30.4% patients in the quinine group (n = 48) had ≥20% fall in platelet count and 10.8% of patients in the ACT group (n = 46) (P = 0.02). Despite the fall in platelet count, there was no bleeding. The efficacy of ACT was significantly better than quinine but the other treatment outcomes showed insignificant difference. Quinine should be used with caution in patients with severe malaria because of the potential risk of quinine-induced thrombocytopenia.

  1. Beyond the platelet count: immature platelet fraction and thromboelastometry correlate with bleeding in patients with immune thrombocytopenia.

    PubMed

    Greene, Lindsey A; Chen, Siqi; Seery, Caroline; Imahiyerobo, Allison M; Bussel, James B

    2014-08-01

    Platelet counts (PC) estimate bleeding risk in Immune Thrombocytopenia (ITP). We investigated whether measures of thromboelastometry and absolute immature platelet fraction (A-IPF) would correlate better with acute bleeding score (ABS) than PC or mean platelet volume (MPV). Simultaneous determination of ABS, complete blood count and thromboelastometry was performed in 141 ITP patients; 112 underwent A-IPF testing. Subgroup analyses were performed for paediatric subjects, PC <60 × 10(9) /l and <30 × 10(9) /l. PC significantly inversely correlated with ABS in all subjects, PC <30 × 10(9) /l and total paediatric cohort. MPV did not correlate with ABS in any subgroup. Thromboelastometry measures of clot firmness, but not PC, significantly correlated with ABS in all subjects with PC <60 × 10(9) /l, and children with PC <60 × 10(9) /l and <30 × 10(9) /l. A-IPF demonstrated stronger correlation with ABS than did PC among all subjects, those with PC <60 × 10(9) /l, all children and children with PC <30 × 10(9) /l (r = -0·37; r = -0·34; r = -0·44; r = -0·60) versus ABS with PC (r = -0·36; ns; r = -0·32; ns). Stronger correlations of both thromboelastometry measures of clot firmness and A-IPF than PC with ABS suggest factors beyond PC, i.e. related to platelet function, contribute to ITP bleeding pathophysiology. Thromboelastometry, A-IPF and ABS can be incorporated into routine or acute visits.

  2. Thymidine phosphorylase gene variant, platelet counts and survival in gastrointestinal cancer patients treated by fluoropyrimidines

    PubMed Central

    Huang, Liu; Chen, Fengju; Chen, Yangyang; Yang, Xiaomei; Xu, Sanpeng; Ge, Shuwang; Fu, Shengling; Chao, Tengfei; Yu, Qianqian; Liao, Xin; Hu, Guangyuan; Zhang, Peng; Yuan, Xianglin

    2014-01-01

    The predictive value of thymidine phosphorylase gene variants (TP, also called platelet-derived endothelial cell growth factor) and thrombocytosis were controversial and worthy of further study in gastrointestinal cancer (GIC) patients. We screened all of the common missense single nucleotide polymorphisms (MAF ≥ 0.1) in fluoropyrimidines (FU) pathway genes (including TP, TS, ENOSF1 and DPD). Three of them were selected and genotyped using Sequenom MassARRAY in 141 GIC patients. TP expression was assessed by immunohistochemistry. Our aim was to evaluate the prognostic significance of studied genes and platelet counts in GIC patients. Multivariate analyses indicated in rs11479-T allele carriers, platelet counts negatively correlated to overall survival. In addition, T allele of TP: rs11479 was associated with higher TP expression in cancer tissues. We suggest TP: rs11479 variant combined with platelet counts may be useful prognostic makers in GIC patients receiving first-line FU chemotherapy and thrombopoietin factor should be used with caution in the rs11479 T allele bearing patients. PMID:25027354

  3. Platelet count recovery after intravenous immunoglobulin predicts a favorable outcome in children with immune thrombocytopenia

    PubMed Central

    Ji, Mi Hong; Kim, Sung Jin; Ahn, Hyo Seop

    2016-01-01

    Background Childhood immune thrombocytopenic purpura (ITP) is a common acquired bleeding disorder. Even though most children recover, either spontaneously or with therapy, 10-20% of newly diagnosed ITP cases have a chronic course beyond 12 months. This study evaluated whether clinical and laboratory findings can predict the response to intravenous immunoglobulin (IVIG) and progression to persistent or chronic ITP in children. Methods During the period between March 2003 and June 2015, we retrospectively analyzed 72 children, newly diagnosed with ITP, who received IVIG treatment. Peripheral blood counts were obtained at diagnosis and at 1, 3, 6, and 12 months after IVIG treatment. Results After 6 months of IVIG treatment, 14 of 72 patients (19.4%) had persistent ITP, and after 12 months, 7 of 40 patients (17.5%) had chronic ITP. Age at diagnosis, gender, history of viral infection, or vaccination before disease onset were not statistically correlated with platelet recovery at 6 and 12 months. However, a platelet count recovery of ≥100×103/µL at 1 and 3 months was significantly correlated with platelet recovery at 6 (P<0.001 and P<0.001, respectively) and 12 (P=0.007 and P=0.004, respectively) months. Conclusion This study demonstrated that early platelet count recovery, at 1 and 3 months after IVIG treatment, predicts a short disease duration and a favorable outcome in children with newly diagnosed ITP. Further investigation in a larger group of patients is warranted to validate these findings. PMID:27382553

  4. An Automated Method for Annual Layer Counting in Ice Cores

    NASA Astrophysics Data System (ADS)

    Winstrup, M.; Svensson, A.

    2010-12-01

    The Greenland ice cores provide a wealth of data on past changes in climate, and have - compared to most other paleoclimatic archives - the potential to be dated very accurately by annual layer counting. An effort of manually doing annual layer counting using multiple chemical components has resulted in the Greenland Ice Core Chronology (GICC05), common to several Greenland deep ice cores. The oldest part of the chronology is based on data from the NGRIP ice core, which has a particularly fine yearly data resolution with depth. However, due to the increased thinning of annual layers with depth, the annual layers in most components are no longer recognizable in the ice core for depths below 2430m, corresponding to an age of 60 ka. At this depth, only the annual layering in the visual stratigraphy is still intact, but due to a high noise-level in these data, it is difficult manually to do annual layer counting only using this data record. In this study, an automated method has been developed, which takes into account the underlying statistical properties of the visual stratigraphy data sequence, and hereby is able to detect layers otherwise unrecovered. The data sequence is modeled using a Hidden Markov Model (HMM), with algorithms otherwise mainly applied to speech recognition. Preliminary studies are promising, and even crude implementations of the method agree to within 90% of the GICC05 counting. Due to more noise in the visual stratigraphy data during warm periods, the method is likely to give better results in cold periods than during warm. However, as the annual layers are thicker during warm periods, it seems to be possible to use other parameters than the visual stratigraphy for counting annual layers during these. Using the combined data, it should therefore be possible to develop a high-resolution timescale for the NGRIP ice core extending back to at least 90 ka. In the future, a similar approach might be used for a general multi-parameter annual layer

  5. Depression of platelet counts in apparently healthy children with asymptomatic malaria infection in a Nigerian metropolitan city.

    PubMed

    Jeremiah, Zaccheaus Awortu; Uko, Emmanuel Kufre

    2007-09-01

    Asymptomatic malaria infection is a common feature of malaria endemic regions in the tropics. In this prospective cross sectional survey, involving 240 children aged 1 to 8 years (Boys = 117, Girls = 123; Ratio 1:1.05), the median platelet count was 115 x 10(9)/L (IQR 97.5-190). Thirty-three out of 240 (13.75%) of the children had thrombocytopenia (platelet count < 100 x 10(9)/L). Malaria parasite was found to exert significant reduction in platelet count. This reduction was more pronounced in children under 5 years and also at higher parasite counts. An inverse relationship was established between parasite density and platelet count (y = -0.017x + 96.2, r = -0.2). Thrombocytopenia is not only a feature of acute malaria infection but also that of asymptomatic malaria infection in the tropics and might be a useful indicator of malaria in children.

  6. Postoperative Decrease in Platelet Counts Is Associated with Delayed Liver Function Recovery and Complications after Partial Hepatectomy.

    PubMed

    Takahashi, Kazuhiro; Kurokawa, Tomohiro; Oshiro, Yukio; Fukunaga, Kiyoshi; Sakashita, Shingo; Ohkohchi, Nobuhiro

    2016-05-01

    Peripheral platelet counts decrease after partial hepatectomy; however, the implications of this phenomenon are unclear. We assessed if the observed decrease in platelet counts was associated with postoperative liver function and morbidity (complications grade ≤ II according to the Clavien-Dindo classification). We enrolled 216 consecutive patients who underwent partial hepatectomy for primary liver cancers, metastatic liver cancers, benign tumors, and donor hepatectomy. We classified patients as either low or high platelet percentage (postoperative platelet count/preoperative platelet count) using the optimal cutoff value calculated by a receiver operating characteristic (ROC) curve analysis, and analyzed risk factors for delayed liver functional recovery and morbidity after hepatectomy. Delayed liver function recovery and morbidity were significantly correlated with the lowest value of platelet percentage based on ROC analysis. Using a cutoff value of 60% acquired by ROC analysis, univariate and multivariate analysis determined that postoperative lowest platelet percentage ≤ 60% was identified as an independent risk factor of delayed liver function recovery (odds ratio (OR) 6.85; P < 0.01) and morbidity (OR, 4.90; P < 0.01). Furthermore, patients with the lowest platelet percentage ≤ 60% had decreased postoperative prothrombin time ratio and serum albumin level and increased serum bilirubin level when compared with patients with platelet percentage ≥ 61%. A greater than 40% decrease in platelet count after partial hepatectomy was an independent risk factor for delayed liver function recovery and postoperative morbidity. In conclusion, the decrease in platelet counts is an early marker to predict the liver function recovery and complications after hepatectomy.

  7. Platelet count and adhesiveness on induction to high altitude by air and road

    NASA Astrophysics Data System (ADS)

    Sharma, S. C.

    1982-09-01

    Platelet count and adhesiveness (PA) were estimated in 87 normal lowlanders at sea level. They were randomly divided in three groups. Group A was taken to 3 660 m by air, group B by rapid road ascent and group C by road after acclimatisation enroute. Estimations were repeated serially during stay at high altitude and then on return to sea level. The subjects were divided into “symptomatic” and “asymptomatic” groups based on their score on a symptom score chart. Some subjects of the air induced group (A) developed significant symptoms and showed a significant rise in PA on days 2 and 10 of exposure. Remaining subjects of group A and all subjects of road inducted group (B and C) remained asymptomatic and showed no change in PA. No significant change in the platelet counts in any of the lowlanders was noted on exposure to high altitude. The significance of these findings is discussed.

  8. Microfluidic cytometers with integrated on-chip optical systems for red blood cell and platelet counting.

    PubMed

    Zhao, Yingying; Li, Qin; Hu, Xiaoming; Lo, Yuhwa

    2016-11-01

    A microfluidic cytometer with integrated on-chip optical systems was designed for red blood cell (RBC) and platelet (PLT) counting. The design, fabrication, and characterization of the microfluidic cytometer with on-chip optical signal detection were described. With process using only a single mask, the device that integrates optical fibers and on-chip microlens with microfluidic channels on a polydimethylsiloxane layer by standard soft photolithography. This compact structure increased the sensitivity of the device and eliminated time-consuming free-space optical alignments. The microfluidic cytometer was used to count red blood cells and platelets. Forward scatter and extinction were collected simultaneously for each cell. Experimental results indicated that the microfluidic cytometer exhibited comparable performance with a conventional cytometer and demonstrated superior capacity to detect on-chip optical signals in a highly compact, simple, truly portable, and low-cost format that is well suitable for point-of-care clinical diagnostics.

  9. The use of regression analysis in determining reference intervals for low hematocrit and thrombocyte count in multiple electrode aggregometry and platelet function analyzer 100 testing of platelet function.

    PubMed

    Kuiper, Gerhardus J A J M; Houben, Rik; Wetzels, Rick J H; Verhezen, Paul W M; van Oerle, Rene; Ten Cate, Hugo; Henskens, Yvonne M C; Lancé, Marcus D

    2017-01-09

    Low platelet counts and hematocrit levels hinder whole blood point-of-care testing of platelet function. Thus far, no reference ranges for MEA (multiple electrode aggregometry) and PFA-100 (platelet function analyzer 100) devices exist for low ranges. Through dilution methods of volunteer whole blood, platelet function at low ranges of platelet count and hematocrit levels was assessed on MEA for four agonists and for PFA-100 in two cartridges. Using (multiple) regression analysis, 95% reference intervals were computed for these low ranges. Low platelet counts affected MEA in a positive correlation (all agonists showed r(2) ≥ 0.75) and PFA-100 in an inverse correlation (closure times were prolonged with lower platelet counts). Lowered hematocrit did not affect MEA testing, except for arachidonic acid activation (ASPI), which showed a weak positive correlation (r(2) = 0.14). Closure time on PFA-100 testing was inversely correlated with hematocrit for both cartridges. Regression analysis revealed different 95% reference intervals in comparison with originally established intervals for both MEA and PFA-100 in low platelet or hematocrit conditions. Multiple regression analysis of ASPI and both tests on the PFA-100 for combined low platelet and hematocrit conditions revealed that only PFA-100 testing should be adjusted for both thrombocytopenia and anemia. 95% reference intervals were calculated using multiple regression analysis. However, coefficients of determination of PFA-100 were poor, and some variance remained unexplained. Thus, in this pilot study using (multiple) regression analysis, we could establish reference intervals of platelet function in anemia and thrombocytopenia conditions on PFA-100 and in thrombocytopenia conditions on MEA.

  10. Platelet count/spleen diameter ratio to predict esophageal varices in Mexican patients with hepatic cirrhosis.

    PubMed

    González-Ojeda, Alejandro; Cervantes-Guevara, Gabino; Chávez-Sánchez, Manuela; Dávalos-Cobián, Carlos; Ornelas-Cázares, Susana; Macías-Amezcua, Michel Dassaejv; Chávez-Tostado, Mariana; Ramírez-Campos, Kenia Militzi; Ramírez-Arce, Anaís Del Rocío; Fuentes-Orozco, Clotilde

    2014-02-28

    To validate whether the platelet count/spleen size ratio can be used to predict the presence of esophageal varices in Mexican patients with hepatic cirrhosis. This was an analytical cross-sectional study to validate the diagnostic test for hepatic cirrhosis and was performed between February 2010 and December 2011. Patients with a diagnosis of hepatic cirrhosis were included and stratified using their Child-Pugh score. Biochemical parameters were evaluated, and ultrasound was used to measure the longest diameter of the spleen. The platelet count/spleen diameter ratio was calculated and analyzed to determine whether it can predict the presence of esophageal varices. Upper gastrointestinal endoscopy was used as the gold standard. Sensitivity and specificity, positive and negative predictive values, and positive and negative likelihood ratios were determined, with the cutoff points determined by receiver-operating characteristic curves. A total of 91 patients were included. The mean age was 53.75 ± 12 years; 50 (54.9%) were men, and 41 (45.0%) women. The etiology of cirrhosis included alcohol in 48 (52.7%), virally induced in 24 (26.3%), alcoholism plus hepatitis C virus in three (3.2%), cryptogenic in nine (9.8%), and primary biliary cirrhosis in seven (7.6%). Esophageal varices were present in 73 (80.2%) patients. Child-Pugh classification, 17 (18.6%) patients were classified as class A, 37 (40.6%) as class B, and 37 (40.6%) as class C. The platelet count/spleen diameter ratio to detect esophageal varices independent of the grade showed using a cutoff value of ≤ 884.3, had 84% sensitivity, 70% specificity, and positive and negative predictive values of 94% and 40%, respectively. Our results suggest that the platelet count/spleen diameter ratio may be a useful tool for detecting esophageal varices in patients with hepatic cirrhosis.

  11. Platelet count/spleen diameter ratio to predict esophageal varices in Mexican patients with hepatic cirrhosis

    PubMed Central

    González-Ojeda, Alejandro; Cervantes-Guevara, Gabino; Chávez-Sánchez, Manuela; Dávalos-Cobián, Carlos; Ornelas-Cázares, Susana; Macías-Amezcua, Michel Dassaejv; Chávez-Tostado, Mariana; Ramírez-Campos, Kenia Militzi; Ramírez-Arce, Anaís del Rocío; Fuentes-Orozco, Clotilde

    2014-01-01

    AIM: To validate whether the platelet count/spleen size ratio can be used to predict the presence of esophageal varices in Mexican patients with hepatic cirrhosis. METHODS: This was an analytical cross-sectional study to validate the diagnostic test for hepatic cirrhosis and was performed between February 2010 and December 2011. Patients with a diagnosis of hepatic cirrhosis were included and stratified using their Child-Pugh score. Biochemical parameters were evaluated, and ultrasound was used to measure the longest diameter of the spleen. The platelet count/spleen diameter ratio was calculated and analyzed to determine whether it can predict the presence of esophageal varices. Upper gastrointestinal endoscopy was used as the gold standard. Sensitivity and specificity, positive and negative predictive values, and positive and negative likelihood ratios were determined, with the cutoff points determined by receiver-operating characteristic curves. RESULTS: A total of 91 patients were included. The mean age was 53.75 ± 12 years; 50 (54.9%) were men, and 41 (45.0%) women. The etiology of cirrhosis included alcohol in 48 (52.7%), virally induced in 24 (26.3%), alcoholism plus hepatitis C virus in three (3.2%), cryptogenic in nine (9.8%), and primary biliary cirrhosis in seven (7.6%). Esophageal varices were present in 73 (80.2%) patients. Child-Pugh classification, 17 (18.6%) patients were classified as class A, 37 (40.6%) as class B, and 37 (40.6%) as class C. The platelet count/spleen diameter ratio to detect esophageal varices independent of the grade showed using a cutoff value of ≤ 884.3, had 84% sensitivity, 70% specificity, and positive and negative predictive values of 94% and 40%, respectively. CONCLUSION: Our results suggest that the platelet count/spleen diameter ratio may be a useful tool for detecting esophageal varices in patients with hepatic cirrhosis. PMID:24616574

  12. Identification and validation of a factor of commutability between platelet counts performed on EDTA and citrate.

    PubMed

    Dumont, Pierre; Goussot, Vincent; David, Alice; Lizard, Sarab; Riedinger, Jean-Marc

    2017-02-01

    The anticoagulant mostly employed for platelet count is EDTA. The Francophone Group of Cellular Hematology recommends checking of blood smear stained with May-Grünwald Giemsa any thrombocytopenia less than 100 G/L without medical history or whether an alarm is generated by the cell counter. The pseudo-thrombocytopenia (PTP) with EDTA is the best known artifact in platelet count. A sample of blood on citrated tube is necessary to get rid of the interference. The objective of this study was to compare the platelet counts obtained on EDTA (numEDTA) and citrate (numCTAD) tubes and to define, then validate a factor of conversion between both methods. The prevalence of PTP EDTA is 0.26%. The PTP was transient in 80% of the patients. The numEDTA and numCTAD+10% (numCTAD increased by 10% to take dilution into account) are correlated but are not equivalent. The numCTAD+10% underestimate numEDTA significantly. The systematic bias is removed if we increase by 17% numCTAD. The factor of correction is stable over a period of 3 hours.

  13. Impact of preoperative platelet count on perioperative outcome after laparoscopic splenectomy for idiopathic thrombocytopenic purpura.

    PubMed

    Martin Arnau, Belén; Turrado Rodriguez, Víctor; Tartaglia, Ernesto; Bollo Rodriguez, Jesús; Targarona, Eduardo M; Trias Folch, Manuel

    2016-01-01

    Laparoscopic splenectomy (LS) is the preferred treatment of idiopathic thrombocytopenic purpura (ITP) when medical treatment fails. The objective was to evaluate the feasibility and safety of LS according to the preoperative platelet count. This study is a retrospective analysis of a series of 199 patients who underwent LS for ITP from 1993 to 2015. The patients were divided into 3 groups according to platelet count: group i (<10×10(9)/L), group ii (10-50×10(9)/L) and group iii (> 50×10(9)/L). Operative time was significantly lower in Group III compared to Group I and II (100±53 and 105±61min, P<.025)). Intraoperative blood loss was statistically higher in group i (263±551ml) with respect to the other 2: group ii (128±352ml) and group iii (24±62ml) (P<.003). Hospital stay was 6.4±5.8 days in group i, significantly higher compared to groups ii and iii (3.8±2.3 and 3.2±1.8 days, respectively (P<.003)). Conducting a LS in ITP patients with low platelet counts is effective and safe. Publicado por Elsevier España, S.L.U.

  14. White blood cell count, sex and age are major determinants of heterogeneity of platelet indices in an adult general population: results from the MOLI-SANI project.

    PubMed

    Santimone, Iolanda; Di Castelnuovo, Augusto; De Curtis, Amalia; Spinelli, Maria; Cugino, Daniela; Gianfagna, Francesco; Zito, Francesco; Donati, Maria Benedetta; Cerletti, Chiara; de Gaetano, Giovanni; Iacoviello, Licia

    2011-08-01

    The understanding of non-genetic regulation of platelet indices--platelet count, plateletcrit, mean platelet volume, and platelet distribution width--is limited. The association of these platelet indices with a number of biochemical, environmental and clinical variables was studied in a large cohort of the general population. Men and women (n=18,097, 52% women, 56±12 years) were randomly recruited from various villages in Molise (Italy) in the framework of the population-based cohort study "Moli-sani". Hemochromocytometric analyses were performed using an automatic analyzer (Beckman Coulter, IL, Milan, Italy). Associations of platelet indices with dependent variables were investigated by multivariable linear regression analysis. Full models including age, sex, body mass index, blood pressure, smoking, menopause, white and red blood cell counts, mean corpuscular volume, D-dimers, C-reactive protein, high-density lipoproteins, low-density lipoproteins, triglycerides, glucose, and drug use explained 16%, 21%, 1.9% and 4.7% of platelet count, plateletcrit, mean platelet volume and platelet distribution width variability, respectively; variables that appeared to be most strongly associated were white blood cell count, age, and sex. Platelet count, mean platelet volume and plateletcrit were positively associated with white blood cell count, while platelet distribution width was negatively associated with white blood cell count. Platelet count and plateletcrit were also positively associated with C-reactive protein and D-dimers (P<0.0001). Each of the other variables, although associated with platelet indices in a statistically significant manner, only explained less than 0.5% of their variability. Platelet indices varied across Molise villages, independently of any other platelet count determinant or characteristics of the villages. The association of platelet indices with white blood cell count, C-reactive protein and D-dimers in a general population underline the

  15. A prospective cohort study of light transmission platelet aggregometry for bleeding disorders: is testing native platelet-rich plasma non-inferior to testing platelet count adjusted samples?

    PubMed

    Castilloux, Jean Francois; Moffat, Karen A; Liu, Yang; Seecharan, Jodi; Pai, Menaka; Hayward, Catherine P M

    2011-10-01

    Light transmission platelet aggregometry (LTA) is important to diagnose bleeding disorders. Experts recommend testing LTA with native (N) rather than platelet count adjusted (A) platelet-rich plasma (PRP), although it is unclear if this provides non-inferior, or superior, detection of bleeding disorders. Our goal was to determine if LTA with NPRP is non-inferior to LTA with APRP for bleeding disorder assessments. A prospective cohort of patients, referred for bleeding disorder testing, and healthy controls, were evaluated by LTA using common agonists, NPRP and APRP (adjusted to 250 x 10⁹ platelets/l). Recruitment continued until 40 controls and 40 patients with definite bleeding disorders were tested. Maximal aggregation (MA) data were assessed for the detection of abnormalities from bleeding disorders (all causes combined to limit bias), using sample-type specific reference intervals. Areas under receiver-operator curves (AUROC) were evaluated using pre-defined criteria (area differences: < 0.15 for non-inferiority, > 0 for superiority). Forty-four controls and 209 patients were evaluated. Chart reviews for 169 patients indicated 67 had bleeding disorders, 28 from inherited platelet secretion defects. Mean MA differences between NPRP and APRP were small for most agonists (ranges, controls: -3.3 to 5.8; patients: -3.0 to 13.7). With both samples, reduced MA with two or more agonists was associated with a bleeding disorder. AUROC differences between NPRP and APRP were small and indicated that NPRP were non-inferior to APRP for detecting bleeding disorders by LTA, whereas APRP met superiority criteria. Our study validates using either NPRP or APRP for LTA assessments of bleeding disorders.

  16. Estimating leukocyte, platelet, and erythrocyte counts in rats by blood smear examination.

    PubMed

    Durbin, Cathy; Guo, Kevin; Hoffman, Wherly; Eric Schultze, A; White, Sandy

    2009-06-01

    The CBC is an essential test for assessing the health of rats used in drug development studies. Because of limited blood volume, estimates of cell counts from a blood smear would be valuable when other analytical methods of enumerating cells are not possible or available. The purpose of this study was to develop a statistical model to accurately estimate WBC, platelet (PLT), and RBC counts in blood smears from rats. Blood smears and quantitative cell counts were obtained from vehicle-treated male and female Fischer 344 rats (n=65) involved in a variety of studies. The numbers of WBCs, PLTs, and RBCs were estimated in 10 fields in the monolayer of smears using x 20 (WBC) or x 100 (PLT, RBC) objectives. Using a statistical model and the quantitative cell counts obtained on an ADVIA 120 hematology analyzer, formulas were developed to predict the quantitative counts from the estimates. Data were log-transformed before analysis. A formula was derived using the slope and intercept of the regression line between cell estimates and ADVIA counts to predict WBC, PLT, and RBC counts based only on estimates. A second formula was developed for situations in which limited quantitative analyses may be available, and resulted in even more accurately predicted counts from smear estimates. The formulas developed in this study can be a valuable tool in estimating cell counts from a blood smear when cell counting instruments are not available or when an instrument cell count needs to be verified. These formulas may be useful in the assessment of rat blood in discovery and lead optimization studies.

  17. The clinical significance of platelet counts in the first 24 hours after severe injury.

    PubMed

    Stansbury, Lynn G; Hess, Aaron S; Thompson, Kwaku; Kramer, Betsy; Scalea, Thomas M; Hess, John R

    2013-04-01

    Admission platelet (PLT) counts are known to be associated with all-cause mortality for seriously injured patients admitted to a trauma center. The course of subsequent PLT counts, their implications, and the effects of PLT therapy are less well known. Trauma center patients who were directly admitted from the scene of injury, received 1 or more units of uncrossmatched red blood cells in the first hour of care, survived for at least 15 minutes, and had a PLT count measured in the first hour were analyzed for the association of their admission and subsequent PLT counts in the first 24 hours with injury severity and hemorrhagic and central nervous system (CNS) causes of in-hospital mortality. Over an 8.25-year period, 1292 of 45,849 direct trauma admissions met entry criteria. Admission PLT counts averaged 228×10(9) ±90×10(9) /L and decreased by 104×10(9) /L by the second hour and 1×10(9) /L each hour thereafter. The admission count was not related to time to admission. Each 1-point increase in the injury severity score was associated with a 1×10(9) /L decrease in the PLT count at all times in the first 24 hours of care. Admission PLT counts were strongly associated with hemorrhagic and CNS injury mortality and subsequent PLT counts. Effects of PLT therapy could not be ascertained. Admission PLT counts in critically injured trauma patients are usually normal, decreasing after admission. Low PLT counts at admission and during the course of trauma care are strongly associated with mortality. © 2012 American Association of Blood Banks.

  18. Automated three-dimensional detection and counting of neuron somata.

    PubMed

    Oberlaender, Marcel; Dercksen, Vincent J; Egger, Robert; Gensel, Maria; Sakmann, Bert; Hege, Hans-Christian

    2009-05-30

    We present a novel approach for automated detection of neuron somata. A three-step processing pipeline is described on the example of confocal image stacks of NeuN-stained neurons from rat somato-sensory cortex. It results in a set of position landmarks, representing the midpoints of all neuron somata. In the first step, foreground and background pixels are identified, resulting in a binary image. It is based on local thresholding and compensates for imaging and staining artifacts. Once this pre-processing guarantees a standard image quality, clusters of touching neurons are separated in the second step, using a marker-based watershed approach. A model-based algorithm completes the pipeline. It assumes a dominant neuron population with Gaussian distributed volumes within one microscopic field of view. Remaining larger objects are hence split or treated as a second neuron type. A variation of the processing pipeline is presented, showing that our method can also be used for co-localization of neurons in multi-channel images. As an example, we process 2-channel stacks of NeuN-stained somata, labeling all neurons, counterstained with GAD67, labeling GABAergic interneurons, using an adapted pre-processing step for the second channel. The automatically generated landmark sets are compared to manually placed counterparts. A comparison yields that the deviation in landmark position is negligible and that the difference between the numbers of manually and automatically counted neurons is less than 4%. In consequence, this novel approach for neuron counting is a reliable and objective alternative to manual detection.

  19. Platelet Count

    MedlinePlus

    ... also called primary or essential thrombocythemia, a rare myeloproliferative disorder in which the bone marrow produces an ... thrombocythemia have the JAK2 mutation. People with other myeloproliferative or myelodysplastic disorder, such as chronic myeloid leukemia, ...

  20. Platelet count

    MedlinePlus

    ... LE, Heslop HE, Weitz JI, Anastasi J, eds. Hematology: Basic Principles and Practice . 6th ed. Philadelphia, PA: ... 2/7/2017 Updated by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. ...

  1. Platelet count less than SHARP: what does a case series reveal?

    PubMed

    Saif, M Wasif

    2010-01-01

    Hepatocellular carcinoma (HCC) is increasing in numbers worldwide, and no effective systemic treatment existed for advanced HCC until SHARP (Sorafenib in HCC Assessment Randomized Protocol) study proved sorafenib (Nexavar((R)), Bayer Pharmaceuticals, Wayne, NJ, USA) prolonged survival versus placebo. Child-Pugh class A liver function and a platelet count of > or = 60,000/mm(3) were among the inclusion criteria for SHARP. No safety data in patients with < 60,000/mm(3) of platelets are present. Thrombocytopenia is one of the most frequent challenges faced in patients with chronic liver diseases. We report a series of three patients with HCC and platelet count < 60,000/mm(3) who were successfully treated with sorafenib with no complications. We describe the current data on sorafenib and challenges faced in patients with HCC. In addition, we emphasize the need for informed consent when facing factors that predispose to bleeding (esophageal varices, coagulopathy and thrombocytopenia), possible band ligation before the start of sorafenib, careful clinical monitoring and discontinuation of sorafenib when major bleeding occurs.

  2. Pre-treatment platelet counts as a prognostic and predictive factor in stage II and III rectal adenocarcinoma

    PubMed Central

    Steele, Morgan; Voutsadakis, Ioannis A

    2017-01-01

    AIM To investigate if pre-treatment platelet counts could provide prognostic information in patients with rectal adenocarcinoma that received neo-adjuvant treatment. METHODS Platelet number on diagnosis of stage II and III rectal cancer was evaluated in 51 patients receiving neo-adjuvant treatment and for whom there were complete follow-up data on progression and survival, as well as pathologic outcome at the time of surgery. Pathologic responses on the surgical specimen of patients with lower platelet counts (150-300 × 109/L) were compared with these of patients with higher platelet counts (> 300 × 109/L) by the χ2 test. Overall and progression free survival Kaplan-Meier curves of the two groups were constructed and compared with the Log-Rank test. RESULTS A significant difference was present between the two groups in regards to pathologic response with patients with lower platelet counts being more likely to exhibit a good or complete response to neo-adjuvant treatment than patients with higher platelet counts (P = 0.015). Among other factors evaluated, there was also a significant difference between the carcinoembryonic antigen (CEA) at presentation of patients that exhibited a good or complete response and those that had no response or a minimal to moderate response. Patients with a good or complete response were more likely to present with a CEA of less than 5 μg/L (P = 0.00066). There was no significant difference in overall and progression free survival between the two platelet count groups (Log-Rank tests P = 0.42 and P = 0.35, respectively). CONCLUSION In this retrospective analysis of stage II and III rectal cancer patients, platelet counts at the time of diagnosis had prognostic value for neo-adjuvant treatment pathologic response. Pre-treatment CEA also held prognostic value in regards to treatment effect. PMID:28144399

  3. Quality assessment of buffy-coat-derived leucodepleted platelet concentrates in PAS-plasma, prepared by the OrbiSac or TACSI automated system.

    PubMed

    Plaza, E M; Céspedes, P; Fernández, H; Sánchez-Guiu, M I; Egea, J M; Vicente, V; Lozano, M L; Rivera, J

    2014-01-01

    Buffy-coat (BC)-derived platelet concentrates (PCs) are the predominant product for platelet transfusion in many countries. Two automated systems, OrbiSac and TACSI, have been introduced in blood centres to prepare these PCs, as an alternative to the manual method. We compared the in vitro quality of PCs prepared by both methods during standard storage. Twenty primary BC pools were split into two parts, which were processed with OrbiSac and TACSI system to obtain OrbiSac PCs (O-PCs) and TACSI PCs (T-PCs), respectively. On days 1, 5 and 7 of standard storage, samples were taken and the following analysed: cell count, metabolic variables, platelet function and content of activation and proinflammatory substances. Both the OrbiSac and TACSI systems produced PCs that meet the standards for platelet products in terms of platelet and leucocyte content. In vitro evaluation pointed to the similar preservation of platelet metabolism (pH, glucose, bicarbonate and lactate) in O-PCs and T-PCs. Moreover, there were no significant differences between O-PCs and T-PCs as regards the hypotonic shock response or in the platelet aggregation profile. The OrbiSac system caused greater platelet activation, which resulted in higher concentrations of sCD62P, RANTES and sCD40L on the day the PCs were prepared. The systems OrbiSac and TACSI can be used to produce buffy-coat-derived PCs whose cell content, platelet function and metabolism are similar during standard storage. However, the preparation with the OrbiSac system induces a transient increase in platelet activation and release of proinflammatory substances. © 2013 International Society of Blood Transfusion.

  4. Changes in cardiopulmonary variables and platelet count during anesthesia for total hip replacement in dogs.

    PubMed

    Otto, K; Matis, U

    1994-01-01

    Changes in cardiopulmonary function and platelet count were determined in 22 dogs of various breeds that underwent total hip replacement with cemented femoral prostheses. In 11 dogs (group I) polymethylmethacrylate (PMMA) was inserted without venting the reamed and lavaged femoral canal. In a second group of 11 dogs (group II) a urethral catheter (ID: approximately 2.7 mm) was placed into the medullary cavity before the insertion of PMMA. The application of PMMA resulted in a decrease in end-tidal carbon dioxide tension (PETCO2) until 5 minutes after insertion of bone cement. Increases in arterial to end-tidal pCO2 gradient [P(a-ET)CO2] and physiological dead space (VD/VT) were recorded between 2 minutes before and 5 minutes after insertion of PMMA in 12 dogs. A significant decrease in platelet count occurred in both groups of dogs. Decreases in arterial pO2 (PaO2), arterial/alveolar oxygen tension ratio (PaO2/PAO2), and percent O2 saturation of hemoglobin in arterial blood (SaO2) were not statistically significant. No significant differences could be detected between data obtained from both groups of dogs. An increase in femoral intramedullary pressure caused by the insertion of PMMA and subsequent pulmonary microembolism by medullary contents has been considered the most likely cause for changes in pulmonary function. The lack of statistically significant differences in cardiopulmonary variables and platelet count between the two groups of dogs could have been related to inefficient pressure reduction by the method used.

  5. Validity of Particle-Counting Method Using Laser-Light Scattering for Detecting Platelet Aggregation in Diabetic Patients

    NASA Astrophysics Data System (ADS)

    Nakadate, Hiromichi; Sekizuka, Eiichi; Minamitani, Haruyuki

    We aimed to study the validity of a new analytical approach that reflected the phase from platelet activation to the formation of small platelet aggregates. We hoped that this new approach would enable us to use the particle-counting method with laser-light scattering to measure platelet aggregation in healthy controls and in diabetic patients without complications. We measured agonist-induced platelet aggregation for 10 min. Agonist was added to the platelet-rich plasma 1 min after measurement started. We compared the total scattered light intensity from small aggregates over a 10-min period (established analytical approach) and that over a 2-min period from 1 to 3 min after measurement started (new analytical approach). Consequently platelet aggregation in diabetics with HbA1c ≥ 6.5% was significantly greater than in healthy controls by both analytical approaches. However, platelet aggregation in diabetics with HbA1c < 6.5%, i.e. patients in the early stages of diabetes, was significantly greater than in healthy controls only by the new analytical approach, not by the established analytical approach. These results suggest that platelet aggregation as detected by the particle-counting method using laser-light scattering could be applied in clinical examinations by our new analytical approach.

  6. Automated vehicle counting using image processing and machine learning

    NASA Astrophysics Data System (ADS)

    Meany, Sean; Eskew, Edward; Martinez-Castro, Rosana; Jang, Shinae

    2017-04-01

    Vehicle counting is used by the government to improve roadways and the flow of traffic, and by private businesses for purposes such as determining the value of locating a new store in an area. A vehicle count can be performed manually or automatically. Manual counting requires an individual to be on-site and tally the traffic electronically or by hand. However, this can lead to miscounts due to factors such as human error A common form of automatic counting involves pneumatic tubes, but pneumatic tubes disrupt traffic during installation and removal, and can be damaged by passing vehicles. Vehicle counting can also be performed via the use of a camera at the count site recording video of the traffic, with counting being performed manually post-recording or using automatic algorithms. This paper presents a low-cost procedure to perform automatic vehicle counting using remote video cameras with an automatic counting algorithm. The procedure would utilize a Raspberry Pi micro-computer to detect when a car is in a lane, and generate an accurate count of vehicle movements. The method utilized in this paper would use background subtraction to process the images and a machine learning algorithm to provide the count. This method avoids fatigue issues that are encountered in manual video counting and prevents the disruption of roadways that occurs when installing pneumatic tubes

  7. Evaluation of platelet function using the in vitro bleeding time and corrected count increment of transfused platelets. Comparison between platelet concentrates derived from pooled buffy coates and apheresis.

    PubMed

    Eriksson, L; Kristensen, J; Olsson, K; Bring, J; Högman, C F

    1996-01-01

    The functional capacity of transfused platelets was evaluated with in vitro bleeding time (IVBT) and corrected count increment (CCI) in order to compare platelet concentrates (PCs) derived from pooled buffy coats (BC-PCs) with PCs collected by apheresis (A-PCs). The suspension medium in the BC-PCs was 30% CPD plasma and 70% of an additive solution (containing sodium and potassium chloride, sodium citrate and phosphate, mannitol), and in the A-PCs the medium was 100% CPD plasma. IVBT was evaluated using a Thrombostat 4000/2. BC-PC and A-PC were transfused 57 and 41 times, respectively to 36 patients with chemotherapy-induced thrombocytopenia. PCs transfused within 2 days of donation were considered fresh, and those transfused within 3-5 days were considered stored. IVBT was determined before, as well as 10-30 min and 24 h after transfusion; CCI was determined 10-30 min and 24 h after transfusion. The median pretransfusion IVBT value was 486 s. It was measurable in 21 of 98 (21%) of the transfusions, i.e. below the cutoff limit of 486 s. Ten to 30 min after transfusion, the IVBT showed a measurable reduction in 90% of the transfusions with fresh BC-PCs, 92% of those with fresh a-PCs, 63% of those with stored BC-PCs and 79% of those with stored A-PCs. After 24 h, the corresponding values were 63% for fresh BC-PCs, 50% for fresh A-PCs, 26% for stored BC-PCs and 38% for stored A-PCs. The median value of CCI 10-30 min after transfusion was 20 for fresh BC-PCs, 17 for fresh A-PCs, 16 for stored BC-PCs and 14 for stored A-PCs. The difference in IVBT between fresh and stored BC-PCs was significant (p = 0.032), unlike that between fresh and stored A-PC. After 24 h the corresponding values were 7 for fresh BC-PCs, 4 for fresh A-PCs, 4 for stored BC-PCs and 3 for stored A-PCs. When all transfusions with fresh PCs (BC-PCs + A-PCs) were compared with all transfusions with stored PCs, a statistical difference was demonstrated in both CCI (p = 0.027) and IVBT (p = 0.043). Spearman

  8. Effect of Carica papaya Leaf Extract Capsule on Platelet Count in Patients of Dengue Fever with Thrombocytopenia.

    PubMed

    Gadhwal, Ajeet Kumar; Ankit, B S; Chahar, Chitresh; Tantia, Pankaj; Sirohi, P; Agrawal, R P

    2016-06-01

    Thrombocytopenia in dengue fever is a common and serious complication. However, no specific treatment is available for dengue fever induced thrombocytopenia. In few countries (Pakistan, Malaysia, Sri Lanka and other Asian countries) the leaf extract of Carica papaya has been effectively used for thrombocytopenia. So, the study is planned to access effect of Carica papaya leaf extract on platelet count in dengue fever patients. All participants were randomised into two groups, study group and control group; the study group was given papaya leaf extract capsule of 500 mg once daily and routine supportive treatment for consecutive five days. The controls were given only routine supportive treatment. Daily complete blood counts, platelet counts and haematocrit level, liver function test, renal function test of both groups were observed. On the first day platelet count of study group and control group was (59.82±18.63, 61.06±20.03 thousands, p value 0.36). On the 2nd day platelet count of both study and control groups was not significantly different (61.67±19.46 and 59.93±19.52 thousands, p value 0.20) but on 3rd day platelet count of study group was significantly higher than control group (82.96±16.72, 66.45±17.36 thousands, p value < 0.01). On 4th and 5th day platelet count of study group (122.43±19.36 and 112.47±17.49 thousands respectively) was also significantly higher than the control group (88.75±21.65 and 102.59±19.35 thousands) (p value < 0.01). On 7th day platelet count of study group and control group were not significantly different (124.47±12.35 and 122.46±19.76 thousands respectively, p value 0.08). Average hospitalization period of study group v/s control group was 3.65±0.97 v/s 5.42±0.98 days (p value < 0.01). Average platelet transfusion requirement in study group was significantly less than control group (0.685 units per patient v/s 1.19 units per patient) (p value <0.01). It is concluded that Carica papaya leaf extract increases the

  9. Implications of anticoagulants and gender on cell counts and growth factor concentration in platelet-rich plasma and platelet-rich gel supernatants from rabbits.

    PubMed

    González, Juan C; López, Catalina; Carmona, Jorge U

    2016-01-01

    Our objectives were as follows: 1) to validate a protocol for producing rabbit platelet-rich plasma (PRP); 2) to determine the influence of two anticoagulants, sodium citrate and acid-citrate-dextrose solution A, and gender on cell count in PRP and growth factor concentration in pure platelet-rich gel supernatants; 3) to correlate the variables evaluated. Whole blood from 18 New Zealand rabbits (9 males and 9 females) was obtained with sodium citrate and acid-citrate-dextrose solution A for processing PRP fractions (A and B), which were evaluated for haematology. The PRP fractions were either activated with calcium gluconate or lysated with a detergent. The concentrations of transforming growth factor beta 1 and platelet-derived growth factor BB were assayed by ELISA. The sodium citrate PRP-B had significantly higher counts of platelets in comparison to PRP-A and whole blood obtained with the same anticoagulant and the homologous acid-citrate-dextrose solution A PRP fraction. The sodium citrate PRP-A had a significantly higher count of leukocytes compared to the homologous acid-citrate-dextrose solution A fraction. All the PRP fractions had a significant leuko-reduction when compared to whole blood. The sodium citrate PRP-A fraction from female rabbits had significantly lower platelet counts and significantly higher leukocyte counts than the same acid-citrate-dextrose solution A fraction. Growth factor concentration was not affected by the type of anticoagulant or gender. The type of anticoagulant and gender affected the cell counts in PRP, but they did not influence the growth factor concentration. More complete rabbit PRP studies should be performed before evaluating this type of substance in models of disease.

  10. The effect of high altitude on platelet counts, thrombopoietin and erythropoietin levels in young Bolivian airmen visiting the Andes

    NASA Astrophysics Data System (ADS)

    Hudson, J. G.; Bowen, Angela L.; Navia, Pilar; Rios-Dalenz, Jaime; Pollard, Andrew J.; Williams, David; Heath, Donald

    Recognition of thrombosis as a complication of exposure to high altitude has stimulated interest in rheological changes resulting from hypobaric hypoxia. Previous studies of platelet counts at high altitude have yielded conflicting results and have not been studied in conjunction with potential mediating cytokines. We studied the effects of high-altitude exposure on platelet numbers, thrombopoietin (tpo) and erythropoietin (epo) levels in man. A group of 28 volunteers from the Bolivian Airforce stationed at Santa Cruz (600 m altitude) were studied 48 h and 1 week after their ascent to La Paz (3600 m). In addition 105 volunteers based at Santa Cruz for at least 1 year were compared with 175 age- and sex-matched residents at El Alto (4200 m). Platelet counts were measured immediately after sampling and serum samples assayed for tpo and epo. In the ascending group, mean platelet counts were 251×109, 367×109 and 398×109/l at 600 m and following 48 h and 1 week at 3600 m respectively. Mean tpo levels were 132.5, 76 and 92 pg/ml with epo values of 2.98, 11.6 and 7.9 mIU/ml respectively. In the resident populations mean platelet counts were 271×109/l in the low- and 471×109/l in the high-altitude groups. Mean tpo and epo levels measured 69.3 pg/ml and 4.5 mIU/ml respectively at 600 m and 58.5 pg/ml and 5.1 mIU/ml at 4200 m. In conclusion we have demonstrated a significant and sustained elevation in platelet numbers within 48 h of ascent to high altitude. Our findings do not support a role for tpo as a mediator of the increased platelet count. However, these data do not discount epo as a potential candidate.

  11. Pretreatment platelet count as a predictor for survival and distant metastasis in nasopharyngeal carcinoma patients

    PubMed Central

    CHEN, YU-PEI; CHEN, CHEN; MAI, ZHUO-YAO; GAO, JIN; SHEN, LU-JUN; ZHAO, BING-CHENG; CHEN, MENG-KUN; CHEN, GANG; YAN, FANG; HUANG, TONG-YI; XIA, YUN-FEI

    2015-01-01

    The aim of the present study was to investigate the prognostic value of different pretreatment platelet (PLT) counts on the treatment outcome in nasopharyngeal carcinoma (NPC) patients receiving concurrent chemoradiotherapy (CCRT) or radiotherapy (RT) alone. A total of 1,501 NPC patients, including 412 receiving CCRT and 1,089 receiving RT, were enrolled in the present study. The PLT count cut-off points for the CCRT and RT groups were 150 and 300×109/l, respectively, and the PLT counts were categorized it into three groups: Low (PLT≤150×109/l), moderate (150×109/l300×109/l). To identify independent predictors of overall survival (OS), the Cox proportional hazards model was used to determine local-regional recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) rates in the CCRT and RT patients. Furthermore, univariate and multivariate analysis indicated that compared with a moderate PLT count, a low PLT count was an independent unfavorable prognostic factor for OS rate in CCRT patients [hazard ratio (HR), 2.024; 95% confidence interval (CI), 1.165–3.516], and a high PLT count was an independent unfavorable prognostic factor for OS and DMFS rates in CCRT (OS: HR, 1.742; 95% CI, 1.090–2.786; DFMS: HR, 2.110; 95%CI, 1.084–4.108) and RT (OS: HR, 1.740; 95%CI, 1.283–2.362; DMFS: HR, 2.819; 95% CI, 1.766–4.497) patients. Compared with a low PLT count, a high PLT count was significantly and independently associated with a poor DMFS rate in the RT patients (P=0.025; HR, 2.454; 95% CI, 1.121–5.372). Therefore, the present study indicates that low and high PLT counts may be useful indicators of survival and distant metastasis in NPC patients who have undergone radiation treatment. PMID:25663931

  12. The evaluation of sequential platelet counts has prognostic value for acute kidney injury patients requiring dialysis in the intensive care setting

    PubMed Central

    Valente, Carla; Soares, Márcio; Rocha, Eduardo; Cardoso, Lucio; Maccariello, Elizabeth

    2013-01-01

    OBJECTIVE: To evaluate the prognostic value of platelet counts in acute kidney injury patients requiring renal replacement therapy. METHODS: This prospective cohort study was performed in three tertiary-care hospitals. Platelet counts were obtained upon admission to the intensive care unit and during the first week of renal replacement therapy on days 1, 3, 5 and 7. The outcome of interest was the hospital mortality rate. With the aim of minimizing individual variation, we analyzed the relative platelet counts on days 3, 5, 7 and at the point of the largest variation during the first week of renal replacement therapy. Logistic regression analysis was used to test the prognostic value of the platelet counts. RESULTS: The study included 274 patients. The hospital mortality rate was 62%. The survivors had significantly higher platelet counts upon admission to the intensive care unit compared to the non-survivors [175.5×103/mm3 (108.5–259×103/mm3) vs. 148×103/mm3 (80−141×103/mm3)] and during the first week of renal replacement therapy. The relative platelet count reductions were significantly associated with a higher hospital mortality rate compared with the platelet count increases (70% vs. 44% at the nadir, respectively). A relative platelet count reduction >60% was significantly associated with a worse outcome (mortality rate = 82.6%). Relative platelet count variations and the percentage of reduction were independent risk factors of hospital mortality during the first week of renal replacement therapy. CONCLUSION: Platelet counts upon admission to the intensive care unit and at the beginning of renal replacement therapy as well as sequential platelet count evaluation have prognostic value in acute kidney injury patients requiring renal replacement therapy. PMID:23778497

  13. Development of an automated asbestos counting software based on fluorescence microscopy.

    PubMed

    Alexandrov, Maxym; Ichida, Etsuko; Nishimura, Tomoki; Aoki, Kousuke; Ishida, Takenori; Hirota, Ryuichi; Ikeda, Takeshi; Kawasaki, Tetsuo; Kuroda, Akio

    2015-01-01

    An emerging alternative to the commonly used analytical methods for asbestos analysis is fluorescence microscopy (FM), which relies on highly specific asbestos-binding probes to distinguish asbestos from interfering non-asbestos fibers. However, all types of microscopic asbestos analysis require laborious examination of large number of fields of view and are prone to subjective errors and large variability between asbestos counts by different analysts and laboratories. A possible solution to these problems is automated counting of asbestos fibers by image analysis software, which would lower the cost and increase the reliability of asbestos testing. This study seeks to develop a fiber recognition and counting software for FM-based asbestos analysis. We discuss the main features of the developed software and the results of its testing. Software testing showed good correlation between automated and manual counts for the samples with medium and high fiber concentrations. At low fiber concentrations, the automated counts were less accurate, leading us to implement correction mode for automated counts. While the full automation of asbestos analysis would require further improvements in accuracy of fiber identification, the developed software could already assist professional asbestos analysts and record detailed fiber dimensions for the use in epidemiological research.

  14. Microscopic images dataset for automation of RBCs counting.

    PubMed

    Abbas, Sherif

    2015-12-01

    A method for Red Blood Corpuscles (RBCs) counting has been developed using RBCs light microscopic images and Matlab algorithm. The Dataset consists of Red Blood Corpuscles (RBCs) images and there RBCs segmented images. A detailed description using flow chart is given in order to show how to produce RBCs mask. The RBCs mask was used to count the number of RBCs in the blood smear image.

  15. Microscopic images dataset for automation of RBCs counting

    PubMed Central

    Abbas, Sherif

    2015-01-01

    A method for Red Blood Corpuscles (RBCs) counting has been developed using RBCs light microscopic images and Matlab algorithm. The Dataset consists of Red Blood Corpuscles (RBCs) images and there RBCs segmented images. A detailed description using flow chart is given in order to show how to produce RBCs mask. The RBCs mask was used to count the number of RBCs in the blood smear image. PMID:26380843

  16. OPTIMIZATION OF A FILTER-LYSIS PROTOCOL TO PURIFY RAT TESTICULAR HOMOGENATES FOR AUTOMATED SPERMATID COUNTING

    PubMed Central

    Pacheco, Sara E.; Anderson, Linnea M.; Boekelheide, Kim

    2013-01-01

    Objectives Quantifying testicular homogenization resistant spermatid heads (HRSH) is a powerful indicator of spermatogenesis. These counts have traditionally been performed manually using a hemocytometer, but this method can be time consuming and biased. We aimed to develop a protocol to reduce debris for the application of automated counting, which would allow for efficient and unbiased quantification of rat HRSH. Findings We developed a filter-lysis protocol that effectively removes debris from rat testicular homogenates. After filtering and lysing the homogenates, we found no statistical differences between manual (classic and filter-lysis) and automated (filter-lysis) counts using one-way ANOVA with Bonferroni’s multiple comparison test. In addition, Pearson’s correlation coefficients were calculated to compare the counting methods and there was a strong correlation between the classic manual counts and the filter-lysis manual (r = 0.85, p = 0.002) and the filter-lysis automated (r = 0.89, p = 0.0005) counts. We also tested the utility of the automated method in a low dose exposure model known to decrease HRSH. Adult Fischer 344 rats exposed to 0.33% 2,5-hexanedione (HD) in the drinking water for 12 weeks demonstrated decreased body (p = 0.02) and testes (p = 0.002) weights. In addition, there was a significant reduction in the number of HRSH per testis (p = 0.002) when compared to control. Conclusions A filter-lysis protocol was optimized to purify rat testicular homogenates for automated HRSH counts. Automated counting systems yield unbiased data and can be applied to detect changes in the testis after low dose toxicant exposure. PMID:22240558

  17. Bone marrow adsorbed dose of rhenium-186-HEDP and the relationship with decreased platelet counts

    SciTech Connect

    Klerk, J.M.H. de; Dieren, E.B. van; Schip, A.D. van het

    1996-01-01

    Rhenium-186(Sn)-1,1-hydroxyethylidene diphosphonate ({sup 186}Re-HEDP) has been used for palliation of metastatic bone pain. The purpose of this study was to find a relationship between the bone marrow absorbed dose and the toxicity, expressed as the percentage decrease in the peripheral blood platelet count. The bone marrow absorbed dose was calculated according to the MIRD model using data obtained from ten treatments of patients suffering from metastatic prostate cancer; noninvasive and pharmacokinetic method were used. The bone marrow doses were related to toxicity using the pharmacodynamic sigmoid E{sub max} model. The mean bone marrow absorbed doses using the noninvasive and pharmacokinetic methods were in a close range to each other (1.07 mGy/MBq and 1.02 mGy/MBq, respectively). There was a good relationship between the toxicity and the bone marrow absorbed dose (r = 0.80). Furthermore, the EDrm{sub 50} (i.e., the bone marrow absorbed dose producing a 50% platelet decrease) to bone marrow for {sup 186}Re-HEDP was on the order of 2 Gy. Although the function of normal bone marrow is affected by metastases in patients with metastatic bone disease, the MIRD model can be used to relate toxicity to the bone marrow absorbed dose after a therapeutic dosage of {sup 186}Re-HEDP. 33 refs., 1 fig., 1 tab.

  18. Assessment of the Effects of 2'-Methoxyethyl Antisense Oligonucleotides on Platelet Count in Cynomolgus Nonhuman Primates.

    PubMed

    Henry, Scott P; Narayanan, Padmakumar; Shen, Lijiang; Bhanot, Sanjay; Younis, Husam S; Burel, Sebastien A

    2017-08-01

    Decreases in platelet (PLT) counts observed in nonhuman primates (NHPs) given 2'-O-methoxyethyl modified antisense inhibitors (2'-MOE ASOs) have been reported, but the incidence and severity of the change vary considerably between sequences, studies, and animals. This article will broadly illustrate the spectrum of effects on PLT count in NHPs. From queries of an NHP safety database representing over 102 independent 2'-MOE ASOs, from 61 studies and >2200 NHPs, two patterns of PLT changes emerged. The first is a consistent and reproducible decrease in group mean values, observed with about 30% of the compounds, in which PLT count typically remains ≥150K cells/μL. The second is a sporadic decrease in PLTs to <50K cells/μL (2%-4% incidence at doses >5 mg/kg) that is often not reproducible. In both cases, the reduction in PLT count is dose dependent and reversible. The human relevance of PLT change observed in NHPs was investigated using ISIS 404173. In a chronic NHP study (20 mg/kg/wk for 26 weeks), a gradual decrease in group mean PLT count was observed at ≥10 mg/kg/wk, which plateaued by 13 weeks generally within the normal range and was maintained through 26 weeks of treatment. However, PLT counts <50K cells/μL occurred in 1 of 16 NHP at 10 mg/kg/wk and 3 of 16 NHP at 20 mg/kg/wk. In a 26-week double-blind, placebo-controlled Phase 2 trial, 62 patients were treated with 200 mg/wk ISIS 404173 (∼3.3 mg/kg/wk) there was an increased incidence of PLT count >30% decreased compared to baseline but no incidence of PLT <75K cells/μL. Based on these data, the consistent, self-limiting PLT reduction seen in NHP may translate to humans, but these changes appear to be of limited clinical significance. However, NHPs appear to overpredict the incidence of sporadic PLT <50K cells/μL compared to humans.

  19. The SH2B3 and KCNK5 loci may be implicated in regulation of platelet count, volume, and maturity.

    PubMed

    Christiansen, Morten K; Larsen, Sanne B; Nyegaard, Mette; Neergaard-Petersen, Søs; Würtz, Morten; Grove, Erik L; Hvas, Anne-Mette; Jensen, Henrik K; Kristensen, Steen D

    2017-08-18

    In recent genome-wide association studies, coronary artery disease (CAD) and myocardial infarction (MI) have been linked to a number of genetic variants, but their role in thrombopoiesis is largely unknown. We investigated the association between CAD and MI-associated genetic variants and five thrombopoiesis-related indices: platelet count (PC), mean platelet volume (MPV), immature platelet count (IPC), immature platelet fraction (IPF), and serum thrombopoietin (TPO). We genotyped 45 genome-wide significant CAD/MI-markers in 879 stable CAD patients. A genetic risk score was calculated to assess the combined risk associated with all the genetic variants. Platelet indices were analysed using the Sysmex XE-2100 haematology analyser. TPO was measured by ELISA. Two variants were nominally associated with several indices; for rs10947789 (KCNK5), the adjusted geometric mean was 2% higher for MPV (95% confidence interval: 1-2%, p=0.002), 6% for IPC (0-12%, p=0.033), and 9% for IPF (3-16%, p=0.004) per CAD risk allele. Moreover, an 11% lower TPO (3-19%, p=0.010) was observed. Rs3184504 (SH2B3) was associated with a higher adjusted geometric mean of 3% (1-6%, p=0.003) per CAD risk allele for PC, and an 11% (5-17%, p<0.001) lower TPO. Furthermore, the adjusted IPC was 5% (0-9%, p=0.037) lower per CAD risk allele for PC, whereas IPF levels did not vary across genotypes. As a novel finding, our study suggests a role for KCNK5 in the regulation of platelet size and maturity. Furthermore, our findings confirm an association between the SH2B3-locus and platelet count. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Reduced platelet count, but no major platelet function abnormalities, are associated with loss-of-function ATP-binding cassette-1 gene mutations.

    PubMed

    Minuz, Pietro; Meneguzzi, Alessandra; Femia, Eti Alessandra; Fava, Cristiano; Calabria, Stefano; Scavone, Mariangela; Benati, Donatella; Poli, Giovanni; Zancanaro, Carlo; Calandra, Sebastiano; Lucchi, Tiziano; Cattaneo, Marco

    2017-08-15

    Loss-of-function mutations of the the ATP-binding cassette-1 (ABCA1) gene are the cause of Tangier disease (TD) in homozygous subjects and familial HDL deficiency (FHD) in heterozygous subjects. These disorders are characterized by reduced plasma HDL-cholesterol (HDL-C) and altered efflux of cholesterol from cells. Previous studies in TD patients and ABCA1(-/-) murine models reported defects in platelet count, morphology, and function, but the issue is still controversial. We analyzed three subjects with low to very low HDL-C levels due to the loss-of-function mutations of the ABCA1 gene. Two related patients with FHD were heterozygous carriers of two mutations on the same ABCA1 allele; one, with TD, was homozygous for a different mutation. Mild to moderate thrombocytopenia was observed in all the patients. No morphological platelet abnormalities were detected under optical or EM. History of moderate bleeding tendency was recorded only in one of the FHD patients. Only limited alterations in platelet aggregation and activation of the integrin αIIbβ3 were observed in one FHD patient. While α-granule secretion (P-selectin), content, and secretion of platelet δ-granules (serotonin, ATP, and ADP) and thromboxane (TX) A2 synthesis were normal in all the patients, the expression of lysosomal CD63, in response to some agonists, was reduced in TD patients. In conclusion, three patients carrying ABCA1 genetic variants had low platelet count, with the lowest values observed in TD, not associated with major alterations in platelet morphology and response to agonists or bleeding. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  1. Automating Partial Period Bond Valuation with Excel's Day Counting Functions

    ERIC Educational Resources Information Center

    Vicknair, David; Spruell, James

    2009-01-01

    An Excel model for calculating the actual price of bonds under a 30 day/month, 360 day/year day counting assumption by nesting the DAYS360 function within the PV function is developed. When programmed into an Excel spreadsheet, the model can accommodate annual and semiannual payment bonds sold on or between interest dates using six fundamental…

  2. Automating Partial Period Bond Valuation with Excel's Day Counting Functions

    ERIC Educational Resources Information Center

    Vicknair, David; Spruell, James

    2009-01-01

    An Excel model for calculating the actual price of bonds under a 30 day/month, 360 day/year day counting assumption by nesting the DAYS360 function within the PV function is developed. When programmed into an Excel spreadsheet, the model can accommodate annual and semiannual payment bonds sold on or between interest dates using six fundamental…

  3. Platelets

    MedlinePlus

    ... common disorder of platelet function is caused by aspirin. Aspirin blocks one of the steps required for platelets to stick together. This effect of aspirin is what makes it an effective treatment for ...

  4. Under-filled blood collection tubes containing K2EDTA as anticoagulant are acceptable for automated complete blood counts, white blood cell differential, and reticulocyte count.

    PubMed

    Xu, M; Robbe, V A; Jack, R M; Rutledge, J C

    2010-10-01

    Current laboratory standards from Clinical Laboratory Standards Institute (CLSI) and manufacturer's (Becton Dickinson) data indicate that under-filling K(2)EDTA blood collection tubes can result in erroneous hematology values. To accommodate under-filled tubes and reduce collection volumes while optimizing our automation, we explored the acceptable limit of under-filled tubes for hematology values. We collected 8.0 ml of blood from 30 normal adult volunteers. Each donation was aliquoted in the following volumes: 4.0, 2.0, 1.0, 0.5 ml x 2. These samples were analyzed within 1 h of blood collection on Sysmex XE-2100 (Sysmex America Inc., Mundelein, IL, USA) for complete blood count, reticulocyte, and white blood cell differentials. Results of the under-filled tubes were compared to those of the standard volume. The Deming regression analysis show excellent correlation for all parameters between each under-filled blood collection volume compared to a standard 4 ml volume. The Bland and Altman analysis shows good agreement between both 1.0 and 2.0 ml compared to a 4.0 ml volume. The 0.5 ml compared to a 4.0 ml volume, however, shows increased variation on many parameters. In addition all three collection volumes show negative bias compared to the standard volume for platelet count, but the difference is considered insignificant with a percent difference of 5.5%, 3.2%, and 1.5% for 0.5, 1.0, and 2.0 ml collection volume respectively. Finally for 0.5 ml collection volume we noticed a low level of false positive flagging rate for white blood cell. Acceptable complete blood count values of under-filled powdered K(2)EDTA tubes can be obtained with as little as 1.0 ml of blood.

  5. 21 CFR 864.5200 - Automated cell counter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated cell counter. 864.5200 Section 864.5200....5200 Automated cell counter. (a) Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the...

  6. 21 CFR 864.5200 - Automated cell counter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated cell counter. 864.5200 Section 864.5200....5200 Automated cell counter. (a) Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the...

  7. 21 CFR 864.5200 - Automated cell counter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated cell counter. 864.5200 Section 864.5200....5200 Automated cell counter. (a) Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the...

  8. 21 CFR 864.5200 - Automated cell counter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated cell counter. 864.5200 Section 864.5200....5200 Automated cell counter. (a) Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the...

  9. An image-processing program for automated counting

    USGS Publications Warehouse

    Cunningham, D.J.; Anderson, W.H.; Anthony, R.M.

    1996-01-01

    An image-processing program developed by the National Institute of Health, IMAGE, was modified in a cooperative project between remote sensing specialists at the Ohio State University Center for Mapping and scientists at the Alaska Science Center to facilitate estimating numbers of black brant (Branta bernicla nigricans) in flocks at Izembek National Wildlife Refuge. The modified program, DUCK HUNT, runs on Apple computers. Modifications provide users with a pull down menu that optimizes image quality; identifies objects of interest (e.g., brant) by spectral, morphometric, and spatial parameters defined interactively by users; counts and labels objects of interest; and produces summary tables. Images from digitized photography, videography, and high- resolution digital photography have been used with this program to count various species of waterfowl.

  10. Influence of centrifuge brake on residual platelet count and routine coagulation tests in citrated plasma.

    PubMed

    Daves, Massimo; Giacomuzzi, Katia; Tagnin, Enrico; Jani, Erika; Adcock Funk, Dorothy M; Favaloro, Emmanuel J; Lippi, Giuseppe

    2014-04-01

    Sample centrifugation is an essential step in the coagulation laboratory, as clotting tests are typically performed on citrated platelet (PLT) poor plasma (PPP). Nevertheless, no clear indication has been provided as to whether centrifugation of specimens should be performed with the centrifuge brake set to on or off. Fifty consecutive sodium citrate anticoagulated samples were collected and divided into two aliquots. The former was centrifuged as for Clinical Laboratory Standards Institute (CLSI) guidelines with the centrifuge brake set to on, whereas the latter was centrifuged again as for CLSI guidelines, but with the brake set to off. In the PPP of all samples, a PLT count was performed, followed by the analysis of activated partial thromboplastin time (APTT), prothrombin time (PT) and fibrinogen (FBG). The PLT count after samples centrifugation was substantially reduced, either with centrifuge brake set to on or off (5 ± 1 versus 3 ± 1 × 10/l; P = 0.009). The frequency of samples exceeding a PLT count less than 10 × 10/l was nearly double in samples centrifuged with the brake on than in those with the brake off (14 versus 8%; P < 0.01). Although no significant difference was found for APTT values, PT was slightly prolonged using the centrifuge brake set to on (mean bias 0.2 s; P < 0.001). FBG values were also significantly higher using the centrifuge brake set to on (mean bias 0.29 g/l; P < 0.001). The results of this study indicate that sample centrifugation for routine coagulation testing should be preferably performed with the centrifuge brake set to off for providing a better quality specimen.

  11. Application of a non-hazardous vital dye for cell counting with automated cell counters.

    PubMed

    Kim, Soo In; Kim, Hyun Jeong; Lee, Ho-Jae; Lee, Kiwon; Hong, Dongpyo; Lim, Hyunchang; Cho, Keunchang; Jung, Neoncheol; Yi, Yong Weon

    2016-01-01

    Recent advances in automated cell counters enable us to count cells more easily with consistency. However, the wide use of the traditional vital dye trypan blue (TB) raises environmental and health concerns due to its potential teratogenic effects. To avoid this chemical hazard, it is of importance to introduce an alternative non-hazardous vital dye that is compatible with automated cell counters. Erythrosin B (EB) is a vital dye that is impermeable to biological membranes and is used as a food additive. Similarly to TB, EB stains only nonviable cells with disintegrated membranes. However, EB is less popular than TB and is seldom used with automated cell counters. We found that cell counting accuracy with EB was comparable to that with TB. EB was found to be an effective dye for accurate counting of cells with different viabilities across three different automated cell counters. In contrast to TB, EB was less toxic to cultured HL-60 cells during the cell counting process. These results indicate that replacing TB with EB for use with automated cell counters will significantly reduce the hazardous risk while producing comparable results.

  12. Assessing Rotation-Invariant Feature Classification for Automated Wildebeest Population Counts.

    PubMed

    Torney, Colin J; Dobson, Andrew P; Borner, Felix; Lloyd-Jones, David J; Moyer, David; Maliti, Honori T; Mwita, Machoke; Fredrick, Howard; Borner, Markus; Hopcraft, J Grant C

    2016-01-01

    Accurate and on-demand animal population counts are the holy grail for wildlife conservation organizations throughout the world because they enable fast and responsive adaptive management policies. While the collection of image data from camera traps, satellites, and manned or unmanned aircraft has advanced significantly, the detection and identification of animals within images remains a major bottleneck since counting is primarily conducted by dedicated enumerators or citizen scientists. Recent developments in the field of computer vision suggest a potential resolution to this issue through the use of rotation-invariant object descriptors combined with machine learning algorithms. Here we implement an algorithm to detect and count wildebeest from aerial images collected in the Serengeti National Park in 2009 as part of the biennial wildebeest count. We find that the per image error rates are greater than, but comparable to, two separate human counts. For the total count, the algorithm is more accurate than both manual counts, suggesting that human counters have a tendency to systematically over or under count images. While the accuracy of the algorithm is not yet at an acceptable level for fully automatic counts, our results show this method is a promising avenue for further research and we highlight specific areas where future research should focus in order to develop fast and accurate enumeration of aerial count data. If combined with a bespoke image collection protocol, this approach may yield a fully automated wildebeest count in the near future.

  13. Assessing Rotation-Invariant Feature Classification for Automated Wildebeest Population Counts

    PubMed Central

    Torney, Colin J.; Dobson, Andrew P.; Borner, Felix; Lloyd-Jones, David J.; Moyer, David; Maliti, Honori T.; Mwita, Machoke; Fredrick, Howard; Borner, Markus; Hopcraft, J. Grant C.

    2016-01-01

    Accurate and on-demand animal population counts are the holy grail for wildlife conservation organizations throughout the world because they enable fast and responsive adaptive management policies. While the collection of image data from camera traps, satellites, and manned or unmanned aircraft has advanced significantly, the detection and identification of animals within images remains a major bottleneck since counting is primarily conducted by dedicated enumerators or citizen scientists. Recent developments in the field of computer vision suggest a potential resolution to this issue through the use of rotation-invariant object descriptors combined with machine learning algorithms. Here we implement an algorithm to detect and count wildebeest from aerial images collected in the Serengeti National Park in 2009 as part of the biennial wildebeest count. We find that the per image error rates are greater than, but comparable to, two separate human counts. For the total count, the algorithm is more accurate than both manual counts, suggesting that human counters have a tendency to systematically over or under count images. While the accuracy of the algorithm is not yet at an acceptable level for fully automatic counts, our results show this method is a promising avenue for further research and we highlight specific areas where future research should focus in order to develop fast and accurate enumeration of aerial count data. If combined with a bespoke image collection protocol, this approach may yield a fully automated wildebeest count in the near future. PMID:27227888

  14. Red Blood Cell Distribution Width and the Platelet Count in Iron-deficient Children Aged 0.5-3 Years.

    PubMed

    Akkermans, M D; Uijterschout, L; Vloemans, J; Teunisse, P P; Hudig, F; Bubbers, S; Verbruggen, S; Veldhorst, M; de Leeuw, T G; van Goudoever, J B; Brus, F

    2015-01-01

    Early detection of iron deficiency (ID) and iron deficiency anemia (IDA) in young children is important to prevent impaired neurodevelopment. Unfortunately, many biomarkers of ID are influenced by infection, thus limiting their usefulness. The aim of this study was to investigate the value of red blood cell distribution width (RDW) and the platelet count for detecting ID(A) among otherwise healthy children. A multicenter prospective observational study was conducted in the Netherlands to investigate the prevalence of ID(A) in 400 healthy children aged 0.5-3 years. ID was defined as serum ferritin (SF) <12 μg/L in the absence of infection (C-reactive protein [CRP] <5 mg/L) and IDA as hemoglobin <110 g/L combined with ID. RDW (%) and the platelet count were determined in the complete blood cell count. RDW was inversely correlated with SF and not associated with CRP. Calculated cutoff values for RDW to detect ID and IDA gave a relatively low sensitivity (53.1% and 57.1%, respectively) and specificity (64.7% and 69.9%, respectively). Anemic children with a RDW >14.3% had a 2.7 higher odds (95% confidence interval [CI]: 1.2-6.3) to be iron deficient, compared with anemic children with a RDW <14.3%. The platelet count showed a large range in both ID and non-ID children. In conclusion, RDW can be helpful for identifying ID as the cause of anemia in 0.5- to 3-year-old children, but not as primary biomarker of ID(A). RDW values are not influenced by the presence of infection. There appears to be no role for the platelet count in diagnosing ID(A) in this group of children.

  15. Platelet Count in First Trimester of Pregnancy as a Predictor of Perinatal Outcome

    PubMed Central

    Larroca, Santiago Garcia-Tizon; Arevalo-Serrano, Juan; Abad, Virginia Ortega; Recarte, Pilar Pintado; Carreras, Alejandro Garcia; Pastor, Gonzalo Nozaleda; Hernandez, Cesar Rodriguez; Pacheco, Ricardo Perez Fernandez; Luis, Juan De Leon

    2017-01-01

    AIM: To rule out maternal and pregnancy factors that may contribute to platelet count (PLT) changes in the first trimester of gestation and examine if there is any association between its levels and adverse perinatal outcome. METHODS: The study population included all patients from the first-trimester visit between 2013-2015 with pregnancy results. Linear multiple regression was constructed to rule out variables that may have a significant contribution to PLT. For each adverse outcome at birth, multiple logistic regression analysis was implemented to estimate the PLT effect. RESULTS: PLT was measured in 6092 patients. There was the significant contribution on PLT in the first trimester from maternal weight, the presence of rheumatologic disease, BHCG levels and MPV. There was a significant association between PLT and abnormal cardiotocography at delivery (OR 1.004; IC95% 1.001 to 1.007) and C-Section due to abnormal CTG (OR 1.005; IC95% 1.002 to 1.008). When adjusted for factors that interact with PLT there was also a significant association with pH at birth < 7.10 and gestational diabetes. CONCLUSIONS: Maternal and pregnancy factors can poorly predict relevant changes in PLT at the first trimester of gestation. PLT at first trimester of pregnancy might predict adverse perinatal outcome in combination with other markers. PMID:28293312

  16. Platelet Count Measured Prior to Cancer Development Is a Risk Factor for Future Symptomatic Venous Thromboembolism: The Tromsø Study

    PubMed Central

    Jensvoll, Hilde; Blix, Kristine; Brækkan, Sigrid K.; Hansen, John-Bjarne

    2014-01-01

    Background Elevated platelet count is associated with risk of venous thromboembolism in cancer patients initiating chemotherapy. It is not known whether this risk by platelet count is causal or merely reflects the malignant disease. We investigated whether pre-cancer platelet count alone or together with high leukocyte count was associated with risk of venous thromboembolism in subjects who did and did not develop cancer during follow-up in a population-based cohort study. Methods Platelet count and other baseline characteristics were measured in 25160 initially cancer-free subjects who participated in the Tromsø Study in 1994–1995. Incident cancer and symptomatic venous thromboembolism events were registered up to December 31st, 2009. Multivariable Cox regression models were used to calculate hazard ratio for venous thromboembolism across categories of platelet count (<40th, 40–80th, and >80th percentile) with 95% confidence interval. Results During follow-up, 2082 subjects were diagnosed with cancer. Platelet count was measured on average 8.3 years before the cancer diagnosis. There were 129 venous thromboembolism events in the cancer cohort (13.5 per 1000 person-years) and 377 in the non-cancer cohort (1.2 per 1000 person-years). In cancer patients, pre-cancer platelet count above the 80th percentile (≥295×109/L) was associated with a 2-fold higher risk of venous thromboembolism (Hazard ratio: 1.98, 95% confidence interval 1.21–3.23) compared to platelet count below the 40th percentile (<235×109/L). Concomitant high platelet and leukocyte counts showed a synergistic effect on the VTE risk. In cancer-free subjects, no association was found. Comment In conclusion, pre-cancer platelet count was associated with risk of symptomatic venous thromboembolism in cancer patients, but not in cancer-free subjects. Our findings suggest that platelet count and platelet-leukocyte interactions may play a role in the pathogenesis of cancer-related venous

  17. Platelet count measured prior to cancer development is a risk factor for future symptomatic venous thromboembolism: the Tromsø Study.

    PubMed

    Jensvoll, Hilde; Blix, Kristine; Brækkan, Sigrid K; Hansen, John-Bjarne

    2014-01-01

    Elevated platelet count is associated with risk of venous thromboembolism in cancer patients initiating chemotherapy. It is not known whether this risk by platelet count is causal or merely reflects the malignant disease. We investigated whether pre-cancer platelet count alone or together with high leukocyte count was associated with risk of venous thromboembolism in subjects who did and did not develop cancer during follow-up in a population-based cohort study. Platelet count and other baseline characteristics were measured in 25160 initially cancer-free subjects who participated in the Tromsø Study in 1994-1995. Incident cancer and symptomatic venous thromboembolism events were registered up to December 31st, 2009. Multivariable Cox regression models were used to calculate hazard ratio for venous thromboembolism across categories of platelet count (<40th, 40-80th, and >80th percentile) with 95% confidence interval. During follow-up, 2082 subjects were diagnosed with cancer. Platelet count was measured on average 8.3 years before the cancer diagnosis. There were 129 venous thromboembolism events in the cancer cohort (13.5 per 1000 person-years) and 377 in the non-cancer cohort (1.2 per 1000 person-years). In cancer patients, pre-cancer platelet count above the 80th percentile (≥295×10(9)/L) was associated with a 2-fold higher risk of venous thromboembolism (Hazard ratio: 1.98, 95% confidence interval 1.21-3.23) compared to platelet count below the 40th percentile (<235×10(9)/L). Concomitant high platelet and leukocyte counts showed a synergistic effect on the VTE risk. In cancer-free subjects, no association was found. In conclusion, pre-cancer platelet count was associated with risk of symptomatic venous thromboembolism in cancer patients, but not in cancer-free subjects. Our findings suggest that platelet count and platelet-leukocyte interactions may play a role in the pathogenesis of cancer-related venous thromboembolism.

  18. A semi-automated technique for labeling and counting of apoptosing retinal cells

    PubMed Central

    2014-01-01

    Background Retinal ganglion cell (RGC) loss is one of the earliest and most important cellular changes in glaucoma. The DARC (Detection of Apoptosing Retinal Cells) technology enables in vivo real-time non-invasive imaging of single apoptosing retinal cells in animal models of glaucoma and Alzheimer’s disease. To date, apoptosing RGCs imaged using DARC have been counted manually. This is time-consuming, labour-intensive, vulnerable to bias, and has considerable inter- and intra-operator variability. Results A semi-automated algorithm was developed which enabled automated identification of apoptosing RGCs labeled with fluorescent Annexin-5 on DARC images. Automated analysis included a pre-processing stage involving local-luminance and local-contrast “gain control”, a “blob analysis” step to differentiate between cells, vessels and noise, and a method to exclude non-cell structures using specific combined ‘size’ and ‘aspect’ ratio criteria. Apoptosing retinal cells were counted by 3 masked operators, generating ‘Gold-standard’ mean manual cell counts, and were also counted using the newly developed automated algorithm. Comparison between automated cell counts and the mean manual cell counts on 66 DARC images showed significant correlation between the two methods (Pearson’s correlation coefficient 0.978 (p < 0.001), R Squared = 0.956. The Intraclass correlation coefficient was 0.986 (95% CI 0.977-0.991, p < 0.001), and Cronbach’s alpha measure of consistency = 0.986, confirming excellent correlation and consistency. No significant difference (p = 0.922, 95% CI: −5.53 to 6.10) was detected between the cell counts of the two methods. Conclusions The novel automated algorithm enabled accurate quantification of apoptosing RGCs that is highly comparable to manual counting, and appears to minimise operator-bias, whilst being both fast and reproducible. This may prove to be a valuable method of quantifying apoptosing retinal

  19. Adherence to the Mediterranean diet is associated with lower platelet and leukocyte counts: results from the Moli-sani study.

    PubMed

    Bonaccio, Marialaura; Di Castelnuovo, Augusto; De Curtis, Amalia; Costanzo, Simona; Persichillo, Mariarosaria; Donati, Maria Benedetta; Cerletti, Chiara; Iacoviello, Licia; de Gaetano, Giovanni

    2014-05-08

    Platelet (PLT) and white blood cell (WBC) counts are 2 markers of inflammation and have been linked to the risk for cerebrovascular and coronary heart disease. A Mediterranean diet (MD) has been associated with reduced inflammation and mortality for major chronic diseases. We aimed at evaluating the association between the MD and both PLT and WBC counts. This cross-sectional analysis in a population-based cohort study included 14,586 healthy Italian citizens enrolled within the Moli-sani study. Adherence to MD was appraised by either the MD Score (MDS) or the Italian Mediterranean Index (IMI). PLT and WBC counts were both inversely related to MD adherence (MDS: P < .0001 and P = .008, respectively). As compared with those with poorer MD adherence, subjects with greater adherence had both reduced odds of being in the highest PLT-count group (MDS: odds ratio = 0.50; 95% confidence interval, 0.31-0.80) and increased odds of being in the lowest WBC-count group (IMI: odds ratio = 1.41; 95% confidence interval, 1.07-1.86). The association between WBC count and MDS disappeared when further adjusted for PLT count, whereas the association between PLT count and the MD was not affected by adjustment for WBCs. Food antioxidant and dietary fiber content modified the inverse association between MDS and WBC count and partially accounted for the association with PLTs.

  20. A Comparison of Automated and Manual Crater Counting Techniques in Images of Elysium Planitia.

    NASA Astrophysics Data System (ADS)

    Plesko, C. S.; Brumby, S. P.; Asphaug, E.

    2004-11-01

    Surveys of impact craters yield a wealth of information about Martian geology, providing clues to the relative age, local composition and erosional history of the surface. Martian craters are also of intrinsic geophysical interest, given that the processes by which they form are not entirely clear, especially cratering in ice-saturated regoliths (Plesko et al. 2004, AGU) which appear common on Mars (Squyres and Carr 1986). However, the deluge of data over the last decade has made comprehensive manual counts prohibitive, except in select regions. Given that most small craters on Mars may be secondaries from a few very recent impact events (McEwen et al. in press, Icarus 2004), using select regions for age dating introduces considerable potential for sampling error. Automation is thus an enabling planetary science technology. In contrast to machine counts, human counts are prone to human decision making, thus not intrinsically reproducible. One can address human "noise" by averaging over many human counts (Kanefsky et al. 2001), but this multiplies the already laborious effort required. In this study, we test automated crater counting algorithms developed with the Los Alamos National Laboratory genetic programming suite GENIE (Harvey et al., 2002) against established manual counts of craters in Elysium Planitia, using MOC and THEMIS data. We intend to establish the validity of our method against well-regarded hand counts (Hartmann et al. 2000), and then apply it generally to larger regions of Mars. Previous work on automated crater counting used customized algorithms (Bierhaus et al. 2003, Burl et al.. 2001). Algorithms generated by genetic programming have the advantage of requiring little time or user effort to generate, so it is relatively easy to generate a suite of algorithms for varied terrain types, or to compare results from multiple algorithms for improved accuracy (Plesko et al. 2003).

  1. Automated cell counts on CSF samples: A multicenter performance evaluation of the GloCyte system.

    PubMed

    Hod, E A; Brugnara, C; Pilichowska, M; Sandhaus, L M; Luu, H S; Forest, S K; Netterwald, J C; Reynafarje, G M; Kratz, A

    2017-09-07

    Automated cell counters have replaced manual enumeration of cells in blood and most body fluids. However, due to the unreliability of automated methods at very low cell counts, most laboratories continue to perform labor-intensive manual counts on many or all cerebrospinal fluid (CSF) samples. This multicenter clinical trial investigated if the GloCyte System (Advanced Instruments, Norwood, MA), a recently FDA-approved automated cell counter, which concentrates and enumerates red blood cells (RBCs) and total nucleated cells (TNCs), is sufficiently accurate and precise at very low cell counts to replace all manual CSF counts. The GloCyte System concentrates CSF and stains RBCs with fluorochrome-labeled antibodies and TNCs with nucleic acid dyes. RBCs and TNCs are then counted by digital image analysis. Residual adult and pediatric CSF samples obtained for clinical analysis at five different medical centers were used for the study. Cell counts were performed by the manual hemocytometer method and with the GloCyte System following the same protocol at all sites. The limits of the blank, detection, and quantitation, as well as precision and accuracy of the GloCyte, were determined. The GloCyte detected as few as 1 TNC/μL and 1 RBC/μL, and reliably counted as low as 3 TNCs/μL and 2 RBCs/μL. The total coefficient of variation was less than 20%. Comparison with cell counts obtained with a hemocytometer showed good correlation (>97%) between the GloCyte and the hemocytometer, including at very low cell counts. The GloCyte instrument is a precise, accurate, and stable system to obtain red cell and nucleated cell counts in CSF samples. It allows for the automated enumeration of even very low cell numbers, which is crucial for CSF analysis. These results suggest that GloCyte is an acceptable alternative to the manual method for all CSF samples, including those with normal cell counts. © 2017 John Wiley & Sons Ltd.

  2. Relationship between platelet count and 30-day clinical outcomes after percutaneous coronary interventions. Pooled analysis of four ISAR trials.

    PubMed

    Iijima, Raisuke; Ndrepepa, Gjin; Mehilli, Julinda; Bruskina, Olga; Schulz, Stefanie; Schömig, Albert; Kastrati, Adnan

    2007-10-01

    Platelets play an important role in the development of major adverse cardiac events (MACE) following percutaneous coronary intervention (PCI). The impact of platelet count on the outcome of patients undergoing PCI after pre-treatment with clopidogrel is unknown. The study included 5,256 patients enrolled in four randomized trials - ISAR-REACT, ISAR-SMART2, ISAR-SWEET, and ISAR-REACT2 - which assessed the value of abciximab in patients with coronary artery disease (CAD) undergoing PCI after pre-treatment with 600 mg of clopidogrel. Platelet count was measured at baseline before PCI. Primary endpoint was the 30-day incidence of MACE, secondary endpoint was mortality. The tertiles of platelet counts were: lower tertile (<198 x 10(9)/L; n = 1,726), middle tertile (198-244 x 10(9)/L; n = 1,750) and upper tertile (>244 x 10(9)/L; n = 1,780). The 30-day incidence of MACE was 6.7% (n = 116) among patients of the lower tertile, 6.3% (n = 111) among patients of the middle tertile, and 7.0% (n = 124) among patients of the upper tertile (P = 0.76). The 30-day mortality was 1.2% (n = 22) among patients of the upper tertile, 0.5% (n = 9) among patients of middle tertile and 0.6% (n = 11) among patients of the lower tertile (P = 0.04). Q-wave myocardial infarction occurred in 1.3% of patients (n = 23) in the upper tertile, 0.7% of patients (n = 13) in the middle tertile and 0.5% of patients (n = 8) in the lower tertile (P = 0.02). Platelet count was an independent correlate of 30-day mortality (hazard ratio 2.69, 95% confidence interval 1.08-6.67; P = 0.033 for the third vs. the first tertile). In conclusion, in patients with CAD undergoing PCI after pre-treatment with 600 mg clopidogrel, baseline platelet count predicts 30-day mortality.

  3. Elevated Platelet Count as Predictor of Recurrence in Rectal Cancer Patients Undergoing Preoperative Chemoradiotherapy Followed by Surgery

    PubMed Central

    Toiyama, Yuji; Inoue, Yasuhiro; Kawamura, Mikio; Kawamoto, Aya; Okugawa, Yoshinaga; Hiro, Jyunichiro; Saigusa, Susumu; Tanaka, Koji; Mohri, Yasuhiko; Kusunoki, Masato

    2015-01-01

    The impact of systemic inflammatory response (SIR) on prognostic and predictive outcome in rectal cancer after neoadjuvant chemoradiotherapy (CRT) has not been fully investigated. This retrospective study enrolled 89 patients with locally advanced rectal cancer who underwent neoadjuvant CRT and for whom platelet (PLT) counts and SIR status [neutrophil/lymphocyte ratio (NLR) and platelet/lymphocyte ratio (PLR)] were available. Both clinical values of PLT and SIR status in rectal cancer patients were investigated. Elevated PLT, NLR, PLR, and pathologic TNM stage III [ypN(+)] were associated with significantly poor overall survival (OS). Elevated PLT, NLR, and ypN(+) were shown to independently predict OS. Elevated PLT and ypN(+) significantly predicted poor disease-free survival (DFS). Elevated PLT was identified as the only independent predictor of DFS. PLT counts are a promising pre-CRT biomarker for predicting recurrence and poor prognosis in rectal cancer. PMID:25692418

  4. Development of a Novel Automated Hair Counting System for the Quantitative Evaluation of Laser Hair Removal.

    PubMed

    Lim, Hyoung-Woo; Cho, Minwoo; Lee, Dong-Hun; Koh, Wooseok; Kim, Youdan; Chung, Jin Ho; Kim, Sungwan

    2017-02-01

    We aimed to develop and validate a novel computer-assisted automated hair counting system for the quantitative evaluation of laser hair removal (LHR). We developed a computer-aided image processing system to count hairs on shaved skin and validated its performance through clinical trials. Five volunteers of Fitzpatrick skin type III-IV volunteered and were tested on both thighs. The system automatically detects hair and places a "+" sign on each hair site for every positive detection. This method allows clinicians to check whether a hair has been counted or not. We analyzed the difference in the hair counts between the proposed system (automatic) and those by human observers (manual). The hair counts from the proposed system and the manual counts were compared. The percentage error between automatic and manual counting was <5% in each subject. The data of the two groups were statistically verified with Student's independent t-test. The averages were statistically equivalent between the two groups. The proposed system showed significant time saving in terms of counting. A dependable, accurate, and fast method of counting hairs on shaved skin through a computer-aided image processing system was developed and validated. The "+" signs on the image to indicate detection allows clinicians to compare with the original image and detect any omission or redundancy. The proposed system is expected to be reliable in analyzing the results of multiple skin-related treatments, including LHR and hair transplantation. Further, it is expected to be widely applicable for use in the clinic.

  5. Improving reliability of live/dead cell counting through automated image mosaicing.

    PubMed

    Piccinini, Filippo; Tesei, Anna; Paganelli, Giulia; Zoli, Wainer; Bevilacqua, Alessandro

    2014-12-01

    Cell counting is one of the basic needs of most biological experiments. Numerous methods and systems have been studied to improve the reliability of counting. However, at present, manual cell counting performed with a hemocytometer still represents the gold standard, despite several problems limiting reproducibility and repeatability of the counts and, at the end, jeopardizing their reliability in general. We present our own approach based on image processing techniques to improve counting reliability. It works in two stages: first building a high-resolution image of the hemocytometer's grid, then counting the live and dead cells by tagging the image with flags of different colours. In particular, we introduce GridMos (http://sourceforge.net/p/gridmos), a fully-automated mosaicing method to obtain a mosaic representing the whole hemocytometer's grid. In addition to offering more significant statistics, the mosaic "freezes" the culture status, thus permitting analysis by more than one operator. Finally, the mosaic achieved can thus be tagged by using an image editor, thus markedly improving counting reliability. The experiments performed confirm the improvements brought about by the proposed counting approach in terms of both reproducibility and repeatability, also suggesting the use of a mosaic of an entire hemocytometer's grid, then labelled trough an image editor, as the best likely candidate for the new gold standard method in cell counting. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. High-resolution particle analysis--its application to platelet counting and suggestions for further application in blood cell analysis.

    PubMed

    Haynes, J L

    1980-01-01

    The characteristics of an instrument for high-resolution particle analysis in flow are discussed. It employs a combination of hydrodynamic focusing, fluid resistors, and electronic techniques to achieve precision and ease of use heretofore unobtainable in a moderate-cost clinical instrument. Its application to whole blood platelet counting is discussed, and suggestions are made for its possible application to a wide variety of blood cell measurements.

  7. Severe subcutaneous hematoma in a patient with psoriatic arthritis: Changes of platelet count in psoriatic patients with biologic agents.

    PubMed

    Maya, Yuka; Fujita, Yasuyuki; Nakayama, Chihiro; Kitamura, Shinya; Hata, Hiroo; Arita, Ken; Shimizu, Hiroshi

    2017-07-22

    The effectiveness of biologics has changed therapeutic strategies for psoriasis dramatically, but biologics are known to have various adverse effects. We report a 63-year-old woman with psoriatic arthritis who suddenly developed a subcutaneous hematoma after being successfully treated with adalimumab. As she had also suffered from alcoholic cirrhosis, we speculated that she had developed thrombocytopenia severe enough to cause a subcutaneous hematoma. Furthermore, we investigated the changes of platelet counts in 65 psoriatic patients treated with biologics at a single institute from 2010 to 2016. Platelet counts were found to have decreased by 17.4 ± 2.8% during adalimumab therapy (n = 16), 18.5 ± 3.8% during infliximab therapy (n = 17), 14.8 ± 2.1% during ustekinumab therapy (n = 20) and 18.5 ± 5.1% during secukinumab therapy (n = 12). Platelet counts decrease after the administration of biologics in accordance with disease activity, and there is the potential risk of subcutaneous hematoma and other adverse effects. When administrating biologics to psoriatic patients, especially to those with chronic liver disease, dermatologists should carefully monitor for thrombocytopenia. © 2017 Japanese Dermatological Association.

  8. Automated cell colony counting and analysis using the circular Hough image transform algorithm (CHiTA)

    NASA Astrophysics Data System (ADS)

    Bewes, J. M.; Suchowerska, N.; McKenzie, D. R.

    2008-11-01

    We present an automated cell colony counting method that is flexible, robust and capable of providing more in-depth clonogenic analysis than existing manual and automated approaches. The full form of the Hough transform without approximation has been implemented, for the first time. Improvements in computing speed have facilitated this approach. Colony identification was achieved by pre-processing the raw images of the colonies in situ in the flask, including images of the flask edges, by erosion, dilation and Gaussian smoothing processes. Colony edges were then identified by intensity gradient field discrimination. Our technique eliminates the need for specialized hardware for image capture and enables the use of a standard desktop scanner for distortion-free image acquisition. Additional parameters evaluated included regional colony counts, average colony area, nearest neighbour distances and radial distribution. This spatial and qualitative information extends the utility of the clonogenic assay, allowing analysis of spatially-variant cytotoxic effects. To test the automated system, two flask types and three cell lines with different morphology, cell size and plating density were examined. A novel Monte Carlo method of simulating cell colony images, as well as manual counting, were used to quantify algorithm accuracy. The method was able to identify colonies with unusual morphology, to successfully resolve merged colonies and to correctly count colonies adjacent to flask edges.

  9. Preoperative platelet count and postoperative blood loss in patients undergoing hip surgery: an inverse correlation.

    PubMed

    Monreal, M; Lafoz, E; Llamazares, J; Roncales, J; Roca, J; Granero, X

    1996-01-01

    In a previous study we tried to assess the clinical usefulness of platelet count (PlC) to confirm whether postoperative pulmonary embolism could be suspected early. Unexpectedly, the 19 patients who subsequently developed pulmonary embolism had significantly lower mean PlC levels even before surgery. In an attempt to discover whether the preoperative PlC levels were associated with a different incidence of postoperative blood loss, we decided to retrospectively study the relationship between preoperative PlC levels and the consequences of blood loss. There were 459 consecutive patients undergoing hip surgery. After excluding 5 patients who died during the first 3 postoperative days, and 16 patients who bled from a definitive anatomic site, there were 438 patients. Blood loss was considered to be excessive when two or more of the following conditions were present: (1) total transfusion requirements exceeding 1,000 ml whole blood or 2 units of packed red cells; (2) a drop in hemoglobin level of 5 g/dl or more, and (3) a hemoglobin level below 8 g/dl at any moment during the first 8 postoperative days. Blood loss was considered to be excessive in 91 patients. Preoperative PlC levels were significantly lower in these patients as compared to patients without the condition (204 +/- 52 vs. 236 +/- 79 x 10(9) liter-1; p = 0.0002). When patients were classified according to the quartiles of preoperative PlC, the odds ratio of developing excessive blood loss was 0.69 (95% CI: 0.38-1.26) in patients in the second quartile; 0.57 (95% CI: 0.30-1.06) in the third quartile, and 0.27 (95% CI: 0.13-0.57) in patients in the highest quartile. After adjusting for age, sex, type of surgery and type of prophylaxis, the preoperative PlC levels maintained a statistically significant inverse correlation with postoperative blood loss.

  10. Intravenous Iron Repletion Does Not Significantly Decrease Platelet Counts in CKD Patients with Iron Deficiency Anemia

    PubMed Central

    Dossabhoy, Neville R.; Gascoyne, Rebecca; Turley, Steven

    2013-01-01

    Purpose. We sought to investigate the effect of IV iron repletion on platelet (PLT) counts in CKD patients with iron deficiency anemia (IDA). Methods. We conducted a retrospective chart review, including all patients with CKD and IDA who were treated with iron dextran total dose infusion (TDI) between 2002 and 2007. Patient demographics were noted, and laboratory values for creatinine, hemoglobin (Hgb), iron stores and PLT were recorded pre- and post-dose. Results. 153 patients received a total of 251 doses of TDI (mean ± SD = 971 ± 175 mg); age 69 ± 12 years and Creatinine 3.3 ± 1.9 mg/dL. All CKD stages were represented (stage 4 commonest). Hgb and Fe stores improved post-TDI (P ≪ 0.001). There was a very mild decrease in PLT (pre-TDI 255 versus post-TDI 244, P = 0.30). The mild reduction in PLT after TDI remained non-significant (P > 0.05) when data was stratified by molecular weight (MW) of iron dextran used (low versus high), as well as by dose administered (<1000 versus ≥1000 mg). Linear regression analysis between pre-dose PLT and Tsat and Fe showed R2 of 0.01 and 0.04, respectively. Conclusion. Correction of iron deficiency did not significantly lower PLT in CKD patients, regardless of MW or dose used. Correlation of PLT to severity of iron deficiency was very weak. PMID:23476772

  11. Intravenous Iron Repletion Does Not Significantly Decrease Platelet Counts in CKD Patients with Iron Deficiency Anemia.

    PubMed

    Dossabhoy, Neville R; Gascoyne, Rebecca; Turley, Steven

    2013-01-01

    Purpose. We sought to investigate the effect of IV iron repletion on platelet (PLT) counts in CKD patients with iron deficiency anemia (IDA). Methods. We conducted a retrospective chart review, including all patients with CKD and IDA who were treated with iron dextran total dose infusion (TDI) between 2002 and 2007. Patient demographics were noted, and laboratory values for creatinine, hemoglobin (Hgb), iron stores and PLT were recorded pre- and post-dose. Results. 153 patients received a total of 251 doses of TDI (mean ± SD = 971 ± 175 mg); age 69 ± 12 years and Creatinine 3.3 ± 1.9 mg/dL. All CKD stages were represented (stage 4 commonest). Hgb and Fe stores improved post-TDI (P ≪ 0.001). There was a very mild decrease in PLT (pre-TDI 255 versus post-TDI 244, P = 0.30). The mild reduction in PLT after TDI remained non-significant (P > 0.05) when data was stratified by molecular weight (MW) of iron dextran used (low versus high), as well as by dose administered (<1000 versus ≥1000 mg). Linear regression analysis between pre-dose PLT and Tsat and Fe showed R2 of 0.01 and 0.04, respectively. Conclusion. Correction of iron deficiency did not significantly lower PLT in CKD patients, regardless of MW or dose used. Correlation of PLT to severity of iron deficiency was very weak.

  12. Pneumatic tube system transport does not alter platelet function in optical and whole blood aggregometry, prothrombin time, activated partial thromboplastin time, platelet count and fibrinogen in patients on anti-platelet drug therapy

    PubMed Central

    Enko, Dietmar; Mangge, Harald; Münch, Andreas; Niedrist, Tobias; Mahla, Elisabeth; Metzler, Helfried; Prüller, Florian

    2017-01-01

    Introduction The aim of this study was to assess pneumatic tube system (PTS) alteration on platelet function by the light transmission aggregometry (LTA) and whole blood aggregometry (WBA) method, and on the results of platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen. Materials and methods Venous blood was collected into six 4.5 mL VACUETTE® 9NC coagulation sodium citrate 3.8% tubes (Greiner Bio-One International GmbH, Kremsmünster, Austria) from 49 intensive care unit (ICU) patients on dual anti-platelet therapy and immediately hand carried to the central laboratory. Blood samples were divided into 2 Groups: Group 1 samples (N = 49) underwent PTS (4 m/s) transport from the central laboratory to the distant laboratory and back to the central laboratory, whereas Group 2 samples (N = 49) were excluded from PTS forces. In both groups, LTA and WBA stimulated with collagen, adenosine-5’-diphosphate (ADP), arachidonic acid (AA) and thrombin-receptor-activated-peptide 6 (TRAP-6) as well as platelet count, PT, APTT, and fibrinogen were performed. Results No statistically significant differences were observed between blood samples with (Group 1) and without (Group 2) PTS transport (P values from 0.064 – 0.968). The AA-induced LTA (bias: 68.57%) exceeded the bias acceptance limit of ≤ 25%. Conclusions Blood sample transportation with computer controlled PTS in our hospital had no statistically significant effects on platelet aggregation determined in patients with anti-platelet therapy. Although AA induced LTA showed a significant bias, the diagnostic accuracy was not influenced. PMID:28392742

  13. [Maternal and perinatal surgical complications in low platelet count for HELLP syndrome in severe preeclampsia-eclampsia in intensive care].

    PubMed

    Basavilvazo Rodríguez, Antonia; Pacheco Pérez, Claudia; Lemus Rocha, Roberto; Martínez Pérez, José Ma; Martínez Martínez, Armando; Hernández-Valencia, Marcelino

    2003-08-01

    The preeclampsia is the first cause of maternal morbility, with increase in the obstetric complications when it is associated to HELLP syndrome, for the low platelets that even involves to the neonate. This study was carried out in the patients accepted in the intensive Adults Cares Unit in the period of one year, surgical complications and the perinatal results were determined in women with low platelet count for HELLP syndrome in preeclampsia-eclampsia. Three groups were formed according to the platelets account and then were analyzed using chi square to determine association among these groups of patients, as well as mean and standard deviation (M +/- DE) to describe results. Forty patients were studied with low platelets by HELLP syndrome in preeclampsia-eclampsia, where the distribution for the group with platelets < 50,000 were 12 patients (30%), in the group among 51,000-100,000 of 18 cases (45%), and of 101,000-150,000 were of 10 cases (25%). The mean of gestas was of 2.3 +/- 1.2, more frequent delivery was for cesarean section in 39 cases (97.5%) and a single case for vaginal via (2.5%), a maternal death was presented (8.3%). The surgical reintervention was observed with more frequency in the group of < 50,000 platelets, the most frequent cause in these reinterventions was the hipovolemic shock. Also in this group the perinatal mortality was presented in 3 cases (25%) and the asphyxia at the birth with Apgar < 6 was presented in 5 cases (41.7%). A bigger morbility was observed inversely proportional to the account platelets, being the renal failure the cause most frequent of this morbility in the three groups. The low platelets account contribute in a direct way in the obstetric complications, since there are more surgical reinterventions, with bled in the transsurgical and increase in the days of intrahospitalary stay. Also with smaller account platelet, there are bigger prematural index, asphyxia and perinatal mortality in the newborn of mothers with

  14. Carica papaya Leaves Juice Significantly Accelerates the Rate of Increase in Platelet Count among Patients with Dengue Fever and Dengue Haemorrhagic Fever.

    PubMed

    Subenthiran, Soobitha; Choon, Tan Chwee; Cheong, Kee Chee; Thayan, Ravindran; Teck, Mok Boon; Muniandy, Prem Kumar; Afzan, Adlin; Abdullah, Noor Rain; Ismail, Zakiah

    2013-01-01

    The study was conducted to investigate the platelet increasing property of Carica papaya leaves juice (CPLJ) in patients with dengue fever (DF). An open labeled randomized controlled trial was carried out on 228 patients with DF and dengue haemorrhagic fever (DHF). Approximately half the patients received the juice, for 3 consecutive days while the others remained as controls and received the standard management. Their full blood count was monitored 8 hours for 48 hours. Gene expression studies were conducted on the ALOX 12 and PTAFR genes. The mean increase in platelet counts were compared in both groups using repeated measure ANCOVA. There was a significant increase in mean platelet count observed in the intervention group (P < 0.001) but not in the control group 40 hours since the first dose of CPLJ. Comparison of mean platelet count between intervention and control group showed that mean platelet count in intervention group was significantly higher than control group after 40 and 48 hours of admission (P < 0.01). The ALOX 12 (FC  =  15.00) and PTAFR (FC  =  13.42) genes were highly expressed among those on the juice. It was concluded that CPLJ does significantly increase the platelet count in patients with DF and DHF.

  15. Does Carica papaya leaf-extract increase the platelet count? An experimental study in a murine model.

    PubMed

    Dharmarathna, Sinhalagoda Lekamlage Chandi Asoka; Wickramasinghe, Susiji; Waduge, Roshitha Nilmini; Rajapakse, Rajapakse Peramune Veddikkarage Jayanthe; Kularatne, Senanayake Abeysinghe Mudiyanselage

    2013-09-01

    To investigate the potential role of fresh Carica papaya (C. papaya) leaf extract on haematological and biochemical parameters and toxicological changes in a murine model. In total 36 mice were used for the trial. Fresh C. papaya leaf extract [0.2 mL (2 g)/mouse] was given only to the test group (18 mice). General behavior, clinical signs and feeding patterns were recorded. Blood and tissue samples were collected at intervals. Haematological parameters including platelet, red blood cell (RBC), white blood cell (WBC), packed cell volume (PCV), serum biochemistry including serum creatinine, serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) were determined. Organs for possible histopathological changes were examined. Neither group exhibited alteration of behavior or reduction in food and water intake. Similarly, no significant changes in SGOT, SGPT and serum creatinine levels were detected in the test group. Histopathological organ changes were not observed in either group of mice except in three liver samples of the test group which had a mild focal necrosis. The platelet count (11.33±0.35)×10⁵/µL (P=0.00004) and the RBC count (7.97±0.61)×10⁶/µL (P=0.00003) were significantly increased in the test group compared to that of the controls. However, WBC count and PCV (%) values were not changed significantly in the test group. The platelet count in the test group started to increase significantly from Day 3 (3.4±0.18×10⁵/µL), reaching almost a fourfold higher at Day 21 (11.3×10⁵/µL), while it was 3.8×10⁵/µL and 5.5×10⁵/µL at Day 3 and Day 21 respectively in the control. Likewise, the RBC count in the test group increased from 6×10⁶/µL to 9×10⁶/ µL at Day 21 while it remained near constant in the control group (6×10⁶/µL). Fresh C. papaya leaf extract significantly increased the platelet and RBC counts in the test group as compared to controls. Therefore, it is very important to identify

  16. Does Carica papaya leaf-extract increase the platelet count? An experimental study in a murine model

    PubMed Central

    Dharmarathna, Sinhalagoda Lekamlage Chandi Asoka; Wickramasinghe, Susiji; Waduge, Roshitha Nilmini; Rajapakse, Rajapakse Peramune Veddikkarage Jayanthe; Kularatne, Senanayake Abeysinghe Mudiyanselage

    2013-01-01

    Objective To investigate the potential role of fresh Carica papaya (C. papaya) leaf extract on haematological and biochemical parameters and toxicological changes in a murine model. Methods In total 36 mice were used for the trial. Fresh C. papaya leaf extract [0.2 mL (2 g)/mouse] was given only to the test group (18 mice). General behavior, clinical signs and feeding patterns were recorded. Blood and tissue samples were collected at intervals. Haematological parameters including platelet, red blood cell (RBC), white blood cell (WBC), packed cell volume (PCV), serum biochemistry including serum creatinine, serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) were determined. Organs for possible histopathological changes were examined. Results Neither group exhibited alteration of behavior or reduction in food and water intake. Similarly, no significant changes in SGOT, SGPT and serum creatinine levels were detected in the test group. Histopathological organ changes were not observed in either group of mice except in three liver samples of the test group which had a mild focal necrosis. The platelet count (11.33±0.35)×105/µL (P=0.000 04) and the RBC count (7.97±0.61)×106/µL (P=0.000 03) were significantly increased in the test group compared to that of the controls. However, WBC count and PCV (%) values were not changed significantly in the test group. The platelet count in the test group started to increase significantly from Day 3 (3.4±0.18×105/µL), reaching almost a fourfold higher at Day 21 (11.3×105/µL), while it was 3.8×105/µL and 5.5×105/µL at Day 3 and Day 21 respectively in the control. Likewise, the RBC count in the test group increased from 6×106/µL to 9×106/ µL at Day 21 while it remained near constant in the control group (6×106/µL). Conclusions Fresh C. papaya leaf extract significantly increased the platelet and RBC counts in the test group as compared to controls. Therefore, it is very

  17. Pseudothrombocytopenia or platelet clumping as a possible cause of low platelet count in patients with viral infection: a case series from single institution focusing on hepatitis A virus infection.

    PubMed

    Choe, W-H; Cho, Y-U; Chae, J-D; Kim, S-H

    2013-02-01

    Pseudothrombocytopenia (PTCP) is the phenomenon of ethylenediaminetetraacetic acid anticoagulant-activated platelet clumping, which results in artificially low platelet counts. Other investigators have reported a few cases of PTCP associated with viral infections. The objective of this study was to demonstrate the association of viral infection with PTCP. Medical records of patients with thrombocytopenia who were tested for peripheral blood smear examination between March 2009 and February 2011 were reviewed for platelet clumping and viral infection. Thrombocytopenic patients with viral infection had a higher frequency of platelet clumping than those with other diseases, which was statistically significant (13.8% vs. 6.5%, respectively: P = 0.003). Among the 18 cases where PTCP or platelet clumping was related to viral infection, hepatitis A virus infection (72.2%) was most common, followed by cytomegalovirus (11.1%) and influenza A H1N1 infections (5.6%). A third (33.3%) of the patients had platelet counts <100 × 10⁹/L. Pseudothrombocytopenia or platelet clumping should be considered in patients with acute viral infection, particularly if the platelet count is unexpectedly low, because failure to recognize PTCP may lead to unnecessary diagnostic tests and patient mismanagement. © 2012 Blackwell Publishing Ltd.

  18. Automated preparation of whole blood-derived platelets suspended in two different platelet additive solutions and stored for 7 days.

    PubMed

    Cid, Joan; Magnano, Laura; Molina, Patricia; Diaz-Ricart, Maribel; Martínez, Nuria; Maymó, Rosa M; Puig, Lluís; Lozano, Miguel; Escolar, Ginés; Galán, Ana M

    2014-02-01

    The Atreus system (Terumo BCT) automates the preparation of blood components from whole blood donations. Intermediate platelet (PLT) products can be pooled manually or with the OrbiSac (Terumo BCT) and suspended in different PLT additive solutions (PASs) to obtain PLT concentrates (PCs). The aim of our study was to compare the in vitro PLT quality of PCs obtained with either the Atreus 2C+ and the OrbiSac or the Atreus 3C and suspended in PAS-II or PAS-IIIM during storage for up to 7 days. We prepared eight PCs from buffy coats obtained with Atreus 2C+, pooled with the OrbiSac, and suspended in PAS-II and eight PCs from interim PLT units obtained with the Atreus 3C and suspended either in PAS-II or in PAS-IIIM. We measured volume, PLT content, and mean PLT component and performed metabolic assays (pH, glucose, lactate, pO₂, and pCO₂) and flow cytometry analyses (GPIb, GPIIbIIIa, GPIV, CD62P, CD63, von Willebrand factor [vWF], fibrinogen, Factor V, and annexin V). PCs prepared with the Atreus 3C showed lower volume and higher PLT concentration when compared with PCs prepared with the Atreus 2C+ and the OrbiSac (p < 0.05). Glucose consumption rate and the expression of CD62P, CD63, and vWF were lower in PCs suspended in PAS-IIIM when compared with PCs suspended in PAS-II (p < 0.05). PCs prepared with the Atreus 3C and suspended in PAS-IIIM preserve satisfactorily the in vitro PLT quality during 7-day storage. PLT activation during a 7-day storage period was lower when the storage solution was PAS-IIIM in comparison with PAS-II. © 2013 American Association of Blood Banks.

  19. Genome-wide Association Study of Platelet Count Identifies Ancestry-Specific Loci in Hispanic/Latino Americans

    PubMed Central

    Schick, Ursula M.; Jain, Deepti; Hodonsky, Chani J.; Morrison, Jean V.; Davis, James P.; Brown, Lisa; Sofer, Tamar; Conomos, Matthew P.; Schurmann, Claudia; McHugh, Caitlin P.; Nelson, Sarah C.; Vadlamudi, Swarooparani; Stilp, Adrienne; Plantinga, Anna; Baier, Leslie; Bien, Stephanie A.; Gogarten, Stephanie M.; Laurie, Cecelia A.; Taylor, Kent D.; Liu, Yongmei; Auer, Paul L.; Franceschini, Nora; Szpiro, Adam; Rice, Ken; Kerr, Kathleen F.; Rotter, Jerome I.; Hanson, Robert L.; Papanicolaou, George; Rich, Stephen S.; Loos, Ruth J.F.; Browning, Brian L.; Browning, Sharon R.; Weir, Bruce S.; Laurie, Cathy C.; Mohlke, Karen L.; North, Kari E.; Thornton, Timothy A.; Reiner, Alex P.

    2016-01-01

    Platelets play an essential role in hemostasis and thrombosis. We performed a genome-wide association study of platelet count in 12,491 participants of the Hispanic Community Health Study/Study of Latinos by using a mixed-model method that accounts for admixture and family relationships. We discovered and replicated associations with five genes (ACTN1, ETV7, GABBR1-MOG, MEF2C, and ZBTB9-BAK1). Our strongest association was with Amerindian-specific variant rs117672662 (p value = 1.16 × 10−28) in ACTN1, a gene implicated in congenital macrothrombocytopenia. rs117672662 exhibited allelic differences in transcriptional activity and protein binding in hematopoietic cells. Our results underscore the value of diverse populations to extend insights into the allelic architecture of complex traits. PMID:26805783

  20. Genome-wide Association Study of Platelet Count Identifies Ancestry-Specific Loci in Hispanic/Latino Americans.

    PubMed

    Schick, Ursula M; Jain, Deepti; Hodonsky, Chani J; Morrison, Jean V; Davis, James P; Brown, Lisa; Sofer, Tamar; Conomos, Matthew P; Schurmann, Claudia; McHugh, Caitlin P; Nelson, Sarah C; Vadlamudi, Swarooparani; Stilp, Adrienne; Plantinga, Anna; Baier, Leslie; Bien, Stephanie A; Gogarten, Stephanie M; Laurie, Cecelia A; Taylor, Kent D; Liu, Yongmei; Auer, Paul L; Franceschini, Nora; Szpiro, Adam; Rice, Ken; Kerr, Kathleen F; Rotter, Jerome I; Hanson, Robert L; Papanicolaou, George; Rich, Stephen S; Loos, Ruth J F; Browning, Brian L; Browning, Sharon R; Weir, Bruce S; Laurie, Cathy C; Mohlke, Karen L; North, Kari E; Thornton, Timothy A; Reiner, Alex P

    2016-02-04

    Platelets play an essential role in hemostasis and thrombosis. We performed a genome-wide association study of platelet count in 12,491 participants of the Hispanic Community Health Study/Study of Latinos by using a mixed-model method that accounts for admixture and family relationships. We discovered and replicated associations with five genes (ACTN1, ETV7, GABBR1-MOG, MEF2C, and ZBTB9-BAK1). Our strongest association was with Amerindian-specific variant rs117672662 (p value = 1.16 × 10(-28)) in ACTN1, a gene implicated in congenital macrothrombocytopenia. rs117672662 exhibited allelic differences in transcriptional activity and protein binding in hematopoietic cells. Our results underscore the value of diverse populations to extend insights into the allelic architecture of complex traits.

  1. The Prognostic Value of Platelet Count in Patients With Hepatocellular Carcinoma

    PubMed Central

    Pang, Qing; Qu, Kai; Zhang, Jing-Yao; Song, Si-Dong; Liu, Su-Shun; Tai, Ming-Hui; Liu, Hao-Chen; Liu, Chang

    2015-01-01

    Abstract Thrombocytopenia has been acknowledged to be a crucial risk factor for cirrhosis formation and hepatocarcinogenesis in chronic liver diseases. However, to date, the association between platelet count (PLT) and the prognosis of hepatocellular carcinoma (HCC) remains inconsistent and controversial. The aim of the present study was to determine whether PLT could be used as a useful predictor of survival in patients with HCC. We performed systematic review in online databases, including PubMed, EmBase, and Web of Science, from inception until 2014. Studies were included if a statistical relationship was investigated between PLT and survival for HCC, and hazard ratio (HR) and 95% confidence intervals (CIs) for overall survival (OS) or recurrence-free survival (RFS) were provided. The quality of each included study was assessed by Newcastle–Ottawa scale score. To synthesize these studies, a random-effects model or a fixed-effects model was applied as appropriate. Then, we calculated heterogeneity, performed sensitivity analysis, tested publication bias, and did subgrouped and meta-regression analysis. Finally, we identified 33 eligible articles (published from 1998 to 2014) involved 5545 patients by retrieval. A low level of preoperative PLT was found to be significantly associated with a poor survival of HCC. Irrespective of the therapy used, the pooled HRs for OS and RFS were 1.41 (95% CI, 1.14–1.75) and 1.44 (95% CI, 1.13–1.83), respectively. Specifically, in patients who underwent liver resection, the pooled HRs for OS and RFS were 1.67 (95% CI, 1.22–2.27) and 1.44 (95% CI, 1.04–1.99), respectively. Furthermore, patients with preoperative thrombocytopenia (PLT < 100 × 109/L) had a worse OS (HR: 1.73, 95% CI, 1.29–2.32) and RFS (HR: 1.57, 95% CI, 1.31–1.87) in comparison with patients without thrombocytopenia. All our findings showed no significant changes due to the removal of any study or the use of an opposite-effects model, and

  2. Identification and red blood cell automated counting from blood smear images using computer-aided system.

    PubMed

    Acharya, Vasundhara; Kumar, Preetham

    2017-08-17

    Red blood cell count plays a vital role in identifying the overall health of the patient. Hospitals use the hemocytometer to count the blood cells. Conventional method of placing the smear under microscope and counting the cells manually lead to erroneous results, and medical laboratory technicians are put under stress. A computer-aided system will help to attain precise results in less amount of time. This research work proposes an image-processing technique for counting the number of red blood cells. It aims to examine and process the blood smear image, in order to support the counting of red blood cells and identify the number of normal and abnormal cells in the image automatically. K-medoids algorithm which is robust to external noise is used to extract the WBCs from the image. Granulometric analysis is used to separate the red blood cells from the white blood cells. The red blood cells obtained are counted using the labeling algorithm and circular Hough transform. The radius range for the circle-drawing algorithm is estimated by computing the distance of the pixels from the boundary which automates the entire algorithm. A comparison is done between the counts obtained using the labeling algorithm and circular Hough transform. Results of the work showed that circular Hough transform was more accurate in counting the red blood cells than the labeling algorithm as it was successful in identifying even the overlapping cells. The work also intends to compare the results of cell count done using the proposed methodology and manual approach. The work is designed to address all the drawbacks of the previous research work. The research work can be extended to extract various texture and shape features of abnormal cells identified so that diseases like anemia of inflammation and chronic disease can be detected at the earliest.

  3. Serratia marcescens strains implicated in adverse transfusion reactions form biofilms in platelet concentrates and demonstrate reduced detection by automated culture.

    PubMed

    Greco-Stewart, V S; Brown, E E; Parr, C; Kalab, M; Jacobs, M R; Yomtovian, R A; Ramírez-Arcos, S M

    2012-04-01

    Serratia marcescens is a gram-negative bacterium that has been implicated in adverse transfusion reactions associated with contaminated platelet concentrates. The aim of this study was to investigate whether the ability of S. marcescens to form surface-attached aggregates (biofilms) could account for contaminated platelet units being missed during screening by the BacT/ALERT automated culture system. Seven S. marcescens strains, including biofilm-positive and biofilm-negative control strains and five isolates recovered from contaminated platelet concentrates, were grown in enriched Luria-Bertani medium and in platelets. Biofilm formation was examined by staining assay, dislodging experiments and scanning electron microscopy. Clinical strains were also analysed for their ability to evade detection by the BacT/ALERT system. All strains exhibited similar growth in medium and platelets. While only the biofilm-positive control strain formed biofilms in medium, this strain and three clinical isolates associated with transfusion reactions formed biofilms in platelet concentrates. The other two clinical strains, which had been captured during platelet screening by BacT/ALERT, failed to form biofilms in platelets. Biofilm-forming clinical isolates were approximately three times (P<0·05) more likely to be missed by BacT/ALERT screening than biofilm-negative strains. S. marcescens strains associated with transfusion reactions form biofilms under platelet storage conditions, and initial biofilm formation correlates with missed detection of contaminated platelet concentrates by the BacT/ALERT system. © 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.

  4. Field performance of a low-cost and fully-automated blood counting system operated by trained and untrained users (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Xie, Dengling; Xie, Yanjun; Liu, Peng; Tong, Lieshu; Chu, Kaiqin; Smith, Zachary J.

    2017-02-01

    Current flow-based blood counting devices require expensive and centralized medical infrastructure and are not appropriate for field use. In this paper we report a method to count red blood cells, white blood cells as well as platelets through a low-cost and fully-automated blood counting system. The approach consists of using a compact, custom-built microscope with large field-of-view to record bright-field and fluorescence images of samples that are diluted with a single, stable reagent mixture and counted using automatic algorithms. Sample collection is performed manually using a spring loaded lancet, and volume-metering capillary tubes. The capillaries are then dropped into a tube of pre-measured reagents and gently shaken for 10-30 seconds. The sample is loaded into a measurement chamber and placed on a custom 3D printed platform. Sample translation and focusing is fully automated, and a user has only to press a button for the measurement and analysis to commence. Cost of the system is minimized through the use of custom-designed motorized components. We performed a series of comparative experiments by trained and untrained users on blood from adults and children. We compare the performance of our system, as operated by trained and untrained users, to the clinical gold standard using a Bland-Altman analysis, demonstrating good agreement of our system to the clinical standard. The system's low cost, complete automation, and good field performance indicate that it can be successfully translated for use in low-resource settings where central hematology laboratories are not accessible.

  5. Importance of Low Preoperative Platelet Count in Selecting Patients for Resection of Hepatocellular Carcinoma: A Multi-Institutional Analysis

    PubMed Central

    Maithel, Shishir K; Kneuertz, Peter J; Kooby, David A; Scoggins, Charles R; Weber, Sharon M; Martin, Robert CG; McMasters, Kelly M; Cho, Clifford S; Winslow, Emily R; Wood, William C; Staley, Charles A

    2012-01-01

    BACKGROUND Low platelet count is a marker of portal hypertension but is not routinely included in the standard preoperative evaluation of patients with hepatocellular carcinoma (HCC) because it pertains to liver function (Child/model for end-stage liver disease [MELD] score) and tumor burden (Milan criteria). We hypothesized that low platelet count would be independently associated with increased perioperative morbidity and mortality after resection. STUDY DESIGN Patients treated with liver resection for HCC between January 2000 and January 2010 at 3 institutions were eligible. Preoperative platelet count, Child/MELD score, and tumor extent were recorded. Low preoperative platelet count (LPPC) was defined as <150 × 103/μL. Postoperative liver insufficiency (PLI) was defined as peak bilirubin >7 mg/dL or development of ascites. Univariate and multivariate regression was performed for predictors of major complications, PLI, and 60-day mortality. RESULTS A total of 231 patients underwent resection, of whom 196 (85%) were classified as Child A and 35 (15%) as Child B; median MELD score was 8. Overall, 168 (71%) had tumors that exceeded Milan criteria and 134 (58%) had major hepatectomy (≥3 Couinaud segments). Overall and major complication rates were 55% and 17%, respectively. PLI occurred in 25 patients (11%), and 21 (9%) died within 60 days of surgery. Patients with LPPC (n = 50) had a significantly increased number of major complications (28% versus 14%, p = 0.031), PLI (30% versus 6%, p = 0.001), and 60-day mortality (22% versus 6%, p = 0.001). When adjusted for Child/MELD score and tumor burden, LPPC remained independently associated with increased number of major complications (odds ratio [OR] 2.8, 95% confidence intervals [CI] 1.1 to 6.8, p = 0.026), PLI (OR 4.0, 95% CI 1.4 to 11.1, p = 0.008), and 60-day mortality (OR 4.6, 95% CI 1.5 to 14.6, p = 0.009). CONCLUSIONS LPPC is independently associated with increased major complications, PLI, and mortality

  6. Thrombocytopenia-associated multiple organ failure or severe haemolysis, elevated liver enzymes, low platelet count in a postpartum case.

    PubMed

    Jagia, Manish; Taqi, Salah; Hanafi, Mahmoud; Aisha, Fakeir

    2013-01-01

    Thrombocytopenia-associated multiple organ failure (TAMOF) is a thrombotic microangiopathic syndrome that includes thrombotic thrombocytopenic purpura, secondary thrombotic microangiopathy, and disseminated intravascular coagulation. We report a case of postpartum female who presented with TAMOF or severe Haemolysis, elevated liver enzymes, low platelet count (HELLP) which was managed with plasma exchange. This case report is to make clinicians aware that TAMOF, severe HELLP, and other differential diagnosis in a postpartum case have a thin differentiating line and plasma exchange can be considered as one of the management options.

  7. White blood cell and platelet count as adjuncts to standard clinical evaluation for risk assessment in patients at low probability of acute aortic syndrome.

    PubMed

    Morello, Fulvio; Cavalot, Giulia; Giachino, Francesca; Tizzani, Maria; Nazerian, Peiman; Carbone, Federica; Pivetta, Emanuele; Mengozzi, Giulio; Moiraghi, Corrado; Lupia, Enrico

    2017-08-01

    Pre-test probability assessment is key in the approach to suspected acute aortic syndromes (AASs). However, most patients with AAS-compatible symptoms are classified at low probability, warranting further evaluation for decision on aortic imaging. White blood cell count, platelet count and fibrinogen explore pathophysiological pathways mobilized in AASs and are routinely assayed in the workup of AASs. However, the diagnostic performance of these variables for AASs, alone and as a bundle, is unknown. We tested the hypothesis that white blood cell count, platelet count and/or fibrinogen at presentation may be applied as additional tools to standard clinical evaluation for pre-test risk assessment in patients at low probability of AAS. This was a retrospective observational study conducted on consecutive patients managed in our Emergency Department from 2009 to 2014 for suspected AAS. White blood cell count, platelet count and fibrinogen were assayed during evaluation in the Emergency Department. The final diagnosis was obtained by computed tomography angiography. The pre-test probability of AAS was defined according to guidelines. Of 1210 patients with suspected AAS, 1006 (83.1%) were classified at low probability, and 271 (22.4%) were diagnosed with AAS. Within patients at low probability, presence of at least one alteration among white blood cell count >9*10(3)/µl, platelet count <200*10(3)/µl and fibrinogen <350 mg/dl was associated with a sensitivity of 95.5% (89.7-98.5%) and a specificity of 18.3% (15.6-21.2%). In patients at low probability, white blood cell count >9*10(3)/µl and platelet count <200*10(3)/µl were found as independent predictors of AAS beyond established clinical risk markers. Within patients at low probability, the estimated risk of AAS based on the number of alterations amongst white blood cell count >9*10(3)/µl and platelet count <200*10(3)/µl was 2.7% (1.2-5.7%) with zero alterations, 11.3% (8.8-14.3%) with one alteration and 31.9% (24

  8. Curasan PRP kit vs. PCCS PRP system. Collection efficiency and platelet counts of two different methods for the preparation of platelet-rich plasma.

    PubMed

    Weibrich, Gernot; Kleis, Wilfried K G

    2002-08-01

    An important reason to improve methods of isolating platelet-rich plasma (PRP) is the potential use of autologous thrombocyte growth factors. In addition to discontinuous cell separation, two methods for extracting PRP that can be performed directly by the surgeon are now available. This study compared the suitability of these two methods for the preparation of PRP. Whole blood was drawn from 47 healthy donors (18 men, 29 women) aged 20-59 years (mean 29.9, SD 7.7). For each donor, PRP was separated by the PCCS method (PCCS Kit, 3i Implant Innovations, Palm Beach Gardens, FL, USA) and by the Curasan method (analogous to the PRP kit, Curasan, Kleinostheim, Germany). Thrombocyte counts differed significantly (sign test P = 0.001) between the donor blood (mean 290,000/ micro l, SD 86,000/ microl), the PCCS PRP preparation (mean 2,209,000/ microl, SD 901,000/ microl), and the Curasan PRP (mean 1,075,000/ micro l, SD 636,000/ microl). The correlation between the thrombocyte count in the PRP and the thrombocyte count in the donor whole blood was greater for the PCCS PRP (Spearman's correlation coefficient rS = 0.60) than for the Curasan PRP (r(S) = 0.34). A slight, clinically irrelevant, influence of gender on thrombocyte concentration in whole blood was found, but no influence of age was detected.

  9. An automated image analysis system to measure and count organisms in laboratory microcosms.

    PubMed

    Mallard, François; Le Bourlot, Vincent; Tully, Thomas

    2013-01-01

    1. Because of recent technological improvements in the way computer and digital camera perform, the potential use of imaging for contributing to the study of communities, populations or individuals in laboratory microcosms has risen enormously. However its limited use is due to difficulties in the automation of image analysis. 2. We present an accurate and flexible method of image analysis for detecting, counting and measuring moving particles on a fixed but heterogeneous substrate. This method has been specifically designed to follow individuals, or entire populations, in experimental laboratory microcosms. It can be used in other applications. 3. The method consists in comparing multiple pictures of the same experimental microcosm in order to generate an image of the fixed background. This background is then used to extract, measure and count the moving organisms, leaving out the fixed background and the motionless or dead individuals. 4. We provide different examples (springtails, ants, nematodes, daphnia) to show that this non intrusive method is efficient at detecting organisms under a wide variety of conditions even on faintly contrasted and heterogeneous substrates. 5. The repeatability and reliability of this method has been assessed using experimental populations of the Collembola Folsomia candida. 6. We present an ImageJ plugin to automate the analysis of digital pictures of laboratory microcosms. The plugin automates the successive steps of the analysis and recursively analyses multiple sets of images, rapidly producing measurements from a large number of replicated microcosms.

  10. Can mean platelet volume and mean platelet volume/platelet count ratio be used as a diagnostic marker for sepsis and systemic inflammatory response syndrome?

    PubMed Central

    Ates, Selma; Oksuz, Hafıze; Dogu, Bırsen; Bozkus, Fulsen; Ucmak, Hasan; Yanıt, Fadime

    2015-01-01

    Objectives: To determine whether the mean platelet volume (MPV) and MPV/platelet (PLT) values can be used in the study of sepsis and systemic inflammatory response syndrome (SIRS). Methods: In this retrospective case-controlled study, 69 sepsis, 69 SIRS patients, and 72 control group who were treated in the years 2012-2013 were reviewed, and both the MPV and MPV/PLT rates were evaluated in all groups at Kahramanmaras Sutcu Imam University Intensive Care Unit, Kahramanmaras, Turkey. Results: Statistically significant difference was found between sepsis, SIRS, and control groups when comparing the MPV and MPV/PLT ratio (p<0.05), and no significant difference was found between sepsis and SIRS groups in terms of MPV and MPV/PLT ratio (p>0.05). Mean platelet volume values for sepsis and control groups was 10.07/8.731 femtoliter (fL) (p=0.000), and 9.45/8.731 fL (p=0.000) for SIRS and control groups. In the group of sepsis patients, the MPV was found to be at cut-off 8.915, sensitivity 71%, and specificity 63.9%. In the group of patients with SIRS, MPV was found to be at cut-off 8.85, sensitivity 69.6%, and specificity 62.5%. For the MPV/PLT values, the specificity and sensitivity were found to be insignificant. Conclusion: This study shows that although there was no significant reduction in the PLT values between the sepsis and SIRS patients, the MPV and MPV/PLT ratio values were found to have significant differences. However, the specificity and sensitivity of the values were not reliable standard to be used as a test. PMID:26446329

  11. Can mean platelet volume and mean platelet volume/platelet count ratio be used as a diagnostic marker for sepsis and systemic inflammatory response syndrome?

    PubMed

    Ates, Selma; Oksuz, Hafıze; Dogu, Bırsen; Bozkus, Fulsen; Ucmak, Hasan; Yanıt, Fadıme

    2015-10-01

    To determine whether the mean platelet volume (MPV) and MPV/platelet (PLT) values can be used in the study of sepsis and systemic inflammatory response syndrome (SIRS). In this retrospective case-controlled study, 69 sepsis, 69 SIRS patients, and 72 control group who were treated in the years 2012-2013 were reviewed, and both the MPV and MPV/PLT rates were evaluated in all groups. Statistically significant difference was found between sepsis, SIRS, and control groups when comparing the MPV and MPV/PLT ratio (p less than 0.05), and no significant difference was found between sepsis and SIRS groups in terms of MPV and MPV/PLT ratio (p more than 0.05). Mean platelet volume values for sepsis and control groups was 10.07/8.731 femtoliter (fL) (p=0.000), and 9.45/8.731 fL (p=0.000) for SIRS and control groups. In the group of sepsis patients, the MPV was found to be at cut-off 8.915, sensitivity 71%, and specificity 63.9%. In the group of patients with SIRS, MPV was found to be at cut-off 8.85, sensitivity 69.6%, and specificity 62.5%. For the MPV/PLT values, the specificity and sensitivity were found to be insignificant. This study shows that although there was no significant reduction in the PLT values between the sepsis and SIRS patients, the MPV and MPV/PLT ratio values were found to have significant differences. However, the specificity and sensitivity of the values were not reliable standard to be used as a test.

  12. How many fish in a tank? Constructing an automated fish counting system by using PTV analysis

    NASA Astrophysics Data System (ADS)

    Abe, S.; Takagi, T.; Takehara, K.; Kimura, N.; Hiraishi, T.; Komeyama, K.; Torisawa, S.; Asaumi, S.

    2017-02-01

    Because escape from a net cage and mortality are constant problems in fish farming, health control and management of facilities are important in aquaculture. In particular, the development of an accurate fish counting system has been strongly desired for the Pacific Bluefin tuna farming industry owing to the high market value of these fish. The current fish counting method, which involves human counting, results in poor accuracy; moreover, the method is cumbersome because the aquaculture net cage is so large that fish can only be counted when they move to another net cage. Therefore, we have developed an automated fish counting system by applying particle tracking velocimetry (PTV) analysis to a shoal of swimming fish inside a net cage. In essence, we treated the swimming fish as tracer particles and estimated the number of fish by analyzing the corresponding motion vectors. The proposed fish counting system comprises two main components: image processing and motion analysis, where the image-processing component abstracts the foreground and the motion analysis component traces the individual's motion. In this study, we developed a Region Extraction and Centroid Computation (RECC) method and a Kalman filter and Chi-square (KC) test for the two main components. To evaluate the efficiency of our method, we constructed a closed system, placed an underwater video camera with a spherical curved lens at the bottom of the tank, and recorded a 360° view of a swimming school of Japanese rice fish (Oryzias latipes). Our study showed that almost all fish could be abstracted by the RECC method and the motion vectors could be calculated by the KC test. The recognition rate was approximately 90% when more than 180 individuals were observed within the frame of the video camera. These results suggest that the presented method has potential application as a fish counting system for industrial aquaculture.

  13. Comparing Manual Counting to Automated Image Analysis for the Assessment of Fungiform Papillae Density on Human Tongue.

    PubMed

    Piochi, Maria; Monteleone, Erminio; Torri, Luisa; Masi, Camilla; Almli, Valérie Lengard; Wold, Jens Petter; Dinnella, Caterina

    2017-09-01

    The density of fungiform papillae (FPD) on the human tongue is currently taken as index for responsiveness to oral chemosensory stimuli. Visual analysis of digital tongue picture and manual counting by trained operators represents the most popular technique for FPD assessment. Methodological issues mainly due to operator bias are considered among factors accounting for the uncertainty about the relationships between FPD and responsiveness to chemosensory stimuli. The present study describes a novel automated method to count fungiform papillae (FP) from image analysis of tongue pictures. The method was applied to tongue pictures from 133 subjects. Taking the manual count as reference method, a partial least squares regression model was developed to predict FPD from tongue automated analysis output. FPD from manual and automated count showed the same normal distribution and comparable descriptive statistic values. Consistent subject classifications as low and high FPD were obtained according to the median values from manual and automated count. The same results on the effect of FPD variation on taste perception were obtained both using predicted and counted values. The proposed method overcomes count uncertainties due to researcher bias in manual counting and is suited for large population studies. Additional information is provided such as FP size class distribution which would help for a better understanding of the relationships between FPD variation and taste functions. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Association of platelet count with residual thrombus in the myocardial infarct-related coronary artery among patients treated with fibrinolytic therapy for ST-segment elevation acute myocardial infarction.

    PubMed

    Turakhia, Minang P; Murphy, Sabina A; Pinto, Tina L; Antman, Elliott M; Giugliano, Robert P; Cannon, Christopher P; Braunwald, Eugene; Gibson, C Michael

    2004-12-01

    A higher platelet count is independently associated with the presence of residual thrombus in the infarct-related artery after administration of fibrinolytic therapy, even after multivariate adjustment.

  15. Effects of sodium citrate and acid citrate dextrose solutions on cell counts and growth factor release from equine pure-platelet rich plasma and pure-platelet rich gel.

    PubMed

    Giraldo, Carlos E; Álvarez, María E; Carmona, Jorge U

    2015-03-14

    There is a lack information on the effects of the most commonly used anticoagulants for equine platelet rich plasmas (PRPs) elaboration on cell counts and growth factor release from platelet rich gels (PRGs). The aims of this study were 1) to compare the effects of the anticoagulants sodium citrate (SC), acid citrate dextrose solution A (ACD-A) and ACD-B on platelet (PLT), leukocyte (WBC) and on some parameters associated to platelet activation including mean platelet volume (MPV) and platelet distribution width (PDW) between whole blood, pure PRP (P-PRP) and platelet-poor plasma (PPP); 2) to compare transforming growth factor beta 1 (TGF-β(1)) and platelet-derived growth factor isoform BB (PDGF-BB) concentrations in supernatants from pure PRG (P-PRG), platelet-poor gel (PPG), P-PRP lysate (positive control) and plasma (negative control); 3) to establish the possible correlations between all the studied cellular and molecular parameters. In all cases the three anticoagulants produced P-PRPs with significantly higher PLT counts compared with whole blood and PPP. The concentrations of WBCs were similar between P-PRP and whole blood, but significantly lower in PPP. The type of anticoagulant did not significantly affect the cell counts for each blood component. The anticoagulants also did not affect the MPV and PDW parameters. Independently of the anticoagulant used, all blood components presented significantly different concentrations of PDGF-BB and TGF-β(1). The highest growth factor (GF) concentrations were observed from P-PRP lysates, followed by PRG supernatants, PPP lysates, PPG supernatants and plasma. Significant correlations were observed between PLT and WBC counts (ρ = 0.80), PLT count and TGF-β(1) concentration (ρ = 0.85), PLT count and PDGF-BB concentration (ρ = 0.80) and PDGF-BB and TGF-β(1) concentrations (ρ = 0.75). The type of anticoagulant was not correlated with any of the variables evaluated. The anticoagulants did not

  16. Thrombocytopenia and platelet transfusion in the neonate.

    PubMed

    Cremer, Malte; Sallmon, Hannes; Kling, Pamela J; Bührer, Christoph; Dame, Christof

    2016-02-01

    Neonatal thrombocytopenia is widespread in preterm and term neonates admitted to neonatal intensive care units, with up to one-third of infants demonstrating platelet counts <150 × 10(9)/L. Thrombocytopenia may arise from maternal, placental or fetal/neonatal origins featuring decreased platelet production, increased consumption, or both mechanisms. Over the past years, innovations in managing neonatal thrombocytopenia were achieved from prospectively obtained clinical data on thrombocytopenia and bleeding events, animal studies on platelet life span and production rate and clinical use of fully automated measurement of reticulated platelets (immature platelet fraction). This review summarizes the pathophysiology of neonatal thrombocytopenia, current management including platelet transfusion thresholds and recent developments in megakaryopoietic agents. Furthermore, we propose a novel index score for bleeding risk in thrombocytopenic neonates to facilitate clinician's decision-making when to transfuse platelets.

  17. Fully automated detection of the counting area in blood smears for computer aided hematology.

    PubMed

    Rupp, Stephan; Schlarb, Timo; Hasslmeyer, Erik; Zerfass, Thorsten

    2011-01-01

    For medical diagnosis, blood is an indispensable indicator for a wide variety of diseases, i.e. hemic, parasitic and sexually transmitted diseases. A robust detection and exact segmentation of white blood cells (leukocytes) in stained blood smears of the peripheral blood provides the base for a fully automated, image based preparation of the so called differential blood cell count in the context of medical laboratory diagnostics. Especially for the localization of the blood cells and in particular for the segmentation of the cells it is necessary to detect the working area of the blood smear. In this contribution we present an approach for locating the so called counting area on stained blood smears that is the region where cells are predominantly separated and do not interfere with each other. For this multiple images of a blood smear are taken and analyzed in order to select the image corresponding to this area. The analysis involves the computation of an unimodal function from image content that serves as indicator for the corresponding image. This requires a prior segmentation of the cells that is carried out by a binarization in the HSV color space. Finally, the indicator function is derived from the number of cells and the cells' surface area. Its unimodality guarantees to find a maximum value that corresponds to the counting areas image index. By this, a fast lookup of the counting area is performed enabling a fully automated analysis of blood smears for medical diagnosis. For an evaluation the algorithm's performance on a number of blood smears was compared with the ground truth information that has been defined by an adept hematologist.

  18. The effect of the perfluorocarbon emulsion Oxycyte on platelet count and function in the treatment of decompression sickness in a swine model.

    PubMed

    Cronin, William A; Senese, Angela L; Arnaud, Francoise G; Regis, David P; Auker, Charles R; Mahon, Richard T

    2016-09-01

    Decompression from elevated ambient pressure is associated with platelet activation and decreased platelet counts. Standard treatment for decompression sickness (DCS) is hyperbaric oxygen therapy. Intravenous perfluorocarbon (PFC) emulsion is a nonrecompressive therapy being examined that improves mortality in animal models of DCS. However, PFC emulsions are associated with a decreased platelet count. We used a swine model of DCS to study the effect of PFC therapy on platelet count, function, and hemostasis. Castrated male swine (n = 50) were fitted with a vascular port, recovered, randomized, and compressed to 180 feet of sea water (fsw) for 31 min followed by decompression at 30 fsw/min. Animals were observed for DCS, administered 100% oxygen, and treated with either emulsified PFC Oxycyte (DCS-PFC) or isotonic saline (DCS-NS). Controls underwent the same procedures, but were not compressed (Sham-PFC and Sham-NS). Measurements of platelet count, thromboelastometry, and coagulation were obtained 1 h before compression and 1, 24, 48, 96, 168 and 192 h after treatment. No significant changes in normalized platelet counts were observed. Prothrombin time was elevated in DCS-PFC from 48 to 192 h compared with DCS-NS, and from 96 to 192 h compared with Sham-PFC. Normalized activated partial thromboplastin time was also elevated in DCS-PFC from 168 to 192 h compared with Sham-PFC. No bleeding events were noted. DCS treated with PFC (Oxycyte) does not impact platelet numbers, whole blood clotting by thromboelastometry, or clinical bleeding. Late changes in prothrombin time and activated partial thromboplastin time associated with PFC use in both DCS therapy and controls warrant further investigation.

  19. Prognostic Factors of the Efficacy of High-dose Corticosteroid Therapy in Hemolysis, Elevated Liver Enzymes, and Low Platelet Count Syndrome During Pregnancy: A Meta-analysis.

    PubMed

    Yang, Li; Ren, Chenchen; Mao, Minhong; Cui, Shihong

    2016-03-01

    The aim of this study was to identify the factors which can affect the efficacy of corticosteroid (CORT) therapy in the management of hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. Research articles reporting the efficacy of CORT therapy to HELLP syndrome patients were searched in several electronic databases including EMBASE, Google Scholar, Ovid SP, PubMed, and Web of Science. Study selection was based on predefined eligibility criteria. Efficacy was defined by the changes from baseline in HELLP syndrome indicators after CORT therapy. Meta-analyses were carried out with Stata software. Data of 778 CORT-treated HELLP syndrome patients recruited in 22 studies were used in the analyses. Corticosteroid treatment to HELLP syndrome patients was associated with significant changes from baseline in platelet count; serum levels of aspartate aminotransaminase, alanine transaminase, and lactic dehydrogenase (LDH); mean blood pressure; and urinary output. Lower baseline platelet count predicted higher change in platelet count after CORT therapy. Lower baseline platelet count and lower baseline urinary output predicted greater changes in LDH levels after CORT therapy. There was also an inverse relationship between the change from baseline in LDH levels and intensive care duration. Higher CORT doses were associated with greater declines in the aspartate aminotransaminase, alanine transaminase, and LDH levels. Incidence of cesarean delivery was inversely associated with the gestation age. The percentage of nulliparous women had a positive association with the intensive care stay duration. High-dose CORT therapy to HELLP syndrome patients provides benefits in improving disease markers and reducing intensive care duration, especially in cases such as mothers with much lower baseline platelet count and LDH levels.

  20. Synthetic materials for platelet quality control.

    PubMed

    Lott, J A; Hartzell, R K; Longberry, J

    1983-01-01

    At present, the quality control of platelet counting by semi-automated and automated methods does not meet ideal standards. Controls prepared from human or animal platelets have limited stability, and some synthetic platelet controls that are available do not have the size distribution of fresh platelets. The platelet control materials described here are wholly synthetic; however, their particle size distribution is like that of normal human platelets, and the dispersing medium has the viscosity and surface tension of plasma. Two types of products are described. The first type are dilutions of the synthetic platelets which are handled like 3000-fold dilutions of platelet-rich plasma and are intended for direct use on instruments like the Coulter ZBI. The two dilution levels gave counts of about 50,000 and 200,000/microL on the Coulter ZBI and were found to be stable for at least 30 days at - 20C, 4C, and 37C, and at least eight months at 25C. The second type of product is handled like whole blood and is intended for direct use on instruments like the Coulter Model S-Plus. This product gave counts of about 200,000/microL and was found to be stable for at least 120 days at - 20C, 4C, 25C, and 37C. Freezing at - 20C produced some aggregates that dispersed after thawing and standing for several days prior to testing.

  1. Platelet-induced thrombin generation by the calibrated automated thrombogram assay is increased in patients with essential thrombocythemia and polycythemia vera.

    PubMed

    Panova-Noeva, Marina; Marchetti, Marina; Spronk, Henri Maria; Russo, Laura; Diani, Erika; Finazzi, Guido; Finazzi, Good; Salmoiraghi, Silvia; Rambaldi, Alessandro; Rambaldi, Aueesandrd; Barbui, Tiziano; Barbui, Titiano; Ten Cate, Hugo; Ten Cate, Huao; Falanga, Anna

    2011-04-01

    The platelet contribution to the thrombophilic state of patients with myeloproliferative neoplasms (MPNs), i.e., essential thrombocythemia (ET) and polycythemia vera (PV), remains uncertain. In this study we aimed to characterize the thrombin generation (TG) potential expressed by platelets from these subjects, compare it to normal platelets, and identify what factors might be responsible for platelet TG. In a group of 140 MPN patients (80 ET and 60 PV) and 72 healthy subjects, we measured the global procoagulant potential of platelet-rich plasma (PRP) utilizing the TG assay by the calibrated automated thrombogram (CAT). To characterize the procoagulant contribution of platelets in PRP, the TG of both isolated platelets and platelet-poor plasma was measured, and the platelet surface expression of TF was determined. Finally, the activation status of platelets was assessed by the levels of P-selectin expressed on platelet surface. MPN patients had significantly increased PRP and isolated platelet TG potential compared to controls. This was associated to the occurrence of platelet activation. Patients carriers of the JAK2V617F mutation showed the highest values of TG and platelet surface TF and P-selectin. Platelet TG potential was significantly lower in hydroxyurea(HU) compared to non-HU-treated patients and was lowest in HU-treated JAK2V617F carriers. In subjects not receiving HU, platelet TG significantly increased by JAK2V617F allele burden increment (P < 0.05).This study demonstrates a platelet-dependent form of hypercoagulability in MPN patients, particularly in those carriers of the JAK2V617F mutation. The cytoreductive therapy with HU significantly affects this prothrombotic phenotype.

  2. Evaluation of Cell Counting in Body Fluids: Comparison of Two Automated Hematology Analyzers with Manual Microscopy.

    PubMed

    Genc, Sema; Dervisoglu, Elmire; Omer, Dilara; Kucukates, Emine; Omer, Beyhan; Ademoglu, Evin

    2016-12-01

    Manual microscopic analysis (MMA) of body fluids has been widely replaced by automated systems. The aim of this study was to assess the performances of the Sysmex XN-1000 (XN-1000) and UniCel DxH800 (DxH800) for body fluid analysis and compare their results with MMA and with each other. Red blood cell (RBC), WBC and WBC-differential counts of 142 body fluid samples (7 cerebrospinal, 28 pleural, 107 ascitic fluids) were performed using DxH800, XN-1000, and MMA. The within-run and between-days CVs% were lower than 10% for both systems except MONO of DxH800. Both analyzers demonstrated good linearity and minimal carry-over. The comparison of the XN-1000 and DxH800 with manual counting and each other revealed good correlation (r > 0.90 for both). Automated systems introduce standardized and accurate performances to analyze biologic fluids. They are also beneficial for reducing turn-around time and laboratory costs.

  3. Clinical significance of the preoperative platelet count and platelet-to-lymphocyte ratio (PLT-PLR) in patients with surgically resected non-small cell lung cancer

    PubMed Central

    Kim, Seok-Hyun; Lee, Hyoun Wook; Go, Se-Il; Lee, Soon Il; Lee, Gyeong-Won

    2016-01-01

    Background The aim of this study was to assess the prognostic significance of the preoperative platelet count (PLT) and platelet-to-lymphocyte ratio (PLR) in patients with surgically resected non-small-cell lung cancer (NSCLC). Patients and Methods We retrospectively reviewed 202 patients treated for NSCLC between January 2002 and December 2007. Preoperative PLT and PLR scores were calculated using data obtained at the time of admission. Patients were assigned a PLT-PLR score of 0, 1, or 2 based upon the presence of thrombocytosis, an elevated PLR, or both. Results Patients with a PLT-PLR score of 2 had a significantly lower median overall survival (OS) [12.715 mo; 95% confidence interval (CI) 1.215-24.215] when compared with patients with PLT-PLR scores of 1 (52.238 mo; 95% CI 17.062-87.414, p = 0.002) or 0 (not reached, p < 0.001). Relapse-free survival (RFS) was also significantly decreased in patients with a PLT-PLR score of 2 (10.107 mo; 95% CI 3.388-16.826) relative to patients with a PLT-PLR score of 1 (27.214 mo; 95% CI 0-56.253, p = 0.002) or 0 (58.893 mo; 95% CI 32.938-84.848, p < 0.001). In multivariate analysis, a PLT-PLR score of 2 was an independent prognostic factor for poor OS (hazard ratio (HR) 3.473; 95% CI 1.765-6.835, p < 0.001) and RFS (HR 2.286; 95% CI 1.243-4.206, p = 0.008) compared with a PLT-PLR score of 0. Conclusions Preoperative PLT-PLR scores can be useful for predicting disease prognosis in patients with surgically resected NSCLC. Further large prospective studies will be necessary to validate our findings. PMID:27105529

  4. Corticosteroid Therapy for Management of Hemolysis, Elevated Liver Enzymes, and Low Platelet Count (HELLP) Syndrome: A Meta-Analysis.

    PubMed

    Mao, Minhong; Chen, Chen

    2015-12-03

    BACKGROUND Hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome is a severe condition of pregnancy that is associated with significant morbidity and mortality. Corticoteroid (CORT) therapy is common in the management of HELLP syndrome. This study evaluates the efficacy of CORT therapy to patients with HELLP Syndrome. MATERIAL AND METHODS A literature search was carried out in multiple electronic databases. Meta-analyses of means difference and odds ratio were carried under the random-effects model. RESULTS Fifteen studies (675 CORT treated and 787 control HELLP patients) were included. CORT treatment significantly improved platelet count (mean difference between CORT treated and controls in changes from baseline, MD: 38.08 [15.71, 60.45]×109; p=0.0009), lactic dehydrogenase (LDH) levels (MD: -440 [-760, -120] IU/L; p=0.007), and alanine aminotransferase (ALT) levels (MD: -143.34 [-278.69, -7.99] IU/L; p=0.04) but the decrease in aspartate aminotransferase (AST) levels was not statistically significant (MD: -48.50 [-114.32, 17.32] IU/L; p=0.15). Corticosteroid treatment was also associated with significantly less blood transfusion rate (odds ratio, OR: 0.42 [0.24, 0.76]; p=0.004) and hospital/ICU stay (MD: -1.79 [-3.54, -0.05] days; p=0.04). Maternal mortality (OR: 1.27 [0.45, 3.60]; p=0.65), birth weight (MD: 0.09 [-0.11, 0.28]; p=0.38) and the prevalence of morbid conditions (OR: 0.79 [0.58, 1.08]; p=0.14) did not differ significantly between both groups. CONCLUSIONS Corticosteroid administration to HELLP patients improves platelet count, and the serum levels of LDH and ALT, and reduces hospital/ICU stay and blood transfusion rate, but is not significantly associated with better maternal mortality and overall morbidity.

  5. Risk factors for adverse maternal outcomes among women with HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome.

    PubMed

    Haddad, B; Barton, J R; Livingston, J C; Chahine, R; Sibai, B M

    2000-08-01

    This study was undertake to determine risk factors for adverse maternal outcomes among women with HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Maternal medical records of pregnancies complicated by HELLP syndrome managed between July 1, 1992, and April 30, 1999, were reviewed. Risk factors evaluated included maternal age, parity, race, previous preeclampsia, chronic hypertension, gestational age at diagnosis, mean arterial blood pressure, nadir blood platelet count (<50,000 cells/microL vs > or =50,000 cells/microL), and peak serum levels of aspartate aminotransferase and lactate dehydrogenase. Maternal outcome variables analyzed included eclampsia, abruptio placentae, disseminated intravascular coagulopathy, pulmonary edema, pleural effusion, ascites, acute renal failure, liver hematoma, need for transfusion of blood products, cesarean delivery, and death. Statistical analysis was performed with the Student t test, the chi(2) test, and logistic regression analysis. A total of 183 women with HELLP syndrome were studied. Eclampsia was present in 6%, abruptio placentae was present in 10%, and disseminated intravascular coagulopathy was present in 8%. Forty-one women (22%) required transfusion of blood products. Incidence of eclampsia significantly decreased with increasing gestational age, from 16% at < or =28 weeks' gestation to 3% at >32 weeks' gestation (P <.05) and was higher among African American patients than among white patients (12% vs 3%; P <.05). Logistic regression analysis showed an independent relationship between eclampsia and race (P <.05). Incidence of abruptio placentae was higher among women with previous preeclampsia than among women without this clinical history (26% vs 5%; P <.05). Disseminated intravascular coagulopathy was significantly associated with abruptio placentae (P <.0001) and acute renal failure (P <.0001). A nadir platelet count of <50, 000/microL, a peak serum aspartate aminotransferase level of >150

  6. Automated characterization and counting of Ki-67 protein for breast cancer prognosis: A quantitative immunohistochemistry approach.

    PubMed

    Mungle, Tushar; Tewary, Suman; Arun, Indu; Basak, Bijan; Agarwal, Sanjit; Ahmed, Rosina; Chatterjee, Sanjoy; Maity, Asok Kumar; Chakraborty, Chandan

    2017-02-01

    Ki-67 protein expression plays an important role in predicting the proliferative status of tumour cells and deciding the future course of therapy in breast cancer. Immunohistochemical (IHC) determination of Ki-67 score or labelling index, by estimating the fraction of Ki67 positively stained tumour cells, is the most widely practiced method to assess tumour proliferation (Dowsett et al. 2011). Accurate manual counting of these cells (specifically nuclei) due to complex and dense distribution of cells, therefore, becomes critical and presents a major challenge to pathologists. In this paper, we suggest a hybrid clustering algorithm to quantify the proliferative index of breast cancer cells based on automated counting of Ki-67 nuclei. The proposed methodology initially pre-processes the IHC images of Ki-67 stained slides of breast cancer. The RGB images are converted to grey, L*a*b*, HSI, YCbCr, YIQ and XYZ colour space. All the stained cells are then characterized by two stage segmentation process. Fuzzy C-means quantifies all the stained cells as one cluster. The blue channel of the first stage output is given as input to k-means algorithm, which provides separate cluster for Ki-67 positive and negative cells. The count of positive and negative nuclei is used to calculate the F-measure for each colour space. A comparative study of our work with the expert opinion is studied to evaluate the error rate. The positive and negative nuclei detection results for all colour spaces are compared with the ground truth for validation and F-measure is calculated. The F-measure for L*a*b* colour space (0.8847) provides the best statistical result as compared to grey, HSI, YCbCr, YIQ and XYZ colour space. Further, a study is carried out to count nuclei manually and automatically from the proposed algorithm with an average error rate of 6.84% which is significant. The study provides an automated count of positive and negative nuclei using L*a*b*colour space and hybrid

  7. Fast automated yeast cell counting algorithm using bright-field and fluorescence microscopic images

    PubMed Central

    2013-01-01

    Background The faithful determination of the concentration and viability of yeast cells is important for biological research as well as industry. To this end, it is important to develop an automated cell counting algorithm that can provide not only fast but also accurate and precise measurement of yeast cells. Results With the proposed method, we measured the precision of yeast cell measurements by using 0%, 25%, 50%, 75% and 100% viability samples. As a result, the actual viability measured with the proposed yeast cell counting algorithm is significantly correlated to the theoretical viability (R2 = 0.9991). Furthermore, we evaluated the performance of our algorithm in various computing platforms. The results showed that the proposed algorithm could be feasible to use with low-end computing platforms without loss of its performance. Conclusions Our yeast cell counting algorithm can rapidly provide the total number and the viability of yeast cells with exceptional accuracy and precision. Therefore, we believe that our method can become beneficial for a wide variety of academic field and industries such as biotechnology, pharmaceutical and alcohol production. PMID:24215650

  8. High plasma fibrinogen concentration and platelet count unfavorably impact survival in non-small cell lung cancer patients with brain metastases.

    PubMed

    Zhu, Jian-Fei; Cai, Ling; Zhang, Xue-Wen; Wen, Yin-Sheng; Su, Xiao-Dong; Rong, Tie-Hua; Zhang, Lan-Jun

    2014-02-01

    High expression of fibrinogen and platelets are often observed in non-small cell lung cancer (NSCLC) patients with local regional or distant metastasis. However, the role of these factors remains unclear. The aims of this study were to evaluate the prognostic significance of plasma fibrinogen concentration and platelet count, as well as to determine the overall survival of NSCLC patients with brain metastases. A total of 275 NSCLC patients with brain metastasis were enrolled into this study. Univariate analysis showed that high plasma fibrinogen concentration was associated with age≥65 years (P = 0.011), smoking status (P = 0.009), intracranial symptoms (P = 0.022), clinical T category (P = 0.010), clinical N category (P = 0.003), increased partial thromboplastin time (P < 0.001), and platelet count (P < 0.001). Patients with low plasma fibrinogen concentration demonstrated longer overall survival compared with those with high plasma fibrinogen concentration (median, 17.3 months versus 11.1 months; P≤0.001). A similar result was observed for platelet counts (median, 16.3 months versus 11.4 months; P = 0.004). Multivariate analysis showed that both plasma fibrinogen concentration and platelet count were independent prognostic factors for NSCLC with brain metastases (R2 = 1.698, P < 0.001 and R2 = 1.699, P < 0.001, respectively). Our results suggest that high plasma fibrinogen concentration and platelet count indicate poor prognosis for NSCLC patients with brain metastases. Thus, these two biomarkers might be independent prognostic predictors for this subgroup of NSCLC patients.

  9. Procoagulant and platelet-derived microvesicle absolute counts determined by flow cytometry correlates with a measurement of their functional capacity

    PubMed Central

    Ayers, Lisa; Harrison, Paul; Kohler, Malcolm; Ferry, Berne

    2014-01-01

    Background Flow cytometry is the most commonly used technology to measure microvesicles (MVs). Despite reported limitations of this technique, MV levels obtained using conventional flow cytometry have yielded many clinically relevant findings, such as associations with disease severity and ability to predict clinical outcomes. This study aims to determine if MV enumeration by flow cytometry correlates with a measurement of their functional capacity, as this may explain how flow cytometry generates clinically relevant results. Methods One hundred samples from healthy individuals and patients with obstructive sleep apnoea were analysed by conventional flow cytometry (FACSCalibur) and by three functional MV assays: Zymuphen MP-activity in which data were given as phosphatidylserine equivalent, STA® Phospholipid Procoag Assay expressed as clotting time and Endogenous Thrombin Potential (ETP) reflecting in vitro thrombin generation. Correlations were determined by Spearman correlation. Results Absolute counts of lactadherin+ procoagulant MVs generated by flow cytometry weakly correlated with the results obtained from the Zymuphen MP-activity (r=0.5370, p<0.0001); correlated with ETP (r=0.7444, p<0.0001); negatively correlated with STA® Phospholipid Procoag Assay clotting time (−0.7872, p<0.0001), reflecting a positive correlation between clotting activity and flow cytometry. Levels of Annexin V+ procoagulant and platelet-derived MVs were also associated with functional assays. Absolute counts of MVs derived from other cell types were not correlated with the functional results. Conclusions Quantitative results of procoagulant and platelet-derived MVs from conventional flow cytometry are associated with the functional capability of the MVs, as defined by three functional MV assays. Flow cytometry is a valuable technique for the quantification of MVs from different cellular origins; however, a combination of several analytical techniques may give the most comprehensive

  10. Automated parasite faecal egg counting using fluorescence labelling, smartphone image capture and computational image analysis.

    PubMed

    Slusarewicz, Paul; Pagano, Stefanie; Mills, Christopher; Popa, Gabriel; Chow, K Martin; Mendenhall, Michael; Rodgers, David W; Nielsen, Martin K

    2016-07-01

    Intestinal parasites are a concern in veterinary medicine worldwide and for human health in the developing world. Infections are identified by microscopic visualisation of parasite eggs in faeces, which is time-consuming, requires technical expertise and is impractical for use on-site. For these reasons, recommendations for parasite surveillance are not widely adopted and parasite control is based on administration of rote prophylactic treatments with anthelmintic drugs. This approach is known to promote anthelmintic resistance, so there is a pronounced need for a convenient egg counting assay to promote good clinical practice. Using a fluorescent chitin-binding protein, we show that this structural carbohydrate is present and accessible in shells of ova of strongyle, ascarid, trichurid and coccidian parasites. Furthermore, we show that a cellular smartphone can be used as an inexpensive device to image fluorescent eggs and, by harnessing the computational power of the phone, to perform image analysis to count the eggs. Strongyle egg counts generated by the smartphone system had a significant linear correlation with manual McMaster counts (R(2)=0.98), but with a significantly lower coefficient of variation (P=0.0177). Furthermore, the system was capable of differentiating equine strongyle and ascarid eggs similar to the McMaster method, but with significantly lower coefficients of variation (P<0.0001). This demonstrates the feasibility of a simple, automated on-site test to detect and/or enumerate parasite eggs in mammalian faeces without the need for a laboratory microscope, and highlights the potential of smartphones as relatively sophisticated, inexpensive and portable medical diagnostic devices. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  11. FTO first intron rs1558902 variant and platelets count in white middle-aged women: prague pre- and post-menopausal females (3PMFs) study.

    PubMed

    Hubacek, Jaroslav A; Dlouha, Dana; Lanska, Vera; Stavek, Petr; Pagacova, Libuse; Kralova-Lesna, Ivana; Pitha, Jan

    2013-02-01

    The polymorphisms within the FTO gene play an important role in the genetic determination of body weight and body mass index and have been associated with cardiovascular disease, but the causal mechanism is still a matter of debate. The possible effect on the platelet count as a marker of hemocoagulation status as a possible cardiovascular risk factor was suggested in Japanese population. We have analyzed both rs1558902 FTO polymorphism (T > A) and platelet counts in the Prague Pre and Post Menopausal Females (3PMFs) study, including those of 669 women (mean age, 55.7 ± 2.7 years). The frequencies of the FTO genotypes were similar to other populations (TT, 30.4%; TA, 48.1%; and AA, 21.5%). We have not detected a significant association between the FTO rs1558902 variant and platelet counts in white women (TT, 242 ± 55 × 10; TA, 246 ± 67 × 10; and AA, 247 ± 55 × 10; F[2.642] = 0.30, P = 0.75). At least in white persons, platelet count seems not to be a link between the FTO variation and risk of cardiovascular disease.

  12. Current automated 3D cell detection methods are not a suitable replacement for manual stereologic cell counting.

    PubMed

    Schmitz, Christoph; Eastwood, Brian S; Tappan, Susan J; Glaser, Jack R; Peterson, Daniel A; Hof, Patrick R

    2014-01-01

    Stereologic cell counting has had a major impact on the field of neuroscience. A major bottleneck in stereologic cell counting is that the user must manually decide whether or not each cell is counted according to three-dimensional (3D) stereologic counting rules by visual inspection within hundreds of microscopic fields-of-view per investigated brain or brain region. Reliance on visual inspection forces stereologic cell counting to be very labor-intensive and time-consuming, and is the main reason why biased, non-stereologic two-dimensional (2D) "cell counting" approaches have remained in widespread use. We present an evaluation of the performance of modern automated cell detection and segmentation algorithms as a potential alternative to the manual approach in stereologic cell counting. The image data used in this study were 3D microscopic images of thick brain tissue sections prepared with a variety of commonly used nuclear and cytoplasmic stains. The evaluation compared the numbers and locations of cells identified unambiguously and counted exhaustively by an expert observer with those found by three automated 3D cell detection algorithms: nuclei segmentation from the FARSIGHT toolkit, nuclei segmentation by 3D multiple level set methods, and the 3D object counter plug-in for ImageJ. Of these methods, FARSIGHT performed best, with true-positive detection rates between 38 and 99% and false-positive rates from 3.6 to 82%. The results demonstrate that the current automated methods suffer from lower detection rates and higher false-positive rates than are acceptable for obtaining valid estimates of cell numbers. Thus, at present, stereologic cell counting with manual decision for object inclusion according to unbiased stereologic counting rules remains the only adequate method for unbiased cell quantification in histologic tissue sections.

  13. Feasibility and usefulness of self-assessment of bleeding in patients with haematological malignancies, and the association between platelet count and bleeding.

    PubMed

    Stanworth, S J; Dyer, C; Casbard, A; Murphy, M F

    2006-07-01

    The aim of this study was to evaluate the collection of daily prospective information about bleeding outcomes in patients with thrombocytopenia, including information obtained by patient self-assessment. Consecutive patients with haematological malignancies were enrolled in a study of bleeding data collection during the period of thrombocytopenia. A short educational session and information sheet was designed for self-assessment. Platelet counts and all transfusions were recorded daily. Bleeding scores were translated into World Health Organization (WHO) bleeding grades. Nineteen patients were included in the study. Four-hundred and ten days of thrombocytopenia were eligible for assessment of bleeds. Self-assessment was feasible, as defined by the total proportion of days on which self-assessment was completed (70%, 288 thrombocytopenic days). There was 86% agreement between bleeding data collected by self-assessment and by medical examination using a structured assessment form. Examples of discrepancies included the duration of petechiae/bruises and the reporting of minor bleeding. There was no evidence for an association between patients' morning platelet count and daily WHO bleeding grade. The incidences of WHO grade 1 and grade 2 bleeding on days with platelet counts < or = 10 x 10(9)/l, 11-20 x 10(9)/l, and > 20 x 10(9)/l were similar and did not reveal higher rates of bleeding at lower counts. Patient self-assessment can help to support comprehensive daily prospective monitoring of bleeding, specifically facilitating data collection following hospital discharge. The discrepancies between self-assessment and medical examination highlight the need to develop a validated international assessment tool. The association among platelet count, risk of bleeding and role of prophylactic platelet transfusions needs further evaluation in larger prospective trials.

  14. Acute leukemia detection rate by automated blood count parameters and peripheral smear review.

    PubMed

    Rabizadeh, E; Pickholtz, I; Barak, M; Isakov, E; Zimra, Y; Froom, P

    2015-02-01

    It is unclear what minimal criteria will identify all new cases of acute leukemia in adults in various settings. To determine the adult acute leukemia detection rate of the various criteria, we recorded complete blood count (CBC) test results from consecutive patients with leukemia (130 hospitalized patients and 96 outpatients) and from consecutive patients without leukemia (34,827 hospitalized and 33,695 outpatients). Basic criteria for a reflex review (hemoglobin, platelets, and a five-part differential) detected 91% of new hospital leukemia patients (118 of 130) compared to 75% (72 of 96) outpatients. No cases were missed if we did reflex testing when there was either one of the basic criteria or an increased proportion of large unstained cells (LUC), but five cases were missed using the blast flag instead of the LUC. Adding the LUC to basic criteria resulted in the detection of all cases of acute leukemia. The cost of detection of one case of acute leukemia was 1029 and 425 peripheral smear reviews in hospital and outpatients, respectively. We conclude that basic criteria available on most hematology analyzers along with the LUC identify all adult patients with acute leukemia in both hospital and outpatient settings with minimal peripheral smear review rates. © 2014 John Wiley & Sons Ltd.

  15. Automated system for sampling, counting, and biological analysis of rotifer populations.

    PubMed

    Stelzer, Claus-Peter

    2009-12-01

    Zooplankton organisms with short generation times, such as rotifers, are ideal models to study general ecological and evolutionary questions on the population level, because meaningful experiments can often be completed within a couple of weeks. Yet biological analysis of such populations is often extremely time consuming, owing to abundance estimation by counting, measuring body size, or determining the investment into sexual versus asexual reproduction. An automated system for sampling and analyzing experimental rotifer populations is described. It relies on image analysis of digital photographs taken from subsamples of the culture. The system works completely autonomously for up to several weeks and can sample up to 12 cultures at time intervals down to a few hours. It allows quantitative analysis of female population density at a precision equivalent to that of conventional methods (i.e., manual counts of samples fixed in Lugol solution), and it can also recognize males, which allows detecting temporal variation of sexual reproduction in such cultures. Another parameter that can be automatically measured with the image analysis system is female body size. This feature may be useful for studies of population productivity and/or in competition experiments with clones of different body size. In this article, I describe the basic setup of the system and tests on the efficiency of data collection, and show some example data sets on the population dynamics of different strains of the rotifer Brachionus calyciflorus.

  16. Design of an Automated-Counting System of Cell Micronuclei in Micrographs

    NASA Astrophysics Data System (ADS)

    Lozano, A. V.; Márquez, J. A.; Buenfil, A. E.; Gonsebatt, M. E.

    2004-09-01

    We developed and tested a system for the automatic analysis of cell images in order to identify and count micronuclei configurations in digital images from a microscope. The presence of micronuclei has been used as an indicator of DNA damage, and a fast automated analysis may be suitable for early cancer detection, for example. We describe in this work the image-processing protocol and system comprising: acquisition, color normalization, contrast enhancement, color-background removing, color segmentation, mathematical-morphology filtering and restoration, morphometry, feature extraction and analysis, and counting. Among the morphological features used for discriminating micronuclei configurations, we tested compactness, area ratios and separation of selected features (ideally, a nucleus and one or more micronuclei). Among the mathematical-morphology techniques, we used for instance a modified watershed segmentation algorithm for separating touching features. We present our results on several images, the evaluation and performance of each step, and the main problems we solved by using several techniques from mathematical morphology and color-image processing.

  17. Automated system for sampling, counting, and biological analysis of rotifer populations

    PubMed Central

    Stelzer, Claus-Peter

    2010-01-01

    Zooplankton organisms with short generation times, such as rotifers, are ideal models to study general ecological and evolutionary questions on the population level, because meaningful experiments can often be completed within a couple of weeks. Yet biological analysis of such populations is often extremely time consuming, owing to abundance estimation by counting, measuring body size, or determining the investment into sexual versus asexual reproduction. An automated system for sampling and analyzing experimental rotifer populations is described. It relies on image analysis of digital photographs taken from subsamples of the culture. The system works completely autonomously for up to several weeks and can sample up to 12 cultures at time intervals down to a few hours. It allows quantitative analysis of female population density at a precision equivalent to that of conventional methods (i.e., manual counts of samples fixed in Lugol solution), and it can also recognize males, which allows detecting temporal variation of sexual reproduction in such cultures. Another parameter that can be automatically measured with the image analysis system is female body size. This feature may be useful for studies of population productivity and/or in competition experiments with clones of different body size. In this article, I describe the basic setup of the system and tests on the efficiency of data collection, and show some example data sets on the population dynamics of different strains of the rotifer Brachionus calyciflorus. PMID:21151824

  18. Automated imaging, identification, and counting of similar cells from digital hologram reconstructions.

    PubMed

    Mihailescu, Mona; Scarlat, Mihaela; Gheorghiu, Alexandru; Costescu, Julia; Kusko, Mihai; Paun, Irina Alexandra; Scarlat, Eugen

    2011-07-10

    This paper presents our method, which simultaneously combines automatic imaging, identification, and counting with the acquisition of morphological information for at least 1000 blood cells from several three-dimensional images of the same sample. We started with seeking parameters to differentiate between red blood cells that are similar but different with respect to their development stage, i.e., mature or immature. We highlight that these cells have different diffractive patterns with complementary central intensity distribution in a given plane along the propagation axis. We use the Fresnel approximation to simulate propagation through cells modeled as spheroid-shaped phase objects and to find the cell property that has the dominant influence on this behavior. Starting with images obtained in the reconstruction step of the digital holographic microscopy technique, we developed a code for automated simultaneous individual cell image separation, identification, and counting, even when the cells are partially overlapped on a slide, and accurate measuring of their morphological features. To find the centroids of each cell, we propose a method based on analytical functions applied at threshold intervals. Our procedure separates the mature from the immature red blood cells and from the white blood cells through a decision based on gradient and radius values. © 2011 Optical Society of America

  19. Automated imaging, identification, and counting of similar cells from digital hologram reconstructions

    NASA Astrophysics Data System (ADS)

    Mihailescu, Mona; Scarlat, Mihaela; Gheorghiu, Alexandru; Costescu, Julia; Kusko, Mihai; Paun, Irina Alexandra; Scarlat, Eugen

    2011-07-01

    This paper presents our method, which simultaneously combines automatic imaging, identification, and counting with the acquisition of morphological information for at least 1000 blood cells from several three-dimensional images of the same sample. We started with seeking parameters to differentiate between red blood cells that are similar but different with respect to their development stage, i.e., mature or immature. We highlight that these cells have different diffractive patterns with complementary central intensity distribution in a given plane along the propagation axis. We use the Fresnel approximation to simulate propagation through cells modeled as spheroid-shaped phase objects and to find the cell property that has the dominant influence on this behavior. Starting with images obtained in the reconstruction step of the digital holographic microscopy technique, we developed a code for automated simultaneous individual cell image separation, identification, and counting, even when the cells are partially overlapped on a slide, and accurate measuring of their morphological features. To find the centroids of each cell, we propose a method based on analytical functions applied at threshold intervals. Our procedure separates the mature from the immature red blood cells and from the white blood cells through a decision based on gradient and radius values.

  20. QuantiFly: Robust Trainable Software for Automated Drosophila Egg Counting.

    PubMed

    Waithe, Dominic; Rennert, Peter; Brostow, Gabriel; Piper, Matthew D W

    2015-01-01

    We report the development and testing of software called QuantiFly: an automated tool to quantify Drosophila egg laying. Many laboratories count Drosophila eggs as a marker of fitness. The existing method requires laboratory researchers to count eggs manually while looking down a microscope. This technique is both time-consuming and tedious, especially when experiments require daily counts of hundreds of vials. The basis of the QuantiFly software is an algorithm which applies and improves upon an existing advanced pattern recognition and machine-learning routine. The accuracy of the baseline algorithm is additionally increased in this study through correction of bias observed in the algorithm output. The QuantiFly software, which includes the refined algorithm, has been designed to be immediately accessible to scientists through an intuitive and responsive user-friendly graphical interface. The software is also open-source, self-contained, has no dependencies and is easily installed (https://github.com/dwaithe/quantifly). Compared to manual egg counts made from digital images, QuantiFly achieved average accuracies of 94% and 85% for eggs laid on transparent (defined) and opaque (yeast-based) fly media. Thus, the software is capable of detecting experimental differences in most experimental situations. Significantly, the advanced feature recognition capabilities of the software proved to be robust to food surface artefacts like bubbles and crevices. The user experience involves image acquisition, algorithm training by labelling a subset of eggs in images of some of the vials, followed by a batch analysis mode in which new images are automatically assessed for egg numbers. Initial training typically requires approximately 10 minutes, while subsequent image evaluation by the software is performed in just a few seconds. Given the average time per vial for manual counting is approximately 40 seconds, our software introduces a timesaving advantage for experiments

  1. Comparison of cell counting methods in rodent pulmonary toxicity studies: automated and manual protocols and considerations for experimental design

    PubMed Central

    Zeidler-Erdely, Patti C.; Antonini, James M.; Meighan, Terence G.; Young, Shih-Houng; Eye, Tracy J.; Hammer, Mary Ann; Erdely, Aaron

    2016-01-01

    Pulmonary toxicity studies often use bronchoalveolar lavage (BAL) to investigate potential adverse lung responses to a particulate exposure. The BAL cellular fraction is counted, using automated (i.e. Coulter Counter®), flow cytometry or manual (i.e. hemocytometer) methods, to determine inflammatory cell influx. The goal of the study was to compare the different counting methods to determine which is optimal for examining BAL cell influx after exposure by inhalation or intratracheal instillation (ITI) to different particles with varying inherent pulmonary toxicities in both rat and mouse models. General findings indicate that total BAL cell counts using the automated and manual methods tended to agree after inhalation or ITI exposure to particle samples that are relatively nontoxic or at later time points after exposure to a pneumotoxic particle when the response resolves. However, when the initial lung inflammation and cytotoxicity was high after exposure to a pneumotoxic particle, significant differences were observed when comparing cell counts from the automated, flow cytometry and manual methods. When using total BAL cell count for differential calculations from the automated method, depending on the cell diameter size range cutoff, the data suggest that the number of lung polymorphonuclear leukocytes (PMN) varies. Importantly, the automated counts, regardless of the size cutoff, still indicated a greater number of total lung PMN when compared with the manual method, which agreed more closely with flow cytometry. The results suggest that either the manual method or flow cytometry would be better suited for BAL studies where cytotoxicity is an unknown variable. PMID:27251196

  2. Current automated 3D cell detection methods are not a suitable replacement for manual stereologic cell counting

    PubMed Central

    Schmitz, Christoph; Eastwood, Brian S.; Tappan, Susan J.; Glaser, Jack R.; Peterson, Daniel A.; Hof, Patrick R.

    2014-01-01

    Stereologic cell counting has had a major impact on the field of neuroscience. A major bottleneck in stereologic cell counting is that the user must manually decide whether or not each cell is counted according to three-dimensional (3D) stereologic counting rules by visual inspection within hundreds of microscopic fields-of-view per investigated brain or brain region. Reliance on visual inspection forces stereologic cell counting to be very labor-intensive and time-consuming, and is the main reason why biased, non-stereologic two-dimensional (2D) “cell counting” approaches have remained in widespread use. We present an evaluation of the performance of modern automated cell detection and segmentation algorithms as a potential alternative to the manual approach in stereologic cell counting. The image data used in this study were 3D microscopic images of thick brain tissue sections prepared with a variety of commonly used nuclear and cytoplasmic stains. The evaluation compared the numbers and locations of cells identified unambiguously and counted exhaustively by an expert observer with those found by three automated 3D cell detection algorithms: nuclei segmentation from the FARSIGHT toolkit, nuclei segmentation by 3D multiple level set methods, and the 3D object counter plug-in for ImageJ. Of these methods, FARSIGHT performed best, with true-positive detection rates between 38 and 99% and false-positive rates from 3.6 to 82%. The results demonstrate that the current automated methods suffer from lower detection rates and higher false-positive rates than are acceptable for obtaining valid estimates of cell numbers. Thus, at present, stereologic cell counting with manual decision for object inclusion according to unbiased stereologic counting rules remains the only adequate method for unbiased cell quantification in histologic tissue sections. PMID:24847213

  3. Phosphorylcholine-coated circuits improve preservation of platelet count and reduce expression of proinflammatory cytokines in CABG: a prospective randomized trial.

    PubMed

    Schulze, Costas J; Han, Lin; Ghorpade, Nitin; Etches, Wai S; Stang, Linda; Koshal, Arvind; Wang, Shao Hua

    2009-01-01

    The interaction of blood with foreign artificial surfaces during cardiopulmonary bypass (CPB) has been recognized as a major stimulus in evoking a systemic inflammatory and metabolic response. Phosphorylcholine (PC) is a new-generation coating material designed to ameliorate biocompatibility and thereby to reduce the detrimental interactions of CPB. We studied the effects of PC-coated perfusion circuits on platelet function and the humoral and cellular response to CPB. Thirty patients undergoing coronary artery bypass grafting were randomized to PC-coated (PC group, n = 15) and noncoated (control group, n = 15) circuit groups. Clinical data, total blood loss, and pre- and postoperative platelet counts were recorded and IL-6 and TNF-alpha, CD41a, CD42b, and CD62p were measured at induction of anesthesia, after the initiation of CPB and at termination of CPB. There was a significantly improved preservation of platelet count following CPB in the PC group (p = 0.028), which was sustained over a period of 72 hours. The use of PC-coated circuits further resulted in a significant attenuation of TNF-alpha and IL-6 expression (p < 0.05 and p < 0.01); however, we were unable to detect any differences in clinical outcomes. Despite similar clinical outcome, the obvious reduction of cytokine expression and improved preservation of platelet count suggest superior biocompatibility of PC-coated circuits.

  4. A High-Throughput Automated Technique for Counting Females of Heterodera glycines using a Fluorescence-Based Imaging System

    PubMed Central

    Brown, Sabrina; Yeckel, Gregory; Heinz, Robert; Clark, Kerry; Sleper, Dave; Mitchum, Melissa G.

    2010-01-01

    The soybean cyst nematode (SCN), Heterodera glycines, is the most damaging pathogen of soybean. Methods to phenotype soybean varieties for resistance to SCN are currently very laborious and time consuming. Streamlining a portion of this phenotyping process could increase productivity and accuracy. Here we report an automated method to count SCN females using a fluorescence-based imaging system that is well suited to high-throughput SCN phenotyping methods used in greenhouse screening. For optimal automated imaging, females were washed from roots at 30 days post-inoculation into small Petri dishes. Using a Kodak Image Station 4000MM Pro, the Petri dishes were scanned using excitation and emission wavelengths of 470 nm and 535 nm, respectively. Fluorescent images were captured and analyzed with Carestream Molecular Imaging Software for automated counting. We demonstrate that the automated fluorescent-based imaging system is just as accurate (r2 ≥ 0.95) and more efficient (>50% faster) than manual counting under a microscope. This method can greatly improve the consistency and turnaround of data while reducing the time and labor commitment associated with SCN female counting. PMID:22736857

  5. Derivation of New Readability Formulas (Automated Readability Index, Fog Count and Flesch Reading Ease Formula) for Navy Enlisted Personnel.

    ERIC Educational Resources Information Center

    Kincaid, J. P.; And Others

    Three readability formulas were recalculated to be more suitable for Navy use. The three formulas are the Automated Readability Index (ARI), Fog Count, and Flesch Reading Ease Formula. They were derived from test results of 531 Navy enlisted personnel enrolled in four technical training schools. Personnel were tested for their reading…

  6. Vascular endothelial growth factor corrected for platelet count and hematocrit is associated with the clinical course of aplastic anemia in children.

    PubMed

    Kodama, Yuichi; Okamoto, Yasuhiro; Hashiguchi, Teruto; Shinkoda, Yuichi; Nishikawa, Takuro; Tanabe, Takayuki; Kawano, Yoshifumi

    2012-05-01

    The wide variety of clinical courses that lead to the development of severe aplastic anemia (AA) makes it difficult to speculate whether treatment for AA is required in the early phase. The objective of this study was to identify a method for predicting the clinical course of AA at the onset of the disease. First, in healthy adults, vascular endothelial growth factor (VEGF) released per platelet was measured by the activation of platelet-rich plasma (PRP) and platelet-poor plasma (PPP). Serum concentration of VEGF, serum concentration of VEGF corrected for platelet count, and serum concentration of VEGF corrected for both platelet count and hematocrit (corrected VEGF) were then compared to VEGF released per platelet. Corrected VEGF showed the best correlation with VEGF released per platelet by the activation of PRP in healthy subjects (R (2) = in a single 0.806, p = 0.001). Next, corrected VEGF was assayed in 11 pediatric patients with AA at the time of diagnosis. Corrected VEGF in AA patients was significantly greater than that in age-matched control subjects [1.32 × 10(-6) pg (range 0.36-1.85) vs. 0.18 × 10(-6) pg (range 0.12-0.94)] (p = 0.002). Moreover, corrected VEGF in AA patients who did not require treatment for more than 2 years was significantly greater than that in AA patients who required earlier treatment [1.67 × 10(-6) pg (range 1.32-1.85) vs. 0.87 × 10(-6) pg (0.36-1.34)] (p = 0.011). These data indicate that a compensatory mechanism for increasing VEGF and preventing disease progression might play a role in AA. Corrected VEGF may be useful for predicting the clinical course of AA.

  7. High-Throughput Method for Automated Colony and Cell Counting by Digital Image Analysis Based on Edge Detection.

    PubMed

    Choudhry, Priya

    2016-01-01

    Counting cells and colonies is an integral part of high-throughput screens and quantitative cellular assays. Due to its subjective and time-intensive nature, manual counting has hindered the adoption of cellular assays such as tumor spheroid formation in high-throughput screens. The objective of this study was to develop an automated method for quick and reliable counting of cells and colonies from digital images. For this purpose, I developed an ImageJ macro Cell Colony Edge and a CellProfiler Pipeline Cell Colony Counting, and compared them to other open-source digital methods and manual counts. The ImageJ macro Cell Colony Edge is valuable in counting cells and colonies, and measuring their area, volume, morphology, and intensity. In this study, I demonstrate that Cell Colony Edge is superior to other open-source methods, in speed, accuracy and applicability to diverse cellular assays. It can fulfill the need to automate colony/cell counting in high-throughput screens, colony forming assays, and cellular assays.

  8. High-Throughput Method for Automated Colony and Cell Counting by Digital Image Analysis Based on Edge Detection

    PubMed Central

    Choudhry, Priya

    2016-01-01

    Counting cells and colonies is an integral part of high-throughput screens and quantitative cellular assays. Due to its subjective and time-intensive nature, manual counting has hindered the adoption of cellular assays such as tumor spheroid formation in high-throughput screens. The objective of this study was to develop an automated method for quick and reliable counting of cells and colonies from digital images. For this purpose, I developed an ImageJ macro Cell Colony Edge and a CellProfiler Pipeline Cell Colony Counting, and compared them to other open-source digital methods and manual counts. The ImageJ macro Cell Colony Edge is valuable in counting cells and colonies, and measuring their area, volume, morphology, and intensity. In this study, I demonstrate that Cell Colony Edge is superior to other open-source methods, in speed, accuracy and applicability to diverse cellular assays. It can fulfill the need to automate colony/cell counting in high-throughput screens, colony forming assays, and cellular assays. PMID:26848849

  9. Washing of platelets can be fully automated using a closed-system cell processor and BRS-A platelet additive solution.

    PubMed

    Oikawa, S; Minegishi, M; Endo, K; Kawashima, W; Suzuki, K; Shimizu, H

    2016-11-01

    This study evaluated the in vitro properties of platelets (PLTs) washed with BRS-A additive solution in the Haemonetics ACP215 automated processing system. Two washing modes, 'manually/automatically adding ACD-A to BRS before/during the washing process', represented the control and test groups, respectively. Outcomes were compared over 7 days of storage (n = 7, for both). PLT recovery following washing processing (26-27 min) was 86·2 ± 1·7% and 86·0 ± 2·2% and plasma protein removal was 98·8 ± 0·3% and 99·0 ± 0·2% in the control and test groups, respectively (not significant). Both groups exhibited comparable in vitro properties.

  10. Comparison of white and red blood cell estimates in urine sediment with hemocytometer and automated counts in dogs and cats.

    PubMed

    O'Neil, Elizabeth; Burton, Shelley; Horney, Barbara; MacKenzie, Allan

    2013-03-01

    Therapeutic decisions regarding urinalysis are commonly based on the presence of white and red blood cells. Traditionally, numbers per high-power field are estimated using wet-mount microscopic examination. This technique is not standardized and counts are likely prone to inaccuracy. In addition, differentiation of leukocyte types is not possible. The aims of this study were to (1) compare WBC and RBC estimates using wet-mount examination with counts obtained using a hemocytometer, (2) assess if a hematology automated analyzer (Sysmex ST-2000iV/XT) provides reliable WBC and RBC counts in urine comparable to hemocytometer counts, and (3) evaluate air-dried Wright-Giemsa-stained urine drop sediment preparations for the determination of differential leukocyte counts. WBC and RBC counts were obtained by performing wet-mount estimates, manual hemocytometer counts, and Sysmex automated counts on 219 canine and feline urine samples. Results were correlated using Spearman rank correlation. Air-dried Wright-Giemsa stained sediment drop preparations (n = 215) were examined for differential counts of leukocytes. A low but significant association was found between WBC estimates on wet-mount examination and hemocytometer counts (rho = 0.37, P < .01). There was a high and significant association when RBC counts were compared between wet-mount and hemocytometer evaluation (rho = 0.7, P < .01). There was very high and significant interassay correlation between Sysmex data from duplicate samples for what the analyzer classified as WBC (rho = 0.97, P < .01) and RBC (rho = 0.94, P < .01). Low correlations were found between the Sysmex RBC counts and both wet-mount estimates and hemocytometer RBC counts (rho = 0.43, P < .01 and rho = 0.39, P < .01, respectively). Cell preservation in the air-dried sediment preparations was so poor that differential counts could not be performed. WBC and RBC estimates on wet-mount examination agreed with hemocytometer counts and are therefore

  11. A new scoring system derived from base excess and platelet count at presentation predicts mortality in paediatric meningococcal sepsis.

    PubMed

    Couto-Alves, Alexessander; Wright, Victoria J; Perumal, Karnan; Binder, Alexander; Carrol, Enitan D; Emonts, Marieke; de Groot, Ronald; Hazelzet, Jan; Kuijpers, Taco; Nadel, Simon; Zenz, Werner; Ramnarayan, Padmanabhan; Levin, Michael; Coin, Lachlan; Inwald, David P

    2013-04-11

    The aim of this study was to derive a novel prognostic score for mortality in paediatric meningococcal sepsis (MS) based on readily available laboratory markers. A multicentre retrospective cohort study for the consortium set and a single centre retrospective study for replication set. The consortium set were 1,073 children (age 1 week to 17.9 years) referred over a 15-year period (1996 to 2011), who had an admission diagnosis of MS, referred to paediatric intensive care units (PICUs) in six different European centres. The consortium set was split into a development set and validation set to derive the score. The replication set were 134 children with MS (age 2 weeks to 16 years) referred over a 4-year period (2007 to 2011) to PICUs via the Children's Acute Transport Service (CATS), London. A total of 85/1,073 (7.9%) children in the consortium set died. A total of 16/134 (11.9%) children in the replication set died. Children dying in the consortium set had significantly lower base excess, C-reactive protein (CRP), platelet and white cell count, more deranged coagulation and higher lactate than survivors. Paediatric risk of mortality (PRISM) score, Glasgow meningococcal septicaemia prognosis score (GMSPS) and Rotterdam score were also higher. Using the consortium set, a new scoring system using base excess and platelet count at presentation, termed the BEP score, was mathematically developed and validated. BEP predicted mortality with high sensitivity and specificity scores (area under the curve (AUC) in the validation set=0.86 and in the replication set=0.96). In the validation set, BEP score performance (AUC=0.86, confidence interval (CI): 0.80 to 0.91) was better than GMSPS (AUC=0.77, CI: 0.68, 0.85), similar to Rotterdam (AUC=0.87, CI: 0.81 to 0.93) and not as good as PRISM (AUC=0.93, CI: 0.85 to 0.97). The BEP score, relying on only two variables that are quickly and objectively measurable and readily available at presentation, is highly sensitive and specific

  12. Relationship between automated total nucleated cell count and enumeration of cells on direct smears of canine synovial fluid

    PubMed Central

    Dusick, Allison; Young, Karen M.; Muir, Peter

    2016-01-01

    Canine osteoarthritis is a common condition seen in veterinary clinical practice and causes considerable morbidity in dogs as they age. Synovial fluid analysis is an important tool for diagnosis and treatment of canine joint disease and obtaining a total nucleated cell count (TNCC) is particularly important. The low volume of fluid obtained during arthrocentesis is often insufficient for obtaining an automated TNCC, thereby limiting sample interpretation. The aim of the present study was to investigate whether estimation of TNCC in canine synovial fluid could be achieved by performing manual cell counts on direct smears of fluid. Fifty eight synovial fluid samples, taken by arthrocentesis from 48 dogs, were included in the study. Direct smears of synovial fluid were prepared, and hyaluronidase added before cell counts were obtained using a commercial laser-based instrument. A protocol was established to count nucleated cells in a specific region of the smear, using a serpentine counting pattern; mean number of nucleated cells/400× field was then calculated. There was a positive correlation between the automated TNCC and mean manual cell count, with more variability at higher TNCC. Regression analysis was performed to estimate TNCC from manual counts. By this method, 78% of the samples were correctly predicted to fall into one of three categories (within the reference interval, mildly to moderately elevated, or markedly elevated) relative to the automated TNCC. Intra-observer and inter-observer agreement was good to excellent. The results of the study suggest that interpretation of canine synovial fluid samples of low volume can be aided by manual cell counting of direct smears. PMID:25439439

  13. [Automated hematology analysers and spurious counts Part 3. Haemoglobin, red blood cells, cell count and indices, reticulocytes].

    PubMed

    Godon, Alban; Genevieve, Franck; Marteau-Tessier, Anne; Zandecki, Marc

    2012-01-01

    Several situations lead to abnormal haemoglobin measurement or to abnormal red blood cells (RBC) counts, including hyperlipemias, agglutinins and cryoglobulins, haemolysis, or elevated white blood cells (WBC) counts. Mean (red) cell volume may be also subject to spurious determination, because of agglutinins (mainly cold), high blood glucose level, natremia, anticoagulants in excess and at times technological considerations. Abnormality related to one measured parameter eventually leads to abnormal calculated RBC indices: mean cell haemoglobin content is certainly the most important RBC parameter to consider, maybe as important as flags generated by the haematology analysers (HA) themselves. In many circumstances, several of the measured parameters from cell blood counts (CBC) may be altered, and the discovery of a spurious change on one parameter frequently means that the validity of other parameters should be considered. Sensitive flags allow now the identification of several spurious counts, but only the most sophisticated HA have optimal flagging, and simpler ones, especially those without any WBC differential scattergram, do not share the same capacity to detect abnormal results. Reticulocytes are integrated into the CBC in many HA, and several situations may lead to abnormal counts, including abnormal gating, interference with intraerythrocytic particles, erythroblastosis or high WBC counts.

  14. Effect of an automated dipping and backflushing system on somatic cell counts.

    PubMed

    Olde Riekerink, R G M; Ohnstad, I; van Santen, B; Barkema, H W

    2012-09-01

    Postmilking teat disinfection is an effective management practice to prevent transmission of contagious mastitis pathogens from cow to cow. With farms increasing in size and an increase in the number of rotary milking parlors, the need for automation of postmilking teat disinfection is mounting. Automated teat dipping and backflushing (ADB) systems have existed for some years, but their effect on udder health was never examined in a field study on commercial dairy farms. The objectives of this study were, therefore, to evaluate the effect of introducing an ADB system in a herd on (1) bulk milk somatic cell count (SCC), (2) individual cow SCC, and (3) the proportion of newly elevated SCC. Dairy herd improvement data were collected over a 30-mo period on 25 sets of 3 farms. Each set of 3 farms contained a farm that installed an ADB system, one that disinfected teats using dipping after milking, and one that sprayed teats after milking. Data were analyzed using linear mixed models. Bulk milk SCC on farms that sprayed or dipped before installing an ADB system were 16,000 and 30,000 cells/mL lower in the period 6 to 18 mo after installation, respectively, than on farms that continued spraying or dipping the teats after milking. In the same period after installing an ADB system, proportions of cows with elevated SCC were 4.3 and 1.2% lower, respectively, compared with spraying and with dipping. Similarly, proportions of cows that had newly elevated SCC were 1.5% lower and 0.3% higher, respectively, compared with farms that sprayed or dipped. Installing an ADB system had a beneficial effect on bulk milk SCC, individual cow SCC, and the proportion of newly elevated SCC. The effect was most prominent in the period 6 to 18 mo after installation of an ADB system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Differentiation of acute fatty liver of pregnancy from syndrome of hemolysis, elevated liver enzymes and low platelet counts.

    PubMed

    Minakami, Hisanori; Morikawa, Mamoru; Yamada, Takahiro; Yamada, Takashi; Akaishi, Rina; Nishida, Ryutaro

    2014-03-01

    As proposed criteria (Swansea criteria) for the diagnosis of acute fatty liver of pregnancy (AFLP) do not include antithrombin (AT) activity, diagnosis of AFLP may be delayed. The aim of this review is to underscore problems in the differential diagnosis of AFLP and the syndrome of hemolysis, elevated liver enzymes and low platelet counts (HELLP syndrome) and to facilitate prompt diagnosis of AFLP. Published works dealing with liver dysfunction in pregnancy, HELLP syndrome and AFLP were reviewed. AFLP and HELLP syndrome shared common clinical, laboratory, histological and genetic features, and differential diagnosis between them was often difficult. However, HELLP syndrome was likely to occur in patients with hypertension, but AFLP occurred often in the absence of hypertension. In addition, AFLP was exclusively associated with pregnancy-induced antithrombin deficiency (PIATD). Approximately 50% of patients with AFLP did not have thrombocytopenia at presentation. As the Swansea criteria for AFLP did not include PIATD, diagnosis of AFLP was delayed until manifestation of life-threatening complications; 60% of women were admitted to intensive care and 15% to a specialist liver unit. In conclusion, incorporation of AT activity of less than 65% into the diagnostic criteria for AFLP may facilitate suspicion and prompt diagnosis of AFLP, decrease uncertainty regarding the diagnosis of AFLP, and contribute to better investigation and understanding of the process leading to the development of liver dysfunction.

  16. Trypanosoma cruzi infectivity assessment in "in vitro" culture systems by automated cell counting.

    PubMed

    Liempi, Ana; Castillo, Christian; Cerda, Mauricio; Droguett, Daniel; Duaso, Juan; Barahona, Katherine; Hernández, Ariane; Díaz-Luján, Cintia; Fretes, Ricardo; Härtel, Steffen; Kemmerling, Ulrike

    2015-03-01

    Chagas disease is an endemic, neglected tropical disease in Latin America that is caused by the protozoan parasite Trypanosoma cruzi. In vitro models constitute the first experimental approach to study the physiopathology of the disease and to assay potential new trypanocidal agents. Here, we report and describe clearly the use of commercial software (MATLAB(®)) to quantify T. cruzi amastigotes and infected mammalian cells (BeWo) and compared this analysis with the manual one. There was no statistically significant difference between the manual and the automatic quantification of the parasite; the two methods showed a correlation analysis r(2) value of 0.9159. The most significant advantage of the automatic quantification was the efficiency of the analysis. The drawback of this automated cell counting method was that some parasites were assigned to the wrong BeWo cell, however this data did not exceed 5% when adequate experimental conditions were chosen. We conclude that this quantification method constitutes an excellent tool for evaluating the parasite load in cells and therefore constitutes an easy and reliable ways to study parasite infectivity. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Automated Axon Counting in Rodent Optic Nerve Sections with AxonJ

    NASA Astrophysics Data System (ADS)

    Zarei, Kasra; Scheetz, Todd E.; Christopher, Mark; Miller, Kathy; Hedberg-Buenz, Adam; Tandon, Anamika; Anderson, Michael G.; Fingert, John H.; Abràmoff, Michael David

    2016-05-01

    We have developed a publicly available tool, AxonJ, which quantifies the axons in optic nerve sections of rodents stained with paraphenylenediamine (PPD). In this study, we compare AxonJ’s performance to human experts on 100x and 40x images of optic nerve sections obtained from multiple strains of mice, including mice with defects relevant to glaucoma. AxonJ produced reliable axon counts with high sensitivity of 0.959 and high precision of 0.907, high repeatability of 0.95 when compared to a gold-standard of manual assessments and high correlation of 0.882 to the glaucoma damage staging of a previously published dataset. AxonJ allows analyses that are quantitative, consistent, fully-automated, parameter-free, and rapid on whole optic nerve sections at 40x. As a freely available ImageJ plugin that requires no highly specialized equipment to utilize, AxonJ represents a powerful new community resource augmenting studies of the optic nerve using mice.

  18. Automated Axon Counting in Rodent Optic Nerve Sections with AxonJ

    PubMed Central

    Zarei, Kasra; Scheetz, Todd E.; Christopher, Mark; Miller, Kathy; Hedberg-Buenz, Adam; Tandon, Anamika; Anderson, Michael G.; Fingert, John H.; Abràmoff, Michael David

    2016-01-01

    We have developed a publicly available tool, AxonJ, which quantifies the axons in optic nerve sections of rodents stained with paraphenylenediamine (PPD). In this study, we compare AxonJ’s performance to human experts on 100x and 40x images of optic nerve sections obtained from multiple strains of mice, including mice with defects relevant to glaucoma. AxonJ produced reliable axon counts with high sensitivity of 0.959 and high precision of 0.907, high repeatability of 0.95 when compared to a gold-standard of manual assessments and high correlation of 0.882 to the glaucoma damage staging of a previously published dataset. AxonJ allows analyses that are quantitative, consistent, fully-automated, parameter-free, and rapid on whole optic nerve sections at 40x. As a freely available ImageJ plugin that requires no highly specialized equipment to utilize, AxonJ represents a powerful new community resource augmenting studies of the optic nerve using mice. PMID:27226405

  19. Effects of polyethylene glycol-conjugated recombinant human megakaryocyte growth and development factor on platelet counts after chemotherapy for lung cancer.

    PubMed

    Fanucchi, M; Glaspy, J; Crawford, J; Garst, J; Figlin, R; Sheridan, W; Menchaca, D; Tomita, D; Ozer, H; Harker, L

    1997-02-06

    Polyethylene glycol (PEG)-conjugated recombinant human megakaryocyte growth and development factor (MGDF, also known as PEG-rHuMGDF), a recombinant molecule related to thrombopoietin, specifically stimulates megakaryopoiesis and platelet production and reduces the severity of thrombocytopenia in animals receiving myelosuppressive chemotherapy. We conducted a randomized, double-blind, placebo-controlled dose-escalation study of MGDF in 53 patients with lung cancer who were treated with carboplatin and paclitaxel. The patients were randomly assigned in blocks of 4 in a 1:3 ratio to receive either placebo or MGDF (0.03, 0.1, 0.3, 1.0, 3.0, or 5.0 microg per kilogram of body weight per day), injected subcutaneously. No other marrow-active cytokines were given. In the 38 patients who received MGDF after chemotherapy, the median nadir platelet count was 188,000 per cubic millimeter (range, 68,000 to 373,000), as compared with 111,000 per cubic millimeter (range, 21,000 to 307,000) in 12 patients receiving placebo (P = 0.013). The platelet count recovered to base-line levels in 14 days in the treated patients as compared with more than 21 days in those receiving placebo (P<0.001). Among all 40 patients treated with MGDF, 1 had deep venous thrombosis and pulmonary embolism, and another had superficial thrombophlebitis. MGDF has potent stimulatory effects on platelet production in patients with chemotherapy-induced thrombocytopenia.

  20. Acute onset of severe hemolysis, elevated liver enzymes, and low platelet count syndrome in a patient with a partial hydatidiform mole at 17 weeks gestation.

    PubMed

    Sherer, David M; Dalloul, Mudar; Stimphil, Raphael; Hellmann, Mira; Khoury-Collado, Fady; Osho, Joseph; Fomitcheva, Larissa; Brennan, Kelly J; Abulafia, Ovadia

    2006-04-01

    Preeclampsia is uncommon prior to 24 weeks gestation and has been associated with partial and complete hydatidiform moles. We present an unusual case in which a patient was diagnosed with preeclampsia at 17 weeks gestation. Ultrasound findings were consistent with a partial hydatidiform mole. Within 24 hours of the onset of symptoms, the patient developed severe hemolysis, elevated liver enzymes, and low platelet count syndrome, with a platelet count of 20 x 10 (9) cells/L. Termination of pregnancy was performed with rapid resolution of signs, symptoms, and laboratory abnormalities. Triploid 69,XXY was confirmed at karyotype analysis. This case demonstrates the acuteness in which life-threatening maternal conditions can arise with this uncommon complication of pregnancy, and the importance of correct identification of the characteristic ultrasonographic findings associated with a partial hydatidiform mole.

  1. Semi-automated counting of axon regeneration in poly(lactide co-glycolide) spinal cord bridges.

    PubMed

    McCreedy, Dylan A; Margul, Daniel J; Seidlits, Stephanie K; Antane, Jennifer T; Thomas, Ryan J; Sissman, Gillian M; Boehler, Ryan M; Smith, Dominique R; Goldsmith, Sam W; Kukushliev, Todor V; Lamano, Jonathan B; Vedia, Bansi H; He, Ting; Shea, Lonnie D

    2016-04-01

    Spinal cord injury (SCI) is a debilitating event with multiple mechanisms of degeneration leading to life-long paralysis. Biomaterial strategies, including bridges that span the injury and provide a pathway to reconnect severed regions of the spinal cord, can promote partial restoration of motor function following SCI. Axon growth through the bridge is essential to characterizing regeneration, as recovery can occur via other mechanisms such as plasticity. Quantitative analysis of axons by manual counting of histological sections can be slow, which can limit the number of bridge designs evaluated. In this study, we report a semi-automated process to resolve axon numbers in histological sections, which allows for efficient analysis of large data sets. Axon numbers were estimated in SCI cross-sections from animals implanted with poly(lactide co-glycolide) (PLG) bridges with multiple channels for guiding axons. Immunofluorescence images of histological sections were filtered using a Hessian-based approach prior to threshold detection to improve the signal-to-noise ratio and filter out background staining associated with PLG polymer. Semi-automated counting successfully recapitulated average axon densities and myelination in a blinded PLG bridge implantation study. Axon counts obtained with the semi-automated technique correlated well with manual axon counts from blinded independent observers across sections with a wide range of total axons. This semi-automated detection of Hessian-filtered axons provides an accurate and significantly faster alternative to manual counting of axons for quantitative analysis of regeneration following SCI. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Blood fluidity and outcome after femoropopliteal percutaneous transluminal angioplasty (PTA): role of plasma viscosity and low platelet count in predicting restenosis.

    PubMed

    van der Loo, Bernd; Kovacevic, Tamara; Krieger, Elisabeth; Banyai, Susanne; Banyai, Martin; Amann-Vesti, Beatrice R; Jagacic, Dorijan; Rousson, Valentin; Koppensteiner, Renate

    2005-01-01

    Rheological abnormalities are well known in patients with peripheral arterial occlusive disease (PAOD). We wanted to determine whether rheological variables are related to restenosis after femoropopliteal percutaneous transluminal angioplasty (PTA). In 114 patients (62 men; median age 70 years) undergoing femoropopliteal PTA for symptomatic peripheral arterial occlusive disease (PAOD) plasma viscosity, red cell aggregation, whole blood viscosity, hematocrit, fibrinogen, platelet count, leukocytes and C-reactive protein were determined the day after the procedure and at 1, 3, and 12 months. The primary endpoint was restenosis >50% documented by duplexsonography up to 12 months. Cox proportional hazards analysis was used to assess the risk of restenosis for postinterventional values of rheological variables. Forty-eight patients (42%) developed restenosis at 12 months. Patients with restenosis had higher baseline plasma viscosity (PV) (medians, 1.71 vs. 1.65 millipascal seconds [mPa.s]; p = 0.04) and lower platelet count (224 vs. 240 x 10(3)/microl; p = 0.03) than patients without restenosis. The hazard ratio (HR; 95% CI) of incident restenosis was 9.2 (1.12-76; p = 0.03) for PV and 0.99 (0.99-1.0; p = 0.07) for PLT. When examining jointly both high PV and low platelet count (PLT), patients with PV > 1.66 mPa.s and PLT < 233 x 10(3)/microl (i.e. variables split at their respective median) had an increased risk of restenosis (log-rank test p = 0.01). Multivariate Cox proportional hazard analysis showed that plasma viscosity (p = 0.02), low platelet count (p = 0.01), lesion length (p = 0.0037) and lack of hypertension (p = 0.01) were associated with restenosis at 12 months. No associations were found between restenosis and the other rheological and inflammatory variables studied. Our data suggest that increased PV and low PLT contribute to restenosis after femoropopliteal PTA.

  3. Evaluation of the Value of d-Dimer, P-Selectin, and Platelet Count for Prediction of Portal Vein Thrombosis After Devascularization.

    PubMed

    Fei, Yang; Zong, Guang-Quan; Chen, Jian; Liu, Ren-Min

    2016-07-01

    To evaluate the value of d-dimer, P-selectin, and platelet count in patients with cirrhotic portal hypertension (PHT) for prediction of portal vein thrombosis (PVT) after devascularization. A total of 137 patients with cirrhotic PHT who undergone devascularization from January 2012 to April 2014 were retrospectively reviewed, all of them were divided into 2 groups (PVT group and non-PVT group) by Doppler ultrasonography (DU) examination. The level of d-dimer, P-selectin, and platelet count was tested during the perioperative period. In all, 38 (27.7%) patients were found to have PVT by DU examination postoperatively. In contrast to the non-PVT group, the level of d-dimer, P-selectin, and platelet count in the PVT group was much higher significantly at 1, 3, and 7 days after devascularization. (P < .05). However, in the 15 days after surgery, the difference in P-selectin between the 2 groups was not significant (P = .260). It was shown that the highest sensitivity of the 3 markers for PVT was d-dimer, the highest specificity belonged to P-selectin. The area under receiver-operating characteristic (ROC) curve of P-selectin was the biggest of the 3 markers. When the 3 markers were combined to be used to diagnose PVT, the sensitivity was increased to 0.907, with a slight drop of specificity to 0.693, the area under the ROC curve was 0.927. The level of d-dimer, P-selectin, and platelet count might be good candidate predictive markers for PVT in patients with cirrhotic PHT after devascularization. The combined test of the 3 markers can increase the value of prediction. © The Author(s) 2015.

  4. The expression and concentration of CD40 ligand in normal pregnancy, preeclampsia, and hemolytic anemia, elevated liver enzymes and low platelet count (HELLP) syndrome.

    PubMed

    Azzam, Hanan A G; Abousamra, Nashwa K; Goda, Hossam; El-Shouky, Reda; El-Gilany, Abdel-Hady

    2013-01-01

    Preeclampsia has been associated with increased platelet activation detected before disease onset. Inappropriate activation of platelets may be involved in pathogenesis in preeclampsia by promoting coagulation and thrombosis and also as a mediator of inflammation. The exaggerated platelet activation and inflammation leading to endothelial damage in preeclampsia can be explained by the CD40-CD40 ligand (CD40L) system. Expression of CD40L on platelets was determined by whole-blood flow cytometry, and serum levels of soluble CD40L (sCD40L) were measured by enzyme-linked immunosorbent assay in 11 women with mild preeclampsia, 11 women with severe preeclampsia, and six women with hemolytic anemia, elevated liver enzymes and low platelet count (HELLP) syndrome compared with 13 normotensive pregnant women as a control group. The platelet surface expression of CD40L was significantly higher in women with mild and severe preeclampsia and HELLP compared with normal pregnancy group (P = 0.001; P ≤ 0.001; P = 0.003, respectively), with no significant difference being found between women with mild preeclampsia compared with HELLP and severe preeclampsia compared with HELLP (P = 0.2; P = 0.8, respectively). The serum concentration of sCD40L was significantly higher in women with mild and severe preeclampsia and HELLP compared with the normal pregnancy group (P = 0.001; P ≤ 0.001; P = 0.022, respectively), with no significant difference being found between women with mild compared with severe preeclampsia or HELLP and severe preeclampsia compared with HELLP (P = 0.7; P = 0.6; P = 0.6, respectively). In conclusion, the higher expression and concentration of CD40L in women with preeclampsia and HELLP syndrome compared with normal pregnant women may indicate an exaggerated activation of platelets and endothelial cells in the disorder.

  5. Agreement of manual cell counts and automated counts of the scil Vet abc Plus(+) hematology analyzer for analysis of equine synovial fluid.

    PubMed

    Van de Water, Eline; Oosterlinck, Maarten; Duchateau, Luc; Pille, Frederik

    2016-06-01

    The purpose of this study was to determine whether the scil Vet abc Plus(+) (SCIL Animal Care Company, Altorf, France), an impedance hematology analyzer, can accurately quantify and differentiate nucleated blood cells (NBCs) in equine synovial fluid. Synovial fluid samples (n=242) in different stages of experimentally induced inflammation were analyzed with and without hyaluronidase pretreatment and compared to manual hemocytometer counts and smear reviews. No significant effect of hyaluronidase pretreatment was observed. Total nucleated cell counts of the scil Vet abc Plus(+) were significantly higher compared to the manual method (P=0.02), yet the difference was small and clinically irrelevant (ratio manual/automated count equal to 0.97 with 95% CI [0.95, 1.00]). Differential cell counts of the scil Vet abc Plus(+) were not accurate. In conclusion, the scil Vet abc Plus(+) hematology analyzer is highly accurate for quantification, but not accurate for differentiation of NBCs in equine synovial fluid. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. COVASIAM: an Image Analysis Method That Allows Detection of Confluent Microbial Colonies and Colonies of Various Sizes for Automated Counting

    PubMed Central

    Corkidi, G.; Diaz-Uribe, R.; Folch-Mallol, J. L.; Nieto-Sotelo, J.

    1998-01-01

    In this work we introduce the confluent and various sizes image analysis method (COVASIAM), an automated colony count technique that uses digital imaging technology for detection and separation of confluent microbial colonies and colonies of various sizes growing on petri dishes. The proposed method takes advantage of the optical properties of the surfaces of most microbial colonies. Colonies in the petri dish are epi-illuminated in order to direct the reflection of concentrated light coming from a halogen lamp towards an image-sensing device. In conjunction, a multilevel threshold algorithm is proposed for colony separation and counting. These procedures improved the quantification of colonies showing confluence or differences in size. We tested COVASIAM with a sample set of microorganisms that form colonies with contrasting physical properties: Saccharomyces cerevisiae, Aspergillus nidulans, Escherichia coli, Azotobacter vinelandii, Pseudomonas aeruginosa, and Rhizobium etli. These physical properties range from smooth to hairy, from bright to opaque, and from high to low convexities. COVASIAM estimated an average of 95.47% (ς = 8.55%) of the manually counted colonies, while an automated method based on a single-threshold segmentation procedure estimated an average of 76% (ς = 16.27) of the manually counted colonies. This method can be easily transposed to almost every image-processing analyzer since the procedures to compile it are generically standard. PMID:9546177

  7. Granulocyte colony-stimulating factor increases the platelet volume in peripheral stem cell apheresis donors.

    PubMed

    Ihara, Akihiro; Matsui, Keiko; Minami, Ryouta; Uchida, Shuzou; Ueda, Shuji; Nishiura, Tetsuo

    2008-01-01

    We investigated the short-term influence of granulocyte colony-stimulating factor (G-CSF) administration on platelet counts and platelet indices in 12 donors (8 males and 4 females; median age 34 years, range 16-49) for peripheral stem cell transplantation using an automated blood cell analyzer. On day 3 (D3) compared with D0, 11 donors with normal laboratory and physical findings showed increases in platelet indices (chi(2) = 12.0, p = 0.0025). Furthermore, mean platelet volume (MPV) was significantly increased (p = 0.04). Also, platelet count decreased, and platelet distribution width and platelet-large cell ratio were increased, but these were not significant. On the contrary, 1 donor with abnormal laboratory findings who had large platelets (MPV 11.4 fl) before G-CSF administration showed decreases in platelet indices (MPV 10.3 fl) on D3, although platelet count (18.2 x 10(4)/microl) decreased after G-CSF administration. G-CSF administration induces an inflammatory process with endothelial cell activation. This is probably the reason why platelet volume increases after G-CSF use. This is the first report showing that G-CSF administration immediately induces increases in large platelets in peripheral stem cell transplant donors before harvest.

  8. Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation

    PubMed Central

    Estcourt, Lise J; Stanworth, Simon J; Doree, Carolyn; Hopewell, Sally; Trivella, Marialena; Murphy, Michael F

    2015-01-01

    Background Platelet transfusions are used in modern clinical practice to prevent and treat bleeding in people who are thrombocytopenic due to bone marrow failure. Although considerable advances have been made in platelet transfusion therapy in the last 40 years, some areas continue to provoke debate, especially concerning the use of prophylactic platelet transfusions for the prevention of thrombocytopenic bleeding. This is an update of a Cochrane review first published in 2004, and previously updated in 2012 that addressed four separate questions: prophylactic versus therapeutic-only platelet transfusion policy; prophylactic platelet transfusion threshold; prophylactic platelet transfusion dose; and platelet transfusions compared to alternative treatments. This review has now been split into four smaller reviews looking at these questions individually; this review compares prophylactic platelet transfusion thresholds. Objectives To determine whether different platelet transfusion thresholds for administration of prophylactic platelet transfusions (platelet transfusions given to prevent bleeding) affect the efficacy and safety of prophylactic platelet transfusions in preventing bleeding in people with haematological disorders undergoing myelosuppressive chemotherapy or haematopoietic stem cell transplantation (HSCT). Search methods We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library 2015, Issue 6, 23 July 2015), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), the Transfusion Evidence Library (from 1950), and ongoing trial databases to 23 July 2015. Selection criteria We included RCTs involving transfusions of platelet concentrates, prepared either from individual units of whole blood or by apheresis, and given to prevent bleeding in people with haematological disorders (receiving myelosuppressive chemotherapy or undergoing HSCT) that compared different thresholds for

  9. Platelet count response to H. pylori treatment in patients with immune thrombocytopenic purpura with and without H. pylori infection: a systematic review

    PubMed Central

    Arnold, Donald M.; Bernotas, Ashley; Nazi, Ishac; Stasi, Roberto; Kuwana, Masataka; Liu, Yang; Kelton, John G.; Crowther, Mark A.

    2009-01-01

    Eradication of H. pylori improves thrombocytopenia in some patients with immune thrombocytopenic purpura by mechanisms that remain obscure. Platelet count responses may occur independently of H. pylori infection as a result of the immune modulating effects of macrolide antimicrobials or the removal of other commensal bacteria. We performed a systematic review of the literature to determine the effect of H. pylori eradication therapy in patients with immune thrombocytopenic purpura by comparing the platelet response in patients who were, and who were not infected with H. pylori. MEDLINE, EMBASE, Cochrane central registry and abstracts from the American Society of Hematology (from 2003) were searched in duplicate and independently without language or age restrictions. Eleven studies, 8 from Japan, were included enrolling 282 patients with immune thrombocytopenic purpura who received eradication therapy; 205 were H. pylori-positive and 77 were H. pylori-negative. The odds of achieving a platelet count response following eradication therapy were 14.5 higher (95% confidence interval 4.2 to 83.0) in patients with H. pylori infection (51.2% vs. 8.8%). No study reported bleeding or quality of life. Adverse events were reported in 12 patients. H. pylori eradication therapy was of little benefit for H. pylori-negative patients. These findings strengthen the causal association between H. pylori infection and immune thrombocytopenia in some patients. Randomized trials are needed to determine the applicability of H. pylori eradication therapy across diverse geographical regions. PMID:19483158

  10. Feasibility of implementing an automated culture system for bacteria screening in platelets in the blood bank routine.

    PubMed

    Castro, E; Bueno, J L; Barea, L; González, R

    2005-06-01

    Bacterial contamination of blood components is the principal infectious complication linked to transfusion. The aim of the study was to evaluate the applicability of an automated culture system for platelets. 10 141 platelet concentrates were cultured individually and in pools of five on storage days 1 and 7 using Bact/Alert system aerobic bottles. A modified collection bag was used for improved sampling. Five-millilitre samples were cultured at 37 degrees C for 7 days. Only those samples where the same bacteria were identified in reculture were considered true positives (TP). Homogeneity of proportions was tested by Fisher's exact test. The rate of TP was 30 per 100 000 (95% CI, 6.1-86.4) sampling on day 1; 33 per 100 000 (95% CI, 7-96) on day 7; and 40 per 100 000 (95% CI, 1.28-122.4) if the screening was based on taking both samples (day 1 and 7). Only one TP was detected in the pool testing. The time for detection among TPs on day 1 ranged between 30 and 134 h. The system is not considered practical for use as a routine screening method, as the time for detection is too long. Pool testing is insensitive. Faster screening methods or pathogen-inactivation systems are needed.

  11. Automation of the γ-ray spectroscopy counting system at the Dow Chemical Company Analytical Sciences Laboratory

    NASA Astrophysics Data System (ADS)

    Romick, J. D.; Rigot, W. L.; Morabito, P. L.; Quinn, T. J.; Kocher, C. W.; Duke, D. J.

    1994-12-01

    The neutron activation analysis group within the Analytical Sciences Laboratory analyzes 3000-5000 samples annually for a wide variety of analytes. Due to the high sample load, it is imperative that the gamma spectroscopy counting system be automated to maximize the efficiency of the system while ensuring the accuracy of the analyses. Using a Zymark robotic system, Compumotor drives, and DEC-based Canberra/Nuclear Data software we have automated sample changing, detector positioning, and data acquisition. Automation of these functions has resulted in a more consistent counting geometry, minimized crosstalk between samples, and accurate repositioning of the detectors for standardless quantitative analysis. The Zymark robotic system currently controls two detector systems, but is designed to control up to three independent detector systems. Canberra/Nuclear Data software, operating on a Microvax 3100, issues commands to the Zymark controller to change samples when spectral acquisition is complete. Once a new sample is in place, the robot sends a signal to the Microvax to begin data acquisition. Up to 40 samples, with sizes between 1 and 20 ml, can be accommodated using customized sample racks and sample holders. The location of the sample racks relative to the detectors has eliminated noticeable crosstalk between samples in the racks and samples being counted. The two HPGe detectors for each detector system sit on motorized platforms controlled by programmable Compumotor drives. Programmed function keys move the detectors in or out at fixed increments to optimize sample/detector geometry. The high resolution of the stepper motors enables accurate repositioning of detectors so that previously acquired standard spectra can be compared with samples activated and counted under identical conditions but at different times.

  12. Monitoring individual cow udder health in automated milking systems using online somatic cell counts.

    PubMed

    Sørensen, L P; Bjerring, M; Løvendahl, P

    2016-01-01

    This study presents and validates a detection and monitoring model for mastitis based on automated frequent sampling of online cell count (OCC). Initially, data were filtered and adjusted for sensor drift and skewed distribution using ln-transformation. Acceptable data were passed on to a time-series model using double exponential smoothing to estimate level and trends at cow level. The OCC levels and trends were converted to a continuous (0-1) scale, termed elevated mastitis risk (EMR), where values close to zero indicate healthy cow status and values close to 1 indicate high risk of mastitis. Finally, a feedback loop was included to dynamically request a time to next sample, based on latest EMR values or errors in the raw data stream. The estimated EMR values were used to issue 2 types of alerts, new and (on-going) intramammary infection (IMI) alerts. The new alerts were issued when the EMR values exceeded a threshold, and the IMI alerts were issued for subsequent alerts. New alerts were only issued after the EMR had been below the threshold for at least 8d. The detection model was evaluated using time-window analysis and commercial herd data (6 herds, 595,927 milkings) at different sampling intensities. Recorded treatments of mastitis were used as gold standard. Significantly higher EMR values were detected in treated than in contemporary untreated cows. The proportion of detected mastitis cases using new alerts was between 28.0 and 43.1% and highest for a fixed sampling scheme aiming at 24h between measurements. This was higher for IMI alerts, between 54.6 and 89.0%, and highest when all available measurements were used. The lowest false alert rate of 6.5 per 1,000 milkings was observed when all measurements were used. The results showed that a dynamic sampling scheme with a default value of 24h between measurements gave only a small reduction in proportion of detected mastitis treatments and remained at 88.5%. It was concluded that filtering of raw data

  13. Comparison study of membrane filtration direct count and an automated coliform and Escherichia coli detection system for on-site water quality testing.

    PubMed

    Habash, Marc; Johns, Robert

    2009-10-01

    This study compared an automated Escherichia coli and coliform detection system with the membrane filtration direct count technique for water testing. The automated instrument performed equal to or better than the membrane filtration test in analyzing E. coli-spiked samples and blind samples with interference from Proteus vulgaris or Aeromonas hydrophila.

  14. Acute subdural haemorrhage in the postpartum period as a rare manifestation of possible HELLP (haemolysis, elevated liver enzymes, and low-platelet count) syndrome: a case report

    PubMed Central

    2014-01-01

    Background The HELLP syndrome (haemolysis, elevated liver enzymes, and low-platelet count) occurs in about 0.5 to 0.9% of all pregnancies. With occurrence of thrombocytopaenia, it signals for several potentially lethal conditions such as complete or partial HELLP syndrome, thrombotic thrombocytopaenic purpura and acute fatty liver of pregnancy. Case presentation A previously healthy 27-year-old, Sinhala ethnic primigravida with pregnancy-induced hypertension was admitted at 38 weeks of gestation with lower abdominal pain and a blood pressure of 140/90 mmHg. She underwent emergency Caesarian section due to faetal distress giving birth to a healthy baby girl. Since postpartum day one, she was having intermittent fever spikes. All the routine investigations were normal in the first three weeks. Platelet count started dropping from post-partum day-20 onwards. On day-23, she had developed a seizure and computed tomography scan brain showed a subdural haemorrhage. She had a platelet count of 22,000 × 109/liter and was managed conservatively. She also had elevated liver enzymes, lactate dehydrogenase and bilirubin levels. Blood picture on day-24 showed haemolytic anemia. On day- 36, patient again developed seizures and she was having intermittent fever with generalized headache and signs of meningism. Computed tomography scan revealed an acute on chronic subdural haemorrhage. Conclusions Hypertensive disorders in pregnancy should be managed as high-risk throughout the postpartum period. Development of thrombocytopaenia can be considered as an early warning sign for HELLP, thrombotic thrombocytopaenic purpura or acute fatty liver of pregnancy which are lethal conditions. Prompt recognition of intracranial haemorrhages and early neurosurgical intervention is lifesaving. PMID:24972626

  15. Hormonal contraception and platelet function.

    PubMed

    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

  16. Clinical significance of the changes of platelet counts and serum thrombopoietin levels in chronic hepatitis C patients treated with different doses of consensus interferon.

    PubMed

    Chu, Chen Wei; Hwang, Shinn Jang; Lu, Rei Hwa; Lai, Chiung Ru; Luo, Jiing Chyuan; Wang, Yuan Jen; Chang, Full Young; Lee, Shou Dong

    2002-11-01

    Thrombocytopenia is commonly seen in patients with cirrhosis. Both splenomegaly and inadequate thrombopoietin (TPO) production by the cirrhotic liver are responsible for thrombocytopenia. In addition, thrombocytopenia is frequently observed in chronic hepatitis patients who received interferon therapy, and may even lead to the discontinuation of treatment. The aim of this study is to evaluate the clinical significance of the changes of platelet counts and serum TPO levels in chronic hepatitis C patients treated with different doses of consensus interferon (CIFN). Data from 75 chronic hepatitis C patients who received subcutaneous injection of either CIFN 9 (25 patients) or 3 &mgr;g (26 patients) or placebo (24 patients), three times a week for 24 weeks, were analyzed from a randomized controlled study. All patients received a 24-week observation period after the end of the treatment. The results showed a significantly higher degree of decrease in platelet counts and elevated serum TPO in patients receiving CIFN 9 or 3 &mgr;g as compared with placebo at week 12 and week 24 of treatment, respectively. These changes were more obvious in patients receiving CIFN 9 &mgr;g than in patients receiving CIFN 3 &mgr;g. However, both the decrease of platelet counts and elevated serum TPO levels returned to the baseline values after stopping CIFN therapy. Lower hepatic fibrosis score, lower pretreatment serum HCV RNA level, genotype non-1b infection and patients with sustained response to CIFN were manifested with higher degree of serum TPO elevation in response to the CIFN-induced thrombocytopenia. Multivariate logistic regression analysis showed that an age of less than 45 years and a serum TPO level elevation greater than 50% of baseline level at week 12 of CIFN treatment were significantly independent predictors associated with the sustained response to the CIFN treatment. In conclusion, the changes of platelet counts and serum TPO levels in chronic hepatitis C patients

  17. Design and Validation of an Augmented Hematopoietic Cell Transplantation-Comorbidity Index Comprising Pre-transplant Ferritin, Albumin and Platelet Count for Prediction of Outcomes after Allogeneic Transplantation

    PubMed Central

    Vaughn, Jennifer E.; Storer, Barry; Armand, Philippe; Raimondi, Roberto; Gibson, Christopher; Rambaldi, Alessandro; Ciceri, Fabio; Oneto, Rosi; Bruno, Benedetto; Martin, Paul J.; Sandmaier, Brenda M.; Storb, Rainer; Sorror, Mohamed L.

    2015-01-01

    Purpose Pre-transplant values of serum ferritin, albumin and peripheral blood counts were previously suggested to provide prognostic information about hematopoietic cell transplantation (HCT) outcomes. Whether these “biomarkers” have prognostic value independent of each other and the HCT-comorbidity index (HCT-CI) is unknown. Patients and Methods We analyzed data from 3917 allogeneic HCT recipients at multiple sites in the US and Italy using multivariate models including each biomarker and the HCT-CI. Data from all sites were then randomly divided into a training set (n=2352) to develop weights for the relevant biomarkers to be added to the HCT-CI scores and a validation set (n=1407) to validate an augmented HCT-CI compared to the original index. Results Multivariate analysis with data from one site showed that ferritin, albumin and platelets-- not neutrophils or hemoglobin--were independently associated with increased non-relapse mortality (NRM) and decreased overall survival. Findings were validated in data from the other sites. Subsequently, in a training set from all sites, ferritin >2500 mg/dL (HR:1.69); albumin 3–3.5 g/dL (HR:1.61) and <3.0 g/dL (HR:2.27); and platelets 50–<100,000 (HR:1.28), 20–<50,000 (HR:1.29) and <20,000 (HR:1.55) were statistically significantly associated with NRM. Weights were assigned to these laboratory values following the same equation used to design the original index. In the validation set, The addition of the biomarkers to the original index to develop an augmented HCT-CI resulted in a statistically significant increase in higher c-statistic estimate for prediction of NRM. (p=0.0007). Conclusion Ferritin, albumin, and platelet counts are important prognostic markers that further refine the discriminative power of the HCT-CI for transplant outcomes. PMID:25862589

  18. Design and Validation of an Augmented Hematopoietic Cell Transplantation-Comorbidity Index Comprising Pretransplant Ferritin, Albumin, and Platelet Count for Prediction of Outcomes after Allogeneic Transplantation.

    PubMed

    Vaughn, Jennifer E; Storer, Barry E; Armand, Philippe; Raimondi, Roberto; Gibson, Christopher; Rambaldi, Alessandro; Ciceri, Fabio; Oneto, Rosi; Bruno, Benedetto; Martin, Paul J; Sandmaier, Brenda M; Storb, Rainer; Sorror, Mohamed L

    2015-08-01

    Pretransplant values of serum ferritin, albumin, and peripheral blood counts were previously suggested to provide prognostic information about hematopoietic cell transplantation (HCT) outcomes. Whether these "biomarkers" have prognostic value independent of each other and the HCT-comorbidity index (HCT-CI) is unknown. We analyzed data from 3917 allogeneic HCT recipients at multiple sites in the United States and Italy using multivariate models including each biomarker and the HCT-CI. Data from all sites were then randomly divided into a training set (n = 2352) to develop weights for the relevant biomarkers to be added to the HCT-CI scores and a validation set (n = 1407) to validate an augmented HCT-CI compared with the original index. Multivariate analysis with data from one site showed that ferritin, albumin, and platelets-not neutrophils or hemoglobin-were independently associated with increased nonrelapse mortality (NRM) and decreased overall survival. Findings were validated in data from the other sites. Subsequently, in a training set from all sites, ferritin >2500 mg/dL (hazard ratio [HR], 1.69); albumin 3 to 3.5 g/dL (HR, 1.61) and <3.0 g/dL (HR, 2.27); and platelets 50 to <100,000 (HR, 1.28), 20 to <50,000 (HR, 1.29), and <20,000 (HR, 1.55) were statistically significantly associated with NRM. Weights were assigned to these laboratory values following the same equation used to design the original index. In the validation set, the addition of the biomarkers to the original index to develop an augmented HCT-CI resulted in a statistically significant increase in a higher c-statistic estimate for prediction of NRM (P = .0007). Ferritin, albumin, and platelet counts are important prognostic markers that further refine the discriminative power of the HCT-CI for transplant outcomes.

  19. Automated white blood cell counting via classification-free granulometric methods

    NASA Astrophysics Data System (ADS)

    Theera-Umpon, Nipon; Gader, Paul D.

    1999-03-01

    In this paper we describe an application of the granulometric mixing theorem to the problem of counting different types of white blood cells in bone marrow images. In principle, an iterative algorithm based on the mixing theorem can be used to count the proportion of cells in each class without explicitly segmenting and classifying them. The algorithm does not converge well for more than two classes. Therefore, a new algorithm based on the theorem is proposed. The proposed algorithm uses prior statistics to initially segment the mixed pattern spectrum and then applies the one-primitive mixing theorem to each initial component. Applying the mixing theorem to one class at a time results in better convergence. The counts produced by the proposed algorithm on 6 classes of cell -- Myeloblast, Promyelocyte, Myelocyte, Metamyelocyte, Band, and PMN -- are very close to the actual numbers; the deviation of the algorithm counts is not larger than deviation of counts produced by human experts. An important technical point is that, unlike previous algorithms, the proposed algorithm does not require prior knowledge of the total number of cells in an image.

  20. Espina: A Tool for the Automated Segmentation and Counting of Synapses in Large Stacks of Electron Microscopy Images

    PubMed Central

    Morales, Juan; Alonso-Nanclares, Lidia; Rodríguez, José-Rodrigo; DeFelipe, Javier; Rodríguez, Ángel; Merchán-Pérez, Ángel

    2011-01-01

    The synapses in the cerebral cortex can be classified into two main types, Gray's type I and type II, which correspond to asymmetric (mostly glutamatergic excitatory) and symmetric (inhibitory GABAergic) synapses, respectively. Hence, the quantification and identification of their different types and the proportions in which they are found, is extraordinarily important in terms of brain function. The ideal approach to calculate the number of synapses per unit volume is to analyze 3D samples reconstructed from serial sections. However, obtaining serial sections by transmission electron microscopy is an extremely time consuming and technically demanding task. Using focused ion beam/scanning electron microscope microscopy, we recently showed that virtually all synapses can be accurately identified as asymmetric or symmetric synapses when they are visualized, reconstructed, and quantified from large 3D tissue samples obtained in an automated manner. Nevertheless, the analysis, segmentation, and quantification of synapses is still a labor intensive procedure. Thus, novel solutions are currently necessary to deal with the large volume of data that is being generated by automated 3D electron microscopy. Accordingly, we have developed ESPINA, a software tool that performs the automated segmentation and counting of synapses in a reconstructed 3D volume of the cerebral cortex, and that greatly facilitates and accelerates these processes. PMID:21633491

  1. Analytic performance of the iQ200 automated urine microscopy analyzer and comparison with manual counts using Fuchs-Rosenthal cell chambers.

    PubMed

    Wah, David T; Wises, Porntip K; Butch, Anthony W

    2005-02-01

    Automated instruments that can examine urine for cells and particles have reduced the need for labor-intensive manual microscopy. We evaluated the performance of the Iris iQ200 Automated Urine Microscopy Analyzer (Iris Diagnostics, Chatsworth, CA) and compared results with manual cell and particle counts using Fuchs-Rosenthal counting chambers. Within-run imprecision (coefficient of variation) of the iQ200 for urine samples ranged from 3.0% to 45% for RBC counts between 1,029 and 3 x 10(6) cells/L, 3.4% to 40% for WBC counts between 1,006 and 4 x 10(6) cells/L, and 8.9% to 35% for epithelial cell counts between 93 and 4 x 10(6) cells/L. Between-run imprecision was 3.3% at 1,017 x 10(6) cells/L and 19.2% at 28 x 10(6) cells/L. There was good agreement between the iQ200 and manual cell counts (r > or = 0.94); however; the iQ200 produced lower results based on slopes of 0.92 (RBC count), 0.81 (WBC count), and 0.94 (epithelial cell counts). The iQ200 has satisfactory performance and correlates well with manual cell counts. Most urine samples containing RBCs, WBCs, and epithelial cells can be reported without review of captured images.

  2. AUTOMATED CELL COUNTING AND CLUSTER SEGMENTATION USING CONCAVITY DETECTION AND ELLIPSE FITTING TECHNIQUES

    PubMed Central

    Kothari, Sonal; Chaudry, Qaiser; Wang, May D

    2016-01-01

    This paper presents a novel, fast and semi-automatic method for accurate cell cluster segmentation and cell counting of digital tissue image samples. In pathological conditions, complex cell clusters are a prominent feature in tissue samples. Segmentation of these clusters is a major challenge for development of an accurate cell counting methodology. We address the issue of cluster segmentation by following a three step process. The first step involves pre-processing required to obtain the appropriate nuclei cluster boundary image from the RGB tissue samples. The second step involves concavity detection at the edge of a cluster to find the points of overlap between two nuclei. The third step involves segmentation at these concavities by using an ellipse-fitting technique. Once the clusters are segmented, individual nuclei are counted to give the cell count. The method was tested on four different types of cancerous tissue samples and shows promising results with a low percentage error, high true positive rate and low false discovery rate.

  3. Pretreatment platelet count improves the prognostic performance of the TNM staging system and aids in planning therapeutic regimens for nasopharyngeal carcinoma: a single-institutional study of 2,626 patients.

    PubMed

    Chen, Yu-Pei; Zhao, Bing-Cheng; Chen, Chen; Shen, Lu-Jun; Gao, Jin; Mai, Zhuo-Yao; Chen, Meng-Kun; Chen, Gang; Yan, Fang; Liu, Su; Xia, Yun-Fei

    2015-03-05

    Thrombocytosis has been identified as an unfavorable prognostic factor in several types of cancer. This study aimed to evaluate the prognostic value of pretreatment platelet count in association with the TNM staging system and therapeutic regimens in patients with nasopharyngeal carcinoma (NPC). A total of 2,626 patients with NPC were retrospectively analyzed. Platelet count >300 × 10(9)/L was defined as thrombocytosis. Matched-pair analysis was performed between patients receiving chemoradiotherapy and radiotherapy. Multivariate analysis showed that platelet count was an independent unfavorable prognostic factor for overall survival (OS) [hazard ratio (HR) = 1.810, 95% confidence interval (CI) = 1.531-2.140, P < 0.001] and distant metastasis-free survival (DMFS) (HR = 1.873, 95% CI = 1.475-2.379, P < 0.001) in the entire patient cohort. Further subgroup analysis revealed that increased platelet count was an independent unfavorable prognostic factor for OS and DMFS in patients with NPC stratified by early and advanced T category, N category, or TNM classification (all P ≤ 0.001). Receiver operating characteristic (ROC) curves verified that the predictive value of TNM classification for OS was improved when combined with pretreatment platelet count (P = 0.030). Matched-pair analysis showed that chemoradiotherapy significantly improved OS only in advanced-stage NPC with thrombocytosis (HR = 0.416, 95% CI = 0.226-0.765, P = 0.005). Pretreatment platelet count, when combined with TNM classification, is a useful indicator for metastasis and survival in patients with NPC. It may improve the predictive value of the TNM classification and help to identify patients likely to benefit from more aggressive therapeutic regimens.

  4. Past and future approaches to assess the quality of platelets for transfusion.

    PubMed

    Maurer-Spurej, Elisabeth; Chipperfield, Kate

    2007-10-01

    No automated test exists to routinely measure platelet quality. Currently, the short, 5-day shelf life of platelet concentrates is largely dictated by the risk associated with bacterial contamination and not by platelet quality. With the implementation of bacterial testing and pathogen inactivation, platelet quality will become the major determinant for the shelf life of platelet concentrates. However, extended use of platelet concentrates stored beyond 5 days will require quality testing. In addition, high platelet quality would be expected to result in improved clinical efficacy, determined by count increment, improved hemostasis, and lower risk for adverse reactions in recipients. No in vitro quality test has yet demonstrated a good correlation with clinical efficacy or improved hemostasis. This review focuses on those tests of platelet quality that are based on platelet morphology. These include visual inspection of swirling, microscopic morphology score, measurement of light transmission through platelet concentrates, and platelet light scattering techniques. Recently, a new test for platelet quality has been introduced that uses dynamic light scattering. The advantages and remaining challenges for dynamic light scattering before it can become a routine platelet quality test are discussed.

  5. ℮-conome: an automated tissue counting platform of cone photoreceptors for rodent models of retinitis pigmentosa

    PubMed Central

    2011-01-01

    Background Retinitis pigmentosa is characterized by the sequential loss of rod and cone photoreceptors. The preservation of cones would prevent blindness due to their essential role in human vision. Rod-derived Cone Viability Factor is a thioredoxin-like protein that is secreted by rods and is involved in cone survival. To validate the activity of Rod-derived Cone Viability Factors (RdCVFs) as therapeutic agents for treating retinitis Pigmentosa, we have developed e-conome, an automated cell counting platform for retinal flat mounts of rodent models of cone degeneration. This automated quantification method allows for faster data analysis thereby accelerating translational research. Methods An inverted fluorescent microscope, motorized and coupled to a CCD camera records images of cones labeled with fluorescent peanut agglutinin lectin on flat-mounted retinas. In an average of 300 fields per retina, nine Z-planes at magnification X40 are acquired after two-stage autofocus individually for each field. The projection of the stack of 9 images is subject to a threshold, filtered to exclude aberrant images based on preset variables. The cones are identified by treating the resulting image using 13 variables empirically determined. The cone density is calculated over the 300 fields. Results The method was validated by comparison to the conventional stereological counting. The decrease in cone density in rd1 mouse was found to be equivalent to the decrease determined by stereological counting. We also studied the spatiotemporal pattern of the degeneration of cones in the rd1 mouse and show that while the reduction in cone density starts in the central part of the retina, cone degeneration progresses at the same speed over the whole retinal surface. We finally show that for mice with an inactivation of the Nucleoredoxin-like genes Nxnl1 or Nxnl2 encoding RdCVFs, the loss of cones is more pronounced in the ventral retina. Conclusion The automated platform ℮-conome used

  6. Evaluation of the automated hematology analyzer Sysmex XT-2000iV™ compared to the ADVIA® 2120 for its use in dogs, cats, and horses: Part I--precision, linearity, and accuracy of complete blood cell count.

    PubMed

    Bauer, Natali; Nakagawa, Julia; Dunker, Cathrin; Failing, Klaus; Moritz, Andreas

    2011-11-01

    The automated laser-based hematology analyzer Sysmex XT-2000iV™ providing a complete blood cell count (CBC) and 5-part differential has been introduced in large veterinary laboratories. The aim of the current study was to determine precision, linearity, and accuracy of the Sysmex analyzer. Reference method for the accuracy study was the laser-based hematology analyzer ADVIA® 2120. For evaluation of accuracy, consecutive fresh blood samples from healthy and diseased cats (n = 216), dogs (n = 314), and horses (n = 174) were included. A low intra-assay coefficient of variation (CV) of approximately 1% was seen for the CBC except platelet count (PLT). An intra-assay CV ranging between 2% and 5.5% was evident for the differential count except for feline and equine monocytes (7.7%) and horse eosinophils (15.7%). Linearity was excellent for white blood cell count (WBC), hematocrit value, red blood cell count (RBC), and PLT. For all evaluated species, agreement was excellent for WBC and RBC, with Spearman rank correlation coefficients (r(s)) ranging from >0.99 to 0.98. Hematocrit value correlated excellently in cats and dogs, whereas for horses, a good correlation was evident. A good correlation between both analyzers was seen in feline and equine PLT (r(s) = 0.89 and 0.92, respectively), whereas correlation was excellent for dogs (r(s) = 0.93). Biases were close to 0 except for mean corpuscular hemoglobin concentration (4.11 to -7.25 mmol/l) and canine PLT (57 × 10(9)/l). Overall, the performance of the Sysmex analyzer was excellent and compared favorably with the ADVIA analyzer.

  7. Performance evaluation and result comparison of the automated hematology analyzers Abbott CD 3700, Sysmex XE 2100 and Coulter LH 750 for cell counts in serous fluids.

    PubMed

    Yang, Dagan; Zhou, Yunxian; Chen, Baode

    2013-04-18

    Automated hematology analyzers are used to perform cell counts in body fluids. However, little is known about how the results compare between different analyzers. A single batch of serous fluid samples was used to evaluate the cell counting performance of 3 hematology analyzers: CD 3700, XE 2100, and LH 750. Two hundred and seventy four serous fluid samples were used to evaluate the accuracy of the analyzers and to compare the results between different analyzers. The precision and linearity of the 3 analyzers were acceptable for both white blood cell counts and red blood cell counts with a low carryover rate. The limits of detection for white blood cells with the CD 3700, XE 2100, and LH 750 analyzers were 0.033×10(9)/l, 0.07×10(9)/l, and 0.20×10(9)/l, respectively. Performing background counts had no influence on cell counts for any of the analyzers. For those samples over the limit of detection, there was agreement between the automated and manual counting methods. There were also reasonably comparable cell count results between the 3 analyzers. When the serous fluid cell counts are over the limit of detection, the analyzers produce accurate test results. Additionally, the results are comparable between the 3 hematology analyzers. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Application of a portable microscopic cell counter for the counting of residual leukocytes in leukoreduced apheresis platelet concentrates in a hospital blood bank.

    PubMed

    Chun, Sejong; Kim, Eun-Young; Cha, Seung-Yeon; Seo, Ji-Young; Koo, Hong Hoe; Cho, Duck

    2017-06-01

    While a portable microscopic cell counter has been evaluated to enumerate residual white blood cells (WBCs) in red blood cells and platelet concentrates at blood centers, it has not yet been assessed in a hospital blood bank. We investigated the performance of this device and evaluated its accuracy, along with its benefits in time management. Residual WBCs from each of 100 apheresis platelet specimens were measured manually using a Nageotte chamber, along with flow cytometry methods and an ADAM-rWBC automated instrument (NanoEnTek, Seoul, South Korea). The efficiency was calculated by measuring the time required for the analysis of one specimen ten times consecutively. Flow cytometry and the ADAM-rWBC were able to detect four sporadic cases that had residual WBCs exceeding 1/μL that were not detected by the manual method. Analysis time was the shortest with the ADAM-rWBC, followed by flow cytometry and the manual method. Our data suggest that hospital blood banks require quality control of residual WBCs; among the methods evaluated in this study, the portable microscopic cell counter offers the best time efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Survey material choices in haematology EQA: a confounding factor in automated counting performance assessment

    PubMed Central

    De la Salle, Barbara

    2017-01-01

    The complete blood count (CBC) is one of the most frequently requested tests in laboratory medicine, performed in a range of healthcare situations. The provision of an ideal assay material for external quality assessment is confounded by the fragility of the cellular components of blood, the lack of commutability of stabilised whole blood material and the lack of certified reference materials and methods to which CBC results can be traced. The choice of assay material between fresh blood, extended life assay material and fully stabilised, commercially prepared, whole blood material depends upon the scope and objectives of the EQA scheme. The introduction of new technologies in blood counting and the wider clinical application of parameters from the extended CBC will bring additional challenges for the EQA provider. PMID:28392727

  10. Point-of-care ultrasonography of the orbit for detection of retinal detachment in a patient with hemolysis, elevated liver enzymes, and low platelet count syndrome

    PubMed Central

    Shrestha, Gentle Sunder; Rajbhandari, Shayuja; Dhungel, Shashwat; Sharma, Nutan; Poudel, Nimesh; Manandhar, Dhiraj N.

    2016-01-01

    Retinal detachment is a rare, but well-known cause of visual impairment in patients with hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. With supportive care, patients usually improve, with complete recovery of vision. Bedside ultrasonography of the orbit can be helpful for early detection of retinal detachment in these patients. Here, we present a case of HELLP syndrome presenting with severe visual symptoms. Retinal detachment was detected with point-of-care ocular sonography, which was confirmed with ophthalmoscopic examination. The patient was reassured of the favorable prognosis. Early initiation of aggressive supportive care was followed by progressive improvement of vision, which correlated with sonographic evidence of resolution of detachment. Her vision recovered completely in 2 weeks. PMID:27688632

  11. Retinal detachment in hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome: Color vision abnormality as the first and predominant manifestation.

    PubMed

    Morisawa, Hiroyuki; Makino, Shinji; Takahashi, Hironori; Sorita, Mari; Matsubara, Shigeki

    2015-11-01

    Serous retinal detachment is sometimes caused by hypertensive disorders in pregnancy and its associated conditions, in which the predominant eye symptoms are blurred vision, distorted vision, and reduced visual acuity. To our best knowledge, this is the first report of a puerperal woman with hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome in whom color vision abnormality was the first and predominant manifestation of serous retinal detachment. At 32 weeks of gestation, the 34-year-old Japanese woman underwent cesarean section due to HELLP syndrome. She complained of color vision abnormality on day 1 post-partum and ophthalmological examination revealed serous retinal detachment of both eyes. The visual acuity was preserved. With supportive therapy, her color vision abnormality gradually ameliorated and retinal detachment completely resolved on day 34 post-partum without any sequelae. Obstetricians should be aware that color vision abnormality can be the first and predominant symptom of HELLP-related serous retinal detachment.

  12. Evaluation of the 3D BacT/ALERT automated culture system for the detection of microbial contamination of platelet concentrates.

    PubMed

    McDonald, C P; Rogers, A; Cox, M; Smith, R; Roy, A; Robbins, S; Hartley, S; Barbara, J A J; Rothenberg, S; Stutzman, L; Widders, G

    2002-10-01

    Bacterial transmission remains the major component of morbidity and mortality associated with transfusion-transmitted infections. Platelet concentrates are the most common cause of bacterial transmission. The BacT/ALERT 3D automated blood culture system has the potential to screen platelet concentrates for the presence of bacteria. Evaluation of this system was performed by spiking day 2 apheresis platelet units with individual bacterial isolates at final concentrations of 10 and 100 colony-forming units (cfu) mL-1. Fifteen organisms were used which had been cited in platelet transmission and monitoring studies. BacT/ALERT times to detection were compared with thioglycollate broth cultures, and the performance of five types of BacT/ALERT culture bottles was evaluated. Sampling was performed immediately after the inoculation of the units, and 10 replicates were performed per organism concentration for each of the five types of BacT/ALERT bottles. The mean times for the detection of these 15 organisms by BacT/ALERT, with the exception of Propionibacterium acnes, ranged from 9.1 to 48.1 h (all 10 replicates were positive). In comparison, the time range found using thioglycollate was 12.0-32.3 h (all 10 replicates were positive). P. acnes' BacT/ALERT mean detection times ranged from 89.0 to 177.6 h compared with 75.6-86.4 h for the thioglycollate broth. BacT/ALERT, with the exception of P. acnes, which has dubious clinical significance, gave equivalent or shorter detection times when compared with the thioglycollate broth system. The BacT/ALERT system detected a range of organisms at levels of 10 and 100 cfu mL-1. This study validates the BacT/ALERT microbial detection system for screening platelets. Currently, the system is the only practically viable option available for routinely screening platelet concentrates to prevent bacterial transmission.

  13. Automated benthic counting of living and non-living components in Ngedarrak Reef, Palau via subsurface underwater video.

    PubMed

    Marcos, Ma Shiela Angeli; David, Laura; Peñaflor, Eileen; Ticzon, Victor; Soriano, Maricor

    2008-10-01

    We introduce an automated benthic counting system in application for rapid reef assessment that utilizes computer vision on subsurface underwater reef video. Video acquisition was executed by lowering a submersible bullet-type camera from a motor boat while moving across the reef area. A GPS and echo sounder were linked to the video recorder to record bathymetry and location points. Analysis of living and non-living components was implemented through image color and texture feature extraction from the reef video frames and classification via Linear Discriminant Analysis. Compared to common rapid reef assessment protocols, our system can perform fine scale data acquisition and processing in one day. Reef video was acquired in Ngedarrak Reef, Koror, Republic of Palau. Overall success performance ranges from 60% to 77% for depths of 1 to 3 m. The development of an automated rapid reef classification system is most promising for reef studies that need fast and frequent data acquisition of percent cover of living and nonliving components.

  14. Automated counting of morphologically normal red blood cells by using digital holographic microscopy and statistical methods

    NASA Astrophysics Data System (ADS)

    Moon, Inkyu; Yi, Faliu

    2015-09-01

    In this paper we overview a method to automatically count morphologically normal red blood cells (RBCs) by using off-axis digital holographic microscopy and statistical methods. Three kinds of RBC are used as training and testing data. All of the RBC phase images are obtained with digital holographic microscopy (DHM) that is robust to transparent or semitransparent biological cells. For the determination of morphologically normal RBCs, the RBC's phase images are first segmented with marker-controlled watershed transform algorithm. Multiple features are extracted from the segmented cells. Moreover, the statistical method of Hotelling's T-square test is conducted to show that the 3D features from 3D imaging method can improve the discrimination performance for counting of normal shapes of RBCs. Finally, the classifier is designed by using statistical Bayesian algorithm and the misclassification rates are measured with leave-one-out technique. Experimental results show the feasibility of the classification method for calculating the percentage of each typical normal RBC shape.

  15. Discovery of exacerbating cases in chronic hepatitis based on cluster analysis of time-series platelet count data

    NASA Astrophysics Data System (ADS)

    Hirano, Shoji; Tsumoto, Shusaku

    2007-04-01

    This paper reports the results of temporal analysis of platelet (PLT) data in chronic hepatitis dataset. First we briefly introduce a cluster analysis system for temporal data that we have developed. Second, we show the results of cluster analysis of PLT sequences. Third, we show the results of PLT value-based temporal analysis aiming at finding years for reaching F4, years elapsed between stages, and their relationships with virus types and fibrotic stages. The results of cluster analysis indicate that the temporal courses of PLT can be grouped into several patterns each of which presents similarity in average PLT level and increase/decrease trends. The results of value-based analysis suggests that liver fibrosis may proceed faster in the exacerbating cases.

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

    PubMed Central

    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. PMID:26829393

  17. Giant Platelets in Platelet Donors – A Blessing in Disguise?

    PubMed Central

    Choudhury, Nabajyoti; Ray, Deepanjan

    2015-01-01

    Introduction Inherited thrombocytopenias, including inherited giant platelet disorders (IGPD) are relatively rare, but their prevalence is probably underestimated. Harris platelet syndrome, the most common IGPD reported from Indian subcontinent, mostly from eastern part, is characterised by a low platelet count, high mean platelet volume (MPV) and absence of bleeding. Aim A short study was conducted to assess the prevalence of giant platelets in voluntary donors of single donor platelets (SDP) and analyse the effect of transfusion of such SDPs in patients. Materials and Methods Voluntary donors of SDPs were screened as per standard guidelines prior to the procedure. A complete blood count (including MPV) along with a peripheral smear was done. A total of 45 donors were screened for plateletpheresis. Following plateletpheresis from these donors, a platelet count from the collection bag was done after one hour. The SDP was transfused as a single unit or divided into two and transfused to the same patient at two different occasions, as per clinical need. Platelet counts on pateints were done after one hour and the platelet recovery was noted. Results Out of the 45 donors who were screened, 30 (66.67%) were found to have giant platelets. It was observed that the pre procedure platelet counts in donors having giant platelets were relatively low (1.5 -1.7 lacs) and so also the platelet yield (2.7-3x1011) compared to donors who did not, but the post transfusion platelet recovery was greater. Conclusion Since presence of giant platelets has been seen to be common in the Eastern part of India, a peripheral smear examination should always be considered during screening of plateletpheresis donors to avoid rejecting donors with giant platelets whose platelet counts are given falsely low by autoanalysers. PMID:26266124

  18. Could mean platelet volume among complete blood count parameters be a surrogate marker of metabolic syndrome in pre-pubertal children?

    PubMed

    Aypak, Cenk; Türedi, Ozlem; Bircan, Mustafa A; Yüce, Adnan

    2014-01-01

    Interest in childhood metabolic syndrome (MetS) has increased substantially due to the increasing prevalence of childhood obesity on a global scale. Early recognition of MetS is critical in order to delay the development of cardiovascular disease (CVD). In this study, we evaluated the relationship between complete blood count (CBC) parameters and MetS among pre-pubertal children which may provide evidence in support of using low cost, readily available clinical haematological parameters for the detection of MetS. A retrospective analysis was carried out on 330 (125 lean vs. 205 overweight) Turkish pre-pubertal children who attend to a paediatric outpatient clinic. Age, gender, puberty, body mass index, CBC parameters, cardiometabolic risk factors including lipid profiles, high sensitive serum reactive protein (hsCRP) and insulin resistance index calculated by homeostasis model assessment (HOMA-IR) were evaluated and compared among lean, overweight children and children with MetS. The mean age of the study population was 7.4 ± 1.9 years. In both gender, the mean values of mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were significantly lower and red blood cell (RBC), platelet (PLT) counts were significantly higher in overweight children. Overall, 8.4% (n = 28) of patients met the criteria of MetS. Children with MetS had higher levels of PLT and lower levels of mean platelet volume (MPV). Of all the haematological parameters analysed, PLT was positively, whereas MPV was negatively correlated with MetS in girls. In addition, MPV was inversely correlated with fasting blood glucose, HOMA-IR, low density lipoprotein-cholesterol (LDL-C) and low density lipoprotein-cholesterol/high density lipoprotein-cholesterol (LDL-C/HDL-C) ratio in girls after adjusting for confounding factors. The risk analyses of MetS in terms of MPV quartiles showed that the adjusted OR (95% CI) for the lowest vs. the

  19. Alloimmune refractoriness to platelet transfusions.

    PubMed

    Sandler, S G

    1997-11-01

    Patients who are transfused on multiple occasions with red cells or platelets may develop platelet-reactive alloantibodies and experience decreased clinical responsiveness to platelet transfusion. This situation, conventionally described as "refractoriness to platelet transfusions," is defined by an unsatisfactory low post-transfusion platelet count increment. If antibodies to HLAs are detected, improved clinical outcomes may result from transfusions of HLA-matched or donor-recipient cross-matched platelets. Because refractoriness is an expected, frequently occurring phenomenon, prevention of HLA alloimmunization is an important management strategy. Prevention strategies include efforts to decrease the number of transfusions, filtration of cellular components to reduce the number of HLA-bearing leukocytes, or pretransfusion ultraviolet B irradiation of cellular components to decrease their immunogenicity. Other investigational approaches include reducing the expression of HLAs on transfused platelets, inducing a transient reticuloendothelial system blockade by infusions of specialized immunoglobulin products, or transfusing semisynthetic platelet substitutes (thromboerythrocytes, thrombospheres) or modified platelets (infusible platelet membranes, lyophilized platelets).

  20. Platelet Count to Spleen Diameter Ratio for the Diagnosis of Gastroesophageal Varices in Liver Cirrhosis: A Systematic Review and Meta-Analysis

    PubMed Central

    Chen, Runhua; Deng, Han; Xie, Chune; Wang, Wei

    2017-01-01

    Platelet count to spleen diameter ratio (PSR) was studied extensively as a noninvasive method of diagnosis for varices. The present study aimed to systematically assess the performance of PSR in the diagnosis of varices. PubMed, EMBASE, and article references were searched. The summary receiver operating characteristic curves (AUSROCs), sensitivities, specificities, positive and negative likelihood ratio, and diagnostic odds ratio were calculated. The heterogeneity, quality, and publication bias of studies were evaluated. Subgroup and sensitivity analyses were performed. A total of 49 papers were included. The AUSROCs of PSR for any varices and high-risk varices were 0.8719 and 0.8132, respectively. The summary sensitivities of PSR for any varices and high-risk varices were 0.84 and 0.78, respectively. The summary specificities of PSR for any varices and high-risk varices were 0.78 and 0.67, respectively. The AUSROC of PSR for any varices at the threshold of 909 was 0.8867. The AUSROC of PSR for any varices in viral liver cirrhosis was 0.8675. The overall quality of studies was moderate. Significant heterogeneity and publication bias existed in the study. In conclusion, PSR can be used to identify varices in liver cirrhosis. PSR had a high sensitivity in viral liver cirrhosis. PMID:28270848

  1. RetFM-J, an ImageJ-based module for automated counting and quantifying features of nuclei in retinal whole-mounts.

    PubMed

    Hedberg-Buenz, Adam; Christopher, Mark A; Lewis, Carly J; Meyer, Kacie J; Rudd, Danielle S; Dutca, Laura M; Wang, Kai; Garvin, Mona K; Scheetz, Todd E; Abràmoff, Michael D; Harper, Matthew M; Anderson, Michael G

    2016-05-01

    The present article introduces RetFM-J, a semi-automated ImageJ-based module that detects, counts, and collects quantitative data on nuclei of the inner retina from H&E-stained whole-mounted retinas. To illustrate performance, computer-derived outputs were analyzed in inbred C57BL/6J mice. Automated characterization yielded computer-derived outputs that closely matched manual counts. As a method using open-source software that is freely available, inexpensive staining reagents that are robust, and imaging equipment that is routine to most laboratories, RetFM-J could be utilized in a wide variety of experiments benefiting from high-throughput, quantitative, uniform analyses of total cellularity in the inner retina.

  2. An Unusual Medicolegal Case of 32-Year-Old Mother and Her 29-Week Fetus With Hemolysis, Elevated Liver Enzymes, and Low Platelet Count Syndrome: Case Report and Short Literature Review.

    PubMed

    Szeremeta, Michał; Drobuliakova, Petra; Przepieść, Jerzy; Załuski, Janusz; Sackiewicz, Adam; Niemcunowicz-Janica, Anna

    2017-09-01

    Forensic medicine experts are well aware of blunt abdominal trauma, which often lead to death because of serious internal organ injury with severe blood loss. Sometimes careful examination of such cases may reveal some other underlying conditions, such as an existing disease that had contributed to the death or life-threatening complications. Our article presents a rare case of spontaneous hepatic rupture and intraperitoneal hemorrhage in a 32-year-old primigravida and her 29-week fetus, which was a result of hemolysis, elevated liver enzymes, and low platelet count syndrome. The said syndrome is a life-threatening obstetric complication usually considered to be a variant or complication of pre-eclampsia, which is characterized by hemolysis with microangiopathy, elevated liver enzymes, and low platelet count.

  3. To study the effects of gamma irradiation on single donor apheresis platelet units by measurement of cellular counts, functional indicators and a panel of biochemical parameters, in order to assess pre-transfusion platelet quantity and quality during the shelf life of the product

    PubMed Central

    Mallhi, R.S.; Biswas, A.K.; Philip, J.; Chatterjee, T.

    2016-01-01

    Background The occurrence of transfusion associated graft versus host disease can be prevented by gamma irradiation of blood components. This study was undertaken to assess the effects of gamma irradiation on single donor platelet (SDP) concentrate units. Method SDPs were collected by a continuous flow apheresis technique (n = 400). The SDPs from each donor were divided into two parts, one gamma-irradiated with 25 Gy and the other used as a non-irradiated control. Swirling and morphological features, cellular counts, biochemical parameters including blood gas analysis, and platelet activation levels (CD62P: p-selectin) by flow cytometry were analyzed on Day 1 and on Day 5. Results Swirling and morphology were maintained in all products, in both the groups throughout the shelf life. No significant change was seen in both groups, on the first and fifth day, as far as pO2, pCO2, Na+, K+, HCO3− & Ca2+ were concerned. However, lactate increased and glucose decreased significantly in irradiated products over 5-day storage period. A small but significant decrease in pH and platelet count was found in the irradiated PCs after 5-day storage. The mean proportion of platelets expressing CD62P over 5-day storage increased significantly. Conclusion After an overall assessment of all our in vitro parameter results and observations, a few of which were significant, while most were not significant, we concluded that a well-preserved quality of gamma irradiated apheresis platelets is maintained throughout the entire 5-day shelf life of the platelet product, with minimal difference compared to non-irradiated platelets. PMID:26900218

  4. Thrombocytopenia: A Destruction of Platelets.

    PubMed

    Greenberg, Edythe M

    Platelets, or megakaryocytes, are irregular, disk-shaped cell fragments circulating in the blood. They are a primary component in maintaining hemostasis. Low platelet counts, or thrombocytopenia, leave patients at an increased risk of hemorrhage. This article discusses various etiologies of disorders of low platelets and current therapies for management.

  5. A new colorimetrically-calibrated automated video-imaging protocol for day-night fish counting at the OBSEA coastal cabled observatory.

    PubMed

    del Río, Joaquín; Aguzzi, Jacopo; Costa, Corrado; Menesatti, Paolo; Sbragaglia, Valerio; Nogueras, Marc; Sarda, Francesc; Manuèl, Antoni

    2013-10-30

    Field measurements of the swimming activity rhythms of fishes are scant due to the difficulty of counting individuals at a high frequency over a long period of time. Cabled observatory video monitoring allows such a sampling at a high frequency over unlimited periods of time. Unfortunately, automation for the extraction of biological information (i.e., animals' visual counts per unit of time) is still a major bottleneck. In this study, we describe a new automated video-imaging protocol for the 24-h continuous counting of fishes in colorimetrically calibrated time-lapse photographic outputs, taken by a shallow water (20 m depth) cabled video-platform, the OBSEA. The spectral reflectance value for each patch was measured between 400 to 700 nm and then converted into standard RGB, used as a reference for all subsequent calibrations. All the images were acquired within a standardized Region Of Interest (ROI), represented by a 2 × 2 m methacrylate panel, endowed with a 9-colour calibration chart, and calibrated using the recently implemented "3D Thin-Plate Spline" warping approach in order to numerically define color by its coordinates in n-dimensional space. That operation was repeated on a subset of images, 500 images as a training set, manually selected since acquired under optimum visibility conditions. All images plus those for the training set were ordered together through Principal Component Analysis allowing the selection of 614 images (67.6%) out of 908 as a total corresponding to 18 days (at 30 min frequency). The Roberts operator (used in image processing and computer vision for edge detection) was used to highlights regions of high spatial colour gradient corresponding to fishes' bodies. Time series in manual and visual counts were compared together for efficiency evaluation. Periodogram and waveform analysis outputs provided very similar results, although quantified parameters in relation to the strength of respective rhythms were different. Results

  6. A New Colorimetrically-Calibrated Automated Video-Imaging Protocol for Day-Night Fish Counting at the OBSEA Coastal Cabled Observatory

    PubMed Central

    del Río, Joaquín; Aguzzi, Jacopo; Costa, Corrado; Menesatti, Paolo; Sbragaglia, Valerio; Nogueras, Marc; Sarda, Francesc; Manuèl, Antoni

    2013-01-01

    Field measurements of the swimming activity rhythms of fishes are scant due to the difficulty of counting individuals at a high frequency over a long period of time. Cabled observatory video monitoring allows such a sampling at a high frequency over unlimited periods of time. Unfortunately, automation for the extraction of biological information (i.e., animals' visual counts per unit of time) is still a major bottleneck. In this study, we describe a new automated video-imaging protocol for the 24-h continuous counting of fishes in colorimetrically calibrated time-lapse photographic outputs, taken by a shallow water (20 m depth) cabled video-platform, the OBSEA. The spectral reflectance value for each patch was measured between 400 to 700 nm and then converted into standard RGB, used as a reference for all subsequent calibrations. All the images were acquired within a standardized Region Of Interest (ROI), represented by a 2 × 2 m methacrylate panel, endowed with a 9-colour calibration chart, and calibrated using the recently implemented “3D Thin-Plate Spline” warping approach in order to numerically define color by its coordinates in n-dimensional space. That operation was repeated on a subset of images, 500 images as a training set, manually selected since acquired under optimum visibility conditions. All images plus those for the training set were ordered together through Principal Component Analysis allowing the selection of 614 images (67.6%) out of 908 as a total corresponding to 18 days (at 30 min frequency). The Roberts operator (used in image processing and computer vision for edge detection) was used to highlights regions of high spatial colour gradient corresponding to fishes' bodies. Time series in manual and visual counts were compared together for efficiency evaluation. Periodogram and waveform analysis outputs provided very similar results, although quantified parameters in relation to the strength of respective rhythms were different. Results

  7. Evaluation of a new generation of culture bottle using an automated bacterial culture system for detecting nine common contaminating organisms found in platelet components.

    PubMed

    Brecher, M E; Heath, D G; Hay, S N; Rothenberg, S J; Stutzman, L C

    2002-06-01

    An automated bacterial culture system (BacT/ALERT 3D, bioMérieux) has been previously validated with a variety of bacteria in platelets. The recovery of bacteria in platelets using a new generation of culture bottles that do not require venting and that use a liquid emulsion sensor was studied. Bacillus cereus, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Staphylococcus aureus, Staphylococcus epidermidis, Serratia marcescens, Streptococcus viridans, and Propionibacterium acnes isolates were inoculated into Day 2 platelets to concentrations of 10 and 100 CFU per mL. Samples were then studied with current and new aerobic, anaerobic, and pediatric bottles. All organisms, except P. acnes, were detected in a mean time of 9.2 to 20.4 (10 CFU/mL) or 8.7 to 18.6 (100 CFU/mL) hours. P. acnes was detected in a mean time of 69.2 (10 CFU/mL) or 66.0 (100 CFU/mL) hours. The 10-fold increase in inoculum was associated with a mean 9.2 percent difference in detection time. The aerobic, anaerobic, and pediatric bottles had a mean difference in detection time (hours) between the current and new bottles of 0.10 (p=0.61), 0.4 (p=0.38), and 1.0 (p < 0.001), respectively. No difference in detection time between the current and new aerobic and anaerobic bottles was demonstrated. The new pediatric bottles had a small but significant delay in detection.

  8. Blood Count Tests

    MedlinePlus

    ... white blood cells (WBC), and platelets. Blood count tests measure the number and types of cells in ... helps doctors check on your overall health. The tests can also help to diagnose diseases and conditions ...

  9. A shear gradient-activated microfluidic device for automated monitoring of whole blood haemostasis and platelet function.

    PubMed

    Jain, Abhishek; Graveline, Amanda; Waterhouse, Anna; Vernet, Andyna; Flaumenhaft, Robert; Ingber, Donald E

    2016-01-06

    Accurate assessment of blood haemostasis is essential for the management of patients who use extracorporeal devices, receive anticoagulation therapy or experience coagulopathies. However, current monitoring devices do not measure effects of haemodynamic forces that contribute significantly to platelet function and thrombus formation. Here we describe a microfluidic device that mimics a network of stenosed arteriolar vessels, permitting evaluation of blood clotting within small sample volumes under pathophysiological flow. By applying a clotting time analysis based on a phenomenological mathematical model of thrombus formation, coagulation and platelet function can be accurately measured in vitro in patient blood samples. When the device is integrated into an extracorporeal circuit in pig endotoxemia or heparin therapy models, it produces real-time readouts of alterations in coagulation ex vivo that are more reliable than standard clotting assays. Thus, this disposable device may be useful for personalized diagnostics and for real-time surveillance of antithrombotic therapy in clinic.

  10. A shear gradient-activated microfluidic device for automated monitoring of whole blood haemostasis and platelet function

    PubMed Central

    Jain, Abhishek; Graveline, Amanda; Waterhouse, Anna; Vernet, Andyna; Flaumenhaft, Robert; Ingber, Donald E.

    2016-01-01

    Accurate assessment of blood haemostasis is essential for the management of patients who use extracorporeal devices, receive anticoagulation therapy or experience coagulopathies. However, current monitoring devices do not measure effects of haemodynamic forces that contribute significantly to platelet function and thrombus formation. Here we describe a microfluidic device that mimics a network of stenosed arteriolar vessels, permitting evaluation of blood clotting within small sample volumes under pathophysiological flow. By applying a clotting time analysis based on a phenomenological mathematical model of thrombus formation, coagulation and platelet function can be accurately measured in vitro in patient blood samples. When the device is integrated into an extracorporeal circuit in pig endotoxemia or heparin therapy models, it produces real-time readouts of alterations in coagulation ex vivo that are more reliable than standard clotting assays. Thus, this disposable device may be useful for personalized diagnostics and for real-time surveillance of antithrombotic therapy in clinic. PMID:26733371

  11. Comparison between a new platelet count drop method PL-11, light transmission aggregometry, VerifyNow aspirin system and thromboelastography for monitoring short-term aspirin effects in healthy individuals.

    PubMed

    Guan, Jie; Cong, Yulong; Ren, Junwei; Zhu, Yuan; Li, Li; Deng, Xinli; Bai, Jie

    2015-01-01

    Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow™ aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100 mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5 ± 1 days, 8 ± 1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100 mg/d aspirin intake and began to recover during 4-6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r = 0.614, p < 0.01); PL-11 vs. VerifyNow (r = 0.829, p < 0.01); PL-11 vs. TEG (r = 0.697, p < 0.001). There was no significant bias between PL-11 and LTA at baseline (bias = 1.94%, p = 0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias = 24.02%, p < 0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA > 20%, the cut-off values for each method were, respectively: PL-11 > 50%, VerifyNow > 533 ARU, TEG > 60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays

  12. Automated cold temperature cycling improves in vitro platelet properties and in vivo recovery in a mouse model compared to continuous cold storage.

    PubMed

    Skripchenko, Andrey; Gelderman, Monique P; Awatefe, Helen; Turgeon, Annette; Thompson-Montgomery, Dedeene; Cheng, Chunrong; Vostal, Jaroslav G; Wagner, Stephen J

    2016-01-01

    Platelets (PLTs) stored at cold temperatures (CTs) for prolonged time have dramatically reduced bacterial growth but poor survival when infused. A previous study demonstrated that human PLTs stored with manual cycling between 4 °C (12 hr) and 37 °C (30 min) and infused into severe combined immunodeficient (SCID) mice had survivals similar to or greater than those stored at room temperature (RT). In this study, the in vitro and in vivo properties of PLTs stored in an automated incubator programmed to cycle between 5 °C (11 hr) and 37 °C (1 hr) were evaluated. A Trima apheresis unit (n = 12) was aliquoted (60 mL) in CLX bags. One sample was stored with continuous agitation (RT), a second sample was stored at 4-6 °C without agitation (CT), and a third sample was placed in an automated temperature cycler with 5 minutes of agitation during the warm-up period (thermocycling [TC]). PLTs were assayed for several relevant quality variables. On Day 7, PLTs were infused into SCID mice and in vivo recovery was assessed at predetermined time points after transfusion. The glucose consumption rate, morphology score, hypotonic shock recovery level, and aggregation levels were increased and mitochondrial reactive oxygen species accumulations were decreased in TC-PLTs compared to those of CT-PLTs. The pH and Annexin V binding were comparable to those of RT-PLTs. All TC-PLTs had greater recovery than CT-PLTs and were comparable to RT-PLTs. PLTs stored under automated TC conditions have improved in vivo recovery and improved results for a number of in vitro measures compared to CT-PLTs. © 2015 AABB.

  13. Impact of reticulated platelets on antiplatelet response to thienopyridines is independent of platelet turnover.

    PubMed

    Stratz, Christian; Nührenberg, Thomas; Amann, Michael; Cederqvist, Marco; Kleiner, Pascal; Valina, Christian M; Trenk, Dietmar; Neumann, Franz-Josef; Hochholzer, Willibald

    2016-10-28

    Reticulated platelets are associated with impaired antiplatelet response to thienopyridines. It is uncertain whether this interaction is caused by a decreased drug exposure due to high platelet turnover reflected by elevated levels of reticulated platelets or by intrinsic properties of reticulated platelets. This study sought to investigate if the impact of reticulated platelets on early antiplatelet response to thienopyridines is mainly caused by platelet turnover as previously suggested. Elective patients undergoing coronary intervention were randomised to loading with clopidogrel 600 mg or prasugrel 60 mg (n=200). Adenosine diphosphate (ADP)-induced platelet reactivity was determined by impedance aggregometry before, at 30, 60, 90, and 120 minutes and at day 1 after loading. Immature platelet count was assessed as marker of reticulated platelets by flow cytometry. Platelet reactivity increased with rising levels of immature platelet count in both groups. This effect was more distinctive in patients on clopidogrel as compared to patients on prasugrel. Overall, immature platelet count correlated well with on-treatment platelet reactivity at all time-points (p < 0.001). These correlations did not change over time in the entire cohort as well as in patients treated with clopidogrel or prasugrel indicating an effect independent of platelet turnover (comparison of correlations 120 minutes/day 1: p = 0.64). In conclusion, the association of immature platelet count with impaired antiplatelet response to thienopyridines is similar early and late after loading. This finding suggests as main underlying mechanism another effect of reticulated platelets on thienopyridines than platelet turnover.

  14. Platelet Count and Major Bleeding in Patients Receiving Vitamin K Antagonists for Acute Venous Thromboembolism, Findings From Real World Clinical Practice

    PubMed Central

    Giorgi-Pierfranceschi, Matteo; Di Micco, Pierpaolo; Cattabiani, Chiara; Guida, Anna; Pagán, Barbara; Morales, Maria del Valle; Salgado, Estuardo; Suriñach, José Maria; Tolosa, Carles; Monreal, Manuel

    2015-01-01

    Abstract The outcome of patients with acute venous thromboembolism (VTE) and abnormal platelet count (PlC) at baseline has not been consistently studied. In real-world clinical practice, a number of patients with abnormal PlC receive vitamin K antagonists (VKAs) to treat acute VTE despite their higher risk of bleeding. We used the Registro Informatizado de Enfermedad TromboEmbólica registry database to compare the rate of major bleeding in patients receiving VKA for long-term therapy of acute VTE according to PlC levels at baseline. Patients were categorized as having very low (<100,000/μL), low (100,000–150,000/μL), normal (150,000–300,000/μL), high (300,000–450,000/μL), or very high (>450,000/μL) PlC at baseline. Of 55,369 patients recruited as of January 2015, 37,000 (67%) received long-term therapy with VKA. Of these, 611 patients (1.6%) had very low PlC, 4006 (10.8%) had low PlC, 25,598 (69%) had normal PlC, 5801 (15.6%) had high PlC, and 984 (2.6%) had very high PlC at baseline. During the course of VKA therapy (mean, 192 days), there were no differences in the duration or intensity (as measured by international normalized ratio levels) of treatment between subgroups. The rate of major bleeding was 3.6%, 2.1%, 1.9%, 2.1%, and 3.7%, respectively, and the rate of fatal bleeding was 0.98%, 0.17%, 0.29%, 0.34%, and 0.50%, respectively. Patients with very low or very high PlC levels were more likely to have severe comorbidities. We found a nonlinear “U-shaped” relationship between PlC at baseline and major bleeding during therapy with VKA for VTE. Consistent alteration of PlC values at baseline suggested a greater frailty. PMID:26632687

  15. Platelet preservation: agitation and containers.

    PubMed

    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.

  16. Application of the ADVIA cerebrospinal fluid assay to count residual red blood cells in blood components.

    PubMed

    Culibrk, B; Stone, E; Levin, E; Weiss, S; Serrano, K; Devine, D V

    2012-10-01

    There is no automated, accurate assay for the enumeration of residual red blood cells (rRBCs) in non-RBC components for transfusion, despite the potential risk of allo-immunization when mismatched components are transfused. The automated ADVIA 120 cerebrospinal fluid (CSF) assay, which is approved to count RBCs and WBCs in CSF samples, was optimized and tested to measure rRBC in platelet concentrate (PC) and plasma components. Sample dilution, incubation time and reagent volume were optimized for use with non-RBC blood products. The assay was linear (R(2) = 0·99), even at low rRBCs counts. Intra- and inter-assay variation gave coefficients of variance (CV) between 2·2 and 9·4% and 2·6 and 14·9%, respectively, depending on rRBC levels. Good correlation (r = 0·995) was found between the automated assay and manual counting, which is considered the gold standard. Using the automated assay, the range of rRBCs (count/unit) in buffy-coat platelet concentrate (PCs) was 27-5505 × 10(6) and in apheresis PCs was 1-361 × 10(6). The ADVIA CSF assay is a sensitive, precise and accurate means to assess rRBC counts in non-RBC components. © 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.

  17. Leukoreduction of platelet concentrates using a 'polishing' filter.

    PubMed

    van der Meer, P F; Pietersz, R N; Reesink, H W

    2000-01-01

    Filters for removal of leukocytes from platelet concentrates (PCs) usually have a large volume to guarantee sufficient leukoreduction. In this study, a small filter, with a volume of only 8 ml and therefore minimal platelet loss, for leukoreduction of PCs was investigated. This filter has a 'limited' leukoreducing capacity, hence the filter is called a 'polishing' filter. PCs were made from 5 pooled buffy coats in either plasma or additive solution (PAS-II). After centrifugation, the platelet-rich supernatant was expressed on an automated separator (Compomat G4) to an empty transfer bag. The content of this transfer bag was filtered into the platelet storage bag, either by expression by lowering the top press of the Compomat G4, or by gravity by hanging it on a filtration rack. Leukocyte counts before and after filtration revealed a mean leukoreducing capacity for the filter of 2.67 log(10) and a platelet loss of only 2% for PCs in PAS-II (n = 50), and for PCs in plasma a 3.43 log(10) leukoreduction with 3% platelet loss (n = 30). Expression of the PCs both in plasma and PAS-II through the filter using the Compomat G4 resulted in 10/10 units containing <5x10(6) leukocytes, but 1/10 PCs contained >1x10(6) leukocytes for both solutions. Filtration by gravity resultet in 40/40 units with <1x10(6) leukocytes for PCs in plasma, and 60/60 units with <1x10(6) for PCs in PAS-II. The 'polishing' filter allows reliable, standardized and automated production of PCs, both in plasma and additive solution with minimal platelet loss, and containing uniformly <1x10(6) leukocytes, provided the filtration procedure is performed by gravity.

  18. Mean platelet volume as an indicator of platelet rejuvenation following bone-marrow transplantation. Master's thesis

    SciTech Connect

    Seanger, D.G.

    1986-07-01

    Thrombocytopenia of unpredictable duration and severity is an expected outcome of the radiation/chemotherapy protocols performed prior to bone-marrow transplantation. Serial evaluation of the platelet count and mean platelet volume of patients diagnosed with acute leukemia demonstrated the mean platelet volume to increase into reference limits 24 to 40 hours prior to a rise in the platelet count in those patients whose bone-marrow successfully responded to induction chemotherapy. Serial platelet counts and measurements of mean platelet volume were performed on 31 patients following bone marrow transplantation. Numerous platelet transfusions, together with sustained thrombocytopenia, inhibited accurate assessment of 29 of 31 patients. Two patients, however, demonstrated a rise in the mean platelet volume prior to an increase in the platelet count. Both of these patients received no platelet transfusions during the period preceding or following the rise in the platelet count. It was proposed that the serial evaluation of the mean platelet volume may assist practitioners in the decision-making process of deciding whether platlet transfusions are required, or an increase in the number of circulating platelets is imminent. A decision not to transfuse would have the direct benefit of decreasing patient costs, in conjunction with eliminating a potential source for the development of an antibody against platelets.

  19. Minimal dose interferon suppository treatment suppresses viral replication with platelet counts and serum albumin levels increased in chronically hepatitis C virus-infected patients: a phase 1b, placebo-controlled, randomized study.

    PubMed

    Haruna, Yoshimichi; Inoue, Atsuo

    2014-02-01

    Animal studies have shown that rectally administrated interferon (IFN) is transferred into the lymphatic system via the rectal mucous membrane, suggesting that an IFN suppository could serve as another drug delivery method. We developed an IFN suppository and administered it to patients with chronic hepatitis C to evaluate its efficacy and safety. Twenty-eight patients with chronic hepatitis C participated in the study. The low-dose IFN suppository containing 1,000 international units (IU) of lymphoblastoid IFNα was administered to 14 patients daily for 24 weeks. Others had a placebo dosing. In 13 of the 14 IFN suppository-treated patients, viral load decreased at week 4. The serum hepatitis C virus (HCV) RNA levels (Log IU/mL, mean±standard error) were 5.65±0.18 before the treatment and 5.17±0.27 at week 4 (P=0.01). The 2'-5' oligoadenylate synthetase activity increased, while the CD4/CD8 ratio decreased significantly. Interestingly, platelet counts and serum albumin levels were significantly increased during and after the treatment. No serious adverse events were observed. The low-dose IFN suppository treatment suppressed HCV replication, modifying host immunity, with increased platelet counts and serum albumin levels. The IFN suppository could be considered a new drug delivery method to preserve the quality of life of patients.

  20. Mechanisms of hemolysis-associated platelet activation

    PubMed Central

    Helms, C. C.; Marvel, M.; Zhao, W.; Stahle, M.; Vest, R.; Kato, G. J.; Lee, J. S.; Christ, G.; Gladwin, M. T.; Hantgan, R. R.; Kim-Shapiro, D. B.

    2013-01-01

    Summary Background Intravascular hemolysis occurs after blood transfusion, in hemolytic anemias and other conditions, and is associated with hypercoagulable states. Hemolysis has been shown to potently activate platelets in vitro and in vivo and several mechanisms have been suggested to account for this including (1) direct activation by hemoglobin, (2) increase in reactive oxygen species (ROS), (3) scavenging of nitric oxide by released hemoglobin, and (4) release of intraerythrocytic ADP. Objective The aim of the current study is to elucidate the mechanism of hemolysis-mediated platelet activation. Methods We used flow cytometry to detect PAC-1 binding to activated platelets for in vitro experiments and a Siemens’ Advia 120 hematology system to assess platelet aggregation using platelet counts from in vivo experiments in a rodent model. Results We show that Hb does not directly activate platelets. However, ADP bound to Hb can cause platelet activation. Furthermore, platelet activation due to shearing of RBCs is reduced in the presence of apyrase which metabolizes ADP to AMP. Use of ROS scavengers did not affect platelet activation. We also show that cell free Hb does enhance platelet activation by abrogating the inhibitory effect of NO on platelet activation. In vivo infusions of ADP and purified (ADP-free) Hb as well as hemolysate result in platelet aggregation as evidenced by decreased platelet counts. Conclusion Two primary mechanisms account for red blood cell hemolysis-associated platelet activation: ADP release which activates platelets and cell-free hemoglobin release which enhances platelet activation by lowering NO bioavailability. PMID:24119131

  1. Platelets in Critical Illness.

    PubMed

    Levi, Marcel

    2016-04-01

    In patients with critical illness, thrombocytopenia is a frequent laboratory abnormality. However frequent this may occur, a low platelet count is not an epiphenomenon, but a marker with further significance. It is always important to assess the proper cause for thrombocytopenia in critically ill patients because different underlying disorders may precipitate different diagnostic and therapeutic management strategies. Platelets are part of the first-line defense of the body against bleeding; hence, thrombocytopenia may increase the risk of hemorrhage. In case of systemic inflammatory syndromes, such as the response to sepsis, disseminated intravascular platelet activation may occur. This will contribute to microvascular failure and thereby play a role in the development of organ dysfunction. Platelets are circulating blood cells that will normally not interact with the intact vessel wall but that may swiftly respond to endothelial disruption (which is often part of the pathogenesis of critical illness) by adhering to subendothelial structures, followed by interaction with each other, thereby forming a platelet aggregate. The activated platelet (phospholipid) membrane may form a suitable surface on which further coagulation activation may occur. A low platelet count is a strong and independent predictor of an adverse outcome in critically ill patients, thereby facilitating a simple and practically risk assessment in these patients and potentially guiding the use of complex or expensive treatment strategies.

  2. Changes in platelet parameters in leukocytosis.

    PubMed

    Ozturk, Nurinnisa; Baygutalp, Nurcan Kilic; Bakan, Ebubekir; Altas, Gulsum Feyza; Polat, Harun; Dorman, Emrullah

    2016-01-01

    In recent years, platelets are known to have a large variety of functions in many pathophysiological processes and their interaction with endothelial cells and leukocytes is known to play an important role in the pathophysiology of vascular inflammation. The aim of this study was to investigate the relationship between white blood cell count in conditions resulting in leukocytosis and platelet count and platelet parameters including mean platelet volume, platelet distribution width, and plateletcrit. White blood cell counts count and all platelet parameters were evaluated in 341 results of normal complete blood count (of which the white blood cell counts were within reference range, group 1) and 327 results of elevated white blood cell counts count (group 2). There was a significant difference between these two groups in PLT counts and PCT values, being higher in Group 2. However, there was no statistically significant difference between two groups in MPV and PDW values. On the other hand, there were statistically significant, but weak, correlations between the WBC and platelet counts in both groups (p<0.01, r=0.235 for group 1, p<0.05, r=0.116 for group 2). As a conclusion PLT count and PCT values increase in infectious conditions. This study and previous studies show that PLTs are employed in infectious conditions but the exact mechanism and the exact clinical importance of this response remains to be cleared by further studies.

  3. Autologous platelet-labeling in thrombocytopenia

    SciTech Connect

    Sinzinger, H.; Virgolini, I.; Vinazzer, H. )

    1990-11-01

    Field studies performed with peripheral platelets obtained from 6 male volunteers aged 23 to 29 years revealed an extraordinary dependence of labeling efficiency on incubation time and platelet concentration after {sup 111}In-oxine platelet labeling. Since the monitoring of in vivo-platelet function in patients with thrombocytopenia may cause problems due to insufficient labeling results and homologous platelets may show a different in vivo behaviour to autologous ones, we have searched for the minimal amount of platelets necessary to allow appropriate labeling and imaging in patients with thrombocytopenia. In 15 patients with untreated thrombocytopenia aged 14 to 79 years demonstrating a mean peripheral platelet count of 2.509 +/- 1.45 x 10(4) cells/microliters autologous {sup 111}In-oxine platelet labeling was performed. The results indicate that approximately 1 x 10(8) (concentrated) platelets/ml are necessary to obtain an adequate labeling efficiency and recovery. This platelet concentration can be easily achieved by drawing one more Monovette of whole blood per each 5 x 10(4) platelets/microliter peripheral platelet count less than 2 x 10(5)/microliter. It is concluded, that calculation of the required number of platelets in advance, variation of the blood volume drawn and the volume of incubation buffer allow informative, qualitative and quantitative results using autologous platelets. The method presented effectively circumvents the requirement of homologous platelets for radiolabeling in thrombocytopenia.

  4. Comparison of point-of-care methods for preparation of platelet concentrate (platelet-rich plasma).

    PubMed

    Weibrich, Gernot; Kleis, Wilfried K G; Streckbein, Philipp; Moergel, Maximilian; Hitzler, Walter E; Hafner, Gerd

    2012-01-01

    This study analyzed the concentrations of platelets and growth factors in platelet-rich plasma (PRP), which are likely to depend on the method used for its production. The cellular composition and growth factor content of platelet concentrates (platelet-rich plasma) produced by six different procedures were quantitatively analyzed and compared. Platelet and leukocyte counts were determined on an automatic cell counter, and analysis of growth factors was performed using enzyme-linked immunosorbent assay. The principal differences between the analyzed PRP production methods (blood bank method of intermittent flow centrifuge system/platelet apheresis and by the five point-of-care methods) and the resulting platelet concentrates were evaluated with regard to resulting platelet, leukocyte, and growth factor levels. The platelet counts in both whole blood and PRP were generally higher in women than in men; no differences were observed with regard to age. Statistical analysis of platelet-derived growth factor AB (PDGF-AB) and transforming growth factor β1 (TGF-β1) showed no differences with regard to age or gender. Platelet counts and TGF-β1 concentration correlated closely, as did platelet counts and PDGF-AB levels. There were only rare correlations between leukocyte counts and PDGF-AB levels, but comparison of leukocyte counts and PDGF-AB levels demonstrated certain parallel tendencies. TGF-β1 levels derive in substantial part from platelets and emphasize the role of leukocytes, in addition to that of platelets, as a source of growth factors in PRP. All methods of producing PRP showed high variability in platelet counts and growth factor levels. The highest growth factor levels were found in the PRP prepared using the Platelet Concentrate Collection System manufactured by Biomet 3i.

  5. Physiologic and pathologic changes of platelets in pregnancy.

    PubMed

    Valera, Marie-Cecile; Parant, Olivier; Vayssiere, Christophe; Arnal, Jean-François; Payrastre, Bernard

    2010-01-01

    Platelets are key players in haemostasis and thrombus formation. Defects affecting platelets during pregnancy can lead to heterogeneous complications, such as thrombosis, first trimester miscarriage and postpartum haemorrhage. The incidence of complications is increased in women who have heritable platelet function disorders. Modifications of platelet count or platelet functions during normal pregnancy and preeclampsia will be summarized and the management of pregnant women with heritable platelet function disorders will be discussed.

  6. Unraveling mechanisms that control platelet production.

    PubMed

    Italiano, Joseph E

    2013-02-01

    Platelets are formed by giant precursor cells called megakaryocytes that reside within the bone marrow. The generation of platelets, and their release into the bloodstream by megakaryocytes, requires a complex series of remodeling events powered by the cytoskeleton to result in the release of many platelets from a single megakaryocyte. Abnormalities in this process can result in thrombocytopenia (low platelet count) and can lead to increased risk of bleeding. This review describes the process of platelet production in detail and discusses new insights into novel platelet biology. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  7. Automated five-part white blood cell differential counts. Efficiency of software-generated white blood cell suspect flags of the hematology analyzers Sysmex SE-9000, Sysmex NE-8000, and Coulter STKS.

    PubMed

    Thalhammer-Scherrer, R; Knöbl, P; Korninger, L; Schwarzinger, I

    1997-06-01

    The present study evaluates the efficiency of software-generated white blood cell (WBC) "suspect flags" of the hematology analyzers Sysmex SE-9000, Sysmex NE-8000, and Coulter STKS. Automated WBC differential counts were considered positive if they contained any suspect WBC flag indicating the presence of blasts, myeloid precursor cells, or abnormal lymphocytes. Reference differential counts were performed by microscopic examination of 400 WBCs per sample. After comparison to the reference method, automated differential counts were classified as true-positive, true-negative, false-positive, and false-negative. The flagging efficiency of analyzers was expressed as a percentage of subjects correctly classified. Four hundred sixty-seven blood samples were randomly chosen for comparison analysis from various inpatient and outpatient departments of the Vienna university hospital, Austria. The efficiency rates of flagging for the presence of > or = 1% abnormal WBCs were 78% (SE-9000), 77% (NE-8000), and 72% (Coulter STKS). The flagging efficiencies were best for samples with normal WBC counts. With regard to the specific suspect flags, the flagging of blast cells was most efficient on all analyzers. Our results demonstrate the comparable overall performance of three analyzers, SE-9000, NE-8000, and Coulter STKS. They further underscore the importance of critical interpretation of automated differential counts, because at a detection limit of > or = 1% abnormal WBCs > 20% of samples were not correctly flagged by either analyzer.

  8. Low local blood perfusion, high white blood cell and high platelet count are associated with primary tumor growth and lung metastasis in a 4T1 mouse breast cancer metastasis model.

    PubMed

    Wang, Chuan; Chen, Ying-Ge; Gao, Jian-Li; Lyu, Gui-Yuan; Su, Jie; Zhang, Q I; Ji, Xin; Yan, Ji-Zhong; Qiu, Qiao-Li; Zhang, Yue-Li; Li, Lin-Zi; Xu, Han-Ting; Chen, Su-Hong

    2015-08-01

    It was originally thought that no single routine blood test result would be able to indicate whether or not a patient had cancer; however, several novel studies have indicated that the median survival and prognosis of cancer patients were markedly associated with the systemic circulation features of cancer patients. In addition, certain parameters, such as white blood cell (WBC) count, were largely altered in malignant tumors. In the present study, routine blood tests were performed in order to observe the change of blood cells in tumor-bearing mice following the implantation of 4T1 breast cancer cells into the mammary fat pad; in addition, blood flow in breast tumor sites was measured indirectly using laser Doppler perfusion imaging (LDPI), in an attempt to explain the relevance between the blood circulation features and the growth or metastasis of breast cancer in mice model. The LDPI and blood test results indicated that the implantation of 4T1 breast cancer cells into BALB/c mice led to thrombosis as well as high WBC count, high platelet count, high plateletcrit and low blood perfusion. Following implantation of the 4T1 cells for four weeks, the lung metastatic number was determined and the Pearson correlation coefficient revealed that the number of visceral lung metastatic sites had a marked negative association with the ratio of basophils (BASO%; r=-0.512; P<0.01) and the mean corpuscular hemoglobin was significantly correlated with primary tumor weight (r=0.425; P<0.05). In conclusion, the results of the present study demonstrated that tumor growth led to thrombosis and acute anemia in mice; in addition, when blood BASO% was low, an increased number of lung metastases were observed in tumor-bearing mice.

  9. Platelet Donation

    MedlinePlus

    ... donating platelets, can I still donate blood? What blood types should donate platelets? Can I donate plasma at ... Community Learn About Blood Blood Facts and Statistics Blood Types Blood Components What Happens to Donated Blood Blood ...

  10. The biogenesis of platelets from megakaryocyte proplatelets

    PubMed Central

    Patel, Sunita R.; Hartwig, John H.; Italiano, Joseph E.

    2005-01-01

    Platelets are formed and released into the bloodstream by precursor cells called megakaryocytes that reside within the bone marrow. The production of platelets by megakaryocytes requires an intricate series of remodeling events that result in the release of thousands of platelets from a single megakaryocyte. Abnormalities in this process can result in clinically significant disorders. Thrombocytopenia (platelet counts less than 150,000/μl) can lead to inadequate clot formation and increased risk of bleeding, while thrombocythemia (platelet counts greater than 600,000/μl) can heighten the risk for thrombotic events, including stroke, peripheral ischemia, and myocardial infarction. This Review will describe the process of platelet assembly in detail and discuss several disorders that affect platelet production. PMID:16322779

  11. Leukocyte Count and Intracerebral Hemorrhage Expansion.

    PubMed

    Morotti, Andrea; Phuah, Chia-Ling; Anderson, Christopher D; Jessel, Michael J; Schwab, Kristin; Ayres, Alison M; Pezzini, Alessandro; Padovani, Alessandro; Gurol, M Edip; Viswanathan, Anand; Greenberg, Steven M; Goldstein, Joshua N; Rosand, Jonathan

    2016-06-01

    Acute leukocytosis is a well-established response to intracerebral hemorrhage (ICH). Leukocytes, because of their interaction with platelets and coagulation factors, may in turn play a role in hemostasis. We investigated whether admission leukocytosis was associated with reduced bleeding after acute ICH. Consecutive patients with primary ICH were prospectively collected from 1994 to 2015 and retrospectively analyzed. We included subjects with a follow-up computed tomographic scan available and automated complete white blood cell count performed within 48 hours from onset. Baseline and follow-up hematoma volumes were calculated with semiautomated software, and hematoma expansion was defined as volume increase >30% or 6 mL. The association between white blood cell count and ICH expansion was investigated with multivariate logistic regression. A total of 1302 subjects met eligibility criteria (median age, 75 years; 55.8% men), of whom 207 (15.9%) experienced hematoma expansion. Higher leukocyte count on admission was associated with reduced risk of hematoma expansion (odds ratio for 1000 cells increase, 0.91; 95% confidence interval, 0.86-0.96; P=0.001). The risk of hematoma expansion was inversely associated with neutrophil count (odds ratio, 0.90; 95% confidence interval, 0.85-0.96; P=0.001) and directly associated with monocyte count (odds ratio, 2.71; 95% confidence interval, 1.08-6.83; P=0.034). There was no association between lymphocyte count and ICH expansion (odds ratio, 0.96; 95% confidence interval, 0.79-1.17; P=0.718). Higher admission white blood cell count is associated with lower risk of hematoma expansion. This highlights a potential role of the inflammatory response in modulating the coagulation cascade after acute ICH. © 2016 American Heart Association, Inc.

  12. Regulating billions of blood platelets: glycans and beyond

    PubMed Central

    Grozovsky, Renata; Giannini, Silvia; Falet, Hervé

    2015-01-01

    The human body produces and removes 1011 platelets daily to maintain a normal steady state platelet count. Platelet production must be regulated to avoid spontaneous bleeding or arterial occlusion and organ damage. Multifaceted and complex mechanisms control platelet production and removal in physiological and pathological conditions. This review will focus on different mechanisms of platelet senescence and clearance with specific emphasis on the role of posttranslational modifications. It will also briefly address platelet transfusion and the role of glycans in the clearance of stored platelets. PMID:26330242

  13. [The estimation of the number of platelets by different methods].

    PubMed

    Ratomski, Karol; Zak, Janusz; Kasprzycka, Edwina; Hryniewicz, Katarzyna; Wysocka, Jolanta

    2010-05-01

    The commonly available and accurate platelet counts play an important role in the evaluation of haemorrhagic status and in assessing the need for platelet transfusions. We evaluated platelet counting performance by the Sysmex XT-2000i haematology analyser and by the Coulter EPICS XL cytometry using optical, impedance and immunological methods in trombocytopenic patients. Hematology analysers display the high precision and the accuracy of the measurement of the number of platelets in whole blood. However, the measurement of number of platelets can be disturbed by the presence of interference factors such as: microcytic erytrocytes, schizocytes, cryoglobulins, microplatelets and immunological clumps. The comparison of impedance, optical and immunological enumeration methods of platelets by the Sysmex XT-2000i haematology analyser and by the Coulter EPICS XL cytometer. The platelet count of all considered methods showed good correlation with the cytometric method. Only cytometric method with using anti-CD41 monoclonal antibody allowed to verify the results of enumeration methods of platelets.

  14. Mean Platelet Volume, a Novel Biomarker in Adolescents with Severe Primary Dysmenorrhea.

    PubMed

    Kabil Kucur, Suna; Seven, Ali; Yuksel, Kadriye Beril; Sencan, Halime; Gozukara, Ilay; Keskin, Nadi

    2016-08-01

    To evaluate whether mean platelet volume (MPV) would be a profitable marker in predicting disease severity in adolescents with severe primary dysmenorrhea (PD). DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: A total of 67 patients diagnosed with PD and 37 healthy adolescents with regular menstrual cycles were included in the study. Hemoglobin, MPV, and white blood cell, platelet, lymphocyte, and neutrophil counts were measured as part of the automated complete blood examination. Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio were obtained from the absolute neutrophil or platelet count, respectively, divided by the absolute lymphocyte count. The visual analog scale was used to assess the level of pain, as mild (<40 mm), moderate (40-60 mm) and severe (>60 mm) PD. The MPV level of the combined severity of PD and control groups were similar. However, the MPV was significantly lower in the severe PD group compared with the control group (P = .04). There were no significant differences in the other hematological parameters between the groups. The mean visual analog scale score of the PD and control subjects were 7.35 ± 2.25 and 1.07 ± 1.96, respectively (P < .01). There was a poor negative correlation, which was statistically insignificant, between MPV and white blood cell count. The present study showed that MPV is decreased in adolescents with severe PD. Further studies with larger numbers of subjects are necessary to clarify the roles of platelets in the pathogenesis of severe PD and evaluate the changes in MPV value in response to treatment. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  15. Expansion of the neonatal platelet mass is achieved via an extension of platelet lifespan

    PubMed Central

    Liu, Zhi-Jian; Hoffmeister, Karin M.; Hu, Zhongbo; Mager, Donald E.; Ait-Oudhia, Sihem; Debrincat, Marlyse A.; Pleines, Irina; Josefsson, Emma C.; Kile, Benjamin T.; Italiano, Joseph; Ramsey, Haley; Grozovsky, Renata; Veng-Pedersen, Peter; Chavda, Chaitanya

    2014-01-01

    The fetal/neonatal hematopoietic system must generate enough blood cells to meet the demands of rapid growth. This unique challenge might underlie the high incidence of thrombocytopenia among preterm neonates. In this study, neonatal platelet production and turnover were investigated in newborn mice. Based on a combination of blood volume expansion and increasing platelet counts, the platelet mass increased sevenfold during the first 2 weeks of murine life, a time during which thrombopoiesis shifted from liver to bone marrow. Studies applying in vivo biotinylation and mathematical modeling showed that newborn and adult mice had similar platelet production rates, but neonatal platelets survived 1 day longer in circulation. This prolonged lifespan fully accounted for the rise in platelet counts observed during the second week of murine postnatal life. A study of pro-apoptotic and anti-apoptotic Bcl-2 family proteins showed that neonatal platelets had higher levels of the anti-apoptotic protein Bcl-2 and were more resistant to apoptosis induced by the Bcl-2/Bcl-xL inhibitor ABT-737 than adult platelets. However, genetic ablation or pharmacologic inhibition of Bcl-2 alone did not shorten neonatal platelet survival or reduce platelet counts in newborn mice, indicating the existence of redundant or alternative mechanisms mediating the prolonged lifespan of neonatal platelets. PMID:24599546

  16. Expansion of the neonatal platelet mass is achieved via an extension of platelet lifespan.

    PubMed

    Liu, Zhi-Jian; Hoffmeister, Karin M; Hu, Zhongbo; Mager, Donald E; Ait-Oudhia, Sihem; Debrincat, Marlyse A; Pleines, Irina; Josefsson, Emma C; Kile, Benjamin T; Italiano, Joseph; Ramsey, Haley; Grozovsky, Renata; Veng-Pedersen, Peter; Chavda, Chaitanya; Sola-Visner, Martha

    2014-05-29

    The fetal/neonatal hematopoietic system must generate enough blood cells to meet the demands of rapid growth. This unique challenge might underlie the high incidence of thrombocytopenia among preterm neonates. In this study, neonatal platelet production and turnover were investigated in newborn mice. Based on a combination of blood volume expansion and increasing platelet counts, the platelet mass increased sevenfold during the first 2 weeks of murine life, a time during which thrombopoiesis shifted from liver to bone marrow. Studies applying in vivo biotinylation and mathematical modeling showed that newborn and adult mice had similar platelet production rates, but neonatal platelets survived 1 day longer in circulation. This prolonged lifespan fully accounted for the rise in platelet counts observed during the second week of murine postnatal life. A study of pro-apoptotic and anti-apoptotic Bcl-2 family proteins showed that neonatal platelets had higher levels of the anti-apoptotic protein Bcl-2 and were more resistant to apoptosis induced by the Bcl-2/Bcl-xL inhibitor ABT-737 than adult platelets. However, genetic ablation or pharmacologic inhibition of Bcl-2 alone did not shorten neonatal platelet survival or reduce platelet counts in newborn mice, indicating the existence of redundant or alternative mechanisms mediating the prolonged lifespan of neonatal platelets. © 2014 by The American Society of Hematology.

  17. Mean platelet volume in acute rheumatic fever.

    PubMed

    Sert, Ahmet; Aypar, Ebru; Odabas, Dursun

    2013-01-01

    Acute rheumatic fever (ARF) is still an endemic disease, especially among school-aged children in developing countries. Mean platelet volume (MPV), which is commonly used as a measure of platelet size, indicates the rate of platelet production and platelet activation. We aimed to investigate MPV in children with ARF. The study population consisted of 40 children with ARF (32 patients with carditis and 8 patients without carditis) and 40 healthy control subjects. White blood cell (WBC) and platelet counts were significantly higher and MPV values were significantly lower in patients with ARF during the acute stage when compared to controls. Erythrocyte sedimentation rate (ESR) and C-reactive protein values significantly decreased in patients with ARF after the treatment when compared to baseline, whereas MPV values increased. MPV values were negatively correlated with ESR and WBC, and platelet counts. In conclusion, during the acute stage of ARF, MPV values were lower when compared to controls.

  18. Therapeutic platelet reduction: Use in postsplenectomy thrombocytosis

    PubMed Central

    Negi, Gita; Talekar, Manjubala S.; Verma, Sanjiv Kumar; Rehmani, Babar; Gupta, Vibha; Agarwal, Amit; Harsh, Meena

    2015-01-01

    Therapeutic platelet reduction is an effective modality for the reduction of platelet count in patients with treatment of extreme thrombocytosis resulting from a variety of primary and secondary causes of thrombocytosis, which may be associated with thrombotic or hemorrhagic complications of varying degrees. These cases when symptomatic fall into the ASFA Category II indication for therapeutic platelet apheresis procedure. Here, we report a case of postsplenectomy secondary thrombocytosis presenting with extremely high platelet counts and subsequent thrombosis in the shunt and successful treatment after therapeutic platelet reduction. The case is being presented to bring forth the fact that therapeutic platelet reduction is an easy procedure that gives quick and good results and also to bring to the attention of transfusion specialists an associated but as yet unreported procedural finding. PMID:25722581

  19. The international experience of bacterial screen testing of platelet components with an automated microbial detection system: a need for consensus testing and reporting guidelines.

    PubMed

    Benjamin, Richard J; McDonald, Carl P

    2014-04-01

    The BacT/ALERT microbial detection system (bioMerieux, Inc, Durham, NC) is in routine use in many blood centers as a prerelease test for platelet collections. Published reports document wide variation in practices and outcomes. A systematic review of the English literature was performed to describe publications assessing the use of the BacT/ALERT culture system on platelet collections as a routine screen test of more than 10000 platelet components. Sixteen publications report the use of confirmatory testing to substantiate initial positive culture results but use varying nomenclature to classify the results. Preanalytical and analytical variables that may affect the outcomes differ widely between centers. Incomplete description of protocol details complicates comparison between sites. Initial positive culture results range from 539 to 10606 per million (0.054%-1.061%) and confirmed positive from 127 to 1035 per million (0.013%-0.104%) donations. False-negative results determined by outdate culture range from 662 to 2173 per million (0.066%-0.217%) and by septic reactions from 0 to 66 per million (0%-0.007%) collections. Current culture protocols represent pragmatic compromises between optimizing analytical sensitivity and ensuring the timely availability of platelets for clinical needs. Insights into the effect of protocol variations on outcomes are generally restricted to individual sites that implement limited changes to their protocols over time. Platelet manufacturers should reassess the adequacy of their BacT/ALERT screening protocols in light of the growing international experience and provide detailed documentation of all variables that may affect culture outcomes when reporting results. We propose a framework for a standardized nomenclature for reporting of the results of BacT/ALERT screening. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Platelet monoamine oxidase in early childhood autism.

    PubMed

    Cohen, D J; Young, J G; Roth, J A

    1977-05-01

    Platelet monoamine oxidase (MAO) activity was studied in 31 individuals suffering from early childhood autism and was not significantly different from that found in normal children or adults. In the autistic children, MAO activity decreased with age, and there was a trend toward greater platelet MAO activity in prepubertal and pubertal male autistic children relative to normal male children. Total platelet counts were not elevated in autistic children.

  1. Carbohydrate counting with an automated bolus calculator helps to improve glycaemic control in children with type 1 diabetes using multiple daily injection therapy: an 18-month observational study.

    PubMed

    Rabbone, Ivana; Scaramuzza, Andrea E; Ignaccolo, Maria Giovanna; Tinti, Davide; Sicignano, Sabrina; Redaelli, Francesca; De Angelis, Laura; Bosetti, Alessandra; Zuccotti, Gian Vincenzo; Cerutti, Franco

    2014-03-01

    This study aimed to investigate the effect of carbohydrate counting (carbC), with or without an automated bolus calculator (ABC), in children with type 1 diabetes treated with multiple daily insulin injections. We evaluated 85 children, aged 9-16 years, with type 1 diabetes, divided into four groups: controls (n=23), experienced carbC (n=19), experienced carbC+ABC (n=18) and non-experienced carbC+ABC (n=25). Glycated haemoglobin (HbA1c), insulin use, and glycaemic variability - evaluated as high blood glucose index (HBGI) and low blood glucose index (LBGI) - were assessed at baseline and after 6 and 18 months. At baseline, age, disease duration, BMI, HbA1c, insulin use, and HBGI (but not LBGI; p=0.020) were similar for all groups. After 6 months, HbA1c improved from baseline, although not significantly - patients using ABC (according to manufacturer's recommendations) HbA1c 7.14 ± 0.41% at 6 months vs. 7.35 ± 0.53% at baseline, (p=0.136) or without carbC experience HbA1c 7.61±0.62% vs. 7.95 ± 0.99% (p=0.063). Patients using ABC had a better HBGI (p=0.001) and a slightly worse LBGI (p=0.010) than those not using ABC. ABC settings were then personalised. At 18 months, further improvements in HbA1c were seen in children using the ABC, especially in the non-experienced carbC group (-0.42% from baseline; p=0.018). CarbC helped to improve glycaemic control in children with type 1 diabetes using multiple daily injections. ABC use led to greater improvements in HbA1c, HBGI and LBGI compared with patients using only carbC, regardless of experience with carbC. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Platelet activation of platelet concentrates derived from buffy coat and apheresis methods.

    PubMed

    Ali, Soleimany Ferizhandy

    2011-02-01

    Preparation for storage may cause platelet activation. The quality of platelet concentrates plays an important role in transfusion therapy. Platelet concentrates are produced by different centrifugation methods; buffy coat (buffy coat-derived platelet concentrates-BC) and plateletpheresis (apheresis-derived platelet concentrates-APC). Their quality was assessed using the following parameters: platelet, WBC and RBC counts pH, volume, platelet factor 4 (PF4) and Annexin V. The present paper compares the quality of both platelet preparations in vitro. In this experimental study, 30 platelet concentrates were harvested with the Haemonetics MCS plus and 30 units via the buffy coat (BC) method. The percentages of Annexin V expression, PF4 levels, platelet, WBC and RBC counts, pH and volume were measure immediately after collection and after 3 days of storage. During storage for up to 3 days, BC units displayed, no significant pH or RBC, difference in comparison with apheresis preparations (p>0.05). During storage for up to 3 days, BC units displayed a significant increase in the PF4 and Annexin V expression, compared to the apheresis preparations on day three (p<0.05). The kinetics of PF4 and Annexin V levels are influenced by the method used to prepare platelets for storage. The different levels of PF4 and Annexin V in BCs and APCs clearly demonstrates a progressive activation of BC platelets exceeding that of APC. However, in vivo studies should be performed to confirm these findings.

  3. Mean platelet volume in patients with fibromyalgia.

    PubMed

    Haliloğlu, S; Carlioglu, A; Sahiner, E; Karaaslan, Y; Kosar, A

    2014-10-01

    Fibromyalgia is a syndrome characterised by chronic widespread pain at multiple tender points, as well as joint stiffness and systemic symptoms. The aetiology and pathogenesis of fibromyalgia still remain unclear, although many contributory factors have been suggested. The presence of some common features between fibromyalgia and cardiovascular risk factors (e.g. depression and sleep disturbance) led to question of whether there is there a relationship between fibromyalgia and cardiovascular disease and/or atherosclerosis. Mean platelet volume, which is a determinant of platelet activation, is a newly emerging independent risk factor for cardiovascular disease.The present study was designed to evaluate levels of mean platelet volume in patients with fibromyalgia; the study population consisted of 283 individuals with this syndrome, who were compared with 72 healthy controls. Erythrocyte sedimentation rate, C-reactive protein, white blood cell count, platelet count and mean platelet volume levels were retrospectively recorded via the computerised patient database. The levels of mean platelet volume were significantly higher in the fibromyalgia group than in the control group (8.09 ± 0.84 fl and 7.73 ± 0.65 fl, respectively, p < 0.001). There were no statistical differences between groups with regard to platelet count and other parameters. These results suggest that an early atherosclerosis marker, mean platelet volume, is elevated in patients with fibromyalgia. This indicates increased platelet activation and therefore a higher risk of future cardiovascular disease.

  4. Evaluation of the immature platelet fraction in the diagnosis and prognosis of childhood immune thrombocytopenia.

    PubMed

    Adly, Amira Abdel Moneam; Ragab, Iman Ahmed; Ismail, Eman Abdel Rahman; Farahat, Mona Mohammed

    2015-01-01

    Rapid assessment of platelet production would distinguish between thrombocytopenia due to decreased platelet production or increased peripheral platelet destruction. We evaluated the value of immature platelet fraction (IPF) in differentiating immune thrombocytopenia (ITP) from thrombocytopenia secondary to bone marrow failure and its potential use as a prognostic marker. Forty-one young patients with ITP were compared with 14 patients with hematological malignancies under chemotherapy, representing a control group with thrombocytopenia due to bone marrow suppression and 30 age- and sex-matched healthy controls. Patients were studied stressing on bleeding manifestations, organomegaly/lymphadenopathy and therapy. Complete blood count including IPF was performed using Sysmex XE-2100. ITP patients were classified into two subgroups: acute ITP with spontaneous resolution within 3 months from diagnosis and chronic ITP that lasted ≥ 1 year from diagnosis. Median IPF was 11.8% in patients with ITP, 7% in those with hematological malignancy and 3% in the control group (p < 0.001). ITP patients had significantly higher mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR) and IPF compared with patients with malignancy or healthy controls, while plateletcrit (PCT) was significantly lower in ITP patients than other groups (p < 0.001). IPF was increased in patients with chronic ITP compared with acute ITP group (p < 0.001). Patients with active ITP had the highest IPF followed by those in partial remission, while ITP patients in remission had the lowest IPF. IPF was positively correlated to the number of lines of treatment used, MPV, PDW and P-LCR, while negatively correlated to platelet count and PCT among ITP patients (p < 0.001). Multiple regression analysis showed that platelet count and P-LCR were independently related to IPF. ROC curve analysis revealed that the cut-off value of IPF at 9.4% could be diagnostic for ITP patients

  5. Platelet fibrinogen

    PubMed Central

    Castaldi, P. A.; Caen, J.

    1965-01-01

    Platelet fibrinogen has been studied in normal, thrombasthenic, and hypofibrinogenaemic subjects. It has been differentiated into adsorbed (plasma) and extractable (intraplatelet) fractions. Isotopic studies suggest that exchange does not occur between intraplatelet and plasma fibrinogen and it appears possible that the intra-platelet fraction may be derived from the megakaryocyte. Six of nine thrombasthenic patients were found to have a severe deficiency of both adsorbed and extractable fibrinogen. Since the remaining three had near-normal platelet fibrinogen and all nine failed to aggregate it is improbable that the failure to adsorb fibrinogen is responsible for the defect in aggregation. Magnesium partially corrects adhesion to fibrin and clot retraction by these platelets, but has not been found to influence their fibrinogen adsorption. It is considered that the basic platelet surface defect, of varying severity, is responsible for the abnormalities of adsorption, aggregation, and adhesion in thrombasthenia. In the case of congenital hypofibrinogenaemia, fibrinogen transfusion corrects the long bleeding time, platelet-adsorbed fibrinogen, and the ability of platelets to spread on glass. It is possible that fibrinogen influences the surface properties of human platelets, although the final mechanism is not determined. Images PMID:5835438

  6. Evaluation of hematological values obtained with reference automated hematology analyzers of six manufacturers.

    PubMed

    Takubo, Takayuki; Tatsumi, Noriyuki; Satoh, Naotake; Matsuno, Kazuhiko; Fujimoto, Keiji; Soga, Masahiko; Yamagami, Yoshinori; Akiba, Shunichi; Sudoh, Tohru; Miyazaki, Makoto

    2002-01-01

    We evaluated assays of the same fresh blood samples with six different types of reference automated hematology analyzers developed by the following manufacturers: Beckman Coulter, Sysmex, Bayer, Abbott, Nihon Kohden and Horiba. Fresh whole blood samples treated with dipotassium ethylenediaminetetraacetic acid (EDTA K2) were collected from three healthy adult volunteers. The complete blood counts (CBC) including red blood cell count (RBC), hemoglobin (Hgb), hematocrit (Hct), mean corpuscular volume (MCV), white blood cell count (WBC), platelet count (Plt), reticulocyte percentage (Ret) and leukocyte differential counts including % neutrophils (Neu), % lymphocytes (Lym) and % monocytes (Mon) were surveyed with a reference automated hematology analyzer from each manufacturer. The process from sampling to analysis was performed according to procedures in hospital clinical laboratories. RBC, Hgb, Hct and MCV exhibited allowable differences within 5% of mean value among all instruments. Large differences greater than 10% of mean value in WBC, Neu and Lym between Horiba and other manufacturers, and in Plt between Nihon Kohden and other manufacturers, were observed. Ret and Mon exhibited large differences over 10% of mean value among almost all of the instruments tested. This survey suggests that all parameters exhibiting differences greater than 10% of mean value among instruments should be improved for clinical use to ensure good external quality control in blood cell counting and leukocyte differential counting using automated instruments.

  7. Decreased TGF-β1 and VEGF Release in Cystic Fibrosis Platelets: Further Evidence for Platelet Defects in Cystic Fibrosis

    PubMed Central

    Maloney, James P.; Narasimhan, Jayashree; Biller, Julie

    2016-01-01

    Purpose Cystic fibrosis (CF) patients suffer from chronic lung inflammation. This inflammation may activate platelets. There are limited data on the role of platelet-secreted cytokines in CF. Platelet cytokines with inflammatory effects include vascular endothelial growth factor (VEGF) and transforming growth factor-β1 (TGF-β1). As levels of these cytokines are tenfold greater in serum than plasma due to platelet release, serum levels may be one index of platelet content; but a more specific index is release during the aggregation of isolated platelets. We postulated that altered release of these platelet cytokines occurs in CF. Methods We obtained sera and plasma from CF outpatients (n=21) and from healthy controls (n=20), measured VEGF and TGF-β1, assessed for correlations with platelet number, analyzed cytokine release during platelet aggregation to collagen, and analyzed differences in maximal platelet aggregation. Results Platelet number and maximal aggregation levels were higher in CF. Plasma and serum levels of TGF-β1 and VEGF were higher in CF, but these levels were similar after adjusting for platelet number (serum cytokines correlated with platelet count). The release of VEGF and TGF-β1 during aggregation was decreased in CF platelets (by 52% and 29%, respectively). Conclusion Platelet release is not a source of the elevated blood proinflammatory cytokines TGF-β1 and VEGF in CF, as platelets from CF patients actually release less of these cytokines. These data provide further evidence for platelet defects in CF. PMID:27423781

  8. Platelet and red blood cell indices in Harris platelet syndrome.

    PubMed

    Naina, Harris V K; Harris, Samar

    2010-01-01

    Inherited thrombocytopenias, including inherited giant platelet disorders (IGPD) or macro thrombocytopenias are relatively rare, but their prevalence is likely underestimated from complexities of diagnosis and a spectrum of subclinical phenotypes. Harris platelet syndrome (HPS) is the most common IGPD reported from the Indian subcontinent. Of note there are an increased number of hemoglobinopathies reported from the geographic location. We analysed red blood cell and platelet indices of blood donors with HPS from the north eastern part of India and compared them with blood indices of blood donors of south India. We found a statistically significant lower platelet count in blood donors with HPS (median, range) 132 (71-267) vs. 252 (160-478) as compared to donors from south India (P < 0.001). Mean platelet volume (MPV) was higher in donors with HPS 13.1, (range 12-21.9 fl) as compared to donors from south India 7.35 (range 6-9.2 fl) (P < 0.001). This study showed that blood donors with HPS had a low median platelet bio-mass 0.17 (0.10-0.38%) vs. 0.19 (0.13-0.28%) in donors from south India. The platelet distribution width (PDW) was 17.4 (14.9-19.6) in donors with HPS vs. 16.38 (15.2-18.5) in south Indian blood donors (P < 0.001). Thirty-three donors with HPS had a normal platelet count with MPV more than 12 fL. Only donors with HPS had giant platelets and thrombocytopenia on peripheral blood smear examination. None of these donors had Dohle body inclusion in their leukocytes. Compared to donors from south India, donors with HPS had a significantly lower hemoglobin 13.8 (12-16.3 gm/dL) vs. 14.8 (12-18) respectively (P < 0.001) while red distribution width (RDW) was higher in HPS 13.6 (11.5-16.7) vs. 12.8 (11.4-15.1). However we did not find any statistically significant difference in MCV, MCH, MCHC between the two groups. Peripheral blood smear did not show any obvious abnormal red blood cell morphology. In the blood donors with HPS we found a statistically higher MPV

  9. A multicenter study evaluating three methods for counting residual WBCs in WBC-reduced blood components: Nageotte hemocytometry, flow cytometry, and microfluorometry.

    PubMed

    Dzik, S; Moroff, G; Dumont, L

    2000-05-01

    A multicenter study was conducted to evaluate the performance characteristics of flow cytometry and microfluorimetry for counting low concentrations of WBCs and to compare the results with Nageotte hemocytometry. A two-phase study involving 10 centers located in the United States and in Europe was performed. Coded samples of RBCs and platelets were distributed by 24-hour (Phase 1) or 2-day (Phase 2) courier service to each test site for analysis. Samples were prepared to include concentrations of WBCs slightly above and below the concentration corresponding to the threshold standards for WBC-reduced RBCs and platelets. All centers tested samples by Nageotte hemocytometry plus one or both of two automated methods. Both flow cytometry and microfluorometry gave better results than Nageotte hemocytometry in testing freshly prepared samples. At WBC concentrations >5 per microL (RBCs) or >3 per microL (platelets), the intersite CV was <20 percent for the automated methods but >30 percent for the Nageotte hemocytometer method (p<0.001). Accuracy was greater for the automated methods than for the Nageotte hemocytometer method (p<0. 001). Nageotte hemocytometry showed a bias to underestimation relative to the results obtained with the automated methods. All methods had poorer performance in testing samples that required > or =2 days' shipment than in testing of those requiring overnight shipment. Automated methods for counting residual donor WBCs in WBC-reduced cellular components offer advantages of improved precision and greater accuracy than are seen with the Nageotte hemocytometer method. Automated methods are less labor-intensive but more costly than microscopic methods. Preparation and shipping methods will need further refinement for samples to be counted more than 24 hours after sample collection.

  10. Platelet function and constituents of platelet rich plasma.

    PubMed

    Pelletier, M H; Malhotra, A; Brighton, T; Walsh, W R; Lindeman, R

    2013-01-01

    Platelet Rich Plasma (PRP) therapies require blood to be processed prior to application, however, the full assessment of the output of platelet sequestration devices is lacking. In this study the products of the Autologous Fluid Concentrator (Circle BiologicsTM, Minneapolis, MN) and the Gravitational Platelet Separation System (GPS, Biomet, Warsaw, IN, USA) were evaluated in terms of platelet viability and PRP constituents. The AFC and GPS produced 6.4 (±1.0) ml and 6.3 (±0.4) ml of PRP, with platelet recovery of 46.4% (±14.7%) and 59.8% (±24.2%) producing fold increases of platelets of 4.19 (±1.62) and 5.19 (±1.62), respectively. Fibrinogen concentration was increased above baseline PPP produced with the AFC. pH was lower for both of the processed samples than for whole blood. White Blood Cell count was increased around 5 fold. Functional tests showed preserved viability with both devices. This represents essential knowledge that every treating physician should have before they can confidently administer PRP therapy produced by any method. These are the first published results of platelet function for the GPS system and the first performance results of the AFC system. The PRP produced is classified according to broad classifications as Leukocyte-PRP (L-PRP) for both devices.

  11. Platelet profile in patients with gestational diabetes: a retrospective study

    PubMed Central

    Sak, Muhammet Erdal; Soydinç, Hatice Ender; Özler, Ali; Evsen, Mehmet Sıddık; Turgut, Abdülkadir; Sak, Sibel; Gül, Talip

    2012-01-01

    Objective: To assess and compare alterations in the morphology and function of platelets occurring in gestational diabetes and healthy pregnancies. Material and Methods: A retrospective study was performed of 77 pregnant women: 42 cases with gestational diabetes and 35 healthy controls. The two groups were compared in terms of demographics and platelet parameters derived from complete blood counts. Results: The mean platelet volume (p=0.001) and HbA1c (p<0.001) were significantly increased in the patients with gestational diabetes. The mean platelet volume was well correlated with the platelet distribution width (rs=0.404, p<0.001) and the platelet count (rs=0.355, p=0.002) Conclusion: The mean platelet volume and other platelet parameters may significantly aid the identification of diabetic pregnants at risk for vascular complications. The role and possible clinical relevance of these changes during diabetic pregnancy need to be investigated in further studies. PMID:24592046

  12. Smart fast blood counting of trace volumes of body fluids from various mammalian species using a compact custom-built microscope cytometer (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Smith, Zachary J.; Gao, Tingjuan; Lin, Tzu-Yin; Carrade-Holt, Danielle; Lane, Stephen M.; Matthews, Dennis L.; Dwyre, Denis M.; Wachsmann-Hogiu, Sebastian

    2016-03-01

    Cell counting in human body fluids such as blood, urine, and CSF is a critical step in the diagnostic process for many diseases. Current automated methods for cell counting are based on flow cytometry systems. However, these automated methods are bulky, costly, require significant user expertise, and are not well suited to counting cells in fluids other than blood. Therefore, their use is limited to large central laboratories that process enough volume of blood to recoup the significant capital investment these instruments require. We present in this talk a combination of a (1) low-cost microscope system, (2) simple sample preparation method, and (3) fully automated analysis designed for providing cell counts in blood and body fluids. We show results on both humans and companion and farm animals, showing that accurate red cell, white cell, and platelet counts, as well as hemoglobin concentration, can be accurately obtained in blood, as well as a 3-part white cell differential in human samples. We can also accurately count red and white cells in body fluids with a limit of detection ~3 orders of magnitude smaller than current automated instruments. This method uses less than 1 microliter of blood, and less than 5 microliters of body fluids to make its measurements, making it highly compatible with finger-stick style collections, as well as appropriate for small animals such as laboratory mice where larger volume blood collections are dangerous to the animal's health.

  13. PLATELET FORMATION

    PubMed Central

    Thon, Jonathan N.; Italiano, Joseph E.

    2010-01-01

    Thrombocytopenia is the underlying cause of a number of major clinical conditions and genetic disorders worldwide. While therapeutic agents that bind and stimulate the thrombopoietin receptor are currently available, the development of drugs that directly stimulate megakaryocytes to generate platelets has lagged behind. To improve the management of thrombocytopenia, we will need to define the cell biological pathways that drive the production of platelets from megakaryocytes. This review integrates the latest research of platelet biogenesis and focuses on the molecular pathways that power and regulate proplatelet production. PMID:20620432

  14. Platelet activation determines the severity of thrombocytopenia in dengue infection

    PubMed Central

    Ojha, Amrita; Nandi, Dipika; Batra, Harish; Singhal, Rashi; Annarapu, Gowtham K.; Bhattacharyya, Sankar; Seth, Tulika; Dar, Lalit; Medigeshi, Guruprasad R.; Vrati, Sudhanshu; Vikram, Naval K.; Guchhait, Prasenjit

    2017-01-01

    Thrombocytopenia is common in patients with dengue virus (DENV) infections. With a focus on understanding the possible mechanism of thrombocytopenia in DENV infections we described a direct correlation between activation and depletion of platelets in patients. Our data showed a sharp decrease in platelet counts at day 4 of fever in patients. The high DENV genome copies in platelets correlated directly with the elevated platelet activation along with increased binding of complement factor C3 and IgG on their surface at day 4. Recovery in platelet count was observed on day 10 through day 6 and 8 with simultaneous decrease in platelet activation markers. Further, our in vitro data supported the above observations describing a concentration-dependent increase in platelet activation by DENV serotype-2. The high copy number of DENV2 genome in the platelet pellet correlated directly with platelet activation, microparticle generation and clot formation. Furthermore the DENV2-activated platelets were phagocytosed in large numbers by the monocytes. The DENV2-mediated lysis and clearance of platelets were abrogated in presence of platelet activation inhibitor, prostacyclin. These observations collectively suggest that platelet activation status is an important determinant of thrombocytopenia in dengue infections. A careful strategy of inactivation of platelets may rescue them from rapid destruction during DENV infections. PMID:28139770

  15. Status Report on Cryopreservation of Human Platelets.

    DTIC Science & Technology

    1979-03-27

    anticoagulated with 63 mlPost-Thaw Platelet Count X Volume of Thawed Platelets of CPD. The blood was centrifuged+ * at 4500 g for 2.5 minutes at 22 ± 2...C to isolate PRP , the PRP was centrifuged51-Chromium Platelet Survival In Vivo and then resuspended in 0.5 ml at 4500 g to concentrate the platelets...the fol- anticoagulated with 2.5 ml of 1.2% manually. The esuspended plateletminor modifications: EDTA in saline, were obtained I manate w suseled

  16. Platelet Cryopreservation Using Dimethyl Sulfoxide,

    DTIC Science & Technology

    plateletpheresis methods or cell separators. In recent studies, the corrected count increment following 66 transfusions of frozen platelets collected using the...Haemonetics Model 30 processor (Haemonetics Corp., Natick, Mass.) was 12,3000 (range 0-36,800) compared to a mean CCI of 11,7000 (0-34,900) using manual plateletpheresis technique (N = 211).

  17. Evidence of platelet activation in multiple sclerosis

    PubMed Central

    Sheremata, William A; Jy, Wenche; Horstman, Lawrence L; Ahn, Yeon S; Alexander, J Steven; Minagar, Alireza

    2008-01-01

    Objective A fatality in one multiple sclerosis (MS) patient due to acute idiopathic thrombocytopenic purpura (ITP) and a near fatality in another stimulated our interest in platelet function abnormalities in MS. Previously, we presented evidence of platelet activation in a small cohort of treatment-naive MS patients. Methods In this report, 92 normal controls and 33 stable, untreated MS patients were studied. Platelet counts, measures of platelet activation [plasma platelet microparticles (PMP), P-selectin expression (CD62p), circulating platelet microaggragtes (PAg)], as well as platelet-associated IgG/IgM, were carried out. In addition, plasma protein S activity was measured. Results Compared to controls, PMP were significantly elevated in MS (p < 0.001) and CD62p expression was also markedly elevated (p < 0.001). Both are markers of platelet activation. Platelet-associated IgM, but not IgG, was marginally elevated in MS (p = 0.01). Protein S in MS patients did not differ significantly from normal values. Conclusion Platelets are significantly activated in MS patients. The mechanisms underlying this activation and its significance to MS are unknown. Additional study of platelet activation and function in MS patients is warranted. PMID:18588683

  18. Platelet volume indices as predictive biomarkers for diabetic complications in Type 2 diabetic patients

    PubMed Central

    Buch, Archana; Kaur, Supreet; Nair, Rahul; Jain, Ambuj

    2017-01-01

    BACKGROUND: Platelet volume indices (PVI) such as mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large cell ratio (P-LCR) are the indicators of increased platelet activity and can be considered as potential biomarkers for diabetic complications. PURPOSE: To study PVI in Type 2 diabetics with and without complications in comparison to nondiabetic patients. MATERIALS AND METHODS: A case–control study was conducted on 300 Type 2 diabetics and 200 nondiabetics. Detailed clinical history regarding duration, hypertension, and complications was taken. PVI was obtained using automated cell counter. Fasting blood glucose, hemoglobin A1c, lipid profile, creatinine were also obtained. Diabetics were further categorized into patients with complications and without complications. Statistical analysis was performed by Statistical Package for the Social Sciences Version 17 (Chicago, IL) Student's t-test and ANOVA test. RESULTS: Platelet count was significantly decreased in diabetics (P = 0.005). MPV was significantly increased in diabetic patients with complications as compared to diabetics without complications and nondiabetic group (P < 0.0001). PDW showed statistically significant difference between diabetics with and without complications and nondiabetics (P < 0.0001). However, no statistically significant difference was observed in platelet-large cell ratio (P-LCR) among all the three study groups. We found statistically significant correlation of MPV with diabetic retinopathy (P = 0.000), nephropathy (P = 0.005), and diabetic foot (P = 0.048). PDW was significantly increased in diabetic retinopathy (P = 0.035) and nephropathy (P = 0.007). P-LCR had no statistically significant correlation with diabetic complications. CONCLUSION: MPV and PDW are predictive biomarkers of diabetic vascular complications. They are more significant in microvascular complications than macrovascular complications. PMID:28367021

  19. [Platelet-washing solution optimization].

    PubMed

    Grossin, E; Chamfly, V

    2005-10-01

    Different washing and homogénéisation solutions are hereby analysed by comparing the evolution of functional indicators during the preservation of washed aphaeresis platelet concentrates: physiological pH 4.5 and 6 solutions, buffered physiological pH 6.8 glucose solution, and two physiological pH 7 citrate solutions with acetate. Prior acidification of platelet concentrates proved to be essential. Two washings with manual or automated technique, guarantee residual proteins at a level of less than 0.5 g. Solutions T-Sol Baxter or SSP Macopharma allow us to obtain a product that meet the PSL specifications. Routine since June 2004, washings are done with a physiological pH 6 solution, then homogeneised with T-Sol solution. Platelet recovery, swirling phenomenon, lack of agrgegates, pH maintenance, low increase in the platelet average volume and maintenance of intra-cell potassium level, suggest that platelet entirety is preserved beyond the product's expiration date. The platelet transfusion yield of these products is satisfactory.

  20. Platelet Function Tests in Bleeding Disorders.

    PubMed

    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

  1. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  2. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  3. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  4. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  5. Comparison between the clinical efficacy of platelet concentrates, derived from buffy coat and apheresis in tumor patients.

    PubMed

    Hao, Baolan; Wang, Yan; Zhou, Jian; Shao, Shujun; Dong, Xiaofeng

    2017-08-01

    The aim of the present study was to evaluate the clinical efficacy between manual buffy coat-derived platelet concentrates (PCs) and automated apheresis platelet concentrates (APCs) in terms of their therapeutic effects. The corrected count increment (CCI) was calculated according to detected differences in platelet concentration in patients who underwent transfusion of APCs, prepared by an automated system (group I, 72 cases) or PCs derived from buffy coat by manual method (group II, 83 cases). The clinical efficacy was assessed in terms of the CCI and clinical symptoms. The platelet contents of all the PCs were detected before transfusion. The mean 1 h CCI was 13.56±4.45 and 24 h CCI was 8.67±4.21 in group I, while the mean 1 h CCI was 15.83±4.65 and 24 h CCI was 9.57±3.36 in group II. The effective rates judged by CCI for groups I and II were 53 and 64%, respectively, and those judged by clinical symptoms were 67 and 60%, respectively. In conclusion, the clinical effectiveness of manual PCs was similar to that for APCs; thus, it could be utilized for clinical use.

  6. WBC count

    MedlinePlus

    Leukocyte count; White blood cell count ... blood is 4,500 to 11,000 white blood cells per microliter (mcL) or 4.5 to 11. ... LOW WHITE BLOOD CELL (WBC) COUNT A low number of WBCs is called leukopenia. A WBC count below 4500 is below normal ...

  7. Detection of microbial contamination in platelets

    NASA Astrophysics Data System (ADS)

    Berg, Tracy L.; Leparc, German; Huffman, Debra E.; Gennaccaro, Angela L.; Garcia-Lopez, Alicia; Klungness, Greta; Stephans, Christie; Garcia-Rubio, Luis H.

    2005-03-01

    In the United States, approximately 100 patients develop fatal sepsis associated with platelet transfusions every year. Current culture methods take 24-48 hours to acquire results, which in turn decrease the shelf life of platelets. Many of the microorganisms that contaminate platelets can replicate easily at room temperature, which is the necessary storage temperature to keep platelets functional. Therefore, there is a need for in-situ quality control assessment of the platelet quality. For this purpose, a real time spectrophotometric technique has been developed. The Spectral Acquisition Processing Detection (SAPD) method, comprised of a UV-vis spectrophotometer and modeling algorithms, is a rapid method that can be performed prior to platelet transfusion to decrease the risk of bacterial infection to patients. The SAPD method has been used to determine changes in cell suspensions, based on size, shape, chemical composition and internal structure. Changes in these cell characteristics can in turn be used to determine microbial contamination, platelet aging and other physiologic changes. Detection limits of this method for platelet suspensions seeded with bacterial contaminants were identified to be less than 100 cfu/ml of sample. Bacterial counts below 1000 cfu/ml are not considered clinically significant. The SAPD method can provide real-time identification of bacterial contamination of platelets affording patients an increased level of safety without causing undue strain on laboratory budgets or personnel while increasing the time frame that platelets can be used by dramatically shortening contaminant detection time.

  8. A microfluidic biochip for complete blood cell counts at the point-of-care

    PubMed Central

    Hassan, U.; Reddy, B.; Damhorst, G.; Sonoiki, O.; Ghonge, T.; Yang, C.; Bashir, R.

    2016-01-01

    Complete blood cell counts (CBCs) are one of the most commonly ordered and informative blood tests in hospitals. The results from a CBC, which typically include white blood cell (WBC) counts with differentials, red blood cell (RBC) counts, platelet counts and hemoglobin measurements, can have implications for the diagnosis and screening of hundreds of diseases and treatments. Bulky and expensive hematology analyzers are currently used as a gold standard for acquiring CBCs. For nearly all CBCs performed today, the patient must travel to either a hospital with a large laboratory or to a centralized lab testing facility. There is a tremendous need for an automated, portable point-of-care blood cell counter that could yield results in a matter of minutes from a drop of blood without any trained professionals to operate the instrument. We have developed microfluidic biochips capable of a partial CBC using only a drop of whole blood. Total leukocyte and their 3-part differential count are obtained from 10 μL of blood after on-chip lysing of the RBCs and counting of the leukocytes electrically using microfabricated platinum electrodes. For RBCs and platelets, 1 μL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. We demonstrate a high correlation of blood cell counts compared to results acquired with a commercial hematology analyzer. This technology could potentially have tremendous applications in hospitals at the bedside, private clinics, retail clinics and the developing world. PMID:26909365

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

    PubMed Central

    Mokhtar, Munirah Binti; Hashim, Hasna Binti; Joshi, Sanmukh R

    2016-01-01

    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 109 /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. PMID:27011678

  10. Induction of platelet formation from megakaryocytoid cells by nitric oxide.

    PubMed

    Battinelli, E; Willoughby, S R; Foxall, T; Valeri, C R; Loscalzo, J

    2001-12-04

    Although the growth factors that regulate megakaryocytopoiesis are well known, the molecular determinants of platelet formation from mature megakaryocytes remain poorly understood. Morphological changes in megakaryocytes associated with platelet formation and removal of senescent megakaryocytes are suggestive of an apoptotic process. Previously, we have established that nitric oxide (NO) can induce apoptosis in megakaryocytoid cell lines. To determine whether there is an association between NO-induced apoptosis and platelet production, we exposed Meg-01 cells to S-nitrosoglutathione (GSNO) with or without thrombopoeitin (TPO) pretreatment and used flow cytometry and electron microscopy to assess platelet-sized particle formation. Meg-01 cells treated with TPO alone produced few platelet-sized particles (<3% of total counts), whereas treatment with GSNO alone produced a significant percentage of platelet-sized particles (22 +/- 4% of total counts); when combined with TPO pretreatment, however, GSNO led to a marked increase in platelet-sized particle production (48 +/- 3% of total counts). Electron microscopy confirmed that Meg-01 cells treated with TPO and GSNO yielded platelet-sized particles with morphological features specific for platelet forms. The platelet-sized particle population appears to be functional, because addition of calcium, fibrinogen, and thrombin receptor-activating peptide led to aggregation. These results demonstrate that NO facilitates platelet production, thereby establishing the essential role of NO in megakaryocyte development and thrombopoiesis.

  11. Single-step separation of platelets from whole blood coupled with digital quantification by interfacial platelet cytometry (iPC).

    PubMed

    Basabe-Desmonts, L; Ramstrom, S; Meade, G; O'Neill, S; Riaz, A; Lee, L P; Ricco, A J; Kenny, D

    2010-09-21

    We report the efficient single-step separation of individual platelets from unprocessed whole blood, enabling digital quantification of platelet function using interfacial platelet cytometry (iPC) on a chip. iPC is accomplished by the precision micropatterning of platelet-specific protein surfaces on solid substrates. By separating platelets from whole blood using specific binding to protein spots of a defined size, iPC implements a simple incubate-and-rinse approach, without sample preparation, that enables (1) the study of platelets in the physiological situation of interaction with a protein surface, (2) the choice of the number of platelets bound on each protein spot, from one to many, (3) control of the platelet-platelet distance, including the possibility to study noninteracting single platelets, (4) digital quantification (counting) of platelet adhesion to selected protein matrices, enabling statistical characterization of platelet subpopulations from meaningfully large numbers of single platelets, (5) the study of platelet receptor expression and spatial distribution, and (6) a detailed study of the morphology of isolated single platelets at activation levels that can be manipulated. To date, we have demonstrated 1-4 of the above list. Platelets were separated from whole blood using iPC with fibrinogen, von Willebrand factor (VWF), and anti-CD42b antibody printed "spots" ranging from a fraction of one to several platelet diameters (2-24 μm). The number of platelets captured per spot depends strongly on the protein matrix and the surface area of the spot, together with the platelet volume, morphology, and activation state. Blood samples from healthy donors, a May-Hegglin-anomaly patient, and a Glanzmann's Thrombasthenia patient were analyzed via iPC to confirm the specificity of the interaction between protein matrices and platelets. For example, the results indicate that platelets interact with fibrinogen spots only through the fibrinogen receptor (

  12. Platelet antibodies, activated platelets and serum leptin in childhood immune thrombocytopenic purpura.

    PubMed

    Badrawy, Hosny; Elsayh, Khalid I; Zahran, Asmaa M; El-Ghazali, Mohamad Hamdy

    2013-01-01

    The aim of this study was to evaluate the levels of platelet-associated antibodies (PAIgG and PAIgM), activated platelets and serum leptin in children with acute immune thrombocytopenic purpura (ITP). The study included 40 patients with ITP and 40 healthy age- and sex-matched controls. PAIgG, PAIgM and activated platelet levels were estimated by flow cytometry, and serum leptin levels were estimated by ELISA. Activated platelets and serum leptin were significantly higher in the ITP patients than in the controls. The percentage and mean fluorescence intensity of PAIgG and PAIgM staining were significantly higher in the patients than in the controls. Serum leptin and activated platelet levels in patients with thrombocytopenia of brief duration were significantly lower than those in patients with thrombocytopenia of prolonged duration. The levels of activated platelets, serum leptin and PAIgG were positively correlated, and the levels of serum leptin, activated platelets and platelet counts were negatively correlated. The increased levels of activated platelets, serum leptin and platelet-associated antibodies in children with acute ITP suggest that these factors could play a role in ITP pathogenesis. Additionally, activated platelets and serum leptin could have prognostic significance in paediatric acute ITP. Copyright © 2013 S. Karger AG, Basel.

  13. [Platelet allo-antibodies identification strategies for preventing and managing platelet refractoriness].

    PubMed

    Basire, A; Picard, C

    2014-11-01

    Platelet refractoriness is a serious complication for patients receiving recurrent platelet transfusions, which can be explained by non-immune and immune causes. Human Leukocyte Antigens (HLA) allo-immunization, especially against HLA class I, is the major cause for immune platelet refractoriness. To a lesser extent, allo-antibodies against specific Human Platelet Antigen (HPA) are also involved. Pregnancy, transplantation and previous transfusions can lead to allo-immune reaction against platelet antigens. After transfusion, platelet count is decreased by accelerated platelet destruction related to antibodies fixation on incompatible platelet antigens. New laboratory tests for allo-antibodies identification were developed to improve sensibility and specificity, especially with the LUMINEX(®) technology. The good use and interpretation of these antibodies assays can improve strategies for platelet refractoriness prevention and management with a patient adapted response. Compatible platelets units can be selected according to their identity with recipient typing or immune compatibility regarding HLA or HPA antibodies or HLA epitope compatibility. Prospective studies are needed to further confirm the clinical benefit of new allo-antibodies identification methods and consensus strategies for immune platelet refractoriness management.

  14. Importance of immature platelet fraction as predictor of immune thrombocytopenic purpura

    PubMed Central

    Naz, Arshi; Mukry, Samina Naz; Shaikh, Mahwish Rauf; Bukhari, Ali Raza; Shamsi, Tahir Sultan

    2016-01-01

    Background and Objective: Immune thrombocytopenic purpura (ITP) is a clinical syndrome in which a decreased number of circulating platelets (thrombocytopenia) manifests as a bleeding tendency, easy bruising (purpura) or extravasation of blood from capillaries into skin and mucous membranes (petechiae). The diagnosis of ITP can be made clinically on the basis of symptoms, we need to see if ITP can be confirmed in patients by quantification of residual RNA containing immature platelets (megakaryocytic mass) or immature platelets fraction (IPF) using automated hematology analyzers (Sysmex XE-2100). Methods: In order to check the efficacy of IPF% parameter of Sysmex XE-2100 a total of 231 patients of thrombocytopenia were included in this study. Complete blood count (CBC) was estimated. The data was statistically analyzed by SPSS version 17. Results: About 62 patients were diagnosed as ITP and 169 patients were diagnosed as non ITP on the basis of clinical history. The mean IPF % value of ITP patients was 16.39% and the IPF % value of Non ITP patients was ~7.69% respectively. There was no significant difference in IPF% values with respect to time between sampling and acquisition of complete blood count. The diagnostic sensitivity of IPF% as biomarker for ITP and non-ITP was 85.71% (95%CI: 84.04% to 85.96%) and 41.76% (95% CI: 39.87% to 43.65%). Conclusion: The mean IPF % value by Sysmex XE-2100 can be used to predict ITP. PMID:27375692

  15. Platelets contribute to growth and metastasis in hepatocellular carcinoma.

    PubMed

    Bihari, Chhagan; Rastogi, Archana; Shasthry, Saggere Muralikrishna; Bajpai, Meenu; Bhadoria, Ajeet Singh; Rajesh, S; Mukund, Amar; Kumar, Anupam; Sarin, Shiv K

    2016-09-01

    To determine the association of platelets with hepatocellular carcinoma (HCC) growth and its metastasis. We examined platelets, laboratory, and radiological data of consecutive 420 HCC and 1008 cirrhosis cases. Follow-up information of platelet count in cirrhosis to HCC, pre- to post-therapy, and post-therapy to HCC outcome was analyzed. Cytokine profiling was performed in HCC and cirrhosis (n = 10 each). On the basis of imaging, HCC was divided into six subgroups. Cytosmears of HCC were assessed for platelet clustering around tumor cells. An in vitro Matrigel invasion assay was performed on human HCC cell lines using graded concentration of platelets. Baseline platelet numbers and platelet/lymphocyte ratios (PLRs) were significantly higher (p < 0.001) in HCC than cirrhosis. IL-1, IL-6, FGF, G-CSF, thrombopoietin, and VEGF were higher in HCC than cirrhosis. Platelet counts were increased after HCC conversion of cirrhosis (p < 0.001) and decreased (p < 0.001) after therapy. Platelets and PLR in recurrence cases were higher than in responders at baseline. AFP, PIVKAII, platelets, and PLR increase (p < 0.001 each) with advancement in HCC growth. Multivariate analysis showed platelets (p = 0.002), PLR (p = 0.004), and AFP (p < 0.001) associated with distant metastasis. Platelet clustering seen in 75.7% of HCC group 3, 45% in group 2, and 12.5% in group 1 cases (p < 0.001). Invaded cells in Matrigel assay positively correlated with platelet concentration. Platelets can contribute to the development, growth, invasion, and metastasis of HCC. Rising platelet count after HCC therapy is indicative of incomplete response or recurrence.

  16. Fractal analysis of circulating platelets in type 2 diabetic patients.

    PubMed

    Bianciardi, G; Tanganelli, I

    2015-01-01

    This paper investigates the use of computerized fractal analysis for objective characterization by means of transmission electron microscopy of the complexity of circulating platelets collected from healthy individuals and from type 2 diabetic patients, a pathologic condition in which platelet hyperreactivity has been described. Platelet boundaries were extracted by means of automatically image analysis. Local fractal dimension by box counting (measure of geometric complexity) was automatically calculated. The results showed that the platelet boundary observed by electron microscopy is fractal and that the shape of the circulating platelets is significantly more complex in the diabetic patients in comparison to healthy subjects (p <  0.01), with 100% correct classification. In vitro activated platelets from healthy subjects show an analogous increase of geometric complexity. Computerized fractal analysis of platelet shape by transmission electron microscopy can provide accurate, quantitative, data to study platelet activation in diabetes mellitus.

  17. Assessment of platelet function in healthy sedated cats using three whole blood platelet function tests.

    PubMed

    Ho, Kimberly K; Abrams-Ogg, Anthony C G; Wood, R Darren; O'Sullivan, M Lynne; Kirby, Gordon M; Blois, Shauna L

    2015-05-01

    The objectives of this study were to establish feline references intervals for 3 commercial whole blood platelet function test analyzer systems: Multiplate analyzer (MP; Roche Diagnostics International Ltd., Rotkreuz, Switzerland), Platelet Function Analyzer-100 (PF: Siemens Canada, Mississauga, Ontario, Canada), and Plateletworks Combo-25 kit (PW; Helena Laboratories, Beaumont, TX). Venipuncture was performed on 55 healthy sedated cats, and platelet aggregation in response to adenosine diphosphate (ADP), collagen (COL), and arachidonic acid (AA; MP only) was assessed using citrated blood. For the MP analyzer, median (95% confidence intervals [CIs]) area under curve (Units) for ADP, COL, and AA agonists were 87 (11-176), 81 (32-129), and 91 (59-129), respectively. For the PF analyzer, median (95% CIs) closure time, using COL-ADP cartridges, was 69 (46-89) sec. For the PW assay, median (95% CIs) percent aggregations for ADP and COL agonists were 71 (18-92) and 49 (9-96), respectively, using impedance hematology analyzer platelet counts, and 94 (25-98) and 68 (14-119), respectively, using flow cytometry hematology analyzer platelet counts. There were low correlations between the PF analyzer (COL-ADP cartridge) and MP analyzer (COL agonist; ρ = 0.11), and between the PF analyzer (COL-ADP cartridge) and PW assay (COL agonist using impedance platelet counts; ρ = 0.14). The PW assay percent aggregations using impedance and flow cytometric platelet counts were correlated for both ADP (ρ = 0.64) and COL (ρ = 0.64) agonists. Platelet function testing using these tests are feasible in cats, but 95% CIs are wide, so single results may be difficult to interpret. Platelet counting by impedance or flow cytometry may be used for the PW assay but are not interchangeable.

  18. Identification of platelet refractoriness in oncohematologic patients

    PubMed Central

    Ferreira, Aline Aparecida; Zulli, Roberto; Soares, Sheila; de Castro, Vagner; Moraes-Souza, Helio

    2011-01-01

    OBJECTIVES: To identify the occurrence and the causes of platelet refractoriness in oncohematologic patients. INTRODUCTION: Platelet refractoriness (unsatisfactory post-transfusion platelet increment) is a severe problem that impairs the treatment of oncohematologic patients and is not routinely investigated in most Brazilian services. METHODS: Forty-four episodes of platelet concentrate transfusion were evaluated in 16 patients according to the following parameters: corrected count increment, clinical conditions and detection of anti-platelet antibodies by the platelet immunofluorescence test (PIFT) and panel reactive antibodies against human leukocyte antigen class I (PRA-HLA). RESULTS: Of the 16 patients evaluated (median age: 53 years), nine (56%) were women, seven of them with a history of pregnancy. An unsatisfactory increment was observed in 43% of the transfusion events, being more frequent in transfusions of random platelet concentrates (54%). Platelet refractoriness was confirmed in three patients (19%), who presented immunologic and non-immunologic causes. Alloantibodies were identified in eight patients (50%) by the PIFT and in three (19%) by the PRA-HLA. Among alloimmunized patients, nine (64%) had a history of transfusion, and three as a result of pregnancy (43%). Of the former, two were refractory (29%). No significant differences were observed, probably as a result of the small sample size. CONCLUSION: The high rate of unsatisfactory platelet increment, refractoriness and alloimmunization observed support the need to set up protocols for the investigation of this complication in all chronically transfused patients, a fundamental requirement for the guarantee of adequate management. PMID:21437433

  19. CCL5 derived from platelets increases megakaryocyte proplatelet formation

    PubMed Central

    Machlus, Kellie R.; Johnson, Kelly E.; Kulenthirarajan, Rajesh; Forward, Jodi A.; Tippy, Mason D.; Soussou, Thomas S.; El-Husayni, Saleh H.; Wu, Stephen K.; Wang, Suming; Watnick, Randolph S.; Italiano, Joseph E.

    2016-01-01

    In times of physiological stress, platelet count can transiently rise. What initiates this reactive thrombocytosis is poorly understood. Intriguingly, we found that treating megakaryocytes (MKs) with the releasate from activated platelets increased proplatelet production by 47%. Platelets store inflammatory cytokines, including the chemokine ligand 5 (CCL5, RANTES); after TRAP activation, platelets release over 25 ng/mL CCL5. We hypothesized that CCL5 could regulate platelet production by binding to its receptor, CCR5, on MKs. Maraviroc (CCR5 antagonist) or CCL5 immunodepletion diminished 95% and 70% of the effect of platelet releasate, respectively, suggesting CCL5 derived from platelets is sufficient to drive increased platelet production through MK CCR5. MKs cultured with recombinant CCL5 increased proplatelet production by 50% and had significantly higher ploidy. Pretreating the MK cultures with maraviroc prior to exposure to CCL5 reversed the augmented proplatelet formation and ploidy, suggesting that CCL5 increases MK ploidy and proplatelet formation in a CCR5-dependent manner. Interrogation of the Akt signaling pathway suggested that CCL5/CCR5 may influence proplatelet production by suppressing apoptosis. In an in vivo murine acute colitis model, platelet count significantly correlated with inflammation whereas maraviroc treatment abolished this correlation. We propose that CCL5 signaling through CCR5 may increase platelet counts during physiological stress. PMID:26647394

  20. Increased platelet adhesion under flow conditions is induced by both thalassemic platelets and red blood cells.

    PubMed

    Goldschmidt, Neta; Spectre, Galia; Brill, Alexander; Zelig, Orly; Goldfarb, Ada; Rachmilewitz, Eliezer; Varon, David

    2008-11-01

    Thromboembolic complications are not uncommon in thalassemia. Previous studies suggest increased platelet aggregation and a potential role of pathological changes in the red blood cell (RBC) lipid membrane, induced by oxidative stress. In the present study, platelet adhesion and the effect of thalassemic RBC on platelet adhesion under flow conditions were evaluated, using the Cone and Plate (let) Analyzer(CPA). Twenty-two beta-thalassemia patients and 22 blood type-matched healthy controls were studied. An increased platelet adhesion (% surface coverage, SC), was observed in patients as compared to controls (p < 0.05). When platelet count and haematocrit were normalized by autologous reconstitution, a significant increase in platelet aggregation (average size, AS) was observed (p < 0.05). Increased platelet adhesion (SC and AS), was demonstrated in six patients with a history of thrombosis as compared to 16 patients without any history of thrombosis (p < or = 0.007) and in 17 splenectomized patients as compared to five non-splenectomized patients (p = 0.003). In reconstitution studies, thalassemic RBC mixed with normal platelet-rich plasma significantly increased platelet adhesion compared to normal RBC (SC p < 0.03, AS p < 0.02). Thalassemic platelets reconstituted with normal RBC, had increased aggregation (AS, p < 0.004) in comparison with normal platelets. The results indicate that increased platelet adhesion in beta-thalassemia is induced by both platelets and RBC. Increased platelet adhesion correlated with clinical thrombotic events and thus may suggest a mechanism of thrombosis in thalassemic patients. The potential application of the CPA in identifying thalassemic patients with high risk for thrombosis should be studied prospectively in a larger cohort of patients.

  1. Review of in vivo studies of dimethyl sulfoxide cryopreserved platelets.

    PubMed

    Slichter, Sherrill J; Jones, Melinh; Ransom, Janet; Gettinger, Irena; Jones, Mary Kay; Christoffel, Todd; Pellham, Esther; Bailey, S Lawrence; Corson, Jill; Bolgiano, Doug

    2014-10-01

    A literature review was conducted to assess the efficacy and safety of dimethyl sulfoxide (DMSO) cryopreserved platelets for potential military use. In vivo DMSO cryopreserved platelet studies published between 1972 and June of 2013 were reviewed. Assessed were the methods of cryopreservation, posttransfusion platelet responses, prevention or control of bleeding, and adverse events. Using the Department of Defense's preferred 6% DMSO cryopreservation method with centrifugation to remove the DMSO plasma before freezing at -65°C and no postthaw wash, mean radiolabeled platelet recoveries in 32 normal subjects were 33% ± 10% (52% ± 12% of the same subject's fresh platelet recoveries), and survivals were 7.5 ± 1.2 days (89% ± 15% of fresh platelet survivals). Using a variety of methods to freeze autologous platelets from 178 normal subjects, mean radiolabeled platelet recoveries were consistently 39% ± 9%, and survivals, 7.4 ± 1.4 days. More than 3000 cryopreserved platelet transfusions were given to 1334 patients. There were 19 hematology/oncology patient studies, and, in 9, mean 1-hour corrected count increments were 11 100 ± 3600 (range, 5700-15 800) after cryopreserved autologous platelet transfusions. In 5 studies, bleeding times improved after transfusion; in 3, there was either no improvement or a variable response. In 4 studies, there was immediate cessation of bleeding after transfusion; in 3 studies, patients being supported only with cryopreserved platelets had no bleeding. In 1 cardiopulmonary bypass study, cryopreserved platelets resulted in significantly less bleeding vs standard platelets. In 3 trauma studies, cryopreserved platelets were hemostatically effective. No significant adverse events were reported in any study. In summary, cryopreserved platelets have platelet recoveries that are about half of fresh platelets, but survivals are only minimally reduced. The platelets appear hemostatically effective and have no significant adverse events.

  2. Kinetics of indium-111-labelled platelets in HIV-infected patients with and without associated thrombocytopaenia.

    PubMed

    Van Wyk, V; Kotzé, H F; Heyns, A P

    1999-05-01

    Seven to 12% of HIV-infected patients have thrombocytopaenia. The pathophysiology of the thrombocytopaenia is not clear. It has been variously suggested that it may be caused by an increased peripheral platelet destruction, a defect in platelet production, or by a combination of these. The aim of the study was to elucidate the pathogenesis of HIV-associated thrombocytopaenia. We determined the mean platelet life span (MPLS) and calculated the turnover of autologous indium-111-labelled platelets in 17 HIV-positive patients, seven with thrombocytopaenia. The sites of sequestration of labelled platelets were quantified. The thrombocytopaenic patients had a very short MPLS (3.0+/-3.8 h) and a marked increase in platelet production (18.2+/-12.6x10(9)/l/h). The majority of these patients (5 of 7) had excessive sequestration of platelets in the spleen. Five of the patients with a normal blood platelet count had a shortened MPLS (109+/-23 h) and increased platelet turnover (3.8+/-1.2x10(9)/l/h), i.e. the increased peripheral platelet destruction was compensated for by increased platelet production. The other five patients with a normal platelet count had normal MPLS (195+/-11 h) and slightly increased platelet production (2.5+/-0.6x10(9)/l/h). We conclude that patients with HIV-associated thrombocytopaenia have increased peripheral platelet destruction. Platelet production is elevated but is insufficient to maintain a normal peripheral platelet count. In these patients platelets are predominantly sequestrated in the spleen. Patients with HIV infection and a normal blood platelet count may also have increased platelet production. This may be an early subclinical phase in the development of full-blown HIV-associated thrombocytopaenia.

  3. The quantitative and qualitative responses of platelets in pediatric patients undergoing cardiopulmonary bypass surgery.

    PubMed

    Ignjatovic, Vera; Than, Jenny; Summerhayes, Robyn; Newall, Fiona; Horton, Steve; Cochrane, Andrew; Monagle, Paul

    2012-01-01

    This prospective, single-center study aimed to evaluate the platelet response during cardiopulmonary bypass (CPB) surgery in a large cohort of children up to 6 years of age. Blood samples were drawn at four time points: after induction of anesthesia, after initiation of the CPB, before protamine, and immediately after chest closure. The study recruited 60 children requiring CPB for surgical repair of congenital heart defects. The platelet count decreased throughout CPB surgery, but during the same period, platelet activity increased. The more pronounced decrease in platelet count observed in children younger than 1 year compared with that of children 1 to 6 years of age was not associated with an age-specific change in platelet activity. The overall increase in platelet function observed in this study could provide a mechanism that compensates for the decrease in platelet count. This study provides a new foundation for future studies investigating requirements of platelet supplementation in the setting of pediatric CPB surgery.

  4. Single-step preparation and image-based counting of minute volumes of human blood.

    PubMed

    Smith, Zachary J; Gao, Tingjuan; Chu, Kaiqin; Lane, Stephen M; Matthews, Dennis L; Dwyre, Denis M; Hood, James; Tatsukawa, Keith; Heifetz, Laurence; Wachsmann-Hogiu, Sebastian

    2014-08-21

    Current flow-based blood counting devices require significant medical infrastructure and are not appropriate for field use. In this article we report on the development of a sample preparation, measurement, and analysis method that permits automated and accurate counting of red blood cells (RBCs), white blood cells (WBCs), and platelets, as well as allowing a 3-part differential of the WBCs to be performed on extremely small volumes of whole blood. This method is compatible with portable instrumentation that can be deployed in the field. The method consists of serially diluting blood samples first with sodium dodecyl sulfate dissolved in phosphate buffered saline, then in acridine orange dissolved in phosphate buffered saline, followed by fluorescence and dark field imaging with low magnification objectives. Image analysis is performed to extract cell counts and differentials. We performed a paired analysis of 20 volunteers with complete blood count values both within and beyond the normal reference range using a commercial automated hematology analyzer and the image-based method, with the new method achieving accuracies comparable to that of the commercial system. Because the sample preparation and imaging are simple and inexpensive to implement, this method has applications for pediatrics, clinician offices, and global health in regions that do not have access to central hematology laboratories.

  5. In vitro effect of sodium nitrite on platelet aggregation in human platelet rich plasma--preliminary report.

    PubMed

    Kadan, M; Doğanci, S; Yildirim, V; Özgür, G; Erol, G; Karabacak, K; Avcu, F

    2015-10-01

    The role of nitrates and nitric oxide on platelet functions has obtained an increasing attention with respect to their potential effects on cardiovascular disorders. In this study we aimed to analyze the effect of sodium nitrite on platelet functions in human platelets. This in vitro study was designed to show the effect of sodium nitrite on platelet functions in seven healthy volunteers. Blood samples were centrifuged to prepare platelet rich plasma and platelet poor plasma. Platelet rich plasma was diluted with the platelet poor plasma to have a final count of 300,000 ± 25,000 platelets. Platelet rich plasma was incubated with six different increasing doses (from 10 μM to 5 mM) of sodium nitrite for 1 hour at 37°C. Then stimulating agents including collagen (3 μg ml-1), adenosine diphosphate (10 μM), and epinephrine (10 μM) were added to the cuvette. Changes in light transmission were observed for 10 minutes. In addition spontaneous aggregation were performed in control group with all aggregating agents separately. Effect of sodium nitrite on agonist-induced platelet aggregation depends on the concentration of sodium nitrite. Compared with control group, agonist-induced platelet aggregations were significantly suppressed by sodium nitrite at the concentration of 5, 1.0 and 0.5 mM. Our results suggested that sodium nitrite has inhibitory effects in vitro on platelet aggregation in a dose-dependent manner.

  6. Characterization of enteric neurons in wild-type and mutant zebrafish using semi-automated cell counting and co-expression analysis.

    PubMed

    Simonson, Levi W; Ganz, Julia; Melancon, Ellie; Eisen, Judith S

    2013-06-01

    To characterize fluorescent enteric neurons labeled for expression of cytoplasmic markers in zebrafish mutants, we developed a new MATLAB-based program that can be trained by user input. We used the program to count enteric neurons and to analyze co-expression of the neuronal marker, Elavl, and the neuronal subtype marker, serotonin, in 3D confocal image stacks of dissected whole-mount zebrafish intestines. We quantified the entire population of enteric neurons and the serotonergic subpopulation in specific regions of the intestines of gutwrencher mutant and wild-type sibling larvae. We show a marked decrease in enteric neurons in gutwrencher mutants that is more severe at the caudal end of the intestine. We also show that gutwrencher mutants have the same number of serotonin-positive enteroendocrine cells in the intestine as wild types.

  7. Evaluation of an ethidium monoazide–enhanced 16S rDNA real-time polymerase chain reaction assay for bacterial screening of platelet concentrates and comparison with automated culture

    PubMed Central

    Garson, Jeremy A; Patel, Poorvi; McDonald, Carl; Ball, Joanne; Rosenberg, Gillian; Tettmar, Kate I; Brailsford, Susan R; Pitt, Tyrone; Tedder, Richard S

    2014-01-01

    BACKGROUND Culture-based systems are currently the preferred means for bacterial screening of platelet (PLT) concentrates. Alternative bacterial detection techniques based on nucleic acid amplification have also been developed but these have yet to be fully evaluated. In this study we evaluate a novel 16S rDNA polymerase chain reaction (PCR) assay and compare its performance with automated culture. STUDY DESIGN AND METHODS A total of 2050 time-expired, 176 fresh, and 400 initial-reactive PLT packs were tested by real-time PCR using broadly reactive 16S primers and a “universal” probe (TaqMan, Invitrogen). PLTs were also tested using a microbial detection system (BacT/ALERT, bioMérieux) under aerobic and anaerobic conditions. RESULTS Seven of 2050 (0.34%) time-expired PLTs were found repeat reactive by PCR on the initial nucleic acid extract but none of these was confirmed positive on testing frozen second aliquots. BacT/ALERT testing also failed to confirm any time-expired PLTs positive on repeat testing, although 0.24% were reactive on the first test. Three of the 400 “initial-reactive” PLT packs were found by both PCR and BacT/ALERT to be contaminated (Escherichia coli, Listeria monocytogenes, and Streptococcus vestibularis identified) and 14 additional packs were confirmed positive by BacT/ALERT only. In 13 of these cases the contaminating organisms were identified as anaerobic skin or oral commensals and the remaining pack was contaminated with Streptococcus pneumoniae. CONCLUSION These results demonstrate that the 16S PCR assay is less sensitive than BacT/ALERT and inappropriate for early testing of concentrates. However, rapid PCR assays such as this may be suitable for a strategy of late or prerelease testing. PMID:23701338

  8. Evaluation of an ethidium monoazide-enhanced 16S rDNA real-time polymerase chain reaction assay for bacterial screening of platelet concentrates and comparison with automated culture.

    PubMed

    Garson, Jeremy A; Patel, Poorvi; McDonald, Carl; Ball, Joanne; Rosenberg, Gillian; Tettmar, Kate I; Brailsford, Susan R; Pitt, Tyrone; Tedder, Richard S

    2014-03-01

    Culture-based systems are currently the preferred means for bacterial screening of platelet (PLT) concentrates. Alternative bacterial detection techniques based on nucleic acid amplification have also been developed but these have yet to be fully evaluated. In this study we evaluate a novel 16S rDNA polymerase chain reaction (PCR) assay and compare its performance with automated culture. A total of 2050 time-expired, 176 fresh, and 400 initial-reactive PLT packs were tested by real-time PCR using broadly reactive 16S primers and a "universal" probe (TaqMan, Invitrogen). PLTs were also tested using a microbial detection system (BacT/ALERT, bioMérieux) under aerobic and anaerobic conditions. Seven of 2050 (0.34%) time-expired PLTs were found repeat reactive by PCR on the initial nucleic acid extract but none of these was confirmed positive on testing frozen second aliquots. BacT/ALERT testing also failed to confirm any time-expired PLTs positive on repeat testing, although 0.24% were reactive on the first test. Three of the 400 "initial-reactive" PLT packs were found by both PCR and BacT/ALERT to be contaminated (Escherichia coli, Listeria monocytogenes, and Streptococcus vestibularis identified) and 14 additional packs were confirmed positive by BacT/ALERT only. In 13 of these cases the contaminating organisms were identified as anaerobic skin or oral commensals and the remaining pack was contaminated with Streptococcus pneumoniae. These results demonstrate that the 16S PCR assay is less sensitive than BacT/ALERT and inappropriate for early testing of concentrates. However, rapid PCR assays such as this may be suitable for a strategy of late or prerelease testing. © 2013 American Association of Blood Banks.

  9. Platelet associated antibodies

    MedlinePlus

    ... medlineplus.gov/ency/article/003552.htm Platelet-associated antibodies blood test To use the sharing features on ... JavaScript. This blood test shows if you have antibodies against platelets in your blood. Platelets are a ...

  10. Effects of alcohol ingestion post-exercise on platelet aggregation.

    PubMed

    El-Sayed, Mahmoud S

    2002-01-15

    The present study examined the influence of ingesting a moderate dose of alcohol on platelet count and platelet aggregation during recovery following exercise. Nineteen subjects (11 male and 8 female) were studied immediately after a standardised cycle ergometer test and during the 24-h period of recovery. In random order, alcohol (0.7 g/kg body mass) was given 1 h after exercise on one test occasion, while an equal volume of alcohol-free solution was administered on the other. Venous blood samples were obtained at baseline, post-exercise, and at 1, 5, and 22 h post-alcohol ingestion. Blood alcohol level increased significantly 1 h after the ingestion of alcohol, but decreased and returned to the resting baseline level at 5 h during recovery. Males and females subjects exhibited similar mean values of platelet count, platelet aggregation, and beta-thromboglobulin concentration at rest and following exercise and recovery. A significant increase in platelet count and a decrease in platelet aggregation using adenosine diphosphate (ADP) was found following exercise. Although plasma beta-thromboglobulin level (pooled data for males and females) showed an increase by 26.0% (from a mean pre-exercise value of 22.3-28.1 IU/ml), this rise was not significant (P>.05). The post-exercise increase in platelet count was mainly due to exercise-induced plasma volume loss. During recovery, while the increase in platelet count post-exercise returned to the baseline level in control and alcohol trials, the optical density of platelet aggregation remained significantly depressed at 5-h during recovery in the alcohol trial but not in the normal control condition. It is concluded that exercise induces significant reduction in platelet aggregation and the consumption of alcohol after physical exercise delays the normal return of platelet aggregation to the resting baseline levels during recovery.

  11. Platelets of the Wistar Furth rat have reduced levels of alpha-granule proteins. An animal model resembling gray platelet syndrome.

    PubMed Central

    Jackson, C W; Hutson, N K; Steward, S A; Saito, N; Cramer, E M

    1991-01-01

    Rats of the Wistar Furth (WF) strain have hereditary macrothrombocytopenia (large mean platelet volume [MPV] with increased platelet size heterogeneity and reduced platelet count). Ultrastructural studies suggest that this anomaly results from erratic subdivision of megakaryocyte cytoplasm into platelets. In this study, we have examined protein profiles of platelets of WF rats for biochemical abnormalities associated with this anomaly. Marked decreases in protein bands with an Mr of 185, 57, 53, 16, 13, and 8 kd were observed in one-dimensional reduced SDS-PAGE gels in WF platelets compared with platelets of Wistar, Long Evans, and Sprague-Dawley rats. These proteins were released into the supernatant when washed platelets were treated with thrombin suggesting that they were alpha-granule proteins. These abnormalities were not present in offspring of crosses between Wistar Furth and Wistar rats; however, they were present in platelets of offspring with large MPV derived from backcrosses of (WF X Wistar) F1 males to WF females, but not in backcross offspring with normal platelet size. Immunoblotting confirmed decreased levels of thrombospondin, fibrinogen, and platelet factor 4 in WF platelets. Electron microscopic examination revealed that platelet alpha granules were usually smaller in Wistar Furth than in Wistar rats. In addition, immunogold electron microscopy demonstrated that the surface connected canalicular system of the large Wistar Furth platelets, contained dense material composed of alpha-granule proteins, not present in Wistar platelets. From these results, we conclude that the Wistar Furth rat platelet phenotype of large mean platelet volume and decreased levels of alpha-granule proteins represents an animal model resembling gray platelet syndrome. The autosomal recessive pattern of inheritance of the large MPV phenotype and platelet alpha-granule protein deficiencies suggests that a component common to both formation of platelet alpha granules, and

  12. Daily prickly pear consumption improves platelet function.

    PubMed

    Wolfram, R; Budinsky, A; Efthimiou, Y; Stomatopoulos, J; Oguogho, A; Sinzinger, H

    2003-07-01

    Prickly pear is traditionally used by Pima Indians as a dietary nutrient against diabetes mellitus. We examined the effect of daily consumption of 250 g in 8 healthy volunteers and 8 patients with mild familial heterozygous hypercholesterolemia on various parameters of platelet function. Beside its action on lipids and lipoproteins, prickly pear consumption significantly reduced the platelet proteins (platelet factor 4 and beta-thromboglobulin), ADP-induced platelet aggregation and improved platelet sensitivity (against PGI2 and PGE1) in volunteers as well as in patients. Also plasma 11-DH-TXB2 and the WU-test showed a significant improvement in both patients and volunteers. In contrast, collagen-induced platelet aggregation and the number of circulating endothelial cells showed a significant response in patients only. No influence of prickly pear ingestion on peripheral platelet count was monitored. The dietary run-in period did not influence any of the parameters of haemostasis examined. No sex difference was seen. Prickly pear may induce at least part of its beneficial actions on the cardiovascular system via decreasing platelet activity and thereby improving haemostatic balance.

  13. Platelet function in the postprandial period

    PubMed Central

    2012-01-01

    Background Postprandial hyperlipidemia and hyperglycemia have been related to cardiovascular events. Among different underlying mechanisms platelet activation seems to be responsible too. No comparable data between various tests in normo- vs. hyperlipidemics before and at different time intervals are available after a fat meal. We aimed to compare 9 of them within the same patients at several time points in postprandial hyperlipidemia. Results For some tests baseline values between the groups were significantly different (TXB2, platelet sensitivity, sedimentation and WU-test). However, hyperlipidemia revealed a variable influence on the tests examined. Some of the available tests apparently sensitive to show platelet activation reflect the increase in triglycerides (TG), such as the sedimentation index. ADP-induced platelet aggregatory activity in count adjusted washed isolated platelet samples during postprandial hyperlipidemia indicates mildly enhanced platelet activity, but does not seem to induce significant changes in aggregation. In patients with severe hypertriglyceridemia (> 400 mg/dl fasting) changes in platelet function are more pronounced due to delayed decay and may last up to 16 hours paralleling TG reaching the prevalue. The overwhelming majority of platelet function tests do not significantly respond to postprandial hyperlipidemia. The correlation between the tests applied is poor. For standardization purpose, platelet aggregation tests, aimed to examine proaggregatory capacity in atherosclerosis, should only be performed at the same time of the day after a fasting period > 6 hours. The great variation in preanalytical work-up on comparison of various tests, large number of platelet tests available and their respective potential value are discussed. Conclusions At present, the suspicion that platelet function is significantly activated in the postprandial period cannot be supported by any of the tests used. The information provided is valuable to

  14. A Comparison of Mindray BC-6800, Sysmex XN-2000, and Beckman Coulter LH750 Automated Hematology Analyzers: A Pediatric Study.

    PubMed

    Ciepiela, Olga; Kotuła, Iwona; Kierat, Szymon; Sieczkowska, Sandra; Podsiadłowska, Anna; Jenczelewska, Anna; Księżarczyk, Karolina; Demkow, Urszula

    2016-11-01

    Modern automated laboratory hematology analyzers allow the measurement of over 30 different hematological parameters useful in the diagnostic and clinical interpretation of patient symptoms. They use different methods to measure the same parameters. Thus, a comparison of complete blood count made by Mindray BC-6800, Sysmex XN-2000 and Beckman Coulter LH750 was performed. A comparison of results obtained by automated analysis of 807 anticoagulated blood samples from children and 125 manual microscopic differentiations were performed. This comparative study included white blood cell count, red blood cell count, and erythrocyte indices, as well as platelet count. The present study showed a poor level of agreement between white blood cell enumeration and differentiation of the three automated hematology analyzers under comparison. A very good agreement was found when comparing manual blood smear and automated granulocytes, monocytes, and lymphocytes differentiation. Red blood cell evaluation showed better agreement than white blood cells between the studied analyzers. To conclude, studied instruments did not ensure satisfactory interchangeability and did not facilitate a substitution of one analyzer by another. © 2016 Wiley Periodicals, Inc.

  15. Tirofiban (Aggrastat) protects platelets and decreases platelet-granulocyte binding in an extracorporeal circulation model.

    PubMed

    Straub, A; Azevedo, R; Beierlein, W; Wendel, H P; Dietz, K; Ziemer, G

    2006-04-01

    Extracorporeal circulation (ECC) induces platelet activation and inflammation with potentially life-threatening organ dysfunction. Short-acting GP IIb/IIIa inhibitors like tirofiban and eptifibatide protect platelets during ECC without increasing bleeding complications and may reduce inflammation. This study investigates anti-thrombotic and anti-inflammatory effects of different platelet inhibitors. Control (untreated) and treated (using either 150 ng/mL tirofiban, 2.5 microg/mL eptifibatide, 0.7 microg/mL milrinone, 15 microg/mL dipyridamol, or 300 KIU/mL aprotinin) heparinized blood of healthy volunteers (n = 6) was recirculated in a well-established ECC model (Chandler loop). Percentage of platelet aggregates, P-selectin-expressing (activated) platelets, CD15-positive aggregates (indicating proinflammatory platelet-granulocyte binding), and platelet counts were determined before (baseline) and after 30 minutes recirculation in unstimulated and ADP-stimulated samples using flow cytometry. Statistical analysis was performed using multifactor ANOVA after transforming the data (logarithms for counts and log odds for percentages). Least square means were backtransformed to obtain appropriate means and their 95 % confidence intervals. Multiple post-hoc comparisons were performed by Tukey's HSD test with a global alpha of 5 %. Significant inhibition was observed for: 1) ECC-induced platelet aggregation by tirofiban (unstimulated: 2.2-fold/stimulated: 2.46-fold), eptifibatide (unstimulated: 1.96-fold/stimulated: 2.65-fold), and milrinone (unstimulated: 1.87-fold/stimulated: 1.37-fold); 2) ECC-induced P-selectin expression by tirofiban (unstimulated: 3.95-fold/stimulated: 2.54-fold), and eptifibatide (unstimulated: 5.87-fold/stimulated: 3.28-fold); 3) ECC-induced platelet loss by tirofiban (1.27-fold), and eptifibatide (1.25-fold); 4) ECC-induced platelet-granulocyte binding by tirofiban (unstimulated: 2.25-fold/stimulated: 1.59-fold), but not by eptifibatide. Amongst

  16. In vitro model of platelet aggregation in stenotic arteries

    SciTech Connect

    Morley, D.; Santamore, W.P.

    1988-07-01

    Clinical and experimental evidence suggest a strong relationship between arterial stenosis, platelet aggregation, and subsequent thrombus formation. To facilitate the study of platelet accumulation in stenotic arteries, we developed an in vitro preparation. Arterial segments were perfused with whole citrated blood. A stenosis was created by applying an external plastic constrictor to the artery. Platelet accumulation within the stenosis was assessed by scanning electron microscopy and by radioactive counts from Indium-111 labeled platelets. Utilizing this preparation, 30 carotid arterial segments from 10 mongrel dogs were perfused at 100 mmHg for 15 min. In 10 arteries without a stenosis, scanning electron microscopy and radioactive counts demonstrated little platelet accumulation. In contrast, extensive platelet aggregation was observed in 10 arteries with stenoses. Moreover, in 10 stenotic arteries exposed to the thromboxane mimetic, U46619 (Upjohn Diagnostic Group), scanning electron microscopy and radioactive counts demonstrated a significant increase in platelet deposition. Conversely, we demonstrated a dimunition of platelet accumulation in stenosed arterial segments exposed to the prostacyclin analogue platelet inhibitor, Iloprost. The in vitro preparation allows precise control of hemodynamic variables and makes it possible to perform multiple tests on segments of the same vessel from the same animal.

  17. Blood platelet kinetics and platelet transfusion.

    PubMed

    Aster, Richard H

    2013-11-01

    The discovery of citrate anticoagulant in the 1920s and the development of plastic packs for blood collection in the 1960s laid the groundwork for platelet transfusion therapy on a scale not previously possible. A major limitation, however, was the finding that platelet concentrates prepared from blood anticoagulated with citrate were unsuitable for transfusion because of platelet clumping. We found that this could be prevented by simply reducing the pH of platelet-rich plasma to about 6.5 prior to centrifugation. We used this approach to characterize platelet kinetics and sites of platelet sequestration in normal and pathologic states and to define the influence of variables such as anticoagulant and ABO incompatibility on post-transfusion platelet recovery. The "acidification" approach enabled much wider use of platelet transfusion therapy until alternative means of producing concentrates suitable for transfusion became available.

  18. Blood platelet kinetics and platelet transfusion

    PubMed Central

    Aster, Richard H.

    2013-01-01

    The discovery of citrate anticoagulant in the 1920s and the development of plastic packs for blood collection in the 1960s laid the groundwork for platelet transfusion therapy on a scale not previously possible. A major limitation, however, was the finding that platelet concentrates prepared from blood anticoagulated with citrate were unsuitable for transfusion because of platelet clumping. We found that this could be prevented by simply reducing the pH of platelet-rich plasma to about 6.5 prior to centrifugation. We used this approach to characterize platelet kinetics and sites of platelet sequestration in normal and pathologic states and to define the influence of variables such as anticoagulant and ABO incompatibility on post-transfusion platelet recovery. The “acidification” approach enabled much wider use of platelet transfusion therapy until alternative means of producing concentrates suitable for transfusion became available. PMID:24177466

  19. Maturation of Platelet Function During Murine Fetal Development In Vivo.

    PubMed

    Margraf, Andreas; Nussbaum, Claudia; Rohwedder, Ina; Klapproth, Sarah; Kurz, Angela R M; Florian, Annamaria; Wiebking, Volker; Pircher, Joachim; Pruenster, Monika; Immler, Roland; Dietzel, Steffen; Kremer, Ludmila; Kiefer, Friedemann; Moser, Markus; Flemmer, Andreas W; Quackenbush, Elizabeth; von Andrian, Ulrich H; Sperandio, Markus

    2017-06-01

    Platelet function has been intensively studied in the adult organism. However, little is known about the function and hemostatic capacity of platelets in the developing fetus as suitable in vivo models are lacking. To examine fetal platelet function in vivo, we generated a fetal thrombosis model and investigated light/dye-induced thrombus formation by intravital microscopy throughout gestation. We observed that significantly less and unstable thrombi were formed at embryonic day (E) 13.5 compared with E17.5. Flow cytometry revealed significantly lower platelet counts in E13.5 versus E17.5 fetuses versus adult controls. In addition, fetal platelets demonstrated changed activation responses of surface adhesion molecules and reduced P-selectin content and mobilization. Interestingly, we also measured reduced levels of the integrin-activating proteins Kindlin-3, Talin-1, and Rap1 during fetal development. Consistently, fetal platelets demonstrated diminished spreading capacity compared with adults. Transfusion of adult platelets into the fetal circulation led to rapid platelet aggregate formation even in young fetuses. Yet, retrospective data analysis of a neonatal cohort demonstrated no correlation of platelet transfusion with closure of a persistent ductus arteriosus, a process reported to be platelet dependent. Taken together, we demonstrate an ontogenetic regulation of platelet function in vivo with physiologically low platelet numbers and hyporeactivity early during fetal development shedding new light on hemostatic function during fetal life. © 2017 American Heart Association, Inc.

  20. Fractionation of platelets according to size: functional and biochemical characteristics.

    PubMed

    Carty, D J; Gear, A R

    1986-01-01

    The functional and biochemical heterogeneity of platelets has been studied using graded differential centrifugation to fractionate human platelets according to size while maintaining their morphological and functional integrity as indicated by scanning electron microscopy and content of beta-thromboglobulin. Aggregation kinetics were studied by both optical and quenched-flow methods involving single-particle counting. Large platelets were significantly more sensitive to ADP, but aggregated less rapidly than small platelets. Thrombin exerted a similar influence. Large platelets were also enriched in surface sialic acid and sulfhydryl groups and in internal glycogen, ATP, ADP, calcium, cyclic AMP, malonaldehyde, and succinate cytochrome c reductase when compared to small platelets, even when normalized per unit volume. ADP caused a more rapid breakdown of cyclic AMP in small platelets. Potential aging relationships were tested by isotope studies in rats. 75Se-selenomethionine was incorporated in vivo at a similar rate into all fractions. Large platelets labeled with 51Cr disappeared from circulation linearly and had a longer mean lifespan than small platelets, which disappeared exponentially. This behavior supports independent aging of platelet populations of differing size. The data suggest a distinct heterogeneity in platelet function and fate, which could derive from protection of large platelets against excessive activation by Ca2+-regulated events.

  1. Glutamate Receptor Interacting Protein 1 Mediates Platelet Adhesion and Thrombus Formation

    PubMed Central

    Modjeski, Kristina L.; Ture, Sara K.; Field, David J.; Cameron, Scott J.; Morrell, Craig N.

    2016-01-01

    Thrombosis-associated pathologies, such as myocardial infarction and stroke, are major causes of morbidity and mortality worldwide. Because platelets are necessary for hemostasis and thrombosis, platelet directed therapies must balance inhibiting platelet function with bleeding risk. Glutamate receptor interacting protein 1 (GRIP1) is a large scaffolding protein that localizes and organizes interacting proteins in other cells, such as neurons. We have investigated the role of GRIP1 in platelet function to determine its role as a molecular scaffold in thrombus formation. Platelet-specific GRIP1-/- mice were used to determine the role of GRIP1 in platelets. GRIP1-/- mice had normal platelet counts, but a prolonged bleeding time and delayed thrombus formation in a FeCl3-induced vessel injury model. In vitro stimulation of WT and GRIP1-/- platelets with multiple agonists showed no difference in platelet activation. However, in vivo platelet rolling velocity after endothelial stimulation was significantly greater in GRIP1-/- platelets compared to WT platelets, indicating a potential platelet adhesion defect. Mass spectrometry analysis of GRIP1 platelet immunoprecipitation revealed enrichment of GRIP1 binding to GPIb-IX complex proteins. Western blots confirmed the mass spectrometry findings that GRIP1 interacts with GPIbα, GPIbβ, and 14-3-3. Additionally, in resting GRIP1-/- platelets, GPIbα and 14-3-3 have increased interaction compared to WT platelets. GRIP1 interactions with the GPIb-IX binding complex are necessary for normal platelet adhesion to a stimulated endothelium. PMID:27631377

  2. Pseudothrombocytopenia due to Platelet Clumping: A Case Report and Brief Review of the Literature

    PubMed Central

    Tan, Geok Chin; Stalling, Melissa; Dennis, Gretchen; Nunez, Maria

    2016-01-01

    Platelet clumping is a common laboratory phenomenon that complicates or precludes reporting of platelet count. It is often, but not always, a phenomenon commonly caused by the anticoagulant EDTA. Herein, we discuss a case of a 14-year-old girl who was found to have platelet clumping and discuss the work-up she underwent to investigate her pseudothrombocytopenia. PMID:28044112

  3. Thrombocytopenia, bleeding, and use of platelet transfusions in sick neonates.

    PubMed

    Stanworth, Simon J

    2012-01-01

    Survival rates for infants born prematurely have improved significantly, in part due to better supportive care such as RBC transfusion. The role of platelet transfusions in neonates is more controversial. Neonatal thrombocytopenia is common in premature infants. The primary causal factors are intrauterine growth restriction/maternal hypertension, in which the infant presents with thrombocytopenia soon after birth, and sepsis/necrotizing enterocolitis, which are the common morbidities associated with thrombocytopenia in neonates > 72 hours of age. There is no evidence of a relationship between platelet count and occurrence of major hemorrhage, and cardiorespiratory problems are considered the main etiological factors in the development of intraventricular and periventricular hemorrhage in the neonatal period. Platelet transfusions are used commonly as prophylaxis in premature neonates with thrombocytopenia. However, there is widespread variation in the pretransfusion thresholds for platelet count and evidence of marked disparities in platelet transfusion practice between hospitals and countries. Platelet transfusions are biological agents and as such are associated with risks. Unlike other patient groups, specifically patients with hematological malignancies, there have been no recent clinical trials undertaken comparing different thresholds for platelet transfusion in premature neonates. Therefore, there is no evidence base with which to inform safe and effective practice for prophylactic platelet transfusions. There is a need for randomized controlled trials to define the optimal use of platelet transfusions in premature neonates, who at present are transfused heavily with platelets.

  4. Guidance on platelet transfusion for patients with hypoproliferative thrombocytopenia.

    PubMed

    Nahirniak, Susan; Slichter, Sherrill J; Tanael, Susano; Rebulla, Paolo; Pavenski, Katerina; Vassallo, Ralph; Fung, Mark; Duquesnoy, Rene; Saw, Chee-Loong; Stanworth, Simon; Tinmouth, Alan; Hume, Heather; Ponnampalam, Arjuna; Moltzan, Catherine; Berry, Brian; Shehata, Nadine

    2015-01-01

    Patients with hypoproliferative thrombocytopenia are at an increased risk for hemorrhage and alloimmunization to platelets. Updated guidance for optimizing platelet transfusion therapy is needed as data from recent pivotal trials have the potential to change practice. This guideline, developed by a large international panel using a systematic search strategy and standardized methods to develop recommendations, incorporates recent trials not available when previous guidelines were developed. We found that prophylactic platelet transfusion for platelet counts less than or equal to 10 × 10(9)/L is the optimal approach to decrease the risk of hemorrhage for patients requiring chemotherapy or undergoing allogeneic or autologous transplantation. A low dose of platelets (1.41 × 10(11)/m2) is hemostatically as effective as higher dose of platelets but requires more frequent platelet transfusions suggesting that low-dose platelets may be used in hospitalized patients. For outpatients, a median dose (2.4 × 10(11)/m2) may be more cost-effective to prevent clinic visits only to receive a transfusion. In terms of platelet products, whole blood-derived platelet concentrates can be used interchangeably with apheresis platelets, and ABO-compatible platelet should be given to improve platelet increments and decrease the rate of refractoriness to platelet transfusion. For RhD-negative female children or women of child-bearing potential who have received RhD-positive platelets, Rh immunoglobulin should probably be given to prevent immunization to the RhD antigen. Providing platelet support for the alloimmunized refractory patients with ABO-matched and HLA-selected or crossmatched products is of some benefit, yet the degree of benefit needs to be assessed in the era of leukoreduction.

  5. Multiplicity Counting

    SciTech Connect

    Geist, William H.

    2015-12-01

    This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pueff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

  6. Lymphocyte-platelet crosstalk in Graves' disease.

    PubMed

    Kuznik, Boris I; Vitkovsky, Yuri A; Gvozdeva, Olga V; Solpov, Alexey V; Magen, Eli

    2014-03-01

    Platelets can modulate lymphocytes' role in the pathophysiology of thyroid autoimmune diseases. The present study was performed to clarify the status of platelet-lymphocyte subpopulations aggregation in circulating blood in patients with Graves' disease (GD). One hundred and fifty patients with GD (GD group) and 45 hyperthyroid patients with toxic multinodular goiter (TMG group) were recruited in the study. Control group consisted 150 healthy subjects. Immunophenotyping of lymphocytes was performed by flow cytometry. Detection of lymphocyte-platelet aggregates (LPAs) was done using light microscope after Ficoll-gradient centrifugation. The group of GD patients exhibited reduced CD8 lymphocyte and higher CD19 cell counts compared with TMG group and healthy controls. A greater number of activated CD3, HLA-DR+ lymphocytes were observed in GD than in TMG group and control group. GD group was characterized by lower blood platelet count (232 ± 89 × 10 cells/µL) than TMG group (251 ± 97 × 10 cells/µL; P < 0.05) and control group (262 ± 95 × 10 cells/µL; P < 0.05). In GD group, more platelet-bound lymphocytes (332 ± 91 /µL) were found than that in TMG group (116 ± 67/µL, P < 0.005) and control group (104 ± 58 /µL; P < 0.001). GD is associated with higher levels of activated lymphocytes and lymphocyte-platelet aggregates.

  7. Effects of irradiation on platelet function

    SciTech Connect

    Rock, G.; Adams, G.A.; Labow, R.S.

    1988-09-01

    Current medical practice involves the irradiation of blood components, including platelet concentrates, before their administration to patients with severe immunosuppression. The authors studied the effect of irradiation on in vitro platelet function and the leaching of plasticizers from the bag, both immediately and after 5 days of storage. The platelet count, white cell count, pH, glucose, lactate, platelet aggregation and release reaction, and serotonin uptake were not altered by the irradiation of random-donor or apheresis units with 2000 rads carried out at 0 and 24 hours and 5 days after collection. The leaching of di(2-ethylhexyl)phthalate from the plastic bags followed by the conversion to mono(2-ethylhexyl)phthalate was not increased by irradiation. Therefore, it is possible to irradiate platelet concentrates on the day of collection and subsequently store them for at least 5 days while maintaining in vitro function. This procedure could have considerable benefit for blood banks involved in the provision of many platelet products.

  8. Reticulocyte count

    MedlinePlus

    Anemia - reticulocyte ... A higher than normal reticulocytes count may indicate: Anemia due to red blood cells being destroyed earlier than normal ( hemolytic anemia ) Bleeding Blood disorder in a fetus or newborn ( ...

  9. Qualitative disorders of platelets and megakaryocytes.

    PubMed

    Nurden, A T

    2005-08-01

    Qualitative disorders of platelet function and production form a large group of rare diseases which cover a multitude of genetic defects that by and large have as a common symptom, excessive mucocutaneous bleeding. Glanzmann thrombasthenia, is enabling us to learn much about the pathophysiology of integrins and of how alphaIIb beta3 functions. Bernard-Soulier syndrome, an example of macrothrombocytopenia, combines the production of large platelets with a deficit or non-functioning of the major adhesion receptor of platelets, the GPIb-IX-V complex. Amino acid substitutions in GPIb alpha, may lead to up-regulation and spontaneous binding of von Willebrand factor as in Platelet-type von Willebrand disease. In disorders with defects in the MYH9 gene, macrothrombocytopenias are linked to modifications in kidney, eye or ear, whereas other inherited thrombocytopenias variously link a low platelet count with a propensity to leukemia, skeletal defects, learning impairment, and abnormal red cells. Defects of secretion from platelets include an abnormal alpha-granule formation as in the gray platelet syndrome (with marrow myelofibrosis), and of organelle biogenesis in the Hermansky-Pudlak and Chediak-Higashi syndromes where platelet dense body defects are linked to abnormalities of other lysosomal-like organelles including melanosomes. Finally, defects involving surface receptors (P2Y(12), TPalpha) for activating stimuli, of proteins essential for signaling pathways (including Wiskott-Aldrich syndrome), and of platelet-derived procoagulant activity (Scott syndrome) show how studies on platelet disorders are helping unravel the pathways of primary hemostasis.

  10. Tower counts

    USGS Publications Warehouse

    Woody, Carol Ann; Johnson, D.H.; Shrier, Brianna M.; O'Neal, Jennifer S.; Knutzen, John A.; Augerot, Xanthippe; O'Neal, Thomas A.; Pearsons, Todd N.

    2007-01-01

    Counting towers provide an accurate, low-cost, low-maintenance, low-technology, and easily mobilized escapement estimation program compared to other methods (e.g., weirs, hydroacoustics, mark-recapture, and aerial surveys) (Thompson 1962; Siebel 1967; Cousens et al. 1982; Symons and Waldichuk 1984; Anderson 2000; Alaska Department of Fish and Game 2003). Counting tower data has been found to be consistent with that of digital video counts (Edwards 2005). Counting towers do not interfere with natural fish migration patterns, nor are fish handled or stressed; however, their use is generally limited to clear rivers that meet specific site selection criteria. The data provided by counting tower sampling allow fishery managers to determine reproductive population size, estimate total return (escapement + catch) and its uncertainty, evaluate population productivity and trends, set harvest rates, determine spawning escapement goals, and forecast future returns (Alaska Department of Fish and Game 1974-2000 and 1975-2004). The number of spawning fish is determined by subtracting subsistence, sport-caught fish, and prespawn mortality from the total estimated escapement. The methods outlined in this protocol for tower counts can be used to provide reasonable estimates ( plus or minus 6%-10%) of reproductive salmon population size and run timing in clear rivers. 

  11. [Platelet transfusion role in neonatal immune thrombocytopenia].

    PubMed

    Petermann, R

    2016-11-01

    Neonatal immune thrombocytopenia represent less than 5% of cases of early thrombocytopenia (early-onset<72hours post-delivery). As in adults, thrombocytopenia in neonates is defined as a platelet count less than 150G/L. They are either auto- or allo-immune. Thrombocytopenia resulting from transplacental passage of maternal antibodies directed to platelet membrane glycoproteins can be severe. The major complication of severe thrombocytopenia is bleeding and particularly intra-cranial haemorrhage and neurologic sequelea following. However, auto- and allo-immune thrombocytopenia have very different characteristics including the treatment management. In fact, this treatment is based on platelet transfusion associated or not to intravenous immunoglobulin administration. The purpose of this article is to remind platelet transfusion's place in neonatal immune thrombocytopenia in terms of recently published French guidelines and international practices.

  12. Human Platelet Senescence.

    DTIC Science & Technology

    1976-04-30

    electrophoresis platelet subpopulations membranes enrichment of platelet collections with miigathrombocytes 20. A DST RAC T (Cpntinue on reverse&. "~gaU...label which enters megakaryocytes but not peripheral blood platelets. Platelets re- leased from the bone marrow however, do contain the isotope . With...their own platelet-rich plasma (anticoagulated with ACD-A) at 800 RP’M) 1200 RPM, 1600 RPM, 1800 RPM and 2000 RPM in a Sorvall RC3 Centrifugue . The

  13. [In vitro platelet production].

    PubMed

    Dunois-Lardé, C; Baruch, D

    2011-04-01

    This review aims at presenting a state of the art on platelet functions, not only in well-characterized hemostasis and thrombosis, but also in various domains such as inflammation, immunity, angiogenesis, source of growth factors, metastasis and vascular remodelling. This multivalent phenotype of platelets suggests new potential applications of platelets. The second objective is to present new advances in platelet formation from megakaryocytes and direct platelet release, as initially shown by our group and more recently by others.

  14. Geometric complexity is increased in in vitro activated platelets.

    PubMed

    Bianciardi, Giorgio

    2015-06-01

    This article investigates the use of computerized fractal analysis for objective characterization of the complexity of platelets in vitro stimulated by low level thrombin (0.02 U mL(-1) ), collected from healthy individuals and observed by means of transmission electron microscopy. Platelet boundaries were extracted by means of automatically image analysis. Local fractal dimension was evaluated by the box-counting technique (measure of geometric complexity of the platelet outline). The results showed that the platelet boundary is fractal when observed by transmission electron microscopy and that, after an in vitro platelet activation test, the shape of platelets present increased geometric complexity in comparison to the no stimulated platelets (P < 0.001), with 100% correct classification. Computerized fractal analysis of platelet shape by transmission electron microscopy can provide accurate, quantitative, data to study platelet activation. The results may play important roles in the evaluation of the platelets status in pathological conditions, like as atherosclerosis and diabetes mellitus, where in in vivo activated platelets have been described.

  15. Characterization of Platelet Concentrates Using Dynamic Light Scattering

    PubMed Central

    Labrie, Audrey; Marshall, Andrea; Bedi, Harjot; Maurer-Spurej, Elisabeth

    2013-01-01

    Summary Background Each year, millions of platelet transfusions save the lives of cancer patients and patients with bleeding complications. However, between 10 and 30% of all platelet transfusions are clinically ineffective as measured by corrected count increments, but no test is currently used to identify and avoid these transfusions. ThromboLUX® is the first platelet test intended to routinely characterize platelet concentrates prior to transfusion. Methods ThromboLUX is a non-invasive, optical test utilizing dynamic light scattering to characterize a platelet sample by the relative quantity of platelets, microparticles, and other particles present in the sample. ThromboLUX also determines the response of platelets to temperature changes. From this information the ThromboLUX score is calculated. Increasing scores indicate increasing numbers of discoid platelets and fewer microparticles. ThromboLUX uses calibrated polystyrene beads as a quality control standard, and accurately measures the size of the beads at multiple temperatures. Results Results from apheresis concentrates showed that ThromboLUX can determine the microparticle content in unmodified samples of platelet concentrates which correlates well with the enumeration by flow cytometry. ThromboLUX detection of microparticles and microaggregates was confirmed by microscopy. Conclusion ThromboLUX provides a comprehensive and novel analysis of platelet samples and has potential as a noninvasive routine test to characterize platelet products to identify and prevent ineffective transfusions. PMID:23652319

  16. Neonatal thrombocytopenia and platelet transfusion - a UK perspective.

    PubMed

    Carr, Robert; Kelly, Anne M; Williamson, Lorna M

    2015-01-01

    Five percent of newborn infants admitted to UK neonatal units during a recent study developed a platelet count <60 × 10(9)/l, and 60% of these were transfused platelets. This review summarises the common causes and mechanisms of thrombocytopenia in the newborn. Relevant evidence relating the platelet count to the risk of haemorrhage is reviewed, and current UK guidance on transfusion thresholds outlined. The UK policy for the provision of platelets for transfusion to neonates is described, including the particular requirements for neonatal allo-immune thrombocytopenia. Finally, we look towards the future and prospects for reducing the need to expose newborns to donor-derived platelets. © 2014 S. Karger AG, Basel.

  17. Platelet-leukocyte mixed conjugates in patients with atrial fibrillation.

    PubMed

    Alberti, Silvia; Angeloni, Giulia; Tamburrelli, Chiara; Pampuch, Agnieszka; Izzi, Benedetta; Messano, Loredana; Parisi, Quintino; Santamaria, Matteo; Donati, Maria Benedetta; de Gaetano, Giovanni; Cerletti, Chiara

    2009-06-01

    Although platelets may contribute to the inflammatory component in atrial fibrillation (AF), the impact of platelet-leukocyte mixed conjugates has not yet been determined. Seventeen patients with persistent AF (8/9 m/f; mean age 68.1 +/- 2.5 years), not on anticoagulant therapy, were recruited and compared to 34 healthy controls with normal sinus rhythm (16/18 m/f; mean age 60.8 +/- 1.2 years). Platelet-leukocyte mixed conjugates, platelet P-selectin and leukocyte activation markers (CD11b, myeloperoxidase) were measured by flow-cytometry in whole blood both in basal condition and after in vitro ADP/collagen challenge. Plasma D-dimer and soluble P-selectin were also measured. Statistical analyses were performed by Mann-Whitney or Wilcoxon U test for intergroup differences. In AF patients platelet count, as well as platelet P-selectin expression and percent platelet-leukocyte conjugates were all significantly lower both in basal condition and upon activation with ADP/collagen. In contrast, both soluble P-selectin and D-dimer were significantly higher than in controls; white blood cell count and leukocyte activation markers were unchanged. In conclusion, the formation of platelet-leukocyte mixed conjugates was unexpectedly reduced in AF, possibly due to less reactive platelets as a consequence of previous in vivo activation by ongoing formation of trace amounts of thrombin.

  18. Primary refractoriness to platelet transfusion caused by Nak(a) antibody alone.

    PubMed

    Fujino, H; Ohta, K; Taniue, J; Nagao, N; Hino, M; Yamane, T; Koh, K R; Takeoka, Y; Hirose, A; Aoyama, Y; Nakamae, H; Terada, Y; Takubo, T; Tatsumi, N; Taniue, A

    2001-07-01

    Anti-Nak(a), a platelet-specific antibody, occasionally causes platelet-transfusion refractoriness (PTR) together with human leucocyte antigen (HLA) antibodies. Anti-Nak(a) usually appears after frequent platelet transfusions or pregnancy. We report the first case of PTR caused by anti-Nak(a) alone. A 19-year-old male patient with testicular tumour showed PTR when receiving his first transfusion of platelets. Screening for platelet antigens and platelet antibodies revealed that he had type I CD36 (Nak(a)) deficiency and that anti-Nak(a), but not anti-HLA, was present before he received his first transfusion. The transfusion of Nak(a)-negative, but HLA non-selected, platelets was effective in raising the platelet count. Clinically significant Nak(a) antibody was present as naturally occurring antibody in a platelet glycoprotein IV (CD36)-negative non-transfused male patient.

  19. Modified CMI, an essential adjunct to CMI of platelet for quality control during preparation and storage of platelet concentrates.

    PubMed

    Ray, Vijayalaxmi; Chaudhary, Rajendra; Singh, Harprit

    2003-10-01

    Changes in platelet indices such as platelet count (PLT), mean platelet volume (MPV) and corrected morphological index (CMI) have been correlated with the quality of platelet concentrates during storage but the acceptability criteria for these is not clearly defined. Platelet distribution width (PDW) is a measure of platelet anisocytosis and together with the MPV provides an adjunctive measure of quality. Hence, we investigated the use of the MPV and PDW with and without EDTA in an assessment of the quality of stored platelet concentrates. The differences in platelet count (dPLT), in MPV (dMPV) and in PDW (dPDW) with and without EDTA incubation were calculated. CMI and the modified CMI were further derived using dPLT, dMPV, and dPDW by simple mathematical calculations. We observed a good correlation of the CMI and modified CMI (r=0.966, p<0.01). The dPDWs underwent significant changes during the storage period in addition to changes in dPLT and dMPV. The dPDW provides a test of good power when compared with the dMPV (R(2)=64.1 and 26.1 respectively). We have observed an increment of 92.76% in the dPDW while it was 71% in the dMPV. This clearly shows that the dPDW is a better marker of quality control when compared to the dMPV during processing and storage of platelet concentrates.

  20. White Blood Cell Count

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? ... Count; Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , ...

  1. [Indications and surveillance of platelet transfusions in surgery].

    PubMed

    Coffe, C; Bardiaux, L; Couteret, Y; Devillers, M; Leroy, M; Morel, P; Pouthier-Stein, F; Hervé, P

    1995-01-01

    Surgery, after hematology, is the biggest consumer of homologous platelet concentrates. Platelet transfusion is indicated to prevent or control bleeding associated with deficiencies in platelet number or function. In surgery, general patterns (in function of pre-surgery platelet count) can be adopted in most of the indications for platelets. In emergency situations, and in some particular cases (related to the patient, the type of operation, etc.), the transfusion procedure depends on the team's experience, the results of the available clinical and biological tests, and the drugs. Strict monitoring is required during the transfusion procedure. The efficacy of the transfusion must be controlled 1 h and 24 hours after the transfusion, and a number of factors must be assessed, namely the immunological impact of the transfusion (on red blood cells, leukocytes and platelets) and the occurrence of infectious diseases transmitted via transfusion. In addition, for a possible future transfusion, a strategy must be proposed.

  2. Platelet concentration in platelet concentrates and periodontal regeneration-unscrambling the ambiguity

    PubMed Central

    Suchetha, A.; Lakshmi, P.; Bhat, Divya; Mundinamane, Darshan B.; Soorya, K. V.; Bharwani, G. Ashit

    2015-01-01

    Context: Platelet-rich-plasma (PRP) and Platelet-rich-fibrin (PRF) are extensively used autologous platelet concentrates in periodontal regeneration, and PRF has a better efficacy as compared to PRP. The rationale for this difference has often been attributed to the difference in the structure of the fibrin matrix. However, the effect of concentration of platelets on the regenerative potential of these concentrates is obscure. Aims: The study was conducted to evaluate and compare, clinically and radiographically, the efficacy of PRF and PRP in the treatment of periodontal endosseous defects and to assess the effect of platelet concentration on periodontal regeneration. Materials and Methods: Twenty intrabony defects were selected and divided into two groups randomly by the coin toss method. Group I received PRP and Group II subjects were treated with PRF. The platelet counts in PRP and PRF were analyzed. Clinical and radiological parameters were assessed at baseline and 3, 6, and 9 months postoperatively. Statistical Analysis: Kruskal–Wallis Chi-square test, Wilcoxon signed rank test, t-test, and Spearman's rank correlation were used for statistical analysis of data. Results: There was statistically significant improvement in all the parameters in the two groups except in relation to gingival recession. There was a statistically significant difference between the platelet count in Group I and Group II (P = 0.002). Conclusion: PRP and PRF appear to have nearly comparable effects in terms of periodontal regeneration. The concentration of platelets appears to play a paradoxical role in regeneration. The regenerative potential of platelets appears to be optimal within a limited range. PMID:26681857

  3. Platelet Transfusion Practices in the ICU: Data From a Large Transfusion Registry.

    PubMed

    Ning, Shuoyan; Barty, Rebecca; Liu, Yang; Heddle, Nancy M; Rochwerg, Bram; Arnold, Donald M

    2016-09-01

    Platelet transfusions are commonly used in critically ill patients, but transfusion thresholds, count increments, and predictors of ineffectual transfusions remain unclear. This retrospective study included consecutive adult nononcology patients who received platelet transfusions in ICUs at three Canadian academic hospitals between 2006 and 2015. Data were collected from a validated transfusion database. We determined independent predictors of ineffectual platelet transfusions, defined as transfusions that raised platelet counts by < 5 × 10(9)/L. Reasons for transfusion were adjudicated in a subgroup of patients who underwent transfusion despite normal platelet counts. We identified 7,320 ICU admissions (n = 7,073 patients) during which 15,879 platelet transfusions were administered. Most admissions (78.7%) were for cardiac surgery. Based on 5,700 analyzable transfusions, the median pretransfusion platelet count was 87 × 10(9)/L (interquartile range [IQR], 57-130). The pretransfusion platelet count was ≥ 50 × 10(9)/L and ≥ 150 × 10(9)/L for 79.6% and 17.8% of transfusions, respectively. Reasons for transfusion despite a normal platelet count were active bleeding or surgery in patients receiving antiplatelet agents or anticoagulants. The median platelet count increment was 23 × 10(9)/L (IQR, 7-44), and 21.8% of transfusions were ineffectual. ABO incompatibility, sepsis, liver disease, and red cell and cryoprecipitate transfusions were associated with a poor platelet count increment. Platelet transfusions were commonly used in the ICU when platelet counts were ≥ 50 × 10(9)/L. One platelet transfusion increased platelet count by 23 × 10(9)/L. One in five transfusions was ineffectual, and ABO incompatibility was identified as a modifiable risk factor. These data can help direct efforts to reduce platelet overuse and improve transfusion quality. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights

  4. Counting Penguins.

    ERIC Educational Resources Information Center

    Perry, Mike; Kader, Gary

    1998-01-01

    Presents an activity on the simplification of penguin counting by employing the basic ideas and principles of sampling to teach students to understand and recognize its role in statistical claims. Emphasizes estimation, data analysis and interpretation, and central limit theorem. Includes a list of items for classroom discussion. (ASK)

  5. Counting Populations

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    Scientists use sampling to get an estimate of things they cannot easily count. A population is made up of all the organisms of one species living together in one place at the same time. All of the people living together in one town are considered a population. All of the grasshoppers living in a field are a population. Scientists keep track of the…

  6. Counting Penguins.

    ERIC Educational Resources Information Center

    Perry, Mike; Kader, Gary

    1998-01-01

    Presents an activity on the simplification of penguin counting by employing the basic ideas and principles of sampling to teach students to understand and recognize its role in statistical claims. Emphasizes estimation, data analysis and interpretation, and central limit theorem. Includes a list of items for classroom discussion. (ASK)

  7. Counting Populations

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    Scientists use sampling to get an estimate of things they cannot easily count. A population is made up of all the organisms of one species living together in one place at the same time. All of the people living together in one town are considered a population. All of the grasshoppers living in a field are a population. Scientists keep track of the…

  8. Platelet-mimetic strategies for modulating the wound environment and inflammatory responses

    PubMed Central

    Nandi, Seema

    2016-01-01

    Platelets closely interface with the immune system to fight pathogens, target wound sites, and regulate tissue repair. Natural platelet levels within the body can be depleted for a variety of reasons, including excessive bleeding following traumatic injury, or diseases such as cancer and bacterial or viral infections. Platelet transfusions are commonly used to improve platelet count and hemostatic function in these cases, but transfusions can be complicated by the contamination risks and short storage life of donated platelets. Lyophilized platelets that can be freeze-dried and stored for longer periods of time and synthetic platelet-mimetic technologies that can enhance or replace the functions of natural platelets, while minimizing adverse immune responses have been explored as alternatives to transfusion. Synthetic platelets typically comprise nanoparticles surface-decorated with peptides or ligands to recreate specific biological characteristics of platelets, including targeting of wound and disease sites and facilitating platelet aggregation. Recent efforts in synthetic platelet design have additionally focused on matching platelet shape and mechanics to recreate the marginalization and clot contraction capabilities of natural platelets. The ability to specifically tune the properties of synthetic platelet-mimetic materials has shown utility in a variety of applications including hemostasis, drug delivery, and targeted delivery of cancer therapeutics. PMID:27190260

  9. White blood cell counts: reference methodology.

    PubMed

    Chabot-Richards, Devon S; George, Tracy I

    2015-03-01

    Modern hematology laboratories use automated hematology analyzers to perform cell counts. These instruments provide accurate, precise, low-cost differential counts with fast turnaround times. Technologies commonly used include electrical impedance, radiofrequency conductivity, laser light scattering, and cytochemistry. This article reviews the principles of these methodologies and possible sources of error, provides guidance for selecting flagging criteria, and discusses novel, clinically relevant white blood cell parameters provided by new instruments, including immature granulocyte count and granularity index.

  10. The effect of variation in donor platelet function on transfusion outcome: a semirandomized controlled trial.

    PubMed

    Kelly, Anne M; Garner, Stephen F; Foukaneli, Theodora; Godec, Thomas R; Herbert, Nina; Kahan, Brennan C; Deary, Alison; Bakrania, Lekha; Llewelyn, Charlotte; Ouwehand, Willem H; Williamson, Lorna M; Cardigan, Rebecca A

    2017-07-13

    The effect of variation in platelet function in platelet donors on patient outcome following platelet transfusion is unknown. This trial assessed the hypothesis that platelets collected from donors with highly responsive platelets to agonists in vitro assessed by flow cytometry (high-responder donors) are cleared more quickly from the circulation than those from low-responder donors, resulting in lower platelet count increments following transfusion. This parallel group, semirandomized double-blinded trial was conducted in a single center in the United Kingdom. Eligible patients were those 16 or older with thrombocytopenia secondary to bone marrow failure, requiring prophylactic platelet transfusion. Patients were randomly assigned to receive a platelet donation from a high- or low-responder donor when both were available, or when only 1 type of platelet was available, patients received that. Participants, investigators, and those assessing outcomes were masked to group assignment. The primary end point was the platelet count increment 10 to 90 minutes following transfusion. Analysis was by intention to treat. Fifty-one patients were assigned to receive platelets from low-responder donors, and 49 from high-responder donors (47 of which were randomized and 53 nonrandomized). There was no significant difference in platelet count increment 10 to 90 minutes following transfusion in patients receiving platelets from high-responder (mean, 21.0 × 10(9)/L; 95% confidence interval [CI], 4.9-37.2) or low-responder (mean, 23.3 × 10(9)/L; 95% CI, 7.8-38.9) donors (mean difference, 2.3; 95% CI, -1.1 to 5.7; P = .18). These results support the current policy of not selecting platelet donors on the basis of platelet function for prophylactic platelet transfusion. © 2017 by The American Society of Hematology.

  11. Recommendation for standardization of haematology reporting units used in the extended blood count.

    PubMed

    Brereton, M; McCafferty, R; Marsden, K; Kawai, Y; Etzell, J; Ermens, A

    2016-10-01

    It is desirable in the interest of patient safety that the reporting of laboratory results should be standardized where no valid reason for diversity exists. This study considers the reporting units used for the extended blood cell count and makes a new ICSH recommendation to encourage standardization worldwide. This work is based on a literature review that included the original ICSH recommendations and on data gathered from an international survey of current practice completed by 18 countries worldwide. The survey results show that significant diversity in the use of reporting units for the blood count exists worldwide. The use of either non-SI or other units not recommended by the ICSH in the early 1980s has persisted despite the guidance from that time. The diversity in use of reporting units occurs in three areas: the persistence in use of non-SI units for RBC, WBC and platelet counts, the use of three different units for haemoglobin concentration and the manual reporting of WBC differential, reticulocytes and nucleated RBCs when the latter are available from automated analysis or can be expressed as absolute numbers by calculation. A new recommendation with a rationale for each parameter is made for standardization of the reporting units used for the extended blood count. © 2016 John Wiley & Sons Ltd.

  12. Clinical application of radiolabelled platelets

    SciTech Connect

    Kessler, C. )

    1990-01-01

    This book presents papers on the clinical applications of radiolabelled platelets. The papers are grouped into six sections on platelet labelling techniques, radiolabelled platelets in cardiology, monitoring of antiplatelet therapy, platelet scintigraphy in stroke patients, platelet scintigraphy in angiology, and platelet scintigraphy in hematology and other clinical applications, including renal transplant rejection.

  13. Improving the bacteriological safety of platelet transfusions.

    PubMed

    Blajchman, Morris A; Goldman, Mindy; Baeza, Federico

    2004-01-01

    Despite the increased application of aseptic techniques for blood collection and the preparation of platelet concentrates, morbidity and mortality arising from the transfusion of bacterially contaminated allogeneic platelet products persist. This problem exists because stored platelet concentrates represent a nearly ideal growth medium for bacteria and because they are stored at temperatures (22 degrees +/- 2 degrees C) that facilitate bacterial growth. The presence of bacteria in blood components including platelets has been a problem for many decades and currently is the most common microbiological cause of transfusion-associated morbidity and mortality. A variety of strategies have been devised and/or proposed in an attempt to try to reduce the risk of transfusion-associated sepsis. These include pretransfusion bacterial detection, efforts to reduce the likelihood of bacterial contamination, the optimization of blood product processing and storage, reducing recipient exposure, and the introduction of pathogen inactivation methodology. With regard to doing bacterial detection, a number of automated detection systems have become available to test for contaminated platelet components, but their utility to some extent is restricted by the time they take to indicate the presence of bacteria and/or their lack of sensitivity to detect initially low bacterial loads. A variety of other approaches has been shown to reduce the risk of bacterial contamination and include filtration to remove leukocytes and bacteria, diversion of the initial aliquot of blood during donation, and improved donor skin disinfection. Platelet pathogen inactivation methods under investigation include the addition of L-carnitine, gamma-irradiation, riboflavin plus UVA irradiation, and amotosalen HCl plus UVA irradiation. The latter process is licensed for clinical use with platelets in some countries in Europe. All of these approaches, either collectively or individually, hold considerable promise

  14. Platelet function and activation in Cavalier King Charles Spaniels with subclinical chronic valvular heart disease.

    PubMed

    Tong, Linda J; Hosgood, Giselle L; French, Anne T; Irwin, Peter J; Shiel, Robert E

    2016-08-01

    OBJECTIVE To assess platelet closure time (CT), mean platelet component (MPC) concentration, and platelet component distribution width (PCDW) in dogs with subclinical chronic valvular heart disease. ANIMALS 89 Cavalier King Charles Spaniels (CKCSs) and 39 control dogs (not CKCSs). PROCEDURES Platelet count, MPC concentration, PCDW, and Hct were measured by use of a hematology analyzer, and CT was measured by use of a platelet function analyzer. Murmur grade and echocardiographic variables (mitral valve regurgitant jet size relative to left atrial area, left atrial-to-aortic diameter ratio, and left ventricular internal dimensions) were recorded. Associations between explanatory variables (sex, age, murmur grade, echocardiographic variables, platelet count, and Hct) and outcomes (CT, MPC concentration, and PCDW) were examined by use of multivariate regression models. RESULTS A model with 5 variables best explained variation in CT (R(2), 0.74), with > 60% of the variance of CT explained by mitral valve regurgitant jet size. The model of best fit to explain variation in MPC concentration included only platelet count (R(2), 0.24). The model of best fit to explain variation in PCDW included platelet count and sex (R(2), 0.25). CONCLUSIONS AND CLINICAL RELEVANCE In this study, a significant effect of mitral valve regurgitant jet size on CT was consistent with platelet dysfunction. However, platelet activation, as assessed on the basis of the MPC concentration and PCDW, was not a feature of subclinical chronic valvular heart disease in CKCSs.

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

    PubMed Central

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

    2016-01-01

    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

  16. Platelet antibody in prolonged remission of childhood idiopathic thrombocytopenic purpura

    SciTech Connect

    Ware, R.; Kinney, T.R.; Rosse, W.

    1985-11-01

    Evaluations were performed in 20 patients with childhood idiopathic thrombocytopenic purpura (ITP) who remained in remission longer than 12 months. The mean duration of follow-up from diagnosis was 39 months (range 17 to 87 months). Eleven patients (four girls) in group 1 had an acute course of ITP, defined as platelet count greater than 150 X 10(9)/L within 6 months of diagnosis. Nine patients (five girls) in group 2 had a chronic course, defined as platelet count less than 150 X 10(9)/L for greater than or equal to 1 year or requiring splenectomy in an attempt to control hemorrhagic symptoms. Platelet count and serum (indirect) platelet-associated IgG (PAIgG) levels were normal in all 20 patients at follow-up. Both direct and indirect PAIgG levels were measured using a SVI-monoclonal anti-IgG antiglobulin assay. All had normal direct PAIgG levels, except for one patient in group 1 who had a borderline elevated value of 1209 molecules per platelet. These data suggest that the prevalence of elevated platelet antibodies is low during sustained remission without medication in patients with a history of childhood ITP. These data may be relevant for pregnant women with a history of childhood ITP, with regard to the risk of delivering an infant with thrombocytopenia secondary to transplacental passage of maternal platelet antibody.

  17. Thrombocytopenia in leptospirosis and role of platelet transfusion

    PubMed Central

    Sharma, Jayashree; Suryavanshi, Moushumi

    2007-01-01

    Aim: The study was designed to find out the incidence of thrombocytopenia in leptospirosis and to correlate thrombocytopenia with other parameters like renal failure, hepatic failure and bleeding manifestation like adult respiratory distress syndrome and to assess the role of platelet transfusion. Materials and Methods: 50 cases of leptospirosis during the month of July and August 2005 were retrospectively analyzed. Criteria for selection were Lepto Tek Dri - dot test positive cases of the clinically suspected cases of Leptospirosis. Degree of thrombocytopenia was categorized as severe, moderate and mild. Presence of thrombocytopenia was clinically correlated with parameters like renal dysfunction, hepatic dysfunction and hemorrhagic manifestations (mainly ARDS). Role of platelet transfusion was assessed with reference to presence and degree of thrombcytopenia and hemorrhagic manifestations. Results: Out of total 50 patients 26 were male and 24 were females. Major bleeding manifestation in the form of ARDS was seen in 15 (30%) of patients. 28 (56%) patients had thrombocytopenia and 22 (44%) patients had normal platelet counts. Total number of patients with renal dysfunction was 24 (48%). Only four (18.18%) patients with normal platelet counts had renal dysfunction while 20 (71.42%) patients with thrombocytopenia had renal dysfunction. Only two (9.09%) patients with normal platelet counts and 48 (46.42%) patients with thrombocytopenia had hepatorenal dysfunction. Total number of patients with ARDS was 15 (30%). Of these two (13.33%) had normal platelet count while 13 (86.6%) patients were thrombocytopenic. Total 47 units of platelets were transfused to 12 patients in our study. Of these seven patients with severe thrombocytopenia required total 28 units, two patients with moderate thrombocytopenia required total seven units and patients with mild thrombocytopenia were transfused total 12 units of platelets. Conclusion: It is important to anticipate and recognize

  18. The Influence of Haemoglobin A1c Levels on Platelet Aggregation and Platelet Turnover in Patients with Coronary Artery Disease Treated with Aspirin

    PubMed Central

    Neergaard-Petersen, Søs; Hvas, Anne-Mette; Grove, Erik Lerkevang; Larsen, Sanne Bøjet; Gregersen, Søren; Kristensen, Steen Dalby

    2015-01-01

    Background Hyperglycaemia may attenuate the antiplatelet effect of aspirin and thereby increase the risk of cardiovascular events. We investigated the influence of increased haemoglobin A1c (HbA1c) levels on platelet aggregation and turnover in a large cohort of patients with coronary artery disease (CAD) with type 2 diabetes, prediabetes or no diabetes. Methods In this observational study, we included 865 stable CAD patients on 75 mg aspirin as mono-therapy of whom 242 patients had type 2 diabetes and were receiving antidiabetic drugs. Among 623 patients without diabetes, we classified 303 patients with prediabetes (HbA1c ≥5.7–6.4% [39–47 mmol/mol]) naive to antidiabetic drugs. Platelet aggregation was evaluated by the Multiplate Analyzer using arachidonic acid and collagen and by the VerifyNow Aspirin. Platelet turnover was evaluated by immature platelets using flow cytometry and platelet activation by soluble P-selectin. Results CAD patients with type 2 diabetes had higher platelet aggregation (all p-values <0.01), platelet turnover (immature platelet count, p<0.01) and platelet activation (p<0.001) than patients without diabetes. CAD patients with prediabetes had increased platelet aggregation (p = 0.02) and platelet count (p = 0.02) compared with patients without diabetes. Increased levels of HbA1c correlated positively with increased platelet aggregation using arachidonic acid (r = 0.19, p<0.0001), collagen (r = 0.10, p<0.01) and VerifyNow (r = 0.15, p<0.0001), and with platelet count (r = 0.08, p = 0.01), immature platelet count (r = 0.11, p<0.001) and soluble P-selectin (r = 0.15, p<0.0001). These associations were mainly evident in non-diabetic and prediabetic CAD patients. Conclusions CAD patients with prediabetes and diabetes may have attenuated antiplatelet effect of aspirin compared with CAD patients without diabetes. This may be related to increased platelet count in patients with prediabetes. Increased levels of HbA1c correlated positively

  19. Proliferation-promoting effect of platelet-rich plasma on human adipose-derived stem cells and human dermal fibroblasts.

    PubMed

    Kakudo, Natsuko; Minakata, Tatsuya; Mitsui, Toshihito; Kushida, Satoshi; Notodihardjo, Frederik Zefanya; Kusumoto, Kenji

    2008-11-01

    This study evaluated changes in platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 release from platelets by platelet-rich plasma activation, and the proliferation potential of activated platelet-rich plasma and platelet-poor plasma on human adipose-derived stem cells and human dermal fibroblasts. Platelet-rich plasma was prepared using a double-spin method, with the number of platelets counted in each preparation stage. Platelet-rich and platelet-poor plasma were activated with autologous thrombin and calcium chloride, and levels of platelet-released PDGF-AB and TGF-beta1 were determined by enzyme-linked immunosorbent assay. Cells were cultured for 1, 4, or 7 days in serum-free Dulbecco's Modified Eagle Medium supplemented with 5% whole blood plasma, nonactivated platelet-rich plasma, nonactivated platelet-poor plasma, activated platelet-rich plasma, or activated platelet-poor plasma. In parallel, these cells were cultured for 1, 4, or 7 days in serum-free Dulbecco's Modified Eagle Medium supplemented with 1%, 5%, 10%, or 20% activated platelet-rich plasma. The cultured human adipose-derived stem cells and human dermal fibroblasts were assayed for proliferation. Platelet-rich plasma contained approximately 7.9 times as many platelets as whole blood, and its activation was associated with the release of large amounts of PDGF-AB and TGF-beta1. Adding activated platelet-rich or platelet-poor plasma significantly promoted the proliferation of human adipose-derived stem cells and human dermal fibroblasts. Adding 5% activated platelet-rich plasma to the medium maximally promoted cell proliferation, but activated platelet-rich plasma at 20% did not promote it. Platelet-rich plasma can enhance the proliferation of human adipose-derived stem cells and human dermal fibroblasts. These results support clinical platelet-rich plasma application for cell-based, soft-tissue engineering and wound healing.

  20. C-reactive protein, platelets, and patent ductus arteriosus.

    PubMed

    Meinarde, Leonardo; Hillman, Macarena; Rizzotti, Alina; Basquiera, Ana Lisa; Tabares, Aldo; Cuestas, Eduardo

    2016-12-01

    The association between inflammation, platelets, and patent ductus arteriosus (PDA) has not been studied so far. The purpose of this study was to evaluate whether C-reactive protein (CRP) is related to low platelet count and PDA. This was a retrospective study of 88 infants with a birth weight ≤1500 g and a gestational age ≤30 weeks. Platelet count, CRP, and an echocardiogram were assessed in all infants. The subjects were matched by sex, gestational age, and birth weight. Differences were compared using the χ(2), t-test, or Mann-Whitney U-test, as appropriate. Significant variables were entered into a logistic regression model. The association between CRP and platelets was evaluated by correlation and regression analysis. Platelet count (167 000 vs. 213 000 µl(-1), p = 0.015) was lower and the CRP (0.45 vs. 0.20 mg/dl, p = 0.002) was higher, and the platelet count correlated inversely with CRP (r = -0.145, p = 0.049) in the infants with vs. without PDA. Only CRP was independently associated with PDA in a logistic regression model (OR 64.1, 95% confidence interval 1.4-2941, p = 0.033).

  1. Platelet antibody in idiopathic thrombocytopenic purpura and other thrombocytopenias

    SciTech Connect

    Sugiura, K.; Steiner, M.; Baldini, M.G.

    1980-10-01

    Platelet-associated immunoglobulin was measured by the use of fluorescent anti-1gG antibody. The method is simple, rapid, and sensitive and provides a precise quantitive assay of bound (direct) and free (indirect) 1gG with platelet specificity. We have evaluated this test in 30 normal volunteers and in 50 patients with immune and nonimmune, treated and untreated thrombocytopenias. All patients with immune thrombocytopenias (acute and chronic idiopathic thrombocytopenic purpura and systemic lupus erythematosus) having platelet counts < 100,000/..mu..l had elevated levels of platelet-bound 1gG and 86% had also positive results in the indirect assay. All patients with nonimmunological thrombocytopenias showed normal results in the direct and indirect assay of platelet-associated immunoglobulin. In patients studied repeatedly during the course of their illness, an inverse relation was found between platelet count and level of platelet-bound 1gG. Patients with systemic lupus erythematosus presented clear exceptions to this rule. Investigations of the absorbability of platelet autoantibodies and alloantibodies showed that this assay can readily differentiate between these two antibody species and can also identify specificities of alloantibodies.

  2. The omnipotent platelet.

    PubMed

    Steinberg, L A

    1996-03-01

    This information was derived from the increase in platelets of patients following fractures and/or bone surgery and in conjunction with a vast amount of published literature. The increase in numbers of platelets reflects the extent of bone involvement, especially noted in the hip, knee, post-coronary artery bypass graft, and multiple fractures. The role of the platelet in any and all tissues, i.e. soft tissue or bone, whether beneficial or detrimental, is multifunctional. The platelet responds to all physiologic and pathologic states and, if tissue involved is sufficient, the role of the platelet becomes obvious.

  3. Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4.

    PubMed

    Semeraro, Fabrizio; Ammollo, Concetta T; Morrissey, James H; Dale, George L; Friese, Paul; Esmon, Naomi L; Esmon, Charles T

    2011-08-18

    The release of histones from dying cells is associated with microvascular thrombosis and, because histones activate platelets, this could represent a possible pathogenic mechanism. In the present study, we assessed the influence of histones on the procoagulant potential of human platelets in platelet-rich plasma (PRP) and in purified systems. Histones dose-dependently enhanced thrombin generation in PRP in the absence of any trigger, as evaluated by calibrated automated thrombinography regardless of whether the contact phase was inhibited. Activation of coagulation required the presence of fully activatable platelets and was not ascribable to platelet tissue factor, whereas targeting polyphosphate with phosphatase reduced thrombin generation even when factor XII (FXII) was blocked or absent. In the presence of histones, purified polyphosphate was able to induce thrombin generation in plasma independently of FXII. In purified systems, histones induced platelet aggregation; P-selectin, phosphatidylserine, and FV/Va expression; and prothrombinase activity. Blocking platelet TLR2 and TLR4 with mAbs reduced the percentage of activated platelets and lowered the amount of thrombin generated in PRP. These data show that histone-activated platelets possess a procoagulant phenotype that drives plasma thrombin generation and suggest that TLR2 and TLR4 mediate the activation process.

  4. Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4

    PubMed Central

    Semeraro, Fabrizio; Ammollo, Concetta T.; Morrissey, James H.; Dale, George L.; Friese, Paul; Esmon, Naomi L.

    2011-01-01

    The release of histones from dying cells is associated with microvascular thrombosis and, because histones activate platelets, this could represent a possible pathogenic mechanism. In the present study, we assessed the influence of histones on the procoagulant potential of human platelets in platelet-rich plasma (PRP) and in purified systems. Histones dose-dependently enhanced thrombin generation in PRP in the absence of any trigger, as evaluated by calibrated automated thrombinography regardless of whether the contact phase was inhibited. Activation of coagulation required the presence of fully activatable platelets and was not ascribable to platelet tissue factor, whereas targeting polyphosphate with phosphatase reduced thrombin generation even when factor XII (FXII) was blocked or absent. In the presence of histones, purified polyphosphate was able to induce thrombin generation in plasma independently of FXII. In purified systems, histones induced platelet aggregation; P-selectin, phosphatidylserine, and FV/Va expression; and prothrombinase activity. Blocking platelet TLR2 and TLR4 with mAbs reduced the percentage of activated platelets and lowered the amount of thrombin generated in PRP. These data show that histone-activated platelets possess a procoagulant phenotype that drives plasma thrombin generation and suggest that TLR2 and TLR4 mediate the activation process. PMID:21673343

  5. Magnesium Sulfate as an Alternative In Vitro Anticoagulant for the Measurement of Platelet Parameters?

    PubMed

    Mannuß, Steffen; Schuff-Werner, Peter; Dreißiger, Katrin; Kohlschein, Peter

    2016-06-01

    There are conflicting reports on the reliable measurement of platelet count and mean platelet volume (MPV) using EDTA or citrate. The anticoagulant properties of magnesium sulfate (MgSO4) are known from the literature. The aim of this study was to evaluate MgSO4 as an in vitro anticoagulant for platelet count, MPV, platelet distribution width, and platelet activation. Whole blood from volunteers was anticoagulated by EDTA, citrate, or MgSO4 Platelets were counted by the XE 5000 (Sysmex, Norderstedt, Germany) impedance and fluorescence optical technique. The mean impedance platelet counts were 227.7, 197.0, and 201.1 × 10(9)/L in EDTA-, citrate-, or MgSO4-anticoagulated blood, respectively. The counts were 4.7% higher (EDTA) after 3 hours of storage but 4% lower in citrate-anticoagulated blood. The counts in magnesium samples remained stable. The MPV was 10.4 fL (EDTA), 9.5 fL (citrate), and 9.3 fL (MgSO4). EDTA samples showed cell swelling within the first 3 hours. This was lower in citrate and only marginal in magnesium samples. High activation of platelets was observed only in EDTA samples. Magnesium anticoagulation might be advantageous for more reliable MPV measurements. Although platelet count is underestimated when the impedance method is used, the platelet count reveals similar results when measured by the fluorescent optical method. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Rhesus monkey platelets

    SciTech Connect

    Harbury, C.B.

    1986-03-01

    The purpose of this abstract is to describe the adenine nucleotide metabolism of Rhesus monkey platelets. Nucleotides are labelled with /sup 14/C-adenine and extracted with EDTA-ethanol (EE) and perchlorate (P). Total platelet ATP and ADP (TATP, TADP) is measured in the Holmsen Luciferase assay, and expressed in nanomoles/10/sup 8/ platelets. TR=TATP/TADP. Human platelets release 70% of their TADP, with a ratio of released ATP/ADP of 0.7. Rhesus platelets release 82% of their TADP, with a ratio of released ATP/ADP of 0.33. Thus, monkey platelets contain more ADP than human platelets. Thin layer chromatography of EE gives a metabolic ratio of 11 in human platelets and 10.5 in monkey platelets. Perchlorate extracts metabolic and actin bound ADP. The human and monkey platelets ratios were 5, indicating they contain the same proportion of actin. Thus, the extra ADP contained in monkey platelets is located in the secretory granules.

  7. Platelets in neonates: central mediators in haemostasis, antimicrobial defence and inflammation.

    PubMed

    Andres, Oliver; Schulze, Harald; Speer, Christian P

    2015-01-01

    Platelets are not only centrally involved in haemostasis, but also in antimicrobial defence and inflammation. Since evaluation of platelet physiology in the particular patient group of preterm and term neonatal infants is highly restricted for ethical reasons, there are hardly any data available in healthy and much less in extremely immature or ill neonates. By summarising current knowledge and addressing both platelet researchers and neonatologists, we describe neonatal platelet count and morphology, report on previous analyses of neonatal platelet function in primary haemostasis and provide insights into recent advances in platelet immunology that considerably impacts our clinical view on the critically ill neonatal infant. We conclude that neonatal platelets, originating from liver megakaryocytes, substantially differ from adult platelets and may play a pivotal role in the pathophysiology of neonatal sepsis or intraventricular haemorrhage, both complications which seriously augment perinatal morbidity and mortality.

  8. Altered arachidonic acid metabolism and platelet size in atopic subjects

    SciTech Connect

    Audera, C.; Rocklin, R.; Vaillancourt, R.; Jakubowski, J.A.; Deykin, D.

    1988-03-01

    The release and metabolism of endogenous arachidonic acid (AA) in physiologically activated platelets obtained from 11 atopic patients with allergic rhinitis and/or asthma was compared to that of sex- and age-matched nonatopic controls. Prelabeled (/sup 3/H)AA platelets were stimulated with thrombin or collagen and the amount of free (/sup 3/H)AA and radiolabeled metabolites released were measured by high-performance liquid chromatography. The results obtained indicate that although the incorporation of (/sup 3/H)AA into platelet phospholipids and total release of /sup 3/H-radioactivity upon stimulation were comparable in the two groups, the percentage of /sup 3/H-radioactivity released from platelets as free AA was significantly lower (P less than 0.01) in the atopic group. The reduction in free (/sup 3/H)AA was accompanied by an increase (P less than 0.01) in the percentage of /sup 3/H-radioactivity released as cyclooxygenase products in atopic platelets (compared to nonatopic cells) after stimulation with 10 and 25 micrograms/ml collagen. The amount of platelet lipoxygenase product released was comparable between the two groups. Although the blood platelet counts were similar, the mean platelet volume was statistically higher (P less than 0.01) in the atopic group. These results indicate that arachidonic acid metabolism in atopic platelets is altered, the pathophysiological significance of which remains to be clarified.

  9. Eltrombopag enhances platelet adhesion by upregulating the expression of glycoprotein VI in patients with chronic immune thrombocytopenic purpura.

    PubMed

    Chiou, Tzeon-Jye; Chang, Yi-Fang; Wang, Ming-Chung; Kao, Chen-Wei; Lin, Hsuan-Yu; Chen, Tsai-Yun; Hsueh, Erh-Jung; Lan, Yii-Jenq; Sung, Yung-Chuan; Lin, Sheng-Feng; Bai, Li-Yuan; Chen, Caleb G

    2015-12-01

    Eltrombopag, a thrombopoietin receptor agonist, has been approved for the treatment of patients with immune thrombocytopenia because of its abilities to enhance platelet production and reduce hemorrhage. Both platelet count and platelet adhesion are crucial to stop bleeding. Although eltrombopag is known to improve platelet counts, its effects on platelet adhesion are not yet known. This study aimed to assess the efficacy of eltrombopag on platelet production and platelet adhesive affinity. To evaluate the efficacy of low-dose eltrombopag (25 mg) for patients with chronic refractory immune thrombocytopenic purpura (ITP) and to determine the ex vivo platelet adhesion ability before and after treatment with eltrombopag, we conducted an open-label, multicenter study in which 25 Taiwanese patients with chronic ITP were enrolled. During the 6-month evaluation, the starting and maximum doses of eltrombopag were 25 and 50 mg, respectively, to maintain the platelet count of ≥50,000 per μL. Flow-based adhesion assay was used to detect the percentage of platelets adhering to immobilized von Willebrand factor-collagen on microslides. Of the enrolled patients, 48% achieved a platelet count of ≥50,000 per μL. Interestingly, 83% of all responders required 25 mg of eltrombopag daily to achieve the target platelet count. In addition, the percentage of bleeding patients was significantly reduced in both responders and nonresponders by 50% from the baseline level throughout the treatment period. The ex vivo platelet adhesion capacity was elevated after the 6-month eltrombopag treatment in both responders and nonresponders. Furthermore, glycoprotein VI (GPVI) expression was significantly upregulated after treatment with eltrombopag. Low-to-intermediate dose of eltrombopag showed good efficacy to expedite platelet production and augment platelet adhesion. These 2 factors might explain the efficacy of eltrombopag in ameliorating hemorrhage in patients with ITP. Copyright © 2015

  10. Increasing platelet concentrations in leukocyte-reduced platelet-rich plasma decrease collagen gene synthesis in tendons.

    PubMed

    Boswell, Stacie G; Schnabel, Lauren V; Mohammed, Hussni O; Sundman, Emily A; Minas, Tom; Fortier, Lisa A

    2014-01-01

    Platelet-rich plasma (PRP) is used for the treatment of tendinopathy. There are numerous PRP preparations, and the optimal combination of platelets and leukocytes is not known. Within leukocyte-reduced PRP (lrPRP), there is a plateau effect of platelet concentration, with increasing platelet concentrations being detrimental to extracellular matrix synthesis. Controlled laboratory study. Different formulations of lrPRP with respect to the platelet:leukocyte ratio were generated from venous blood of 8 horses. Explants of the superficial digital flexor tendon were cultured in lrPRP products for 96 hours. Platelet-derived growth factor-BB (PDGF-BB), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and interleukin-1β (IL-1β) concentrations were determined in the media by enzyme-linked immu